Effect Of Basic Fibroblast Growthfactor On Oxidative Stress Of Myocardium In Evirus B3Induced Viral Myocarditis Of Mice

Objective:To study the effect of basic fibroblast growth factor (bFGF) on oxidative stress of myocardium in coxsackievirusB3(CVB3) induced viral myocarditis(VMC) of mice.Methods:Male Balb/c mice were inoculated intraperitoneally with CVB3to reconstruct an animal model of myocarditis. Seventy-five male Balb/c mice were randomly divided into five groups (n=15):normal control group, VMC group, bFGF low-dose, middle-dose, high-dose intervention groups. bFGF was administrated by intramuscular injection (im). The mice were inoculated intraperitoneally with CVB3while im bFGF (the dosage of bFGF in three intervention groups were1000.0,2000.0,4000.0IU·kg-1, respectively) each day one time for six times. All mice were sacrificed at the seventh day after inoculated intraperitoneally with CVB3The pathological changes of myocardial tissues were observed with light microscope. The contents of superoxide anion (O2·-), hydrogen peroxide (H2O2), hydroxyl radical (·OH) and malondialdehyde (MDA) were determined by spectrophotometry in myocardial tissues. The contents of metallothionein (MT) and cardiac troponin I(cTnI) were determined by enzyme-linked immunosorbent assay method in myocardial tissues and serum respectively. The expressions of myocardial MT-ImRNA and MT-ⅡmRNA were detected by reverse transcription-real time fluorescent quantitative polymerase chain reaction method in myocardial tissues.Results:VMC group compared with normal control group:the contents of O2·-, H2O2,·OH, MDA and pathological scores in myocardial tissues, the content of cTnI in serum were significantly higher than those in normal control group(P<0.01), the expressive levels of MT-I mRNA, MT-Ⅱ mRNA and content of MT in myocardial tissues were significantly lower than those in normal control group(P<0.01). bFGF three intervention groups compared with VMC group:the contents of O2·-, H2O2,·OH, MDA and pathological scores in myocardial tissues, the content of cTnI in serum were significantly lower than those in VMC group(P<0.01), the expressive levels of MT-ImRNA, MT-IImRNA and content of MT in myocardial tissues were significantly higher than those in VMC group(P<0.01), the changes were obviously dose-dependent with bFGF in bFGF three intervention groups.Conclusion:bFGF inhibited the oxidative stress in myocardium induced by CVB3, and thereby reduced injury of myocardium induced by CVB3, this was related to bFGF antagonized the inhibitory effect of CVB3on the synthesis of MT in myocardium, thereby enhanced the scavenging capabilities of O2·-, H2O2,·OH in myocardium.