Neutrophils in Non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are prevalent chronic liver conditions worldwide. Despite recognition as key players in the inflammatory process of NAFLD, the specific role of Neutrophils in liver-lipid accumulation and progression of NAFLD has remained largely unexplored. In this study, we explored the involvement of neutrophils in the early stages of NAFLD and their contribution to hepatic lipid buildup. Our investigation uncovered a crucial function of neutrophils: they uptake extracellular fatty acids and lipids released from adipocytes, and store them as triglycerides within lipid droplets. Significantly, these lipid-laden neutrophils do not utilize the stored lipids for energy or functions. Instead, they act as carriers, transporting these stored lipids to hepatocytes via extracellular vesicles (EVs). Remarkably, these neutrophil-derived EVs also contain microRNAs (miRNAs) that modulate genes involved in lipid metabolism. These action results in the accumulation of triglycerides (TGs) within hepatocytes.