DMT1 knockout abolishes ferroptosis induced mitochondrial dysfunction in C. elegans amyloid β proteotoxicity

Area of Science:

• Neuroscience
• Biochemistry
• Cell Biology

Background:

• Iron is essential for neuronal function but dysregulation contributes to neurodegenerative diseases like Alzheimer's disease (AD).
• Elevated brain iron levels are observed in AD patients, but its role in pathogenesis remains unclear.
• Ferroptosis, an iron-dependent cell death pathway, is implicated in neurodegeneration.

Purpose of the Study:

• To investigate the role of ferroptosis in mediating AD-like pathologies in a C. elegans model.
• To determine the relationship between iron accumulation, neuronal dysfunction, and amyloid beta (Aβ) toxicity.

Main Methods:

• Utilized C. elegans models, including wild-type and neuronal Aβ-overexpressing worms.
• Assessed iron accumulation, neuronal function, energetic imbalance, and mitochondrial reactive oxygen species (ROS).
• Investigated the effects of pharmacologic modulation of iron levels and knockout of divalent metal transporter 1 (DMT1).

Main Results:

• Iron accumulation preceded neuronal dysfunction in aging worms.
• Iron-induced neuronal dysfunction involved energetic imbalance and mitochondrial ROS-mediated oxidative damage, leading to ferroptosis.
• Neuronal Aβ expression increased sensitivity to ferroptosis, which was mitigated by DMT1 knockout.
• DMT1 knockout completely suppressed age-dependent Aβ toxicity by reducing neuronal iron uptake.

Conclusions:

• Iron-induced ferroptosis exacerbates mitochondrial dysfunction and oxidative damage in the context of neuronal Aβ overexpression.
• Targeting iron uptake, specifically through DMT1, offers a potential therapeutic strategy for mitigating Aβ-associated neurodegeneration.