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Kotulkar M, Paine-Cabrera D, Robarts DR, Apte U. Regulation of hepatic xenosensor function by HNF4alpha. Toxicol Sci 2024; 200:346-356. [PMID: 38810120 DOI: 10.1093/toxsci/kfae069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024] Open
Abstract
Nuclear receptors such as constitutive androstane receptor (CAR), pregnane X receptor (PXR), and peroxisome proliferator-activated receptor-alpha (PPARα), and transcription factors with nuclear receptor type activity such as aryl hydrocarbon receptor (AhR) function as xenobiotic sensors. Hepatocyte nuclear factor 4alpha (HNF4α) is a highly conserved orphan nuclear receptor essential for liver function. We tested the hypothesis that HNF4α is essential for the function of these 4 major xenosensors. Wild-type (WT) and hepatocyte-specific Hnf4a null (HNF4α-KO) mice were treated with the mouse-specific activators of AhR (TCDD, 30 µg/kg), CAR (TCPOBOP, 2.5 µg/g), PXR, (PCN, 100 µg/g), and PPARα (WY-14643, 1 mg/kg). Blood and liver tissue samples were collected to study receptor activation. TCDD (AhR agonist) treatment did not affect the liver-to-body weight ratio (LW/BW) in either WT or HNF4α-KO mice. Further, TCDD activated AhR in both WT and HNF4α-KO mice, confirmed by increase in expression of AhR target genes. TCPOBOP (CAR agonist) significantly increased the LW/BW ratio and CAR target gene expression in WT mice, but not in HNF4α-KO mice. PCN (a mouse PXR agonist) significantly increased LW/BW ratio in both WT and HNF4α-KO mice however, failed to induce PXR target genes in HNF4α-KO mice. The treatment of WY-14643 (PPARα agonist) increased LW/BW ratio and PPARα target gene expression in WT mice but not in HNF4α-KO mice. Together, these data indicate that the function of CAR, PXR, and PPARα but not of AhR was disrupted in HNF4α-KO mice. These results demonstrate that HNF4α function is critical for the activation of hepatic xenosensors, which are critical for toxicological responses.
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MESH Headings
- Animals
- Hepatocyte Nuclear Factor 4/metabolism
- Hepatocyte Nuclear Factor 4/genetics
- Liver/metabolism
- Liver/drug effects
- PPAR alpha/agonists
- PPAR alpha/metabolism
- PPAR alpha/genetics
- Mice, Knockout
- Constitutive Androstane Receptor
- Pregnane X Receptor/genetics
- Pregnane X Receptor/metabolism
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Cytoplasmic and Nuclear/agonists
- Receptors, Cytoplasmic and Nuclear/metabolism
- Mice
- Receptors, Steroid/genetics
- Receptors, Steroid/metabolism
- Receptors, Steroid/agonists
- Receptors, Aryl Hydrocarbon/agonists
- Receptors, Aryl Hydrocarbon/genetics
- Receptors, Aryl Hydrocarbon/metabolism
- Mice, Inbred C57BL
- Male
- Pyrimidines/pharmacology
- Polychlorinated Dibenzodioxins/toxicity
- Pyridines/pharmacology
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Affiliation(s)
- Manasi Kotulkar
- Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, United States
| | - Diego Paine-Cabrera
- Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, United States
| | - Dakota R Robarts
- Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, United States
| | - Udayan Apte
- Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, United States
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Rakateli L, Huchzermeier R, van der Vorst EPC. AhR, PXR and CAR: From Xenobiotic Receptors to Metabolic Sensors. Cells 2023; 12:2752. [PMID: 38067179 PMCID: PMC10705969 DOI: 10.3390/cells12232752] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 11/23/2023] [Accepted: 11/30/2023] [Indexed: 12/18/2023] Open
Abstract
Traditionally, xenobiotic receptors are known for their role in chemical sensing and detoxification, as receptor activation regulates the expression of various key enzymes and receptors. However, recent studies have highlighted that xenobiotic receptors also play a key role in the regulation of lipid metabolism and therefore function also as metabolic sensors. Since dyslipidemia is a major risk factor for various cardiometabolic diseases, like atherosclerosis and non-alcoholic fatty liver disease, it is of major importance to understand the molecular mechanisms that are regulated by xenobiotic receptors. In this review, three major xenobiotic receptors will be discussed, being the aryl hydrocarbon receptor (AhR), pregnane X receptor (PXR) and the constitutive androstane receptor (CAR). Specifically, this review will focus on recent insights into the metabolic functions of these receptors, especially in the field of lipid metabolism and the associated dyslipidemia.
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Affiliation(s)
- Leonida Rakateli
- Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, 52074 Aachen, Germany; (L.R.); (R.H.)
- Aachen-Maastricht Institute for CardioRenal Disease (AMICARE), RWTH Aachen University, 52074 Aachen, Germany
| | - Rosanna Huchzermeier
- Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, 52074 Aachen, Germany; (L.R.); (R.H.)
- Aachen-Maastricht Institute for CardioRenal Disease (AMICARE), RWTH Aachen University, 52074 Aachen, Germany
| | - Emiel P. C. van der Vorst
- Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, 52074 Aachen, Germany; (L.R.); (R.H.)
- Aachen-Maastricht Institute for CardioRenal Disease (AMICARE), RWTH Aachen University, 52074 Aachen, Germany
- Institute for Cardiovascular Prevention (IPEK), Ludwig-Maximilians-University Munich, 80336 Munich, Germany
- Interdisciplinary Center for Clinical Research (IZKF), RWTH Aachen University, 52074 Aachen, Germany
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Kotulkar M, Cabrera DP, Robarts D, Apte U. Regulation of Hepatic Xenosensor Function by HNF4alpha. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.11.561888. [PMID: 37873133 PMCID: PMC10592787 DOI: 10.1101/2023.10.11.561888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Nuclear receptors including Aryl hydrocarbon Receptor (AhR), Constitutive Androstane Receptor (CAR), Pregnane X Receptor (PXR), and Peroxisome Proliferator-Activated Receptor-alpha (PPARα) function as xenobiotic sensors. Hepatocyte nuclear factor 4alpha (HNF4α) is a highly conserved orphan nuclear receptor essential for liver function. We tested the hypothesis that HNF4α is essential for function of these four major xenosensors. Wild-type (WT) and hepatocyte-specific HNF4α knockout (HNF4α-KO) mice were treated with the mouse-specific activators of AhR (TCDD, 30 µg/kg), CAR (TCPOBOP, 2.5 µg/g), PXR, (PCN, 100 µg/g), and PPARα (WY-14643, 1 mg/kg). Blood and liver tissue samples were collected to study nuclear receptor activation. TCDD (AhR agonist) treatment did not affect the liver-to-body weight ratio (LW/BW) in either WT or HNF4α-KO mice. Further, TCDD activated AhR in both WT and HNF4-KO mice, confirmed by increase in expression of its target genes. TCPOBOP (CAR agonist) significantly increased the LW/BW ratio and CAR target gene expression in WT mice, but not in HNF4α-KO mice. PCN (a mouse PXR agonist) significantly increased LW/BW ratio in both WT and HNF4α-KO mice however, it failed to induce PXR target genes in HNF4 KO mice. The treatment of WY-14643 (PPARα agonist) increased LW/BW ratio and PPARα target gene expression in WT mice but not in HNF4α-KO mice. Together, these data indicate that the function of CAR, PXR, and PPARα but not of AhR was disrupted in HNF4α-KO mice. These results demonstrate that HNF4α function is critical for the activation of hepatic xenosensors, which are critical for toxicological responses.
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Wang J, Lu P, Xie W. Atypical functions of xenobiotic receptors in lipid and glucose metabolism. MEDICAL REVIEW (2021) 2022; 2:611-624. [PMID: 36785576 PMCID: PMC9912049 DOI: 10.1515/mr-2022-0032] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 11/08/2022] [Indexed: 12/02/2022]
Abstract
Xenobiotic receptors are traditionally defined as xenobiotic chemical-sensing receptors, the activation of which transcriptionally regulates the expression of enzymes and transporters involved in the metabolism and disposition of xenobiotics. Emerging evidence suggests that "xenobiotic receptors" also have diverse endobiotic functions, including their effects on lipid metabolism and energy metabolism. Dyslipidemia is a major risk factor for cardiovascular disease, diabetes, obesity, metabolic syndrome, stroke, nonalcoholic fatty liver disease (NAFLD), and nonalcoholic steatohepatitis (NASH). Understanding the molecular mechanism by which transcriptional factors, including the xenobiotic receptors, regulate lipid homeostasis will help to develop preventive and therapeutic approaches. This review describes recent advances in our understanding the atypical roles of three xenobiotic receptors: aryl hydrocarbon receptor (AhR), pregnane X receptor (PXR), and constitutive androstane receptor (CAR), in metabolic disorders, with a particular focus on their effects on lipid and glucose metabolism. Collectively, the literatures suggest the potential values of AhR, PXR and CAR as therapeutic targets for the treatment of NAFLD, NASH, obesity and diabetes, and cardiovascular diseases.
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Affiliation(s)
- Jingyuan Wang
- Center for Pharmacogenetics and Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Peipei Lu
- Center for Pharmacogenetics and Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Wen Xie
- Center for Pharmacogenetics and Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
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Liver regeneration after partial hepatectomy is improved in the absence of aryl hydrocarbon receptor. Sci Rep 2022; 12:15446. [PMID: 36104446 PMCID: PMC9474532 DOI: 10.1038/s41598-022-19733-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 09/02/2022] [Indexed: 11/19/2022] Open
Abstract
The liver is among the few organs having the ability to self-regenerate in response to a severe damage compromising its functionality. The Aryl hydrocarbon receptor (Ahr) is a transcription factor relevant for the detoxification of xenobiotics but also largely important for liver development and homeostasis. Hence, liver cell differentiation is developmentally modulated by Ahr through the controlled expression of pluripotency and stemness-inducing genes. Here, 2/3 partial hepatectomy (PH) was used as a clinically relevant approach to induce liver regeneration in Ahr-expressing (Ahr+/+) and Ahr-null (Ahr−/−) mice. Ahr expression and activity were early induced after 2/3 PH to be gradually downmodulated latter during regeneration. Ahr−/− mice triggered liver regeneration much faster than AhR+/+ animals, although both reached full regeneration at the latest times. At initial stages after PHx, earlier regenerating Ahr−/− livers had upregulation of cell proliferation markers and increased activation of signalling pathways related to stemness such as Hippo-YAP and Wnt/β-catenin, concomitantly with the induction of pro-inflammatory cytokines TNFa, IL6 and p65. These phenotypes, together with the improved metabolic adaptation of Ahr−/− mice after PHx and their induced sustained cell proliferation, could likely result from the expansion of undifferentiated stem cells residing in the liver expressing OCT4, SOX2, KLF4 and NANOG. We propose that Ahr needs to be induced early during regeneration to fine-tune liver regrowth to physiological values. Since Ahr deficiency did not result in liver overgrowth, its transient pharmacological inhibition could serve to improve liver regeneration in hepatectomized and transplanted patients and in those exposed to damaging liver toxins and carcinogens.
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Yoshinari K, Shizu R. Distinct Roles of the Sister Nuclear Receptors PXR and CAR in Liver Cancer Development. Drug Metab Dispos 2022; 50:1019-1026. [PMID: 35184041 DOI: 10.1124/dmd.121.000481] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 02/08/2022] [Indexed: 02/13/2025] Open
Abstract
Pregnane X receptor (PXR) and constitutively active receptor/constitutive androstane receptor (CAR) are xenobiotic-responsible transcription factors belonging to the same nuclear receptor gene subfamily and highly expressed in the liver. These receptors are activated by a variety of chemicals and play pivotal roles in many liver functions, including xenobiotic metabolism and disposition. Phenobarbital, an enzyme inducer and liver tumor promoter, activates both rodent and human CAR but causes liver tumors only in rodents. Although the precise mechanism for phenobarbital/CAR-mediated liver tumor formation remains to be established, intracellular pathways, including the Hippo pathway/Yes-associated protein-TEA-domain family members system and β-catenin signaling, seem to be involved. In contrast to CAR, previous findings by our group suggest that PXR activation does not promote hepatocyte proliferation but it enhances the proliferation induced by various stimuli. Moreover, and surprisingly, PXR may have antitumor effects in both rodents and humans by targeting inflammatory cytokine signals, angiogenesis and epithelial-mesenchymal transition. In this review, we summarize the current knowledge on the associations of PXR and CAR with hepatocyte proliferation and liver tumorigenesis and their molecular mechanisms and species differences. SIGNIFICANCE STATEMENT: Pregnane X receptor and constitutively active receptor/constitutive androstane receptor have very similar functions in the gene regulation associated with xenobiotic disposition, as suggested by their identification as xenosensors for enzyme induction. In contrast, recent reports clearly suggest that these receptors play distinct roles in the control of hepatocyte proliferation and liver cancer development. Understanding these differences at the molecular level may help us evaluate the human safety of chemical compounds and develop novel drugs targeting liver cancers.
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Affiliation(s)
- Kouichi Yoshinari
- Laboratory of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
| | - Ryota Shizu
- Laboratory of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
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Targeting Nuclear Receptors in Lung Cancer—Novel Therapeutic Prospects. Pharmaceuticals (Basel) 2022; 15:ph15050624. [PMID: 35631448 PMCID: PMC9145966 DOI: 10.3390/ph15050624] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/10/2022] [Accepted: 05/13/2022] [Indexed: 01/27/2023] Open
Abstract
Lung cancer, the second most commonly diagnosed cancer, is the major cause of fatalities worldwide for both men and women, with an estimated 2.2 million new incidences and 1.8 million deaths, according to GLOBOCAN 2020. Although various risk factors for lung cancer pathogenesis have been reported, controlling smoking alone has a significant value as a preventive measure. In spite of decades of extensive research, mechanistic cues and targets need to be profoundly explored to develop potential diagnostics, treatments, and reliable therapies for this disease. Nuclear receptors (NRs) function as transcription factors that control diverse biological processes such as cell growth, differentiation, development, and metabolism. The aberrant expression of NRs has been involved in a variety of disorders, including cancer. Deregulation of distinct NRs in lung cancer has been associated with numerous events, including mutations, epigenetic modifications, and different signaling cascades. Substantial efforts have been made to develop several small molecules as agonists or antagonists directed to target specific NRs for inhibiting tumor cell growth, migration, and invasion and inducing apoptosis in lung cancer, which makes NRs promising candidates for reliable lung cancer therapeutics. The current work focuses on the importance of various NRs in the development and progression of lung cancer and highlights the different small molecules (e.g., agonist or antagonist) that influence NR expression, with the goal of establishing them as viable therapeutics to combat lung cancer.
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Zhao P, Fan S, Gao Y, Huang M, Bi H. Nuclear Receptor-Mediated Hepatomegaly and Liver Regeneration: An Update. Drug Metab Dispos 2022; 50:636-645. [PMID: 35078806 DOI: 10.1124/dmd.121.000454] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 01/04/2022] [Indexed: 02/13/2025] Open
Abstract
Nuclear receptors (NRs), a superfamily of ligand-activated transcription factors, are critical in cell growth, proliferation, differentiation, metabolism, and numerous biologic events. NRs have been reported to play important roles in hepatomegaly (liver enlargement) and liver regeneration by regulating target genes or interacting with other signals. In this review, the roles and involved molecular mechanisms of NRs in hepatomegaly and liver regeneration are summarized and the future perspectives of NRs in the treatment of liver diseases are discussed. SIGNIFICANCE STATEMENT: NRs play critical roles in hepatomegaly and liver regeneration, indicating the potential of NRs as targets to promote liver repair after liver injury. This paper reviews the characteristics and molecular mechanisms of NRs in regulating hepatomegaly and liver regeneration, providing more evidence for NRs in the treatment of related liver diseases.
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Affiliation(s)
- Pengfei Zhao
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China (P.Z., S.F., Y.G., M.H., H.B.); and NMPA Key Laboratory for Research and Evaluation of Drug Metabolism, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China (H.B.)
| | - Shicheng Fan
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China (P.Z., S.F., Y.G., M.H., H.B.); and NMPA Key Laboratory for Research and Evaluation of Drug Metabolism, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China (H.B.)
| | - Yue Gao
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China (P.Z., S.F., Y.G., M.H., H.B.); and NMPA Key Laboratory for Research and Evaluation of Drug Metabolism, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China (H.B.)
| | - Min Huang
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China (P.Z., S.F., Y.G., M.H., H.B.); and NMPA Key Laboratory for Research and Evaluation of Drug Metabolism, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China (H.B.)
| | - Huichang Bi
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China (P.Z., S.F., Y.G., M.H., H.B.); and NMPA Key Laboratory for Research and Evaluation of Drug Metabolism, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China (H.B.)
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Natural product-based screening led to the discovery of a novel PXR agonist with anti-cholestasis activity. Acta Pharmacol Sin 2021; 43:2139-2146. [PMID: 34931017 PMCID: PMC9343401 DOI: 10.1038/s41401-021-00793-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 10/11/2021] [Indexed: 12/15/2022]
Abstract
Cholestasis is a major cause of a series of bile flow malfunction-related liver diseases. Pregnane X receptor (PXR) is a key regulator in endo- and xeno-biotics metabolism, which has been considered as a promising therapeutic target for cholestasis. In this study we conducted human PXR (hPXR) agonistic screening using dual-luciferase reporter gene assays, which led to discovering a series of potent hPXR agonists from a small Euphorbiaceae diterpenoid library, containing 35 structurally diverse diterpenoids with eight different skeleton types. The most active compound 6, a lathyrane diterpenoid (5/11/3 ring system), dose-dependently activated hPXR with a high selectivity, and significantly upregulated the expression of hPXR downstream genes CYP3A4 and UGT1A1. In LCA-induced cholestasis mouse model, administration of compound 6 (50 mg· kg-1. d-1, ip) for 7 days significantly suppressed liver necrosis and decreased serum levels of AST, ALT, Tbili, ALP, and TBA, ameliorating LCA-induced cholestatic liver injury. We further revealed that compound 6 exerted its anti-cholestatic efficacy via activation of PXR pathway, accelerating the detoxification of toxic BAs and promoting liver regeneration. These results suggest that lathyrane diterpenoids may serve as a promising scaffold for future development of anti-cholestasis drugs.
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High Pregnane X Receptor (PXR) Expression Is Correlated with Poor Prognosis in Invasive Breast Carcinoma. Diagnostics (Basel) 2021; 11:diagnostics11111946. [PMID: 34829293 PMCID: PMC8624096 DOI: 10.3390/diagnostics11111946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 10/12/2021] [Accepted: 10/15/2021] [Indexed: 11/16/2022] Open
Abstract
Pregnane X Receptor (PXR) is involved in human cancer, either by directly affecting carcinogenesis or by inducing drug-drug interactions and chemotherapy resistance. The clinical significance of PXR expression in invasive breast carcinoma was evaluated in the present study. PXR protein expression was assessed immunohistochemically on formalin fixed paraffin-embedded breast invasive carcinoma tissue sections, obtained from 148 patients, and was correlated with clinicopathological parameters, molecular phenotypes, tumor cells' proliferative capacity, and overall disease-free patients' survival. Additionally, the expression of PXR was examined on human breast carcinoma cell lines of different histological grade, hormonal status, and metastatic potential. PXR positivity was noted in 79 (53.4%) and high PXR expression in 48 (32.4%), out of 148 breast carcinoma cases. High PXR expression was positively associated with nuclear grade (p = 0.0112) and histological grade of differentiation (p = 0.0305), as well as with tumor cells' proliferative capacity (p = 0.0051), and negatively with luminal A subtype (p = 0.0295). Associations between high PXR expression, estrogen, and progesterone receptor negative status were also recorded (p = 0.0314 and p = 0.0208, respectively). High PXR expression was associated with shorter overall patients' survival times (log-rank test, p = 0.0009). In multivariate analysis, high PXR expression was identified as an independent prognostic factor of overall patients' survival (Cox-regression analysis, p = 0.0082). PXR expression alterations were also noted in breast cancer cell lines of different hormonal status. The present data supported evidence that PXR was related to a more aggressive invasive breast carcinoma phenotype, being a strong and independent poor prognosticator.
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Jiang H, Garcia V, Yanum JA, Lee J, Dai G. Circadian clock core component Bmal1 dictates cell cycle rhythm of proliferating hepatocytes during liver regeneration. Am J Physiol Gastrointest Liver Physiol 2021; 321:G389-G399. [PMID: 34431407 PMCID: PMC8560370 DOI: 10.1152/ajpgi.00204.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 08/05/2021] [Accepted: 08/13/2021] [Indexed: 02/06/2023]
Abstract
After partial hepatectomy (PH), the majority of remnant hepatocytes synchronously enter and rhythmically progress through the cell cycle for three major rounds to regain lost liver mass. Whether and how the circadian clock core component Bmal1 modulates this process remains elusive. We performed PH on Bmal1+/+ and hepatocyte-specific Bmal1 knockout (Bmal1hep-/-) mice and compared the initiation and progression of the hepatocyte cell cycle. After PH, Bmal1+/+ hepatocytes exhibited three major waves of nuclear DNA synthesis. In contrast, in Bmal1hep-/- hepatocytes, the first wave of nuclear DNA synthesis was delayed by 12 h, and the third such wave was lost. Following PH, Bmal1+/+ hepatocytes underwent three major waves of mitosis, whereas Bmal1hep-/- hepatocytes fully abolished mitotic oscillation. These Bmal1-dependent disruptions in the rhythmicity of hepatocyte cell cycle after PH were accompanied by suppressed expression peaks of a group of cell cycle components and regulators and dysregulated activation patterns of mitogenic signaling molecules c-Met and epidermal growth factor receptor. Moreover, Bmal1+/+ hepatocytes rhythmically accumulated fat as they expanded following PH, whereas this phenomenon was largely inhibited in Bmal1hep-/- hepatocytes. In addition, during late stages of liver regrowth, Bmal1 absence in hepatocytes caused the activation of redox sensor Nrf2, suggesting an oxidative stress state in regenerated liver tissue. Collectively, we demonstrated that during liver regeneration, Bmal1 partially modulates the oscillation of S-phase progression, fully controls the rhythmicity of M-phase advancement, and largely governs fluctuations in fat metabolism in replicating hepatocytes, as well as eventually determines the redox state of regenerated livers.NEW & NOTEWORTHY We demonstrated that Bmal1 centrally controls the synchronicity and rhythmicity of the cell cycle and lipid accumulation in replicating hepatocytes during liver regeneration. Bmal1 plays these roles, at least in part, by ensuring formation of the expression peaks of cell cycle components and regulators, as well as the timing and levels of activation of mitogenic signaling molecules.
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Affiliation(s)
- Huaizhou Jiang
- School of Traditional Chinese Medicine, Anhui University of Chinese Medicine, Hefei, China
- Department of Biology, School of Science, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana
| | - Veronica Garcia
- Department of Biology, School of Science, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana
| | - Jennifer Abla Yanum
- Department of Biology, School of Science, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana
| | - Joonyong Lee
- Department of Biology, School of Science, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana
| | - Guoli Dai
- Department of Biology, School of Science, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana
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Sultana H, Komai M, Shirakawa H. The Role of Vitamin K in Cholestatic Liver Disease. Nutrients 2021; 13:nu13082515. [PMID: 34444675 PMCID: PMC8400302 DOI: 10.3390/nu13082515] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/14/2021] [Accepted: 07/21/2021] [Indexed: 12/13/2022] Open
Abstract
Vitamin K (VK) is a ligand of the pregnane X receptor (PXR), which plays a critical role in the detoxification of xenobiotics and metabolism of bile acids. VK1 may reduce the risk of death in patients with chronic liver failure. VK deficiency is associated with intrahepatic cholestasis, and is already being used as a drug for cholestasis-induced liver fibrosis in China. In Japan, to treat osteoporosis in patients with primary biliary cholangitis, VK2 formulations are prescribed, along with vitamin D3. Animal studies have revealed that after bile duct ligation-induced cholestasis, PXR knockout mice manifested more hepatic damage than wild-type mice. Ligand-mediated activation of PXR improves biochemical parameters. Rifampicin is a well-known human PXR ligand that has been used to treat intractable pruritus in severe cholestasis. In addition to its anti-cholestatic properties, PXR has anti-fibrotic and anti-inflammatory effects. However, because of the scarcity of animal studies, the mechanism of the effect of VK on cholestasis-related liver disease has not yet been revealed. Moreover, the application of VK in cholestasis-related diseases is controversial. Considering this background, the present review focuses on the effect of VK in cholestasis-related diseases, emphasizing its function as a modulator of PXR.
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Affiliation(s)
- Halima Sultana
- Laboratory of Nutrition, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-8572, Japan; (H.S.); (M.K.)
| | - Michio Komai
- Laboratory of Nutrition, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-8572, Japan; (H.S.); (M.K.)
| | - Hitoshi Shirakawa
- Laboratory of Nutrition, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-8572, Japan; (H.S.); (M.K.)
- International Education and Research Center for Food Agricultural Immunology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-8572, Japan
- Correspondence: ; Tel.: +81-22-757-4402
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Zhao YY, Yao XP, Jiao TY, Tian JN, Gao Y, Fan SC, Chen PP, Jiang YM, Zhou YY, Chen YX, Yang X, Huang M, Bi HC. Schisandrol B promotes liver enlargement via activation of PXR and YAP pathways in mice. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2021; 84:153520. [PMID: 33662920 DOI: 10.1016/j.phymed.2021.153520] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 01/28/2021] [Accepted: 02/15/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Schisandrol B (SolB) is one of the bioactive components from a traditional Chinese medicine Schisandra chinensis or Schisandra sphenanthera. It has been demonstrated that SolB exerts hepatoprotective effects against drug-induced liver injury and promotes liver regeneration. It was found that SolB can induce hepatomegaly but the involved mechanisms remain unknown. PURPOSE This study aimed to explore the mechanisms involved in SolB-induced hepatomegaly. METHODS Male C57BL/6 mice were injected intraperitoneally with SolB (100 mg/kg) for 5 days. Serum and liver samples were collected for biochemical and histological analyses. The mechanisms of SolB were investigated by qRT-PCR and western blot analyses, luciferase reporter gene assays and immunofluorescence. RESULTS SolB significantly increased hepatocyte size and proliferation, and then promoted liver enlargement without liver injury and inflammation. SolB transactivated human PXR, activated PXR in mice and upregulated hepatic expression of its downstream proteins, such as CYP3A11, CYP2B10 and UGT1A1. SolB also significantly enhanced nuclear translocation of PXR and YAP in human cell lines. YAP signal pathway was activated by SolB in mice. CONCLUSION These findings demonstrated that SolB can significantly induce liver enlargement, which is associated with the activation of PXR and YAP pathways.
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Affiliation(s)
- Ying-Yuan Zhao
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Xin-Peng Yao
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Ting-Ying Jiao
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Jia-Ning Tian
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Yue Gao
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Shi-Cheng Fan
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Pan-Pan Chen
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Yi-Ming Jiang
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Yan-Ying Zhou
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Yi-Xin Chen
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Xiao Yang
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Min Huang
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Hui-Chang Bi
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China; School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China.
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Shizu R, Ishimura M, Nobusawa S, Hosaka T, Sasaki T, Kakizaki S, Yoshinari K. The influence of the long-term chemical activation of the nuclear receptor pregnane X receptor (PXR) on liver carcinogenesis in mice. Arch Toxicol 2021; 95:1089-1102. [PMID: 33398415 DOI: 10.1007/s00204-020-02955-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 11/12/2020] [Indexed: 12/13/2022]
Abstract
Pregnane X receptor (PXR) and constitutive androstane receptor (CAR) are nuclear receptors that are highly expressed in the liver and activated by numerous chemicals. While CAR activation by its activators, such as phenobarbital (PB), induces hepatocyte proliferation and liver carcinogenesis in rodents, it remains unclear whether PXR activation drives liver cancer. To investigate the influence of PXR activation on liver carcinogenesis, we treated mice with the PXR activator pregnenolone 16α-carbonitrile (PCN) with or without PB following tumor initiation with diethylnitrosamine (DEN). After 20 weeks of treatment, preneoplastic lesions detected by immunostaining with an anti-KRT8/18 antibody were observed in PB-treated but not PCN-treated mice, and PCN cotreatment augmented the formation of preneoplastic lesions by PB. After 35 weeks of treatment, macroscopic observations indicated that PB-treated and PB/PCN-cotreated mice had increased numbers of liver tumors compared to control and PCN-treated mice. In the pathological analyses of liver sections, all the mice in the PB and PB/PCN groups developed carcinoma and/or eosinophilic adenoma, but in the PB/PCN group, the multiplicity of carcinoma and eosinophilic adenoma was significantly reduced and the size of carcinoma showed a tendency to decrease. No mouse in the control or PCN-treated group developed such tumors. Differentially expressed gene (DEG) and gene set enrichment analyses in combination with RNA sequencing suggested the increased expression of genes related to epithelial-mesenchymal transition (EMT) in mice cotreated with PCN and PB compared to those treated with PB alone. Changes in the hepatic mRNA levels of epithelial marker genes supported the results of the transcriptome analyses. In conclusion, the present results suggest that PXR activation does not promote hepatocarcinogenesis in contrast to CAR and rather attenuates CAR-mediated liver cancer development by suppressing the EMT of liver cancer cells in rodents.
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Affiliation(s)
- Ryota Shizu
- Laboratory of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan
| | - Mai Ishimura
- Laboratory of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan
| | - Sumihito Nobusawa
- Department of Human Pathology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Takuomi Hosaka
- Laboratory of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan
| | - Takamitsu Sasaki
- Laboratory of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan
| | - Satoru Kakizaki
- Department of Gastroenterology and Hepatology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Kouichi Yoshinari
- Laboratory of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan.
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Cai X, Young GM, Xie W. The xenobiotic receptors PXR and CAR in liver physiology, an update. Biochim Biophys Acta Mol Basis Dis 2021; 1867:166101. [PMID: 33600998 DOI: 10.1016/j.bbadis.2021.166101] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 01/25/2021] [Accepted: 02/06/2021] [Indexed: 12/18/2022]
Abstract
Pregnane X receptor (PXR) and constitutive androstane receptor (CAR) are two nuclear receptors that are well-known for their roles in xenobiotic detoxification by regulating the expression of drug-metabolizing enzymes and transporters. In addition to metabolizing drugs and other xenobiotics, the same enzymes and transporters are also responsible for the production and elimination of numerous endogenous chemicals, or endobiotics. Moreover, both PXR and CAR are highly expressed in the liver. As such, it is conceivable that PXR and CAR have major potentials to affect the pathophysiology of the liver by regulating the homeostasis of endobiotics. In recent years, the physiological functions of PXR and CAR in the liver have been extensively studied. Emerging evidence has suggested the roles of PXR and CAR in energy metabolism, bile acid homeostasis, cell proliferation, to name a few. This review summarizes the recent progress in our understanding of the roles of PXR and CAR in liver physiology.
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Affiliation(s)
- Xinran Cai
- Center for Pharmacogenetics, Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Gregory M Young
- Center for Pharmacogenetics, Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Wen Xie
- Center for Pharmacogenetics, Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA 15261, USA; Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA.
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Zhang X, Xu Y, Bai Q, Li X, Han J, Hou Y, Ji Y, Zhang Z. Inhibition of LXR signaling by SULT2B1b promotes liver regeneration after partial hepatectomy in mouse models of nonalcoholic fatty liver disease. Am J Physiol Gastrointest Liver Physiol 2020; 319:G87-G96. [PMID: 32475129 DOI: 10.1152/ajpgi.00380.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Hydroxysteroid sulfotransferase 2B1b (SULT2B1b) plays a critical role in hepatic energy homeostasis. Liver X receptors (LXRs) are implicated in multiple physiological functions, including the inhibition of hepatocyte proliferation and regulation of fatty acid and cholesterol metabolism. We have previously reported that SULT2B1b promotes hepatocyte proliferation by inactivating LXR signaling in vivo and in vitro, leading to our hypothesis that SULT2B1b promotes fatty liver regeneration. In the present study, female C57BL/6 and S129 mice were fed a high-fat diet for 8 wk to establish a nonalcoholic fatty liver disease (NAFLD) mouse model. 70% partial hepatectomy (PH) was performed to induce liver regeneration. Our experiments revealed that the SULT2B1b overexpression significantly promotes the regeneration of hepatocytes in NAFLD C57BL/6 mice after PH, increasing liver regrowth by 11% within 1 day, and then by 21%, 33%, and 24% by 2, 3, and 5 days post-PH, respectively. Compared with the wild-type NAFLD S129 mice, SULT2B1 deletion NAFLD S129 mice presented reduced hepatocyte regeneration at postoperative day 2, as verified by decreased liver regrowth (37.4% vs. 46.1%, P < 0.05) and the results of immunohistochemical staining, quantitative real-time polymerase chain reaction, and Western blot analysis. Moreover, LXRα signaling and SULT2B1b expression are highly correlated in the regeneration of NAFLD mouse liver; SULT2B1b overexpression suppresses LXRα signaling, while the LXRα-signaling agonist T0901317 blocks SULT2B1b-induced hepatocyte regeneration in NAFLD mouse liver. Thus, the upregulation of SULT2B1b may promote hepatocyte regeneration via the suppression of LXRα activation in NAFLD mice, providing a potential strategy for improving hepatic-steatosis-related liver regeneration disorders.NEW & NOTEWORTHY This study demonstrates for the first time that hydroxysteroid sulfotransferase 2B1b (SULT2B1b) overexpression promotes the regeneration of fatty liver after partial hepatectomy in mice with nonalcoholic fatty liver disease, while reducing triglyceride accumulation in the regenerative fatty liver. Liver X receptor signaling may be crucial in the SULT2B1b-mediated regeneration of fatty liver. Thus, SULT2B1b may be a potential target for treating hepatic steatosis-related liver regeneration disorders.
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Affiliation(s)
- Xin Zhang
- Department of Pathology, Fudan University Zhongshan Hospital, Shanghai, China
| | - Yuyin Xu
- Department of Pathology, Fudan University Shanghai Cancer Centre, Shanghai, China.,Department of Pathology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Qianming Bai
- Department of Pathology, Fudan University Shanghai Cancer Centre, Shanghai, China
| | - Xiaobo Li
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Jing Han
- Department of Pathology, Fudan University Zhongshan Hospital, Shanghai, China
| | - Yingyong Hou
- Department of Pathology, Fudan University Zhongshan Hospital, Shanghai, China
| | - Yuan Ji
- Department of Pathology, Fudan University Zhongshan Hospital, Shanghai, China
| | - Zhigang Zhang
- Department of Pathology, School of Basic Medical Sciences, Fudan University, Shanghai, China
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Lee J, Garcia V, Nambiar SM, Jiang H, Dai G. Pregnancy facilitates maternal liver regeneration after partial hepatectomy. Am J Physiol Gastrointest Liver Physiol 2020; 318:G772-G780. [PMID: 32003603 PMCID: PMC7191459 DOI: 10.1152/ajpgi.00125.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Liver resection induces robust liver regrowth or regeneration to compensate for the lost tissue mass. In a clinical setting, pregnant women may need liver resection without terminating pregnancy in some cases. However, how pregnancy affects maternal liver regeneration remains elusive. We performed 70% partial hepatectomy (PH) in nonpregnant mice and gestation day 14 mice, and histologically and molecularly compared their liver regrowth during the next 4 days. We found that compared with the nonpregnant state, pregnancy altered the molecular programs driving hepatocyte replication, indicated by enhanced activities of epidermal growth factor receptor and STAT5A, reduced activities of cMet and p70S6K, decreased production of IL-6, TNFα, and hepatocyte growth factor, suppressed cyclin D1 expression, increased cyclin A1 expression, and early activated cyclin A2 expression. As a result, pregnancy allowed the remnant hepatocytes to enter the cell cycle at least 12 h earlier, increased hepatic fat accumulation, and enhanced hepatocyte mitosis. Consequently, pregnancy ameliorated maternal liver regeneration following PH. In addition, a report showed that maternal liver regrowth after PH is driven mainly by hepatocyte hypertrophy rather than hyperplasia during the second half of gestation in young adult mice. In contrast, we demonstrate that maternal liver relies mainly on hepatocyte hyperplasia instead of hypertrophy to restore the lost mass after PH. Overall, we demonstrate that pregnancy facilitates maternal liver regeneration likely via triggering an early onset of hepatocyte replication, accumulating excessive liver fat, and promoting hepatocyte mitosis. The results from our current studies enable us to gain more insights into how maternal liver regeneration progresses during gestation.NEW & NOTEWORTHY We demonstrate that pregnancy may generate positive effects on maternal liver regeneration following partial hepatectomy, which are manifested by early entry of the cell cycle of remnant hepatocytes, increased hepatic fat accumulation, enhanced hepatocyte mitosis, and overall accelerated liver regrowth.
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Affiliation(s)
- Joonyong Lee
- 1Department of Biology, Center for Developmental and Regenerative Biology, School of Science, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana
| | - Veronica Garcia
- 1Department of Biology, Center for Developmental and Regenerative Biology, School of Science, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana
| | - Shashank Manohar Nambiar
- 1Department of Biology, Center for Developmental and Regenerative Biology, School of Science, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana
| | - Huaizhou Jiang
- 1Department of Biology, Center for Developmental and Regenerative Biology, School of Science, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana,2School of Traditional Chinese Medicine, Anhui University of Chinese Medicine, Anhui, China
| | - Guoli Dai
- 1Department of Biology, Center for Developmental and Regenerative Biology, School of Science, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana
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Shizu R, Yoshinari K. Nuclear receptor CAR-mediated liver cancer and its species differences. Expert Opin Drug Metab Toxicol 2020; 16:343-351. [PMID: 32202166 DOI: 10.1080/17425255.2020.1746268] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Introduction: The nuclear receptor CAR plays an important role in the regulation of hepatic responses to xenobiotic exposure, including the induction of hepatocyte proliferation and chemical carcinogenesis. Phenobarbital, a well-known liver cancer promoter, has been found to promote hepatocyte proliferation via CAR activation. However, the molecular mechanisms by which CAR induces liver carcinogenesis remain unknown. In addition, it is believed that CAR-mediated liver carcinogenesis shows a species difference; phenobarbital treatment induces hepatocyte proliferation and liver cancer in rodents but not in humans. However, the mechanisms are also unknown.Areas covered: Several reports indicate that the key oncogenic signaling pathways Wnt/β-catenin and Hippo/YAP are involved in CAR-mediated liver carcinogenesis. We introduce current data about the possible molecular mechanisms involved in CAR-mediated liver carcinogenesis and species differences by focusing on these two signaling pathways.Expert opinion: CAR may activate both the Wnt/β-catenin and Hippo/YAP signaling pathways. The synergistic activation of both signaling pathways seems to be important for CAR-mediated liver cancer development. Low homology between the ligand binding domains of human CAR and rodent CAR might cause species differences in the interactions with proteins that control the Wnt/β-catenin and Hippo/YAP pathways as well as liver cancer induction.
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Affiliation(s)
- Ryota Shizu
- Laboratory of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
| | - Kouichi Yoshinari
- Laboratory of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
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Yoshinari K. Role of Nuclear Receptors PXR and CAR in Xenobiotic-Induced Hepatocyte Proliferation and Chemical Carcinogenesis. Biol Pharm Bull 2020; 42:1243-1252. [PMID: 31366862 DOI: 10.1248/bpb.b19-00267] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nuclear receptors pregnane X receptor (PXR) and constitutive active/androstane receptor (CAR) are xenobiotic-responsible transcriptional factors that belong to the same subfamily and are expressed abundantly in the liver. They play crucial roles in various liver functions including xenobiotic disposition and energy metabolism. CAR is also involved in xenobiotic-induced hepatocyte proliferation and hepatocarcinogenesis in rodents. However, there are some open questions on the association between chemical carcinogenesis and these nuclear receptors. These include the molecular mechanism for CAR-mediated hepatocyte proliferation and hepatocarcinogenesis. Another important question is whether PXR is associated with hepatocyte proliferation. We have recently reported a novel and unique function of PXR associated with murine hepatocyte proliferation: PXR activation alone does not induce hepatocyte proliferation but accelerates hepatocyte proliferation induced by various types of stimuli including CAR- or peroxisome proliferator-activated receptor alpha activating compounds, liver injury, and growth factors. We have also reported a role of yes-associated protein (YAP), a transcriptional cofactor controlling organ size and cell growth under the Hippo pathway, in CAR-mediated hepatocyte proliferation in mice. In this review, I will introduce our recent results as well as related studies on the roles of PXR and CAR in xenobiotic-induced hepatocyte proliferation and their molecular mechanisms.
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Affiliation(s)
- Kouichi Yoshinari
- Laboratory of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka
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20
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Carazo A, Mladěnka P, Pávek P. Marine Ligands of the Pregnane X Receptor (PXR): An Overview. Mar Drugs 2019; 17:md17100554. [PMID: 31569349 PMCID: PMC6836225 DOI: 10.3390/md17100554] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 09/27/2019] [Accepted: 09/27/2019] [Indexed: 02/06/2023] Open
Abstract
Pregnane X Receptor (PXR) is a ligand-activated transcription factor which binds many structurally different molecules. The receptor is able to regulate the expression of a wide array of genes and is involved in cancer and different key physiological processes such as the metabolism of drugs/xenobiotics and endogenous compounds including lipids and carbohydrates, and inflammation. Algae, sponges, sea squirts, and other marine organisms are some of the species from which structurally new molecules have been isolated that have been subsequently identified in recent decades as ligands for PXR. The therapeutic potential of these natural compounds is promising in different areas and has recently resulted in the registration of trabectedin by the FDA as a novel antineoplastic drug. Apart from being potentially novel drugs, these compounds can also serve as models for the development of new molecules with improved activity. The aim of this review is to succinctly summarize the currently known natural molecules isolated from marine organisms with a proven ability to interact with PXR.
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Affiliation(s)
- Alejandro Carazo
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Charles University, Heyrovského 1203, Hradec Králové 500 05, Czech Republic.
| | - Přemysl Mladěnka
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Charles University, Heyrovského 1203, Hradec Králové 500 05, Czech Republic.
| | - Petr Pávek
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Charles University, Heyrovského 1203, Hradec Králové 500 05, Czech Republic.
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Jiang Y, Feng D, Ma X, Fan S, Gao Y, Fu K, Wang Y, Sun J, Yao X, Liu C, Zhang H, Xu L, Liu A, Gonzalez FJ, Yang Y, Gao B, Huang M, Bi H. Pregnane X Receptor Regulates Liver Size and Liver Cell Fate by Yes-Associated Protein Activation in Mice. Hepatology 2019; 69:343-358. [PMID: 30048004 PMCID: PMC6324985 DOI: 10.1002/hep.30131] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Accepted: 05/30/2018] [Indexed: 12/13/2022]
Abstract
Activation of pregnane X receptor (PXR), a nuclear receptor that controls xenobiotic and endobiotic metabolism, is known to induce liver enlargement, but the molecular signals and cell types responding to PXR-induced hepatomegaly remain unknown. In this study, the effect of PXR activation on liver enlargement and cell change was evaluated in several strains of genetically modified mice and animal models. Lineage labeling using AAV-Tbg-Cre-treated Rosa26EYFP mice or Sox9-CreERT , Rosa26EYFP mice was performed and Pxr-null mice or AAV Yap short hairpin RNA (shRNA)-treated mice were used to confirm the role of PXR or yes-associated protein (YAP). Treatment with selective PXR activators induced liver enlargement and accelerated regeneration in wild-type (WT) and PXR-humanized mice, but not in Pxr-null mice, by increase of cell size, induction of a regenerative hybrid hepatocyte (HybHP) reprogramming, and promotion of hepatocyte and HybHP proliferation. Mechanistically, PXR interacted with YAP and PXR activation induced nuclear translocation of YAP. Blockade of YAP abolished PXR-induced liver enlargement in mice. Conclusion: These findings revealed a function of PXR in enlarging liver size and changing liver cell fate by activation of the YAP signaling pathway. These results have implications for understanding the physiological functions of PXR and suggest the potential for manipulation of liver size and liver cell fate.
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Affiliation(s)
- Yiming Jiang
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Dechun Feng
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland, USA
| | - Xiaochao Ma
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Shicheng Fan
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Yue Gao
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Kaili Fu
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Ying Wang
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jiahong Sun
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Xinpeng Yao
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Conghui Liu
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Huizhen Zhang
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Leqian Xu
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Aiming Liu
- Medical School of Ningbo University, Ningbo, China
| | - Frank J. Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Yingzi Yang
- Harvard School of Dental Medicine, Boston, MA, USA
| | - Bin Gao
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland, USA
| | - Min Huang
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Huichang Bi
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China.,Correspondence to: Hui-chang Bi, Ph.D., School of Pharmaceutical Sciences, Sun Yat-sen University, 132# Waihuandong Road, Guangzhou University City, Guangzhou 510006, P. R. China, Phone: +86-20-39943470, Fax: +86-20-39943000,
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22
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Shehu AI, Ma X. Pregnane X receptor in drug-induced liver injury: Friend or foe? LIVER RESEARCH 2018. [DOI: 10.1016/j.livres.2018.12.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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23
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Mackowiak B, Hodge J, Stern S, Wang H. The Roles of Xenobiotic Receptors: Beyond Chemical Disposition. Drug Metab Dispos 2018; 46:1361-1371. [PMID: 29759961 PMCID: PMC6124513 DOI: 10.1124/dmd.118.081042] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 05/07/2018] [Indexed: 02/06/2023] Open
Abstract
Over the past 20 years, the ability of the xenobiotic receptors to coordinate an array of drug-metabolizing enzymes and transporters in response to endogenous and exogenous stimuli has been extensively characterized and well documented. The constitutive androstane receptor (CAR) and the pregnane X receptor (PXR) are the xenobiotic receptors that have received the most attention since they regulate the expression of numerous proteins important to drug metabolism and clearance and formulate a central defensive mechanism to protect the body against xenobiotic challenges. However, accumulating evidence has shown that these xenobiotic sensors also control many cellular processes outside of their traditional realms of xenobiotic metabolism and disposition, including physiologic and/or pathophysiologic responses in energy homeostasis, cell proliferation, inflammation, tissue injury and repair, immune response, and cancer development. This review will highlight recent advances in studying the noncanonical functions of xenobiotic receptors with a particular focus placed on the roles of CAR and PXR in energy homeostasis and cancer development.
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Affiliation(s)
- Bryan Mackowiak
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland
| | - Jessica Hodge
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland
| | - Sydney Stern
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland
| | - Hongbing Wang
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland
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Wang F, Wu Y, Xie X, Sun J, Chen W. Essential role of nuclear receptors for the evaluation of the benefits of bioactive herbal extracts on liver function. Pharmacotherapy 2018; 99:798-809. [DOI: 10.1016/j.biopha.2018.01.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 12/29/2017] [Accepted: 01/03/2018] [Indexed: 02/07/2023]
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Generation of a PXR reporter human induced pluripotent stem cell line (PXR-mCherry hiPSC) using the CRISPR/Cas9 system. Stem Cell Res 2018; 26:72-75. [DOI: 10.1016/j.scr.2017.12.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 12/04/2017] [Indexed: 12/27/2022] Open
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26
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Apte U, Bhushan B, Dadhania V. Hepatic Defenses Against Toxicity: Liver Regeneration and Tissue Repair. COMPREHENSIVE TOXICOLOGY 2018:368-396. [DOI: 10.1016/b978-0-12-801238-3.64918-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2025]
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Zeng H, Jiang Y, Chen P, Fan X, Li D, Liu A, Ma X, Xie W, Liu P, Gonzalez FJ, Huang M, Bi H. Schisandrol B protects against cholestatic liver injury through pregnane X receptors. Br J Pharmacol 2017; 174:672-688. [PMID: 28128437 DOI: 10.1111/bph.13729] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 01/22/2017] [Accepted: 01/23/2017] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE Currently, ursodeoxycholic acid and obeticholic acid are the only two FDA-approved drugs for cholestatic liver diseases. Thus, new therapeutic approaches need to be developed. Here we have evaluated the anti-cholestasis effects of Schisandrol B (SolB), a bioactive compound isolated from Schisandra sphenanthera. EXPERIMENTAL APPROACH Hepatoprotective effect of SolB against intrahepatic cholestasis, induced by lithocholic acid (LCA), was evaluated in mice. Metabolomic analysis and gene analysis were used to assess involvement of pregnane X receptor (PXR). Molecular docking, cell-based reporter gene analysis and knockout mice were used to demonstrate the critical role of the PXR pathway in the anti-cholestasis effects of SolB. KEY RESULTS SolB protected against LCA-induced intrahepatic cholestasis. Furthermore, therapeutic treatment with SolB decreased mortality in cholestatic mice. Metabolomics and gene analysis showed that SolB accelerated metabolism of bile acids, promoted bile acid efflux into the intestine, and induced hepatic expression of the PXR-target genes Cyp3a11, Ugt1a1, and Oatp2, which are involved in bile acid homeostasis. Mechanistic studies showed that SolB activated human PXR and up-regulated PXR target genes in human cell lines. Additionally, SolB did not protect Pxr-null mice from liver injury induced by intrahepatic cholestasis, thus providing genetic evidence that the effect of SolB was PXR-dependent. CONCLUSION AND IMPLICATIONS These findings provide direct evidence for the hepatoprotective effects of SolB against cholestasis by activating PXR. Therefore, SolB may provide a new and effective approach to the prevention and treatment of cholestatic liver diseases.
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Affiliation(s)
- Hang Zeng
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Yiming Jiang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Pan Chen
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Xiaomei Fan
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Dongshun Li
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Aiming Liu
- Medical School of Ningbo University, Ningbo, China
| | - Xiaochao Ma
- Center for Pharmacogenetics, Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA, USA
| | - Wen Xie
- Center for Pharmacogenetics, Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA, USA
| | - Peiqing Liu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Frank J Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Min Huang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Huichang Bi
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
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Rudraiah S, Zhang X, Wang L. Nuclear Receptors as Therapeutic Targets in Liver Disease: Are We There Yet? Annu Rev Pharmacol Toxicol 2016; 56:605-626. [PMID: 26738480 DOI: 10.1146/annurev-pharmtox-010715-103209] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Nuclear receptors (NR) are ligand-modulated transcription factors that play diverse roles in cell differentiation, development, proliferation, and metabolism and are associated with numerous liver pathologies such as cancer, steatosis, inflammation, fibrosis, cholestasis, and xenobiotic/drug-induced liver injury. The network of target proteins associated with NRs is extremely complex, comprising coregulators, small noncoding microRNAs, and long noncoding RNAs. The importance of NRs as targets of liver disease is exemplified by the number of NR ligands that are currently used in the clinics or in clinical trials with promising results. Understanding the regulation by NR during pathophysiological conditions, and identifying ligands for orphan NR, points to a potential therapeutic approach for patients with liver diseases. An overview of complex NR metabolic networks and their pharmacological implications in liver disease is presented here.
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Affiliation(s)
- Swetha Rudraiah
- Department of Physiology and Neurobiology and The Institute for Systems Genomics, University of Connecticut, Storrs, Connecticut 06269
| | - Xi Zhang
- Department of Physiology and Neurobiology and The Institute for Systems Genomics, University of Connecticut, Storrs, Connecticut 06269
| | - Li Wang
- Department of Physiology and Neurobiology and The Institute for Systems Genomics, University of Connecticut, Storrs, Connecticut 06269.,Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516.,Department of Internal Medicine, Section of Digestive Diseases, Yale University, New Haven, Connecticut 06520
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Pondugula SR, Pavek P, Mani S. Pregnane X Receptor and Cancer: Context-Specificity is Key. NUCLEAR RECEPTOR RESEARCH 2016; 3. [PMID: 27617265 DOI: 10.11131/2016/101198] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Pregnane X receptor (PXR) is an adopted orphan nuclear receptor that is activated by a wide-range of endobiotics and xenobiotics, including chemotherapy drugs. PXR plays a major role in the metabolism and clearance of xenobiotics and endobiotics in liver and intestine via induction of drug-metabolizing enzymes and drug-transporting proteins. However, PXR is expressed in several cancer tissues and the accumulating evidence strongly points to the differential role of PXR in cancer growth and progression as well as in chemotherapy outcome. In cancer cells, besides regulating the gene expression of enzymes and proteins involved in drug metabolism and transport, PXR also regulates other genes involved in proliferation, metastasis, apoptosis, anti-apoptosis, inflammation, and oxidative stress. In this review, we focus on the differential role of PXR in a variety of cancers, including prostate, breast, ovarian, endometrial, and colon. We also discuss the future directions to further understand the differential role of PXR in cancer, and conclude with the need to identify novel selective PXR modulators to target PXR in PXR-expressing cancers.
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Affiliation(s)
- Satyanarayana R Pondugula
- Department of Anatomy, Physiology and Pharmacology, Auburn University, Auburn, AL 36849, USA; Auburn University Research Initiative in Cancer, Auburn University, Auburn, AL 36849, USA
| | - Petr Pavek
- Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Heyrovského 1203, Hradec Králové 500 05, Czech Republic, European Union
| | - Sridhar Mani
- Albert Einstein Cancer Center, Albert Einstein College of Medicine, New York, NY 10461, USA
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Forced expression of fibroblast growth factor 21 reverses the sustained impairment of liver regeneration in hPPARα(PAC) mice due to dysregulated bile acid synthesis. Oncotarget 2016; 6:9686-700. [PMID: 25991671 PMCID: PMC4496390 DOI: 10.18632/oncotarget.3531] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 02/17/2015] [Indexed: 12/16/2022] Open
Abstract
Peroxisome proliferator activated receptor α (PPARα) stimulates hepatocellular proliferation is species-specific. Activation of mouse, but not human, PPARα induces hepatocellular proliferation, hepatomegaly, and liver cancer. Here we tested the hypothesis that human and mouse PPARα affects liver regeneration differentially. PPARα-humanized mice (hPPARα(PAC)) were similar to wild type mice in responding to fasting-induced PPARα signaling. However, these mouse livers failed to regenerate in response to partial hepatectomy (PH). The liver-to-body weight ratios did not recover even 3 months after PH in hPPARα(PAC). The mouse PPARα-mediated down-regulation of let-7c was absent in hPPARα(PAC), which might partially be responsible for impaired proliferation. After PH, hPPARα(PAC) displayed steatosis, necrosis, and inflammation mainly in periportal zone 1, which suggested bile-induced toxicity. Quantification of hepatic bile acids (BA) revealed BA overload with increased hydrophobic BA in hPPARα(PAC). Forced FGF21 expression in partial hepatectomized hPPARα(PAC) reduced hepatic steatosis, prevented focal necrosis, and restored liver mass. Compared to mouse PPARα, human PPARα has a reduced capacity to regulate metabolic pathways required for liver regeneration. In addition, FGF21 can compensate for the reduced ability of human PPARα in stimulating liver regeneration, which suggests the potential application of FGF21 in promoting hepatic growth in injured and steatotic livers in humans.
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Zeng H, Li D, Qin X, Chen P, Tan H, Zeng X, Li X, Fan X, Jiang Y, Zhou Y, Chen Y, Wang Y, Huang M, Bi H. Hepatoprotective Effects of Schisandra sphenanthera Extract against Lithocholic Acid-Induced Cholestasis in Male Mice Are Associated with Activation of the Pregnane X Receptor Pathway and Promotion of Liver Regeneration. Drug Metab Dispos 2016; 44:337-42. [PMID: 26658429 DOI: 10.1124/dmd.115.066969] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 11/16/2015] [Indexed: 02/13/2025] Open
Abstract
We previously reported that the ethanol extract of Schisandra sphenanthera [Wuzhi (WZ) tablet] significantly protects against acetaminophen-induced hepatoxicity. However, whether WZ exerts a protective effect against cholestasis remains unclear. In this study, the protective effect of WZ on lithocholic acid (LCA)-induced intrahepatic cholestasis in mice was characterized and the involved mechanisms were investigated. WZ pretreatment (350 mg/kg) with LCA significantly reversed liver necrosis and decreased serum alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase activity. More importantly, serum total bile acids and total bilirubin were also remarkably reduced. Quantitative reverse-transcription polymerase chain reaction and Western blot analysis showed that hepatic expression of pregnane X receptor (PXR) target genes such as CYP3A11 and UDP-glucuronosyltransferase (UGT) 1A1 were significantly increased by WZ treatment. Luciferase assays performed in LS174T cells illustrated that WZ extract and its six bioactive lignans could all activate human PXR. In addition, WZ treatment significantly promoted liver regeneration via inhibition of p53/p21 to induce cell proliferation-associated proteins such as cyclin D1 and proliferating cell nuclear antigen. In conclusion, WZ has a protective effect against LCA-induced intrahepatic cholestasis, partially owing to activation of the PXR pathway and promotion of liver regeneration.
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Affiliation(s)
- Hang Zeng
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
| | - Dongshun Li
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
| | - Xiaoling Qin
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
| | - Pan Chen
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
| | - Huasen Tan
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
| | - Xuezhen Zeng
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
| | - Xi Li
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
| | - Xiaomei Fan
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
| | - Yiming Jiang
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
| | - Yawen Zhou
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
| | - Yixin Chen
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
| | - Ying Wang
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
| | - Min Huang
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
| | - Huichang Bi
- School of Pharmaceutical Sciences (H.Z., D.L., H.T., X.Z., X.L., X.F., Y.J., Y.Z., Y.C., Y.W., M.H., H.B.) and First Affiliated Hospital (P.C.), Sun Yat-sen University, Guangzhou, China; and Guangdong Food and Drug Vocational College, Guangzhou, China (X.Q.)
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Liu HX, Keane R, Sheng L, Wan YJY. Implications of microbiota and bile acid in liver injury and regeneration. J Hepatol 2015; 63:1502-10. [PMID: 26256437 PMCID: PMC4654653 DOI: 10.1016/j.jhep.2015.08.001] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 07/15/2015] [Accepted: 08/02/2015] [Indexed: 02/07/2023]
Abstract
Studies examining the mechanisms by which the liver incurs injury and then regenerates usually focus on factors and pathways directly within the liver, neglecting the signaling derived from the gut-liver axis. The intestinal content is rich in microorganisms as well as metabolites generated from both the host and colonizing bacteria. Through the gut-liver axis, this complex "soup" exerts an immense impact on liver integrity and function. This review article summarizes data published in the past 30 years demonstrating the signaling derived from the gut-liver axis in relation to liver injury and regeneration. Due to the intricate networks of implicated pathways as well as scarcity of available mechanistic data, it seems that nutrigenomic, metabolomics, and microbiota profiling approaches are warranted to provide a better understanding regarding the interplay and impact between nutrition, bacteria, and host response in influencing liver function and healing. Therefore elucidating the possible molecular mechanisms that link microbiota alteration to host physiological response and vice versa.
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Affiliation(s)
- Hui-Xin Liu
- Department of Medical Pathology and Laboratory Medicine, University of California, Sacramento, CA, USA
| | - Ryan Keane
- Department of Medical Pathology and Laboratory Medicine, University of California, Sacramento, CA, USA
| | - Lili Sheng
- Department of Medical Pathology and Laboratory Medicine, University of California, Sacramento, CA, USA
| | - Yu-Jui Yvonne Wan
- Department of Medical Pathology and Laboratory Medicine, University of California, Sacramento, CA, USA.
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PXR stimulates growth factor-mediated hepatocyte proliferation by cross-talk with the FOXO transcription factor. Biochem J 2015; 473:257-66. [PMID: 26574435 DOI: 10.1042/bj20150734] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 11/16/2015] [Indexed: 11/17/2022]
Abstract
Growth factor-mediated hepatocyte proliferation is crucial in liver regeneration and the recovery of liver function after injury. The nuclear receptor, pregnane X receptor (PXR), is a key transcription factor for the xenobiotic-induced expression of genes associated with various liver functions. Recently, we reported that PXR activation stimulates xenobiotic-induced hepatocyte proliferation. In the present study, we investigated whether PXR activation also stimulates growth factor-mediated hepatocyte proliferation. In G0 phase-synchronized, immortalized mouse hepatocytes, serum or epidermal growth factor treatment increased cell growth and this growth was augmented by the expression of mouse PXR and co-treatment with pregnenolone 16α-carbonitrile (PCN), a PXR ligand. In a liver regeneration model using carbon tetrachloride, PCN treatment enhanced the injury-induced increase in the number of Ki-67-positive nuclei as well as Ccna2 and Ccnb1 mRNA levels in wild-type (WT) but not Pxr-null mice. Chronological analysis of this model demonstrated that PCN treatment shifted the maximum cell proliferation to an earlier time point and increased the number of M-phase cells at those time points. In WT but not Pxr-null mice, PCN treatment reduced hepatic mRNA levels of genes involved in the suppression of G0/G1- and G1/S-phase transition, e.g. Rbl2, Cdkn1a and Cdkn1b. Analysis of the Rbl2 promoter revealed that PXR activation inhibited its Forkhead box O3 (FOXO3)-mediated transcription. Finally, the PXR-mediated enhancement of hepatocyte proliferation was inhibited by the expression of dominant active FOXO3 in vitro. The results of the present study suggest that PXR activation stimulates growth factor-mediated hepatocyte proliferation in mice, at least in part, through inhibiting FOXO3 from accelerating cell-cycle progression.
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Ni H, Su B, Pan L, Li X, Zhu X, Chen X. Functional variants inPXRare associated with colorectal cancer susceptibility in Chinese populations. Cancer Epidemiol 2015; 39:972-7. [PMID: 26547791 DOI: 10.1016/j.canep.2015.10.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 10/27/2015] [Accepted: 10/27/2015] [Indexed: 12/17/2022]
Abstract
BACKGROUND As an important member of the steroid nuclear receptor family, recent research has suggested that PXR may play important roles in the development of multiple cancers. However, no well-designed studies has been conducted to investigate the associations between genetic polymorphisms of PXR and colorectal cancer (CRC) risk in Chinese populations. MATERIALS AND METHODS We performed a hospital-based case-control analysis to assess two genetic polymorphisms in the 3'-untranslated regions (3'-UTR) via allele-specific MALDI-TOF mass spectrometry assay and evaluated the associations between two polymorphisms and risk of CRC. RESULTS The PXR rs3814058C>T polymorphism was significantly associated with a higher risk of CRC (P<10-3), and the CT/TT variant genotypes had an increased CRC risk (adjusted odds ratio=1.54, 95% confidence interval=1.27-1.83) comparing CC genotype. In stratified analyses, rs3814058CT+TT genotypes was associated with increased risk among alcohol consumers (P=0.002). In vitro experiments indicated that the rs3814058C to rs3814058T transition gained a new binding of the microRNA hsa-miR-129-5p and decreased the PXR expression. CONCLUSIONS Our data suggest that the functional polymorphism rs3814058C>T in 3'-UTR of PXR may be a functional biomarker to predict risk of CRC.
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Affiliation(s)
- Haizhen Ni
- Department of Vascular Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, PR China
| | - Bofeng Su
- Department of Nephrology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, PR China
| | - Lemen Pan
- Department of Vascular Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, PR China
| | - Xueyan Li
- Department of Endoscopic Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, PR China
| | - Xixia Zhu
- Operating Room, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, PR China
| | - Xiangjian Chen
- Department of Endoscopic Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, PR China.
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Bitter A, Rümmele P, Klein K, Kandel BA, Rieger JK, Nüssler AK, Zanger UM, Trauner M, Schwab M, Burk O. Pregnane X receptor activation and silencing promote steatosis of human hepatic cells by distinct lipogenic mechanisms. Arch Toxicol 2015; 89:2089-2103. [PMID: 25182422 DOI: 10.1007/s00204-014-1348-x] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 08/25/2014] [Indexed: 12/20/2022]
Abstract
In addition to its well-characterized role in the regulation of drug metabolism and transport by xenobiotics, pregnane X receptor (PXR) critically impacts on lipid homeostasis. In mice, both ligand-dependent activation and knockout of PXR were previously shown to promote hepatic steatosis. To elucidate the respective pathways in human liver, we generated clones of human hepatoma HepG2 cells exhibiting different PXR protein levels, and analyzed effects of PXR activation and knockdown on steatosis and expression of lipogenic genes. Ligand-dependent activation as well as knockdown of PXR resulted in increased steatosis in HepG2 cells. Activation of PXR induced the sterol regulatory element-binding protein (SREBP) 1-dependent lipogenic pathway via PXR-dependent induction of SREBP1a, which was confirmed in primary human hepatocytes. Inhibiting SREBP1 activity by blocking the cleavage-dependent maturation of SREBP1 protein impaired the induction of lipogenic SREBP1 target genes and triglyceride accumulation by PXR activation. On the other hand, PXR knockdown resulted in up-regulation of aldo-keto reductase (AKR) 1B10, which enhanced the acetyl-CoA carboxylase (ACC)-catalyzed reaction step of de novo lipogenesis. In a cohort of human liver samples histologically classified for non-alcoholic fatty liver disease, AKR1B10, SREBP1a and SREBP1 lipogenic target genes proved to be up-regulated in steatohepatitis, while PXR protein was reduced. In summary, our data suggest that activation and knockdown of PXR in human hepatic cells promote de novo lipogenesis and steatosis by induction of the SREBP1 pathway and AKR1B10-mediated increase of ACC activity, respectively, thus providing mechanistic explanations for a putative dual role of PXR in the pathogenesis of steatohepatitis.
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Affiliation(s)
- Andreas Bitter
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Auerbachstrasse 112, 70376, Stuttgart, Germany
| | - Petra Rümmele
- Institute of Pathology, University of Regensburg, Regensburg, Germany
| | - Kathrin Klein
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Auerbachstrasse 112, 70376, Stuttgart, Germany
| | - Benjamin A Kandel
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Auerbachstrasse 112, 70376, Stuttgart, Germany
| | - Jessica K Rieger
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Auerbachstrasse 112, 70376, Stuttgart, Germany
| | - Andreas K Nüssler
- Department of Traumatology, University of Tübingen, Tübingen, Germany
| | - Ulrich M Zanger
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Auerbachstrasse 112, 70376, Stuttgart, Germany
| | - Michael Trauner
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Matthias Schwab
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Auerbachstrasse 112, 70376, Stuttgart, Germany
- Department of Clinical Pharmacology, Institute of Experimental and Clinical Pharmacology and Toxicology, University Hospital, Tübingen, Germany
| | - Oliver Burk
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Auerbachstrasse 112, 70376, Stuttgart, Germany.
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Koutsounas I, Giaginis C, Alexandrou P, Zizi-Serbetzoglou A, Patsouris E, Kouraklis G, Theocharis S. Pregnane X Receptor Expression in Human Pancreatic Adenocarcinoma: Associations With Clinicopathologic Parameters, Tumor Proliferative Capacity, Patients' Survival, and Retinoid X Receptor Expression. Pancreas 2015; 44:1134-40. [PMID: 26355550 DOI: 10.1097/mpa.0000000000000405] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVES Pregnane X receptor (PXR) has been involved in human malignancy, either by directly affecting carcinogenesis or by inducing drug-drug interactions and chemotherapy resistance. The present study aimed to assess the clinical significance of PXR in pancreatic adenocarcinoma. METHODS Pregnane X receptor and its heterodimers' PXR/retinoid X receptor α (RXR-α), RXR-β, and RXR-γ expression were assessed immunohistochemically on tumoral samples from 55 pancreatic adenocarcinoma patients and were associated with clinicopathologic parameters, tumor proliferative capacity, and patients' survival. RESULTS Enhanced PXR expression was noted in 24 (43.6%) of 55 pancreatic adenocarcinoma cases. Pancreatic adenocarcinoma patients presenting increased histological grade of tumor differentiation showed a significant increased incidence of elevated PXR expression (P = 0.023). Enhanced PXR/RXR-β expression was significantly associated with smaller tumor size and earlier clinical stage (P = 0.005 and P = 0.003, respectively). Elevated PXR/RXR-γ expression was significantly associated with smaller tumor size and earlier clinical stage (P = 0.012 and P = 0.014, respectively) and borderline with the absence of lymph node metastases (P = 0.056). In addition, pancreatic adenocarcinoma patients presenting enhanced PXR/RXR-γ expression showed marginally longer survival times compared with those with decreased expression (log-rank test, P = 0.053). CONCLUSIONS This study supported evidence that PXR and its copartners' overexpression may be associated with favorable clinicopathologic parameters and better outcome in pancreatic adenocarcinoma.
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Affiliation(s)
- Ioannis Koutsounas
- From the *First Department of Pathology, Medical School, National and Kapodistrian University of Athens, Athens; †Department of Food Science and Nutrition, School of the Environment, University of the Aegean, Myrina, Lemnos; ‡Department of Pathology, Tzaneio General Hospital, Piraeus; and §Second Department of Propedeutic Surgery, Medical School, University of Athens, Athens, Greece
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Zou Y, Hu M, Lee J, Nambiar SM, Garcia V, Bao Q, Chan JY, Dai G. Nrf2 is essential for timely M phase entry of replicating hepatocytes during liver regeneration. Am J Physiol Gastrointest Liver Physiol 2015; 308:G262-8. [PMID: 25524062 PMCID: PMC4329475 DOI: 10.1152/ajpgi.00332.2014] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) regulates various cellular activities, including redox balance, detoxification, metabolism, autophagy, proliferation, and apoptosis. Several studies have demonstrated that Nrf2 regulates hepatocyte proliferation during liver regeneration. The aim of this study was to investigate how Nrf2 modulates the cell cycle of replicating hepatocytes in regenerating livers. Wild-type and Nrf2 null mice were subjected to 2/3 partial hepatectomy (PH) and killed at multiple time points for various analyses. Nrf2 null mice exhibited delayed liver regrowth, although the lost liver mass was eventually restored 7 days after PH. Nrf2 deficiency did not affect the number of hepatocytes entering the cell cycle but did delay hepatocyte mitosis. Mechanistically, the lack of Nrf2 resulted in increased mRNA and protein levels of hepatic cyclin A2 when the remaining hepatocytes were replicating in response to PH. Moreover, Nrf2 deficiency in regenerating livers caused dysregulation of Wee1, Cdc2, and cyclin B1 mRNA and protein expression, leading to decreased Cdc2 activity. Thus, Nrf2 is required for timely M phase entry of replicating hepatocytes by ensuring proper regulation of cyclin A2 and the Wee1/Cdc2/cyclin B1 pathway during liver regeneration.
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Affiliation(s)
- Yuhong Zou
- 1Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana;
| | - Min Hu
- 1Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana; ,2Department of Pathology, Anhui University of Traditional Chinese Medicine, Hefei, China; and
| | - Joonyong Lee
- 1Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana;
| | - Shashank Manohar Nambiar
- 1Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana;
| | - Veronica Garcia
- 1Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana;
| | - Qi Bao
- 1Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana;
| | - Jefferson Y. Chan
- 3Pathology and Laboratory Medicine, School of Medicine, University of California, Irvine, California
| | - Guoli Dai
- Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana;
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Fan M, Wang X, Xu G, Yan Q, Huang W. Bile acid signaling and liver regeneration. BIOCHIMICA ET BIOPHYSICA ACTA 2015; 1849:196-200. [PMID: 24878541 PMCID: PMC4246016 DOI: 10.1016/j.bbagrm.2014.05.021] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2014] [Revised: 04/20/2014] [Accepted: 05/20/2014] [Indexed: 12/25/2022]
Abstract
The liver is able to regenerate itself in response to partial hepatectomy or liver injury. This is accomplished by a complex network of different cell types and signals both inside and outside the liver. Bile acids (BAs) are recently identified as liver-specific metabolic signals and promote liver regeneration by activating their receptors: Farnesoid X Receptor (FXR) and G-protein-coupled BA receptor 1 (GPBAR1, or TGR5). FXR is a member of the nuclear hormone receptor superfamily of ligand-activated transcription factors. FXR promotes liver regeneration after 70% partial hepatectomy (PHx) or liver injury. Moreover, activation of FXR is able to alleviate age-related liver regeneration defects. Both liver- and intestine-FXR are activated by BAs after liver resection or injury and promote liver regeneration through distinct mechanism. TGR5 is a membrane-bound BA receptor and it is also activated during liver regeneration. TGR5 regulates BA hydrophobicity and stimulates BA excretion in urine during liver regeneration. BA signaling thus represents a novel metabolic pathway during liver regeneration. This article is part of a Special Issue entitled: Nuclear receptors in animal development.
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Affiliation(s)
- Mingjie Fan
- Institute of Genetics, College of Life Science, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, China
| | - Xichun Wang
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute, City of Hope National Medical Center, 1500 E. Duarte Road, Duarte, CA 91010, USA
| | - Ganyu Xu
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute, City of Hope National Medical Center, 1500 E. Duarte Road, Duarte, CA 91010, USA
| | - Qingfeng Yan
- Institute of Genetics, College of Life Science, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, China
| | - Wendong Huang
- Institute of Genetics, College of Life Science, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang 310058, China; Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute, City of Hope National Medical Center, 1500 E. Duarte Road, Duarte, CA 91010, USA.
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Meng Q, Chen X, Wang C, Liu Q, Sun H, Sun P, Peng J, Liu K. Alisol B 23-acetate promotes liver regeneration in mice after partial hepatectomy via activating farnesoid X receptor. Biochem Pharmacol 2014; 92:289-298. [PMID: 25278094 DOI: 10.1016/j.bcp.2014.09.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 09/03/2014] [Accepted: 09/08/2014] [Indexed: 02/08/2023]
Abstract
Liver resection has become a common treatment for liver tumors and hepatocellular carcinoma over the past decades. However, after surgery, the remnant livers in some patients fail to regenerate. Therefore, there is an urgent medical need to develop drugs that can promote liver regeneration. The purpose of the current study is to investigate the promotive effect of alisol B 23-acetate (AB23A) on liver regeneration in mice following partial hepatectomy (PH), and further elucidate the involvement of farnesoid X receptor (FXR) in the liver regeneration-promotive effect using in vivo and in vitro experiments. The results showed that AB23A dose-dependently promoted hepatocyte proliferation via upregulating hepatocyte proliferation-related protein forkhead box M1b (FoxM1b), Cyclin D1 and Cyclin B1 expression, and attenuated liver injury via an inhibition in Cyp7a1 and an induction in efflux transporters Bsep expression resulting in reduced hepatic bile acid levels. These changes in the genes, as well as accelerated liver regeneration in AB23A-treated mice were abrogated by FXR antagonist guggulsterone in vivo. In vitro evidences also directly showed the regulation of these genes by AB23A was abrogated when FXR was silenced. Luciferase reporter assay in HepG2 cells and molecular docking further demonstrated the effect of AB23A on FXR activation in vitro. In conclusions, AB23A produces promotive effect on liver regeneration, due to FXR-mediated regulation of genes involved in hepatocyte proliferation and hepato-protection. AB23A has the potential to be a novel therapeutic option for facilitating efficient liver regeneration in patients subjected to liver resection.
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Affiliation(s)
- Qiang Meng
- Department of Clinical Pharmacology, College of Pharmacy, Dalian Medical University, 9 West Section, Lvshun South Road, Lvshunkou District, Dalian 116044, China
| | - Xinli Chen
- Department of Clinical Pharmacology, College of Pharmacy, Dalian Medical University, 9 West Section, Lvshun South Road, Lvshunkou District, Dalian 116044, China
| | - Changyuan Wang
- Department of Clinical Pharmacology, College of Pharmacy, Dalian Medical University, 9 West Section, Lvshun South Road, Lvshunkou District, Dalian 116044, China
| | - Qi Liu
- Department of Clinical Pharmacology, College of Pharmacy, Dalian Medical University, 9 West Section, Lvshun South Road, Lvshunkou District, Dalian 116044, China
| | - Huijun Sun
- Department of Clinical Pharmacology, College of Pharmacy, Dalian Medical University, 9 West Section, Lvshun South Road, Lvshunkou District, Dalian 116044, China
| | - Pengyuan Sun
- Department of Clinical Pharmacology, College of Pharmacy, Dalian Medical University, 9 West Section, Lvshun South Road, Lvshunkou District, Dalian 116044, China
| | - Jinyong Peng
- Department of Clinical Pharmacology, College of Pharmacy, Dalian Medical University, 9 West Section, Lvshun South Road, Lvshunkou District, Dalian 116044, China
| | - Kexin Liu
- Department of Clinical Pharmacology, College of Pharmacy, Dalian Medical University, 9 West Section, Lvshun South Road, Lvshunkou District, Dalian 116044, China.
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A functional polymorphism in the 3'-UTR of PXR interacts with smoking to increase lung cancer risk in southern and eastern Chinese smoker. Int J Mol Sci 2014; 15:17457-68. [PMID: 25268617 PMCID: PMC4227172 DOI: 10.3390/ijms151017457] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 06/17/2014] [Accepted: 08/06/2014] [Indexed: 12/13/2022] Open
Abstract
Pregnane X receptor (PXR) is an important member of the nuclear receptor superfamily that copes with various endobiotic and xenobiotic stimuli, such as carcinogens by regulating an array of environmental response genes. Low PXR expression has been shown to promote tumor initiation and metastasis. The aim of the current study was to investigate whether the single nucleotide polymorphisms (SNPs) of PXR could alter lung cancer susceptibility in Chinese by affecting the function or expression of PXR. We genotyped three putatively functional SNPs of PXR (i.e., rs3814055C>T, rs3732360C>T, and rs3814058C>T) and analyzed their associations with lung cancer risk in a two-stage case-control study with a total of 1559 lung cancer cases and 1679 controls in the southern and eastern Chinese population. We found that in comparison to the rs3814058CC common genotype, the rs3814058T variants (TC/TT) which is located in the 3'-untranslated region (3'-UTR) of PXR conferred a consistently increased risk of lung cancer in both the southern Chinese (odd ratios (OR) = 1.24, 95% confidence interval (CI) = 1.03−1.49) and the eastern Chinese (OR = 1.33, 95% CI = 1.02−1.75). The variants also significantly interacted with smoking on increasing cancer risk (p = 0.023). Moreover, lung cancer tissues with the rs3814058T variants showed significantly lower PXR expression than those with rs3814058CC genotype in the smokers (p = 0.041). These results suggested that the rs3814058C>T polymorphism of PXR interacts with smoking on increasing lung cancer risk in Chinese smokers, which might be a functional genetic biomarker for lung cancer.
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Zou Y, Lee J, Nambiar SM, Hu M, Rui W, Bao Q, Chan JY, Dai G. Nrf2 is involved in maintaining hepatocyte identity during liver regeneration. PLoS One 2014; 9:e107423. [PMID: 25222179 PMCID: PMC4164664 DOI: 10.1371/journal.pone.0107423] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Accepted: 08/10/2014] [Indexed: 12/18/2022] Open
Abstract
Nrf2, a central regulator of the cellular defense against oxidative stress and inflammation, participates in modulating hepatocyte proliferation during liver regeneration. It is not clear, however, whether Nrf2 regulates hepatocyte growth, an important cellular mechanism to regain the lost liver mass after partial hepatectomy (PH). To determine this, various analyses were performed in wild-type and Nrf2-null mice following PH. We found that, at 60 h post-PH, the vast majority of hepatocytes lacking Nrf2 reduced their sizes, activated hepatic progenitor markers (CD133, TWEAK receptor, and trefoil factor family 3), depleted HNF4α protein, and downregulated the expression of a group of genes critical for their functions. Thus, the identity of hepatocytes deficient in Nrf2 was transiently but massively impaired in response to liver mass loss. This event was associated with the coupling of protein depletion of hepatic HNF4α, a master regulator of hepatocyte differentiation, and concomitant inactivation of hepatic Akt1 and p70S6K, critical hepatocyte growth signaling molecules. We conclude that Nrf2 participates in maintaining newly regenerated hepatocytes in a fully differentiated state by ensuring proper regulation of HNF4α, Akt1, and p70S6K during liver regeneration.
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Affiliation(s)
- Yuhong Zou
- Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University, Indianapolis, IN, United States of America
| | - Joonyong Lee
- Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University, Indianapolis, IN, United States of America
| | - Shashank Manohar Nambiar
- Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University, Indianapolis, IN, United States of America
| | - Min Hu
- Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University, Indianapolis, IN, United States of America
| | - Wenjuan Rui
- Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University, Indianapolis, IN, United States of America
| | - Qi Bao
- Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University, Indianapolis, IN, United States of America
| | - Jefferson Y. Chan
- Pathology and Laboratory Medicine, School of Medicine, University of California Irvine, Irvine, CA, United States of America
| | - Guoli Dai
- Department of Biology, School of Science, Center for Regenerative Biology and Medicine, Indiana University-Purdue University, Indianapolis, IN, United States of America
- * E-mail:
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Vacca M, D'Amore S, Graziano G, D'Orazio A, Cariello M, Massafra V, Salvatore L, Martelli N, Murzilli S, Sasso GL, Mariani-Costantini R, Moschetta A. Clustering nuclear receptors in liver regeneration identifies candidate modulators of hepatocyte proliferation and hepatocarcinoma. PLoS One 2014; 9:e104449. [PMID: 25116592 PMCID: PMC4130532 DOI: 10.1371/journal.pone.0104449] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2014] [Accepted: 07/09/2014] [Indexed: 12/12/2022] Open
Abstract
Background & Aims Liver regeneration (LR) is a valuable model for studying mechanisms modulating hepatocyte proliferation. Nuclear receptors (NRs) are key players in the control of cellular functions, being ideal modulators of hepatic proliferation and carcinogenesis. Methods & Results We used a previously validated RT-qPCR platform to profile modifications in the expression of all 49 members of the NR superfamily in mouse liver during LR. Twenty-nine NR transcripts were significantly modified in their expression during LR, including fatty acid (peroxisome proliferator-activated receptors, PPARs) and oxysterol (liver X receptors, Lxrs) sensors, circadian masters RevErbα and RevErbβ, glucocorticoid receptor (Gr) and constitutive androxane receptor (Car). In order to detect the NRs that better characterize proliferative status vs. proliferating liver, we used the novel Random Forest (RF) analysis to selected a trio of down-regulated NRs (thyroid receptor alpha, Trα; farsenoid X receptor beta, Fxrβ; Pparδ) as best discriminators of the proliferating status. To validate our approach, we further studied PPARδ role in modulating hepatic proliferation. We first confirmed the suppression of PPARδ both in LR and human hepatocellular carcinoma at protein level, and then demonstrated that PPARδ agonist GW501516 reduces the proliferative potential of hepatoma cells. Conclusions Our data suggest that NR transcriptome is modulated in proliferating liver and is a source of biomarkers and bona fide pharmacological targets for the management of liver disease affecting hepatocyte proliferation.
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Affiliation(s)
- Michele Vacca
- Fondazione Mario Negri Sud, Santa Maria Imbaro (Chieti), Chieti, Italy
- Unit of General Pathology, Aging Research Center (Ce.S.I.), “Gabriele D'Annunzio” University and Foundation, Chieti, Italy
- Interdisciplinary Department of Medicine, “Aldo Moro” University of Bari, Bari, Italy
| | - Simona D'Amore
- National Cancer Institute, IRCCS Oncologico “Giovanni Paolo II”, Bari, Italy
| | - Giusi Graziano
- National Cancer Institute, IRCCS Oncologico “Giovanni Paolo II”, Bari, Italy
| | - Andria D'Orazio
- Fondazione Mario Negri Sud, Santa Maria Imbaro (Chieti), Chieti, Italy
| | - Marica Cariello
- National Cancer Institute, IRCCS Oncologico “Giovanni Paolo II”, Bari, Italy
| | - Vittoria Massafra
- Fondazione Mario Negri Sud, Santa Maria Imbaro (Chieti), Chieti, Italy
| | - Lorena Salvatore
- Fondazione Mario Negri Sud, Santa Maria Imbaro (Chieti), Chieti, Italy
| | - Nicola Martelli
- Fondazione Mario Negri Sud, Santa Maria Imbaro (Chieti), Chieti, Italy
| | - Stefania Murzilli
- Fondazione Mario Negri Sud, Santa Maria Imbaro (Chieti), Chieti, Italy
| | - Giuseppe Lo Sasso
- Fondazione Mario Negri Sud, Santa Maria Imbaro (Chieti), Chieti, Italy
| | - Renato Mariani-Costantini
- Unit of General Pathology, Aging Research Center (Ce.S.I.), “Gabriele D'Annunzio” University and Foundation, Chieti, Italy
| | - Antonio Moschetta
- Interdisciplinary Department of Medicine, “Aldo Moro” University of Bari, Bari, Italy
- National Cancer Institute, IRCCS Oncologico “Giovanni Paolo II”, Bari, Italy
- * E-mail:
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Liu HX, Ly I, Hu Y, Wan YJY. Retinoic acid regulates cell cycle genes and accelerates normal mouse liver regeneration. Biochem Pharmacol 2014; 91:256-65. [PMID: 25087568 DOI: 10.1016/j.bcp.2014.07.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 06/30/2014] [Accepted: 07/01/2014] [Indexed: 02/01/2023]
Abstract
All-trans retinoic acid (RA) is a potent inducer of regeneration. Because the liver is the principal site for storage and bioactivation of vitamin A, the current study examines the effect of RA in mouse hepatocyte proliferation and liver regeneration. Mice that received a single dose of RA (25μg/g) by oral gavage developed hepatomegaly with increased number of Ki67-positive cells and induced expression of cell cycle genes in the liver. DNA binding data revealed that RA receptors retinoic acid receptor β (RARβ) and retinoid x receptor α (RXRα) bound to cell cycle genes Cdk1, Cdk2, Cyclin B, Cyclin E, and Cdc25a in mice with and without RA treatment. In addition, RA treatment induced novel binding of RARβ/RXRα to Cdk1, Cdk2, Cyclin D, and Cdk6 genes. All RARβ/RXRα binding sites contained AGGTCA-like motifs. RA treatment also promoted liver regeneration after partial hepatectomy (PH). RA signaling was implicated in normal liver regeneration as the mRNA levels of RARβ, Aldh1a2, Crabp1, and Crbp1 were all induced 1.5 days after PH during the active phase of hepatocyte proliferation. RA treatment prior to PH resulted in early up-regulation of RARβ, Aldh1a2, Crabp1, and Crbp1, which was accompanied by an early induction of cell cycle genes. Western blotting for RARβ, c-myc, Cyclin D, E, and A further supported the early induction of retinoid signal and cell proliferation by RA treatment. Taken together, our data suggest that RA may regulate cell cycle progression and accelerates liver regeneration. Such effect is associated with an early induction of RA signaling, which includes increased expression of the receptor, binding proteins, and processing enzyme for retinoids.
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Affiliation(s)
- Hui-Xin Liu
- Department of Medical Pathology and Laboratory Medicine, 4645 2nd Ave, Research Building III, University of California, Davis Health Systems, Sacramento, CA 95817,United States of America.
| | - Irene Ly
- Department of Medical Pathology and Laboratory Medicine, 4645 2nd Ave, Research Building III, University of California, Davis Health Systems, Sacramento, CA 95817,United States of America.
| | - Ying Hu
- Department of Medical Pathology and Laboratory Medicine, 4645 2nd Ave, Research Building III, University of California, Davis Health Systems, Sacramento, CA 95817,United States of America.
| | - Yu-Jui Yvonne Wan
- Department of Medical Pathology and Laboratory Medicine, 4645 2nd Ave, Research Building III, University of California, Davis Health Systems, Sacramento, CA 95817,United States of America.
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Niu Y, Wang Z, Huang H, Zhong S, Cai W, Xie Y, Shi G. Activated pregnane X receptor inhibits cervical cancer cell proliferation and tumorigenicity by inducing G2/M cell-cycle arrest. Cancer Lett 2014; 347:88-97. [PMID: 24486740 DOI: 10.1016/j.canlet.2014.01.026] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 01/02/2014] [Accepted: 01/24/2014] [Indexed: 02/05/2023]
Abstract
Pregnane X receptor (PXR) regulates cell proliferation and carcinogenesis in female reproductive tissue. We showed that PXR was expressed in cervical cells and tissue samples. PXR were lower or greatly diminished in cancer tissues compared to normal control. Functionally, activation of human PXR by rifampicin or ectopic expression of constitutively-activated human VP-PXR inhibited cervical cell proliferation. Constitutively-activated VP-PXR attenuated CaSki and HeLa xenograft tumor growth in nude mice compared with control. The cellular proliferation inhibition of PXR by causing G2/M cell-cycle arrest is involved up-regulation of Cullin1-3, MAD2L1, and down-regulation of ANAPC2 and CDKN1A. Our data suggests that PXR signaling inhibits tumor cell proliferation in vitro and cervical carcinoma growth in vivo.
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Affiliation(s)
- Yongdong Niu
- Department of Pharmacology, Shantou University Medical College, Guangdong, China
| | - Ziliang Wang
- Cancer Research Laboratory, Fudan University Shanghai Cancer Center, Department of Oncology, Fudan University, Shanghai, China
| | - Haihua Huang
- Department of Pathology, Second Affiliated Hospital of Shantou University Medical College, Guangdong, China
| | - Shuping Zhong
- Department of Biochemistry and Molecular Biology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Wenfeng Cai
- Department of Pharmacology, Shantou University Medical College, Guangdong, China
| | - Yangmin Xie
- Department of Experimental Animal Center, Medical College of Shantou University, Guangdong, China
| | - Ganggang Shi
- Department of Pharmacology, Shantou University Medical College, Guangdong, China.
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Jia Y, Viswakarma N, Reddy JK. Med1 subunit of the mediator complex in nuclear receptor-regulated energy metabolism, liver regeneration, and hepatocarcinogenesis. Gene Expr 2014; 16:63-75. [PMID: 24801167 PMCID: PMC4093800 DOI: 10.3727/105221614x13919976902219] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Several nuclear receptors regulate diverse metabolic functions that impact on critical biological processes, such as development, differentiation, cellular regeneration, and neoplastic conversion. In the liver, some members of the nuclear receptor family, such as peroxisome proliferator-activated receptors (PPARs), constitutive androstane receptor (CAR), farnesoid X receptor (FXR), liver X receptor (LXR), pregnane X receptor (PXR), glucocorticoid receptor (GR), and others, regulate energy homeostasis, the formation and excretion of bile acids, and detoxification of xenobiotics. Excess energy burning resulting from increases in fatty acid oxidation systems in liver generates reactive oxygen species, and the resulting oxidative damage influences liver regeneration and liver tumor development. These nuclear receptors are important sensors of exogenous activators as well as receptor-specific endogenous ligands. In this regard, gene knockout mouse models revealed that some lipid-metabolizing enzymes generate PPARα-activating ligands, while others such as ACOX1 (fatty acyl-CoA oxidase1) inactivate these endogenous PPARα activators. In the absence of ACOX1, the unmetabolized ACOX1 substrates cause sustained activation of PPARα, and the resulting increase in energy burning leads to hepatocarcinogenesis. Ligand-activated nuclear receptors recruit the multisubunit Mediator complex for RNA polymerase II-dependent gene transcription. Evidence indicates that the Med1 subunit of the Mediator is essential for PPARα, PPARγ, CAR, and GR signaling in liver. Med1 null hepatocytes fail to respond to PPARα activators in that these cells do not show induction of peroxisome proliferation and increases in fatty acid oxidation enzymes. Med1-deficient hepatocytes show no increase in cell proliferation and do not give rise to liver tumors. Identification of nuclear receptor-specific coactivators and Mediator subunits should further our understanding of the complexities of metabolic diseases associated with increased energy combustion in liver.
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Affiliation(s)
- Yuzhi Jia
- *Department of Pathology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Navin Viswakarma
- †Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago, Maywood, IL, USA
| | - Janardan K. Reddy
- *Department of Pathology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
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Martins IJ. Induction of NAFLD with Increased Risk of Obesity and Chronic Diseases in Developed Countries. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/ojemd.2014.44011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Carbamazepine promotes liver regeneration and survival in mice. J Hepatol 2013; 59:1239-45. [PMID: 23872603 DOI: 10.1016/j.jhep.2013.07.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/25/2012] [Revised: 07/03/2013] [Accepted: 07/05/2013] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS Carbamazepine (CBZ), a widely used anticonvulsant and mood stabilizer, activates multiple proliferative and pro-survival pathways. Here, we hypothesize that CBZ may promote hepatocellular proliferation and ameliorate liver regeneration. METHODS C57BL6/J mice were orally administered CBZ or vehicle and underwent a 70% partial hepatectomy (PHx), 85% PHx or treatment with carbon tetrachloride (CCl4). Liver regeneration was determined by liver to body weight ratio, hepatocyte proliferation markers, and activation of intracellular signalling pathways. RESULTS Two to 5days after the 70% PHx, the liver to body weight ratio was significantly higher in the CBZ-treated mice than in the vehicle-treated mice. CBZ treatment upregulated the number of proliferative hepatocytes following PHx or CCl4 treatment, as assessed by intrahepatic Ki-67 staining, BrdU uptake, and PCNA protein expression. PHx surgery induced the expression of several cyclins and activated Akt/mTOR signalling pathways, all of which were enhanced by CBZ treatment. The administration of the mTOR inhibitor temsirolimus abrogated the hepato-proliferative effect of CBZ. CBZ treatment significantly improved the survival rate of the mice that underwent lethal 85% massive hepatectomy. CONCLUSIONS CBZ demonstrated a novel hepato-proliferative effect through the activation of the mTOR signalling pathway in hepatectomised mice. CBZ has the potential to be a therapeutic option for facilitating efficient liver regeneration in patients subjected to liver surgery.
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Elucidating the metabolic regulation of liver regeneration. THE AMERICAN JOURNAL OF PATHOLOGY 2013; 184:309-21. [PMID: 24139945 DOI: 10.1016/j.ajpath.2013.04.034] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 03/26/2013] [Accepted: 04/01/2013] [Indexed: 02/08/2023]
Abstract
The regenerative capability of liver is well known, and the mechanisms that regulate liver regeneration are extensively studied. Such analyses have defined general principles that govern the hepatic regenerative response and implicated specific extracellular and intracellular signals as regulated during and essential for normal liver regeneration. Nevertheless, the most proximal events that stimulate liver regeneration and the distal signals that terminate this process remain incompletely understood. Recent data suggest that the metabolic response to hepatic insufficiency might be the proximal signal that initiates regenerative hepatocellular proliferation. This review provides an overview of the data in support of a metabolic model of liver regeneration and reflects on the clinical implications and areas for further study suggested by these findings.
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Kotta-Loizou I, Patsouris E, Theocharis S. Pregnane X receptor polymorphisms associated with human diseases. Expert Opin Ther Targets 2013; 17:1167-77. [DOI: 10.1517/14728222.2013.823403] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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