The Protective Effects Of Apigenin On The Adriamycin-induced Myocardial Injury In Rats

Objective: To discuss the possible mechanism of adriamycin-induced myocardial injury in rats and the protective effects of apigenin on the adriamycin-induced myocardial injury, further provide the experimental basis for expanding the clinical uses of apigenin.Methods:(1)Male SD rats(n=40) were randomly divided into five groups:CONTROL,ADM,ADM+API(L),ADM+API(M),ADM+API(H).The rats in the ADM+API groups were respectively received apigenin by intraperitoneal injection of 7.5 mg/kg,15 mg/kg and 30 mg/kg for five days since the first day of experiment;the rats in the CONTROL andADMgroups were received N.S at the same volume for five days.All rats were received adriamycin by intraperitoneal injection of 15 mg/kg on the sixth day except the CONTROL group;the rats in the CONTROL group were received N.S at the same volume.All rats were put to death by removing the heads after taking the blood samples of orbital vein;partial free left ventricular tissues were cut for histologicalexamination. (2)ELISA was used to detect CK-MB content of serum; the morphology of cardiomyocyte was detected by the microscopy;TUNEL was used to detect the apoptosis of cardiomyocyte and AI was calculated;the immunohistochemistry stain method was used to detect the expression of TLR4, the results were indicated through GREY. (3)SPSS13.0 software was used to process the statistical analysis,the means were analyzed by One-Way ANOVA among all groups, Bonferroni method was used to analyze the means between any two groups.Results:(1)Under the microscope: the cardiomyocytes were arranged regularly , the transverse striation was distinct ,and the intercellular space was normal in the CONTROL group; the transverse striation of cardiomyocytes was obscure, myocardial fibers were twisted and split, and the intercellular space was wider in the ADM group; the myocardial damage was more significantly improved,and the degree to which the myocardial fibers were split was lighter in the ADM+API(M) and the ADM+API(H) groups than the ADM group, yet the damage of the ADM+API(L) was not significant. (2)In contrast with the CONTROL group,the values of AI and CK-MB increased,the expression of TLR4 increased(GREY reduced) in the ADM group (P<0.01);in contrast with the ADM group, the values of AI and CK-MB reduced, the expression of TLR4 reduced (GREY increased) in the ADM+API groups;the changes in the ADM+API(L) were not significant( P>0.05),yet the changes in the ADM+API(M) and the ADM+API(H) groups were significant (P<0.01). Conclusion:The increased apoptosis of cardiomyocytes and the expression of TLR4 involved in the adriamycin-induced cardiomyopathy.Apigenin could protect the rats against the adriamycin-induced cardiomyopathy,which possibly results from the reduction in the apoptosis of cardiomyocytes and the expression of TLR4.