Researchers find common protein in skin that activates itch-associated neurons

Periostin, a commonly expressed protein in skin, can directly activate itch-connected neurons in the skin, according to the researchers from North Carolina State University.

From the study, the researchers found that blocking periostin receptors on these neurons reduced the itch response in a mouse model of atopic dermatitis or eczema.

Itch sensations are transmitted from neuronal projections in the skin through the dorsal root ganglia (DRG) -- which are clusters of sensory cells located at the root of the spinal nerves -- then to the spinal cord.

The study was appeared in Cell Reports and was funded by NC State's startup fund.

Santosh Mishra, assistant professor of neuroscience at NC State and lead author of a paper on the work said that "We have found that periostin, a protein that is produced abundantly in the skin as part of an allergic response, can interact directly with sensory neurons in the skin, effectively turning on the itch response."

"Additionally, we identified the neuronal receptor that is the initial connection between periostin and itch response," Mishra added.

Mishra and with a team including colleagues from NC State, Wake Forest University and Duke University identified a receptor protein called avb3, which is expressed on sensory neurons in skin, as the periostin receptor.

Research conducted in a chemically-induced mouse model of atopic dermatitis, the team found that exposure to common allergens such as dust mites increased periostin production in the skin, exacerbating the itch response.

However, when the researchers "turned off" the receptor protein, the itch was significantly reduced.

"Periostin and its receptor connect the skin directly to the central nervous system," said Mishra.

"We have identified the first junction in the itch pathway associated with eczema. If we can break that connection, we can relieve the itch," he added.