Study of mitochondrial dysfunction mechanisms in Huntington's disease striatal degeneration

[eng] Huntington's disease (HD) is an autosomal-dominant inherited neurodegenerative disorder, characterized by progressive behavioral, motor and cognitive deficits (HDCRG, 1993; Ross & Margolis, 2001). The predominant neuropathological hallmark of HD is the selective loss of medium spiny n...

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Detalles Bibliográficos
Autor: Cherubini, Marta
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2016
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/105379
Acceso en línea:https://hdl.handle.net/2445/105379
http://hdl.handle.net/10803/398895
Access Level:acceso abierto
Palabra clave:Corea de Huntington
Malalties neurodegeneratives
Huntington's chorea
Neurodegenerative Diseases
Descripción
Sumario:[eng] Huntington's disease (HD) is an autosomal-dominant inherited neurodegenerative disorder, characterized by progressive behavioral, motor and cognitive deficits (HDCRG, 1993; Ross & Margolis, 2001). The predominant neuropathological hallmark of HD is the selective loss of medium spiny neurons within the striatum that extends to other brain regions with the progression of the disease (Martin & Gusella, 1986). Although mutant huntingtin (mHtt) represents a key factor in the pathogenesis of the disease, the molecular mechanisms underlying the preferential vulnerability of the striatum to mHtt toxicity remain unclear. Compelling evidence suggest that mitochondrial defects may play a crucial role in the disease, however, it is still debated whether mitochondrial dysfunction represents just an epiphenomenon of the cellular degeneration or it has an actual pathogenic role. In this Thesis, the general purpose was to identify possible mitochondrial impaired mechanisms and to investigate their role in the selective striatal vulnerability of HD, in order to provide important insights for the development of new therapeutic strategies. The first aim was to clarify whether mitochondrial injuries perpetrate the dopaminergic neurotoxicity in HD striatal degeneration. Since Cdk5 has been proposed as a critical regulator of mitochondrial fission (Meuer et al., 2007) and as a deleterious player in the striatal vulnerability upon dopamine signalling (Paoletti et al., 2008), we hypothesize a new detrimental role for Cdk5 in HD pathology by mediating dopaminergic neurotoxicity through deregulation of mitochondrial dynamic processes. On the other hand, several studies have proposed mitochondrial Ca mishandling as a component of Ca controversial and a conclusive cause remains uncertain. We propose that the propensity of mitochondria to undergo fragmentation in HD could result in the disruption of ER-mitochondria contacts, which are essential for the proper buffering of Ca whether defects in ER-mitochondria associated membranes could be responsible for the alteration of mitochondrial Ca handling in HD. dyshomeostasis in HD. However, the results appear 2+ 2+ by mitochondria. Therefore, the second aim of this study was to investigate.