Anti-apoptotic effects of the medicinal plant Sterculia setigera in a model of serum deprivation-induced PC12 cells death

Sterculia setigera is a medicinal plant of Togolese flora. We have previously reported that S. setigera leaves dry hydroethanolic extract (SSE) protects in vitro cerebellar granule neurons against H2O2 and 6-OHDA-induced cell death and in vivo against ethanol neurotoxicity on the cerebellar cortex of 8-day-old Wistar rats. The present study aimed to extend our knowledge of the protective effects of SSE by exploring its anti-apoptotic mechanisms on cultured PC12 cells. Apoptosis was induced by serum depletion before treatment with various concentrations (5-100 mu g/mL) of SSE. SSE (20 mu g/mL) significantly protected PC12 cells (+51.8 %) against serum depletioninduced PC12 cell death and inhibited Caspase-3/7 (-65.1 %) activity. SSE also significantly increased the expression of the anti-apoptotic factor Bcl-2. Conversely, it repressed the expression of Casp-3, Tp53 and Ddit3. Taken together, these results indicate that inhibition of apoptosis appears to be one of the main mechanisms of S. setigera neuroprotective effects.