2023, 3(1): 37-41.
doi: 10.2478/fzm-2023-0006
Objective Clinical manifestation of the inflammatory process in its relation to biochemical markers (total cysteine [Cys], cysteine-glycine [CysGly], glutathione [GSH], glutamate-cysteine [Glu-Cys], homocysteine [Hcy], the ratio of reduced to oxidized glutathione [GSH/GSSG], the ratio of reduced to oxidized cysteine [CySH/CySS], malondialdehyde-oxidized low-density lipoproteins [MDA-oxLDL]) has been studied in patients with coronavirus disease 2019 (COVID-19). Material and methods 48 patients with mild to severe COVID-19 and 20 healthy volunteers were included in our research. The participants were divided into 4 experimental groups according to inflammation intensity estimated based on the serum levels of interleukin 6 (IL-6). Results All 4 groups showed the prevalence of male patients and elevated serum levels of IL-6 (by 54.6%). There was no comorbidity in patients with mild COVID-19 (nasopharyngitis symptoms) and in healthy control subjects. 50% of patients with lung damage had accompanying diseases. Alterations of aminoethyl metabolism were detected in COVID-19 patients: as reflected by the decreased levels of Cys, CysGly, and Glu-Cys and the increased levels of GSH as compared to the control group. Conclusion Elevation of IL-6 over 7.5 pg/mL was associated with decreased GSH/GSSG and CySH/CySS ratios indicating enhanced oxidative stress and was followed by protein oxidation, specifically MDA-oxLDL.