Injeção intracerebroventricular de formas amiloides em zebrafish (Danio rerio) adultos jovens e idosos : efeitos comportamentais e proteômicos

Abstract

The Alzheimer Disease (AD) is a progressive neurodegenerative disease, being the most common form of dementia in elderly people. Despite the prevalence and severity of this disease there are few therapeutic agents available, and their effectiveness is low, restrained to slow or attenuate the symptoms during an initial period after the diagnosis. Preventive or effective treatment for this pathology are not available, mostly because the lack of understanding of the physiopathological mechanisms responsible for the disease progression. The zebrafish is an interesting animal model for studying AD because of its fast development, genetic resemblance with humans and its easy husbandry. This thesis presents a strategy is based on cerebroventricular (CV) injection of Aβ42 in monomeric, oligomeric and protofibrillar states on young (6 months) and old (36 months) adults. The animals CV injected showed behavioral and locomotor differences between the two age groups, where only old animals showed an exploratory deficit in the groups injected with oligomeric and protofibrillar solution at 7 days post injection (dpi). However, these same solutions caused cognitive deficit observed in the inhibitory avoidance experiment in young and old adults after 21 dpi. Brain of these animals were analyzed by Mass Spectrometry comparatively and proteins with variations of at least 1.5 times were divided between groups based on their function as related to neurotransmission, immune system, metabolism and mitochondrial activity. Furthermore, this thesis presents the application of CRISPR-Cas9 technique in the production of knockout strains of zebrafish for genes related to AD, currently at the sequencing and detection of mutations on second generation heterozygotes.