Bioenergetics for Hepatocyte Polarization: Coordination of Multiple Cellular Organelles and the Master Regulator AMPK.

Abstract

Hepatocytes have well-defined polarized morphological structure. Establishment and maintenance of cellular polarity is crucial to the function and viability of hepatocytes. Many disorders, both genetic and acquired, and drugs can impair hepatocyte polarization resulting in liver dysfunction and injury. Hepatocyte polarization is an energy-dependent cellular process. Hence, cellular energy metabolism can significantly affect the polarized morphology and function of hepatocytes. Recent in vitro studies have demonstrated that multiple cellular organelles, including mitochondria, auto-phagosomes and lipid droplets, are involved in the utilization of energy for hepatocyte polarization; also, AMP-dependent kinase (AMPK), a key cellular energy sensor, regulates the function and activities of these cellular organelles and thus plays an important role in bioenergetics for hepatocyte polarization. This review provides the latest understanding on how mitochondria, autophagosomes, and lipid droplets coordinate energy production, and it addresses how AMPK activation regulates these key cellular organelles for energy production during hepatocyte polarization. Furthermore, the review suggests potential directions for future research.