[Effects of 9,10-dihydroxysteatic acid on glucose metabolism in KKAy mice]

Objective: To study the effect of 9,10-dihydroxystearic acid (DHSA) on glucose tolerance and Insulin sensitivity in KKAy diabetic mice.

Methods: 48 male KKAy mice were randomly divided into four groups and were fed with high fat diet containing 4% DHSA, 2% DHSA, 4% Olive oil and 4% Corn oil, respectively. Glucose tolerance and Insulin sensitivity were measured after 5 and 6 weeks respectively. Effects of DHSA on activating PPAR-alpha and PPAR-gamma in CV-1 cells were also carried out.

Results: In glucose tolerance test, the blood glucose at 0.5 h and 1 h and the area under glucose curve in the group fed with 4% DHSA diet were significantly lower than those of other groups. In Insulin sensitivity test, the blood glucose level at 0.5 h and 1 h after injection of Insulin was lower in the 4% DHSA diet group, indicating the Insulin sensitivity of this group was obviously higher than other groups (P < 0.05). The body weight of the mice fed with 4% DHSA diet was much lower than those mice fed with 4% Corn diet (P < 0.05). 5 - 20 micromol/L DHSA did not activate PPAR-gamma in CV-1 cells but 50 - 100 micromol/L DHSA activated PPARgamma in a dose-dependent way although the activating effect of DHSA on PPARgamma was significantly lower than that of rosiglitazone. DHSA did not activate PPAR-alpha in CV-1 cells.

Conclusion: DHSA may improve glucose tolerance and Insulin sensitivity in KKAy mice and the effect might be related to the activation of PPAR-gamma by DHSA.