Small molecule biomarkers in Alzheimer’s disease

Abstract

-Alzheimer's disease (AD) is a progressive neurodegenerative disease which affects a growing number of people as the population ages worldwide. Alzheimer's Disease International estimated that more than 100 million people will be living with dementia by 2050. At present there are no disease-modifying therapies and research has expanded to the Àomic sciences with scientists aiming to get a holistic view of the disease using systems medicine. Metabolomics and Lipidomics give a snap-shot of the metabolism. As analyzing the brain in vivo is difficult, the metabolic information of the periphery has potential to unravel mechanisms that have not been considered, such as those that link the brain to the liver and the gut or other organs. With that in mind we have produced a mini-review, to record a number of studies in the field and the molecular pathways that have been flagged in animal and human models of AD. Human studies deal with cohorts in the order of the hundreds due to the difficulty of organizing AD studies, however it is possible that these first pilots point towards important mechanisms. The trend in these small studies is the involvement of many organs and pathways. Some findings, that have been reproduced, are ceramides being increased, phospholipids and neurotransmitters depleted and sterols being found depleted too. Initial findings point to an important role to lipid homeostasis in AD, this is not surprising as the brain's main constituents are water and lipids.Keywords: Alzheimer's disease / metabolomics / lipidomics / biomarker Résumé -Biomarqueurs à petites molécules dans la maladie d'Alzheimer. La maladie d'Alzheimer est une maladie neurodégénérative progressive qui affecte un nombre croissant de personnes en raison du vieillissement de la population observé dans le monde entier. La fédération internationale d'associations Alzheimer's disease International estime que plus de 100 millions de personnes vivront avec cette démence d'ici à 2050. Il n'existe actuellement aucun traitement de la maladie et la recherche s'est élargie aux sciences -omiques avec l'objectif scientifique d'obtenir une approche globale de la maladie en utilisant une médecine des systèmes. La métabolomique et la lipidomique donnent un aperçu du métabolisme. L'analyse du cerveau in vivo s'avérant difficile, l'information métabolique de la périphérie possède le potentiel de démêler des mécanismes qui n'ont pas été pris en compte, tels que ceux reliant le cerveau au foie et à l'intestin ou à d'autres organes. Dans cet esprit, nous proposons une mini-revue, afin de lister un certain nombre d'études relevant de ce champ et les voies moléculaires qui ont été signalées chez les modèles animaux et humains de la maladie d'Alzheimer. Les études humaines traitent des cohortes de quelque centaines d'individus en raison de la difficulté à organiser des études sur cette pathologie, mais il est possible que ces premiers pilotes pointent vers des mécanismes importants. La tendance dans ces petites études est l'implication de nombreux org...

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