高密度脂蛋白的抗氧化与抗炎症作用
南华大学心血管病研究所
姜志胜
HDL的产生及成熟过程
HDL的血管内修饰及其清除途径
HDL除具有胆固醇逆向转运作用外，近来研究发现，它还具有抗氧化和抗炎症作用
体内活性氧的来源：
线粒体呼吸链代谢
NADPH氧化酶
NOS
环氧化酶
脂氧化酶
细胞色素P450单加氧酶
黄嘌呤氧化酶
活性氧促发AS：损伤血管壁，导致脂质沉积；氧化LDL，促进泡沫细胞的形成，等等。
研究发现，HDL是体内血浆脂质过氧化物的主要转运载体。
HDL能转运清除脂质过氧化物的酶类，包括：
对氧磷酶-1 (paraoxonase-1 )
对氧磷酶-3 (paraoxonase-3 )
谷胱甘肽磷脂过氧化物酶 (glutathione phospholipid peroxidase)
HDL还能运输清除氧化磷脂的酶类，如血小板活化因子酰基水解酶(platelet-activating factor acely hydrolase),卵磷脂胆固醇酯酰基转移酶( lecithin cholesterol ester acyltransferase)。等等。
HDL是脂质过氧化物的主要载体
Inhibition of LDL-oxidation in vitro by HDL and PON1
ox-LDL (100 ?g/ml) was incubated with 10 ?mol Cu2+ for 4 h at 37?C. Lipoprotein concentration was 100 ?g/ml, pPON1 and rPON1 were 20U of paraoxon hydrolysed per ml (n=3). Significantly different from ox-LDL: *P < 0:001. h, human; os, ostrich; p, purified; and r, recombinant.
Mackness B, et al. Biochemical and Biophysical Research Communications,2004, 318: 680–683
HDL显著拮抗LDL的氧化
LDL was incubated at 37?C for 3 or 6 hours with addition of buffer (stippled bars), wild-type C57BL/6J HDL (open bars), or PON1 Tg HDL in the presence of copper to induce oxidation.
Tward et al, Circulation,2002,106:484-490
HDL显著拮抗LDL的氧化
LDL was incubated at 37?C for 3 or 6 hours with addition of buffer (stippled bars), apoE KO HDL (open bars), or PON1 Tg/apoE KO HDL in the presence of copper to induce oxidation.
Tward et al, Circulation,2002,106:484-490
近来研究发现，HDL具有明显的抗炎症作用：
抑制Ox-LDL诱导的单核细胞迁移：与paraoxonase和PAF酰基水解酶对HDL的作用有关。冠心病及非冠心病患者的HDL对单核细胞趋化作用的抑制程度不同。
抑制活化的内皮细胞表面粘附分子的表达：以剂量依赖性方式抑制细胞因子诱导的HUVECs 血管细胞粘附分子-1(VCAM-1)、细胞间粘附分子-1(ICAM-1) 和E-选择素(E-selectin)的表达。
来自不同个体的HDL对细胞因子表达的抑制活性各不相同。
HDL对细胞因子表达的抑制作用不受HDL 颗粒大小或载脂蛋白、胆固醇酯、甘油三酯成分差异的影响，但与磷脂成分密切相关。含亚麻酰磷脂酰胆碱(linoleoyl-phosphatidylcholine,PLPC)和花生四烯酰磷脂酰胆碱(arachiclonyl-phosphatidylcholine, PAPC)的rHDL对VCAM-1表达的抑制分别为95℅和70℅；而含油酰磷脂酰胆碱(oleoyl-phosphatidylcholine,POAC)的rHDL的抑制率为16℅，含棕榈酰磷脂酰胆碱(palmitoyl-phosphatidylcholine,DPPC)的rHDL则无抑制活性。
不同个体来源的HDL对细胞因子诱导的内皮细胞VCAM-1表达的抑制作用
HUVECs were pre-incubated for 1 hour with HDLs isolated from each of 6 subjects before being activated with TNF-? and incubated for a further 4.5 hours. C, A control incubation in which TNF- ? was not added.
HDL抑制CRP诱导的E-selectin表达
HUVECs were stimulated with CRP (10 g/mL) for 5 hours after preincubation for 16 hours with varying concentrations of native HDL. *P<0.05, **P<0.01, compared with CRP group. Wadham, et al.Circulation. 2004,109:2116-2122
HDL抑制CRP诱导的粘附分子mRNA表达
HUVECs were stimulated with CRP (10 ?g/mL) for 5 hours after preincubation for 16 hours with varying concentrations of native HDL. *P<0.05, **P<0.01, compared with CRP group. Wadham, et al.Circulation. 2004,109:2116-2122
HDL和PON1抑制Ox-LDL刺激的MCP-1的分泌
All lipoproteins were added at a concentration of 100?g/ml culture medium. Purified and recombinant PON1 were added at 20U of paraoxon hydrelysis. Significantly different from control *P<0.001. Significantly different from Ox-LDL:+P<0.01;++P<0.001. n, normal. os,ostrich
Mackness B, et al. Biochemical and Biophysical Research Communications,2004, 318: 680–683
伴高水平HDL-胆固醇的冠心病患者HDL炎症指数的改变
The HDL inflammatory index was determined in human artery wall cell cocultures and in the cell-free assay.
辛伐他汀对冠心病病人HDL炎症指数的影响
The data shown are for patients before and after simvastatin treatment (40mg/day for 6 weeks) and for healthy age- and gender-matched controls. A, in human artery wall cell cocultures, and B in a cell-free assay.
HDL通过抑制Sph Kinase 阻止细胞因子诱导的内皮细胞粘附分子的表达
SM-ase, sphingomyelinase神经鞘磷脂酶; Sph Kinase, sphingosine kinase; NF- ?B, nuclear factor ?B; Sph-1-P, sphingosine-1-phosphate
HDL的逆向胆固醇转运、抗氧化、抗炎症作用以及与AS的关系
HDL抗氧化/抗炎特性的(潜在)临床意义
HDL的抗氧化作用可保护血管壁的功能，拮抗LDL的氧化，阻止AS病变的形成
AS为一炎性疾病，HDL抗炎特性有助于抗AS
动物实验表明，apo A-I或其类似物，D-4F，能降低脂蛋白的氧化和增加胆固醇逆向转运，阻止AS的形成和发展，具有临床应用前景
HDL的抗炎特性在甄别CHD方面优于HDL胆固醇？
HDL抗氧化/抗炎作用的研究展望
进一步阐明HDL抗氧化/抗炎作用的方式、途径及其机制，包括涉及到的细胞内信号转导通路
进一步探索HDL抗氧化/抗炎活性大小在甄别AS发生发展及严重程度中的价值
进一步观察HDL的抗氧化/抗炎活性对AS形成与发展的作用程度
进一步研究利用HDL抗氧化/抗炎活性防治AS的新策略，寻找新途径
谢 谢