Flavone of Hippophae (H-flavone) lowers atherosclerotic risk factors via upregulation of the adipokine C1q/tumor necrosis factor-related protein 6 (CTRP6) in macrophages.

In this study, we examined the mechanism of Flavone of Hippophae (H-flavone) in regulating macrophage foaming and atherosclerosis (AS) plaque formation. H-flavone treatment increased the secretion of C1q/tumor necrosis factor-related proteins 6 (CTRP6) in Ox-LDL-treated mouse peripheral blood macrophage cells (PBMC) and significantly reduced the percentage of cholesteryl ester (CE) in PBMC. Additionally, H-flavone suppressed Ox-LDL-induced cell foaming and the production of inflammatory cytokines through upregulating CTPR6 expression. Next, we further validated the inhibitory effect of H-flavone on plaque formation and inflammation in a mouse AS model. A substantial reduction in the secretion of inflammatory cytokines was observed in apoE^-/- mice by H-flavone. Immunohistochemistry and Oil Red O staining results showed that H-flavone suppressed macrophage infiltration and the development of AS plaque. These effects were more pronounced in early administration. Our results suggest that H-flavone effectively inhibits macrophage foaming, inflammation and vascular plaque formation by upregulating CTRP6 and may be used to reduce AS risk.