Breaking fat: The regulation and mechanisms of lipophagy

Lipophagy is defined as the autophagic degradation of intracellular lipid droplets (LDs). While the field of lipophagy research is relatively young, an expansion of research in this area over the past several years has greatly advanced our understanding of lipophagy. Since its original characterization in fasted liver, the contribution of lipophagy is now recognized in various organisms, cell types, metabolic states and disease models. Moreover, recent studies provide exciting new insights into the underlying mechanisms of lipophagy induction as well as the consequences of lipophagy on cell metabolism and signaling. This review summarizes recent work focusing on LDs and lipophagy as well as highlighting challenges and future directions of research as our understanding of lipophagy continues to grow and evolve. This article is part of a Special Issue entitled: Recent Advances in Lipid Droplet Biology edited by Rosalind Coleman and Matthijs Hesselink. •Lipophagy contributes to lipid droplet (LD) degradation in numerous cell types.•Perilipins, lipases, and Rab GTPases act as key regulators of autophagic/lipophagic initiation.•Alterations in lipophagy are common in various diseases.•The mechanisms whereby autophagic machinery target LDs is poorly understood.•The downstream effects of lipophagy on cell signaling networks are largely unknown.