Influence of oxidative stress on the progression of carotid atherosclerosis

Introduction and objective: oxidative Stress (OS) has proven to have a clear impact on the development of atherosclerotic plaques due to the damage it causes to vascular endothelium. The aim of this study is to conduct a research on key oxidative stress markers in patients with carotid artery atherosclerotic disease as a sign of vulnerability, analyze the implications of the redox status and mitochondrial metabolic state in carotid artery atherosclerotic disease, and its relationship with neurological clinical presentation. Patients and methods: atherosclerotic plaques obtained from carotid endarterectomy patients (both asymptomatic and symptomatic) performed the Department of Angiology, Vascular and Endovascular Surgery of Hospital Clinico Universitario de Valladolid, Spain in 2020 will be examined. The clinical-demographic variables and the presence of neurological symptoms will be recorded. Anatomical and hemodynamic characteristics will be studied using Doppler ultrasound and coronary computed tomography angiography (CCTA) preoperatively. Atherosclerotic plaques will be analyzed as estimators of the degree of lipid peroxidation showing the redox state. A sample size of 45 speciments from each group has been estimated with a loss to follow-up rate of 5 %. Inter-group differences will be studied using the chi-square and Student's t tests to establish the relationship between redox potential and morphological characteristics of the atheromatous plaque. SPSS 27.0 statistical software will be used, with a significance level set at p < 0.05. Results: calcified atherosclerotic plaques showed higher antioxidant capacity compared to non-calcified plaques in the ABTS parameter (2,2-azino-bis(3-ethylbenzthioziozline-6-sulfonic)) (2635.08 vs 2803.28), with statistically significant relationship (p = 0.007). They also exhibited greater antioxidant defense when analyzing catalase activity (160.73 vs 175.13) and SOD activity (1.11 vs 1.49) (p = 0.049). In the study of the energy metabolism of carotid atherosclerotic plaques, it was observed that lactate levels were higher in non-calcified plaques ( 11.45 vs 8.57) (p = 0.001). Plasma levels of uric acid (1.48 vs. 2.33) and catalase activity (146.79 vs 176.81) were significantly higher in patients with neurological symptoms (p = 0.001 and p = 0.025, respectively). Conclusions: homogeneous and calcified carotid artery atherosclerotic plaques exhibit higher antioxidant capacity and defense compared to non-calcified and heterogeneous plaques. Patients with neurological symptoms showed atherosclerotic plaques with lower antioxidant capacity and defenses compared to asymptomatic neurological patients.