๐ก Researchers investigated whether specific microbiome characteristics in stool samples correlated with preclinical Alzheimerโs disease (AD) status or established AD biomarkers and determined whether microbiome characteristics could improve the performance of machine learning classifiers designed to distinguish healthy individuals from those with preclinical AD.
๐ Gut dysfunction and aberrant microbial content may contribute to the pathogenesis of AD and potentially other neurodegenerative diseases. AD pathobiology is thought to progress from cognitively normal with no evidence of disease to apparently cognitively normal with biomarker evidence of disease (preclinical AD) and to symptomatic AD.
๐ Changes in the gut microbiome correlate with the presence of cerebrospinal fluid markers of AD, including phosphorylated tau-181 (p-tau-181) and Aฮฒ (measured by the Aฮฒ42/Aฮฒ40 ratio). Variations in the bacterial composition of stool in symptomatic patients with AD were accompanied by a dysregulated P-glycoprotein pathway in gut epithelial cells, an alteration that contributes to enteric inflammation and disrupted organ homeostasis.
๐ The microbial pathways most associated with preclinical AD status in regression models (l-arginine, l-ornithine, and 4-aminobutanoate degradation) share succinate as a product. ๐๐ฆ๐ต๐ฉ๐ข๐ฏ๐ฐ๐ฃ๐ณ๐ฆ๐ท๐ช๐ฃ๐ข๐ค๐ต๐ฆ๐ณ ๐ด๐ฎ๐ช๐ต๐ฉ๐ช๐ช was associated with preclinical AD and was negatively correlated with fecal concentrations of butyrate, a SCFA.
๐ด Researchers in this study explore the associations between the gut microbiome and AD. They found that preclinical AD status or AD markers supported the existence of an enteric neuroimmune axis in neurodegenerative disease.
They observed that the addition of gut microbiome features improved accuracy, sensitivity, and specificity of classifiers for preclinical AD.
Microbiome markers in stool might complement early screening measures for preclinical AD and generate encouraging hypotheses about potential roles of the gut in AD progression.
Link to the article: bit.ly/42VL6hM
Published On: /06/2023
