Serum And Monocyte-derived-macrophages Expression Of Adipocyte Fatty Acid Binding Proteins In Patients With Coronary Artery Disease

Objectives To measure the serum adipocyte fatty acid binding protein (A-FABP) levels in patients with and. without coronary artery disease (CAD), trying to investigate the relationship between serum A-FABP and CAD. To compare secretion of A-FABP in cultured human monocyte-derived -macrophages from subjects with and without CAD in vitro.Methods Three hundred and forty subjects underwent coronary angiography(CAG) were classified into CAD group(n=211) and non-CAD group (n=129) according to the CAG result. Serum A-FABP and adiponectin levels were determined by enzyme-linked immuneosorbent assays. The severity of coronary artery stenosis was assessed by the numbers of involved coronary artery branches and the sum of the Gensini scores. Among them, 10 CAD patients and 10 age-, sex-, and BMI-matched controls were selected for in vitro measurement of A-FABP in cultured monocyte-derived macrophages. Briefly, peripheral blood monocytes were obtained by centrifligation using Ficoll density gradient and plate adherency. After 48 hours of stimulation into macrophages with 80ng/ml PMA, the cell culture supernatant was collected and the concentration of A-FABP and adiponectin levels were assayed by enzyme-linked immunosorbent assays.Results The levels of serum A-FABP were significantly higher in patients with three vessel lesions [18.6 (13.8-24.0) ng/ml] than those with single vessel lesion [17.5(13.5-20.3)ng/ml, p<0.05] and those with non-lesions [16.4(13.5-20.4) ng/ml, p<0.05]. CAD patients tend to have higher A-FABP levels [18.3(13.2-22.8) ng/ml] than non-CAD subjects [16.4(13.5-20.4) ng/ml], but the difference did not reach statistical significance(P=0.088). Women had higher serum A-FABP level than men [20.0 (16.9-23.9) vs. 15.4 (12.5-20.3 ) ng/ml, p<0.05] and the difference in A-FABP were statistical significant between CAD patients and controls in females[22.8 (15.6-22.7) ng/ml vs. 18.1(15.6-21.8) ng/ml]. Serum A-FABP levels were positively correlated with Gensini scores in both men (r=0.105, P<0.05) and women (r=0.405,P<0.01). Multiple linear regression analysis showed that serum A-FABP level was independently associated with Gensini scores in women (P=0.018), but not in man. When A-FABP/adiponectin ratio was used, the difference was more prominent than A-FABP alone between subjects with CAD and subjects without CAD[(1.51±0.79) vs. (0.89±0.30) ng/μg, P<0.01], suggesting the ratio a better marker for CAD risk. Monocyte-derived-macrophages from patients with CAD had higher A-FABP/adiponectin ratio compared to that from patients without CAD.Conclusions1. The levels of serum A-FABP levels was significantly higher in patients with three vessel lesions than those with single vessel lesions and non-vessel lesion, indicating the correlation between A-FABP and extent of coronary artery atherosclerosis .2. Serum A-FABP is associated with CAD more closely in females than in males.3. A-FABP/adiponectin ratio may be a better predictor for CAD risk than A-FABP alone.