Neuronal Ceroid Lipofuscinosis Mechanisms and Therapeutic Approaches

Neuronal ceroid lipofuscinoses (NCLs) comprise a group of inherited lysosomal storage disorders characterised by progressive vision loss, motor and cognitive decline, epilepsy and premature mortality. Underlying these clinical features are mutations in at least 13 CLN genes, each encoding proteins essential for lysosomal function, endocytic trafficking and autophagic turnover. Defective enzyme targeting, impaired lysosomal acidification and disrupted autophagosome maturation converge to promote accumulation of autofluorescent lipopigments within neurons. Secondary neuroinflammatory responses exacerbate neuronal vulnerability. Mechanistic insights into vesicular trafficking defects, enzyme misrouting and altered lysosomal signalling have spurred diverse therapeutic strategies. Enzyme replacement and adeno-associated virus-mediated gene therapies aim to restore deficient lysosomal activities, while small-molecule chaperones, substrate reduction approaches and modulators of autophagy or neuroinflammation offer complementary avenues. Translational research now focuses on optimising delivery, timing and outcome measures to alter the relentless course of these devastating disorders.

Research from Nature Portfolio

Recent studies have elucidated how mutations in the CLN3 protein derail endo-lysosomal trafficking. Proteomic analyses reveal CLN3 as a central hub linking the Golgi network to lysosomal reformation via the mannose-6-phosphate receptor, and show that its absence leads to mis-sorting of lysosomal enzymes and defective autophagic-lysosomal regeneration. Conversely, restoring CLN3 expression enhances lysosomal tubulation and proto-lysosome biogenesis. In parallel, investigations into v-ATPase subunit V0a1 demonstrate that its palmitoylation and adaptor-mediated targeting to the lysosomal membrane are disrupted in CLN1 models, elevating lysosomal pH. Treatment with a thioesterase-mimetic compound rescues V0a1 localisation and restores acidification, highlighting a novel mechanism to reverse lysosomal dysfunction.

Neuronal Ceroid Lipofuscinosis Mechanisms and Therapeutic Approaches publication trend

The graph below shows the total number of articles in neuronal ceroid lipofuscinosis mechanisms and therapeutic approaches across all publications each year (not limited to Nature Index journals).

Technical terms

Lysosomal storage disorder: A genetic condition in which defective lysosomal proteins cause accumulation of undegraded substrates.

Autophagy: A cellular degradation process that delivers cytoplasmic cargo to lysosomes for recycling.

Mannose-6-phosphate receptor (M6PR): A sorting receptor that directs lysosomal hydrolases from the Golgi to endosomes and lysosomes.

Palmitoylation: A reversible lipid modification that attaches palmitic acid to proteins, regulating membrane association and trafficking.

Adeno-associated virus serotype 9 (AAV9): A viral vector commonly used for gene delivery to the central nervous system.

Tripeptidyl peptidase I (TPP1): A lysosomal protease deficient in CLN2 disease, targeted by enzyme replacement therapy.

Neuroinflammation: Activation of microglia and astrocytes that can exacerbate neuronal injury in lysosomal disorders.

References

1. Loss of the batten disease protein CLN3 leads to mis-trafficking of M6PR and defective autophagic-lysosomal reformation. Nature Communications (2023).
2. Misrouting of v-ATPase subunit V0a1 dysregulates lysosomal acidification in a neurodegenerative lysosomal storage disease model. Nature Communications (2017).
3. Gene therapy ameliorates spontaneous seizures associated with cortical neuron loss in a Cln2R207X mouse model. Journal of Clinical Investigation (2023).
4. Emerging new roles of the lysosome and neuronal ceroid lipofuscinoses. Molecular Neurodegeneration (2019).
5. Autophagy Is Disrupted in a Knock-in Mouse Model of Juvenile Neuronal Ceroid Lipofuscinosis*. Journal of Biological Chemistry (2006).
6. Neuroinflammatory paradigms in lysosomal storage diseases. Frontiers in Neuroscience (2015).