Polygalasaponin G promotes neurite outgrowth of cultured neuron on myelin

Myelin contains many axonal outgrowth inhibitory components which contribute to regeneration failure after neuronal injury in the mammalian central nervous system (CNS). In an attempt to develop small molecular agents to promote axonal outgrowth, we screened a compound library purified from traditional Chinese herbs, and found a small molecular compound polygalasaponin G (PS-G), extracted from Polygala japonica, which has a potent neurotrophic activity on PC12 cells and cultured cortical neurons. We reported, to our knowledge for the first time, that PS-G could promote neurite outgrowth of neurons cultured on the myelin substrates and inhibit the activation of RhoA. Thus, our results could represent a therapeutic approach to improve axon regeneration after CNS injuries.