Comparação dos efeitos neuroprotetores do enriquecimento ambiental, do exercício físico e da socialização em um modelo animal de doença de Alzheimer

Abstract

Alzheimer's Disease (AD) is an incurable disease that causes loss of cognitive functions (memory, orientation, attention, and language). Brain lesions are characteristic of this disease, in which main alterations being: senile plaques arisvel from the deposition of abnormally produced beta-amyloid protein (βa) and neurofibrillary tangles. Many approaches have been proposed to treat or prevent AD, but studies generally use protocols that becouse difficult to attribute a cause-effect relationship because they involve more than one variable that could be benefical in observed changes. The objective of this work was to evaluate and isolate the neuroprotective effects of environmental enrichment, anaerobic physical exercise, and social enrichment on memory deficits related to beta-amyloid neurotoxicity in an animal model. For this, Wistar rats were submitted to 8 weeks of intervention, and soon thereafter underwent stereotactic surgery for the injection of βa into the hippocampus. The memory was evaluated by object recognition and social recognition memory tests, considering short and long term memory. The oxidative state of the hippocampus (ROS, TBARS and FRAP) and acetylcholinesterase (AChE) activity are also verified. The data show that the injection of βa resulted in memory deficits and oxidative damage in the hippocampus. Environmental enrichment and exercise avoided all memory deficits and hippocampal lipid peroxidation (TBARS) induced by βa. Social enrichment avoided only the social 10 recognition memory deficit and avoided the total antioxidant capacity (FRAP) decrease induced by βa.