Hepatic Lipid Catabolism via PPARα-Lysosomal Crosstalk

Int J Mol Sci. 2020 Mar 31;21(7):2391. doi: 10.3390/ijms21072391.

Abstract

Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors which belong to the nuclear hormone receptor superfamily. They regulate key aspects of energy metabolism within cells. Recently, PPARα has been implicated in the regulation of autophagy-lysosomal function, which plays a key role in cellular energy metabolism. PPARα transcriptionally upregulates several genes involved in the autophagy-lysosomal degradative pathway that participates in lipolysis of triglycerides within the hepatocytes. Interestingly, a reciprocal regulation of PPARα nuclear action by autophagy-lysosomal activity also exists with implications in lipid metabolism. This review succinctly discusses the unique relationship between PPARα nuclear action and lysosomal activity and explores its impact on hepatic lipid homeostasis under pathological conditions such as non-alcoholic fatty liver disease (NAFLD).

Keywords: NAFLD; NCoR1; PGC1α; PPARs; autophagy; lipophagy; lysosomes; peroxisomes.

Publication types

  • Review

MeSH terms

  • Animals
  • Autophagy / genetics
  • Cell Nucleus / metabolism
  • Gene Expression Regulation
  • Hepatocytes / metabolism
  • Humans
  • Lipolysis / physiology*
  • Liver / metabolism*
  • Lysosomes / genetics
  • Lysosomes / metabolism*
  • Non-alcoholic Fatty Liver Disease / metabolism
  • Nuclear Receptor Co-Repressor 1 / metabolism
  • PPAR alpha / metabolism*
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha / metabolism
  • Receptors, Cytoplasmic and Nuclear / metabolism
  • Triglycerides / metabolism

Substances

  • NCOR1 protein, human
  • Nuclear Receptor Co-Repressor 1
  • PPAR alpha
  • PPARA protein, human
  • PPARGC1A protein, human
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • Receptors, Cytoplasmic and Nuclear
  • Triglycerides