ABSTRACT
Amyloid-ß (Aß) peptide and α-synuclein (α-syn) are major components of senile plaques in Alzheimer's disease (AD) and Lewy bodies in Parkinson's disease (PD), respectively. Co-occurrence of Aß and α-syn in the senile brains of AD and LB diseases suggests interactions between the two proteins. However, the significance of the overlapping deposition, especially the effects of α-syn on the Aß aggregation, still remains to be clarified. In the present study, we investigated the effects of α-syn pre-formed fibrils (PFFs) injection on the cognitive behaviors and Aß deposition in the brain of APP/PS1 transgenic AD mice by using Morris water maze (MWM) test, immunohistochemistry and western blot techniques. We found that APP/PS1 transgenic mice exhibited an obvious elevation in the α-syn load, as well as Aß deposition in the brain compared with wild type of C57 BL littermates. 5 months after cerebral injection of exogenous α-syn, MWM tests showed an alleviation in cognitive impairments in APP/PS1 mice; western blot and immunohistochemistry experiments also exhibited a significant reduction in Aß level in the brain of APP/PS1 mice injected with α-syn. These results suggest that α-syn aggregated in the brain of AD may act as a protective factor and defend the brain tissue from early Aß deposition and cognitive deficits.
Subject(s)
Spatial Memory/drug effects , alpha-Synuclein/pharmacology , Alzheimer Disease/physiopathology , Amyloid beta-Peptides/metabolism , Amyloid beta-Protein Precursor/metabolism , Animals , Brain/metabolism , Cognition Disorders/metabolism , Cognitive Dysfunction/metabolism , Disease Models, Animal , Humans , Male , Maze Learning , Memory Disorders/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Plaque, Amyloid , Presenilin-1/metabolism , Protein Aggregation, PathologicalABSTRACT
Developing highly efficient, low-cost, and multifunctional electro-catalysts to replace noble metals is of significant importance for energy storage and conversion systems. Herein, we demonstrate a facile strategy for the preparation of CoP quantum dots (QDs) embedded in S,N-codoped graphite carbon (CoP@SNC) by using organophosphoric acid as both phosphorus and carbon sources. Benefiting from the strong coupling and synergistic effect between CoP QDs and highly conductive S,N-codoped carbon, well-structured porosity and high specific surface area, the resulting CoP@SNC exhibits excellent activities for oxygen evolution reaction (OER), hydrogen evolution reaction (HER), and oxygen reduction reaction (ORR), making it a trifunctional electro-catalyst for overall water splitting and rechargeable Zn-air batteries. When CoP@SNC is used for overall water splitting, a cell voltage as low as 1.64 V is required to reach the current density of 10 mA cm-2; the obtained rechargeable Zn-air battery with CoP@SNC as the air cathode exhibits a high open-circuit voltage of 1.45 V, a very low discharge-charge voltage gap (0.83 V at 10 mA cm-2), and a long cycle life (up to 180 cycles). This work not only offers a new strategy for the synthesis of CoP@SNC but also presents its huge potential as a trifunctional electro-catalyst for clean energy systems.