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.

본 연구는 췌장베타세포인 HIT-T15 세포를 이용하여 매실주정추출물(PME)의 alloxan에 의한 산화스트레스로부터의 세포보호, 인슐린 분비능 및 항산화 효소 활성을 평가하였다. PME는 alloxan에 의해 유발된 산화스트레스로부터 세포를 보호하여 세포생존율을 증가시켰다. PME는 세포막 손상지표인 LDH 방출을 억제하였고 NAD+/NADH ratio를 유의적으로 증가시켜 세포사멸이 억제되어짐을 확인하였다. 또한 alloxan 단독처리군에 비해 250 μg/ml PME 처리군에서 인슐린 분비량이 유의성 있게 증가하였다. Alloxan과 PME를 동시에 처리하여 HIT-T15세포의 항산화효소 활성을 측정했을 때 산화스트레스에 의해 감소되었던 항산화효소 활성이 PME에 의해 보호되는 효과를 확인하였다. 이상의 연구결과로부터 PME는 세포괴사 및 DNA fragmentation을 억제하고 세포내 항산화효소 활성을 증가시켜 alloxan에 의해 유발된 산화스트레스로부터 췌장베타세포를 보호하고 이에 따른 인슐린 분비능 조절 효과가 있는 것으로 생각된다.