Effects of Inula Britannica on myocardial caspase-3 and cytochrome C expression following overtraining-induced acute myocardial injury in rats

Abstract

Objective To investigate the effects of Inula Britannica on myocardial caspase-3 and cytochrome c ( cyt c) following overtraining-induced acute myocardial injury in rats.Methods Forty-eight male Wistar rats weighing 200-220 g were randomly divided into 3 groups:group control (group C,n =8) ; group exhausting swim (group E,n =24) and group Inula Britannica (group IB,n =16).The animal model of overtraining-indnced acute myocardial injury was developed by exhausting swim.The animals were forced to swim until they were exhausted.The animals sank to the bottom and no righting reflex or escape response was elicited when they were taken out of water in groups E and IB.In group IB oral Inula Britannica 25 ml/kg was given 24 h and immediately before overtraining.Blood samples were taken from inferior vena cava immediately and at 6,24 h after overtraining in group E and at 6,24 h after overtraining in group IB for determination of serum cardiac troponin I (cTnI) concentration (by ELISA).The animals were sacrificed after blood sampling and myocardial specimens were obtained for microscopic examination and determination of caspase-3 and cyt c expression (by immuno-histochemistry).Results Overtraining significantly increased serum cTnI concentration and up-regulated myocardial caspase-3 and cyt c expression in group E as compared with group C.Oral Inula Britannica significantly attenuated overtraining-induced increase in serum cTnI concentration and myocardial caspase-3 and cyt c expression in group IB as compared with group E.Conclusion Inula Britannica can reduce overtraining-induced acute myocardial injury by down-regulating caspase-3 and cyt c expression. Key words: Inula; Hyperkinesis; Cardiomyopathies; Cytochromes c; Caspase 3