Study Suggests Black Raspberries May Help Control Contact Dermatitis
Understanding Occupational Contact Dermatitis
Have you ever experienced an itchy rash after coming into contact with something at work? You are not alone; occupational contact dermatitis affects approximately 15 to 20% of adults. This condition is triggered by exposure to various items, including rubber gloves, dyes, and jewelry. A specific type of this condition, known as contact hypersensitivity, is characterized by a delayed reaction to substances that are generally well-tolerated. Symptoms include redness, scaling, swelling, and itchiness of the skin, with management typically involving corticosteroids.
Research Findings from Ohio State University
Researchers at Ohio State University have recently discovered that incorporating black raspberries into the diet can reduce inflammation associated with contact hypersensitivity in mice. Dr. Steve Oghumu, the senior researcher and assistant professor of pathology, remarked, “A lot of times, treatments [for contact hypersensitivity] are directly applied to the skin – things like steroids. And, it was interesting that the mere consumption of a fruit can achieve the same effects.” The study was published in the journal *Nutrients* earlier this month.
Previous Research on Black Raspberries
Dr. Oghumu and his team have been investigating the impact of compounds found in black raspberries on immune cells, particularly in the context of preventing oral cancer. Earlier studies indicated that a diet rich in black raspberries could reduce inflammation in various cancer types. This prompted the team to explore the effects of a black raspberry-enriched diet on contact hypersensitivity using pre-clinical mouse models.
Composition and Experimental Design
Black raspberries are high in anthocyanins, the pigments responsible for their dark color, which are also found in blueberries and black soybeans. The Ohio State researchers focused on the effects of whole black raspberries and protocatechuic acid (PCA), the primary anthocyanin in black raspberries. Different groups of mice were fed black raspberry powder, PCA, or no dietary supplement, and were subsequently exposed to DNFB, a chemical that triggers a response similar to contact hypersensitivity in humans. After three weeks, the mice were re-exposed to DNFB on one ear.
Results and Immune Response Changes
The study revealed that mice receiving either the black raspberry supplement or PCA exhibited reduced swelling in the ear exposed to DNFB, compared to those without the supplement. The researchers also investigated the changes in immune response, suggesting that the reduced swelling was linked to decreased migration and maturation of dendritic cells, which are pivotal in relaying inflammation signals in the immune system. During contact hypersensitivity dermatitis, exposure to an irritant or allergen activates the immune response, leading to inflammation and itchiness. Controlling this inflammation could potentially alleviate dermatitis.
Implications of the Findings
Dr. Oghumu emphasized the complexity of the immune system, stating, “The immune system is very complex, with multiple players. Once you begin to identify the unique cells affected by the berries, it helps us to understand how berries inhibit inflammation. A lot of adverse effects we observe are not solely due to the pathogens or allergens, but rather the body’s response to these triggers. Managing that response is one way to address these diseases, and black raspberries appear to play a role in this.”
Future Research Directions
The findings from this study highlight the potential impact of diet in combating diseases ranging from cancer to contact hypersensitivity dermatitis. Although further research is necessary to pinpoint specific molecules in raspberries that contribute to reduced inflammation, this study establishes a foundation for future investigations.
References
Original study: Anderson, Kelvin & Ryan, Nathan & Siddiqui, Arham & Pero, Travis & Volpedo, Greta & Cooperstone, Jessica & Oghumu, Steve. (2020). Black Raspberries and Protocatechuic Acid Mitigate DNFB-Induced Contact Hypersensitivity by Down-Regulating Dendritic Cell Activation and Inhibiting Mediators of Effector Responses. *Nutrients*. 12. 1701. 10.3390/nu12061701.
Press release: https://www.eurekalert.org/pub_releases/2020-07/osu-ims070220.php
Image by Alina Kuptsova from Pixabay