In Vitro Investigation of the Anti-Diabetic Effects of Imperialine on Beta-TC6 Pancreatic and C2C12 Skeletal Muscle Cell Lines

Imperialine (Imp) is a steroidal alkaloid present as the main active constituent of medicinal herb, Fritillaria imperialis with many biological and therapeutic effects. However, it has not been investigated in vitro for hypoglycemic effects. Herein, the effects of Imp on cell survival, carbohydrate-hydrolyzing enzymes (alpha-amylase and alpha-glucosidase), glucose uptake ability, insulin secretion levels, Advanced Glycation End products (AGEs) including pentosidine, methylglyoxal, and 3-deoxyglucosone levels and the activity of glyoxalase I as the main factor for degradation of AGEs were examined. C2C12 skeletal muscle and beta-TC6 pancreatic cells were incubated with Imp at concentrations of 0, 25, 50, 75, and 10 μg/ml and the cells were evaluated separately. The biological assays were based on ultraviolet-visible (UV/VIS) spectrophotometric and/or high-performance liquid chromatography (HPLC) methods. Imp had considerable and dose-dependent effects on glucose uptake and insulin secretion (P<0.05). The highest levels of glucose uptake were achieved at a concentration of 100 μg/ml of Imp. Increased glycation index, cytotoxicity, and decreased glyoxalase I activity appeared mostly at concentrations of 75 μg/ml and higher. The studied alkaloid demonstrated remarkable hypoglycemic effect by inhibition of alpha-amylase and alpha-glucosidase. Consequently, the results of the present study revealed possible hypoglycemic effects of Imp and it could be suggested for future studies in the treatment of diabetes mellitus.