Involvement of oxidative stress in post-acute sequelae of COVID-19: clinical implications

Oxidative stress (OS) plays a key role in the pathophysiology of COVID-19 and may be associated with sequelae after severe SARS-CoV-2 infection. This study evaluated OS and inflammation biomarkers in blood from individuals with post-acute sequelae of COVID-19 (PASC). 64 male and female participants were distributed into three groups: healthy individuals (n = 20), acute COVID-19 patients (symptoms for <3 weeks, n = 15), and PASC patients (symptoms for >12 weeks, n = 29). Analyses included inflammatory cytokines, myeloperoxidase (MPO) activity, and OS markers, such as superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), gamma-glutamyl transferase (GGT), reduced glutathione (GSH), uric acid (UA), thiobarbituric acid reactive substances (TBARS), and protein carbonyls (PC). Individuals with PASC showed increased IL-6 and IL-8. Both COVID-19 groups exhibited decreased SOD and CAT. GST decreased only in the acute group. Elevated GGT and GSH were found in the PASC group. High UA levels were observed in PASC individuals. There were no changes in TBARS values ⁣⁣in the PASC group. However, PC concentrations were elevated only in this group. Correlations were identified between inflammatory markers and OS parameters. These findings suggest that individuals with PASC pronounced OS, which potentially exacerbates disease complications. Monitoring OS biomarkers could aid in patient prognosis and management.