A Combined Model of Human iPSC-Derived Liver Organoids and Hepatocytes Reveals Ferroptosis in DGUOK Mutant mtDNA Depletion Syndrome

Adv Sci (Weinh). 2021 Mar 8;8(10):2004680. doi: 10.1002/advs.202004680. eCollection 2021 May.

Abstract

Mitochondrial DNA depletion syndrome (MDS) is a group of severe inherited disorders caused by mutations in genes, such as deoxyribonucleoside kinase (DGUOK). A great majority of DGUOK mutant MDS patients develop iron overload progressing to severe liver failure. However, the pathological mechanisms connecting iron overload and hepatic damage remains uncovered. Here, two patients' skin fibroblasts are reprogrammed to induced pluripotent stem cells (iPSCs) and then corrected by CRISPR/Cas9. Patient-specific iPSCs and corrected iPSCs-derived high purity hepatocyte organoids (iHep-Orgs) and hepatocyte-like cells (iHep) are generated as cellular models for studying hepatic pathology. DGUOK mutant iHep and iHep-Orgs, but not control and corrected one, are more sensitive to iron overload-induced ferroptosis, which can be rescued by N-Acetylcysteine (NAC). Mechanically, this ferroptosis is a process mediated by nuclear receptor co-activator 4 (NCOA4)-dependent degradation of ferritin in lysosome and cellular labile iron release. This study reveals the underlying pathological mechanisms and the viable therapeutic strategies of this syndrome, and is the first pure iHep-Orgs model in hereditary liver diseases.

Keywords: N‐acetylcysteine; ferroptosis; induced pluripotent stem cells; mitochondria; mitochondrial DNA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA, Mitochondrial / genetics
  • Ferritins / metabolism
  • Ferroptosis
  • Fibroblasts / metabolism
  • Fibroblasts / pathology
  • Humans
  • Induced Pluripotent Stem Cells / metabolism
  • Induced Pluripotent Stem Cells / pathology*
  • Iron Overload / physiopathology
  • Liver / metabolism
  • Liver / pathology
  • Liver Failure / genetics
  • Liver Failure / metabolism
  • Liver Failure / pathology*
  • Lysosomes / metabolism
  • Mitochondrial Diseases / genetics
  • Mitochondrial Diseases / metabolism
  • Mitochondrial Diseases / pathology*
  • Mutation*
  • Nuclear Receptor Coactivators / genetics
  • Nuclear Receptor Coactivators / metabolism
  • Organoids / metabolism
  • Organoids / pathology*
  • Respiration Disorders / etiology
  • Respiration Disorders / metabolism
  • Respiration Disorders / pathology*

Substances

  • DNA, Mitochondrial
  • NCOA4 protein, human
  • Nuclear Receptor Coactivators
  • Ferritins

Supplementary concepts

  • Deoxyguanosine Kinase Deficiency