肥大细胞在动脉粥样硬化斑块形成和破裂中的意义

肥大细胞,作为炎症细胞参与了人类动脉粥样硬化病变的早期和后期机制。体外研究表明,活化的即有免疫学活性的肥大细胞既可以水解低密度脂蛋白3使胆固醇在细胞内积累,又可以水解高密度脂蛋白使细胞内胆固醇流出减少,从而促进巨噬细胞和平滑肌细胞转成泡沫细胞;它能够激活基质金属蛋白酶、降解细胞外基质,还能抑制平滑肌细胞增生、诱导平滑肌细胞凋亡、抑制胶原合成和促进新血管形成而使斑块倾向破裂。以上这些作用使它在斑块形成和斑块破裂中起着重要作用。

Role of Mast Cell in Formation and Rupture of Atherosclerotic Plaque

Mast cells,an inflammatory cell type,play an important role in early and late stages of human atherosclerotic lesions.The vitro studies suggested that mast cells activated not only proteolyze low-density lipoproteins,which accelerates cellular cholesterol accumulation,but also proteolyze high-density lipoproteins,which prevents cellular efflux of cholesterol.Thus,these mast cells promote the conversion of both macrophages and smooth muscle cells into foam cells.In addition,mast cells can trigger destabilization of the plaque by activating matrix metalloproteinase,facilitating extracellular matrix degradation,inhibiting smooth muscle cells proliferation and inducing them apoptosis,inhibiting collagen synthesis,and by accelerating neovascularization.These findings above suggested that mast cells play a significant role in both formation and rupture of atherosclerotic plaques.