1
|
Qin M, Xin Y, Bian Y, Yang X, Xi T, Xiong J. Phosphorylation-Induced Ubiquitination and Degradation of PXR through CDK2-TRIM21 Axis. Cells 2022; 11:cells11020264. [PMID: 35053380 PMCID: PMC8773821 DOI: 10.3390/cells11020264] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 12/22/2021] [Accepted: 01/06/2022] [Indexed: 02/07/2023] Open
Abstract
Pregnane X receptor (PXR) is a member of the nuclear receptor superfamily that is activated by a variety of endogenous metabolites or xenobiotics. Its downstream target genes are involved in metabolism, inflammation and processes closely related to cancer. However, the stability regulation of PXR protein resulting from post-translational modification is still largely undefined. In the present study, primary mouse hepatocytes, hepatoma HepG2 cells and HEK 293T cells were used to investigate gene expression and protein interactions. The role of kinases was evaluated by RNA interference and overexpression constructs with or without PXR phosphorylation site mutations. The activity of CYP3A4 and P-gp was determined by enzymatic and substrate accumulation assays. It was found that E3 ubiquitin ligase TRIM21 mediates the ubiquitination and degradation of PXR and plays an important role in regulating the activity of PXR. On this basis, PXR phosphorylation-associated kinases were evaluated regarding regulation of the stability of PXR. We found cyclin dependent kinase 2 (CDK2) exclusively phosphorylates PXR at Ser350, promotes its disassociation with Hsp90/DNAJC7, and leads to subsequent TRIM21-mediated PXR ubiquitination and degradation. As well-known CDK inhibitors, dinaciclib and kenpaullone stabilize PXR and result in elevated expression and activity of PXR-targeted DMETs, including carboxylesterases, CYP3A4 and P-gp. The suppressed degradation of PXR by CDK2 inhibitors denotes dinaciclib-induced promotion of PXR-targeted genes. The findings of CDK2-mediated PXR degradation indicate a wide range of potential drug–drug interactions during clinical cancer therapy using CDK inhibitors and imply an alternative direction for the development of novel PXR antagonists.
Collapse
Affiliation(s)
- Mengyao Qin
- Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China; (M.Q.); (Y.X.); (X.Y.)
| | - Yu Xin
- Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China; (M.Q.); (Y.X.); (X.Y.)
| | - Yong Bian
- Laboratory Animal Center, Nanjing University of Chinese Medicine, Nanjing 210023, China;
| | - Xuan Yang
- Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China; (M.Q.); (Y.X.); (X.Y.)
| | - Tao Xi
- Research Center of Biotechnology, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China;
| | - Jing Xiong
- Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China; (M.Q.); (Y.X.); (X.Y.)
- Correspondence:
| |
Collapse
|
2
|
Niu X, Wu T, Li G, Gu X, Tian Y, Cui H. Insights into the critical role of the PXR in preventing carcinogenesis and chemotherapeutic drug resistance. Int J Biol Sci 2022; 18:742-759. [PMID: 35002522 PMCID: PMC8741843 DOI: 10.7150/ijbs.68724] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 11/21/2021] [Indexed: 12/12/2022] Open
Abstract
Pregnane x receptor (PXR) as a nuclear receptor is well-established in drug metabolism, however, it has pleiotropic functions in regulating inflammatory responses, glucose metabolism, and protects normal cells against carcinogenesis. Most studies focus on its transcriptional regulation, however, PXR can regulate gene expression at the translational level. Emerging evidences have shown that PXR has a broad protein-protein interaction network, by which is implicated in the cross signaling pathways. Furthermore, the interactions between PXR and some critical proteins (e.g., p53, Tip60, p300/CBP-associated factor) in DNA damage pathway highlight its potential roles in this field. A thorough understanding of how PXR maintains genome stability and prevents carcinogenesis will help clinical diagnosis and finally benefit patients. Meanwhile, due to the regulation of CYP450 enzymes CYP3A4 and multidrug resistance protein 1 (MDR1), PXR contributes to chemotherapeutic drug resistance. It is worthy of note that the co-factor of PXR such as RXRα, also has contributions to this process, which makes the PXR-mediated drug resistance more complicated. Although single nucleotide polymorphisms (SNPs) vary between individuals, the amino acid substitution on exon of PXR finally affects PXR transcriptional activity. In this review, we have summarized the updated mechanisms that PXR protects the human body against carcinogenesis, and major contributions of PXR with its co-factors have made on multidrug resistance. Furthermore, we have also reviewed the current promising antagonist and their clinic applications in reversing chemoresistance. We believe our review will bring insight into PXR-targeted cancer therapy, enlighten the future study direction, and provide substantial evidence for the clinic in future.
Collapse
Affiliation(s)
- Xiaxia Niu
- Institute of Toxicology, School of Public Health, Lanzhou University, 730000, Lanzhou, China
| | - Ting Wu
- Institute of Toxicology, School of Public Health, Lanzhou University, 730000, Lanzhou, China
| | - Gege Li
- Institute of Toxicology, School of Public Health, Lanzhou University, 730000, Lanzhou, China
| | - Xinsheng Gu
- Department of Pharmacology, College of Basic Medical Sciences, Hubei University of Medicine, Shiyan 442000, Hubei, China
| | - Yanan Tian
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, USA
| | - Hongmei Cui
- Institute of Toxicology, School of Public Health, Lanzhou University, 730000, Lanzhou, China
| |
Collapse
|
3
|
Liu M, Zhu D, Wen J, Ding W, Huang S, Xia C, Zhang H, Xiong Y. Berberine Promotes OATP1B1 Expression and Rosuvastatin Uptake by Inducing Nuclear Translocation of FXR and LXRα. Front Pharmacol 2020; 11:375. [PMID: 32292349 PMCID: PMC7118773 DOI: 10.3389/fphar.2020.00375] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Accepted: 03/12/2020] [Indexed: 12/19/2022] Open
Abstract
Berberine, a quinoline alkaloid, can be used in combination with statins to enhance hypolipidemic effects and reduce the dose and side effects of statins. The hypolipidemic effects of statins in the liver are mainly regulated by organic anion transporting polypeptides (OATPs), and the expression of OATPs is regulated by nuclear receptors. Berberine has been reported to affect nuclear receptors. However, whether berberine affects the uptake of statins by regulating nuclear receptor-mediated expression of OATPs remains to be determined. The aim of this study was to investigate the effects of berberine on the expression of OATP1B1 in HepG2 and explore the underlying mechanism. In HepG2 cells, 10-50 μM berberine significantly increased the uptake of rosuvastatin by inducing the expression of OATP1B1 mRNA and protein. Dual-Luciferase reporter assay showed that luciferase activity of hFXR and hLXRα activated OATP1B1 promoter was increased by 2.5-50 μM berberine in a concentration-dependent manner, with half-maximal effective concentration (EC50) of 12.19 ± 0.86 and 32.15 ± 2.32 μM, respectively. In addition, after silencing FXR or LXRα by small interfering RNA (siRNA), berberine-induced OATP1B1 expression was significantly attenuated. Western blot analysis of FXR and LXRα protein levels in the cytoplasm and nucleus of HepG2 cells after treatment with berberine showed that berberine induced nuclear translocation and activation of FXR and LXRα. In conclusion, berberine-induced nuclear translocation of FXR and LXRα could activate OATP1B1 promoter, resulting in enhanced expression of OATP1B1 and increased uptake of rosuvastatin.
Collapse
Affiliation(s)
- Mingyi Liu
- Clinical Pharmacology Institute, Nanchang University, Nanchang, China
| | - Dandan Zhu
- Clinical Pharmacology Institute, Nanchang University, Nanchang, China
| | - Jinhua Wen
- Department of Pharmacy, First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Wei Ding
- Clinical Pharmacology Institute, Nanchang University, Nanchang, China
| | - Shibo Huang
- Clinical Pharmacology Institute, Nanchang University, Nanchang, China
| | - Chunhua Xia
- Clinical Pharmacology Institute, Nanchang University, Nanchang, China
| | - Hong Zhang
- Clinical Pharmacology Institute, Nanchang University, Nanchang, China
| | - Yuqing Xiong
- Clinical Pharmacology Institute, Nanchang University, Nanchang, China
| |
Collapse
|
4
|
Wang Z, Liu Y, Ai X, Zhong L, Han G, Song J, Yang Q, Dong J. Effects of 27 natural products on drug metabolism genes in channel catfish (Ictalurus punctatus) cell line. Xenobiotica 2020; 50:1043-1051. [DOI: 10.1080/00498254.2020.1737760] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Zhenyue Wang
- Collage of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Yongtao Liu
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
- Key Laboratory of Control of Quality and Safety for Aquatic Products, Ministry of Agriculture and Rural Affairs, Beijing, China
- Hubei Province Engineering and Technology Research Center for Aquatic Product Quality and Safety, Wuhan, China
| | - Xiaohui Ai
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
- Key Laboratory of Control of Quality and Safety for Aquatic Products, Ministry of Agriculture and Rural Affairs, Beijing, China
- Hubei Province Engineering and Technology Research Center for Aquatic Product Quality and Safety, Wuhan, China
| | - Liqiao Zhong
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Gang Han
- Key Laboratory of Control of Quality and Safety for Aquatic Products, Ministry of Agriculture and Rural Affairs, Beijing, China
- Aquatic Products Quality and Standards Research Center, Chinese Academy of Fishery Sciences, Beijing, China
| | - Jinlong Song
- Key Laboratory of Control of Quality and Safety for Aquatic Products, Ministry of Agriculture and Rural Affairs, Beijing, China
- Aquatic Products Quality and Standards Research Center, Chinese Academy of Fishery Sciences, Beijing, China
| | - Qiuhong Yang
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| | - Jing Dong
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China
| |
Collapse
|
5
|
Ono K, Furugen A, Kurosawa Y, Jinno N, Narumi K, Kobayashi M, Iseki K. Analysis of the effects of polyunsaturated fatty acids on transporter expressions using a PCR array: Induction of xCT/SLC7A11 in human placental BeWo cells. Placenta 2018; 75:34-41. [PMID: 30712664 DOI: 10.1016/j.placenta.2018.11.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 11/04/2018] [Accepted: 11/26/2018] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Polyunsaturated fatty acids (PUFAs), including arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), are essential for adequate fetal growth. The aim of the present study was to elucidate the effects of PUFAs on the expression and function of placental transporters, which play important roles in placental functions including the supply of nutrients to the fetus, excretion of metabolites, and protection of the fetus from xenobiotics. METHODS Human placental choriocarcinoma BeWo cells were used as a trophoblast model. PUFA-induced alteration in the gene expression of 84 transporters was investigated by a commercially available PCR array. Protein levels and the activity of transporters were assessed by western blotting and uptake experiments, respectively. The placental expression of the transporters was analyzed using pregnant Wistar rats. RESULTS PUFAs (AA, EPA, and DHA) increased cystine/glutamate transporter xCT/SLC7A11, which mediates the cellular uptake of cystine coupled with the efflux of glutamate in human placental choriocarcinoma BeWo cells. These PUFAs also increased [14C]-cystine uptake in BeWo cells. PUFA-induced xCT/SLC7A11 mRNA expression was not blocked by nuclear factor-erythroid 2-related factor-2 (NRF2) knockdown. Reverse transcription (RT)-PCR analysis indicated that xCT/Slc7a11 mRNA was detected in rat placenta and the expression level at gestational day (GD) 12 was higher than that at GD 20. CONCLUSION These results indicate that PUFAs promoted cystine uptake in placental cells by inducing xCT/SLC7A11 expression and NRF2 did not contribute to upregulation of xCT/SLC7A11 by PUFAs. Furthermore, xCT expression in rat placenta may change during pregnancy.
Collapse
Affiliation(s)
- Kanako Ono
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12-jo, Nishi-6-chome, Kita-ku, Sapporo, 060-0812, Japan
| | - Ayako Furugen
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12-jo, Nishi-6-chome, Kita-ku, Sapporo, 060-0812, Japan
| | - Yuko Kurosawa
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12-jo, Nishi-6-chome, Kita-ku, Sapporo, 060-0812, Japan
| | - Naoko Jinno
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12-jo, Nishi-6-chome, Kita-ku, Sapporo, 060-0812, Japan
| | - Katsuya Narumi
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12-jo, Nishi-6-chome, Kita-ku, Sapporo, 060-0812, Japan
| | - Masaki Kobayashi
- Department of Pharmacy, Hokkaido University Hospital, Kita-14-jo, Nishi-5-chome, Kita-ku, Sapporo, 060-8648, Japan
| | - Ken Iseki
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12-jo, Nishi-6-chome, Kita-ku, Sapporo, 060-0812, Japan; Department of Pharmacy, Hokkaido University Hospital, Kita-14-jo, Nishi-5-chome, Kita-ku, Sapporo, 060-8648, Japan.
| |
Collapse
|
6
|
Yamasaki Y, Kobayashi K, Inaba A, Uehara D, Tojima H, Kakizaki S, Chiba K. Indirect activation of pregnane X receptor in the induction of hepatic CYP3A11 by high-dose rifampicin in mice. Xenobiotica 2017; 48:1098-1105. [PMID: 29095659 DOI: 10.1080/00498254.2017.1400128] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Rifampicin (RIF), a typical ligand of human pregnane X receptor (PXR), powerfully induces the expression of cytochrome P450 3A4 (CYP3A4) in humans. Although it is thought that RIF is not a ligand of rodent PXR, treatment with high-dose RIF (e.g. more than 20 mg/kg) increases the expression of CYP3A in the mouse liver. In this study, we investigated whether the induction of CYP3A by high-dose RIF in the mouse liver is mediated via indirect activation of mouse PXR (mPXR). The results showed that high-dose RIF increased the expression of CYP3A11 and other PXR-target genes in the liver of wild-type mice but not PXR-knockout mice. However, the results of reporter gene and ligand-dependent assembly assays showed that RIF does not activate mPXR in a ligand-dependent manner. In addition, high-dose RIF stimulated nuclear accumulation of mPXR in the mouse liver, and geldanamycin and okadaic acid attenuated the induction of Cyp3a11 and other PXR-target genes in primary hepatocytes, suggesting that high-dose RIF triggers nuclear translocation of mPXR. In conclusion, the present study suggests that high-dose RIF stimulates nuclear translocation of mPXR in the liver of mice by indirect activation, resulting in the transactivation of Cyp3a11 and other PXR-target genes.
Collapse
Affiliation(s)
- Yuki Yamasaki
- a Laboratory of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Chiba University , Chiba , Japan and
| | - Kaoru Kobayashi
- a Laboratory of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Chiba University , Chiba , Japan and
| | - Asumi Inaba
- a Laboratory of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Chiba University , Chiba , Japan and
| | - Daisuke Uehara
- b Division of Gastroenterology and Hepatology, Department of Internal Medicine, Graduate School of Medicine, Gunma University , Maebashi , Japan
| | - Hiroki Tojima
- b Division of Gastroenterology and Hepatology, Department of Internal Medicine, Graduate School of Medicine, Gunma University , Maebashi , Japan
| | - Satoru Kakizaki
- b Division of Gastroenterology and Hepatology, Department of Internal Medicine, Graduate School of Medicine, Gunma University , Maebashi , Japan
| | - Kan Chiba
- a Laboratory of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Chiba University , Chiba , Japan and
| |
Collapse
|
7
|
Yokobori K, Kobayashi K, Azuma I, Akita H, Chiba K. Intracellular localization of pregnane X receptor in HepG2 cells cultured by the hanging drop method. Drug Metab Pharmacokinet 2017; 32:265-272. [DOI: 10.1016/j.dmpk.2017.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Revised: 08/05/2017] [Accepted: 08/17/2017] [Indexed: 11/25/2022]
|
8
|
Nagarajan S, Vohra T, Loffing J, Faresse N. Protein Phosphatase 1α enhances renal aldosterone signaling via mineralocorticoid receptor stabilization. Mol Cell Endocrinol 2017; 450:74-82. [PMID: 28454724 DOI: 10.1016/j.mce.2017.04.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 04/18/2017] [Accepted: 04/22/2017] [Indexed: 01/21/2023]
Abstract
Stimulation of the mineralocorticoid receptor (MR) by aldosterone controls several physiological parameters including blood pressure, inflammation or metabolism. We previously showed that MR turnover constitutes a crucial regulatory step in the responses of renal epithelial cells to aldosterone. Here, we identified Protein Phosphatase 1 alpha (PP1α), as a novel cytoplasmic binding partner of MR that promotes the receptor activity. The RT-PCR expression mapping of PP1α reveals a high expression in the kidney, particularly in the distal part of the nephron. At the molecular level, we demonstrate that PP1α inhibits the ubiquitin ligase Mdm2 by dephosphorylation, preventing its interaction with MR. This results in the accumulation of the receptor due to reduction of its proteasomal degradation and consequently a greater aldosterone-induced Na+ uptake by renal cells. Thus, our findings describe an original mechanism involving a phosphatase in the regulation of aldosterone signaling and provide new and important insights into the molecular mechanism underlying the MR turnover.
Collapse
Affiliation(s)
- Shunmugam Nagarajan
- Institute of Anatomy, University of Zurich, 8057 Zurich, Switzerland; National Center of Competence in Research "Kidney.CH", Switzerland
| | - Twinkle Vohra
- Institute of Anatomy, University of Zurich, 8057 Zurich, Switzerland
| | - Johannes Loffing
- Institute of Anatomy, University of Zurich, 8057 Zurich, Switzerland; National Center of Competence in Research "Kidney.CH", Switzerland
| | - Nourdine Faresse
- Institute of Anatomy, University of Zurich, 8057 Zurich, Switzerland; National Center of Competence in Research "Kidney.CH", Switzerland.
| |
Collapse
|
9
|
Amacher DE. The regulation of human hepatic drug transporter expression by activation of xenobiotic-sensing nuclear receptors. Expert Opin Drug Metab Toxicol 2016; 12:1463-1477. [PMID: 27548410 DOI: 10.1080/17425255.2016.1223626] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
INTRODUCTION If a drug is found to be an inducer of hepatic drug metabolizing enzymes via activation of nuclear receptors such as pregnane X receptor (PXR) or constitutive androstane receptor (CAR), it is likely that drug transporters regulated through these same receptors will be induced as well. This review highlights what is currently known about the molecular mechanisms that regulate transporter expression and where the research is directed. Areas covered: This review is focused on publications that describe the role of activated hepatic nuclear receptors in the subsequent regulation of drug uptake and/or efflux transporters following exposure to xenobiotics. Expert opinion: Many of the published studies on the role of nuclear receptors in the regulation of drug transporters involve non-human test animals. But due to species response differences, these associations are not always applicable to humans. For this reason, some relevant human in vitro models have been developed, such as primary or cryopreserved human hepatocytes, human liver slices, or HepG2 or HuH7 cell lines transiently or stably transfected with PXR expression and reporter constructs as well as in vivo models such as PXR-humanized mice. These human-relevant test systems will continue to be developed and applied for the testing of investigational drugs.
Collapse
|
10
|
A SUMO-acetyl switch in PXR biology. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2016; 1859:1170-1182. [PMID: 26883953 DOI: 10.1016/j.bbagrm.2016.02.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 01/22/2016] [Accepted: 02/09/2016] [Indexed: 12/13/2022]
Abstract
Post-translational modification (PTM) of nuclear receptor superfamily members regulates various aspects of their biology to include sub-cellular localization, the repertoire of protein-binding partners, as well as their stability and mode of degradation. The nuclear receptor pregnane X receptor (PXR, NR1I2) is a master-regulator of the drug-inducible gene expression in liver and intestine. The PXR-mediated gene activation program is primarily recognized to increase drug metabolism, drug transport, and drug efflux pathways in these tissues. The activation of PXR also has important implications in significant human diseases including inflammatory bowel disease and cancer. Our recent investigations reveal that PXR is modified by multiple PTMs to include phosphorylation, SUMOylation, and ubiquitination. Using both primary cultures of hepatocytes and cell-based assays, we show here that PXR is modified through acetylation on lysine residues. Further, we show that increased acetylation of PXR stimulates its increased SUMO-modification to support active transcriptional suppression. Pharmacologic inhibition of lysine de-acetylation using trichostatin A (TSA) alters the sub-cellular localization of PXR in cultured hepatocytes, and also has a profound impact upon PXR transactivation capacity. Both the acetylation and SUMOylation status of the PXR protein is affected by its ability to associate with the lysine de-acetylating enzyme histone de-acetylase (HDAC)3 in a complex with silencing mediator of retinoic acid and thyroid hormone receptor (SMRT). Taken together, our data support a model in which a SUMO-acetyl 'switch' occurs such that acetylation of PXR likely stimulates SUMO-modification of PXR to promote the active repression of PXR-target gene expression. This article is part of a Special Issue entitled: Xenobiotic nuclear receptors: New Tricks for An Old Dog, edited by Dr. Wen Xie.
Collapse
|
11
|
Mackowiak B, Wang H. Mechanisms of xenobiotic receptor activation: Direct vs. indirect. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2016; 1859:1130-1140. [PMID: 26877237 DOI: 10.1016/j.bbagrm.2016.02.006] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 02/05/2016] [Accepted: 02/06/2016] [Indexed: 12/31/2022]
Abstract
The so-called xenobiotic receptors (XRs) have functionally evolved into cellular sensors for both endogenous and exogenous stimuli by regulating the transcription of genes encoding drug-metabolizing enzymes and transporters, as well as those involving energy homeostasis, cell proliferation, and/or immune responses. Unlike prototypical steroid hormone receptors, XRs are activated through both direct ligand-binding and ligand-independent (indirect) mechanisms by a plethora of structurally unrelated chemicals. This review covers research literature that discusses direct vs. indirect activation of XRs. A particular focus is centered on the signaling control of the constitutive androstane receptor (CAR), the pregnane X receptor (PXR), and the aryl hydrocarbon receptor (AhR). We expect that this review will shed light on both the common and distinct mechanisms associated with activation of these three XRs. This article is part of a Special Issue entitled: Xenobiotic nuclear receptors: New Tricks for An Old Dog, edited by Dr. Wen Xie.
Collapse
Affiliation(s)
- Bryan Mackowiak
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, MD 21201, United States
| | - Hongbing Wang
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, MD 21201, United States.
| |
Collapse
|
12
|
Cui W, Sun M, Galeva N, Williams TD, Azuma Y, Staudinger JL. SUMOylation and Ubiquitylation Circuitry Controls Pregnane X Receptor Biology in Hepatocytes. Drug Metab Dispos 2015; 43:1316-25. [PMID: 26063058 DOI: 10.1124/dmd.115.065201] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 06/10/2015] [Indexed: 12/25/2022] Open
Abstract
Several nuclear receptor (NR) superfamily members are known to be the molecular target of either the small ubiquitin-related modifier (SUMO) or ubiquitin-signaling pathways. However, little is currently known regarding how these two post-translational modifications interact to control NR biology. We show that SUMO and ubiquitin circuitry coordinately modifies the pregnane X receptor (PXR, NR1I2) to play a key role in regulating PXR protein stability, transactivation capacity, and transcriptional repression. The SUMOylation and ubiquitylation of PXR is increased in a ligand- and tumor necrosis factor alpha -: dependent manner in hepatocytes. The SUMO-E3 ligase enzymes protein inhibitor of activated signal transducer and activator of transcription-1 (STAT1) STAT-1 (PIAS1) and protein inhibitor of activated STAT Y (PIASy) drive high levels of PXR SUMOylation. Expression of protein inhibitor of activated stat 1 selectively increases SUMO(3)ylation as well as PXR-mediated induction of cytochrome P450, family 3, subfamily A and the xenobiotic response. The PIASy-mediated SUMO(1)ylation imparts a transcriptionally repressive function by ameliorating interaction of PXR with coactivator protein peroxisome proliferator-activated receptor gamma coactivator-1-alpha. The SUMO modification of PXR is effectively antagonized by the SUMO protease sentrin protease (SENP) 2, whereas SENP3 and SENP6 proteases are highly active in the removal of SUMO2/3 chains. The PIASy-mediated SUMO(1)ylation of PXR inhibits ubiquitin-mediated degradation of this important liver-enriched NR by the 26S proteasome. Our data reveal a working model that delineates the interactive role that these two post-translational modifications play in reconciling PXR-mediated gene activation of the xenobiotic response versus transcriptional repression of the proinflammatory response in hepatocytes. Taken together, our data reveal that the SUMOylation and ubiquitylation of the PXR interface in a fundamental manner directs its biologic function in the liver in response to xenobiotic or inflammatory stress.
Collapse
Affiliation(s)
- Wenqi Cui
- Departments of Pharmacology and Toxicology (W.C., J.L.S.), Mass Spectrometry Laboratory (N.G., T.D.W.), and Molecular Biosciences, University of Kansas, Lawrence, Kansas (Y.A.); and Department of Medicine, University of California, San Diego, La Jolla, California (M.S.)
| | - Mengxi Sun
- Departments of Pharmacology and Toxicology (W.C., J.L.S.), Mass Spectrometry Laboratory (N.G., T.D.W.), and Molecular Biosciences, University of Kansas, Lawrence, Kansas (Y.A.); and Department of Medicine, University of California, San Diego, La Jolla, California (M.S.)
| | - Nadezhda Galeva
- Departments of Pharmacology and Toxicology (W.C., J.L.S.), Mass Spectrometry Laboratory (N.G., T.D.W.), and Molecular Biosciences, University of Kansas, Lawrence, Kansas (Y.A.); and Department of Medicine, University of California, San Diego, La Jolla, California (M.S.)
| | - Todd D Williams
- Departments of Pharmacology and Toxicology (W.C., J.L.S.), Mass Spectrometry Laboratory (N.G., T.D.W.), and Molecular Biosciences, University of Kansas, Lawrence, Kansas (Y.A.); and Department of Medicine, University of California, San Diego, La Jolla, California (M.S.)
| | - Yoshiaki Azuma
- Departments of Pharmacology and Toxicology (W.C., J.L.S.), Mass Spectrometry Laboratory (N.G., T.D.W.), and Molecular Biosciences, University of Kansas, Lawrence, Kansas (Y.A.); and Department of Medicine, University of California, San Diego, La Jolla, California (M.S.)
| | - Jeff L Staudinger
- Departments of Pharmacology and Toxicology (W.C., J.L.S.), Mass Spectrometry Laboratory (N.G., T.D.W.), and Molecular Biosciences, University of Kansas, Lawrence, Kansas (Y.A.); and Department of Medicine, University of California, San Diego, La Jolla, California (M.S.)
| |
Collapse
|
13
|
Pondugula SR, Flannery PC, Apte U, Babu JR, Geetha T, Rege SD, Chen T, Abbott KL. Mg2+/Mn2+-dependent phosphatase 1A is involved in regulating pregnane X receptor-mediated cytochrome p450 3A4 gene expression. Drug Metab Dispos 2015; 43:385-91. [PMID: 25561723 PMCID: PMC11024896 DOI: 10.1124/dmd.114.062083] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 01/05/2015] [Indexed: 04/20/2024] Open
Abstract
Variations in the expression of human pregnane X receptor (hPXR)-mediated cytochrome p450 3A4 (CYP3A4) in liver can alter therapeutic response to a variety of drugs and may lead to potential adverse drug interactions. We sought to determine whether Mg(2+)/Mn(2+)-dependent phosphatase 1A (PPM1A) regulates hPXR-mediated CYP3A4 expression. PPM1A was found to be coimmunoprecipitated with hPXR. Genetic or pharmacologic activation of PPM1A led to a significant increase in hPXR transactivation of CYP3A4 promoter activity. In contrast, knockdown of endogenous PPM1A not only attenuated hPXR transactivation, but also increased proliferation of HepG2 human liver carcinoma cells, suggesting that PPM1A expression levels regulate hPXR, and that PPM1A expression is regulated in a proliferation-dependent manner. Indeed, PPM1A expression and hPXR transactivation were found to be significantly reduced in subconfluent HepG2 cells compared with confluent HepG2 cells, suggesting that both PPM1A expression and hPXR-mediated CYP3A4 expression may be downregulated in proliferating livers. Elevated PPM1A levels led to attenuation of hPXR inhibition by tumor necrosis factor-α and cyclin-dependent kinase-2, which are known to be upregulated and essential during liver regeneration. In mouse regenerating livers, similar to subconfluent HepG2 cells, expression of both PPM1A and the mouse PXR target gene cyp3a11 was found to be downregulated. Our results show that PPM1A can positively regulate PXR activity by counteracting PXR inhibitory signaling pathways that play a major role in liver regeneration. These results implicate a novel role for PPM1A in regulating hPXR-mediated CYP3A4 expression in hepatocytes and may explain a mechanism for CYP3A repression in regenerating livers.
Collapse
Affiliation(s)
- Satyanarayana R Pondugula
- Department of Anatomy, Physiology, and Pharmacology (S.R.P., P.C.F., K.L.A.) and Department of Nutrition, Dietetics, and Hospitality Management (J.R.B., S.D.R.), Auburn University, Auburn, Alabama; Department of Chemistry (T.G.), Auburn University at Montgomery, Montgomery, Alabama; Department of Chemical Biology and Therapeutics (T.C.), St. Jude Children's Research Hospital, Memphis, Tennessee; and Department of Pharmacology, Toxicology, and Therapeutics (U.A.), University of Kansas, Kansas City, Kansas
| | - Patrick C Flannery
- Department of Anatomy, Physiology, and Pharmacology (S.R.P., P.C.F., K.L.A.) and Department of Nutrition, Dietetics, and Hospitality Management (J.R.B., S.D.R.), Auburn University, Auburn, Alabama; Department of Chemistry (T.G.), Auburn University at Montgomery, Montgomery, Alabama; Department of Chemical Biology and Therapeutics (T.C.), St. Jude Children's Research Hospital, Memphis, Tennessee; and Department of Pharmacology, Toxicology, and Therapeutics (U.A.), University of Kansas, Kansas City, Kansas
| | - Udayan Apte
- Department of Anatomy, Physiology, and Pharmacology (S.R.P., P.C.F., K.L.A.) and Department of Nutrition, Dietetics, and Hospitality Management (J.R.B., S.D.R.), Auburn University, Auburn, Alabama; Department of Chemistry (T.G.), Auburn University at Montgomery, Montgomery, Alabama; Department of Chemical Biology and Therapeutics (T.C.), St. Jude Children's Research Hospital, Memphis, Tennessee; and Department of Pharmacology, Toxicology, and Therapeutics (U.A.), University of Kansas, Kansas City, Kansas
| | - Jeganathan Ramesh Babu
- Department of Anatomy, Physiology, and Pharmacology (S.R.P., P.C.F., K.L.A.) and Department of Nutrition, Dietetics, and Hospitality Management (J.R.B., S.D.R.), Auburn University, Auburn, Alabama; Department of Chemistry (T.G.), Auburn University at Montgomery, Montgomery, Alabama; Department of Chemical Biology and Therapeutics (T.C.), St. Jude Children's Research Hospital, Memphis, Tennessee; and Department of Pharmacology, Toxicology, and Therapeutics (U.A.), University of Kansas, Kansas City, Kansas
| | - Thangiah Geetha
- Department of Anatomy, Physiology, and Pharmacology (S.R.P., P.C.F., K.L.A.) and Department of Nutrition, Dietetics, and Hospitality Management (J.R.B., S.D.R.), Auburn University, Auburn, Alabama; Department of Chemistry (T.G.), Auburn University at Montgomery, Montgomery, Alabama; Department of Chemical Biology and Therapeutics (T.C.), St. Jude Children's Research Hospital, Memphis, Tennessee; and Department of Pharmacology, Toxicology, and Therapeutics (U.A.), University of Kansas, Kansas City, Kansas
| | - Shraddha D Rege
- Department of Anatomy, Physiology, and Pharmacology (S.R.P., P.C.F., K.L.A.) and Department of Nutrition, Dietetics, and Hospitality Management (J.R.B., S.D.R.), Auburn University, Auburn, Alabama; Department of Chemistry (T.G.), Auburn University at Montgomery, Montgomery, Alabama; Department of Chemical Biology and Therapeutics (T.C.), St. Jude Children's Research Hospital, Memphis, Tennessee; and Department of Pharmacology, Toxicology, and Therapeutics (U.A.), University of Kansas, Kansas City, Kansas
| | - Taosheng Chen
- Department of Anatomy, Physiology, and Pharmacology (S.R.P., P.C.F., K.L.A.) and Department of Nutrition, Dietetics, and Hospitality Management (J.R.B., S.D.R.), Auburn University, Auburn, Alabama; Department of Chemistry (T.G.), Auburn University at Montgomery, Montgomery, Alabama; Department of Chemical Biology and Therapeutics (T.C.), St. Jude Children's Research Hospital, Memphis, Tennessee; and Department of Pharmacology, Toxicology, and Therapeutics (U.A.), University of Kansas, Kansas City, Kansas
| | - Kodye L Abbott
- Department of Anatomy, Physiology, and Pharmacology (S.R.P., P.C.F., K.L.A.) and Department of Nutrition, Dietetics, and Hospitality Management (J.R.B., S.D.R.), Auburn University, Auburn, Alabama; Department of Chemistry (T.G.), Auburn University at Montgomery, Montgomery, Alabama; Department of Chemical Biology and Therapeutics (T.C.), St. Jude Children's Research Hospital, Memphis, Tennessee; and Department of Pharmacology, Toxicology, and Therapeutics (U.A.), University of Kansas, Kansas City, Kansas
| |
Collapse
|