Scratching an itch may feel good, but new research published in the journal Science reveals that it can actually worsen inflammation and swelling in cases of allergic contact dermatitis, a type of eczema. The study, conducted by researchers at the University of Pittsburgh, sheds light on the mechanisms behind this phenomenon.
Lead author Dr. Daniel Kaplan, along with his team, used itch-inducing allergens to induce eczema-like symptoms in mice. They found that scratching the affected areas led to increased inflammation and swelling, caused by the release of a compound called substance P from pain-sensing neurons. This substance activates mast cells, which are responsible for driving inflammation and itchiness by recruiting immune cells called neutrophils.
Interestingly, the researchers also discovered that scratching can have a positive effect on the skin microbiome by reducing the presence of Staphylococcus aureus, a common bacteria involved in skin infections. This suggests that scratching may have a protective role against certain pathogens, although the damage it causes to the skin can outweigh this benefit, especially in cases of chronic itching.
Moving forward, the team is exploring new therapies for dermatitis and other inflammatory skin conditions that target mast cell receptors to suppress inflammation. This research could lead to novel treatments for conditions like rosacea and urticaria, offering new possibilities for managing inflammatory skin disorders.
The study, titled “Scratching promotes allergic inflammation and host defense via neurogenic mast cell activation,” provides valuable insights into the complex relationship between scratching, inflammation, and skin health. By understanding the mechanisms at play, researchers hope to develop more effective strategies for managing inflammatory skin conditions in the future.
For more information, you can access the original study in the journal Science or visit the University of Pittsburgh’s website for additional resources on dermatological research.
