PTPRK regulates glycolysis and de novo lipogenesis to promote hepatocyte metabolic reprogramming in obesity

Nat Commun. 2024 Nov 4;15(1):9522. doi: 10.1038/s41467-024-53733-0.

Abstract

Fat accumulation, de novo lipogenesis, and glycolysis are key drivers of hepatocyte reprogramming and the consequent metabolic dysfunction-associated steatotic liver disease (MASLD). Here we report that obesity leads to dysregulated expression of hepatic protein-tyrosine phosphatases (PTPs). PTPRK was found to be increased in steatotic hepatocytes in both humans and mice, and correlates positively with PPARγ-induced lipogenic signaling. High-fat-fed PTPRK knockout male and female mice have lower weight gain and reduced hepatic fat accumulation. Phosphoproteomic analysis in primary hepatocytes and hepatic metabolomics identified fructose-1,6-bisphosphatase 1 and glycolysis as PTPRK targets in metabolic reprogramming. Mechanistically, PTPRK-induced glycolysis enhances PPARγ and lipogenesis in hepatocytes. Silencing PTPRK in liver cancer cell lines reduces colony-forming capacity and high-fat-fed PTPRK knockout mice exposed to a hepatic carcinogen develop smaller tumours. Our study defines the role of PTPRK in the regulation of hepatic glycolysis, lipid metabolism, and tumour development in obesity.

MeSH terms

  • Animals
  • Diet, High-Fat / adverse effects
  • Fatty Liver / genetics
  • Fatty Liver / metabolism
  • Fatty Liver / pathology
  • Female
  • Glycolysis*
  • Hepatocytes* / metabolism
  • Humans
  • Lipid Metabolism
  • Lipogenesis* / genetics
  • Liver / metabolism
  • Liver / pathology
  • Liver Neoplasms / genetics
  • Liver Neoplasms / metabolism
  • Liver Neoplasms / pathology
  • Male
  • Metabolic Reprogramming
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout*
  • Obesity* / genetics
  • Obesity* / metabolism
  • PPAR gamma / genetics
  • PPAR gamma / metabolism
  • Receptor-Like Protein Tyrosine Phosphatases, Class 2* / genetics
  • Receptor-Like Protein Tyrosine Phosphatases, Class 2* / metabolism

Substances

  • Receptor-Like Protein Tyrosine Phosphatases, Class 2
  • PTPRK protein, human
  • PPAR gamma