Expression of chemokines in macrophage polarization and downregulation of NFκB in aorta allow macrophage polarization by diosgenin in atherosclerosis.

M1 macrophages serve one edge as proinflammatory and M2 macrophages serve the other edge as an anti-inflammatory macrophage. It appears that a related "switch" in macrophage morphology may also happen in the course of atherosclerosis, which has not yet been elucidated. An atherogenic diet (AD) was given to rats, and induction of macrophage differentiation and the nuclear localization of nuclear factor-kappa B (NFκB) were investigated by Western blot and immunofluorescence. Chemokines were analyzed using an antibody array with 32 target proteins. M2 macrophage transformation was confirmed in diosgenin-treated aorta by immunofluorescence and was validated in vitro using THP-1 cells. MAC387 (macrophage marker) and NFκBp65 (inflammatory hub) were upregulated in oxidatively-modified low-density lipoprotein (OxyLDL) and AD-induced condition. Macrophage differentiation, which induced the formation of inflammatory mediators, was not significantly suppressed by the inhibition of NFκB using dexamethasone. M1 macrophage polarization was identified in OxyLDL-induced monocytes, which are proinflammatory in nature, whereas M2 macrophage polarization was noticed in diosgenin-treated monocytes, which exhibit anti-inflammatory properties. M1-and M2-specific chemokines were analyzed using chemokine antibody array. Furthermore, the expression of proinflammatory macrophage (M1) was noticed in AD-induced aorta and anti-inflammatory macrophage (M2) was observed in diosgenin-treated aorta. This is the first report where, unifying the mechanism of diosgenin as aan nti-atherosclerotic and the expression of M1 and M2 specific chemokines is shown by downregulating NFκB and not by preventing the differentiation of monocyte into a macrophage, but by allowing macrophage to differentiate into M2, which aids in preventing the atherosclerotic progression.