ABSTRACT
Aim To investigate the effect of salvianolic acid B (Sal B)on c-Jun N-terminal kinase (JNK)ac-tivation and apoptosis of INS-1 cells induced by inter-mittent high glucose.Methods INS-1 cells were pre-incubated with Sal B for 24 h,followed by exposure to intermittent high glucose (IHG,11.1 mmol·L-1 12 h,33. 3 mmol·L-1 12 h)for 72 h.Cell viability was assessed by MTT assay and cell apoptosis was evalua-ted by flow cytometry.Glucose induced insulin secre-tion capacity and intracellular reactive oxygen species (ROS)contents were measured by enzyme linked im-munosorbent assay (ELISA)and a fluorescent probe DCFH-DA,respectively.Levels of JNK activation and PDX-1 protein expression were determined by Western blot analysis.Results Sal B significantly alleviated IHG-induced cell injury and apoptosis,with glucose induced insulin secretion capacity improved evidently (P<0.05 or P<0.01).Preincubation with Sal B no-tably decreased intracellular ROS and JNK activation in INS-1 cells,while the level of PDX-1 protein was in-creased markedly (P<0.05 or P<0.01 ).Conclu-sion Sal B is capable of ameliorating IHG-induced cell injury and apoptosis in INS-1 cells,which might be derived from suppression of JNK activation and up-regulation of PDX-1 protein expression.