The Research On Apolipoprotein M Levels Relating To The Severity Of Coronary Artery Lesions, Leptin And Lipids Of Coronary Heart Disease Patients

BackgroundApolipoprotein M (apoM), a member of lipocalin super-family, is arecently discovered apolipoprotein. It is associated mainly with high-density lipoprotein (HDL) in plasma and is also present in triglyceride-rich lipoprotein and low-density lipoprotein (LDL). It was observed in animal experiments that mice with apoM deficiency showed impaired pre(3-HDL formation and abnormally large particulate HDL appearance; and further adenovirus mediated over expression in the liver of apoM in LDL-recepter knock-out mice protected against atherosclerosis. The results showed that apoM may regulate the metabolism of HDL and may have protective effect on atherosclerosis. Up to now, the physiological function of apoM and the relationship between apoM and antiatherosclerosis diseases are still unknown, although apoM cDNA has been cloned and sequenced in 1999. Untill now, there is no report on the research of apoM and the degree of different atherosclerotic lesions.ObjectiveThe aim of the study is to investigate serum apoM levels relating to coronary atherosclerotic lesions, Leptin and lipids; and further to reveal the physiologic function and regulatory factors of apoM and the clinical significance of its concentration in coronary heart disease patients serum .Methods Seventy-three patients with coronary heart disease (CHD group) and fourty-seven subjects without CHD (control group) confirmed by coronary angiography were studied. The patients with CHD were divided into two groups, including acute coronary syndrome(ACS) group and stable angina(SA) group according different clinic type of coronary heart disease; evaluate the extent of coronary atherosclerotic lesion according to the number of diseased coronary artery, the severity of coronary stenosis estimated by Gensini scores and the category of coronary artery lesion of type A lesion, type B lesion and type C lesion by ACC/AHA(The American College of Cardiology/American Heart Association). The serum apoM and Leptin levels were measured by enzyme linked immunosorbent assay (ELISA); and the serum apoM levels of different clinic types and different coronary atherosclerotic lesion extent were compared; then the correlations of serum apoM levels with serum Leptin, Triglyceride (TG), High density lipoprotein cholesterol (HDL-C), Low density lipoprotein cholesterol (LDL-C), total cholesterol (TC), apolipoprotein AI (apoAI), lipoprotein (a)[ LP (a)], free fatty acid(FFA) and apolipoprotein B (apoB )levels were analyzed respectively.Results1. Compared to controls, the serum levels of apoM were significantly lower in CHD group ; while the serum levels of Leptin were significantly higher in CHD group .the difference had statistical significance (both P<0. 01).2. The serum levels of apoM were significantly lower in ACS group than in SA group and controls, and the difference had statistical significance (both P< 0.05).3. The serum levels of apoM in CHD group correlated with the number of diseased coronary artery, the severity of coronary stenosis and the category of coronary artery lesion. Serum apoM levels in multiple-branch lesions group were significantly lower than in single-branch lesion group and in two-branch lesion group(both P <0. 05); Serum apoM levels in midrange narrow group were significantly lower than in the gently narrow group(P < 0. 05); the serum levels of apoM in the serious narrow group were both lower than in gently and midrange narrow groups(both P < 0. 05); the serum levels of apoM in type C lesion group were both lower than in type A and type B lesion groups (both P < 0. 05).4. The serum levels of apoM negatively correlated with the number of diseased coronary artery, the category of coronary artery lesion and Gensini scores (all the P < 0. 01), and the serum levels of apoM positively correlated with Leptin,HDL-C (both P < 0. 01), meanwhile negatively correlated with LDL-C , LP (a)and FFA (all the P < 0. 05). Multiple linear stepwise regression analysis showed that serum apoM levels correlated with serum Leptin levels most closely. Conclusion1.The serum levels of apoM in coronary atherosclerosis patients and acute coronary syndrome patients are significantly lower and the extent of coronary atherosclerotic lesion is more serious, the serum levels of apoM are also more lower, It is indicated that the serum levels of apoM may correlated with the extent of coronary atherosclerotic lesion and plaque stability.2.the serum levels of apoM positively correlated with HDL-C, meanwhile negatively correlated with LDL-C, LP (a)and FFA. It is indicated that the levels of apoM may take part in the lipid metabolism and have protective effect in atherosclerosis.3. the serum levels of apoM positively correlate with Leptin, It is indicated that Leptin may be a regulatory factor of apoM.