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Owusu Kwarteng, D.

Publications and source records attributed to Owusu Kwarteng, D..

2 recordsLinked to original sources

Separation, isolation, and membrane lipid profiling of selectively vulnerable and resilient neurons

Certain neurons are more susceptible to pathogenic stressors and degenerate, while others remain resilient in neurodegenerative diseases. However, the mechanisms underlying this cell-to-cell heterogeneity in neuronal vulnerability remain unclear, primarily due to challenges in isolating vulnerable and resilient neurons to characterize their properties. In this study, we report the development of a novel cell-labeling method utilizing two cell-impermeable dyes to identify vulnerable and resilient neurons in culture, which are subsequently separated and isolated via fluorescence-activated cell sorting (FACS). As a proof-of-concept of a mechanistic study, we conducted lipidomic analysis to determine whether the lipid composition of membranes differs between vulnerable and resilient neurons to oxidative stress. This simple but unique method sets the groundwork for investigating the molecular underpinnings of selective neuronal vulnerability, which could inform new diagnostic strategies and therapeutic targets for neurodegenerative diseases.

neuroscience↗

Lipidated ApoE is found in nanoscale proximity to Aβ aggregates in human Alzheimer brains.

Apolipoprotein E (APOE) associates with amyloid plaques (A{beta}) in Alzheimer disease (AD). The {varepsilon}4 allele of apolipoprotein E (APOE{varepsilon}4) is the strongest genetic risk factor for sporadic AD and exacerbates A{beta} plaque burden relative to APOE{varepsilon}3 and APOE{varepsilon}2. The majority of ApoE associates with multiple lipid classes to form lipoproteins both in the brain and the periphery. However, the lipidation status of A{beta} plaque-associated ApoE is not yet fully defined. Here, we use fluorescence lifetime imaging microscopy coupled with Forster resonance energy transfer (FLIM-FRET) to determine the lipidation status of ApoE in plaques, as well as the nanoscale spatial proximity of ApoE and A{beta} to anionic lipids and cholesterol within human AD brain tissue. We demonstrate that lipids are in close nanoscale proximity to ApoE and A{beta} within A{beta} plaques. Our results reveal that lipidated ApoE complexes enriched in anionic lipids and cholesterol are core constituents of AD plaques in-situ. We propose a pathological mechanism in which the surface presentation of anionic lipids on ApoE lipoproteins facilitates initial interaction with and subsequent aggregation of A{beta}.

neuroscience↗