Abstract: AIM: To investigate whether sesamol could improve inflammation and insulin resistance in adipose tissue of obese mice by regulating macrophage polarization. METHODS: An obese animal model was established in mice by inducing obesity with high-fat diet. The obese mice were administrated with sesamol (100 mg/kg) for 8 weeks. The mice were sacrificed after the intraperitoneal glucose tolerance test and insulin tolerance test, and the plasma lipid and insulin levels were measured. The expression of p-Akt and p-JNK in adipose tissue of epididymis was detected by Western blotting. F4/80 and Cd11c immunohistochemistry and immunofluorescence staining were performed on the adipose tissue sections. The mRNA expression of cytokines and chemokines in adipose tissue was measured by Real-time fluorescence quantitative PCR. RESULTS: Sesamol treatment reduced body weight and lipid level of obese mice, improved glucose tolerance and insulin resistance. In sesamol treated group, macrophage infiltration in adipose tissue was decreased, p-Akt expression was enhanced, p-JNK expression was reduced, mRNA expression of M1 type of macrophage markers (Cd11c, iNOS, TNF-α and IL-6) was down-regulated, mRNA expression of M2 type markers (chi3l3, Arg1 and Mgl1) was up-regulated. CONCLUSIONS: sesamol could alleviate inflammation and insulin resistance in adipose tissue of obese mice. These effects maybe associated with inhibition of JNK signal pathway and improvement of polarization imbalance of macrophages in adipose tissue.

Key words: sesamol, obese mice, macrophage polarization