Figure 3. Effects of celastrol on the expression of macrophage M1 and M2 biomarkers in RAW264.7 cells. (A) Cytotoxicity of celastrol. Following 48 h treatment, RAW264.7 cells were determined for the cell viability by a colorimetric MTT assay relative to the untreated controls (n = 3). **, p < 0.01 (Celastrol vs Control). (B) Effects of celastrol on the expression of iNOS, COX-2 and arginase-1 in LPS-stimulated RAW264.7 cells. After 24 h treatment with LPS and/or celastrol, the cellular proteins were analyzed by Western blotting with specific antibodies and GAPDH (as loading control). The blots (n = 3) were quantified by a densitometric method. Representative blots were shown. (C) qRT-PCR quantification of macrophage M1 and M2 biomarkers in RAW264.7 cells. After treatment with LPS and/or celastrol, the mRNA levels of specific biomarkers (n = 3) were analyzed by qRT-PCR technique using Qiagen primers. C0.25, celastrol (0.25 μM); C0.5, celastrol (0.5 μM); C0.75, celastrol (0.75 μM); *, p < 0.05; **, p < 0.01; ***, p < 0.001.