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

<i>Sterculia setigera</i> is a medicinal plant of Togolese flora. We have previously reported that <i>S. setigera</i> leaves dry hydroethanolic extract (SSE) protects <i>in vitro</i> cerebellar granule neurons against H₂O₂ and 6-OHDA-induced cell death and <i>in vivo</i> 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 µg/mL) of SSE. SSE (20 µg/mL) significantly protected PC12 cells (+51.8 %) against serum depletion-induced PC12 cell death and inhibited Caspase-3/7 (-65.1 %) activity. SSE also significantly increased the expression of the anti-apoptotic factor <i>Bcl-2</i>. Conversely, it repressed the expression of <i>Casp-3</i>, <i>Tp53</i> and <i>Ddit3</i>. Taken together, these results indicate that inhibition of apoptosis appears to be one of the main mechanisms of <i>S. setigera</i> neuroprotective effects.