Effect and Mechanism of Panax quinnifolium Saponins on Myocardial Injury in Rats after Exhausted Exercise
To study the effects and mechanism of Panax quinnifolium saponins(PQS)on myocardial injury in rats after exhausted exercise,and to provide reference for the comprehensive utilization of PQS,rats were divided into normal control group,exhausted exercise group and low-,medium-and high dose PQS groups(100,200,400 mg/kg).All rats underwent exhausted swimming training except for the nor-mal control group,and the changes of related indexes were detected 4 weeks later.Results showed(1)compared with exhausted exercise group,LVIDs and LVIDd in medium-and high dose PQS groups were extremely decreased(P<0.0l),LVEF and LVFS in low-,medium-and high dose PQS groups were extremely increased(P<0.01),the content of cTnl in myocardial tissue and the activities of CTNK,LDH,ALT and α-HB-DH in serum in low-,medium-and high dose PQS groups were extremely decreased(P<0.01).LVIDs and LVIDd in medium-and high dose PQS groups were extremely lower than those in low dose group(P<0.01),LVEF in high dose PQS group was extremely higher than that in low-and medium dose group(P<0.01),LVFS in medium-and high dose PQS group were extremely higher than that in low dose group(P<0.01).The activities of CTNK and α-HBDH in medium-and high dose PQS groups were extremely lower than that in low dose group(P<0.01),the activity of LDH in high dose PQS group was extremely lower than that in low-and medium dose groups(P<0.01),and the activity of ALT in low-,medium-and high dose groups was significantly different(P<0.01).(2)Compared with exhausted exercise group,the MDA content in myocardial tissue and serum of low-,medium-and high dose PQS groups was significantly decreased(P<0.01),except that serum GSH-Px activity in low dose PQS group was significantly increased(P<0.05),the activities of SOD,CAT and GSH-Px in myocardial tissue and serum of other groups extremely in-creased(P<0.01).The MDA content in myocardial tissue and serum of high dose PQS group was signifi-cantly lower than those of low-and medium dose groups(P<0.01),the activities of SOD and CAT in high dose PQS groups were significantly higher than those of low-and medium dose groups(P<0.01),and the activity of GSH-Px in medium-and high dose PQS groups were significantly higher than those of low dose group(P<0.01).(3)Compared with exhausted exercise group,the apoptosis rate of myocardial tissue of low dose PQS group was significantly decreased(P<0.05),and the apoptosis rate of medium-and high dose groups and expressions of Bax and cleaved caspase-3 of low-,medium-and high dose groups were significantly decreased(P<0.01),while the expression of Bcl-2 was significantly increased(P<0.01).The apoptosis rate,and the expressions of Bax and cleaved caspase-3 in medium-and high dose PQS groups were significantly lower than those in low dose group(P<0.01),and the expression of Bcl-2 in medium-and high dose PQS groups was extremely higher than that in low dose group(P<0.01).This study reveals that the PQS can alleviate myocardial injury and improve cardiac function in rats after ex-hausted exercise,which is related to the inhibition of oxidative stress and anti-apoptosis of cardiomyocytes.