Antioxidative effects of phenolic extracts from chestnut leaves, catkins and spiny burs in streptozotocin-treated rat pancreatic β-cells

Oxidative stress plays a central role in the onset of diabetes which is characterised by progressive pancreatic β-cell failure. We studied the ability of phenolic extracts prepared from chestnut leaf, catkin and spiny burs to prevent oxidative stress-induced β-cell (Rin-5F) death. The Rin-5F cell death was induced by treatment with the diabetogenic agent streptozotocin (STZ) and the protective effects of the chestnut extracts were assessed after cells treatment with a STZ/extracts mixture. The chestnut extracts increased cell viability by protecting DNA from oxidative damage and by enhancing the natural antioxidant system. Moreover, the chestnut extracts had a significant impact on the cell's redox-status which was observed as an increase in the levels of reduced glutathione. Chestnut extracts were capable of inhibiting lipid peroxidation, which was manifested as a lowering of malondialdehyde levels. We concluded that chestnut extracts increased cell viability after STZ treatment as a result of their antioxidative properties. © 2010 Elsevier Ltd