Frontiers in Neurology (Feb 2019)

Developmental Comparison of Ceramide in Wild-Type and Cln3Δex7/8 Mouse Brains and Sera

  • Sally El-Sitt,
  • Jihane Soueid,
  • Jamal Al Ali,
  • Joelle Makoukji,
  • Nadine J. Makhoul,
  • Hayat Harati,
  • Rose-Mary Boustany

DOI
https://doi.org/10.3389/fneur.2019.00128
Journal volume & issue
Vol. 10

Abstract

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CLN3 disease is a neurodevelopmental disease leading to early visual failure, motor decline, and death. CLN3 pathogenesis has been linked to dysregulation of ceramide, a key intracellular messenger impacting various biological functions. Ceramide is upregulated in brains of CLN3 patients and activates apoptosis. Ceramide levels over the lifespan of WT and Cln3Δex7/8 mice were measured using the DGK assay. Ceramide subspecies were determined by LC-MS. Ceramide synthesis enzymes and pre- and post-synaptic mRNA expression was measured in Cln3Δex7/8 and normal mouse brains. Neuronal cell death was established by PARP cleavage and Caspases 3/6/9 and cytochrome C mRNA expression in Cln3Δex7/8 and normal mouse brains. In WT mouse, a ceramide peak was noted at 3 weeks of age. The absence of this peak in Cln3Δex7/8 mice might be related to early disease pathogenesis. Increase of ceramide in Cln3Δex7/8 mouse brain at 24 weeks of age precedes neuronal apoptosis. The correlation between serum and brain ceramide in WT mice, and dysregulation of ceramide in serum and brain of Cln3Δex7/8 mice, and the significant increase in ceramide in Cln3Δex7/8 mouse brains and sera argue for use of easily accessible serum ceramide levels to track response to novel therapies in human CLN3 disease.

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