‘Super Melanin’ Heals Skin Injuries from Sunburn

Imagine a skin cream that heals damage occurring throughout the day when your skin is exposed to sunlight or environmental toxins. That’s the potential of a synthetic, biomimetic melanin developed by scientists at Northwestern University.

In a new study, the scientists show that their synthetic melanin, mimicking the natural melanin in human skin, can be applied topically to injured skin, where it accelerates wound healing. These effects occur both in the skin itself and systemically in the body.

When applied in a cream, the synthetic melanin can protect skin from sun exposure and heals skin injured by sun damage or chemical burns, the scientists said. The technology works by scavenging free radicals, which are produced by injured skin such as a sunburn. Left unchecked, free radical activity damages cells and ultimately may result in skin aging and skin cancer.

The study will be published Nov. 2 in Nature npj Regenerative Medicine.

Melanin in humans and animals provides pigmentation to the skin, eyes and hair. The substance protects your cells from sun damage with increased pigmentation in response to sunlight — a process commonly referred to as tanning. That same pigment in your skin also naturally scavenges free radicals in response to damaging environmental pollution from industrial sources and automobile exhaust fumes.

When the scientists created the synthetic melanin engineered nanoparticles, they modified the melanin structure to have higher free radical scavenging capacity. Once applied to the skin, the melanin sits on the surface and is not absorbed into the layers below.

The scientists, who have been studying melanin for nearly 10 years, first tested their synthetic melanin as a sunscreen.

Lu envisions the synthetic melanin cream being used as a sunscreen booster for added protection and as an enhancer in moisturizer to promote skin repair.

The scientists used a chemical to create a blistering reaction to a human skin tissue sample in a dish. The blistering appeared as a separation of the upper layers of the skin from each other.

They waited a few hours, then applied their topical melanin cream to the injured skin. Within the first few days, the cream facilitated an immune response by initially helping the skin’s own radical scavenging enzymes to recover, then by halting the production of inflammatory proteins. This initiated a cascade of responses in which they observed greatly increased rates of healing. This included the preservation of healthy skin layers underneath. In samples that did not have the melanin cream treatment, the blistering persisted.

Melanin also absorbs heavy metals and toxins. “Although it can act this way naturally, we have engineered it to optimize absorption of these toxic molecules with our synthetic version,” Gianneschi said.

The scientists are pursuing clinical translation and trials testing for efficacy of the synthetic melanin cream. In an initial step, the scientists recently completed a trial showing that the synthetic melanins are non-irritating to human skin.

Given their observation that melanin protects biologic tissue from high energy radiation, they surmise that this could be an effective treatment for skin burns from radiation exposure.

The promising work may well provide treatment options for cancer patients in the future, undergoing radiation therapy.

Sources:

Dauren Biyashev, Zofia E. Siwicka, Ummiye V. Onay, Michael Demczuk, Dan Xu, Madison K. Ernst, Spencer T. Evans, Cuong V. Nguyen, Florencia A. Son, Navjit K. Paul, Naneki C. McCallum, Omar K. Farha, Stephen D. Miller, Nathan C. Gianneschi, Kurt Q. Lu. Topical application of synthetic melanin promotes tissue repair. npj Regenerative Medicine, 2023; 8 (1) DOI: 10.1038/s41536-023-00331-1

Northwestern University. (2023, November 2). ‘Super melanin’ heals skin injuries from sunburn, chemical burns. ScienceDaily. Retrieved November 6, 2023 from www.sciencedaily.com/releases/2023/11/231102135130.htm

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