摘要
BackgroundMyocardialfibrosisplaysacriticalroleintheprocessofdiabeticcardiacremolding.MicroRNAs(miRNAs)areendogenous,smallnon-codingRNAsthatnegativelyregulategeneexpressionindiversebiologicalandpathologicalprocesses.However,therolesofmiRNAsinmyocardialfibrosishavenotbeenwellelucidated.Inthepresentstudy,miRNAsprofilesinthefibroticmyocardiumofdb/dbmiceandmiRNAsexpressioninTGF-β1-stimulatedmousecardiacmyofibroblastswasexamined.MethodsHeartfunctionof18-week-olddb/dbmiceanddb/mcontrolmicewasdetectedbyechocardiography.miRNAexpressionprofileindiabeticmyocardiumwasdetectedbymiRNAmicroarray.Quantitativereal-timePCRwasusedtodeterminetheexpressionoffibrosis-relatedgenesandmiRNAprecursorsofinterest.Westernblotwasusedtodetectthelevelsoffibrosis-relatedproteins,activatedSmad3andtotalSmad3.ResultsTheresultofechocardiographyshowedthatleftventricularsystolicanddiastolicfunctionwasimpairedin18-week-olddb/dbmicewithoutsignificantchangeofejectionfraction(EF)andfractionalshortening(FS).Fibrosis-relatedgenesexpressionwasupregulatedandtheamountofphosphorylatedSmad3wasincreasedsignificantlyinthediabeticmyocardium.miRNAsdysregulationwasshownindiabeticmyocardium,sixty-eightmiRNAs,includingmiR-208b,miR-29b,miR-26bandmiR-30e,wereincreasedovertwo-fold,meanwhile,sixty-twomiRNAsweredecreasedmorethantwo-foldinthemyocardiumofdb/dbmicecomparedtodb/mcontrols.InparallelwithasignificantupregulationofCol1a1,Col3a1andCTGFmiRNAexpression,miR-208b,miR-29b,miR-26bandmiR-30eprecursorswerealsoshowntobeupregulatedinTGF-β1-inducedC57bl/6mousecardiacmyofibroblasts.ConclusionsmicroRNAsweredysregulatedindiabeticmyocardium,withtheactivationofTGF-β/smad3pathway,contributingtodiabeticmyocardialfibrosis.
出版日期
2012年01月11日（中国期刊网平台首次上网日期，不代表论文的发表时间）
