Influence of gut microbiota on hepatic lipogenesis and disease pathogenesis

Liver, a major metabolic organ in the human body, plays a key role in the macronutrient metabolism. Accordingly, the liver is intertwined with an array of biochemical pathways that are central in keeping energy homeostasis. Loss of this delicate balance, however, may lead to a spectrum of liver diseases such as NAFLD, NASH, fibrosis, cirrhosis and HCC. The etiology of liver disorders is often multifactorial and greatly influenced by host genetics, diet and various environmental factors. Among the environmental factors, the gut microbiota has emerged as one of the key player that can profoundly influence host metabolism. Akin to a doubleedged sword, the gut microbiota and their metabolites exert both beneficial and deleterious extra-intestinal effects to the host. As a vascular firewall that receives 70 % of blood enriched with gut-derived factors via portal vein, the liver is thus aptly placed at the crossroad between host health and disease. In this chapter, we focus on the influence of gut microbiota and their metabolites in hepatic lipogenesis and disease pathogenesis.