载脂蛋白M与脂蛋白的代谢及其调节

The metabolism regulation of apolipoprotein M and lipoprotein

载脂蛋白M(apoM)是lipocalin家族成员,其表达具有组织特异性。血小板活化因子(PAF)能增加apoM以及apoM mRNA在Hepg2细胞中的表达,而PAF受体拮抗剂(lexipafant)能抑制apoM的表达。apoM血清水平的高低与肝细胞核因子(HNF-1a)浓度有关,胰岛素在体内也调节apoM的生成。瘦素(Leptin)特异性调节apoM的分泌。apoM大部分存在于高密度脂蛋白(HDL)中,影响HDL的代谢并具有抗动脉粥样硬化作用。通过对apoA-I缺陷小鼠研究发现:正常小鼠体内apoM与apoA-I代谢有关。在低密度脂蛋白(LDL)与HDL中apoM存在5个亚型。在汉族人群中apoM基因的核苷酸778C等位基因以及855C均能增加患冠状动脉粥样硬化的危险性。apoM似乎与2型糖尿病患者的动脉粥样硬化的因子相关。

Apolipoprotein M which belongs to lipocalin protein Super-family expresses in specific tissue. Platelet-Activating Facfor （PAF） can enhance the apoM mRNA levels and the secretion ofapoM in HepG2 cell cultures. Furthermore, Lexipafant, a PAF-receptor antagonist, restrains the mRNA levels and the secretion of apoM in HepG2. The plasma level of apom is associated with hepato- cyte nuclear factor-1a（HNF-1a） concentration. Insuline also regulates apoM levels in vivo. Leptin has a specific regulatory effect on hepat- ic apoM transcription and secretion. ApoM is mainly associated with high-density lipoprotein in human plasma. It affects HDL metabolism and has fi,mction of anti-atherogenesis. We found that： apoM was associated with apoA-I metabolism in wild-type mice when we studied apoA-I deficient mice. ApoM has five subclasses in low-density lipoprotein and HDL. In Chinese population, C allele at nucleatide-778 and 885 in the apoM gene are risk factors for coronary artery disease. In 2 diabetes patients it seems to correlate with atherosclerosis factors.