1
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Yang Z, Zhang R, Liu J, Tian S, Zhang H, Zeng L, Zhang Y, Gao L, Wang M, Shan W, Liu J. The mechanism of RGS5 regulating gastric cancer mismatch repair protein. Mol Carcinog 2024; 63:1750-1767. [PMID: 38860604 DOI: 10.1002/mc.23770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 05/11/2024] [Accepted: 05/24/2024] [Indexed: 06/12/2024]
Abstract
The incidence and mortality rates of gastric cancer (GC) remain alarmingly high worldwide, imposing a substantial healthcare burden. In this study, we utilized data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. A 4-gene prognostic model was developed to predict patient prognosis, and its accuracy was validated across multiple datasets. Patients with a low-risk score exhibited improved prognosis, elevated tumor mutation burden, heightened sensitivity to both immunotherapy and conventional chemotherapy. Notably, our investigation revealed that the key gene RGS5 positively modulates the expression of mismatch repair proteins via c-Myc. Furthermore, co-immunoprecipitation (COIP) assays demonstrated the interaction between RGS5 and c-Myc. Additionally, we confirmed that RGS5 regulates c-Myc through the ubiquitin-proteasome pathway. Moreover, RGS5 was identified as a positive regulator of PD-L1 expression and exhibited a negative correlation with the majority of immune cells. These findings underscore the potential of RGS5 as a novel biomarker and therapeutic target in the context of GC.
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Affiliation(s)
- Zhenwei Yang
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei Province, China
- Key Laboratory of Intestinal and Colorectal Diseases, Hubei Clinical Center, Wuhan, China
| | - Ranran Zhang
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei Province, China
- Key Laboratory of Intestinal and Colorectal Diseases, Hubei Clinical Center, Wuhan, China
| | - Jialong Liu
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei Province, China
- Key Laboratory of Intestinal and Colorectal Diseases, Hubei Clinical Center, Wuhan, China
| | - Sufang Tian
- Department of Pathology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Hailin Zhang
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei Province, China
- Key Laboratory of Intestinal and Colorectal Diseases, Hubei Clinical Center, Wuhan, China
| | - Lingxiu Zeng
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei Province, China
- Key Laboratory of Intestinal and Colorectal Diseases, Hubei Clinical Center, Wuhan, China
| | - Yangyang Zhang
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei Province, China
- Key Laboratory of Intestinal and Colorectal Diseases, Hubei Clinical Center, Wuhan, China
| | - Liping Gao
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei Province, China
- Key Laboratory of Intestinal and Colorectal Diseases, Hubei Clinical Center, Wuhan, China
| | - Meng Wang
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei Province, China
- Key Laboratory of Intestinal and Colorectal Diseases, Hubei Clinical Center, Wuhan, China
| | - Wenqing Shan
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei Province, China
- Key Laboratory of Intestinal and Colorectal Diseases, Hubei Clinical Center, Wuhan, China
| | - Jing Liu
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei Province, China
- Key Laboratory of Intestinal and Colorectal Diseases, Hubei Clinical Center, Wuhan, China
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Lymperopoulos A, Suster MS, Borges JI. Cardiovascular GPCR regulation by regulator of G protein signaling proteins. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2022; 193:145-166. [PMID: 36357075 DOI: 10.1016/bs.pmbts.2022.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
G protein-coupled receptors (GPCRs) play pivotal roles in regulation of cardiovascular homeostasis across all vertebrate species, including humans. In terms of normal cellular function, termination of GPCR signaling via the heterotrimeric G proteins is equally (if not more) important to its stimulation. The Regulator of G protein Signaling (RGS) protein superfamily are indispensable for GPCR signaling cessation at the cell membrane, and thus, for cellular control of GPCR signaling and function. Perturbations in both activation and termination of G protein signaling underlie many examples of cardiovascular dysfunction and heart disease pathogenesis. Despite the plethora of over 30 members comprising the mammalian RGS protein superfamily, each member interacts with a specific set of second messenger pathways and GPCR types/subtypes in a tissue/cell type-specific manner. An increasing number of studies over the past two decades have provided compelling evidence for the involvement of various RGS proteins in physiological regulation of cardiovascular GPCRs and, consequently, also in the pathophysiology of several cardiovascular ailments. This chapter summarizes the current understanding of the functional roles of RGS proteins as they pertain to cardiovascular, i.e., heart, blood vessel, and platelet GPCR function, with a particular focus on their implications for chronic heart failure pathophysiology and therapy.
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Affiliation(s)
- Anastasios Lymperopoulos
- Laboratory for the Study of Neurohormonal Control of the Circulation, Department of Pharmaceutical Sciences, Nova Southeastern University College of Pharmacy, Fort Lauderdale, FL, United States.
| | - Malka S Suster
- Laboratory for the Study of Neurohormonal Control of the Circulation, Department of Pharmaceutical Sciences, Nova Southeastern University College of Pharmacy, Fort Lauderdale, FL, United States
| | - Jordana I Borges
- Laboratory for the Study of Neurohormonal Control of the Circulation, Department of Pharmaceutical Sciences, Nova Southeastern University College of Pharmacy, Fort Lauderdale, FL, United States
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A regulator of G protein signaling 5 marked subpopulation of vascular smooth muscle cells is lost during vascular disease. PLoS One 2022; 17:e0265132. [PMID: 35320283 PMCID: PMC8942229 DOI: 10.1371/journal.pone.0265132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 02/23/2022] [Indexed: 11/19/2022] Open
Abstract
Vascular smooth muscle cell (VSMC) subpopulations relevant to vascular disease and injury repair have been depicted in healthy vessels and atherosclerosis profiles. However, whether VSMC subpopulation associated with vascular homeostasis exists in the healthy artery and how are their nature and fate in vascular remodeling remains elusive. Here, using single-cell RNA-sequencing (scRNA-seq) to detect VSMC functional heterogeneity in an unbiased manner, we showed that VSMC subpopulations in healthy artery presented transcriptome diversity and that there was significant heterogeneity in differentiation state and development within each subpopulation. Notably, we detected an independent subpopulation of VSMCs that highly expressed regulator of G protein signaling 5 (RGS5), upregulated the genes associated with inhibition of cell proliferation and construction of cytoskeleton compared with the general subpopulation, and mainly enriched in descending aorta. Additionally, the proportion of RGS5high VSMCs was markedly decreased or almost disappeared in the vascular tissues of neointimal formation, abdominal aortic aneurysm and atherosclerosis. Specific spatiotemporal characterization of RGS5high VSMC subpopulation suggested that this subpopulation was implicated in vascular homeostasis. Together, our analyses identify homeostasis-relevant transcriptional signatures of VSMC subpopulations in healthy artery, which may explain the regional vascular resistance to atherosclerosis at some extent.
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RGS5-TGFβ-Smad2/3 axis switches pro- to anti-apoptotic signaling in tumor-residing pericytes, assisting tumor growth. Cell Death Differ 2021; 28:3052-3076. [PMID: 34012071 PMCID: PMC8564526 DOI: 10.1038/s41418-021-00801-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 04/29/2021] [Accepted: 05/03/2021] [Indexed: 02/04/2023] Open
Abstract
Regulator-of-G-protein-signaling-5 (RGS5), a pro-apoptotic/anti-proliferative protein, is a signature molecule of tumor-associated pericytes, highly expressed in several cancers, and is associated with tumor growth and poor prognosis. Surprisingly, despite the negative influence of intrinsic RGS5 expression on pericyte survival, RGS5highpericytes accumulate in progressively growing tumors. However, responsible factor(s) and altered-pathway(s) are yet to report. RGS5 binds with Gαi/q and promotes pericyte apoptosis in vitro, subsequently blocking GPCR-downstream PI3K-AKT signaling leading to Bcl2 downregulation and promotion of PUMA-p53-Bax-mediated mitochondrial damage. However, within tumor microenvironment (TME), TGFβ appeared to limit the cytocidal action of RGS5 in tumor-residing RGS5highpericytes. We observed that in the presence of high RGS5 concentrations, TGFβ-TGFβR interactions in the tumor-associated pericytes lead to the promotion of pSmad2-RGS5 binding and nuclear trafficking of RGS5, which coordinately suppressed RGS5-Gαi/q and pSmad2/3-Smad4 pairing. The RGS5-TGFβ-pSmad2 axis thus mitigates both RGS5- and TGFβ-dependent cellular apoptosis, resulting in sustained pericyte survival/expansion within the TME by rescuing PI3K-AKT signaling and preventing mitochondrial damage and caspase activation. This study reports a novel mechanism by which TGFβ fortifies and promotes survival of tumor pericytes by switching pro- to anti-apoptotic RGS5 signaling in TME. Understanding this altered RGS5 signaling might prove beneficial in designing future cancer therapy.
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Amato CM, Yao HHC. Developmental and sexual dimorphic atlas of the prenatal mouse external genitalia at the single-cell level. Proc Natl Acad Sci U S A 2021; 118:e2103856118. [PMID: 34155146 PMCID: PMC8237666 DOI: 10.1073/pnas.2103856118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Birth defects of the external genitalia are among the most common in the world. Proper formation of the external genitalia requires a highly orchestrated process that involves special cell populations and sexually dimorphic hormone signaling. It is clear what the end result of the sexually dimorphic development is (a penis in the male versus clitoris in the female); however, the cell populations involved in the process remain poorly defined. Here, we used single-cell messenger RNA sequencing in mouse embryos to uncover the dynamic changes in cell populations in the external genitalia during the critical morphogenetic window. We found that overall, male and female external genitalia are largely composed of the same core cellular components. At the bipotential stage of development (embryonic day or E14.5), few differences in cell populational composition exist between male and female. Although similar in cell population composition, genetic differences in key sexual differentiation developmental pathways arise between males and females by the early (E16.5) and late (E18.5) differentiation stages. These differences include discrete cell populations with distinct responsiveness to androgen and estrogen. By late sexual differentiation (E18.5), unique cell populations in both male and female genitalia become apparent and are enriched with androgen- and estrogen-responsive genes, respectively. These data provide insights into the morphogenesis of the external genitalia that could be used to understand diseases associated with defects in the external genitalia.
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Affiliation(s)
- Ciro Maurizio Amato
- Reproductive Developmental Biology Group, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709
| | - Humphrey Hung-Chang Yao
- Reproductive Developmental Biology Group, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709
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Johnson GL, Masias EJ, Lehoczky JA. Cellular Heterogeneity and Lineage Restriction during Mouse Digit Tip Regeneration at Single-Cell Resolution. Dev Cell 2020; 52:525-540.e5. [PMID: 32097654 PMCID: PMC7186907 DOI: 10.1016/j.devcel.2020.01.026] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 01/22/2020] [Accepted: 01/23/2020] [Indexed: 12/27/2022]
Abstract
Innate regeneration following digit tip amputation is one of the few examples of epimorphic regeneration in mammals. Digit tip regeneration is mediated by the blastema, the same structure invoked during limb regeneration in some lower vertebrates. By genetic lineage analyses, the digit tip blastema has been defined as a population of heterogeneous, lineage-restricted progenitor cells. These previous studies, however, do not comprehensively evaluate blastema heterogeneity or address lineage restriction of closely related cell types. In this report, we present single-cell RNA sequencing of over 38,000 cells from mouse digit tip blastemas and unamputated control digit tips and generate an atlas of the cell types participating in digit tip regeneration. We computationally define differentiation trajectories of vascular, monocytic, and fibroblastic lineages over regeneration, and while our data confirm broad lineage restriction of progenitors, our analysis reveals 67 genes enriched in blastema fibroblasts including a novel regeneration-specific gene, Mest.
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Affiliation(s)
- Gemma L Johnson
- Department of Orthopedic Surgery, Brigham and Women's Hospital, Boston, MA 02115, USA; Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Erick J Masias
- Department of Orthopedic Surgery, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Jessica A Lehoczky
- Department of Orthopedic Surgery, Brigham and Women's Hospital, Boston, MA 02115, USA.
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7
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Human cytomegalovirus promoting endothelial cell proliferation by targeting regulator of G-protein signaling 5 hypermethylation and downregulation. Sci Rep 2020; 10:2252. [PMID: 32041970 PMCID: PMC7010708 DOI: 10.1038/s41598-020-58680-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 01/15/2020] [Indexed: 01/21/2023] Open
Abstract
Interactions between human cytomegalovirus (HCMV) infection and environmental factors can increase susceptibility to essential hypertension (EH). Although endothelial dysfunction is the initial factor of EH, the epigenetic mechanisms through which HCMV infection induces endothelial cell dysfunction are poorly understood. Here, we evaluated whether HCMV regulated endothelial cell function and assessed the underlying mechanisms. Microarray analysis in human umbilical vein endothelial cells (HUVECs) treated with HCMV AD169 strain in the presence of hyperglycemia and hyperlipidemia revealed differential expression of genes involved in hypertension. Further analyses validated that the regulator of G-protein signaling 5 (RGS5) gene was downregulated in infected HUVECs and showed that HCMV infection promoted HUVEC proliferation, whereas hyperglycemia and hyperlipidemia inhibited HUVEC proliferation. Additionally, treatment with decitabine (DAC) and RGS5 reversed the effects of HCMV infection on HUVEC proliferation, but not triggered by hyperglycemia and hyperlipidemia. In summary, upregulation of RGS5 may be a promising treatment for preventing HCMV-induced hypertension.
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Squires KE, Montañez-Miranda C, Pandya RR, Torres MP, Hepler JR. Genetic Analysis of Rare Human Variants of Regulators of G Protein Signaling Proteins and Their Role in Human Physiology and Disease. Pharmacol Rev 2018; 70:446-474. [PMID: 29871944 DOI: 10.1124/pr.117.015354] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Regulators of G protein signaling (RGS) proteins modulate the physiologic actions of many neurotransmitters, hormones, and other signaling molecules. Human RGS proteins comprise a family of 20 canonical proteins that bind directly to G protein-coupled receptors/G protein complexes to limit the lifetime of their signaling events, which regulate all aspects of cell and organ physiology. Genetic variations account for diverse human traits and individual predispositions to disease. RGS proteins contribute to many complex polygenic human traits and pathologies such as hypertension, atherosclerosis, schizophrenia, depression, addiction, cancers, and many others. Recent analysis indicates that most human diseases are due to extremely rare genetic variants. In this study, we summarize physiologic roles for RGS proteins and links to human diseases/traits and report rare variants found within each human RGS protein exome sequence derived from global population studies. Each RGS sequence is analyzed using recently described bioinformatics and proteomic tools for measures of missense tolerance ratio paired with combined annotation-dependent depletion scores, and protein post-translational modification (PTM) alignment cluster analysis. We highlight selected variants within the well-studied RGS domain that likely disrupt RGS protein functions and provide comprehensive variant and PTM data for each RGS protein for future study. We propose that rare variants in functionally sensitive regions of RGS proteins confer profound change-of-function phenotypes that may contribute, in newly appreciated ways, to complex human diseases and/or traits. This information provides investigators with a valuable database to explore variation in RGS protein function, and for targeting RGS proteins as future therapeutic targets.
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Affiliation(s)
- Katherine E Squires
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia (K.E.S., C.M.-M., J.R.H.); and School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia (R.R.P., M.P.T.)
| | - Carolina Montañez-Miranda
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia (K.E.S., C.M.-M., J.R.H.); and School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia (R.R.P., M.P.T.)
| | - Rushika R Pandya
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia (K.E.S., C.M.-M., J.R.H.); and School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia (R.R.P., M.P.T.)
| | - Matthew P Torres
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia (K.E.S., C.M.-M., J.R.H.); and School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia (R.R.P., M.P.T.)
| | - John R Hepler
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia (K.E.S., C.M.-M., J.R.H.); and School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia (R.R.P., M.P.T.)
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Perschbacher KJ, Deng G, Fisher RA, Gibson-Corley KN, Santillan MK, Grobe JL. Regulators of G protein signaling in cardiovascular function during pregnancy. Physiol Genomics 2018; 50:590-604. [PMID: 29702036 PMCID: PMC6139632 DOI: 10.1152/physiolgenomics.00037.2018] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
G protein-coupled receptor signaling mechanisms are implicated in many aspects of cardiovascular control, and dysfunction of such signaling mechanisms is commonly associated with disease states. Investigators have identified a large number of regulator of G protein signaling (RGS) proteins that variously contribute to the modulation of intracellular second-messenger signaling kinetics. These many RGS proteins each interact with a specific set of second-messenger cascades and receptor types and exhibit tissue-specific expression patterns. Increasing evidence supports the contribution of RGS proteins, or their loss, in the pathogenesis of cardiovascular dysfunctions. This review summarizes the current understanding of the functional contributions of RGS proteins, particularly within the B/R4 family, in cardiovascular disorders of pregnancy including gestational hypertension, uterine artery dysfunction, and preeclampsia.
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Affiliation(s)
| | - Guorui Deng
- Department of Pharmacology, University of Iowa , Iowa City, Iowa
| | - Rory A Fisher
- Department of Pharmacology, University of Iowa , Iowa City, Iowa
| | - Katherine N Gibson-Corley
- Department of Pathology, University of Iowa , Iowa City, Iowa
- UIHC Center for Hypertension Research, University of Iowa , Iowa City, Iowa
| | - Mark K Santillan
- Department of Obstetrics & Gynecology, University of Iowa , Iowa City, Iowa
- UIHC Center for Hypertension Research, University of Iowa , Iowa City, Iowa
- Abboud Cardiovascular Research Center, University of Iowa , Iowa City, Iowa
| | - Justin L Grobe
- Department of Pharmacology, University of Iowa , Iowa City, Iowa
- UIHC Center for Hypertension Research, University of Iowa , Iowa City, Iowa
- Abboud Cardiovascular Research Center, University of Iowa , Iowa City, Iowa
- Fraternal Order of Eagles' Diabetes Research Center, University of Iowa , Iowa City, Iowa
- Obesity Education & Research Initiative, University of Iowa , Iowa City, Iowa
- Iowa Neuroscience Institute, University of Iowa , Iowa City, Iowa
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Ding HS, Huang Y, Chen Z, Tang YH, Wang DD, Fan D, Huang CX. Regulator of G-protein signalling 5 deficiency impairs ventricular remodelling after myocardial infarction by promoting NF-κB and MAPK signalling in mice. Biochem Biophys Res Commun 2018. [DOI: 10.1016/j.bbrc.2018.03.082] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Hong K, Li M, Nourian Z, Meininger GA, Hill MA. Angiotensin II Type 1 Receptor Mechanoactivation Involves RGS5 (Regulator of G Protein Signaling 5) in Skeletal Muscle Arteries: Impaired Trafficking of RGS5 in Hypertension. Hypertension 2017; 70:1264-1272. [PMID: 29061726 DOI: 10.1161/hypertensionaha.117.09757] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 06/11/2017] [Accepted: 09/20/2017] [Indexed: 01/07/2023]
Abstract
Studies suggest that arteriolar pressure-induced vasoconstriction can be initiated by GPCRs (G protein-coupled receptors), including the AT1R (angiotensin II type 1 receptor). This raises the question, are such mechanisms regulated by negative feedback? The present studies examined whether RGS (regulators of G protein signaling) proteins in vascular smooth muscle cells are colocalized with the AT1R when activated by mechanical stress or angiotensin II and whether this modulates AT1R-mediated vasoconstriction. To determine whether activation of the AT1R recruits RGS5, an in situ proximity ligation assay was performed in primary cultures of cremaster muscle arteriolar vascular smooth muscle cells treated with angiotensin II or hypotonic solution in the absence or presence of candesartan (an AT1R blocker). Proximity ligation assay results revealed a concentration-dependent increase in trafficking/translocation of RGS5 toward the activated AT1R, which was attenuated by candesartan. In intact arterioles, knockdown of RGS5 enhanced constriction to angiotensin II and augmented myogenic responses to increased intraluminal pressure. Myogenic constriction was attenuated to a higher degree by candesartan in RGS5 siRNA-transfected arterioles, consistent with RGS5 contributing to downregulation of AT1R-mediated signaling. Further, translocation of RGS5 was impaired in vascular smooth muscle cells of spontaneously hypertensive rats. This is consistent with dysregulated (RGS5-mediated) AT1R signaling that could contribute to excessive vasoconstriction in hypertension. In intact vessels, candesartan reduced myogenic vasoconstriction to a greater extent in spontaneously hypertensive rats compared with controls. Collectively, these findings suggest that AT1R activation results in translocation of RGS5 toward the plasma membrane, limiting AT1R-mediated vasoconstriction through its role in Gq/11 protein-dependent signaling.
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Affiliation(s)
- Kwangseok Hong
- From the Department of Medical Pharmacology and Physiology (K.H., M.L., G.A.M., M.A.H.) and Dalton Cardiovascular Research Center (K.H., Z.N., G.A.M., M.A.H.), University of Missouri, Columbia; and Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville (K.H.)
| | - Min Li
- From the Department of Medical Pharmacology and Physiology (K.H., M.L., G.A.M., M.A.H.) and Dalton Cardiovascular Research Center (K.H., Z.N., G.A.M., M.A.H.), University of Missouri, Columbia; and Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville (K.H.)
| | - Zahra Nourian
- From the Department of Medical Pharmacology and Physiology (K.H., M.L., G.A.M., M.A.H.) and Dalton Cardiovascular Research Center (K.H., Z.N., G.A.M., M.A.H.), University of Missouri, Columbia; and Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville (K.H.)
| | - Gerald A Meininger
- From the Department of Medical Pharmacology and Physiology (K.H., M.L., G.A.M., M.A.H.) and Dalton Cardiovascular Research Center (K.H., Z.N., G.A.M., M.A.H.), University of Missouri, Columbia; and Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville (K.H.)
| | - Michael A Hill
- From the Department of Medical Pharmacology and Physiology (K.H., M.L., G.A.M., M.A.H.) and Dalton Cardiovascular Research Center (K.H., Z.N., G.A.M., M.A.H.), University of Missouri, Columbia; and Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville (K.H.).
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12
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Liu C, Hu Q, Jing J, Zhang Y, Jin J, Zhang L, Mu L, Liu Y, Sun B, Zhang T, Kong Q, Wang G, Wang D, Zhang Y, Liu X, Zhao W, Wang J, Feng T, Li H. Regulator of G protein signaling 5 (RGS5) inhibits sonic hedgehog function in mouse cortical neurons. Mol Cell Neurosci 2017; 83:65-73. [PMID: 28684360 DOI: 10.1016/j.mcn.2017.06.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Revised: 02/21/2017] [Accepted: 06/20/2017] [Indexed: 12/12/2022] Open
Abstract
Regulator of G protein signaling 5 (RGS5) acts as a GTPase-activating protein (GAP) for the Gαi subunit and negatively regulates G protein-coupled receptor signaling. However, its presence and function in postmitotic differentiated primary neurons remains largely uncharacterized. During neural development, sonic hedgehog (Shh) signaling is involved in cell signaling pathways via Gαi activity. In particular, Shh signaling is essential for embryonic neural tube patterning, which has been implicated in neuronal polarization involving neurite outgrowth. Here, we examined whether RGS5 regulates Shh signaling in neurons. RGS5 transcripts were found to be expressed in cortical neurons and their expression gradually declined in a time-dependent manner in culture system. When an adenovirus expressing RGS5 was introduced into an in vitro cell culture model of cortical neurons, RGS5 overexpression significantly reduced neurite outgrowth and FM4-64 uptake, while cAMP-PKA signaling was also affected. These findings suggest that RGS5 inhibits Shh function during neurite outgrowth and the presynaptic terminals of primary cortical neurons mature via modulation of cAMP.
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Affiliation(s)
- Chuanliang Liu
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China; Vocational College Daxing'an Mountains, Jiagedaqi District, Heilongjiang 165000, China
| | - Qiongqiong Hu
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Jia Jing
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Yun Zhang
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Jing Jin
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Liulei Zhang
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Lili Mu
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Yumei Liu
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Bo Sun
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Tongshuai Zhang
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Qingfei Kong
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Guangyou Wang
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Dandan Wang
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Yao Zhang
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Xijun Liu
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Wei Zhao
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China
| | - Jinghua Wang
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China.
| | - Tao Feng
- Department of Neurology, The Nangang Branch of Heilongjiang Provincial Hospital, Harbin, Heilongjiang 150001, China.
| | - Hulun Li
- Department of Neurobiology, Harbin Medical University, Heilongjiang Provincial Key Laboratory of Neurobiology, Harbin, Heilongjiang 150086, China; Key Laboratories of Education Ministry for Myocardial Ischemia Mechanism and Treatment, Harbin, Heilongjiang 150086, China
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13
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Wang Z, Huang H, He W, Kong B, Hu H, Fan Y, Liao J, Wang L, Mei Y, Liu W, Xiong X, Peng J, Xiao Y, Huang D, Quan D, Li Q, Xiong L, Zhong P, Wang G. Regulator of G-protein signaling 5 protects cardiomyocytes against apoptosis during in vitro cardiac ischemia-reperfusion in mice by inhibiting both JNK1/2 and P38 signaling pathways. Biochem Biophys Res Commun 2016; 473:551-7. [DOI: 10.1016/j.bbrc.2016.03.114] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 03/23/2016] [Indexed: 01/23/2023]
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Daniel JM, Prock A, Dutzmann J, Sonnenschein K, Thum T, Bauersachs J, Sedding DG. Regulator of G-Protein Signaling 5 Prevents Smooth Muscle Cell Proliferation and Attenuates Neointima Formation. Arterioscler Thromb Vasc Biol 2015; 36:317-27. [PMID: 26663397 DOI: 10.1161/atvbaha.115.305974] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 11/24/2015] [Indexed: 12/20/2022]
Abstract
OBJECTIVE Regulator of G-protein signaling 5 (RGS5) is abundantly expressed in vascular smooth muscle cells (SMCs) and inhibits G-protein signaling by enhancing the guanosine triphosphate-hydrolyzing activity of Gα-subunits. In the present study, we investigated the effects of RGS5 on vascular SMC function in vitro and neointima formation after wire-induced injury in mice and determined the underlying mechanisms. APPROACH AND RESULTS We found a robust expression of RGS5 in native arteries of C57BL/6 mice and a highly significant downregulation within neointimal lesions 10 and 21 days after vascular injury as assessed by quantitative polymerase chain reaction, immunoblotting, and immunohistochemistry. In vitro, RGS5 was found significantly downregulated after mitogenic stimulation of human coronary artery SMCs. To restore RGS5 levels, SMCs were transduced with adenoviral vectors encoding wild-type RGS5 or a nondegradable mutant. RGS5-WT and, even more prominently, the C2A-RGS5 mutant prevented SMC proliferation and migration. In contrast, the siRNA-mediated knockdown of RGS5 significantly augmented SMC proliferation. Following overexpression of RGS5, fluorescence-activated cell sorting analysis of propidium iodide-stained cells indicated cell cycle arrest in G0/G1 phase. Mechanistically, inhibition of the phosphorylation of the extracellular signal-regulated kinase 1/2 and mitogen-activated protein kinase downstream signaling was shown to be responsible for the anti-proliferative effect of RGS5. Following wire-induced injury of the femoral artery in C57BL/6 mice, adenoviral-mediated overexpression of RGS5-WT or C2A-RGS5 significantly reduced SMC proliferation and neointima formation in vivo. CONCLUSIONS Downregulation of RGS5 is an important prerequisite for SMC proliferation in vitro and in vivo. Therefore, reconstitution of RGS5 levels represents a promising therapeutic option to prevent vascular remodeling processes.
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Affiliation(s)
- Jan-Marcus Daniel
- From the Department of Cardiology and Angiology (J.-M.D., J.D., K.S., J.B., D.G.S.), REBIRTH Excellence Cluster (J.-M.D., T.T., J.B., D.G.S.), and Institute of Molecular and Translational Therapeutic Strategies (IMTTS) (K.S., T.T.), Hannover Medical School, Hannover, Germany; Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany (A.P.); and National Heart and Lung Institute, Imperial College London, London, UK (T.T.)
| | - André Prock
- From the Department of Cardiology and Angiology (J.-M.D., J.D., K.S., J.B., D.G.S.), REBIRTH Excellence Cluster (J.-M.D., T.T., J.B., D.G.S.), and Institute of Molecular and Translational Therapeutic Strategies (IMTTS) (K.S., T.T.), Hannover Medical School, Hannover, Germany; Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany (A.P.); and National Heart and Lung Institute, Imperial College London, London, UK (T.T.)
| | - Jochen Dutzmann
- From the Department of Cardiology and Angiology (J.-M.D., J.D., K.S., J.B., D.G.S.), REBIRTH Excellence Cluster (J.-M.D., T.T., J.B., D.G.S.), and Institute of Molecular and Translational Therapeutic Strategies (IMTTS) (K.S., T.T.), Hannover Medical School, Hannover, Germany; Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany (A.P.); and National Heart and Lung Institute, Imperial College London, London, UK (T.T.)
| | - Kristina Sonnenschein
- From the Department of Cardiology and Angiology (J.-M.D., J.D., K.S., J.B., D.G.S.), REBIRTH Excellence Cluster (J.-M.D., T.T., J.B., D.G.S.), and Institute of Molecular and Translational Therapeutic Strategies (IMTTS) (K.S., T.T.), Hannover Medical School, Hannover, Germany; Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany (A.P.); and National Heart and Lung Institute, Imperial College London, London, UK (T.T.)
| | - Thomas Thum
- From the Department of Cardiology and Angiology (J.-M.D., J.D., K.S., J.B., D.G.S.), REBIRTH Excellence Cluster (J.-M.D., T.T., J.B., D.G.S.), and Institute of Molecular and Translational Therapeutic Strategies (IMTTS) (K.S., T.T.), Hannover Medical School, Hannover, Germany; Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany (A.P.); and National Heart and Lung Institute, Imperial College London, London, UK (T.T.)
| | - Johann Bauersachs
- From the Department of Cardiology and Angiology (J.-M.D., J.D., K.S., J.B., D.G.S.), REBIRTH Excellence Cluster (J.-M.D., T.T., J.B., D.G.S.), and Institute of Molecular and Translational Therapeutic Strategies (IMTTS) (K.S., T.T.), Hannover Medical School, Hannover, Germany; Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany (A.P.); and National Heart and Lung Institute, Imperial College London, London, UK (T.T.)
| | - Daniel G Sedding
- From the Department of Cardiology and Angiology (J.-M.D., J.D., K.S., J.B., D.G.S.), REBIRTH Excellence Cluster (J.-M.D., T.T., J.B., D.G.S.), and Institute of Molecular and Translational Therapeutic Strategies (IMTTS) (K.S., T.T.), Hannover Medical School, Hannover, Germany; Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany (A.P.); and National Heart and Lung Institute, Imperial College London, London, UK (T.T.).
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15
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Shen J, Shrestha S, Yen YH, Scott MA, Soo C, Ting K, Peault B, Dry SM, James AW. The pericyte antigen RGS5 in perivascular soft tissue tumors. Hum Pathol 2015; 47:121-31. [PMID: 26558691 DOI: 10.1016/j.humpath.2015.09.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 09/07/2015] [Accepted: 09/10/2015] [Indexed: 12/12/2022]
Abstract
Perivascular soft tissue tumors are relatively uncommon neoplasms of unclear lineage of differentiation, although most are presumed to originate from or differentiate to pericytes or a modified perivascular cell. Among these, glomus tumor, myopericytoma, and angioleiomyoma share a spectrum of histologic findings and a perivascular growth pattern. In contrast, solitary fibrous tumor was once hypothesized to have pericytic differentiation--although little bona fide evidence of pericytic differentiation exists. Likewise the perivascular epithelioid cell tumor (PEComa) family shares a perivascular growth pattern, but with distinctive dual myoid-melanocytic differentiation. RGS5, regulator of G-protein signaling 5, is a novel pericyte antigen with increasing use in animal models. Here, we describe the immunohistochemical expression patterns of RGS5 across perivascular soft tissue tumors, including glomus tumor (n = 6), malignant glomus tumor (n = 4), myopericytoma (n = 3), angioleiomyoma (n = 9), myofibroma (n = 4), solitary fibrous tumor (n = 10), and PEComa (n = 19). Immunohistochemical staining and semi-quantification was performed, and compared to αSMA (smooth muscle actin) expression. Results showed that glomus tumor (including malignant glomus tumor), myopericytoma, and angioleiomyoma shared a similar diffuse immunoreactivity for RGS5 and αSMA across all tumors examined. In contrast, myofibroma, solitary fibrous tumor and PEComa showed predominantly focal to absent RGS5 immunoreactivity. These findings further support a common pericytic lineage of differentiation in glomus tumors, myopericytoma and angioleiomyoma. The pericyte marker RGS5 may be of future clinical utility for the evaluation of pericytic differentiation in soft tissue tumors.
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Affiliation(s)
- Jia Shen
- School of Dentistry, University of California, Los Angeles, CA, 90095
| | - Swati Shrestha
- School of Dentistry, University of California, Los Angeles, CA, 90095; Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095
| | - Yu-Hsin Yen
- School of Dentistry, University of California, Los Angeles, CA, 90095; Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095
| | | | - Chia Soo
- Orthopedic Hospital Research Center, University of California, Los Angeles, CA, 90095; Department of Surgery, University of California, Los Angeles, Los Angeles, CA, 90095
| | - Kang Ting
- School of Dentistry, University of California, Los Angeles, CA, 90095
| | - Bruno Peault
- Orthopedic Hospital Research Center, University of California, Los Angeles, CA, 90095; Center for Regenerative Medicine, University of Edinburgh, Edinburgh, UK, EH16 4UU
| | - Sarah M Dry
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095
| | - Aaron W James
- School of Dentistry, University of California, Los Angeles, CA, 90095; Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095; Orthopedic Hospital Research Center, University of California, Los Angeles, CA, 90095.
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16
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Xu Z, Zuo Y, Wang J, Yu Z, Peng F, Chen Y, Dong Y, Hu X, Zhou Q, Ma H, Bao Y, Chen M. Overexpression of the regulator of G-protein signaling 5 reduces the survival rate and enhances the radiation response of human lung cancer cells. Oncol Rep 2015; 33:2899-907. [PMID: 25891540 DOI: 10.3892/or.2015.3917] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 01/13/2015] [Indexed: 11/05/2022] Open
Abstract
Regulator of G protein signaling 5 (RGS5) belongs to the R4 subfamily of RGS proteins, a family of GTPase activating proteins, which is dynamically regulated in various biological processes including blood pressure regulation, smooth muscle cell pathology, fat metabolism and tumor angiogenesis. Low-expression of RGS5 was reported to be associated with tumor progression in lung cancer. In the present study, we examined the potential roles of RGS5 in human lung cancer cells by overexpressing RGS5 in the cancer cells and further explored the underlying molecular mechanisms. The RGS5 gene was cloned and transfected into the human lung cancer cell lines A549 and Calu-3. The cells were tested for apoptosis with flow cytometry, for viability with MTT, for mobility and adhesion capacity. The radiosensitization effect of RGS5 was measured by a colony formation assay. The mechanisms of RGS5 functioning was also investigated by detection of protein expression with western blot analysis, including PARP, caspase 3 and 9, bax, bcl2, Rock1, Rock2, CDC42, phospho-p53 (Serine 15) and p53. The present study demonstrated that RGS5 overexpression remarkably induced apoptosis in human lung cancer cells, which was suggested to be through mitochondrial mechanisms. Overexpression of RGS5 resulted in significantly lower adhesion and migration abilities of the lung cancer cells (P<0.01). Furthermore, overexpression of RGS5 sensitized the lung cancer cells to radiation. In conclusion, the present study showed that RGS5 played an inhibitory role in human lung cancer cells through induction of apoptosis. Furthermore, RGS5 enhanced the cytotoxic effect of radiation in the human lung cancer cells. Our results indicated that RGS5 may be a potential target for cancer therapy.
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Affiliation(s)
- Zumin Xu
- Department of Radiation Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Yufang Zuo
- Cancer Center, Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong 524000, P.R. China
| | - Jin Wang
- Zhejiang Cancer Hospital, Hangzhou, Zhejiang 310012, P.R. China
| | - Zhonghua Yu
- Cancer Center, Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong 524000, P.R. China
| | - Fang Peng
- Department of Radiation Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Yuanyuan Chen
- Zhejiang Cancer Hospital, Hangzhou, Zhejiang 310012, P.R. China
| | - Yong Dong
- Cancer Center, Shilong People's Hospital, Dongguan City, Guangdong 523321, P.R. China
| | - Xiao Hu
- Department of Radiation Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Qichao Zhou
- Department of Radiation Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Honglian Ma
- Zhejiang Cancer Hospital, Hangzhou, Zhejiang 310012, P.R. China
| | - Yong Bao
- Department of Radiation Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Ming Chen
- Department of Radiation Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
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17
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Arnold C, Feldner A, Pfisterer L, Hödebeck M, Troidl K, Genové G, Wieland T, Hecker M, Korff T. RGS5 promotes arterial growth during arteriogenesis. EMBO Mol Med 2015; 6:1075-89. [PMID: 24972930 PMCID: PMC4154134 DOI: 10.15252/emmm.201403864] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Arteriogenesis—the growth of collateral arterioles—partially compensates for the progressive occlusion of large conductance arteries as it may occur as a consequence of coronary, cerebral or peripheral artery disease. Despite being clinically highly relevant, mechanisms driving this process remain elusive. In this context, our study revealed that abundance of regulator of G-protein signalling 5 (RGS5) is increased in vascular smooth muscle cells (SMCs) of remodelling collateral arterioles. RGS5 terminates G-protein-coupled signalling cascades which control contractile responses of SMCs. Consequently, overexpression of RGS5 blunted Gαq/11-mediated mobilization of intracellular calcium, thereby facilitating Gα12/13-mediated RhoA signalling which is crucial for arteriogenesis. Knockdown of RGS5 evoked opposite effects and thus strongly impaired collateral growth as evidenced by a blockade of RhoA activation, SMC proliferation and the inability of these cells to acquire an activated phenotype in RGS5-deficient mice after the onset of arteriogenesis. Collectively, these findings establish RGS5 as a novel determinant of arteriogenesis which shifts G-protein signalling from Gαq/11-mediated calcium-dependent contraction towards Gα12/13-mediated Rho kinase-dependent SMC activation. Subject Categories Vascular Biology & Angiogenesis
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Affiliation(s)
- Caroline Arnold
- Division of Cardiovascular Physiology, Institute of Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany
| | - Anja Feldner
- Division of Cardiovascular Physiology, Institute of Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany
| | - Larissa Pfisterer
- Division of Cardiovascular Physiology, Institute of Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany
| | - Maren Hödebeck
- Division of Cardiovascular Physiology, Institute of Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany
| | - Kerstin Troidl
- Department of Pharmacology, Max-Planck-Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Guillem Genové
- Division of Vascular Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Thomas Wieland
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Heidelberg, Mannheim, Germany
| | - Markus Hecker
- Division of Cardiovascular Physiology, Institute of Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany
| | - Thomas Korff
- Division of Cardiovascular Physiology, Institute of Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany
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18
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Woodard GE, Jardín I, Berna-Erro A, Salido GM, Rosado JA. Regulators of G-protein-signaling proteins: negative modulators of G-protein-coupled receptor signaling. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2015; 317:97-183. [PMID: 26008785 DOI: 10.1016/bs.ircmb.2015.02.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Regulators of G-protein-signaling (RGS) proteins are a category of intracellular proteins that have an inhibitory effect on the intracellular signaling produced by G-protein-coupled receptors (GPCRs). RGS along with RGS-like proteins switch on through direct contact G-alpha subunits providing a variety of intracellular functions through intracellular signaling. RGS proteins have a common RGS domain that binds to G alpha. RGS proteins accelerate GTPase and thus enhance guanosine triphosphate hydrolysis through the alpha subunit of heterotrimeric G proteins. As a result, they inactivate the G protein and quickly turn off GPCR signaling thus terminating the resulting downstream signals. Activity and subcellular localization of RGS proteins can be changed through covalent molecular changes to the enzyme, differential gene splicing, and processing of the protein. Other roles of RGS proteins have shown them to not be solely committed to being inhibitors but behave more as modulators and integrators of signaling. RGS proteins modulate the duration and kinetics of slow calcium oscillations and rapid phototransduction and ion signaling events. In other cases, RGS proteins integrate G proteins with signaling pathways linked to such diverse cellular responses as cell growth and differentiation, cell motility, and intracellular trafficking. Human and animal studies have revealed that RGS proteins play a vital role in physiology and can be ideal targets for diseases such as those related to addiction where receptor signaling seems continuously switched on.
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Affiliation(s)
- Geoffrey E Woodard
- Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, MD, USA; Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA
| | - Isaac Jardín
- Department of Physiology, University of Extremadura, Caceres, Spain
| | - A Berna-Erro
- Department of Physiology, University of Extremadura, Caceres, Spain
| | - Gines M Salido
- Department of Physiology, University of Extremadura, Caceres, Spain
| | - Juan A Rosado
- Department of Physiology, University of Extremadura, Caceres, Spain
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19
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Ganss R. Keeping the Balance Right. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 133:93-121. [DOI: 10.1016/bs.pmbts.2015.02.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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20
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Antiatherosclerotic effect of korean red ginseng extract involves regulator of g-protein signaling 5. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2014; 2014:985174. [PMID: 25610490 PMCID: PMC4290152 DOI: 10.1155/2014/985174] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 11/13/2014] [Accepted: 11/20/2014] [Indexed: 12/27/2022]
Abstract
Regulator of G-protein signaling 5 (RGS5), an inhibitor of Gα(q) and Gα(i) activation, has been reported to have antiatherosclerosis. Previous studies showed antiatherosclerotic effect of Korean red ginseng water extract (KRGE) via multiple signaling pathways. However, potential protective effect of KRGE through RGS5 expression has not been elucidated. Here, we investigated the antiatherosclerotic effect of KRGE in vivo and in vitro and its role on RGS5 mRNA expression. Elevated levels of total cholesterol, lactate dehydrogenase (LDH), and triglyceride (TG) in western diet groups of low-density lipoprotein receptor deficient LDLr(-/-) mice were reversed by oral administration of KRGE. KRGE suppressed transcriptional activity of tumor necrotic factor alpha (TNF-α), interleukin-6 (IL-6), and leptin in adipose tissue. It also potently repressed western diet-induced atheroma formation in aortic sinus. While KRGE showed reduced mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), IL-1β, IL-6, and TNF-α in LPS-stimulated RAW264.7 cells, it enhanced mRNA expression of RGS5. Moreover, RGS5 siRNA transfection of microglia cells pretreated with KRGE reversed its inhibitory effect on the expression of iNOS, COX-2, and IL-1β mRNA. In conclusion, KRGE showed antiatherosclerotic and anti-inflammatory effects in western diet fed LDLr(-/-) mice and this effect could partly be mediated by RGS5 expression.
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21
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Regulator of G-protein signaling-5 is a marker of hepatic stellate cells and expression mediates response to liver injury. PLoS One 2014; 9:e108505. [PMID: 25290689 PMCID: PMC4188519 DOI: 10.1371/journal.pone.0108505] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 08/22/2014] [Indexed: 12/11/2022] Open
Abstract
Liver fibrosis is mediated by hepatic stellate cells (HSCs), which respond to a variety of cytokine and growth factors to moderate the response to injury and create extracellular matrix at the site of injury. G-protein coupled receptor (GPCR)-mediated signaling, via endothelin-1 (ET-1) and angiotensin II (AngII), increases HSC contraction, migration and fibrogenesis. Regulator of G-protein signaling-5 (RGS5), an inhibitor of vasoactive GPCR agonists, functions to control GPCR-mediated contraction and hypertrophy in pericytes and smooth muscle cells (SMCs). Therefore we hypothesized that RGS5 controls GPCR signaling in activated HSCs in the context of liver injury. In this study, we localize RGS5 to the HSCs and demonstrate that Rgs5 expression is regulated during carbon tetrachloride (CCl4)-induced acute and chronic liver injury in Rgs5LacZ/LacZ reporter mice. Furthermore, CCl4 treated RGS5-null mice develop increased hepatocyte damage and fibrosis in response to CCl4 and have increased expression of markers of HSC activation. Knockdown of Rgs5 enhances ET-1-mediated signaling in HSCs in vitro. Taken together, we demonstrate that RGS5 is a critical regulator of GPCR signaling in HSCs and regulates HSC activation and fibrogenesis in liver injury.
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22
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Mahoney WM, Gunaje J, Daum G, Dong XR, Majesky MW. Regulator of G-protein signaling - 5 (RGS5) is a novel repressor of hedgehog signaling. PLoS One 2013; 8:e61421. [PMID: 23637832 PMCID: PMC3630190 DOI: 10.1371/journal.pone.0061421] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 03/10/2013] [Indexed: 01/11/2023] Open
Abstract
Hedgehog (Hh) signaling plays fundamental roles in morphogenesis, tissue repair, and human disease. Initiation of Hh signaling is controlled by the interaction of two multipass membrane proteins, patched (Ptc) and smoothened (Smo). Recent studies identify Smo as a G-protein coupled receptor (GPCR)-like protein that signals through large G-protein complexes which contain the Gαi subunit. We hypothesize Regulator of G-Protein Signaling (RGS) proteins, and specifically RGS5, are endogenous repressors of Hh signaling via their ability to act as GTPase activating proteins (GAPs) for GTP-bound Gαi, downstream of Smo. In support of this hypothesis, we demonstrate that RGS5 over-expression inhibits sonic hedgehog (Shh)-mediated signaling and osteogenesis in C3H10T1/2 cells. Conversely, signaling is potentiated by siRNA-mediated knock-down of RGS5 expression, but not RGS4 expression. Furthermore, using immuohistochemical analysis and co-immunoprecipitation (Co-IP), we demonstrate that RGS5 is present with Smo in primary cilia. This organelle is required for canonical Hh signaling in mammalian cells, and RGS5 is found in a physical complex with Smo in these cells. We therefore conclude that RGS5 is an endogenous regulator of Hh-mediated signaling and that RGS proteins are potential targets for novel therapeutics in Hh-mediated diseases.
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Affiliation(s)
- William M. Mahoney
- Department of Pathology, University of Washington, Seattle, Washington, United States of America
- Center for Cardiovascular Biology, University of Washington, Seattle, Washington, United States of America
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, Washington, United States of America
- * E-mail: (WMM); (MWM)
| | - Jagadambika Gunaje
- Department of Pathology, University of Washington, Seattle, Washington, United States of America
- Center for Cardiovascular Biology, University of Washington, Seattle, Washington, United States of America
| | - Guenter Daum
- Department of Surgery, University of Washington, Seattle, Washington, United States of America
- Center for Cardiovascular Biology, University of Washington, Seattle, Washington, United States of America
| | - Xiu Rong Dong
- Seattle Children’s Research Institute, University of Washington, Seattle, Washington, United States of America
| | - Mark W. Majesky
- Department of Pathology, University of Washington, Seattle, Washington, United States of America
- Department of Pediatrics, University of Washington, Seattle, Washington, United States of America
- Center for Cardiovascular Biology, University of Washington, Seattle, Washington, United States of America
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, Washington, United States of America
- Seattle Children’s Research Institute, University of Washington, Seattle, Washington, United States of America
- * E-mail: (WMM); (MWM)
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23
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Patel J, Channon KM, McNeill E. The downstream regulation of chemokine receptor signalling: implications for atherosclerosis. Mediators Inflamm 2013; 2013:459520. [PMID: 23690662 PMCID: PMC3649756 DOI: 10.1155/2013/459520] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 03/12/2013] [Indexed: 12/13/2022] Open
Abstract
Heterotrimeric G-protein-coupled receptors (GPCRs) are key mediators of intracellular signalling, control numerous physiological processes, and are one of the largest class of proteins to be pharmacologically targeted. Chemokine-induced macrophage recruitment into the vascular wall is an early pathological event in the progression of atherosclerosis. Leukocyte activation and chemotaxis during cell recruitment are mediated by chemokine ligation of multiple GPCRs. Regulation of GPCR signalling is critical in limiting vascular inflammation and involves interaction with downstream proteins such as GPCR kinases (GRKs), arrestin proteins and regulator of G-protein signalling (RGS) proteins. These have emerged as new mediators of atherogenesis by functioning in internalisation, desensitisation, and signal termination of chemokine receptors. Targeting chemokine signalling through these proteins may provide new strategies to alter atherosclerotic plaque formation and plaque biology.
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Affiliation(s)
- Jyoti Patel
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Keith M. Channon
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Eileen McNeill
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
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Holobotovskyy V, Manzur M, Tare M, Burchell J, Bolitho E, Viola H, Hool LC, Arnolda LF, McKitrick DJ, Ganss R. Regulator of G-protein signaling 5 controls blood pressure homeostasis and vessel wall remodeling. Circ Res 2013; 112:781-91. [PMID: 23303165 DOI: 10.1161/circresaha.111.300142] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE Regulator of G-protein signaling 5 (RGS5) modulates G-protein-coupled receptor signaling and is prominently expressed in arterial smooth muscle cells. Our group first reported that RGS5 is important in vascular remodeling during tumor angiogenesis. We hypothesized that RGS5 may play an important role in vessel wall remodeling and blood pressure regulation. OBJECTIVE To demonstrate that RGS5 has a unique and nonredundant role in the pathogenesis of hypertension and to identify crucial RGS5-regulated signaling pathways. METHODS AND RESULTS We observed that arterial RGS5 expression is downregulated with chronically elevated blood pressure after angiotensin II infusion. Using a knockout mouse model, radiotelemetry, and pharmacological inhibition, we subsequently showed that loss of RGS5 results in profound hypertension. RGS5 signaling is linked to the renin-angiotensin system and directly controls vascular resistance, vessel contractility, and remodeling. RGS5 deficiency aggravates pathophysiological features of hypertension, such as medial hypertrophy and fibrosis. Moreover, we demonstrate that protein kinase C, mitogen-activated protein kinase/extracellular signal-regulated kinase, and Rho kinase signaling pathways are major effectors of RGS5-mediated hypertension. CONCLUSIONS Loss of RGS5 results in hypertension. Loss of RGS5 signaling also correlates with hyper-responsiveness to vasoconstrictors and vascular stiffening. This establishes a significant, distinct, and causal role of RGS5 in vascular homeostasis. RGS5 modulates signaling through the angiotensin II receptor 1 and major Gαq-coupled downstream pathways, including Rho kinase. So far, activation of RhoA/Rho kinase has not been associated with RGS molecules. Thus, RGS5 is a crucial regulator of blood pressure homeostasis with significant clinical implications for vascular pathologies, such as hypertension.
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Affiliation(s)
- Vasyl Holobotovskyy
- Western Australian Institute for Medical Research, Rear, 50 Murray St, Perth, WA 6010, Australia
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Kach J, Sethakorn N, Dulin NO. A finer tuning of G-protein signaling through regulated control of RGS proteins. Am J Physiol Heart Circ Physiol 2012; 303:H19-35. [PMID: 22542620 DOI: 10.1152/ajpheart.00764.2011] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Regulators of G-protein signaling (RGS) proteins are GTPase-activating proteins (GAP) for various Gα subunits of heterotrimeric G proteins. Through this mechanism, RGS proteins regulate the magnitude and duration of G-protein-coupled receptor signaling and are often referred to as fine tuners of G-protein signaling. Increasing evidence suggests that RGS proteins themselves are regulated through multiple mechanisms, which may provide an even finer tuning of G-protein signaling and crosstalk between G-protein-coupled receptors and other signaling pathways. This review summarizes the current data on the control of RGS function through regulated expression, intracellular localization, and covalent modification of RGS proteins, as related to cell function and the pathogenesis of diseases.
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Affiliation(s)
- Jacob Kach
- Department of Medicine, University of Chicago, Illinois, 60637, USA
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26
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Wang JH, Huang WS, Hu CR, Guan XX, Zhou HB, Chen LB. Relationship between RGS5 expression and differentiation and angiogenesis of gastric carcinoma. World J Gastroenterol 2010; 16:5642-6. [PMID: 21105200 PMCID: PMC2992685 DOI: 10.3748/wjg.v16.i44.5642] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To explore the regulator of G-protein signaling 5 (RGS5) expression in gastric carcinoma and its association with differentiation and microvascular density (MVD).
METHODS: Expression of RGS5 and CD34 were examined in 76 cases of gastric carcinoma, including 22 cases with lymph node metastasis and 54 cases without lymph node metastasis determined by immunohistochemistry (IHC). MVD was assessed using CD34 monoclonal antibody. The presence of RGS5 and CD34 was analyzed by IHC using the Envision technique.
RESULTS: The RGS5 expression in gastric carcinoma was positively correlated with the differentiation of the tumor (r = 0.345, P < 0.001), but not related with age, gender, tumor size, clinical stage and lymph node metastasis (P > 0.05). The average MVD in the group with lymph node metastasis was significantly higher than that in the group without lymph node metastasis (P < 0.05). RGS5 expression was negatively correlated with the average MVD (P < 0.05).
CONCLUSION: RGS5 expression level in gastric carcinoma is associated with the differentiation and MVD of the tumor, and may be used as an important parameter for determining the prognosis of gastric carcinoma patients.
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27
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Seo D, Goldschmidt-Clermont P, Goldschidt-Clermont P, Velazquez O, Beecham G. Genomics of premature atherosclerotic vascular disease. Curr Atheroscler Rep 2010; 12:187-93. [PMID: 20425258 DOI: 10.1007/s11883-010-0104-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Atherosclerotic vascular disease is a systemic process with a common pathophysiology but with different disease manifestations depending on the vascular site. Over the past two decades, significant efforts have gone toward determining the genomic factors contributing to atherosclerotic vascular disease. Substantial information has been generated regarding the genomics of atherosclerotic coronary heart disease, and recently, several genomic analyses have looked at the cerebrovascular and peripheral vascular beds. This article reviews genomic investigations of atherosclerotic vascular disease in the coronary, cerebrovascular, and peripheral arteries. In this review, we have tried to restrict the discussion to studies of premature atherosclerosis, particularly those using non-biased genomic techniques.
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Affiliation(s)
- David Seo
- University of Miami Miller School of Medicine, 1501 NW 10th Ave, 809 Biomedical Research Building, Miami, FL 33136, USA.
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28
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Xiao B, Zhang Y, Niu WQ, Gao PJ, Zhu DL. Haplotype-based association of regulator of G-protein signaling 5 gene polymorphisms with essential hypertension and metabolic parameters in Chinese. Clin Chem Lab Med 2010; 47:1483-8. [PMID: 19863299 DOI: 10.1515/cclm.2009.344] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND A recent genome-wide linkage study mapped blood pressure (BP)-related loci on human chromosome 1q and identified the regulator of G-protein signaling 5 (RGS5) as a candidate for regulation of BP. Thus, we assessed the relationship between RGS5 genetic polymorphisms and essential hypertension (EH) in Chinese. METHODS A total of 906 patients with EH and 894 age- and gender-matched normotensive (NT) controls were enrolled. Sixteen single nucleotide polymorphisms (SNPs) in RGS5 were genotyped. RESULTS There were no significant differences in the overall distributions of the genotypic and allelic frequencies for each SNPs between the two groups. However, in haplotype analysis, significant differences for the overall distributions were noted for four haplotypes constructed by five SNPs (rs12041294C/T, rs10917690A/G, rs10917695T/C, rs10917696T/C and rs2662774G/A), viz. H(2) (C-A-C-T-A) (p=0.038), H(5) (C-G-T-T-G) (p=0.001), H(6) (T-G-C-T-A) (p=0.021) and H(12) (T-A-T-T-G) (p=0.023). Serum concentrations of high- and low-density lipoprotein cholesterol showed significant associations with haplotypes revealed by a global test (p=0.0001 and 0.0309). CONCLUSIONS Multiple SNPs in combination in RGS5 may confer risk for hypertension. Our results also lend support for the effect of RGS5 SNPs on lipid metabolism. Further studies are warranted to find the causal SNPs in RGS5 for EH.
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Affiliation(s)
- Bing Xiao
- State Key Laboratory of Medical Genomics, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, PR China
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29
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Abstract
Regulators of G protein signaling (RGS) proteins are important modulators of G protein-coupled receptors and, therefore, critical for cardiovascular functions. One family member, RGS5, has recently been identified as a key regulator of vascular remodeling and pericyte maturation in tumors. Here, we discuss a potential role for RGS5 and its relatives, RGS2 and 4, within the cardiovascular system. Insights into RGS5 signaling are likely to be highly significant for vascular pathologies such as hypertension, atherosclerosis, and angiogenesis.
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Affiliation(s)
- Mitali Manzur
- Western Australian Institute for Medical Research, The University of Western Australia Centre for Medical Research, Perth, Western Australia 6000, Australia
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30
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Kenagy RD, Fukai N, Min SK, Jalikis F, Kohler TR, Clowes AW. Proliferative capacity of vein graft smooth muscle cells and fibroblasts in vitro correlates with graft stenosis. J Vasc Surg 2009; 49:1282-8. [PMID: 19307078 DOI: 10.1016/j.jvs.2008.12.020] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2008] [Revised: 12/04/2008] [Accepted: 12/07/2008] [Indexed: 11/18/2022]
Abstract
OBJECTIVE About a quarter of peripheral vein grafts fail due in part to intimal hyperplasia. The proliferative capacity and response to growth inhibitors of medial smooth muscle cells and adventitial fibroblasts in vitro were studied to test the hypothesis that intrinsic differences in cells of vein grafts are associated with graft failure. METHODS Cells were grown from explants of the medial and adventitial layers of samples of vein grafts obtained at the time of implantation. Vein graft patency and function were monitored over the first 12 months using ankle pressures and Duplex ultrasound to determine vein graft status. Cells were obtained from veins from 11 patients whose grafts remained patent (non-stenotic) and from seven patients whose grafts developed stenosis. Smooth muscle cells (SMCs) derived from media and fibroblasts derived from adventitia were growth arrested in serum-free medium and then stimulated with 1 muM sphingosine-1-phosphate (S1P), 10 nM thrombin, 10 ng/ml epidermal growth factor (EGF), 10 ng/ml platelet-derived growth factor-BB (PDGF-BB), PDGF-BB plus S1P, or PDGF-BB plus thrombin for determination of incorporation of [(3)H]-thymidine into DNA. Cells receiving PDGF-BB or thrombin were also treated with or without 100 microg/ml heparin, which is a growth inhibitor. Cells receiving thrombin were also treated with or without 150 nM AG1478, an EGF receptor kinase inhibitor. RESULTS SMCs and fibroblasts from veins of patients that developed stenosis responded more to the growth factors, such as PDGF-BB alone or in combination with thrombin or S1P, than cells from veins of patients that remained patent (P = .012). In addition, while PDGF-BB-mediated proliferation of fibroblasts from grafts that remained patent was inhibited by heparin (P < .03), PDGF-BB-mediated proliferation of fibroblasts from veins that developed stenosis was not (P > .5). CONCLUSION Inherent differences in the proliferative response of vein graft cells to PDGF-BB and heparin may explain, in part, the variability among patients regarding long term patency of vein grafts.
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MESH Headings
- Aged
- Ankle/blood supply
- Becaplermin
- Blood Pressure
- Cell Proliferation/drug effects
- Cells, Cultured
- Constriction, Pathologic
- DNA Replication
- Epidermal Growth Factor/metabolism
- Female
- Fibroblasts/drug effects
- Fibroblasts/metabolism
- Fibroblasts/pathology
- Graft Occlusion, Vascular/etiology
- Graft Occlusion, Vascular/pathology
- Graft Occlusion, Vascular/physiopathology
- Heparin/pharmacology
- Humans
- Hyperplasia
- Lower Extremity/blood supply
- Lysophospholipids/metabolism
- Male
- Middle Aged
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- Peripheral Vascular Diseases/pathology
- Peripheral Vascular Diseases/physiopathology
- Peripheral Vascular Diseases/surgery
- Platelet-Derived Growth Factor/metabolism
- Protein Kinase Inhibitors/pharmacology
- Proto-Oncogene Proteins c-sis
- Quinazolines
- Saphenous Vein/drug effects
- Saphenous Vein/pathology
- Saphenous Vein/physiopathology
- Saphenous Vein/transplantation
- Sphingosine/analogs & derivatives
- Sphingosine/metabolism
- Thrombin/metabolism
- Time Factors
- Tyrphostins/pharmacology
- Ultrasonography, Doppler, Duplex
- Vascular Patency
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Affiliation(s)
- Richard D Kenagy
- Department of Surgery, University of Washington Medical School, Seattle, Wash. 98195-6410, USA
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31
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RGS proteins: identifying new GAPs in the understanding of blood pressure regulation and cardiovascular function. Clin Sci (Lond) 2009; 116:391-9. [PMID: 19175357 DOI: 10.1042/cs20080272] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Understanding the mechanisms that underlie BP (blood pressure) variation in humans and animal models may provide important clues for reducing the burden of uncontrolled hypertension in industrialized societies. High BP is often associated with increased signalling via G-protein-coupled receptors. Three members of the RGS (regulator of G-protein signalling) superfamily RGS2, RGS4 and RGS5 have been implicated in the attenuation of G-protein signalling pathways in vascular and cardiac myocytes, as well as cells of the kidney and autonomic nervous system. In the present review, we discuss the current state of knowledge regarding their differential expression and function in cardiovascular tissues, and the likelihood that one or more of these alleles are candidate hypertension genes. Together, findings from the studies described herein suggest that development of methods to modulate the expression and function of RGS proteins may be a possible strategy for the treatment and prevention of hypertension and cardiovascular disease.
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Abstract
G protein-coupled biological processes are important for an ever-increasing number of human diseases and require fine-tuning through accessory molecules such as the regulators of G protein signaling (RGS). RGS5, a marker for tumor-resident pericytes, was recently established as playing a pivotal role in vascular maturation and vessel remodeling during carcinogenesis. Remarkably, tumors arising in a RGS5-deficient background display vessels with normalized morphology and an overall improved blood flow. Furthermore, these morphologic changes also lead to dramatic improvements in lymphocyte access to tumors and success of antitumor immunotherapy. Here, we consider the implications of these findings, and how they contribute to enhancing our understanding of remodeling angiogenic vessels as means for improving anticancer therapies.
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Affiliation(s)
- Mitali Manzur
- Western Australian Institute for Medical Research, The University of Western Australia Centre for Medical Research, Perth, Western Australia, Australia
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33
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Histogenomics: association of gene expression patterns with histological parameters in kidney biopsies. Transplantation 2009; 87:290-5. [PMID: 19155987 DOI: 10.1097/tp.0b013e318191b4c0] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Several studies investigated the association of histologic scores of donor kidney biopsies obtained before engraftment with posttransplant outcomes. Discrimination and goodness of fit of these scores, however, is low. METHODS Thus, we sought to identify and elucidate the performance of molecular rather than histologic markers for this purpose using whole genome gene expression microarray experiments. RESULTS We identified 80 unique differentially regulated genes in 82 samples, showing no histologic damage versus those with histologic damage, based on the Chronic Allograft Damage Index (CADI) and acute tubular injury. Main biological categories enriched with up-regulated genes in damaged tissue were "immunity and defense," "cell communication," or "apoptosis." Interestingly, genes involved in cell structure, cell adhesion, and protein trafficking were specific for tubular atrophy. Histology (CADI score) explained only 14% of the variability of 1 year creatinine (adjusted R2 for panel-reactive antibodies, biopsy confirmed acute rejection, and sum of human leukocyte antigen mismatches) whereas a combination of three biomarkers without clinical covariables explained 28%. The three molecular markers are the NLR family, pyrin domain containing 2 (NLRP2), immunoglobulin J polypeptide, and the regulator of G-protein signaling 5. CONCLUSION In summary, we identified biomarkers in transplant kidney biopsies, which are predictive for medium-term allograft function.
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S1P receptor signalling and RGS proteins; expression and function in vascular smooth muscle cells and transfected CHO cells. Eur J Pharmacol 2008; 600:1-9. [PMID: 18854184 DOI: 10.1016/j.ejphar.2008.09.041] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2008] [Revised: 09/08/2008] [Accepted: 09/25/2008] [Indexed: 12/29/2022]
Abstract
Sphingosine-1-phosphate (S1P) signalling via G protein-coupled receptors is important for the regulation of cell function and differentiation. Specific Regulators of G protein Signalling (RGS) proteins modulate the function of these receptors in many cell types including vascular smooth muscle cells (VSMCs). Therefore, we investigated the role of altered expression levels of RGS proteins in S1P receptor function in VSMCs and transfected CHO cells. The mRNA expression of the S1P(1) receptor, RGS4 and RGS16 were down-regulated in VSMCs during phenotypic modulation induced by culturing, whereas mRNA levels of RGS2, RGS3, S1P(2) and S1P(3) receptors were unchanged. Interestingly, the expression level of RGS5 was transiently up-regulated. Despite major alterations in RGS levels, S1P-induced calcium elevation in VSMCs was not altered. Co-transfection of RGS2, RGS3, RGS4, RGS5 and RGS16 into CHO-Flp-In cells stably expressing the S1P(1) or S1P(3) receptor did not modify S1P-induced inhibition of cAMP accumulation to a major extent. Similar results were obtained with SEW2871, a selective S1P(1) receptor agonist. However, the inhibition of cAMP accumulation by the agonist FTY720-P via the S1P(1) receptor was significantly decreased by co-transfection with RGS5. These results indicate that mRNA of the S1P(1) receptor, RGS4, RGS5 and RGS16 is differentially regulated during phenotypic modulation. However, major alterations in RGS protein expression have only limited effect on S1P receptor function.
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Hendriks-Balk MC, Peters SLM, Michel MC, Alewijnse AE. Regulation of G protein-coupled receptor signalling: focus on the cardiovascular system and regulator of G protein signalling proteins. Eur J Pharmacol 2008; 585:278-91. [PMID: 18410914 DOI: 10.1016/j.ejphar.2008.02.088] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2008] [Revised: 01/18/2008] [Accepted: 02/06/2008] [Indexed: 11/17/2022]
Abstract
G protein-coupled receptors (GPCRs) are involved in many biological processes. Therefore, GPCR function is tightly controlled both at receptor level and at the level of signalling components. Well-known mechanisms by which GPCR function can be regulated comprise desensitization/resensitization processes and GPCR up- and downregulation. GPCR function can also be regulated by several proteins that directly interact with the receptor and thereby modulate receptor activity. An additional mechanism by which receptor signalling is regulated involves an emerging class of proteins, the so-called regulators of G protein signalling (RGS). In this review we will describe some of these control mechanisms in more detail with some specific examples in the cardiovascular system. In addition, we will provide an overview on RGS proteins and the involvement of RGS proteins in cardiovascular function.
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Affiliation(s)
- Mariëlle C Hendriks-Balk
- Department Pharmacology and Pharmacotherapy, Academic Medical Center, Amsterdam, The Netherlands
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36
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PPARdelta regulates multiple proinflammatory pathways to suppress atherosclerosis. Proc Natl Acad Sci U S A 2008; 105:4271-6. [PMID: 18337509 DOI: 10.1073/pnas.0711875105] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Lipid homeostasis and inflammation are key determinants in atherogenesis, exemplified by the requirement of lipid-laden, foam cell macrophages for atherosclerotic lesion formation. Although the nuclear receptor PPARdelta has been implicated in both systemic lipid metabolism and macrophage inflammation, its role as a therapeutic target in vascular disease is unclear. We show here that orally active PPARdelta agonists significantly reduce atherosclerosis in apoE(-/-) mice. Metabolic and gene expression studies reveal that PPARdelta attenuates lesion progression through its HDL-raising effect and anti-inflammatory activity within the vessel wall, where it suppresses chemoattractant signaling by down-regulation of chemokines. Activation of PPARdelta also induces the expression of regulator of G protein signaling (RGS) genes, which are implicated in blocking the signal transduction of chemokine receptors. Consistent with this, PPARdelta ligands repress monocyte transmigration and macrophage inflammatory responses elicited by atherogenic cytokines. These results reveal that PPARdelta antagonizes multiple proinflammatory pathways and suggest PPARdelta-selective drugs as candidate therapeutics for atherosclerosis.
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37
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PPARdelta-mediated antiinflammatory mechanisms inhibit angiotensin II-accelerated atherosclerosis. Proc Natl Acad Sci U S A 2008; 105:4277-82. [PMID: 18337495 DOI: 10.1073/pnas.0708647105] [Citation(s) in RCA: 174] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Activation of the nuclear hormone receptor peroxisome proliferator-activated receptor delta (PPARdelta) has been shown to improve insulin resistance, adiposity, and plasma HDL levels. However, its antiatherogenic role remains controversial. Here we report atheroprotective effects of PPARdelta activation in a model of angiotensin II (AngII)-accelerated atherosclerosis, characterized by increased vascular inflammation related to repression of an antiinflammatory corepressor, B cell lymphoma-6 (Bcl-6), and the regulators of G protein-coupled signaling (RGS) proteins RGS4 and RGS5. In this model, administration of the PPARdelta agonist GW0742 (1 or 10 mg/kg) substantially attenuated AngII-accelerated atherosclerosis without altering blood pressure and increased vascular expression of Bcl-6, RGS4, and RGS5, which was associated with suppression of inflammatory and atherogenic gene expression in the artery. In vitro studies demonstrated similar changes in AngII-treated macrophages: PPARdelta activation increased both total and free Bcl-6 levels and inhibited AngII activation of MAP kinases, p38, and ERK1/2. These studies uncover crucial proinflammatory mechanisms of AngII and highlight actions of PPARdelta activation to inhibit AngII signaling, which is atheroprotective.
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Abstract
RGS5 is a potent GTPase-activating protein for G(ialpha) and G(qalpha) that is expressed strongly in pericytes and is present in vascular smooth muscle cells. To study the role of RGS5 in blood vessel physiology, we generated Rgs5-deficient mice. The Rgs5(-/-) mice developed normally, without obvious defects in cardiovascular development or function. Surprisingly, Rgs5(-/-) mice had persistently low blood pressure, lower in female mice than in male mice, without concomitant cardiac dysfunction, and a lean body habitus. The examination of the major blood vessels revealed that the aortas of Rgs5(-/-) mice were dilated compared to those of control mice, without altered wall thickness. Isolated aortic smooth muscle cells from the Rgs5(-/-) mice exhibited exaggerated levels of phosphorylation of vasodilator-stimulated phosphoprotein and extracellular signal-regulated kinase in response to stimulation with either sodium nitroprusside or sphingosine 1-phosphate. The results of this study, along with those of previous studies demonstrating that RGS5 stability is under the control of nitric oxide via the N-end rule pathway, suggest that RGS5 may balance vascular tone by attenuating vasodilatory signaling in vivo in opposition to RGS2, another RGS (regulator of G protein signaling) family member known to inhibit G protein-coupled receptor-mediated vasoconstrictor signaling. Blocking the function or the expression of RGS5 may provide an alternative approach to treat hypertension.
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Wang X, Adams LD, Pabón LM, Mahoney WM, Beaudry D, Gunaje J, Geary RL, Deblois D, Schwartz SM. RGS5, RGS4, and RGS2 expression and aortic contractibility are dynamically co-regulated during aortic banding-induced hypertrophy. J Mol Cell Cardiol 2007; 44:539-50. [PMID: 18207159 DOI: 10.1016/j.yjmcc.2007.11.019] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Revised: 10/04/2007] [Accepted: 11/29/2007] [Indexed: 11/26/2022]
Abstract
Overexpression of regulator of G protein signaling 5 (RGS5) in arteries over veins is the most striking difference observed using microarray analysis. The obvious question is what arterial function might require RGS5. Based on functions of homologous proteins in regulating cardiac mass and G-protein-coupled receptor (GPCR) signaling, we proposed that RGS5 and vascular expressed RGS2 and RGS4 could participate in regulating arterial hypertrophy. We used the suprarenal abdominal aorta banding model to induce hypertension and hypertrophy. All 3 RGS messages were expressed in unmanipulated aorta with RGS5 predominating. After 2 days, thoracic aorta lost expression of RGS5, 4, and 2. At 1 week, all three returned to normal, and at 28 days, they increased many fold above normal. Valsartan blockade of angiotensin II (angII)/angII type 1 receptor signaling prevented upregulation of RGS messages but only delayed mass increases, implying wall mass regulation involves both angII-dependent and angII-independent pathways. The abdominal aorta showed less dramatic expression changes in RGS5 and 4, but not 2. Again, those changes were delayed by valsartan treatment with no mass changes. Thoracic aorta contraction to GPCR agonists was examined in aortic explant rings to identify vessel wall physiological changes. In 2-day aorta, the response to Galphaq/i agonists increased above normal, while 28-day aorta had attenuated induced contraction via Galphaq/i agonist, implicating a connection between RGS message levels and changes in GPCR-induced contraction. In vitro overexpression studies showed RGS5 inhibits angII-induced signaling in smooth muscle cells. This study is the first experimental evidence that changes in RGS expression and function correlate with vascular remodeling.
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Affiliation(s)
- Xi Wang
- University of Washington, Department of Pathology, Seattle, Washington 98109, USA
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Grayson TH, Ohms SJ, Brackenbury TD, Meaney KR, Peng K, Pittelkow YE, Wilson SR, Sandow SL, Hill CE. Vascular microarray profiling in two models of hypertension identifies caveolin-1, Rgs2 and Rgs5 as antihypertensive targets. BMC Genomics 2007; 8:404. [PMID: 17986358 PMCID: PMC2219888 DOI: 10.1186/1471-2164-8-404] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Accepted: 11/07/2007] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Hypertension is a complex disease with many contributory genetic and environmental factors. We aimed to identify common targets for therapy by gene expression profiling of a resistance artery taken from animals representing two different models of hypertension. We studied gene expression and morphology of a saphenous artery branch in normotensive WKY rats, spontaneously hypertensive rats (SHR) and adrenocorticotropic hormone (ACTH)-induced hypertensive rats. RESULTS Differential remodeling of arteries occurred in SHR and ACTH-treated rats, involving changes in both smooth muscle and endothelium. Increased expression of smooth muscle cell growth promoters and decreased expression of growth suppressors confirmed smooth muscle cell proliferation in SHR but not in ACTH. Differential gene expression between arteries from the two hypertensive models extended to the renin-angiotensin system, MAP kinase pathways, mitochondrial activity, lipid metabolism, extracellular matrix and calcium handling. In contrast, arteries from both hypertensive models exhibited significant increases in caveolin-1 expression and decreases in the regulators of G-protein signalling, Rgs2 and Rgs5. Increased protein expression of caveolin-1 and increased incidence of caveolae was found in both smooth muscle and endothelial cells of arteries from both hypertensive models. CONCLUSION We conclude that the majority of differences in gene expression found in the saphenous artery taken from rats with two different forms of hypertension reflect distinctive morphological and physiological alterations. However, changes in common to caveolin-1 expression and G protein signalling, through attenuation of Rgs2 and Rgs5, may contribute to hypertension through augmentation of vasoconstrictor pathways and provide potential targets for common drug development.
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Affiliation(s)
- T Hilton Grayson
- Division of Neuroscience, John Curtin School of Medical Research, Australian National University, Canberra, Australia.
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Bansal G, Druey KM, Xie Z. R4 RGS proteins: regulation of G-protein signaling and beyond. Pharmacol Ther 2007; 116:473-95. [PMID: 18006065 DOI: 10.1016/j.pharmthera.2007.09.005] [Citation(s) in RCA: 167] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2007] [Accepted: 09/18/2007] [Indexed: 12/21/2022]
Abstract
The regulators of G-protein signaling (RGS) proteins were initially characterized as inhibitors of signal transduction cascades initiated by G-protein-coupled receptors (GPCR) because of their ability to increase the intrinsic GTPase activity of heterotrimeric G proteins. This GTPase accelerating protein (GAP) activity enhances G protein deactivation and promotes desensitization. However, in addition to this signature trait, emerging data have revealed an expanding network of proteins, lipids, and ions that interact with RGS proteins and confer additional regulatory functions. This review highlights recent advances in our understanding of the physiological functions of one subfamily of RGS proteins with a high degree of homology (B/R4) gleaned from recent studies of knockout mice or cells with reduced RGS expression. We also discuss some of the newly appreciated interactions of RGS proteins with cellular factors that suggest RGS control of several components of G-protein-mediated pathways, as well as a diverse array of non-GPCR-mediated biological responses.
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Affiliation(s)
- Geetanjali Bansal
- Molecular Signal Transduction Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, United States
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Moroi K, Nishiyama M, Kawabata SI, Ichiba H, Yajima T, Kimura S. Phosphorylation of Ser166 in RGS5 by protein kinase C causes loss of RGS function. Life Sci 2007; 81:40-50. [PMID: 17540411 DOI: 10.1016/j.lfs.2007.04.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2007] [Revised: 03/31/2007] [Accepted: 04/17/2007] [Indexed: 11/30/2022]
Abstract
RGS5 is a member of regulators of G protein signaling (RGS) proteins that attenuate heterotrimeric G protein signaling by functioning as GTPase-activating proteins (GAPs). We investigated phosphorylation of RGS5 and the resulting change of its function. In 293T cells, transiently expressed RGS5 was phosphorylated by endogenous protein kinases in the basal state. The phosphorylation was enhanced by phorbol 12-myristate 13-acetate (PMA) and endothelin-1 (ET-1), and suppressed by protein kinase C (PKC) inhibitors, H7, calphostin C and staurosporine. These results suggest involvement of PKC in phosphorylation of RGS5. In in vitro experiments, PKC phosphorylated recombinant RGS5 protein at serine residues. RGS5 protein phosphorylated by PKC showed much lower binding capacity for and GAP activity toward Galpha subunits than did the unphosphorylated RGS5. In cells expressing RGS5, the inhibitory effect of RGS5 on ET-1-induced Ca(2+) responses was enhanced by staurosporine. Mass spectrometric analysis of the phosphorylated RGS5 revealed that Ser166 was one of the predominant phosphorylation sites. Substitution of Ser166 by aspartic acid abolished the binding capacity to Galpha subunits and the GAP activity, and markedly reduced the inhibitory effect on ET-1-induced Ca(2+) responses. These results indicate that phosphorylation at Ser166 of RGS5 by PKC causes loss of the function of RGS5 in G protein signaling. Since this serine residue is conserved in RGS domains of many RGS proteins, the phosphorylation at Ser166 by PKC might act as a molecular switch and have functional significance.
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Affiliation(s)
- Kayoko Moroi
- Department of Biochemistry and Molecular Pharmacology, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan
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Shirvani SM, Mookanamparambil L, Ramoni MF, Chin MT. Transcription factor CHF1/Hey2 regulates the global transcriptional response to platelet-derived growth factor in vascular smooth muscle cells. Physiol Genomics 2007; 30:61-8. [PMID: 17327490 DOI: 10.1152/physiolgenomics.00277.2006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The cardiovascular restricted transcription factor CHF1/Hey2 has been previously shown to regulate the smooth muscle response to growth factors. To determine how CHF1/Hey2 affects the smooth muscle response to growth factors, we performed a genomic screen for transcripts that are differentially expressed in wild-type and knockout smooth muscle cells after stimulation with platelet-derived growth factor. We screened 45,101 probes representing >39,000 transcripts derived from at least 34,000 genes, at eight different time points. We analyzed the expression data utilizing an algorithm based on Bayesian statistics to derive the best polynomial clustering model to fit the expression data. We found that in a total of 9,827 transcripts the normalized ratio of knockout to wild-type expression diverged more than threefold from baseline in at least one time point, and these transcripts separated into 17 distinct clusters. Further analysis of each cluster revealed distinct alterations in gene expression patterns for immediate early genes, transcription factors, matrix metalloproteinases, signaling molecules, and other molecules important in vascular biology. Our findings demonstrate that CHF1/Hey2 profoundly affects vascular smooth muscle phenotype by altering both the absolute expression level of a variety of genes and the kinetics of growth factor-induced gene expression.
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MESH Headings
- Animals
- Basic Helix-Loop-Helix Transcription Factors/genetics
- Cells, Cultured
- Mice
- Mice, Knockout
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Mutation
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Oligonucleotide Array Sequence Analysis
- Platelet-Derived Growth Factor/pharmacology
- Repressor Proteins/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Transcription, Genetic/drug effects
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Affiliation(s)
- Shervin M Shirvani
- Vascular Medicine Research, Cardiovascular Division, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
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Chang YPC, Liu X, Kim JDO, Ikeda MA, Layton MR, Weder AB, Cooper RS, Kardia SLR, Rao DC, Hunt SC, Luke A, Boerwinkle E, Chakravarti A. Multiple genes for essential-hypertension susceptibility on chromosome 1q. Am J Hum Genet 2007; 80:253-64. [PMID: 17236131 PMCID: PMC1785356 DOI: 10.1086/510918] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2006] [Accepted: 11/16/2006] [Indexed: 11/03/2022] Open
Abstract
Essential hypertension, defined as elevated levels of blood pressure (BP) without any obvious cause, is a major risk factor for coronary heart disease, stroke, and renal disease. BP levels and susceptibility to development of essential hypertension are partially determined by genetic factors that are poorly understood. Similar to other efforts to understand complex, non-Mendelian phenotypes, genetic dissection of hypertension-related traits employs genomewide linkage analyses of families and association studies of patient cohorts, to uncover rare and common disease alleles, respectively. Family-based mapping studies of elevated BP cover the large intermediate ground for identification of genes with common variants of significant effect. Our genomewide linkage and candidate-gene-based association studies demonstrate that a replicated linkage peak for BP regulation on human chromosome 1q, homologous to mouse and rat quantitative trait loci for BP, contains at least three genes associated with BP levels in multiple samples: ATP1B1, RGS5, and SELE. Individual variants in these three genes account for 2-5-mm Hg differences in mean systolic BP levels, and the cumulative effect reaches 8-10 mm Hg. Because the associated alleles in these genes are relatively common (frequency >5%), these three genes are important contributors to elevated BP in the population at large.
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Affiliation(s)
- Yen-Pei Christy Chang
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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Adams LD, Geary RL, Li J, Rossini A, Schwartz SM. Expression profiling identifies smooth muscle cell diversity within human intima and plaque fibrous cap: loss of RGS5 distinguishes the cap. Arterioscler Thromb Vasc Biol 2005; 26:319-25. [PMID: 16293795 DOI: 10.1161/01.atv.0000196647.45718.d6] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The fibrous cap of the atherosclerotic lesion is believed to be critical to stability because disruption of the cap is the final event leading to plaque rupture. We have, therefore, used expression arrays to define the phenotype of the cap and other plaque components. METHODS AND RESULTS To identify unique expression programs able to distinguish the smooth muscle of the cap from other plaque smooth muscle cells, RNA profiles were determined in human carotid artery media, nonatherosclerotic adjacent intima, fibrous cap of advanced atherosclerotic plaques, and whole advanced plaque with cDNA arrays covering 21,000 or 26,000 Unigene clusters. The molecular signature of each tissue was dominated by a core gene-set with differential expression of <1% of clusters assayed. CONCLUSIONS Both intima and cap expressed novel genes not previously associated with SMC pathology. If the cap is derived from a unique subpopulation, this pattern is the signature of that particular set of cells. The loss of RGS5 in the fibrous cap is of particular interest because of its role in vessel development and physiology.
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Affiliation(s)
- Lawrence D Adams
- Department of Pathology, Center for Cardiovascular Biology and Regenerative Medicine, University of Washington School of Medicine, Seattle, USA.
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