bims-tofagi Biomed News
on Mitophagy
Issue of 2025–05–04
three papers selected by
Michele Frison, University of Cambridge



  1. Alzheimers Dement. 2025 Apr;21(4): e70198
       INTRODUCTION: Phosphorylated ubiquitin (p-S65-Ub) is generated during PINK1-PRKN mitophagy as a specific marker of mitochondrial damage. Despite the widespread deposition of p-S65-Ub in aged and diseased human brain, the genetic contribution to its accumulation remains unclear.
    METHODS: To identify novel mitophagy regulators, we performed a genome-wide association study using p-S65-Ub level as a quantitative trait in 1012 autopsy-confirmed Lewy body disease (LBD) samples.
    RESULTS: We identified a significant genome-wide association with p-S65-Ub for rs429358 (apolipoprotein E ε4 [APOE4]) and a suggestive association for rs6480922 (ZMIZ1). APOE4 was associated with higher p-S65-Ub levels and greater neuropathological burden. Functional validation in mouse and human induced pluripotent stem cell (iPSC) models confirmed APOE4-mediated mitophagy alterations. Intriguingly, ZMIZ1 rs6480922 was associated with lower p-S65-Ub levels, reduced neuropathological load, and increased brain weight, indicating a potential protective role.
    DISCUSSION: Our findings underscore the importance of mitochondrial quality control in LBD pathogenesis and nominate regulators that may contribute to disease risk or resilience.
    HIGHLIGHTS: p-S65-Ub levels were used as a quantitative marker of mitochondrial damage. A GWAS identified two genetic variants that modify mitophagy in LBD autopsy brain. APOE4 was associated with increased p-S65-Ub accumulation and neuropathology. APOE4 altered mitophagy via pathology-dependent and pathology-independent mechanisms. ZMIZ1 was linked to reduced p-S65-Ub and neuropathology indicative of protection.
    Keywords:  GWAS; PINK1; PRKN; Parkin; Parkinson's disease; ZMIZ1; autophagy; mitochondria; phosphorylated ubiquitin; ubiquitin
    DOI:  https://doi.org/10.1002/alz.70198
  2. Hum Mol Genet. 2025 Apr 30. pii: ddae179. [Epub ahead of print]
      Neurodegenerative disorders (NDDs), characterized by a progressive loss of neurons and cognitive function, are a severe burden to human health and mental fitness worldwide. A hallmark of NDDs such as Alzheimer's disease, Huntington's disease, Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and prion diseases is disturbed cellular proteostasis, resulting in pathogenic deposition of aggregated protein species. Autophagy is a major cellular process maintaining proteostasis and integral to innate immune defenses that mediates lysosomal protein turnover. Defects in autophagy are thus frequently associated with NDDs. In this review, we discuss the interplay between NDDs associated proteins and autophagy and provide an overview over recent discoveries in inborn errors in canonical autophagy proteins that are associated with NDDs. While mutations in autophagy receptors seems to be associated mainly with the development of ALS, errors in mitophagy are mainly found to promote PD. Finally, we argue whether autophagy may impact progress and onset of the disease, as well as the potential of targeting autophagy as a therapeutic approach. Concludingly, understanding disorders due to inborn errors in autophagy-"autophagopathies"-will help to unravel underlying NDD pathomechanisms and provide unique insights into the neuroprotective role of autophagy, thus potentially paving the way for novel therapeutic interventions.
    Keywords:  autophagy; innate immunity; monogenic diseases; neurodegenerative diseases
    DOI:  https://doi.org/10.1093/hmg/ddae179
  3. Sci Rep. 2025 Apr 29. 15(1): 15078
      This study investigated the roles and mechanisms of PINK1 activity in neonatal hypoxia-induced seizures with shRNA intervention targeting translocase outer mitochondrial membrane 7 (TOM7), the positive regulator of PINK1 autophosphorylation, or overlapping with the m-AAA protease 1 homolog (OMA1), the negative regulator of PINK1 autophosphorylation. Studies have suggested that in hypoxia-induced neonatal seizures, the phosphorylation level of PINK1 is significantly increased and the mitophagic pathway is activated, accompanied by neuronal damage and learning-memory deficits. Inhibiting PINK1 phosphorylation by reducing TOM7 expression alleviated mitophagy, mitochondrial oxidative stress, neuronal damage and seizures. In contrast, the inhibition of OMA1 expression resulted in a further increase in PINK1 phosphorylation and aggravated hypoxia-induced seizures and neuronal injury. This study implicated PINK1 activity in neonatal hypoxia and suggest that attenuated PINK1 autophosphorylation may have neuroprotective and anti-seizure effects in neonatal hypoxia.
    Keywords:  Mitochondrial oxidative stress; Mitophagy; Neuronal injury; PINK1; Seizure
    DOI:  https://doi.org/10.1038/s41598-025-99915-8