Study identifies lipid imbalance in fruit fly model of ALS8, implicating neuro-glial dysfunction
Researchers using a Drosophila model of ALS8 found that a mutated VAPB protein disrupts lipid homeostasis in the brain, with cholesterol esters and sphingolipids accumulating while cholesterol decreases. The lipid imbalance occurs in both neurons and glial cells and correlates with progressive motor dysfunction. The findings suggest lipid dysregulation may be a key mechanism in ALS8 pathogenesis, potentially opening new therapeutic avenues.
A preprint study published on bioRxiv examined how a pathogenic VAPB mutation causes ALS8, a form of familial amyotrophic lateral sclerosis characterized by motor neuron degeneration. Using a Drosophila model carrying the equivalent VAPBP58S mutation, researchers discovered age-dependent disruptions in brain lipid homeostasis: cholesterol esters and sphingolipids accumulated while total cholesterol decreased. Notably, while neutral lipids accumulated in the brain, they did not correlate with increased lipid droplets, which were actually fewer and smaller than normal. By selectively manipulating VAPB activity in neurons versus glial cells, the team found both cell types contribute to lipid dysregulation through different mechanisms, with glial lipid droplet flux being particularly dependent on VAPB. The findings suggest that lipid imbalance along the neuro-glial axis may be a critical pathogenic feature of ALS8.
Limitations & open questions
The study is a preprint and has not undergone peer review. The authors do not discuss whether their findings in Drosophila translate to human ALS8 patients, potential therapeutic interventions targeting lipid homeostasis, or how this mechanism relates to other known ALS pathways.
What different sources said
- bioRxivCenter
Neuro-glial lipid imbalance in a Drosophila model of Amyotrophic Lateral Sclerosis 8
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