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Efeitos de um programa de dança e de caminhada na marcha e na qualidade de vida de indivíduos com doença de ParkinsonDelabary, Marcela dos Santos January 2018 (has links)
Introdução: A doença de Parkinson (DP), caracterizada por ser crônica, progressiva e neurodegenerativa, é uma das enfermidades neurológicas mais frequentes na atualidade. Pacientes com DP apresentam prejuízos motores, como rigidez muscular, tremor de repouso, lentidão de movimentos, instabilidade postural, e alterações na marcha e no equilíbrio; e distúrbios não-motores, como fatores cognitivos e neuropsiquiátricos, depressão, e uma consequente diminuição da qualidade de vida (QV). Apesar de a caminhada ser considerada tradicionalmente uma recomendação médica no tratamento não farmacológico da DP, a dança vem surgindo como uma importante ferramenta no tratamento complementar destes pacientes, quando somada a terapias medicamentosas tradicionais. Objetivo: Verificar e comparar os efeitos de um programa de dança e de caminhada na mobilidade funcional, nos parâmetros motores e na QV de pessoas com DP. Métodos: foi elaborado um protocolo de aulas de dança inspirado em ritmos musicais brasileiros: forró e samba. A amostra foi composta por 18 participantes com DP, divididos de forma não randomizada, em dois grupos: grupo dança (GD; n = 12) e grupo caminhada (GC; n = 6), expostos a 24 aulas de dança ou caminhada, com duração de uma hora e frequência de duas vezes por semana. Os instrumentos de coletas de dados utilizados foram uma ficha de dados pessoais dos pacientes, a Escala de Hoehn e Yahr (H&Y), o teste Timed Up and Go (TUG), a parte motora da Escala Unificada de Avaliação da DP (UPDRS III), o Índice de reabilitação (IR), a análise cinemática da caminhada e o Parkinson Disease Questionnaire (PDQ-39). A normalidade dos dados descritivos no momento inicial da pesquisa foi verificada através do Teste Shapiro-Wilk, foi utilizado o Teste Wilcoxon para dados não paramétricos e o Teste t pareado para dados paramétricos. Para os desfechos da pesquisa foram utilizados a análise de Equações de Estimativas Generalizadas (GEE), para a comparação entre os grupos GD e GC, os tempos PRÉ e PÓS intervenção, e interação tempo*grupo. Foi utilizado um posthoc de Bonferroni, para identificar as diferenças entre as médias em todas as variáveis. Para a análise dos dados foi utilizado o software Statistical Package for Social Sciences (SPSS) versão 20.0. O nível de significância adotado para ambos os testes foi de α<0,05. Resultados: Foi realizado um protocolo detalhado das intervenções. Os dois grupos apresentaram melhorias significativas após a intervenção em relação a mobilidade funcional na velocidade autosselecionada (VAS) (p = 0,02) e na velocidade rápida (VR) (p = 0,02), ao tempo de contato (TC) (perna esquerda VAS, p = 0,0028; perna direita VR, p = 0,009; perna esquerda, VR p = 0,025), ao tempo de balanço (TB) (perna esquerda VAS, p = 0,0028), a fase de duplo apoio (FDA) (perna direita VR, p < 0,001), a QV geral (p = 0,004), e aos domínios de bemestar emocional (p = 0,001), cognição (p = 0,020) e desconforto corporal (p = 0,008). O GD apresentou melhores resultados em comparação com o GC para os desfechos de Frequência de passos (FP) (p = 0,011) e o domínio de atividades de vida diária (AVDs) (p = 0,049). Conclusão: Ambos os grupos, GD e GC, apresentaram melhorias significativas após o período de intervenção, demonstrando que a dança é tão eficiente quanto a caminhada para a mobilidade funcional, parâmetros motores e a qualidade de vida de indivíduos com DP. / Background: Parkinson's disease (PD), characterized as progressive and neurodegenerative, is one of the most frequent neurological diseases of the present time. Patients with PD present motor impairment, such as muscle stiffness, rest tremor, slow movements, postural instability, and gait and balance alterations; And non-motor factors, such as cognitive and neuropsychiatric disorders, depressive symptoms, and a consequent decrease in quality of life (QL). Although walking is traditionally considered a medical recommendation in the non-pharmacological treatment of PD, dance has emerged as an important tool in the complementary treatment of these patients when added to traditional drug therapies.Objective: Verify and compare the effects of a program of dance and walking in functional mobility, motor parameters and QL of people with PD. Methods: the sample was composed of 18 participants with PD, divided into two non-randomized groups: dance group (DG; n = 12) and walking group (WG; n = 6). The data collection instruments used were be a personal data sheet of the patients, the Hoehn and Yahr Scale (HY), the Timed Up and Go test (TUG), the motor part of the Unified PD Rating Scale (UPDRS III), locomotor rehabilitation index (LRI), the kinematic walk analysis and the Parkinson's Disease Questionnaire (PDQ- 39). The normality of the descriptive data at the initial time of the research was verified through the Shapiro-Wilk Test, using the Wilcoxon Test for non-parametric data and the paired t-test for parametric data. For the research outcomes, the Generalized Estimating Equations (GEE) analysis was used to compare the GD and GC groups, the pre and post intervention moments, and the time group interaction. A Bonferroni post-hoc was used to identify the differences between means in all variables. Statistical Package for Social Sciences (SPSS) software version 20.0 was used to analyze the data. The significance level adopted for both tests was α <0.05. Results: A detailed protocol of interventions was performed. The two groups showed significant improvements after the intervention in relation to functional mobility in comfortable velocity (CV) (p = 0.02) and in fast velocity (FV) (p = 0.02), at stance time (StT) (Left leg CV, p = 0.0028); right leg FV, p = 0.009; left leg, FV p = 0.025), and swing time (SwT) (left leg CV, p = 0,0028), at double support phase (DSF) (rigth leg FV, p < 0,001), a general QL (p = 0,004), and to emotional well-being (p = 0.001), cognition (p = 0.020) and body discomfort (p = 0.008). The DG presented better results in comparison to the WG for the outcomes of Frequency of steps (FS) (p = 0.011) and the domain of activities of daily living (ADLs) (p = 0.049). The two interventions showed significant improvements regarding functional mobility, time of contact (TC), time of balance (TB), the perception of general QL, and domains of emotional well-being, cognition and body discomfort. The DG presented better results compared to the WG for the step frequency, double support phase and the domain of daily living activities. Conclusion: Both groups, DG and WG, showed significant improvements after the intervention period, demonstrating that dance is as efficient than walking for functional mobility, motor parameters and the QL for individuals with PD.
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Estudo genético da doença de Parkinson / Genetical study of Parkinsons diseaseFen, Chien Hsin 05 April 2007 (has links)
A doença de Parkinson (DP) é a segunda doença neurodegenerativa mais comum com uma prevalência aproximada de 3% em pacientes com mais de 64 anos. A doença é esporádica, mas o parkinsonismo primário (PP) familiar, decorrente de defeitos genéticos específicos, tem sido encontrado em cerca de 10% dos casos diagnosticados como DP. Os objetivos deste trabalho são analisar o DNA de pacientes com PP acompanhados no ambulatório do Grupo de Estudo de Distúrbios do Movimento da Clínica Neurológica do Hospital das Clínicas da FMUSP que apresentam início precoce (< 40 anos) ou história familiar positiva com o intuito de rastrear mutações responsáveis pela doença e descrever as características clínicas desse grupo de pacientes e dos familiares acometidos. Entre Janeiro de 2004 a Janeiro de 2006 foram selecionados 53 probandos com PP, sendo que 29 eram esporádicos, 16 com história familiar sugestiva de herança autossômica dominante (AD) e 8 com história familiar sugestiva de herança de autossômica recessiva (AR). No total, 100 amostras de DNA foram coletadas, 70 de pacientes ou familiares com PP, 1 com parkinsonismo secundário ao uso de neuroléptico e o restante de familiares sem PP. Dos casos afetados, 45 eram do sexo masculino e 25 feminino, a idade média de início dos sintomas foi de 38,3 anos (10-72) e a média de idade no momento da investigação foi de 49,8 anos (22-72). Todos apresentaram instalação assimétrica do quadro, curso lento e progressivo e boa resposta ao tratamento com levodopa ou agonista dopaminérgico. Pacientes com padrão de herança AD foram testados para a mutação Gli2019Ser que é o defeito mais comum do gene LRRK2 (PARK8) sendo encontradas duas famílias afetadas. A análise mutacional dos genes PARK6 e PARK7 está em andamento. Todos os casos esporádicos e com padrão de transmissão AR foram testados para mutações do gene PARK2 e foram encontradas as seguintes mutações homozigóticas em 4 famílias: 255delA, deleção de exon 3-4, deleção do exon 2-3 e uma nova mutação IVS1+1G/T. Num paciente com parkinsonismo juvenil (idade de início dos sintomas <21 anos) foi encontrada uma nova mutação homozigótica no gene ATP13A2 (PARK9) no exon 15 que determina a substituição Gli504Arg na proteína codificada. Em grande parte dos casos estudados os achados genéticos e clínicos são similares aos descritos na literatura. Entretanto, encontramos novas mutações do gene PARK2 e PARK9 e no paciente com a mutação ATP13A2 os achados clínicos diferem em alguns aspectos da descrição clássica. / Parkinson disease (PD) is the second most common neurodegenerative disorder affecting approximately 3% of the population over age 64. Most cases of PD manifest in sporadic form, but familial primary parkinsonism (PP) due to specific genetical abnormalities has been found in about 10% of cases diagnosed as PD. The aims of this study were to analyze the DNA of PP patients seen at the Group for the Study of Movement Disorders of the Neurology Department of Hospital das Clinicas of the University of São Paulo who presented early onset of the disease (< 40 years of age) or positive family history, with the purpose of screening possible candidate mutations for the disease, and to describe the clinical features of this group of patients and affected members of their families. Between January 2004 and January 2006, 53 probands were selected of whom, 29 were sporadic cases, 16 had probable autosomical dominant (AD) pattern of inheritance, and 8 autosomical recessive (AR). In total 100 samples of DNA were collected, 70 from PP patients or affected relatives, one case with neuroleptic-induced parkinsonism, and the rest from not affected members. Forty five affected individuals were men and 25 women, the median age of the symptoms onset was 38.3 years (10-72), and the median age at the moment of the examination was 49.8 years (22-72). All patients had asymmetric installation of the disease, slow progression of the PP, and good response to levodopa or dopaminergic agonist therapy. Patients with AD inheritance were screened for Gly2019Ser mutation, which is the most common defect in PD due to LRRK2 gene, and two families carried this mutation. The screening of PARK6 and PARK7 is ongoing. All sporadic and AR inheritance cases were tested for mutation of (PARK2) and the following mutation were found in 4 families in homozygous state: 255delA, exon 3-4 deletion, exon 2-3 deletion, and a novel mutation IVS1+1G/T. In a juvenile parkinsonism proband (age of onset < 21 years) a novel missense homozygous mutation in ATP13A2 (PARK9) gene was found in exon 15 which resulted the Gly504Arg change in the encoded protein. In general the genetical and clinical findings of this series of patients are similar to those reported in the literature, although novel mutation in PARK2 and PARK9 were obtained. Some clinical features of the patient with ATP13A2 mutation differed from the classical descriptions.
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Efeito neuroprotetor do Carvacrol em dois modelos experimentais da Doença de Parkinson: evidências comportamentais e imunohistoquímicas / Neuroprotective effect of Carvacrol in two rat models of Parkinson’s disease: behavioral and immunohistochemical evidencesLins, Lívia Cristina Rodrigues Ferreira 23 January 2017 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Parkinson’s disease (PD) is a neurodegenerative disease characterized by a progressive degeneration of dopaminergic neurons in the Substantia Nigra pars compact (SNpc) with consequent depletion of dopamine in the striatum, which gives rise to characteristic motor symptoms of PD. Although its etiology of is unknown, several studies have been suggested that oxidative stress and inflammation play a critical function in the physiopathology of PD and antioxidant and ani-inflammatory agents could be helpful to slown down the dopaminergic neurodegeneration. Thus, many studies have evaluated the potential neuroprotective effect of these agentes, including Carvacrol (CA). CA is a phenolic monoterpene found in essential oils of many aromatic plants and it has a variety of pharmacological effects on Central Nervous System, including antioxidant and anti-inflammatory activities. In this context, the objective of this study was to investigate a possible neuroprotective effect of CA in two rat models of PD. Two experiments were performed: in the experiment I, male Wistar rats were submitted to repeated administration of a low dose (0.1 mg/kg, s.c.) of reserpine (RES) or vehicle of reserpine (VR) and concomitantly treated with CA at doses of 12.5 or 25 mg/kg (i.p.) or vehicle of carvacrol (VC). Across the treatment, the animal motor behavior was evaluated by catalepsy test, open field test and assessment of oral movements. In the experiment II, male Long-Evans rats were pretreated for seven days with CA at doses of 50 or 100 mg/kg (i.p.) or VC, and were then submitted to unilateral injection of 6-hydroxydopamine (6-OHDA) or vehicle of 6-OHDA into the medial forebrain bundle (MFB). The animals were treated with CA or VC for three weeks after injection. Thereafter, they were assessed for motor behavioral function by open field, cylinder test, rotarod and amphetamine-induced circling test. In both experiments, upon completion behavioral tests, rats were perfused and theirs brains were subjected for tyrosine hydroxylase (TH) immunohistochemical analysis. In the experiment I, the results showed that the CA treatment, in both doses 12.5 e 25 mg/kg, was able to prevent the catalepsy behavior and the development of vacuous chewing movements induced by RES, however, CA failed to revert the decreased locomotor activity induced by RES in the open field test. In addition, CA in both doses prevented the depletion of TH immunostaining induced by RES in the SNpc and dorsal striatum. In the experiment II, the treatment with CA at dose of 50 mg/kg prevented the motor deficits induced by 6-OHDA injection in the open field test, cylinder test and rotarod, and increased the number of rotations induced by amphetamine. Moreover, CA attenuated the dopaminergic neurons damage in the SNpc and dorsal striatum induced by 6-OHDA injection. Taken together, our results suggest that CA shows neuroprotective effect, preventing or attenuating motor and neurochemical impairments induced by RES and 6-OHDA, so it may be regarded a promising therapeutic candidate for the prevention or treatment of PD. / A Doença de Parkinson (DP) é uma doença neurodegenerativa caracterizada por uma degeneração progressiva de neurônios dopaminérgicos da Substância Negra parte compacta (SNpc), o que resulta nas alterações motoras características desta patologia. Embora sua etiologia ainda permaneça desconhecida, vários estudos indicam que o estresse oxidativo e a inflamação exercem uma função crítica na fisiopatologia da DP e agentes antioxidantes e anti-inflamatórios poderiam desacelerar a neurodegeneração dopaminérgica. Assim, tem sido crescente o número de pesquisas relacionadas a investigação do potencial neuroprotetor destes agentes, entre eles, o Carvacrol (CA). O CA é um monoterpeno fenólico encontrado nos óleos essenciais de diversas plantas aromáticas e apresenta uma variedade de atividades farmacológicas sobre o Sistema Nervoso Central, incluindo atividades antioxidante e anti-inflamatória. Neste contexto, o objetivo deste estudo foi investigar um possível efeito neuroprotetor do CA em ratos submetidos a dois modelos de DP. Foram realizados dois experimentos: no experimento I, ratos Wistar foram submetidos a administração repetida de uma dose baixa (0,1 mg/kg, s.c.) de reserpina (RES) ou veículo da reserpina (VR) e tratados concomitantemente com CA nas doses de 12,5 ou 25 mg/kg (i.p.) ou com o veículo do carvacrol (VC). Ao longo do experimento, os animais tiveram seu comportamento motor avaliado através dos testes de catalepsia, campo aberto e avaliação dos movimentos orais. No experimento II, ratos Long-Evans foram pré-tratados por sete dias com CA nas doses de 50 ou 100 mg/kg (i.p.) ou VC, e então foram submetidos a uma injeção unilateral de 6-hidroxidopamina (6-OHDA) ou veículo no feixe prosencefálico medial (medial forebrain bundle -MFB). Os animais foram tratados com CA ou VC por três semanas após a injeção de 6-OHDA e após este período tiveram seu comportamento motor avaliado através dos testes do campo aberto, cilindro, rotarod e rotações induzidas por anfetamina. Em ambos os experimentos, ao fim dos testes comportamentais, os animais foram perfundidos e seus cérebros foram processados para imunohistoquímica para tirosina hidroxilase (TH). No experimento I, os resultados mostraram que o CA em ambas as doses (12,5 e 25 mg/kg) preveniu o comportamento de catalepsia e o desenvolvimento de movimentos de mastigação no vácuo induzidos pela RES, porém não reverteu a redução da atividade locomotora causada pela RES no teste do campo aberto. O CA em ambas as doses preveniu a redução da marcação de TH induzida pela RES na SNpc e no estriado dorsal. No experimento II, os resultados mostraram que o CA na dose de 50 mg/kg preveniu os déficits motores induzidos pela injeção de 6-OHDA nos testes do campo aberto, cilindro e rotarod, e aumentou o número de rotações induzidas por anfetamina. Além disso, o CA atenuou o dano provocado pela injeção de 6-OHDA nos neurônios dopaminérgicos da SNpc e estriado dorsal. Os resultados obtidos no presente estudo sugerem que o CA apresenta um efeito neuroprotetor, prevenindo ou atenuando as alterações motoras e neuroquímicas induzidas pela RES e 6-OHDA. Desta forma, o CA pode ser considerado um candidato terapêutico promissor para a prevenção ou tratamento da DP.
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Estudo genético da doença de Parkinson / Genetical study of Parkinsons diseaseChien Hsin Fen 05 April 2007 (has links)
A doença de Parkinson (DP) é a segunda doença neurodegenerativa mais comum com uma prevalência aproximada de 3% em pacientes com mais de 64 anos. A doença é esporádica, mas o parkinsonismo primário (PP) familiar, decorrente de defeitos genéticos específicos, tem sido encontrado em cerca de 10% dos casos diagnosticados como DP. Os objetivos deste trabalho são analisar o DNA de pacientes com PP acompanhados no ambulatório do Grupo de Estudo de Distúrbios do Movimento da Clínica Neurológica do Hospital das Clínicas da FMUSP que apresentam início precoce (< 40 anos) ou história familiar positiva com o intuito de rastrear mutações responsáveis pela doença e descrever as características clínicas desse grupo de pacientes e dos familiares acometidos. Entre Janeiro de 2004 a Janeiro de 2006 foram selecionados 53 probandos com PP, sendo que 29 eram esporádicos, 16 com história familiar sugestiva de herança autossômica dominante (AD) e 8 com história familiar sugestiva de herança de autossômica recessiva (AR). No total, 100 amostras de DNA foram coletadas, 70 de pacientes ou familiares com PP, 1 com parkinsonismo secundário ao uso de neuroléptico e o restante de familiares sem PP. Dos casos afetados, 45 eram do sexo masculino e 25 feminino, a idade média de início dos sintomas foi de 38,3 anos (10-72) e a média de idade no momento da investigação foi de 49,8 anos (22-72). Todos apresentaram instalação assimétrica do quadro, curso lento e progressivo e boa resposta ao tratamento com levodopa ou agonista dopaminérgico. Pacientes com padrão de herança AD foram testados para a mutação Gli2019Ser que é o defeito mais comum do gene LRRK2 (PARK8) sendo encontradas duas famílias afetadas. A análise mutacional dos genes PARK6 e PARK7 está em andamento. Todos os casos esporádicos e com padrão de transmissão AR foram testados para mutações do gene PARK2 e foram encontradas as seguintes mutações homozigóticas em 4 famílias: 255delA, deleção de exon 3-4, deleção do exon 2-3 e uma nova mutação IVS1+1G/T. Num paciente com parkinsonismo juvenil (idade de início dos sintomas <21 anos) foi encontrada uma nova mutação homozigótica no gene ATP13A2 (PARK9) no exon 15 que determina a substituição Gli504Arg na proteína codificada. Em grande parte dos casos estudados os achados genéticos e clínicos são similares aos descritos na literatura. Entretanto, encontramos novas mutações do gene PARK2 e PARK9 e no paciente com a mutação ATP13A2 os achados clínicos diferem em alguns aspectos da descrição clássica. / Parkinson disease (PD) is the second most common neurodegenerative disorder affecting approximately 3% of the population over age 64. Most cases of PD manifest in sporadic form, but familial primary parkinsonism (PP) due to specific genetical abnormalities has been found in about 10% of cases diagnosed as PD. The aims of this study were to analyze the DNA of PP patients seen at the Group for the Study of Movement Disorders of the Neurology Department of Hospital das Clinicas of the University of São Paulo who presented early onset of the disease (< 40 years of age) or positive family history, with the purpose of screening possible candidate mutations for the disease, and to describe the clinical features of this group of patients and affected members of their families. Between January 2004 and January 2006, 53 probands were selected of whom, 29 were sporadic cases, 16 had probable autosomical dominant (AD) pattern of inheritance, and 8 autosomical recessive (AR). In total 100 samples of DNA were collected, 70 from PP patients or affected relatives, one case with neuroleptic-induced parkinsonism, and the rest from not affected members. Forty five affected individuals were men and 25 women, the median age of the symptoms onset was 38.3 years (10-72), and the median age at the moment of the examination was 49.8 years (22-72). All patients had asymmetric installation of the disease, slow progression of the PP, and good response to levodopa or dopaminergic agonist therapy. Patients with AD inheritance were screened for Gly2019Ser mutation, which is the most common defect in PD due to LRRK2 gene, and two families carried this mutation. The screening of PARK6 and PARK7 is ongoing. All sporadic and AR inheritance cases were tested for mutation of (PARK2) and the following mutation were found in 4 families in homozygous state: 255delA, exon 3-4 deletion, exon 2-3 deletion, and a novel mutation IVS1+1G/T. In a juvenile parkinsonism proband (age of onset < 21 years) a novel missense homozygous mutation in ATP13A2 (PARK9) gene was found in exon 15 which resulted the Gly504Arg change in the encoded protein. In general the genetical and clinical findings of this series of patients are similar to those reported in the literature, although novel mutation in PARK2 and PARK9 were obtained. Some clinical features of the patient with ATP13A2 mutation differed from the classical descriptions.
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Μελέτη των υπομονάδων των υποδοχέων διεγερτικών και ανασταλτικών αμινοξέων στον εγκέφαλο ενός γενετικού μοντέλου της νόσου Parkinson / Study of excitatory and inhibitory aminoacid receptor subunits in the brain of a genetic Parkinia modelΦραγκιουδάκη, Κλεοπάτρα 27 June 2007 (has links)
Η παρούσα διατριβή ασχολήθηκε με τη μελέτη της έκφρασης των υπομονάδων των υποδοχέων του γλουταμινικού οξέος και του γ-αμινοβουτυρικού οξέος (GABA) στα βασικά γάγγλια και τον φλοιό των εγκεφαλικών ημισφαιρίων του μυός weaver. Παράλληλα, μελετήθηκε η έκφραση των νευροπεπτιδίων εγκεφαλίνης και δυνορφίνης στα βασικά γάγγλια του μυός weaver. O μυς weaver χαρακτηρίζεται από προοδευτική, γενετικά επαγόμενη εκφύλιση των ντοπαμινεργικών κυττάρων του μεσεγκεφάλου, κυρίως αυτών οι οποίοι καταλήγουν στο ραβδωτό σώμα. Για αυτόν τον λόγο, θεωρείται ένα καλό μοντέλο της νόσου Parkinson και η μελέτη των νευροχημικών μεταβολών που συμβαίνουν στον εγκέφαλο του παραπάνω μυός, αποτελεί πολύτιμο εργαλείο για τη διερεύνηση των παθογενετικών μηχανισμών της νόσου. Mε την τεχνική του υβριδισμού in situ, προσδιορίστηκαν τα επίπεδα mRNA των υπομονάδων z1, ε1 και ε2 του υποδοχέα NMDA, των υπομονάδων KA2 και GluR6 του υποδοχέα καϊνικού οξέος, των υπομονάδων α1, α2, α4, β2 και β3 του υποδοχέα GABAA, καθώς και των πρόδρομων πολυπεπτιδίων προ-προεγκεφαλίνη και προδυνορφίνη. Η μελέτη πραγματοποιήθηκε σε φυσιολογικούς μύες (+/+) και μύες weaver (wv/wv), στις ηλικίες των 26 ημερών, 3 μηνών και 6 μηνών μετά τη γέννηση. Όσον αφορά στους υποδοχείς του γλουταμινικού οξέος, τα αποτελέσματά μας υπέδειξαν αύξηση στην έκφραση των υπομονάδων z1, ε2, ΚΑ2 και GluR6 στο ραβδωτό σώμα των μυών weaver, σε σχέση με τους φυσιολογικούς. Η αύξηση στο mRNA των υπομονάδων z1, ε2 και GluR6 παρατηρήθηκε μόνο στην ηλικία των 6 μηνών, ενώ το mRNA της υπομονάδας KA2, παρουσίασε αύξηση και στις τρεις ηλικίες που μελετήθηκαν. Οι αυξήσεις της έκφρασης των υπομονάδων z1, ε2, ΚΑ2 και GluR6 συμφωνούν και πιθανόν εξηγούν τις αυξήσεις στα επίπεδα των θέσεων δέσμευσης για τους υποδοχείς NMDA και μη-NMDA, οι οποίες έχουν βρεθεί από παλαιότερες μελέτες του εργαστηρίου μας στο ραβδωτό σώμα των μυών weaver ηλικίας 6 μηνών. Με βάση βιβλιογραφικά δεδομένα, υποστηρίζουμε ότι η καθυστερημένη αύξηση στην έκφραση των υπομονάδων z1, ε2 και GluR6 κατά πάσα πιθανότητα συντελείται μέσω επαγωγής του μεταγραφικού παράγοντα ΔfosB, σε απόκριση προς τη μείωση της ντοπαμίνης. Στον σωματοαισθητικό φλοιό των μυών weaver ηλικίας 26 ημερών, παρατηρήθηκε αύξηση στην έκφραση των υπομονάδων z1, ε1, ε2 και KA2, η οποία θα μπορούσε να οφείλεται στη μειωμένη θαλαμοφλοιϊκή γλουταμινεργική είσοδο. Όσον αφορά στους υποδοχείς GABAA, παρατηρήθηκε αύξηση στα επίπεδα mRNA των υπομονάδων α4 και β3, στο ραβδωτό σώμα των μυών weaver ηλικίας 6 μηνών, η οποία συμφωνεί και μπορεί να εξηγήσει την αύξηση στα επίπεδα των θέσεων δέσμευσης για τους υποδοχείς GABAA, η οποία έχει βρεθεί σε προηγούμενη μελέτη του εργαστηρίου μας, στο ραβδωτό σώμα των μυών weaver ηλικίας 6 μηνών. Σκοπεύουμε να ελέγξουμε την πιθανότητα, η αύξηση της έκφρασης της υπομονάδας α4, να υποδεικνύει μία αύξηση του αριθμού των εξωσυναπτικών υποδοχέων GABAA στους νευρώνες προβολής του ραβδωτού σώματος. Στην ωχρά σφαίρα των μυών weaver ηλικίας 6 μηνών, παρατηρήθηκε μείωση των επιπέδων mRNA των υπομονάδων α1 και β2, υποδεικνύοντας μία μείωση του αριθμού των υποδοχέων GABAA, η οποία ήταν αναμενόμενη, λόγω της αυξημένης GABAεργικής εισόδου στην εν λόγω εγκεφαλική περιοχή του μυός weaver. Στον σωματοαισθητικό φλοιό, παρατηρήθηκε μείωση στην έκφραση των υπομονάδων α2 και β2 και ταυτόχρονα αύξηση στην έκφραση των υπομονάδων α4 και β3. Με βάση βιβλιογραφικά δεδομένα, προτείνουμε ότι οι μεταβολές αυτές μπορεί να αντανακλούν μείωση στον αριθμό των συναπτικών και αύξηση στον αριθμό των εξωσυναπτικών υποδοχέων GABAA, σε απόκριση προς τη μειωμένη GABAεργική είσοδο προς τους νευρώνες του σωματοαισθητικού φλοιού του μυός weaver. Όσον αφορά στην έκφραση των πολυπεπτιδίων, το mRNA της προ-προεγκεφαλίνης, παρουσίασε αύξηση στο ραβδωτό σώμα των μυών weaver, μόνο στην ηλικία των 6 μηνών, ενώ το mRNA της προδυνορφίνης, παρουσίασε μείωση στην παραπάνω περιοχή, στην ηλικία των 26 ημερών και αύξηση στις μεγαλύτερες ηλικίες. Σύμφωνα με τα βιβλιογραφικά δεδομένα υποστηρίζουμε ότι: α) η καθυστερημένη αύξηση της έκφρασης της προ-προεγκεφαλίνης στο ραβδωτό σώμα του μυός weaver, οφείλεται στη μείωση της τονικής ανασταλτικής ρυθμιστικής δράσης της ντοπαμίνης στην έκφραση του εν λόγω γονιδίου και πιθανώς συντελείται μέσω του μεταγραφικού παράγοντα ΔfosB, β) ο παραπάνω μεταγραφικός παράγοντας είναι κατά πάσα πιθανότητα υπεύθυνος και για την καθυστερημένη επαγωγή της έκφρασης της προδυνορφίνης στο ραβδωτό σώμα των μυών weaver και γ) η μείωση του παραπάνω mRNA στην ηλικία των 26 ημερών οφείλεται στη μείωση της τονικής διεγερτικής δράσης της ντοπαμίνης στην έκφραση του εν λόγω γονιδίου. Τέλος, το γεγονός ότι οι μεταβολές των mRNA των διαφόρων υπομονάδων και νευροπεπτιδίων δεν ήταν οι ίδιες στις διάφορες ηλικίες που μελετήθηκαν υποδεικνύει ότι κατά την πρόοδο της ντοπαμινεργικής εκφύλισης των ντοπαμινεργικών νευρώνων του μεσεγκεφάλου διαφορετικοί μηχανισμοί ευθύνονται για την πρόκληση των αλλαγών στην έκφραση των υπό μελέτη γονιδίων. / In the present study we investigated the expression of the subunits of glutamate and γ-aminobutyric acid (GABA) receptors in basal ganglia and cerebral cortex of the weaver mouse. We also studied the expression of striatal neuropeptides, which are important neuromodulators of the synaptic transmission in the basal ganglia circuitry. The weaver mouse is characterized by a progressive, genetically induced degeneration of the mesencephalic dopaminergic neurons, especially those that project to the striatum. For this reason, the weaver mouse is a useful model for clarifying the pathogenetic mechanisms that underly Parkinson’s disease. Using the in situ hybridization method, the mRNA levels of the ΝΜDA subunits z1, ε1 and ε2, the kainate subunits KΑ2 and GluR6, the GABAA subunits α1, α2, α4, β2 and β3, as well as the mRNA levels of the precursor polypeptides pre-proenkephalin and prodynorphin, were estimated. The study was performed using wild-type (+/+) and weaver mice (wv/wv) of the following ages: 26 days, 3 months and 6 months. Concerning the glutamate receptors, an increase in the mRNA levels of z1, ε2, KA2 and GluR6 subunits was indicated in the weaver striatum, compared to the wild type. The z1, ε2 and GluR6 mRNA increases were observed only at the age of 6 months, whereas the KA2 mRNA increase was observed at all three ages studied. The increases in z1, ε2, ΚΑ2 and GluR6 mRNA expression are in agreement and probably explain the increased levels of ΝΜDA- and non-NMDA-sensitive binding sites that we had previously found in the 6 months old weaver striatum. Based on bibliographic data, we suggest that the delayed increases in z1, ε2 and GluR6 mRNA levels, are probably mediated by the delayed induction of the ΔfosB transcription factor, in response to the reduction of striatal dopamine levels. In the somatosensory cortex of 26 day old weaver mice, an increase in the levels of z1, ε1, ε2 and ΚΑ2 mRNAs was observed. The above increases can be attributed to the decreased thalamocortical glutamatergic imput. Concerning the GABAA receptors, the observed increases of the α4 and β3 mRNA levels in the 6 months old weaver striatum are in agreement and probably explain the increased levels of GABAA binding sites that we had previously found in the 6 months old weaver striatum. We are going to test the hypothesis, that the α4 mRNA increase might indicate an increase in the number of extrasynaptic GABAA receptors in striatal projection neurons. In the 6 months old weaver globus pallidus, the observed decrease in α1 and β2 mRNA levels was expected, since the GABAergic transmission is increased in the above region of the weaver brain. In the weaver somatosensory cortex, a decrease in the α2 and β2 mRNA levels and an increase in the α4 and β3 mRNA levels were observed. Based on bibliographic data, we suggest that the above alterations probably indicate a differential regulation of the synaptic versus extrasynaptic cortical GABAA receptors, in response to the decreased GABAergic presynaptic input to the weaver cortical neurons. Concerning the expression of the striatal neuropeptides, the pre-proenkephalin mRNA was increased in the weaver striatum, only at the age of 6 months. In contrast, prodynorphin mRNA was decreased in the 26 day old weaver striatum, whereas it was increased in the 3 and 6 months old weaver striatum. Based on bibliographic data, we suggest that: a) the delayed increase in the expression of pre-proenkephalin could be caused by the reduction of the tonic dopaminergic inhibitory control on the expression of the above gene in the dopamine-depleted weaver striatum and is probably mediated by the ΔfosB transcription factor; b) the above transcription factor could be responsible for the delayed induction of the prodynorphin expression in the weaver striatum as well, and c) the decrease of prodynorphin mRNA in the 26 day old weaver striatum could be attributed to the reduction of the dopaminergic stimulatory control on the expression of the above gene. Finally, the different pattern of expression alterations among the three ages studied indicates that distinct mechanisms are responsible for the observed changes, during the progress of the dopaminergic degeneration of the weaver brain.
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Les propriétés antiapoptotiques et antiautophagiques du Pituitary Adenylate Cyclase-Activating Polypeptide assurent une protection neuronale dans des modèles in vitro et in vivo de la maladie de Parkinson / Antiapoptotic and antiautophagic properties of PACAP are granting a neuronal protection in in-vitro and in-vivo models of Parkinson diseaseLamine-Ajili, Asma 16 March 2018 (has links)
La maladie de Parkinson (MP) est caractérisée par la dégénérescence des neurones dopaminergiques du mésencéphale. Elle est notamment causée par des évènements délétères tels le stress oxydatif et la neuro-inflammation, et ceux-ci mènent à la destruction des neurones par divers types de mort cellulaire. Dans ce contexte, le Pituitary Adenylate Cyclase-activating Polypeptide (PACAP), avec ses propriétés antiapoptotiques, anti-inflammatoires et antioxydantes et son aptitude à traverser la barrière hémoencéphalique (BHE), est capable d’exercer une puissante activité neuroprotectrice dans divers modèles de la MP. Par conséquent, cette molécule est prometteuse pour le développement d’une thérapie médicamenteuse. Toutefois, ses profils pharmacologiques (actions non sélectives) et pharmacocinétiques (faible stabilité métabolique) limitent son utilisation clinique. Ainsi, dans une perspective de mise au point d’une approche thérapeutique, nous avons conçu l’Ac-[Phe(pI)6, Nle17]PACAP(1-27), un analogue du PACAP possédant des profils pharmacologiques et métaboliques améliorés, et avons testé son effet sur des modèles in vitro et in vivo de la MP. In vitro (neuroblastomes humains SH-SY5Y), l’analogue stimule efficacement la production d'AMPc et réduit l’altération de l’activité mitochondriale provoquée par un agent neurotoxique (MPP+; 1-méthyl-4-phénylpyridinium). In vivo (souris traitées avec le 1-méthyl-4-phényl-1,2,3,6-tétrahydropyridine, un précurseur métabolique du MPP+), le PACAP et son dérivé synthétique restaurent l’expression de la tyrosine hydoxylase dans la substance noire et modulent la réponse inflammatoire. Bien que des baisses de la pression artérielle soient observées avec les deux peptides, l'intensité de la chute ainsi que sa durée sont significativement moins élevées avec l'analogue. Nos caractérisations biologiques ont donc montré que la mort neuronale causée par l’agent neurotoxique est considérablement atténuée par l’analogue peptidique. Elles ont également établi que cet effet est peut-être lié à une activité antiapoptotique soutenue. Dans un deuxième temps, nous avons exploré l’effet du PACAP sur le processus autophagique observé dans ces mêmes modèles de la MP. Nous avons ainsi démontré que le PACAP réduit significativement l’activité autophagique, comme évaluée par la production du complexe LC3-II, le rétablissement des niveaux protéiques de la p62, et la diminution de la formation des vacuoles autophagiques. La capacité du PACAP à inhiber l'autophagie a égalementété observée in vitro, et ce, en inhibant l'activité de p62 induite par la rapamycine, uninducteur de l'autophagie. Ainsi, nos travaux ont conduit à la description d’une molécule dérivée du PACAP, métaboliquement stable, qui s’avère aussi puissante que le peptide natif au niveau de la neuroprotection. Ils ont aussi révélé que le PACAP possède des propriétés antiautophagiques dans des modèles de la MP. / Parkinson's disease (PD) is characterized by the degeneration of mesencephalic dopaminergic neurons. In particular, it is caused by deleterious events such as oxidative stress and neuro-inflammation, which lead to the destruction of neurons by several types of cell death. In this context, the Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP), with its antiapoptotic, anti-inflammatory and antioxidant properties, as well as its ability to cross the blood-brain barrier (BBB), is able to exert a potent neuroprotective activity in various PD models. Therefore, this molecule is promising for the development of a PACAP-based drug therapy. However, its pharmacological (non-selective) and pharmacokinetic (low metabolic stability) profiles limit its clinical use. Thus, from the perspective of developing a therapeutic approach, we designed the analog Ac-[Phe(pI)6, Nle17]PACAP(1-27), a PACAP derivative with improved pharmacological and metabolic profiles, and tested its effects in in vitro and in vivo PD models. In vitro (SH-SY5Y human neuroblastoma cells), the analog effectively stimulates the production of cAMP and reduces the alteration of mitochondrial activity caused by a neurotoxic agent (MPP+; 1- methyl-4-phenylpyridinium). In vivo (mice treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, a metabolic precursor of MPP+), PACAP and its synthetic derivative restore tyrosine hydroxylase expression in the substantia nigra and modulate the inflammatory response. Although decreases in blood pressure were observed with both peptides, the intensity of the fall and its duration were significantly lower with the analog. Our biological characterizations have thus shown that the neuronal death caused by the neurotoxic agent is considerably attenuated by the peptide analog. They also established that this effect may be related to sustained antiapoptotic activity. In a second step, we explored the effect of PACAP on the autophagic process observed in these same PD models. Thus, we have demonstrated that PACAP significantly reduces autophagic activity, as assessed by the production of the LC3-II complex, the restoration of the p62 protein levels, and the decreased formation of autophagic vacuoles. The ability of PACAP to impede autophagy was also observed in vitro, by the inhibition of the p62 activity produced by rapamycin, an inducer of autophagy. In summary, our work led to the description of a PACAP-derived molecule, metabolically stable, that proved to be in neuroprotection as potent as the native peptide. Our studies also revealed that PACAP possesses antiautophagic properties in PD models.
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Innovative MRT-Kontraste zur in-vivo-Differenzierung von Patienten mit typischem idiopathischen Parkinson und atypischen Parkinsonsyndromen / Innovative MRI contrasts for in-vivo-differentiation of patients with typical idiopathic Parkinson's syndromes and atypical parkinsonian syndromesPantel, Pia Marie 13 January 2014 (has links)
HINTERGRUND/ ZIELSETZUNG:
Vom idiopathischen Parkinsonsyndrom (IPS) können so genannte „atypische“ Parkinsonsyndrome (APS) mit einem Anteil von ca. 20% bezogen auf die Gesamtinzidenz unterschieden werden. Neben zusätzlichen Krankheitssymptomen und einem progredienteren Verlauf zeichnen sie sich durch eine schlechtere Prognose aus, die häufig auf einem Nichtansprechen auf eine dopaminerge Therapie beruht. Eine frühzeitige, korrekte Diagnose ist daher sehr entscheidend, aber im Einzelfall auch für Spezialisten äußerst schwierig. Trotz anerkannter klinischer Diagnosekriterien gibt es besonders im Frühstadium eine hohe Rate an Fehldiagnosen.
Das zur Zeit vorherrschende Verfahren in der bildgebenden Diagnostik ist die Magnetresonanztomographie, wobei die konventionelle, qualitative MRT bislang keine zufriedenstellenden Ergebnisse bezüglich ihrer Spezifität und Sensitivität gezeigt hat.
Die vorliegende Arbeit untersucht in einer direkten Vergleichsstudie das differenzialdiagnostische Potential der sogenannten „erweiterten“ quantitativen MRT-Verfahren.
MATERIAL UND METHODEN:
Ein Gesamtkollektiv von insgesamt 44 Probanden (IPS/ APS/ gesunde Kontrollen) durchlief ein umfassendes quantitatives MRT- Protokoll (R1/R2(*)-, DTI-, MTR- Mapping) um in manuell bilateral markierten, definierten Regionen (ROIs) in den Basalganglienkernen quantitative Parameter zu erheben.
ERGEBNISSE:
Die beste hochsignifikante Trennung der MSA-P- Patienten sowohl von IPS- Patienten (p = 0,001) als auch von Kontrollen (p = 0,004) konnte anhand des R2 * - Mappings im Putamen erreicht werden. Es zeigte sich eine Vorhersagekraft AUC von > / = 0,96 mit einer Sensitivität von 77,8 % (bei einer Spezifität von 100 %). Dies bestätigt die große Bedeutung der Eisensensitivität des R2*-Mappings bei der Identifizierung von MSA-P- Patienten.
Auch anhand des MTR-Mappings konnte eine MSA-P anhand der putaminalen (p = 0,005) und nigralen (p = 0,003) Signalveränderungen signifikant vorhergesagt werden.
Die beste signifikante Abgrenzung der PSP- Patienten von den Kontrollen gelang anhand der DTI- Messungen in der Substantia nigra (p = 0,001) sowie im Globus pallidus (p = 0,004).
Für die diagnostische Vorhersage eines IPS konnten keine nutzbaren Signalunterschiede festgestellt werden. Insbesondere in der Substantia nigra zeigten sich gegenüber Kontrollen keine signifikanten Gruppenunterschiede.
FAZIT:
Unter den angewandten MRT- Verfahren zeigt das R2*-Mapping die beste Vorhersagekraft zur Differenzierung der MSA von IPS- Patienten und das DTI- Mapping zur Identifizierung der PSP- Patienten. Das Besondere unseres Arbeitsansatzes war, im Gegensatz zu vorherigen Studien, die Durchführung der Untersuchung an nur einer Kohorte. Dadurch konnte die Güte der verschiedenen MRT-Verfahren direkt und quantitativ miteinander verglichen werden.
Insgesamt unterstreichen die Erkenntnisse dieser Arbeit den Stellenwert und die mögliche klinische Relevanz der quantitativen MRT, insbesondere bei der Identifizierung atypischer Parkinsonsyndrome.
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