Expression And Mechanism Of MiRNA-21 In Cardiac Fibroblasts Of Rats With Alcoholic Cardiomyopathy

Objective:By means of building a rodent model of ACM(alcoholic cardiomyopathy)to explore the expression and mechanism of miRNA-21 in cardiac fibroblasts of rats with ACM.Methods:16 adult male SD clean grade rats that weigh 200-250 g were randomly divided into the experimental group(8 rats)and the normal control group(8 rats).The rats were given an adaptive feeding for 1 week,fed with full-price pellets and freely drinking water.After 1 week,the rats in the experimental group were given liquor(20g/(kg.d))and intragastric administration twice a day;the normal control group used distilled water as a control,and observed the general condition of the animals and raised them for 15 days.After15days,a rat model of alcoholic cardiomyopathy was established.Echocardiography,serum myocardial enzymes and pathological examination were performed to determine the establishment of alcoholic cardiomyopathy model.RT-PCR was used to detect expression of miRNA-21 in myocardial tissue of each group.Immunohistochemistry was used to detect the expression of fibroblast factor 2 in myocardial tissue,compared with the normal control group,therefore,we explore the expression of miRNA-21 in cardiac fibroblasts of rats with ACM(alcoholic cardiomyopathy)and its mechanism.Results:The general state,the normal control group gained weight significantly and all survived.The weight gain of the experimental group was slow,even the weight of rats showed the negative growth,and the three died.There was no statistical difference in HW and HW/BW of rats(P > 0.05),but there was marked difference in BW(P<0.05).Echocardiography:Compared with normal control group,LVSD and LVDD were increased(P<0.05).Both LVEF and LVFS were lower(P<0.05)and both cardiac morphology indexes LVPWTs and LVPWTdwere decreased(P<0.05).The IVST of the experimental group was significantly reduced(P<0.05).Serum myocardial zymogram(AST,LDH,HBDH,CK):The study revealed that serum myocardial enzymes in the experimental group were higher than the normal control group(P<0.05).Histopathology Observations:According to pathological results,the HE staining in rats of the normal group was normal,while the experimental group rats were obviously different.HEstaining in the experimental group showed the hypertrophy,partial necrosis,muscle fiber rupture,and inflammatory cell infiltration in the experimental group,which was consistent with subclinical changes in alcoholic cardiomyopathy.RT-PCR:The expression of miRNA-21 in myocardium of the experimental group was significantly higher than that of the normal control group(P<0.05).Immunohistochemistry:The expression of fibroblast growth factor 2 in myocardial tissue of the experimental group was significantly up-regulated.Conclusions:It suggests that the rat model of ACM has been successfully established.miRNA-21 is involved in the pathogenesis of alcoholic cardiomyopathy,and over-expression of miRNA-21 may promote cardiac fibrosis by regulating the expression of fibroblast growth factor 2,finally it may regulate cardiac remodeling.