The aim of the present study was to reveal the role of cortical-striatum postsynaptic dopamine D2 receptor (D2R) in improving motor behavioral dysfunction in Parkinson's disease (PD) mice by exercise. C57/BL6 male adult mice were randomly divided into control, PD and PD plus exercise groups. The mice were injected with 6-OHDA in striatum to establish a unilateral injury PD model. The exercise intervention program was uniform speed running (16 m/min, 40 min/d, 5 d per week for 4 weeks). Autonomic activity of mice was tested by open field test. Cortical-striatum synaptic transmission efficiency was assessed by peak amplitude of field excitatory postsynaptic potential (fEPSP) recorded from in vitro brain slides. Meanwhile, the effects of D2R agonist on autonomic activity and cortical-striatal synaptic transmission were observed. The results showed that, compared with PD group, PD plus exercise group exhibited significantly increased autonomic motor distance and proportion of fast-moving (P < 0.05), as well as decreased maximum amplitude of fEPSP under increasing stimulation intensity (0.75-3.00 pA) (P < 0.05) and slope of stimulus-response curve. Compared with PD mice without D2R agonist, the movement distance and rapid movement ratio of PD mice treated with D2R agonist were increased significantly (P < 0.05), whereas fEPSP peak amplitude (P < 0.05) and the slope of stimulus-response curve were decreased. These results indicate that either early exercise intervention or D2R agonist treatment can inhibit the abnormal increase of cortical-striatum synaptic transmission and improve the autonomic motor ability in PD mice, suggesting that the cortical-striatum synaptic D2R may be an important molecular target for exercise to improve the autonomic motor ability of PD mice.
Animals ; Corpus Striatum ; physiology ; Male ; Mice ; Mice, Inbred C57BL ; Oxidopamine ; Parkinson Disease ; physiopathology ; therapy ; Physical Conditioning, Animal ; Random Allocation ; Receptors, Dopamine D2 ; agonists ; physiology ; Synaptic Transmission

ObjectiveExcessive daytime sleepiness (EDS) is one of the most common sleep abnormalities in patients with Parkinson's disease (PD), yet its multifactorial etiology complicates its treatment. This review summarized recent studies on the epidemiology, etiology, clinical implications, associated features, and evaluation of EDS in PD. The efficacy of pharmacologic and non-pharmacologic treatments for EDS in PD was also reviewed.

Data SourcesEnglish language articles indexed in PubMed and Cochrane databases and Chinese-language papers indexed in Wanfang and National Knowledge Infrastructure databases that were published between January 1987 and November 2017 were located using the following search terms: "sleepiness", "sleep and Parkinson's disease", and "Parkinson's disease and treatment".

Study SelectionOriginal research articles and critical reviews related to EDS in PD were selected.

ResultsEDS is a major health hazard and is associated with many motor and nonmotor symptoms of PD. Its causes are multifactorial. There are few specific guidelines for the treatment of EDS in PD. It is first necessary to identify and treat any possible factors causing EDS. Recent studies showed that some nonpharmacologic (i.e., cognitive behavioral therapy, light therapy, and repetitive transcranial magnetic stimulation) and pharmacologic (i.e., modafinil, methylphenidate, caffeine, istradefylline, sodium oxybate, and atomoxetine) treatments may be effective in treating EDS in PD.

ConclusionsEDS is common in the PD population and can have an immensely negative impact on quality of life. Its causes are multifactorial, which complicates its treatment. Further investigations are required to determine the safety and efficacy of potential therapies and to develop novel treatment approaches for EDS in PD.

Female ; Humans ; Male ; Parkinson Disease ; physiopathology ; Quality of Life ; Sleep Wake Disorders ; physiopathology

ObjectiveRapid eye movement sleep behavior disorder (RBD) is characterized by dream enactment and loss of muscle atonia during rapid eye movement sleep. RBD is closely related to α-synucleinopathies including Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. Many studies have investigated the markers of imaging and neurophysiological, genetic, cognitive, autonomic function of RBD and their predictive value for neurodegenerative diseases. This report reviewed the progress of these studies and discussed their limitations and future research directions.

Data SourcesUsing the combined keywords: "RBD", "neurodegenerative disease", "Parkinson disease", and "magnetic resonance imaging", the PubMed/MEDLINE literature search was conducted up to January 1, 2018.

Study SelectionA total of 150 published articles were initially identified citations. Of the 150 articles, 92 articles were selected after further detailed review. This study referred to all the important English literature in full.

ResultsSingle-nucleotide polymorphisms in SCARB2 (rs6812193) and MAPT (rs12185268) were significantly associated with RBD. The olfactory loss, autonomic dysfunction, marked electroencephalogram slowing during both wakefulness and rapid eye movement sleep, and cognitive impairments were potential predictive markers for RBD conversion to neurodegenerative diseases. Traditional structural imaging studies reported relatively inconsistent results, whereas reduced functional connectivity between the left putamen and substantia nigra and dopamine transporter uptake demonstrated by functional imaging techniques were relatively consistent findings.

ConclusionsMore longitudinal studies should be conducted to evaluate the predictive value of biomarkers of RBD. Moreover, because the glucose and dopamine metabolisms are not specific for assessing cognitive cognition, the molecular metabolism directly related to cognition should be investigated. There is a need for more treatment trials to determine the effectiveness of interventions of RBD on preventing the conversion to neurodegenerative diseases.

Biomarkers ; blood ; Humans ; Lysosome-Associated Membrane Glycoproteins ; genetics ; Neurodegenerative Diseases ; blood ; genetics ; physiopathology ; Parkinson Disease ; blood ; genetics ; physiopathology ; Polymorphism, Single Nucleotide ; genetics ; REM Sleep Behavior Disorder ; blood ; genetics ; physiopathology ; Receptors, Scavenger ; genetics ; tau Proteins ; genetics

BackgroundSleep disturbance is one of the major non-motor symptoms which cause the disability of Parkinson's disease (PD) patients. Cystatin C (CysC) is a more sensitive biomarker than serum creatinine or estimated glomerular filtration rate. Previous studies have reported altered CysC levels in neurodegenerative disorders and sleep disorders. This study aimed to explore the correlations of serum CysC levels and objective sleep disturbances in early PD.

MethodsWe recruited 106 early PD patients and 146 age- and sex-matched controls. All participants underwent clinical investigation and video-polysomnography. Sleep parameters and serum levels of CysC were measured. Then, we investigated the relationships between CysC and clinical variables and objective sleep disturbances in early PD patients.

ResultsThe mean serum level of CysC was significantly higher in patients with early PD (1.03 ± 0.19 mg/L) compared to controls (0.96 ± 0.15 mg/L, P = 0.009). There were significantly positive correlations between serum CysC levels and age (r = 0.334, P < 0.001), gender (r = 0.264, P = 0.013), and creatinine levels (r = 0.302, P = 0.018) in early PD patients. Increased serum CysC levels in early PD patients were significantly associated with higher apnea and hypopnea index (AHI) (r = 0.231, P = 0.017), especially hypopnea index (r = 0.333, P < 0.001). In early PD patients, elevated serum CysC levels were positively correlated with oxygen desaturation index (r = 0.223, P = 0.021), percentage of time spent at oxygen saturation (SaO) <90% (r = 0.644, P < 0.001), arousal with respiratory event during sleep (r = 0.247, P = 0.013). On the contrary, the elevated serum CysC levels were negatively correlated with mean and minimal SaO(r = -0.323, -0.315, both P = 0.001) in PD patients.

ConclusionsThe level of serum CysC was higher in early PD patients. PD patients with elevated serum CysC levels had more respiratory events and more severe oxygen desaturation. Therefore, the serum CysC levels may predict the severities of sleep-disordered breathing problems in early PD patients.

Aged ; Cystatin C ; blood ; Female ; Glomerular Filtration Rate ; physiology ; Humans ; Male ; Middle Aged ; Parkinson Disease ; blood ; physiopathology ; Polysomnography ; Sleep Wake Disorders ; blood ; physiopathology

BackgroundRapid eye movement (REM) sleep behavior disorder (RBD) and obstructive sleep apnea (OSA) are the most common sleep disorders in Parkinson's disease (PD). The aim of this study was to identify whether RBD could alleviate OSA severity in PD patients and its effect on cognitive impairment.

MethodsFrom February 2014 to May 2017, we recruited 174 PD patients from the Second Affiliated Hospital of Soochow University, all of whom underwent polysomnography (PSG). We collected clinical data, PSG results, and compared information between patients with and without RBD or OSA by analysis of covariance. We also investigated the effect of these sleep disorders on cognitive impairment using linear regression.

ResultsWe grouped participants as follows: PD only (n = 53), PD + OSA (n = 29), PD + RBD (n = 61), and PD + RBD + OSA (n = 31). Minimum oxygen saturation (SaO) during whole sleep and in REM sleep was higher in PD + RBD + OSA patients than that in PD + OSA patients. PD + RBD patients had worse Mini-Mental Status Examination and Montreal Cognitive Assessment (MoCA) scores than those in the PD group (P < 0.001), especially in visuospatial/executive, attention, and memory functions. The PD + OSA group performed worse than the PD group in the delayed recall domain. After adjusting for age, sex, body mass index, education, disease severity, and other sleep disorders, MoCA was negatively associated with OSA (β = -0.736, P = 0.043) and RBD (β = -2.575,P < 0.001). The severity of RBD (tonic/phasic electromyography activity) and OSA (apnea-hypopnea index/oxygen desaturation index/minimum SaO) were also associated with MoCA. The adjusted β values of RBD-related parameters were higher than that for OSA.

ConclusionsWe found that RBD alleviated OSA severity; however, RBD and OSA together exacerbated PD cognitive impairment. Further studies are needed to evaluate whether OSA treatment can improve cognition in PD.

Aged ; Female ; Humans ; Linear Models ; Male ; Middle Aged ; Parkinson Disease ; pathology ; physiopathology ; Polysomnography ; REM Sleep Behavior Disorder ; pathology ; physiopathology ; Sleep Apnea, Obstructive ; pathology ; physiopathology ; Sleep, REM ; physiology

To investigate the effect of Parkinson's disease related protein DJ-1 on the cell proliferation, apoptosis, invasion and migration in human osteosarcoma cells and the underlying molecular mechanisms. 
 Methods: The protein expression levels of DJ-1 were detected in human osteosarcoma cell lines (MG-63, Saos-2, and U2OS) and human osteoblast cell line hFOB1.19 with or without deficiency in phosphatase and tensin homolog deleted from chromosome 10 (PTEN) were detected by Western blot. Osteosarcoma cells were treated with DJ-1 siRNA, and then the protein expression levels of DJ-1 were detected by Western blot. Cell survival rate of osteosarcoma cells was detected by cell counting kit-8 (CCK-8) assay. Cell apoptosis of osteosarcoma cells was measured by annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) double staining method. Cell invasive and migration ability of osteosarcoma cells were examined by transwell invasion and migration assay. 
 Results: Compared with that of human osteoblast cell line (hFOB1.19), the protein expression level of DJ-1 was significantly upregulated in human osteosarcoma cell lines (MG-63, Saos-2, and U2OS) (all P<0.05), and U2OS had the highest level of DJ-1 when compared with the other three cell lines (P<0.01). DJ-1 siRNA could significantly down-regulate the DJ-1 protein expression in U2OS cells, and also diminish the cell survival rate. Moreover, DJ-1 down-regulation of DJ-1 could promote cell apoptosis, suppress the ability of cell invasion and migration, and increase the PTEN protein expression level (all P<0.05). In addition, the protein expression level of PTEN was markedly up-regulated in human osteosarcoma cell lines when compared with that in the hFOB1.19 cells (P<0.05). 
 Conclusion: DJ-1 can promote the cell proliferation, inhibit cell apoptosis, and decrease the ability of cell invasion and migration, and the potential underlying mechanisms may be associated with the up-regulation of PTEN protein expression.
Apoptosis ; genetics ; Cell Line, Tumor ; Cell Movement ; genetics ; Cell Proliferation ; genetics ; Gene Expression Regulation, Neoplastic ; Humans ; Neoplasm Invasiveness ; genetics ; PTEN Phosphohydrolase ; genetics ; Parkinson Disease ; physiopathology ; Protein Deglycase DJ-1 ; genetics ; metabolism ; RNA, Small Interfering ; genetics

Animals ; Behavior, Animal ; physiology ; Dopamine ; metabolism ; Dopaminergic Neurons ; physiology ; Humans ; Mice ; Motor Activity ; physiology ; Parkinson Disease ; metabolism ; physiopathology ; Pars Compacta ; physiopathology

Previous studies have shown that electroacupuncture (EA) promotes recovery of motor function in Parkinson's disease (PD). However the mechanisms are not completely understood. Clinically, the subthalamic nucleus (STN) is a critical target for deep brain stimulation treatment of PD, and vesicular glutamate transporter 1 (VGluT1) plays an important role in the modulation of glutamate in the STN derived from the cortex. In this study, a 6-hydroxydopamine (6-OHDA)-lesioned rat model of PD was treated with 100 Hz EA for 4 weeks. Immunohistochemical analysis of tyrosine hydroxylase (TH) showed that EA treatment had no effect on TH expression in the ipsilateral striatum or substantia nigra pars compacta, though it alleviated several of the parkinsonian motor symptoms. Compared with the hemi-parkinsonian rats without EA treatment, the 100 Hz EA treatment significantly decreased apomorphine-induced rotation and increased the latency in the Rotarod test. Notably, the EA treatment reversed the 6-OHDA-induced down-regulation of VGluT1 in the STN. The results demonstrated that EA alleviated motor symptoms and up-regulated VGluT1 in the ipsilateral STN of hemi-parkinsonian rats, suggesting that up-regulation of VGluT1 in the STN may be related to the effects of EA on parkinsonian motor symptoms via restoration of function in the cortico-STN pathway.
Adrenergic Agents ; toxicity ; Animals ; Apomorphine ; pharmacology ; Disease Models, Animal ; Dopamine Agonists ; pharmacology ; Electroacupuncture ; methods ; Functional Laterality ; drug effects ; Male ; Medial Forebrain Bundle ; injuries ; Motor Activity ; drug effects ; physiology ; Neurons ; drug effects ; metabolism ; Oxidopamine ; toxicity ; Parkinson Disease, Secondary ; chemically induced ; physiopathology ; therapy ; Rats ; Rats, Sprague-Dawley ; Subthalamic Nucleus ; drug effects ; metabolism ; pathology ; Tyrosine 3-Monooxygenase ; metabolism ; Up-Regulation ; drug effects ; physiology ; Vesicular Glutamate Transport Protein 1 ; metabolism

BACKGROUNDBoth Parkinson's disease (PD) and multiple system atrophy (MSA) have associated sleep disorders related to the underlying neurodegenerative pathology. Clinically, MSA with predominant parkinsonism (MSA-P) resembles PD in the manifestation of prominent parkinsonism. Whether the amount of rapid eye movement (REM) sleep without atonia could be a potential marker for differentiating MSA-P from PD has not been thoroughly investigated. This study aimed to examine whether sleep parameters could provide a method for differentiating MSA-P from PD.

METHODSThis study comprised 24 MSA-P patients and 30 PD patients, and they were of similar age, gender, and REM sleep behavior disorder (RBD) prevalence. All patients underwent clinical evaluation and one night of video-polysomnography recording. The tonic and phasic chin electromyogram (EMG) activity was manually quantified during REM sleep of each patient. We divided both groups in terms of whether they had RBD to make subgroup analysis.

RESULTSNo significant difference between MSA-P group and PD group had been found in clinical characteristics and sleep architecture. However, MSA-P patients had higher apnea-hypopnea index (AHI; 1.15 [0.00, 8.73]/h vs. 0.00 [0.00, 0.55]/h, P = 0.024) and higher tonic chin EMG density (34.02 [18.48, 57.18]% vs. 8.40 [3.11, 13.06]%, P < 0.001) as compared to PD patients. Subgroup analysis found that tonic EMG density in MSA + RBD subgroup was higher than that in PD + RBD subgroup (55.04 [26.81, 69.62]% vs. 11.40 [8.51, 20.41]%, P < 0.001). Furthermore, no evidence of any difference in tonic EMG density emerged between PD + RBD and MSA - RBD subgroups (P > 0.05). Both disease duration (P = 0.056) and AHI (P = 0.051) showed no significant differences during subgroup analysis although there was a trend toward longer disease duration in PD + RBD subgroup and higher AHI in MSA - RBD subgroup. Stepwise multiple linear regression analysis identified the presence of MSA-P (β = 0.552, P < 0.001) and RBD (β = 0.433, P < 0.001) as predictors of higher tonic EMG density.

CONCLUSIONTonic chin EMG density could be a potential marker for differentiating MSA-P from PD.

Aged ; Body Mass Index ; Electromyography ; methods ; Female ; Humans ; Male ; Middle Aged ; Multiple System Atrophy ; diagnosis ; physiopathology ; Parkinson Disease ; physiopathology ; Parkinsonian Disorders ; physiopathology ; Polysomnography ; Retrospective Studies

The dysfunction of subthalamic nucleus is the main cause of Parkinson's disease. Local field potentials in human subthalamic nucleus contain rich physiological information. The present study aimed to quantify the oscillatory and dynamic characteristics of local field potentials of subthalamic nucleus, and their modulation by the medication therapy for Parkinson's disease. The subthalamic nucleus local field potentials were recorded from patients with Parkinson's disease at the states of on and off medication. The oscillatory features were characterised with the power spectral analysis. Furthermore, the dynamic features were characterised with time-frequency analysis and the coefficient of variation measure of the time-variant power at each frequency. There was a dominant peak at low beta-band with medication off. The medication significantly suppressed the low beta component and increased the theta component. The amplitude fluctuation of neural oscillations was measured by the coefficient of variation. The coefficient of variation in 4-7 Hz and 60-66 Hz was increased by medication. These effects proved that medication had significant modulation to subthalamic nucleus neural oscillatory synchronization and dynamic features. The subthalamic nucleus neural activities tend towards stable state under medication. The findings would provide quantitative biomarkers for studying the mechanisms of Parkinson's disease and clinical treatments of medication or deep brain stimulation.
Antiparkinson Agents ; therapeutic use ; Beta Rhythm ; Electrodes ; Evoked Potentials ; Humans ; Oscillometry ; Parkinson Disease ; drug therapy ; physiopathology ; Subthalamic Nucleus ; physiopathology ; Theta Rhythm