Jin T

References (8)

Title : Immobilization of Candida antarctica lipase B on ILs modified CNTs with different chain lengths: Regulation of substrate tunnel Leucine gating - Lu_2023_Int.J.Biol.Macromol_248_125894
Author(s) : Lu Z , Chen M , Jin T , Nian B , Hu Y
Ref : Int J Biol Macromol , 248 :125894 , 2023
Abstract : Ionic liquids (ILs) have been widely used as chemical modifiers to modify the carriers and thus improve the efficiency, activity and stability of the enzymes. However, as thousands of ILs have been found up to date, it's a huge work for screening and designing suitable ILs for immobilization of enzymes. Moreover, the mechanism of improving enzymes catalytic performance is still remain ambiguous. Thus, this study investigated the impact of ILs with different chain lengths on the enzymatic properties of Candida antarctica lipase B (CALB). Molecular dynamics simulations were employed to examine the interaction between ILs modified CNTs and CALB, as well as their effects on CALB's structure. The results revealed that ILs with different chain lengths significantly influenced the absorption orientation of CALB. Tunnel analysis identified a key role for Leu278 in regulating the open or closed state of Tunnel 2 during CALB's catalytic cycle. The weak interaction analysis demonstrated that ILs with suitable chain lengths provided spatial freedom and formed strong interactions with CNTs and ILs (vdW and hbond). This led to a conformational flip of Leu278, stabilizing the open state of Tunnel 2 and improving the activity and stability of immobilized CALB. This study provides novel insights into the design of new green modifiers to modulate carrier performance and obtain immobilized enzymes with better performance, and establishes a theoretical basis for the design and selection of modifiers for ILs in future work.
ESTHER : Lu_2023_Int.J.Biol.Macromol_248_125894
PubMedSearch : Lu_2023_Int.J.Biol.Macromol_248_125894
PubMedID: 37479200

Title : Combined use of GABA and sitagliptin promotes human beta-cell proliferation and reduces apoptosis - Liu_2021_J.Endocrinol_248_133
Author(s) : Liu W , Lau HK , Son DO , Jin T , Yang Y , Zhang Z , Li Y , Prud'homme GJ , Wang Q
Ref : J Endocrinol , 248 :133 , 2021
Abstract : gamma-Aminobutyric acid (GABA) and glucagon-like peptide-1 receptor agonist (GLP-1RA) improve rodent beta-cell survival and function. In human beta-cells, GABA exerts stimulatory effects on proliferation and anti-apoptotic effects, whereas GLP-1RA drugs have only limited effects on proliferation. We previously demonstrated that GABA and sitagliptin (Sita), a dipeptidyl peptidase-4 inhibitor which increases endogenous GLP-1 levels, mediated a synergistic beta-cell protective effect in mice islets. However, it remains unclear whether this combination has similar effects on human beta-cell. To address this question, we transplanted a suboptimal mass of human islets into immunodeficient NOD-scid-gamma mice with streptozotocin-induced diabetes, and then treated them with GABA, Sita, or both. The oral administration of either GABA or Sita ameliorated blood glucose levels, increased transplanted human beta-cell counts and plasma human insulin levels. Importantly, the combined administration of the drugs generated significantly superior results in all these responses, as compared to the monotherapy with either one of them. The proliferation and/or regeneration, improved by the combination, were demonstrated by increased Ki67+, PDX-1+, or Nkx6.1+ beta-cell numbers. Protection against apoptosis was also significantly improved by the drug combination. The expression level of alpha-Klotho, a protein with protective and stimulatory effects on beta cells, was also augmented. Our study indicates that combined use of GABA and Sita produced greater therapeutic benefits, which are likely due to an enhancement of beta-cell proliferation and a decrease in apoptosis.
ESTHER : Liu_2021_J.Endocrinol_248_133
PubMedSearch : Liu_2021_J.Endocrinol_248_133
PubMedID: 33258801

Title : Characterization and crystal structure of prolyl endopeptidase from abalone (Haliotis discus hannai) - Li_2020_Food.Chem_333_127452
Author(s) : Li WY , Li Y , Chen YL , Hu JJ , Mengist HM , Liu GM , Jin T , Cao MJ
Ref : Food Chem , 333 :127452 , 2020
Abstract : Aimed to study the characteristics of prolyl endopeptidase (PEP, EC and its possible role in the degradation of collagen, we cloned the full-length cDNA sequence of PEP from abalone (Haliotis discus hannai) (Hdh-PEP). Recombinant Hdh-PEP (rHdh-PEP) was expressed in vitro, its enzymatic properties were detected, and its secondary structure was analyzed by Circular Dichroism (CD). We for the first time determined the 1.5 crystal structure of rHdh-PEP. The decomposition effect of rHdh-PEP on collagen peptides was analyzed. Our data revealed that the molecular weight of rHdh-PEP is 85 kDa, consisting of a catalytic domain and a beta-propeller domain. The optimal pH and temperature of rHdh-PEP were pH 6.0 and 20 degC, respectively. Using small collagen peptides as substrates, HPLC-ESI-MS analysis confirmed that rHdh-PEP specifically cleaved at the carboxyl side of proline residues, suggesting its role in the degradation of collagen peptides during autolysis.
ESTHER : Li_2020_Food.Chem_333_127452
PubMedSearch : Li_2020_Food.Chem_333_127452
PubMedID: 32673951
Gene_locus related to this paper: haldh-a0a1x9t5x9

Title : Sepsis decreases the activity of acetylcholinesterase by reducing its expression at the neuromuscular junction - Wu_2017_Mol.Med.Rep_16_5263
Author(s) : Wu J , Jin T , Wang H , Li ST
Ref : Mol Med Rep , 16 :5263 , 2017
Abstract : Our previous study demonstrated that sepsis may decrease the activity of acetylcholinesterase (AChE) at the neuromuscular junction (NMJ) of the diaphragm at 24 h, and thus improve the antagonistic action of neostigmine on rocuronium. The present study aimed to determine the effects of sepsis on AChE activity over 2 weeks, which is a more clinically relevant time period. Furthermore, the present study aimed to elucidate the association between AChE activity and its expression at the NMJ during sepsis. Male adult SpragueDawley rats were randomly divided into the sham or sepsis groups. Sepsis was induced by cecal ligation and puncture. On days 1, 3, 7 and 14 after surgery, AChE activity at the NMJ of the diaphragm was detected using a modified Karnovsky and Roots method. Furthermore, AChE expression levels at the NMJ, and in the whole muscle fibers of the diaphragm, were detected by immunohistofluorescence staining and western blot analysis, respectively. AChE activity was significantly decreased in the sepsis group, with its lowest level detected on day 7; however, its activity had partially recovered on day 14 (P<0.01). AChE activity was positively correlated (r=0.975, P=0.025) with its expression at the NMJ, which showed a similar trend over 2 weeks of sepsis. The protein expression levels of AChE in the whole muscle fibers of the diaphragm were significantly decreased on days 1, 3 and 7 in the sepsis group (P<0.01), with the lowest level observed on day 3. In conclusion, sepsis decreased AChE activity by reducing its expression at the NMJ over 14 days; the reduced expression of AChE at the NMJ might be as a result of its reduced muscular production.
ESTHER : Wu_2017_Mol.Med.Rep_16_5263
PubMedSearch : Wu_2017_Mol.Med.Rep_16_5263
PubMedID: 28849127

Title : Combined Oral Administration of GABA and DPP-4 Inhibitor Prevents Beta Cell Damage and Promotes Beta Cell Regeneration in Mice - Liu_2017_Front.Pharmacol_8_362
Author(s) : Liu W , Son DO , Lau HK , Zhou Y , Prud'homme GJ , Jin T , Wang Q
Ref : Front Pharmacol , 8 :362 , 2017
Abstract : gamma-aminobutyric acid (GABA) or glucagon-like peptide-1 based drugs, such as sitagliptin (a dipeptidyl peptidase-4 inhibitor), were shown to induce beta cell regenerative effects in various diabetic mouse models. We propose that their combined administration can bring forth an additive therapeutic effect. We tested this hypothesis in a multiple low-dose streptozotocin (STZ)-induced beta cell injury mouse model (MDSD). Male C57BL/6J mice were assigned randomly into four groups: non-treatment diabetic control, GABA, sitagliptin, or GABA plus sitagliptin. Oral drug administration was initiated 1 week before STZ injection and maintained for 6 weeks. GABA or sitagliptin administration decreased ambient blood glucose levels and improved the glucose excursion rate. This was associated with elevated plasma insulin and reduced plasma glucagon levels. Importantly, combined use of GABA and sitagliptin significantly enhanced these effects as compared with each of the monotherapies. An additive effect on reducing water consumption was also observed. Immunohistochemical analyses revealed that combined GABA and sitagliptin therapy was superior in increasing beta cell mass, associated with increased small-size islet numbers, Ki67+ and PDX-1+ beta cell counts; and reduced Tunel+ beta cell counts. Thus, beta cell proliferation was increased, whereas apoptosis was reduced. We also noticed a suppressive effect of GABA or sitagliptin on alpha cell mass, which was not significantly altered by combining the two agents. Although either GABA or sitagliptin administration delays the onset of MDSD, our study indicates that combined use of them produces superior therapeutic outcomes. This is likely due to an amelioration of beta cell proliferation and a decrease of beta cell apoptosis.
ESTHER : Liu_2017_Front.Pharmacol_8_362
PubMedSearch : Liu_2017_Front.Pharmacol_8_362
PubMedID: 28676760

Title : Sepsis Strengthens Antagonistic Actions of Neostigmine on Rocuronium in a Rat Model of Cecal Ligation and Puncture - Wu_2016_Chin.Med.J.(Engl)_129_1477
Author(s) : Wu J , Jin T , Wang H , Li ST
Ref : Chinese Medical Journal (Engl) , 129 :1477 , 2016
Abstract : BACKGROUND: The antagonistic actions of anticholinesterase drugs on non-depolarizing muscle relaxants are theoretically related to the activity of acetylcholinesterase (AChE) in the neuromuscular junction (NMJ). However, till date the changes of AChE activity in the NMJ during sepsis have not been directly investigated. We aimed to investigate the effects of sepsis on the antagonistic actions of neostigmine on rocuronium (Roc) and the underlying changes of AChE activity in the NMJ in a rat model of cecal ligation and puncture (CLP).
METHODS: A total of 28 male adult Sprague-Dawley rats were randomized to undergo a sham surgery (the sham group, n = 12) or CLP (the septic group, n = 16). After 24 h, the time-response curves of the antagonistic actions of 0.1 or 0.5 mumol/L of neostigmine on Roc (10 mumol/L)-depressed diaphragm twitch tension were measured. Meanwhile, the activity of AChE in the NMJ was detected using a modified Karnovsky and Roots method. The mRNA levels of the primary transcript and the type T transcript of AChE (AChET) in the diaphragm were determined by real-time reverse transcription-polymerase chain reaction.
RESULTS: Four of 16 rats in the septic group died within 24 h. The time-response curves of both two concentrations of neostigmine in the septic group showed significant upward shifts from those in the sham group (P < 0.001 for 0.1 mumol/L; P = 0.009 for 0.5 mumol/L). Meanwhile, the average optical density of AChE in the NMJ in the septic group was significantly lower than that in the sham group (0.517 +/- 0.045 vs. 1.047 +/- 0.087, P < 0.001). The AChE and AChETmRNA expression levels in the septic group were significantly lower than those in the sham group (P = 0.002 for AChE; P = 0.001 for AChET).
CONCLUSIONS: Sepsis strengthened the antagonistic actions of neostigmine on Roc-depressed twitch tension of the diaphragm by inhibiting the activity of AChE in the NMJ. The reduced content of AChE might be one of the possible causes of the decreased AChE activity in the NMJ.
ESTHER : Wu_2016_Chin.Med.J.(Engl)_129_1477
PubMedSearch : Wu_2016_Chin.Med.J.(Engl)_129_1477
PubMedID: 27270546

Title : Identification of resistance-responsive proteins in larvae of Bactrocera dorsalis (Hendel), for pyrethroid toxicity by a proteomic approach - Jin_2010_Pestic.Biochem.Physiol_96_1
Author(s) : Jin T , Zeng L , Lu Y , Xu Y , Liang G
Ref : Pesticide Biochemistry and Physiology , 96 :1 , 2010
Abstract : Insect resistance to the pyrethroid toxins has been examined previously using a number of traditional biochemical and molecular techniques. In this study, a proteomic approach involving two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) and tandem mass spectrometry (MS/MS) were applied to examine changes in resistant stains larvae of Bactracera dorsalis Hendel induced by pyrethroid treatment over a 3 h, 6 h and 12 h time period, and a number of proteins changes were observed to change in the level of regulation. Out of total 15 proteins, 9 proteins were observed only after pyrethroid treatment; 6 proteins showed different expression. After MALDI-TOF analyses and peptide mapping method, the data was compared with those of the known proteins available in public databases. Sequence analyses revealed that resistance response correlates with up-regulation (glycerol-3-phosphate dehydrogenase) and down-regulation (ATP-ADP antiporter) of energy-related proteins. It indicated that increased metabolism and energy-indeed as a resistance response to pyrethroid toxins. The regulation of cytoskeleton proteins were possibly a B. dorsalis tissue repair response or in cell division. Up-regulation of protein synthesis would results in substantial bioenergetic enhancement, suggesting a trade-off insect resistance to pyrethroid. Down regulation of neural protein indicated that neural system was physically injured after pyrethroid stress. Some remaining proteins were not identifiable, suggesting these may be novel proteins. Oriental fruit fly proteomes of pesticide induced provide an integrative basis for consolidating our knowledge of insect resistance. The results pave the way for future investigation of the alteration of the insect resistance to chemical pesticides.
ESTHER : Jin_2010_Pestic.Biochem.Physiol_96_1
PubMedSearch : Jin_2010_Pestic.Biochem.Physiol_96_1

Title : [The acute effects of dimethoate on the muscarinic-receptors of rat brains and the relationship between muscarinic-receptors and cholinesterase] - Sun_2002_Zhonghua.Lao.Dong.Wei.Sheng.Zhi.Ye.Bing.Za.Zhi_20_293
Author(s) : Sun Y , Zhou Z , Hu Y , Chen J , Jin T
Ref : Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi , 20 :293 , 2002
Abstract : OBJECTIVE: To study the acute effects of dimethoate on the muscarinic-receptors(M1, M2) in the brain of rats.
METHODS: 24 Sprague-Dawley rats were divided into 4 groups randomly. They were administered subcutaneously with 0, 25, 50, 100 mg/kg dimethoate, respectively. Brains were removed after 48 hours of administration. Radioligand binding assay was used to determine the density and affinity of M1 and M2 receptors.
RESULTS: Rats in the treated group showed low density of M1 and M2 receptors compared with the control rats. The brain M1 receptor density of the rats in the highest dosage group was significantly lower than that in the control group while brain M2 receptors density had a decrease trend with increasing dosage, but the difference showed no significance. However, there were no differences of the affinity of both M1 and M2 among different treated groups. Correlation analysis showed there is positive relationship between cholinesterase activity and density of M1 receptors(r = 0.583, P < 0.01). CONCLUSION: M1 and M2 receptors density decreased with the increasing dosage of dimethoate. It is suggested that the alleviating of cholinergic symptoms may be due to the decrease of M1 and M2 receptors in rat brain.
ESTHER : Sun_2002_Zhonghua.Lao.Dong.Wei.Sheng.Zhi.Ye.Bing.Za.Zhi_20_293
PubMedSearch : Sun_2002_Zhonghua.Lao.Dong.Wei.Sheng.Zhi.Ye.Bing.Za.Zhi_20_293
PubMedID: 14694657