Autor(es):
Vieira, Pedro Miguel de Sousa 
; Marques, Belém Sampaio ; Ludovico, Paula ; Dias, Alberto Carlos Pires
Data: 2011
Identificador Persistente: http://hdl.handle.net/1822/18575
Origem: RepositóriUM - Universidade do Minho
Assunto(s): Hypericum perforatum; Toxicity; α-synuclein
Descrição
Parkinson’s disease (PD) is a neurodegenerative disorder with high prevalence and is
characterized by the loss of dopaminergic neurons and the presence of cytoplasmic
eosinophilic inclusions named Lewy bodies, in which α-synuclein is the major
constituent. Several studies implicate abnormal protein accumulation, protein
phosphorylation, mitochondrial dysfunction and oxidative stress as common pathways
implicated in PD pathogenesis. Polyphenolic compounds are commonly found in both
edible and medicinal plants, and they have been reported to have multiple biological
effects, including antioxidant activity. The budding yeast Saccharomyces cerevisiae has
been used as a model to study several neurodegenerative diseases, including biological
function of α-synuclein, as well as its toxicity. The heterologous expression of wild-type
and A53T mutant form of α-synuclein causes toxicity in cells. Therefore, the aim of this
study was to evaluate the possible protective effect of Hypericum perforatum phenolic
compounds (quercetin, kaempferol and biapigenine), in the toxicity induced by the
heterologous expression of α-synuclein, using the yeast Saccharomyces cerevisiae as a
model. Preliminary results indicate that the presence of these phenolic compounds
decrease the toxicity observed in cells expressing α-synuclein without the presence of
the compounds. We concluded that these phenolic compounds apparently have
beneficial biological properties that consequently could have a potential use in
preventing Parkinson’s disease.
