Sex- and brain region-specific alterations in brain volume in germ-free mice
Shawna L. Thompson,
Jacob Ellegood,
Dawn M.E. Bowdish,
Jason P. Lerch,
Jane A. Foster
Affiliations
Shawna L. Thompson
Psychiatry and Behavioural Neuroscience, McMaster University, Hamilton, ON, Canada; Corresponding author
Jacob Ellegood
Mouse Imaging Centre, The Hospital for Sick Children, Toronto, ON, Canada; Corresponding author
Dawn M.E. Bowdish
Department of Medicine and McMaster Immunology Research Centre, McMaster University, Hamilton, ON, Canada; Corresponding author
Jason P. Lerch
Mouse Imaging Centre, The Hospital for Sick Children, Toronto, ON, Canada; Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford UK; Corresponding author
Jane A. Foster
Psychiatry and Behavioural Neuroscience, McMaster University, Hamilton, ON, Canada; Research Institute at St. Joe’s Hamilton, Hamilton, ON Canada; Center for Depression Research and Clinical Care, Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA; Corresponding author
Summary: Several lines of evidence demonstrate that microbiota influence brain development. Using high-resolution ex vivo magnetic resonance imaging (MRI), this study examined the impact of microbiota status on brain volume and revealed microbiota-related differences that were sex and brain region dependent. Cortical and hippocampal regions demonstrate increased sensitivity to microbiota status during the first 5 weeks of postnatal life, effects that were greater in male germ-free mice. Conventionalization of germ-free mice at puberty did not normalize brain volume changes. These data add to the existing literature and highlight the need to focus more attention on early-life microbiota-brain axis mechanisms in order to understand the regulatory role of the microbiome in brain development.
