While low concentrations of high-density lipoprotein-cholesterol (HDL-C) are widely accepted as an independent cardiovascular risk factor, HDL-C-rising therapies largely failed, suggesting the importance of both HDL functions and individual subspecies. Indeed HDL particles are highly heterogeneous, with small, dense pre-beta-HDLs being considered highly biologically active but remaining poorly studied, largely reflecting difficulties for their purification. We developed an original experimental approach allowing the isolation of sufficient amounts of human pre-beta-HDLs and revealing the specificity of their proteomic and lipidomic profiles and biological activities. Pre-beta-HDLs were enriched in highly poly-unsaturated species of phosphatidic acid and phosphatidylserine, and in an unexpectedly high number of proteins implicated in the inflammatory response, including serum paraoxonase/arylesterase-1, vitronectin and clusterin, as well as in complement regulation and immunity, including haptoglobin-related protein, complement proteins and those of the immunoglobulin class. Interestingly, amongst proteins associated with lipid metabolism, phospholipid transfer protein, cholesteryl ester transfer protein and lecithin:cholesterol acyltransferase were strongly enriched in, or restricted to, pre-beta-HDL. Furthermore, pre-beta-HDL potently mediated cellular cholesterol efflux and displayed strong anti-inflammatory activities. A correlational network analysis between lipidome, proteome and biological activities highlighted 15 individual lipid and protein components of pre-beta-HDL relevant to cardiovascular disease, which may constitute novel diagnostic targets in a pathological context of altered lipoprotein metabolism.

虽然低浓度的高密度脂蛋白胆固醇 (HDL-C) 被广泛认为是一个独立的心血管危险因素，但提高 HDL-C 的治疗基本上失败了，这表明 HDL 功能和个体亚种的重要性。事实上，HDL 颗粒具有高度异质性，小而致密的前 β-HDL 被认为具有高度生物活性，但研究仍很少，这在很大程度上反映了其纯化的困难。我们开发了一种原创的实验方法，可以分离足够量的人类前β-HDL，并揭示其蛋白质组和脂质组谱以及生物活性的特异性。前β-HDL富含高度多不饱和的磷脂酸和磷脂酰丝氨酸，以及与炎症反应有关的大量蛋白质，包括血清对氧磷酶/芳基酯酶-1、玻连蛋白和簇蛋白，以及补体调节和免疫，包括触珠蛋白相关蛋白、补体蛋白和免疫球蛋白类蛋白。有趣的是，在与脂质代谢相关的蛋白质中，磷脂转移蛋白、胆固醇酯转移蛋白和卵磷脂：胆固醇酰基转移酶在前β-HDL中高度富集或仅限于前β-HDL。此外，前β-HDL 有效介导细胞胆固醇流出并表现出强大的抗炎活性。脂质组、蛋白质组和生物活性之间的相关网络分析强调了与心血管疾病相关的 15 种前 β-HDL 脂质和蛋白质成分，这些成分可能在脂蛋白代谢改变的病理背景下构成新的诊断靶点。