Complex Adaptive BioSystems

Peptide-Based Therapies

Structure of PEPDEX

Bacteria and Immune System

Bacteria and Nervous System

The novel conceptual model “Brain-Gut Axis” has received emerging attention recently. Lots of studies showing evidence that intestinal microbiota have profound impacts on our nervous systems blossom during this 5~10 years. They interact with each other bidirectionally via various pathways. These include neuroendocrine (hypothalamus-pituitary-adrenal axis), immune systems (neuromodulating cytokines), enteric nervous systems and autonomic nervous systems (vagus nerve). Gut microbes produce substance such as tryptophan-related metabolites kynurenic acid, short chain fatty acids, and neurometabolites GABA, noradrenalin, and dopamine that potentially target to and influence functions of our central nervous systems. In the process of neurodevelopment, they modulate the expression level of many critical genes, such as brain-derived neurotropic factor (BDNF), NMDA receptors or 5-HT receptors and communicate with brain regions like striatum, hippocampus, amygdale, hypothalamus, and cingulated gyrus. It has long been known that the colonization of gut flora is related to the stress response of the hosts, changing their states of anxiety and exploratory behavior. Diseases such as inflammatory bowel diseases (IBS) and multiple sclerosis (MS) are also documented to be associated with intestinal microorganisms. New focus has been greatly put on many neuropsychiatric diseases, for instance, autism spectrum disorders (ASD), depression, anxiety disorders, and schizophrenia.

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