Effect of pretreatment with Rhizoma Alismatis extract on cardiac function and cysteinyl aspartate specific protease-3 in ischemia-reperfusion injury of rats

Abstract

Objective To observe the effect of pretreatment with Rhizoma Alismatis extract on cardiac function and cysteinyl aspartate specific protease-3(caspase-3)in ischemia-reperfusion injury of rats. Methods Male Sprague-Dawley(SD)rats were randomized into a sham-operated group(S group), an ischemia-reperfusion group(IR group), Rhizoma Alismatis water extract group(S1 group), Rhizoma Alismatis alcohol extract group(S2 group)and Rhizoma Alismatis polysaccharide group(S3 group). At the end of 14-day of intragastric gavages, rats were subjected to 40 min(T1)of LAD(left anterior descending)coronary artery ligation(ischemia)and 120 min(T2)of ligation loosening(reperfusion), called as myocardial ischemia-reperfusion(IR)models.Then, at the end of T1 and T2, the left ventricular end-diastolic pressure(LVEDP), left ventricular systolic pressure(LVSP), and maximum rise/fall rate of left intraventricular pressure(±dp/dtmax)were recorded respectively.The level of creatine kinase(CK)and lactate dehydrogenase(LDH)were determined.The area of myocardial infarction and the expression level of caspase-3 protein were tested. Results At end of T2, compared with the index values of IR group as a non-treatment control[LVEDP(6.70±0.22)mmHg, LVSP(86.16±15.11)mmHg, + dp/dtmax(997.99±151.03)mmHg, -dp/dtmax(663.71±68.55)mmHg, CK(10.54±2.04)U/L, LDH(296.51±7.00)U/L, the size of myocardial infarction(39.82±11.80)% and expression level of caspase-3(123.42±14.77)], the treatment groups of S1, S2, and S3 showed a lower levels of LVEDP[(5.89±0.47)mmHg, (5.89±0.67)mmHg, (6.07±0.51)mmHg], of activity of CK[(8.60±1.67)U/L(8.90±1.27)U/L, (9.39±0.83)U/L], of LDH[(239.33±30.81)U/L, (223.63±20.26)U/L, (241.19±45.56)U/L], of size of myocardial infarction[(30.39±5.44)%, (32.18±5.90)%, (33.12±8.16)%], and of expression level of caspase-3 protein[(73.44±15.28), (65.47±12.53), (65.05±10.45)], (all P<0.01 or<0.05); but showed a higher levels of LVSP[(99.24±12.00)mmHg, (97.05±12.45)mmHg, (97.06±7.61)mmHg], and of ±dp/dtmax[(1 137.33±85.70)mmHg, (1 147.24±118.07)mmHg, (1 124.50±141.47)mmHg]; [(604.77±68.37)mmHg, (616.61±46.73)mmHg, (708.76±81.44)mmHg], (all P<0.01 or<0.05). Conclusions Pretreatment with Rhizoma Alismatis extract can effectively improve the cardiac function of ischemic reperfusion injury in vivo in rats, and reduce myocardial infarction size and myocardial enzyme release.The mechanism may be related to the down-regulation of apoptotic protein caspase-3 in myocardial tissue. Key words: Myocardial reperfusion injury; Alisma; Cardiac function; Apoptosis