A Metal-Peptide Framework as a Nanozyme for the Attenuation of Amyloid‑β Aggregation and Reactive Oxygen Species

Alzheimer's disease (AD) is an irreversible neurodegenerative disease characterized by abnormal performance in memory, cognition, and language, and it imposes a heavy economic burden worldwide. Amyloidosis and oxidative stress are highly associated with AD progression, yet limited clinical drugs are available at present. Nanozymes exhibit diverse enzyme-mimetic activities and have attracted widespread attention as a promising alternative candidate for scavenging reactive oxygen species to maintain the oxidation-antioxidation balance in cells. Neurotoxic amyloid-β (Aβ) aggregation is also a critical event in AD pathology. The development of dual-targeting nanomaterials with antiamyloidosis ability and enzyme-mimicking activity is expected to be a promising strategy for the treatment of amyloidosis and reactive oxygen species-mediated AD progression. Here, bimetallic-peptide framework nanozymes (CuZn-PEP NZs) with amyloid-β (Aβ) attenuating ability, multiple enzyme-mimicking properties, and broad-spectrum reactive oxygen species scavenging capacity were endowed to inhibit Aβ fibrillization, disaggregate Aβ fibrils, and scavenge Aβ fibril-induced reactive oxygen species. An obvious inhibitory effect on Aβ fibrillization and a disaggregation effect on Aβ fibrils were observed after treatment with CuZn-PEP NZs. Meanwhile, the cytotoxicity of Aβ fibrils toward PC12 cells was significantly reduced by CuZn-PEP NZs. Meanwhile, CuZn-PEP NZs with multiple redox pairs exhibit superoxide dismutase, catalase, and glutathione peroxidase-mimicking enzyme properties simultaneously, which further display cytoprotective effects against Aβ fibril-induced reactive oxygen species and mitochondrial damage. Besides, cellular studies verified that CuZn-PEP NZs possess excellent biocompatibility and blood-brain barrier penetration capacity. Overall, these bimetallic-peptide framework nanozymes represent a promising perspective for attenuation of amyloid-β aggregation and reactive oxygen species simultaneously, which highlights the potential of nanozymes for the treatment of amyloidosis and reactive oxygen species-mediated AD progression.