Abstract: Objective To analyze the correlation of copper death inducer ferredoxin 1 (FDX1) and lipoic acid (LA) with the occurrence and severity of coronary atherosclerosis and explore their roles in coronary heart disease (CHD). Methods We analyzed the data of 226 patients undergoing coronary artery angiography (CAG) in our hospital between October, 2021 and October, 2022, including 47 patients with normal CAG findings (control group) and 179 patients with mild, moderate or severe coronary artery stenosis (CHD group). Serum FDX1 and LA levels were determined with ELISA for all the patients. We also examined pathological changes in the aorta of normal and ApoE-/- mice using HE staining and observed collagen fiber deposition with Sirius red staining. Immunohistochemistry was used to detect the expression and distribution of FDX1 and LA in the aorta, and RT-PCR was performed to detect the expressions of FDX1, LIAS and ACO2 mRNAs in the myocardial tissues. Results Compared with the control patients, CHD patients had significantly lower serum FDX1 and LA levels, which decreased progressively as coronary artery stenosis worsened (P<0.01) and as the number of involved coronary artery branches increased (P<0.05). Serum FDX1 and LA levels were positively correlated (r=0.451, P<0.01) and they both negatively correlated with the Gensini score (r=-0.241 and -0.273, respectively; P<0.01). Compared with normal mice, ApoE-/- mice showed significantly increased lipid levels (P<0.01) and atherosclerosis index, obvious thickening, lipid aggregation, and collagen fiber hyperplasia in the aorta, and significantly reduced expressions of FDX1, LA, LIAS, and ACO2 (P<0.05). Conclusion Serum FDX1 and LA levels decrease with worsening of coronary artery lesions, and theirs expressions are correlated with coronary artery lesions induced by hyperlipidemia.

Key words: coronary heart disease; severity of lesion; hyperlipidemia; ferredoxins 1; lipoic acid