M2 macrophage immunotherapy abolishes glucose intolerance by increasing IL-10 expression and AKT activation.

Aim: Glucose intolerance associates with M1/M2 macrophage unbalance. We thus wanted to examine the effect of M2 macrophage administration on mouse model of glucose intolerance. Materials & methods: C57BL/6 mice fed a high-fat diet (HFD) for 12 weeks and then received thrice 20 mg/kg streptozotocin (HFD-GI). Bone marrow-derived stem cells were collected from donor mice and differentiated/activated into M2 macrophages for intraperitoneal administration into HFD-GI mice. Results: M2 macrophage treatment abolished glucose intolerance independently of obesity. M2 macrophage administration increased IL-10 in visceral adipose tissue and serum, but showed no effect on serum insulin. While nitric oxide synthase-2 and arginase-1 remained unaltered, M2 macrophage treatment restored AKT phosphorylation in visceral adipose tissue. Conclusion: M2 macrophage treatment abolishes glucose intolerance by increasing IL-10 and phosphorylated AKT.