Curcumin, the active component in turmeric, has anti-inflammatory, antioxidant, and wound-healing properties.

Curcumin may be a viable photoprotective adjuvant when delivered through nanoparticles, according to research published by a collaborative team from the George Washington University (GW) School of Medicine and Health Sciences (SMHS) Department of Dermatology and Albert Einstein College of Medicine. 

The study appears in Experimental Dermatology.

With the ongoing rise in ultraviolet radiation-associated skin damage, from accelerated skin aging to increasing skin cancer rates, new sun-protective options are in high demand. Curcumin, the active component in turmeric, has anti-inflammatory, antioxidant, and wound-healing properties. Previous studies have shown it can decrease sunlight-induced inflammation, damage to human skin cells, and the expression of sun-induced collagen destroying matrix metalloproteinases. However, curcumin’s utility has been hindered by poor solubility, rapid degradation, and its unsightly orange-yellow color.

“Because there has not been a new sunscreen filter approved by the U.S. FDA in over 20 years, we have witnessed the emergence of sunscreen adjuvants that don’t fall under the category of a sunscreen per se, rather they focus on repair and/or protection from what injury UV radiation imparts on the skin,” says Adam Friedman, MD, chair and professor of the Department of Dermatology at SMHS. “Though the number of sunscreen filters has remained stagnant, the incidence of skin cancer certainly has not; therefore, we need innovative options that may include both new ingredients and the vehicles that deliver them.”

The team synthesized nanoparticles, which offer sustained topical delivery and enhanced bioavailability, to overcome many of the limitations with curcumin, notably the potential for skin staining. Using a murine model, the team treated groups with either curcumin nanoparticles prior to ultraviolet B radiation exposure or controls, such as unencapsulated curcumin in coconut oil. Twenty-four hours following exposure, the group treated with the curcumin nanoparticles showed less skin reddening than the other experimental groups, including those treated with curcumin not in nanoparticles, and histology and inflammation cytokine analysis of the exposed skin showed less skin cell damage and decreased markers of inflammation as compared to all control groups.

“Our results further reinforce earlier cell-based work underscoring curcumin’s anti-inflammatory properties and highlight its potential both as a photoprotective adjuvant and therapeutic option for other inflammatory skin diseases when delivered through nanoparticles,” adds GW medical student Nagasai Adusumilli, the first author on the study. 

The researchers recommend further investigation into the applications of curcumin alongside sunscreens against UV-induced cellular damage, oxidative stress, and inflammation.