Endothelial cells and blood vessels are major targets for COVID-19-induced tissue injury and spreading to various organs

Table 1 COVID-19 and endothelium/blood vessels

COVID-19 and endothelium/blood vessels
Endothelium and blood vessels are integral parts of COVID-19-induced tissue injury. Their injury is likely due to either direct viral infection and/or cytokine storm triggered by infection of adjacent epithelial cells and inflammatory response[18].
Blood vessels are critical for virus dissemination to distant organs.
Preexisting-impaired endothelial function, e.g., in aging or diabetes are likely predisposing factors COVID-19. Our studies demonstrated that aging gastric mucosa has increased susceptibility to injury and prominent EC abnormalities (decreased VEGF, NGF and impaired mitochondrial function)[19-21].
ECs are critical for vascular regeneration (through angiogenesis and vasculogenesis) during injury/lesions healing and therefore are essential for the delivery of oxygen and nutrients to the healing site[22, 23].
Several growth factors e.g., NGF, IGF-1, HGF and BMD-stem cells may facilitate tissue regeneration in the healing phase[20,24,25].
Long-term effects of COVID-19, its vaccines and treatment on endothelium and vasculature remain to be determined.
Recently, new oral drugs inhibiting viral replication–Molnupiravir (Merck) and Paxlovid (Pfizer) showed significant efficacy in controlling severe COVID-19 infection by inhibiting viral replication. The interim analysis of the latter drug showed an 89% reduction in risk of COVID-19-related hospitalization or death from any cause compared to placebo in patients treated within three-five days of symptom onset[26].

COVID-19: Coronavirus disease 2019; EC: Endothelial cell; VEGF: Vascular endothelial growth factor; NGF: Nerve growth factor.