ABSTRACT
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.
Subject(s)
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.
ABSTRACT
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.
ABSTRACT
The accumulation of pathological α-synuclein (α-syn) in the central nervous system and the progressive loss of dopaminergic neurons in the substantia nigra pars compacta are the neuropathological features of Parkinson's disease (PD). Recently, the findings of prion-like transmission of α-syn pathology have expanded our understanding of the region-specific distribution of α-syn in PD patients. Accumulating evidence suggests that α-syn aggregates are released from neurons and endocytosed by glial cells, which contributes to the clearance of α-syn. However, the activation of glial cells by α-syn species produces pro-inflammatory factors that decrease the uptake of α-syn aggregates by glial cells and promote the transmission of α-syn between neurons, which promotes the spread of α-syn pathology. In this article, we provide an overview of current knowledge on the role of glia and α-syn pathology in PD pathogenesis, highlighting the relationships between glial responses and the spread of α-syn pathology.
Subject(s)
Humans , Parkinson Disease/pathology , alpha-Synuclein/metabolism , Dopaminergic Neurons/metabolism , Pars Compacta/metabolismABSTRACT
The way sporadic Parkinson's disease (PD) is perceived has undergone drastic changes in recent decades. For a long time, PD was considered a brain disease characterized by motor disturbances; however, the identification of several risk factors and the hypothesis that PD has a gastrointestinal onset have shed additional light. Today, after recognition of prodromal non-motor symptoms and the pathological processes driving their evolution, there is a greater understanding of the involvement of other organ systems. For this reason, PD is increasingly seen as a multiorgan and multisystemic pathology that arises from the interaction of susceptible genetic factors with a challenging environment during aging-related decline.
Subject(s)
Humans , Parkinson Disease/pathology , Gastrointestinal Tract , Risk Factors , Gastrointestinal Microbiome , Prodromal Symptoms , alpha-SynucleinABSTRACT
Parkinson's disease (PD) is the most common neurodegenerative movement disease. It is featured by abnormal alpha-synuclein (α-syn) aggregation in dopaminergic neurons in the substantia nigra. Macroautophagy (autophagy) is an evolutionarily conserved cellular process for degradation of cellular contents, including protein aggregates, to maintain cellular homeostasis. Corynoxine B (Cory B), a natural alkaloid isolated from Uncaria rhynchophylla (Miq.) Jacks., has been reported to promote the clearance of α-syn in cell models by inducing autophagy. However, the molecular mechanism by which Cory B induces autophagy is not known, and the α-syn-lowering activity of Cory B has not been verified in animal models. Here, we report that Cory B enhanced the activity of Beclin 1/VPS34 complex and increased autophagy by promoting the interaction between Beclin 1 and HMGB1/2. Depletion of HMGB1/2 impaired Cory B-induced autophagy. We showed for the first time that, similar to HMGB1, HMGB2 is also required for autophagy and depletion of HMGB2 decreased autophagy levels and phosphatidylinositol 3-kinase III activity both under basal and stimulated conditions. By applying cellular thermal shift assay, surface plasmon resonance, and molecular docking, we confirmed that Cory B directly binds to HMGB1/2 near the C106 site. Furthermore, in vivo studies with a wild-type α-syn transgenic drosophila model of PD and an A53T α-syn transgenic mouse model of PD, Cory B enhanced autophagy, promoted α-syn clearance and improved behavioral abnormalities. Taken together, the results of this study reveal that Cory B enhances phosphatidylinositol 3-kinase III activity/autophagy by binding to HMGB1/2 and that this enhancement is neuroprotective against PD.
ABSTRACT
GBA1 is one of the common risk genes of Parkinson′s disease (PD), which encodes glucocerebrosidase. It is difficult to distinguish PD patients with heterozygous variants of GBA1 ( GBA1-PD) from idiopathic Parkinson′s disease patients, but GBA1-PD tends to progress faster, be more severe, and be more likely to be associated with cognitive impairment and other non-motor symptoms. The pathological mechanism of the increased risk of PD in GBA1 heterozygous variant carriers may be related to autophagy-lysosome dysfunction and mitochondrial dysfunction. Targeted therapy for GBA1 is expected to become a new direction of precision therapy for PD. In this article, the epidemiology and clinical features of GBA1-PD, the possible pathogenesis of GBA1 variation, and the therapeutic strategies for GBA1-PD were elaborated.
ABSTRACT
Parkinson’s Disease (PD) is a progressive neurodegenerative disorder involving the loss of dopaminergic neurons. Despite the availability of many drugs to ease the life of PD patients, there is no permanent cure until now. Now-a-days, there has been a considerable attention towards the use of herbal products to treat PD patients worldwide due to less side effects. In this context, here we investigated myricetin, a common plant derived flavonoid, on the cognitive impairments exhibited by the transgenic Drosophila expressing human ?-synuclein in the neurons. The PD flies were allowed to feed on the diet having 10, 20 and 40 ?M of myricetin for 24 days and then assayed for cognitive impairments. The exposure of myricetin showed a dose dependent significant delay in the cognitive impairments. Molecular docking studies showed the positive interaction between myricetin and ?-synuclein. The results suggest a protective effect of myricetin against the cognitive impairments.
ABSTRACT
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.
ABSTRACT
Dementia with Lewy bodies(DLB)is the second most common neurodegenerative dementia after Alzheimer's Disease(AD). This article will mainly elaborate the relationship between DLB and blood-brain barrier(BBB)from the following five aspects: (1)The structure and function of BBB; (2)In vivo assessment methods for the blood-brain barrier damage; (3)Evidence for the damage of blood-brain barrier in DLB; (4)The relationship between α-synuclein and the blood-brain barrier; (5)The relationship between APOE and the blood-brain barrier.Future research should focus on the pathogenesis of BBB damage in DLB patients, by which new drug targets for disease diagnosis and treatment may be found.
ABSTRACT
Multiple system atrophy(MSA)is a rare and fatal neurodegenerative disease occurring in middle-aged and older people, mainly characterized by autonomic nervous system and motor dysfunction.At present, there is no effective method to prevent or reverse its progression, and its treatment is mostly symptom-based, with limited success.A large number of interventional trials have been conducted to explore new treatments for MSA, but there is no clearly effective disease-modifying therapy, probably as a result of poor understanding of the pathophysiological and physiological mechanisms underlying MSA, which may be influenced by multiple factors.The purpose of this paper is to review the existing intervention trials for disease modification therapy of MSA and to discuss the outlook for new therapeutic targets.
ABSTRACT
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.
ABSTRACT
The remodeling of phospholipid includes two processes: deacylation and reacylation. It realizes the conversion of nascent phospholipids to mature phospholipids by changing the length and types of fatty acids at specific sites of phospholipids, which is a key step in phospholipid metabolism. Phospholipids are not only the basic components of biological membranes, but also participate in the transduction of many molecular signals in cells. Therefore, phospholipid remodeling disorders can affect the structure and function of cell membranes, as well as the activity of membrane proteins, causing a series of intricate signaling cascades, and finally lead to many pathological changes including neurodegeneration. This paper reviews the basic process of phospholipid remodeling and the involvement of its key enzymes, calcium independent group VIA phospholipase A2 (iPLA2β), peroxiredoxin 6 (PRDX6), calcium independent group VIB phospholipase A2 (iPLA2γ) as well as acyl-CoA lysocardiolipin acyltransferase 1 (ALCAT1) in the pathology of Parkinson's disease. The mutations in the gene encoding iPLA2β, PLA2G6, have been widely reported to be directly related to hereditary Parkinson disease-14 (PARK14). Here we focus on the molecular mechanism of iPLA2β in the development of Parkinson's disease, mainly involving phospholipid fatty acid metabolism disorders, mitochondrial physiology abnormalities and α-synuclein aggregate formation and other aspects, which will help to understand the role of phospholipid remodeling in Parkinson's disease, and provide new clues for the development of new Parkinson's disease diagnosis and treatment strategies.
ABSTRACT
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.
ABSTRACT
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.
ABSTRACT
Objective:To investigate the effect of interfering S-phase kinase associated protein 1 (SKP1) gene on apoptosis in Parkinson's disease(PD) cell model induced by 1-methyl-4-phenyl-pyridine ion (MPP+ ) and the mechanism of ubiquitin proteasome system degradation of α-synuclein (α-syn) influence.Methods:SH-SY5Y cells were divided into control group, MPP+ group, SKP1 interference group, and SKP1 interference+ MG132(UPS inhibitor) group.The cells in the control group were cultured normally. The cells in the latter three groups were incubated with MPP+ (0.5 mmol/L) for 24 h as PD model cells.The cells in SKP1 interference group were transfected with lentivirus SKP1-siRNA, and the cells in SKP1 interference+ MG132 group were transfected with lentivirus SKP1 siRNA and added with MG132 (0.5 μmol/L) for 24 h. The protein levels and mRNA levels of SKP1, microtubule-associated protein light chain 3 (LC3), lysosome-associated membrane protein (LAMP), α-syn, ubiquitin activating enzyme E1 (UBE1), parkin, and p27 in cells were detected by Western blot and RT-PCR.Flow cytometry was used to detect cell apoptosis and cycle level, and CCK-8 method was used to detect cell proliferation level.Co-immunoprecipitation method was used to explore the interaction between SKP1 and p27. SPSS 23.0 software was used for statistical analysis. One-way ANOVA was used for comparison among groups, and LSD test was used for further pairwise comparison.Results:RT-PCR and Western blot results showed that the mRNA levels and protein levels of autophagy related proteins and ubiquitin related proteins LC3, LAMP2, α-syn, UBE1, parkin and p27 in the four groups were statistically significant(mRNA: F=99.155, 43.028, 138.464, 28.200, 22.009, 28.147, all P<0.05; F=245.517, 157.634, 315.920, 2 336.472, 477.429, 2 350.201, all P<0.05). The mRNA and protein levels of LC3, Lamp2, α-syn and p27 in SKP1 interference group were lower than those in MPP+ group (all P<0.05), while the mRNA and protein levels of UBE1 and parkin were higher than those in MPP+ group (all P<0.05). The mRNA and protein levels of LC3, α-syn and p27 in SKP1 interference+ MG132 group were higher than those in SKP1 interference group (all P<0.05), and the mRNA and protein levels of UBE1 and parkin were lower than those in SKP1 interference group (all P<0.05). The results of flow cytometry and CCK-8 method showed that the apoptosis rate and cell inhibition rate among the four groups were significantly different( F=2 749.420, 171.508, both P<0.05). The apoptosis rate of SKP1 interference group was lower than that of MPP+ group ((8.22±0.25)%, (15.30±0.21)%, P<0.05), while the cell inhibition rate of SKP1 interference group was lower than that of MPP+ group((26.31±3.73)%, (55.05±3.84)%, P<0.05). The apoptosis rate of SKP1 interference+ MG132 group ((9.49±0.07)%) was higher than that of SKP1 interference group, and the cell inhibition rate ((36.06±2.85)%) was higher than that of SKP1 interference group (both P<0.05). The results of immunoprecipitation method showed that P27 decreased after SKP1 immunoprecipitation. Conclusion:After SKP1 gene was interfered, the autophagy function of PD cells decreased, which may be related to parkin promoting α-syn ubiquitination, activating UBE1/ Parkin-mediated UPS pathway to degrade α-syn, and mediating P27 to inhibit apoptosis.
ABSTRACT
Objective:To investigate the relationship between plasma phosphorylated α-synuclein (ps129-α-syn) and cognitive function in Parkinson disease (PD).Methods:This study recruited 90 PD patients who were hospitalized in the Department of Neurology, Henan province people's hospital from March 2019 to June 2020.Forty healthy middle-aged and elderly people with normal cognitive function who came to the hospital for physical examination were selected during the same period.Clinical characteristics and blood samples were collected.Patients with PD were classified into those with normally cognitive (PD-NC), mild cognitive impairment (PD-MCI), and dementia (PDD). The enzyme-linked immunosorbent assay was used to measure the plasma ps129-α-syn.Correlations between plasma ps129-α-syn and clinical characteristics such as disease duration, Hoehn-Yahr stage (H-Y), unified Parkinson's disease rating scale (UPDRS), Montreal cognitive assessment (MoCA), 14-item Hamilton anxiety rating scale (HAMA-14), the 24-item Hamilton depression rating scale (HAMD-24), levodopa equivalent daily dosage (LEDD), the scale of outcomes in Parkinson's disease for autonomic symptoms, SCOPA-AUT) were analyzed using Pearson or Spearman correlation analysis.Multiple linear regression analysis was used to evaluate the factors affecting the cognitive function of PD.Results:Plasma ps129-α-syn in PD patients was higher than that in healthy controls((19.44±8.93)μg/L, (10.78±5.87)μg/L, ( t=5.615, P<0.01). Plasma ps129-α-syn was higher in PD-MCI group((19.64±7.77)μg/L)and PDD group((23.79±9.47)μg/L) compared with that in PD-NC group((13.37±5.40)μg/L)( P<0.05). Plasma ps129-α-syn was positively correlated with H-Y ( r=0.404, P<0.01), UPDRS-Ⅲ( r=0.275, P=0.009), UPDRS-total ( r=0.211, P=0.046) and SCOPA-AUT( r=0.335, P=0.001). Plasma ps129-α-syn was negatively associated with MoCA ( r=-0.459, P<0.01). Multiple linear regression analysis suggested disease duration ( t=-4.618, P<0.01), ps129-α-syn( t=-3.792, P<0.01) and UPDRS-total ( t=-2.826, P=0.006) were independently associated with cognitive function.Plasma ps129-α-syn could discriminate between PD-NC and PD cognitive function impairment with an AUC of 0.7797 (95% CI: 0.686 3-0.873 2, P<0.01). Conclusions:Plasma ps129-α-syn is correlated with cognitive function and the severity of motor symptoms in PD patients, and have high sensitivity and specificity in diagnosing PD cognitive dysfunction.Therefore, plasma ps129-α-syn can serve as a biomarker to assess cognitive function in PD.
ABSTRACT
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
Acupuncture can improve the motor and non-motor symptoms of Parkinson's disease, and the effect of acupuncture combined with drug therapy is better than that of drug therapy alone. The possible mechanism includes inhibiting α-synuclein aggregation, oxidative stress, and neuroinflammation, inhibiting the apoptosis of dopaminergic neurons, and achieving a neuroprotective effect. The points mainly selected for Acupuncture treatment for this disease are Zusanli (ST 36), Yanglingquan (GB 34), Taichong (LR 3), Xuehai (SP 10), and other points. Early use of acupuncture and acupuncture combined with medical treatment strategy is worthy of clinical application.
ABSTRACT
γ-synuclein (SNCG) has been extensively studied for its specific overexpression in various malignant neoplasms. Recently, SNCG has been found to be involved in multiple signaling pathways, including estrogen, AKT-mTOR, mitogen-activated protein kinase (MAPK) and microtubule regulation. SNCG has also been found to be related to the proliferation, invasion, migration and chemotherapy drug resistance of neoplasms. Therefore, SNCG is expected to be the key target of anti-tumor and improving the sensitivity of tumor cells to chemotherapeutic drugs.