**6. Conclusions**

The effect of the probiotics on the intestinal microbiota is quite important not only for the functions on intestine, but also for the development and function of immune system, metabolism, and central nervous system. Moreover, these systems are closely related, so that any alteration will impact their functionality. Therefore, the balance on microbiota-gut-central nervous system axis is very important to maintain the adequate functions of these systems.

Intestinal dysbiosis leads to alterations in development and function of central nervous system, which is significantly improved upon intestinal colonization with normal microbiota and probiotics treatment. To date, the interaction of microbiotaintestine-brain axis is not completely clear. For this reason, it is interesting to redirect the investigation of CNS diseases whose pathological mechanism is unknown.
