ANALYST
·
2024
·
IF 3.6
Jiahuan Zhang,Chaoqun Fei,Shulan Qi,Jiaqi Fu,Shi Zhou,Zhong Wang,Jinlian Li,Yanli Zhao,Dongmei Wu
The electrochemical detection method of cytotoxicity using intracellular purines as biomarkers has shown great potential for in vitro drug toxicity evaluation. However, no electrochemical detection system based on an in vitro drug metabolism mechanism has been devised. In this paper, electrochemical voltammetry was used to investigate the effect of the S9 system on the electrochemical behavior of HepG2 cells, and benzo[a]pyrene, fluoranthene, and pyrene were employed to investigate the sensitivity of electrochemical signals of cells to the cytotoxicity of drugs metabolized by the S9 system. The results showed that, within 8 h of exposure to the S9 system, the electrochemical signal of HepG2 cells at 0.7 V did not alter noticeably. The levels of xanthine, guanine, hypoxanthine, and adenine in the cells were not significantly altered. Compared with the absence of S9 system metabolism, benzo[a]pyrene and fluoranthene processed by the S9 system decreased the electrochemical signal of the cells in a dose-dependent manner, while pyrene did not change it appreciably. HPLC also revealed that benzo[a]pyrene and fluoranthene metabolized by the S9 system decreased the intracellular purine levels, whereas pyrene had no effect on them before and after S9 system metabolism. The cytotoxicity results of the three drugs examined by electrochemical voltammetry and MTT assay showed a strong correlation and good agreement. The S9 system had no effect on the intracellular purine levels or the electrochemical signal of cells. When the drug was metabolized by the S9 system, variations in cytotoxicity could be precisely detected by electrochemical voltammetry.
研究领域:
毒理学
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药理学
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分析化学
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DOI
PubMed
高影响因子
XENOBIOTICA
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2018
·
IF 1.857
Yue Li,Yujuan Fan,Huizong Su,Qian Wang,Guo-Fu Li,Yiyang Hu,Jian Jiang,Bo Tan,Furong Qiu
Tanshinone I (TSI) is a lipophilic diterpene in Salvia miltiorrhiza with versatile pharmacological activities. However, metabolic pathway of TSI in human is unknown.In this study, we determined major metabolites of TSI using a preparation of human liver microsomes (HLMs) by HPLC-UV and Q-Trap mass spectrometer. A total of 6 metabolites were detected, which indicated the presence of hydroxylation, reduction as well as glucuronidation.Selective chemical inhibition and purified cytochrome P450 (CYP450) isoform screening experiments revealed that CYP2A6 was primarily responsible for TSI Phase I metabolism. Part of generated hydroxylated TSI was glucuronidated via several glucuronosyltransferase (UGT) isoforms including UGT1A1, UGT1A3, UGT1A7, UGT1A9, as well as extrahepatic expressed isoforms UGT1A8 and UGT1A10. TSI could be reduced to a relatively unstable hydroquinone intermediate by NAD(P)H: quinone oxidoreductase 1 (NQO1), and then immediately conjugated with glucuronic acid by a panel of UGTs, especially UGT1A9, UGT1A1 and UGT1A8. Additionally, NQO1 could also reduce hydroxylated TSI to a hydroquinone intermediate, which was immediately glucuronidated by UGT1A1.The study demonstrated that hydroxylation, reduction as well as glucuronidation were the major pathways for TSI biotransformation, and six metabolites generated by CYPs, NQO1 and UGTs were found in HLMs and S9 subcellular fractions.
研究领域:
药理学
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代谢
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药物代谢
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PubMed
高影响因子
CHEMICO-BIOLOGICAL INTERACTIONS
·
2023
·
IF 5.1
Xiaoting Luo,Feifei Lu,Zhiyue Yin,Zhiyun Zhou,Zhongmin Wang,Hongjian Zhang
Carboxylesterase 1 (CES1) is a hydrolytic enzyme that plays an important role in the activation or deactivation of many therapeutic agents, thus affecting their pharmacokinetic and pharmacodynamic outcomes. Using rat liver S9 as an enzyme source and enalapril as a CES1 substrate, the present study examined effects of a number of flavonoids on the formation of enalaprilat (the active form of enalapril) produced by CES1-mediated hydrolysis. While a majority of flavonoids tested showed inhibition on CES1, an unexpected hormetic effect was observed for epigallocatechin (EGC) and epigallocatechin gallate (EGCG), i.e., stimulatory effect at low concentrations and enzyme inhibition at high concentrations. Further experiments revealed that oxidative stress caused by hydrogen peroxide, arachidonic acid plus iron, and oxidized low density lipoproteins (oxLOL) reduced CES1 activity in rat liver S9 and the loss of CES1 enzyme activity could be rescued largely by EGC or EGCG. In contrast, such effects were minimal in human liver S9, probably due to the presence of a higher ratio of reduced vs oxidized forms of glutathione . The above findings suggest that the polyphenolic nature of EGC or EGCG might be responsible for rescuing CES1 activity under oxidative stress. Because of the importance of CES1 in drug activation or deactivation and rat liver S9 as a versatile in vitro system used for drug metabolism studies and drug safety assessment , caution should be exercised to avoid potential biases for data interpretation and decision making when CES1 activity in rat liver S9 is evaluated with dependency on experimental conditions.
研究领域:
药理学
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毒理学
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生物化学
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药物代谢
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酶学
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DOI
PubMed
高影响因子
Applied Sciences-Basel
·
2021
·Vol. 11
·期 24
·11661
·
IF 2.679
Yingying Mao,Shaojun Zhou,Mingcheng Xu,Su Zeng,Weimin Fan,Lushan Yu,Nengming Lin
In the face of mounting global antibiotic resistance, which has become a critical clinical problem, antimicrobial peptides (AMPs) have received considerable interest as new therapeutics with the efficacy for the treatment of multidrug-resistant (MDR) infections due to their novel mechanism. However, certain inherent shortcomings such as instability seriously limit their systemic applications in the clinic. In this study, we intend to clarify the connection between three configurations of IK8 and their stability in plasma and liver S9 of various species by confirming the metabolites. The structural information of these metabolites was scanned and identified using HPLC and Q-TOF, respectively. The results found that IK8-D exhibits superior stability, compared with IK8-2D and IK8-L in plasma and liver S9 incubation, which indicated D- type amino acids could significantly increase the stability of antimicrobial peptides.Keywords:antimicrobial peptide;IK8;metabolite;Q-TOF
研究领域:
药理学
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生物化学
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DOI
高影响因子
BIOMEDICAL CHROMATOGRAPHY
·
2026
·Vol. 40
·期 4
·e70415
·
IF 1.7
Yawen Cong,Chongzhuang Tang,Zhiqiang Li,Yang Gao,Lijuan Chen,Haibo Xu,Xingxing Diao
Semaglutide, a glucagon-like peptide-1 receptor agonist, stands as a paradigm of successful peptide drug development. Although absorption, distribution, metabolism and excretion characteristics of semaglutide have been thoroughly studied in both animals and humans, a reliable in vitro screening model for evaluating metabolic behavior of semaglutide and other peptides remains an unmet need in drug development. This study established a novel ultrahigh performance liquid chromatography coupled to high-resolution mass spectrometry method to elucidate the species-specific metabolic pathways of semaglutide. Semaglutide was incubated with liver S9 fractions from human, monkey, dog, rat, and mouse for 1 h, respectively. For the in vivo study, rats were subcutaneously injected with semaglutide (10 mg/kg) for subsequent plasma collection. Data-dependent acquisition was performed to obtain the fragment ions, enabling identification of drug-related materials. Notably, a diagnostic fragment ion at m / z 469, formed from the cleavage of side chain, facilitated metabolite screening. Consequently, a total of 31 metabolites were detected and characterized, constituting a comprehensive metabolic profile of semaglutide in liver S9 fractions and rat plasma. Major metabolic pathways involved hydrolysis of peptide backbone. Our findings provided a robust methodological framework for the screening and metabolism prediction of peptide candidates, supporting the comprehensive safety and efficacy assessment.
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高影响因子
MOLECULAR MEDICINE
·
2022
·Vol. 28
·期 1
·1-15
·
IF 6.376
Wang Bingwu,Gao Jian,Zhao Zhongjun,Zhong Xuefei,Cui Hao,Hou Hui,Zhang Yanping,Zheng Junnian,Di Jiehui,Liu Yong
Background Targeting ribosome biogenesis to activate p53 has recently emerged as a therapeutic strategy in human cancer. Among various ribosomal proteins, RPL11 centralizes the nucleolar stress-sensing pathway by binding MDM2, leading to MDM2 inactivation and p53 activation. Therefore, the identification of MDM2-binding RPL11-mimetics would be valuable for anti-cancer therapeutics.Methods Based on the crystal structure of the interface between RPL11 and MDM2, we have identified 15 potential allosteric modulators of MDM2 through the virtual screening.Results One of these compounds, named S9, directly binds MDM2 and competitively inhibits the interaction between RPL11 and MDM2, leading to p53 stabilization and activation. Moreover, S9 inhibits cancer cell proliferation in vitro and in vivo. Mechanistic study reveals that MDM2 is required for S9-induced G2 cell cycle arrest and apoptosis, whereas p53 contributes to S9-induced apoptosis.Conclusion sPutting together, S9 may serve as a lead compound for the development of an anticancer drug that specifically targets RPL11-MDM2-p53 pathway.
研究领域:
肿瘤学
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药理学
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分子生物学
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DOI
PubMed
高影响因子
MOLECULAR NUTRITION & FOOD RESEARCH
·
2013
·Vol. 57
·期 5
·877-885
·
IF 4.31
Zhong-Jian Chen,Yan-Qing Dai,Si-Si Kong,Fei-Feng Song,Li-Ping Li,Jian-Feng Ye,Ru-Wei Wang,Su Zeng,Hui Zhou,Hui-Di Jiang
Scope The study aimed to investigate the regioselectivity of methylation of luteolin (3′,4′,5,7-tetrahydroxyflavone) in human in vitro and in vivo. Methods and results Recombinant human catechol- O -methyltransferase (COMT) and human liver S9 were utilized to study the kinetics of meta (3′)- and para (4′)- methylation of luteolin, and urine samples from volunteers after giving a luteolin-containing formulation were collected to determine the ratio of para-/meta-production. The results showed luteolin favored a para-methylation, with a ratio of of para-/meta-production in CL int (1.43 in recombinant human COMT and 1.47 in human liver S9), which was contrary to the known substrates of COMT. However, the result of urine sample assay showed a preference of meta-methylation with a ratio of of para-/meta-production (0.460 ± 0.126). To elucidate the mechanism for different preference of methylation of luteolin in vitro and in vivo, metabolism stability of the meta- and para-methylated luteolin was evaluated in human liver microsomes and recombinant human CYP450s, which revealed that para-methylated luteolin was more easily demethylated by human CYP1A2 and CYP3A4/5 than meta-methylated luteolin. Conclusion Luteolin was a rare substrate of human COMT favoring a para-methylation, but further demethylation by human CYP1A2 and CYP3A4/5 caused a preference of accumulation in meta-methylated luteolin in vivo.
研究领域:
药理学
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生物化学
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分子生物学
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DOI
PubMed
高影响因子
FOOD AND CHEMICAL TOXICOLOGY
·
2023
·
IF 4.3
Xin Wang,Guangyun Ran,Yufen Liao,Bowen Gong,Chutian Wu,Rong Tan,Ying Liu,Shiyu Zhang,Ying Peng,Weiwei Li,Jiang Zheng
Safrole (SFL) is an IARC class 2B carcinogen. To better understand the mechanism involved in SFL toxicity, we explored the potential interactions between SFL metabolites and RNA. Three guanosine adducts (G1-G3), two adenosine adducts (A1-A2), and two cytosine adducts (C1–C2) were detected by LC-MS/MS in mouse liver S9 incubations, cultured mouse primary hepatocytes, and liver tissues of mice after exposure to SFL. These adducts were chemically synthesized, and one of the guanosine adducts was structurally characterized by 1 H-NMR. Studies in vitro and in vivo showed that SFL was oxidized by cytochrome P450 enzymes to the corresponding 1′-hydroxyl metabolite which was further metabolized by sulfotransferases to form allylic sulfate esters. The formed reactive intermediate(s) subsequently reacted with bases of RNA, leading to RNA adduction, which could play a partial role in the toxicities of SFL through the alteration of RNA biochemical properties and interruption of RNA functions.
研究领域:
毒理学
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药理学
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分子生物学
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生物化学
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Xinqi Xu,Jinchang Zhong,Bingmei Su,Lian Xu,Xiaokun Hong,Juan Lin
The synthesis of steroids is challenging through multistep steroidal core modifications with high site-selectivity and productivity. In this work, a novel enzymatic cascade system was constructed for synthesis of testolactone by specific C17 lactonization/Δ 1 -dehydrogenation from inexpensive androstenedione using an engineered polycyclic ketone monooxygenase (PockeMO) and an appropriate 3-ketosteroid-Δ 1 -dehydrogenase ( Re KstD). The focused saturation mutagenesis in the substrate binding pocket was implemented for evolution of PockeMO to eliminate the bottleneck effect. A best mutant MU3 (I225L/L226V/L532Y) was obtained with 20-fold higher specific activity compared to PockeMO. The catalytic efficiency ( k cat / K m) of MU3 was 171-fold higher and the substrate scope shifted to polycyclic ketones. Molecular dynamic simulations suggested that the activity was improved by stabilization of the pre-lactonization state and generation of productive orientation of 4-AD mediated by distal L532Y mutation. Based on that, the three genes, MU3, Re KstD and a ketoreductase for NADPH regeneration, were rationally integrated in one cell via expression fine-tuning to form the efficient single cell catalyst E. coli S9. The single whole-cell biocatalytic process was scaled up and could generate 9.0 g/L testolactone with the high space time yield of 1 g/L/h without steroidal by-product, indicating the potential for site-specific and one-pot synthesis of steroid.
研究领域:
生物化学
·
生物技术
·
酶学
·
合成生物学
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药物化学
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产品关联
DOI
PubMed
高影响因子