The role of metabolic syndrome in Alzheimer’s disease

Background: Metabolic syndrome (MS) leads to the deposits formation of insoluble protein aggregates, neuroinflammation, oxidative stress, neuronal insulin resistance, progressive insulin resistance, desensitization and β-amyloid amyloidosis in the brain, besides direct ischemic effects which are closely associated with Alzheimer’s disease (AD).1 Objectives: The present study seeks to understand the role of the metabolic syndrome in the pathophysiology of Alzheimer’s disease and to describe preventive and therapeutic interventions. Methods: PUBMED and Web of Science were the databases used, the following descriptors were used to search the articles: “Alzheimer Disease” OR “Alzheimer Dementia” AND “Metabolic Syndrome”. Results: The studies in general have shown that MS is related to AD through brain insulin resistance, triggered by oxidative stress and neuroinflammation. It is related to the progressive atrophy of brain regions involved in the progression of AD. Insulin resistance in the brain is related to the progressive atrophy of the brain regions from initial progression of AD. These regions are cingulate cortices, medial temporal lobe, prefrontal gyri and other regions.³ Thus, there is an inhibition of the mechanisms of beta-amyloid removal, leading to its accumulation, which generates neuroinflammation, that in turn potentiates insulin resistance in the central nervous system, contributing to the genesis and progression of cognitive damage.2,3 Conclusions: Insulin resistance plays a major role in the initiation and perpetuation of cognitive impairment in AD. Furthermore, the components of the MS associated with AD, when treated with preventive and therapeutic measures, break this association by promoting rebalancing of the metabolism.