Fig. 2: Dynamic processes in LDs breakdown.
From: Are lipid droplets the picnic basket of brain tumours?
LDs breakdown is orchestrated through two primary mechanisms: lipolysis and lipophagy. A Schematic illustration delineating TAG intracellular lipolysis. This process unfolds in a sequential cascade involving adipose triglyceride lipase (ATGL), hormone-sensitive lipase (HSL), and monoacylglycerol lipase (MAGL), all situated on the LDs surface. ATGL initiates the process, catalyzing the conversion of triacylglycerols (TAGs) into diacylglycerol (DAG) and fatty acids (FAs). Subsequently, HSL further breaks down DAG into monoacylglycerol (MAG) and FAs. Finally, MAGL liberates FAs and glycerol. The lipolytic products, including DAG, MAG, FAs, and glycerol, serve as energy resources, membrane biosynthesis and others. B Lipophagy, an intricately regulated form of autophagy, engages the encapsulation of lipid droplets within autophagosomal membranes. These engulfed droplets are subsequently transported to lysosomes, where degradation occurs through acid lipolysis. Lysosomal TAG lipolysis is orchestrated by lysosomal acid lipase (LAL). Figure crafted using BioRender.com.
