Aged related human skin microbiome and mycobiome in Korean women

Abstract

We examined differences in the skin microbiome of two separate age groups to find key microbial and skin physiological indicators associated with aging. We recruited healthy Korean women 19–28 years old (Y-group) and 60–63 years old (O-group) and evaluated their cheek and forehead skin microbiome, including bacteria and fungi. The microbiome was significantly different by age group, with bacterial and fungal communities displaying higher alpha-diversity in the O-group than in the Y-group. We identified amplicon sequence variants affiliated with Cutibacterium and Lactobacillus and fungi Malassezia restricta as microbial biomarkers showing significant differences between the Y and O-group. There are more microbial communities and metabolic processes related to skin health in the Y-group than in the O-group, and there are more microbial interactions to increase the stability of the network structure of the skin. Skin physical metadata, including transepidermal water loss and sebum content, differed by two age groups. The crucial skin microbes, skin physical parameters, and microbial network found through this research will be useful key indicators in associating skin aging and skin microbiome research.

The Skin Microbiome: Current Landscape and Future Opportunities

“…As intrinsic ageing underpins both types of ageing, these results suggest that microbial diversity is highly dictated by intrinsic ageing mechanisms. This has been corroborated in other studies in women, with the within-sample microbial diversity of aged skin being significantly higher than that in young adult skin and most significant in sun-protected sites [ 9 , 104 , 108 , 141 ]. Overall abundance of bacteria increases with age, but this is not directly proportional as certain bacteria become more dominant (e.g., Corynebacterium ) while others decline in number (e.g., Cutibacterium and Lactobacillus [ 9 , 104 , 108 , 141 ]) in a site-independent manner.…”

“…This has been corroborated in other studies in women, with the within-sample microbial diversity of aged skin being significantly higher than that in young adult skin and most significant in sun-protected sites [ 9 , 104 , 108 , 141 ]. Overall abundance of bacteria increases with age, but this is not directly proportional as certain bacteria become more dominant (e.g., Corynebacterium ) while others decline in number (e.g., Cutibacterium and Lactobacillus [ 9 , 104 , 108 , 141 ]) in a site-independent manner. Certain genera are also altered by body site, such as higher abundance of Streptococcus and lower abundance of Staphylococcus on the buttocks [ 9 ].…”

“…The inherent high complexity and variability of the skin microbiome makes it challenging to delineate its role in specific physiological processes [ 102 ]. Despite this, several pertinent studies have shed light on how the skin microbiota change throughout the life course [ 103 , 104 , 105 ], and how perturbations in microbial composition are associated with skin disease and ageing [ 106 , 107 , 108 ].…”

“…These shifts in microbial composition coincide with physical changes in the skin, as the skin of infants is thinner, more alkaline and has a higher cell turnover rate compared to adults [ 132 , 133 , 134 ]. It is therefore not surprising that naturally aged skin, featuring many physiological and structural modifications, exhibits drastic compositional alterations in the skin microbiome [ 76 , 104 , 105 , 134 ].…”

Skin microbiome attributes associate with biophysical skin aging

“…On one hand, confounding factors such as sex, ethnicity, geography, and health condition can all affect skin microbiome 18 , which increase data dimensionality and decrease statistical power 7 . On the other hand, while previous investigations revealed aging-related skin microbiome changes at phylum-to genus-resolution 11,[14][15][16][17][18] , studies by our group and others have shown that the aging-related diversity of the skin microbiome is often manifested at species-, strain-, or genelevel 7 . Moreover, such high-resolution diversity has potential health implications.…”