Electroacupuncture facilitates M2 macrophage polarization and its potential role in the regulation of inflammatory response.

The underlying mechanism of electroacupuncture (EA) in relieving obesity, anti-inflammation and the interaction with metabolic pathways in obese mice has not been elaborated. The aim of this study was to investigate the regulation of EA on macrophage polarization in obesity tissue of diet-induced obesity mice. Mice were divided in 6 groups: normal control group, model group, EA-7 group, EA-14 group, EA-21 group and EA-28 group. Low-frequency EA was applied at "Tianshu (ST 25)", "Guanyuan (CV 4)", "Zusanli (ST 36)" and "Sanyinjiao (SP 6)" for 10 min. Adipose tissue was assessed with hematoxylin and eosin staining. Adipocytokines and pro-inflammatory factors expression was measured by ELISA. The protein and mRNA levels of macrophage markers were examined by immumohistochemical staining and RT-PCR, respectively. EA treatment was associated with a decrease of adipose tissue and large adipocytes, and an increase of small adipocytes. After EA treatment, the levels of Leptin, Chemerin, TNF-α, F4/80, iNOS, and CD11c decreased obviously in adipose tissue, while IL-4, IL-10 and CD206 levels increased significantly. Besides, TNF-α in spleen tissue was also downregulated, but IL-4 and IL-10 were upregulated. EA prevents weight gain through modulation inflammatory response and macrophage polarization in obese adipose tissues.