Connecting link between Brain and Biome: unlocking psychobiotics

Microbes live all around and inside of us. More than a hundred trillion microbial cells live in just a human gut, outnumbering the total human cells by 10 fold-suggesting that gut is the major reservoir of microbes, more than any other organs in human body. One third of total microbes that live in the human gut are found to be similar across all individuals, but two third of gut microbes are specific to a particular individual. It's well known that gut microbiome is a key component of our immune system. Besides this, it also influences our mind by affecting hypothalamic-pituitary-adrenal (HPA)-axis in the brain, whose role is important in regulating the body's reaction to stress and many other processes including digestion, mood and emotion, sexuality and energy storage & expenditure. Researchers have also discovered that chronic hyper activation of the HPA axis can have knock-on effects for learning and memory, anxiety and depression, which are the major underlying symptoms for psychiatric illness. Increasing body of scientific evidences suggest that gut microbiome can communicate with the human brain through secretion of microbial metabolites (i.e., bile acid, short chain fatty acids and choline), or via immune activation (altering homeostasis of intestinal host-microbial interface) or via direct mechanism (i.e., release of neurometabolites/neurotransmitters). Gut dysbiosis (microbial imbalance) have also been shown to result in many nervous system disorders such as pain, autism and multiple sclerosis. Overall, this evidence reveals the importance of the gut microbiome on the gut-brain axis. During recent years, it has been shown that some probiotic bacteria may also be helpful in treating stress-related disorders and other mental related illness. These compelling evidences open up a new idea of 'psychobiotics'. According to Professor Ted Dinan at University College Cork, psychobiotics are live organism that, when ingested in adequate amounts, produces a health benefit in patients suffering from psychiatric illness. Therefore, understanding the real connections between brain and biome will help us in unlocking novel psycobiotics that are highly beneficial and can be supplement the use of anti-depressant to treat psychiatric illness. In conclusion, with those sights of promoting mental health, 'Prevention' is always better than 'Cure' protecting our gut health (maintaining microbial balance) from environmental factors such as antibiotics use, dietary intake of pesticides and chemical exposures can promote brain health.

International Behavioral Neuroscience Society (IBNS) News (July 2016, Editor Column) by Pushpanathan Muthuirulan (Guest Editor)

http://www.ibnsconnect.org/newsletter-vol20-4

(Picture has taken from Source: http://mindwellmed.com/psychobiotics-using-gut-bacteria-to-treat-mental-illness/)