Lily Polysaccharide Prevents Alloxan-induced HIT-T15 Cell Damage by Reducing ROS Generation

The previous studies of our team and other researchers have shown that two polysaccharides derived from bulbs of lily aqueous extracts (LP-1, LP-2) can decrease fasting blood glucose concentration in diabetic model animal (in vivo). In the present study, we investigated the effects of LP-1 or LP-2 on cultured pancreatic d-cell tumor-derived cell line HIT-T15 that had undergone oxidative damage. The cell viability, insulin secretion, and intracellular reactive oxygen species (ROS) level were investigated in HIT-T15 cells after LP-, alloxan-, or both-treatment, respectively. The metabolic activity of d-cells was determined by MTT assay while the insulin secretion was detected by ELISA technique. Intracellular ROS was detected by fluorescent spectrophotometry using DCFH-DA. The treatment with LP-1 (>; 0.5 mg/ml) or LP-2 (>; 0.1 mg/ml) could significantly elevated the cell viability compared to untreated normal cells (p 1 mg/ml). Importantly, the viability of cells treated with 10 mg/ml LP-2 were almost restored to the levels of alloxan-untreated cells and completely prevented the lowering of glucose-stimulated insulin release. Our investigation suggested that LP-1 or LP-2 reduced the damage of alloxan-induced HIT-T15 cells through scavenging intracellular ROS level. And these data also provide some information when LP-1 or LP-2 is used as a bioactive component for developing a new anti-diabetic agent.