Zinc-mediated lysosomal activation by 1H10 enhances autophagy and attenuates tau pathology in Alzheimer's disease models.

Abstract

Impaired autophagic flux and lysosomal dysfunction contribute critically to the accumulation of pathological protein aggregates in Alzheimer's disease (AD). Emerging evidence suggests that intracellular zinc dynamics regulate lysosomal function by modulating processes such as acidification and lysosomal biogenesis. We previously identified 1H10 as an AMP-activated protein kinase (AMPK) inhibitor and subsequently demonstrated its zinc-binding capacity and ability to regulate intracellular zinc homeostasis. Building on our prior findings that intra-lysosomal zinc promotes acidification and activates transcription factor EB (TFEB), we investigated whether 1H10 enhances lysosomal function through zinc mobilization in neurons, thereby improving autophagy and reducing pathological protein accumulation. In primary cortical neurons, 1H10 increased lysosomal abundance and enhanced lysosomal degradative capacity in a zinc-dependent manner, as demonstrated by increased cathepsin B activity and DQ-BSA degradation. It alleviated lysosomal dysfunction induced by v-ATPase inhibition and promoted autophagic flux, leading to reduced accumulation of amyloid-β (Aβ) and tau in neuronal models. In 5XFAD mice, 1H10 treatment showed trends toward improved spatial learning in the Morris water maze, reduced tau phosphorylation at Thr205 and Ser214, normalized LC3-II levels, and restored autophagic-lysosomal homeostasis, without significant changes in extracellular amyloid plaque burden. These findings indicate that zinc-mediated lysosomal activation by 1H10 enhances the autophagy-lysosomal pathway and attenuates tau pathology in AD models, suggesting that targeting lysosomal function may represent a potential therapeutic strategy for neurodegenerative disorders characterized by impaired proteostasis.