Products of oxidative stress in the blood of patients with nervous-system diseases after coronavirus infection

Introduction . Coronavirus infection is accompanied by various neurological complications in which oxidative stress and inflammation play a role.Aim. To clarify the relationship between previous coronavirus infection and the levels of oxidative-stress products and pro-inflammatory interleukins in patients with nervous-system diseases. Materials and methods . The study involved 158 patients with nervous-system diseases; 47 had a history of COVID-19. The comparison group consisted of 26 participants without clinical signs of acute or chronic disease, matched for age and sex. The concentrations of oxidative-stress products in blood were determined using UV spectroscopy and colorimetric methods. Results . Oxidative-stress products were elevated in patients with nervous-system diseases compared with healthy individuals, but no significant differences were found between patients with and without prior coronavirus infection. Only in the subgroup with central nervous-system diseases, post COVID-19 patients had diene conjugate levels 44% higher (p = 0.019) and conjugated diene and ketodiene levels 56% higher (p = 0.050) than patients without COVID-19. Lipid-oxidation products differed among subgroups with acute cerebrovascular accidents, central, and peripheral nervous-system diseases. In patients with acute cerebrovascular accidents and no history of COVID-19, levels of diene conjugates were 81% higher (p = 0.032), conjugated dienes and ketodienes 72% higher (p = 0.042), and lipid hydroperoxides 45% higher (p = 0.016) than in central nervous-system disease. Among post COVID patients, lipid-hydroperoxide levels in the acute cerebrovascular subgroup (80.0 ± 9.37 nmol mL⁻¹) were 37% (p = 0.03) and 32% (p = 0.03) higher than in the central and peripheral nervous-system subgroups (59.9 ± 7.07 and 62.2 ± 3.60 nmol mL⁻¹, respectively). Strong correlations between blood levels of pro-inflammatory interleukins and oxidatively modified lipids in post-COVID patients were most significant for IL-6 and IL-10. Conclusion . Moderate oxidative-stress manifestations in patients with nervous-system diseases are largely attributable to the underlying disorders rather than to prior coronavirus infection. In the post COVID period, these patients retain an association between oxidative stress and inflammation.