A Multiple-Hit Hypothesis Involving Reactive Oxygen Species and Myeloperoxidase Explains Clinical Deterioration and Fatality in COVID-19

© The author(s)..

Multi-system involvement and rapid clinical deterioration are hallmarks of coronavirus disease 2019 (COVID-19) related mortality. The unique clinical phenomena in severe COVID-19 can be perplexing, and they include disproportionately severe hypoxemia relative to lung alveolar-parenchymal pathology and rapid clinical deterioration, with poor response to O2 supplementation, despite preserved lung mechanics. Factors such as microvascular injury, thromboembolism, pulmonary hypertension, and alteration in hemoglobin structure and function could play important roles. Overwhelming immune response associated with "cytokine storms" could activate reactive oxygen species (ROS), which may result in consumption of nitric oxide (NO), a critical vasodilation regulator. In other inflammatory infections, activated neutrophils are known to release myeloperoxidase (MPO) in a natural immune response, which contributes to production of hypochlorous acid (HOCl). However, during overwhelming inflammation, HOCl competes with O2 at heme binding sites, decreasing O2 saturation. Moreover, HOCl contributes to several oxidative reactions, including hemoglobin-heme iron oxidation, heme destruction, and subsequent release of free iron, which mediates toxic tissue injury through additional generation of ROS and NO consumption. Connecting these reactions in a multi-hit model can explain generalized tissue damage, vasoconstriction, severe hypoxia, and precipitous clinical deterioration in critically ill COVID-19 patients. Understanding these mechanisms is critical to develop therapeutic strategies to combat COVID-19.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:17

Enthalten in:

International journal of biological sciences - 17(2021), 1 vom: 01., Seite 62-72

Sprache:

Englisch

Beteiligte Personen:

Goud, Pravin T [VerfasserIn]
Bai, David [VerfasserIn]
Abu-Soud, Husam M [VerfasserIn]

Links:

Volltext

Themen:

712K4CDC10
Coronavirus. COVID-19
EC 1.11.1.7
Free iron
Hypochlorous Acid
Journal Article
Myeloperoxidase, HOCl
Peroxidase
Reactive Oxygen Species
Reactive oxygen species
Review

Anmerkungen:

Date Completed 19.01.2021

Date Revised 30.03.2024

published: Electronic-eCollection

Citation Status MEDLINE

doi:

10.7150/ijbs.51811

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM319548317