New research Published in the journey Science Uncovers how scratching aggravates inflammation and swelling in a mouse model of a type of a type of eczema called allergic contact dermatitis.

“At first, these findings see to introduce a paradox: if scratching an itch is bad for us, why does it feel soel so good?” Said Senior Author Daniel Kaplan, MD, Ph.D., Professor of Dermatology and Immunology at the University of Pittsburgh.

“Scratching is often pleasurable, which sugges that, in order to have evolved, this behavior Must provide some kind of benefits. Our Study Helps Resolve This Paradox by providing ES Defense Against Bacterial Skin Infections. “

Allergic Contact Dermatitis is an allergic reaction to allergens or skin irritants – Including poison ivy and certain metals thought as nickel -leading to an itchy, swollen rash. Succumbering to the ofteen-irresistible urge to scratch triggers further inflammation that Worsens Symptoms and Slows healing.

To Figure Out What Drives This Vicious Cycle, Kaplan, First Author andrew Liu, Student in Pitt’s Medical Scientist Training Program, and their TEAM Used Itch-Dr.DUCINS ALERERGENS to Induc Ears of Normal Mice and That that Don’t Get itchy because they lacked an itch-sensing neuron.

When Normal Mice was allowed to scratch, their ears being swollen and filled with inflammatory immune cells called neutrophils. Ingtrist, inflammation and swelling was much milder in normal mice that would be scrast The itch-sensing neuron . This experiment confirmed that scratching further aggravates the skin.

Next, The Researchers Showed that Scratching Causes Pain-Sensing Neurons to Release a Compound Called Substance P. In Turn, Substance P activities Mast Cells, What ARE KEY CORDINATORS Itchines and inflammation via recruitment of neutrophils.

“In contact dermatitis, mast cells are directly activated by allergens, which drives minor inflammation and itchiness,” EXPLAINED Kaplan.

“In response to scratching, the release of p activities mast cells through a second path, so the reason that scratching triggers more inflammation in the skin is a skin is a consalt Ctivated through two pathways. “

Mast cells are criprits in a range of inflammatory skin conditions and allergic reactions, but they’re also also important for Protecting Against Bacteria and Other Pathogens. As such, the researchers wondered if scratching-aduced activation of mast cells could affect the skin microbiome.

In Experiments LED by Co-Author Marlies Meisel, Ph.D., Assistant Professor of Immunology at Pitt, The Team Showed That Scratching Reduced The Amount of Staphylocx Aureus, The Most Common Backet Kin infections, on the skin.

“The finding that scratching improves defense against staphylococcus aureus sugges that it could be beneficial in some contexts,” said kaplan. “But the damage that scratching does to the skin probably outweighs this benefits when itching is chronic.”

Now, The Resarchers are Investigating New Therapies for dermatitis and other inflammatory skin conditions