Researchers Report Protease-Resistant D-Amino Acid Mini-Chaperone Peptide Protects Against Amyloid-Beta Toxicity in C. elegans

Researchers developed a protease-resistant D-amino acid mini-chaperone peptide that extends lifespan and reduces amyloid-beta toxicity in C. elegans, offering a potential therapeutic approach for protein-misfolding diseases.

University of Missouri researchers synthesized a D-amino acid analog of the αA-crystallin-derived mini-chaperone peptide, named D-MC-αA, to overcome the proteolytic instability of the parent L-amino acid peptide.

In biochemical assays, D-MC-αA exhibited approximately threefold greater chaperone activity than its L-amino acid parent, completely resisted enzymatic degradation, and enhanced copper-mediated antioxidant activity.

In C. elegans models, the synthetic peptide was efficiently internalized, prolonged lifespan, enhanced thermotolerance, and significantly delayed paralysis and mortality induced by amyloid-β proteotoxicity.

While molecular chaperones represent a promising strategy to treat protein-misfolding disorders, clinical translation of peptide-based candidates is often limited by rapid in vivo enzymatic breakdown.

The study shows that total D-amino acid substitution can successfully confer complete protease resistance while simultaneously enhancing biochemical chaperone and cytoprotective activities.

Preclinical validation of D-amino acid peptide modifications may support the development of highly stable peptide-based therapeutics targeting neurodegenerative conditions like Alzheimer's disease.

The findings offer an alternative formulation route for targeting extracellular and intracellular protein aggregation, a major area of active investment in the neurodegeneration and longevity sectors.

Subsequent studies evaluating the pharmacokinetic profile, blood-brain carrier penetration, and safety of D-MC-αA in mammalian models of proteotoxicity.