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El diagnóstico de enfermedad de Parkinson (ED) se basa en las principales manifestaciones motoras: bradicinesia en combinación con temblor en reposo, rigidez o ambos. Cuando se realiza el diagnóstico basado en la sintomatología motora clínica típica ya se han perdido hasta el 60 % de las neuronas dopaminérgicas de la sustancia negra pars compacta mesencefálica. La identificación de los síntomas premotores son un marcador temprano para sospechar la aparición futura de la enfermedad, así como su progresión y gravedad. La hipótesis sobre la patogénesis que mejor expone la progresión de la enfermedad es la teoría de Braak. Esta se basa en la aparición y presencia de cuerpos de Lewy en diferentes estructuras anatómicas, las cuales representadas en cada uno de sus seis estadios y podrían ser la explicación biológica de los síntomas premotores, motores y no motores. La detección temprana de los síntomas premotores puede tener repercusiones positivas en el enfoque, seguimiento, diagnóstico y tratamiento de la EP. El propósito de este artículo es identificar las aproximaciones neurológicas descritas por la teoría de Braak para los síntomas premotores de la enfermedad de Parkinson de acuerdo con la literatura publicada en los últimos 20 años.
The diagnosis of Parkinson's disease (PD) is based on the main motor manifestations: bradykinesia in combination with tremor at rest, rigidity, or both. When the diagnosis is made based on typical clinical motor symptoms, up to 60 % of the dopaminergic neurons of the mesencephalic substantia nigra pars compacta have already been lost. The identification of premotor symptoms is an early marker to suspect the future appearance of the disease, as well as its progression and severity. The hypothesis about the pathogenesis that best exposes the progression of the disease is Braak's theory. It is based on the appearance and presence of Lewy bodies in different anatomical structures, which are represented in each of its six stages and could be the biological explanation biological of premotor, motor, and non-motor symptoms. Early detection of premotor symptoms can have positive repercussions in the approach, follow-up, diagnosis and treatment of PD. The purpose of this article is to identify the neurological approaches described by Braak's theory for the premotor symptoms of Parkinson's disease according to the literature published in the last 20 years.
O diagnóstico da doença de Parkinson (DP) baseia-se nas principais manifestações motoras: bradicinesia combinada com tremor de repouso, rigidez ou ambos. Quando o diagnóstico é feito com base em sintomas clínicos motores típicos, até 60% dos neurônios dopaminérgicos da substância negra pars compacta mesencefálica já foram perdidos. A identificação de sintomas pré-motores é um marcador precoce para suspeitar do futuro aparecimento da doença, bem como da sua progressão e gravidade. A hipótese sobre a patogênese que melhor expõe a progressão da doença é a teoria de Braak. Isto se baseia no aparecimento e presença de corpos de Lewy em diferentes estruturas anatômicas, que estão representados em cada uma de suas seis etapas e podem ser a explicação biológica dos sintomas pré-motores, motores e não motores. A detecção precoce de sintomas pré-motores pode repercutir positivamente na abordagem, acompanhamento, diagnóstico e tratamento da DP. O objetivo deste artigo é identificar as abordagens neurológicas descritas pela teoria de Braak para os sintomas pré-motores da doença de Parkinson de acordo com a literatura publicada nos últimos 20 anos.
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Humans , Adult , Middle Aged , Aged , Aged, 80 and overABSTRACT
Background Increasing evidence suggests a double-faceted role of alpha-synuclein (α-syn) following infection by a variety of viruses, including SARS-CoV-2. Although α-syn accumulation is known to contribute to cell toxicity and the development and/or exacerbation of neuropathological manifestations, it is also a key to sustaining anti-viral innate immunity. Consistently with α-syn aggregation as a hallmark of Parkinson's disease, most studies investigating the biological function of α-syn focused on neural cells, while reports on the role of α-syn in periphery are limited, especially in SARS-CoV-2 infection. Results Results herein obtained by real time qPCR, immunofluorescence and western blot indicate that α-syn upregulation in peripheral cells occurs as a Type-I Interferon (IFN)-related response against SARS-CoV-2 infection. Noteworthy, this effect mostly involves α-syn multimers, and the dynamic α-syn multimer:monomer ratio. Administration of excess α-syn monomers promoted SARS-CoV-2 replication along with downregulation of IFN-Stimulated Genes (ISGs) in epithelial lung cells, which was associated with reduced α-syn multimers and α-syn multimer:monomer ratio. These effects were prevented by combined administration of IFN-β, which hindered virus replication and upregulated ISGs, meanwhile increasing both α-syn multimers and α-syn multimer:monomer ratio in the absence of cell toxicity. Finally, in endothelial cells displaying abortive SARS-CoV-2 replication, α-syn multimers, and multimer:monomer ratio were not reduced following exposure to the virus and exogenous α-syn, suggesting that only productive viral infection impairs α-syn multimerization and multimer:monomer equilibrium. Conclusions Our study provides novel insights into the biology of α-syn, showing that its dynamic conformations are implicated in the innate immune response against SARS-CoV-2 infection in peripheral cells. In particular, our results suggest that promotion of non-toxic α-syn multimers likely occurs as a Type-I IFN-related biological response which partakes in the suppression of viral replication. Further studies are needed to replicate our findings in neuronal cells as well as animal models, and to ascertain the nature of such α-syn conformations.
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ABSTRACT Background: In Parkinson's disease (PD), exosomes carry α-synuclein (α-syn), a fibrillar protein aggregates with potential value as a biomarker. Objective: Evidence on blood levels of exosomal α-syn in PD patients and controls was reviewed for their consistency. Methods: Thirty-six studies on exosomal α-syn concentrations in PD were identified in a systematic literature search and meta-analysis. Results: Both raw and ratio-adjusted blood exosomal α-syn levels were consistently higher in PD patients than in controls. The standardized mean difference (SMD) was 1.54 (0.18-2.90, CI95%, p < 0.01) and 1.53 (0.23-2.83, CI95%, p < 0.01), respectively. Conclusion: Our results suggest that exosomal α-syn concentrations could be a useful biomarker for PD.
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Parkinson′s disease (PD) is the most common age-related neurodegenerative disease, which has the effects on the patients′ quality of life and brings a huge burden to the society and family. The pathological feature of PD is the abnormal accumulation of alpha-synuclein (α-syn) in the brain of substantia nigra-striatum, mediating the death of dopaminergic neurons. However, further studies have found that α-syn mediates the abnormal function of astrocytes leading to the destruction of the blood-brain barrier and the release of inflammatory factors caused by microglia, which are related to the pathogenesis of PD. Therefore, neurons, glial cells, and blood vessels as a whole named neurovascular unit can better reflect the pathophysiological environment of PD and reveal the PD pathogenesis. Studies have detected the ways of α-syn transmission, such as prion-like, tunneling nanotubes, exosomes, are connected with the pathogenesis and progression of PD. The Braak stage and the prospective cohort of early PD provide a view that the peripheral α-syn to the central nervous system may be an another important way to mediate the pathogenesis and progression of PD. The research about the abnormal aggregation and spread of α-syn can provide the new theory for the pathogenesis of PD and the new disease modifying therapy of PD. This article reviews the role of abnormal aggregation and transmission of α-syn in the pathogenesis of PD.
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Parkinson's disease(PD)is a progressive neurodegenerative disorder that tends to occur in the elderly.Its clinical manifestations mainly include motor symptoms and non-motor symptoms, with sleep disorders among common non-motor symptoms of PD.The latest lines of evidence show that sleep disorders are not only clinical manifestations of neurodegenerative diseases, but also an important risk factor for the development and progression of neurodegenerative diseases.There is a bidirectional relationship between sleep disorders and neurodegenerative diseases, including PD.The possible mechanisms include accelerated α-synuclein pathology, deposition of Tau protein, inhibition of the glymphatic system, neuroinflammation and changes in the circadian rhythm system.In this article, we review research progress on the bidirectional relationship between sleep disorders and PD, related mechanisms, and the outlook on the treatment of PD through the management of sleep disorders.
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Background Paraquat (PQ), one of the environmental poisons associated with sporadic Parkinson's disease (PD), can cause abnormal aggregation of alpha-synuclein (α-syn), but the research on its conformational changes and subcellular localization is limited. Objective To investigate the effect of PQ on α-syn conformation and subcellular localization in dopaminergic neurons. Methods Forty-eight SPF C57BL/6 male mice were selected and randomly divided into a control group and a model group. The model group was intraperitoneally injected with PQ (15 mg·kg−1), and the control group was intraperitoneally injected with 0.9% normal saline, twice a week for eight weeks to construct a PD-like mouse model. The changes of neurobehavior (by open field test and pole climbing test) were observed to evaluate motor ability of mice. Immunohistochemical staining (IHC) was used to detect the expression levels of tyrosine hydroxylase (TH) and α-syn in the midbrain. Western blotting (WB) was used to measure the protein expression levels of TH and α-syn in midbrain. Human neuroblastoma SH-SY5Y cells were used as dopaminergic neuron in vitro models. After the cells were treated with PQ (100 μmol·L−1) for 0, 12, 24, 36 and 48 h, the expressions of α-syn in whole cell, cytoplasm, and nucleus were detected by WB; the expression level of extracellular α-syn was detected by enzyme-linked immunosorbent assay (ELISA); the change of α-syn location was observed by immunofluorescence assay (IFA). Results The neurobehavioral tests' results showed that compared with the control group, the residence time in peripheral area of mice in the PQ model group increased with the increase of exposure time (P<0.05), the residence time and moving distance in the central region decreased (P<0.05), and the pole climbing time increased (P<0.05). The mouse IHC results showed that compared with the control group, the number of TH positive cells in the midbrain decreased in the model group at week 6 and 8 (P<0.05), while the expression level of α-syn increased at week 4, 6, and 8 (P<0.05). The WB results of mouse showed that the relative expression of TH decreased significantly after 6 and 8 weeks of PQ exposure (P<0.05), and the relative expression of oligomer α-syn increased after 4, 6, and 8 weeks of PQ exposure (P<0.05). The WB of in vitro models results showed that the relative expression of α-syn in cells increased with time (R2=0.7440, P<0.05); the relative expression of α-syn in cytoplasm increased firstly and then decreased with time (P<0.05); the relative expression of α-syn in nucleus increased with time (R2=0.7913, P<0.05). The IFA results of in vitro models showed that the expression of oligomerized α-syn increased and translocated to the nucleus (P<0.05). The ELISA results of in vitro models showed that α-syn increased with the increase of PQ exposure time (P<0.05). Conclusion PQ can increase the expression of α-syn in dopaminergic neurons, induce oligomerization and translocation to the nucleus.
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Parkinson′s disease is a degenerative disease of the central nervous system with abnormal protein deposition in the brain as the main pathological changes. The onset of Parkinson′s disease is related to abnormal deposition protein removal disorders, and the relevant mechanisms are still unclear. The glymphatic system is a metabolic waste and abnormal protein deposition removal system in the brain. In recent years, studies have shown that the changes of aquaporin 4, perivascular space and dural lymphatic vessels in Parkinson′s disease are closely related to the level of relevant pathological proteins in cerebrospinal fluid, leading to the occurrence and development of Parkinson′s disease. The researches on structure and biomarkers of the glymphatic system in Parkinson′s disease in recent years are reviewed in this article.
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Objective: To observe the dynamic changes of brainstem locus coeruleus (LC) damage in Parkinson' s disease (PD) -like mice by paraquat (PQ) . Methods: In October 2019, 36 male C57BL/6 mice were randomly divided into the exposure group and the control group, with 18 mice in each group. The mice in the exposure group were given intraperitoneal injection of 15 mg/kg PQ, and the mice in the control group were given intraperitoneal injection of 0.9% saline, twice a week for 8 weeks. Neurobehavioral changes (pole climbing test, swimming test, open field test, tail hanging test, high plus maze test and water maze test) were observed at 4 weeks, 6 weeks and 8 weeks, respectively, and the changes of motor ability, emotion and cognitive function were evaluated. The brain tissue of mice were taken and stained with Hematoxylin-Eosin (HE) to observe the pathological changes of LC. Nissl staining was used to detect the changes of neuronal Nissl bodies in LC. Immunohistochemistry (IHC) staining was used to detect the expression of neuron nuclear antigen (NeuN) , dopamine (DA) neurons and norepinephrine (NE) neuron markers tyrosine hydroxylase (TH) , α-synuclein (α-syn) in substantia nigra (SN) and LC. The expression levels of NeuN, TH and α-syn in the midbrain and brainstem were detected by Western blotting. TUNEL staining was used to detect neuronal apoptosis in LC. Results: Compared with the 4th week of PQ exposure group, the time of pole climbing and swimming immobility were gradually increased, the ratio of open arm residence time of high plus maze test and the number of times of the platform and the residence time of platform quadrant in water maze test were gradually decreased (P<0.05) in the exposure group with the progress of exposure time. The results of HE and Nissl staining showed that the neurons in LC gradually arranged loosely, the nucleus were deeply stained, the cytoplasm was pyknosis, and the number of Nissl bodies gradually decreased (P<0.05) in the exposure group with the progress of exposure time. IHC results showed that the number of NeuN and TH positive cells in SN and LC of mice were gradually decreased, and the positive expression of α-syn was gradually increased (P<0.05) in the exposure group with the progress of exposure time. Western blotting results showed that the expression levels of NeuN and TH in the midbrain and brainstem were gradually decreased, and the expression level of α-syn was gradually increased (P<0.05) in the exposure group with the progress of exposure time. TUNEL staining showed that the apoptosis rates of neurons in LC were gradually increased (P<0.05) in the exposure group with the progress of exposure time. Conclusion: PQ induces progressive damage in the LC area of PD-like mice, which may be caused by the abnormal accumulation of pathological α-syn in the LC area.
Subject(s)
Animals , Male , Mice , Dopaminergic Neurons , Locus Coeruleus/pathology , Mice, Inbred C57BL , Paraquat/toxicity , Parkinson Disease/metabolism , Substantia Nigra , Tyrosine 3-Monooxygenase/metabolismABSTRACT
Objective:To evaluate the effects of propofol on inflammatory responses in substantia nigra in mice with Parkinson′s disease (PD) and its relationship with α-synuclein (α-syn) expression.Methods:Thirty-three SPF healthy male C57BL/6 mice, aged 12 weeks, weighing 24-26 g, were divided into 3 groups ( n=11 each) using a random number table method: control group (group Con), group PD and propofol group (group Pro). In PD and Pro groups, 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) 30 mg/kg was intraperitoneally injected once a day for 5 consecutive days to induce PD.Propofol 50 mg/kg was intraperitoneally injected at 2 h after the last injection of MPTP in group Pro, while the equal volume of normal saline was given instead in Con and PD groups.The rotarod test was performed at 24 h after administration.The animals were then sacrificed and substantia nigra was removed for determination of contents of interleukin-1β (IL-1β) and tumor necrosis factor (TNF)-α (by enzyme-linked immunosorbent assay), the expression of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) and p-caspase-1 (by Western blot) and the expression of α-syn (by immunofluorescence staining). Results:Compared with Con group, the first fall-off time was significantly shortened, the number of falling off was increased, the contents of IL-1β and TNF-α were increased, and the expression NLRP3, p-caspase-1and α-syn was up-regulated in substantia nigra in group PD ( P<0.05). Compared with PD group, the first fall-off time was significantly prolonged, the number of falling off was decreased, the contents of IL-1β and TNF-α were decreased, and the expression NLRP3, p-caspase-1and α-syn was down-regulated in substantia nigra in group Pro ( P<0.05). Conclusion:Propofol can improve behaviors of the mice through inhibiting inflammatory responses in substantia nigra, and the mechanism is related to down-regulating the expression of α-syn.
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Objective:To investigate the value of α-synuclein (α-syn) concentration in cerebrospinal fluid (CSF) in predicting postoperative delirium (POD).Methods:One thousand patients underwent elective surgery with combined epidural-spinal anesthesia in our hospital from January 2018 to September 2020 were selected.The epidural puncture was performed at L 3, 4 interspace, and 2 ml of CSF was collected after the needle reaching the subarachnoid space.The concentrations of α-syn, β-amyloid (Aβ)40, Aβ42, total tau protein (T-tau), and phosphorylated tau protein (P-tau) in CSF were determined by enzyme-linked immunosorbent assay.The concentrations of α-syn in CSF and occurrence of POD in patients of different ages were recorded.Patients were divided into POD group and non-POD group according to whether POD occurred, and frequency matching (1∶1) was performed based on five matching variables of age, ASA physical status, education level, duration of operation, and intraoperative blood loss. Results:Eight hundred and forty-one patients were finally included in the study, and the incidence of POD was 15.0%. There were 126 cases in POD group and 126 cases in non-POD group after matching. The concentrations of α-syn in CSF and incidence of POD were gradually increased with age ( P<0.05). Compared with non-POD group, the concentrations of α-syn, T-tau and P-tau in CSF were significantly increased, the concentrations of Aβ40 and Aβ42 were decreased, Aβ40/P-tau, Aβ42/P-tau, Aβ42/Aβ40 and P-tau/T-tau were decreased in POD group ( P<0.05). After confounding factors were corrected by logistic regression analysis, increased concentrations of α-syn, p-tau, and T-tau in CSF were risk factors for POD ( P<0.05). Increased concentrations of Aβ40 and Aβ42 in CSF and increased Aβ40/P-tau and Aβ42/P-tau were protective factors for POD ( P<0.05). Multiple linear regression analysis showed that the concentration of α-syn in CSF was negatively correlated with Aβ40 and Aβ42 concentrations and positively correlated with P-tau and T-tau concentrations ( P<0.05). The area under the receiver operating characteristic curve of concentrations of α-syn in CSF predicting POD was 0.895, Youden index was 0.664, sensitivity was 80.00%, and specificity was 86.36% ( P<0.001). Conclusion:The concentration of α-syn in CSF is related to the occurrence of POD, and it provides higher accuracy in predicting POD.
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Parkinson′s disease (PD) is a neurodegenerative disease commonly found in middle-aged and elderly people. It is characterized by resting tremor, bradykinesia, myotonia, and abnormal posture gait. The main pathological changes were the loss of dopaminergic neurons in the substantia nigra and the formation of Lewy bodies in the cytoplasm of the residual neurons. The main component of the Lewy bodies was α-synuclein. And why it causes the degeneration of dopaminergic neurons in the substantia nigra is not known. At present, most studies on Parkinson′s disease focus on the pathogenesis of the disease. More and more evidence shows that respiratory chain injury is a key feature of sporadic PD patients, and the proteins encoded by PD-related genes are related to the disorder of mitochondrial function. We believe that the important mechanism of the disease is impaired mitochondrial function due to environmental and (or) genetic inheritance. This article highlights new advances in mitochondrial dysfunction in Parkinson′s pathogenesis, including mitochondria and cell-mediated immunity, endoplasmic reticulum (ER)-mitochondrial axis, sirtuin-mediated mitochondrial stress response, and the role of microRNA in the etiology of PD. A deeper understanding of these mechanisms may provide inspiration for the development of new targeted therapies.
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Introducción. El consumo excesivo de alcohol resulta en neuroadaptación, neurodegeneración y expresión diferencial de numerosos genes. Objetivo. Determinar la relación entre la expresión del gen de la alfa sinucleína (SNCA) en sangre, las variantes de nucleótido único (Single Nucleotide Variant, SNV) en su región promotora y el estreñimiento crónico en personas con problemas de consumo de alcohol. Materiales y métodos. La muestra estuvo conformada por 35 controles y 27 casos, seleccionados según el puntaje obtenido con la herramienta AUDIT. En el diagnóstico del estreñimiento se aplicaron los criterios de Roma IV. La extracción de ácidos nucleicos se hizo a partir de sangre periférica y se evaluó la expresión del gen mediante qPCR, la cuantificación proteica por ELISA y la presencia de SNV en la región promotora del gen por la secuenciación de Sanger. Resultados. Se observó sobreexpresión génica relativa de ARNm del gen SNCA en el grupo de casos sin relación con el estreñimiento crónico. Se evidenció un riesgo 4,8 veces mayor de presentar estreñimiento en el grupo de casos. Se encontraron nueve variantes de nucleótido simple en un segmento de la región promotora del gen rica en secuencias reguladoras CpG, con frecuencia similar entre los grupos, y se detectó una variante en la posición -2171 que no se encuentra reportada en GenBank para variantes clínicas y cuyo genotipo A/T se relacionó con el incremento de la expresión del ARNm del SNCA. Conclusión. En personas con problemas de consumo de alcohol se evidenció la sobreexpresión del ARNm de alfa sinucleína, lo cual no se relacionó con el diagnóstico de estreñimiento crónico.
Introduction: Excessive alcohol consumption results in neuroadaptation, neurodegeneration, and differential expression of numerous genes. Objective: To determine the relationship between the expression of the alpha synuclein gene (SNCA) in blood, single nucleotide variant (SNV) in its promoter region, and chronic constipation in people with problems of alcohol consumption. Materials and methods: The sample consisted of 35 controls and 27 cases selected according to the score obtained with the AUDIT tool. For the diagnosis of constipation, the Rome IV criteria were applied. Nucleic acid extraction was performed from peripheral blood and the expression of the gene was evaluated by qPCR, protein quantification by ELISA, and the presence of SNV in the promoter region of the gene by Sanger sequencing. Results: We observed a relative gene overexpression of SNCA mRNA in the case group, which was not related to the diagnosis of chronic constipation. There was 4.8 times greater risk of presenting constipation in the group of cases. Besides, nine single nucleotide variants were found in a segment of the promoter region of the gene rich in CpG regulatory sequences with similar frequency between the groups while a variant was identified in position -2171, which is not reported in GenBank for variants and whose genotype A/T was associated with increased expression of SNCA mRNA. Conclusion: We evidenced an overexpression of alpha synuclein mRNA in people with problems of alcohol consumption that was not related to the diagnosis of chronic constipation.
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Constipation , Alcoholism , alpha-Synuclein , Polymorphism, Genetic , Gene Expression , InflammationABSTRACT
OBJECTIVE@#To analyze the effect of benzopyrene on the decrease of dopaminergic neurons, and the increase and aggregation of α-synuclein, which are the pathological features of Parkinson's disease, and to explore its possible mechanisms.@*METHODS@#Eight-month-old transgenic mice with human SNCA gene were randomly divided into a BaP-exposed group and a control group. BaP and solvent corn oil were injected intraperitoneally to BaP-exposed group and control group respectively, once a day for 60 days. The motor dysfunction of mice was tested by rotarod test. The effects of BaP on the decrease of dopaminergic neurons and increase and aggregation of α-synuclein were observed by immunohistochemistry and Western blot experiments respectively, and the expression of related mRNA was detected by quantitative real-time PCR (qRT-PCR). Twenty genes were tested in the study, mainly related to neurotransmitter transporter (2 genes), neurotransmitter receptor function (10 genes), cellular autophagy (5 genes), and α-synuclein aggregation and degradation (3 genes).@*RESULTS@#After BaP exposure, the movement time of the mice in the rotarod test was significantly reduced (P<0.05). The substantia nigra dopami-nergic neurons in the mice were significantly reduced, which was 62% of the control group (P<0.05), and the expression of α-synuclein in the midbrain increased, which was 1.36 times that of the control group (P<0.05). After BaP exposure, mRNA expressions of 14 genes in the midbrain of the mice were significantly down-regulated (P<0.05). Alpha-synuclein degradation and cell autophagy (5 genes), neuron transporters (2 genes), and neurotransmitter receptor functions (5 genes) were involved. The expression of one gene, Synphilin-1, was significantly up-regulated (P<0.01), which was related to α-synuclein aggregation.@*CONCLUSION@#BaP exposure not only inhibited function of neurotransmitter receptor and dopamine transporter, but also interfered cell autophagy, thereby hindering the degradation of α-synuclein, which could lead to decrease of dopaminergic neurons in substantia nigra and increase and aggregation of α-synuclein in midbrain, as the significant pathology of Parkinson's disease. Therefore, BaP exposure may increase the risk of Parkinson's disease.
Subject(s)
Animals , Humans , Mice , Benzo(a)pyrene , Brain , Dopamine , Dopaminergic Neurons , alpha-SynucleinABSTRACT
Parkinson's disease (PD) is a progressive degenerative disease of the central nervous system,which is characterized by the aggregation of alpha-synuclein.Accumulating evidence suggests that PD may arise in the gut.Aggregation of alpha-synuclein was found in the enteric nervous system of patients with prodromal stage of PD,alpha-synuclein might spread from the enteric nervous system to the centralnervous system through vagus nerve based on animal model.The increased permeability and oxidative stress of gut may also be associated with the aggregation of alpha-synuclein and its propagation from gut to the central nerve system.
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Objective To study the relationship between plasma neurodegenerative protein level and non-motor symptoms(NMS)in PD patients.Methods Eighty-four PD patients served as a PD group and 54age-matched persons undergoing physical examination served as a control group. The NMS of PD patients were assessed according to the HAMD scale.The plasma levels of tau,p-tau181,Aβ-42andα-syn were measured by ELISA and analyzed by Spearman correlation analysis and binary logistic regression analysis respectively.Results The FSS score and plasmaα-syn level were significantly higher while the plasma Aβ-42level was significantly lower in PD group than in control group(3.22±1.68 vs 1.89±1.16,P=0.000;320.00±64.91ng/L vs 277.78±52.75ng/L,P=0.000;267.61±77.75ng/L vs 321.80±49.41ng/L,P=0.001).No significant difference was detected in plasma tau and p-tau181levels between the two groups(P＞0.05).The plasmaα-syn level was positively related with the FSS score(r=0.237,P=0.030)and was an influencing factor of FSS(OR=1.019,95％CI:1.006-1.032,P=0.004).Conclusion Plasma neurodegenerative protein level is related with NMS and plasmaα-syn level is a peripheral biomarker for fatigue in PD patients.
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The aggregation of α-synuclein (α-syn) has been implicated in the pathogenesis of many neurodegenerative disorders, including Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). Postmortem analyses of α-syn pathology, especially that of PD, have suggested that aggregates progressively spread from a few discrete locations to wider brain regions. The neuron-to-neuron propagation of α-syn has been suggested to be the underlying mechanism by which aggregates spread throughout the brain. Many cellular and animal models has been created to study cell-to-cell propagation. Recently, it has been shown that a single injection of preformed fibrils (PFFs) made of recombinant α-syn proteins into various tissues and organs of many different animal species results in widespread α-syn pathology in the central nervous system (CNS). These PFF models have been extensively used to study the mechanism by which aggregates spread throughout the brain. Here, we review what we have learned from PFF models, describe the nature of PFFs and the neuropathological features, neurophysiological characteristics, and behavioral outcomes of the models.
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Animals , alpha-Synuclein , Brain , Central Nervous System , Dementia , Lewy Bodies , Models, Animal , Multiple System Atrophy , Neurodegenerative Diseases , Parkinson Disease , PathologyABSTRACT
BACKGROUND AND PURPOSE: It is essential to develop a reliable predictive serum biomarker for Parkinson's disease (PD). The accumulation of alpha-synuclein (αSyn) and up-regulated expression of Rab35 participate in the etiology of PD. The purpose of this investigation was to determine whether the combined assessment of serum αSyn and Rab35 is a useful predictive biomarker for PD. METHODS: Serum levels of αSyn or Rab35 were determined in serum samples from 59 sporadic PD patients, 19 progressive supranuclear palsy (PSP) patients, 20 multiple system atrophy (MSA) patients, and 60 normal controls (NC). Receiver operating characteristics (ROC) curves were calculated to determine the diagnostic accuracy of αSyn or/and Rab35 in discriminating PD patients from NC or atypical parkinsonian patients. RESULTS: The levels of αSyn and Rab35 were increased in PD patients. The serum level of Rab35 was positively correlated with that of αSyn in PD patients. Compared to analyzing αSyn or Rab35 alone, the combined analysis of αSyn and Rab35 produced a larger area under the ROC curve and performed better in discriminating PD patients from NC, MSA patients, or PSP patients. When age was dichotomized at 55, 60, 65, or 70 years, the combined assessment of αSyn and Rab35 for classifying PD was better in the group below the cutoff age than in the group above the cutoff age. CONCLUSIONS: Combined assessment of serum αSyn and Rab35 is a better biomarker for discriminating PD patients from NC or atypical parkinsonian patients, and is a useful predictive biomarker for younger sporadic PD patients.
Subject(s)
Humans , alpha-Synuclein , Multiple System Atrophy , Parkinson Disease , ROC Curve , Supranuclear Palsy, ProgressiveABSTRACT
Dementia with Lewy bodies(DLB) is the second most common neurodegenerative disease. However, DLB might not be adequately diagnosed due to its variety of clinical symptoms. The authors present 65-year-old Mrs. A. who showed Parkinson's movement, cognitive decline, psychological symptoms, and autonomic dysfunction. According to the clinical features and biological markers in the recently revised DLB criteria, Mrs. A. was diagnosed with probable DLB. Differential diagnoses of delirium, Parkinson's dementia, and Alzheimer's dementia were discussed. Psychopharmacological treatments of antidepressants or anxiolytics caused intolerable side effects and showed little efficacy to Mrs. A. She experienced two episodes of hyponatremia during her one-year treatment. Recovery from neurological symptoms due to the first hyponatremia was time-consuming, and in the second, it was associated with changes in the level of consciousness despite relatively mild hyponatremia. A fall that occurred in the latter part of treatment triggered remarkable deterioration of DLB symptoms and daily life function. Prevention of falls is important for maintaining the quality of life of patients with DLB.
Subject(s)
Aged , Humans , Accidental Falls , alpha-Synuclein , Anti-Anxiety Agents , Antidepressive Agents , Biomarkers , Consciousness , Delirium , Dementia , Diagnosis , Diagnosis, Differential , Hyponatremia , Lewy Bodies , Neurodegenerative Diseases , Quality of LifeABSTRACT
Objective To establish an in vitro cell model of Parkinson disease with SHSY5Y cells over-expressing human A53T mutant alpha-synuclein and to examine the effects of Aβ1-42 oligomer on cell survival and autophagy function in the cell model Method The recombinant lentivirus containing the A53T mutant alpha-synuclein gene or empty vector were transfected to SHSY5Y cells. The expression of α-synuclein mRNA in SHSY5Y cells was detected by RT-qPCR. The effect of Aβ1-42 oligomer on cell proliferation was detected with CCK-8 after incubation with Aβ1-42 oligomer for 24 hours. The autophagy-related proteins were evaluated with Western Blot. Result The mRNA and protein levels of alpha-synuclein were significantly increased in SHSY5Y cells expressing alpha-synuclein. There were no significant difference in the cell proliferation between alpha-synuclein group and control group (P<0.001) . Incubation with Aβ1-42 oligomer significantly decreased the proliferation rate in alpha-synuclein group in a dose-dependent manner compared with the control group. The levels of autophagy related proteins including LC3-Ⅱ and Beclin-1 were significantly lower in alpha-synuclein group than in control group (P<0.05). Conclusion This work has constructed an in vitro cell model of Parkinson′s disease. The over-expression of A53T mutant alpha-synuclein do not affect the cell survival whereas the Aβ1-42 oligomer exhibits toxic effects on cells expressing alpha-synuclein possible through suppression of the autophagy activation.
ABSTRACT
ABSTRACT Current understanding of the pathophysiology of Parkinson's disease suggests a key role of the accumulation of alpha-synuclein in the pathogenesis. This critical review highlights major landmarks, hypotheses and controversies about the origin and progression of synucleinopathy in Parkinson's disease, leading to an updated review of evidence suggesting the enteric nervous system might be the starting point for the whole process. Although accumulating and compelling evidence favors this theory, the remaining knowledge gaps are important points for future studies.
RESUMO O atual entendimento sobre a fisiopatologia da doença de Parkinson (DP) sugere um papel central do acúmulo de alfa-sinucleína na patogenia da DP Esta revisão crítica revisita marcos, teorias e controvérsias a respeito da origem e progressão da sinucleinopatia, apresentando uma atualização das principais evidências sugerindo que o sistema nervoso entérico seria o local inicial deste processo. Apesar das evidências a favor desta teoria serem crescentes e instigantes, as lacunas de conhecimento a este respeito são importantes pontos para estudos futuros.