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Rajamani BM, Illangeswaran RSS, Benjamin ESB, Balakrishnan B, Jebanesan DZP, Das S, Pai AA, Vidhyadharan RT, Mohan A, Karathedath S, Abraham A, Mathews V, Velayudhan SR, Balasubramanian P. Modulating retinoid-X-receptor alpha (RXRA) expression sensitizes chronic myeloid leukemia cells to imatinib in vitro and reduces disease burden in vivo. Front Pharmacol 2023; 14:1187066. [PMID: 37324449 PMCID: PMC10264673 DOI: 10.3389/fphar.2023.1187066] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 05/18/2023] [Indexed: 06/17/2023] Open
Abstract
Introduction: The ligand-activated transcription factors, nuclear hormone receptors (NHRs), remain unexplored in hematological malignancies except for retinoic acid receptor alpha (RARA). Methods: Here we profiled the expression of various NHRs and their coregulators in Chronic myeloid leukemia (CML) cell lines and identified a significant differential expression pattern between inherently imatinib mesylate (IM)-sensitive and resistant cell lines. Results: Retinoid-X-receptor alpha (RXRA) was downregulated in CML cell lines inherently resistant to IM and in primary CML CD34+ cells. Pre-treatment with clinically relevant RXRA ligands improved sensitivity to IM in-vitro in both CML cell lines and primary CML cells. This combination effectively reduced the viability and colony-forming capacity of CML CD34+ cells in-vitro. In-vivo, this combination reduced leukemic burden and prolonged survival. Overexpression (OE) of RXRA inhibited proliferation and improved sensitivity to IM in-vitro. In-vivo, RXRA OE cells showed reduced engraftment of cells in the bone marrow, improved sensitivity to IM, and prolonged survival. Both RXRA OE and ligand treatment markedly reduced BCR::ABL1 downstream kinase activation, activating apoptotic cascades and improving sensitivity to IM. Importantly, RXRA OE also led to the disruption of the oxidative capacity of these cells. Conclusion: Combining IM with clinically available RXRA ligands could form an alternative treatment strategy in CML patients with suboptimal response to IM.
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Affiliation(s)
- Bharathi M. Rajamani
- Department of Haematology, Christian Medical College, Vellore, India
- Department of Biotechnology, Thiruvalluvar University, Vellore, India
| | | | - Esther Sathya Bama Benjamin
- Department of Haematology, Christian Medical College, Vellore, India
- Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, India
| | - Balaji Balakrishnan
- Department of Haematology, Christian Medical College, Vellore, India
- Department of Integrative Biology, School of Bio Sciences and Technology, Vellore Institute of Technology, Vellore, India
| | | | - Saswati Das
- Department of Haematology, Christian Medical College, Vellore, India
- Department of Biotechnology, Thiruvalluvar University, Vellore, India
| | - Aswin Anand Pai
- Department of Haematology, Christian Medical College, Vellore, India
- Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, India
| | | | - Ajith Mohan
- Department of Haematology, Christian Medical College, Vellore, India
| | | | - Aby Abraham
- Department of Haematology, Christian Medical College, Vellore, India
| | - Vikram Mathews
- Department of Haematology, Christian Medical College, Vellore, India
| | - Shaji R. Velayudhan
- Department of Haematology, Christian Medical College, Vellore, India
- Centre for Stem Cell Research (CSCR), A Unit of InStem Bengaluru, Christian Medical College Campus, Vellore, India
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2
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le Maire A, Rey M, Vivat V, Guée L, Blanc P, Malosse C, Chamot-Rooke J, Germain P, Bourguet W. Design and in vitro characterization of RXR variants as tools to investigate the biological role of endogenous rexinoids. J Mol Endocrinol 2022; 69:377-390. [PMID: 35900852 DOI: 10.1530/jme-22-0021] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 07/11/2022] [Indexed: 11/08/2022]
Abstract
Retinoid X receptors (RXRα, β, and γ) are essential members of the nuclear receptor (NR) superfamily of ligand-dependent transcriptional regulators that bind DNA response elements and control the expression of large gene networks. As obligate heterodimerization partners of many NRs, RXRs are involved in a variety of pathophysiological processes. However, despite this central role in NR signaling, there is still no consensus regarding the precise biological functions of RXRs and the putative role of the endogenous ligands (rexinoids) previously proposed for these receptors. Based on available crystal structures, we introduced a series of amino acid substitutions into the ligand-binding pocket of all three RXR subtypes in order to alter their binding properties. Subsequent characterization using a battery of cell-based and in vitro assays led to the identification of a double mutation abolishing the binding of any ligand while keeping the other receptor functions intact and a triple mutation that selectively impairs interaction with natural rexinoids but not with some synthetic ligands. We also report crystal structures that help understand the specific ligand-binding capabilities of both variants. These RXR variants, either fully disabled for ligand binding or retaining the property of being activated by synthetic compounds, represent unique tools that could be used in future studies to probe the presence of active endogenous rexinoids in tissues/organs and to investigate their role in vivo. Last, we provide data suggesting a possible involvement of fatty acids in the weak interaction of RXRs with corepressors.
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Affiliation(s)
- Albane le Maire
- CBS (Centre de Biologie Structurale), Univ Montpellier, CNRS, Inserm, Montpellier, France
| | - Martial Rey
- Institut Pasteur, Université de Paris, CNRS USR2000, Mass Spectrometry for Biology Unit, Paris, France
| | - Valérie Vivat
- IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire), Univ Strasbourg, CNRS, Inserm, Illkirch, France
| | - Laura Guée
- CBS (Centre de Biologie Structurale), Univ Montpellier, CNRS, Inserm, Montpellier, France
| | - Pauline Blanc
- CBS (Centre de Biologie Structurale), Univ Montpellier, CNRS, Inserm, Montpellier, France
| | - Christian Malosse
- Institut Pasteur, Université de Paris, CNRS USR2000, Mass Spectrometry for Biology Unit, Paris, France
| | - Julia Chamot-Rooke
- Institut Pasteur, Université de Paris, CNRS USR2000, Mass Spectrometry for Biology Unit, Paris, France
| | - Pierre Germain
- CBS (Centre de Biologie Structurale), Univ Montpellier, CNRS, Inserm, Montpellier, France
| | - William Bourguet
- CBS (Centre de Biologie Structurale), Univ Montpellier, CNRS, Inserm, Montpellier, France
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3
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Nyffeler J, Willis C, Harris FR, Taylor LW, Judson R, Everett LJ, Harrill JA. Combining phenotypic profiling and targeted RNA-Seq reveals linkages between transcriptional perturbations and chemical effects on cell morphology: Retinoic acid as an example. Toxicol Appl Pharmacol 2022; 444:116032. [PMID: 35483669 PMCID: PMC10894461 DOI: 10.1016/j.taap.2022.116032] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 04/11/2022] [Accepted: 04/12/2022] [Indexed: 10/18/2022]
Abstract
The United States Environmental Protection Agency has proposed a tiered testing strategy for chemical hazard evaluation based on new approach methods (NAMs). The first tier includes in vitro profiling assays applicable to many (human) cell types, such as high-throughput transcriptomics (HTTr) and high-throughput phenotypic profiling (HTPP). The goals of this study were to: (1) harmonize the seeding density of U-2 OS human osteosarcoma cells for use in both assays; (2) compare HTTr- versus HTPP-derived potency estimates for 11 mechanistically diverse chemicals; (3) identify candidate reference chemicals for monitoring assay performance in future screens; and (4) characterize the transcriptional and phenotypic changes in detail for all-trans retinoic acid (ATRA) as a model compound known for its adverse effects on osteoblast differentiation. The results of this evaluation showed that (1) HTPP conducted at low (400 cells/well) and high (3000 cells/well) seeding densities yielded comparable potency estimates and similar phenotypic profiles for the tested chemicals; (2) HTPP and HTTr resulted in comparable potency estimates for changes in cellular morphology and gene expression, respectively; (3) three test chemicals (etoposide, ATRA, dexamethasone) produced concentration-dependent effects on cellular morphology and gene expression that were consistent with known modes-of-action, demonstrating their suitability for use as reference chemicals for monitoring assay performance; and (4) ATRA produced phenotypic changes that were highly similar to other retinoic acid receptor activators (AM580, arotinoid acid) and some retinoid X receptor activators (bexarotene, methoprene acid). This phenotype was observed concurrently with autoregulation of the RARB gene. Both effects were prevented by pre-treating U-2 OS cells with pharmacological antagonists of their respective receptors. Thus, the observed phenotype could be considered characteristic of retinoic acid pathway activation in U-2 OS cells. These findings lay the groundwork for combinatorial screening of chemicals using HTTr and HTPP to generate complementary information for the first tier of a NAM-based chemical hazard evaluation strategy.
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Affiliation(s)
- Johanna Nyffeler
- Center for Computational Toxicology & Exposure, Office of Research and Development, US Environmental Protection Agency, Durham, NC 27711, United States of America; Oak Ridge Institute for Science and Education (ORISE) Postdoctoral Fellow, Oak Ridge, TN 37831, United States of America
| | - Clinton Willis
- Center for Computational Toxicology & Exposure, Office of Research and Development, US Environmental Protection Agency, Durham, NC 27711, United States of America
| | - Felix R Harris
- Center for Computational Toxicology & Exposure, Office of Research and Development, US Environmental Protection Agency, Durham, NC 27711, United States of America; Oak Ridge Associated Universities (ORAU) National Student Services Contractor, Oak Ridge, TN 37831, United States of America
| | - Laura W Taylor
- Center for Computational Toxicology & Exposure, Office of Research and Development, US Environmental Protection Agency, Durham, NC 27711, United States of America
| | - Richard Judson
- Center for Computational Toxicology & Exposure, Office of Research and Development, US Environmental Protection Agency, Durham, NC 27711, United States of America
| | - Logan J Everett
- Center for Computational Toxicology & Exposure, Office of Research and Development, US Environmental Protection Agency, Durham, NC 27711, United States of America
| | - Joshua A Harrill
- Center for Computational Toxicology & Exposure, Office of Research and Development, US Environmental Protection Agency, Durham, NC 27711, United States of America.
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4
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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: 10] [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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5
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Gangwar SK, Kumar A, Jose S, Alqahtani MS, Abbas M, Sethi G, Kunnumakkara AB. Nuclear receptors in oral cancer-emerging players in tumorigenesis. Cancer Lett 2022; 536:215666. [DOI: 10.1016/j.canlet.2022.215666] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 03/25/2022] [Accepted: 03/25/2022] [Indexed: 12/24/2022]
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6
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Upreti C, Woodruff CM, Zhang XL, Yim MJ, Zhou ZY, Pagano AM, Rehanian DS, Yin D, Kandel ER, Stanton PK, Nicholls RE. Loss of retinoid X receptor gamma subunit impairs group 1 mGluR mediated electrophysiological responses and group 1 mGluR dependent behaviors. Sci Rep 2021; 11:5552. [PMID: 33692389 PMCID: PMC7946894 DOI: 10.1038/s41598-021-84943-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 02/17/2021] [Indexed: 11/09/2022] Open
Abstract
Retinoid X receptors are members of the nuclear receptor family that regulate gene expression in response to retinoic acid and related ligands. Group 1 metabotropic glutamate receptors are G-protein coupled transmembrane receptors that activate intracellular signaling cascades in response to the neurotransmitter, glutamate. These two classes of molecules have been studied independently and found to play important roles in regulating neuronal physiology with potential clinical implications for disorders such as depression, schizophrenia, Parkinson's and Alzheimer's disease. Here we show that mice lacking the retinoid X receptor subunit, RXRγ, exhibit impairments in group 1 mGluR-mediated electrophysiological responses at hippocampal Schaffer collateral-CA1 pyramidal cell synapses, including impaired group 1 mGluR-dependent long-term synaptic depression (LTD), reduced group 1 mGluR-induced calcium release, and loss of group 1 mGluR-activated voltage-sensitive currents. These animals also exhibit impairments in a subset of group 1 mGluR-dependent behaviors, including motor performance, spatial object recognition, and prepulse inhibition. Together, these observations demonstrate convergence between the RXRγ and group 1 mGluR signaling pathways that may function to coordinate their regulation of neuronal activity. They also identify RXRγ as a potential target for the treatment of disorders in which group 1 mGluR signaling has been implicated.
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Affiliation(s)
- Chirag Upreti
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, 10595, USA
| | - Caitlin M Woodruff
- Department of Neuroscience, Columbia University, 3227 Broadway, New York, NY, 10027, USA
| | - Xiao-Lei Zhang
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, 10595, USA
| | - Michael J Yim
- Department of Neuroscience, Columbia University, 3227 Broadway, New York, NY, 10027, USA
| | - Zhen-Yu Zhou
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, 10595, USA.,Department of Neurology, New York Medical College, Valhalla, NY, 10595, USA
| | - Andrew M Pagano
- Department of Neuroscience, Columbia University, 3227 Broadway, New York, NY, 10027, USA
| | - Dina S Rehanian
- Department of Pathology and Cell Biology, Columbia University, 630 West 168thStreet, New York, NY, 10032, USA.,Taub Institute for Research on Alzheimer's Disease and Aging Brain, Columbia University, 630 West 168thStreet, New York, NY, 10032, USA
| | - Deqi Yin
- Department of Neuroscience, Columbia University, 3227 Broadway, New York, NY, 10027, USA.,Howard Hughes Medical Institute, Columbia University, 3227 Broadway, New York, NY, 10027, USA
| | - Eric R Kandel
- Department of Neuroscience, Columbia University, 3227 Broadway, New York, NY, 10027, USA.,Howard Hughes Medical Institute, Columbia University, 3227 Broadway, New York, NY, 10027, USA.,Kavli Institute for Brain Science, Columbia University, 3227 Broadway, New York, NY, 10027, USA.,Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University, 3227 Broadway, New York, NY, 10027, USA
| | - Patric K Stanton
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, 10595, USA.,Department of Neurology, New York Medical College, Valhalla, NY, 10595, USA
| | - Russell E Nicholls
- Department of Pathology and Cell Biology, Columbia University, 630 West 168thStreet, New York, NY, 10032, USA. .,Taub Institute for Research on Alzheimer's Disease and Aging Brain, Columbia University, 630 West 168thStreet, New York, NY, 10032, USA.
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7
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Barisón MJ, Pereira IT, Waloski Robert A, Dallagiovanna B. Reorganization of Metabolism during Cardiomyogenesis Implies Time-Specific Signaling Pathway Regulation. Int J Mol Sci 2021; 22:1330. [PMID: 33572750 PMCID: PMC7869011 DOI: 10.3390/ijms22031330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 01/06/2021] [Accepted: 01/08/2021] [Indexed: 11/17/2022] Open
Abstract
Understanding the cell differentiation process involves the characterization of signaling and regulatory pathways. The coordinated action involved in multilevel regulation determines the commitment of stem cells and their differentiation into a specific cell lineage. Cellular metabolism plays a relevant role in modulating the expression of genes, which act as sensors of the extra-and intracellular environment. In this work, we analyzed mRNAs associated with polysomes by focusing on the expression profile of metabolism-related genes during the cardiac differentiation of human embryonic stem cells (hESCs). We compared different time points during cardiac differentiation (pluripotency, embryoid body aggregation, cardiac mesoderm, cardiac progenitor and cardiomyocyte) and showed the immature cell profile of energy metabolism. Highly regulated canonical pathways are thoroughly discussed, such as those involved in metabolic signaling and lipid homeostasis. We reveal the critical relevance of retinoic X receptor (RXR) heterodimers in upstream retinoic acid metabolism and their relationship with thyroid hormone signaling. Additionally, we highlight the importance of lipid homeostasis and extracellular matrix component biosynthesis during cardiomyogenesis, providing new insights into how hESCs reorganize their metabolism during in vitro cardiac differentiation.
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Affiliation(s)
| | | | | | - Bruno Dallagiovanna
- Basic Stem Cell Biology Laboratory, Instituto Carlos Chagas-FIOCRUZ-PR, Rua Professor Algacyr Munhoz Mader, 3775, Curitiba, PR 81350-010, Brazil; (M.J.B.); (I.T.P.); (A.W.R.)
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8
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Diet Modifies Pioglitazone's Influence on Hepatic PPAR γ-Regulated Mitochondrial Gene Expression. PPAR Res 2020; 2020:3817573. [PMID: 32963510 PMCID: PMC7501566 DOI: 10.1155/2020/3817573] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/28/2020] [Accepted: 08/20/2020] [Indexed: 12/28/2022] Open
Abstract
Pioglitazone (Pio) is a thiazolidinedione (TZD) insulin-sensitizing drug whose effects result predominantly from its modulation of the transcriptional activity of peroxisome proliferator-activated-receptor-gamma (PPARγ). Pio is used to treat human insulin-resistant diabetes and also frequently considered for treatment of nonalcoholic steatohepatitis (NASH). In both settings, Pio's beneficial effects are believed to result primarily from its actions on adipose PPARγ activity, which improves insulin sensitivity and reduces the delivery of fatty acids to the liver. Nevertheless, a recent clinical trial showed variable efficacy of Pio in human NASH. Hepatocytes also express PPARγ, and such expression increases with insulin resistance and in nonalcoholic fatty liver disease (NAFLD). Furthermore, mice that overexpress hepatocellular PPARγ and Pio-treated mice with extrahepatic PPARγ gene disruption develop features of NAFLD. Thus, Pio's direct impact on hepatocellular gene expression might also be a determinant of this drug's ultimate influence on insulin resistance and NAFLD. Previous studies have characterized Pio's PPARγ-dependent effects on hepatic expression of specific adipogenic, lipogenic, and other metabolic genes. However, such transcriptional regulation has not been comprehensively assessed. The studies reported here address that consideration by genome-wide comparisons of Pio's hepatic transcriptional effects in wildtype (WT) and liver-specific PPARγ-knockout (KO) mice given either control or high-fat (HFD) diets. The results identify a large set of hepatic genes for which Pio's liver PPARγ-dependent transcriptional effects are concordant with its effects on RXR-DNA binding in WT mice. These data also show that HFD modifies Pio's influence on a subset of such transcriptional regulation. Finally, our findings reveal a broader influence of Pio on PPARγ-dependent hepatic expression of nuclear genes encoding mitochondrial proteins than previously recognized. Taken together, these studies provide new insights about the tissue-specific mechanisms by which Pio affects hepatic gene expression and the broad scope of this drug's influence on such regulation.
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9
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Wang D, Hiebl V, Schachner D, Ladurner A, Heiss EH, Atanasov AG, Dirsch VM. Soraphen A enhances macrophage cholesterol efflux via indirect LXR activation and ABCA1 upregulation. Biochem Pharmacol 2020; 177:114022. [DOI: 10.1016/j.bcp.2020.114022] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 05/07/2020] [Indexed: 12/31/2022]
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10
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Sun Y, Zhai G, Li R, Zhou W, Li Y, Cao Z, Wang N, Li H, Wang Y. RXRα Positively Regulates Expression of the Chicken PLIN1 Gene in a PPARγ-Independent Manner and Promotes Adipogenesis. Front Cell Dev Biol 2020; 8:349. [PMID: 32478078 PMCID: PMC7240111 DOI: 10.3389/fcell.2020.00349] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 04/20/2020] [Indexed: 12/24/2022] Open
Abstract
Perilipin1 (PLIN1), the most abundant lipid droplet (LD)-associated protein, plays a vital role in regulating lipid storage and breakdown in adipocytes. Recently, we found that the overexpression of PLIN1 promotes chicken preadipocyte lipid accumulation. However, the mechanisms by which transcription of the chicken PLIN1 gene is regulated remain unknown. In this study, we investigated the role of retinoid X receptor α (RXRα) in transcription of the chicken PLIN1 gene. Notably, reporter gene and expression assays showed that RXRα activates transcription of the chicken PLIN1 gene in a PPARγ-independent manner. Furthermore, promoter deletion and electrophoretic mobility shift assay (EMSA) analysis revealed that the chicken PLIN1 gene promoter region (-774/-785) contains an RXRα-binding site. Further study demonstrated that RXRα overexpression promotes differentiation of an immortalized chicken preadipocyte cell line (ICP1), causing a concomitant increase in PLIN1 transcripts. Taken together, our results show for the first time that RXRα activates transcription of the chicken PLIN1 gene in a PPARγ-independent manner, which might be at least in part responsible for RXRα-induced adipogenesis.
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Affiliation(s)
- Yuhang Sun
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin, China.,Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, Harbin, China.,College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Guiying Zhai
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin, China.,Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, Harbin, China.,College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Rui Li
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin, China.,Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, Harbin, China.,College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Weinan Zhou
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin, China.,Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, Harbin, China.,College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Yumao Li
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin, China.,Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, Harbin, China.,College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Zhiping Cao
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin, China.,Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, Harbin, China.,College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Ning Wang
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin, China.,Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, Harbin, China.,College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Hui Li
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin, China.,Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, Harbin, China.,College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
| | - Yuxiang Wang
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture and Rural Affairs, Harbin, China.,Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, Harbin, China.,College of Animal Science and Technology, Northeast Agricultural University, Harbin, China
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11
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Hiebl V, Schachner D, Ladurner A, Heiss EH, Stangl H, Dirsch VM. Caco-2 Cells for Measuring Intestinal Cholesterol Transport - Possibilities and Limitations. Biol Proced Online 2020; 22:7. [PMID: 32308567 PMCID: PMC7149936 DOI: 10.1186/s12575-020-00120-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 04/01/2020] [Indexed: 12/19/2022] Open
Abstract
Background The human Caco-2 cell line is a common in vitro model of the intestinal epithelial barrier. As the intestine is a major interface in cholesterol turnover and represents a non-biliary pathway for cholesterol excretion, Caco-2 cells are also a valuable model for studying cholesterol homeostasis, including cholesterol uptake and efflux. Currently available protocols are, however, either sketchy or not consistent among different laboratories. Our aim was therefore to generate a collection of optimized protocols, considering the different approaches of the different laboratories and to highlight possibilities and limitations of measuring cholesterol transport with this cell line. Results We developed comprehensive and quality-controlled protocols for the cultivation of Caco-2 cells on filter inserts in a single tight monolayer. A cholesterol uptake as well as a cholesterol efflux assay is described in detail, including suitable positive controls. We further show that Caco-2 cells can be efficiently transfected for luciferase reporter gene assays in order to determine nuclear receptor activation, main transcriptional regulators of cholesterol transporters (ABCA1, ABCB1, ABCG5/8, NPC1L1). Detection of protein and mRNA levels of cholesterol transporters in cells grown on filter inserts can pose challenges for which we highlight essential steps and alternative approaches for consideration. A protocol for viability assays with cells differentiated on filter inserts is provided for the first time. Conclusions The Caco-2 cell line is widely used in the scientific community as model for the intestinal epithelium, although with highly divergent protocols. The herein provided information and protocols can be a common basis for researchers intending to use Caco-2 cells in the context of cellular cholesterol homeostasis.
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Affiliation(s)
- Verena Hiebl
- 1Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Daniel Schachner
- 1Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Angela Ladurner
- 1Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Elke H Heiss
- 1Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Herbert Stangl
- 2Institute of Medical Chemistry, Center for Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Verena M Dirsch
- 1Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
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12
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le Maire A, Germain P, Bourguet W. Protein-protein interactions in the regulation of RAR–RXR heterodimers transcriptional activity. Methods Enzymol 2020; 637:175-207. [DOI: 10.1016/bs.mie.2020.02.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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13
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Two Opposing Faces of Retinoic Acid: Induction of Stemness or Induction of Differentiation Depending on Cell-Type. Biomolecules 2019; 9:biom9100567. [PMID: 31590252 PMCID: PMC6843238 DOI: 10.3390/biom9100567] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/01/2019] [Accepted: 10/01/2019] [Indexed: 12/12/2022] Open
Abstract
Stem cells have the capacity of self-renewal and, through proliferation and differentiation, are responsible for the embryonic development, postnatal development, and the regeneration of tissues in the adult organism. Cancer stem cells, analogous to the physiological stem cells, have the capacity of self-renewal and may account for growth and recurrence of tumors. Development and regeneration of healthy tissues and tumors depend on the balance of different genomic and nongenomic signaling pathways that regulate stem cell quiescence, proliferation, and differentiation. During evolution, this balance became dependent on all-trans retinoic acid (RA), a molecule derived from the environmental factor vitamin A. Here we summarize some recent findings on the prominent role of RA on the proliferation of stem and progenitor cells, in addition to its well-known function as an inductor of cell differentiation. A better understanding of the regulatory mechanisms of stemness and cell differentiation by RA may improve the therapeutic options of this molecule in regenerative medicine and cancer.
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14
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Regulation of Myelination by Exosome Associated Retinoic Acid Release from NG2-Positive Cells. J Neurosci 2019; 39:3013-3027. [PMID: 30760627 PMCID: PMC6468108 DOI: 10.1523/jneurosci.2922-18.2019] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 01/15/2019] [Accepted: 02/03/2019] [Indexed: 02/07/2023] Open
Abstract
In the CNS, oligodendrocytes are responsible for myelin formation and maintenance. Following spinal cord injury, oligodendrocyte loss and an inhibitory milieu compromise remyelination and recovery. Here, we explored the role of retinoic acid receptor-beta (RARβ) signaling in remyelination. Using a male Sprague Dawley rat model of PNS-CNS injury, we show that oral treatment with a novel drug like RARβ agonist, C286, induces neuronal expression of the proteoglycan decorin and promotes myelination and differentiation of oligodendrocyte precursor cells (NG2+ cells) in a decorin-mediated neuron–glia cross talk. Decorin promoted the activation of RARα in NG2+ cells by increasing the availability of the endogenous ligand RA. NG2+ cells synthesize RA, which is released in association with exosomes. We found that decorin prevents this secretion through regulation of the EGFR–calcium pathway. Using functional and pharmacological studies, we further show that RARα signaling is both required and sufficient for oligodendrocyte differentiation. These findings illustrate that RARβ and RARα are important regulators of oligodendrocyte differentiation, providing new targets for myelination. SIGNIFICANCE STATEMENT This study identifies novel therapeutic targets for remyelination after PNS-CNS injury. Pharmacological and knock-down experiments show that the retinoic acid (RA) signaling promotes differentiation of oligodendrocyte precursor cells (OPCs) and remyelination in a cross talk between neuronal RA receptor-beta (RARβ) and RARα in NG2+ cells. We show that stimulation of RARα is required for the differentiation of OPCs and we describe for the first time how oral treatment with a RARβ agonist (C286, currently being tested in a Phase 1 trial, ISRCTN12424734) leads to the endogenous synthesis of RA through retinaldehyde dehydrogenase 2 (Raldh2) in NG2 cells and controls exosome-associated-RA intracellular levels through a decorin–Ca2+ pathway. Although RARβ has been implicated in distinct aspects of CNS regeneration, this study identifies a novel function for both RARβ and RARα in remyelination.
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15
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Osz J, McEwen AG, Wolf J, Poussin-Courmontagne P, Peluso-Iltis C, Chebaro Y, Kieffer B, Rochel N. Modulation of RXR-DNA complex assembly by DNA context. Mol Cell Endocrinol 2019; 481:44-52. [PMID: 30476562 DOI: 10.1016/j.mce.2018.11.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 11/15/2018] [Accepted: 11/22/2018] [Indexed: 01/16/2023]
Abstract
Retinoid X Receptors (RXRs) act as dimer partners for several nuclear receptors including itself, binding to genomic DNA response elements and regulating gene transcription with cell and gene specificity. As homodimers, RXRs bind direct repeats of the half-site (A/G)G(G/T)TCA separated by 1 nucleotide (DR1) and little variability of this consensus site is observed for natural DR1s. However, these variations are responsible of the modulation of RXR receptors function through differential binding affinity and conformational changes. To further our understanding of the molecular mechanisms underlying RXR-DNA interactions, we examined how RXR DBDs bind to different DR1s using thermodynamics, X-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy. We show that the half-site sequences modulate the binding cooperativity that results from the protein-protein contacts between the two DBDs. Chemical shifts perturbation NMR experiments revealed that sequence variations in half-sites induce changes that propagate from the protein-DNA interface to the dimerization interface throughout the DBD fold.
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Affiliation(s)
- Judit Osz
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM), U1258/Centre National de la Recherche Scientifique (CNRS), UMR7104/Université de Strasbourg, 67404, Illkirch, France
| | - Alastair G McEwen
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM), U1258/Centre National de la Recherche Scientifique (CNRS), UMR7104/Université de Strasbourg, 67404, Illkirch, France
| | - Justine Wolf
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM), U1258/Centre National de la Recherche Scientifique (CNRS), UMR7104/Université de Strasbourg, 67404, Illkirch, France
| | - Pierre Poussin-Courmontagne
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM), U1258/Centre National de la Recherche Scientifique (CNRS), UMR7104/Université de Strasbourg, 67404, Illkirch, France
| | - Carole Peluso-Iltis
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM), U1258/Centre National de la Recherche Scientifique (CNRS), UMR7104/Université de Strasbourg, 67404, Illkirch, France
| | - Yassmine Chebaro
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM), U1258/Centre National de la Recherche Scientifique (CNRS), UMR7104/Université de Strasbourg, 67404, Illkirch, France
| | - Bruno Kieffer
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM), U1258/Centre National de la Recherche Scientifique (CNRS), UMR7104/Université de Strasbourg, 67404, Illkirch, France.
| | - Natacha Rochel
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM), U1258/Centre National de la Recherche Scientifique (CNRS), UMR7104/Université de Strasbourg, 67404, Illkirch, France.
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16
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Abstract
Resistance to vitamin D has been known for decades as vitamin D resistant rickets, caused by mutations of the gene encoding for vitamin D receptor (VDR). Findings of extra-skeletal effects of vitamin D and learning of the molecular mechanisms used by its biologically active metabolite calcitriol revealed other ways leading to its impaired sensitivity. Calcitriol takes advantage of both genomic and non-genomic mechanisms through its binding to vitamin D receptor, located not only in the cell nuclei but also in a perinuclear space. On the genomic level the complex of calcitriol bound to VDR binds to the DNA responsive elements of the controlled gene in concert with another nuclear receptor, retinoid X receptor, and expression of the VDR itself is controlled by its own ligand. These elements were found not only in the promotor region, but are scattered over the gene DNA. The gene expression includes a number of nuclear transcription factors which interact with the responsive elements and with each other and learning how they operate would further contribute to revealing causes of the impaired vitamin D sensitivity. Finally, the examples of major disorders are provided, associated with impairment of the vitamin D function and its receptor.
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Affiliation(s)
- L Máčová
- Institute of Endocrinology, Prague, Czech Republic.
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17
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Hiebl V, Ladurner A, Latkolik S, Dirsch VM. Natural products as modulators of the nuclear receptors and metabolic sensors LXR, FXR and RXR. Biotechnol Adv 2018; 36:1657-1698. [PMID: 29548878 DOI: 10.1016/j.biotechadv.2018.03.003] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 03/02/2018] [Accepted: 03/08/2018] [Indexed: 01/25/2023]
Abstract
Nuclear receptors (NRs) represent attractive targets for the treatment of metabolic syndrome-related diseases. In addition, natural products are an interesting pool of potential ligands since they have been refined under evolutionary pressure to interact with proteins or other biological targets. This review aims to briefly summarize current basic knowledge regarding the liver X (LXR) and farnesoid X receptors (FXR) that form permissive heterodimers with retinoid X receptors (RXR). Natural product-based ligands for these receptors are summarized and the potential of LXR, FXR and RXR as targets in precision medicine is discussed.
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Affiliation(s)
- Verena Hiebl
- University of Vienna, Department of Pharmacognosy, Althanstrasse 14, 1090 Vienna, Austria
| | - Angela Ladurner
- University of Vienna, Department of Pharmacognosy, Althanstrasse 14, 1090 Vienna, Austria.
| | - Simone Latkolik
- University of Vienna, Department of Pharmacognosy, Althanstrasse 14, 1090 Vienna, Austria
| | - Verena M Dirsch
- University of Vienna, Department of Pharmacognosy, Althanstrasse 14, 1090 Vienna, Austria
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18
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Rossetti S, Ren M, Visconti N, Corlazzoli F, Gagliostro V, Somenzi G, Yao J, Sun Y, Sacchi N. Tracing anti-cancer and cancer-promoting actions of all-trans retinoic acid in breast cancer to a RARα epigenetic mechanism of mammary epithelial cell fate. Oncotarget 2018; 7:87064-87080. [PMID: 27894085 PMCID: PMC5349971 DOI: 10.18632/oncotarget.13500] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 10/28/2016] [Indexed: 01/16/2023] Open
Abstract
A hallmark of cancer cells is the ability to evade the growth inhibitory/pro-apoptotic action of physiological all-trans retinoic acid (RA) signal, the bioactive derivative of Vitamin A. However, as we and others reported, RA can also promote cancer cell growth and invasion. Here we show that anticancer and cancer-promoting RA actions in breast cancer have roots in a mechanism of mammary epithelial cell morphogenesis that involves both transcriptional (epigenetic) and non-transcriptional RARα (RARA) functions. We found that the mammary epithelial cell-context specific degree of functionality of the RARA transcriptional (epigenetic) component of this mechanism, by tuning the effects of the non-transcriptional RARA component, determines different cell fate decisions during mammary morphogenesis. Indeed, factors that hamper the RARA epigenetic function make physiological RA drive aberrant morphogenesis via non-transcriptional RARA, thus leading to cell transformation. Remarkably, also the cell context-specific degree of functionality of the RARA epigenetic component retained by breast cancer cells is critical to determine cell fate decisions in response to physiological as well as supraphysiological RA variation. Overall this study supports the proof of principle that the epigenetic functional plasticity of the mammary epithelial cell RARA mechanism, which is essential for normal morphogenetic processes, is necessary to deter breast cancer onset/progression consequent to the insidious action of physiological RA.
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Affiliation(s)
- Stefano Rossetti
- Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - MingQiang Ren
- Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Nicolo Visconti
- Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Francesca Corlazzoli
- Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Vincenzo Gagliostro
- Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Giulia Somenzi
- Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Jin Yao
- The State University of New York at Buffalo, Center of Excellence in Bioinformatics and Life Sciences, Buffalo, NY 14203, USA
| | - Yijun Sun
- The State University of New York at Buffalo, Center of Excellence in Bioinformatics and Life Sciences, Buffalo, NY 14203, USA
| | - Nicoletta Sacchi
- Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
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19
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Chen L, Aleshin AE, Alitongbieke G, Zhou Y, Zhang X, Ye X, Hu M, Ren G, Chen Z, Ma Y, Zhang D, Liu S, Gao W, Cai L, Wu L, Zeng Z, Jiang F, Liu J, Zhou H, Cadwell G, Liddington RC, Su Y, Zhang XK. Modulation of nongenomic activation of PI3K signalling by tetramerization of N-terminally-cleaved RXRα. Nat Commun 2017; 8:16066. [PMID: 28714476 PMCID: PMC5520057 DOI: 10.1038/ncomms16066] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Accepted: 05/24/2017] [Indexed: 12/14/2022] Open
Abstract
Retinoid X receptor-alpha (RXRα) binds to DNA either as homodimers or heterodimers, but it also forms homotetramers whose function is poorly defined. We previously discovered that an N-terminally-cleaved form of RXRα (tRXRα), produced in tumour cells, activates phosphoinositide 3-kinase (PI3K) signalling by binding to the p85α subunit of PI3K and that K-80003, an anti-cancer agent, inhibits this process. Here, we report through crystallographic and biochemical studies that K-80003 binds to and stabilizes tRXRα tetramers via a ‘three-pronged’ combination of canonical and non-canonical mechanisms. K-80003 binding has no effect on tetramerization of RXRα, owing to the head–tail interaction that is absent in tRXRα. We also identify an LxxLL motif in p85α, which binds to the coactivator-binding groove on tRXRα and dissociates from tRXRα upon tRXRα tetramerization. These results identify conformational selection as the mechanism for inhibiting the nongenomic action of tRXRα and provide molecular insights into the development of RXRα cancer therapeutics. The transcription factor retinoid X receptor-alpha (RXRα) can also form homotetramers. Here the authors show that the anti-cancer agent K-80003 selectively inhibits the nongenomic action of N-terminally-cleaved RXRα in tumour cells by stabilizing its tetramerization but not that of full-length RXRα.
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Affiliation(s)
- Liqun Chen
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China.,College of Biological Science and Engineering, Fuzhou University, Fuzhou 350108, China.,Sanford Burnham Prebys Medical Discovery Institute, 10901, North Torrey Pines Road, La Jolla, California 92037, USA
| | - Alexander E Aleshin
- Sanford Burnham Prebys Medical Discovery Institute, 10901, North Torrey Pines Road, La Jolla, California 92037, USA
| | - Gulimiran Alitongbieke
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Yuqi Zhou
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Xindao Zhang
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Xiaohong Ye
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Mengjie Hu
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Gaoang Ren
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Ziwen Chen
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Yue Ma
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Duo Zhang
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Shuai Liu
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Weiwei Gao
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Lijun Cai
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Lingjuan Wu
- College of Biological Science and Engineering, Fuzhou University, Fuzhou 350108, China
| | - Zhiping Zeng
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Fuquan Jiang
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Jie Liu
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Hu Zhou
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China
| | - Gregory Cadwell
- Sanford Burnham Prebys Medical Discovery Institute, 10901, North Torrey Pines Road, La Jolla, California 92037, USA
| | - Robert C Liddington
- Sanford Burnham Prebys Medical Discovery Institute, 10901, North Torrey Pines Road, La Jolla, California 92037, USA
| | - Ying Su
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China.,Sanford Burnham Prebys Medical Discovery Institute, 10901, North Torrey Pines Road, La Jolla, California 92037, USA
| | - Xiao-Kun Zhang
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China.,Sanford Burnham Prebys Medical Discovery Institute, 10901, North Torrey Pines Road, La Jolla, California 92037, USA
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20
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Menéndez-Gutiérrez MP, Ricote M. The multi-faceted role of retinoid X receptor in bone remodeling. Cell Mol Life Sci 2017; 74:2135-2149. [PMID: 28105491 PMCID: PMC11107715 DOI: 10.1007/s00018-017-2458-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 12/20/2016] [Accepted: 01/04/2017] [Indexed: 02/07/2023]
Abstract
Retinoid X receptors (RXRs) form a unique subclass within the nuclear receptor (NR) superfamily of ligand-dependent transcription factors. RXRs are obligatory partners for a number of other NRs, placing RXRs in a coordinating role at the crossroads of multiple signaling pathways. In addition, RXRs can function as self-sufficient homodimers. Recent advances have revealed RXRs as novel regulators of osteoclastogenesis and bone remodeling. This review outlines the versatility of RXR action in the control of transcription of bone-forming osteoblasts and bone-resorbing osteoclasts, both through heterodimerization with other NRs and through RXR homodimerization. RXR signaling is currently a major therapeutic target and, therefore, knowledge of how RXR signaling affects bone remodeling creates enormous potential for the translation of basic research findings into successful clinical therapies to increase bone mass and improve bone quality.
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Affiliation(s)
- María P Menéndez-Gutiérrez
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Melchor Fernández Almagro, 3, 28029, Madrid, Spain
| | - Mercedes Ricote
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Melchor Fernández Almagro, 3, 28029, Madrid, Spain.
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21
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De Cosmo S, Mazzoccoli G. Retinoid X Receptors Intersect the Molecular Clockwork in the Regulation of Liver Metabolism. Front Endocrinol (Lausanne) 2017; 8:24. [PMID: 28243223 PMCID: PMC5303745 DOI: 10.3389/fendo.2017.00024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 01/27/2017] [Indexed: 12/25/2022] Open
Abstract
Liver metabolic pathways are driven by the biological clock, and appropriate timing of 24-h patterns of metabolic gene expression as well as anabolic/catabolic processes with wake-related activity/feeding and sleep-related resting/fasting cycles preserves hepatic healthiness. The interplay among the liver metabolic pathways and the molecular clockwork is geared by the nuclear receptors, and ligand-dependent transcription factors that gauge the cellular nutritional status and redox balance, bind hormones and metabolites, and modulate the transcription of thousands target genes through their DNA-binding domain. Several nuclear receptors in the liver oscillate with circadian rhythmicity, and among these, the retinoid X receptors play a key role in metabolism regulation, intersecting with the cogs of the molecular clockwork.
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Affiliation(s)
- Salvatore De Cosmo
- Department of Medical Sciences, Division of Internal Medicine and Chronobiology Unit, IRCCS “Ospedale Casa Sollievo della Sofferenza”, San Giovanni Rotondo, Italy
| | - Gianluigi Mazzoccoli
- Department of Medical Sciences, Division of Internal Medicine and Chronobiology Unit, IRCCS “Ospedale Casa Sollievo della Sofferenza”, San Giovanni Rotondo, Italy
- *Correspondence: Gianluigi Mazzoccoli,
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22
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Luo Q, Wang Z, Chen H, Fang MH, Xie S, Qian X, Lin X. Identification of Anticancer Drug Candidate Targeting Nuclear Receptor Retinoid X receptor-α from Natural Products using Receptor-Ligand Recognition. ChemistrySelect 2016. [DOI: 10.1002/slct.201600907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Qiang Luo
- Animal Husbandry and Fisheries Research Center; Guangdong Haid Group Co., Ltd.; Guangzhou China
- Institute of Hydrobiology; Chinese Academy of Science; Wuhan China
| | - Zhaokai Wang
- Engineering Research Center of Marine Biological Resource Comprehensive Utilization, Third Institute of Oceanography; State Oceanic Administration; Xiamen China
| | - Huibin Chen
- Engineering Research Center of Marine Biological Resource Comprehensive Utilization, Third Institute of Oceanography; State Oceanic Administration; Xiamen China
| | - Ms. Hui Fang
- Engineering Research Center of Marine Biological Resource Comprehensive Utilization, Third Institute of Oceanography; State Oceanic Administration; Xiamen China
| | - Shouqi Xie
- Institute of Hydrobiology; Chinese Academy of Science; Wuhan China
| | - Xueqiao Qian
- Animal Husbandry and Fisheries Research Center; Guangdong Haid Group Co., Ltd.; Guangzhou China
| | - Xiangzhi Lin
- Engineering Research Center of Marine Biological Resource Comprehensive Utilization, Third Institute of Oceanography; State Oceanic Administration; Xiamen China
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23
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Gu R, Xu J, Lin Y, Zhang J, Wang H, Sheng W, Ma D, Ma X, Huang G. Liganded retinoic acid X receptor α represses connexin 43 through a potential retinoic acid response element in the promoter region. Pediatr Res 2016; 80:159-68. [PMID: 26991262 DOI: 10.1038/pr.2016.47] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 09/28/2015] [Indexed: 11/10/2022]
Abstract
INTRODUCTION Retinoic acid X receptor alpha (RXRα) and Connexin 43 (Cx43) both play a crucial role in cardiogenesis. However, little is known about the interplay mechanism between the RXRα and Cx43. METHODS The activations of retinoic acid response element (RARE) in Cx43 were measured by luciferase transfection assay. Electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) was performed to prove that RXRα can directly bind to the RARE sequence. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were used to analyze the RXRα and Cx43 mRNA level and protein level in cells. RESULTS In this study, we confirmed the negative association of the gene expression between the RXRα and Cx43 in the cell level. Interestingly, a functional RARE was detected in the region from -1,426 to -314 base pairs upstream from the transcriptional start site of Cx43. Moreover, we also prove that RXRα can directly bind to this RARE sequence in vitro and in vivo. CONCLUSIONS RXRα negatively regulates the transcription and expression by directly binding to the RARE in the promoter of Cx43. The RARE-like sequence harbored in the Cx43 promoter region may serve as a functional RARE in the retinoic acid (RA) signaling pathway.
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Affiliation(s)
- Ruoyi Gu
- Children's Hospital of Fudan University, Shanghai, China
| | - Jun Xu
- Children's Hospital of Fudan University, Shanghai, China
| | - Yixiang Lin
- Children's Hospital of Fudan University, Shanghai, China
| | - Jing Zhang
- Children's Hospital of Fudan University, Shanghai, China.,Present address: Department of Pediatrics, Chengdu Women and Children's Medical Center, Sichuan, China
| | - Huijun Wang
- Children's Hospital of Fudan University, Shanghai, China.,Shanghai Key Laboratory of Birth Defects, Shanghai, China
| | - Wei Sheng
- Children's Hospital of Fudan University, Shanghai, China.,Shanghai Key Laboratory of Birth Defects, Shanghai, China
| | - Duan Ma
- Shanghai Key Laboratory of Birth Defects, Shanghai, China.,Key Laboratory of Molecular Medicine, Ministry of Education, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xiaojing Ma
- Children's Hospital of Fudan University, Shanghai, China.,Shanghai Key Laboratory of Birth Defects, Shanghai, China
| | - Guoying Huang
- Children's Hospital of Fudan University, Shanghai, China.,Shanghai Key Laboratory of Birth Defects, Shanghai, China
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24
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Fatty acid oxidation and carnitine palmitoyltransferase I: emerging therapeutic targets in cancer. Cell Death Dis 2016; 7:e2226. [PMID: 27195673 PMCID: PMC4917665 DOI: 10.1038/cddis.2016.132] [Citation(s) in RCA: 309] [Impact Index Per Article: 38.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Revised: 04/07/2016] [Accepted: 04/12/2016] [Indexed: 12/23/2022]
Abstract
Tumor cells exhibit unique metabolic adaptations that are increasingly viewed as potential targets for novel and specific cancer therapies. Among these targets, the carnitine palmitoyltransferase system is responsible for delivering the long-chain fatty acid (FA) from cytoplasm into mitochondria for oxidation, where carnitine palmitoyltransferase I (CPTI) catalyzes the rate-limiting step of fatty acid oxidation (FAO). With increasing understanding of the crucial role had by fatty acid oxidation in cancer, CPTI has received renewed attention as a pivotal mediator in cancer metabolic mechanism. CPTI activates FAO and fuels cancer growth via ATP and NADPH production, constituting an essential part of cancer metabolism adaptation. Moreover, CPTI also functionally intertwines with other key pathways and factors to regulate gene expression and apoptosis of cancer cell. Here, we summarize recent findings and update the current understanding of FAO and CPTI in cancer and provide theoretical basis for this enzyme as an emerging potential molecular target in cancer therapeutic intervention.
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Belorusova A, Osz J, Petoukhov MV, Peluso-Iltis C, Kieffer B, Svergun DI, Rochel N. Solution Behavior of the Intrinsically Disordered N-Terminal Domain of Retinoid X Receptor α in the Context of the Full-Length Protein. Biochemistry 2016; 55:1741-1748. [PMID: 26937780 DOI: 10.1021/acs.biochem.5b01122] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Retinoid X receptors (RXRs) are transcription factors with important functions in embryonic development, metabolic processes, differentiation, and apoptosis. A particular feature of RXRs is their ability to act as obligatory heterodimerization partners of class II nuclear receptors. At the same time, these receptors are also able to form homodimers that bind to direct repeat separated by one nucleotide hormone response elements. Since the discovery of RXRs, most of the studies focused on its ligand binding and DNA binding domains, while its N-terminal domain (NTD) harboring a ligand-independent activation function remained poorly characterized. Here, we investigated the solution properties of the NTD of RXRα alone and in the context of the full-length receptor using small-angle X-ray scattering and nuclear magnetic resonance spectroscopy. We report the solution structure of the full-length homodimeric RXRα on DNA and show that the NTD remains highly flexible within this complex.
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Affiliation(s)
- Anna Belorusova
- Department of Integrative Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM) U964 / Centre National de la Recherche Scientifique (CNRS) UMR 7104 / Université de Strasbourg, 67404 Illkirch, France
| | - Judit Osz
- Department of Integrative Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM) U964 / Centre National de la Recherche Scientifique (CNRS) UMR 7104 / Université de Strasbourg, 67404 Illkirch, France
| | - Maxim V Petoukhov
- European Molecular Biology Laboratory, Hamburg Outstation, Notkestrasse 85, 22603 Hamburg, Germany
| | - Carole Peluso-Iltis
- Department of Integrative Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM) U964 / Centre National de la Recherche Scientifique (CNRS) UMR 7104 / Université de Strasbourg, 67404 Illkirch, France
| | - Bruno Kieffer
- Department of Integrative Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM) U964 / Centre National de la Recherche Scientifique (CNRS) UMR 7104 / Université de Strasbourg, 67404 Illkirch, France
| | - Dmitri I Svergun
- European Molecular Biology Laboratory, Hamburg Outstation, Notkestrasse 85, 22603 Hamburg, Germany
| | - Natacha Rochel
- Department of Integrative Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale (INSERM) U964 / Centre National de la Recherche Scientifique (CNRS) UMR 7104 / Université de Strasbourg, 67404 Illkirch, France
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Nurr1 and Retinoid X Receptor Ligands Stimulate Ret Signaling in Dopamine Neurons and Can Alleviate α-Synuclein Disrupted Gene Expression. J Neurosci 2016; 35:14370-85. [PMID: 26490873 DOI: 10.1523/jneurosci.1155-15.2015] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
UNLABELLED α-synuclein, a protein enriched in Lewy bodies and highly implicated in neurotoxicity in Parkinson's disease, is distributed both at nerve terminals and in the cell nucleus. Here we show that a nuclear derivative of α-synuclein induces more pronounced changes at the gene expression level in mouse primary dopamine (DA) neurons compared to a derivative that is excluded from the nucleus. Moreover, by RNA sequencing we analyzed the extent of genome-wide effects on gene expression resulting from expression of human α-synuclein in primary mouse DA neurons. The results implicated the transcription factor Nurr1 as a key dysregulated target of α-synuclein toxicity. Forced Nurr1 expression restored the expression of hundreds of dysregulated genes in primary DA neurons expressing α-synuclein, and therefore prompted us to test the possibility that Nurr1 can be pharmacologically targeted by bexarotene, a ligand for the retinoid X receptor that forms heterodimers with Nurr1. Although our data demonstrated that bexarotene was ineffective in neuroprotection in rats in vivo, the results revealed that bexarotene has the capacity to coregulate subsets of Nurr1 target genes including the receptor tyrosine kinase subunit Ret. Moreover, bexarotene was able to restore dysfunctional Ret-dependent neurotrophic signaling in α-synuclein-overexpressing mouse DA neurons. These data highlight the role of the Nurr1-Ret signaling pathway as a target of α-synuclein toxicity and suggest that retinoid X receptor ligands with appropriate pharmacological properties could have therapeutic potential in Parkinson's disease. SIGNIFICANCE STATEMENT How α-synuclein, a protein enriched in Lewy bodies in Parkinson's disease, is causing neuropathology in dopamine neurons remains unclear. This study elucidated how α-synuclein is influencing gene expression and how Nurr1, a transcription factor known to protect dopamine neurons against α-synuclein toxicity, can counteract these effects. Moreover, given the protective role of Nurr1, this study also investigated how Nurr1 could be pharmacologically targeted via bexarotene, a ligand of Nurr1's heterodimerization partner retinoid X receptor (RXR). The results showed that RXR ligands could increase neurotrophic signaling, but provided a mixed picture of its potential in a Parkinson's disease rat model in vivo. However, this study clearly emphasized Nurr1's neuroprotective role and indicated that other RXR ligands could have therapeutic potential in Parkinson's disease.
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Review of the Structural and Dynamic Mechanisms of PPARγ Partial Agonism. PPAR Res 2015; 2015:816856. [PMID: 26435709 PMCID: PMC4578752 DOI: 10.1155/2015/816856] [Citation(s) in RCA: 124] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 08/19/2015] [Indexed: 01/02/2023] Open
Abstract
PPARγ (peroxisome proliferator activated receptor γ) is a ligand activated transcription factor of the nuclear receptor superfamily that controls the expression of a variety of genes involved in fatty acid metabolism, adipogenesis, and insulin sensitivity. While endogenous ligands of PPARγ include fatty acids and eicosanoids, synthetic full agonists of the receptor, including members of the thiazolidinedione (TZD) class, have been widely prescribed for the treatment of type II diabetes mellitus (T2DM). Unfortunately, the use of full agonists has been hampered by harsh side effects with some removed from the market in many countries. In contrast, partial agonists of PPARγ have been shown to retain favourable insulin sensitizing effects while exhibiting little to no side effects and thus represent a new potential class of therapeutics for the treatment of T2DM. Partial agonists have been found to not only display differences in transcriptional and cellular outcomes, but also act through distinct structural and dynamic mechanisms within the ligand binding cavity compared to full agonists.
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Yen PM. Classical nuclear hormone receptor activity as a mediator of complex biological responses: a look at health and disease. Best Pract Res Clin Endocrinol Metab 2015; 29:517-28. [PMID: 26303080 DOI: 10.1016/j.beem.2015.07.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Nuclear hormone receptors are a large family of receptors that bind a wide range of lipolic hormones and intracellular ligands. They act as ligand-inducible transcription factors to regulate the expression of target genes and play important roles in normal development, reproduction, and metabolism. NRs bind to hormones steroids, thyroid hormone, and vitamin D as well as metabolites of fatty acids, cholesterol, and bild acids. Orphan receptors are another group of NRs for which no known ligands have been identified yet but appear to have major roles in regulating intracellular metabolism. Targeting NRs has been a major source for the development of new drugs, particularly selective agonists and antagonists for cancer and metabolic diseases. Additionally, hormone resistance syndromes in man have enlarged our understanding of the functions of specific NRs and their isoforms as well as genetic mechanisms for phenotype expression.
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Affiliation(s)
- Paul Michael Yen
- Cardiovascular and Metabolic Disorders Program, Duke-NUS Graduate Medical School, Singapore.
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Additive Effects of Retinoic Acid (RA) and Bone Morphogenetic Protein 4 (BMP-4) Apoptosis Signaling in Retinoblastoma Cell Lines. PLoS One 2015; 10:e0131467. [PMID: 26173116 PMCID: PMC4501735 DOI: 10.1371/journal.pone.0131467] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 06/02/2015] [Indexed: 12/13/2022] Open
Abstract
Retinoids have been shown to serve promising therapeutic agents for human cancers, e.g. the treatment of neuroblastoma. Synthetic retinoids, specific for particular retinoic acid (RA) receptors, are tested as new therapy strategies. In the present study, application of recombinant retinoic acid (RA) lowers retinoblastoma (RB) cell viability and induces apoptosis in RB cell lines. Combined treatment of RA and bone morphogenetic protein 4 (BMP-4) increases the pro-apoptotic effect of RA in the RB cells lines WERI-Rb1, Y-79, RB355, RBL-30 and RBL-15, indicating an additive effect. We could show that in WERI-Rb1 cells RA/BMP-4 mediated cell death is at least partially caspase-dependent, whereby RA and BMP-4 additively increased (i) Apaf-1 mRNA levels, (ii) caspase-9 cleavage activity and (iii) the number of activated, cleaved caspase-3 positive cells. Compared to single application of RA and BMP-4, combined RA/BMP-4 treatment significantly augments mRNA levels of the retinoic acid receptors (RARs) RARα and RARß and the retinoic X receptor (RXR) RXRγ suggesting an interaction in the induction of these RA receptor subtypes in WERI-Rb1 cells. Agonist studies revealed that both, RARs and RXRs are involved in RA/BMP-4 mediated apoptosis in WERI-Rb1 retinoblastoma cells. Employing specific RAR subtype antagonists and a RXRß and RXRγ knockdown, we proved that RA/BMP-4 apoptosis signaling in WERI-Rb1 cells requires the RA receptor subtypes RARα, RARß, RXRß and RXRγ. Deciphering signaling mechanisms underlying apoptosis induction of RA and BMP-4 in WERI-Rb1 cells, our study provides useful starting-points for future retinoid-based therapy strategies in retinoblastoma.
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