It's the Brian Lara Show on WNYC. Good morning again everyone. Some new research shed slight

on distinct biological changes in the bodies of people with long COVID. And maybe offer

some hope for folks who suffered with debilitating cognitive symptoms, weeks, months, even years

after coming down with COVID. In a study published in the journal Cell, a team of researchers at

University of Pennsylvania proposed a link between diminished levels of serotonin in the body

and some cognitive and neurological long COVID symptoms. Even after acute COVID symptoms

peter out, these researchers say, remnants of the virus linger in the gut and trigger a reduction

in serotonin. So we'll spend a few minutes now delving into the research and discussing how it

could help clinicians diagnose patients and develop effective treatments for long COVID.

Joining me now, Dr. Daniel Griffin, MD, PhD, infectious disease physician, with a PhD also in

molecular medicine, researcher at Columbia, Chief of the Division of Infectious Disease at Optum,

President of the Group, parasites without borders and co-host of the podcast, this week in

virology. Dr. Griffin, always good of you to give us your time and expertise. Welcome back to WNYC.

Oh, thank you, Brian. It was nice to be back.

By way of background to start, what role does serotonin play in the body and how might depleted

serotonin contribute to long COVID symptoms as outlined in this new study?

Yes, serotonin is, well, it's involved in a lot of things, but I would say our listeners are

probably most familiar with serotonin's role in mental health and really the revolution that

the serotonin targeting SSRI medicines really brought us with regard treatment of depression.

So serotonin's involved in the brain, it's involved in mood, it's also involved in digestion,

it really has a lot of rules. And what are some of the specific neurological and cognitive

symptoms of long COVID that depleted serotonin could explain?

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