Vitamin B-6 Deficiency Induces Anxiety-Like Behavior in Sprague-Dawley Rats by Disrupting Gut Homeostasis

Area of Science:

• Neuroscience
• Microbiology
• Nutritional Science

Background:

• Vitamin B-6 (VB-6) is crucial for metabolic pathways, including neurotransmitter synthesis, with deficiency linked to neurological issues.
• Emerging research suggests B vitamin deficiencies can disrupt the gut microbiome, yet the gut-brain axis's VB-6-mediated mechanisms remain unclear.

Purpose of the Study:

• To investigate the role of VB-6 in modulating the gut-brain axis.
• To determine the impact of VB-6 deficiency on neurobehavioral outcomes via gut-mediated pathways.

Main Methods:

• Sixty-four rats were fed diets with optimal or deficient VB-6 for 7 weeks, with some receiving antibiotics.
• Assessed plasma VB-6, neurotransmitters, short-chain fatty acids (SCFAs), behavior, gut microbiome composition, and gut histology.

Main Results:

• VB-6 deficiency drastically reduced plasma VB-6, altered brain neurotransmitters (GABA, glutamic acid), and induced anxiety-like behaviors.
• Significant shifts in gut microbiota composition, including increases in Lachnospiraceae and Mucispirillum and decreases in Muribaculaceae and Bacteroides, were observed.
• Cecal SCFA concentrations declined, with specific reductions in propionate, isobutyrate, and isovalerate, correlating with neurochemical and behavioral changes.

Conclusions:

• Vitamin B-6 deficiency profoundly impacts gut microbiota, SCFA production, and neurotransmitter balance, ultimately causing anxiety-like behaviors.
• The gut microbiota plays a critical role in mediating the effects of VB-6 on the gut-brain axis.