Influence of APOE genotype and neurotrophic factors on event related potentials (ERP-P300) of elderly with Alzheimer's Disease and healthy elderly

Abstract

Numerous clinical trials indicate that the APOE µ4 allele is the genetic marker that exhibits a more consistent association with late onset Alzheimer's disease (AD) and it is considered an increased risk factor for the development of AD in up to 4 times. Evidence for its negative impact on brain activity has been demonstrated by electroencephalograms such as event related potential (ERPs), including P300, which is impaired among elderly µ4 carriers without dementia. In addition to the APOE genotype, P300 seems to be influenced by neurotrophic factors that are decreased in AD, such as BDNF and IGF-1. However, few studies have investigated how genotype and neurotrophic factors. However, few studies have investigated how the APOE genotype and neurotrophic factors could impair the development and course of AD among individuals who already have a diagnosis of AD. Thus, the aim of the present study is to evaluate whether the APOE genotype, BDNF and IGF-1 influences the P300 of the elderly in the mild and moderate stages of Alzheimer's disease and of the elderly without dementia. To answer this question, a comparison between groups will be performed. It is a cross-sectional, observational and comparative study. The sample will consist of three groups: a group of elderly without dementia, a group of elderly in the mild stage of AD and a group in the moderate stage of AD. A subdivision in each group will be performed according to the APOE genotype, that is, subdivided between carriers and non-carriers of the µ4 allele. The following instruments will be used for data collection: Mini Mental State Exam, Clinical Dementia Rating, The Whisper Test, Geriatric Depression Scale, Clock Drawing Test, Modified Baecke Questionnaire for Older Adults. In addition, an evaluation of the ERP-P300 and laboratorial analysis to determine APOE genotype, BNDF and IGF-1 will be performed. All ethical and legal issues in research involving human subjects will be observed. It is hoped that the study may contribute to understanding the impact of this genetic marker on the cognitive processing of elderly people who have already developed the disease. In addition to data collection, data analysis and writing the final report, it is expected the publication of scientific papers, presentation in events, participation in research group meetings and courses; and a visit to a research group. (AU)