Identification of bioactive heterocyclic compounds from mulberry and their protective effect against streptozotocin-induced apoptosis in INS-1 cells.

A phytochemical investigation of the MeOH extracts from mulberries (the fruit of Morus alba L.) led to the identification of six heterocyclic compounds (1‑6). These compounds were screened to detect whether they protected pancreatic INS‑1 cells from streptozotocin (STZ)‑induced cytotoxicity. Compound 3 was the most effective at preventing STZ‑induced cytotoxicity and the production of reactive oxygen species (ROS) in INS‑1 cells. In addition, compound 3 effectively prevented apoptosis induced by STZ in INS‑1 cells. Compound 3 also prevented STZ‑mediated cleavage of caspase‑8, caspase‑3 and poly (ADP‑ribose) polymerase and increased the expression of B‑cell lymphoma‑2 (Bcl‑2), an anti‑apoptotic Bcl‑2 family protein. In conclusion, the results of the present study indicate that compound 3 extracted from the fruit of M. alba was highly effective in preventing type 1 diabetes mellitus and may be a novel treatment option.