1
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SIRT6 mediates MRTF-A deacetylation in vascular endothelial cells to antagonize oxLDL-induced ICAM-1 transcription. Cell Death Dis 2022; 8:96. [PMID: 35246513 PMCID: PMC8897425 DOI: 10.1038/s41420-022-00903-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 01/10/2022] [Accepted: 02/03/2022] [Indexed: 01/01/2023]
Abstract
Oxidized low-density lipoprotein (oxLDL), a known risk factor for atherosclerosis, activates the transcription of adhesion molecules (ICAM-1) in endothelial cells. We previously showed that myocardin-related transcription factor A (MRTF-A) mediates oxLDL-induced ICAM-1 transcription. Here we confirm that ICAM-1 transactivation paralleled dynamic alterations in MRTF-A acetylation. Since treatment with the antioxidant NAC dampened MRTF-A acetylation, MRTF-A acetylation appeared to be sensitive to cellular redox status. Of interest, silencing of SIRT6, a lysine deacetylase, restored MRTF-A acetylation despite the addition of NAC. SIRT6 directly interacted with MRTF-A to modulate MRTF-A acetylation. Deacetylation of MRTF-A by SIRT6 led to its nuclear expulsion thus dampening MRTF-A occupancy on the ICAM-1 promoter. Moreover, SIRT6 expression was downregulated with oxLDL stimulation likely owing to promoter hypermethylation in endothelial cells. DNA methyltransferase 1 (DNMT1) was recruited to the SIRT6 promoter and mediated SIRT6 repression. The ability of DNMT1 to repress SIRT6 promoter partly was dependent on ROS-sensitive serine 154 phosphorylation. In conclusion, our data unveil a novel DNMT1-SIRT6 axis that contributes to the regulation of MRTF-A acetylation and ICAM-1 transactivation in endothelial cells.
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2
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Sidorenko E, Sokolova M, Pennanen AP, Kyheröinen S, Posern G, Foisner R, Vartiainen MK. Lamina-associated polypeptide 2α is required for intranuclear MRTF-A activity. Sci Rep 2022; 12:2306. [PMID: 35145145 PMCID: PMC8831594 DOI: 10.1038/s41598-022-06135-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 01/18/2022] [Indexed: 12/16/2022] Open
Abstract
Myocardin-related transcription factor A (MRTF-A), a coactivator of serum response factor (SRF), regulates the expression of many cytoskeletal genes in response to cytoplasmic and nuclear actin dynamics. Here we describe a novel mechanism to regulate MRTF-A activity within the nucleus by showing that lamina-associated polypeptide 2α (Lap2α), the nucleoplasmic isoform of Lap2, is a direct binding partner of MRTF-A, and required for the efficient expression of MRTF-A/SRF target genes. Mechanistically, Lap2α is not required for MRTF-A nuclear localization, unlike most other MRTF-A regulators, but is required for efficient recruitment of MRTF-A to its target genes. This regulatory step takes place prior to MRTF-A chromatin binding, because Lap2α neither interacts with, nor specifically influences active histone marks on MRTF-A/SRF target genes. Phenotypically, Lap2α is required for serum-induced cell migration, and deregulated MRTF-A activity may also contribute to muscle and proliferation phenotypes associated with loss of Lap2α. Our studies therefore add another regulatory layer to the control of MRTF-A-SRF-mediated gene expression, and broaden the role of Lap2α in transcriptional regulation.
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Affiliation(s)
| | - Maria Sokolova
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Antti P Pennanen
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Salla Kyheröinen
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Guido Posern
- Institute for Physiological Chemistry, Medical Faculty, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Roland Foisner
- Max Perutz Labs, Center for Medical Biochemistry, Medical University of Vienna, Vienna Biocenter Campus (VBC), Vienna, Austria
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3
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Zhang Z, Chen B, Zhu Y, Zhang T, Yuan Y, Zhang X, Xu Y. The Jumonji Domain-Containing Histone Demethylase Homolog 1D/lysine Demethylase 7A (JHDM1D/KDM7A) Is an Epigenetic Activator of RHOJ Transcription in Breast Cancer Cells. Front Cell Dev Biol 2021; 9:664375. [PMID: 34249916 PMCID: PMC8262595 DOI: 10.3389/fcell.2021.664375] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 04/08/2021] [Indexed: 12/12/2022] Open
Abstract
The small GTPase RHOJ is a key regulator of breast cancer metastasis by promoting cell migration and invasion. The prometastatic stimulus TGF-β activates RHOJ transcription via megakaryocytic leukemia 1 (MKL1). The underlying epigenetic mechanism is not clear. Here, we report that MKL1 deficiency led to disrupted assembly of the RNA polymerase II preinitiation complex on the RHOJ promoter in breast cancer cells. This could be partially explained by histone H3K9/H3K27 methylation status. Further analysis confirmed that the H3K9/H3K27 dual demethylase JHDM1D/KDM7A was essential for TGF-β-induced RHOJ transcription in breast cancer cells. MKL1 interacted with and recruited KDM7A to the RHOJ promoter to cooperatively activate RHOJ transcription. KDM7A knockdown attenuated migration and invasion of breast cancer cells in vitro and mitigated the growth and metastasis of breast cancer cells in nude mice. KDM7A expression level, either singularly or in combination with that of RHOJ, could be used to predict prognosis in breast cancer patients. Of interest, KDM7A appeared to be a direct transcriptional target of TGF-β signaling. A SMAD2/SMAD4 complex bound to the KDM7A promoter and mediated TGF-β-induced KDM7A transcription. In conclusion, our data unveil a novel epigenetic mechanism whereby TGF-β regulates the transcription of the prometastatic small GTPase RHOJ. Screening for small-molecule inhibitors of KDM7A may yield effective therapeutic solutions to treat malignant breast cancers.
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Affiliation(s)
- Ziyu Zhang
- Key Laboratory of Women's Reproductive Health of Jiangxi, Jiangxi Provincial Maternal and Child Health Hospital, Nanchang, China.,Central Laboratory, Jiangxi Provincial Maternal and Child Health Hospital, Nanchang, China
| | - Baoyu Chen
- Key Laboratory of Targeted Invention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Yuwen Zhu
- Key Laboratory of Targeted Invention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Tianyi Zhang
- Key Laboratory of Targeted Invention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Yibiao Yuan
- Key Laboratory of Targeted Invention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Xiaoling Zhang
- School of Medicine, Nanchang University, Nanchang, China.,Department of Gynecology, Jiangxi Provincial Maternal and Child Health Hospital, Nanchang, China
| | - Yong Xu
- Key Laboratory of Targeted Invention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China
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4
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Miranda MZ, Lichner Z, Szászi K, Kapus A. MRTF: Basic Biology and Role in Kidney Disease. Int J Mol Sci 2021; 22:ijms22116040. [PMID: 34204945 PMCID: PMC8199744 DOI: 10.3390/ijms22116040] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/21/2021] [Accepted: 05/30/2021] [Indexed: 12/23/2022] Open
Abstract
A lesser known but crucially important downstream effect of Rho family GTPases is the regulation of gene expression. This major role is mediated via the cytoskeleton, the organization of which dictates the nucleocytoplasmic shuttling of a set of transcription factors. Central among these is myocardin-related transcription factor (MRTF), which upon actin polymerization translocates to the nucleus and binds to its cognate partner, serum response factor (SRF). The MRTF/SRF complex then drives a large cohort of genes involved in cytoskeleton remodeling, contractility, extracellular matrix organization and many other processes. Accordingly, MRTF, activated by a variety of mechanical and chemical stimuli, affects a plethora of functions with physiological and pathological relevance. These include cell motility, development, metabolism and thus metastasis formation, inflammatory responses and—predominantly-organ fibrosis. The aim of this review is twofold: to provide an up-to-date summary about the basic biology and regulation of this versatile transcriptional coactivator; and to highlight its principal involvement in the pathobiology of kidney disease. Acting through both direct transcriptional and epigenetic mechanisms, MRTF plays a key (yet not fully appreciated) role in the induction of a profibrotic epithelial phenotype (PEP) as well as in fibroblast-myofibroblast transition, prime pathomechanisms in chronic kidney disease and renal fibrosis.
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Affiliation(s)
- Maria Zena Miranda
- Keenan Research Centre for Biomedical Science of the St. Michael’s Hospital, Toronto, ON M5B 1W8, Canada; (M.Z.M.); (Z.L.); (K.S.)
| | - Zsuzsanna Lichner
- Keenan Research Centre for Biomedical Science of the St. Michael’s Hospital, Toronto, ON M5B 1W8, Canada; (M.Z.M.); (Z.L.); (K.S.)
| | - Katalin Szászi
- Keenan Research Centre for Biomedical Science of the St. Michael’s Hospital, Toronto, ON M5B 1W8, Canada; (M.Z.M.); (Z.L.); (K.S.)
- Department of Surgery, University of Toronto, Toronto, ON M5T 1P5, Canada
| | - András Kapus
- Keenan Research Centre for Biomedical Science of the St. Michael’s Hospital, Toronto, ON M5B 1W8, Canada; (M.Z.M.); (Z.L.); (K.S.)
- Department of Surgery, University of Toronto, Toronto, ON M5T 1P5, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
- Correspondence:
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5
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Li N, Liu S, Zhang Y, Yu L, Hu Y, Wu T, Fang M, Xu Y. Transcriptional Activation of Matricellular Protein Spondin2 (SPON2) by BRG1 in Vascular Endothelial Cells Promotes Macrophage Chemotaxis. Front Cell Dev Biol 2020; 8:794. [PMID: 32974343 PMCID: PMC7461951 DOI: 10.3389/fcell.2020.00794] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 07/28/2020] [Indexed: 12/18/2022] Open
Abstract
The matricellular protein SPON2 plays diverse roles in the development of cardiovascular diseases. SPON2 is expressed in endothelial cells, but its transcription regulation in the context of atherogenesis remains incompletely appreciated. Here we report that SPON2 expression was up-regulated by pro-atherogenic stimuli (oxLDL and TNF-α) in vascular endothelia cells. In addition, endothelial SPON2 was elevated in Apoe–/– mice fed on a Western diet compared to the control mice. Induction of SPON2 in endothelial cells by pro-atherogenic stimuli was mediated by BRG1, a chromatin remodeling protein, both in vitro and in vivo. Further analysis revealed that BRG1 interacted with the sequence-specific transcription factor Egr-1 to activate SPON2 transcription. BRG1 contributed to SPON2 trans-activation by modulating chromatin structure surrounding the SPON2 promoter. Functionally, activation of SPON2 transcription by the Egr-1/BRG1 complex provided chemoattractive cues for macrophage trafficking. SPON2 depletion abrogated the ability of BRG1 or Egr-1 to stimulate endothelial derived chemoattractive cue for macrophage migration. On the contrary, recombinant SPON2 rescued endothelial chemo-attractability in the absence of BRG1 or Egr-1. In conclusion, our data have identified a novel transcriptional cascade in endothelial cells that may potentially promote macrophage recruitment and vascular inflammation leading to atherogenesis.
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Affiliation(s)
- Nan Li
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Shuai Liu
- Hainan Provincial Key Laboratory for Tropical Cardiovascular Diseases Research and Key Laboratory of Emergency and Trauma of Ministry of Education, Institute of Cardiovascular Research of the First Affiliated Hospital, Hainan Medical University, Haikou, China.,Department of Cardiology, Kaifeng People's Hospital, Kaifeng, China
| | - Yuanyuan Zhang
- Institute of Biomedical Research, Liaocheng University, Liaocheng, China
| | - Liming Yu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Yanjiang Hu
- Department of Cardiothoracic Surgery, Liyang People's Hospital, Liyang, China
| | - Teng Wu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Mingming Fang
- Department of Clinical Medicine and Laboratory Center for Experimental Medicine, Jiangsu Health Vocational Institute, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China
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6
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Yang Y, Yang G, Yu L, Lin L, Liu L, Fang M, Xu Y. An Interplay Between MRTF-A and the Histone Acetyltransferase TIP60 Mediates Hypoxia-Reoxygenation Induced iNOS Transcription in Macrophages. Front Cell Dev Biol 2020; 8:484. [PMID: 32626711 PMCID: PMC7315810 DOI: 10.3389/fcell.2020.00484] [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: 10/06/2019] [Accepted: 05/22/2020] [Indexed: 01/23/2023] Open
Abstract
Cardiac ischemia-reperfusion injury (IRI) represents a major pathophysiological event associated with permanent loss of heart function. Several inter-dependent processes contribute to cardiac IRI that include accumulation of reactive oxygen species (ROS), aberrant inflammatory response, and depletion of energy supply. Inducible nitric oxide synthase (iNOS) is a pro-inflammatory mediator and a major catalyst of ROS generation. In the present study we investigated the epigenetic mechanism whereby iNOS transcription is up-regulated in macrophages in the context of cardiac IRI. We report that germline deletion or systemic inhibition of myocardin-related transcription factor A (MRTF-A) in mice attenuated up-regulation of iNOS following cardiac IRI in the heart. In cultured macrophages, depletion or inhibition of MRTF-A suppressed iNOS induction by hypoxia-reoxygenation (HR). In contrast, MRTF-A over-expression potentiated activation of the iNOS promoter by HR. MRTF-A directly binds to the iNOS promoter in response to HR stimulation. MRTF-A binding to the iNOS promoter was synonymous with active histone modifications including trimethylated H3K4, acetylated H3K9, H3K27, and H4K16. Further analysis revealed that MRTF-A interacted with H4K16 acetyltransferase TIP60 to synergistically activate iNOS transcription. TIP60 depletion or inhibition achieved equivalent effects as MRTF-A depletion/inhibition in terms of iNOS repression. Of interest, TIP60 appeared to form a crosstalk with the H3K4 trimethyltransferase complex to promote iNOS trans-activation. In conclusion, we data suggest that the MRTF-A-TIP60 axis may play a critical role in iNOS transcription in macrophages and as such be considered as a potential target for the intervention of cardiac IRI.
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Affiliation(s)
- Yuyu Yang
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China.,Key Laboratory of Emergency and Trauma of Ministry of Education, Institute of Cardiovascular Research of the First Affiliated Hospital, Hainan Medical University, Haikou, China
| | - Guang Yang
- Department of Pathology, Soochow Municipal Hospital Affiliated with Nanjing Medical University, Soochow, China
| | - Liming Yu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Disease, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Ling Lin
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Li Liu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Disease, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Mingming Fang
- Center for Experimental Medicine, Jiangsu Health Vocational College, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China
| | - Yong Xu
- Institute of Biomedical Research, Liaocheng University, Liaocheng, China.,Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Disease, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
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7
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Mao L, Liu L, Zhang T, Qin H, Wu X, Xu Y. Histone Deacetylase 11 Contributes to Renal Fibrosis by Repressing KLF15 Transcription. Front Cell Dev Biol 2020; 8:235. [PMID: 32363192 PMCID: PMC7180197 DOI: 10.3389/fcell.2020.00235] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 03/20/2020] [Indexed: 12/12/2022] Open
Abstract
Renal fibrosis represents a key pathophysiological process in patients with chronic kidney diseases (CKD) and is typically associated with a poor prognosis. Renal tubular epithelial cells (RTECs), in response to a host of pro-fibrogenic stimuli, can trans-differentiate into myofibroblast-like cells and produce extracellular matrix proteins to promote renal fibrosis. In the present study we investigated the role of histone deacetylase 11 (HDAC11) in this process and the underlying mechanism. We report that expression levels of HDAC11 were up-regulated in the kidneys in several different animal models of renal fibrosis. HDAC11 was also up-regulated by treatment of Angiotensin II (Ang II) in cultured RTECs. Consistently, pharmaceutical inhibition with a small-molecule inhibitor of HDAC11 (quisinostat) attenuated unilateral ureteral obstruction (UUO) induced renal fibrosis in mice. Similarly, HDAC11 inhibition by quisinostat or HDAC11 depletion by siRNA blocked Ang II induced pro-fibrogenic response in cultured RTECs. Mechanistically, HDAC11 interacted with activator protein 2 (AP-2α) to repress the transcription of Kruppel-like factor 15 (KLF15). In accordance, KLF15 knockdown antagonized the effect of HDAC11 inhibition or depletion and enabled Ang II to promote fibrogenesis in RTECs. Therefore, we data unveil a novel AP-2α-HDAC11-KLF15 axis that contributes to renal fibrosis.
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Affiliation(s)
- Lei Mao
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Li Liu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Tao Zhang
- Department of Geriatric Nephrology, Jiangsu Province Hospital, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Hao Qin
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Xiaoyan Wu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China.,The Laboratory Center for Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China
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8
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Lv F, Li N, Kong M, Wu J, Fan Z, Miao D, Xu Y, Ye Q, Wang Y. CDKN2a/p16 Antagonizes Hepatic Stellate Cell Activation and Liver Fibrosis by Modulating ROS Levels. Front Cell Dev Biol 2020; 8:176. [PMID: 32266258 PMCID: PMC7105638 DOI: 10.3389/fcell.2020.00176] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 03/03/2020] [Indexed: 12/31/2022] Open
Abstract
The lipid-storage hepatic stellate cells (HSC) play as pivotal role in liver fibrosis being able to trans-differentiate into myofibroblasts in response to various pro-fibrogenic stimuli. In the present study we investigated the role of CDKN2a/p16, a negative regulator of cell cycling, in HSC activation and the underlying mechanism. Levels of p16 were significantly down-regulated in activated HSCs isolated from mice induced to develop liver fibrosis compared to quiescent HSCs isolated from the control mice ex vivo. There was a similar decrease in p16 expression in cultured HSCs undergoing spontaneous activation or exposed to TGF-β treatment in vitro. More important, p16 down-regulation was observed to correlate with cirrhosis in humans. In a classic model of carbon tetrachloride (CCl4) induced liver fibrosis, fibrogenesis was far more extensive in mice with p16 deficiency (KO) than the wild type (WT) littermates. Depletion of p16 in cultured HSCs promoted the synthesis of extracellular matrix (ECM) proteins. Mechanistically, p16 deficiency accelerated reactive oxygen species (ROS) generation in HSCs likely through the p38 MAPK signaling. P38 inhibition or ROS cleansing attenuated ECM production in p16 deficient HSCs. Taken together, our data unveil a previously unappreciated role for p16 in the regulation of HSC activation. Screening for small-molecule compounds that can boost p16 activity may yield novel therapeutic strategies against liver fibrosis.
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Affiliation(s)
- Fangqiao Lv
- Department of Cell Biology, Municipal Laboratory for Liver Protection and Regulation of Regeneration, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Nan Li
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Ming Kong
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Jun Wu
- Department of Anatomy, Nanjing Medical University, Nanjing, China
| | - Zhiwen Fan
- Department of Pathology, The Affiliated Drum Tower Hospital, Nanjing University Medical School, Nanjing, China
| | - Dengshun Miao
- Department of Anatomy, Nanjing Medical University, Nanjing, China
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China
| | - Qing Ye
- Department of Pathology, The Affiliated Drum Tower Hospital, Nanjing University Medical School, Nanjing, China
| | - Yutong Wang
- Department of Cell Biology, Municipal Laboratory for Liver Protection and Regulation of Regeneration, School of Basic Medical Sciences, Capital Medical University, Beijing, China
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9
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Li Z, Xu Y. Response by Li and Xu to Letter Regarding Article, "Megakaryocytic Leukemia 1 Bridges Epigenetic Activation of NADPH Oxidase in Macrophages to Cardiac Ischemia-Reperfusion Injury". Circulation 2020; 139:e965-e966. [PMID: 31082295 DOI: 10.1161/circulationaha.119.040160] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Zilong Li
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Disease, Department of Pathophysiology, Nanjing Medical University, China (Z.L., Y.X.).,Institute of Biomedical Research, Liaocheng University, China (Z.L., Y.X.)
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Disease, Department of Pathophysiology, Nanjing Medical University, China (Z.L., Y.X.).,Institute of Biomedical Research, Liaocheng University, China (Z.L., Y.X.)
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10
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Deacetylation of MRTF-A by SIRT1 defies senescence induced down-regulation of collagen type I in fibroblast cells. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165723. [PMID: 32061777 DOI: 10.1016/j.bbadis.2020.165723] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 01/13/2020] [Accepted: 02/10/2020] [Indexed: 12/21/2022]
Abstract
Aging provokes both morphological and functional changes in cells, which are accompanied by a fundamental shift in gene expression patterns. One of the characteristic alterations associated with senescence in fibroblast cells is the down-regulation of collagen type I genes. In the present study, we investigated the contribution of myocardin-related transcription factor A, or MRTF-A, in this process. In mouse embryonic fibroblast (MEF) cells and human foreskin fibroblast (HFF) cells, senescence, induced by either progressive passage or treatment with hydrogen peroxide (H2O2), led to augmented lysine acetylation of MRTF-A paralleling down-regulation of collagen type I and SIRT1, a lysine deacetylase. SIRT1 interacted with MRTF-A to promote MRTF-A deacetylation. SIRT1 over-expression or activation by selective agonists enhanced trans-activation of the collagen promoters by MRTF-A. On the contrary, SIRT1 depletion or inhibition by specific antagonists suppressed trans-activation of the collagen promoters by MRTF-A. Likewise, mutation of four lysine residues within MRTF-A rendered it more potent in terms of activating the collagen promoters but unresponsive to SIRT1. Importantly, SIRT1 activation in senescent fibroblasts mitigated repression of collagen type I expression whereas SIRT1 inhibition promoted the loss of collagen type I expression prematurely in young fibroblasts. Mechanistically, SIRT1 enhanced the affinity of MRTF-A for the collagen type I promoters. In conclusion, our data unveil a novel mechanism that underscores aging-associated loss of collagen type I in fibroblasts via SIRT1-mediated post-translational modification of MRTF-A.
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11
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MKL1 promotes endothelial-to-mesenchymal transition and liver fibrosis by activating TWIST1 transcription. Cell Death Dis 2019; 10:899. [PMID: 31776330 PMCID: PMC6881349 DOI: 10.1038/s41419-019-2101-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 10/21/2019] [Accepted: 10/29/2019] [Indexed: 12/11/2022]
Abstract
Excessive fibrogenic response in the liver disrupts normal hepatic anatomy and function heralding such end-stage liver diseases as hepatocellular carcinoma and cirrhosis. Sinusoidal endothelial cells contribute to myofibroblast activation and liver fibrosis by undergoing endothelial-mesenchymal transition (EndMT). The underlying mechanism remains poorly defined. Here we report that inhibition or endothelial-specific deletion of MKL1, a transcriptional modulator, attenuated liver fibrosis in mice. MKL1 inhibition or deletion suppressed EndMT induced by TGF-β. Mechanistically, MKL1 was recruited to the promoter region of TWIST1, a master regulator of EndMT, and activated TWIST1 transcription in a STAT3-dependent manner. A small-molecule STAT3 inhibitor (C188-9) alleviated EndMT in cultured cells and bile duct ligation (BDL) induced liver fibrosis in mice. Finally, direct inhibition of TWIST1 by a small-molecule compound harmine was paralleled by blockade of EndMT in cultured cells and liver fibrosis in mice. In conclusion, our data unveil a novel mechanism underlying EndMT and liver fibrosis and highlight the possibility of targeting the STAT3-MKL1-TWIST1 axis in the intervention of aberrant liver fibrogenesis.
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12
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Li Z, Lv F, Dai C, Wang Q, Jiang C, Fang M, Xu Y. Activation of Galectin-3 (LGALS3) Transcription by Injurious Stimuli in the Liver Is Commonly Mediated by BRG1. Front Cell Dev Biol 2019; 7:310. [PMID: 31850346 PMCID: PMC6901944 DOI: 10.3389/fcell.2019.00310] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 11/13/2019] [Indexed: 01/13/2023] Open
Abstract
Galectin-3 (encoded by LGALS3) is a glycan-binding protein that regulates a diverse range of pathophysiological processes contributing to the pathogenesis of human diseases. Previous studies have found that galectin-3 levels are up-regulated in the liver by a host of different injurious stimuli. The underlying epigenetic mechanism, however, is unclear. Here we report that conditional knockout of Brahma related gene (BRG1), a chromatin remodeling protein, in hepatocytes attenuated induction of galectin-3 expression in several different animal models of liver injury. Similarly, BRG1 depletion or pharmaceutical inhibition in cultured hepatocytes suppressed the induction of galectin-3 expression by treatment with LPS plus free fatty acid (palmitate). Further analysis revealed that BRG1 interacted with AP-1 to bind to the proximal galectin-3 promoter and activate transcription. Mechanistically, DNA demethylation surrounding the galectin-3 promoter appeared to be a rate-limiting step in BRG1-mediated activation of galectin-3 transcription. BRG1 recruited the DNA 5-methylcytosine dioxygenase TET1 to the galectin-3 to promote active DNA demethylation thereby activating galectin-3 transcription. Finally, TET1 silencing abrogated induction of galectin-3 expression by LPS plus palmitate in cultured hepatocytes. In conclusion, our data unveil a novel epigenetic pathway that contributes to injury-associated activation of galectin-3 transcription in hepatocytes.
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Affiliation(s)
- Zilong Li
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Fangqiao Lv
- Department of Cell Biology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Congxin Dai
- Department of Neurosurgery, Peking Union Medical College Hospital, Beijing, China
| | - Qiong Wang
- Department of Surgical Oncology, the Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Traditional Chinese Medicine, Nanjing, China
| | - Chao Jiang
- Department of Surgical Oncology, the Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Traditional Chinese Medicine, Nanjing, China
| | - Mingming Fang
- Department of Clinical Medicine, Laboratory Center for Basic Medical Sciences, Jiangsu Health Vocational College, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China
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13
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Epigenetic activation of CTGF transcription by high glucose in renal tubular epithelial cells is mediated by myocardin-related transcription factor A. Cell Tissue Res 2019; 379:549-559. [PMID: 31773302 DOI: 10.1007/s00441-019-03124-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 10/09/2019] [Indexed: 01/26/2023]
Abstract
Diabetic nephropathy (DN) is one of the most devastating complications of diabetes. Connective tissue growth factor (CTGF) levels are up-regulated in patients with DN and in renal tubular epithelial cells (RTECs) exposed to high glucose (HG). The underlying epigenetic mechanism remains to be elucidated. In the present study, we investigate the role of myocardin-related transcription factor A (MRTF-A) in HG-induced CTGF transcription in RTECs. We report that in two different animal models of DN, one induced by streptozotocin (STZ) injection and the other induced by high-fat diet (HFD) feeding, MRTF-A deficiency attenuated CTGF induction in the kidneys. In cultured RTECs, MRTF-A knockdown similarly ameliorated CTGF induction by HG treatment. Upon CTGF induction, there was an increase in acetylated histone H3 (AcH3) and trimethylated H3K4 (H3K4Me3) on the CTGF promoter region accompanying a decrease in dimethylated H3K9 (H3K9Me2). MRTF-A ablation in vivo or depletion in vitro comparably dampened the accumulation of AcH3 and H3K4Me3 but restored H3K9Me2 on the CTGF promoter. Further analyses revealed that MRTF-A interacted with and recruited histone demethylase KDM3A to the CTGF promoter to activate transcription. KDM3A silencing equivalently weakened HG-induced CTGF induction in RTECs. In conclusion, MRTF-A contributes to HG-induced CTGF transcription via an epigenetic mechanism.
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14
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Li Z, Xia J, Fang M, Xu Y. Epigenetic regulation of lung cancer cell proliferation and migration by the chromatin remodeling protein BRG1. Oncogenesis 2019; 8:66. [PMID: 31695026 PMCID: PMC6834663 DOI: 10.1038/s41389-019-0174-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 10/14/2019] [Accepted: 10/15/2019] [Indexed: 01/10/2023] Open
Abstract
Malignant lung cancer cells are characterized by uncontrolled proliferation and migration. Aberrant lung cancer cell proliferation and migration are programmed by altered cancer transcriptome. The underlying epigenetic mechanism is unclear. Here we report that expression levels of BRG1, a chromatin remodeling protein, were significantly up-regulated in human lung cancer biopsy specimens of higher malignancy grades compared to those of lower grades. Small interfering RNA mediated depletion or pharmaceutical inhibition of BRG1 suppressed proliferation and migration of lung cancer cells. BRG1 depletion or inhibition was paralleled by down-regulation of cyclin B1 (CCNB1) and latent TGF-β binding protein 2 (LTBP2) in lung cancer cells. Further analysis revealed that BRG1 directly bound to the CCNB1 promoter to activate transcription in response to hypoxia stimulation by interacting with E2F1. On the other hand, BRG1 interacted with Sp1 to activate LTBP2 transcription. Mechanistically, BRG1 regulated CCNB1 and LTBP2 transcription by altering histone modifications on target promoters. Specifically, BRG1 recruited KDM3A, a histone H3K9 demethylase, to remove dimethyl H3K9 from target gene promoters thereby activating transcription. KDM3A knockdown achieved equivalent effects as BRG1 silencing by diminishing lung cancer proliferation and migration. Of interest, BRG1 directly activated KDM3A transcription by forming a complex with HIF-1α. In conclusion, our data unveil a novel epigenetic mechanism whereby malignant lung cancer cells acquired heightened ability to proliferate and migrate. Targeting BRG1 may yield effective interventional strategies against malignant lung cancers.
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Affiliation(s)
- Zilong Li
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Jun Xia
- Department of Respiratory Medicine, The Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Traditional Chinese Medicine, Nanjing, China.
| | - Mingming Fang
- Department of Clinical Medicine and Laboratory Center for Experimental Medicine, Jiangsu Health Vocational College, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China. .,Institute of Biomedical Research, Liaocheng University, Liaocheng, China.
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15
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Mao L, Liu L, Zhang T, Wu X, Zhang T, Xu Y. MKL1 mediates TGF-β-induced CTGF transcription to promote renal fibrosis. J Cell Physiol 2019; 235:4790-4803. [PMID: 31637729 DOI: 10.1002/jcp.29356] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 09/30/2019] [Indexed: 12/20/2022]
Abstract
Aberrant fibrogenesis impairs the architectural and functional homeostasis of the kidneys. It also predicts poor diagnosis in patients with end-stage renal disease (ESRD). Renal tubular epithelial cells (RTEC) can trans-differentiate into myofibroblasts to produce extracellular matrix proteins and contribute to renal fibrosis. Connective tissue growth factor (CTGF) is a cytokine upregulated in RTECs during renal fibrosis. In the present study, we investigated the regulation of CTGF transcription by megakaryocytic leukemia 1 (MKL1). Genetic deletion or pharmaceutical inhibition of MKL1 in mice mitigated renal fibrosis following the unilateral ureteral obstruction procedure. Notably, MKL1 deficiency in mice downregulated CTGF expression in the kidneys. Likewise, MKL1 knockdown or inhibition in RTEs blunted TGF-β induced CTGF expression. Further, it was discovered that MKL1 bound directly to the CTGF promoter by interacting with SMAD3 to activate CTGF transcription. In addition, MKL1 mediated the interplay between p300 and WDR5 to regulate CTGF transcription. CTGF knockdown dampened TGF-β induced pro-fibrogenic response in RTEs. MKL1 activity was reciprocally regulated by CTGF. In conclusion, we propose that targeting the MKL1-CTGF axis may generate novel therapeutic solutions against aberrant renal fibrogenesis.
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Affiliation(s)
- Lei Mao
- Department of Pathophysiology, Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Nanjing Medical University, Nanjing, China
| | - Li Liu
- Department of Pathophysiology, Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Nanjing Medical University, Nanjing, China
| | - Tianyi Zhang
- Department of Pathophysiology, Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Nanjing Medical University, Nanjing, China
| | - Xiaoyan Wu
- Department of Pathophysiology, Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Nanjing Medical University, Nanjing, China.,The Laboratory Center for Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Tao Zhang
- Department of Geriatric Nephrology, Jiangsu Province Hospital, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yong Xu
- Department of Pathophysiology, Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Nanjing Medical University, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China
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16
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Shao J, Xu Y, Fang M. BRG1 deficiency in endothelial cells alleviates thioacetamide induced liver fibrosis in mice. Biochem Biophys Res Commun 2019; 521:212-219. [PMID: 31635808 DOI: 10.1016/j.bbrc.2019.10.109] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 10/12/2019] [Indexed: 12/11/2022]
Abstract
Liver sinusoidal endothelial cells play a key role maintaining the hepatic homeostasis, the disruption of which is associated with such end-stage liver diseases as hepatocellular carcinoma and cirrhosis. In the present study we investigated the role of brahma-related gene 1 (BRG1), a chromatin remodeling protein, in regulating endothelial transcription and the implication in liver fibrosis. We report that endothelial-specific deletion of BRG1 in mice attenuated liver fibrosis induced by injection with thioacetamide (TAA). Coincidently, alleviation of liver fibrosis as a result of endothelial BRG1 deletion was accompanied by an up-regulation of eNOS activity and NO bioavailability. In cultured endothelial cells, exposure to lipopolysaccharide (LPS) suppressed eNOS activity whereas BRG1 depletion with small interfering RNA restored eNOS-dependent NO production. Further analysis revealed that BRG1 was recruited to the caveolin-1 (CAV1) promoter by Sp1 and activated transcription of CAV1, which in turn inhibited eNOS activity. Mechanistically, BRG1 interacted with the H3K4 trimethyltransferase MLL1 to modulate H3K4 trimethylation surrounding the CAV1 promoter thereby contributing to LPS-induced CAV1 activation. In conclusion, our data unveil a novel role for BRG1 in the regulation of endothelial function and liver fibrosis.
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Affiliation(s)
- Jing Shao
- Wuxi School of Medicine, Jiangnan University, Wuxi, China
| | - Yong Xu
- Institute of Biomedical Research, Liaocheng University, Liaocheng, China
| | - Mingming Fang
- Department of Clinical Medicine and Center for Experimental Medicine, Jiangsu Health Vocational College, Nanjing, China; Institute of Biomedical Research, Liaocheng University, Liaocheng, China.
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17
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Lu Y, Lv F, Kong M, Chen X, Duan Y, Chen X, Sun D, Fang M, Xu Y. A cAbl-MRTF-A Feedback Loop Contributes to Hepatic Stellate Cell Activation. Front Cell Dev Biol 2019; 7:243. [PMID: 31681772 PMCID: PMC6805704 DOI: 10.3389/fcell.2019.00243] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 10/03/2019] [Indexed: 12/13/2022] Open
Abstract
Trans-differentiation of quiescent hepatic stellate cells (HSC) to myofibroblasts is a hallmark event in liver fibrosis. Previous studies have led to the discovery that myocardin-related transcription factor A (MRTF-A) is a key regulator of HSC trans-differentiation or, activation. In the present study we investigated the interplay between MRTF-A and c-Abl (encoded by Abl1), a tyrosine kinase, in this process. We report that hepatic expression levels of c-Abl were down-regulated in MRTF-A knockout (KO) mice compared to wild type (WT) littermates in several different models of liver fibrosis. MRTF-A deficiency also resulted in c-Abl down-regulation in freshly isolated HSCs from the fibrotic livers of mice. MRTF-A knockdown or inhibition repressed c-Abl in cultured HSCs in vitro. Further analyses revealed that MRTF-A directly bound to the Abl1 promoter to activate transcription by interacting with Sp1. Reciprocally, pharmaceutical inhibition of c-Abl suppressed MRTF-A activity. Mechanistically, c-Abl activated extracellular signal-regulated kinase (ERK), which in turn phosphorylated MRTF-A and promoted MRTF-A nuclear trans-localization. In conclusion, our data suggest that a c-Abl-MRTF-A positive feedback loop contributes to HSC activation and liver fibrosis.
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Affiliation(s)
- Yunjie Lu
- Department of Hepatobiliary and Pancreatic Surgery, The First People's Hospital of Changzhou, The Third Affiliated Hospital of Soochow University, Changzhou, China
| | - Fangqiao Lv
- Department of Cell Biology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Ming Kong
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Xuyang Chen
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Yunfei Duan
- Department of Hepatobiliary and Pancreatic Surgery, The First People's Hospital of Changzhou, The Third Affiliated Hospital of Soochow University, Changzhou, China
| | - Xuemin Chen
- Department of Hepatobiliary and Pancreatic Surgery, The First People's Hospital of Changzhou, The Third Affiliated Hospital of Soochow University, Changzhou, China
| | - Donglin Sun
- Department of Hepatobiliary and Pancreatic Surgery, The First People's Hospital of Changzhou, The Third Affiliated Hospital of Soochow University, Changzhou, China
| | - Mingming Fang
- Institute of Biomedical Research, Liaocheng University, Liaocheng, China.,Department of Clinical Medicine and Laboratory Center for Experimental Medicine, Jiangsu Vocational College of Medicine, Nanjing, China
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China
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18
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Wu X, Fan Z, Chen M, Chen Y, Rong D, Cui Z, Yuan Y, Zhuo L, Xu Y. Forkhead transcription factor FOXO3a mediates interferon-γ-induced MHC II transcription in macrophages. Immunology 2019; 158:304-313. [PMID: 31509237 DOI: 10.1111/imm.13116] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 08/23/2019] [Accepted: 09/03/2019] [Indexed: 12/23/2022] Open
Abstract
Macrophages are professional antigen-presenting cells relying on the expression of class II major histocompatibility complex (MHC II) genes. Interferon-γ (IFN-γ) activates MHC II transcription via the assembly of an enhanceosome centred on class II trans-activator (CIITA). In the present study, we investigated the role of the forkhead transcription factor FOXO3a in IFN- γ-induced MHC II transcription in macrophages. Knockdown of FOXO3a, but not FOXO1 or FOXO4, diminished IFN-γ-induced MHC II expression in RAW cells. On the contrary, over-expression of FOXO3a, but neither FOXO1 nor FOXO4, enhanced CIITA-mediated trans-activation of the MHC II promoter. IFN-γ treatment promoted the recruitment of FOXO3a to the MHC II promoter. Co-immunoprecipitation and RE-ChIP assays showed that FOXO3a was a component of the MHC II enhanceosome forming interactions with CIITA, RFX5, RFXB and RFXAP. FOXO3a contributed to MHC II transcription by altering histone modifications surrounding the MHC II promoter. Of interest, FOXO3a was recruited to the type IV CIITA promoter and directly activated CIITA transcription by interacting with signal transducer of activation and transcription 1 in response to IFN-γ stimulation. In conclusion, our data unveil a novel role for FOXO3a in the regulation of MHC II transcription in macrophages.
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Affiliation(s)
- Xiaoyan Wu
- The Laboratory Centre for Basic Medical Sciences, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China.,Department of Pathophysiology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Zhiwen Fan
- Department of Pathology, Nanjing Drum Tower Hospital Affiliated with Nanjing University School of Medicine, Nanjing, China
| | - Ming Chen
- The Laboratory Centre for Basic Medical Sciences, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Yi Chen
- The Laboratory Centre for Basic Medical Sciences, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Danyan Rong
- The Laboratory Centre for Basic Medical Sciences, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Zhiwei Cui
- The Laboratory Centre for Basic Medical Sciences, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Yibiao Yuan
- The Laboratory Centre for Basic Medical Sciences, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Lili Zhuo
- Department of Geriatrics, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yong Xu
- Institute of Biomedical Research, Liaocheng University, Liaocheng, China.,Department of Pathophysiology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
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19
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Cheng X, Xu S, Pan J, Zheng J, Wang X, Yu H, Bao J, Xu Y, Guan H, Zhang L. MKL1 overexpression predicts poor prognosis in patients with papillary thyroid cancer and promotes nodal metastasis. J Cell Sci 2019; 132:jcs.231399. [PMID: 31363007 DOI: 10.1242/jcs.231399] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 07/19/2019] [Indexed: 12/20/2022] Open
Abstract
Papillary thyroid cancer (PTC), the most common thyroid malignancy, has a strong propensity for cervical lymph node metastasis (LNM), which increases the risk of locoregional recurrence and decreases survival probability in some high-risk groups. Hence, there is a pressing requirement for a reliable biomarker to predict LNM in thyroid cancer. In the present study, MKL1 (also known as MRTFA) expression was significantly increased in PTC patients with LNM compared with those without. Further receiver operating characteristic (ROC) analysis showed that MKL1 expression had a diagnostic value in the differentiation of LNM in PTC. Furthermore, Kaplan-Meier analysis revealed that high MKL1 expression was associated with significantly decreased survival in PTC. Additionally, our study indicated that MKL1 promoted the migration and invasion of PTC cells. MKL1 interacted with and recruited Smad3 to the promoter of MMP2 to activate MMP2 transcription upon treatment with TGF-β. Moreover, there was significant correlation between expression of TGF-β, MKL1 and MMP2 in our clinical cohort of specimens from individuals with PTC. Our results suggest that the detection of MKL1 expression could be used to predict cervical LNM and inform post-operative follow-up in individuals with PTC.
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Affiliation(s)
- Xian Cheng
- Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, Jiangsu, China
| | - Shichen Xu
- Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, Jiangsu, China
| | - Jie Pan
- Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, Jiangsu, China.,State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214000, Jiangsu, China
| | - Jiangxia Zheng
- Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, Jiangsu, China.,State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214000, Jiangsu, China
| | - Xiaowen Wang
- Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, Jiangsu, China.,State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214000, Jiangsu, China
| | - Huixin Yu
- Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, Jiangsu, China
| | - Jiandong Bao
- Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, Jiangsu, China
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing 211100, China
| | - Haixia Guan
- Department of Endocrinology & Metabolism and Institute of Endocrinology, the First Hospital of China Medical University, Shenyang, Liaoning 110000, China
| | - Li Zhang
- Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, Jiangsu, China
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20
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Kong M, Chen X, Lv F, Ren H, Fan Z, Qin H, Yu L, Shi X, Xu Y. Serum response factor (SRF) promotes ROS generation and hepatic stellate cell activation by epigenetically stimulating NCF1/2 transcription. Redox Biol 2019; 26:101302. [PMID: 31442911 PMCID: PMC6831835 DOI: 10.1016/j.redox.2019.101302] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 08/13/2019] [Accepted: 08/15/2019] [Indexed: 12/25/2022] Open
Abstract
Activation of hepatic stellate cells (HSC) is a hallmark event in liver fibrosis. Accumulation of reactive oxygen species (ROS) serves as a driving force for HSC activation. The regulatory subunits of the NOX complex, NCF1 (p47phox) and NCF2 (p67phox), are up-regulated during HSC activation contributing to ROS production and liver fibrosis. The transcriptional mechanism underlying NCF1/2 up-regulation is not clear. In the present study we investigated the role of serum response factor (SRF) in HSC activation focusing on the transcriptional regulation of NCF1/2. We report that compared to wild type littermates HSC-conditional SRF knockout (CKO) mice exhibited a mortified phenotype of liver fibrosis induced by thioacetamide (TAA) injection or feeding with a methionine-and-choline deficient diet (MCD). More importantly, SRF deletion attenuated ROS levels in HSCs in vivo. Similarly, SRF knockdown in cultured HSCs suppressed ROS production in vitro. Further analysis revealed that SRF deficiency resulted in repression of NCF1/NCF2 expression. Mechanistically, SRF regulated epigenetic transcriptional activation of NCF1/NCF2 by interacting with and recruiting the histone acetyltransferase KAT8 during HSC activation. In conclusion, we propose that SRF integrates transcriptional activation of NCF1/NCF2 and ROS production to promote liver fibrosis.
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Affiliation(s)
- Ming Kong
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Pathophysiology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Xuyang Chen
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Pathophysiology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Fangqiao Lv
- Department of Cell Biology and the Municipal Laboratory of Liver Protection and Regulation of Regeneration, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Haozhen Ren
- Department of Hepato-biliary Surgery and Department of Pathology, Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing, China
| | - Zhiwen Fan
- Department of Hepato-biliary Surgery and Department of Pathology, Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing, China
| | - Hao Qin
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Pathophysiology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Liming Yu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Pathophysiology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Xiaolei Shi
- Department of Hepato-biliary Surgery and Department of Pathology, Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing, China.
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Pathophysiology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China; Institute of Biomedical Research, Liaocheng University, Liaocheng, China.
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21
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Fan Z, Li N, Xu Z, Wu J, Fan X, Xu Y. An interaction between MKL1, BRG1, and C/EBPβ mediates palmitate induced CRP transcription in hepatocytes. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2019; 1862:194412. [PMID: 31356989 DOI: 10.1016/j.bbagrm.2019.194412] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 07/22/2019] [Accepted: 07/23/2019] [Indexed: 12/11/2022]
Abstract
Non-alcoholic steatohepatitis (NASH) is one of the most predominant disorders in metabolic syndrome. Induction of pro-inflammatory mediators in hepatocytes exposed to free fatty acids represents a hallmark event during NASH pathogenesis. C-reactive protein (CRP) is a prototypical pro-inflammatory mediator. In the present study, we investigated the mechanism by which megakaryocytic leukemia 1 (MKL1) mediates palmitate (PA) induced CRP transcription in hepatocytes. We report that over-expression of MKL1, but not MKL2, activated the CRP promoter whereas depletion or inhibition of MKL1 repressed the CRP promoter. MKL1 potentiated the induction of the CRP promoter activity by PA treatment. Importantly, MKL1 knockdown by siRNA or pharmaceutical inhibition by CCG-1423 attenuated the induction of endogenous CRP expression in hepatocytes. Similarly, primary hepatocytes isolated from wild type (WT) mice produced more CRP than those isolated from MKL1 deficient (KO) mice when stimulated with PA. Mechanistically, the sequence-specific transcription factor CCAAT-enhancer-binding protein (C/EBPβ) interacted with MKL1 and recruited MKL1 to activate CRP transcription. Reciprocally, MKL1 modulated C/EBPβ activity by recruiting the chromatin remodeling protein BRG1 to the CRP promoter to alter histone modifications. In conclusion, our data delineate a novel epigenetic mechanism underlying augmented hepatic inflammation during NASH pathogenesis.
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Affiliation(s)
- Zhiwen Fan
- Department of Pathology, Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing, China
| | - Nan Li
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Zheng Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Jiahao Wu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Xiangshan Fan
- Department of Pathology, Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing, China.
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China; Institute of Biomedical Research, Liaocheng University, Liaocheng, China.
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Liu L, Mao L, Xu Y, Wu X. Endothelial-specific deletion of Brahma-related gene 1 (BRG1) assuages unilateral ureteral obstruction induced renal injury in mice. Biochem Biophys Res Commun 2019; 517:244-252. [PMID: 31349970 DOI: 10.1016/j.bbrc.2019.07.077] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Accepted: 07/20/2019] [Indexed: 02/07/2023]
Abstract
Renal homeostasis is regulated by the interplay among different cell types in the kidneys including endothelial cells. In the present study we investigated the phenotypic regulation of endothelial cells by BRG1, a chromatin remodeling protein, in a mouse model of obstructive nephropathy (ON). We report that endothelial-specific deletion of BRG1 attenuated renal inflammation induced by unilateral ureteral tract obstruction (UUO) in mice, as evidenced by down-regulation of pro-inflammatory cytokines and diminished infiltration of immune cells. Moreover, endothelial BRG1 deficiency suppressed UUO-induced renal fibrosis in mice as measured by expression of pro-fibrogenic genes, picrosirius red staining of collagenous tissues, and quantification of hydroxylproline levels. Mechanistically, BRG1 activated the transcription of adhesion molecules and chemokines in endothelial cells by recruiting histone modifying enzymes leading to macrophage adhesion and chemotaxis. In conclusion, we propose that epigenetic regulation of endothelial function by BRG1 may play an active role in ON pathogenesis.
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Affiliation(s)
- Li Liu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Lei Mao
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China; Institute of Biomedical Research, Liaocheng University, Liaocheng, China
| | - Xiaoyan Wu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China; The Laboratory Center for Basic Medical Sciences, Nanjing Medical University, Nanjing, China.
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A non-autonomous role of MKL1 in the activation of hepatic stellate cells. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2019; 1862:609-618. [DOI: 10.1016/j.bbagrm.2019.03.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 01/07/2019] [Accepted: 03/30/2019] [Indexed: 01/20/2023]
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24
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Yang Y, Liu L, Li M, Cheng X, Fang M, Zeng Q, Xu Y. The chromatin remodeling protein BRG1 links ELOVL3 trans-activation to prostate cancer metastasis. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2019; 1862:834-845. [PMID: 31154107 DOI: 10.1016/j.bbagrm.2019.05.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 05/20/2019] [Accepted: 05/25/2019] [Indexed: 10/26/2022]
Abstract
Prostate cancer malignancies are intimately correlated with deregulated fatty acid metabolism. The underlying epigenetic mechanism is not fully understood. In the present study we investigated the mechanism whereby the chromatin remodeling protein BRG1 regulates the transcription of long-chain fatty acid elongase 3 (Elovl3) in prostate cancer cells. We report that in response to pro-metastatic cues (androgen and TGF-β) BRG1 expression was up-regulated along with Elvol3 in prostate cancer cells. BRG1 over-expression potentiated whereas BRG1 knockdown attenuated prostate cancer cell migration and invasion. Coincidently, Elovl3 was up-regulated following BRG1 over-expression and down-regulated after BRG1 knockdown in prostate cancer cells. Further analysis revealed that BRG1 interacted with and was recruited by retinoic acid receptor-related orphan receptor (RORγ) to the Elovl3 promoter to activate transcription. Chromatin immunoprecipitation (ChIP) profiling demonstrated that BRG1 interacted with histone acetyltransferase p300 to activate Elovl3 transcription. Depletion of p300 by siRNA or inhibition of p300 by curcumin attenuated Elovl3 trans-activation in prostate cancer cells. Together, our data identify a novel epigenetic pathway that links Elovl3 transcription to prostate cancer cell migration and invasion.
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Affiliation(s)
- Yuyu Yang
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China; Institute of Biomedical Research, Liaocheng University, Liaocheng, China
| | - Li Liu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Min Li
- Center for Male Reproductive Medicine, Department of Clinical Medicine, Jiangsu Health Vocational College, Nanjing, China
| | - Xian Cheng
- Jiangsu Institute of Nuclear Medicine, Wuxi, China
| | - Mingming Fang
- Center for Male Reproductive Medicine, Department of Clinical Medicine, Jiangsu Health Vocational College, Nanjing, China
| | - Qingqi Zeng
- Center for Male Reproductive Medicine, Department of Clinical Medicine, Jiangsu Health Vocational College, Nanjing, China.
| | - Yong Xu
- Institute of Biomedical Research, Liaocheng University, Liaocheng, China; Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China.
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25
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Kong M, Wu J, Fan Z, Chen B, Wu T, Xu Y. The histone demethylase Kdm4 suppresses activation of hepatic stellate cell by inducing MiR-29 transcription. Biochem Biophys Res Commun 2019; 514:16-23. [PMID: 31014673 DOI: 10.1016/j.bbrc.2019.04.105] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 04/14/2019] [Indexed: 12/21/2022]
Abstract
One of the hallmark events during liver fibrosis is the transition of quiescent hepatic stellate cells (HSC) into activated myofibroblasts, which are responsible for the production and deposition of pro-fibrogenic proteins. The epigenetic mechanism underlying HSC trans-differentiation is not fully understood. In the present study we investigated the contribution of histone H3K9 demethylase KDM4 in this process. We report that expression levels of KDM4 were down-regulated during HSC activation paralleling the up-regulation of alpha smooth muscle cell actin (Acta2), a marker of mature myofibroblast. Furthermore, HSCs isolated from mice induced to develop liver fibrosis exhibit lowered KDM4 expression compared to the control mice. In accordance, KDM4 depletion with siRNA accelerated HSC activation. Of interest, the loss of KDM4 was mirrored by the repression of miR-29, an antagonist of liver fibrosis, during HSC activation both in vitro and in vivo. KDM4 knockdown resulted in the down-regulation of miR-29 expression. Mechanistically, the sequence-specific transcription factor SREBP2 interacted with KDM4 to activate miR-29 transcription. In conclusion, our data delineate a novel epigenetic mechanism underlying HSC activation. Targeting this axis may yield potential therapeutics against liver fibrosis.
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Affiliation(s)
- Ming Kong
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Innovative Collaboration Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Jiahao Wu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Innovative Collaboration Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Zhiwen Fan
- Department of Pathology, Nanjing Drum Tower Hospital Affiliated with Nanjing University Medical School, Nanjing, China
| | - Bin Chen
- Department of Nursing, Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, China
| | - Teng Wu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Innovative Collaboration Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China.
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Innovative Collaboration Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China; Institute of Biomedical Research, Liaocheng University, Liaocheng, China.
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26
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Qiu L, Xu C, Chen J, Li Q, Jiang H. Downregulation of the transcriptional co-activator PCAF inhibits the proliferation and migration of vascular smooth muscle cells and attenuates NF-κB-mediated inflammatory responses. Biochem Biophys Res Commun 2019; 513:41-48. [PMID: 30935684 DOI: 10.1016/j.bbrc.2019.03.157] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 03/23/2019] [Indexed: 01/06/2023]
Abstract
P300/CBP-associated factor (PCAF) regulates vascular inflammation. This study was to explore the effect of PCAF on the proliferation and migrationof vascular smooth muscle cells (VSMCs) and neointimal hyperplasia in balloon-injured rat carotid artery. Downregulation of PCAF remarkably suppressed VSMCs proliferation and migration induced by lipopolysaccharide, and also significantly inhibit the nuclear translocation of nuclear factor-kappaB p65. Meanwhile, downregulation of PCAF inhibited the mRNA expression of tumor necrosis factor-α and interleukin-6, and also the levels in culture supernatants. Moreover, downregulation of PCAF profoundly reduced the intima area and the ratio of intima area to media area in balloon-injured rat carotid artery. In addition, the expression of PCNA and NF-κB p65 in intima were decreased by downregulation of PCAF. These results highlight that PCAF may be a potential target for prevention and treatment of neointimal hyperplasia and restenosis after angioplasty.
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Affiliation(s)
- Liqiang Qiu
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan, 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan, 430060, PR China
| | - Changwu Xu
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan, 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan, 430060, PR China.
| | - Jing Chen
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan, 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan, 430060, PR China
| | - Qi Li
- Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, PR China
| | - Hong Jiang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan, 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan, 430060, PR China
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Zhang Y, Yuan Y, Li Z, Chen H, Fang M, Xiao P, Xu Y. An interaction between BRG1 and histone modifying enzymes mediates lipopolysaccharide-induced proinflammatory cytokines in vascular endothelial cells. J Cell Biochem 2019; 120:13216-13225. [PMID: 30891798 DOI: 10.1002/jcb.28595] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Revised: 02/11/2019] [Accepted: 02/14/2019] [Indexed: 12/26/2022]
Abstract
Vascular inflammation is the culprit for a host of human diseases. The underlying mechanism, however, is not definitively elucidated. In the present study, we investigated the interplay between different epigenetic factors during lipopolysaccharide (LPS) induced synthesis of proinflammatory cytokines in cultured vascular endothelial cells. We report that in response to LPS treatment, NF-κB was deplored to its target promoters along with the chromatin remodeling protein BRG1. Paralleling these changes trimethylated H3K9 became erased from while trimethylated H3K4 started to accumulate on the NF-κB target promoters. Further analysis revealed that LPS stimulation resulted in sequential recruitment of the H3K9 tri-demethylase JMJD2A and the H3K4 trimethyltransferase SET1A to the NF-κB target promoters. JMJD2A mediated-H3K9 demethylation served as a prerequisite for SET1A to bind to the NF-κB target promoters. Both JMJD2A and SET1A were essential for LPS-induced transactivation of proinflammatory cytokines by sustaining the binding of NF-κB. Of key importance, BRG1 coordinated the sequential recruit of and the interplay between JMJD2A and SET1A. In conclusion, our data unveil a novel epigenetic mechanism that contributes to LPS-induced vascular inflammation.
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Affiliation(s)
- Yuanyuan Zhang
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China.,Department of Cardiology, Affiliated Hospital to Hainan Medical University, Haikou, China
| | - Yibiao Yuan
- School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
| | - Zilong Li
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China
| | - Huan Chen
- Department of Bioinformatics, School of Biomedical Engineering and Informatics, Nanjing Medical University, Nanjing, China
| | - Mingming Fang
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China.,Department of Clinical Medicine, Jiangsu Health Vocational College, Nanjing, China
| | - Pingxi Xiao
- Department of Cardiology, Sir Run Run Hospital Affiliated to Nanjing MedicalUniversity, Nanjing, China
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease and Collaborative Innovation Center for Cardiovascular Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China.,Institute of Biomedical Research, Liaocheng University, Liaocheng, China
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28
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Megakaryocytic leukemia 1 (MKL1) mediates high glucose induced epithelial-mesenchymal transition by activating LOX transcription. Biochem Biophys Res Commun 2018; 509:633-640. [PMID: 30553442 DOI: 10.1016/j.bbrc.2018.12.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 12/04/2018] [Indexed: 12/17/2022]
Abstract
Diabetic retinopathy (DR) is one of the most devastating complications of diabetes mellitus. When exposed to high glucose (HG), retinal epithelial cells undergo profound alterations both morphologically and functionally in a well-conserved process known as epithelial-to-mesenchymal transition (EMT). The mechanism governing HG-induced EMT in retinal epithelial cells is not completely understood. Here we report that treatment with 25 mM glucose led to EMT in retinal pigmented epithelial cells (RPE) characterized by a simultaneous down-regulation of E-Cadherin (encoded by CDH1) and up-regulation of alpha smooth muscle actin (encoded by ACTA2). HG-induced EMT in RPEs was accompanied by augmented expression and enhanced nuclear enrichment of MKL1, a transcriptional modulator. In contrast, MKL1 knockdown by siRNA or inhibition by CCG-1423 abrogated HG-induced EMT in RPEs. Of interest, MKL1 mediated the transcriptional activation of LOX, a mesenchymal marker, in RPEs in response to HG stimulation. Mechanistically, MKL1 interacted with and was recruited by AP-1 to the proximal LOX promoter to promote LOX trans-activation likely through altering the chromatin structure. Finally, LOX depletion by siRNA or inhibition by aminopropionitrile in RPEs abolished HG-induced EMT. In conclusion, our data support a role for MKL1 in mediating HG-induced EMT in retinal epithelial cells via epigenetic activation of LOX transcription.
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Zhang J, Xie M, Xia L, Yu T, He F, Zhao C, Qiu W, Zhao D, Liu Y, Gong Y, Yao C, Liu L, Wang Y. Sublytic C5b-9 Induces IL-23 and IL-36a Production by Glomerular Mesangial Cells via PCAF-Mediated KLF4 Acetylation in Rat Thy-1 Nephritis. THE JOURNAL OF IMMUNOLOGY 2018; 201:3184-3198. [PMID: 30404815 DOI: 10.4049/jimmunol.1800719] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 10/01/2018] [Indexed: 11/19/2022]
Abstract
Sublytic C5b-9 formation on glomerular mesangial cells in rat Thy-1 nephritis (Thy-1N), a model of human mesangioproliferative glomerulonephritis, is accompanied by the production of proinflammatory cytokines, but the relationship between sublytic C5b-9 and cytokine synthesis and the underlying mechanism remains unclear. To explore the problems mentioned above, in this study, we first examined the levels of proinflammatory ILs (e.g., IL-23 and IL-36a) as well as transcription factor (KLF4) and coactivator (PCAF) in the renal tissues of Thy-1N rats and in the glomerular mesangial cell line (HBZY-1) stimulated by sublytic C5b-9. Then, we further determined the role of KLF4 and PCAF in sublytic C5b-9-induced IL-23 and IL-36a production as well as the related mechanism. Our results showed that the levels of KLF4, PCAF, IL-23, and IL-36a were obviously elevated. Mechanistic investigation revealed that sublytic C5b-9 stimulation could increase IL-23 and IL-36a synthesis through KLF4 and PCAF upregulation, and KLF4 and PCAF could form a complex, binding to the IL-23 or IL-36a promoter in a KLF4-dependent manner, causing gene transcription. Importantly, KLF4 acetylation by PCAF contributed to sublytic C5b-9-induced IL-23 and IL-36a transcription. Besides, the KLF4 binding regions on IL-23 or IL-36a promoters and the KLF4 lysine site acetylated by PCAF were identified. Furthermore, silencing renal KLF4 or PCAF gene could significantly inhibit IL-23 or IL-36a secretion and tissue damage of Thy-1N rats. Collectively, these findings implicate that the KLF4/PCAF interaction and KLF4 acetylation by PCAF play a pivotal role in the sublytic C5b-9-mediated IL-23 and IL-36a production of Thy-1N rats.
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Affiliation(s)
- Jing Zhang
- Department of Immunology, Nanjing Medical University, Nanjing, Jiangsu 211166, People's Republic of China
| | - Mengxiao Xie
- Department of Immunology, Nanjing Medical University, Nanjing, Jiangsu 211166, People's Republic of China
| | - Lu Xia
- Department of Immunology, Nanjing Medical University, Nanjing, Jiangsu 211166, People's Republic of China
| | - Tianyi Yu
- Department of Immunology, Nanjing Medical University, Nanjing, Jiangsu 211166, People's Republic of China
| | - Fengxia He
- Department of Pathology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210011, People's Republic of China; and
| | - Chenhui Zhao
- Department of Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, People's Republic of China
| | - Wen Qiu
- Department of Immunology, Nanjing Medical University, Nanjing, Jiangsu 211166, People's Republic of China
| | - Dan Zhao
- Department of Immunology, Nanjing Medical University, Nanjing, Jiangsu 211166, People's Republic of China
| | - Yu Liu
- Department of Immunology, Nanjing Medical University, Nanjing, Jiangsu 211166, People's Republic of China
| | - Yajuan Gong
- Department of Immunology, Nanjing Medical University, Nanjing, Jiangsu 211166, People's Republic of China
| | - Chunyan Yao
- Department of Immunology, Nanjing Medical University, Nanjing, Jiangsu 211166, People's Republic of China
| | - Longfei Liu
- Department of Immunology, Nanjing Medical University, Nanjing, Jiangsu 211166, People's Republic of China
| | - Yingwei Wang
- Department of Immunology, Nanjing Medical University, Nanjing, Jiangsu 211166, People's Republic of China;
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30
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Hypermethylated in cancer 1 (HIC1) mediates high glucose induced ROS accumulation in renal tubular epithelial cells by epigenetically repressing SIRT1 transcription. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2018; 1861:917-927. [DOI: 10.1016/j.bbagrm.2018.08.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 08/09/2018] [Accepted: 08/22/2018] [Indexed: 01/22/2023]
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Suryanarayanan V, Rajavel T, Devi KP, Singh SK. Structure based identification and biological evaluation of novel and potent inhibitors of PCAF catalytic domain. Int J Biol Macromol 2018; 120:823-834. [PMID: 30118769 DOI: 10.1016/j.ijbiomac.2018.08.052] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 08/08/2018] [Accepted: 08/09/2018] [Indexed: 12/14/2022]
Abstract
p300/CBP Associated Factor (PCAF), a GNAT family member protein, represent a valid target for therapeutic interventions since its dysfunction has implicated in variety of diseases like cancer, diabetes, inflammatory diseases, etc. Despite its potential for therapeutics, only a small number of PCAF inhibitors were reported. Hence, in this study, the catalytic domain of PCAF was explored to screen novel, potent and cell permeable inhibitor from three small molecule databases like Life Chemical, Maybridge and Chembridge by using Structure Based Virtual Screening (SBVS) method. Further, Induced Fit Docking, Binding Free Energy calculation, Single Point Energy calculation and Molecular Dynamics Simulation were performed on selected hits. In silico results revealed that F2209-0381 has higher binding energy of -109.722 and have greater cell permeability (QPPCaco = 1456.764; QPPMDCK = 742.941) than rest of hits. Cytotoxicity effect and protein expression analysis of F2209-0381 on A549 cells reveals that it exhibited strong inhibition with IC50 value of 58.31 μg/ml and significantly reduced the expression of PCAF after 72 h time point. Thus, this study warrants that F2209-0381 could become a novel, potent and cell permeable drug of PCAF thereby it could combat its mediated diseases.
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Affiliation(s)
- Venkatesan Suryanarayanan
- Computer Aided Drug Design and Molecular Modelling Lab, Department of Bioinformatics, Alagappa University, Karaikudi 630 004, Tamil Nadu, India
| | - Tamilselvam Rajavel
- Department of Biotechnology, Alagappa University, Karaikudi, 630 004, Tamil Nadu, India
| | - Kasi Pandima Devi
- Department of Biotechnology, Alagappa University, Karaikudi, 630 004, Tamil Nadu, India
| | - Sanjeev Kumar Singh
- Computer Aided Drug Design and Molecular Modelling Lab, Department of Bioinformatics, Alagappa University, Karaikudi 630 004, Tamil Nadu, India.
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Li Z, Chen B, Dong W, Xu W, Song M, Fang M, Guo J, Xu Y. Epigenetic activation of PERP transcription by MKL1 contributes to ROS-induced apoptosis in skeletal muscle cells. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2018; 1861:S1874-9399(18)30177-9. [PMID: 30056131 DOI: 10.1016/j.bbagrm.2018.07.011] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 07/19/2018] [Accepted: 07/24/2018] [Indexed: 12/25/2022]
Abstract
Excessive reactive oxygen species (ROS) causes irreparable damages to cells and commit cells to programmed cell death or apoptosis. A panel of well-documented pro-apoptotic genes, including p53 apoptosis effector related to PMP-22 (PERP), are up-regulated and collectively mediate ROS induced apoptosis. The epigenetic mechanism whereby ROS stimulates PERP transcription, however, lacks in-depth characterization. Here we report that the transcriptional modulator megakaryocytic leukemia 1 (MKL1) is activated by H2O2 treatment in skeletal muscle cells (C2C12). Small interfering RNA (siRNA) mediated silencing or small-molecule compound (CCG-1423) mediated inhibition of MKL1 attenuated H2O2 induced apoptosis of C2C12 cells. Over-expression of MKL1 potentiated trans-activation of PERP whereas MKL1 ablation/inhibition abrogated the induction of PERP by H2O2 in C2C12 cells. Mechanistically, MKL1 interacted with and was recruited to the PERP promoter by the transcription factor E2F1. Once bound to the PERP promoter, MKL1 engaged the histone demethylase KDM3A to modulate the chromatin structure surrounding the PERP promoter thereby leading to PERP trans-activation. Depletion of either E2F1 or KDM3A blocked the induction of PERP by H2O2. In conclusion, our data illustrate a novel epigenetic pathway that links PERP transcription to ROS-induced apoptosis in skeletal muscle cells.
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Affiliation(s)
- Zilong Li
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China; Institute of Biomedical Research, Liaocheng University, Liaocheng, China
| | - Baoyu Chen
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Wenhui Dong
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Wenping Xu
- Department of Medicine, Jiangsu Health Vocational College, Nanjing, China
| | - Mingzi Song
- Department of Medicine, Jiangsu Health Vocational College, Nanjing, China
| | - Mingming Fang
- Department of Medicine, Jiangsu Health Vocational College, Nanjing, China
| | - Junli Guo
- Cardiovascular Disease and Research Institute, Affiliated Hospital of Hainan Medical College, Haikou, Hainan, China.
| | - Yong Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Pathophysiology, Nanjing Medical University, Nanjing, China; Institute of Biomedical Research, Liaocheng University, Liaocheng, China.
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Zhang X, Chen J, Sun L, Xu Y. SIRT1 deacetylates KLF4 to activate Claudin-5 transcription in ovarian cancer cells. J Cell Biochem 2017; 119:2418-2426. [PMID: 28888043 DOI: 10.1002/jcb.26404] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 08/30/2017] [Indexed: 12/23/2022]
Abstract
Malignant cancers are distinguished from more benign forms of cancers by enhanced ability to disseminate. A number of factors aid the migration and invasion of malignant cancer cells. Epithelial-to-mesenchymal transition (EMT), which greatly facilitates the dissemination of cancer cells, is characterized by the loss of epithelial markers and the acquisition of mesenchymal markers thereby rendering the cells more migratory and invasive. We have previously shown that the class III lysine deacetylase SIRT1 plays a critical role curbing the metastasis of ovarian cancer cells partly by blocking EMT. Here we investigated the mechanism by which SIRT1 regulates the transcription of Claudin 5 (CLDN5), an epithelial marker gene, in ovarian cancer cells. SIRT1 activation or over-expression up-regulated CLDN5 expression while SIRT1 inhibition or depletion down-regulated CLDN5 expression. SIRT1 interacted with and deacetylated Kruppel-like factor 4 (KLF4), a known transcriptional activator for CLDN5. Deacetylation by SIRT1 promoted nuclear accumulation of KLF4 and enhanced the binding of KLF4 to the CLDN5 promoter in the nucleus. SIRT1-mediated up-regulation of CLDN5 was abrogated in the absence of KLF4. In accordance, KLF4 depletion by siRNA rendered ovarian cancer cells more migratory and invasive despite of SIRT1 activation or over-expression. In conclusion, our data suggest that SIRT1 activates CLDN5 transcription by deacetylating and potentiating KLF4.
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Affiliation(s)
- Xinjian Zhang
- Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Junliang Chen
- Department of Pathophysiology, Wuxi College of Medicine, Jiangnan University, Nanjing, Jiangsu, China
| | - Lina Sun
- Department of Pathology and Pathophysiology, Soochow University, Suzhou, Jiangsu, China
| | - Yong Xu
- Department of Pathophysiology, Nanjing Medical University, Nanjing, China
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HADC5 deacetylates MKL1 to dampen TNF-α induced pro-inflammatory gene transcription in macrophages. Oncotarget 2017; 8:94235-94246. [PMID: 29212224 PMCID: PMC5706870 DOI: 10.18632/oncotarget.21670] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 09/18/2017] [Indexed: 12/20/2022] Open
Abstract
Macrophage-dependent inflammatory response on the one hand functions as a key line of defense in host immunity but on the other hand underlies the pathogenesis of a host of human pathologies when aberrantly activated. Our previous investigations have led to the identification of megakaryocytic leukemia 1 (MKL1) as a key co-factor of NF-κB/p65 participating in TNF-α induced pro-inflammatory transcription in macrophages. How post-translational modifications contribute to the modulation of MKL1 activity remains an underexplored subject matter. Here we report that the lysine deacetylase HDAC5 interacts with and deacetylates MKL1 in cells. TNF-α treatment down-regulates HDAC5 expression and expels HDAC5 from the promoters of pro-inflammatory genes in macrophages. In contrast, over-expression of HDAC5 attenuates TNF-α induced pro-inflammatory transcription. Mechanistically, HDAC5-mediated MKL1 deacetylation disrupts the interaction between MKL1 and p65. In addition, deacetylation of MKL1 by HDAC5 blocks its nuclear translocation in response to TNF-α treatment. In conclusion, our work has identified an important pathway that contributes to the regulation of pro-inflammatory response in macrophages.
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