XENOBIOTICA
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2021
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IF 1.908
Xiaojiao Zheng,Xu Wang,Zifang Ding,Wei Li,Ying Peng,Jiang Zheng
Deferiprone (DFP) is a metal chelating agent generally used to treat patients with thalassaemia, due to iron overload in clinical settings.Studies have revealed that long-term use of DFP can induce hepatotoxicity, however, mechanisms of its toxic action remain unclear. The present studies are aimed to characterize the reactive metabolite of DFP, to define the metabolic pathway, and to determine the P450 enzymes participating in the bioactivation.A demethylation metabolite (M1) was observed in rat liver microsomal incubations. Additionally, a glutathione (GSH) conjugate (M2) and an N-acetylcysteine (NAC) conjugate (M3) were detected in microsomal incubations fortified with DFP and GSH/NAC.Biliary M2 and urinary M3 were respectively found in animals administered DFP.CYP2A6 enzyme dominated the catalysis to bioactivate DFP.
研究领域:
药理学
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毒理学
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临床医学
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DOI
PubMed
高影响因子
CNS Neuroscience & Therapeutics
·
2025
·Vol. 31
·期 7
·e70502
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IF 5
Xin Shu,Xinxin Zou,Jingxuan Zhang,Xu Fang,Xinyu Wang,Hui Wu,Xuan He,Dujuan Sha
Background Neuroinflammation is an important factor in ischemic stroke. Dehydrocostus lactone (DHC) plays an anti-inflammatory role in certain diseases. However, the role of DHC in neuroinflammation after ischemic stroke remains unclear. Methods DHC was administered to lipopolysaccharide (LPS)-treated BV2 cells and a middle cerebral artery occlusion (MCAO) model to detect the levels of inflammatory factors using quantitative real-time PCR, western blotting, and behavioral tests. Morphological changes in microglia were observed using immunofluorescence. The Swiss Target Prediction database was used to predict the target of DHC. Finally, a specific inhibitor of the target protein was used to investigate its potential synergistic role in neuroinflammation, both with and without being combined with DHC. Results The expression of inflammation-related factors both in vivo and in vitro was improved by DHC, and the neurological deficits in mice after MCAO were improved in the DHC administration group. In addition, the Swiss Target Prediction showed that CYP2A6 was a target of DHC. Specifically, the combination of DHC with the CYP2A6 inhibitor showed that DHC exerts anti-inflammatory effects in a CYP2A6-dependent manner. Conclusion Mechanistically, DHC inhibited neuroinflammation by binding to the target CYP2A6. Our study suggests that DHC is a promising new strategy for treating ischemic stroke.
研究领域:
神经生物学
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药理学
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免疫学
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生物化学
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DOI
PubMed
高影响因子
Oncology Letters
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2016
·Vol. 12
·期 6
·5309-5314
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IF 1.482
Xiao Deng,Qianghong Pu,Erhao Wang,Chao Yu
Human cytochrome P450 (CYP) 2A6 participates in the metabolism of nicotine and precarcinogens, thus the deliberate inhibition of CYP2A6 may reduce cigarette consumption and therefore reduce the risk of developing the types of cancer associated with smoking. The inhibitory effects and mechanisms of celery (Apium graveolens) extract on mouse CYP2A5 and human CYP2A6 activity remain unclear. These effects were investigated in mouse and human liver microsomes using coumarin 7‑hydroxylation in a probe reaction. Celery extract reduced CYP2A5 and CYP2A6 activities in vitro in a dose‑dependent manner. In vivo experiments also showed that celery extract markedly decreased CYP2A5 activity. The inhibition of celery extract on CYP2A5 was time‑ and nicotinamide adenine dinucleotide phosphate (NADPH)‑independent, and was markedly reduced by ultracentrifugation. Additionally, the inhibition of celery extract on CYP2A6 was time and NADPH‑dependent. Levels of inhibition were characterized by a Ki, the measure of the tightness of bonds between the enzyme and its inhibitor, of 266.4 µg/ml for CYP2A5, and a Ki of 1,018 µg/ml and Kinact of 0.3/min for CYP2A6. Kinact is the maximal rate of enzyme inactivation at a saturating concentration of inhibitor. The coumarin derivative 5‑methoxypsoralen present in celery extract did not solely to the inhibition of CYP2A5/6 activity. In conclusion, celery extract inhibited the levels of mouse CYP2A5 and human CYP2A6 activity via different mechanisms: Mixed competitive inhibition for CYP2A5 and mechanism‑based inhibition for CYP2A6.
研究领域:
药理学
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生物化学
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毒理学
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DOI
PubMed
高影响因子
PHARMAZIE
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2012
·Vol. 67
·期 12
·1002-1006
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IF 1.006
Dong Rui-Hua,Fang Zhong-Ze,Zhu Liang-Liang,Ge Guang-Bo,Cao Yun-Feng,Li Xiao-Bao,Hu Cui-Min,Yang Ling,Liu Ze-Yuan
Carvacrol and thymol are phenolic compounds with similar structures isolated from many aromatic plants, and have been demonstrated to exert multiple pharmacological effects. The metabolic and pharmacokinetic behaviour of thymol and carvacrol has received much attention. Carvacrol and
thymol have been demonstrated to undergo phase I metabolism such as hydroxylation reaction. However, drug-metabolizing enzymes involved in this process remain unclear. Given that cytochrome P450 s (CYPs) are involved in most phase I metabolism, the aim of the present study was to investigate
the role of CYPs in the metabolism of thymol and carvacrol. After incubation with human liver microsomes (HLMs) in the presence of NADPH, a new metabolite and two metabolites were detected for thymol and carvacrol, respectively. A combination of chemical inhibition studies and assays with
recombinant CYP isoforms demonstrated that CYP2A6 was the predominant drug-metabolizing enzyme involved in the metabolism of thymol and carvacrol. All these results remind the researchers that special attention should be paid on pharmacokinetic and clinical outcomes when thymol or carvacrol
was co-administrated with other compounds mainly undergoing CYP2A6-mediated metabolism.
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
ACTA PHARMACOLOGICA SINICA
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2024
·
IF 6.9
He Rong-rong,Ma Chuan-rui,He Xin,Dong Yan-xi,Li Hui,Chu Zi-xuan,Yang Xi-he,Wang Jia-qi,Wang Ting,Wang Feng-qing,Du Fei-fei,Rao Ying,Yu Wen-xuan,Gao Xiu-mei,Fan Guan-wei,Cheng Chen,Li Chuan
Translational pharmacological research on traditional medicines lays the foundation for precisely understanding how the medicines function in the body to deliver therapeutic benefits. Borneolum syntheticum (Bingpian) is commonly used in Chinese herbal medicines for coronary heart disease, but its specific cardiovascular impact remains poorly understood. Isoborneol, a constituent of Bingpian, has been found to reduce lipid accumulation in macrophages in vitro, but its oral bioavailability is limited. This investigation aimed to evaluate anti-atherosclerotic effects of Bingpian, based on understanding its first-pass metabolism. Human subjects orally received an herbal medicine containing Bingpian and their plasma samples were analyzed to identify the major circulating compounds of Bingpian, with the metabolism that was also characterized in vitro and in mice. The identified compounds were evaluated for their ability to inhibit macrophage foam-cell formation induced by oxidized low-density lipoprotein. Furthermore, the anti-atherosclerotic effect of repeatedly dosed Bingpian was assessed in ApoE −/− mice fed a high-fat diet. In human subjects, the major circulating compounds of Bingpian were metabolites, rather than their precursor constituents borneol and isoborneol. These constituents were efficiently absorbed in the intestinal tract but underwent significant first-pass metabolism, involving UGT2B7-mediated glucuronidation into borneol-2- O -glucuronide and isoborneol-2- O -glucuronide, respectively, and CYP2A6/2B6/3A-mediated oxidation both into camphor. Despite their poor membrane permeability, hepatic efflux of borneol-2- O -glucuronide and isoborneol-2- O -glucuronide into the systemic circulation was enhanced by MRP3/4. The circulating metabolites, particularly their combinations, markedly inhibited macrophage foam-cell formation induced by oxidized low-density lipoprotein in vitro. Sub-chronic administration of Bingpian (30 mg·kg −1 ·d − 1 , i.g.) for 12 weeks significantly decreased atherosclerotic lesion size and enhanced plaque stability in ApoE −/− mice. Systemic exposure to Bingpian metabolites in mice closely resembles that in humans, suggesting that the pharmacodynamic effects of Bingpian in mice are likely applicable to humans. Overall, the cardiovascular benefits of Bingpian involve reducing atherosclerosis by inhibiting foam-cell formation through its metabolites. This investigation supports that oral Bingpian could be a druggable agent for reducing atherosclerosis.
研究领域:
药理学
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心血管疾病
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传统中药
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代谢
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转化研究
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DOI
PubMed
高影响因子
CHEMICO-BIOLOGICAL INTERACTIONS
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2023
·
IF 5.1
He Liu,Zixia Hu,Ningning Han,Yi Yang,Guode Zhao,Mengdie Su,Yue Zhang,Weiwei Li,Ying Peng,Jiang Zheng
Metaxalone (MTX) is a central nervous system (CNS) depressant used for the treatment of acute skeletal muscle pain . Several cases of fatal overdose deaths in the clinical use of MTX, along with the presence of ischemic hepatitis in deceased patients, have been documented. The present study aimed to investigate the metabolic activation of MTX and to define the possible correlation between the metabolic activation and cytotoxicity of MTX. An oxidative metabolite (M1) and a GSH conjugate (M2) were observed in S9 fraction incubations as well as in rat primary hepatocyte culture after exposure to MTX. M1 and M2 were also observed in bile of MTX-treated rats. CYP2A6 was found to dominate the oxidation of MTX. Both methoxsalen (MTS, a CYP2A6 inhibitor) and 2,6-dichloro-4-nitrophenol (DCNP, a sulfotransferase inhibitor) dramatically decreased the formation of M2. Pre-treatment of primary hepatocytes with DCNP or MTS significantly decreased the susceptibility to the cytotoxicity of MTX.
研究领域:
药理学
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毒理学
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药物代谢
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DOI
PubMed
高影响因子
XENOBIOTICA
·
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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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）