Correlation between autophagy and polarization of macrophages in atherosclerosis plaque in arteriosclerosis obliterans amputees / 药学学报

ABSTRACT

This study was designed to investigate the correlation between autophagy and polarization of macrophages in atherosclerosis (AS) plaque in arteriosclerosis obliterans amputees. Femoral artery specimens from arteriosclerosis obliterans amputees were performed hematoxylin and eosin (HE) staining, oil red O and immunofluorescence staining to observe the morphology of atherosclerotic plaque, phenotype of macrophages and autophagy in plaque; using real-time quantitative RT-PCR technology to detect the mRNA level of M1 and M2 type markers in arterial tissue; to analyze polarized signal pathway and autophagy protein levels in macrophages by Western blotting. Arterial specimens staining showed obvious lipid deposition and obvious infiltration of amount of foam cells and inflammatory cells. Macrophages were mainly expression M1 type in percentage in fibrous plaque. Although both M1 and M2 macrophages were upregulated in atheromatous plaque, the increase was dominant in M2 type in percentage. The level of autophagy was significantly higher in the atheromatous plaque than that of fibrous plaque. The expression of tumor necrosis factor- α (TNF-α), monocyte chemotactic protein-1 (MCP-1), inducible nitric oxide synthase (iNOS), interleukin-6 (IL-6) and interleukin-12 (IL-12) mRNA was significantly higher in fibrous plaque than that of atheromatous plaque (P < 0.01 or 0.05), and arginase-1 (Arg-1), transforming growth factor-β (TGF-β), CD163 and interleukin-10 (IL-10) mRNA was significantly lower than that in atheromatous plaque (P < 0.01). The levels of p-STAT1 and NF-κB were significantly increased in fibrous plaque (P < 0.01), while p-STAT6 expression was significantly increased in atheromatous plaque (P < 0.01). The level of LC3-II was significantly higher in atheromatous plaque than that in fibrous plaque (P < 0.01). Macrophages in early atherosclerotic plaque were induced to M1 type through p-STAT1/NF-κB pathway and expressed moderate levels of autophagy; while macrophages in advanced plaques were induced to polarization of M2 type through p-STAT6 pathway. M2 macrophages expressed a higher level of autophagy than M1 macrophages.