Facet-Dependent Biodegradable Mn3 O4 Nanoparticles for Ameliorating Parkinson's Disease.

Parkinson's disease (PD) is a common neurodegeneration disease. Unfortunately, there are no effective measures to prevent or inhibit this disease. In this study, biodegradable Mn3 O4 nanoparticles (NPs) in different shapes are prepared and enclosed them by {100}, {200} and {103} facets that exhibit facet-dependent protection against neurotoxicity induced by oxidative damage in a cell model of PD. Notably, Mn3 O4 nanorods enclosed by {103} facets exhibit high levels of enzyme-like activity to eliminate reactive oxygen specie in vitro. It is also determined that the uptake pathway of Mn3 O4 NPs into MN9D cells is mediated by caveolin. The data demonstrate that Mn3 O4 nanorods can be taken up by cells effectively and confer excellent levels of neuroprotection while the biodegradation of Mn3 O4 NPs in vivo is confirmed by photoacoustic image of Mn3 O4 NPs in brain at 60 d. Furthermore, the oxygen scavenging effect created by Mn3 O4 nanorods is successfully applied to a mouse model of PD; the amount of α-synuclein in the cerebrospinal fluid of PD mice is reduced by 61.2% in two weeks, thus demonstrating the potential application of facet-directed Mn3 O4 NPs for the clinical therapy of neurodegenerative disease.