2 ',4 '-Dihydroxy-6 '-methoxy-3 ',5 '-dimethylchalcone inhibits apoptosis of MIN6 cells via improving mitochondrial function

State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, PR China.
Pharmazie (Impact Factor: 1.05). 09/2012; 67(9):798-803. DOI: 10.1691/ph.2012.1848
Source: PubMed


Mitochondrial dysfunction due to oxidative stress and concomitant beta-cell apoptosis may play a key role in type 2 diabetes. Inhibiting beta-cell apoptosis through ameliorating oxidative mitochondrial dysfunction with specific natural products may have preventive or therapeutic potential. In this study, the anti-apoptotic effect of 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC), a isolated chalcone from the buds of Cleistocalyx operculatus, on H2O2 induced MIN6 cells damage was investigated. Exposure to H2O2 at 250 microM for 3 h, the viability of MIN6 cells was significantly decreased and the apoptosis apparently occurred. A pre-treatment with DMC at the concentrations of 12.5-25 microM, before H2O2 addition, reduced nucleus fragmentation, decreased endogenous reactive oxygen species (ROS) production, and improved mitochondrial potential (MMP), and consequently, inhibited apoptosis. Furthermore, decreased activities of caspase-3 and caspase-9 were observed. These results clearly demonstrated DMC protected MIN6 cells against apoptosis due to its highly protective effect on mitochondria, and thus, it has great potential as a candidate drug for the diabetes care.

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