Evaluation of soluble lectin-like oxidized low-density lipoprotein receptor-1 (sLOX-1) and sLOX-1/oxidized LDL ratio as novel biomarkers of acute coronary syndrome.

The lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is involved in the pathophysiology of atherosclerosis and acute coronary syndromes (ACS). In patients with acute coronary syndrome, circulating soluble LOX-1 (sLOX-1) levels are dramatically elevated. This study aimed to assess sLOX-1 levels in acute coronary syndromes and determine the ratio of sLOX-1 and oxidative LDL in cases of myocardial infarction and unstable angina pectoris and the ROC curve for this ratio sLOX-1. A case-control study was conducted at the department of chemistry and biochemistry, college of medicine, Al- Nahrain University, Baghdad, Iraq, from September 2020 to January 2021. In a total of 90 subjects (30 patients with myocardial infarction within the first six hours of chest pains, 30 patients with unstable angina pectoris, and 30 healthy donors). The ELISA technique measured concentrations of sLOX-1 and oxidized LDL. In addition, Troponin and highly sensitive C reactive protein were measured by the same technique (Fluorescence immune assay), and lipid profile was measured using the Spectrophotometer technique. The median level of sLOX-1 in MI group was 476.17 pg/ml (90.88-675.4 pg/ml) which was significantly higher than that of UA patients (median=289.1 pg/ml [62.74-585.43 pg/ml]) and controls (median=144.52 pg/ml [79.17-283.83 pg/ml]) with highly significant differences and the median sLOX-1/OX-LDL ratio in patients with MI was 64.6 (range 15.17-100.15) which was significantly higher than either patients with UA (median=37.6 [7.06-88.65]) or controls (median=25.29 [12.7-43.04]). There were elevated levels of sLOX-1 in acute coronary syndromes. The sLOX-1/oxidized LDL ratio also strongly indicated the diagnosis and a discriminatory force on the ROC curve for myocardial infarction.