Anxiety and aggression associated with the fermentation of carbohydrates in the hindgut of rats

Fecal Fermentation in Irritable Bowel Syndrome: Influence of Dietary Restriction of Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols

“…However, we did not demonstrate a clear relation between SCFA levels and IBS symptoms. Previous investigations have evidenced a possible link between microbial fermentation products and abdominal complaints, as well as extra-intestinal symptoms, both in human studies [8,25,26] and in animal models [27,28]. The major SCFAs - acetic, propionic and n-butyric acids - have been particularly incriminated.…”

Metabolic tinkering by the gut microbiome

“…Using dietary manipulations that enhance gut microbial fiber fermentation in the cecum and colon, a positive correlation was observed between lactic acid and volatile fatty acid (VFA) production with anxiety-like behavior and aggression. 133 Subsequently, the same group demonstrated a positive correlation between serum lactate levels and the ability of rats to discriminate between a familiar and novel object, 134 suggesting improved cognitive performance. These results suggest that cognitive function may be modified by enhancing gut microbial fiber fermentation efficiencies.…”

Changes of the hindgut microbiota due to high-starch diet can be associated with behavioral stress response in horses

“…For instance, a reduced anxietylike behavior was observed in a spatial discrimination task in mice fed with a diet inducing a higher colonic bacterial diversity [15]. In addition, anxiety and aggression were increased following raised concentrations of fermentation end products, such as lactic acid and volatile fatty acids in the caecum of rats [16]. In humans, commensal microorganisms within the gut seem to play a role in determining stress reactivity especially through the hypothalamic-pituitary-adrenal axis [for a review 17].…”