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bioRxiv · 10.1101/2021.12.30.474561

Melatonin drugs inhibit SARS-CoV-2 entry into the brain and virus-induced damage of cerebral small vessels

Abstract

COVID-19 is a complex disease with short- and long-term respiratory, inflammatory and neurological symptoms that are triggered by the infection with SARS-CoV-2. Invasion of the brain by SARS-CoV-2 has been observed in humans and is postulated to be involved in post COVID condition. Brain infection is particularly pronounced in the K18-hACE2 mouse model of COVID-19. Here, we show that treatment of K18-hACE2 mice with melatonin and two melatonin-derived marketed drugs, agomelatine and ramelteon, prevent SARS-CoV-2 entry in the brain thereby reducing virus-induced damage of small cerebral vessels, immune cell infiltration and brain inflammation. Brain entry of SARS-CoV-2 through endothelial cells is prevented by melatonin through allosteric binding to human angiotensin-converting enzyme 2 (ACE2), which interferes with the cell entry receptor function of ACE2 for SARS-CoV-2. Our findings open new perspectives for the repurposing of melatonergic drugs in the prevention of brain infection by SARS-CoV-2 and COVID-19-related long-term neurological symptoms.

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BibTeXRIS

Cecon, E., Fernandois, D., Renault, N., Coelho, C. F. F., Wenzel, J., Bedart, C., Izabelle, C., Gallet, S., Le Poder, S., Klonjkowski, B., Schwaninger, M., PREVOT, V., Dam, J., Jockers, R.. 2022-01-03. Melatonin drugs inhibit SARS-CoV-2 entry into the brain and virus-induced damage of cerebral small vessels. https://doi.org/10.1101/2021.12.30.474561

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