Crosstalk between Behavior and Immune System During the Prodromal Stages of Alzheimer’s Disease

The crosstalk in the functional interplay of the neuroimmune system is essential to ensure homeostasis preservation and health. Alzheimer’s disease (AD) can be understood in the context of aging of this neuroimmune communication. AD has an important genderdependent component and is benefitted by lifestyle strategies such as physical exercise, enriched environments and nutrition. Recently, the functional and redox state of peripheral immune cells has been proposed as a useful tool for measuring the progression of AD. The present review summarizes the relevance of the disruption of crosstalk among neurons, glial cells, immune mediators and cells from the very beginning of the prodromal stages of AD, when early BPSD symptoms have already started but cognitive function still seems apparently normal. The study of the role of neuroimmune system and how its disruption contributes to the onset of disease may help in understanding its biological mechanisms and in finding behavioral parameters and immunological biomarkers for the prodromic phases. Here we present results of 3xTg-AD mice from pre-morbid to early-stages of AD and how early BPSD-like symptoms correlate with changes in the organometrics of thymus and spleen that are indirect indicators of the immunological status. These functional relationships between behavioral and peripheral system also revealed the existence of differences between biological and chronological ages (an advanced biological age) since the prodromal stages. Overall, the data available suggest that the crosstalk between behavior (nervous) and immune system plays an important role since prodromal stages of AD.