关键词: 丹酚酸B, 糖尿病, 血糖波动, 心肌损伤, 炎症

Abstract: Objective: To investigate the improvement effect of salvianolic acid B (Sal B) on myocardial injury in diabetic rats with blood glucose fluctuation and the possible mechanisms implicated. Methods: Diabetes rat model was induced by streptozotocin (STZ) plus high fat and high sugar diet. All the rats except those in control group were subjected to intraperitoneal injection of insulin or intragastric administration of glucose at indicated time to induce blood glucose fluctuation, while those in Sal B groups were supplemented intragastrically with sal B 160 mg/kg and 80 mg/kg, respectively. Six weeks later, fasting blood glucose (FBG) and levels of mean daily blood glucose (MBG), standard deviation of blood glucose (SDBG), largest amplitude of glycemic excursion (LAGE) were collected to measure the stability of blood glucose. The primary histopathological changes of myocardium tissue were observed by HE staining. Serum levels of interleukin-6 (IL-6) and lactic dehydrogenase (LDH) and myocardial contents of interleukin-1β (IL-1β), interleukin-18(IL-18) and cysteine aspartic acid specific protease-1 (Caspase-1) were evaluated by ELISA. Total anti-oxidant capacity (TAC) of myocardium tissue was determined with commercially available kits. Protein levels of nuclear factor-κB (NF-κB) and NOD-like receptor 3 (NLRP3) in myocardium tissue were examined by Western blotting analysis.Results: After 6 weeks of blood glucose fluctuation, FBG, MBG, SDBG and LAGE of diabetic rats were all increased more significantly than those in control group (P<0.01). Treatment with salvianolic acid B reduced level of FBG (P<0.05). Compared with the model group, treatment with sal B evidently ameliorated pathological changes of myocardium, accompanied by a significant increase of total antioxidant capacity(P<0.01), as well as decrease in levels of LDH, IL-6, IL-1β and IL-18 (P<0.05 or P<0.01). Sal B markedly down-regulated NF-κB nuclear translocation, protein expression of NLRP3 and activity of Caspase-1 in myocardium tissue (P<0.05 or P<0.01). Conclusion: Treatment with sal B can evidently ameliorate myocardium injury in diabetic rats with blood glucose fluctuation, which might be derived from suppression of NF-κB/NLRP3/Caspase-1 signaling pathway and inflammatory response.

Key words: salvianolic acid B, diabetes, blood glucose fluctuation, myocardium injury, inflammation