title: Associations of MMP-2, BAX, and Bcl-2 mRNA and Protein Expressions with Development of Atrial Fibrillation.
abstract: BACKGROUND To examine changes of mRNA and protein expressions of MMP-2, Bcl-2, and BAX in atrial fibrillation (AF) patients, and investigate the correlations among these 3 biomarkers. MATERIAL AND METHODS Rheumatic heart disease patients (n=158) undergoing cardiac surgical procedures for mitral valve repair or replacement were included as the AF group (n=123), containing paroxysmal AF (n=42), persistent AF (n=36), and permanent AF (n=45). Rheumatic heart disease patients with sinus rhythm (SR) (n=35) were enrolled as the SR group (control group). Immunohistochemistry, Western blot, and real-time polymerase chain reaction (PCR) were applied to detect the protein and mRNA expression levels of MMP-2, Bcl-2, and BAX. Apoptosis was observed with light and electron microscopes and detected by TdT-mediated dUTP nick-end labeling (TUNEL). RESULTS Compared with the SR group, the left atrial diameters (LADs), protein and mRNA expression levels of MMP-2 and BAX, apoptotic index (AI), and Bcl-2/BAX ratio were evidently increased in the 3 AF groups, but protein and mRNA expression levels of Bcl-2 decreased in the AF groups (all P<0.05). Correlation analysis found that MMP-2 protein expression levels was positively correlated with BAX expression, but negatively correlated with Bcl-2 expression levels. CONCLUSIONS Our study results suggest that elevated MMP-2 expression and disturbance balance of Bcl-2/BAX expressions may be associated with the development and maintenance of AF. MMP-2 may be involved in the development of AF through promoting BAX expressions and inhibiting Bcl-2.
authors.affiliation: Department of Cardiology, The Affiliated Hospital of Binzhou Medical College, Binzhou, Shandong, China (mainland).
authors.forename: Shu-Ling
authors.initials: SL
authors.lastname: Diao
authors.affiliation: Department of Cardiology, The Affiliated Hospital of Binzhou Medical College, Binzhou, Shandong, China (mainland).
authors.forename: Hui-Pu
authors.initials: HP
authors.lastname: Xu
authors.affiliation: Department of Cardiology, The Affiliated Hospital of Binzhou Medical College, Binzhou, Shandong, China (mainland).
authors.forename: Bei
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Department of Cardiology, The Affiliated Hospital of Binzhou Medical College, Binzhou, Shandong, China (mainland).
authors.forename: Bao-Xin
authors.initials: BX
authors.lastname: Ma
authors.affiliation: Department of Geriatric Medicine, Qilu Hospital of Shandong University, Jinan, Shandong, China (mainland).
authors.forename: Xian-Liang
authors.initials: XL
authors.lastname: Liu
mesh_terms: D000368:Aged; D017209:Apoptosis; D001146:Arrhythmia, Sinus / Q000201:enzymology / Q000235:genetics / Q000473:pathology; D001281:Atrial Fibrillation / Q000201:enzymology* / Q000235:genetics* / Q000473:pathology; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000235:genetics* / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000235:genetics* / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D051028:bcl-2-Associated X Protein; D020778:Matrix Metalloproteinase 2