Estresse oxidativo: estudo comparativo de granulócitos humanos de doadores com doença de Alzheimer e durante o processo de envelhecimento, estimulados ou não com adrenalina

Abstract

Many authorshave related aging, oxidative stress and a decline in the immune system throughout the Alzheimer´s Disease (DA). Some hormones, for example the adrenaline, act as modulators in this related system and a an imbalance in hormonal action mechanisms can be a factor for the predisposition in the Alzheimer´s Disease evolution. In this context, the objective of this dissertation was to evaluate the adrenaline´s effect in the control and exacerbation of the oxidative stress in patients with or without the Alzheimer´s Disease during the aging process. Human granulocytes were used and divided into 2 groups: with the DA (1) divided in three age groups: 20-39, 40-59, 60-80 and with DA (2) from 60-80 years old. Three protocols were evaluated: MTT assays (evaluates the cellular reduction system), NO production (evaluates cellular oxidative capacity) and phagocytosis with zimozan opsonized with C3B (ZC3b), by optical microscopy. The three protocols were evaluated in presence and absence of adrenaline, stimulating or not phagocytosis by ZC3b. The adrenaline concentrations chosen were determined through a dose-response curve among six concentrations, which presented a cellular viability of 95% and potential effect. According to the presented results, it was concluded that during the aging process phagocytosis, antioxidant capacity and immune protection were declined. In comparison to DA, donors of the same age group presented a higher cellular reduction capacity and a diminished production of NO, but with similar phagocytosis. The challenge with adrenaline demonstrated its influence in the neuro-immune-endocrine system during aging being a preponderant factor for the emergence of pathologies such as DA.