Effects of salvianolic acid B on proliferation, neurite outgrowth and differentiation of neural stem cells derived from the cerebral cortex of embryonic mice

Salvianolic acid B is isolated from Salvia miltiorrhiza , the root of which is widely used as a traditional Chinese medicine to treat stroke. However, little is known about how salvianolic acid B influences growth characteristics of neural stem cells (NSCs). The purpose of the present study was to evaluate the effects of salvianolic acid B on proliferation, neurite outgrowth and differentiation of NSCs derived from the cerebral cortex of embryonic mice using MTT, flow cytometry, immunofluorescence and RT-PCR. It was found that 20 μg mL −1 and 40 μg mL −1 salvianolic acid B had similar effects on proliferation of NSCs, and a suitable concentration of salvianolic acid B increased the number of NSCs and their derivative neurospheres. The growth-promoting activity of salvianolic acid B was dependent on and associated with an accumulation in the G2/S-phase cell population. Salvianolic acid B also promoted the neurite outgrowth of NSCs and their differentiation into neurons. The mRNA for tau, GFAP and nestin were present in differentiating neurospheres induced by salvianolic acid B. However, high-level expression of tau mRNA and low-level expression of GFAP mRNA was detected in differentiated cells, in contrast to the control conditions. This collective evidence indicates that exogenous salvianolic acid B is capable of promoting proliferation of neurospheres and differentiation towards the neuronal lineage in vitro and may act in the proliferation of NSCs and may promote NSC differentiation into neuronal cells.