Ren Z

References (20)

Title : The GPIHBP1-LPL complex and its role in plasma triglyceride metabolism: Insights into chylomicronemia - Jiang_2023_Biomed.Pharmacother_169_115874
Author(s) : Jiang S , Ren Z , Yang Y , Liu Q , Zhou S , Xiao Y
Ref : Biomed Pharmacother , 169 :115874 , 2023
Abstract : GPIHBP1 is a protein found in the endothelial cells of capillaries that is anchored by glycosylphosphatidylinositol and binds to high-density lipoproteins. GPIHBP1 attaches to lipoprotein lipase (LPL), subsequently carrying the enzyme and anchoring it to the capillary lumen. Enabling lipid metabolism is essential for the marginalization of lipoproteins alongside capillaries. Studies underscore the significance of GPIHBP1 in transporting, stabilizing, and aiding in the marginalization of LPL. The intricate interplay between GPIHBP1 and LPL has provided novel insights into chylomicronemia in recent years. Mutations hindering the formation or reducing the efficiency of the GPIHBP1-LPL complex are central to the onset of chylomicronemia. This review delves into the structural nuances of the GPIHBP1-LPL interaction, the consequences of mutations in the complex leading to chylomicronemia, and cutting-edge advancements in chylomicronemia treatment.
ESTHER : Jiang_2023_Biomed.Pharmacother_169_115874
PubMedSearch : Jiang_2023_Biomed.Pharmacother_169_115874
PubMedID: 37951027

Title : A retrospective screening method for carbamate toxicant exposure based on butyrylcholinesterase adducts in human plasma with ultra-high performance liquid chromatography-tandem mass spectrometry - Ren_2023_J.Chromatogr.B.Analyt.Technol.Biomed.Life.Sci_1225_123775
Author(s) : Ren Z , Chen B , Liang D , Liu D , Lei W , Liu S
Ref : Journal of Chromatography B Analyt Technol Biomed Life Sciences , 1225 :123775 , 2023
Abstract : Carbamate pesticides are extensively used in agriculture for their inhibition to acetylcholinesterase and damages to the insects' neural systems. Because of their toxicity, human poisoning incidents caused by carbamate pesticide exposure have occurred from time to time. What's more, some lethally toxic carbamate toxicants known as carbamate nerve agents (CMNAs) have been supplemented in Schedule 1 of the Annex on Chemicals in the Chemical Weapons Convention (CWC) by Organisation of the Prohibition of Chemical Weapons (OPCW) from 2020. And some other carbamates, like physostigmine, have been used in clinical treatment as anticholinergic drugs and their misuse may also cause damages to the body. Similar to organophosphorus toxicants, carbamate toxicants would react with butyrylcholinesterase (BChE) in plasma when entering the human body, resulting in the BChE adducts, based on which the exposure of carbamate toxicants could be detected retrospectively. In this study, methylcarbamyl nonapeptide and dimethylcarbamyl nonapeptide from pepsin digestion of BChE adducts were identified with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) in product ion scan mode. Carbofuran was chosen as the target to establish the detection method of carbamate toxicant exposure based on methylcarbamyl nonapeptide digested from methylcarbamyl BChE. Procainamide-gel affinity purification, pepsin digestion and UHPLC-MS/MS analysis in multiple reaction monitoring (MRM) mode were applied. Under the optimized conditions of sample preparation and UHPLC-MS/MS MRM analysis, the limits of detection (LODs) reached 10.0 ng/mL of plasma exposed to carbofuran with satisfactory specificity. The quantitation approach was established with d(3)-carbofuran-exposed plasma as the internal standard (IS) and the linearity range was 30.0-1.00 x 10(3) nmol/L (R(2) >0.998) with the accuracy of 95.6%-107% and precision of >=9% relative standard deviation (RSD). The applicability was also evaluated by N,N-dimethyl-carbamates with the LODs of 30.0 nmol/L for pirimicarb-exposed plasma based on dimethylcarbamyl nonapeptide. Because most of carbamate toxicants has methylcarbamyl or dimethylcarbamyl groups, this approach could be applied on the retrospective screening of carbamate toxicant exposure including CMNAs, carbamate pesticides or carbamate drugs. This study could provide an effective means in the fields of CWC verification, toxicological mechanism investigation and down-selection of potential treatment options.
ESTHER : Ren_2023_J.Chromatogr.B.Analyt.Technol.Biomed.Life.Sci_1225_123775
PubMedSearch : Ren_2023_J.Chromatogr.B.Analyt.Technol.Biomed.Life.Sci_1225_123775
PubMedID: 37285767

Title : Detoxification Gene Families at the Genome-Wide Level of Rhus Gall Aphid Schlechtendalia chinensis - He_2022_Genes.(Basel)_13_
Author(s) : He H , Crabbe MJC , Ren Z
Ref : Genes (Basel) , 13 : , 2022
Abstract : The Rhus gall aphid Schlechtendalia chinensis uses the species Rhus chinensis as its primary host plant, on which galls are produced. The galls have medicinal properties and can be used in various situations due to their high tannin content. Detoxification enzymes play significant roles in the insect lifecycle. In this study, we focused on five detoxification gene families, i.e., glutathione-S-transferase (GST), ABC transporter (ABC), Carboxylesterase (CCE), cyto-chrome P450 (CYP), and UDP-glycosyltransferase (UDP), and manually annotated 144 detoxification genes of S. chinensis using genome-wide techniques. The detoxification genes appeared mostly on chromosome 1, where a total of two pair genes were identified to show tandem duplications. There were 38 gene pairs between genomes of S. chinensis and Acyrthosiphon pisum in the detoxification gene families by collinear comparison. Ka/Ks ratios showed that detoxification genes of S. chinensis were mainly affected by purification selection during evolution. The gene expression numbers of P450s and ABCs by transcriptome sequencing data were greater, while gene expression of CCEs was the highest, suggesting they might be important in the detoxification process. Our study has firstly identified the genes of the different detoxification gene families in the S. chinensis genome, and then analyzed their general features and expression, demonstrating the importance of the detoxification genes in the aphid and providing new information for further research.
ESTHER : He_2022_Genes.(Basel)_13_
PubMedSearch : He_2022_Genes.(Basel)_13_
PubMedID: 36140795

Title : Prognostic role of NLGN2 and PTGDS in medulloblastoma based on gene expression omnibus - Ren_2022_Am.J.Transl.Res_14_3769
Author(s) : Ren Z , Gao M , Jiang W
Ref : Am J Transl Res , 14 :3769 , 2022
Abstract : BACKGROUND: Medulloblastoma (MB) is the most common intracranial malignant tumour in children, but genes and pathways involved in its pathogenesis are still under investigation. This study was designed to screen and identify biomarkers of MB to provide markers for clinical diagnosis and prognosis assessment. METHODS: The data sets of GSE109401 and GSE42656 were acquired from Gene expression omnibus (GEO). Limma package in R was adopted to identify the differentially expressed genes (DEGs), and the GSE30074 data set was adopted to analyse their prognostic role. Children with MB (n=55) diagnosed in Affiliated Ezhou Central Hospital were enrolled and assigned to the patient group, and healthy children (n=30) who received physical examination in our hospital during the same time period were assigned to the control group. The two groups were compared in serum NLGN2 and PTGDS levels, and all patients were followed up for three years to understand the associations of Neuroligin 2 (NLGN2) and Prostaglandin D2 synthase (PTGDS) with the survival of patients. RESULTS: With Limma, 247 DEGs were screened out. The LASSO-Cox regression analysis revealed that 6 genes were associated with MB prognosis, and the established model revealed a lower survival rate in the high-risk group. According to Cox regression analysis, NLGN2 and PTGDS may be independent prognostic factors of MB. Similar to the data sets, the Real time-quantitative polymerase chain reaction (RT-qPCR) assay revealed lowly-expressed NLGN2 and PTGDS levels in MB patients, and patients with lower expression of them showed a lower 3-year survival rate. CONCLUSION: With low expression in MB cases, NLGN2 and PTGDS have high prognostic value for MB.
ESTHER : Ren_2022_Am.J.Transl.Res_14_3769
PubMedSearch : Ren_2022_Am.J.Transl.Res_14_3769
PubMedID: 35836891

Title : Effect of Selenium on Brain Injury in Chickens with Subacute Arsenic Poisoning - Ren_2021_Biol.Trace.Elem.Res__
Author(s) : Ren Z , Deng H , Wu Q , Jia G , Wen N , Deng Y , Zhu L , Zuo Z , Deng J
Ref : Biol Trace Elem Res , : , 2021
Abstract : The aim of this study was to investigate the effects of different doses of selenium (Se) on oxidative damage and neurotransmitter-related parameters in arsenic (As)-induced broiler brain tissue damage. Two hundred 1-day-old avian broilers were randomly divided into five groups and fed the following diets: control group (As 0.1 mg/kg + Se 0.2 mg/kg), As group (As 3 mg/kg + Se 0.2 mg/kg), low-Se group (As 3 mg/kg + Se 5 mg/kg), medium-Se group (As 3 mg/kg + Se 10 mg/kg), and high-Se group (As 3 mg/kg + Se 15 mg/kg). Glutathione (GSH), glutathione peroxidase (GSH-PX), nitric oxide (NO), nitric oxide synthase (NOS) activity, glutamate (Glu) concentration, glutamine synthetase (GS) activity, acetylcholinesterase (TchE) activity, and the apoptosis rate of brain cells were measured. The results showed that 3 mg/kg dietary As could induce oxidative damage and neurotransmitter disorder of brain tissue, increase the apoptosis rate of brain cells and cause damage to brain tissue, decrease activities of GSH and GSH-PX, decrease the contents of NO, decrease the activities of iNOS and tNOS, increase contents of Glu, and decrease activities of Gs and TchE. Compared with the As group, the Se addition of the low-Se and medium-Se groups protected against As-induced oxidative damage, neurotransmitter disorders, and the apoptosis rate of brain cells, with the addition of 10 mg/kg Se having the best effect. However, 15 mg/kg Se not only did not produce a protective effect against As damage but actually caused similar or severe damage.
ESTHER : Ren_2021_Biol.Trace.Elem.Res__
PubMedSearch : Ren_2021_Biol.Trace.Elem.Res__
PubMedID: 33594525

Title : Biochemical and behavior effects induced by diheptyl phthalate (DHpP) and Diisodecyl phthalate (DIDP) exposed to zebrafish - Poopal_2020_Chemosphere_252_126498
Author(s) : Poopal RK , Zhang J , Zhao R , Ramesh M , Ren Z
Ref : Chemosphere , 252 :126498 , 2020
Abstract : Both Diheptyl-phthalate (DHpP) and Diisodecyl-phthalate (DIDP) were used extensively as plasticizers. Recently, their occurrence in the environmental matrices and human body fluids have been reported. Unfortunately, these phthalate congeners are without basic toxicity profiles. Hence, we studied the toxic effects of both DHpP and DIDP in the median lethal concentration (LC50 96-h) on zebrafish (Danio rerio). We assessed swimming behavior strength and tissues biomarker responses including total antioxidants capacity (TAOC), transaminases, and acetylcholinesterase (AChE) enzyme. Fish exposed to phthalate congeners (Treatment-I and-II) for 15-days showed alterations on fish swimming behavior and circadian rhythm. At the end of the exposure period, both liver and heart tissue transaminases activities were found to be accelerated in DHpP and DIDP treated fish, when compared to control group. TAOC and AChE activities were found to be decreased in brain, gills, intestine, and muscle tissues of phthalate congeners treated fish than the control group. Alterations observed in the studied biomarkers were concentration-based response. Among treatment groups DHpP showed higher effects. Comparative studies on swimming behavior and biochemical activities were reasonable to know the swimming responses are mediated due to external stress or internal stress. More studies on molecular and biomarkers assessments are warranted on toxicity of emerging contaminants.
ESTHER : Poopal_2020_Chemosphere_252_126498
PubMedSearch : Poopal_2020_Chemosphere_252_126498
PubMedID: 32197170

Title : Organophosphorus flame retardant induced hepatotoxicity and brain AChE inhibition on zebrafish (Danio rerio) - Ramesh_2020_Neurotoxicol.Teratol__106919
Author(s) : Ramesh M , Angitha S , Haritha S , Poopal RK , Ren Z , Umamaheswari S
Ref : Neurotoxicology & Teratology , :106919 , 2020
Abstract : Organophosphorus flame retardants (OPFRs) are high production volume (HPV) chemicals. Recent reports reveal that OPFRs are ubiquitous in the environment. Unfortunately, the toxicity profiles for OPFRs on organisms remain limited. Hence, to illustrate the potential toxic effects of OPFRs at environmental relevant concentrations on aquatic biota in the present study, we investigated biochemical, enzymological, antioxidants, and histological (at long-term study) changes of zebrafish tissues under short- (96 h) and long- (21 days) -term triphenyl phosphate (TPhP) exposure. The hepatic glucose production (except short-term TPhP treatment up to 48 h), aspartate transaminase, alanine transaminase, lactate dehydrogenase, reactive oxygen species generation, lipid peroxide, and catalase activities were found to be increased in TPhP exposed groups when compared to control groups (normal and solvent control). The hepatic protein content and sodium dismutase activity were declined in TPhP exposed groups. Likewise, brain tissue acetylcholinesterase activity was declined in TPhP exposed groups. The hepatic glutathione S-transferase activity increased after 24 h under short-term TPhP exposure (96 h), while under long-term exposure period (21 days) the enzyme activity was accelerated when compared to control groups. Long-term TPhP exposure resulted in a series of morphological anomalies in the hepatic tissues of zebrafish. Our study reveals that TPhP can potentially cause antioxidants imbalance, alterations in enzymological and biochemical profiles, and morphological anomalies in hepatic tissues of zebrafish. Moreover, TPhP could cause neurotoxic effects on zebrafish at studied concentrations. Our findings expand the available toxicity profiles for TPhP on aquatic biota and propose that zebrafish are a good indicator, and studied parameters are valid biomarkers in assessing the eco-toxicological effects of OPFRs.
ESTHER : Ramesh_2020_Neurotoxicol.Teratol__106919
PubMedSearch : Ramesh_2020_Neurotoxicol.Teratol__106919
PubMedID: 32853706

Title : Carboxylesterase genes in nitenpyram-resistant brown planthoppers, Nilaparvata lugens - Mao_2020_Insect.Sci__
Author(s) : Mao K , Ren Z , Li W , Cai T , Qin X , Wan H , Jin BR , He S , Li J
Ref : Insect Sci , : , 2020
Abstract : Carboxylesterases (CarEs) represent one of the major detoxification enzyme families involved in insecticide resistance. However, the function of specific CarE genes in insecticide resistance is still unclear in the insect Nilaparvata lugens (Stal), a notorious rice crop pest in Asia. In this study, a total of 29 putative CarE genes in N. lugens were identified, and they were divided into seven clades; further, the beta-esterase clade was significantly expanded. Tissue-specific expression analysis found that seventeen CarE genes were abundantly distributed in the midgut and fat body, while twelve CarE genes were highly expressed in the head. The expression of most CarE genes was significantly induced in response to the challenge of nitenpyram, triflumezopyrim, chlorpyrifos, isoprocarb and etofenprox. Among these, the expression levels of NlCarE2, NlCarE4, NlCarE9, NlCarE17 and NlCarE24 were increased by each insecticide. RT-qPCR and RNAi assays revealed the NlCarE1 gene to be a candidate gene mainly involved in nitenpyram resistance, while simultaneously silencing NlCarE1 and NlCarE19 produced a stronger effect than silencing either one individually, suggesting a cooperative relationship in resistance formation. These findings lay the foundation for further clarification of insecticide resistance mediated by CarE in N. lugens. This article is protected by copyright. All rights reserved.
ESTHER : Mao_2020_Insect.Sci__
PubMedSearch : Mao_2020_Insect.Sci__
PubMedID: 32495409

Title : The influence of temperature on the toxicity of insecticides to Nilaparvata lugens (Stal) - Mao_2019_Pestic.Biochem.Physiol_156_80
Author(s) : Mao K , Jin R , Li W , Ren Z , Qin X , He S , Li J , Wan H
Ref : Pestic Biochem Physiol , 156 :80 , 2019
Abstract : The toxicity of insecticides is associated with a variety of factors including temperature, and global warming is bound to lead to the outbreak of pests; therefore, it is important to study the influence of temperature on insecticide toxicity and pest control. In this study, the influence of temperature on the toxicity of insecticides to Nilaparvata lugens (BPH) was determined. The results showed that the sensitivity of BPH to cycloxaprid (LC50=42.5-0.388mg/L), nitenpyram (LC50=3.49-0.187mg/L), triflumezopyrim (LC50=0.354-0.0533mg/L) and chlorpyrifos (LC50=36.3-7.41mg/L) increased significantly when the temperature changed from 18 degrees C to 36 degrees C. BPH sensitivity to etofenprox (LC50=9.04-54.2mg/L) was also affected by temperature. Additionally, the feeding amount and the activities of three detoxification enzymes [cytochrome P450 (P450), glutathione S-transferase (GST) and carboxylesterase (CarE)] of BPH at different temperatures were also measured. The feeding amounts were positively correlated with temperature increases while the activities of P450 and GST were significantly inhibited. The correlation analysis showed that changes in P450 activity (but not GST activity) were closely related to the sensitivity of BPH to cycloxaprid, nitenpyram, chlorpyrifos, and etofenprox according to the variation in temperatures. This study provides a theoretical basis for the rational use of chemical pesticides under the global warming trend and provides a reference for the integrated management of BPH in the field.
ESTHER : Mao_2019_Pestic.Biochem.Physiol_156_80
PubMedSearch : Mao_2019_Pestic.Biochem.Physiol_156_80
PubMedID: 31027584

Title : Astrocytic alpha7 Nicotinic Receptor Activation Inhibits Amyloid-beta Aggregation by Upregulating Endogenous alphaB-crystallin through the PI3K\/Akt Signaling Pathway - Ren_2019_Curr.Alzheimer.Res_16_39
Author(s) : Ren Z , Yang M , Guan Z , Yu W
Ref : Curr Alzheimer Res , 16 :39 , 2019
Abstract : BACKGROUND: beta-amyloid (Abeta) aggregation plays an important role in the pathogenesis of Alzheimer's disease (AD), and astrocytes can significantly inhibit Abeta aggregation. Astrocytic alpha7 Neuronal Nicotinic Acetylcholine Receptor (nAChR) upregulation detected in the AD brains is closely associated with Abeta deposits. However, the relationships between the astrocytic alpha7 nAChRs and Abeta aggregation remain unclear. METHODS: The Abeta oligomers levels in astrocytic cell lysates and culture medium were measured after treatment with nicotine or co-treatment with a Phosphatidylinositol 3-Kinase (PI3K)-protein kinase B (Akt) inhibitor. The level of alphaB-Crystallin (Cryab) in astrocytes treated with nicotine for different times or co-treated with alpha7 nAChR antagonists as well as co-incubated with a PI3K or mitogen-activated protein kinase kinase 1/2 (MEK1/2) inhibitor was determined by western blotting. RESULTS: In this study, nicotine pre-treatment in primary astrocytes markedly inhibited Abeta aggregation and upregulated endogenous astrocytic Cryab, while the nicotine-mediated neuroprotective effect was reversed by pre-treatment with a selective alpha7 nAChR antagonist. Furthermore, this neuroprotection against Abeta aggregation was suppressed by LY294002, a PI3K inhibitor. Pre-treatment with nicotine significantly increased the levels of phosphorylated Akt, an effector of PI3K in astrocytes. CONCLUSION: alpha7 nAChR activation and PI3K/Akt signaling transduction contributed to nicotinemediated neuroprotection against Abeta aggregation by modulating endogenous astrocytic Cryab.
ESTHER : Ren_2019_Curr.Alzheimer.Res_16_39
PubMedSearch : Ren_2019_Curr.Alzheimer.Res_16_39
PubMedID: 30345917

Title : The role of dimer asymmetry and protomer dynamics in enzyme catalysis - Kim_2017_Science_355_
Author(s) : Kim TH , Mehrabi P , Ren Z , Sljoka A , Ing C , Bezginov A , Ye L , Pomes R , Prosser RS , Pai EF
Ref : Science , 355 : , 2017
Abstract : Freeze-trapping x-ray crystallography, nuclear magnetic resonance, and computational techniques reveal the distribution of states and their interconversion rates along the reaction pathway of a bacterial homodimeric enzyme, fluoroacetate dehalogenase (FAcD). The crystal structure of apo-FAcD exhibits asymmetry around the dimer interface and cap domain, priming one protomer for substrate binding. This asymmetry is dynamically averaged through conformational exchange on a millisecond time scale. During catalysis, the protomer conformational exchange rate becomes enhanced, the empty protomer exhibits increased local disorder, and water egresses. Computational studies identify allosteric pathways between protomers. Water release and enhanced dynamics associated with catalysis compensate for entropic losses from substrate binding while facilitating sampling of the transition state. The studies provide insights into how substrate-coupled allosteric modulation of structure and dynamics facilitates catalysis in a homodimeric enzyme.
ESTHER : Kim_2017_Science_355_
PubMedSearch : Kim_2017_Science_355_
PubMedID: 28104837
Gene_locus related to this paper: rhopa-q6nam1

Title : The Role of AChE in Swimming Behavior of Daphnia magna: Correlation Analysis of Both Parameters Affected by Deltamethrin and Methomyl Exposure - Ren_2017_J.Toxicol_2017_3265727
Author(s) : Ren Q , Zhao R , Wang C , Li S , Zhang T , Ren Z , Yang M , Pan H , Xu S , Zhu J , Wang X
Ref : J Toxicol , 2017 :3265727 , 2017
Abstract : The unpredictable toxicity of insecticides may cause behavior disorder of biological organisms. In order to assess the role of acetylcholinesterase (AChE) in swimming behavior of Daphnia magna, a correlation analysis of both parameters in 24 h exposure of deltamethrin (DM) and methomyl (MT) was investigated. The behavior responses of D. magna in DM (13.36 mug/L and 33.40 mug/L) and MT (19.66 mug/L and 49.15 mug/L) suggested that recovery behavior in the adjustment phase was crucial, and behavior homeostasis provided them with an optimal way to achieve a wider tolerance against environmental stress. During the experiment, positive effects on AChE activity occurred in the beginning of the exposure. Even though the de novo synthesis of AChE in D. magna might help it recover, the AChE inhibition in different treatments could be observed. Some induction effects on AChE activity at the beginning of exposure occurred, and a 50% decrease may cause toxic effects on behavior. In most treatments, the results showed that both behavior strength and AChE activity stayed in the same field within a correlation circle. These results illustrated that the environmental stress caused by both DM and MT could inhibit AChE activity and subsequently induce a stepwise behavior response, though both pesticides affect it as direct and indirect inhibitors, respectively.
ESTHER : Ren_2017_J.Toxicol_2017_3265727
PubMedSearch : Ren_2017_J.Toxicol_2017_3265727
PubMedID: 29201050
Gene_locus related to this paper: dapul-ACHE1

Title : Does time difference of the acetylcholinesterase (AChE) inhibition in different tissues exist? A case study of zebra fish (Danio rerio) exposed to cadmium chloride and deltamethrin - Zhang_2017_Chemosphere_168_908
Author(s) : Zhang T , Yang M , Pan H , Li S , Ren B , Ren Z , Xing N , Qi L , Ren Q , Xu S , Song J , Ma J
Ref : Chemosphere , 168 :908 , 2017
Abstract : In order to illustrate time difference in toxic effects of cadmium chloride (CdCl2) and deltamethrin (DM), AChE activities were measured in different tissues, liver, muscle, brain, and gill, of Zebra fish (Danio rerio) across different concentrations in this research. The average AChE activity decreased comparing to 0.0 TU with DM (82.81% in 0.1 TU, 56.14% in 1.0 TU and 44.68% in 2.0 TU) and with CdCl2 (74.68% in 0.1 TU, 52.05% in 1.0 TU and 50.14% in 2.0 TU) showed an overall decrease with the increase of exposure concentrations. According to Self-Organizing Map (SOM), the AChE activities were characterized in relation with experimental conditions, showing an inverse relationship with exposure time. As the exposure time was longer, the AChE activities were correspondingly lower. The AChE inhibition showed time delay in sublethal treatments (0.1 TU) in different tissues: the AChE was first inhibited in brain by chemicals followed by gill, muscle and liver (brain > gill > muscle > liver). The AChE activity was almost inhibited synchronously in higher environmental stress (1.0 TU and 2.0 TU). As the AChE inhibition can induce abnormal of behavior movement, these results will be helpful to the mechanism of stepwise behavior responses according to the time difference in different tissues rather than the whole body AChE activity.
ESTHER : Zhang_2017_Chemosphere_168_908
PubMedSearch : Zhang_2017_Chemosphere_168_908
PubMedID: 27825714

Title : Bidirectional Homeostatic Regulation of a Depression-Related Brain State by Gamma-Aminobutyric Acidergic Deficits and Ketamine Treatment - Ren_2016_Biol.Psychiatry_80_457
Author(s) : Ren Z , Pribiag H , Jefferson SJ , Shorey M , Fuchs T , Stellwagen D , Luscher B
Ref : Biological Psychiatry , 80 :457 , 2016
Abstract : BACKGROUND: Major depressive disorder is increasingly recognized to involve functional deficits in both gamma-aminobutyric acid (GABA)ergic and glutamatergic synaptic transmission. To elucidate the relationship between these phenotypes, we used GABAA receptor gamma2 subunit heterozygous (gamma2(+/-)) mice, which we previously characterized as a model animal with construct, face, and predictive validity for major depressive disorder.
METHODS: To assess possible consequences of GABAergic deficits on glutamatergic transmission, we quantitated the cell surface expression of N-methyl-D-aspartate (NMDA)-type and alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)-type glutamate receptors and the function of synapses in the hippocampus and medial prefrontal cortex of gamma2(+/-) mice. We also analyzed the effects of an acute dose of the experimental antidepressant ketamine on all these parameters in gamma2(+/-) versus wild-type mice.
RESULTS: Modest defects in GABAergic synaptic transmission of gamma2(+/-) mice resulted in a strikingly prominent homeostatic-like reduction in the cell surface expression of NMDA-type and AMPA-type glutamate receptors, along with prominent functional impairment of glutamatergic synapses in the hippocampus and medial prefrontal cortex. A single subanesthetic dose of ketamine normalized glutamate receptor expression and synaptic function of gamma2(+/-) mice to wild-type levels for a prolonged period, along with antidepressant-like behavioral consequences selectively in gamma2(+/-) mice. The GABAergic synapses of gamma2(+/-) mice were potentiated by ketamine in parallel but only in the medial prefrontal cortex.
CONCLUSIONS: Depressive-like brain states that are caused by GABAergic deficits involve a homeostatic-like reduction of glutamatergic transmission that is reversible by an acute, subanesthetic dose of ketamine, along with regionally selective potentiation of GABAergic synapses. The data merge the GABAergic and glutamatergic deficit hypotheses of major depressive disorder.
ESTHER : Ren_2016_Biol.Psychiatry_80_457
PubMedSearch : Ren_2016_Biol.Psychiatry_80_457
PubMedID: 27062563

Title : Suppressive subtractive hybridization reveals different gene expression between high and low virulence strains of Cladosporium cladosporioides - Gu_2016_Microb.Pathog_100_276
Author(s) : Gu Y , Liu Y , Cao S , Huang X , Zuo Z , Yu S , Deng J , Ding C , Yuan M , Shen L , Wu R , Wen Y , Ren Z , Zhao Q , Peng G , Zhong Z , Wang C , Ma X
Ref : Microb Pathog , 100 :276 , 2016
Abstract : Cladosporium cladosporioides is a ubiquitous fungus, causing infections in plants, humans, and animals. Suppression subtractive hybridization (SSH) and quantitative real-time PCR (qRT-PCR) were used in this study to identify differences in gene expression between two C. cladosporioides strains, the highly virulent Z20 strain and the lowly virulent Zt strain. A total of 61 unigenes from the forward library and 42 from the reverse library were identified. Gene ontology (GO) analysis showed that these genes were involved in various biological processes, cellular components and molecular functions. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that the unigenes in the forward library corresponded to 5 different pathways and the reverse library unigenes were involved in 3 different pathways. The qRT-PCR results indicated that expressions of APL1, GUD1, CSE1, SPBC3E7.04c and MFS were significantly different between Z20 and Zt strains, while genes encoding the senescence-associated proteins, pse1, nup107, mip1, pex2, icl1 and alpha/beta hydrolase exhibited no significant differences between the two strains. In addition, we found that 5 unigenes encoding mip1, chk1, icl1, alpha/beta hydrolase and beta-glucosidase may be associated with pathogenicity. One unigene (MFS) may be related to the resistance to 14 alpha-demethylase inhibitor fungicides, and 5 unigenes (PEX2, NUP107, PSE1, APL1, and SPBC3E7.04c) may be related to either low spore yield or earlier aging of the Zt strain. Our study may help better understand the molecular mechanism of C. cladosporioides infection, and therefore improve the treatment and prevention of C. cladosporioides induced diseases.
ESTHER : Gu_2016_Microb.Pathog_100_276
PubMedSearch : Gu_2016_Microb.Pathog_100_276
PubMedID: 27744104

Title : The acetylcholinesterase (AChE) inhibition analysis of medaka (Oryzias latipes) in the exposure of three insecticides - Zhu_2015_Pak.J.Pharm.Sci_28_671
Author(s) : Zhu J , Huan C , Si G , Yang H , Yin L , Ren Q , Ren B , Fu R , Miao M , Ren Z
Ref : Pak J Pharm Sci , 28 :671 , 2015
Abstract : The continuous effects on Acetylcholinesterase (AChE) activity of medaka (Oryzias latipes) caused by dichlorvos, methomyl and deltamethrin in vivo were investigated, and the trends of AChE activity inhibition due to the influence of these insecticides were discussed. The LC50-24h of dichlorvos, methomyl and deltamethrin on medaka were 2.3 mg/L, 0.2 mg/L, and 2.9x10(-3) mg/L respectively. The result suggested that at the beginning of the exposure, the AChE activity might increase, and the AChE activity in dead individuals was obviously lower than the live individuals. Though the de novo synthesis of AChE in medaka might help the AChE activity recover, the trends during the exposure in different treatments were downward, and it showed both exposure time and concentration dependent. Meanwhile, higher temperature might cause the AChE inhibition earlier due to the higher metabolic rate. Therefore, as a specific biomarker for organophosphate, carbamate pesticides and pyrethroids, the degree of the AChE inhibition with in vivo conditions is a good tool in continuous monitoring of insecticides, which may induce the nerve conduction disorders.
ESTHER : Zhu_2015_Pak.J.Pharm.Sci_28_671
PubMedSearch : Zhu_2015_Pak.J.Pharm.Sci_28_671
PubMedID: 25796143

Title : Interrogation of the Substrate Profile and Catalytic Properties of the Phosphotriesterase from Sphingobium sp. Strain TCM1: An Enzyme Capable of Hydrolyzing Organophosphate Flame Retardants and Plasticizers - Xiang_2015_Biochemistry_54_7539
Author(s) : Xiang DF , Bigley AN , Ren Z , Xue H , Hull KG , Romo D , Raushel FM
Ref : Biochemistry , 54 :7539 , 2015
Abstract : The most familiar organophosphorus compounds are the neurotoxic insecticides and nerve agents. A related group of organophosphorus compounds, the phosphotriester plasticizers and flame retardants, has recently become widely used. Unlike the neurotoxic phosphotriesters, the plasticizers and flame retardants lack an easily hydrolyzable bond. While the hydrolysis of the neurotoxic organophosphates by phosphotriesterase enzymes is well-known, the lack of a labile bond in the flame retardants and plasticizers renders them inert to typical phosphotriesterases. A phosphotriesterase from Sphingobium sp. strain TCM1 (Sb-PTE) has recently been reported to catalyze the hydrolysis of organophosphorus flame retardants. This enzyme has now been expressed in Escherichia coli, and the activity with a wide variety of organophosphorus substrates has been characterized and compared to the activity of the well-known phosphotriesterase from Pseudomonas diminuta (Pd-PTE). Structure prediction suggests that Sb-PTE has a beta-propeller fold, and homology modeling has identified a potential mononuclear manganese binding site. Sb-PTE exhibits catalytic activity against typical phosphotriesterase substrates such as paraoxon, but unlike Pd-PTE, Sb-PTE is also able to effectively hydrolyze flame retardants, plasticizers, and industrial solvents. Sb-PTE can hydrolyze both phosphorus-oxygen bonds and phosphorus-sulfur bonds, but not phosphorus-nitrogen bonds. The best substrate for Sb-PTE is the flame retardant triphenyl phosphate with a kcat/Km of 1.7 x 10(6) M(-1) s(-1). Quite remarkably, Sb-PTE is also able to hydrolyze phosphotriesters with simple alcohol leaving groups such as tributyl phosphate (kcat/Km = 40 M(-1) s(-1)), suggesting that this enzyme could be useful for the bioremediation of a wide variety of organophosphorus compounds.
ESTHER : Xiang_2015_Biochemistry_54_7539
PubMedSearch : Xiang_2015_Biochemistry_54_7539
PubMedID: 26629649

Title : Lipase immobilized catalytically active membrane for synthesis of lauryl stearate in a pervaporation membrane reactor - Zhang_2014_Bioresour.Technol_172C_16
Author(s) : Zhang W , Qing W , Ren Z , Li W , Chen J
Ref : Bioresour Technol , 172C :16 , 2014
Abstract : A composite catalytically active membrane immobilized with Candida rugosa lipase has been prepared by immersion phase inversion technique for enzymatic synthesis of lauryl stearate in a pervaporation membrane reactor. SEM images showed that a "sandwich-like" membrane structure with a porous lipase-PVA catalytic layer uniformly coated on a polyvinyl alcohol (PVA)/polyethersulfone (PES) bilayer was obtained. Optimum conditions for lipase immobilization in the catalytic layer were determined. The membrane was proved to exhibit superior thermal stability, pH stability and reusability than free lipase under similar conditions. In the case of pervaporation coupled synthesis of lauryl stearate, benefited from in-situ water removal by the membrane, a conversion enhancement of approximately 40% was achieved in comparison to the equilibrium conversion obtained in batch reactors. In addition to conversion enhancement, it was also found that excess water removal by the catalytically active membrane appears to improve activity of the lipase immobilized.
ESTHER : Zhang_2014_Bioresour.Technol_172C_16
PubMedSearch : Zhang_2014_Bioresour.Technol_172C_16
PubMedID: 25218626

Title : AChE inhibition: One dominant factor for swimming behavior changes of Daphnia magna under DDVP exposure - Ren_2014_Chemosphere_120C_252
Author(s) : Ren Z , Zhang X , Wang X , Qi P , Zhang B , Zeng Y , Fu R , Miao M
Ref : Chemosphere , 120C :252 , 2014
Abstract : As a key enzyme that hydrolyzes the neurotransmitter acetylcholine in cholinergic synapses of both vertebrates and invertebrates, acetylcholinesterase (AChE) is strongly inhibited by organophosphates. AChE inhibition may induce the decrease of swimming ability. According to previous research, swimming behavior of different aquatic organisms could be affected by different chemicals, and there is a shortage of research on direct correlation analysis between swimming behavior and biochemical indicators. Therefore, swimming behavior and whole-body AChE activity of Daphnia magna under dichlorvos (DDVP) exposure were identified in order to clarify the relationship between behavioral responses and AChE inhibition in this study. In the beginning, AChE activity was similar in all treatments with the control. During all exposures, the tendency of AChE activity inhibition was the same as the behavioral responses of D. magna. The AChE activity of individuals without movement would decrease to about zero in several minutes. The correlation analysis between swimming behavior of D. magna and AChE activity showed that the stepwise behavioral response was mainly decided by AChE activity. All of these results suggested that the toxicity characteristics of DDVP as an inhibitor of AChE on the swimming behavior of organisms were the same, and the AChE activity inhibition could induce loss of the nerve conduction ability, causing hyperactivity, loss of coordination, convulsions, paralysis and other kinds of behavioral changes, which was illustrated by the stepwise behavioral responses under different environmental stresses.
ESTHER : Ren_2014_Chemosphere_120C_252
PubMedSearch : Ren_2014_Chemosphere_120C_252
PubMedID: 25112705
Gene_locus related to this paper: dapul-ACHE1

Title : Static laue diffraction studies on acetylcholinesterase - Ravelli_1998_Acta.Crystallogr.D.Biol.Crystallogr_54_1359
Author(s) : Ravelli RB , Raves ML , Ren Z , Bourgeois D , Roth M , Kroon J , Silman I , Sussman JL
Ref : Acta Crystallographica D Biol Crystallogr , 54 :1359 , 1998
Abstract : Acetylcholinesterase (AChE) is one of nature's fastest enzymes, despite the fact that its three-dimensional structure reveals its active site to be deeply sequestered within the molecule. This raises questions with respect to traffic of substrate to, and products from, the active site, which may be investigated by time-resolved crystallography. In order to address one aspect of the feasibility of performing time-resolved studies on AChE, a data set has been collected using the Laue technique on a trigonal crystal of Torpedo californica AChE soaked with the reversible inhibitor edrophonium, using a total X-ray exposure time of 24 ms. Electron-density maps obtained from the Laue data, which are of surprisingly good quality compared with similar maps from monochromatic data, show essentially the same features. They clearly reveal the bound ligand, as well as a structural change in the conformation of the active-site Ser200 induced upon binding.
ESTHER : Ravelli_1998_Acta.Crystallogr.D.Biol.Crystallogr_54_1359
PubMedSearch : Ravelli_1998_Acta.Crystallogr.D.Biol.Crystallogr_54_1359
PubMedID: 10089512
Gene_locus related to this paper: torca-ACHE