Reference Number: 86
The gut-brain-axis refers to the bidirectional communication between the enteric nervous system and the central nervous system. Mounting evidence supports the premise that the intestinal microbiota plays a pivotal role in its function and has led to the more common and perhaps more accurate term gut-microbiota-brain axis. Numerous studies have identified associations between an altered microbiome and neuroimmune and neuroinflammatory diseases. In most cases, it is unknown if these associations are cause or effect; notwithstanding, maintaining or restoring homeostasis of the microbiota may represent future opportunities when treating or preventing these diseases. In recent years, several studies have identified the diet as a primary contributing factor in shaping the composition of the gut microbiota, and in turn, the mucosal and systemic immune systems. In this review, we will discuss the potential opportunities and challenges with respect to modifying and shaping the microbiota through diet and nutrition in order to treat or prevent neuroimmune and neuroinflammatory disease.
SIGNIFICANCE OF THIS STUDY
Most neuroimmune diseases are characterized by a spectrum of symptoms and the pathophysiology of these diseases cannot typically be defined by an individual organ or system (such as neurological); instead, a more systemic point of view must be considered. Indeed, it is increasingly evident that the gut microbiota dramatically influences systemic immunity, including the host’s neuroimmune status, both beneficially and adversely. The so-called “gut-microbiota-brain” axis dictates that biochemical signaling occurs between the enteric nervous system (ENS) of the GI tract and the central nervous system (CNS) and principally involves the intestinal microbiota. This signaling can occur directly via the vagus nerve or indirectly, through chemical signals that are released into the periphery and act in an endocrine manner. When an imbalance of the gut microbiota occurs and results in an increase in noncommensal microbes (dysbiosis), homeostasis of the gut microbiota is disrupted. Signaling between the gut-brain axis is also impacted, potentially leading to neurological and neuroimmune abnormalities. Numerous studies have now identified alterations in the gut microbiota in a wide range of neuroimmune diseases, although, in most instances, it has yet to be determined if the aberrant microbiota contributes to the disease or is a result of the disease. As evidence mounts connecting the gut microbiota to neuroimmune and neuroinflammatory disease, the possibility for altering the microbiota as a treatment strategy is a logical progression in an age of translational medicine.