Happy Gut, Happy Brain? New Study in Chinese Medical Journal Explores Effects of Gut Flora on Mental Health

BEIJING, Feb. 3, 2022 /PRNewswire/ — Specialized cells in our gut called the enteroendocrine cells produce gut hormones that control our food intake and appetite. The gut-brain axis connects the central nervous system (CNS) and gastrointestinal tract; keeping this channel of communication alive is necessary to maintain a balance between various gut functions. The enteroendocrine hormones are often influenced by the gut microbiota—an ecosystem of microorganisms living in our gut. The hormones and the microbiota produce biochemical signals that enable a crosstalk between the cognitive and emotional centers of the brain and the intestinal functions. The microbiota and the related hormones also influence the development of digestive conditions like metabolic disturbances and inflammation disorders. Recent studies show that hormones in the gut-brain axis may even link back to neurological and psychological disorders.

In a recent paper published online on 5th April 2020 in the Chinese Medical Journal, a research team led by Dr. Yong-Zhan Nie dove into studies investigating interactions between gut hormones and microbiota and highlighted their role in development of physiological and psychological gut-brain axis associated disorders. As Dr. Nie explains, "Modern tools like sequencing technology and bioinformatics have opened new doors to the elusive world of microbiology and neuroscience, leading to some fascinating research exploring the effect our gut microbiology has on our brain. Our aim was to bring such original studies and reviews under one roof."

Gut hormones that relay hunger signals to the CNS often play a crucial role in the development of mood disorders and obesity. For instance, ghrelin, a neuroactive gut hormone that activates food craving, also regulates stress response, depression, and anxiety. Studies show that a reduction in ghrelin concentration in our body reduces anxiety levels and also the urge to eat high-calorie foods.

It has also been found that the gut microbiomes often secrete neuroactive chemicals that can mimic "neurotransmitters" produced by nerve cells and influence the brain functions. An imbalance in gut microbiota can have an effect on neurological disorders like epilepsy, autism, and Parkinson’s disease.

Several studies have attempted to decipher the communication pathways between gut hormones and the microbiota. Current evidence suggests that the gut microbiota might indirectly interact with the host hormones via metabolism and immunity functions controlled by the CNS and gastrointestinal tract.

"Our overview can help scientists further explore the relationship between microbiota-hormones-gut brain axis and develop novel therapeutics for different psychiatric and gastrointestinal disorders, such as obesity, anxiety, and depression," concludes Dr. Nie.

Title of original paper: Gut hormones in microbiota-gut-brain cross-talk

Journal: Chinese Medical Journal

DOI: https://doi.org/10.1097/CM9.0000000000000706

Peifang Wei


SOURCE Chinese Medical Journal