1
|
Lu J, Shang X, Zhong W, Xu Y, Shi R, Wang X. New insights of CYP1A in endogenous metabolism: a focus on single nucleotide polymorphisms and diseases. Acta Pharm Sin B 2020; 10:91-104. [PMID: 31998606 PMCID: PMC6984740 DOI: 10.1016/j.apsb.2019.11.016] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 10/13/2019] [Accepted: 10/16/2019] [Indexed: 12/31/2022] Open
Abstract
Cytochrome P450 1A (CYP1A), one of the major CYP subfamily in humans, not only metabolizes xenobiotics including clinical drugs and pollutants in the environment, but also mediates the biotransformation of important endogenous substances. In particular, some single nucleotide polymorphisms (SNPs) for CYP1A genes may affect the metabolic ability of endogenous substances, leading to some physiological or pathological changes in humans. This review first summarizes the metabolism of endogenous substances by CYP1A, and then introduces the research progress of CYP1A SNPs, especially the research related to human diseases. Finally, the relationship between SNPs and diseases is discussed. In addition, potential animal models for CYP1A gene editing are summarized. In conclusion, CYP1A plays an important role in maintaining the health in the body.
Collapse
Key Words
- CYP, cytochrome P450
- CYP1A
- EOAs, cis-epoxyoctadecenoics
- Endogenous substances
- FSH, follicle stimulating hormone
- HODEs, hydroxyoctadecdienoic acids
- IQ, 2-amino-3-methylimidazo [4,5-f] quinoline
- KO, knockout
- LIF/STAT3, inhibiting leukemia inhibitory factor/signal transducer and activator of transcription 3
- Metabolism and disease
- PhIP, 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine
- SNPs
- SNPs, single nucleotide polymorphisms
- WT, wild type
- Xenobiotics
- t-RA, all-trans-retinoic acid
- t-ROH, all-trans-retinol
Collapse
Affiliation(s)
- Jian Lu
- Changning Maternity and Infant Health Hospital, East China Normal University, Shanghai 200051, China
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Xuyang Shang
- Changning Maternity and Infant Health Hospital, East China Normal University, Shanghai 200051, China
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Weiguo Zhong
- Changning Maternity and Infant Health Hospital, East China Normal University, Shanghai 200051, China
| | - Yuan Xu
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Rong Shi
- Department of Pharmacology, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Xin Wang
- Changning Maternity and Infant Health Hospital, East China Normal University, Shanghai 200051, China
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| |
Collapse
|
2
|
Piccinato CA, Neme RM, Torres N, Silvério R, Pazzini VB, Rosa E Silva JC, Ferriani RA. Is cytochrome P450 3A4 regulated by menstrual cycle hormones in control endometrium and endometriosis? Mol Cell Biochem 2016; 427:81-89. [PMID: 27995413 DOI: 10.1007/s11010-016-2899-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 12/02/2016] [Indexed: 10/20/2022]
Abstract
The estrogen-metabolizing activities of cytochrome P450 (CYP) enzymes have been implicated in endometriosis. However, their regulation in various sources of endometrial tissue under different hormonal conditions has not been clarified. Our objective was to study the hormone regulation of a specific CYP enzyme, namely CYP3A4, in control (n = 15) and endometriosis patients (n = 42). To this end, we evaluated mRNA expression (using real-time PCR) of CYP3A4 in tissue samples classified according to the phase of menstrual cycle at which they were obtained as confirmed by the related circulating hormone levels. Protein expression was also evaluated by Western Blot. In order to further investigate the hormonal regulation of CYP3A4, stromal cells from ovarian endometriotic lesions were cultured with the prevailing hormones of the distinct phases of the menstrual cycle. We observed that all control and endometriosis tissues express CYP3A4. Nevertheless, changes in CYP3A4 gene expression related to cycle phase were only seen in the control eutopic endometrium and not in samples from endometriosis patients, with an increase in the luteal phase. Stromal cells isolated from ovarian endometriotic lesions expressed CYP3A4 and their exposure to luteal phase-mimicking hormones (estradiol + progesterone) reduced CYP3A4 mRNA in parallel with a diminished expression of the corresponding receptors, estrogen receptor alpha and progesterone receptor. Our findings suggest that steroid hormones are able to regulate CYP3A4 mRNA expression, although the circulating levels of these hormones can only regulate control endometrium and not endometriosis tissues, probably because of dysregulated local steroid concentration in these latter samples.
Collapse
Affiliation(s)
- Carla A Piccinato
- Hospital Israelita Albert Einstein, 627/701, São Paulo, SP, 05652-900, Brazil. .,Department of Gynaecology and Obstetrics, School of Medicine of RibeirãoPreto, Universidade de São Paulo, São Paulo, Brazil.
| | - Rosa M Neme
- Hospital Israelita Albert Einstein, 627/701, São Paulo, SP, 05652-900, Brazil.,Centro de Endometriose São Paulo, Av. República do Líbano, 460, São Paulo, SP, 04502-000, Brazil
| | - Natália Torres
- Hospital Israelita Albert Einstein, 627/701, São Paulo, SP, 05652-900, Brazil
| | - Renata Silvério
- Hospital Israelita Albert Einstein, 627/701, São Paulo, SP, 05652-900, Brazil
| | | | - Júlio C Rosa E Silva
- Department of Gynaecology and Obstetrics, School of Medicine of RibeirãoPreto, Universidade de São Paulo, São Paulo, Brazil
| | - Rui A Ferriani
- Department of Gynaecology and Obstetrics, School of Medicine of RibeirãoPreto, Universidade de São Paulo, São Paulo, Brazil
| |
Collapse
|
3
|
Liu W, Shi J, Zhu L, Dong L, Luo F, Zhao M, Wang Y, Hu M, Lu L, Liu Z. Reductive metabolism of oxymatrine is catalyzed by microsomal CYP3A4. DRUG DESIGN DEVELOPMENT AND THERAPY 2015; 9:5771-83. [PMID: 26586934 PMCID: PMC4636097 DOI: 10.2147/dddt.s92276] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Oxymatrine (OMT) is a pharmacologically active primary quinolizidine alkaloid with various beneficial and toxic effects. It is confirmed that, after oral administration, OMT could be transformed to the more toxic metabolite matrine (MT), and this process may be through the reduction reaction, but the study on the characteristics of this transformation is limited. The aim of this study was to investigate the characteristics of this transformation of OMT in the human liver microsomes (HLMs) and human intestinal microsomes (HIMs) and the cytochrome P450 (CYP) isoforms involved in this transformation. The current studies demonstrated that OMT could be metabolized to MT rapidly in HLMs and HIMs and CYP3A4 greatly contributed to this transformation. All HLMs, HIMs, and CYP3A4 isoform mediated reduction reaction followed typical biphasic kinetic model, and Km, Vmax, and CL were significant higher in HLMs than those in HIMs. Importantly, different oxygen contents could significantly affect the metabolism of OMT, and with the oxygen content decreased, the formation of metabolite was increased, suggesting this transformation was very likely a reduction reaction. Results of this in vitro study elucidated the metabolic pathways and characteristics of metabolism of OMT to MT and would provide a theoretical basis and guidance for the safe application of OMT.
Collapse
Affiliation(s)
- Wenqin Liu
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, People's Republic of China ; International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China
| | - Jian Shi
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, People's Republic of China ; International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China
| | - Lijun Zhu
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China
| | - Lingna Dong
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, People's Republic of China
| | - Feifei Luo
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China
| | - Min Zhao
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China
| | - Ying Wang
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China
| | - Ming Hu
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China ; Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX, USA
| | - Linlin Lu
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China
| | - Zhongqiu Liu
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, People's Republic of China ; International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China
| |
Collapse
|
4
|
Wu L, Zhong W, Liu J, Han W, Zhong S, Wei Q, Liu S, Tang L. Human microsomal cyttrochrome P450-mediated reduction of oxysophocarpine, an active and highly toxic constituent derived from Sophora flavescens species, and its intestinal absorption and metabolism in rat. Fitoterapia 2015; 105:26-36. [PMID: 26045316 DOI: 10.1016/j.fitote.2015.05.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 05/27/2015] [Accepted: 05/28/2015] [Indexed: 10/23/2022]
Abstract
Oxysophocarpine (OSC), an active and toxic quinolizidine alkaloid, is highly valued in Sophora flavescens Ait. and Subprostrate sophora Root. OSC is used to treat inflammation and hepatitis for thousands of years in China. This study aims to investigate the CYP450-mediated reduction responsible for metabolizing OSC and to evaluate the absorption and metabolism of OSC in rat in situ. Four metabolites were identified, with sophocarpine (SC) as the major metabolite. SC formation was rapid in human and rat liver microsomes (HLMs and RLMs, respectively). The reduction rates in the liver are two fold higher than in the intestine, both in humans and rats. In HLMs, inhibitors of CYP2C9, 3A4/5, 2D6, and 2B6 had strong inhibitory effects on SC formation. Meanwhile, inhibitors of CYP3A and CYP2D6 had significant inhibition on SC formation in RLMs. Human recombinant CYP3A4/5, 2B6, 2D6, and 2C9 contributed significantly to SC production. The permeability in rat intestine and the excretion rates of metabolites were highest in the duodenum (p<0.05), and the absorbed amount of OSC in duodenum and jejunum was concentration-dependent. The metabolism could be significantly decreased by CYP3A inhibitor ketoconazole. In conclusion, the liver was the main organ responsible for OSC metabolism. First-pass metabolism via CYP3A4/5, 2B6, 2D6, and 2C9 may be the main reason for the poor OSC bioavailability.
Collapse
Affiliation(s)
- Lili Wu
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Wanping Zhong
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Junjin Liu
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Weichao Han
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Shilong Zhong
- Medical Research Center of Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong 510080, China
| | - Qiang Wei
- State Key Laboratory of Organ Failure Research, Guangdong Provincial Institute of Nephrology, Southern Medical University, Guangzhou, China
| | - Shuwen Liu
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China; State Key Laboratory of Organ Failure Research, Guangdong Provincial Institute of Nephrology, Southern Medical University, Guangzhou, China.
| | - Lan Tang
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China; State Key Laboratory of Organ Failure Research, Guangdong Provincial Institute of Nephrology, Southern Medical University, Guangzhou, China.
| |
Collapse
|
5
|
Ford KA, Ryslik G, Sodhi J, Halladay J, Diaz D, Dambach D, Masuda M. Computational predictions of the site of metabolism of cytochrome P450 2D6 substrates: comparative analysis, molecular docking, bioactivation and toxicological implications. Drug Metab Rev 2015; 47:291-319. [DOI: 10.3109/03602532.2015.1047026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
6
|
Hata S, Miki Y, Saito R, Ishida K, Watanabe M, Sasano H. Aromatase in human liver and its diseases. Cancer Med 2013; 2:305-15. [PMID: 23930207 PMCID: PMC3699842 DOI: 10.1002/cam4.85] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 03/24/2013] [Accepted: 03/25/2013] [Indexed: 12/19/2022] Open
Abstract
Estrogens play important roles in the cell proliferation and invasion of estrogen-dependent human neoplasms. Aromatase overexpression has been also reported in hepatitis and hepatocellular carcinoma (HCC) compared with normal liver but its details in these hepatic disorders have remained unclear. Therefore, in this study, we first immunolocalized aromatase using immunohistochemistry in patients with liver cirrhosis, steatosis, hepatitis, HCC, and metastasis liver carcinoma (MLC) in order to study the detailed status of intrahepatic aromatase. Aromatase immunoreactivity was predominantly detected in nonneoplastic hepatocytes around tumor cells. We then evaluated the effects of an interaction between hepatocytes and carcinoma cells upon aromatase mRNA expression, using HepG2 as a substitute model of hepatocytes by coculture systems. Aromatase mRNA levels in HepG2 were significantly increased by coculture with all carcinoma cell lines examined. We also evaluated alternative splicing of aromatase exon 1 but the same splicing variant was used in HepG2 cells regardless of carcinoma cell lines employed in the coculture system. These findings obtained in HepG2 indicated that carcinoma cells, whether metastatic or primary, induced aromatase expression in adjacent normal hepatocytes possibly through the soluble aromatase inducible factors in human hepatic microenvironments.
Collapse
Affiliation(s)
- Shuko Hata
- Department of Pathology, Tohoku University Graduate School of Medicine 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
| | | | | | | | | | | |
Collapse
|
7
|
Abstract
The use of organochlorine insecticides such as DDT, lindane and cyclodieneshas declined markedly worldwide over the last decades. Most are now banned or not used. At an acute toxicity level they have been relatively safe in use for humans. However, the greatest concerns are their persistence in people, wildlife and the environment due to their slow metabolism. Although their carcinogenicity for humans has not been supported by strong epidemiological evidence, their potential to be modulators of endocrine and immune function at levels remaining in the environment or associated with residual spraying of DDT continue to be of concern. At present, DDT is still allowed by the United Nations for combating malaria, with continual monitoring and assessment where possible. The toxicological consequences of exposure of animals and people to DDT is discussed as well as some analogues and other insecticides such as lindane, dieldrin and chlordecone that, although little used, continue to persist in surroundings and people. Because of circumstances of world health brought about by climate change or human activities that have yet to develop, there may come a time when the importance of some may re-emerge.
Collapse
Affiliation(s)
- Andrew G Smith
- MRC Toxicology Unit, University of Leicester Lancaster Road, Leicester UK.
| |
Collapse
|
8
|
Rydberg P, Vasanthanathan P, Oostenbrink C, Olsen L. Fast prediction of cytochrome P450 mediated drug metabolism. ChemMedChem 2010; 4:2070-9. [PMID: 19852016 DOI: 10.1002/cmdc.200900363] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cytochrome P450 mediated metabolism of drugs is one of the major determinants of their kinetic profile, and prediction of this metabolism is therefore highly relevant during the drug discovery and development process. A new rule-based method, based on results from density functional theory calculations, for predicting activation energies for aliphatic and aromatic oxidations by cytochromes P450 is developed and compared with several other methods. Although the applicability of the method is currently limited to a subset of P450 reactions, these reactions describe more than 90 % of the metabolites. The rules employed are relatively few and general, and when combined with solvent-accessible surface area calculations to account for steric accessibility, the method gives a major P450 metabolite as first-ranked position for 75 % of the substrates, and ranked in the top three for 90 % of substrates for a set of 20 substrates. In combination with docking, it can predict isoform-specific metabolism, and we apply this on CYP1A2 with very good results on 81 substrates, for which we find a major metabolite ranked in the top three for 90 % of the substrates (100 % in the training set and 87 % in the larger test set).
Collapse
Affiliation(s)
- Patrik Rydberg
- Department of Medicinal Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | | | | | | |
Collapse
|
9
|
Ohyama K, Maki S, Sato K, Kato Y. Comparativein vitrometabolism of the suspected pro-oestrogenic compound, methoxychlor in precision-cut liver slices from male and female rats. Xenobiotica 2008; 35:331-42. [PMID: 16019955 DOI: 10.1080/00498250500087309] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The in vitro metabolism of [14C]methoxychlor (MXC), a suspected pro-oestrogenic compound, by male and female Fischer rats (F344) was compared in precision-cut liver slices. The results demonstrated time-dependent metabolism of MXC with integrated phase I and II reactions, and the sex differences were detected in the metabolic profiles. In liver slices from male rats, MXC was metabolized to bis-demethylated MXC (bis-OH-MXC) by sequential O-demethylation followed by subsequent O-glucuronidation. The doubly conjugated metabolite, bis-OH-MXC 4-O-sulphate 4'-O-glucuronide was additionally produced. In the case of the female rat, the glucuronides of both mono- and bis-OH-MXC were formed as the main metabolites, and the mono-OH-MXC glucuronide appeared to be specific to the female rat. The ratios of bis-/mono-demethylated metabolite, which include the amounts of corresponding conjugates, were approximately 95/5 for the male rats and 40/60 for the female. These results imply that demethylation to the intermediate metabolite, (S)-mono-OH-MXC, is a key step for the sex-dependent metabolism of MXC in the rats. The phase I metabolites produced were extensively conjugated with D-glucuronic acid in both male and female rats.
Collapse
Affiliation(s)
- K Ohyama
- The Institute of Environmental Toxicology, Mitsukaido, Japan.
| | | | | | | |
Collapse
|
10
|
Ohyama K, Maki S, Sato K, Kato Y. In vitrometabolism of [14C]methoxychlor in rat, mouse, Japanese quail and rainbow trout in precision-cut liver slices. Xenobiotica 2008; 34:741-54. [PMID: 15690762 DOI: 10.1080/00498250400003455] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
1. The in vitro metabolism of [14C]methoxychlor (MXC) has been studied using precision-cut liver slices from the Sprague-Dawley male rat, CD-1 male mouse, WE strain male Japanese quail and juvenile rainbow trout (Oncorhynchus mykiss). The results demonstrated integrated phase I and II metabolism of MXC and species differences in the metabolic profiles were observed. 2. In rat liver slice preparations, MXC was rapidly metabolized to bis-OH-MXC by sequential O-demethylation followed by subsequent O-glucuronidation forming bis-OH-MXC glucuronide. No mono-OH-MXC glucuronide was detected. The doubly conjugated metabolite, bis-OH-MXC 4-O-sulphate 4'-O-glucuronide, was also detected as a rat-specific metabolite. 3. Formation of mono-OH-MXC and its glucuronide was the main metabolic pathway in the mouse and Japanese quail. In contrast to the rat, only minor amounts of bis-OH-MXC glucuronide were detected. A reductively dehalogenated metabolite, dechlorinated mono-OH-MXC glucuronide, was observed only in mouse preparations. 4. In rainbow trout, comparative amounts of both mono- and bis-OH-MXC glucuronide were formed as the major metabolites. Unconjugated forms of these metabolites were detected only as minor products. 5. The different metabolic profiles of MXC observed in the four animal species are possibly due to substrate specificity of contributing CYP450 monooxgenase enzyme(s) in different animal species.
Collapse
Affiliation(s)
- K Ohyama
- Institute of Environmental Toxicology, Uchi-moriya 4321, Mitsukaido, Ibaraki 303-0043, Japan.
| | | | | | | |
Collapse
|
11
|
Ohyama K, Maki S, Sato K, Kato Y. Comparative in vitro metabolism of methoxychlor in male and female rats: metabolism of demethylated methoxychlor metabolites by precision-cut rat liver slices. Xenobiotica 2005; 35:683-95. [PMID: 16316928 DOI: 10.1080/00498250500230693] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The in vitro metabolism of demethylated methoxychlor (MXC) metabolites, mono-OH-MXC (including (R)- and (S)-isomers) and bis-OH-MXC (mono- and bis-demethylated MXC, respectively), was conducted using precision-cut liver slices to understand the sex-dependent metabolism of MXC in rats. In the study with bis-OH-MXC, the substrate underwent extensive conjugation producing its glucuronide and glucuronide/sulphate diconjugate, and no significant sex differences were found. On the contrary, the metabolism of mono-OH-MXC appeared to exhibit the sex differences in the metabolic profiles. The bis-OH-MXC glucuronide and glucuronide/sulphate diconjugate were major metabolites in male rat, whereas the mono- and bis-OH-MXC glucuronides predominated in the female. The per cent distribution of the demethylated products (sum of bis-OH-MXC derivatives) was approximately 90% for the male (for both isomers) and 81 (R-) to 56% (S-) for the female. The metabolic profiles in (S)-mono-OH-MXC, which is the predominant enantiomer preferentially produced in MXC metabolism in rats, showed a similar pattern to that of MXC compared with the (R)-isomer. The results indicate that the sex differences in oxidative demethylation of the intermediate, (S)-mono-OH-MXC, could be one of the probable reasons for the sex-dependent metabolism of MXC in rats, and the stereo-structural preference of the contributing demethylase enzymes appear to be involved.
Collapse
Affiliation(s)
- K Ohyama
- Institute of Environmental Toxicology, Ibaraki, Japan.
| | | | | | | |
Collapse
|
12
|
Asano T, Takahashi KA, Fujioka M, Inoue S, Satomi Y, Nishino H, Tanaka T, Hirota Y, Takaoka K, Nakajima S, Kubo T. Genetic analysis of steroid-induced osteonecrosis of the femoral head. J Orthop Sci 2003; 8:329-33. [PMID: 12768474 DOI: 10.1007/s10776-003-0646-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
With advanced organ transplantation technology, steroid-induced osteonecrosis of the femoral head (ONF) is one of the most troublesome complications. Steroid sensitivity varies among individuals, and the involvement of polymorphism of various genes relating to steroid metabolism is suggested. The present study investigated the relation between single nucleotide polymorphism (SNP) on the DNA sequence of cytochrome p(450) and ONF development. The subjects were 80 renal transplant patients. Genome DNA was obtained from the peripheral blood, and SNP analyses for CYP3A4, CYP2D6, and CYP2C19 were conducted using various methods: direct sequencing, polymerase chain reaction restriction fragment length polymorphism, and DNA Chip. The relation between ONF development and SNP was statistically analyzed. It is useful if the generating risk judged according to SNPs to prevention of steroid-induced ONF is possible. This time, SNPs, which are clearly related to ONF, were not accepted, although the possibility that SNP related to steroid metabolism is involved in ONF development is important. We think that it is necessary to examine this area more closely.
Collapse
Affiliation(s)
- Takeshi Asano
- Department of Orthopaedic Surgery, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Zamora I, Afzelius L, Cruciani G. Predicting drug metabolism: a site of metabolism prediction tool applied to the cytochrome P450 2C9. J Med Chem 2003; 46:2313-24. [PMID: 12773036 DOI: 10.1021/jm021104i] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The aim of the present study is to develop a method for predicting the site at which molecules will be metabolized by CYP 2C9 (cytochrome P450 2C9) using a previously reported protein homology model of the enzyme. Such a method would be of great help in designing new compounds with a better pharmacokinetic profile, or in designing prodrugs where the compound needs to be metabolized in order to become active. The methodology is based on a comparison between alignment-independent descriptors derived from GRID Molecular Interaction Fields for the CYP 2C9 active site, and a distance-based representation of the substrate. The predicted site of metabolism is reported as a ranking list of all the hydrogen atoms of each substrate molecule. Eighty-seven CYP 2C9-catalyzed oxidative reactions reported in the literature have been analyzed. In more than 90% of these cases, the hydrogen atom ranked at the first, second, or third position was the experimentally reported site of oxidation.
Collapse
Affiliation(s)
- Ismael Zamora
- Drug Metabolism, Pharmacokinetic and Bioanalytical Chemistry, AstraZeneca R&D Mölndal, Sweden.
| | | | | |
Collapse
|
14
|
Abstract
This chapter is an update of the data on substrates, reactions, inducers, and inhibitors of human CYP enzymes published previously by Rendic and DiCarlo (1), now covering selection of the literature through 2001 in the reference section. The data are presented in a tabular form (Table 1) to provide a framework for predicting and interpreting the new P450 metabolic data. The data are formatted in an Excel format as most suitable for off-line searching and management of the Web-database. The data are presented as stated by the author(s) and in the case when several references are cited the data are presented according to the latest published information. The searchable database is available either as an Excel file (for information contact the author), or as a Web-searchable database (Human P450 Metabolism Database, www.gentest.com) enabling the readers easy and quick approach to the latest updates on human CYP metabolic reactions.
Collapse
Affiliation(s)
- Slobodan Rendic
- Faculty of Pharmacy and Biochemistry, University of Zagreb, Croatia.
| |
Collapse
|