Serum amyloid A protein enhances the activity of secretory non-pancreatic phospholipase A2.
Serum amyloid A protein enhances the activity of secretory non-pancreatic phospholipase A2.
复制标题
血清淀粉样蛋白 A 增强分泌型非胰腺磷脂酶 A2 的活性。
DOI：
10.1042/bj3090461
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Vadas,P
中科院分区：
文献类型：
--
作者：
Pruzanski,W;deBeer,FC;deBeer,MC;Stefanski,E;Vadas,P
急性时相蛋白血清淀粉样蛋白A蛋白（SAA）和分泌型磷脂酶A2（sPLA 2）在炎症条件下同时表达。SAA与高密度脂蛋白（HDL）相关，改变其理化组成。我们发现，纯化的急性期SAA，但不是组成型的形式，显着增强了以剂量相关的方式与磷脂酰胆碱/溶血磷脂酰胆碱或磷脂酰乙醇胺/溶血磷脂酰乙醇胺脂质体底物的sPLA 2的脂解活性。发现正常HDL以剂量依赖性方式降低sPLA 2活性，但当检测含有27%SAA的急性期HDL时，其增强sPLA 2活性。免疫纯化的抗SAA单特异性抗体完全取消SAA和急性期HDL的增强活性。鉴于HDL在脂蛋白代谢中的中心作用，HDL、SAA和sPLA 2之间的相互作用可能是急性期脂蛋白代谢中检测到的变化的原因。
The acute-phase proteins serum amyloid A protein (SAA) and secretory phospholipase A2 (sPLA2) are simultaneously expressed during inflammatory conditions. SAA associates with high-density lipoprotein (HDL) altering its physicochemical composition. We found that purified acute-phase SAA, but not the constitutive form, markedly enhances the lipolytic activity of sPLA2 in a dose-related manner with phosphatidylcholine/lysophosphatidylcholine or phosphatidylethanolamine/lysophosphatidylethanolamine liposomal substrates. Normal HDL was found to reduce activity of sPLA2 in a dose-dependent manner, but when acute-phase HDL containing 27% SAA was tested, it enhanced sPLA2 activity. Immunopurified monospecific antibodies against SAA completely abolished the enhancing activity of SAA and acute-phase HDL. Given the central role of HDL in lipoprotein metabolism, the interaction between HDL, SAA and sPLA2 may account for changes detected in lipoprotein metabolism during the acute phase.