A new investigation found that bacteria that live on our skin can act as a natural sunscreen.
Scientists have long recognized before human as a vibrant ecosystem that houses Millions of microorganisms.
Our skin microbiome includes bacteria, fungi and viruses. All play a fundamental role in the formation of our health, promoting skin immunity and protecting it against disease.
These friends friends feed on the nutrients of our skin and, as a byproduct, produce various active molecules that influence and interact with the cells of our skin.
Now, a study recently in the Journal of Investigative Dermatology described as certain Bacteria that live on our skin can act as a natural sunscreenhelping us to protect us from the ultraviolet (UV) rays of the sun.
According to the new investigation, these microbes can neutralize the UV -induced immune changeshelping the body’s natural defenses against the harmful effects of sunlight.
As details A, the study focused on the way skin microbes respond to UVB (type B ultraviolet) radiation, which causes sunburn. The team specifically studied these effects on the skin of the rats.
To begin with, the investigators tried to imitate sun exposure by scraping the dorsal skin of the rats and applying cis-urinic acid (dissolved in water). This acid is formed when the UV light collides with the outermost layer molecules of the skin. In addition, it can suppress the skin’s immunity responses, trigger inflammation and make the skin more vulnerable to skin cancer.
A natural “sunscreen”
The researchers found that specific bacteria, present in both human and mouse skin, when exposed to UV light, began to produce an enzyme called urocanase.
Scientists show that bacteria such as Staphylococcus epidermidis -a gram-positive bacteria that is part of the normal human microbiota-can use a part of this molecule as nutrient source.
However, the study also warns that the accumulation of cis-urine acid in healthy skin also acts as immunosuppressor.
“We have long known that UV radiation modulates immune responses directed against environmental antigen on the skin surface and, more recently, that skin microbiome also plays a role in regulating these answers,” says the main author, Vijaykumar patraquoted by New Atlas.
“What intrigued us was the idea that certain microbes could be actively involved or even interfere with the effects of UV rays. The overlap between microbial metabolism and host immunity became the focus of our investigation, ”he praised.
