Pyroglutamate-modified N-terminal truncated amyloid-beta (AβpE3)

Pyroglutamate-modified N-terminal truncated amyloid-beta (AβpE3) is a highly pathogenic and aggregation-prone variant of the amyloid-beta peptide, characterized by the cyclization of an N-terminal glutamate residue into pyroglutamate [1.3.1, 1.4.1]. This modification, catalyzed by the enzyme glutaminyl cyclase, increases the peptide's stability, hydrophobicity, and resistance to degradation, making it a primary component of the insoluble plaque cores found in Alzheimer's disease brains [1.3.2, 1.3.5]. AβpE3 acts as a potent seed for the aggregation of other amyloid-beta species, accelerating the formation of toxic oligomers and mature plaques that lead to synaptic loss and neurodegeneration [1.3.1, 1.4.3]. Therapeutic strategies targeting this molecule include monoclonal antibodies like donanemab, which specifically recognize the pGlu-Aβ epitope to facilitate immune-mediated clearance of established plaques [1.2.1, 1.2.2]. Clinical trials have demonstrated that clearing these specific aggregates can significantly slow cognitive and functional decline in early-stage Alzheimer's patients [1.2.3, 1.2.5]. However, treatment is associated with risks such as amyloid-related imaging abnormalities (ARIA), which require careful monitoring via MRI [1.4.2, 1.4.4].

Other names

pGlu-AβAβpE3N3pG-AβPyroglutamate-3 amyloid-betaN-truncated pyroglutamate amyloid-betapGlu3-AβAβ3pE-42

Monoclonal antibodies selectively bind to the pyroglutamate-modified N-terminus of amyloid-beta in plaques, triggering microglial-mediated phagocytosis and subsequent plaque clearance [1.2.2, 1.2.4]. Small molecule inhibitors target glutaminyl cyclase to prevent the formation of the pyroglutamate modification [1.3.1, 1.3.5].