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BACKGROUND: Spinocerebellar ataxia 2 (SCA2) with a low range of CAG repeat expansion of ATXN2 gene can present with predominant or isolated parkinsonism that closely resembles Parkinson's disease (PD). This study is aimed at comparing clinical features, disease progression, and nuclear imaging between ATXN2-related parkinsonism (ATXN2-P) and PD. METHODS: Three hundred and seventy-seven clinically diagnosed PD with family history were screened by multiplex ligation-dependent probe amplification, whole-exome sequencing or target sequencing, and dynamic mutation testing of 10 SCA subtypes. The baseline and longitudinal clinical features as well as the dual-tracer positron emission tomography (PET) imaging were compared between ATXN2-P and genetically undefined familial PD (GU-fPD). RESULTS: Fifteen ATXN2-P patients from 7 families and 50 randomly selected GU-fPD patients were evaluated. Significantly less resting tremor and more symmetric signs were observed in ATXN2-P than GU-fPD. No significant difference was found in motor progression and duration from onset to occurrence of fluctuation, dyskinesia, and recurrent falls between the two groups. Cognitive impairment and rapid-eye-movement sleep behavior disorder were more common in ATXN2-P. During follow-up, olfaction was relatively spared, and no obvious progression of cognition dysfunction evaluated by Mini-Mental State Examination scores was found in ATXN2-P. PET results of ATXN2-P demonstrated a symmetric, diffuse, and homogenous dopamine transporter loss of bilateral striatum and a glucose metabolism pattern inconsistent with that in PD. CONCLUSIONS: Symmetric motor signs and unique nuclear imaging might be the clues to distinguish ATXN2-P from GU-fPD.
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Ataxina-2 , Progressão da Doença , Transtornos Parkinsonianos , Tomografia por Emissão de Pósitrons , Humanos , Masculino , Feminino , Ataxina-2/genética , Pessoa de Meia-Idade , Estudos Longitudinais , Transtornos Parkinsonianos/genética , Transtornos Parkinsonianos/diagnóstico por imagem , Adulto , Idoso , Ataxias Espinocerebelares/diagnóstico por imagem , Ataxias Espinocerebelares/genética , Estudos de CoortesRESUMO
BACKGROUND: There was a paucity of follow-up studies in the disease progression of early-onset PD patients with Parkin mutations (Parkin-EOPD). Here we conducted a longitudinal study to investigate the progression of motor and cognitive features of Parkin-EOPD patients. METHODS: Genetic analysis was performed via target sequencing and multiplex ligation-dependent probe amplification. Thirty patients carrying homozygous or compound heterozygous Parkin mutations with at least 2 follow-up revisions were investigated as the Parkin-EOPD group. Fifty-two patients with at least 2 follow-up revisions, who did not have any known causative PD mutations, GBA or LRRK2 risk variants, a heterozygous Parkin mutation or 2 Parkin mutations without a segregation test, were defined as the genetically undefined EOPD (GU-EOPD) group. A linear mixed-effect model was implemented to evaluate longitudinal changes in motor symptoms and cognition. RESULTS: At baseline, the Parkin-EOPD group had a lower Unified Parkinson's Disease Rating Scale score (UPDRS-III) (off-medication) than the GU-EOPD group, without significant differences in cognition. A longitudinal study showed the estimated progression rate per year (standard error) of the UPDRS-III score (off-medication) was lower in the Parkin-EOPD group (0.203 [0.3162] points per year) than in the GU-EOPD group (1.056 [0.3001] points per year). The difference in the UPDRS-III score rate between the 2 groups was 0.853 (0.4183) (P = 0.042). The Parkin-EOPD group showed better maintenance of spatial processing ability compared with the GU-EOPD group (P = 0.027). CONCLUSION: Parkin-EOPD patients showed a slower deterioration of motor symptoms and a better spatial processing ability than GU-EOPD patients, which suggests that subtyping according to genetic features can help predict PD progression. © 2020 International Parkinson and Movement Disorder Society.
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Doença de Parkinson , Idade de Início , Progressão da Doença , Heterozigoto , Humanos , Estudos Longitudinais , Mutação/genética , Doença de Parkinson/genética , Ubiquitina-Proteína Ligases/genéticaRESUMO
Cerebrotendinous xanthomatosis (CTX) is a lipid-storage disease caused by mutations in CYP27A1. Current publications of Chinese CTX were mainly based on case reports. Here we investigated the clinical manifestations, genetic features in Chinese CTX patients. The clinical materials of 4 Chinese CTX pedigrees were collected. The genetic testing was done by polymerase chain reaction plus Sanger sequencing. The features of Chinese CTX patients reported previously were also reviewed. Three novel mutations of p.Arg513Cys, c.1477-2A > C in family 1 and p.Arg188Stop in family 4 (NM 000784.3) in CYP27A1 were found. The probands in our study manifested cerebellar ataxia, tendon xanthoma and spastic paresis in family 1 and 4, tendon xanthoma plus spastic paraparesis in family 2, asymptomatic tendon xanthoma in family 3. Three known mutations of p.Arg137Gln, p.Arg127Trp and p.Arg405Gln were found respectively in Family 2, 3 and 4. For the Chinese patients reviewed, the most common findings were xanthomatosis (100%), pyramidal signs (100%), cerebellar ataxia (66.7%), cognitive impairment (66.7%), cataracts (50.0%), and peripheral neuropathy (33.3%). Chronic diarrhea was infrequently seen (5.6%). No mutation was found associated with any given clinical features. We identified 3 novel mutations in CYP27A1. In Chinese CTX patients, xanthomatosis was the most common symptom while cataracts and chronic diarrhea were less frequent. The special features in Chinese CTX patients might caused by the lack of serum cholestanol test and should be confirmed in larger number of patients in the future.
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Colestanotriol 26-Mono-Oxigenase/genética , Xantomatose Cerebrotendinosa/genética , Xantomatose Cerebrotendinosa/fisiopatologia , Adulto , Idade de Início , Povo Asiático , Ataxia Cerebelar/genética , Ataxia Cerebelar/fisiopatologia , Colestanol , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/genética , Progressão da Doença , Feminino , Testes Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Paraparesia Espástica/genética , Paraparesia Espástica/fisiopatologia , Linhagem , Reação em Cadeia da Polimerase , Xantomatose/genética , Xantomatose/fisiopatologia , Xantomatose Cerebrotendinosa/psicologiaAssuntos
DNA Helicases/genética , Sequenciamento de Nucleotídeos em Larga Escala , Enzimas Multifuncionais/genética , Diester Fosfórico Hidrolases/genética , RNA Helicases/genética , Ataxias Espinocerebelares/genética , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Genes Recessivos/genética , Humanos , Lactente , Masculino , Ataxias Espinocerebelares/epidemiologia , Ataxias Espinocerebelares/patologia , Adulto JovemRESUMO
So far, over 20 causative genes of monogenic Parkinson's disease (PD) have been identified. Some causative genes of non-parkinsonian entities may also manifest with parkinsonism mimicking PD. This study aimed to investigate the genetic characteristics of clinically diagnosed PD with early onset age or family history. A total of 832 patients initially diagnosed with PD were enrolled, of which, 636 were classified into the early-onset group and 196 were classified into the familial late-onset group. The genetic testing included the multiplex ligation-dependent probe amplification and next generation sequencing (target sequencing or whole-exome sequencing). The dynamic variants of spinocerebellar ataxia were tested in probands with family history. In the early-onset group, 30.03% of patients (191/636) harbored pathogenic/likely pathogenic (P/LP) variants in known PD-related genes (CHCHD2, DJ-1, GBA (heterozygous), LRRK2, PINK1, PRKN, PLA2G6, SNCA and VPS35). Variants in PRKN were the most prevalent, accounting for 15.72% of the early-onset patients, followed by GBA (10.22%), and PLA2G6 (1.89%). And 2.52% (16/636) had P/LP variants in causative genes of other diseases (ATXN3, ATXN2, GCH1, TH, MAPT, GBA (homozygous)). In the familial late-onset group, 8.67% of patients (17/196) carried P/LP variants in known PD-related genes (GBA (heterozygous), HTRA2, SNCA) and 2.04% (4/196) had P/LP variants in other genes (ATXN2, PSEN1, DCTN1). Heterozygous GBA variants (7.14%) were the most common genetic cause found in familial late-onset patients. Genetic testing is of vital importance in differential diagnosis especially in early-onset and familial PD. Our findings may also provide some clues to the nomenclature of genetic movement disorders.
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Accumulation of α-synuclein (α-Syn) is a common pathology for both familiar and sporadic Parkinson's disease (PD), enhancing its clearance might be a promising strategy for treating PD. To assess the potential of trehalose in this regard, we investigated its effect on the PC12 cells overexpressing wild type (WT) or A53T mutant α-Syn and the implicated pathway it might mediated. We observed that trehalose promoted the clearance of A53T α-Syn but not WT α-Syn in PC12 cells, and confirmed the increased LC3 and Lysotracker RED positive autolysosomes by using lysotracker and LC3 staining, the enhanced expression of LC3-II in Western blot, and more autophagosomes under Transmission Electron Microscope in a dose dependent manner after the trehalose treatment. The activation of autophagy can be alleviated by applying macroautophagy inhibitor 3-methyladenine (3-MA). In addition, degradation of A53T and WT α-Syn was blocked after Ubiquitin Proteasome System (UPS) inhibitor (MG132) was applied in those PC12 cells overexpressing A53T or WT α-Syn, suggesting that A53T α-Syn could be degraded by both UPS and macroautophagy. But the effect of trehalose on A53T α-Syn is mainly mediated through the macroautophagy pathway, which is not a dominant way for WT α-Syn clearance. Further in vivo research will be needed to verify the effectiveness of trehalose in treating PD.
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Mutação Puntual , Trealose/farmacologia , alfa-Sinucleína/biossíntese , alfa-Sinucleína/genética , Adenina/análogos & derivados , Adenina/farmacologia , Alanina , Animais , Autofagia/efeitos dos fármacos , Western Blotting , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Imunofluorescência , Lisossomos/metabolismo , Microscopia Eletrônica de Transmissão , Células PC12 , Fagossomos/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteassoma/farmacologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Sais de Tetrazólio , Tiazóis , Treonina , Transdução Genética , Regulação para CimaRESUMO
The purpose of this study was to identify differences between genetically undefined (GU) early-onset Parkinson's disease (EOPD) patients and carriers of Parkin mutations on non-motor symptoms (NMSs). EOPD patients (N = 261) underwent targeted sequencing of Parkinson's disease (PD) related genes. Among them, 53 cases carried homozygous or compound heterozygous Parkin mutations (Parkin group) while 208 did not carry known causative PD mutations or risk factors of GBA or Parkin heterozygous mutations (GU group). NMSs were evaluated by face-to-face interviews, self-completed questionnaires and results on a neuropsychological battery. Linear regression and logistic regression models were applied to assess the predictors of NMSs. Parkin patients had younger ages of onset (AOO) (p < 0.001), longer disease durations (p < 0.001) and lower grades of Hoehn and Yarh (H&Y) (p = 0.007). Results on the neuropsychological battery showed a shorter time in Trail Making Test (TMT) (part B) in Parkin patients (p = 0.034) compared to GU patients. After adjusting for AOO, disease duration, H&Y, and levodopa equivalent daily dose (LEDD), there was a higher depression index on the Beck Depression Inventory (BDI) (p = 0.013) and better performance (p = 0.038) on executive function in the Parkin group compared to the GU group. No significant differences were found for autonomic functions, sleep-wake problems or other domains of cognitive function. Our study showed that the Parkin mutation status might be a good predictor of symptoms of depression without an impact on executive function. While these findings need to be confirmed in larger cohorts, they identify a need to screen for depression. Graphical Abstract Flow chart of genetic tests.
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Depressão/genética , Função Executiva , Mutação , Doença de Parkinson/genética , Ubiquitina-Proteína Ligases/genética , Adulto , Depressão/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações , Doença de Parkinson/psicologia , FenótipoRESUMO
Introduction: Mutations in the Parkin gene are the most common cause of autosomal recessive early-onset Parkinson's disease (PD). However, little is known about the quality of life (QoL) in Parkin-related PD. Here, we investigated the patterns of QoL in newly diagnosed Parkin-related PD patients. Methods: Newly diagnosed PD patients (diagnosis made within 12 months) who had an age of onset (AOO) below 40 and underwent a PD-related genetic testing, were recruited (n = 148). Among them, 24 patients carried bi-allelic variants in Parkin (PD-Parkin) and 24 patients did not have any known causative PD mutations, or risk variants (GU-EOPD). The clinical materials, relevant factors and determinants of QoL were analyzed. Results: PD-Parkin patients had a younger AOO (p = 0.003) and longer disease duration (p = 0.005). After adjustment for AOO and disease duration, more dystonia (p = 0.034), and worse scores of non-motor symptoms including Beck depression inventory (BDI, p = 0.035), Epworth sleepiness scale (ESS, p = 0.044), and subdomains of depression/anxiety (p = 0.015) and sleep disorders (p = 0.005) in Non-motor symptoms questionnaire, were found in PD-Parkin comparing with GU-EOPD. PD-Parkin patients had poorer QoL (adjusted p = 0.045), especially in the mobility (adjusted p = 0.025), emotional well-being (adjusted p = 0.015) and bodily discomfort dimensions (adjusted p = 0.016). BDI scores (p = 0.005) and ESS scores (p = 0.047) were significant determinants of QoL in PD-Parkin. Conclusion: Newly diagnosed PD-Parkin patients showed worse QoL. More depression and excessive daytime sleepiness predicted worse QoL. For clinicians, management of depression and excessive daytime sleepiness is suggested to better improve QoL in patients with Parkin mutations.
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OBJECTIVES: Sleep disturbances are one of the most common non-motor symptoms in Parkinson's disease (PD), and more frequently in advancing stage, almost 67-78.6% of PD patients experience some form of sleep disturbance [1-3]. Our objective is to conduct a meta-analysis of randomized controlled trials to demonstrate the efficacy and safety of rotigotine (RTG) transdermal patch for the treatment of sleep disorder in PD. METHODS: RevMan5.3 from the Cochrane Library was used to conduct a meta-analysis, primary outcome measure was score of sleep scale in Parkinson's Disease, the mean change in scores of each subscale was treated as a continuous variable and the weighted mean difference (WMD) was calculated as the difference between the mean scale of sleep score in the treatment and control groups. RESULTS: A total of five studies were included, and primary outcome measured by "PDSS" or "PDSS-2" score revealed a significant improvement in RTG treated patients compared to control [WMD: -6.66, 95% CI: (-8.54, -4.79), p < 0.0001], after the removal of two articles with high heterogeneity, the meta-analysis conclusion remained robust to methodological changes [WMD -3.90, 95%CI (-6.11, -1.69), p = 0.0005] and distinctly decreased heterogeneity was shown in the final result (I2 = 7%). CONCLUSIONS: As for the safety of RTG, it is well tolerated and safe [WMD: 1.68, 95%CI: (1.33, 2.13), p < 0.0001], application site reaction and nausea are among the most frequent side effects.
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Agonistas de Dopamina/uso terapêutico , Doença de Parkinson/complicações , Transtornos do Sono-Vigília/tratamento farmacológico , Tetra-Hidronaftalenos/uso terapêutico , Tiofenos/uso terapêutico , Adesivo Transdérmico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do TratamentoRESUMO
To investigate the usefulness of 18F-FP-CIT PET for assessing the severity of Parkinson's disease (PD) at various clinical stages, 41 patients with PD were divided into early (Hoehn&Yahr I-II, n = 23) and advanced (Hoehn & Yahr III-IV, n = 18) subgroups. 18F-FP-CIT PET was performed in these patients and 12 normal subjects. 18F-FP-CIT uptake in striatal subregions and its correlation with UPDRS were first evaluated by ROI analysis, and between-group differences were also analyzed by Statistical Parametric Mapping (SPM). Our results showed that striatal 18F-FP-CIT binding were significantly reduced to 70.9% (caudate), 46.8% (anterior putamen) and 24.0% (posterior putamen) in early PD compared with that of the control, and to 52.0%, 34.5% and 16.5% correspondingly in advanced PD, respectively. There was significant negative correlation between total motor UPDRS score of all parkinsonian patients and 18F-FP-CIT uptake in caudate nucleus (r = -0.53, p < 0.001), anterior putamen (r = -0.53, p < 0.001) and posterior putamen (r = -0.61, p < 0.001). SPM comparison of 18F-FP-CIT uptake between early or advanced PD and the control group showed significant decline in striatum, predominantly localized on the contralateral side and in the dorsal-posterior putamen. These results indicate that 18F-FP-CIT PET can serve as a suitable biomarker to represent the severity of PD in early and advanced stages.
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Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Processamento de Imagem Assistida por Computador , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/fisiopatologia , Tomografia por Emissão de Pósitrons , Índice de Gravidade de Doença , Idoso , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/patologia , Putamen/diagnóstico por imagem , Tropanos/metabolismo , UltrassonografiaRESUMO
BACKGROUND: Leucine-rich repeat kinase 2 gene (LRRK2) was recognized associated with both familial and sporadic Parkinson Disease (PD). Seven missense mutations (G2019S, R1441C, R1441G, R1441H, Y1699C, I2020T, N1437H) of it have been confirmed disease- causing. They were common among Caucasian PD patients, but rarely reported in Asian, especially in Chinese Han population. OBJECTIVES: We aimed to identify the frequencies of these seven mutations of LRRK2 in Chinese early-onset PD (EOPD) patients and analyze the phenotypes. METHODS: One hundred and thirty seven EOPD patients were enrolled for genetic testing. The seven disease-causing mutations of LRRK2 were carried out by target sequencing using Illumina HiSeq 2000 Sequencer. The identified variants were further confirmed by Sanger sequence. The clinical materials were investigated retrospectively. RESULTS: Only one patient (0.73%) was found carrying pathogenetic LRRK2 mutation of R1441C. The age at onset of the female patient was 44. She manifested typical motor symptoms of PD and responded well to levodopa therapy. Longitudinal evaluation showed progression of motor symptoms and depression but no cognitive impairment. The dopamine transporter (DAT) imaging via [11C]-2ß-carbomethoxy-3ß-(4-fluorophenyl) tropan (CFT) and Positron emission computed tomography (PET) revealed typical dopamine transporter uptake reduction. CONCLUSIONS: The LRRK2 R1441C mutation was found in a Chinese EOPD patient for the first time. The manifestations of LRRK2-R1441C carriers were indistinguishable from sporadic PD patients.
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Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Mutação , Doença de Parkinson/genética , Povo Asiático/genética , China , Seguimentos , Humanos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/fisiopatologiaRESUMO
Parkinson's disease (PD) is a common neurodegenerative disorder with high morbidity because of the coming aged society. Currently, disease management and the development of new treatment strategies mainly depend on the clinical information derived from rating scales and patients' diaries, which have various limitations with regard to validity, inter-rater variability and continuous monitoring. Recently the prevalence of mobile medical equipment has made it possible to develop an objective, accurate, remote monitoring system for motor function assessment, playing an important role in disease diagnosis, home-monitoring, and severity evaluation. This review discusses the recent development in sensor technology, which may be a promising replacement of the current rating scales in the assessment of motor function of PD.
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The present study used comparative proteomic analysis of cerebrospinal fluid (CSF) in amyotrophic lateral sclerosis (ALS) patients in order to identify proteins that may act as diagnostic biomarkers and indicators of the pathogenesis of ALS. This analysis was performed using isobaric tags for relative and absolute quantitation (iTRAQ) technology, coupled with 2-dimensional liquid chromatography/mass spectrometry. Database for Annotation, Visualization and Integrated Discovery software was utilized for bioinformatic analysis of the data. Following this, western blotting was performed in order to examine the expression of 3 candidate proteins in ALS patients compared with healthy individuals [as a normal control (NC) group] or patients with other neurological disease (OND); these proteins were insulin-like growth factor II (IGF-2), glutamate receptor 4 (GRIA4) and leucine-rich α-2-glycoprotein 1 (LRG1). Clinical data, including gender, age, disease duration and ALS functional rating scale (ALSFRS-R) score, were also collected in the ALS patients. Multiple linear regression analysis was performed between the clinical data and the results of western blot analysis. A total of 248 distinct proteins were identified in the ALS and NC groups, amongst which a significant difference could be identified in 35 proteins; of these, 21 proteins were downregulated and 14 were upregulated. These differentially-expressed proteins were thus revealed to be associated with ALS. The western blot analysis confirmed a proportion of the data attained in the iTRAQ analysis, revealing the differential protein expression of IGF-2 and GRIA4 between the ALS and NC groups. IGF-2 was significantly downregulated in ALS patients (P=0.017) and GRIA4 was significantly upregulated (P=0.016). These results were subsequently validated in the 35-patient ALS and OND groups (P=0.002), but no significant difference was identified in LRG1 expression between these groups. GRIA4 protein expression was higher in male than female patients and was positively correlated with the ALSFRS-R score, meaning that GRIA4 expression was negatively correlated with the severity of ALS, while IGF-2 and LRG1 expression did not correlate with any clinical data. The present study thus demonstrated that GRIA4 expression levels, as a marker of severity, may be used as a reference for the timing of treatment, and that IGF-2 may serve as an effective biomarker of ALS progression.
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BACKGROUND: Olfactory dysfunction is common in Parkinson's disease (PD) and idiopathic rapid eye movement sleep behavior disorder (iRBD), which is a risk factor in the development of PD. However, a few studies have conflicting results when comparing dysosmia in the patients with iRBD and PD. There is no study investigating the olfactory function in Chinese patients with iRBD. Additionally, the Sniffin' Sticks screening 12 test (SS-12) contains several odors that are not familiar to people in different cultures. METHODS: Odor identification was evaluated in iRBD patients (n = 54), PD patients (n = 54) and healthy controls (n = 54). With the identification data, a brief odor identification test was established and then validated in other subjects. RESULTS: Odor identification scores in iRBD patients were significantly higher than those in PD patients (P<0.001) but lower than those in controls (P<0.001). At the cut-off value of 7.5, the Sniffin' Sticks clearly differentiated iRBD and PD patients from the controls, and the brief test could increase the specificity in diagnosing PD. Neither the Sniffin' Sticks nor the brief test could clearly differentiate PD and iRBD patients from each other. CONCLUSIONS: Olfaction is more impaired in PD patients than in iRBD patients, possibly due to the heterogeneity of iRBD patients. The Sniffin' Sticks could be a useful tool for differentiating iRBD patients from the healthy population, and it could be useful for screening people at high-risk of PD in China, especially when combined with polysomnography. To reduce the expense and time required for the Sniffin' Sticks test, this study shows that a brief test is feasible.
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Odorantes/análise , Doença de Parkinson/diagnóstico , Transtorno do Comportamento do Sono REM/diagnóstico , Olfato , Idoso , Estudos de Casos e Controles , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Polissonografia , Transtorno do Comportamento do Sono REM/fisiopatologia , Limiar SensorialRESUMO
Mutations and excessive accumulation of α-synuclein (α-syn) can lead to the degeneration of dopaminergic neurons, indicating a pivotal role of α-syn in the pathogenesis of Parkinson's disease (PD). Although how α-syn contributes to PD is still elusive, mitochondrial impairments have been reported to be implicated in. Mortalin, a molecular chaperone mainly located in mitochondria, has been linked to the pathogenesis of PD in recent studies. Moreover, some proteomics studies indicate that mortalin is associated with PD-related proteins, including α-syn. Therefore it is of interest to understand the function of mortalin in the mitochondrial disruption induced by A53T α-syn overexpression. The present study modulated the expression of mortalin and detected the effect of mortalin on the mitochondrial impairments induced by A53T α-syn in SH-SY5Y cells. Our data revealed that A53T α-syn could disrupt mitochondrial dynamics and increase the neuronal susceptibility to neurotoxin rotenone. The expression of mortalin decreased significantly in dopaminergic cells overexpressing A53T α-syn; furthermore, the down-regulation of mortalin could attenuate the disrupted mitochondrial dynamics by reducing α-syn translocation to mitochondria, suggesting that a compensatory mechanism of mortalin might be implicated in the pathogenesis of PD.
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Proteínas de Choque Térmico HSP70/biossíntese , Mitocôndrias/metabolismo , Proteínas Mitocondriais/biossíntese , Mutação , alfa-Sinucleína/genética , Linhagem Celular Tumoral , Proteínas de Choque Térmico HSP70/genética , Humanos , Mitocôndrias/genética , Proteínas Mitocondriais/genética , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Transporte Proteico , alfa-Sinucleína/metabolismoRESUMO
PURPOSE: The young-onset subtype of Parkinson's disease (YOPD) differs from the late-onset subtype (LOPD) in drug responsiveness, incidence of motor complications, and prognosis. The pathophysiology underlying these differences remains largely unknown. This study investigated whether the two subtypes differ in the pattern of dysfunction in striatal (caudate and putamen) dopaminergic system and if the dopamine transporter (DAT) imaging patterns are associated with the clinical features of corresponding PD subtype. METHODS: We assessed the spatial pattern of striatal dopaminergic dysfunction in 40 YOPD and 47 LOPD with early to mid-stage PD with DAT imaging by positron emission tomography. Two sub-regional parameters (caudate/putamen ratio and asymmetry index) were calculated to measure the spatial pattern of striatal dopaminergic dysfunction. RESULTS: The caudate/anterior putamen ratios were significantly higher in YOPD than that in the LOPD (P = 0.03 contralateral to the most affected side of the body and P = 0.004 ipsilateral), which was supported by significantly inverse correlations between age of onset and caudate/anterior putamen ratios (r = -0.428, P < 0.001 for the contralateral and r = -0.576, P < 0.001 for the ipsilateral). Sub-regional DAT binding in caudate ipsilateral to affected limbs was significantly correlated with age, while DAT bindings in putamen were significantly inversely correlated with disease duration and UPDRS motor scores. CONCLUSION: The YOPD subtype suffers from an uneven pattern of dopaminergic dysfunction: more sparing of the caudate compared with the putamen, while the LOPD patients is with a relatively uniform pattern.
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Núcleo Caudado/diagnóstico por imagem , Proteínas da Membrana Plasmática de Transporte de Dopamina/análise , Neurônios Dopaminérgicos/diagnóstico por imagem , Neuroimagem/métodos , Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Putamen/diagnóstico por imagem , Adulto , Idade de Início , Idoso , Radioisótopos de Carbono/análise , Radioisótopos de Carbono/farmacocinética , Núcleo Caudado/química , Núcleo Caudado/patologia , Cocaína/análogos & derivados , Cocaína/análise , Cocaína/farmacocinética , Neurônios Dopaminérgicos/química , Neurônios Dopaminérgicos/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Especificidade de Órgãos , Doença de Parkinson/classificação , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Putamen/química , Putamen/patologia , Compostos Radiofarmacêuticos/análise , Compostos Radiofarmacêuticos/farmacocinética , Distribuição TecidualRESUMO
To investigate the characteristics of alpha-synucleinopathy in the brains of centenarians, the autopsied brains and spinal cords from 23 cases were studied. Coronal slices were prepared from a section of the cerebral hemisphere, following the guidelines of the Consortium to Establish a Registry for Alzheimer's Disease (AD) (CERAD) and the consensus guidelines for the clinical and pathologic diagnosis of dementia with Lewy bodies (DLB). Spinal cord specimens were prepared at each segment from the third cervical to the third sacral segment. In all cases, we performed standard stainings of hematoxylin-eosin, Klüver-Barrera, and Gallyas-Braak combined with Luxol fast blue/cresyl violet, and alpha-synuclein (AS), phosphorylated tau (AT8) and beta-amyloid protein immunostainings. One-way ANOVA analysis, Chi-square or Fisher exact test were used for statistical analysis. Overall, AS-positive structures were found in 8 (34.8%) of our 23 centenarians, 6 (35.3%) of 17 demented patients, and four (40%) out of ten AD patients. The frequencies of AS lesions in the brains with senile plaque (SP) stage 0-A, B, and C were 27.7, 33, and 50%, respectively. No statistical differences were found among the frequencies of AS lesions in the subgroups of NFT stages I-II, III-IV, and V-VI (P=0.478). Most cases showed a widespread distribution of AS-positive structures except for one patient, in whose brain only the medulla was involved. The distribution pattern of AS-positive lesions was similar to that in Parkinson's disease or DLB, but the pigmented neurons in substantia nigra were relatively well preserved. Our findings indicate that there is a high frequency of alpha-synucleinopathy in centenarians, SP-positive and AS-positive lesions may involve a synergistic interaction.
Assuntos
Idoso de 80 Anos ou mais , Encéfalo/metabolismo , alfa-Sinucleína/metabolismo , Autopsia , Encéfalo/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Índice de Gravidade de Doença , Medula Espinal/metabolismo , Medula Espinal/patologia , Substância Negra/metabolismo , Substância Negra/patologia , alfa-Sinucleína/genéticaRESUMO
Argyrophilic grain disease (AGD) is a progressive degenerative disease of the human brain, the prevalence of which increases with advancing age. The features of AGD in autopsied brains from 32 centenarians were studied using phosphorylated tau (AT8) immunostaining combined with Gallyas-Braak staining and 4R tau-specific antibody (RD4) immunostaining. Ten of 32 centenarians were diagnosed as AGD, yielding an overall frequency of 31.3%. In the demented group, nine (39.1%) of 23 cases were found with argyrophilic grains (AGs), while in the non-demented group, AGs were found in only one (11.1%) of nine cases, the difference between them being significant (P<0.05). Among the cases with Alzheimer's disease (AD), five (41.7%) of 12 were found with AGs. One (25%) of four cases with senile dementia with tangles (SDT) also suffered from AGD. Dementia caused by "pure" AGD accounted for 13% (3/23) among demented subjects. Our findings indicated that there is a high frequency of AGD in centenarians. In agreement with previous studies, we favor the view that age may be one of the risk factors for AGD.