Gut microbiota and eating behaviour in circadian syndrome.

Eating behaviour and circadian rhythms are closely related. The type, timing, and quantity of food consumed, and host circadian rhythms, directly influence the intestinal microbiota, which in turn impacts host circadian rhythms and regulates food intake beyond homeostatic eating. This Opinion discusses the impact of food intake and circadian disruptions induced by an obesogenic environment on gut-brain axis signalling.

Microbes, oxytocin and stress: Converging players regulating eating behavior.

Oxytocin is a peptide-hormone extensively studied for its multifaceted biological functions and has recently gained attention for its role in eating behavior, through its action as an anorexigenic neuropeptide. Moreover, the gut microbiota is involved in oxytocinergic signaling through the brain-gut axis, specifically in the regulation of social behavior. The gut microbiota is also implicated in appetite regulation and is postulated to play a role in central regulation of hedonic eating.

The oxytocin receptor represents a key hub in the GPCR heteroreceptor network: potential relevance for brain and behavior.

In the last 10 years, it has become increasingly clear that large numbers of axon collaterals extend from the oxytocin (OXT) hypothalamic axons, especially the parvocellular components, to other brain regions. Consequently, the OXT signaling system forms, like other monoamine axons, a rich functional network across several brain regions. In this manuscript, we review the recently indicated higher order G-protein coupled heteroreceptor complexes of the oxytocin receptor (OXTR), and how these, allosteric receptor-receptor interactions modulate the recognition, signaling, and trafficking of the participating receptor protomers and their potential impact for brain and behavior.

The microbiome-gut-brain axis in nutritional neuroscience.

Emerging evidence is highlighting the microbiome as a key regulator of the effect of nutrition on gut-brain axis signaling. Nevertheless, it is not yet clear whether the impact of nutrition is moderating the microbiota-gut-brain interaction or if diet has a mediating role on microbiota composition and function to influence central nervous system function, brain phenotypes and behavior. Mechanistic evidence from cell-based in vitro studies, animal models and preclinical intervention studies are linking the gut microbiota to the effects of diet on brain function, but they have had limited translation to human intervention studies.