Objective:To investigate the induction effect of different concentrations of glucose on the polarization of Raw264.7 macrophages in vitro.Methods:The Raw264.7 cells cultured in DMEM medium were divided into control group(5.5 mmol·L-1 glucose),different high-glucose groups(15.0,25.0,35.0,and 45.0 mmol·L-1 glucose),and positive control group[lipopolysaccharide(LPS)].The cells were cultured for 3,6,and 9 h,respectively.Cell morphology was observed in various groups.Cell counting kit-8(CCK-8)method was used to assess the survival rates of cells in various groups.Real-time fluorescence quantitative PCR(RT-qPCR)method was used to detect the expression levels of interleukin-6(IL-6),tumor necrosis factor-α(TNF-α),and interleukin-10(IL-10)mRNA in cells in various groups.Enzyme-linked immunosorbent assay(ELISA)was used to measure the levels of IL-6,TNF-α,and IL-10 in the cell supernatants in various groups.Flow cytometry was used to determine the percentages of M1 and M2 macrophage markers,CD86+and CD163+cells,in various groups.Results:In control group,theRaw264.7 cells adhered to the culture dish,with a predominantly round morphology.The cells in 35.0 mmol·L-1 high-glucose group and positive control group showed elongated shapes and pseudopodium formation,indicating inflammatory changes.Compared with control group,the survival rates in different high-glucose groups at 6,12,24,and 48 h after treatment were increased(P＜0.05).Compared with control group,after 3 h of treatment,the expression levels of IL-6 and IL-10 mRNA in the cells in 35.0 mmol·L-1 high-glucose group were increased(P＜0.05 or P＜0.01),while no significant changes were observed in IL-6,TNF-α,and IL-10 levels in the cell supernatants(P＞0.05);after 6 h of treatment,the expression level of TNF-α mRNA in the cells in 35.0 mmol·L-1 high-glucose group was increased(P＜0.001),and the levels of IL-6,TNF-α,and IL-10 in the cell supernatants were significantly increased(P＜0.05 or P＜0.001);after 3 h of treatment,the percentages of macrophage markers CD86+cells and CD163+cells in 35.0 mmolL-1 high-glucose group were significantly increased(P＜0.01 or P＜0.001).Conclusion:A certain high concentration of glucose may induce the polarization of Raw264.7 macrophages towards the M1 subtype in vitro.