Researchers in Berlin report that they have discovered the mechanism by which protease inhibitors lead to the onset of diarrhea. 'Studies show that about 20% of protease inhibitor patients get this diarrhea,' says lead researcher Reiner Ullrich. 'It's usually not so serious that the patients have to stop their medication, but it's at least inconvenient.' The researchers discovered that protease inhibitors hasten apoptosis, or cell death, in the epithelial cells lining the intestine, reducing the barrier function of the epithelial lining and leading to the onset of diarrhea. They now plan to look for ways to either avoid triggering cell death, by altering the structure of protease drugs; or find new compounds that prevent apoptosis or that help the remaining cells regenerate more quickly.
