Curcumin protects PC12 cells from corticosterone-induced cytotoxicity: possible involvement of the ERK1/2 pathway

Antiglucocorticoid therapy in depressed patients is effective, which indicates that glucocorticoids play a key role in the occurrence of depression. Our previous work demonstrated the efficacy of curcumin in treating depression in rat and mouse models. We characterized the protective effects of curcumin against corticosterone-induced cytotoxicity in PC12 cells and explored the mechanisms of these protective effects in association with the phosphorylation and expression of ERK1/2 in PC12 cells. MTT assay showed that curcumin significantly protected PC12 cells from corticosterone-induced cytotoxicity. Curcumin at concentrations from 10(-8) to 10(-6) M rescued PC12 cells from corticosterone-induced cytotoxicity. Cell viability was increased more than 20% with curcumin treatment. Western blot analysis showed that corticosterone increased ERK1/2 phosphorylation in PC12 cells and curcumin 10(-9) M to 10(-6) M significantly inhibited corticosterone-induced ERK1/2 phosphorylation in PC12 cells in a dose-dependent manner. These results suggest that curcumin is able to protect PC12 cells which may be associated with inhibition of ERK phosphorylation.