The gastrointestinal tract plays an important role in maintaining of our various physiological functions. Although the gastrointestinal tract is inside of our body, it is the "outside world”. In fact, large number of bacteria coexist and are involved in maintaining of mucosal function. Unbalanced diet, several drugs, decreased blood flow, stress may cause the damage of this balance. Once the balance is destroyed, dysfunction of mucosa and increased permeability are induced. Such excessively increased permeability of intestinal mucosa is defined as “Leaky gut syndrome (LGS)”, and various large-molecular weighted substances are transferred into the blood circulation. The LGS is considered to be a trigger for various systemic diseases such as non-alcoholic steatohepatitis (NASH), inflammatory bowel disease, cardiovascular diseases, allergy, chronic kidney disease, etc.
In this presentation, we show the outline of various systemic diseases caused by LGS, especially focused on multi-organ relationships such as "Gut-liver axis" and "Oral-gut axis". In addition, we show the effect of improving LGS status on various systemic diseases and the possibility of LGS as a target for new drug discovery.