High glucose induced macrophages polarized into M2 via activation of PI3K/Akt signaling pathway

Objective To study the mechanism of differentiation of high glucose induced M2 macrophages used by high glucose medium stimulation. Methods Raw264.7 (murine macrophage cell line)was cultured and stimulated by 4.25% glucose medium, and mannitol medium was used as osmotic pressure control. Cells were harvested at 0h, 4h, 8h and 12h to examine the expression of CD206 and Arg-1 and the activation of PI3K/Akt signaling pathway. After blocking the PI3K/Akt signaling pathway by LY294002 (the specific inhibitor of PI3K), the expression of Arg-1 was examined by western blot. Results The expression of Arg-1 was increased from 8h while CD206 reached the peak at 12h induced by high glucose which indicated the activation of M2 in a time-dependent manner. Akt was phosphorylated at 8h stimulated by high glucose medium. The specific inhibitor of PI3K reduced the expression of Arg-1 by blocking the phosphorylation of Akt. Conclusion High glucose, rather than high osmotic pressure, induced macrophages polarized into M2 via activation of PI3K/Akt signaling pathway. (Chin J Endocrinol Metab, 2017, 33: 976-981) Key words: High glucose; PI3K/Akt signaling pathway; Macrophage