ABSTRACT
OBJECTIVE To investigate the effects of Angelica sinensis polysaccharide on the apoptosis of cardiomyocytes in diabetic KK-Ay mice. METHODS KK-Ay mice were randomly divided into model group， metformin group （200 mg/kg） and A. sinensis polysaccharide high-dose， medium-dose and low-dose groups （400， 200 and 100 mg/kg）； C57BL/6J mice were included in blank group， with 8 mice in each group. Each group was given relevant medicine intragastrically or normal saline， once a day， for consecutive 4 weeks. After the final administration， the levels of fasting glucose， total cholesterol （TC）， low-density lipoprotein cholesterol （LDL-C） and insulin （INS） were detected； the protein expressions of B-cell lymphoma 2 （Bcl-2）， cleaved- caspase-3， apoptosis signal-regulated kinase 1 （ASK1）， phosphorylated c-Jun N-terminal kinase （p-JNK）， phosphorylated inositol- requiring enzyme 1α （p-IRE1α） in myocardium， and apoptosis in cardiomyocytes were also detected. RESULTS Compared with model group， the fasting glucose， TC and LDL-C content， apoptotic rate of cardiomyocyte， protein expressions of p-JNK and p- IRE1α， ASK1， cleaved-caspase-3 were significantly lower in the metformin group and A. sinensis polysaccharide medium-dose， high-dose groups； INS level and relative expression of Bcl-2 protein were significantly increased （P＜0.05 or P＜0.01）. CONCLUSIONS A. sinensis polysaccharide can improve the levels of blood glucose and blood lipid and inhibit cardiomyocyte apoptosis in diabetic KK-Ay mice， and the mechanism may be related to the inhibition of IRE1/ASK1/JNK signaling pathway.