Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-01-13T12:57:19Z No. of bitstreams: 1 IvaniBrys_TESE.pdf: 3588483 bytes, checksum: 5c0061be283212e032029bd78a38bd8c (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2016-01-15T14:47:46Z (GMT) No. of bitstreams: 1 IvaniBrys_TESE.pdf: 3588483 bytes, checksum: 5c0061be283212e032029bd78a38bd8c (MD5) / Made available in DSpace on 2016-01-15T14:47:46Z (GMT). No. of bitstreams: 1 IvaniBrys_TESE.pdf: 3588483 bytes, checksum: 5c0061be283212e032029bd78a38bd8c (MD5) Previous issue date: 2014-09-26 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / A Doen?a de Parkinson (DP) est? associada a sintomas motores e ? perda de neur?nios dopamin?rgicos na via nigroestriatal. A prote?na alfa-sinucle?na ? o principal componente dos corpos de Lewy, marcadores biol?gicos da doen?a, e tem sido associada a casos de Parkinson heredit?rio. Recentemente, a estimula??o da medula espinhal (EME) tem se mostrado um m?todo de neuromodula??o efetivo em aliviar os sintomas parkinsonianos em modelos animais e pacientes humanos da DP. Nesse projeto, caracterizamos os efeitos motores e eletrofisiol?gicos da express?o de alfa-sinucle?na na subst?ncia nigra de ratos. Al?m disso, investigamos os efeitos da administra??o de AMPT, L-dopa e da aplica??o de EME nesse modelo. M?todo: Ratos Sprague-Dawley receberam inje??o unilateral de vetor viral vazio ou para expressar alfa-sinucle?na na subst?ncia nigra e foram avaliados semanalmente na tarefa do campo aberto e do cilindro. Um grupo separado de animais implantados com matrizes bilaterais de eletrodos no c?rtex motor e no estriado foram registrados semanalmente no campo aberto, durante as sess?es de EME e nos experimentos farmacol?gicos. Resultados: A express?o de alfa-sinucle?na resultou em assimetria motora, observada na redu??o do uso da pata contralateral na tarefa do cilindro. Os animais apresentaram aumento da atividade de potencial de campo local estriatal em beta ap?s tr?s e quatro semanas de express?o de alfa-sinucle?na, que desapareceu a partir da quinta semana. A administra??o de AMPT resultou em um quadro parkinsoniano severo, com redu??o da atividade locomotora e significativo aparecimento do pico de atividade oscilat?ria em beta no estriado e no cortex desse modelo. A EME mostrou-se efetiva em aliviar a assimetria motora em longo prazo, mas n?o reduziu as oscila??es corticostriatais de baixa frequ?ncia observadas 24 hs ap?s a administra??o de AMPT. Essas oscila??es foram atenuadas pela administra??o de L-dopa que, de forma semelhante ? EME, n?o foi efetiva em restaurar a atividade locomotora dos animais durante esse quadro de deple??o severa de dopamina. Discuss?o: O modelo alfa-sinucle?na da DP reproduz o preju?zo motor e a condi??o progressiva do processo neurodegenerativo. N?s demonstramos, pela primeira vez, que esse modelo apresenta tamb?m aumento da atividade corticostriatal oscilat?ria na banda beta compat?vel com as caracter?sticas da doen?a e que a EME tem efeito terap?utico sobre o sintoma motor desse modelo. / Parkinson disease (PD) is associated with motor symptoms and dopaminergic cell loss in the nigrostriatal pathway. Alpha-synuclein is the major component of the Lewy bodies, the biological hallmarks of disease, and has been associated with familial cases of PD. Recently, the spinal cord stimulation (SCS) showed to be effective to alleviate the Parkinson symptoms in animal models and human patients. In this project, we characterized the motor and electrophysiological effects of alpha-synuclein overexpression in the substantia nigra of rats. We further investigated the effects of spinal electrical stimulation, AMPT and L-dopa administration in this model. Method: Sprague-Dawley rats were injected with empty viral vector or the vector carrying the gene for alpha-synuclein in the substantia nigra, and were tested weekly for 10 weeks in the open field and cylinder tests. A separated group of animals implanted with bilateral electrode arrays in the motor cortex and the striatum were recorded in the open field, during the SCS sessions and the pharmacological experiments. Results: Alpha-synuclein expression resulted in motor asymmetry, observed as the reduction in use of contralateral forepaw in the cylinder test. Animals showed an increase of local field potential activity in beta band three and four weeks after the virus injection, that was not evident after the 5th week. AMPT resulted in a sever parkinsonian state, with reduction in the locomotor activity and significant peak of oscillatory activity in cortex and striatum. SCS was effective to alleviate the motor asymmetry at long term, but did not reduce the corticostriatal low frequency oscillations observed 24 hs after the AMPT administration. These oscillations were attenuated by L-dopa that, even as SCS, was not effective to restore the locomotor activity during the severe dopaminergic depletion period. Discussion: The alpha-synuclein model reproduces the motor impairment and the progressive neurodegenerative process of PD. We demonstrated, by the first time, that this model also presents the increase in low frequency oscillatory activity in the corticostriatal circuit, compatible with parkinsonian condition; and that SCS has a therapeutic effect on motor symptom of this model.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-03-21T11:41:24Z No. of bitstreams: 1 ClarissaLoureiroCampeloBezerra_TESE.pdf: 6936560 bytes, checksum: 72a397096dabf519d649a5db63d55327 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-03-22T15:43:33Z (GMT) No. of bitstreams: 1 ClarissaLoureiroCampeloBezerra_TESE.pdf: 6936560 bytes, checksum: 72a397096dabf519d649a5db63d55327 (MD5) / Made available in DSpace on 2018-03-22T15:43:33Z (GMT). No. of bitstreams: 1 ClarissaLoureiroCampeloBezerra_TESE.pdf: 6936560 bytes, checksum: 72a397096dabf519d649a5db63d55327 (MD5) Previous issue date: 2017-03-14 / Crescentes evidencias indicam que a susceptibilidade gen?tica contribui para a etiologia da doen?a de Parkinson espor?dica (DP). Varia??es gen?ticas no gene SNCA, respons?vel pela codifica??o da alfa-sinucle?na, foram bem estabelecidas atrav?s de estudos de linkage e GWAS. Estudos em todo o mundo encontraram associa??o positiva com polimorfismos de nucleot?deo ?nico (SNPs) no gene SNCA e o aumento do risco para DP. Al?m disto, varia??es no SNCA podem influenciar caracter?sticas ou fen?tipos da DP espor?dica. Este estudo teve como objetivo investigar associa??es entre os SNPs no gene SNCA e a sintomatologia motora e n?o-motora da DP em uma popula??o brasileira. 206 sujeitos (grupo DP= 105 e grupo controle= 101) participaram do estudo. Os pacientes com DP foram recrutados no ambulat?rio de neurologia do Hospital Onofre Lopes, na cidade de Natal (RN). Foram utilizados question?rios e escalas para avaliar o hist?rico de sa?de, fatores ambientais, aspectos motores (Hoehn & Yarh e Unified Parkinson?s Disease Rating Scale), funcionais (Schwab & England), cognitivos (Bateria de Avalia??o Frontal e Mini-Exame do Estado Mental) e emocionais (Invent?rio de Depress?o de Beck e Inventario de Ansiedade de Beck) dos participantes. Tamb?m foi coletada uma amostra de sangue para a realiza??o da extra??o do DNA e posterior genotipagem dos SNPs rs11931074, rs356219, rs2583988, rs2736990. Quanto a avalia??o cl?nica, o grupo DP apresentou comprometimento motor de moderado a severo associado a uma moderada redu??o da capacidade funcional. Os d?ficits cognitivos foram mais presentes nos sujeitos com baixa escolariza??o. Os sintomas depressivos e ansiosos foram evidenciados com maior frequ?ncia e gravidade no grupo DP. Os dados da genotipagem mostraram todos os SNP mais frequentes no grupo DP, e a associa??o dos SNPs rs356219, rs2583988, rs2736990 aumentando o risco para DP foi confirmada. Tamb?m foi encontrada uma associa??o dos alelos de risco com a DP de in?cio precoce. T-rs2583988, G-rs356219 e C-2736990 foram significativamente mais frequentes nos pacientes com altera??es cognitivas quando comparados aos controles com a mesma condi??o. Al?m disto, a presen?a de altera??es cognitivas foi mostrou-se um fator preditivo para a DP em um modelo de regress?o log?stica. Este estudo ? o primeiro a demonstrar a associa??o de polimorfismos no gene SNCA em uma popula??o da Am?rica do Sul. / Increasing evidence indicate that genetic susceptibility contributes to the etiology of sporadic Parkinson?s Disease (PD). Genetic variations in SNCA gene, which encodes alpha-synuclein protein, are already well established in linkage and GWAS studies. Worldwide studies have find positive association of single nucleotide polymorphism (SNP) in SNCA and the increase risk for PD. In addition, variants in SNCA can influence individual traits or phenotypes of sporadic PD. The present study investigated associations between SNPs in SNCA gene and motor and non-motor symptoms of PD in a Brazilian population. 206 subjects (PD group= 105 and Control group = 101) participated in this study. The patients with PD were recruited from the neurology clinic of Onofre Lopes University Hospital, in Natal (RN, Brazil). We used questionnaires and scales to evaluate the healthy history, environmental factors, motor (Hoehn & Yarh e Unified Parkinson?s Disease Rating Scale), functional (Schwab & England), cognitive (Frontal Assessment Battery and Mini Mental State Examination) and emotional (Beck Depression Inventory and Beck Anxiety Inventory) aspects of the subjects. We also collected a blood sample to DNA extraction and genotyping of SNPs rs11931074, rs356219, rs2583988 and rs2736990. Regarding clinical assessment, the PD group presented motor impairment associated to a moderate decrease of functional capacity. The cognitive impairments were more evident in individuals with low education. Depressive and anxiety symptoms had a higher frequency and severity in PD group. All SNPs were more frequent in PD patients (p<0.05), and the associations of SNPs rs2583988, rs356219 and rs2736990 with increased PD risk were confirmed. The G-rs356219 and C-rs2736990 alleles had a significant higher frequency in patients with early onset PD. T-rs2583988, G-rs356219 and C-2736990 risk alleles were significantly more frequent in PD patients with cognitive impairments than controls in this condition. Furthermore, the presence of cognitive impairment was a predictor for PD in a logistic regression model. This study demonstrated for the first time an association of SNCA polymorphisms and PD in a South-American sample.