Scientists have uncovered a dedicated sensory system linking fine vellus-like hairs to the sensation of mechanical itch. The discovery, made in mouse models, may explain why peach fuzz sometimes triggers itching and could guide new treatments for chronic skin conditions.
Researchers at the University of Michigan identified a previously unknown type of hair in mice along with specialized nerve cells that transmit mechanical itch signals. These vellus-like hairs resemble the fine peach fuzz covering much of the human body.
In experiments, mice with chronic skin inflammation similar to eczema scratched less when the neurons were removed or switched off. The team used a small thread loop to stimulate the hairs and confirmed the response by activating the neurons with blue light.
Bo Duan, associate professor in the Department of Molecular, Cellular, and Developmental Biology, said the pathway plays an important role in both acute and chronic itch. He noted that current treatments are less effective against persistent itch linked to inflammation.
The study, supported in part by the National Institutes of Health, was published in the journal Neuron. Evidence suggests humans possess similar genes and neuron responses, though direct testing in people has not occurred.
