Abstract
INTRODUCTION: Oxidative stress (OS) occurs when there is an imbalance between reactive oxygen species (ROS) production and the body's ability to neutralize them. This can lead to cellular damage and is associated with aging and various diseases. Glutathione (GSH) acts as a vital non-enzymatic antioxidant, while enzymes such as glutathione S-transferase (GST) and glutathione reductase (GR) help maintain the body's redox balance. OS from viruses, including coronavirus, can disrupt inflammation regulation and cause prolonged tissue damage. AIM: This study examines GSH levels and the activities of GST and R-GSSG in the erythrocytes of COVID-19 patients compared to those of healthy controls. MATERIALS AND METHODS: The study involved 85 COVID-19 patients (42 females and 43 males), with blood samples collected at the time of disease detection and at 7, 14, and 28 days later. The control group included 85 healthy individuals. Antioxidant levels (GSH, GST, R-GSSG) were measured using spectrophotometric methods. RESULTS: COVID-19 patients exhibited a significant decrease in GSH concentration (p < 0.001) and an increase in R-GSSG (p < 0.001) and GST (p = 0.046) activity. Lower GSH levels correlated with a higher risk of death (p = 0.008). Multivariate analysis revealed relationships between GSH and factors such as time since detection, survival rate, hospital stay, and disease severity. CONCLUSION: COVID-19 disrupts antioxidant enzyme balance, potentially worsening disease severity and increasing mortality risk, especially in older patients.