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 −omic 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