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An unorthodox pathophysiology of severe cases of COVID-19 the weak heme hypothesis

Mohamed Zamd1, Naoufal Mtioui1, Omar Maoujoud2

  • 1Laboratory of Cellular, Molecular, Inflammatory, Degenerative and Oncologic Pathophysiology (LCMIDOP), Faculty of Medicine and Pharmacy, Hassan II University Casablanca, Morocco.

American Journal of Blood Research
|January 25, 2021
PubMed

Insights

Severe COVID-19 cases may stem from free heme toxicity, exacerbated by air pollution and genetic factors like unstable hemoglobin. This hypothesis offers new insights into disease severity and geographical patterns.

Area of Science:

  • Pathophysiology
  • Environmental Health
  • Genetics

Background:

  • The COVID-19 pandemic is characterized by a significant number of severe cases, straining healthcare systems globally.
  • Understanding the underlying pathophysiology of severe COVID-19 is crucial for effective management and prevention.

Purpose of the Study:

  • To propose a pathophysiological hypothesis explaining the key features of severe COVID-19 cases.
  • To explore the roles of free heme toxicity, air pollution, and hemoglobin variants in severe disease.

Main Methods:

  • Review and synthesis of existing clinical and biological data on severe COVID-19.
  • Comparison of severe COVID-19 manifestations with acute porphyria.
  • Analysis of geographical distribution patterns in relation to air quality.

Main Results:

  • Severe COVID-19 may be explained by free heme toxicity overwhelming antioxidant defenses, similar to acute porphyria.
  • Geographical variations in severe cases correlate with air freshness or pollution levels.
  • An unstable hemoglobin variant might explain the lower rate of severe cases by reacting to SARS-CoV-2-induced pneumonia.

Conclusions:

  • A combined hypothesis suggests that air pollution and free heme toxicity, driven by interactions with unstable hemoglobin variants and SARS-CoV-2 infection, best explain severe COVID-19.
  • Further research is needed to validate this hypothesis and inform clinical and policy decisions.

Keywords:
Severe COVID-19air pollutionantioxidant systemsfree heme toxicity

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