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Hypothesis of COVID-19 Therapy with Sildenafil
Limodio Mario1, Menicagli Roberto2, Limodio Marta3
1Researcher, UOC, Infectious and Tropical Diseases, Spaziani Hospital, Frosinone, Italy.
Backgound:
Bacterial or viral infections often cause acute and severe systemic inflammation, which affects the lungs lipopolysaccharide (LPS), a pathogenic component of the membrane of gram-negative bacteria, stimulates active innate immune cells, monocytes, macrophages to produce inducible nitric oxide synthase (iNOS). Excess production of this compound occurs in COVID-19 resulting in inflammatory cascade and thromboembolism. We intend to propose the use of sildenafil to reduce this production.
Method:
The analysis of biochemical pathways shows that viral infection produces a high amount of nitric oxide (NO), with an acute inflammatory process.
Results:
In the case of COVID-19 infection we verified that numerous biochemical processes activate a cascade of inflammatory processes through the activation of iNOS with uncontrolled generation of (NO).
Conclusions:
iNOS is the cause of damage to host cells with a consequent pulmonary thromboembolic lung phenomenon in a contest of interstitial pneumonia. This study proposes the use of sildenafil to counter the inflammatory cascade and thromboembolic episodes.
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