Figure 1.

Ginsenoside Rg1 (Rg1) promoted neurite outgrowth of cultured hippocampal neurons via ERK1/2 and PI3K/Akt signaling.

(A) Hippocampal neurons were observed by immunostaining for growth associated protein-43 after treatment with 50 μM Rg1 in the presence or absence of 10 μM API-2 (Akt inhibitor) or 10 μM PD98059 (MEK inhibitor) for 24 hours. (B–D) Neurite length was measured in primary cultures after treatment with Rg1 in the presence or absence of PD98059 or API-2 (B), or various concentrations of SB203580 (p38MAPK inhibitor; C) or SP600125 (JNK inhibitor; D) for 24 hours. Data are the mean ± SEM of five individual experiments. *P < 0.05, **P < 0.01, vs. control group (untreated cells); #P < 0.05, ##P < 0.01, vs. Rg1 (one-way analysis of variance followed by Newman-Keuls post hoc test). Scale bar in A: 200 μm.