Probiotics and Gastrointestinal Health : Mechanism of Gastrointestinal Immunomodulation and Neuromodulation

The microbial population in the gastrointestinal tract is well known as gastrointestinal microbiota. The gastrointestinal tract contains 3.8×10¹³ microbes whose main activities are completed in this part. The probiotic bacteria are the family of gastrointestinal microbiota which is administrated orally from the external environment by the foods. Probiotics have various functional activities in the gastrointestinal tract. For digestion and absorption of undigested long-chain polysaccharides, probiotics help to increase the prebiotic bacterial ecosystem in the gastrointestinal tract. Whose main activity is to ferment those foods and produce short-change fatty acids which have a positive impact on the proliferation of epithelial cells and pancreatic secretion. By the production of interleukin-10 and interleukin-12, probiotics prevent damage to the intestinal host cell, reduce inflammation and limit the host immune response. These have a functional activity on modulation of immune cell function and inducing the hyporesponsiveness of T cells and B cells. In this way, probiotic bacteria can apply immunomodulation activity to the gastrointestinal tract. The neural interaction between the gastrointestinal tract and central nervous system is sometimes maintained by the probiotic bacteria. Probiotics help submit and transmit the neural signals between the gastrointestinal tract and central nervous system. Various evidence demonstrated that probiotics may reduce anxiety and depression behaviour and also it improves brain function. In this review, we tried to discuss about gastrointestinal health, related to immunomodulatory and neuromodulatory functions by the activity of life-saving medicine probiotics.