New route for taming poison ivy’s itch

Abstract

A casual brush with poison ivy can cause agonizing itching for an estimated 10 to 50 million Americans every year. But exactly how the plant inflicts such misery is still somewhat of a mystery. By exposing mice to poison ivy’s oily allergen urushiol, Sven-Eric Jordt of Duke University and colleagues have now pinpointed a molecular pathway that helps transmit an itch signal through nerve cells. Antihistamines and corticosteroids are commonly prescribed to people with a poison ivy rash. But “the antihistamines just don’t work,” Jordt says, and although steroids help with inflammation, they’re ineffective against itch. “So from all perspectives, it is necessary to revisit the mechanisms and identify a more efficient treatment,” he adds. The researchers looked for genes that were transcribed at higher levels in mice whose skin was brushed with urushiol compounds compared with nonexposed mice (Proc. Natl. Acad. Sci. USA 2016, DOI: 10.1073/pnas.1606608113). Unsurprisingly, several genes