Abstract: Objective To investigate the effect of the Chinese herbal medicine Jin-Mai-Tong (JMT) on the differentiation of Schwann cells (SCs) under high-glucose conditions. Methods Primary Schwann cells were cultured to establish a high-glucose injury model, and intervened with JMT. The number of myelinating phenotype Schwann cells(MSCs) was counted; The protein expression levels of brain-derived neurotrophic factor(BDNF) and glial cell line-derived neurotrophic factor(GDNF) in culture supernatant were determined via ELISA; The expression levels of p38 mitogen-activated protein kinase(p38 MAPK), c-JUN, early growth response protein 2(EGR2) at both protein and mRNA levels were detected. Results The p38 MAPK pathway was activated under high-glucose conditions, accompanied by up regulated c-JUN protein expression and down regulated EGR2 expression. JMT extract significantly inhibited the activation of the p38 MAPK pathway, suppressed c-JUN protein expression, up regulated EGR2 expression, and increased the secretion of BDNF and GDNF proteins. Conclusions JMT can promote the differentiation of MSCs and increase the synthesis of neurotrophic factors by inhibiting the p38 MAPK pathway.

Key words: Jin-Mai-Tong, Schwann cell, p38 MAPK pathway, myelinating phenotype