Sibling factors associated with gut microbiota and fecal short-chain fatty acids in preschoolers
Year: 2026
Type: article
Abstract: BACKGROUND: Sibling factors are linked not only to disease development but also to gut environmental factors (e.g., microbiota, short-chain fatty acids [SCFA]). However, these associations among preschoolers and their underlying mechanisms remain unclear. METHODS: In a sub-cohort study of a nationwide birth-cohort study, using fecal microbiome and SCFA data from 903 children at age 2 or 4 years, we examined associations of sibling factors with gut environmental factors. We also determined enterotypes by clustering and sibling-enterotype associations with potential mediation pathways. RESULTS: Among sibling factors, the number of older siblings showed the strongest associations with gut environmental factors. We identified 3 enterotypes: 1) Mediterraneibacter gnavus group, 2) Faecalibacterium, and 3) Ruminococcus. Compared to enterotype 2, having older siblings was associated with lower odds of enterotype 1, with the lowest Shannon index and propionate level, at age 2 (1 sibling: adjOR 0.49, 95%CI 0.34-0.69; ≥2: adjOR 0.32, 95%CI, 0.19-0.54) and 4 (1 sibling: adjOR 0.45, 95%CI 0.26-0.77; ≥2: adjOR 0.22, 95%CI 0.08-0.53) years. These associations were largely direct, with modest mediation by antibiotic use at age 4 years (1 sibling, adjOR 0.89; 95%CI, 0.79-1.00). CONCLUSION: Our data identified distinct enterotypes of preschoolers and sibling-enterotype association pathways. IMPACT: In this nationwide multicenter birth-cohort sub-cohort, older siblings were strongly associated with gut microbial composition in preschoolers. Having older siblings was associated with lower odds of a potentially less mature enterotype characterized by the lowest Shannon index and propionate level. The sibling-enterotype association was mainly direct, with modest mediation by recent antibiotic use. This study extends sibling-microbiota evidence beyond infancy/toddlerhood by identifying three enterotypes with distinct microbial and short-chain fatty acid profiles. These findings clarify pathways linking family structure to gut environmental development and may inform microbiota-targeted disease prevention strategies.
Source: Pediatric Research
Authors: Yuichiro Tanaka, Ryohei Shibata, Yumiko Nakanishi, Tamotsu Kato, Bahrul Fikri, Tomoko Takahashi, Kenichi Sakurai, Midori Yamamoto, Masayuki Shima, Yasuhiro Takeshima, Narumi Tokuda, Taku Oishi, Narufumi Suganuma, Kahoko Yasumitsu-Lovell, Takahiro Arima, Hiroshi Kitazawa, Nobuo Yaegashi, Yuichi Adachi, Hidekuni Inadera, Shokei Murakami, Chisato Mori, Naoki Shimojo, Hiroshi Ohno
Institutions: Chiba University, National Center For Child Health and Development, RIKEN Center for Integrative Medical Sciences, Yokohama City University, Hasanuddin University, The University of Tokyo, Hyogo Medical University, University of Kochi, Kōchi University, Tohoku University, Tohoku Medical and Pharmaceutical University, University of Toyama, Yokohama City University Medical Center
Language: English
Topic: Gut microbiota and health
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $4,390
OpenAlex ID: W7221748266