β-sheets in serum protein are independent risk factors for coronary lesions besides LDL-C in coronary heart disease patients

Background: Coronary heart disease (CHD) patients with standard low-density lipoprotein cholesterol (LDL-C) remain at risk of cardiovascular events, making it critical to explore new targets to reduce the residual risk. The relationship between beta-sheet conformation and CHD is gaining attention. This study was designed to compare the coronary lesions in CHD patients with varying LDL-C and evaluate whether serum beta-sheets are associated with coronary damage. Methods: Two hundred and one patients diagnosed with stable CHD were recruited and divided into four groups according to LDL-C. Baseline information, coronary lesion-related indicators, and peripheral blood samples were collected. Serum beta-sheet content was determined by thioflavin T fluorescence. Results: The baseline information was comparable in CHD patients with different LDL-C. No difference was found in indicators relevant to coronary lesions among groups. The content of beta-sheet was negatively correlated with LDL-C. Multiple linear regression revealed that serum beta-sheet was positively correlated with coronary lesion when risk factors such as age, smoking, and LDL-C were controlled. Conclusions: This is the first study that reports the serum beta-sheet levels of CHD patients being gradually increased with decreasing LDL-C when coronary lesions were comparable. Serum beta-sheet might exacerbate the coronary lesions in CHD patients independent of known risk factors such as LDL-C.