Microbiome in aging of Gut and Brain (MiaGB): paving the ways to understand gut-brain axis in aging.

Decades of aging research established several well-characterized theories of aging, yet as the studies often focus on different cellular mechanisms there is overall agreement that organismal aging is characterized by multi-factorial degenerative processes resulting from multiple alterations of different molecular pathways compromising cellular or tissues functions. Due to this complexity aging is a major risk factor for multiple diseases including cardiovascular diseases, cancers, diabetes, and neurological diseases such as Alzheimer's disease. It is well known that this multi-factorial process in some cases might be accelerated by the dysfunction of one organ as a source of chronic low-grade inflammation. Importantly, most recent studies provide strong evidence that the gut microbiome represents a new independent organ system mainly composed of a variety of microorganisms recognized as the microbiome. The high integrity of the microbiome with the host physiology and biochemical interactions between specific bacteria and cellular processes supports its organ-like function in organismal health and the process of aging. However, it is important to better understand what causes potential cellular stress to accelerate a variety of pathological changes, what is the specific role of our gut microbiome in process of human aging, and how we could use this knowledge to prevent or delay aging pathology.