Calcineurin Inhibitors and reduced incidence of Dementia


brain and puzzle

Sometimes the biggest scientific discoveries are made when ideas from different fields collide, especially when they’re not even working on the same question. We call this, “collision science.” At our university, a neuroscientist studying dementia and a transplant surgeon were having a casual conversation when they realized that transplant patients have lower rates of dementia.  They thought it could be the drugs these patients take to keep their immune systems from “rejecting” the new organ.  

One of those drugs blocks a protein called calcineurin or CN. That’s because CN activates the immune system, but it’s also involved in plaque formation in the brain that contributes to Alzheimer’s disease.  In lab experiments with rats that have problems forming memories, when CN is blocked from acting, the animals recover their memory function.  

So, a graduate student reviewed the health records of more than two hundred million patients to pull fifty thousand control patients sixty-five and older. They then pulled nearly eighty thousand transplant patients of the same age bracket and compared the two groups. These transplant patients were all treated with CN inhibitors and their hunch was right. They all had lower rates of dementia.   

There’s more reason to be optimistic. All three drugs have been approved by the FDA for human use. So, there’s a much shorter runway and cost to human trials.  This example of collision science shows how innovative we can be when we collaborate to solve some of our biggest challenges.    

We are Drs. David Niesel and Norbert Herzog, at UTMB and Quinnipiac University, where biomedical discoveries shape the future of medicine.   For much more and our disclaimer go to or subscribe to our podcast. Sign up for expanded print episodes at or our podcasts at:  Medical Discovery News ( 

Thanks to Giulio Taglialatela, PhD and Jacqueline Silva for their assistance with this story.  Ms. Silva will receive her PhD from UTMB in 2024 

More Information

Reduced Prevalence of Dementia in Patients Prescribed Tacrolimus, Sirolimus, or Cyclosporine
Evidence suggests patients prescribed calcineurin inhibitors (CNIs) have a reduced prevalence of dementia, including Alzheimer’s disease (AD); however, this result has never been replicated in a large cohort and the involved mechanism(s) and site of action (central versus periphery) remain unclear.