-The present study was designed to examine the potential antidiabetic and antioxidant effect of ethanol extract from Prunus mume fruit (PME) against alloxan-induced oxidative stress in pancreatic -cells, HIT-T15. To evaluate the antidiabetic effect of PME, 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazoliu bromide (MTT) cell proliferation assay, lactate dehydrogenase (LDH) release assay, NAD + /NADH ratio and insulin secretion were assessed. We also measured its antioxidant effect against alloxan-induced oxidative stress in the cells by assessing the levels of the antioxidant enzymes including superoxide dismutase (SOD), glutathione S-transferase (GST), glutathione reductase (GR) and glutathione peroxidase (GPx). The results of this analysis showed that alloxan significantly decreased cell viability, increased LDH leakage, and lowered NAD + /NADH ratio and insulin secretion in HIT-T15 cells. However, PME significantly increased the viability of alloxan-treated cells and lowered LDH leakage. The intracellular NAD + /NADH ratio and insulin secretion were also increased by 1.5~1.9-fold and 1.4-fold, respectively, after treatment with the PME. The HIT-T15 cells treated with alloxan showed significant decreases in the activities of antioxidant enzymes, while PME significantly elevated the levels of antioxidant enzymes. Based on these results, we suggest that PME could have a protective effect against the cytotoxicity and dysfunction of pancreatic β-cells in the presence of alloxan-induced oxidative stress.

The objective of the present study was to evaluate the potential antidiabetic and antioxidant effect of the ethanol extract from Chrysanthemum cornarium L. var. spatiosum(CSE) against alloxan-induced oxidative stress in pancreatic β-cells, HIT-T15. In this study, the antidiabetic effect of CSE was examined using the 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazoliu bromide(MTT) cell proliferation assay, lactate dehydrogenase(LDH) release assay, NAD + /NADH ratio and insulin secretion. To further investigate whether CSE is involved in the antioxidant activity of alloxan-damaged HIT-T15 cells, its antioxidant effect against alloxan-induced oxidative stress was measured in HIT-T15 cells by determining the levels of antioxidant enzymes including superoxide dismutase(SOD), glutathione S-transferase(GST), glutathione reductase(GR) and glutathione peroxidase(GPx). The results of this analysis showed that alloxan significantly decreased cell viability, increased LDH leakage, and lowered NAD + /NADH ratio and insulin secretion in HIT-T15 cells. However, CSE significantly increased the viability of alloxan-treated cells and lowered LDH leakage. The intracellular NAD + /NADH ratio and insulin secretion were also significantly increased by 1.7-fold and 1.3-fold, respectively, after treatment with 100 ㎍/㎖ CSE. The HIT-T15 cells treated with alloxan showed significant decreases in the activities of antioxidant enzymes, while CSE significantly elevated the levels of antioxidant enzymes. These findings suggest that CSE could have a protective effect against cytotoxicity and dysfunction of pancreatic cells in the presence of alloxan-induced oxidative stress.