[The effect of Salvianolic Acid B on the Apoptosis of HUVECs Induced by Intermittent High Glucose].

Objective: To investigate the effect of Salvianolic acid B (Sal B) on the apoptosis of human umbilical vein endothelial cells (HUVECs) induced by intermittent high glucose and to explore the possible mechanisms.

Methods: HUVECs were preincubated with Sal B for 24 h, followed by incubation with intermittent high glucose (IHG, 5.5 mmol/L 12 h, 33.3 mmol/L 12 h) for 72 h. The viability of the HUVECs was determined by MTT assay, and the cells apoptosis was measured flow cytometry, respectively. The levels of nitric oxide (NO), total antioxidant capacity (T-AOC), malondialdehyde (MDA), and Caspase-3 activity were determined by colorimetric method. Intracellular ROS was evaluated by fluorescent microscopy. The protein levels of NOX4, p-eNOS, BAX, and BCL-2 were determined by Western-blot.

Results: Pretreatment with Sal B significantly ameliorated IHG-induced cells injury as was manifested by increased cell viability, up-regulated eNOS activation, and promoted the release of NO in HUVECs (P < 0.05 or P < 0.01). Sal B evidently suppressed IHG-induced cell apoptosis, down-regulated the expression of BAX protein and up-regulated the expression of BCL-2 protein. The activity of Capase-3 was also significantly reduced. Pre-incubation with Sal B led to a significant enhancement of antioxidant capacity and a reduction of NOX4 protein expression, accompanied by a remarkable decrease of intracellular ROS and MDA content (P < 0.05 or P < 0.01).

Conclusion: Sal B is capable of suppressing IHG-induced injury and apoptosis in HUVECs, which might be attributed to the attenuation of oxidative stress, regulation of BCL-2/BAX protein expression, and subsequent suppression of Caspase-3 activity.