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Updated: Jan 1, 2026
10:28
Imaging Mismatch Repair and Cellular Responses to DNA Damage in Bacillus subtilis
Published on: February 8, 2010
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Intestinal bacterial indicator phylotypes associate with impaired DNA double-stranded break sensors but augmented
Irene Maier1, Jared Liu1, Paul M Ruegger2
1Department of Environmental Health Sciences, Fielding School of Public Health, University of California, Los Angeles 650 Charles E. Young Dr. South, Los Angeles, CA, USA.
Carcinogenesis
|December 17, 2019
Summary
Microbiota restriction in mice altered gut bacteria, impacting radiation genotoxicity and immune responses. Female mice with restricted microbiota showed improved bone structure and reduced inflammation post-radiation.
Area of Science:
- Microbiology
- Radiation Biology
- Immunology
Background:
- Intestinal microbiota influence host energy balance, immunity, and regeneration.
- Previous work linked microbiota restriction to increased radiation genotoxicity and immune cell activation.
Purpose of the Study:
- Investigate the correlation between specific gut bacterial communities and radiation-induced genotoxicity.
- Examine the impact of microbiota restriction on immune responses and tissue regeneration following particle radiation exposure.
Main Methods:
- Comparison of gut microbiota composition in restricted microbiota (RM) and conventional microbiota (CM) mice.
- Analysis of systemic genotoxicity, lymphocyte activation, and metabolic pathway polarization post-irradiation.
- Assessment of cytokine expression (interferon-γ, transforming growth factor-β, interleukin-17) and bone micro-architecture.
Main Results:
- RM mice exhibited altered bacterial abundance, including increased Lactobacillus johnsonii.
- *Muribaculum intestinale* and *Helicobacter rodentium* were associated with radiation resistance in CM mice.
- Female RM mice demonstrated improved bone structure and anti-inflammatory responses 6 weeks post-radiation, with reduced tumor necrosis factor markers.
Conclusions:
- Gut microbiota composition significantly modulates systemic responses to radiation.
- Specific bacterial phylotypes in RM mice correlate with differential genotoxicity and immune profiles.
- Microbiota restriction may offer protective effects against radiation-induced damage, particularly in females.
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