Intranasal Administration of SARS-CoV-2 ORF8 Accessory Protein Increases Blood Pressure and Oxidative Stress in Different Tissues of Male BALB/c Mice.

SARS-CoV-2 is the etiological agent responsible for COVID-19. While most research has focused on structural proteins, the accessory protein Open Reading Frame 8 (ORF8) has attracted attention for its role in immune evasion and the induction of a cytokine storm. Although the exact mechanisms underlying viral pathogenicity remain to be elucidated, oxidative stress has been proposed as a key contributing factor. In this study, we evaluated the effect of intranasal administration of ORF8 on arterial blood pressure and the antioxidant system in different organs of male BALB/c mice at 2- or 8 weeks post-administration. A significant increase in blood pressure and renal total antioxidant capacity was observed in the 8-week group, and decreased catalase activity in the prefrontal cortex was observed in the 2-week group. These findings suggest that ORF8 may contribute to long-term renal alterations and potentially to mechanism relevant to cognitive dysfunction associated with COVID-19.