UV Protection Potential of Methylene Blue for Human Skin and Coral Reef Health

Xiong, ZM., Mao, X., Trappio, M. et al. UV protective potential of methylene blue for human skin and coral reef health. SCI Rep 11, 10871 (2021). https://doi.org/10.1038/s41598-021-89970-2

Commentary

This study suggested that methylene blue (MB) could be offered as an effective sunscreen ingredient.MB is a century-old drug and experimental dye that has recently been shown to be the best antioxidant to combat ROS-induced cellular senescence in human skin.

It was hypothesized that the molecular structure and light-absorbing properties of this MB could be considered as an active sunscreen for UV radiation protection. In this study, the effect of MB on UVB radiation-induced DNA double-strand breaks in primary human keratinocytes was tested.

As a result, it was found that MB treatment reduced UVB radiation-induced DNA damage and subsequent cell death. MB was then compared to oxybenzone, the most commonly used chemically active ingredient in sunscreens, which has been proven to be harmful to coral reefs.

It was found that at the same concentration, MB showed a more effective UVB absorption capacity than oxybenzone, and significantly outperformed oxybenzone in preventing UVB-induced DNA damage and in clearing UVA-induced cellular ROS.

And, unlike oxybenzone, MB-containing seawater did not affect the growth of coral species, suggesting that MB is an active ingredient in reef-friendly sunscreens and has the potential to provide broad-spectrum protection against UVA and UVB.

We also did not find these limitations as a point of debate in the study, so we were hopeful that the product will be commercialized in the future.