Mendelian randomization analysis reveals causal relationships between gut microbiome and optic neuritis

Area of Science:

• Microbiome research
• Neuroimmunology
• Ophthalmology

Background:

• The relationship between gut microbiota (GM) and optic neuritis (ON) risk is not fully understood.
• Potential pathways include the
• gut-brain
• and
• gut-retina
• axes.

Purpose of the Study:

• To investigate the potential causal relationship between gut microbiota composition and the risk of developing optic neuritis.
• To explore the role of the gut-brain and gut-retina axes in this association.

Main Methods:

• A Mendelian randomization (MR) study was conducted using genome-wide association study (GWAS) data from up to 18,340 samples across 24 cohorts for 196 gut microbiota taxa.
• Optic neuritis outcomes were analyzed using GWAS data from FinnGen and UK Biobank.

Main Results:

• Specific gut bacteria, including Family -Peptococcaceae, Genus- Hungatella, and Genus- Eubacterium_rectale_group, were found to be associated with ON risk in the FinnGen cohort.
• Genus- Eubacterium_hallii_group and Genus- Ruminococcaceae_UCG_002 showed correlations with ON risk in the UK Biobank data.
• No causal relationships were identified at the phylum, class, or order levels of gut microbiota.

Conclusions:

• The MR findings suggest a causal effect of certain gut microbiota taxa on optic neuritis risk.
• Gut microbiota may influence optic neuritis through the gut-brain and gut-retina axes.
• Further investigation is required to elucidate the precise mechanisms underlying the gut microbiota-optic neuritis relationship.