Oxidative stress (OS) resulting from an imbalance between reactive oxygen species (ROS) generation and antioxidant defenses plays a pivotal role in vascular diseases such as atherosclerosis and hypertension. ROS derived from NADPH oxidase, mitochondria, and xanthine oxidase promote endothelial dysfunction by inducing lipid and protein oxidation, apoptosis, and pro-inflammatory signaling, thereby enhancing smooth muscle proliferation and atherogenesis. This review summarizes the molecular mechanisms linking OS to vascular injury and aims to systematically elucidate the role of OS in vascular diseases, with a specific focus on critiquing the current challenges in translating biomarkers to clinical practice and the emerging trends in personalized antioxidant therapy. Particular attention is given to biomarkers of oxidative stress, including those assessing antioxidant enzyme activity and oxidative damage products, which possess potential for clinical use. Therapeutic strategies targeting OS, including dietary and pharmacological antioxidants, show promise in improving vascular health, although clinical outcomes have been inconsistent and it is necessary to resolve the standardization and validation of these biomarkers, develop precise targeted therapies against specific ROS sources (e.g., NOX inhibitors, mitochondrial antioxidants), and explore personalized clinical trials based on redox stratification. Overall, OS is a central mediator in vascular pathology, and progress in biomarker validation and targeted therapies will be essential to translate current knowledge into effective prevention, diagnosis, and treatment of cardiovascular diseases. Personalized approaches based on accurate redox profiling may enhance efficacy.
Decision-making is challenging in patients with chest pain and normal high-sensitivity cardiac troponin T (hs-cTnT; <99th percentile; <14 ng/L) at hospital arrival. Most of these patients might be discharged early. We investigated clinical data and hs-cTnT concentrations for risk stratification. This is a retrospective study including 4476 consecutive patients presenting to the emergency department with chest pain and first normal hs-cTnT. The primary endpoint was one-year death or acute myocardial infarction, and the secondary endpoint added urgent revascularization. The number of primary and secondary endpoints was 173 (3.9%) and 252 (5.6%). Mean hs-cTnT concentrations were 6.9 ± 2.5 ng/L. Undetectable (<5 ng/L) hs-cTnT (n = 1847, 41%) had optimal negative predictive value (99.1%) but suboptimal sensitivity (90.2%) and discrimination accuracy (AUC = 0.664) for the primary endpoint. Multivariable analysis was used to identify the predictive clinical variables. The clinical model showed good discrimination accuracy (AUC = 0.810). The addition of undetectable hs-cTnT (≥ or <5 ng/L; HR, hazard ratio = 3.80; 95% CI, confidence interval 2.27–6.35; p = 0.00001) outperformed the clinical model alone (AUC = 0.836, p = 0.002 compared to the clinical model). Measurable hs-cTnT concentrations (between detection limit and 99th percentile; per 0.1 ng/L, HR = 1.13; CI 1.06–1.20; p = 0.0001) provided further predictive information (AUC = 0.844; p = 0.05 compared to the clinical plus undetectable hs-cTnT model). The results were reproducible for the secondary endpoint and 30-day events. Clinical assessment, undetectable hs-cTnT and measurable hs-cTnT concentrations must be considered for decision-making after a single negative hs-cTnT result in patients presenting to the emergency department with acute chest pain.
Oxidative stress (OS), resulting from an imbalance between reactive oxygen species (ROS) generation and antioxidant defenses, plays a pivotal role in vascular diseases such as atherosclerosis and hypertension. ROS derived from NADPH oxidase, mitochondria, and xanthine oxidase promote endothelial dysfunction by inducing lipid and protein oxidation, apoptosis, and pro-inflammatory signaling, thereby enhancing smooth muscle proliferation and atherogenesis. This review summarizes the molecular mechanisms linking OS to vascular injury and highlights the interplay between ROS and inflammation in the progression of cardiovascular disease. Particular attention is given to biomarkers of oxidative stress, including those assessing antioxidant enzyme activity and oxidative damage products, which hold potential for clinical use. However, challenges remain regarding their standardization and variability influenced by biological and environmental factors. Therapeutic strategies targeting OS, including dietary and pharmacological antioxidants, show promise in improving vascular health, although clinical outcomes have been inconsistent. Personalized approaches based on accurate redox profiling may enhance efficacy. Overall, OS is a central mediator in vascular pathology, and progress in biomarker validation and targeted therapies will be essential to translate current knowledge into effective prevention, diagnosis, and treatment of cardiovascular diseases.
22 August 2023 in The American Journal of Cardiology