Does the skin microbiome contribute to protection from long-term sun damage?

A recent study published in Environmental research The journal examined how the skin microbiome contributes to protection against sun damage when exposed to sunlight daily.study: Skin Microbiome Bacteria Enriched After Prolonged Sun Exposure Can Reduce Oxidative Damage: A 5-Month Preliminary Study of 10 Lifeguards. Image Credit: ART-ur/Shutterstock.com

Background

The skin microbiome helps protect the skin from infection and acts as a natural and effective barrier against pathogens present in the environment.

Exposure to solar radiation increases the risk of skin cancer and can accelerate skin aging. A new paper investigates the role of skin bacteria in protecting lifeguards, who are typically exposed to the sun for long periods of time during the day, from sun damage.

prologue

The human microbiome is essential in maintaining the health of the human organism through mutualistic interactions between hosts and microbes.

The skin microbiome (SMB) prevents overgrowth by pathogenic species by both competing for suitable space and producing inhibitory antimicrobial peptides (AMPs).

However, there are nuances in the overall relationship between the microbiome and host, and even specific strains of the same microbe can have beneficial or detrimental effects on the skin in the right mix of circumstances. , which may affect barrier function.

Exposure to ultraviolet radiation (UVR) is harmful to the skin and its resident microbes. UVR causes deoxyribonucleic acid (DNA) damage, which can lead to fatal cancerous changes in the host in the long term.

Generation of reactive oxygen species (ROS) is one important indirect method of UVR-induced skin damage.

Natural defenses against such damage include skin pigmentation, DNA repair pathways, antioxidant molecules, and may be combined with the actions of certain components of SMB.

For example, cyanobacteria produce cytonemine, a bioactive pigment that can block UVR in prokaryotes without degrading in the presence of sunlight.

It is known that SMB does not change substantially when exposed to stressors. In the current paper, we focused on specific species changes that are low in abundance but have a significant impact on host–microbiome interactions in response to UVR exposure.

When these are concentrated after sun exposure, they are UVR stable, indicating that they may be able to protect the skin from UVR-related damage.

What did the research show?

Skin swabs were obtained from 10 lifeguards before and after summer. Both showed similar abundance of skin microbes, but we found that certain species that were less abundant showed greater variation. I understand.

Researchers found that in 10 lifeguards whose skin samples were examined before and after the onset of summer, certain species of bacteria were abundant after seasonal sun exposure.

These are included Sphingomonas and Erythrobacteraceae, two species that may be able to reduce the harmful effects of UV light. The former showed a high level of resistance to damage caused by 254 nm and 312 nm UVR, with exposures ranging from 8 to 20 mJ/sq. cm. and 122 to 366 mJ/sq. cm, respectively.

in the meantime Escherichia coli Sphingomonas mucosissima could not tolerate minimal amounts of radiation, whereas Sphingomonas mucosissima could tolerate all radiation doses, indicating high tolerance to UV irradiation.”

This occurs through the production of protective chemicals that limit human keratinocyte production. Such compounds include ubiquinone 10, glycosphingolipids (GSLs), and the yellow carotenoid pigment from increase. Sphingomonasand glucagon-like peptides (GLP) and carotenoids ErythrobacteraceaeCarotenoids are powerful antioxidants and GSL helps maintain the integrity of the skin barrier.

Increased abundance of these two taxa was seen in more than half of the swabs, indicating their ability to withstand UVR.

Of course, this property may also be shared by non-beneficial skin bacteria, but changes in skin hydration may explain other aspects of such changes.

in vitro Results showed that exposure to ultraviolet B (UVB) radiation caused a 3-fold increase in ROS levels, which was mitigated by adding antioxidants such as N-acetylcysteine.

A similar effect, resulting in a four-fold reduction in ROS levels, was also observed when cells were added to solutions containing lysates or culture supernatants. Sphingomonas not the culture Escherichia coli culture.

The lysate was potently protective at low concentrations, suggesting that this and other low-abundance bacteria may be important in preventing UVR-induced skin damage.

Thus, this study showed that bacterial species capable of protecting skin from the adverse effects of solar UVR increased after prolonged sun exposure, despite no significant changes in the overall composition of SMB. .

This confirms previous studies showing that SMB remains stable for 2 years for the most abundant species, but changes over time for less abundant species.

Again, previous studies Sphingomonas Inhibits cell aging and promotes skin reconstruction.

What is the impact?

These results suggest that members of the skin microbiome can enhance protection from solar radiation damage and contribute to human health.”

Larger studies involving other geographic and climatic settings, as well as other groups of people, may help identify bacteria and products that provide potent protection against solar radiation.