The Correlation Of Serum Angiopoietin-like Protein 4 Level With Severity Of Coronary Artery Lesions

Coronary atherosclerotic heart disease refers to that the stenosis or occlusion of coronary caused by atherosclerosis leads to myocardial ischemia and hypoxia or necrosis, which is called coronary heart disease for short. Coronary heart disease is the most common type of organ disease caused by atherosclerosis. Monocytes move into the arterial intima, translating into foam cells after lipid phagocytosis, thereby forming lipids point, which is the characteristic of early atherosclerotic plaque. Angiopoietin-like protein 4(Angptl4) is an endogenous inhibitor of the triglyceride-hydrolyzing enzyme lipoprotein lipase(LPL) which catalyzes uptake of circulating lipids into tissues. Angptl4 irreversibly inhibits LPL activity by converting active LPL dimers into inactive monomers. Consequently, overexpression of Angptl4 reduced fatty acid uptake in tissues. Thus, Angptl4 suppresses foam cell formation to reduce atherosclerosis development.Objective:In this study,we measured the serum level of Angptl 4 and evaluate the severity of coronary artery lesion through SYNTAX score according to the result of coronary angiography. We aimed to investigate the correlation of serum angiopoietin-like protein 4 level with severity of coronary artery lesion, thus, providing new theoretical basis for clinical condition assessment and prevention.Method:1 According to the Chinese Society of Cardiology 2007 revision of CHD diagnosis and treatment guidelines,we consecutively collected 118 patients who underwent the coronary angiography afterwards admitted to the cardiovascular department of Second Affiliated Hospital of He Bei Medical University from July 2015 to Dec 2015. Patients with the following diseases were included:preliminary admission diagnosis was coronary heart disease and coronary angiography was taken afterwards. Patients with the following diseases were excluded: a previous history of old myocardial infarction or percutaneous coronary intervention or coronary artery bypass graft surgery, other types of cardiovascular disease such as valvular heart disease, cardiomyopathy,myocarditis,cardiac dysfunction and so on, dysfunction of liver and kidney, acute and chronic inflammatory or infectious diseases, hypothyroidism or hyperthyroidism,malignant tumor,disease of the immune system,blood system diseases,the recent history of surgery or trauma,diabetes. The subjects were clarified by results of coronary angiography and clinical performance into two groups, including control group with no obvious coronary stenosis and coronary artery disease(CHD) group with significant coronary stenosis defined as ?50% luminal diameter stenosis of at least one of main coronary artery containing left main stem, left anterior descending, left circumflex, right coronary. The CHD group was divided into two groups: acute coronary disease(ACS) group, and stable angina pectoris(SAP) group. Simultaneously, we calculated the SYNTAX score according to the results of coronary angiography. CHD group could be divided into low risk group(0~22 points), moderate risk group(23~32 points), high risk(33 points or higher).2 We took a detailed record of the subjects including gender, age, previous history, familial history, smoking history, height, weight and so on.Blood samples were taken in the early morning(fasting 8 hours at least). Brachial vein blood(5ml) was extracted to tubes, centrifuged at 2000r/min 10 mins. The separation of the upper serum after being confirmed with no hemolysis were saved to-80? refrigerator to measure Angptl4 level. Triglyceride, cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, hypersensitive c-reactive protein, fasting plasma glucose were determined at the same time.Using ELISA method to determine the level of Angptl4.Operation steps were peformanced strictly by the introduction.3 All data were analyzed by SPSS 22.0 softwate. Measurement with normal distribution was expressed as mean ± standard deviation. T test was used to compare between two groups.One way analysis of variance was used to compare with multiple groups. Enumeration data were expressed by percentage and compared with ?~2 test. P<0.05 was considered statistically significant.Results:1 Comparion of general data and clinical indicatorsThe study included 118 patiens among which 31 cases were in control group and 87 in CHD group. Among the CHD group, there were 32 cases belonging to the SAP group and 55 cases belonging to the ACS group. There was no statistically significant difference(P>0.05) among the CON group and CHD group in age(58.65±9.15 year vs 57.28±9.85year), gender(M:F 17:14 vs 50:37), hypertion(51.6% vs 51.7%), smoking history(22.5% vs 27.5%), TG(1.45±1.04mmol/L vs 1.44±1.21mmol/L, CHOL(4.14±0.92mmol/L vs 4.18±0.56mmol/L), FPG(5.19±0.78mmol/L vs 5.20±0.27mmol/L). BMI(24.32±2.82kg/? vs 23.66±3.78kg/?), hs-CRP(5.55±2.07mg/L vs 2.53±1.14 mg/L), LDL-C(2.76±0.54mmol/L vs 2.50±0.81mmol/L)were significantly higher in the CHD group than the CON group(P<0.05). HDL-C(1.26±0.29 mmol/L vs 1.02±0.17,P<0.05)was significantly higher in the CON group than the CHD group.Hs-CRP(5.97±1.93mg/L vs 4.83±2.14mg/L,P<0.05), LDL-C(2.87±0.51mmol/L vs 2.68±0.38mmol/L)were significantly higher in the ACS group than the SAP group.2 Comparion of Angptl4 level among groupsThe level of Angptl4 was significantly higher in CON group than CHD group(41.61±5.80ng/ml vs 21.08±4.91 ng/ml,P<0.05). Angptl4 level in CON group was significantly higher than SAP group(41.61±5.80ng/ml vs 30.84±4.54ng/ml, P<0.05) and ACS group(41.61±5.80ng/ml vs 17.43±5.39ng/ml, P<0.05). The level of Angptl4 was significantly higher in SAP group than CHD group(30.84±4.54 ng/ml vs 17.43±5.39ng/ml,P<0.05).3 Correlation between the level of Angptl4 and risk factorsAmong all the subjects, the level of serum Angptl4 was negatively correlated with BMI(r=-0.155,P<0.05). Among CHD group, the level of serum Angptl4 was negatively correlated with hs-CRP(r=-0.513,P<0.05) and LDL-C(r=-0.249,P<0.05), and positively related with HDL-C(r=0.435, P<0.05).4 Correlation between the level of Angptl4 and SYNTAX scoreIn CHD group, the level of Angptl4 was negatively correlated with SYNTAX score(r=-0.877,P<0.05). The Angptl4 level in low risk group was higher than moderate risk group(30.94±3.43ng/ml vs 20.94±2.78ng/ml)and high risk group(30.94±3.43ng/ml vs 12.44±2.78ng/ml). The Angptl4 level was higher in moderate group than high risk group(20.94±2.78ng/ml vs 12.44±2.78ng/ml).5 We regarded SYNTAX score which represent the severity of coronary artery lesion as dependent variable, while the age, gender, BMI, hypertension, smoking history, FPG, TG, CHOL, LDL-C, HDL-C, hs-CRP, Angptl4 as the independent variables, carrying on multipe linear regression analysis. The results showed that serum CHOL?LDL-C?Angptl4 had linear regression relation SYNTAX score,and they are independent factors excludeing age, gender, BMI and other factors.Conclusions:The level of Angptl4 in CHD group was significantly reduced and negatively correlated with SYNTAX score. Angptl4 level may be a prediction of the severity of coronary lesion, providing a new research direction for prevention and treatment of coronary heart disease.