title: Regulator of G-protein signalling 5 protects against atherosclerosis in apolipoprotein E-deficient mice.
abstract: OBJECTIVE
  Atherosclerosis is a chronic inflammatory disease, in which 'vulnerable plaques' have been recognized as the underlying risk factor for coronary disease. Regulator of G-protein signalling (RGS) 5 controls endothelial cell function and inflammation. In this study, we explored the effect of RGS5 on atherosclerosis and the potential underlying mechanisms.
  
  
  METHODS
  RGS5(-/-) apolipoprotein E (ApoE)(-/-) and ApoE(-/-) littermates were fed a high-fat diet for 28 weeks. Total aorta surface and lipid accumulation were measured by Oil Red O staining and haematoxylin-eosin staining was used to analyse the morphology of atherosclerotic lesions. Inflammatory cell infiltration and general inflammatory mediators were examined by immunofluorescence staining. Apoptotic endothelial cells and macrophages were assayed with TUNEL. Expression of RGS5 and adhesion molecules, and ERK1/2 phosphorylation were evaluated by co-staining with CD31. Expression of mRNA and protein were determined by quantitative real-time PCR and Western blotting respectively.
  
  
  RESULTS
  Atherosclerotic phenotypes were significantly accelerated in RGS5(-/-) ApoE(-/-) mice, as indicated by increased inflammatory mediator expression and apoptosis of endothelial cells and macrophages. RGS5 deficiency enhanced instability of vulnerable plaques by increasing infiltration of macrophages in parallel with the accumulation of lipids, and decreased smooth muscle cell and collagen content. Mechanistically, increased activation of NF-κB and MAPK/ERK 1/2 could be responsible for the accelerated development of atherosclerosis in RGS5-deficient mice.
  
  
  CONCLUSIONS
  RGS5 deletion accelerated development of atherosclerosis and decreased the stability of atherosclerotic plaques partly through activating NF-κB and the MEK-ERK1/2 signalling pathways.
authors.affiliation: Key Laboratory of Cardiovascular Disease and Molecular Intervention, Key Laboratory of Human Functional Genomics, Atherosclerosis Research Centre, Nanjing Medical University, Nanjing, China.
authors.forename: Wen-Lin
authors.initials: WL
authors.lastname: Cheng
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China.|Cardiovascular Research Institute, Wuhan University, Wuhan, China.
authors.forename: Pi-Xiao
authors.initials: PX
authors.lastname: Wang
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China.|Cardiovascular Research Institute, Wuhan University, Wuhan, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China.|Cardiovascular Research Institute, Wuhan University, Wuhan, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China.|Cardiovascular Research Institute, Wuhan University, Wuhan, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Du
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China.|Cardiovascular Research Institute, Wuhan University, Wuhan, China.
authors.forename: Hongliang
authors.initials: H
authors.lastname: Li
authors.affiliation: Key Laboratory of Cardiovascular Disease and Molecular Intervention, Key Laboratory of Human Functional Genomics, Atherosclerosis Research Centre, Nanjing Medical University, Nanjing, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Ji
mesh_terms: D000818:Animals; D001057:Apolipoproteins E / Q000172:deficiency*; D050197:Atherosclerosis / Q000378:metabolism* / Q000517:prevention & control*; D051379:Mice; D018345:Mice, Knockout; D020710:RGS Proteins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*
chemical_list: D001057:Apolipoproteins E; D020710:RGS Proteins; C105346:Rgs5 protein, mouse