Abstract
Context: Salvia miltiorrhiza Bge. (Labiatae) has been widely used for treating diabetes for centuries. Salvianolic acid B (SalB) is the main bioactive component in Salvia miltiorrhiza; however, its antidiabetic activity and possible mechanism are not yet clear.
Objective: To investigate the effects of SalB on glycometabolism, lipid metabolism, insulin resistance, oxidative stress, and glycogen synthesis in type 2 diabetic rat model.
Materials and methods: High-fat diet (HFD) and streptozotocin-induced diabetic rats were randomly divided into model group, SalB subgroups (50, 100, and 200 mg/kg), and rosiglitazone group.
Results: Compared with the model group, SalB (100 and 200 mg/kg) significantly decreased blood glucose (by 23.8 and 21.7%; p < 0.05 and p < 0.01) and insulin (by 31.3 and 26.6%; p < 0.05), and increased insulin sensitivity index (by 10.9 and 9.3%; p < 0.05). They also significantly decreased total cholesterol (by 24.9 and 27.9%; p < 0.01), low-density lipoprotein cholesterol (by 56.2 and 64.6%; p < 0.01), non-esterified fatty acids (by 32.1 and 37.9%; p < 0.01), hepatic glycogen (by 41.3 and 60.5%; p < 0.01), and muscle glycogen (by 33.2 and 38.6%; p < 0.05), and increased high-density lipoprotein cholesterol (by 50.0 and 61.4%; p < 0.05 and p < 0.01), which were originally altered by HFD and streptozotocin. In addition, SalB (200 mg/kg) markedly decreased triglyceride and malondialdehyde (by 31.5 and 29.0%; p < 0.05 and p < 0.01), and increased superoxide dismutase (by 56.6%; p < 0.01), which were originally altered by HFD and streptozotocin.
Discussion and conclusion: The results indicate that SalB can inhibit symptoms of diabetes mellitus in rats and these effects may partially be correlated with its insulin sensitivity, glycogen synthesis and antioxidant activities.
Declaration of interest
The authors have declared that there is no conflict of interest. This work was supported by the National Natural Science Foundation of China (81373940), the Specialized Research Fund for the Doctoral Program of Higher Education (20133519120001), and the Provincial Natural Science Foundation of Fujian (2012J05152 and 2012Y4005). The authors are grateful to Collaborative Innovation Center for Rehabilitation Technology and TCM Rehabilitation Research Center of SATCM for providing part financial support.