ZnO Nanoflower petals mediated amyloid degradation - An in vitro electrokinetic potential approach

Abstract

An electrokinetic potential (ζ-potential) based approach was introduced to address the amyloid degradation on ZnO-nanoflower platform. The hallmark of neurodegenerative disorders like Alzheimer's disease, Parkinson's disease (PD), Creutzfeldt-Jakob Disease (CJD), Prion- associated diseases, type-II diabetes, etc. is the deposition of misfolded protein aggregates predominantly β-sheeted in structure and fibrillar morphology, known as amyloids, in the brain and different parts of the body. Agents that can degrade these amyloids can be potential candidate for the therapy of amyloidosis. Ultrasmall nanoparticles are gaining interest due to their ability to cross blood brain barrier (BBB) which is favorable for the treatment of neurodegenerative disorders. Considering the influence of Zn2+ in the formation of Aβ aggregates instead of fibrillation, the present study was designed based on the ZnO nanoparticles (ZnO-NP) and ZnO nanoflowers (ZnO-NF) to compare the anti amyloid ability using a model huminsulin amyloid. Fluorescence study, atomic force microscopy (AFM), IR spectroscopy (FTIR) and reduction of fibril size using dynamic light scattering showed that ZnO-NF can degrade amyloids with a higher capacity than their nanoparticle counterpart. Significant reduction in magnitude of ζ-potential in ZnO-NF treated huminsulin amyloid supported the notion to come to the consensus and became the new indicator for anti-amyloidosis. The cell viability assay of ZnO-NP and ZnO-NF at a higher dose than that used for amyloid degradation using PC12 and HaCaT cell lines showed their biocompatibility in a safe manner. Thus, it can be suggested that ZnO-NF would be a better candidate for amyloid degradation compared to ZnO-NPs due to higher surface to volume ratio of the petals.