Facial Skin Microbiome Composition and Functional Shift with Aging.

Area of Science:

• Microbiology
• Dermatology
• Aging Research

Background:

• The aging process significantly impacts the human skin microbiome, but comprehensive understanding remains limited.
• Skin microbiome composition and function are crucial for maintaining skin health and barrier integrity.
• Age-related changes in the skin microbiome may influence skin aging and susceptibility to conditions.

Purpose of the Study:

• To investigate age-related alterations in the facial skin microbiome composition and function.
• To compare the skin microbiota between younger (18-35 years) and older (≥55 years) female volunteers.
• To identify specific bacterial taxa and functional gene pathways associated with skin aging.

Main Methods:

• Whole-genome sequencing of facial skin swabs from 100 healthy Caucasian female volunteers.
• Volunteers were categorized into two age groups (18-35 and ≥55 years) and by wrinkle grade.
• Microbiome composition analyzed using taxonomic and non-metric multidimensional scaling; functional analysis via Gene Ontology (GO) terms.

Main Results:

• The skin microbiome was significantly more diverse in the older age group (≥55 years).
• Older adults showed decreased Actinobacteria (specifically Cutibacterium acnes) and increased Corynebacterium kroppenstedtii.
• Younger adults (18-35 years) had higher proportions of Cutibacterium acnes and Lactobacillus (notably Lactobacillus crispatus), with enhanced gene expression in metabolic and protective pathways.

Conclusions:

• Aging leads to distinct shifts in facial skin microbiome diversity and composition, with specific bacterial taxa changes.
• Younger skin microbiomes are characterized by higher Cutibacterium acnes and Lactobacillus, and enhanced protective functions.
• Understanding these age-related microbiome changes provides a foundation for exploring their role in skin aging and anti-aging strategies.