Aspartylglycosaminuria: a review.

Area of Science:

• Biochemistry
• Genetics
• Lysosomal Storage Diseases

Background:

• Aspartylglucosaminuria (AGU) is a rare, inherited lysosomal storage disease impacting glycoprotein degradation.
• It is prevalent in the Finnish population, causing lifelong physical and cognitive impairments.

Purpose of the Study:

• To investigate the genetic basis of AGU in the Finnish population.
• To establish and characterize an AGU mouse model for therapeutic studies.
• To evaluate the efficacy of enzyme replacement therapy in the AGU mouse model.

Main Methods:

• Genetic analysis of the AGA gene in Finnish AGU patients.
• Generation of a knockout mouse model (Aga-deficient) by disrupting the Aga gene.
• Treatment of AGU mice with recombinant glycosylasparaginase (AGA) and assessment of therapeutic effects.

Main Results:

• A specific C163S mutation in the AGA gene accounts for 98% of Finnish AGU cases, simplifying diagnosis.
• Aga-deficient mice exhibit key clinical and biochemical features of human AGU.
• Recombinant AGA treatment corrected AGU pathology in non-neuronal tissues and reduced aspartylglucosamine accumulation in the brain.

Conclusions:

• The C163S mutation is the primary cause of AGU in Finland, facilitating genetic screening.
• The AGU mouse model accurately recapitulates the human disease, serving as a valuable preclinical tool.
• Enzyme replacement therapy shows promise for treating non-neuronal manifestations of AGU, warranting further investigation in human patients.