Host microbiota modulates development of social preference in mice

Area of Science:

• Neuroscience
• Microbiology
• Behavioral Science

Background:

• The gut microbiota plays a crucial role in programming brain function and behavior.
• Understanding the gut-brain axis is vital for comprehending neurodevelopmental processes.

Purpose of the Study:

• To investigate the impact of the indigenous gut microbiota on social preference and repetitive behaviors in germ-free (GF) mice.
• To analyze gene expression changes in the amygdala, a key social brain region, in GF versus conventionally raised (SPF) mice.

Main Methods:

• Utilized the germ-free (GF) mouse model, completely devoid of microbiota.
• Employed the three-chambered social approach task to assess social preference.
• Conducted real-time PCR to analyze gene expression of brain-derived neurotrophic factor (BDNF) and NGFI-A in the amygdala.

Main Results:

• GF mice exhibited significantly increased interaction with novel mice compared to specific pathogen-free (SPF) mice.
• No significant difference in repetitive self-grooming behavior was observed between GF and SPF mice.
• GF mice showed reduced mRNA levels of total BDNF, specific BDNF exons, and NGFI-A in the amygdala compared to SPF mice.

Conclusions:

• Indigenous gut microbes may differentially regulate BDNF exon transcripts in the amygdala.
• These microbial-driven changes in the amygdala could contribute to altered social development in germ-free mice.