Effect and Mechanism of Jiaotaiwan on Cognitive Impairment in Diabetic Mice / 中国实验方剂学杂志

ABSTRACT

Objective: To explore effect and mechanism of Jiaotaiwan (JTW) on cognitive impairment in diabetic mice. Method: The 40 db/db mice of spontaneous diabetes were randomly divided into model group, JTW 1 group (1.68 g·kg-1), JTW 2 group (3.36 g·kg-1), and JTW 3 group (8.40 g·kg-1), with 8 mice in each group, and 8 C57BL/6J mice were included into normal group. After 8 weeks of treatment, behavioral test,fasting blood glucose (FBG), fasting insulin (Fins), insulin resistance index (HOMA-IR), total triglyceride (TG), total cholesterol (TC), free fatty acids (FFA), high density lipoprotein (HDL), and low density lipoprotein (LDL) were detected. Western blot was used to detect protein expressions of pSer199, pSer202, pSer214, p-Akt, glycogen synthase kinase-3β(GSK-3β), phospho-GSK-3β(p-GSK-3β). Result: Compared with model group, FBG, Fins, HOMA-IR, TG, TC, HDL, FFA in JTW group decreased significantly (P0.01), with a significant improvement in cognitive function (P0.01), protein expressions of taupSer199, pSer202, pSer214 and GSK-3β in hippocampus of mice decreased significantly (PP0.01), and expressions of p-Akt and p-GSK3 beta significantly increased (P0.01). Conclusion: JTW 3 (Coptidis Rhizoma-Cinnamomi Cortex 10:1) can alleviate insulin resistance and cognitive impairment. The mechanism may be related to the inhibition of over-phosphorylation of tau protein, the down-regulation of GSK-3β protein expression and the up-regulation of p-Akt and p-GSK-3β expressions.