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El-Ghiaty MA, El-Mahrouk SR, Alqahtani MA, El-Kadi AOS. Differential modulation of cytochrome P450 enzymes by arsenicals in non-human experimental models. Drug Metab Rev 2023; 55:405-427. [PMID: 37679937 DOI: 10.1080/03602532.2023.2254525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 08/24/2023] [Indexed: 09/09/2023]
Abstract
Arsenic is a hazardous heavy metalloid that imposes threats to human health globally. It is widely spread throughout the environment in various forms. Arsenic-based compounds are either inorganic compounds (iAs) or organoarsenicals (oAs), where the latter are biotically generated from the former. Exposure to arsenic-based compounds results in varying biochemical derangements in living systems, leading eventually to toxic consequences. One important target for arsenic in biosystems is the network of metabolic enzymes, especially the superfamily of cytochrome P450 enzymes (CYPs) because of their prominent role in both endobiotic and xenobiotic metabolism. Therefore, the alteration of the CYPs by different arsenicals has been actively studied in the last few decades. We have previously summarized the findings of former studies investigating arsenic associated modulation of different CYPs in human experimental models. In this review, we focus on non-human models to get a complete picture about possible CYPs alterations in response to arsenic exposure.
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Affiliation(s)
- Mahmoud A El-Ghiaty
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Sara R El-Mahrouk
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Mohammed A Alqahtani
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Ayman O S El-Kadi
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
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2
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Hsieh CH, Chen YJ, Tsai TH, Wang LY, Tai HC, Huang HL, Huang YC. Robust combination of liver stereotactic body radiotherapy modulates pharmacokinetics of sorafenib toward preferable parameters. Sci Rep 2020; 10:9575. [PMID: 32533042 PMCID: PMC7293270 DOI: 10.1038/s41598-020-66583-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 05/21/2020] [Indexed: 01/15/2023] Open
Abstract
To evaluate the effect and mechanism of radiotherapy (RT)–sorafenib pharmacokinetics (PK) in different regimens with conventional or high dose irradiation. Between February 2012 and December 2018, 43 patients with portal vein tumor thrombosis treated with sorafenib plus conventional RT (58%) or stereotactic body radiation therapy (SBRT, 42%) were retrospectively reviewed. In vivo and in vitro studies of concurrent and sequential RT with sorafenib were designed. SBRT resulted in a 3-fold increase in complete recanalization compared to conventional RT group (28% vs. 8%, p = 0.014). Compared to the control group, the area under the concentration vs. time curve (AUC) of sorafenib was increased in the concurrent RT2Gy and RT9Gy groups and the sequential RT9Gy group by 132% (p = 0.046), 163% (p = 0.038) and 102% (p = 0.018), respectively; and was decreased by 59% in the sequential RT2Gy group (p = 0.036). Sequential RT2Gy and RT9Gy increased CYP3A4 activity by 82% (p = 0.028) and 203% (p = 0.0004), respectively, compared to that with the corresponding concurrent regimen. SBRT produced better recanalization than conventional RT with sorafenib. The AUC of sorafenib was modulated by RT. P-gp expression was not influenced by RT. The sequential RT regimen increased CYP3A4 activity that may increase the RT-sorafenib synergy effect and overall sorafenib activity. The biodistribution of sorafenib was modulated by local RT with the different regimens.
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Affiliation(s)
- Chen-Hsi Hsieh
- Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan. .,Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan. .,Division of Radiation Oncology, Department of Radiology, Far Eastern Memorial Hospital, Taipei, Taiwan.
| | - Yu-Jen Chen
- Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.,Department of Radiation Oncology, Mackay Memorial Hospital, Taipei, Taiwan.,Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan
| | - Tung-Hu Tsai
- Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.,Department of Chemical Engineering, National United University, Miaoli, Taiwan
| | - Li-Ying Wang
- School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University, Taipei, Taiwan.,Physical Therapy Center, National Taiwan University Hospital, Taipei, Taiwan
| | - Hung-Chi Tai
- Department of Radiation Oncology, Mackay Memorial Hospital, Taipei, Taiwan
| | - Hsiang-Ling Huang
- Division of Radiation Oncology, Department of Radiology, Far Eastern Memorial Hospital, Taipei, Taiwan
| | - Yu-Chuen Huang
- Department of Medical Research, China Medical University Hospital, Taichung, Taiwan.,School of Chinese Medicine, China Medical University, Taichung, Taiwan
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Mo X, Li J, Liu Y, Liao X, Tan M, Chen Y, He F, He Y, Li Y, Huang M. Kidney podocyte-associated gene polymorphisms affect tacrolimus concentration in pediatric patients with refractory nephrotic syndrome. THE PHARMACOGENOMICS JOURNAL 2020; 20:543-552. [PMID: 31902946 DOI: 10.1038/s41397-019-0141-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 11/24/2019] [Accepted: 12/16/2019] [Indexed: 12/11/2022]
Abstract
Few studies have investigated the correlation between pharmacogenomics and tacrolimus pharmacokinetics in patients with nephrotic syndrome (NS). This study evaluated the influences of genetic polymorphisms of metabolic enzymes, transporters, and podocyte-associated proteins on tacrolimus concentration in Chinese pediatric patients with refractory NS. A total of 167 pediatric patients with refractory NS were included from July 2013 to December 2017. Age of onset was restricted to <14 years of age. Dose-adjusted tacrolimus trough concentration (C0/D) on the third month was calculated, and 20 single-nucleotide polymorphisms in sixteen genes were genotyped. Age was correlated with tacrolimus C0/D (p = 0.006, r = 0.213). Tacrolimus C0/D was higher in CYP3A5 nonexpressers than in CYP3A5 expressers (p = 0.003). ACTN4 rs62121818, MYH9 rs2239781, CYP3A5*3, and age explained 20.5% interindividual variability of tacrolimus concentration in the total cohort. In CYP3A5 nonexpressers, ACTN4 rs62121818 and MYH9 rs2239781 together explained 14.6% variation of tacrolimus C0/D. MYH9 rs2239781, LAMB2 rs62119873 and age together explained 22.3% variability of tacrolimus level in CYP3A5 expressers. CYP3A5*3 was still an important factor affecting tacrolimus concentration in patients with NS. Podocyte-associated gene polymorphisms, especially ACTN4 rs62121818 and MYH9 rs2239781, were the other most important biomarkers for tacrolimus whole blood levels. Genotyping of CYP3A5, ACTN4, and MYH9 polymorphisms may be helpful for better guiding tacrolimus dosing in pediatric patients with refractory NS.
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Affiliation(s)
- Xiaolan Mo
- Institute of Clinical Pharmacology, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China.,Department of Pharmacy, Guangzhou Women and Children's medical center, Guangzhou Medical University, Guangzhou, China
| | - Jiali Li
- Institute of Clinical Pharmacology, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Yunfeng Liu
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Xin Liao
- Division of nephrology, Guangzhou Women and Children's medical center, Guangzhou Medical University, Guangzhou, China
| | - Mei Tan
- Division of nephrology, Guangzhou Women and Children's medical center, Guangzhou Medical University, Guangzhou, China
| | - Yilu Chen
- Department of Pharmacy, Guangzhou Women and Children's medical center, Guangzhou Medical University, Guangzhou, China
| | - Fan He
- Department of Pharmacy, Guangzhou Women and Children's medical center, Guangzhou Medical University, Guangzhou, China
| | - Yanling He
- Department of Pharmacy, Guangzhou Women and Children's medical center, Guangzhou Medical University, Guangzhou, China.
| | - Yingjie Li
- Division of nephrology, Guangzhou Women and Children's medical center, Guangzhou Medical University, Guangzhou, China.
| | - Min Huang
- Institute of Clinical Pharmacology, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China.
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Zhang J, Xie Q, Kong W, Wang Z, Wang S, Zhao K, Chen Y, Liu X, Liu L. Short-chain fatty acids oppositely altered expressions and functions of intestinal cytochrome P4503A and P-glycoprotein and affected pharmacokinetics of verapamil following oral administration to rats. J Pharm Pharmacol 2019; 72:448-460. [PMID: 31863502 DOI: 10.1111/jphp.13215] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 11/24/2019] [Indexed: 12/26/2022]
Abstract
OBJECTIVES To investigate effects of short-chain fatty acids (SCFAs) on expressions and functions of intestinal cytochrome P4503A (Cyp3a) and P-glycoprotein (P-gp). To develop a semi-physiologically based pharmacokinetic (semi-PBPK) model for assessing their contributions. METHODS Verapamil pharmacokinetics was investigated following oral administration to rats receiving water containing 150 mm SCFAs for 3 weeks. Cyp3a activities in intestinal and liver mircosomes were assessed by norverapamil formation. In-situ single-pass perfusion was used to evaluate intestinal transport of verapamil and P-gp function. Functions and expressions of Cyp3a and P-gp were measured in mouse primary enterocytes following 48-h exposure to SCFAs. Contributions of intestinal P-gp and Cyp3a to verapamil pharmacokinetics were assessed using a semi-PBPK model. KEY FINDINGS Short-chain fatty acids significantly increased oral plasma exposures of verapamil and norverapamil. SCFAs upregulated Cyp3a activity and expression, but downregulated P-gp function and expression in rat intestine, which were repeated in mouse primary enterocytes. PBPK simulation demonstrated contribution of intestinal Cyp3a to oral plasma verapamil exposure was minor, and the increased oral plasma verapamil exposure was mainly attributed to downregulation of intestinal P-gp. CONCLUSIONS Short-chain fatty acids oppositely regulated functions and expressions of intestinal Cyp3a and P-gp. The downregulation of P-gp mainly contributed to the increased oral plasma verapamil exposure by SCFAs.
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Affiliation(s)
- Jiaxin Zhang
- Center of Drug Metabolism and Pharmacokinetics, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Qiushi Xie
- Center of Drug Metabolism and Pharmacokinetics, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Weimin Kong
- Center of Drug Metabolism and Pharmacokinetics, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Zhongjian Wang
- Center of Drug Metabolism and Pharmacokinetics, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Shuting Wang
- Center of Drug Metabolism and Pharmacokinetics, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Kaijing Zhao
- Center of Drug Metabolism and Pharmacokinetics, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Yang Chen
- Center of Drug Metabolism and Pharmacokinetics, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Xiaodong Liu
- Center of Drug Metabolism and Pharmacokinetics, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Li Liu
- Center of Drug Metabolism and Pharmacokinetics, School of Pharmacy, China Pharmaceutical University, Nanjing, China
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Jonsson-Schmunk K, Schafer SC, Croyle MA. Impact of nanomedicine on hepatic cytochrome P450 3A4 activity: things to consider during pre-clinical and clinical studies. JOURNAL OF PHARMACEUTICAL INVESTIGATION 2017. [DOI: 10.1007/s40005-017-0376-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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He L, Li H, Huang N, Zhou X, Tian J, Li T, Wu J, Tian Y, Yin Y, Yao K. Alpha-ketoglutarate suppresses the NF-κB-mediated inflammatory pathway and enhances the PXR-regulated detoxification pathway. Oncotarget 2017; 8:102974-102988. [PMID: 29262538 PMCID: PMC5732704 DOI: 10.18632/oncotarget.16875] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Accepted: 03/17/2017] [Indexed: 01/18/2023] Open
Abstract
Alpha-ketoglutarate (AKG) is a critical nutritional factor in the maintenance of intestinal homeostasis. However, the relative mechanism of AKG has not been well understood. It was recently shown that the interaction between nuclear factor kappa B (NF-κB)-mediated inflammatory pathway and pregnane X receptor (PXR)-regulated detoxification pathway is a check and balance mechanism for keeping the homeostatic state of the intestine, preventing the onset of intestinal inflammation which may lead to cancer. In the current study we used lipopolysaccharide (LPS)-challenged piglet and intestinal porcine epithelial cells-J2 models to investigate the effects of dietary AKG supplementation on the intestinal immune system and PXR regulated target expression. We found that LPS induced significant activation of the NF-κB-mediated inflammatory pathway with concomitant impairment of intestinal nutrient absorption. AKG administration increased intracellular AKG and its metabolite concentrations and enhanced the mRNA expression of alpha-ketoglutarate dehydrogenase in vivo and in vitro. Thus dietary AKG supplementation reversed the adverse effects induced by LPS. We also found a strong inhibitory effects on the NF-κB-mediated inflammatory pathway, especially, in the AKG-treated intestinal tissues, LPS-induced NF-κB phosphorylation was inhibited and TNF-α was suppressed. Interestingly, AKG has potent effects in regulating the PXR and its downstream targets such as CYP3As and CYP2Bs in vivo and in vitro, although AKG is not a known PXR ligand. One potential mechanism for the up-regulation of the PXR pathway is through the down-regulation of NF-κB pathway which in turn de-represses the PXR-regulated target expression. Taken together, our results suggest that AKG improves intestinal immune system through modulating the interaction between PXR and NF-κB. Our findings have important implications for the prevention and treatment of intestinal inflammatory diseases in neonates.
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Affiliation(s)
- Liuqin He
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Changsha, Hunan 410125, China.,University of Chinese Academy of Sciences, Huairou, Beijing 10008, China
| | - Huan Li
- College of Animal Science and Technology, Hunan Agricultural University, Hunan, Changsha 410128, China
| | - Niu Huang
- College of Animal Science and Technology, Hunan Agricultural University, Hunan, Changsha 410128, China
| | - Xihong Zhou
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Changsha, Hunan 410125, China
| | - Junquan Tian
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Changsha, Hunan 410125, China.,University of Chinese Academy of Sciences, Huairou, Beijing 10008, China
| | - Tiejun Li
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Changsha, Hunan 410125, China.,Hunan Co-Innovation Center of Animal Production Safety, Hunan, Changsha 410128, China
| | - Jing Wu
- College of Animal Science and Technology, Hunan Agricultural University, Hunan, Changsha 410128, China
| | - Yanan Tian
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX 77843, USA
| | - Yulong Yin
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Changsha, Hunan 410125, China.,Hunan Co-Innovation Center of Animal Production Safety, Hunan, Changsha 410128, China
| | - Kang Yao
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Changsha, Hunan 410125, China.,Hunan Co-Innovation Center of Animal Production Safety, Hunan, Changsha 410128, China
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7
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Vrzal R, Dvorak Z. The comparative effects of diethyldithiocarbamate-copper complex with established proteasome inhibitors on expression levels of CYP1A2/3A4 and their master regulators, aryl hydrocarbon and pregnane X receptor in primary cultures of human hepatocytes. Fundam Clin Pharmacol 2016; 30:585-595. [PMID: 27414036 DOI: 10.1111/fcp.12221] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Revised: 06/20/2016] [Accepted: 07/12/2016] [Indexed: 12/16/2022]
Abstract
In the recent years, a therapeutic potential of disulfiram (Antabuse) complex with copper, as an anticancer drug, was recognized towards several cancer cell lines. The proteasome was suggested as one of the cellular targets for this compound. As the therapeutic use of diethyldithiocarbamate-copper complex (CuET) is expected to increase, it is of great interest to know whether this compound may be the source of drug-drug interactions via the induction of biotransformation enzymes, especially cytochromes P450 (CYPs). To this purpose, we examined the effect of CuET and compared it with typical inducers (rifampicin and dioxin) of CYPs and with well-established proteasome inhibitors (MG132 and bortezomib). Diethyldithiocarbamate-copper complex revealed inconsistent and rather modulatory effect on the expression of CYP1A2 and CYP3A4 in several cultures of human hepatocytes. Moreover, it was able to cause neither ubiquitin accumulation nor significant and dose-dependent inhibition of proteasome activity. It had no effect on essential transcription factors involved in regulation of selected CYPs, aryl hydrocarbon (AhR) nor pregnane X receptor (PXR). However, the AhR protein was increased in majority of examined hepatocyte cultures. The main finding of this study is that: (i) disulfiram-copper complex is not the cause of drug-drug interactions via CYP1A2/3A4 induction; (ii) proteasome inhibitors may have different impact on studied parameters in given in vitro system.
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Affiliation(s)
- Radim Vrzal
- Department of Cell Biology and Genetics, Faculty of Science, Palacky University, Slechtitelu 27, Olomouc, 783 71, Czech Republic
| | - Zdenek Dvorak
- Department of Cell Biology and Genetics, Faculty of Science, Palacky University, Slechtitelu 27, Olomouc, 783 71, Czech Republic
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Jonsson-Schmunk K, Wonganan P, Choi JH, Callahan SM, Croyle MA. Integrin Receptors Play a Key Role in the Regulation of Hepatic CYP3A. ACTA ACUST UNITED AC 2016; 44:758-70. [PMID: 26868618 DOI: 10.1124/dmd.115.068874] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 02/10/2016] [Indexed: 12/21/2022]
Abstract
Landmark studies describing the effect of microbial infection on the expression and activity of hepatic CYP3A used bacterial lipopolysaccharide as a model antigen. Our efforts to determine whether these findings were translatable to viral infections led us to observations suggesting that engagement of integrin receptors is key in the initiation of processes responsible for changes in hepatic CYP3A4 during infection and inflammation. Studies outlined in this article were designed to evaluate whether engagement of integrins, receptors commonly used by a variety of microbes to enter cellular targets, is vital in the regulation of CYP3A in the presence and absence of virus infection. Mice infected with a recombinant adenovirus (AdlacZ) experienced a 70% reduction in hepatic CYP3A catalytic activity. Infection with a mutant virus with integrin-binding arginine-glycine-aspartic acid (RGD) sequences deleted from the penton base protein of the virus capsid (AdΔRGD) did not alter CYP3A activity. CYP3A mRNA and protein levels in AdlacZ-treated animals were also suppressed, whereas those of mice given AdΔRGD were not significantly different from uninfected control mice. Silencing of the integrinβ-subunit reverted adenovirus-mediated CYP3A4 suppression in vitro. Silencing of theα-subunit did not. Suppression of integrin subunits had a profound effect on nuclear receptors pregnane X receptor and constitutive androstane receptor, whereas retinoid X receptorαwas largely unaffected. To our knowledge, this is the first time that extracellular receptors, like integrins, have been indicated in the regulation of CYP3A. This finding has several implications owing to the important role of integrins in normal physiologic process and in many disease states.
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Affiliation(s)
- Kristina Jonsson-Schmunk
- Division of Pharmaceutics, College of Pharmacy (K.J.-S., P.W., J.H.C., S.M.C., M.A.C.), and Center for Infectious Disease (M.A.C.), The University of Texas at Austin, Austin, Texas
| | - Piynauch Wonganan
- Division of Pharmaceutics, College of Pharmacy (K.J.-S., P.W., J.H.C., S.M.C., M.A.C.), and Center for Infectious Disease (M.A.C.), The University of Texas at Austin, Austin, Texas
| | - Jin Huk Choi
- Division of Pharmaceutics, College of Pharmacy (K.J.-S., P.W., J.H.C., S.M.C., M.A.C.), and Center for Infectious Disease (M.A.C.), The University of Texas at Austin, Austin, Texas
| | - Shellie M Callahan
- Division of Pharmaceutics, College of Pharmacy (K.J.-S., P.W., J.H.C., S.M.C., M.A.C.), and Center for Infectious Disease (M.A.C.), The University of Texas at Austin, Austin, Texas
| | - Maria A Croyle
- Division of Pharmaceutics, College of Pharmacy (K.J.-S., P.W., J.H.C., S.M.C., M.A.C.), and Center for Infectious Disease (M.A.C.), The University of Texas at Austin, Austin, Texas
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Chen J, Zhao KN, Chen C. The role of CYP3A4 in the biotransformation of bile acids and therapeutic implication for cholestasis. ANNALS OF TRANSLATIONAL MEDICINE 2014; 2:7. [PMID: 25332983 DOI: 10.3978/j.issn.2305-5839.2013.03.02] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 03/11/2013] [Indexed: 12/23/2022]
Abstract
CYP3A4 is a major cytochrome P450. It catalyses a broad range of substrates including xenobiotics such as clinically used drugs and endogenous compounds bile acids. Its function to detoxify bile acids could be used for treating cholestasis, which is a condition characterised by accumulation of bile acids. Although bile acids have important physiological functions, they are very toxic when their concentrations are excessively high. The accumulated bile acids in cholestasis can cause liver and other tissue injuries. Thus, control of the concentrations of bile acids is critical for treatment of cholestasis. CYP3A4 is responsively upregulated in cholestasis mediated by the nuclear receptors farnesol X receptor (FXR) and pregnane X receptor (PXR) as a defence mechanism. However, the regulation of CYP3A4 is complicated by estrogen, which is increased in cholestasis and down regulates CYP3A4 expression. The activity of CYP3A4 is also inhibited by accumulated bile acids due to their property of detergent effect. In some cholestasis cases, genetic polymorphisms of the CYP3A4 and PXR genes may interfere with the adaptive response. Further stimulation of CYP3A4 activity in cholestasis could be an effective approach for treatment of the disease. In this review, we summarise recent progress about the roles of CYP3A4 in the metabolism of bile acids, its regulation and possible implication in the treatment of cholestasis.
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Affiliation(s)
- Jiezhong Chen
- 1 School of Biomedical Sciences, University of Queensland, St Lucia, QLD 4072, Australia ; 2 Centre for Kidney Disease-Venomics Research, School of Medicine, University of Queensland, Princess Alexandra Hospital, Woolloongabba, Brisbane, QLD 4102, Australia
| | - Kong-Nan Zhao
- 1 School of Biomedical Sciences, University of Queensland, St Lucia, QLD 4072, Australia ; 2 Centre for Kidney Disease-Venomics Research, School of Medicine, University of Queensland, Princess Alexandra Hospital, Woolloongabba, Brisbane, QLD 4102, Australia
| | - Chen Chen
- 1 School of Biomedical Sciences, University of Queensland, St Lucia, QLD 4072, Australia ; 2 Centre for Kidney Disease-Venomics Research, School of Medicine, University of Queensland, Princess Alexandra Hospital, Woolloongabba, Brisbane, QLD 4102, Australia
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Hu N, Hu M, Duan R, Liu C, Guo H, Zhang M, Yu Y, Wang X, Liu L, Liu X. Increased Levels of Fatty Acids Contributed to Induction of Hepatic CYP3A4 Activity Induced by Diabetes — In Vitro Evidence From HepG2 Cell and Fa2N-4 Cell Lines. J Pharmacol Sci 2014; 124:433-44. [DOI: 10.1254/jphs.13212fp] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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11
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Wang Z, Yang J, Kirk C, Fang Y, Alsina M, Badros A, Papadopoulos K, Wong A, Woo T, Bomba D, Li J, Infante JR. Clinical Pharmacokinetics, Metabolism, and Drug-Drug Interaction of Carfilzomib. Drug Metab Dispos 2012; 41:230-7. [DOI: 10.1124/dmd.112.047662] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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12
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Zangar RC, Bollinger N, Weber TJ, Tan RM, Markillie LM, Karin NJ. Reactive oxygen species alter autocrine and paracrine signaling. Free Radic Biol Med 2011; 51:2041-7. [PMID: 21963990 PMCID: PMC3219223 DOI: 10.1016/j.freeradbiomed.2011.09.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Revised: 09/01/2011] [Accepted: 09/01/2011] [Indexed: 12/12/2022]
Abstract
Cytochrome P450 (P450) 3A4 (CYP3A4) is the most abundant P450 protein in human liver and intestine and is highly inducible by a variety of drugs and other compounds. The P450 catalytic cycle is known to uncouple and release reactive oxygen species (ROS), but the effects of ROS from P450 and other enzymes in the endoplasmic reticulum have been poorly studied from the perspective of effects on cell biology. In this study, we expressed low levels of CYP3A4 in HepG2 cells, a human hepatocarcinoma cell line, and examined effects on intracellular levels of ROS and on the secretion of a variety of growth factors that are important in extracellular communication. Using the redox-sensitive dye RedoxSensor red, we demonstrate that CYP3A4 expression increases levels of ROS in viable cells. A custom ELISA microarray platform was employed to demonstrate that expression of CYP3A4 increased secretion of amphiregulin, intracellular adhesion molecule 1, matrix metalloprotease 2, platelet-derived growth factor (PDGF), and vascular endothelial growth factor, but suppressed secretion of CD14. The antioxidant N-acetylcysteine suppressed all P450-dependent changes in protein secretion except for CD14. Quantitative RT-PCR demonstrated that changes in protein secretion were consistently associated with corresponding changes in gene expression. Inhibition of the NF-κB pathway blocked P450 effects on PDGF secretion. CYP3A4 expression also altered protein secretion in human mammary epithelial cells and C10 mouse lung cells. Overall, these results suggest that increased ROS production in the endoplasmic reticulum alters the secretion of proteins that have key roles in paracrine and autocrine signaling.
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Affiliation(s)
- Richard C Zangar
- Cell Biology and Biochemistry, Pacific Northwest National Laboratory, Richland, WA 99354, USA.
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Jin H, Webb-Robertson BJ, Peterson ES, Tan R, Bigelow DJ, Scholand MB, Hoidal JR, Pounds JG, Zangar RC. Smoking, COPD, and 3-nitrotyrosine levels of plasma proteins. ENVIRONMENTAL HEALTH PERSPECTIVES 2011; 119:1314-1320. [PMID: 21652289 PMCID: PMC3230408 DOI: 10.1289/ehp.1103745] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 06/06/2011] [Indexed: 05/30/2023]
Abstract
BACKGROUND Nitric oxide is a physiological regulator of endothelial function and hemodynamics. Oxidized products of nitric oxide can form nitrotyrosine, which is a marker of nitrative stress. Cigarette smoking decreases exhaled nitric oxide, and the underlying mechanism may be important in the cardiovascular toxicity of smoking. Even so, it is unclear if this effect results from decreased nitric oxide production or increased oxidative degradation of nitric oxide to reactive nitrating species. These two processes would be expected to have opposite effects on nitrotyrosine levels, a marker of nitrative stress. OBJECTIVE In this study, we evaluated associations of cigarette smoking and chronic obstructive pulmonary disease (COPD) with nitrotyrosine modifications of specific plasma proteins to gain insight into the processes regulating nitrotyrosine formation. METHODS A custom antibody microarray platform was developed to analyze the levels of 3-nitrotyrosine modifications on 24 proteins in plasma. In a cross-sectional study, plasma samples from 458 individuals were analyzed. RESULTS Average nitrotyrosine levels in plasma proteins were consistently lower in smokers and former smokers than in never smokers but increased in smokers with COPD compared with smokers who had normal lung-function tests. CONCLUSIONS Smoking is associated with a broad decrease in 3-nitrotyrosine levels of plasma proteins, consistent with an inhibitory effect of cigarette smoke on endothelial nitric oxide production. In contrast, we observed higher nitrotyrosine levels in smokers with COPD than in smokers without COPD. This finding is consistent with increased nitration associated with inflammatory processes. This study provides insight into a mechanism through which smoking could induce endothelial dysfunction and increase the risk of cardiovascular disease.
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Affiliation(s)
- Hongjun Jin
- Cell Biology and Biochemistry, Pacific Northwest National Laboratory, Richland, Washington 99354, USA
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14
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Dvorak Z, Pavek P. Regulation of drug-metabolizing cytochrome P450 enzymes by glucocorticoids. Drug Metab Rev 2011; 42:621-35. [PMID: 20482443 DOI: 10.3109/03602532.2010.484462] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The regulation of drug-metabolizing cytochrome P450 enzymes (CYP) is a complex process involving multiple mechanisms. Among them, transcriptional regulation through ligand-activated nuclear receptors is the crucial mechanism involved in hormone-controlled and xenobiotic-induced expression of drug-metabolizing CYPs. In this article, we focus, in detail, on the role of the glucocorticoid receptor (GR) in the transcriptional regulation of human drug-metabolizing CYP enzymes and the mechanisms of the regulation. There are at least three distinct transcriptional mechanisms by which GR controls the expression of CYPs: 1) direct binding of GR to a specific gene-promoter sequence called the glucocorticoid responsive element (GRE); 2) indirect binding of GR in the form of a multiprotein complex to gene promoters without a direct contact between GR and promoter DNA; and 3) up- or downregulation of other CYP transcriptional regulators or nuclear receptors (i.e., transcriptional regulatory cross-talk). However, due to the general effect of glucocorticoids on numerous cellular pathways and functions, the net transcriptional effect of glucocorticoids on drug-metabolizing enzymes is usually a combination of several mechanisms. Since synthetic glucocorticoids are widely prescribed in human pharmacotherapy for the treatment of many diseases, comprehensive understanding of the transcriptional regulation of drug-metabolizing CYPs via GR with respect to glucocorticoid therapy or glucocorticoid hormonal status will aid in the development of efficient individualized pharmacotherapy without drug-drug interactions.
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Affiliation(s)
- Zdenek Dvorak
- Department of Cell Biology and Genetics, Faculty of Science, Palacky University, Olomouc, Czech Republic.
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15
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Donato MT, Hallifax D, Picazo L, Castell JV, Houston JB, Gomez-Lechón MJ, Lahoz A. Metabolite formation kinetics and intrinsic clearance of phenacetin, tolbutamide, alprazolam, and midazolam in adenoviral cytochrome P450-transfected HepG2 cells and comparison with hepatocytes and in vivo. Drug Metab Dispos 2010; 38:1449-55. [PMID: 20501911 DOI: 10.1124/dmd.110.033605] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Cryopreserved human hepatocytes and other in vitro systems often underpredict in vivo intrinsic clearance (CL(int)). The aim of this study was to explore the potential utility of HepG2 cells transduced with adenovirus vectors expressing a single cytochrome P450 enzyme (Ad-CYP1A2, Ad-CYP2C9, or Ad-CYP3A4) for metabolic clearance predictions. The kinetics of metabolite formation from phenacetin, tolbutamide, and alprazolam and midazolam, selected as substrates probes for CYP1A2, CYP2C9, and CYP3A4, respectively, were characterized in this in vitro system. The magnitude of the K(m) or S(50) values observed in Ad-P450 cells was similar to those found in the literature for other human liver-derived systems. For each substrate, CL(int) (or CL(max)), values from Ad-P450 systems were scaled to human hepatocytes in primary culture using the relative activity factor (RAF) approach. Scaled Ad-P450 CL(int) values were approximately 3- to 6-fold higher (for phenacetin O-deethylation, tolbutamide 4-hydroxylation, and alprazolam 4-hydroxyaltion) or lower (midazolam 1'-hydroxylation) than those reported for human cryopreserved hepatocytes in suspension. Comparison with the in vivo data reveals that Ad-P450 cells provide a favorable prediction of CL(int) for the substrates studied (in a range of 20-200% in vivo observed CL(int)). This is an improvement compared with the consistent underpredictions (<10-50% in in vivo observed CL(int)) found in cryopreserved hepatocyte studies with the same substrates. These results suggest that the Ad-P450 cell is a promising in vitro system for clearance predictions of P450-metabolized drugs.
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Affiliation(s)
- M Teresa Donato
- Unidad de Hepatología Experimental, Centro de Investigación, Hospital La Fe, Avenida Campanar 21, Valencia, Spain.
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16
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Croyle MA. Long-term virus-induced alterations of CYP3A-mediated drug metabolism: a look at the virology, immunology and molecular biology of a multi-faceted problem. Expert Opin Drug Metab Toxicol 2009; 5:1189-211. [PMID: 19732028 DOI: 10.1517/17425250903136748] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Virus infections are on the rise. Although the first description of CYP expression during virus infection was recorded 50 years ago, mechanistic studies of this phenomenon only began to appear in the last decade due to breakthroughs in molecular biology, genomic and transgenic technology. This review describes the relationship(s) among CYP-mediated drug metabolism, virus infection and the immune response and evaluates in vitro and in vivo models for mechanistic studies. The first studies that assessed CYP expression during infection focused on inflammatory mediators and the innate immune response at early time points. Recent studies assessing virus infection and its effect on hepatic CYP expression noted more long-term effects. An obvious approach toward understanding how viruses affect hepatic CYP3A expression and function would be to assess key regulators of CYP during infection. Improvements in techniques to identify post-translational modifications of CYP and systems that focus on virus-receptor interactions which allow subtraction and addition of immunological and regulatory elements that drive CYP will demonstrate that long-term changes in drug metabolism start from the time the virus enters the circulation, are reinforced by virus binding to cellular targets and further solidified by changes in cellular processes long after the virus is cleared.
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Affiliation(s)
- Maria A Croyle
- The University of Texas at Austin, College of Pharmacy, Division of Pharmaceutics and Institute of Cellular and Molecular Biology, PHR 4.214D, 2409 W University Avenue, Austin, TX 78712-1074, USA.
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17
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Zangar RC, Daly DS, White AM, Servoss SL, Tan RM, Collett JR. ProMAT calibrator: A tool for reducing experimental bias in antibody microarrays. J Proteome Res 2009; 8:3937-43. [PMID: 19618941 DOI: 10.1021/pr900247n] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Our research group has been developing enzyme-linked immunosorbent assays (ELISA) microarray technology for the rapid and quantitative evaluation of biomarker panels. Studies using antibody microarrays are susceptible to systematic bias from the various steps in the experimental process, and these biases can mask biologically significant differences. For this reason, we have developed a calibration system that can identify and reduce systematic bias due to processing factors. Specifically, we developed a sandwich ELISA for green fluorescent protein (GFP) that is included on each chip. The GFP antigen is spiked into each biological sample or standard mixture and the resulting signal is used for calibration between chips. We developed ProMAT Calibrator, an open-source bioinformatics tool, for the rapid visualization and interpretation of the calibrator data and, if desired, data normalization. We demonstrate that data normalization using this system markedly reduces bias from processing factors. Equally useful, this calibrator system can help reveal the source of the bias, thereby facilitating the elimination of the underlying problem. ProMAT Calibrator can be downloaded at http://www.pnl.gov/statistics/ProMAT .
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Affiliation(s)
- R C Zangar
- Pacific Northwest National Laboratory, Richland, Washington 99354, USA.
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Sugawara M, Okamoto K, Kadowaki T, Kusano K, Fukamizu A, Yoshimura T. Inoculation of Human Tumor Cells Alters the Basal Expression but Not the Inducibility of Cytochrome P450 Enzymes in Tumor-Bearing Mouse Liver. Drug Metab Dispos 2009; 37:2244-54. [DOI: 10.1124/dmd.109.028571] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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19
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Acharya P, Engel JC, Correia MA. Hepatic CYP3A suppression by high concentrations of proteasomal inhibitors: a consequence of endoplasmic reticulum (ER) stress induction, activation of RNA-dependent protein kinase-like ER-bound eukaryotic initiation factor 2alpha (eIF2alpha)-kinase (PERK) and general control nonderepressible-2 eIF2alpha kinase (GCN2), and global translational shutoff. Mol Pharmacol 2009; 76:503-15. [PMID: 19520899 DOI: 10.1124/mol.109.056002] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Hepatic cytochromes P450 3A (P450s 3A) are endoplasmic reticulum (ER)-proteins, responsible for xenobiotic metabolism. They are degraded by the ubiquitin-dependent 26S proteasome. Consistent with this, we have shown that proteasomal inhibitors N-benzoyloxycarbonyl (Z)-Leu-Leu-leucinal (MG132) and N-benzoyloxycarbonyl-Leu-Leu-Leu-B(OH)(2) (MG262) stabilize CYP3A proteins. However, MG132 has been reported to suppress P450s 3A as a result of impaired nuclear factor-kappaB activation and consequently reduced CYP3A protein stability. Because the MG132 concentration used in those studies was 10-fold higher than that required for CYP3A stabilization, we examined the effect of MG132 (0-300 microM) concentration-dependent proteasomal inhibition on CYP3A turnover in cultured primary rat hepatocytes. We found a biphasic MG132 concentration effect on CYP3A turnover: Stabilization at 5 to 10 muM with marked suppression at >100 microM. Proteasomal inhibitors reportedly induce ER stress, heat shock, and apoptotic response. At these high MG132 concentrations, such CYP3A suppression could be due to ER stress induction, so we monitored the activity of PERK [PKR (RNA-dependent protein kinase)-like ER kinase (EIF2AK3)], the ER stress-activated eukaryotic initiation factor 2alpha (eIF2alpha) kinase. Indeed, we found a marked (approximately 4-fold) MG132 concentration-dependent PERK autophosphorylation, along with an 8-fold increase in eIF2alpha-phosphorylation. In parallel, MG132 also activated GCN2 [general control nonderepressible-2 (EIF2AK4)] eIF2alpha kinase in a concentration-dependent manner, but not the heme-regulated inhibitor eIF2alpha kinase [(EIF2AK1)]. Pulse-chase, immunoprecipitation/immunoblotting analyses documented the consequently dramatic translational shutoff of total hepatic protein, including but not limited to CYP3A and tryptophan 2,3-dioxygenase protein syntheses. These findings reveal that at high concentrations, MG132 is indeed cytotoxic and can suppress CYP3A synthesis, a result confirmed by confocal immunofluorescence analyses of MG132-treated hepatocytes.
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Affiliation(s)
- Poulomi Acharya
- Dept. of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA
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20
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Tsai J, Zhang R, Qiu W, Su Q, Naples M, Adeli K. Inflammatory NF-kappaB activation promotes hepatic apolipoprotein B100 secretion: evidence for a link between hepatic inflammation and lipoprotein production. Am J Physiol Gastrointest Liver Physiol 2009; 296:G1287-98. [PMID: 19342510 DOI: 10.1152/ajpgi.90540.2008] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Insulin-resistant states are commonly associated with chronic inflammation and hepatic overproduction of apolipoprotein B100 (apoB100), leading to hypertriglyceridemia and a metabolic dyslipidemic profile. Molecular mechanisms linking hepatic inflammatory cascades and the pathways of apoB100-lipoprotein production are, however, unknown. In the present study, we employed a diet-induced, insulin-resistant hamster model, as well as cell culture studies, to investigate the potential link between activation of hepatic inflammatory nuclear factor-kappaB (NF-kappaB) signaling cascade and the synthesis and secretion of apoB100-containing lipoproteins. Using an established insulin-resistant animal model, the fructose-fed hamster, we found that feeding fructose (previously shown to induce hepatic inflammation) for as little as 4 days reduced hepatic IkappaB (inhibitor of NF-kappaB) level, indicating activation of the inflammatory NF-kappaB cascade. Importantly, IKK (IkappaB kinase) inhibition was found to suppress apoB100 overproduction in fructose-fed hamster hepatocytes. As IKK, the upstream activator of NF-kappaB has been shown to inhibit insulin signaling, and insulin is a major regulator of apoB100, we modulated IKK activity in primary hamster hepatocytes and HepG2 cells and assessed the effects on hepatic apoB100 biosynthesis. Inhibition of the IKK-NF-kappaB pathway by BMS345541 and activation of the pathway by adenoviral-mediated IKK overexpression decreased and increased newly synthesized apoB100 levels, respectively. Pulse-chase and metabolic labeling experiments revealed that IKK activation regulates apoB100 levels at the levels of apoB100 biosynthesis and protein stability. Inhibition of the IKK-NF-kappaB pathway significantly enhanced proteasomal degradation of hepatic apoB100, while direct IKK activation led to reduced degradation and increased apoB100 mRNA translation. Together, our results reveal important links between modulation of the inflammatory IKK-NF-kappaB signaling cascade and hepatic synthesis and secretion of apoB100-containing lipoproteins. Hepatic inflammation may be an important underlying factor in hepatic apoB100 overproduction observed in insulin resistance.
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Affiliation(s)
- Julie Tsai
- Department of Laboratory Medicine, University of Toronto, Canada
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21
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Medina-Díaz IM, Estrada-Muñiz E, Reyes-Hernández OD, Ramírez P, Vega L, Elizondo G. Arsenite and its metabolites, MMA(III) and DMA(III), modify CYP3A4, PXR and RXR alpha expression in the small intestine of CYP3A4 transgenic mice. Toxicol Appl Pharmacol 2008; 239:162-8. [PMID: 19084030 DOI: 10.1016/j.taap.2008.11.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Revised: 11/06/2008] [Accepted: 11/09/2008] [Indexed: 12/28/2022]
Abstract
Arsenic is an environmental pollutant that has been associated with an increased risk for the development of cancer and several other diseases through alterations of cellular homeostasis and hepatic function. Cytochrome P450 (P450) modification may be one of the factors contributing to these disorders. Several reports have established that exposure to arsenite modifies P450 expression by decreasing or increasing mRNA and protein levels. Cytochrome P450 3A4 (CYP3A4), the predominant P450 expressed in the human liver and intestines, which is regulated mainly by the Pregnane X Receptor-Retinoid X Receptor alpha (PXR-RXR alpha) heterodimer, contributes to the metabolism of approximately half the drugs in clinical use today. The present study investigates the effect of sodium arsenite and its metabolites monomethylarsonous acid (MMA(III)) and dimethylarsinous acid (DMA(III)) on CYP3A4, PXR, and RXR alpha expression in the small intestine of CYP3A4 transgenic mice. Sodium arsenite treatment increases mRNA, protein and CYP3A4 activity in a dose-dependent manner. However, the increase in protein expression was not as marked as compared to the increase in mRNA levels. Arsenite treatment induces the accumulation of Ub-protein conjugates, indicating that the activation of this mechanism may explain the differences observed between the mRNA and protein expression of CYP3A4 induction. Treatment with 0.05 mg/kg of DMA(III) induces CYP3A4 in a similar way, while treatment with 0.05 mg/kg of MMA(III) increases mostly mRNA, and to a lesser degree, CYP3A4 activity. Sodium arsenite and both its metabolites increase PXR mRNA, while only DMA(III) induces RXR alpha expression. Overall, these results suggest that sodium arsenite and its metabolites induce CYP3A4 expression by increasing PXR expression in the small intestine of CYP3A4 transgenic mice.
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Lu H, Chen CS, Waxman DJ. Potentiation of methoxymorpholinyl doxorubicin antitumor activity by P450 3A4 gene transfer. Cancer Gene Ther 2008; 16:393-404. [PMID: 19011599 DOI: 10.1038/cgt.2008.93] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Preclinical and clinical studies of CYP gene-directed enzyme prodrug therapy have been focused on anticancer prodrugs activated by CYP2B enzymes, which have low endogenous expression in human liver; however, the gene therapeutic potential of CYP3A enzymes, which are highly expressed in human liver, remains unknown. This study investigated methoxymorpholinyl doxorubicin (MMDX; nemorubicin), a novel CYP3A-activated anticancer prodrug. Retroviral transfer of CYP3A4 increased 9L gliosarcoma cell chemosensitivity to MMDX 120-fold (IC(50)=0.2 nM in 9L/3A4 cells). In CHO cells, overexpression of P450 reductase in combination with CYP3A4 enhanced chemosensitivity to MMDX, and to ifosfamide, another CYP3A4 prodrug, 11- to 23-fold compared with CYP3A4 expression alone. CYP3A4 expression and MMDX chemosensitivity were increased in human lung (A549) and brain (U251) tumor cells infected with replication-defective adenovirus encoding CYP3A4. Coinfection with Onyx-017, a replication-conditional adenovirus that coamplifies and coreplicates the Adeno-3A4 virus, led to large increases in CYP3A4 RNA but only modest increases in CYP3A4 protein and activity. MMDX induced remarkable growth delay of 9L/3A4 tumors, but not the P450-deficient parental 9L tumors, in immunodeficient mice administered low-dose MMDX either intravenous or by direct intratumoral (i.t.) injection (60 microg kg(-1), every 7 days x 3). Notably, the i.t. route was substantially less toxic to the mouse host. No antitumor activity was observed with intraperitoneal MMDX treatment, suggesting a substantial hepatic first pass effect, with activated MMDX metabolites formed in the liver having poor access to the tumor site. These studies demonstrate that human CYP3A4 has strong potential for MMDX prodrug-activation therapy and suggest that endogenous tumor cell expression of CYP3A4, and not hepatic CYP3A4 activity, is a key determinant of responsiveness to MMDX therapy in cancer patients in vivo.
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Affiliation(s)
- H Lu
- Department of Biology, Division of Cell and Molecular Biology, Boston University, Boston, MA 02215, USA
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