Polyopes lancifolia extracts protect INS-1 pancreatic β cells against high glucose level induced apoptosis

Polyopes lancifolia extracts were investigated for protection of INS-1 pancreatic beta cells against high glucose level-induced apoptosis using cell viability, lipid peroxidation generation, intracellular ROS, and NO assays. Expressions of the Bax and Bcl-2 proteins in INS-1 cells were evaluated using western blotting. Apoptosis induced by high glucose levels was determined based on analysis of FITC-annexin V/PI stained cells. A high glucose level-treatment induced INS-1 cells death. Cells treated with P. lancifolia extracts showed markedly reduced cytotoxicity in a dose-dependent manner, compared to the high glucose level-treated cells. Treatment with extracts dose-dependently decreased lipid peroxidation and intracellular ROS and NO levels, and increased cell viability in high glucose level-pretreated INS-1 cell, compared to the high glucose level-treated cells. Extract treatment significantly (p < 0.05) reduced the Bax protein level and increased the anti-apoptotic Bcl-2 protein level, compared with the high glucose leveltreated cells. P. lancifolia extract treatment reduced the apoptosis that is induced by a high level glucose-treatment, based on annexin V/PI staining.