Publications by authors named "Melanie H Thomas"

Parkinson's disease (PD) is a neurological disorder characterized by motor dysfunction, dopaminergic neuron loss, and alpha-synuclein (αSyn) inclusions. Many PD risk factors are known, but those affecting disease progression are not. Lifestyle and microbial dysbiosis are candidates in this context.

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Background: Cell types in ventral midbrain are involved in diseases with variable genetic susceptibility, such as Parkinson's disease and schizophrenia. Many genetic variants affect regulatory regions and alter gene expression in a cell-type-specific manner depending on the chromatin structure and accessibility.

Results: We report 20,658 single-nuclei chromatin accessibility profiles of ventral midbrain from two genetically and phenotypically distinct mouse strains.

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Dopaminergic neurons (DA neurons) are controlled by multiple factors, many involved in neurological disease. Parkinson's disease motor symptoms are caused by the demise of nigral DA neurons, leading to loss of striatal dopamine (DA). Here, we measured DA concentration in the dorsal striatum of 32 members of Collaborative Cross (CC) family and their eight founder strains.

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Dopaminergic neurons in the midbrain are of particular interest due to their role in diseases such as Parkinson's disease and schizophrenia. Genetic variation between individuals can affect the integrity and function of dopaminergic neurons but the DNA variants and molecular cascades modulating dopaminergic neurons and other cells types of ventral midbrain remain poorly defined. Three genetically diverse inbred mouse strains - C57BL/6J, A/J, and DBA/2J - differ significantly in their genomes (∼7 million variants), motor and cognitive behavior, and susceptibility to neurotoxins.

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Background: Polyunsaturated fatty acids play a crucial role in neuronal function, and the modification of these compounds in the brain could have an impact on neurodegenerative diseases such as Alzheimer's disease. Despite the fact that arachidonic acid is the second foremost polyunsaturated fatty acid besides docosahexaenoic acid, its role and the regulation of its transfer and mobilization in the brain are poorly known.

Methods: Two groups of 39 adult male BALB/c mice were fed with an arachidonic acid-enriched diet or an oleic acid-enriched diet, respectively, for 12 weeks.

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Although a major risk factor for Alzheimer's disease (AD), the "aging" parameter is not systematically considered in preclinical validation of anti-AD drugs. To explore how aging affects neuronal reactivity to anti-AD agents, the ciliary neurotrophic factor (CNTF)-associated pathway was chosen as a model. Comparison of the neuroprotective properties of CNTF in 6- and 18-month old mice revealed that CNTF resistance in the older animals is associated with the exclusion of the CNTF-receptor subunits from rafts and their subsequent dispersion to non-raft cortical membrane domains.

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Alzheimer's disease and associated diseases constitute a major public health concern worldwide. Nutrition-based, preventive strategies could possibly be effective in delaying the occurrence of these diseases and lower their prevalence. Arachidonic acid is the second major polyunsaturated fatty acid (PUFA) and several studies support its involvement in Alzheimer's disease.

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Alzheimer's disease (AD) is a neurodegenerative disease that has been linked to changes in cholesterol metabolism. Neuronal cholesterol content significantly influences the pro-apoptotic effect of amyloid-β peptide42 (Aβ42), which plays a key role in AD development. We previously reported that aged mice with reduced expression of the lipolysis stimulated lipoprotein receptor (LSR+/-), demonstrate membrane cholesterol accumulation and decreased intracellular lipid droplets in several brain regions, suggesting a potential role of LSR in brain cholesterol distribution.

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Cytosolic phospholipase A2α (cPLA2α) plays a key role in the pathogenesis of many inflammatory diseases, such as rheumatoid arthritis, atopic dermatitis and Alzheimer's disease. Therefore, inhibition of this enzyme is assumed to provide a novel therapeutic option for the treatment of these maladies. In this study we investigated the metabolism of the potent cPLA2α inhibitors 1-[3-(4-phenoxyphenoxy)-2-oxopropyl]indole-5-carboxylic acid (1) and 3-isobutanoyl-1-[3-(4-phenoxyphenoxy)-2-oxopropyl]indole-5-carboxylic acid (2).

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