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1.
Pract Neurol ; 24(1): 41-44, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-37802651

RESUMO

A young man from Pakistan had his first-ever tonic-clonic seizure while playing cricket. Since age 12 years, he had reported involuntary jerks and tremulousness, sometimes with falls, particularly with bright lights. Family history included a brother who developed seizures with myoclonus in his mid-20s and parental consanguinity. Developmental history was normal. Examination identified cognitive impairment with action myoclonus. His clinical presentation raised suspicion of a progressive myoclonus epilepsy. MR scan of the brain showed white matter changes suggesting leucodystrophy with cortical atrophy. Electroencephalogram showed generalised epileptiform abnormalities with photoparoxysmal responses, including at low frequencies (1 Hz). Cortical hyperexcitability was confirmed with giant median somatosensory evoked potentials and long loop reflexes at rest. Multichannel electromyography showed action myoclonus with variable synchronous and asynchronous agonist and antagonist muscle activation with short-burst duration of 25-75 ms, and jerk-locked back-averaging showed premyoclonic potentials consistent with cortical myoclonus. Genetic sequencing identified a homozygous missense variant in the CLN6 gene (c.768C>G p.(Asp256Glu), confirming Kufs disease type A.


Assuntos
Epilepsias Mioclônicas Progressivas , Mioclonia , Lipofuscinoses Ceroides Neuronais , Masculino , Adulto , Humanos , Criança , Encéfalo , Eletroencefalografia , Convulsões , Eletromiografia , Proteínas de Membrana
2.
Neurosci Biobehav Rev ; 149: 105166, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37054804

RESUMO

Depression and apathy are associated with decreased functional capacity in Huntington's disease (HD) but frequency of depression and apathy in HD is largely unknown. Systematic literature searching was conducted across 21 databases until 30 June 2021. Inclusion criteria was limited to clinician-rated assessments of depression and apathy and adult-onset HD. Inverse-variance heterogeneity meta-analyses were conducted exploring depression and apathy frequency within individuals from families affected by HD, and within individuals with confirmed HD gene-positive status. Screening identified 289 articles for full-text review; nine remained for meta-analysis. Depression frequency in the lifetime in adults affected by or at-risk for HD was 38%, I2 = 99%. Apathy frequency in the lifetime in adults affected by or at-risk for HD was 40%, I2 = 96%. The robustness of the findings improved when limiting the analysis to gene-positive individuals only where apathy was found to be slightly more common than depression, 48% and 43% respectively. Future studies may consider reporting results from juvenile-onset HD and adult-onset HD cohorts separately to further explore phenotypic profiles.


Assuntos
Apatia , Doença de Huntington , Adulto , Humanos , Doença de Huntington/complicações , Doença de Huntington/epidemiologia , Depressão/epidemiologia
3.
BMJ Open ; 12(4): e054725, 2022 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-35437246

RESUMO

INTRODUCTION: Exercise and physical activity have been shown to improve cognition for people living with mild cognitive impairment (MCI). There is strong evidence for the benefits of aerobic exercise and medium evidence for participating in regular strength training for people with MCI. However, people living with MCI fall two times as often as those without cognitive impairment and the evidence is currently unknown as to whether balance training for people with MCI is beneficial, as has been demonstrated for older people without cognitive impairment. The aim of this study is to determine whether a balance-focused multimodal exercise intervention improves balance and reduces falls for people with MCI, compared with a control group receiving usual care. METHODS AND ANALYSIS: This single blind randomised controlled trial (Balance on the Brain) will be offered to 396 people with MCI living in the community. The multimodal exercise intervention consists of two balance programmes and a walking programme to be delivered by physiotherapists over a 6-month intervention period. All participants will be followed up over 12 months (for the intervention group, this involves 6-month intervention and 6-month maintenance). The primary outcomes are (1) balance performance and (2) rate of falls. Physical performance, levels of physical activity and sedentary behaviour, quality of life and cognition are secondary outcomes. A health economic analysis will be undertaken to evaluate the cost-effectiveness of the intervention compared with usual care. ETHICS AND DISSEMINATION: Ethics approval has been received from the South Metropolitan Health Service Human Research Ethics Committee (HREC), Curtin University HREC and the Western Australia Department of Health HREC; and approval has been received to obtain data for health costings from Services Australia. The results will be disseminated through peer-review publications, conference presentations and online platforms. TRIAL REGISTRATION NUMBER: ACTRN12620001037998; Australian New Zealand Clinical Trials Registry (ANZCTR).


Assuntos
Disfunção Cognitiva , Qualidade de Vida , Idoso , Austrália , Encéfalo , Cognição , Disfunção Cognitiva/terapia , Exercício Físico , Terapia por Exercício/métodos , Humanos , Desempenho Físico Funcional , Ensaios Clínicos Controlados Aleatórios como Assunto , Método Simples-Cego
4.
BMJ Open ; 12(2): e058826, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35190446

RESUMO

INTRODUCTION: Preclinical, clinical and epidemiological studies support the hypothesis that aberrant systemic metabolism of amyloid beta (Aß) in the peripheral circulation is causally related to the development of Alzheimer's disease (AD). Specifically, recent studies suggest that increased plasma concentrations of lipoprotein-Aß compromise the brain microvasculature, resulting in extravasation and retention of the lipoprotein-Aß moiety. The latter results in an inflammatory response and neurodegeneration ensues. Probucol, a historic cholesterol-lowering drug, has been shown in murine models to suppress lipoprotein-Aß secretion, concomitant with maintaining blood-brain-barrier function, suppressing neurovascular inflammation and supporting cognitive function. This protocol details the probucol in Alzheimer's study, a drug intervention trial investigating if probucol has potential to attenuate cognitive decline, delay brain atrophy and reduce cerebral amyloid burden in patients with mild-to-moderate AD. METHODS AND ANALYSIS: The study is a phase II, randomised, placebo-controlled, double-blind single-site clinical trial held in Perth, Australia. The target sample is 314 participants with mild-to-moderate AD. Participants will be recruited and randomised (1:1) to a 104-week intervention consisting of placebo induction for 2 weeks followed by 102 weeks of probucol (Lorelco) or placebo. The primary outcome is changed in cognitive performance determined via the Alzheimer's Disease Assessment Scales-Cognitive Subscale test between baseline and 104 weeks. Secondary outcomes measures will be the change in brain structure and function, cerebral amyloid load, quality of life, and the safety and tolerability of Lorelco, after a 104week intervention. ETHICS AND DISSEMINATION: The study has been approved by the Bellberry Limited Human Research Ethics Committee (approval number: HREC2019-11-1063; Version 4, 6 October 2021). Informed consent will be obtained from participants prior to any study procedures being performed. The investigator group will disseminate study findings through peer-reviewed publications, key conferences and local stakeholder events. TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trials Registry (ACTRN12621000726853).


Assuntos
Doença de Alzheimer , Probucol , Peptídeos beta-Amiloides/metabolismo , Animais , Austrália , Ensaios Clínicos Fase II como Assunto , Cognição , Método Duplo-Cego , Humanos , Camundongos , Probucol/farmacologia , Probucol/uso terapêutico , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
5.
BMJ Case Rep ; 12(4)2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30975772

RESUMO

A 47-year-old woman presented with six episodes of horizontal binocular double vision over a 2-year period. CT imaging was significant for extensive dural calcification in the spine and calcification of the skull base, likely involving Dorello's canal. Biochemical testing revealed a persistently low alkaline phosphatase level. Recurrent nerve palsy may possibly be induced by mechanical compression of the sixth cranial nerve in Dorello's canal from calcification due to hypophosphatasia syndrome.


Assuntos
Doenças do Nervo Abducente/diagnóstico por imagem , Hipofosfatasia/diagnóstico por imagem , Síndromes de Compressão Nervosa/diagnóstico por imagem , Ossificação Heterotópica/diagnóstico por imagem , Base do Crânio/inervação , Doenças do Nervo Abducente/complicações , Diagnóstico Diferencial , Diplopia/etiologia , Feminino , Humanos , Hipofosfatasia/sangue , Hipofosfatasia/complicações , Pessoa de Meia-Idade , Síndromes de Compressão Nervosa/complicações , Ossificação Heterotópica/complicações , Tomografia Computadorizada por Raios X
7.
Alzheimers Res Ther ; 9(1): 13, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28253913

RESUMO

BACKGROUND: Retinal imaging may serve as an alternative approach to monitor brain pathology in Alzheimer's disease (AD). In this study, we investigated the association between retinal vascular and structural changes and cerebral amyloid-ß (Aß) plaque load in an elderly cohort. METHODS: We studied a total of 101 participants, including 73 elderly subjects (79 ± 5 years, 22 male) with no clinical diagnosis of AD but reporting some subjective memory change and an additional 28 subjects (70 ± 9 years, 16 male) with clinically established AD. Following a complete dilated ocular examination, the amplitude of retinal vascular pulsations and dynamic response, retinal nerve fibre layer thickness and retinal ganglion cell layer (RGCL) thickness were determined in all patients. Systemic blood pressure and carotid-to-femoral pulse wave velocity were measured. The elderly cohort also underwent magnetic resonance imaging and 18F-florbetaben (FBB)-positron emission tomographic amyloid imaging to measure neocortical Aß standardised uptake value ratio (SUVR), and this was used to characterise a 'preclinical' group (SUVR >1.4). RESULTS: The mean FBB neocortical SUVR was 1.35 ± 0.3. The amplitude of retinal venous pulsations correlated negatively with the neocortical Aß scores (p < 0.001), whereas the amplitude of retinal arterial pulsations correlated positively with neocortical Aß scores (p < 0.01). RGCL thickness was significantly lower in the clinical AD group (p < 0.05). CONCLUSIONS: The correlation between retinal vascular changes and Aß plaque load supports the possibility of a vascular component to AD. Dynamic retinal vascular parameters may provide an additional inexpensive tool to aid in the preclinical assessment of AD.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Placa Amiloide/diagnóstico por imagem , Retina/diagnóstico por imagem , Vasos Retinianos/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/fisiopatologia , Disfunção Cognitiva/diagnóstico por imagem , Estudos de Coortes , Feminino , Hemodinâmica , Humanos , Masculino , Tamanho do Órgão , Placa Amiloide/fisiopatologia , Retina/fisiopatologia , Vasos Retinianos/diagnóstico por imagem
8.
Genome Announc ; 3(3)2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25953189

RESUMO

Papillomaviruses are epitheliotropic, circular, double-stranded DNA viruses within the family Papillomaviridae that are associated with benign and malignant tumors in humans and animals. We report the complete genome sequence of canine papillomavirus type 16 identified within multiple pigmented cutaneous plaques and squamous cell carcinoma from an intact female Basenji dog.

9.
J Clin Neurosci ; 21(7): 1169-75, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24518268

RESUMO

We report a series of patients with a clinical syndrome characterised by the explosive onset in adulthood of recurrent focal seizures of frontotemporal onset and features suggestive of autoimmune encephalitis. We propose that this presentation of "autoimmune adult onset focal epilepsy and encephalitis" is a recognisable clinical syndrome, and provide evidence it may be associated with heterogeneous immunological targets. Between 2008 and 2011 we encountered six patients with new-onset epilepsy in whom we suspected an autoimmune aetiology. We first characterised the clinical, electroencephalographic, cerebrospinal fluid (CSF), imaging, and pathological findings of this syndrome. We subsequently tested them for antibodies against both intracellular and neuronal cell surface antigens. All patients presented with recurrent seizures with focal frontotemporal onset, refractory to multiple anticonvulsants. Four had focal T2-weighted hyperintensities on MRI. CSF mononuclear cells were variably elevated with positive oligoclonal bands in four. Brain biopsy in one patient demonstrated perivascular lymphocytic infiltration. Two were treated with immunosuppression and went on to achieve complete seizure control and return to baseline cognition. Three of four patients who received only pulsed steroids or no treatment had ongoing frequent seizures, with two dying of sudden unexpected death in epilepsy. Subsequently, three had antibodies identified against neuronal cell surface antigens including N-methyl-D-aspartate receptor and leucine-rich glioma inactivated 1. We suggest that patients with such a presentation should be carefully evaluated for a suspected autoimmune aetiology targeting cell surface antigens and have a therapeutic trial of immunosuppression as this may improve their long-term outcome.


Assuntos
Encefalopatias/complicações , Epilepsias Parciais/complicações , Doença de Hashimoto/complicações , Adulto , Encefalopatias/líquido cefalorraquidiano , Encefalopatias/diagnóstico , Encefalopatias/terapia , Eletroencefalografia , Encefalite , Epilepsias Parciais/líquido cefalorraquidiano , Epilepsias Parciais/diagnóstico , Epilepsias Parciais/terapia , Feminino , Doença de Hashimoto/líquido cefalorraquidiano , Doença de Hashimoto/diagnóstico , Doença de Hashimoto/terapia , Humanos , Imunomodulação , Peptídeos e Proteínas de Sinalização Intracelular , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Bandas Oligoclonais/metabolismo , Tomografia por Emissão de Pósitrons , Proteínas/imunologia , Receptores de N-Metil-D-Aspartato/imunologia , Estudos Retrospectivos , Adulto Jovem
10.
Neurology ; 81(9): 833-40, 2013 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23892702

RESUMO

OBJECTIVE: To determine the risk factors associated with dementia with Lewy bodies (DLB). METHODS: We identified 147 subjects with DLB and sampled 2 sex- and age-matched cognitively normal control subjects for each case. We also identified an unmatched comparison group of 236 subjects with Alzheimer disease (AD). We evaluated 19 candidate risk factors in the study cohort. RESULTS: Compared with controls, subjects with DLB were more likely to have a history of anxiety (odds ratio; 95% confidence interval) (7.4; 3.5-16; p < 0.0001), depression (6.0; 3.7-9.5; p < 0.0001), stroke (2.8; 1.3-6.3; p = 0.01), a family history of Parkinson disease (PD) (4.6; 2.5-8.6; p < 0.0001), and carry APOE ε4 alleles (2.2; 1.5-3.3; p < 0.0001), but less likely to have had cancer (0.44; 0.27-0.70; p = 0.0006) or use caffeine (0.29; 0.14-0.57; p < 0.0001) with a similar trend for alcohol (0.65; 0.42-1.0; p = 0.0501). Compared with subjects with AD, subjects with DLB were younger (72.5 vs 74.9 years, p = 0.021) and more likely to be male (odds ratio; 95% confidence interval) (5.3; 3.3-8.5; p < 0.0001), have a history of depression (4.3; 2.4-7.5; p < 0.0001), be more educated (2.5; 1.1-5.6; p = 0.031), have a positive family history of PD (5.0; 2.4-10; p < 0.0001), have no APOE ε4 alleles (0.61; 0.40-0.93; p = 0.02), and to have had an oophorectomy before age 45 years (7.6; 1.5-39; p = 0.015). CONCLUSION: DLB risk factors are an amalgam of those for AD and PD. Smoking and education, which have opposing risk effects on AD and PD, are not risk factors for DLB; however, depression and low caffeine intake, both risk factors for AD and PD, increase risk of DLB more strongly than in either.


Assuntos
Doença de Alzheimer/complicações , Demência/etiologia , Corpos de Lewy , Doença por Corpos de Lewy/complicações , Doença de Parkinson/complicações , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Estudos de Casos e Controles , Feminino , Humanos , Doença por Corpos de Lewy/diagnóstico , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco
12.
J Neuroimmunol ; 252(1-2): 95-9, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22910543

RESUMO

Gene association with HLA suggests involvement of immune mediated mechanisms in the pathogenesis of Parkinson's disease (PD). Only a small number of studies have found differences between circulating leukocyte populations in PD patients compared to controls, with conflicting results. To clarify whether there is a circulating leukocyte PD phenotype, we assessed the numbers of T, B and natural killer cells, and monocytes and found a small reduction (15-25%) in CD4+ T and CD19+ B cells in PD. These findings suggest some compromise in immune cells in PD and have potential implications for immune function and the progression of PD.


Assuntos
Linfócitos B/imunologia , Doença de Parkinson/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Idoso , Feminino , Citometria de Fluxo , Humanos , Masculino , Doença de Parkinson/sangue
13.
Arch Neurol ; 68(9): 1165-70, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21911696

RESUMO

OBJECTIVE: To report the clinical, electroencephalographic, and neuroradiologic findings in a kindred with a novel insertion in the prion protein gene, PRNP. DESIGN: Clinical description of a kindred. SETTING: Mayo Clinic Alzheimer Disease Research Center (Rochester, Minnesota). SUBJECTS: Two pathologically confirmed cases and their relatives. MAIN OUTCOME MEASURES: Clinical features, electroencephalographic patterns, magnetic resonance imaging abnormalities, genetic analyses, and neuropathologic features. RESULTS: The proband was a woman with clinical and neuroimaging features of atypical frontotemporal dementia and ataxia. Generalized tonic-clonic seizures developed later in the disease course, and electroencephalography revealed spike and wave discharges but no periodic sharp-wave complexes. Her affected sister and father also exhibited frontotemporal dementia-like features, and both experienced generalized tonic-clonic seizures and gait ataxia late in the disease course. Genetic analyses in the proband identified a novel defect in PRNP, with 1 mutated allele carrying a 288-base pair insertion consisting of 12 octapeptide repeats. Neuropathologic examination of the proband and her sister revealed prion protein-positive plaques and widespread tau-positive tangles. CONCLUSIONS: This kindred has a unique combination of clinical and neuropathologic features associated with the largest base pair insertion identified to date in PRNP and underscores the need to consider familial prion disease in the differential diagnosis of a familial frontotemporal dementia-like syndrome.


Assuntos
Oligopeptídeos/genética , Doenças Priônicas/genética , Príons/genética , Sequências Repetitivas de Aminoácidos/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Doenças Priônicas/diagnóstico , Proteínas Priônicas
14.
Psychiatry (Edgmont) ; 7(5): 27-32, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20532155

RESUMO

OBJECTIVE: To investigate the safety of rechallenge with lamotrigine after an initial rash in patients with refractory bipolar depression. DESIGN: 1) Prospective, open-label case series in a private practice setting. Patients who developed an initial rash on lamotrigine and were refractory to other treatments were offered rechallenge with the drug using very-low-dose titration (5mg every other day or daily for 14 days, then raised every 14 days by daily-dose increments of 5mg; after 25mg/day the titration proceeded according to the manufacturer's guidelines); and 2) A meta-analysis of prior reports of rechallenge with lamotrigine was conducted. MEASURES: A rating scale for rash severity was developed for this study. RESULTS: Of 27 patients rechallenged with lamotrigine, five required discontinuation due to rash or inflammation. Two of these were potentially serious and all resolved with discontinuation of lamotrigine. Review of the literature identified 48 cases of lamotrigine rechallenge with a success rate of 87 percent; in pooled analysis with the current study the success rate was 85 percent. No patients developed Stevens-Johnson syndrome or toxic epidermal necrolysis after rechallenge. The rate of rash was elevated when rechallenge began within four weeks of the initial rash (36% vs. 7%, p=0.002) and reduced when the initial rash had no signs of potential seriousness (0% vs. 23%, p=0.01). CONCLUSIONS: Rechallenge is a viable option after a benign rash on lamotrigine and can be undertaken with more caution after rashes with 1 to 2 signs of potential seriousness. For rashes with three or more signs of seriousness, rechallenge is not well-studied and may carry significant risk. Rechallenge should be avoided within four weeks of the initial rash.

15.
Arch Neurol ; 66(7): 865-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19597088

RESUMO

OBJECTIVE: To assess the incidence, severity, and spectrum of neurologic toxic effects associated with administration of amiodarone hydrochloride. DESIGN: Retrospective medical record analysis of cardiac patients treated with amiodarone between January 1, 1996, and July 31, 2008. SETTING: Residents of Olmsted County, Minnesota, treated at the Mayo Clinic. PATIENTS: The Mayo Clinic medical records of all adult Olmsted County residents prescribed amiodarone between January 1, 1996, and July 31, 2008, were reviewed and all possible neurologic adverse effects that might be attributable to amiodarone were tabulated. MAIN OUTCOME MEASURES: Risk factors and clinical characteristics of patients developing neurologic problems were compared with those who did not. RESULTS: Over the 151 months of analysis, 707 patients were treated with amiodarone. Among these patients, the cumulative incidence of likely amiodarone neurotoxic effects was 2.8%; 1.6% of all amiodarone-treated patients were referred to Neurology for a neurotoxic reaction. Neurologic problems included tremor, gait ataxia, peripheral neuropathy, and cognitive impairment. The primary risk factor for amiodarone neurotoxic effects was duration of treatment, not age, drug dose, sex, or indication for therapy. Where this could be assessed, the adverse effects were usually but not always reversible. CONCLUSIONS: Amiodarone infrequently causes clinically significant neurologic toxic effects. Substantially higher estimates of neurotoxic effects in the early amiodarone era may be related to a much higher daily dose.


Assuntos
Amiodarona/efeitos adversos , Antiarrítmicos/efeitos adversos , Síndromes Neurotóxicas/etiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Cardiopatias/tratamento farmacológico , Humanos , Masculino , Registros Médicos/estatística & dados numéricos , Exame Neurológico/métodos , Estudos Retrospectivos , Fatores de Risco
16.
Parkinsonism Relat Disord ; 15 Suppl 3: S1-5, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20082965

RESUMO

Non-motor manifestations of Parkinson disease (PD) are common and some may actually antedate motor dysfunction. Extrapyramidal signs in PD are tightly linked to striatonigral dopaminergic denervation associated with neuronal loss and Lewy bodies in the residual neurons of the substantia nigra. Lewy bodies composed of abnormal alpha-synuclein are the histologic hallmark of PD, and their presence beyond midbrain dopaminergic neurons is considered to be the pathologic substrate of many, if not all, of the non-motor manifestations of PD. We review the pathologic correlates of autonomic dysfunction (cardiac and gastrointestinal), hyposmia, depression, rapid eye movement behavior disorder and dementia in PD For each non-motor clinical feature there is strong evidence to suggest a role for alpha-synuclein pathology, lending further support for the notion that PD is a multisystem alpha-synucleinopathy.


Assuntos
Corpos de Lewy/patologia , Doença de Parkinson/complicações , Doença de Parkinson/patologia , alfa-Sinucleína/metabolismo , Animais , Ansiedade/etiologia , Ansiedade/metabolismo , Ansiedade/patologia , Doenças do Sistema Nervoso Autônomo/etiologia , Doenças do Sistema Nervoso Autônomo/metabolismo , Doenças do Sistema Nervoso Autônomo/patologia , Demência/etiologia , Demência/metabolismo , Demência/patologia , Depressão/etiologia , Depressão/metabolismo , Depressão/patologia , Humanos , Transtorno do Comportamento do Sono REM/etiologia , Transtorno do Comportamento do Sono REM/metabolismo , Transtorno do Comportamento do Sono REM/patologia
17.
Brain ; 128(Pt 11): 2665-74, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16219675

RESUMO

The pathogenesis of idiopathic Parkinson's disease is unknown, but nigral degeneration and depigmentation are associated with microglial inflammation and anti-inflammatory medications appear to protect against the disease. The possibility that humoral immunity may play a role in initiating or regulating the inflammation has been suggested by experimental studies triggering dopamine cell death using a variety of transfer strategies and the observation of CD8+ T lymphocytes and complement in the nigra in Parkinson's disease. We analysed the association between degeneration and humoral immune markers in brain tissue of patients with idiopathic (n = 13) or genetic (n = 2 with alpha-synuclein and n = 1 with parkin mutations) Parkinson's disease and controls without neurological disease (n = 12) to determine the humoral immune involvement in Parkinson's disease. Formalin-fixed tissue samples from the substantia nigra and primary visual cortex for comparison were stained for alpha-synuclein, major histocompatibility complex II (HLA), immunoglobulin M (IgM), immunoglobulin G (IgG), IgG subclasses 1-4 and IgG receptors FcgammaR I-III. Antigen retrieval and both single immunoperoxidase and double immunofluorescence procedures were employed to determine the cell types involved and their pattern and semiquantitative densities. Significant dopamine neuron loss occurred in all patients with Parkinson's disease, negatively correlating with disease duration (r = -0.76, P = 0.002). Although all patients had increased inflammatory HLA immunopositive microglia, the degree of inflammation was similar throughout the disease (r = 0.08, P = 0.82). All patients with Parkinson's disease had IgG binding on dopamine neurons but not IgM binding. Lewy bodies were strongly immunolabelled with IgG. A mean 30 +/- 12% of dopamine nigral neurons were immunoreactive for IgG in Parkinson's disease with the proportion of IgG immunopositive neurons negatively correlating with the degree of cell loss in the substantia nigra (r = -0.67, P < 0.0001) and positively correlating with the number of HLA immunopositive microglia (r = 0.51, P = 0.01). Most neuronal IgG was the IgG1 subclass with some IgG3 and less IgG2 also found in the damaged substantia nigra. The high affinity activating IgG receptor, FcgammaRI, was expressed on nearby activated microglia. The low affinity activating IgG receptor, FcgammaRIII was expressed on cells morphologically resembling lymphocytes, whereas immunoreactivity for the inhibitory IgG receptor FcgammaRII was absent in all cases. This pattern of humoral immune reactivity is consistent with an immune activation of microglia leading to the targeting of dopamine nigral neurons for destruction in both idiopathic and genetic cases of Parkinson's disease.


Assuntos
Doença de Parkinson/imunologia , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Antígenos de Histocompatibilidade Classe I/análise , Humanos , Imunoglobulina G/metabolismo , Imunoglobulina M/metabolismo , Corpos de Lewy/imunologia , Masculino , Microglia/imunologia , Pessoa de Meia-Idade , Mutação , Neurônios/imunologia , Neurônios/patologia , Doença de Parkinson/genética , Doença de Parkinson/patologia , Receptores de IgG/metabolismo , Substância Negra/imunologia , Ubiquitina-Proteína Ligases/genética , Córtex Visual/imunologia , alfa-Sinucleína/genética
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