COVID-19 infection is linked to reduced brain wakefulness signals and lasting loss of nerve cell markers in thinking areas

SARS-CoV-2 infection may suppress hypothalamic orexin signaling while causing persistent cortical neuronal injury in preclinical models.

This preclinical mouse and in vitro study tested K18-hACE2 and wild-type BALB/c mice, compared SARS-CoV-2 with influenza A, and assessed viral RNA, cortical NeuN abundance, hypothalamic orexin expression, and orexin-A/B supplementation.

The work is limited to mouse and in vitro models, so it does not show that orexin dysfunction causes Long COVID symptoms or that supplementation helps patients.