Title: Targeted Metabolomics Study of Human Plasma Revealed Activation of the Cytochrome P450 Epoxygenase/Epoxide Hydrolase Axis in Patients with IgA Nephropathy Deng BQ, Li MY, Fu X, Luo Y, Qiao Q, Liu JY Ref: J Proteome Res, :, 2022 : PubMed
IgA nephropathy (IgAN) is the most common primary glomerulonephritis and a leading cause of chronic kidney disease. The pathogenic mechanism of IgAN remains largely unknown and thus a specific therapeutic target is lacking. Here, we reported that the cytochrome P450 (CYP) epoxygenase/epoxide hydrolase (EH) axis was activated in the patients and is likely a therapeutic target for IgAN. Specifically, quantitative profiling of the plasma from IgAN patients and healthy controls revealed significant changes in plasma levels of CYP/EH-mediated lipid epoxides and diols. Subsequently, CYP2C8, CYP2C18, CYP2J2, EPHX1, and EPHX2 were found to be significantly increased in whole blood cells at mRNA levels from the IgAN patients when compared with those of healthy controls. Immunohistochemical analysis showed that all five CYPs and two EHs were upregulated in the kidney tissue from IgAN patients when compared with normative renal tissue, but the expression locations of the proteins were different with most of them. Treatment of HK-2 cells with IgA1 increased cell viability, compressed cell apoptosis, and increased the protein levels of CYP2C9, EPHX1, and EPHX2. All the results agreed that CYPs/EHs axis is likely the prophylactic and therapeutic target for IgAN, providing IgAN patients with a new intervention strategy.
Nerve agent (NA) can inhibit acetylcholinesterase (AChE) causing seriously injury at extremely low doses. However, the cruel reality is that the lack of effective cerebral antidotes for treatment of NA poisoning. There is an urgent requirement for the large-scale evaluation and screening of antidotes. An effective NA antidote should include two characteristics: a) to permeate the blood-brain barrier (BBB); 2) to reactivate the inhibited AChE in brain. Existing methods for evaluating reactivators in vitro can only examine the reactivation effect, while the current Transwell model can only evaluate the drug penetration performance for crossing the barrier. In this work, brain microvascular endothelial cells (RBMECs) were inoculated to establish a Transwell model. AChE, NAs and antidotes of reactivators were added into the different chambers to simulate central poisoning and peripheral drug administration. This method can evaluate the reactivation ability and brain penetration ability of compounds at same time, which is a rapidly and accurately way for drug preliminary screening. In addition to small-molecule drugs, a liposomal nanoantidote loaded with the reactivator Asoxime chloride (HI-6)was prepared. This nanoantidote show high reactivation rate against the NA (sarin), evaluated by both this modified model in vitro and animal test, gaining the consistence results.
In flowering plants, strigolactones (SLs) have dual functions as hormones that regulate growth and development, and as rhizosphere signaling molecules that induce symbiosis with arbuscular mycorrhizal (AM) fungi. Here, we report the identification of bryosymbiol (BSB), an SL from the bryophyte Marchantia paleacea. BSB is also found in vascular plants, indicating its origin in the common ancestor of land plants. BSB synthesis is enhanced at AM symbiosis permissive conditions and BSB deficient mutants are impaired in AM symbiosis. In contrast, the absence of BSB synthesis has little effect on the growth and gene expression. We show that the introduction of the SL receptor of Arabidopsis renders M. paleacea cells BSB-responsive. These results suggest that BSB is not perceived by M. paleacea cells due to the lack of cognate SL receptors. We propose that SLs originated as AM symbiosis-inducing rhizosphere signaling molecules and were later recruited as plant hormone.
Title: Independent association of Lp(a) with platelet reactivity in subjects without statins or antiplatelet agents Liu H, Fu D, Luo Y, Peng D Ref: Sci Rep, 12:16609, 2022 : PubMed
The physiological effect of Lp(a) on platelet activity is unclear. Previous studies explored the relationship between Lp(a) and platelet aggregation in patients taking statins and antiplatelet agents, but few was conducted in individuals without the bias of those drugs that either influence Lp(a) or platelet activity. The aim of this study was to assess the relationship between Lp(a) levels and platelet aggregation in subjects not taking statins or antiplatelet drugs. A hospital-based cross-sectional study was conducted to investigate the independent contribution of Lp(a) to platelet activity by controlling the effects of potential confounding factors including lipoprotein-associated phospholipase A2 [Lp-PLA2]. Blood samples were collected from 92 subjects without statins or antiplatelet agents from the Second Xiangya Hospital. The univariate correlation analysis showed a significant correlation between AA-induced average aggregation rate [AAR] and ApoB (r = 0.324, P = 0.002), ApoA1 (r = 0.252, P = 0.015), Lp(a) (r = 0.370, P < 0.001), Lp-PLA2 (r = 0.233, P = 0.025) and platelet counts [PLT] (r = 0.389, P < 0.001). Multivariate regression analysis suggested that Lp(a) contributed independently to AA-induced average aggregation rate (beta = 0.023, P = 0.027) after controlling for the effects of ApoB, Lp-PLA2 and platelet counts. Lp(a) is positively associated with platelet aggregation independent of Lp-PLA2, which may partly account for the atherothrombotic effect of Lp(a).
Title: A network pharmacology-based approach to explore the therapeutic potential of Sceletium tortuosum in the treatment of neurodegenerative disorders Luo Y, Shan L, Xu L, Patnala S, Kanfer I, Li J, Yu P, Jun X Ref: PLoS ONE, 17:e0273583, 2022 : PubMed
Sceletium tortuosum (SCT) has been utilized medicinally by indigenous Koi-San people purportedly for mood elevation. SCT extracts are reported to be neuroprotective and have efficacy in improving cognition. However, it is still unclear which of the pharmacological mechanisms of SCT contribute to the therapeutic potential for neurodegenerative disorders. Hence, this study investigated two aspects-firstly, the abilities of neuroprotective sub-fractions from SCT on scavenging radicals, inhibiting some usual targets relevant to Alzheimer's disease (AD) or Parkinson's disease (PD), and secondly utilizing the network pharmacology related methods to search probable mechanisms using Surflex-Dock program to show the key targets and corresponding SCT constituents. The results indicated sub-fractions from SCT could scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, inhibit acetylcholinesterase (AChE), monoamine oxidase type B (MAO-B) and N-methyl-D-aspartic acid receptor (NMDAR). Furthermore, the results of gene ontology and docking analyses indicated the key targets involved in the probable treatment of AD or PD might be AChE, MAO-B, NMDAR subunit2B (GluN2B-NMDAR), adenosine A2A receptor and cannabinoid receptor 2, and the corresponding constituents in Sceletium tortuosum might be N-trans-feruloyl-3-methyldopamine, dihydrojoubertiamine and other mesembrine type alkaloids. In summary, this study has provided new evidence for the therapeutic potential of SCT in the treatment of AD or PD, as well as the key targets and notable constituents in SCT. Therefore, we propose SCT could be a natural chemical resource for lead compounds in the treatment of neurodegenerative disorders.
Title: Biosensor Based on Covalent Organic Framework Immobilized Acetylcholinesterase for Ratiometric Detection of Carbaryl Luo Y, Wu N, Wang L, Song Y, Du Y, Ma G Ref: Biosensors (Basel), 12:, 2022 : PubMed
A ratiometric electrochemical biosensor based on a covalent organic framework (COF(Thi-TFPB)) loaded with acetylcholinesterase (AChE) was developed. First, an electroactive COF(Thi-TFPB) with a two-dimensional sheet structure, positive charge and a pair of inert redox peaks was synthesized via a dehydration condensation reaction between positively charged thionine (Thi) and 1,3,5-triformylphenylbenzene (TFPB). The immobilization of AChE on the positively charged electrode surface was beneficial for maintaining its bioactivity and achieving the best catalytic effect; therefore, the positively charged COF(Thi-TFPB) was an appropriate support material for AChE. Furthermore, the COF(Thi-TFPB) provided a stable internal reference signal for the constructed AChE inhibition-based electrochemical biosensor to eliminate various effects which were unrelated to the detection of carbaryl. The sensor had a linear range of 2.2-60 microM with a detection limit of 0.22 microM, and exhibited satisfactory reproducibility, stability and anti-interference ability for the detection of carbaryl. This work offers a possibility for the application of COF-based materials in the detection of low-level pesticide residues.
The red imported fire ant (Solenopsis invicta) is one of the deadliest invasive ant species that threatens the world by disrupting biodiversity, important functions within a natural ecosystem, and community structure. They are responsible for huge economic losses in the infested countries every year. Synthetic insecticides, especially indoxacarb, have been broadly used to control S. invicta for many years. However, the biochemical response of S. invicta to indoxacarb remains largely undiscovered. Here, we used the sublethal doses of indoxacarb on the S. invicta collected from the eight different cities of Southern China. The alteration in the transcriptome profile of S. invicta following sublethal dosages of indoxacarb was characterized using high-throughput RNA-seq technology. We created 2 libraries, with 50.93 million and 47.44 million clean reads for indoxacarb treatment and control, respectively. A total of 2018 unigenes were regulated after insecticide treatment. Results indicated that a total of 158 differentially expressed genes (DEGs) were identified in the indoxacarb-treated group, of which 100 were significantly upregulated and 58 were downregulated, mostly belonging to the detoxification enzymes, such as AChE, CarE, and GSTs. Furthermore, results showed that most of these DEGs were found in several KEGG pathways, including steroid biosynthesis, other drug metabolizing enzymes, glycerolipid metabolism, chemical carcinogenesis, drug-metabolizing cytochrome P450, glutathione metabolism, glycerophospholipid metabolism, glycolysis/gluconeogenesis, and metabolism of xenobiotics. Together, these findings indicated that indoxacarb causes significant alteration in the transcriptome profile and signaling pathways of S. invicta, providing a foundation for further molecular inquiry.
Insecticide resistance poses many challenges in insect pest control, particularly in the control of destructive pests such as red imported fire ants (Solenopsis invicta). In recent years, beta-cypermethrin and fipronil have been extensively used to manage invasive ants, but their effects on resistance development in S. invicta are still unknown. To investigate resistance development, S. invicta was collected from populations in five different cities in Guangdong, China. The results showed 105.71- and 2.98-fold higher resistance against fipronil and beta-cypermethrin, respectively, in the Guangzhou population. The enzymatic activities of acetylcholinesterase, carboxylases, and glutathione S-transferases significantly increased with increasing beta-cypermethrin and fipronil concentrations. Transcriptomic analysis revealed 117 differentially expressed genes (DEGs) in the BC-ck vs. BC-30 treatments (39 upregulated and 78 downregulated), 109 DEGs in F-ck vs. F-30 (33 upregulated and 76 downregulated), and 499 DEGs in BC-30 vs. F-30 (312 upregulated and 187 downregulated). Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that DEGs associated with insecticide resistance were significantly enriched in metabolic pathways, the AMPK signaling pathway, the insulin signaling pathway, carbon metabolism, peroxisomes, fatty acid metabolism, drug metabolism enzymes and the metabolism of xenobiotics by cytochrome P450. Furthermore, we found that DEGs important for insecticide detoxification pathways were differentially regulated under both insecticide treatments in S. invicta. Comprehensive transcriptomic data confirmed that detoxification enzymes play a significant role in insecticide detoxification and resistance development in S. invicta in Guangdong Province. Numerous identified insecticide-related genes, GO terms, and KEGG pathways indicated the resistance of S. invicta workers to both insecticides. Importantly, this transcriptome profile variability serves as a starting point for future research on insecticide risk evaluation and the molecular mechanism of insecticide detoxification in invasive red imported fire ants.
Title: Single-atom Ce-N-C nanozyme bioactive paper with a 3D-printed platform for rapid detection of organophosphorus and carbamate pesticide residues Song G, Zhang J, Huang H, Wang X, He X, Luo Y, Li JC, Huang K, Cheng N Ref: Food Chem, 387:132896, 2022 : PubMed
Rapid detection of pesticide residues based on enzyme mimics has recently attracted much interest. However, most nanozymes have low activity. Herein, a "single-atom Ce-N-C nanozyme" (SACe-N-C nanozyme) was rationally devised and verified to mimic peroxidase (POD-like) with superior activity. Based on its high POD-like activities and cascaded catalytic reactions with acetylcholinesterase (AChE), we constructed a bioactive paper for the detection of pesticide residues, which offered a portable approach to monitor fruits and vegetables within 30 min. More importantly, a 3D printed platform was integrated on the basis of SACe-N-C bioactive paper to achieve on-site portable testing of omethoate, methamidophos, carbofuran, and carbosulfan, showing limits of detection (LODs) of 55.83, 71.51, 81.81, and 74.98 ng/mL, respectively. The recovery rates were 84.09-104.68%. This study provided new insight into the design of novel single-atom nanozymes for cascaded catalytic detection and other rapid detection applications with high efficiency and low cost.
Title: Inhibitors of soluble epoxide hydrolase on acute lung injury: a meta-analysis of preclinical studies Tao W, Xu G, Luo Y, Li PS Ref: Inflammopharmacology, :, 2022 : PubMed
INTRODUCTION: This study investigated the effects of soluble epoxide hydrolase (sEH) inhibitors on acute lung injury (ALI) using the measure of meta-analysis. METHODS: Relative publications were systematic reviewed and retrieved by searching electronic databases including the Cochrane Library, PubMed, China National Knowledge Infrastructure, Wanfang Data, and Google Scholar. RESULTS: Seven animal studies were included in this meta-analysis. Our result showed that the lung injury scores (SMD = - 2.31, 95% CI - 3.50 to - 1.12) and lung wet to dry weight ratios (WMD-1.44, 95% CI - 1.69 to - 1.18) were reduced in sEH inhibitors-treated animals compared with control. The mortality was improved by sEH inhibitors at 48 h (RR = 0.62, 95% CI 0.42 to 0.92), 72 h, and 120 h, but not at 24 h (RR = 0.59, 95% CI 0.35 to 1.01) and 96 h, after induction of ALI model. CONCLUSIONS: The sEH inhibitor is a potent candidate of pharmacological agents for ALI/acute respiratory distress syndrome, as its effects on improvement of lung injury and mortality in preclinical researches.
In our previous study, microRNA (miR)-199a-3p was found to be the most upregulated miRNA in mammary gland tissue during the non-lactation period compared with the peak-lactation period. However, there have been no reports describing the function of miR-199a-3p in ovine mammary epithelial cells (OMECs) and the biological mechanisms by which the miRNA affects cell proliferation and milk fat synthesis in sheep. In this study, the effect of miR-199a-3p on viability, proliferation, and milk fat synthesis of OMECs was investigated, and the target relationship of the miRNA with very low-density lipoprotein receptor (VLDLR) was also verified. Transfection with a miR-199a-3p mimic increased the viability of OMECs and the number of Edu-labeled positive OMECs. In contrast, a miR-199-3p inhibitor had the opposite effect with the miR-199a-3p mimic. The expression levels of three marker genes were also regulated by both the miR-199a-3p mimic and miR-199-3p inhibitor in OMECs. Together, these results suggest that miR-199a-3p promotes the viability and proliferation of OMECs. A dual luciferase assay confirmed that miR-199a-3p can target VLDLR by binding to the 3'-untranslated regions (3'UTR) of the gene. Further studies found a negative correlation in the expression of miR-199a-3p with VLDLR. The miR-199a-3p mimic decreased the content of triglycerides, as well as the expression levels of six milk fat synthesis marker genes in OMECs, namely, lipoprotein lipase gene (LPL), acetyl-CoA carboxylase alpha gene (ACACA), fatty acid binding protein 3 gene (FABP3), CD36, stearoyl-CoA desaturase gene (SCD), and fatty acid synthase gene (FASN). The inhibition of miR-199a-3p increased the level of triglycerides and the expression of LPL, ACACA, FABP3, SCD, and FASN in OMECs. These findings suggest that miR-199a-3p inhibited milk fat synthesis of OMECs. This is the first study to reveal the molecular mechanisms by which miR-199a-3p regulates the proliferation and milk fat synthesis of OMECs in sheep.
Hormone-sensitive lipase is one of the rate-determining enzymes in the hydrolysis of triglyceride, playing a crucial role in lipid metabolism. However, the role of HSL-mediated lipolysis in systemic nutrient homeostasis has not been intensively understood. Therefore, we used CRISPR/Cas9 technique and Hsl inhibitor (HSL-IN-1) to establish hsla-deficient (hsla(-/)-) and Hsl-inhibited zebrafish models, respectively. As a result, the hsla(-/)- zebrafish showed retarded growth and reduced oxygen consumption rate, accompanied with higher mRNA expression of the genes related to inflammation and apoptosis in liver and muscle. Furthermore, hsla(-/)- and HSL-IN-1 treated zebrafish both exhibited severe fat deposition, whereas their expressions of the genes related to lipolysis and fatty acid oxidation were markedly reduced. The thin layer chromatography results also showed that the dysfunction of Hsl changed the whole body lipid profile, including increasing the content of TG and decreasing the proportion of PL. In addition, the systemic metabolic pattern was remodeled in hsla(-/)- and HSL-IN-1 treated zebrafish. The dysfunction of Hsl lowered the glycogen content in liver and muscle, enhanced the utilization of glucose plus the expressions of glucose transporter and glycolysis genes. Besides, the whole-body protein content had significantly decreased in the hsla(-/)- and HSL-IN-1 treated zebrafish, accompanied with the lower activation of the mTOR pathway and enhanced protein and amino acid catabolism. Taken together, Hsl plays an essential role in energy homeostasis, and its dysfunction would cause the disturbance of lipid catabolism but enhanced breakdown of glycogen and protein for energy compensation.
Title: Effect of thiamethoxam on the behavioral profile alteration and toxicity of adult zebrafish at environmentally relevant concentrations Yang J, Guo C, Luo Y, Fan J, Wang W, Yin X, Xu J Ref: Sci Total Environ, 858:159883, 2022 : PubMed
Thiamethoxam (THM) is a commercial neonicotinoid insecticide with broad-spectrum insecticidal activity. It has been widely detected in the aquatic environment, but its behavioral toxicity on aquatic organisms received limited attention. In this study, adult zebrafish were exposed to THM at three levels (0.1, 10, and 1000 g/L) for 45 days to investigate its effect on their ecological behavior, histopathology, bioaccumulation, and stress response. The bioconcentration factor in zebrafish brain was significantly higher (p < 0.05) at low concentration of THM (0.1 g/L) than in other treatment groups. In terms of individual behavior, the locomotor activity, aggregation, and social activity of fish were enhanced after THM exposure, but the memory of the food zone was disturbed and abnormal swimming behavior was observed. THM exposure caused brain tissue necrosis, erythrocyte infiltration, cloudy swelling, and other pathological changes in brain tissue and affected the concentrations of acetylcholinesterase and cortisol related to neurotoxicity. The condition factor and organ coefficients (brain, heart, and intestine) of zebrafish were markedly impacted by THM treatment at 0.1 and 1000 g/L, respectively. This finding showed that THM was more harmful to fish behavior than lethality, reproduction, and growth, and a behavioral study can be a useful tool for ecological risk assessment.
Title: Serum levels of IL-12, IL-18, and IL-21 are indicators of viral load in patients chronically infected with HBV Zhou F, Xiong H, Zhen S, Chen A, Huang M, Luo Y Ref: Brazilian Journal of Medical & Biological Research, 55:e12320, 2022 : PubMed
This study explored the correlation between interleukins (IL)-12, IL-18, and IL-21 and the viral load in patients with chronic hepatitis B virus (HBV). A total of 142 patients were consecutively enrolled. All were hepatitis B surface antigen (HBsAg)-positive for >6 months and did not receive drug therapy. An ELISA kit was used to test the IL-12, IL-18, IL-21, and acetylcholinesterase (AchE) levels in serum samples from chronic HBV patients and healthy control groups. The amounts of IL-12 and IL-18 were highest in the 5-6log10 (high viral load) group, while IL-21 was highest in the 3-4log10 (low viral load) group. Also, the IL-21 amount was decreased in the HBsAg+/HBeAg/HBcAb+ group, and IL-12, IL-18, and IL-21 were decreased in the normal alanine aminotransferase (ALT) group compared to the abnormal ALT group. These data suggested that IL-12, IL-18, and IL-21 serum levels were positively correlated with disease progression and could reflect disease severity for different HBV-DNA loads. Detection of IL-12, IL-18, and IL-21 levels was found to be helpful for evaluating the degree of liver cell damage and predicting the progression of hepatitis.
Title: IsPETase represents a novel biocatalyst for poly (ethylene terephthalate) (PET) hydrolysis Kan Y, He L, Luo Y, Bao R Ref: Chembiochem, :, 2021 : PubMed
Poly (ethylene terephthalate) (PET) is one of the most widely used synthetic polyesters but also a main cause of plastic pollution. Since the chemical degradation of PET would be uneconomical and rather burdensome, considerable efforts have been devoted to exploring enzymatic processes for the disposal of PET waste. Many PET hydrolyzing enzymes have been consecutively reported in recent decades, some of which demonstrate excellent potential for industrial applications. This review sets out to summarize the investigation status of Is PETase, a cutinase-like enzyme from I. sakaiensis possessing ability to degrade the crystalline PET, and to gain further insight into the structure-function relationship of Is PETase. Benefiting from the continuing identification of novel cutinase-like proteins and growing availability of the engineered Is PETase, we may anticipate future developments in this type of enzyme would generate suitable biocatalyst for industrial use.
Title: Red-to-blue paper-based colorimetric sensor integrated with smartphone for point-of-use analysis of cerebral AChE upon Cd(2+) exposure Liu C, Luo Y, Wen H, Qi Y, Shi G, Deng J, Zhou T Ref: Nanoscale, :, 2021 : PubMed
Herein, combined with a pervasive smartphone installed with a color recognition app, dual-responsive CDs@Eu/GMP ICPs were designed as a red-to-blue paper-based colorimetric sensor for the point-of-use analysis of cerebral acetylcholinesterase (AChE) upon Cd2+ exposure. Blue-emitting CDs with multi-functional groups as guests were encapsulated into the network of Eu/GMP ICPs to obtain CDs@Eu/GMP ICPs with the sensitized red fluorescence of Eu3+. With the presence of thiocholine (TCh), derived from acetylthiocholine (ATCh) hydrolyzed by AChE, the coordination environment of the CDs@Eu/GMP ICPs was interrupted, leading to the collapse of the CDs@Eu/GMP ICP network and the corresponding release of guest CDs into the surrounding environment. Consequently, the sensitized red fluorescence of Eu3+ decreased and the blue fluorescence of the CDs increased. This obvious red-to-blue fluorescent color changes of CDs@Eu/GMP ICPs on test paper could then be integrated with the smartphone for point-of-use analysis of cerebral AChE upon Cd2+ exposure, which not only offers a new analytical platform for a better understanding of the environmental risk of Alzheimer's Dementia (AD), but also holds great potential in the early diagnosis of AD even at the asymptomatic stage with the decrease in CSF AChE as an early biomarker.
Title: Delta-containing GABA(A) receptors in pain management: Promising targets for novel analgesics Luo Y, Kusay AS, Jiang T, Chebib M, Balle T Ref: Neuropharmacology, 195:108675, 2021 : PubMed
Communication between nerve cells depends on the balance between excitatory and inhibitory circuits. GABA, the major inhibitory neurotransmitter, regulates this balance and insufficient GABAergic activity is associated with numerous neuropathological disorders including pain. Of the various GABA(A) receptor subtypes, the delta-containing receptors are particularly interesting drug targets in management of chronic pain. These receptors are pentameric ligand-gated ion channels composed of alpha, beta and delta subunits and can be activated by ambient levels of GABA to generate tonic conductance. However, only a few ligands preferentially targeting delta-containing GABA(A) receptors have so far been identified, limiting both pharmacological understanding and drug-discovery efforts, and more importantly, understanding of how they affect pain pathways. Here, we systemically review and discuss the known drugs and ligands with analgesic potential targeting delta-containing GABA(A) receptors and further integrate the biochemical nature of the receptors with clinical perspectives in pain that might generate interest among researchers and clinical physicians to encourage analgesic discovery efforts leading to more efficient therapies.
BACKGROUND: Panax ginseng (PG) and red ginseng (RG) are considered to be effective anti-aging treatments. However, evidence of their therapeutic mechanisms and difference in anti-aging effects is lacking. PURPOSE: To explore the potential therapeutic mechanisms of RG and PG in brain damage in D-Gal-induced aging mice, and evaluate the difference in anti-aging effects caused by their compositional differences. METHODS: We first tested the chemical components in PG and RG. In D-Gal aging mouse model, RG and PG (800 mg/kg) were orally administered for 9 weeks. The mice performed the Radial Arm Maze (RAM) behavior test. We collected blood, brain tissue, and fecal samples and performed biochemical analysis, histological examination, western blot, and Illumina MiSeq sequencing analysis. RESULTS: The results of component analysis showed that the total polyphenols and rare ginsenosides were present in RG in 3.2, and 2.2 fold greater concentrations, respectively, compared to PG, while the proportion of non-starch polysaccharides in the crude polysaccharides of RG was 1.94 fold greater than that of PG. In D-Gal-induced aging mice, both PG and RG could prevent the increase in acetylcholinesterase (AChE), and malondialdehyde (MDA) levels, and improved the expression of superoxide dismutase (SOD), and catalase (CAT) in the serum. Meanwhile, both PG and RG could ameliorate brain tissue architecture and behavioral trial. In addition, the D-Gal-induced translocation of nuclear factor-kappaB (NF-kappaB), as well as activation of the pro-apoptotic factors Caspase-3 and the PI3K/Akt pathways were inhibited by PG and RG. Overall, both PG and RG exerted anti-aging effects, with RG stronger than PG. Finally, although both PG and RG regulated the diversity of gut microbes, RG appeared to aggravate the increase in probiotics, such as Bifidobacterium and Akkermania, and the decrease in inflammatory bacteria to a greater extent compared to PG. CONCLUSION: Our results suggest that RG is more conducive to delay the D-Gal-induced aging process than PG, with possible mechanisms including beneficial changes in brain structure, cognitive functions, oxidative stress inhibition, and gut microbiome structure and diversity than PG, These mechanisms may rely on the presence of more total polyphenols, rare ginsenosides and non-starch polysaccharides in RG.
Title: TRPV4 Regulates Soman-Induced Status Epilepticus and Secondary Brain Injury via NMDA Receptor and NLRP3 Inflammasome Wang S, He H, Long J, Sui X, Yang J, Lin G, Wang Q, Wang Y, Luo Y Ref: Neurosci Bull, :, 2021 : PubMed
Nerve agents are used in civil wars and terrorist attacks, posing a threat to public safety. Acute exposure to nerve agents such as soman (GD) causes serious brain damage, leading to death due to intense seizures induced by acetylcholinesterase inhibition and neuronal injury resulting from increased excitatory amino-acid levels and neuroinflammation. However, data on the anticonvulsant and neuroprotective efficacies of currently-used countermeasures are limited. Here, we evaluated the potential effects of transient receptor vanilloid 4 (TRPV4) in the treatment of soman-induced status epilepticus (SE) and secondary brain injury. We demonstrated that TRPV4 expression was markedly up-regulated in rat hippocampus after soman-induced seizures. Administration of the TRPV4 antagonist GSK2193874 prior to soman exposure significantly decreased the mortality rate in rats and reduced SE intensity. TRPV4-knockout mice also showed lower incidence of seizures and higher survival rates than wild-type mice following soman exposure. Further in vivo and in vitro experiments demonstrated that blocking TRPV4 prevented NMDA receptor-mediated glutamate excitotoxicity. The protein levels of the NLRP3 inflammasome complex and its downstream cytokines IL-1beta and IL-18 increased in soman-exposed rat hippocampus. However, TRPV4 inhibition or deletion markedly reversed the activation of the NLRP3 inflammasome pathway. In conclusion, our study suggests that the blockade of TRPV4 protects against soman exposure and reduces brain injury following SE by decreasing NMDA receptor-mediated excitotoxicity and NLRP3-mediated neuroinflammation. To our knowledge, this is the first study regarding the "dual-switch" function of TRPV4 in the treatment of soman intoxication.
Title: Novel amide derivatives containing an imidazo[1,2-a]pyridine moiety: Design, synthesis as potential nematicidal and antibacterial agents Wei C, Huang J, Luo Y, Wang S, Wu S, Xing Z, Chen J Ref: Pestic Biochem Physiol, 175:104857, 2021 : PubMed
To discover new nematicides, a series of novel amide derivatives containing an imidazo[1,2-a]pyridine moeity were designed and synthesized. Among the title compounds, compounds 3 and 27 exhibited good nematicidal activities against Aphelenchoides besseyi (rice white-tip nematode), with LC(50) values against of 27.3 and 35.9 mg/L, respectively, which were superior to that of fosthiazate (45.4 mg/L). Meanwhile, the LC(50) value of compound 27 against Caenorhabditis elegans was 5.7 mg/L, which was superior to that of fosthiazate (77.2 mg/L). Compound 27 not only binds well to acetylcholinesterase (AChE) of nematodes, but also has a good inhibitory activity against AChE. Thus, AChE may be a potential target of compound 27 against nematodes. Unexpectedly, compound 28 exhibited excellent antibacterial activities with EC(50) values of 1.2 and 3.1 mg/L against Xanthomonas oryzae pv. oryzae (Xoo) and Xanthomonas oryzae pv. oryzicola (Xoc), respectively, which were superior to those of bismerthiazol (68.6 and 77.1 mg/L) and thiodiazole copper (80.8 and 96.6 mg/L). The curative and protective activities of compound 28 against bacterial leaf blight were 37.0% and 36.8% at 50 mg/L, respectively, which were higher than those of thiodiazole copper (16.1% and 15.5%). In addition, compound 28 may inhibit the growth of Xoo by affecting the production of cell membranes and extracellular polysaccharides. Amide derivatives containing an imidazo[1,2-a]pyridine moeity can be used as good lead-structures to discover new nematicidal and antibacterial agents in the future.
Title: New perspective on the regulation of acetylcholinesterase via the aryl hydrocarbon receptor Xie HQ, Ma Y, Fu H, Xu T, Luo Y, Liu Y, Chen Y, Xu L, Xia Y, Zhao B Ref: Journal of Neurochemistry, 158:1254, 2021 : PubMed
Acetylcholinesterase (AChE, EC 3.1.1.7) plays important roles in cholinergic neurotransmission and has been widely recognized as a biomarker for monitoring pollution by organophosphate (OP) and carbamate pesticides. Dioxin is an emerging environmental AChE disruptor and is a typical persistent organic pollutant with multiple toxic effects on the nervous system. Growing evidence has shown that there is a significant link between dioxin exposure and neurodegenerative diseases and neurodevelopmental disorders, most of which involve AChE and cholinergic dysfunctions. Therefore, an in-depth understanding of the effects of dioxin on AChE and the related mechanisms of action might help to shed light on the molecular bases of dioxin impacts on the nervous system. In the past decade, the effects of dioxins on AChE have been revealed in cultured cells of different origins and in rodent animal models. Unlike OP and carbamate pesticides, dioxin-induced AChE disturbance is not due to direct inhibition of enzymatic activity; instead, dioxin causes alterations of AChE expression in certain models. As a widely accepted mechanism for most dioxin effects, the aryl hydrocarbon receptor (AhR)-dependent pathway has become a research focus in studies on the mechanism of action of dioxin-induced AChE dysregulation. In this mini-review, the effects of dioxin on AChE and the diverse roles of the AhR pathway in AChE regulation are summarized. Additionally, the involvement of AhR in AChE regulation during different neurodevelopmental processes is discussed. These AhR-related findings might also provide new insight into AChE regulation triggered by diverse xenobiotics capable of interacting with AhR.
Acrylamide (ACR) is a recognized toxin that is known to induce neurotoxicity in humans and experimental animals. This study aimed to investigate the toxic effects of subacute exposure of the motor endplate (MEP) of the gastrocnemius in rats to ACR. All rats were randomly divided into control, 9, 18, and 36 mg/kg ACR groups, and ACR was administered by gastric gavage for 21 days. The behavioral tests were performed weekly. On the 22(nd) day, the wet weight of the gastrocnemius was measured. The changes in muscle fiber structure, nerve endings, and MEP in the gastrocnemius were examined by hematoxylin-eosin (HE) and gold chloride staining. Acetylcholinesterase (AChE) content in the gastrocnemius was detected by AChE staining. The expression of AChE and calcitonin gene-related peptide was detected by immunohistochemistry and western blot. Rats exposed to ACR showed a significant increase in gait scores and hind limb splay distance compared with the control group, and the wet weight of the gastrocnemius was reduced, HE staining showed that the muscle fiber structure of the gastrocnemius became thin and the arrangement was dense with nuclear aggregation, gold chloride staining showed that nerve branches decreased and became thin, nerve fibers became short and light, the number of MEPs was decreased, the staining became light, and the structure was not clear. AChE staining showed that the number of MEPs was significantly reduced after exposure to ACR, the shape became small, and the AChE content decreased in a dose-dependent manner. Immunohistochemistry and western blot analysis results of the expression levels of AchE and CGRP showed a decreasing trend as compared to the control group with increasing ACR exposure dose. The reduction in protein levels may be the mechanism by which ACR has a toxic effect on the MEP in the gastrocnemius of rats.
Title: Gestational and lactational exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin in mice: Neurobehavioral effects on female offspring Sha R, Chen Y, Wang Y, Luo Y, Liu Y, Ma Y, Li Y, Xu L, Xie HQ, Zhao B Ref: Sci Total Environ, 752:141784, 2020 : PubMed
Emerging evidence suggests that perinatal dioxin exposure affects neurodevelopment and impairs multiple brain functions, including cognitive, language, learning and emotion, in the offspring. However, the impacts of gestational and lactational exposure to dioxin on behavior and related molecular events are still not fully understood. In this study, female C57BL/6J mice were orally administered three doses of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) (0.1 or 10 mug/kg body weight (bw)) during the pregnancy and lactation periods. The locomotion, exploration and anxiety-related behaviors were examined by an open field test of the young adult female offspring at postnatal day 68. We found that the maternal TCDD exposure, particularly at a low dose, increased movement ability, novelty-exploration and certain anxiety-related behaviors in the offspring. Such hyperactivity-like behaviors were accompanied by the upregulation of certain genes associated with cholinergic neurotransmission or synaptogenesis in the offspring brain. In accordance with the potential enhancement of cholinergic neurotransmission due to the gene upregulations, the enzymatic activity of acetylcholinesterase was decreased, which might lead to excess acetylcholine and consequent hyper-excitation at the synapses. Thus, we found that gestational and lactational TCDD exposure at low dose caused hyperactivity-like behaviors in young adult female offspring and speculated the enhancement of cholinergic neurotransmission and synaptogenesis as potential molecular events underlying the neurobehavioral effects.
Selenium is an essential element but toxic at high levels in animals. The effects of Se on growth performance and the immune system in Nile tilapia remain inconclusive. In this study, Nile tilapia Oreochromis niloticus was fed on selenium yeast (Se(Y))- and selenite (Se(IV))-enriched feed at 0, 3, 6, and 12 mug/g (dry wt) for 45 and 90 d. The growth, bioaccumulation, biochemical markers related to antioxidant, immunological, nervous and digestive systems were evaluated in various fish tissues (liver, intestine, kidney, muscle, brain, spleen, gills). The results showed that the accumulation of Se(Y) was 1.3-2 folds of Se(IV) in most tissues. The growth of tilapia was enhanced by both Se(Y) and Se(IV) at 3 mug/g after 90 d, with Se(Y) better than Se(IV) in tilapia feed. After 45 d, the levels of lipid peroxidation, the activity of the antioxidant enzymes, and the transcriptional levels of the immune related genes (IL-1beta, IFN-gamma and TNF-alpha) and stress proteins (HSP70 and MT) were enhanced in all treatments, except that of MT in the 12 mug/g Se(Y) group. In addition, both Se species inhibited the activity of acetylcholinesterase (AChE) in the brain and one digestive enzyme alpha-glucosidase (alpha-Glu) in the intestine at 12 mug/g. However, after 90 d, the effects on most biochemical markers were less pronounced, implying a possible acclimation after prolonged duration. The results demonstrate Se is beneficial to O. niloticus at low levels and toxic at elevated levels. The immunostimulation by Se might be greatly weakened after long term feeding Se-enriched feed. This study helps to better understand the effects of Se on the antioxidant and immune systems and to establish the optimal Se levels in the feed and duration for O. niloticus.
Title: A Probe for Fluorescence Detection of the Acetylcholinesterase Activity Based on Molecularly Imprinted Polymers Coated Carbon Dots Jia Z, Luo Y, Wen H, Huang S, Du X, Xue W Ref: Chem Pharm Bull (Tokyo), 67:795, 2019 : PubMed
This paper presents a new probe for fluorescence detection of the acetylcholinesterase (AChE) activity based on molecularly imprinted polymer (MIP) coated carbon dots (C-dots) composite. The C-dots were hydrothermally synthesized with grafted silica surface and sealed with molecularly imprinted polymers in silica pores (MIP@C-dots) in situ. Removed the original template molecules, the MIP@C-dots composite exhibits quite high selectivity for acetylthiocholine (ACh). With AChE, its substrate ACh will be hydrolyzed into thiocholine and the fluorescence signals exhibit a dramatic decrease at 465 nm, Under optimal conditions, the fluorescent probe shows sensitive responses to AChE in the range of 0.01-0.6 mU/mL. The detection limits of AChE are as low as 3 microU/mL. These experiments results validate the novel fluorescent probe based on MIP@C-dots composite, paving a new way to evaluation of AChE activity and Screening inhibitors.
Five new Lycopodium alkaloids, huperzine Y1 (1), huperzine Y2 (2), huperzine Y3 (3), (+)-huperzine Z (4a) and (-)-huperzine Z (4b) as well as ten known alkaloids (5-14) were isolated from Huperzia serrata. The structures of the new compounds were established using extensive spectroscopic (1D and 2D NMR, IR, and HRESIMS) and calculated electronic circular dichroism (ECD) methods. Compounds 4a and 4b were a pair of enantiomers successfully separated by chiral HPLC resolution. Compounds 2 and 3 indicated inhibitory activities against acetylcholinesterase with IC50 value of 57.1+/-1.6 and 32.7+/-1.0 muMu, respectively. However, no compound showed inhibitory effect on butyrocholinesterase at the concentration of 100 muMu.
A high-fat diet (HFD) causes obesity-associated morbidities involved in macroautophagy and chaperone-mediated autophagy (CMA). AMPK, the mediator of macroautophage, has been reported to be inactivated in HFD-caused renal injury. However, PAX2, the mediator for CMA, has not been reported in HFD-caused renal injury. Here we report that HFD-caused renal injury involved the inactivation of Pax2 and Ampk, and the activation of soluble epoxide hydrolase (sEH), in a murine model. Specifically, mice fed on an HFD for 2, 4, and 8 wk showed time-dependent renal injury, the significant decrease in renal Pax2 and Ampk at both mRNA and protein levels, and a significant increase in renal sEH at mRNA, protein, and molecular levels. Also, administration of an sEH inhibitor, 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl)urea, significantly attenuated the HFD-caused renal injury, decreased renal sEH consistently at mRNA and protein levels, modified the renal levels of sEH-mediated epoxyeicosatrienoic acids (EETs) and dihydroxyeicosatrienoic acids (DHETs) as expected, and increased renal Pax2 and Ampk at mRNA and/or protein levels. Furthermore, palmitic acid (PA) treatment caused significant increase in Mcp-1, and decrease in both Pax2 and Ampk in murine renal mesangial cells (mRMCs) time- and dose-dependently. Also, 14(15)-EET (a major substrate of sEH), but not its sEH-mediated metabolite 14,15-DHET, significantly reversed PA-induced increase in Mcp-1, and PA-induced decrease in Pax2 and Ampk. In addition, plasmid construction revealed that Pax2 may positively regulate Ampk transcriptionally in mRMCs. This study provides insights into and therapeutic target for the HFD-mediated renal injury.
Emerging data indicate that prenatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) could interfere with myogenic differentiation in vivo. Acetylcholinesterase (EC3.1.1.7; AChE), an enzyme critical for cholinergic neurotransmission, is abundantly expressed in neurons and mature myotubes, and we recently found that muscle AChE expression was suppressed in parallel with the inhibition of myogenic differentiation upon TCDD treatment in mouse C2C12cells. This TCDD-induced suppression of muscle AChE was proposed to involve an aryl hydrocarbon receptor (AhR)-independent mechanism, but the precise underlying mechanism remains unclear. Considering the widely recognized role of muscular activity in AChE expression and its potential crosstalk with the AhR signaling pathway, we sought to investigate the effect of TCDD on muscle AChE expression in the presence of muscular activity. Therefore, we employed a highly contractile rat primary skeletal muscle culture system in which AChE activity and the expression of genes related to it (AChE T subunit and collagen Q (ColQ)) were increased during the myogenic differentiation process. Although TCDD treatment successfully induced the expression of genes regulated by AhR activation, the treatment exerted no notable effects on myogenic differentiation. Moreover, muscle AChE enzymatic activity and mRNA level remained unchanged following TCDD treatment, and only ColQ mRNA expression was slightly increased after 4-day treatment with TCDD (10(-10)M). The compensatory role of muscle-contraction-related signaling pathways in this newly identified unresponsiveness of muscle AChE to TCDD warrants further investigation.
Six new pyrrole 2-carbaldehyde derived alkaloids, dahurines A-F (1-6), along with five known ones (7-11) and butyl 2-pyrrolidone-5-carboxylate (12) were isolated from the roots of Angelica dahurica. Their structures were determined by extensive spectroscopic and spectrometric data (1D and 2D NMR, IR, and HRESIMS) and calculated electronic circular dichroism (ECD) methods. Although compounds 7 and 8 have been chemically synthesized, they were obtained from natural materials for the first time. Compounds 2, 3, 4, 10, and 11 exhibited acetylcholinesterase inhibitory activity with IC50 values in the range of 47.5-52.5 muM. Pyrrole 2-carbaldehyde derived alkaloids from the roots of Angelica dahurica.
Title: Effects of astrocyte conditioned medium on neuronal AChE expression upon 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure Sha R, Chen Y, Luo Y, Liu YY, Xu L, Xie HQ, Zhao B Ref: Chemico-Biological Interactions, 309:108686, 2019 : PubMed
Acetylcholinesterase (EC3.1.1.7; AChE) is a key enzyme in the cholinergic system. Emerging evidence has shown that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a typical persistent organic pollutant, suppressed neuronal AChE activity via dysregulation of different biosynthesis processes in human and rat neuronal cells. In the nervous system, astrocytes protect neurons from environmental pollutants. As a known target cell of TCDD, the astrocyte might be involved in TCDD effects on neuronal AChE. Therefore, in the present study, we found astrocyte-derived conditioned medium (ACM) could induce AChE activity preferentially in mature neurons in the absence of TCDD. The enzymatic activity of AChE was generally decreased in cultured cortical neurons upon direct treatment with TCDD (0.003-0.01nM). This trend of changes in AChE activity was not significantly altered in immature neurons exposed to ACM produced in the presence of TCDD (TACM group), but reversed in mature neurons. Compared with effects of treatment with ACM plus TCDD (ACMT), a significant differential effect on AChE activity was found in the TACM group in response to TCDD treatment specifically in immature neurons, suggesting the presence of a TCDD-specific active component derived from the astrocyte. Inconsistent alterations in expression and enzymatic activities of the AChE T subunit (AChET) and the proline-rich membrane anchor (PRiMA) were found, suggesting that a mechanism of action beyond the transcriptional level might be involved. These data indicate that the astrocyte might play a protective role in TCDD-induced alterations of neuronal AChE in certain stages of differentiation.
Title: The Effect of Longwave Ultraviolet Light Radiation on Dendrolimus tabulaeformis Antioxidant and Detoxifying Enzymes Wang W, Gao C, Ren L, Luo Y Ref: Insects, 11:, 2019 : PubMed
Longwave ultraviolet (UVA) light, in the range of 315-400 nm, has been widely used as a light source in the light trapping of insect pests. Previous studies have demonstrated the oxidative stress and lethal effect of UV radiation on insects. In this study, we evaluated the influence of UVA radiation on the antioxidant and detoxifying enzymes of Dendrolimus tabulaeformis. We tested the contents of malondialdehyde (MDA), hydroxyl radical (.OH), hydrogen peroxide (H2O2), reduced glutathione (GSH), and oxidized glutathione (GSSH) following different exposure time periods of UVA light irradiation on D. tabulaeformis adults. In addition, we investigated how the activities of antioxidant and detoxifying enzymes responded to UVA radiation by determining the activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), polyphenol oxidase (PPO), glutathione S-transferase (GST), glutathione reductase (GR), acetylcholinesterase (AChE), carboxylesterase (CarE), alkaline phosphatase (ALP), and acid phosphatase (ACP). Adults were exposed to UVA light for different time periods (0, 5, 15, 30, 60, and 120 min). We found that exposure to UVA light for 5 min resulted in rapid variation in the activities of the antioxidant and detoxification enzyme systems. However, the antioxidant capacity of females was incongruous with that of males following UVA irradiation. Our results confirmed that UVA light irradiation increased the level of oxidative stress and disturbed physiological detoxification in D. tabulaeformis adults. Based on the above results, we anticipated that further research of the mechanism of UVA irradiation on the antioxidant and detoxifying enzymes of D. tabulaeformis would gain more importance, allowing to develop and use new, less toxic and environmentally friendly pesticides.
The current clinical symptomatic therapy for Alzheimer's disease involves increasing acetylcholine levels in the brain by inhibiting acetylcholinesterase. However, the effectiveness of acetylcholinesterase inhibitors decreases as the disease progresses, leading to many side effects including over-inhibition of other enzymes and hepatic injury. Herein, we investigate the effects of the direct delivery of a low-dose of acetylcholine via human serum albumin nanoparticles to brain. This novel nanodrug improved both spatial learning and memory capability, whereas it reduced oxidative damage in mice. More importantly, damage to the liver or interference with the inherent neurotransmitter generation due to supplementation were almost absent. Our study is the first to demonstrate that supplementation of acetylcholine-loaded nanoparticles might offer a better therapeutic option in the ease of Alzheimer's disease.
Title: Biosynthetic and antimicrobial potential of actinobacteria isolated from bulrush rhizospheres habitat in Zhalong Wetland, China Li Y, Li Q, Gao J, Wang J, Luo Y, Fan X, Gu P Ref: Arch Microbiol, 200:695, 2018 : PubMed
The wetland ecosystem is known to possess unique vegetation and serves multiple functions within the environment. In this study, bacterial bioprospecting of bulrush rhizospheres in the Zhalong Wetland, China, was performed using comprehensive methods, including strain isolation and phylogenetic analysis, PCR detection of biosynthetic gene clusters, assessment of antimicrobial activity, metabolite profiling and genome analysis. A total of 27 actinobacterial strains were isolated, and their biosynthetic gene clusters (NRPS, PKS-I and PKS-II) were investigated; all of the tested strains had at least one of the three aforementioned biosynthetic gene clusters. Furthermore, fermentation broth extracts produced by these strains showed antimicrobial activities against certain pathogens, and ten of the extracts exhibited broad-spectrum antimicrobial activity. Liquid chromatography-mass spectrometry (LC-MS) analysis indicated chemical diversity of secondary metabolites from these extracts. Among these strains, ZLSD-24 generated the largest amounts and types of secondary metabolites. Subsequent genome analysis showed that 41 secondary metabolite biosynthetic gene clusters were present in the strain ZLSD-24, which was in accordance with the LC-MS data. Taken together, the results of this study reveal that bulrush rhizosphere habitat in the Zhalong wetland is a promising source of novel natural products.
Title: Protein Crystallography and Site-Direct Mutagenesis Analysis of the Poly(ethylene terephthalate) Hydrolase PETase from Ideonella sakaiensis Liu B, He L, Wang L, Li T, Li C, Liu H, Luo Y, Bao R Ref: Chembiochem, 19:1471, 2018 : PubMed
Unlike traditional recycling strategies, biodegradation is a sustainable solution for disposing of poly(ethylene terephthalate) (PET) waste. PETase, a newly identified enzyme from Ideonella sakaiensis, has high efficiency and specificity towards PET and is, thus, a prominent candidate for PET degradation. On the basis of biochemical analysis, we propose that a wide substrate-binding pocket is critical for its excellent ability to hydrolyze crystallized PET. Structure-guided site-directed mutagenesis revealed an improvement in PETase catalytic efficiency, providing valuable insight into how the molecular engineering of PETase can optimize its application in biocatalysis.
Title: Omega-6 fatty acids down-regulate matrix metalloproteinase expression in a coronary heart disease-induced rat model Lu N, Du Y, Li H, Luo Y, Ouyang B, Chen Y, Yang Y, Yang L Ref: International Journal of Experimental Pathology, 99:210, 2018 : PubMed
The present study investigated the therapeutic potential of omega-6 fatty acids, according to their effects on antioxidant markers and matrix metalloproteinases (MMPs), in coronary heart disease-induced rats. Rats were grouped into group I (sham control), group II (control), group III (0.5 g/kg bwt of omega-6 fatty acids) and group IV (1 g/kg bwt of omega-6 fatty acids). Reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), reduced glutathione (GSH), catalase, glutathione peroxidase (Gpx) and acetylcholinesterase (AChE) enzyme activities were determined. ROS and MDA were substantially reduced, whereas SOD, catalase, Gpx and AChE were significantly increased, following supplementation with omega-6 fatty acids. MMP-2 mRNA expression was drastically increased by 95% in group II. Treatment significantly reduced MMP-2 mRNA expression by 12.3% and 26.7% in groups III and IV respectively. MMP-9 mRNA expression drastically increased, by 121%, in group II. Treatment significantly reduced MMP-9 mRNA expression by 22.6% and 29.4% in groups III and IV respectively. MMP-2 protein expression was drastically increased, by 81%, in group II. Treatment significantly reduced MMP-2 protein expression by 9.4% and 26% in groups III and IV respectively. MMP-9 protein expression was drastically increased, by 100%, in group II. Treatment significantly reduced MMP-9 protein expression by 18.9% and 26.9% in groups III and IV respectively. In summary, the consumption of omega-6 fatty acids significantly decreased MDA and ROS, while SOD, catalase, GHS, Gpx and AChE were increased. Furthermore, omega-6 fatty acids significantly downregulated MMP-2 and MMP-9 expression in our coronary heart disease-induced rat model.
Title: Soluble Epoxide Hydrolase Plays a Vital Role in Angiotensin II-Induced Lung Injury in Mice Tao W, Li PS, Xu G, Luo Y, Shu YS, Tao YZ, Yang LQ Ref: Shock, 50:589, 2018 : PubMed
BACKGROUND: Angiotensin II plays a vital role in the pathogenesis of acute respiratory distress syndrome (ARDS). However, its mechanism is not well defined. Angiotensin II upregulates the expression of soluble epoxide hydrolase (sEH; Ephx2). sEH is suggested as a potential pharmacologic target for ARDS. The present study investigates whether the sEH is involved in the angiotensin II-triggered pulmonary inflammation and edema using an angiotensin II-induced lung injury animal model. METHODS: Lung injury was induced by angiotensin II intratracheally instillation in wild-type or Ephx2 deficient mice. RESULTS: sEH activities were markedly increased in wild-type mice treated with angiotensin II. Angiotensin II markedly increased the levels of tumor necrosis factor-alpha and interleukin-1beta in bronchoalveolar lavage fluid, worsened alveolar capillary protein leak and lung histological alterations, and elevated activity of activator protein-1 and nuclear factor-kappaB. However, these changes were significantly improved in Ephx2 deficient mice. Moreover, Losartan, an angiotensin II receptor 1 antagonist, abolished the sEH induction and improved mortality. CONCLUSIONS: Angiotensin II-induced lung injury was improved in sEH gene deleted mice. The angiotensin II-triggered pulmonary inflammation is mediated, at least in part, through the sEH.
Dioxin-induced toxicities that affect the development of the motor system have been proposed since many years. However, cellular evidence and the molecular basis for the effects are limited. In this study, a cultured mouse myoblast cell line, C2C12, was utilized to examine the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on myogenic differentiation and expression of acetylcholinesterase (AChE), a neuromuscular transmission-related gene. The results showed that TCDD exposure at 10(-10)M repressed the myotube formation of C2C12cells by disturbing the fusion process and suppressing the expression of myosin heavy chain, a myobute structural protein, and not by induction of cytotoxicity. Furthermore, TCDD dose dependently suppressed the transcriptional expression and enzymatic activity of AChE during the myogenic differentiation, particularly in the middle stage. However, the administration of aryl hydrocarbon receptor antagonists, CH223191 and alpha-naphthoflavone, did not completely reverse the TCDD-induced downregulation of muscular AChE during myogenic differentiation. These findings suggest that low dose exposure to dioxin may result in disturbances of muscle differentiation and neuromuscular transmission.
Stroke commonly leads to adult disability and death worldwide. Its major symptoms are spastic hemiplegia and discordant motion, consequent to neuronal cell death induced by brain vessel occlusion. Acetylcholinesterase (AChE) is upregulated and allied with inflammation and apoptosis after stroke. Recent studies suggest that AChE inhibition ameliorates ischemia-reperfusion injury and has neuroprotective properties. (-)-Phenserine, a reversible AChE inhibitor, has a broad range of actions independent of its AChE properties, including neuroprotective ones. However, its protective effects and detailed mechanism of action in the rat middle cerebral artery occlusion model (MCAO) remain to be elucidated. This study investigated the therapeutic effects of (-)-phenserine for stroke in the rat focal cerebral ischemia model and oxygen-glucose deprivation/reperfusion (OGD/RP) damage model in SH-SY5Y neuronal cultures. (-)-Phenserine mitigated OGD/PR-induced SH-SY5Y cell death, providing an inverted U-shaped dose-response relationship between concentration and survival. In MCAO challenged rats, (-)-phenserine reduced infarction volume, cell death and improved body asymmetry, a behavioral measure of stoke impact. In both cellular and animal studies, (-)-phenserine elevated brain-derived neurotrophic factor (BDNF) and B-cell lymphoma 2 (Bcl-2) levels, and decreased activated-caspase 3, amyloid precursor protein (APP) and glial fibrillary acidic protein (GFAP) expression, potentially mediated through the ERK-1/2 signaling pathway. These actions mitigated neuronal apoptosis in the stroke penumbra, and decreased matrix metallopeptidase-9 (MMP-9) expression. In synopsis, (-)-phenserine significantly reduced neuronal damage induced by ischemia/reperfusion injury in a rat model of MCAO and cellular model of OGD/RP, demonstrating that its anti-apoptotic/neuroprotective/neurotrophic cholinergic and non-cholinergic properties warrant further evaluation in conditions of brain injury.
Title: Oxoisoaporphine alkaloid derivative 8-1 reduces Abeta1-42 secretion and toxicity in human cell and Caenorhabditis elegans models of Alzheimer's disease Huang L, Luo Y, Pu Z, Kong X, Fu X, Xing H, Wei S, Chen W, Tang H Ref: Neurochem Int, 108:157, 2017 : PubMed
Alzheimer's disease (AD) is a multifactorial neurodegenerative disease and a growing health problem worldwide. Because the drugs currently used to treat AD have certain drawbacks such as single targeting, there is a need to develop novel multi-target compounds, among which oxoisoaporphine alkaloid derivatives are promising candidates. In this study, the possible anti-AD activities of 14 novel oxoisoaporphine alkaloid derivatives that we synthesized were screened and evaluated. We found that, in the 14 novel derivatives, compound 8-1 significantly reduced Abeta1-42 secretion in SH-SY5Y cells overexpressing the Swedish mutant form of human beta-amyloid precursor protein (APPsw). Next, we found that compound 8-1 could down-regulate the expression level of beta-amyloid precursor protein (APP) in APPsw cells. Moreover, compound 8-1 significantly delayed paralysis in the Abeta1-42-transgenic Caenorhabditis elegans strain GMC101, which could be explained by the fact that compound 8-1 down-regulated acetylcholinesterase activity, protected against H2O2-induced acute oxidative stress and paraquat-induced chronic oxidative stress, and enhanced autophagy activity. Taken together, our data suggest that compound 8-1 could attenuate the onset and development of AD.
Title: Individual and binary mixture effects of bisphenol A and lignin-derived bisphenol in Daphnia magna under chronic exposure Li D, Chen H, Bi R, Xie H, Zhou Y, Luo Y, Xie L Ref: Chemosphere, 191:779, 2017 : PubMed
In recent years, many new chemicals have been synthesized from biomass with an aim for sustainable development by replacing the existing toxic chemicals with those having similar properties and applications. However, the effects of these new chemicals on aquatic organisms remain relatively unknown. In this study, the effects of bisphenol A (BPA) and lignin-derived bisphenol (LD-BP, a BPA analogue) on Daphnia magna were evaluated. The animals were exposed to BPA, LD-BP, and their binary mixture at concentrations (2-2000 mug L-1) for 21 days. The expression of various biochemical markers and the effects on growth, molting, and reproduction parameters were examined. The results showed that the weight of daphnids significantly increased after exposure to BPA, LD-BP, and the binary mixture relative to that of the control animals. The activity of superoxide dismutase was significantly inhibited by LD-BP and the binary mixture. At the highest exposure concentration of the binary mixture, the activities of acetylcholinesterase and alpha-glucosidase, fecundity, and the number of neonates per brood were significantly altered. Our results showed that the effects of BPA and LD-BP on D. magna were generally comparable, except for the effect on the weight at their environmentally relevant concentrations (e.g., <20 mug L-1). The effects on the reproduction of D. magna could be mainly due to the shift in energy redistribution under BPA and LD-BP exposures. Our results implied that exposures to both BPA and LD-BP could potentially cause deleterious effects at the population level in D. magna.
The Chinese formula Bushen-Yizhi (BSYZ) has been reported to ameliorate cognitive dysfunction. However the mechanism is still unclear. In this study, we employ an aging model, SAMP8 mice, to explore whether BSYZ could protect dementia through SIRT1/endoplasmic reticulum (ER) stress pathway. Morris water maze and the fearing condition test results show that oral administration of BSYZ (1.46 g/kg/d, 2.92 g/kg/d and 5.84 g/kg/d) and donepezil (3 mg/kg/d) shorten the escape latency, increase the crossing times of the original position of the platform and the time spent in the target quadrant, and increase the freezing time. BSYZ decreases the activity of acetylcholinesterase (AChE), and increases the activity of choline acetyltransferase (ChAT) and the concentration of acetylcholine (Ach) in both hippocampus and cortex. In addition, western blot results (Bcl-2, Bax and Caspase-3) and TUNEL staining show that BSYZ prevents neuron from apoptosis, and elevates the expression of neurotrophic factors, including nerve growth factor (NGF), postsynapticdensity 95 (PSD95) and synaptophysin (SYN), in both hippocampus and cortex. BSYZ also increases the protein expression of SIRT1 and alleviates ER stress-associated proteins (PERK, IRE-1alpha, eIF-2alpha, BIP, PDI and CHOP). These results indicate that the neuroprotective mechanism of BSYZ might be related with SIRT1/ER stress pathway.
Title: Accumulation and effects of Cr(VI) in Japanese medaka (Oryzias latipes) during chronic dissolved and dietary exposures Chen H, Mu L, Cao J, Mu J, Klerks PL, Luo Y, Guo Z, Xie L Ref: Aquat Toxicol, 176:208, 2016 : PubMed
Chromium (Cr) is an essential metal and a nutritional supplement for both human and agricultural uses. It is also a pollutant from a variety of industrial uses. These uses can lead to elevated Cr levels in aquatic environments, where it can enter and affect aquatic organisms. Its accumulation and subsequent effects in fish have received relatively little attention, especially for chronic exposure. In the present study, Japanese medaka were chronically exposed to dissolved or dietary Cr(VI) for 3 months. Cr accumulation in liver, gills, intestine, and brain was evaluated. Effects on the antioxidant system, nervous system (acetylcholinesterase, AChE), digestive system (alpha-glucosidase, alpha-Glu), and tissue histology (liver and gills) were also assessed. Cr accumulation was observed in the intestine and liver of fish exposed to Cr-contaminated brine shrimp. However, chronic dissolved Cr exposure led to significant Cr accumulation in all organs tested. Analysis of the subcellular distribution of Cr in medaka livers revealed that 37% of the Cr was present in the heat stable protein fraction. The dissolved Cr exposure had pronounced effects on the antioxidant system in the liver, with an elevated ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) and decreases in GSH and glutathione S-transferase (GST). The alpha-Glu activity in the intestine was significantly inhibited. In addition, Cr exposure caused histopathological alterations in the gills and liver. In general, the effects of dietary Cr were relatively minor, possible due to the much lower accumulation in the fish. Our results imply that Japanese medaka accumulate Cr mainly via uptake of dissolved Cr(VI).
Title: A systems pharmacology approach to decipher the mechanism of danggui-shaoyao-san decoction for the treatment of neurodegenerative diseases Luo Y, Wang Q, Zhang Y Ref: J Ethnopharmacol, 178:66, 2016 : PubMed
ETHNOPHARMACOLOGICAL RELEVANCE: Neurodegenerative diseases (NDs) is a time-dependent course for a sequence of conditions that primarily impact the neurons in the human brain, ultimately, resulting in persistence and progressive degeneration and / or death of nerve cells and reduction of cognition and memory function. Currently, there are no therapeutic approaches to cure neurodegeneration, except certain medicines that temporarily alleviate symptoms, facilitating the improvement of a patients' quality of life. Danggui-shaoyao-san (DSS), as a famous Chinese herbal formula, has been widely used in the treatment of various illnesses, including neurodegenerative diseases. Although well-practiced in clinical medicine, the mechanisms involved in DSS for the treatment of neurodegenerative diseases remain elusive. MATERIALS AND METHODS: In the present study, a novel systems pharmacology approach was developed to decipher the potential mechanism between DSS and neurodegenerative disorders, implicated in oral bioavailability screening, drug-likeness assessment, target identification and network analysis. RESULTS: Based on a comprehensive systems approach, active compounds of DSS, relevant potential targets and targets associated with diseases were predicted. Active compounds, targets and diseases were used to construct biological networks, such as, compound-target interactions and target-disease networks, to decipher the mechanisms of DSS to address NDs. CONCLUSIONS: Overall, a well-understood picture of DSS, hallmarked by multiple herbs-compounds-targets-pathway-cooperation networks for the treatment of NDs, was revealed. Notably, this systems pharmacology approach provided a novel in silico approach for the development paradigm of traditional Chinese medicine (TCM) and the generation of new strategies for the management of NDs.
Title: Antifeedant Activity of Ginkgo biloba Secondary Metabolites against Hyphantria cunea Larvae: Mechanisms and Applications Pan L, Ren L, Chen F, Feng Y, Luo Y Ref: PLoS ONE, 11:e0155682, 2016 : PubMed
Ginkgo biloba is a typical relic plant that rarely suffers from pest hazards. This study analyzed the pattern of G. biloba pest hazards in Beijing; tested the antifeedant activity of G. biloba extracts, including ginkgo flavonoids, ginkgolide, and bilobalide, against Hyphantria cunea larvae; determined the activities of glutathione transferase (GSTs), acetylcholinesterase (AChE), carboxylesterase (CarE) and mixed-functional oxidase (MFO), in larvae after feeding on these G. biloba secondary metabolites; and screened for effective botanical antifeedants in the field. In this study, no indicators of insect infestation were found for any of the examined leaves of G. biloba; all tested secondary metabolites showed significant antifeedant activity and affected the activity of the four larval detoxifying enzymes. Ginkgolide had the highest antifeedant activity and the most significant effect on the detoxifying enzymes (P<0.05). Spraying leaves with G. biloba extracts or ginkgolide both significantly repelled H. cunea larvae in the field (P<0.05), although the former is more economical and practical. This study investigated the antifeedant activity of G. biloba secondary metabolites against H. cunea larvae, and the results provide new insights into the mechanism of G. biloba pest resistance. This study also developed new applications of G. biloba secondary metabolites for effective pest control.
Traumatic brain injury (TBI), often caused by a concussive impact to the head, affects an estimated 1.7 million Americans annually. With no approved drugs, its pharmacological treatment represents a significant and currently unmet medical need. In our prior development of the anti-cholinesterase compound phenserine for the treatment of neurodegenerative disorders, we recognized that it also possesses non-cholinergic actions with clinical potential. Here, we demonstrate neuroprotective actions of phenserine in neuronal cultures challenged with oxidative stress and glutamate excitotoxicity, two insults of relevance to TBI. These actions translated into amelioration of spatial and visual memory impairments in a mouse model of closed head mild TBI (mTBI) two days following cessation of clinically translatable dosing with phenserine (2.5 and 5.0 mg/kg BID x 5 days initiated post mTBI) in the absence of anti-cholinesterase activity. mTBI elevated levels of thiobarbituric acid reactive substances (TBARS), a marker of oxidative stress. Phenserine counteracted this by augmenting homeostatic mechanisms to mitigate oxidative stress, including superoxide dismutase [SOD] 1 and 2, and glutathione peroxidase [GPx], the activity and protein levels of which were measured by specific assays. Microarray analysis of hippocampal gene expression established that large numbers of genes were exclusively regulated by each individual treatment with a substantial number of them co-regulated between groups. Molecular pathways associated with lipid peroxidation were found to be regulated by mTBI, and treatment of mTBI animals with phenserine effectively reversed injury-induced regulations in the 'Blalock Alzheimer's Disease Up' pathway. Together these data suggest that multiple phenserine-associated actions underpin this compound's ability to ameliorate cognitive deficits caused by mTBI, and support the further evaluation of the compound as a therapeutic for TBI.
In the brain, AMPA-type glutamate receptors are major postsynaptic receptors at excitatory synapses that mediate fast neurotransmission and synaptic plasticity. alpha/beta-Hydrolase domain-containing 6 (ABHD6), a monoacylglycerol lipase, was previously found to be a component of AMPA receptor macromolecular complexes, but its physiological significance in the function of AMPA receptors (AMPARs) has remained unclear. The present study shows that overexpression of ABHD6 in neurons drastically reduced excitatory neurotransmission mediated by AMPA but not by NMDA receptors at excitatory synapses. Inactivation of ABHD6 expression in neurons by either CRISPR/Cas9 or shRNA knockdown methods significantly increased excitatory neurotransmission at excitatory synapses. Interestingly, overexpression of ABHD6 reduced glutamate-induced currents and the surface expression of GluA1 in HEK293T cells expressing GluA1 and stargazin, suggesting a direct functional interaction between these two proteins. The C-terminal tail of GluA1 was required for the binding between of ABHD6 and GluA1. Mutagenesis analysis revealed a GFCLIPQ sequence in the GluA1 C terminus that was essential for the inhibitory effect of ABHD6. The hydrolase activity of ABHD6 was not required for the effects of ABHD6 on AMPAR function in either neurons or transfected HEK293T cells. Thus, these findings reveal a novel and unexpected mechanism governing AMPAR trafficking at synapses through ABHD6.
Rannasangpei (RSNP) is used as a therapeutic agent in the treatment of cardiovascular diseases, neurological disorders, and neurodegeneration in China; however, its potential use in the treatment of vascular dementia (VD) was unclear. In this study, our aim was to examine the neuroprotective effect of RSNP in a VD rat model, which was induced by permanent bilateral common carotid artery occlusion (2VO). Four-week administration with two doses of RSNP was investigated in our study. Severe cognitive deficit in the VD model, which was confirmed in Morris water maze (MWM) test, was significantly restored by the administration of RSNP. ELISA revealed that the treatments with both doses of RSNP could reinstate the cholinergic activity in the VD animals by elevating the production of choline acetyltransferase (ChAT) and reducing the acetylcholinesterase (AChE); the treatment of RSNP could also reboot the level of superoxide dismutase (SOD) and decrease malondialdehyde (MDA). Moreover, Western blot and quantitative PCR (Q-PCR) results indicated that the RSNP could suppress the apoptosis in the hippocampus of the VD animals by increasing the expression ratio of B-cell lymphoma-2 (Bcl-2) to Bcl-2-associated X protein (Bax). These results suggested that RSNP might be a therapeutic agent in the treatment of vascular dementia in the future.
Title: Rapid-releasing of HI-6 via brain-targeted mesoporous silica nanoparticles for nerve agent detoxification Yang J, Fan L, Wang F, Luo Y, Sui X, Li W, Zhang X, Wang Y Ref: Nanoscale, 8:9537, 2016 : PubMed
The toxic nerve agent (NA) soman is the most toxic artificially synthesized compound that can rapidly penetrate into the brain and irreversibly inhibit acetylcholinesterase (AChE) activity, leading to immediate death. However, there are currently few brain-targeted nanodrugs that can treat acute chemical brain poisoning owing to the limited drug-releasing speed. The present study investigated the effectiveness of a nanodrug against NA toxicity that has high blood-brain barrier penetration and is capable of rapid drug release. Transferrin-modified mesoporous silica nanoparticles (TF-MSNs) were conjugated with the known AChE reactivator HI-6. This nanodrug rapidly penetrated the blood-brain barrier in zebrafish and mice and restored cerebral AChE activity via the released HI-6, preventing the brain damage caused by soman poisoning and increasing the survival rate in mice. Furthermore, there was no toxicity associated with the MSNs in mice or rats. These results demonstrate that TF-MSNs loaded with HI-6 represent the most effective antidote against NA poisoning by soman reported to date, and suggest that MSNs are a safe alternative to conventional drugs and an optimal nanocarrier for treating brain poisoning, which requires acute pulse cerebral administration.
Title: Design, synthesis and evaluation of scutellarein-O-alkylamines as multifunctional agents for the treatment of Alzheimer's disease Sang Z, Qiang X, Li Y, Yuan W, Liu Q, Shi Y, Ang W, Luo Y, Tan Z, Deng Y Ref: Eur Journal of Medicinal Chemistry, 94:348, 2015 : PubMed
A series of scutellarein-O-alkylamine derivatives were designed, synthesized and tested as multifunctional agents for the treatment of Alzheimer's disease (AD). The results showed that most of these compounds exhibited good multifunctional activities. Among them, compound 16d demonstrated significant metal chelating properties, moderate acetylcholinesterase (AChE) inhibitory and anti-oxidative activity, and excellent inhibitory effects on self-induced Abeta1-42 aggregation, Cu2+-induced Abeta1-42 aggregation, human AChE-induced Abeta1-40 aggregation and disassembled Cu2+-induced aggregation of the well-structured Abeta1-42 fibrils. Both kinetic analysis of AChE inhibition and molecular modeling study suggested that 16d binds simultaneously to the catalytic active site and peripheral anionic site of AChE. Moreover, compound 16d showed a good protective effect against H2O2-induced PC12 cell injury, with low toxicity in SH-SY5Y cells. Furthermore, the step-down passive avoidance test showed this compound significantly reversed scopolamine-induced memory deficit in mice. Thus, 16d was shown to be an interesting multifunctional lead compound worthy of further study.
Next-generation sequencing is being evaluated for use with food-borne illness investigations, especially when the outbreak strains produce patterns that cannot be discriminated from non-outbreak strains using conventional procedures. Here we report complete genome assemblies of two Salmonella enterica serovar Heidelberg strains with a common pulsed-field gel electrophoresis pattern isolated during an outbreak investigation.
Salmonella enterica subsp. enterica serovar Heidelberg (S. Heidelberg) is one of the top serovars causing human salmonellosis. Recently, an antibiotic-resistant strain of this serovar was implicated in a large 2011 multistate outbreak resulting from consumption of contaminated ground turkey that involved 136 confirmed cases, with one death. In this study, we assessed the evolutionary diversity of 44 S. Heidelberg isolates using whole-genome sequencing (WGS) generated by the 454 GS FLX (Roche) platform. The isolates, including 30 with nearly indistinguishable (one band difference) Xbal pulsed-field gel electrophoresis patterns (JF6X01.0032, JF6X01.0058), were collected from various sources between 1982 and 2011 and included nine isolates associated with the 2011 outbreak. Additionally, we determined the complete sequence for the chromosome and three plasmids from a clinical isolate associated with the 2011 outbreak using the Pacific Biosciences (PacBio) system. Using single-nucleotide polymorphism (SNP) analyses, we were able to distinguish highly clonal isolates, including strains isolated at different times in the same year. The isolates from the recent 2011 outbreak clustered together with a mean SNP variation of only 17 SNPs. The S. Heidelberg isolates carried a variety of phages, such as prophage P22, P4, lambda-like prophage Gifsy-2, and the P2-like phage which carries the sopE1 gene, virulence genes including 62 pathogenicity, and 13 fimbrial markers and resistance plasmids of the incompatibility (Inc)I1, IncA/C, and IncHI2 groups. Twenty-one strains contained an IncX plasmid carrying a type IV secretion system. On the basis of the recent and historical isolates used in this study, our results demonstrated that, in addition to providing detailed genetic information for the isolates, WGS can identify SNP targets that can be utilized for differentiating highly clonal S. Heidelberg isolates.
As an economic crop, pepper satisfies people's spicy taste and has medicinal uses worldwide. To gain a better understanding of Capsicum evolution, domestication, and specialization, we present here the genome sequence of the cultivated pepper Zunla-1 (C. annuum L.) and its wild progenitor Chiltepin (C. annuum var. glabriusculum). We estimate that the pepper genome expanded approximately 0.3 Mya (with respect to the genome of other Solanaceae) by a rapid amplification of retrotransposons elements, resulting in a genome comprised of approximately 81% repetitive sequences. Approximately 79% of 3.48-Gb scaffolds containing 34,476 protein-coding genes were anchored to chromosomes by a high-density genetic map. Comparison of cultivated and wild pepper genomes with 20 resequencing accessions revealed molecular footprints of artificial selection, providing us with a list of candidate domestication genes. We also found that dosage compensation effect of tandem duplication genes probably contributed to the pungent diversification in pepper. The Capsicum reference genome provides crucial information for the study of not only the evolution of the pepper genome but also, the Solanaceae family, and it will facilitate the establishment of more effective pepper breeding programs.
Title: Whole Genome Sequence of the Probiotic Strain Lactobacillus paracasei N1115, Isolated from Traditional Chinese Fermented Milk Wang S, Zhu H, He F, Luo Y, Kang Z, Lu C, Feng L, Lu X, Xue Y, Wang H Ref: Genome Announc, 2:, 2014 : PubMed
Lactobacillus paracasei N1115 is a new strain with probiotic properties isolated from traditional homemade dairy products in Inner Mongolia, China. Here, we report the complete genome sequence of L. paracasei N1115, which shows high similarity to the well-studied probiotic Lactobacillus rhamnosus GG, and 3 structures turned out to be inversions, according to the colinearity analysis of the BLAST alignment.
Title: New efficient imidazolium aldoxime reactivators for nerve agent-inhibited acetylcholinesterase Wei Z, Liu YQ, Zhou XB, Luo Y, Huang CQ, Wang YA, Zheng ZB, Li S Ref: Bioorganic & Medicinal Chemistry Lett, 24:5743, 2014 : PubMed
Herein, we described a new class of uncharged non-pyridinium reactivators for nerve agent-inhibited acetylcholinesterase (AChE). Based on a dual site binding strategy, we conjugated the imidazolium aldoxime to different peripheral site ligands (PSLs) of AChE through alkyl chains. Compared with the known quaternary pyridinium reactivators, two of the resulting conjugates (7g and 7h) were highlighted to be the first efficient non-pyridinium oxime conjugates exhibiting similar or superior ability to reactivate sarin-, VX- and tabun-inhibited AChE. Moreover, they were more broad-spectrum reactivators.
Facile laboratory tools are needed to augment identification in contamination events to trace the contamination back to the source (traceback) of Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis). Understanding the evolution and diversity within and among outbreak strains is the first step towards this goal. To this end, we collected 106 new S. Enteriditis isolates within S. Enteriditis Pulsed-Field Gel Electrophoresis (PFGE) pattern JEGX01.0004 and close relatives, and determined their genome sequences. Sources for these isolates spanned food, clinical and environmental farm sources collected during the 2010 S. Enteritidis shell egg outbreak in the United States along with closely related serovars, S. Dublin, S. Gallinarum biovar Pullorum and S. Gallinarum. Despite the highly homogeneous structure of this population, S. Enteritidis isolates examined in this study revealed thousands of SNP differences and numerous variable genes (n = 366). Twenty-one of these genes from the lineages leading to outbreak-associated samples had nonsynonymous (causing amino acid changes) changes and five genes are putatively involved in known Salmonella virulence pathways. While chromosome synteny and genome organization appeared to be stable among these isolates, genome size differences were observed due to variation in the presence or absence of several phages and plasmids, including phage RE-2010, phage P125109, plasmid pSEEE3072_19 (similar to pSENV), plasmid pOU1114 and two newly observed mobile plasmid elements pSEEE1729_15 and pSEEE0956_35. These differences produced modifications to the assembled bases for these draft genomes in the size range of approximately 4.6 to 4.8 mbp, with S. Dublin being larger ( approximately 4.9 mbp) and S. Gallinarum smaller (4.55 mbp) when compared to S. Enteritidis. Finally, we identified variable S. Enteritidis genes associated with virulence pathways that may be useful markers for the development of rapid surveillance and typing methods, potentially aiding in traceback efforts during future outbreaks involving S. Enteritidis PFGE pattern JEGX01.0004.
We report a closed genome of Salmonella enterica subsp. enterica serovar Javiana (S. Javiana). This serotype is a common food-borne pathogen and is often associated with fresh-cut produce. Complete (finished) genome assemblies will support pilot studies testing the utility of next-generation sequencing (NGS) technologies in public health laboratories.
Shiga toxin-producing Escherichia coli (STEC) causes severe illness in humans, including hemorrhagic colitis and hemolytic uremic syndrome. A parallel evolutionary model was proposed in which E. coli strains of distinct phylogenies independently integrate Shiga toxin-encoding genes and evolve into STEC. We report the draft genomes of two emerging non-O157 STEC strains.
Salmonella enterica is recognized as one of the most common bacterial agents of foodborne illness. We report draft genomes of four Salmonella serovar Heidelberg isolates associated with the recent multistate outbreak of human Salmonella Heidelberg infections linked to kosher broiled chicken livers in the United States in 2011. Isolates 2011K-1259 and 2011K-1232 were recovered from humans, whereas 2011K-1724 and 2011K-1726 were isolated from chicken liver. Whole genome sequence analysis of these isolates provides a tool for studying the short-term evolution of these epidemic clones and can be used for characterizing potentially new virulence factors.
Title: Rape (Brassica chinensis L.) seed germination, seedling growth, and physiology in soil polluted with di-n-butyl phthalate and bis(2-ethylhexyl) phthalate Ma T, Christie P, Teng Y, Luo Y Ref: Environ Sci Pollut Res Int, 20:5289, 2013 : PubMed
Phthalic acid esters (PAEs) pollution in agricultural soils caused by widely employed plastic products is becoming more and more widespread in China. PAEs polluted soil can lead to phytotoxicity in higher plants and potential health risks to human being. We evaluated the individual toxicity of di-n-butyl phthalate (DnBP) and bis(2-ethylhexyl) phthalate (DEHP), two representative PAEs, to sown rape (Brassica chinensis L.) seeds within 72 h (as germination stage) and seedlings after germination for 14 days by monitoring responses and trends of different biological parameters. No significant effects of six concentrations of PAE ranging from 0 (not treated/NT) to 500 mg kg(-1) on germination rate in soil were observed. However, root length, shoot length, and biomass (fresh weight) were inhibited by both pollutants (except root length and biomass under DEHP). Stimulatory effects of both target pollutants on malondialdehyde (MDA) content, superoxide dismutase (SODase) activity, ascorbate peroxidase (APXase) content, and polyphenoloxidase (PPOase) activity in shoots and roots (SODase activity in shoots excluded) were in the same trend with the promotion of proline (Pro) but differed with acetylcholinesterase activity (except in shoots under DnBP) for analyzed samples treated for 72 h and 14 days. Responses of representative storage compounds free amino acids (FAA) and total soluble sugar (TSS) under both PAEs were raised. Sensitivity of APXase and Pro in roots demonstrates their possibility in estimation of PAE phytotoxicity and the higher toxicity of DnBP, which has also been approved by the morphological photos of seedlings at day 14. Higher sensitivity of the roots was also observed. The recommended soil allowable concentration is 5 mg DnBP kg(-1) soil for the development of rape. We still need to know the phytotoxicity of DEHP at whole seedling stage for both the growing and development; on the other hand, soil criteria for PAE compounds are urgently required in China.
Tapeworms (Cestoda) cause neglected diseases that can be fatal and are difficult to treat, owing to inefficient drugs. Here we present an analysis of tapeworm genome sequences using the human-infective species Echinococcus multilocularis, E. granulosus, Taenia solium and the laboratory model Hymenolepis microstoma as examples. The 115- to 141-megabase genomes offer insights into the evolution of parasitism. Synteny is maintained with distantly related blood flukes but we find extreme losses of genes and pathways that are ubiquitous in other animals, including 34 homeobox families and several determinants of stem cell fate. Tapeworms have specialized detoxification pathways, metabolism that is finely tuned to rely on nutrients scavenged from their hosts, and species-specific expansions of non-canonical heat shock proteins and families of known antigens. We identify new potential drug targets, including some on which existing pharmaceuticals may act. The genomes provide a rich resource to underpin the development of urgently needed treatments and control.
One new compound named amauroamoienin (1), together with thirteen known compounds (2-14), was isolated from the EtOAc extract of Amauroderma amoiensis. The structures of these compounds were elucidated by the analysis of 1D and 2D spectroscopic data and the MS technique. The bioassays of inhibitory activities of these isolates against acetylcholinesterase were evaluated, and compounds 1, 3, and 5 exhibited acetylcholinesterase inhibitory activities.
BACKGROUND: Next-Generation Sequencing (NGS) is increasingly being used as a molecular epidemiologic tool for discerning ancestry and traceback of the most complicated, difficult to resolve bacterial pathogens. Making a linkage between possible food sources and clinical isolates requires distinguishing the suspected pathogen from an environmental background and placing the variation observed into the wider context of variation occurring within a serovar and among other closely related foodborne pathogens. Equally important is the need to validate these high resolution molecular tools for use in molecular epidemiologic traceback. Such efforts include the examination of strain cluster stability as well as the cumulative genetic effects of sub-culturing on these clusters. Numerous isolates of S. Montevideo were shot-gun sequenced including diverse lineage representatives as well as numerous replicate clones to determine how much variability is due to bias, sequencing error, and or the culturing of isolates. All new draft genomes were compared to 34 S. Montevideo isolates previously published during an NGS-based molecular epidemiological case study. RESULTS: Intraserovar lineages of S. Montevideo differ by thousands of SNPs, that are only slightly less than the number of SNPs observed between S. Montevideo and other distinct serovars. Much less variability was discovered within an individual S. Montevideo clade implicated in a recent foodborne outbreak as well as among individual NGS replicates. These findings were similar to previous reports documenting homopolymeric and deletion error rates with the Roche 454 GS Titanium technology. In no case, however, did variability associated with sequencing methods or sample preparations create inconsistencies with our current phylogenetic results or the subsequent molecular epidemiological evidence gleaned from these data. CONCLUSIONS: Implementation of a validated pipeline for NGS data acquisition and analysis provides highly reproducible results that are stable and predictable for molecular epidemiological applications. When draft genomes are collected at 15x-20x coverage and passed through a quality filter as part of a data analysis pipeline, including sub-passaged replicates defined by a few SNPs, they can be accurately placed in a phylogenetic context. This reproducibility applies to all levels within and between serovars of Salmonella suggesting that investigators using these methods can have confidence in their conclusions.
Salmonellosis is a major contributor to the global public health burden. Salmonella enterica serotype Newport has ranked among three Salmonella serotypes most commonly associated with food-borne outbreaks in the United States. It was thought to be polyphyletic and composed of independent lineages. Here we report draft genomes of eight strains of S. Newport from diverse hosts and locations.
Salmonella enterica serovar Heidelberg has caused numerous outbreaks in humans. Here, we report draft genomes of five isolates of serovar Heidelberg associated with the recent (2011) multistate outbreak linked to ground turkey in the United States. Isolates 2011K-1110 and 2011K-1132 were recovered from humans, while isolates 2011K-1138, 2011K-1224, and 2011K-1225 were recovered from ground turkey. Whole-genome sequence analysis of these isolates provides a tool for studying the short-term evolution of these epidemic clones.
Non-O157 Shiga toxin-producing Escherichia coli (STEC) strains are emerging food-borne pathogens causing life-threatening diseases and food-borne outbreaks. A better understanding of their evolution provides a framework for developing tools to control food safety. We obtained 15 genomes of non-O157 STEC strains, including O26, O111, and O103 strains. Phylogenetic trees revealed a close relationship between O26:H11 and O111:H11 and a scattered distribution of O111. We hypothesize that STEC serotypes with the same H antigens might share common ancestors.
Salmonella enterica subsp. enterica serovar Enteritidis is a common food-borne pathogen, often associated with shell eggs and poultry. Here, we report draft genomes of 21 S. Enteritidis strains associated with or related to the U.S.-wide 2010 shell egg recall. Eleven of these genomes were from environmental isolates associated with the egg outbreak, and 10 were reference isolates from previous years, unrelated to the outbreak. The whole-genome sequence data for these 21 human pathogen strains are being released in conjunction with the newly formed 100K Genome Project.
Title: Proteomic response of wheat embryos to fosthiazate stress in a protected vegetable soil Yin C, Teng Y, Luo Y, Christie P Ref: J Environ Sci (China), 24:1843, 2012 : PubMed
A proteomic analysis of wheat defense response induced by the widely used organophosphorus nematicide fosthiazate is reported. Seed germination and two-dimensional gel electrophoresis (2-DE) experiments were performed using a Chinese wheat cultivar, Zhenmai No. 5. Root and shoot elongation decreased but thiobarbituric acid reactive substances (TBARS) content in embryos increased with increasing pesticide concentration. More than 1000 protein spots were reproducibly detected in each silver-stained gel. Thirty-seven protein spots with at least 2-fold changes were identified using MALDI-TOF MS/MS analysis. Of these, 24 spots were up-regulated and 13 were down-regulated. Proteins identified included some well-known classical stress responsive proteins under abiotic or biotic stresses as well as some unusual responsive proteins. Ten responsive proteins were reported for the first time at the proteomic level, including fatty acyl CoA reductase, dihydrodipicolinate synthase, DEAD-box ATPase-RNA-helicase, fimbriata-like protein, waxy B1, rust resistance kinase Lr10, putative In2.1 protein, retinoblastoma-related protein 1, pollen allergen-like protein and S-adenosyl-L-methionine:phosphoethanolamine N-methyltransferase. The proteins identified were involved in several processes such as metabolism, defense/detoxification, cell structure/cell growth, signal transduction/transcription, photosynthesis and energy. Seven candidate proteins were further analyzed at the mRNA level by RT-PCR to compare transcript and protein accumulation patterns, revealing that not all the genes were correlated well with the protein level. Identification of these responsive proteins may provide new insight into the molecular basis of the fosthiazate-stress response in the early developmental stages of plants and may be useful in stress monitoring or stress-tolerant crop breeding for environmentally friendly agricultural production.
Title: Tin (IV) chloride-promoted one-pot synthesis of novel tacrine analogues Hu H, Song L, Fang Q, Zheng J, Meng Z, Luo Y Ref: Molecules, 16:1878, 2011 : PubMed
A facile synthesis of potential acetylcholinesterase (AChE) inhibitors, the tacrine analogues 3a-p, has been accomplished by direct cyclocondensation of 1-aryl-4-cyano-5-aminopyrazole with beta-ketoesters using tin(IV) chloride as catalyst. The structures of all the compounds have been confirmed by IR, (1)H- and (1)(3)C-NMR.
The Salmonella enterica serovar Typhimurium strain UK-1 exhibits the highest invasion and virulence attributes among the most frequently studied strains. S. Typhimurium UK-1 has been used as the foundation for developing recombinant vaccines and has been used extensively on virulence and colonization studies in chickens and mice. We describe here the complete genome sequence of S. Typhimurium UK-1. Comparative genomics of Salmonella Typhimurium will provide insight into factors that determine virulence and invasion.
Nematode-trapping fungi are "carnivorous" and attack their hosts using specialized trapping devices. The morphological development of these traps is the key indicator of their switch from saprophytic to predacious lifestyles. Here, the genome of the nematode-trapping fungus Arthrobotrys oligospora Fres. (ATCC24927) was reported. The genome contains 40.07 Mb assembled sequence with 11,479 predicted genes. Comparative analysis showed that A. oligospora shared many more genes with pathogenic fungi than with non-pathogenic fungi. Specifically, compared to several sequenced ascomycete fungi, the A. oligospora genome has a larger number of pathogenicity-related genes in the subtilisin, cellulase, cellobiohydrolase, and pectinesterase gene families. Searching against the pathogen-host interaction gene database identified 398 homologous genes involved in pathogenicity in other fungi. The analysis of repetitive sequences provided evidence for repeat-induced point mutations in A. oligospora. Proteomic and quantitative PCR (qPCR) analyses revealed that 90 genes were significantly up-regulated at the early stage of trap-formation by nematode extracts and most of these genes were involved in translation, amino acid metabolism, carbohydrate metabolism, cell wall and membrane biogenesis. Based on the combined genomic, proteomic and qPCR data, a model for the formation of nematode trapping device in this fungus was proposed. In this model, multiple fungal signal transduction pathways are activated by its nematode prey to further regulate downstream genes associated with diverse cellular processes such as energy metabolism, biosynthesis of the cell wall and adhesive proteins, cell division, glycerol accumulation and peroxisome biogenesis. This study will facilitate the identification of pathogenicity-related genes and provide a broad foundation for understanding the molecular and evolutionary mechanisms underlying fungi-nematodes interactions.
Title: Cellulosilyticum ruminicola, a newly described rumen bacterium that possesses redundant fibrolytic-protein-encoding genes and degrades lignocellulose with multiple carbohydrate- borne fibrolytic enzymes Cai S, Li J, Hu FZ, Zhang K, Luo Y, Janto B, Boissy R, Ehrlich G, Dong X Ref: Applied Environmental Microbiology, 76:3818, 2010 : PubMed
Cellulosilyticum ruminicola H1 is a newly described bacterium isolated from yak (Bos grunniens) rumen and is characterized by its ability to grow on a variety of hemicelluloses and degrade cellulosic materials. In this study, we performed the whole-genome sequencing of C. ruminicola H1 and observed a comprehensive set of genes encoding the enzymes essential for hydrolyzing plant cell wall. The corresponding enzymatic activities were also determined in strain H1; these included endoglucanases, cellobiohydrolases, xylanases, mannanase, pectinases, and feruloyl esterases and acetyl esterases to break the interbridge cross-link, as well as the enzymes that degrade the glycosidic bonds. This bacterium appears to produce polymer hydrolases that act on both soluble and crystal celluloses. Approximately half of the cellulytic activities, including cellobiohydrolase (50%), feruloyl esterase (45%), and one third of xylanase (31%) and endoglucanase (36%) activities were bound to cellulosic fibers. However, only a minority of mannase (6.78%) and pectinase (1.76%) activities were fiber associated. Strain H1 seems to degrade the plant-derived polysaccharides by producing individual fibrolytic enzymes, whereas the majority of polysaccharide hydrolases contain carbohydrate-binding module. Cellulosome or cellulosomelike protein complex was never isolated from this bacterium. Thus, the fibrolytic enzyme production of strain H1 may represent a different strategy in cellulase organization used by most of other ruminal microbes, but it applies the fungal mode of cellulose production.
Title: Characterization of the tautomycetin biosynthetic gene cluster from Streptomyces griseochromogenes provides new insight into dialkylmaleic anhydride biosynthesis Li W, Luo Y, Ju J, Rajski SR, Osada H, Shen B Ref: Journal of Natural Products, 72:450, 2009 : PubMed
Tautomycetin (TTN) is a highly potent and specific protein phosphatase inhibitor isolated from Streptomyces griseochromogenes. The biological activity of TTN makes it an important lead for drug discovery, whereas its rare dialkylmaleic anhydride moiety and structural similarity to tautomycin (TTM), another potent phosphatase inhibitor with tremendous medicinal potential, draws attention to novel biosynthetic chemistries responsible for its production. To elucidate the biosynthetic machinery associated with TTN production, the ttn biosynthetic gene cluster from S. griseochromogenes was isolated and characterized, and its involvement in TTN biosynthesis confirmed by gene inactivation and complementation experiments. The ttn cluster was localized to a 79 kb DNA region, consisting of 19 open reading frames that encode two modular type I polyketide synthases (TtnAB), one type II thioesterase (TtnH), eight proteins for dialkylmaleic anhydride biosynthesis (TtnKLMNOPRS), four tailoring enzymes (TtnCDFI), two regulatory proteins (TtnGQ), and one resistance protein (TtnJ). A model for TTN biosynthesis is proposed on the basis of functional assignments from sequence analysis, which agrees well with previous feeding experiments, has been supported by in vivo gene inactivation experiments, and is supported by analogy to the recently reported ttm cluster. These findings set the stage to fully investigate TTN biosynthesis and to biosynthetically engineer new TTN analogues.
Title: Multimedia transport and risk assessment of organophosphate pesticides and a case study in the northern San Joaquin Valley of California Luo Y, Zhang M Ref: Chemosphere, 75:969, 2009 : PubMed
This paper presents a framework for cumulative risk characterization of human exposure to pesticides through multiple exposure pathways. This framework is illustrated through a case study of selected organophosphate (OP) pesticides in the northern San Joaquin Valley of California. Chemical concentrations in environmental media were simulated using a multimedia environmental fate model, and converted to contamination levels in exposure media. The risk characterization in this study was based on a residential-scale exposure to residues of multiple pesticides through everyday activities. Doses from a mixture of OP pesticides that share a common mechanism of toxicity were estimated following US Environmental Protection Agency guidelines for cumulative risk analysis. Uncertainty in the human exposure parameters was included in the Monte Carlo simulation in order to perform stochastic calculations for intakes and corresponding risks of OP pesticides. Risk of brain acetylcholinesterase inhibition was reported as margins of exposure (MOEs) of the 99.9th population percentile for two age groups living in the northern San Joaquin Valley during 1992-2005. Diet was identified as the dominant exposure pathway in cumulative exposure and risk, while the temporal trend and spatial variation in total MOE levels were associated with exposures to contaminated drinking water and ambient air. Uniformly higher risks were observed for children because of their greater inhalation and ingestion rates per body weight, relative to adults. The results indicated that exposures for children were about twice of those estimated for adults. Concerns over children's exposure to OP pesticide through food and water ingestion were suggested based on the spatiotemporal variations predicted for the subchronic MOEs at the 99.9th percentile of exposure in the study area.
Title: Protective effects of icariin on cognitive deficits induced by chronic cerebral hypoperfusion in rats Xu RX, Wu Q, Luo Y, Gong QH, Yu LM, Huang XN, Sun AS, Shi JS Ref: Clinical & Experimental Pharmacology & Physiology, 36:810, 2009 : PubMed
1. Icariin is a major constituent of flavonoids derived from the Chinese medicinal herb Epimedium revicornum Maxim. The aim of the present study was to investigate whether icariin has protective effects on learning ability and memory in a rat model of chronic cerebral hypoperfusion. 2. Chronic cerebral hypoperfusion was induced by permanent ligation of the common carotid artery in Wistar rats for 4 months. One month after permanent artery occlusion, rats were adminitered icariin at doses of 0, 30, 60 or 120 mg/kg per day, p.o., for 3 months. Neurobehavioural and neurobiochemical parameters were examined to evaluate the effects of icariin on cognitive deficits induced by chronic cerebral hypoperfusion. 3. The Morris water maze test revealed that learning ability and memory were severely impaired in untreated rats, but were significantly improved in icariin-treated rats. Icariin treatment also ameliorated chronic cerebral hypoperfusion-induced oxidative stress in the brain, as evidenced by reduced malondialdehyde formation and maintained superoxide dismutase activity. In addition, the decreased hippocampal levels of acetylcholine, acetylcholinesterase and choline acetyltransferase associated with chronic cerebral hypoperfusion were significantly prevented by icariin treatment. 4. In conclusion, icariin protects against cognitive deficits induced by chronic cerebral hypoperfusion in rats. These effects appear to be mediated through its anti-oxidant effects, as well as its effects on the circulatory and cholinergic systems.
Title: Toxic effects of chlorpromazine on Carassius auratus and its oxidative stress Li T, Zhou Q, Zhang N, Luo Y Ref: J Environ Sci Health B, 43:638, 2008 : PubMed
Under laboratory conditions, ecotoxicological effects of chlorpromazine (CPZ) on freshwater goldfish (Carassius auratus) were examined using the toxic culture experiment. The results showed that the median lethal concentration (LC(50)) of CPZ toxic to Carassius auratus in 24, 48 and 96 h was 1.11, 0.43 and 0.32 mg/L, respectively. Thus, CPZ is an extreme toxicant to goldfish. Furthermore, there were significantly positive correlations between the ecotoxicological effects of CPZ and its concentrations, and the toxicity became higher as the exposure time increased. The activity of superoxide dismutase (SOD) and catalase (CAT) in goldfish livers was significantly influenced by CPZ. At the same exposure time, the activity of SOD reduced first, and increased then, whereas the activity of CAT enhanced first and decreased then. At the same exposure levels of CPZ, the activity of SOD and CAT changed similarly, decreased first, then increased and decreased at last. Within the range of exposure concentrations, the changes in the activity of CAT can more easily reflect the oxidation stress in Carassius auratus by CPZ than those of SOD.
Title: Complete genome of Phenylobacterium zucineum--a novel facultative intracellular bacterium isolated from human erythroleukemia cell line K562 Luo Y, Xu X, Ding Z, Liu Z, Zhang B, Yan Z, Sun J, Hu S, Hu X Ref: BMC Genomics, 9:386, 2008 : PubMed
BACKGROUND: Phenylobacterium zucineum is a recently identified facultative intracellular species isolated from the human leukemia cell line K562. Unlike the known intracellular pathogens, P. zucineum maintains a stable association with its host cell without affecting the growth and morphology of the latter. RESULTS: Here, we report the whole genome sequence of the type strain HLK1T. The genome consists of a circular chromosome (3,996,255 bp) and a circular plasmid (382,976 bp). It encodes 3,861 putative proteins, 42 tRNAs, and a 16S-23S-5S rRNA operon. Comparative genomic analysis revealed that it is phylogenetically closest to Caulobacter crescentus, a model species for cell cycle research. Notably, P. zucineum has a gene that is strikingly similar, both structurally and functionally, to the cell cycle master regulator CtrA of C. crescentus, and most of the genes directly regulated by CtrA in the latter have orthologs in the former. CONCLUSION: This work presents the first complete bacterial genome in the genus Phenylobacterium. Comparative genomic analysis indicated that the CtrA regulon is well conserved between C. crescentus and P. zucineum.
Chlamydomonas reinhardtii is a unicellular green alga whose lineage diverged from land plants over 1 billion years ago. It is a model system for studying chloroplast-based photosynthesis, as well as the structure, assembly, and function of eukaryotic flagella (cilia), which were inherited from the common ancestor of plants and animals, but lost in land plants. We sequenced the approximately 120-megabase nuclear genome of Chlamydomonas and performed comparative phylogenomic analyses, identifying genes encoding uncharacterized proteins that are likely associated with the function and biogenesis of chloroplasts or eukaryotic flagella. Analyses of the Chlamydomonas genome advance our understanding of the ancestral eukaryotic cell, reveal previously unknown genes associated with photosynthetic and flagellar functions, and establish links between ciliopathy and the composition and function of flagella.
Title: [Action of VX on torpedo acetylcholinesterase] Luo Y, Yang SC, Zhang QK Ref: Acta Pharmacol Sin, 8:13, 1987 : PubMed
