Co-aggregation with Apolipoprotein E modulates the function of Amyloid-ß in Alzheimer's disease.

Which isoforms of apolipoprotein E (apoE) we inherit determine our risk of developing late-onset Alzheimer's Disease (AD), but the mechanism underlying this link is poorly understood. In particular, the relevance of direct interactions between apoE and amyloid-ß (Aß) remains controversial. Here, single-molecule imaging shows that all isoforms of apoE associate with Aß in the early stages of aggregation and then fall away as fibrillation happens. ApoE-Aß co-aggregates account for ~50% of the mass of diffusible Aß aggregates detected in the frontal cortices of homozygotes with the higher-risk APOE4 gene. We show how dynamic interactions between apoE and Aß tune disease-related functions of Aß aggregates throughout the course of aggregation. Our results connect inherited APOE genotype with the risk of developing AD by demonstrating how, in an isoform- and lipidation-specific way, apoE modulates the aggregation, clearance and toxicity of Aß. Selectively removing non-lipidated apoE4-Aß co-aggregates enhances clearance of toxic Aß by glial cells, and reduces secretion of inflammatory markers and membrane damage, demonstrating a clear path to AD therapeutics.

A Parkinson's Disease-relevant Mitochondrial and Neuronal Morphology High-throughput Screening Assay in LUHMES Cells.

Parkinson's disease is a devastating neurodegenerative disorder affecting 2-3% of the population over 65 years of age. There is currently no disease-modifying treatment. One of the predominant pathological features of Parkinson's disease is mitochondrial dysfunction, and much work has aimed to identify therapeutic compounds which can restore the disrupted mitochondrial physiology. However, modelling mitochondrial dysfunction in a disease-relevant model, suitable for screening large compound libraries for ameliorative effects, represents a considerable challenge. Primary patient derived cells, SHSY-5Y cells and in vivo models of Parkinson's disease have been utilized extensively to study the contribution of mitochondrial dysfunction in Parkinson's. Indeed many studies have utilized LUHMES cells to study Parkinson's disease, however LUHMES cells have not been used as a compound screening model for PD-associated mitochondrial dysfunction previously, despite possessing several advantages compared to other frequently used models, such as rapid differentiation and high uniformity (e.g., in contrast to iPSC-derived neurons), and relevant physiology as human mesencephalic tissue capable of differentiating into dopaminergic-like neurons that highly express characteristic markers. After previously generating GFP+-LUHMES cells to model metabolic dysfunction, we report this protocol using GFP+-LUHMES cells for high-throughput compound screening in a restoration model of PD-associated mitochondrial dysfunction. This protocol describes the use of a robust and reproducible toxin-induced GFP+-LUHMES cell model for high throughput compound screening by assessing a range of mitochondrial and neuronal morphological parameters. We also provide detailed instructions for data and statistical analysis, including example calculations of Z'-score to assess statistical effect size across independent experiments.

Benzyl alcohol oxidation with Pd-Zn/TiO2: computational and experimental studies.

Pd-Zn/TiO2 catalysts containing 1 wt% total metal loading, but with different Pd to Zn ratios, were prepared using a modified impregnation method and tested in the solvent-free aerobic oxidation of benzyl alcohol. The catalyst with the higher Pd content exhibited an enhanced activity for benzyl alcohol oxidation. However, the selectivity to benzaldehyde was significantly improved with increasing presence of Zn. The effect of reduction temperature on catalyst activity was investigated for the catalyst having a Pd to Zn metal molar ratio of 9:1. It was found that lower reduction temperature leads to the formation of PdZn nanoparticles with a wide particle size distribution. In contrast, smaller PdZn particles were formed upon catalyst reduction at higher temperatures. Computational studies were performed to compare the adsorption energies of benzyl alcohol and the reaction products (benzaldehyde and toluene) on PdZn surfaces to understand the oxidation mechanism and further explain the correlation between the catalyst composition and its activity.