Orientadora: Prof. Dra. Giselle Cerchiaro / Tese (doutorado) - Universidade Federal do ABC. Programa de Pós-Graduação em Ciência e Tecnologia/Química, 2017. / Fortes evidencias sugerem que a deterioracao da homeostase de metais essenciais,
o aumento de danos oxidativos a biomoleculas e o aumento de especies oxidantes
estao estreitamente relacionados ao desencadeamento, manutencao e evolucao do
quadro de algumas doencas neurodegenerativas como Alzheimer, Parkinson e
eslerose lateral amiotrofica. Apesar desta relacao estar bem estabelecida, ainda e
desconhecida quais os mecanismos metabolicos relacionados a tais patologias.
Tratando de diferentes doencas neurodegenerativas, com origens e mecanismos
diversos, para que se possa propor uma prevencao e/ou tratamento para pacientes
acometidos por sintomas seriamente debilitantes, e necessario fazer uma analise
multidimensional, relacionando dados quimicos e comportamentais. Este trabalho
mostrou os efeitos deleterios da inducao do estresse oxidativo por dois tratamentos
diferentes (H2O2 e ¿À-amiloide na forma oligomerica) em linhagens celulares
relacionadas ao sistema nervoso central (NSC-34, mHipoE-18, SH-SY5Y
diferenciada e astrocitos imortalizados). Os dois tratamentos foram capazes de
induzir o aumento da fosforilacao da proteina Tau, fator esse que esta diretamente
ligado a doencas neurodegenerativas. De forma isolada, foram planejados
experimentos que oferecem uma leitura da relacao dos danos celulares causados
pelo fluxo de elementos essenciais (Fe, Cu, Zn, Ca, Se, Co, Mn, Mg e Cr) e os
danos a biomoleculas (peroxidacao lipidica, carbonilacao de proteinas e danos ao
DNA). O fluxo de elementos essenciais ocasionado por danos oxidativos nas
mitocondrias e no nucleo foram analisados separadamente, bem como o efeito dos
diferentes elementos essenciais na celula integra. Como era esperado, cada
tratamento levou a mecanismos de resposta distintos para cada linhagem celular. No
tempo de 24 h os dois tratamentos induziram danos ao DNA para todas as linhagens
celulares estudadas. Ja para a peroxidacao lipidica, o tratamento com H2O2
danificou lipideos da linhagem SHSY5Y e diminuiu os danos lipidicos para a
linhagem de astrocitos imortalizados enquanto que o tratamento com A¿ÀO so
aumentou a peroxidacao lipidica para as celulas da linhagem NSC-34. Alem disso, o
tratamento de H2O2 induziu danos proteinas nas celulas das linhagens NSC-34 e
SHSY5Y, enquanto que o tratamento com A¿ÀO induziu um aumento dos danos a
proteinas nas celulas da linhagem NSC-34 e uma diminuicao destes danos nas
celulas SH-SY5Y. O tratamento com H2O2 induziu o aumento de Zn e Co e uma
diminuicao de Mg e Se no nucleo; diminuicao de Zn, Ca, Se e Mn na mitocondria e
diminuicao de Zn, Mn e Mg em celulas da linhagem NSC-34. Em celulas da
linhagem SH-SY5Y o tratamento com H2O2 induziu o aumento de Ca na celula total,
aumento de Co e diminuicao de Ca no nucleo e aumento de Fe, Zn e Ca na
mitocondria. De modo geral, podemos observar um aumento do fluxo de Fe em
todas as linhagens submetidas aos tratamentos oxidativos. Verificamos que o
aumento de Co no nucleo pode ser utilizado como um biomarcador do efeito
deleterio do estresse oxidativo induzido por H2O2 por aparecer como resposta a este
tratamento em todas as linhagens estudadas nesse trabalho. Entretanto para o
tratamento com A¿ÀO nenhum biomarcador foi encontrado uma vez que as diferentes
linhagens estudadas tiveram alteracoes na homeostase de elementos de maneira
distinta. / Strong evidence suggests that the deterioration of essential metal homeostasis,
increased oxidative damage to biomolecules, and increased oxidant species are
closely related to the onset, maintenance, and evolution of neurodegenerative
diseases such as Alzheimer's, Parkinson's, and Amyotrophic lateral sclerosis.
Although this relationship is well established, the underlying metabolic mechanisms
behind these pathologies remains unknown. To develop appropriate treatments for
different neurodegenerative diseases with diverse origins and mechanisms, so that a
prevention and/or treatment can be proposed for patients suffering from severely
debilitating symptoms, it is necessary to perform a multidimensional analysis, relating
chemical, metabolomic and behavioral data. This study makes an essential
contribution to this field, as we have collected relevant data on the deleterious effects
of oxidative stress induction by two different treatments (H2O2 and AâO) on cell lines
related to the central nervous system (NSC-34, mHipoE-18, differentiated SH-SY5Y
and immortalized astrocytes). Both oxidative treatments demonstrated the ability to
induce an increase in Tau phosphorylation, a factor that is directly related to
neurodegenerative disease. Experiments were carried out in isolation to evaluate the
relationship between cellular damage caused by the flow of essential elements (Fe,
Cu, Zn, Ca, Se, Co, Mn, Mg, and Cr) and damage to biomolecules (lipid peroxidation,
Carbonylation of proteins and DNA damage). The flow of essential elements caused
by oxidative damage in the mitochondria and nucleus were analyzed separately, as
well as the effect of different essential elements within the whole cell. As expected,
each treatment led to distinct response mechanisms for each cell line. At 24 h, both
treatments induced DNA damage for all cell lines studied. Analyzing lipid
peroxidation, treatment with H2O2 increased lipid damage to the SHSY5Y cell line
strain and decreased lipid damage to the immortalized astrocyte lineage, whereas Aâ
treatment only increased lipid peroxidation for NSC-34 cells. In addition, H2O2
treatment induced protein damage in NSC-34 and SHSY5Y cell lines, whereas AâO
treatment induced an increase in protein damage in NSC-34 lineage cells and a
decrease in damage to SH-SY5Y cell line. Treatment with H2O2 induced increased
Zn and Co and decreased Mg and Se in the nucleus, decreased Zn, Ca, Se and Mn
in the mitochondria and decreased Zn, Mn, and Mg in NSC-34 lineage cells. In cells
from the SH-SY5Y line, treatment with H2O2 induced the increase of Ca in the total
cell, an increase in Co and a decrease in Ca of the nucleus, and the increase of Fe,
Zn and Ca in mitochondria. For cells of the immortalized astrocyte line, when treated
with H2O2 there was an increase of Fe in the total cell, an increase of Cu, Co and Cr
in the nucleus and increased Fe and Cu in mitochondria. However, Aâ treatment to
cells of the NSC-34 lineage induced a decrease in Mn and Mg in the total cell, an
increase of Fe, Cu, Zn, Ca and Cr in the nucleus and a decrease of Ca, Se and Mn in
mitochondria. In cells from the SH-SY5Y strain, AâO treatment induced increased Fe
and Ca in the total cell, decreased Ca in the nucleus and increased Fe, Cu, Zn, Ca,
Se and Co in the mitochondria. Finally, for immortalized astrocytic lineage cells
treated with AâO, there was increased Fe and Cr both in the total cell and the
nucleus, and increased Fe in mitochondria. In this way, we verified that increased Co
in the nucleus can be used as a biomarker of the deleterious effects of H2O2 induced
oxidative stress, as all cell lines displayed a convergent response. However, no such
biomarker could be identified for treatment with AâO, as the elemental homeostatic
responses observed were varied across different cell lines.
| Identifer | oai:union.ndltd.org:IBICT/oai:BDTD:108539 |
| Date | January 2017 |
| Creators | Lago, Larissa Cristina Carvalho do |
| Contributors | Cerchiaro, Giselle, Maltez, Heloisa França, Rocha, Diogo Librandi da, Prado, Fernanda Manso, Naozuka, Juliana |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/doctoralThesis |
| Format | application/pdf, 206 f. : il. |
| Source | reponame:Repositório Institucional da UFABC, instname:Universidade Federal do ABC, instacron:UFABC |
| Rights | info:eu-repo/semantics/openAccess |
| Relation | http://biblioteca.ufabc.edu.br/index.php?codigo_sophia=108539&midiaext=75338, http://biblioteca.ufabc.edu.br/index.php?codigo_sophia=108539&midiaext=75339, Cover: http://biblioteca.ufabc.edu.brphp/capa.php?obra=108539 |
Page generated in 0.003 seconds