Sex‐specific associations between gut microbiota and skeletal muscle mass in a population‐based study

Abstract

Abstract Background A gut–muscle axis through which the microbiome influences skeletal muscle has been hypothesized. However, sex‐specific association between the characteristics of gut microbiota and skeletal muscle mass has not yet been reported. Herein, we performed sex‐specific analyses of faecal microbiota composition for the skeletal muscle mass in a population‐based cohort. Methods We collected faecal samples of 1052 middle‐aged participants (621 men and 431 women) who attended health screenings, and we analysed the intestinal microbiota using 16S rRNA gene sequencing. Relative muscle mass was calculated using a bioelectrical impedance analysis and presented as the skeletal muscle mass index [SMI (%) = total appendicular muscle mass (kg)/weight (kg) × 100]. We categorized the subjects into four groups by the quartile of the SMI. Association tests between gut microbiota and SMI were conducted according to the microbial diversity, taxonomic profiling and functional inference in a sex‐stratified manner. Results The mean age and SMI of the total participants were 44.8 years (standard deviation [SD], 8.2) and 41.4% (SD, 3.9), respectively. After adjustments for possible covariates such as age, body mass index and regular physical activity, the highest quartile (Q4) group of SMI had higher alpha diversity than the lowest quartile (Q1) group in male participants (coefficient = 10.79, P 0.05). Conclusions In this large sample of middle‐aged individuals, this study highlights fundamental sex‐specific differences in the microbial diversity, composition and metabolic pathways inferred from gut microbiota according to SMI. The gut microbiota may provide novel insights into the potential mechanisms underlying the sex dependence of skeletal muscle mass.

Keywords

• gut microbiome
• microbiota
• sarcopenia
• skeletal muscle mass