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Kang X, Li C, Liu S, Baldwin RL, Liu GE, Li CJ. Genome-Wide Acetylation Modification of H3K27ac in Bovine Rumen Cell Following Butyrate Exposure. Biomolecules 2023; 13:1137. [PMID: 37509173 PMCID: PMC10377523 DOI: 10.3390/biom13071137] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 07/12/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023] Open
Abstract
Butyrate contributes epigenetically to the changes in cellular function and tissue development of the rumen in ruminant animals, which might be achieved by its genetic or epigenetic regulation of gene expression. To explore the role of butyrate on bovine rumen epithelial function and development, this study characterized genome-wide H3K27ac modification changes and super-enhancer profiles in rumen epithelial primary cells (REPC) induced with butyrate by ChIP-seq, and analyzed its effects on gene expression and functional pathways by integrating RNA-seq data. The results showed that genome-wide acetylation modification was observed in the REPC with 94,675 and 48,688 peaks in the butyrate treatment and control group, respectively. A total of 9750 and 5020 genes with increased modification (H3K27ac-gain) and decreased modification (H3K27ac-loss) were detected in the treatment group. The super-enhancer associated genes in the butyrate-induction group were involved in the AMPK signaling pathway, MAPK signaling pathway, and ECM-receptor interaction. Finally, the up-regulated genes (PLCG1, CLEC3B, IGSF23, OTOP3, ADTRP) with H3K27ac gain modification by butyrate were involved in cholesterol metabolism, lysosome, cell adhesion molecules, and the PI3K-Akt signaling pathway. Butyrate treatment has the role of genome-wide H3K27ac acetylation on bovine REPC, and affects the changes in gene expression. The effect of butyrate on gene expression correlates with the acetylation of the H3K27ac level. Identifying genome-wide acetylation modifications and expressed genes of butyrate in bovine REPC cells will expand the understanding of the biological role of butyrate and its acetylation.
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Affiliation(s)
- Xiaolong Kang
- Animal Genomics and Improvement Laboratory, Henry A. Wallace Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD 20705, USA
- Key Laboratory of Ruminant Molecular and Cellular Breeding, College of Animal Science and Technology, Ningxia University, Yinchuan 750021, China
| | - Chenglong Li
- Key Laboratory of Ruminant Molecular and Cellular Breeding, College of Animal Science and Technology, Ningxia University, Yinchuan 750021, China
| | - Shuli Liu
- Animal Genomics and Improvement Laboratory, Henry A. Wallace Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD 20705, USA
| | - Ransom L Baldwin
- Animal Genomics and Improvement Laboratory, Henry A. Wallace Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD 20705, USA
| | - George E Liu
- Animal Genomics and Improvement Laboratory, Henry A. Wallace Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD 20705, USA
| | - Cong-Jun Li
- Animal Genomics and Improvement Laboratory, Henry A. Wallace Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD 20705, USA
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Liu X, Wang Y, Li J, Wu B, Wang S, Guo Q, Liu Y. To study the protective effect of Huangqi Baihe Granules on Radiation brain injury based on network pharmacology and experiment. JOURNAL OF ETHNOPHARMACOLOGY 2023:116610. [PMID: 37150423 DOI: 10.1016/j.jep.2023.116610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 05/02/2023] [Accepted: 05/04/2023] [Indexed: 05/09/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Huangqi baihe Granules (HQBHG), which is a key Chinese medical prescription, has a remarkable efficacy in oxidative stress and inflammation. Nevertheless, the therapeutic effect on Radiation brain injury (RBI) has rarely been studied. AIM OF THE STUDY The study aimed to verify the effect of HQBHG against RBI and explore its potential mechanism. METHODS The potential targets and mechanisms of HQBHG against RBI were predicted by network pharmacology and verified by established rat model of RBI Firstly, the therapeutic effect of HQBHG in RBI was confirmed by water maze test, HE staining and Enzyme-linked immunosorbent assay (ELISA). Secondly, the potential critical anti-RBI pathway of HQBHG was further explored by water maze, HE staining, immunofluorescence assays, ELISA and western blot. RESULTS A total of 43 HQBHG anti-RBI targets were obtained. Gene Ontology (Go) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional annotations showed that the treatment of HQBHG in RBI might be mainly related to oxidative stress, inflammation and PI3K/AKT pathway. Experimental studies have indicated that HQBHG can improve spatial learning and memory ability, alleviate pathological damage of brain tissue in RBI of rats. HQBHG also can down-regulate the levels of IL-1β, TNF-α, ROS and MDA, meanwhile, GSH was significantly up-regulated. In addition, the HQBHG can increase the protein expression phosphorylations PI3K (p-PI3K), phosphorylations AKT(p-AKT) and Nrf2 in the brain tissue of RBI. CONCLUSION HQBHG may alleviated RBI by regulated oxidative stress and inflammatory response through PI3K/AKT/Nrf2 pathway.
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Affiliation(s)
- Xiuzhu Liu
- Gansu University Key Laboratory for Molecular Medicine & Chinese Medicine Prevention and Treatment of Major Diseases, Gansu University of Chinese Medicine, Lanzhou, 730000, Gansu Province, China.
| | - Yanru Wang
- Gansu University Key Laboratory for Molecular Medicine & Chinese Medicine Prevention and Treatment of Major Diseases, Gansu University of Chinese Medicine, Lanzhou, 730000, Gansu Province, China.
| | - Jiawei Li
- Gansu University Key Laboratory for Molecular Medicine & Chinese Medicine Prevention and Treatment of Major Diseases, Gansu University of Chinese Medicine, Lanzhou, 730000, Gansu Province, China.
| | - Bingbing Wu
- 940th Hospital of Chinese People 's Liberation Army Joint Support Force, Lanzhou, 730050, Gansu Province, China.
| | - Siyu Wang
- Gansu University Key Laboratory for Molecular Medicine & Chinese Medicine Prevention and Treatment of Major Diseases, Gansu University of Chinese Medicine, Lanzhou, 730000, Gansu Province, China.
| | - Qingyang Guo
- 940th Hospital of Chinese People 's Liberation Army Joint Support Force, Lanzhou, 730050, Gansu Province, China.
| | - Yongqi Liu
- Gansu University Key Laboratory for Molecular Medicine & Chinese Medicine Prevention and Treatment of Major Diseases, Gansu University of Chinese Medicine, Lanzhou, 730000, Gansu Province, China.
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Chan GHH, Chan E, Kwok CTK, Leung GPH, Lee SMY, Seto SW. The role of p53 in the alternation of vascular functions. Front Pharmacol 2022; 13:981152. [PMID: 36147350 PMCID: PMC9485942 DOI: 10.3389/fphar.2022.981152] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 08/17/2022] [Indexed: 11/13/2022] Open
Abstract
Ageing is a risk factor for many degenerative diseases. Cardiovascular diseases (CVDs) are usually big burdens for elderly, caregivers and the health system. During the aging process, normal functions of vascular cells and tissue progressively lost and eventually develop vascular diseases. Endothelial dysfunction, reduced bioavailability of endothelium-derived nitric oxide are usual phenomena observed in patients with cardiovascular diseases. Myriad of studies have been done to investigate to delay the vascular dysfunction or improve the vascular function to prolong the aging process. Tumor suppressor gene p53, also a transcription factor, act as a gatekeeper to regulate a number of genes to maintain normal cell function including but not limited to cell proliferation, cell apoptosis. p53 also crosstalk with other key transcription factors like hypoxia-inducible factor 1 alpha that contribute to the progression of cardiovascular diseases. Therefore, in recent three decades, p53 has drawn scientists’ attention on its effects in vascular function. Though the role of tumor suppressor gene p53 is still not clear in vascular function, it is found to play regulatory roles and may involve in vascular remodeling, atherosclerosis or pulmonary hypertension. p53 may have a divergent role in endothelial and vascular muscle cells in those conditions. In this review, we describe the different effects of p53 in cardiovascular physiology. Further studies on the effects of endothelial cell-specific p53 deficiency on atherosclerotic plaque formation in common animal models are required before the therapeutic potential can be realized.
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Affiliation(s)
- Gabriel Hoi-Huen Chan
- Division of Science, Engineering and Health Studies, College of Professional and Continuing Education, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Enoch Chan
- School of Clinical Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Carsten Tsun-Ka Kwok
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - George Pak-Heng Leung
- Department of Pharmacology and Pharmacy, The University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - Simon Ming-Yuen Lee
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Avenida da Universidade, Taipa, China
| | - Sai-Wang Seto
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
- Research Centre for Chinese Medicine Innovation, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
- NICM Health Research Institute, Western Sydney University, Penrith, NSW, Australia
- *Correspondence: Sai-Wang Seto,
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Docherty CK, Strembitska A, Baker CP, Schmidt FF, Reay K, Mercer JR. Inducing Energetic Switching Using Klotho Improves Vascular Smooth Muscle Cell Phenotype. Int J Mol Sci 2021; 23:ijms23010217. [PMID: 35008643 PMCID: PMC8745077 DOI: 10.3390/ijms23010217] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/18/2021] [Accepted: 12/22/2021] [Indexed: 01/18/2023] Open
Abstract
The cardiovascular disease of atherosclerosis is characterised by aged vascular smooth muscle cells and compromised cell survival. Analysis of human and murine plaques highlights markers of DNA damage such as p53, Ataxia telangiectasia mutated (ATM), and defects in mitochondrial oxidative metabolism as significant observations. The antiageing protein Klotho could prolong VSMC survival in the atherosclerotic plaque and delay the consequences of plaque rupture by improving VSMC phenotype to delay heart attacks and stroke. Comparing wild-type VSMCs from an ApoE model of atherosclerosis with a flox'd Pink1 knockout of inducible mitochondrial dysfunction we show WT Pink1 is essential for normal cell viability, while Klotho mediates energetic switching which may preserve cell survival. METHODS Wild-type ApoE VSMCs were screened to identify potential drug candidates that could improve longevity without inducing cytotoxicity. The central regulator of cell metabolism AMP Kinase was used as a readout of energy homeostasis. Functional energetic switching between oxidative and glycolytic metabolism was assessed using XF24 technology. Live cell imaging was then used as a functional readout for the WT drug response, compared with Pink1 (phosphatase-and-tensin-homolog (PTEN)-induced kinase-1) knockout cells. RESULTS Candidate drugs were assessed to induce pACC, pAMPK, and pLKB1 before selecting Klotho for its improved ability to perform energetic switching. Klotho mediated an inverse dose-dependent effect and was able to switch between oxidative and glycolytic metabolism. Klotho mediated improved glycolytic energetics in wild-type cells which were not present in Pink1 knockout cells that model mitochondrial dysfunction. Klotho improved WT cell survival and migration, increasing proliferation and decreasing necrosis independent of effects on apoptosis. CONCLUSIONS Klotho plays an important role in VSMC energetics which requires Pink1 to mediate energetic switching between oxidative and glycolytic metabolism. Klotho improved VSMC phenotype and, if targeted to the plaque early in the disease, could be a useful strategy to delay the effects of plaque ageing and improve VSMC survival.
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New Insights for BPIFB4 in Cardiovascular Therapy. Int J Mol Sci 2020; 21:ijms21197163. [PMID: 32998388 PMCID: PMC7583974 DOI: 10.3390/ijms21197163] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 09/23/2020] [Accepted: 09/25/2020] [Indexed: 02/06/2023] Open
Abstract
Aging is the most relevant risk factor for cardiovascular diseases which are the main cause of mortality in industrialized countries. In this context, there is a progressive loss of cardiovascular homeostasis that translates in illness and death. The study of long living individuals (LLIs), which show compression of morbidity toward the end of their life, is a valuable approach to find the key to delay aging and postpone associate cardiovascular events. A contribution to the age-related decline of cardiovascular system (CVS) comes from the immune system; indeed, it is dysfunctional during aging, a process described as immunosenescence and comprises the combination of several processes overpowering both innate and adaptative immune system. We have recently discovered a longevity-associated variant (LAV) in bactericidal/permeability-increasing fold-containing family B member 4 (BPIFB4), which is a secreted protein able to enhance endothelial function through endothelial nitric oxide synthase (eNOS) activation and capable to protect from hypertension, atherosclerosis, diabetic cardiopathy, frailty, and inflammaging. Here, we sum up the state of the art of the mechanisms involved in the main pathological processes related to CVD (atherosclerosis, aging, diabetic cardiopathy, and frailty) and shed light on the therapeutic effects of LAV-BPIFB4 in these contexts.
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Zhao TC, Wang Z, Zhao TY. The important role of histone deacetylases in modulating vascular physiology and arteriosclerosis. Atherosclerosis 2020; 303:36-42. [PMID: 32535412 DOI: 10.1016/j.atherosclerosis.2020.04.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 04/18/2020] [Accepted: 04/29/2020] [Indexed: 12/18/2022]
Abstract
Cardiovascular diseases are the leading cause of deaths in the world. Endothelial dysfunction followed by inflammation of the vessel wall leads to atherosclerotic lesion formation that causes ischemic heart and myocardial hypertrophy, which ultimately progress into cardiac dysfunction and failure. Histone deacetylases (HDACs) have been recognized to play crucial roles in cardiovascular disease, particularly in the epigenetic regulation of gene transcription in response to a variety of stresses. The unique nature of HDAC regulation includes that HDACs form a complex co-regulatory network with other transcription factors, deacetylate histones and non-histone proteins to facilitate the regulatory mechanism of the vascular system. The selective HDAC inhibitors are considered as the most promising target in cardiovascular disease, especially for preventing cardiac hypertrophy. In this review, we discuss our present knowledge of the cellular and molecular basis of HDACs in mediating the biological function of vascular cells and related pharmacologic interventions in vascular disease.
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Affiliation(s)
- Ting C Zhao
- Department of Surgery and Plastics Surgery, Brown University, Rhode Island Hospital, Providence, RI, USA.
| | - Zhengke Wang
- Department of Surgery, Boston University Medical School, Roger Williams Medical Center, Providence, 50 Maude Street, RI, 02908, USA
| | - Tina Y Zhao
- University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
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Sun L, Wang C, Yuan Y, Guo Z, He Y, Ma W, Zhang J. Downregulation of HDAC1 suppresses media degeneration by inhibiting the migration and phenotypic switch of aortic vascular smooth muscle cells in aortic dissection. J Cell Physiol 2020; 235:8747-8756. [PMID: 32324261 DOI: 10.1002/jcp.29718] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 02/28/2020] [Accepted: 03/30/2020] [Indexed: 01/27/2023]
Abstract
Although much progress has been made in the diagnosis and treatment of thoracic aortic dissection (TAD), the overall morbidity and mortality rates of TAD are still high. Therefore, the molecular pathogenesis and etiology of TAD need to be elucidated. In this study, we found that histone deacetylase 1 (HDAC1) expression is dramatically higher in the aortic wall of patients with TAD (than that in a normal group) and negatively correlates with the levels of the vascular smooth muscle cell (SMC) contractile-phenotype markers. Knockdown of HDAC1 upregulated both smooth muscle 22 α (SM22α) and α-smooth muscle actin (α-SMA) in platelet-derived growth factor (PDGF)-BB-treated and -untreated SMCs. In addition, the knockdown of HDAC1 markedly decreased SMC viability and migration in contrast to the control group under the conditions of quiescence and PDGF-BB treatment. We also showed that the expression of polycystic kidney disease 1 (PKD1) is decreased in the aortic wall of patients with TAD and negatively correlates with HDAC1 expression. Overexpressed PKD1 obviously increased SM22α and α-SMA expression and reduced the viability and migration of SMCs, but these effects were attenuated by HDAC1. Furthermore, we demonstrated that HDAC1 serves as an important modulator of the migration and phenotypic switch of SMCs by suppressing the PKD1- mammalian target of the rapamycin signaling pathway. HDAC1 downregulation inhibited media degeneration and attenuated the loss of elastic-fiber integrity in a mouse model of TAD. Our results suggest that HDAC1 might be a new target for the treatment of a macrovascular disease such as TAD.
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Affiliation(s)
- Lin Sun
- Department of Cardiovascular Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Chunping Wang
- Department of Thoracic-cardiovascular Surgery, Tongji Hospital, Tongji University School of Medicine, Shanghai, China
| | - Ye Yuan
- Department of Vascular Surgery, The Affiliated Wuxi People's Hospital of Nanjing Medical University, Wuxi, China
| | - Zhen Guo
- Department of Cardiovascular Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Yubin He
- Department of Cardiovascular Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.,Department of Cardiovascular Surgery, Huashan Hospital North Affiliated to Fudan University, Shanghai, China
| | - Wenrui Ma
- Department of Cardiothoracic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Jing Zhang
- Department of Cardiovascular Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
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Sessa F, Messina G, Russo R, Salerno M, Castruccio Castracani C, Distefano A, Li Volti G, Calogero AE, Cannarella R, Mongioi' LM, Condorelli RA, La Vignera S. Consequences on aging process and human wellness of generation of nitrogen and oxygen species during strenuous exercise. Aging Male 2020; 23:14-22. [PMID: 29950140 DOI: 10.1080/13685538.2018.1482866] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Impairment of antioxidant defense system and increase in metabolic rate and production of reactive oxygen species have been demonstrated in strenuous exercise. Both at rest and during contractile activity, skeletal muscle generates a very complex set of reactive nitrogen and oxygen species; the main generated are superoxide and nitric oxide. The nature of the contractile activity influences the pattern and the magnitude of this reactive oxygen and nitrogen species (ROS) generation. The intracellular pro-oxidant/antioxidant homeostasis undergoes alteration owing to strenuous exercise and the major identified sources of intracellular free radical generation during physical activity are the mitochondrial electron transport chain, polymorphoneutrophil, and xanthine oxidase. Reactive oxygen species increased tissue susceptibility to oxidative damage and pose a serious threat to the cellular antioxidant defense system. The possible dangerous consequences of the aging process and human wellness are emphasized in this review.
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Affiliation(s)
- Francesco Sessa
- Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy
| | - Giovanni Messina
- Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy
| | - Raffaele Russo
- Department of Orthopaedic and Traumatology, Pellegrini Hospital, Naples, Italy
| | - Monica Salerno
- Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy
| | | | - Alfio Distefano
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Giovanni Li Volti
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Aldo E Calogero
- Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Rossella Cannarella
- Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Laura M Mongioi'
- Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Rosita A Condorelli
- Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Sandro La Vignera
- Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
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Song W, Puttabyatappa M, Zeng L, Vazquez D, Pennathur S, Padmanabhan V. Developmental programming: Prenatal bisphenol A treatment disrupts mediators of placental function in sheep. CHEMOSPHERE 2020; 243:125301. [PMID: 31726260 PMCID: PMC7243413 DOI: 10.1016/j.chemosphere.2019.125301] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 10/21/2019] [Accepted: 11/02/2019] [Indexed: 05/09/2023]
Abstract
Gestational Bisphenol A (BPA) exposure is associated with low birth weight. We hypothesized that the low birth weight is the consequence of reduced placental efficiency and a function of BPA-induced inflammatory, oxidative, lipotoxic, angiogenic, steroidal and fibrotic changes involving epigenetic alterations. Placentomes were collected during early (day 65) and mid (day 90) gestation (term ∼147 days) from control and BPA (gestational day 30-90)-treated pregnant sheep. BPA treatment: reduced placental efficiency and fetal weight; increased interleukin 8, lipid peroxidation marker, antioxidants, aromatase, 17 alpha-hydroxylase, estrogen receptor 2, insulin like growth factor (IGF) 2 receptor and IGF binding proteins (IGFBP), and histone deacetylase 1 and 2; reduced tumor necrosis factor alpha and IGF1 receptor at early gestation (Day 65). Gestational BPA-induced mid-gestational changes include: reduced angiogenic factor hypoxia inducible factor 1 alpha; increased IL1beta, oxidative stress markers, triglyceride, 17alpha hydroxylase, IGFBP 1, DNA methyltransferase 3 A and histone deacetylase 1. These findings indicate that gestational BPA, either acting directly or by altering steroidal input, produces early/mid-gestational-specific epigenetic changes culminating in placental disruptions at several levels, in keeping with time-specific/time-lagged pregnancy-associated changes in placental efficiency and fetal weight. The reduced early-gestational placental efficiency may be a function of increased inflammation/oxidative stress and reduced IGF bioavailability with the mid-gestational restoration of placental efficiency likely driven by improved IGF bioavailability and the time-lagged response to antioxidant increase. This compensation, the result of time-lagged response to increases in negative mediators of placental function must have failed with pregnancy advancement to explain the low birthweight outcome.
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Affiliation(s)
- Wenhui Song
- The Fourth Hospital of Shijiazhuang, Shijiazhuang, Hebei, 050011, PR China; Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | | | - Lixia Zeng
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Delia Vazquez
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
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Pan CH, Chen CJ, Shih CM, Wang MF, Wang JY, Wu CH. Oxidative stress-induced cellular senescence desensitizes cell growth and migration of vascular smooth muscle cells through down-regulation of platelet-derived growth factor receptor-beta. Aging (Albany NY) 2019; 11:8085-8102. [PMID: 31584878 PMCID: PMC6814625 DOI: 10.18632/aging.102270] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 09/05/2019] [Indexed: 01/08/2023]
Abstract
The relationship between aging and restenosis are unclear. The purposes of this study were to investigate the possible pathological role and mechanism of aging on formation of restenosis. Our data indicated that cell proliferation and migration of the oxidative stress-induced senescent vascular smooth muscle cells were obviously desensitized to stimulation by platelet-derived growth factor (PDGF)-BB, which may have been caused by suppression of promoter activity, transcription, translation, and activation levels of PDGF receptor (PDGFR)-β. The analyzed data obtained from the binding array of transcription factors (TFs) showed that binding levels of eighteen TFs on the PDGFR-β promoter region (-523 to -1) were significantly lower in senescent cells compared to those of non-senescent cells. Among these TFs, the bioinformatics prediction suggested that the putative binding sites of ten TFs were found in this promoter region. Of these, transcriptional levels of seven TFs were markedly reduced in senescent cells. The clinical data showed that the proportion of restenosis was relatively lower in the older group than that in the younger group. Our study results suggested that a PDGFR-β-mediated pathway was suppressed in aging cells, and our clinical data showed that age and the vascular status were slightly negatively correlated in overall participants.
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Affiliation(s)
- Chun-Hsu Pan
- School of Pharmacy, Taipei Medical University, Taipei 11031, Taiwan
| | - Chang-Jui Chen
- Department of Pharmacy, Taipei Medical University Hospital, Taipei 11031, Taiwan
| | - Chun-Ming Shih
- Division of Cardiology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei 11031, Taiwan
| | - Ming-Fu Wang
- Department of Food and Nutrition, Providence University, Taichung 433, Taiwan
| | - Jie-Yu Wang
- School of Pharmacy, Taipei Medical University, Taipei 11031, Taiwan
| | - Chieh-Hsi Wu
- School of Pharmacy, Taipei Medical University, Taipei 11031, Taiwan
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11
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Lv F, Wan Y, Chen Y, Pei L, Luo D, Fan G, Luo M, Xu D, Wang H. Prenatal Dexamethasone Exposure Induced Ovarian Developmental Toxicity and Transgenerational Effect in Rat Offspring. Endocrinology 2018; 159:1401-1415. [PMID: 29370380 DOI: 10.1210/en.2018-00044] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 01/12/2018] [Indexed: 02/06/2023]
Abstract
Prenatal dexamethasone exposure (PDE) induces multiorgan developmental toxicities in offspring. Here we verified the transgenerational inheritance effect of ovarian developmental toxicity by PDE and explored its intrauterine programming mechanism. Pregnant rats subcutaneously received 0.2 mg/kg/d dexamethasone from gestational day (GD) 9 to GD20. A subgroup was euthanized for fetuses on GD20, and the other group went on to spontaneous labor to produce F1 offspring. The adult F1 females were mated with normal males to produce the F2 and F3 generations. The PDE fetal rats exhibited ovarian mitochondrial structural abnormalities, decreased serum estradiol (E2) levels, and lower expression levels of ovarian steroidogenic factor 1 (SF1), steroidal synthetases, and insulinlike growth factor 1 (IGF1). On postnatal week (PW) 6 and PW12, the PDE F1 offspring showed altered reproductive behavior and ovarian morphology. The serum E2 level and ovarian expression of SF1, steroidal synthetases, and IGF1 were also decreased. The adult F3 offspring showed alterations in reproductive phenotype and ovarian IGF1, SF1, and steroidal synthetase expression similar to those of F1. PDE induces ovarian developmental toxicity and transgenerational inheritance effects. The mechanism by which this toxicity occurs may be related to PDE-induced low-functional programming of fetal ovarian IGF1/SF1 and steroidal synthetases.
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Affiliation(s)
- Feng Lv
- Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Yang Wan
- Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Yunxi Chen
- Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Linguo Pei
- Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Daji Luo
- Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan, China
| | - Guanlan Fan
- Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Mengcheng Luo
- Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan, China
| | - Dan Xu
- Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
- Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan, China
| | - Hui Wang
- Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
- Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan, China
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12
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Abstract
Reactive oxygen species (ROS) and oxidative stress have long been linked to aging and diseases prominent in the elderly such as hypertension, atherosclerosis, diabetes and atrial fibrillation (AF). NADPH oxidases (Nox) are a major source of ROS in the vasculature and are key players in mediating redox signalling under physiological and pathophysiological conditions. In this review, we focus on the Nox-mediated ROS signalling pathways involved in the regulation of 'longevity genes' and recapitulate their role in age-associated vascular changes and in the development of age-related cardiovascular diseases (CVDs). This review is predicated on burgeoning knowledge that Nox-derived ROS propagate tightly regulated yet varied signalling pathways, which, at the cellular level, may lead to diminished repair, the aging process and predisposition to CVDs. In addition, we briefly describe emerging Nox therapies and their potential in improving the health of the elderly population.
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13
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Natsume-Kitatani Y, Mamitsuka H. Classification of Promoters Based on the Combination of Core Promoter Elements Exhibits Different Histone Modification Patterns. PLoS One 2016; 11:e0151917. [PMID: 27003446 PMCID: PMC4803293 DOI: 10.1371/journal.pone.0151917] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 03/07/2016] [Indexed: 11/18/2022] Open
Abstract
Four different histones (H2A, H2B, H3, and H4; two subunits each) constitute a histone octamer, around which DNA wraps to form histone-DNA complexes called nucleosomes. Amino acid residues in each histone are occasionally modified, resulting in several biological effects, including differential regulation of transcription. Core promoters that encompass the transcription start site have well-conserved DNA motifs, including the initiator (Inr), TATA box, and DPE, which are collectively called the core promoter elements (CPEs). In this study, we systematically studied the associations between the CPEs and histone modifications by integrating the Drosophila Core Promoter Database and time-series ChIP-seq data for histone modifications (H3K4me3, H3K27ac, and H3K27me3) during development in Drosophila melanogaster via the modENCODE project. We classified 96 core promoters into four groups based on the presence or absence of the TATA box or DPE, calculated the histone modification ratio at the core promoter region, and transcribed region for each core promoter. We found that the histone modifications in TATA-less groups were static during development and that the core promoters could be clearly divided into three types: i) core promoters with continuous active marks (H3K4me3 and H3K27ac), ii) core promoters with a continuous inactive mark (H3K27me3) and occasional active marks, and iii) core promoters with occasional histone modifications. Linear regression analysis and non-linear regression by random forest showed that the TATA-containing groups included core promoters without histone modifications, for which the measured RNA expression values were not predictable accurately from the histone modification status. DPE-containing groups had a higher relative frequency of H3K27me3 in both the core promoter region and transcribed region. In summary, our analysis showed that there was a systematic link between the existence of the CPEs and the dynamics, frequency and influence on transcriptional activity of histone modifications.
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Affiliation(s)
- Yayoi Natsume-Kitatani
- Japan Science and Technology Agency, PRESTO (Precursory Research for Embryonic Science and Technology), Saitama, Japan
- * E-mail:
| | - Hiroshi Mamitsuka
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Kyoto, Japan
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14
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Abstract
The predominant function of the tumor suppressor p53 is transcriptional regulation. It is generally accepted that p53-dependent transcriptional activation occurs by binding to a specific recognition site in promoters of target genes. Additionally, several models for p53-dependent transcriptional repression have been postulated. Here, we evaluate these models based on a computational meta-analysis of genome-wide data. Surprisingly, several major models of p53-dependent gene regulation are implausible. Meta-analysis of large-scale data is unable to confirm reports on directly repressed p53 target genes and falsifies models of direct repression. This notion is supported by experimental re-analysis of representative genes reported as directly repressed by p53. Therefore, p53 is not a direct repressor of transcription, but solely activates its target genes. Moreover, models based on interference of p53 with activating transcription factors as well as models based on the function of ncRNAs are also not supported by the meta-analysis. As an alternative to models of direct repression, the meta-analysis leads to the conclusion that p53 represses transcription indirectly by activation of the p53-p21-DREAM/RB pathway.
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Key Words
- CDE, cell cycle-dependent element
- CDKN1A
- CHR, cell cycle genes homology region
- ChIP, chromatin immunoprecipitation
- DREAM complex
- DREAM, DP, RB-like, E2F4, and MuvB complex
- E2F/RB complex
- HPV, human papilloma virus
- NF-Y, Nuclear factor Y
- cdk, cyclin-dependent kinase
- genome-wide meta-analysis
- p53
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Affiliation(s)
- Martin Fischer
- a Molecular Oncology; Medical School ; University of Leipzig ; Leipzig , Germany
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15
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Liu K, Ying Z, Qi X, Shi Y, Tang Q. MicroRNA-1 regulates the proliferation of vascular smooth muscle cells by targeting insulin-like growth factor 1. Int J Mol Med 2015; 36:817-24. [PMID: 26166810 DOI: 10.3892/ijmm.2015.2277] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 05/29/2015] [Indexed: 11/06/2022] Open
Abstract
The aim of this study was to investigate the role of microRNAs (miRNAs or miRs) in vascular smooth muscle cell (VSMC) proliferation and to elucidate the underlying molecular mechanisms. In a previous study, using microarray analysis, differentially expressed miRNAs were identified in primary VSMCs isolated from the medial layer of the thoracic aorta obtained from spontaneously hypertensive rats (SHRs) and Wistar Kyoto (WKY) rats. Among others, miR-1 was identified to be downregulated in VSMCs from SHRs. Thus, in the present study, we focused on miR-1, the downregulation of which was confirmed by RT-qPCR and western blot analysis in VSMCs isolated from SHRs. We identified insulin-like growth factor 1 (IGF1) as a potential target gene of miR-1, and we subsequently validated IGF1 as a target gene of miR-1 by luciferase assay. The results revealed that the exogenous overexpression of miR-1 significantly suppressed the expression of IGF1. Additionally, we demonstrated that the downregulation of IGF1 by the introduction of miR-1 attenuated the proliferation of the VSMCs, suggesting that IGF1 is a target gene of miR-1 and that the effects of miR-1 are mediated through IGF1. In conclusion, the findings of our study demonstrate that miR-1 is significantly downregulated in VSMCs and that it is an important regulator of cell proliferation. Therefore, IGF1 may be involved in the regulation of VSMC proliferation by targeting miR-1.
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Affiliation(s)
- Kun Liu
- Department of Vascular Medicine, Peking University Shougang Hospital, Beijing, P.R. China
| | - Zhang Ying
- Department of Cardiology, the First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, P.R. China
| | - Xia Qi
- Transfusion Medicine Section, Department of Clinical Laboratory of Dalian Medical University, Dalian, Liaoning, P.R. China
| | - Ying Shi
- Beijing Youan Hospital, Beijing, P.R. China
| | - Qiang Tang
- Department of Vascular Medicine, Peking University Shougang Hospital, Beijing, P.R. China
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16
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Grimaldi V, Vietri MT, Schiano C, Picascia A, De Pascale MR, Fiorito C, Casamassimi A, Napoli C. Epigenetic reprogramming in atherosclerosis. Curr Atheroscler Rep 2015; 17:476. [PMID: 25433555 DOI: 10.1007/s11883-014-0476-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Recent data support the involvement of epigenetic alterations in the pathogenesis of atherosclerosis. The most widely investigated epigenetic mechanism is DNA methylation although also histone code changes occur during the diverse steps of atherosclerosis, such as endothelial cell proliferation, vascular smooth muscle cell (SMC) differentiation, and inflammatory pathway activation. In this review, we focus on the main genes that are epigenetically modified during the atherogenic process, particularly nitric oxide synthase (NOS), estrogen receptors (ERs), collagen type XV alpha 1 (COL15A1), vascular endothelial growth factor receptor (VEGFR), and ten-eleven translocation (TET), which are involved in endothelial dysfunction; gamma interferon (IFN-γ), forkhead box p3 (FOXP3), and tumor necrosis factor-α (TNF-α), associated with atherosclerotic inflammatory process; and p66shc, lectin-like oxLDL receptor (LOX1), and apolipoprotein E (APOE) genes, which are regulated by high cholesterol and homocysteine (Hcy) levels. Furthermore, we also discuss the role of non-coding RNAs (ncRNA) in atherosclerosis. NcRNAs are involved in epigenetic regulation of endothelial function, SMC proliferation, cholesterol synthesis, lipid metabolism, and inflammatory response.
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Affiliation(s)
- Vincenzo Grimaldi
- U.O.C. Immunohematology, Transfusion Medicine and Transplant Immunology [SIMT], Regional Reference Laboratory of Transplant Immunology [LIT], Azienda Universitaria Policlinico (AOU), Second University of Naples (SUN), Piazza L. Miraglia 2, 80138, Naples, Italy,
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17
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Liu J, Wang Y, Wu Y, Ni B, Liang Z. Sodium butyrate promotes the differentiation of rat bone marrow mesenchymal stem cells to smooth muscle cells through histone acetylation. PLoS One 2014; 9:e116183. [PMID: 25548915 PMCID: PMC4280132 DOI: 10.1371/journal.pone.0116183] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 12/04/2014] [Indexed: 12/27/2022] Open
Abstract
Establishing an effective method to improve stem cell differentiation is crucial in stem cell transplantation. Here we aimed to explore whether and how sodium butyrate (NaB) induces rat bone marrow mesenchymal stem cells (MSCs) to differentiate into bladder smooth muscle cells (SMCs). We found that NaB significantly suppressed MSC proliferation and promoted MSCs differentiation into SMCs, as evidenced by the enhanced expression of SMC specific genes in the MSCs. Co-culturing the MSCs with SMCs in a transwell system promoted the differentiation of MSCs into SMCs. NaB again promoted MSC differentiation in this system. Furthermore, NaB enhanced the acetylation of SMC gene-associated H3K9 and H4, and decreased the expression of HDAC2 and down-regulated the recruitment of HDAC2 to the promoter regions of SMC specific genes. Finally, we found that NaB significantly promoted MSC depolarization and increased the intracellular calcium level of MSCs upon carbachol stimulation. These results demonstrated that NaB effectively promotes MSC differentiation into SMCs, possibly by the marked inhibition of HDAC2 expression and disassociation of HDAC2 recruitment to SMC specific genes in MSCs, which further induces high levels of H3K9ace and H4ace and the enhanced expression of target genes, and this strategy could potentially be applied in clinical tissue engineering and cell transplantation.
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Affiliation(s)
- Jingxia Liu
- Department of Gynecology and Obstetrics, Southwest Hospital, Third Military Medical University, Chongqing 400038, PR China
| | - Yanzhou Wang
- Department of Gynecology and Obstetrics, Southwest Hospital, Third Military Medical University, Chongqing 400038, PR China
| | - Yuzhang Wu
- Institutions of Immunology, PLA, Third Military Medical University, Chongqing 400038, PR China
| | - Bing Ni
- Institutions of Immunology, PLA, Third Military Medical University, Chongqing 400038, PR China
| | - Zhiqing Liang
- Department of Gynecology and Obstetrics, Southwest Hospital, Third Military Medical University, Chongqing 400038, PR China
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18
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Tucka J, Yu H, Gray K, Figg N, Maguire J, Lam B, Bennett M, Littlewood T. Akt1 regulates vascular smooth muscle cell apoptosis through FoxO3a and Apaf1 and protects against arterial remodeling and atherosclerosis. Arterioscler Thromb Vasc Biol 2014; 34:2421-8. [PMID: 25234814 DOI: 10.1161/atvbaha.114.304284] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
OBJECTIVE Vascular smooth muscle cell (VSMC) apoptosis occurs at low levels in atherosclerotic plaques and in vessel remodeling; however, the consequences and mediators of these levels are not known. Akt1 protects against VSMC apoptosis largely through inactivating target proteins such as forkhead class O transcription factor 3a (FoxO3a), but Akt1 signaling is reduced and FoxO3a activity is increased in human atherosclerosis. We therefore sought to determine whether inhibition of VSMC apoptosis via Akt1 activation regulates vessel remodeling and atherogenesis and to identify FoxO3a target proteins that mediate VSMC apoptosis. APPROACH AND RESULTS We generated mice that express an Akt1 protein that can be activated specifically in arterial VSMCs. Akt1 activation did not affect normal arteries, but inhibited VSMC apoptosis and negative remodeling after carotid ligation, indicating that VSMC apoptosis is a major determinant of vessel caliber after changes in flow. Akt1 activation inhibited VSMC apoptosis during atherogenesis and increased relative fibrous cap area in plaques. Microarray studies identified multiple FoxO3a-regulated genes involved in VSMC apoptosis, including apoptotic protease activating factor 1 as a novel target. Apoptotic protease activating factor 1 mediated the proapoptotic activity of FoxO3a, was increased in human atherosclerosis, but reduced by Akt1 activity in vivo. CONCLUSIONS Akt1 is a major regulator of VSMC survival in vivo during vessel remodeling and atherogenesis, mediated in large part through inhibition of FoxO3a and its downstream genes, including apoptotic protease activating factor 1. Our data suggest that even the low-level VSMC apoptosis seen during changes in flow determines vessel wall structure and promotes fibrous cap thinning during atherogenesis.
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Affiliation(s)
- Joanna Tucka
- From the Divisions of Cardiovascular Medicine (J.T., H.Y., K.G., N.F., M.B., T.L.), Clinical Pharmacology (J.M.), and Metabolic Research Laboratories (B.L.), University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom; and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom (T.L.)
| | - Haixiang Yu
- From the Divisions of Cardiovascular Medicine (J.T., H.Y., K.G., N.F., M.B., T.L.), Clinical Pharmacology (J.M.), and Metabolic Research Laboratories (B.L.), University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom; and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom (T.L.)
| | - Kelly Gray
- From the Divisions of Cardiovascular Medicine (J.T., H.Y., K.G., N.F., M.B., T.L.), Clinical Pharmacology (J.M.), and Metabolic Research Laboratories (B.L.), University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom; and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom (T.L.)
| | - Nichola Figg
- From the Divisions of Cardiovascular Medicine (J.T., H.Y., K.G., N.F., M.B., T.L.), Clinical Pharmacology (J.M.), and Metabolic Research Laboratories (B.L.), University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom; and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom (T.L.)
| | - Janet Maguire
- From the Divisions of Cardiovascular Medicine (J.T., H.Y., K.G., N.F., M.B., T.L.), Clinical Pharmacology (J.M.), and Metabolic Research Laboratories (B.L.), University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom; and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom (T.L.)
| | - Brian Lam
- From the Divisions of Cardiovascular Medicine (J.T., H.Y., K.G., N.F., M.B., T.L.), Clinical Pharmacology (J.M.), and Metabolic Research Laboratories (B.L.), University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom; and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom (T.L.)
| | - Martin Bennett
- From the Divisions of Cardiovascular Medicine (J.T., H.Y., K.G., N.F., M.B., T.L.), Clinical Pharmacology (J.M.), and Metabolic Research Laboratories (B.L.), University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom; and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom (T.L.)
| | - Trevor Littlewood
- From the Divisions of Cardiovascular Medicine (J.T., H.Y., K.G., N.F., M.B., T.L.), Clinical Pharmacology (J.M.), and Metabolic Research Laboratories (B.L.), University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom; and Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom (T.L.).
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19
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Zhang D, Cui Y, Niu L, Xu X, Tian K, Young CYF, Lou H, Yuan H. Regulation of SOD2 and β-arrestin1 by interleukin-6 contributes to the increase of IGF-1R expression in docetaxel resistant prostate cancer cells. Eur J Cell Biol 2014; 93:289-98. [PMID: 24939178 DOI: 10.1016/j.ejcb.2014.05.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 04/29/2014] [Accepted: 05/21/2014] [Indexed: 01/07/2023] Open
Abstract
Although several mechanisms behind resistance to docetaxel in castration-refractory prostate cancer (CRPC) have been investigated, molecular determinants of evolved resistance are still not entirely understood. Proteomics-based analysis in this study revealed that SOD2, associated with downregulation of reactive oxygen species (ROS), was significantly up-regulated in docetaxel-resistant (PC3/Doc) cells if compared to sensitive cells, and the expression of redox-regulated genes such as IGF-1R, CXCR4, and BCL2 was increased as well. Forced expression of SOD2 in sensitive cells led to the increase of IGF-1R and association with drug resistance, whereas silencing of SOD2 resulted in the decrease of IGF-1R at the protein level in resistant cells. Further study revealed that SOD2 acted as a negative regulator of β-arrestin1 that is an important adaptor responsible for degradation of IGF-1R via the changes in ROS, as evidenced by observations that an antioxidant agent substantially attenuated β-arrestin1 expression in vitro and in vivo. Finally, we found that blocking of IL6 that was up-regulated in resistant cells resulted in attenuation of SOD2 and STAT3, and simultaneously in increased expression of β-arrestin1. The modulation consequently led to the decreased IGF-1R at both protein and transcription levels. Together, our data provide a novel explanation that high level of IL6 stimulated SOD2 expression that, at least partially, contributed to the low level of ROS that would likely result in a sustained increase in the expression of IGF-1R through abolishment of β-arrestin1 in docetaxel resistant cells.
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Affiliation(s)
- Denglu Zhang
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan 250012, China; Department of Natural Product Chemistry, Shandong University School of Pharmaceutical Sciences, Jinan 250012, China
| | - Yazhou Cui
- Key Laboratory for Biotech Drugs of the Ministry of Health, Shandong Academy of Medical Sciences, Jinan 250012, China
| | - Leilei Niu
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan 250012, China
| | - Xia Xu
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan 250012, China
| | - Keli Tian
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan 250012, China
| | - Charles Y F Young
- Department of Urology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Hongxiang Lou
- Department of Natural Product Chemistry, Shandong University School of Pharmaceutical Sciences, Jinan 250012, China
| | - Huiqing Yuan
- Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan 250012, China.
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20
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Othman EM, Hintzsche H, Stopper H. Signaling steps in the induction of genomic damage by insulin in colon and kidney cells. Free Radic Biol Med 2014; 68:247-57. [PMID: 24355212 DOI: 10.1016/j.freeradbiomed.2013.12.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 11/20/2013] [Accepted: 12/09/2013] [Indexed: 12/22/2022]
Abstract
Diabetes mellitus (DM), a disease with almost 350 million people affected worldwide, will be the seventh leading cause of death by 2030. Diabetic patients develop various types of complications, among them an increased rate of malignancies. Studies reported the strong correlation between DM and several cancer types, of which colon and kidney cancers are the most common. Hyperinsulinemia, the high insulin blood level characteristic of early diabetes type 2, was identified as a risk factor for cancer development. In previous studies, we showed that an elevated insulin level can induce oxidative stress, resulting in DNA damage in colon cells in vitro and in kidney cells in vitro and in vivo. In the present study, we elucidate the signaling pathway of insulin-mediated genotoxicity, which is effective through oxidative stress induction in colon and kidney. The signaling mechanism is starting by phosphorylation of the insulin and insulin-like growth factor-1 receptors, followed by activation of phosphatidylinositide 3-kinase (PI3K), which in turn activates AKT. Subsequently, mitochondria and nicotinamide adenine dinucleotide phosphate oxidase (NADPH) isoforms (Nox1 and Nox4 in colon and kidney, respectively) are activated for reactive oxygen species (ROS) production, and the resulting excess ROS can attack the DNA, causing DNA oxidation. We conclude that hyperinsulinemia represents an important risk factor for cancer initiation or progression as well as a target for cancer prevention in diabetic patients.
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Affiliation(s)
- Eman Maher Othman
- Institute of Pharmacology and Toxicology, University of Wuerzburg, D-97078 Wuerzburg, Germany; Department of Analytical Chemistry, Faculty of Pharmacy, University of El-Minia, 61519 El-Minia, Egypt
| | - Henning Hintzsche
- Institute of Pharmacology and Toxicology, University of Wuerzburg, D-97078 Wuerzburg, Germany
| | - Helga Stopper
- Institute of Pharmacology and Toxicology, University of Wuerzburg, D-97078 Wuerzburg, Germany.
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Abstract
Epigenetics involve heritable and acquired changes in gene transcription that occur independently of the DNA sequence. Epigenetic mechanisms constitute a hierarchic upper-level of transcriptional control through complex modifications of chromosomal components and nuclear structures. These modifications include, for example, DNA methylation or post-translational modifications of core histones; they are mediated by various chromatin-modifying enzymes; and ultimately they define the accessibility of a transcriptional complex to its target DNA. Integrating epigenetic mechanisms into the pathophysiologic concept of complex and multifactorial diseases such as atherosclerosis may significantly enhance our understanding of related mechanisms and provide promising therapeutic approaches. Although still in its infancy, intriguing scientific progress has begun to elucidate the role of epigenetic mechanisms in vascular biology, particularly in the control of smooth muscle cell phenotypes. In this review, we will summarize epigenetic pathways in smooth muscle cells, focusing on mechanisms involved in the regulation of vascular remodeling.
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22
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Findeisen HM, Kahles FK, Bruemmer D. Epigenetic regulation of vascular smooth muscle cell function in atherosclerosis. Curr Atheroscler Rep 2013; 15:319. [PMID: 23630979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Epigenetics involve heritable and acquired changes in gene transcription that occur independently of the DNA sequence. Epigenetic mechanisms constitute a hierarchic upper-level of transcriptional control through complex modifications of chromosomal components and nuclear structures. These modifications include, for example, DNA methylation or post-translational modifications of core histones; they are mediated by various chromatin-modifying enzymes; and ultimately they define the accessibility of a transcriptional complex to its target DNA. Integrating epigenetic mechanisms into the pathophysiologic concept of complex and multifactorial diseases such as atherosclerosis may significantly enhance our understanding of related mechanisms and provide promising therapeutic approaches. Although still in its infancy, intriguing scientific progress has begun to elucidate the role of epigenetic mechanisms in vascular biology, particularly in the control of smooth muscle cell phenotypes. In this review, we will summarize epigenetic pathways in smooth muscle cells, focusing on mechanisms involved in the regulation of vascular remodeling.
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Affiliation(s)
- Hannes M Findeisen
- Department of Internal Medicine I-Cardiology, University Hospital Aachen, RWTH Aachen, Pauwelstr. 30, 52074 Aachen, Germany.
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23
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Wang Y, Zhang ZY, Chen XQ, Wang X, Cao H, Liu SW. Advanced glycation end products promote human aortic smooth muscle cell calcification in vitro via activating NF-κB and down-regulating IGF1R expression. Acta Pharmacol Sin 2013; 34:480-6. [PMID: 23416929 PMCID: PMC4002782 DOI: 10.1038/aps.2012.166] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2012] [Accepted: 11/14/2012] [Indexed: 02/07/2023] Open
Abstract
AIM To investigate the effects of advanced glycation end products (AGEs) on calcification in human aortic smooth muscle cells (HASMCs) in vitro and the underlying mechanisms. METHODS AGEs were artificially prepared. Calcification of HASMCs was induced by adding inorganic phosphate (Pi, 2 mmol/L) in the media, and observed with Alizarin red staining. The calcium content in the supernatant was measured using QuantiChrome Calcium Assay Kit. Expression of the related mRNAs and proteins was analyzed using real-time PCR and Western blot, respectively. Chromatin immunoprecipitation (ChIP) assay was used to detect the binding of NF-κB to the putative IGF1R promoter. RESULTS AGEs (100 μg/mL) significantly enhanced Pi-induced calcification and the levels of osteocalcin and Cbfα1 in HASMCs. Furthermore, the treatment decreased the expression of insulin-like growth factor 1 receptor (IGF1R). Over-expression of IGF1R in HASMCs suppressed the AGEs-induced increase in calcium deposition. When IGF1R expression was knocked down in HASMCs, AGEs did not enhance the calcium deposition. Meanwhile, AGEs time-dependently decreased the amounts of IκBα and Flag-tagged p65 in the cytoplasmic extracts, and increased the amount of nuclear p65 in HASMCs. In the presence of NF-κB inhibitor PDTC (50 μmol/L), the AGEs-induced increase in calcium deposition was blocked. Over-expression of p65 significantly enhanced Pi-induced mineralization, but suppressed IGF1R mRNA level. Knockdown of p65 suppressed the AGEs-induced increase in calcium deposition, and rescued the IGF1R expression. The ChIP analysis revealed that NF-κB bound the putative IGF1R promoter at position -230 to -219 bp. The inhibition of IGF1R by NF-κB was abolished when IGF1R reporter plasmid contained mutated binding sequence for NF-κB or an NF-κB reporter vector. CONCLUSION The results demonstrate that AGEs promote calcification of human aortic smooth muscle cells in vitro via activation of NF-κB and down-regulation of IGF1R expression.
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MESH Headings
- Aorta/metabolism
- Aorta/pathology
- Calcium/metabolism
- Cells, Cultured
- Core Binding Factor Alpha 1 Subunit/genetics
- Core Binding Factor Alpha 1 Subunit/metabolism
- Down-Regulation/genetics
- Glycation End Products, Advanced/genetics
- Glycation End Products, Advanced/metabolism
- Humans
- I-kappa B Proteins/genetics
- I-kappa B Proteins/metabolism
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- NF-KappaB Inhibitor alpha
- NF-kappa B/genetics
- NF-kappa B/metabolism
- Promoter Regions, Genetic/genetics
- RNA, Messenger/genetics
- Receptor, IGF Type 1/antagonists & inhibitors
- Receptor, IGF Type 1/genetics
- Receptor, IGF Type 1/metabolism
- Vascular Calcification/genetics
- Vascular Calcification/metabolism
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Affiliation(s)
- Yi Wang
- Department of Cardiology, Shanghai First People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200080, China
| | - Zhen-yu Zhang
- Department of Cardiology, Shanghai First People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200080, China
| | - Xiao-qing Chen
- Department of Cardiology, Shanghai First People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200080, China
| | - Xiang Wang
- Department of Cardiology, Shanghai First People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200080, China
| | - Heng Cao
- Department of Cardiology, Shanghai First People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200080, China
| | - Shao-wen Liu
- Department of Cardiology, Shanghai First People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200080, China
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24
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Kadhim M, Salomaa S, Wright E, Hildebrandt G, Belyakov OV, Prise KM, Little MP. Non-targeted effects of ionising radiation--implications for low dose risk. Mutat Res 2013; 752:84-98. [PMID: 23262375 PMCID: PMC4091999 DOI: 10.1016/j.mrrev.2012.12.001] [Citation(s) in RCA: 159] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 12/03/2012] [Accepted: 12/04/2012] [Indexed: 12/17/2022]
Abstract
Non-DNA targeted effects of ionising radiation, which include genomic instability, and a variety of bystander effects including abscopal effects and bystander mediated adaptive response, have raised concerns about the magnitude of low-dose radiation risk. Genomic instability, bystander effects and adaptive responses are powered by fundamental, but not clearly understood systems that maintain tissue homeostasis. Despite excellent research in this field by various groups, there are still gaps in our understanding of the likely mechanisms associated with non-DNA targeted effects, particularly with respect to systemic (human health) consequences at low and intermediate doses of ionising radiation. Other outstanding questions include links between the different non-targeted responses and the variations in response observed between individuals and cell lines, possibly a function of genetic background. Furthermore, it is still not known what the initial target and early interactions in cells are that give rise to non-targeted responses in neighbouring or descendant cells. This paper provides a commentary on the current state of the field as a result of the non-targeted effects of ionising radiation (NOTE) Integrated Project funded by the European Union. Here we critically examine the evidence for non-targeted effects, discuss apparently contradictory results and consider implications for low-dose radiation health effects.
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Affiliation(s)
- Munira Kadhim
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, UK.
| | - Sisko Salomaa
- STUK - Radiation and Nuclear Safety Authority, P.O. Box 14, 00881 Helsinki, Finland
| | - Eric Wright
- School of Medicine, College of Medicine, Dentistry and Nursing, University of Dundee, Nethergate, Dundee, DD1 4HN, Scotland, UK
| | - Guido Hildebrandt
- Department of Radiotherapy and Radiation Oncology, University of Rostock, Südring 75, 18051 Rostock, Germany
| | - Oleg V Belyakov
- Hevesy Laboratory, Center for Nuclear Technologies, Technical University of Denmark, 4000 Roskilde, Denmark
| | | | - Mark P Little
- Radiation Epidemiology Branch, National Cancer Institute, 6120 Executive Boulevard, Rockville, MD 20852, USA
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Global effect of inauhzin on human p53-responsive transcriptome. PLoS One 2012; 7:e52172. [PMID: 23284922 PMCID: PMC3528779 DOI: 10.1371/journal.pone.0052172] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 11/15/2012] [Indexed: 12/19/2022] Open
Abstract
Background Previously, we reported that Inauhzin (INZ) induces p53 activity and suppresses tumor growth by inhibiting Sirt1. However, it remains unknown whether INZ may globally affect p53-dependent gene expression or not. Herein, we have conducted microarray and real-time PCR analyses of gene expression to determine the global effect of INZ on human p53-responsive transcriptome. Methodology/Principal Findings In this study, we conducted microarray analysis followed by PCR validation of general gene expression in HCT116p53+/+ and HCT116p53−/− cells treated with or without INZ. Microarray data showed that 324 genes were up-regulated by ≥2.3-fold and 266 genes were down-regulated by ≥2-fold in response to INZ treatment in a p53-dependent manner. GO analysis for these genes further revealed that INZ affects several biological processes, including apoptosis (GO:0006915), cell cycle (GO:0007049), immune system process (GO:0002376), and cell adhesion (GO:0007155), which are in line with p53 functions in cells. Also, pathway and STRING analyses of these genes indicated that the p53-signaling pathway is the most significant pathway responsive to INZ treatment as predicted, since a number of these p53 target genes have been previously reported and some of them were validated by RT-qPCR. Finally, among the 9 tested and highly expressed genes, ACBD4, APOBEC3C, and FLJ14327 could be novel p53 target genes, for they were up-regulated by INZ in HCT116p53+/+ cells, but not in HCT116p53−/− cells. Conclusions/Significance From our whole genome microarray analysis followed by validation with RT-qPCR, we found that INZ can indeed induce the expression of p53 target genes at a larger scale or globally. Our findings not only verify that INZ indeed activates the p53 signaling pathway, but also provide useful information for identifying novel INZ and/or p53 targets. The global effect of INZ on human p53-responsive transcriptome could also be instrumental to the future design of INZ clinical trials.
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Upregulation of the E3 ligase NEDD4-1 by oxidative stress degrades IGF-1 receptor protein in neurodegeneration. J Neurosci 2012; 32:10971-81. [PMID: 22875931 DOI: 10.1523/jneurosci.1836-12.2012] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The importance of ubiquitin E3 ligases in neurodegeneration is being increasingly recognized. The crucial role of NEDD4-1 in neural development is well appreciated; however, its role in neurodegeneration remains unexplored. Herein, we report increased NEDD4-1 expression in the degenerated tissues of several major neurodegenerative diseases. Moreover, its expression is upregulated in cultured neurons in response to various neurotoxins, including zinc and hydrogen superoxide, via transcriptional activation likely mediated by the reactive oxygen species (ROS)-responsive FOXM1B. Reduced protein levels of the insulin-like growth factor receptor (IGF-1Rβ) were observed as a consequence of upregulated NEDD4-1 via the ubiquitin-proteasome system. Overexpression of a familial mutant form of superoxide dismutase 1 (SOD1) (G93A) in neuroblastoma cells resulted in a similar reduction of IGF-1Rβ protein. This inverse correlation between NEDD4-1 and IGF-1Rβ was also observed in the cortex and spinal cords of mutant (G93A) SOD1 transgenic mice at a presymptomatic age, which was similarly induced by in vivo-administered zinc in wild-type C57BL/6 mice. Furthermore, histochemistry reveals markedly increased NEDD4-1 immunoreactivity in the degenerating/degenerated motor neurons in the lumbar anterior horn of the spinal cord, suggesting a direct causative role for NEDD4-1 in neurodegeneration. Indeed, downregulation of NEDD4-1 by shRNA or overexpression of a catalytically inactive form rescued neurons from zinc-induced cell death. Similarly, neurons with a NEDD4-1 haplotype are more resistant to apoptosis, largely due to expression of higher levels of IGF-1Rβ.Together, our work identifies a novel molecular mechanism for ROS-upregulated NEDD4-1 and the subsequently reduced IGF-1Rβ signaling in neurodegeneration.
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Chua HH, Chiu HY, Lin SJ, Weng PL, Lin JH, Wu SW, Tsai SC, Tsai CH. p53 and Sp1 cooperate to regulate the expression of Epstein-Barr viral Zta protein. J Med Virol 2012; 84:1279-88. [PMID: 22711357 DOI: 10.1002/jmv.23316] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Epstein-Barr virus (EBV) belongs to the gammaherpesvirus family. To produce infectious progeny, EBV reactivates from latency into the lytic cycle by expressing the determinative lytic transactivator, Zta. In the presence of histone deacetylase inhibitor (HDACi), p53 is a prerequisite for the initiation of the EBV lytic cycle by facilitating the expression of Zta. In this study, a serial mutational analysis of Zta promoter (Zp) indicated an important role for the ZID element in responding to HDACi induction and p53 binds to this ZID element together with Sp1, a universal transcription factor. Abolition of the DNA-binding ability of Sp1 reduces the inducibility of ZID by HDACi and also reduces the amount of p53 binding to ZID. Finally, it was shown that EBV in p53-positive-lymphoblastoid cell lines (LCLs) can enter into the lytic cycle spontaneously; however, knockdown of p53 in LCLs leads to retardation of EBV reactivation.
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Affiliation(s)
- Huey-Huey Chua
- College of Medicine, Graduate Institute of Microbiology, National Taiwan University, Taipei, Taiwan
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28
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Wang JC, Bennett M. Aging and atherosclerosis: mechanisms, functional consequences, and potential therapeutics for cellular senescence. Circ Res 2012; 111:245-59. [PMID: 22773427 DOI: 10.1161/circresaha.111.261388] [Citation(s) in RCA: 585] [Impact Index Per Article: 48.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Atherosclerosis is classed as a disease of aging, such that increasing age is an independent risk factor for the development of atherosclerosis. Atherosclerosis is also associated with premature biological aging, as atherosclerotic plaques show evidence of cellular senescence characterized by reduced cell proliferation, irreversible growth arrest and apoptosis, elevated DNA damage, epigenetic modifications, and telomere shortening and dysfunction. Not only is cellular senescence associated with atherosclerosis, there is growing evidence that cellular senescence promotes atherosclerosis. This review examines the pathology of normal vascular aging, the evidence for cellular senescence in atherosclerosis, the mechanisms underlying cellular senescence including reactive oxygen species, replication exhaustion and DNA damage, the functional consequences of vascular cell senescence, and the possibility that preventing accelerated cellular senescence is a therapeutic target in atherosclerosis.
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Affiliation(s)
- Julie C Wang
- Division of Cardiovascular Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK
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29
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Bennett M, Yu H, Clarke M. Signalling from dead cells drives inflammation and vessel remodelling. Vascul Pharmacol 2012; 56:187-92. [PMID: 22306421 DOI: 10.1016/j.vph.2012.01.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 01/17/2012] [Accepted: 01/21/2012] [Indexed: 11/16/2022]
Abstract
Death of vascular smooth muscle cells (VSMCs) has been demonstrated in vessel development and in disease, most notably in atherosclerosis, but also after injury and remodelling. VSMC death promotes multiple features of vulnerable plaques, but also induces features of normal vessel ageing and cystic medial necrosis, including loss of VSMCs, elastin fragmentation and loss, increased glycosaminoglycans and speckled calcification. VSMC apoptosis in the absence of efficient phagocytosis also produces inflammation due to secondary necrosis; in contrast, VSMC apoptosis in normal vessels can be silent. We have investigated the consequences of VSMC apoptosis in both disease and during vessel remodelling. We find that VSMCs release specific cytokines dependent upon the mode of cell death; IL-1β predominates during apoptosis, whilst IL-1α predominates during necrosis. Both IL-1α and β promote release of further cytokines from adjacent live cells, in particular IL-6 and MCP-1. The balance of cytokines results in pathology with differing compositions, including inflammation or neointima formation/vascular repair, via direct promotion of VSMC proliferation and migration. Thus, VSMC death can promote either pathology or repair, depending upon the context and cytokine signalling.
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Affiliation(s)
- Martin Bennett
- Division of Cardiovascular Medicine, University of Cambridge, Addenbrooke's Centre for Clinical Investigation, Addenbrooke's Hospital, Cambridge, United Kingdom.
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30
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Reinhardt HC, Schumacher B. The p53 network: cellular and systemic DNA damage responses in aging and cancer. Trends Genet 2012; 28:128-36. [PMID: 22265392 DOI: 10.1016/j.tig.2011.12.002] [Citation(s) in RCA: 327] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Revised: 12/12/2011] [Accepted: 12/12/2011] [Indexed: 12/16/2022]
Abstract
Genome instability contributes to cancer development and accelerates age-related pathologies as evidenced by a variety of congenital cancer susceptibility and progeroid syndromes that are caused by defects in genome maintenance mechanisms. DNA damage response (DDR) pathways that are mediated through the tumor suppressor p53 play an important role in the cell-intrinsic responses to genome instability, including a transient cell cycle arrest, senescence and apoptosis. Both senescence and apoptosis are powerful tumor-suppressive pathways preventing the uncontrolled proliferation of transformed cells. However, both pathways can potentially deplete stem and progenitor cell pools, thus promoting tissue degeneration and organ failure, which are both hallmarks of aging. p53 signaling is also involved in mediating non-cell-autonomous interactions with the innate immune system and in the systemic adjustments during the aging process. The network of p53 target genes thus functions as an important regulator of cancer prevention and aging.
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Affiliation(s)
- H Christian Reinhardt
- Cologne Excellence Cluster on Cellular Stress Response in Aging-Associated Diseases, University of Cologne, 50674 Cologne, Germany.
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31
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Ma Y, Cheng Q, Ren Z, Xu L, Zhao Y, Sun J, Hu S, Xiao W. Induction of IGF-1R expression by EGR-1 facilitates the growth of prostate cancer cells. Cancer Lett 2011; 317:150-6. [PMID: 22115966 DOI: 10.1016/j.canlet.2011.11.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2011] [Revised: 10/13/2011] [Accepted: 11/15/2011] [Indexed: 01/02/2023]
Abstract
The transcription factor Early Growth Response-1 (EGR-1) is overexpressed in human prostate tumors and contributes to prostate cancer progression through an unknown mechanism. Here we report that EGR-1 transcriptionally regulates the expression of insulin-like growth factor-1 receptor (IGF-1R), which is highly expressed in primary prostate cancer. We find that ectopic expression of EGR-1 causes increase in IGF-1R expression, while knockdown of EGR-1 leads to dramatically decrease in IGF-1R expression. Results from chromatin immunoprecipitation (ChIP) and reporter assay show that the EGR-1 directly binds to the human IGF-1R gene and triggers the target gene expression. EGR-1 activates Erk and Akt pathway through regulation of IGF-1R, and thus promote prostate cancer cell growth. Taken together, these results suggest that EGR-1 may stimulate prostate cancer cell growth through up-regulation of IGF-1R and indicate that down-regulation of EGR-1 could be an effective therapeutic approach against prostate cancer.
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Affiliation(s)
- Yang Ma
- Institute of Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
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32
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Rinn JL, Huarte M. To repress or not to repress: this is the guardian's question. Trends Cell Biol 2011; 21:344-53. [PMID: 21601459 DOI: 10.1016/j.tcb.2011.04.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 04/11/2011] [Accepted: 04/13/2011] [Indexed: 10/18/2022]
Abstract
p53 is possibly the most central tumor suppressor gene of our cells, integrating stress signals to activate a transcriptional program responsible for maintaining cellular homeostasis. Many of the downstream effects of p53 are a consequence of its activity as a transcription factor, resulting in the induction of multiple target genes. In addition to gene activation, however, gene repression is an essential part of the p53 cellular response. Despite extensive research efforts towards the elucidation of p53 functions, the molecular mechanisms and biological consequences of gene repression by p53 have not been studied extensively. We review our current knowledge of the mechanisms and biological consequences of p53 repression, with special attention to recently discovered mechanisms of repression that involve non-coding RNA molecules, an emerging aspect of regulation in the p53 cellular network.
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Affiliation(s)
- John L Rinn
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts, USA
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33
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Di Bartolo BA, Schoppet M, Mattar MZ, Rachner TD, Shanahan CM, Kavurma MM. Calcium and osteoprotegerin regulate IGF1R expression to inhibit vascular calcification. Cardiovasc Res 2011; 91:537-45. [DOI: 10.1093/cvr/cvr084] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
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34
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Zhou B, Margariti A, Zeng L, Xu Q. Role of histone deacetylases in vascular cell homeostasis and arteriosclerosis. Cardiovasc Res 2011; 90:413-20. [DOI: 10.1093/cvr/cvr003] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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35
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Li Y, Geng YJ. A potential role for insulin-like growth factor signaling in induction of pluripotent stem cell formation. Growth Horm IGF Res 2010; 20:391-398. [PMID: 20956084 DOI: 10.1016/j.ghir.2010.09.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Revised: 09/17/2010] [Accepted: 09/21/2010] [Indexed: 12/11/2022]
Abstract
Recent success in reprogramming somatic cells into induced pluripotent stem cells (iPS cells) with a cluster of nuclear transcription factors, such as Oct4, Sox2, Klf4, and c-myc, opens up a new era in regenerative medicine. However, reportedly poor efficiency and slow kinetics of the reprogramming process by viral transfection of the nuclear factors may create an obstacle that hampers clinical application of the iPS cell technology. Furthermore, the viral transfection may induce mutagenesis and raises the risk for cancer development. Hence, generation of iPS cells using a non-viral approach appears to be an important prerequisite for iPS cell-based regenerative medicine. Through its receptor/phosphoinositide 3-kinase (PI3-K) signaling pathway, insulin-like growth factor (IGF) plays a critical role in promotion of survival and proliferation in a diversity of cell types, including both embryonic and adult stem cells. In addition, IGF may enhance expression of reprogramming or surviving factors in reprogramming somatic cells. This review summarizes recent advances in IGF research and discusses the potential for IGF to act as a co-stimulatory factor for somatic cell reprogramming and iPS cell development. Currently available evidence from experimental animal and human studies highly suggests that IGF may contribute to reprogramming of somatic cells into iPS cell generation, and enhancement of iPS cell survival and growth, which will be instrumental in regenerative medicine.
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Affiliation(s)
- Yangxin Li
- Texas Heart Institute, Houston, TX 77030, USA.
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36
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Fernandez AZ, Siebel AL, El-Osta A. Atherogenic factors and their epigenetic relationships. Int J Vasc Med 2010; 2010:437809. [PMID: 21152193 PMCID: PMC2989709 DOI: 10.1155/2010/437809] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Accepted: 08/25/2010] [Indexed: 02/08/2023] Open
Abstract
Hypercholesterolemia, homocysteine, oxidative stress, and hyperglycemia have been recognized as the major risk factors for atherogenesis. Their impact on the physiology and biochemistry of vascular cells has been widely demonstrated for the last century. However, the recent discovery of the role of epigenetics in human disease has opened up a new field in the study of atherogenic factors. Thus, epigenetic tags in endothelial, smooth muscle, and immune cells seem to be differentially affected by similar atherogenic stimuli. This paper summarizes some recent works on expression of histone-modifying enzymes and DNA methylation directly linked to the presence of risk factors that could lead to the development or prevention of the atherosclerotic process.
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Affiliation(s)
- Ana Z. Fernandez
- Hemostasia and Vascular Genetics Laboratory, Biophysics and Biochemistry Center, Venezuelan Institute for Scientific Research IVIC, Carretera Panamericana km11, P.O. 26973, Caracas 1020, Venezuela
- Epigenetics in Human Health and Disease Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, VIC 3004, Australia
| | - Andrew L. Siebel
- Epigenetics in Human Health and Disease Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, VIC 3004, Australia
| | - Assam El-Osta
- Epigenetics in Human Health and Disease Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, VIC 3004, Australia
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Yu XY, Geng YJ, Liang JL, Lin QX, Lin SG, Zhang S, Li Y. High levels of glucose induce apoptosis in cardiomyocyte via epigenetic regulation of the insulin-like growth factor receptor. Exp Cell Res 2010; 316:2903-9. [PMID: 20633551 DOI: 10.1016/j.yexcr.2010.07.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Revised: 07/02/2010] [Accepted: 07/06/2010] [Indexed: 12/28/2022]
Abstract
Diabetic hyperglycemia result in cardiovascular complications, but the mechanisms by which high levels of glucose (HG) cause diabetic cardiomyopathy are not known. We investigate whether HG-induced repression of insulin-like growth factor 1 receptor (IGF-1R) mediated by epigenetic modifications is one potential mechanism. We found that HG resulted in decreased IGF-1 receptor (IGF-1R) mRNA levels, and IGF-1R protein when compared with H9C2 rat cardiomyocyte cells incubated in normal glucose. HG also induced apoptosis of H9C2 cells. The effects of HG on reduced expression of IGF-1R and increased apoptosis were blocked by silencing p53 with small interference RNA but not by non-targeting scrambled siRNA. Moreover, HG negatively regulated IGF-1R promoter activity as determined by ChIP analysis, which was dependent on p53 since siRNA-p53 attenuated the effects of HG on IGF-1R promoter activity. HG also increased the association of p53 with histone deacetylase 1 (HDAC1), and decreased the association of acetylated histone-4 with the IGF-1R promoter. Furthermore, HDAC inhibitor relieved the repression of IGF-1R following HG state. These results suggest that HG-induced repression of IGF-1R is mediated by the association of p53 with the IGF-1R promoter, and by the subsequent enhanced recruitment of chromatin-modifying proteins, such as HDAC1, to the IGF-1R promoter-p53 complex. In conclusion, our data demonstrate that HG decreases expression of IGF-1R and decreases the association of acetylated histone-4 with the IGF-1R promoter. These studies may help delineate the complex pathways regulating diabetic cardiomyopathy, and have implications for the development of novel therapeutic strategies to prevent diabetic cardiomyopathy by epigenetic regulation of IGF-1R.
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Affiliation(s)
- Xi-Yong Yu
- Medical Research Center, Guangdong General Hospital, Guangdong Provincial Cardiovascular Institute, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, P.R. China.
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Little MP. Do non-targeted effects increase or decrease low dose risk in relation to the linear-non-threshold (LNT) model? Mutat Res 2010; 687:17-27. [PMID: 20105434 PMCID: PMC3076714 DOI: 10.1016/j.mrfmmm.2010.01.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
In this paper we review the evidence for departure from linearity for malignant and non-malignant disease and in the light of this assess likely mechanisms, and in particular the potential role for non-targeted effects. Excess cancer risks observed in the Japanese atomic bomb survivors and in many medically and occupationally exposed groups exposed at low or moderate doses are generally statistically compatible. For most cancer sites the dose-response in these groups is compatible with linearity over the range observed. The available data on biological mechanisms do not provide general support for the idea of a low dose threshold or hormesis. This large body of evidence does not suggest, indeed is not statistically compatible with, any very large threshold in dose for cancer, or with possible hormetic effects, and there is little evidence of the sorts of non-linearity in response implied by non-DNA-targeted effects. There are also excess risks of various types of non-malignant disease in the Japanese atomic bomb survivors and in other groups. In particular, elevated risks of cardiovascular disease, respiratory disease and digestive disease are observed in the A-bomb data. In contrast with cancer, there is much less consistency in the patterns of risk between the various exposed groups; for example, radiation-associated respiratory and digestive diseases have not been seen in these other (non-A-bomb) groups. Cardiovascular risks have been seen in many exposed populations, particularly in medically exposed groups, but in contrast with cancer there is much less consistency in risk between studies: risks per unit dose in epidemiological studies vary over at least two orders of magnitude, possibly a result of confounding and effect modification by well known (but unobserved) risk factors. In the absence of a convincing mechanistic explanation of epidemiological evidence that is, at present, less than persuasive, a cause-and-effect interpretation of the reported statistical associations for cardiovascular disease is unreliable but cannot be excluded. Inflammatory processes are the most likely mechanism by which radiation could modify the atherosclerotic disease process. If there is to be modification by low doses of ionizing radiation of cardiovascular disease through this mechanism, a role for non-DNA-targeted effects cannot be excluded.
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Affiliation(s)
- M P Little
- Department of Epidemiology and Biostatistics, Imperial College School of Public Health, Faculty of Medicine, St Mary's Campus, Norfolk Place, London W2 1PG, UK.
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Smith TJ. Insulin-like growth factor-I regulation of immune function: a potential therapeutic target in autoimmune diseases? Pharmacol Rev 2010; 62:199-236. [PMID: 20392809 DOI: 10.1124/pr.109.002469] [Citation(s) in RCA: 185] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
This topically limited review explores the relationship between the immune system and insulin-like growth factors (IGF-I and IGF-II) and the proteins through which they act, including IGF-I receptor (IGF-IR) and the IGF-I binding proteins. The IGF/IGF-IR pathway plays important and diverse roles in tissue development and function. It regulates cell cycle progression, apoptosis, and the translation of proteins. Many of the consequences ascribed to IGF-IR activation result from its association with several accessory proteins that are either identical or closely related to those involved in insulin receptor signaling. Relatively recent awareness that IGF-I and IGF-IR regulate immune function has cast this pathway in an unexpected light; it may represent an important switch governing the quality and amplitude of immune responses. IGF-I/IGF-IR signaling may also participate in the pathogenesis of autoimmune diseases, although its relationship with these processes seems complex and relatively unexplored. On the one hand, IGF-I seems to protect experimental animals from developing insulin-deficient diabetes mellitus. In contrast, activating antibodies directed at IGF-IR have been detected in patients with Graves' disease, where the receptor is overexpressed by multiple cell types. The frequency of IGF-IR+ B and T cells is substantially increased in patients with that disease. Potential involvement of IGF-I and IGF-IR in the pathogenesis of autoimmune diseases suggests that this pathway might constitute an attractive therapeutic target. IGF-IR has been targeted in efforts directed toward drug development for cancer, employing both small-molecule and monoclonal antibody approaches. These have been generally well-tolerated. Recognizing the broader role of IGF-IR in regulating both normal and pathological immune responses may offer important opportunities for therapeutic intervention in several allied diseases that have proven particularly difficult to treat.
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Affiliation(s)
- Terry J Smith
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, 1000 Wall Street, Ann Arbor, MI 48105, USA.
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Tan NY, Li JM, Stocker R, Khachigian LM. Angiotensin II-inducible smooth muscle cell apoptosis involves the angiotensin II type 2 receptor, GATA-6 activation, and FasL-Fas engagement. Circ Res 2009; 105:422-30. [PMID: 19628789 DOI: 10.1161/circresaha.109.203323] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE Fas ligand (FasL)-mediated smooth muscle cell (SMC) apoptosis within the vulnerable plaque may lead to plaque instability and rupture, events that underlie myocardial infarction and stroke. OBJECTIVE The molecular mechanisms underlying FasL transcription and FasL-dependent SMC apoptosis were investigated in this study in vitro and in vivo. METHODS AND RESULTS We demonstrate that GATA-6, the predominant GATA family member expressed in SMCs, stimulates SMC apoptosis in an extracellular FasL-dependent manner. Both GATA-6 and FasL were inducibly and transiently expressed following balloon injury to rat carotid arteries. We identified two potential GATA binding in the FasL promoter and demonstrated using DNA binding and chromatin immunoprecipitation assays that GATA-6 regulates FasL through one ((-298)TTATCA(-303)) but not both these elements. Angiotensin II (Ang II) stimulated expression of both GATA-6 and FasL. Ang II increased SMC apoptosis in an Ang II type 2 receptor-, caspase 8-, and FasL-dependent fashion. GATA-6 activation was MEK-ERK1/2- and JNK-dependent, and GATA-6 small interfering RNA blocked Ang II-inducible FasL expression and SMC apoptosis. Administration of Ang II to rats increased FasL expression and apoptosis in carotid artery SMCs in an Ang II type 2 receptor- and GATA-6-dependent manner. CONCLUSIONS This study provides new insights into the transcriptional events underpinning FasL-dependent SMC apoptosis after exposure to Ang II.
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Affiliation(s)
- Nicole Y Tan
- Centre for Vascular Research, University of New South Wales, Sydney NSW 2052, Australia
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Ungewitter E, Scrable H. Antagonistic pleiotropy and p53. Mech Ageing Dev 2009; 130:10-7. [PMID: 18639575 PMCID: PMC2771578 DOI: 10.1016/j.mad.2008.06.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2008] [Revised: 04/29/2008] [Accepted: 06/12/2008] [Indexed: 12/30/2022]
Abstract
George Williams' antagonistic pleiotropy theory of aging proposes that cellular damage and organismal aging are caused by pleiotrophic genes, or genes with multiple phenotypic effects [Williams, G.C., 1957. Pleiotropy, natural selection, and the evolution of senescence. Evolution 11, 398-411]. According to this theory, genes that exhibit antagonistic pleiotropy increase the odds of successful reproduction early in life, but have deleterious effects later in life. The tumor suppressor p53 confers protection against cancer (and death) by interrupting the abnormal proliferation of cells. When control of proliferation is applied to normal stem cells, however, it can impair tissue homeostasis and accelerate aging. We use data from recently developed models of accelerated aging in mice to determine if the deleterious effects of p53 on aging reflect antagonistic pleiotropy of the p53 gene or are attributable to genes that can modify p53 activity but are evolving independently.
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Allard D, Figg N, Bennett MR, Littlewood TD. Akt regulates the survival of vascular smooth muscle cells via inhibition of FoxO3a and GSK3. J Biol Chem 2008; 283:19739-47. [PMID: 18458087 DOI: 10.1074/jbc.m710098200] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Apoptosis of vascular smooth muscle cells (VSMCs) may lead to atherosclerotic plaque instability and rupture, resulting in myocardial infarction, stroke, and sudden death. However, the molecular mechanisms mediating survival of VSMCs in atherosclerotic plaques remain unknown. Although plaque VSMCs exhibit increased susceptibility to apoptosis and reduced expression of the IGF1 receptor (IGF1R) when compared with normal VSMCs, a causative effect has not been established. Here we show that increased expression of the IGF1R can rescue plaque VSMCs from oxidative stress-induced apoptosis, demonstrating that IGF-1 signaling is a critical regulator of VSMC survival. Akt mediates the majority of the IGF1R survival signaling, and ectopic activation of Akt was sufficient to protect VSMCs in vitro. Both IGF1R and phospho-Akt expression were reduced in human plaque (intimal) VSMCs when compared with medial VSMCs, suggesting that Akt mediates survival signaling in atherosclerosis. Importantly, downstream targets of Akt were identified that mediate its protective effect as inhibition of FoxO3a or GSK3 by Akt-dependent phosphorylation protected VSMCs in vitro. We conclude that Akt and its downstream targets FoxO3a and GSK3 regulate a survival pathway in VSMCs and that their deregulation due to a reduction of IGF1R signaling may promote apoptosis in atherosclerosis.
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Affiliation(s)
- David Allard
- Division of Cardiovascular Medicine, University of Cambridge, Box 110, Addenbrooke's Hospital, Cambridge CB2 2QQ, United Kingdom
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Kavurma MM, Schoppet M, Bobryshev YV, Khachigian LM, Bennett MR. TRAIL stimulates proliferation of vascular smooth muscle cells via activation of NF-kappaB and induction of insulin-like growth factor-1 receptor. J Biol Chem 2008; 283:7754-62. [PMID: 18178561 DOI: 10.1074/jbc.m706927200] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
TRAIL/Apo2L (tumor necrosis factor-related apoptosis-inducing ligand) is a multifunctional protein regulating homeostasis of the immune system, infection, autoimmune diseases, and apoptosis. However, its function in normal, nontransformed tissues is not clear. Here we show that TRAIL increases vascular smooth muscle cell (VSMC) proliferation in vitro, effects that can be blocked with neutralizing antibodies to TRAIL receptors DR4 and DcR1. In aortocoronary saphenous vein bypass grafts in vivo, TRAIL co-localizes with VSMC, proliferating cell nuclear antigen, and insulin-like growth factor type 1 receptor (IGF1R) expression but not active caspase-3. TRAIL is required for serum-inducible IGF1R expression, and antisense IGF1R inhibits TRAIL-induced VSMC proliferation. At 1 ng/ml, TRAIL stimulates IGF1R mRNA expression greater than insulin-like growth factor-1 and also activates the IGF1R promoter 7-fold. TRAIL-inducible IGF1R expression requires NF-kappaB activation. Consistent with this, ammonium pyrrolidine dithiocarbamate, a pharmacological inhibitor of NF-kappaB, blocks TRAIL-induced IGF1R expression, and p65 overexpression increases IGF1R protein levels. In addition, NF-kappaB binds a novel TRAIL-responsive element on the IGF1R promoter. Our findings suggest that the biological functions of TRAIL in VSMC extend beyond its role in promoting apoptosis. Thus, TRAIL may play an important role in atherosclerosis by regulating IGF1R expression in VSMC in an NF-kappaB-dependent manner.
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Affiliation(s)
- Mary M Kavurma
- Division of Cardiovascular Medicine, University of Cambridge, Box 110, Addenbrooke's Hospital, Cambridge CB2 2QQ, United Kingdom
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