Herbal formula SYJN protect PC12 cells from neurotoxicity induced by corticosterone

Aim of the study: SYJN is a Chinese herbal formula, containing four herbs: Bupleurum chinense DC., Curcuma aromatica Salisb., Perilla frutescens (Linn.) Britt. and Acorus tatarinowii Schott. Previous studies on the formula in our laboratory revealed an antidepressant-like effect on animal models of behavioral despair. However, the mechanisms underlying such antidepressant-like effect are yet to be understood. The aim of this work was to verify the previously established antidepressant-like effects on cell level using corticosterone-induced neurotoxicity in rat pheochromocytorna (PC12) cells to see if SYJN possesses any neuroprotective properties. Materials and methods: PC12 cells were treated with 200 mu M corticosterone in the absence or the presence of various concentrations of SYJN for 48 h. Then, cell viability, apoptosis, intracellular Ca2+ ([Ca2+]i) concentration and caspase-3 activity were determined. Results: Following the exposure of PC12 cells to 200 mu M corticosterone for 48 h, there were reductions in cell survival rate but increases in lactate dehydrogenase (LDH) release. In parallel, corticosterone caused significant elevations in DNA fragmentation, [Ca2+]i concentration and caspase-3 activity. However, when the PC12 cells were incubated with SYJN at different concentrations (10, 50 and 100 mg/L) in the presence of 200 mu M corticosterone for 48 h, the above effects were evidently alleviated in a dose-dependent manner. Conclusion: SYJN could generate a neuroprotective effect on corticosterone-induced neurotoxicity in PC12 cells, suggesting a possible action pathway of SYJN in vivo by decreasing the [Ca2+]i concentration and caspase-3 activity. (C) 2009 Elsevier Ireland Ltd. All rights reserved.