Anti-inflammatory and polarization-modulating effects of Houttuynia cordata in LPS-stimulated RAW264.7 macrophages

Compared with LPS alone, HC treatment before LPS stimulation significantly reduced IL-1β, TNF-α, nuclear NF-κB, and pERK levels while increasing TGF-β levels. Compared with HC pretreatment, HC treatment after LPS stimulation further decreased the IL-6, TNF-α, nuclear NF-κB, and pERK levels. LPS resulted in a trend toward increased CD80 expression in macrophages. Both HC pretreatment and HC posttreatment tended to increase CD163 expression in macrophages. Our study demonstrated that HC, particularly when administered after inflammation onset, effectively reduces proinflammatory cytokine levels, modulates key signaling pathways, and polarizes macrophages toward an anti-inflammatory phenotype. These effects suggest that HC has significant therapeutic potential in treating inflammatory diseases by modulating macrophage activity.