Anti-inflammatory Mechanisms of Icariin in THP-1 Monocytes: Regulation of Phagocytosis, Chemotaxis and Polarization

Objective To investigate the regulatory effects of icariin (ICA) on lipopolysaccharide (LPS)-induced inflammatory response in THP-1 human monocytic cell line and its underlying mechanisms.Methods The safe concentration of ICA (10⁻⁶ mol/L) was determined by CCK-8 assay. The effects of ICA on phagocytic function (fluorescent latex beads), CCR2 chemokine receptor expression, and macrophage polarization markers (CD86/CD206) were evaluated by flow cytometry. qPCR was used to analyze mRNA expression levels of pro-inflammatory cytokines (IL-6、IL-1 and TNF-α).Results Compared with the LPS-induced group, ICA significantly enhanced the phagocytic capacity of THP-1 cells (p<0.05), suppressed LPS-induced upregulation of CCR2 expression (p<0.01), reduced M1 macrophage polarization (decreased proportion of CD86+ macrophages), and decreased gene expression of IL-6、IL-1 and TNF-α (p<0.01).Conclusion ICA exerts anti-inflammatory effects by modulating monocyte phagocytosis, chemotaxis, and macrophage polarization, providing experimental evidence for the treatment of inflammatory diseases.