What is the Origin of Gut-Liver-Brain Axis?

This conceptual framework is an expansion of the well-established Gut-Brain Axis, incorporating the liver as a central metabolic and detoxification hub. The term axis signifies a system of mutual, reciprocal influence between the three organs. Its recognition reflects a growing understanding in endocrinology and gastroenterology that systemic health is a product of interconnected organ function.

What is the Mechanism of Gut-Liver-Brain Axis?

Communication along the axis occurs through multiple channels, including the vagus nerve, circulating gut hormones like GLP-1 and PYY, and microbial metabolites such as short-chain fatty acids (SCFAs). The gut microbiota influences liver function by modulating portal vein exposure to bacterial products, while the liver processes nutrients and toxins, generating signals that affect brain function and appetite. The brain, in turn, influences gut motility and liver metabolism via the autonomic nervous system and HPA axis hormones, completing the complex feedback loop.

Gut-Liver-Brain Axis

Meaning

A complex, bidirectional communication network that functionally links the gastrointestinal tract, the liver, and the central nervous system, playing a fundamental role in metabolic, hormonal, and cognitive regulation. This axis integrates signals from the gut microbiota, gut hormones, nutrient metabolism, and neuroendocrine pathways to maintain systemic homeostasis. Dysregulation of this intricate system is increasingly implicated in a range of metabolic and neurodegenerative disorders.