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Sex differences and hormonal effects on gut microbiota composition in mice
Elin Org1,2, Margarete Mehrabian1, Brian W Parks1,3
1a Department of Medicine/Division of Cardiology , David Geffen School of Medicine, University of California , Los Angeles , CA , USA.
Gut Microbes
|June 30, 2016
Summary
Sex differences in gut microbiota are influenced by host genetics and diet. Gonadectomy and hormone replacement significantly alter microbiota composition, with bile acids potentially mediating these changes.
Area of Science:
- Microbiology
- Genetics
- Animal Science
Background:
- Gut microbiota composition varies significantly across different inbred mouse strains.
- Previous research quantified gut microbiota in 89 mouse strains, establishing a baseline for further investigation.
Purpose of the Study:
- To investigate sex differences in gut microbiota composition.
- To explore the influence of host genetics, diet, and hormones on these sex differences.
Main Methods:
- Analysis of gut microbiota composition in 689 mice across 89 inbred strains.
- Examination of microbiota in mice on chow and high-fat diets.
- Investigation using gonadectomized and hormone-treated mice from three inbred strains.
- Principal coordinate analysis with unweighted UniFrac distances.
- Bile acid analyses.
Main Results:
- Overall sex differences in microbiota were observed, but more pronounced differences emerged at the single-strain level, indicating host genetics can mask sex effects.
- Significant sex-by-diet interactions were identified in mice on different diets.
- Gonadectomy and hormone replacement profoundly impacted microbiota composition across all three tested strains.
- Bile acid profiles showed gender-specific differences and were affected by gonadectomy, suggesting a mechanistic link.
Conclusions:
- Sex differences in gut microbiota are complex and modulated by host genetics, environmental factors like diet, and hormonal status.
- Hormonal regulation, potentially via bile acid pathways, plays a critical role in shaping sex-specific gut microbial communities.
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