ABSTRACT
The bile acid tauroursodeoxycholic acid (TUDCA) reduces cell death under oxidative stress and inflammation. Implants of bone marrow-derived stromal cells (bmSC) are currently under investigation in clinical trials of spinal cord injury (SCI). Since cell death of injected bmSC limits the efficacy of this treatment, the cytoprotective effect of TUDCA may enhance its benefit. We therefore studied the therapeutic effect of TUDCA and its use as a combinatorial treatment with human bmSC in a rat model of SCI. A spinal cord contusion injury was induced at thoracic level T9. Treatment consisted of i.p. injections of TUDCA alone or in combination with one injection of human bmSC into the cisterna magna. The recovery of motor functions was assessed during a surveillance period of six weeks. Biochemical and histological analysis of spinal cord tissue confirmed the anti-inflammatory activity of TUDCA. Treatment improved the recovery of autonomic bladder control and had a positive effect on motor functions in the subacute phase, however, benefits were only transient, such that no significant differences between vehicle and TUDCA-treated animals were observed 1-6 weeks after the lesion. Combinatorial treatment with TUDCA and bmSC failed to have an additional effect compared to treatment with bmSC only. Our data do not support the use of TUDCA as a treatment of SCI.
ABSTRACT
Genetic mutations in FUS, a DNA/RNA-binding protein, are associated with inherited forms of frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). A novel transgenic FUS[1-359]-tg mouse line recapitulates core hallmarks of human ALS in the spinal cord, including neuroinflammation and neurodegeneration, ensuing muscle atrophy and paralysis, as well as brain pathomorphological signs of FTLD. However, a question whether FUS[1-359]-tg mouse displays behavioural and brain pro-inflammatory changes characteristic for the FTLD syndrome was not addressed. Here, we studied emotional, social and cognitive behaviours, brain markers of inflammation and plasticity of pre-symptomatic FUS[1-359]-tg male mice, a potential FTLD model. These animals displayed aberrant behaviours and altered brain expression of inflammatory markers and related pathways that are reminiscent to the FTLD-like syndrome. FTLD-related behavioural and molecular Journal of Cellular and Molecular Medicine features were studied in the pre-symptomatic FUS[1-359]-tg mice that received standard or new ALS treatments, which have been reported to counteract the ALS-like syndrome in the mutants. We used anti-ALS drug riluzole (8 mg/kg/d), or anti-inflammatory drug, a selective blocker of cyclooxygenase-2 (celecoxib, 30 mg/kg/d) for 3 weeks, or a single intracerebroventricular (i.c.v.) infusion of human stem cells (Neuro-Cells, 500 000-CD34+ ), which showed anti-inflammatory properties. Signs of elevated anxiety, depressive-like behaviour, cognitive deficits and abnormal social behaviour were less marked in FUS-tg-treated animals. Applied treatments have normalized protein expression of interleukin-1ß (IL-1ß) in the prefrontal cortex and the hippocampus, and of Iba-1 and GSK-3ß in the hippocampus. Thus, the pre-symptomatic FUS[1-359]-tg mice demonstrate FTLD-like abnormalities that are attenuated by standard and new ALS treatments, including Neuro-Cell preparation.
Subject(s)
Anti-Inflammatory Agents/pharmacology , Brain/drug effects , Frontotemporal Lobar Degeneration/drug therapy , Frontotemporal Lobar Degeneration/metabolism , RNA-Binding Protein FUS/metabolism , Amyotrophic Lateral Sclerosis/drug therapy , Amyotrophic Lateral Sclerosis/metabolism , Animals , Behavior, Animal/drug effects , Brain/metabolism , Cyclooxygenase 2/metabolism , Glycogen Synthase Kinase 3 beta/metabolism , Inflammation/drug therapy , Inflammation/metabolism , Interleukin-1beta/metabolism , Male , Mice , Mutation/drug effects , Neurons/drug effects , Neurons/metabolism , Social Behavior , Spinal Cord/drug effects , Spinal Cord/metabolismABSTRACT
BACKGROUND: Spinal cord injury (SCI) is a highly debilitating pathology without curative treatment. One of the most promising disease modifying strategies consists in the implantation of stem cells to reduce inflammation and promote neural regeneration. In the present study we tested a new human bone marrow-derived stromal cell preparation (bmSC) as a therapy of SCI. METHODS: Spinal cord contusion injury was induced in adult male rats at thoracic level T9/T10 using the Infinite Horizon impactor. One hour after lesion the animals were treated with a sub-occipital injection of human bmSC into the cisterna magna. No immune suppression was used. One dose of bmSC consisted, on average, of 2.3 million non-manipulated cells in 100 µL suspension, which was processed out of fresh human bone marrow from the iliac crest of healthy volunteers. Treatment efficacy was compared with intraperitoneal injections of methylprednisolone (MP) and saline. The recovery of motor functions was assessed during a surveillance period of nine weeks. Adverse events as well as general health, weight and urodynamic functions were monitored daily. After this time, the animals were perfused, and the spinal cord tissue was investigated histologically. RESULTS: Rats treated with bmSC did not reject the human implants and showed no sign of sickness behavior or neuropathic pain. Compared to MP treatment, animals displayed better recovery of their SCI-induced motor deficits. There were no significant differences in the recovery of bladder control between groups. Histological analysis at ten weeks after SCI revealed no differences in tissue sparing and astrogliosis, however, bmSC treatment was accompanied with reduced axonal degeneration in the dorsal ascending fiber tracts, lower Iba1-immunoreactivity (IR) close to the lesion site and reduced apoptosis in the ventral grey matter. Neuroinflammation, as evidenced by CD68-IR, was significantly reduced in the MP-treated group. CONCLUSIONS: Human bmSC that were prepared by negative selection without expansion in culture have neuroprotective properties after SCI. Given the effect size on motor function, implantation in the acute phase was not sufficient to induce spinal cord repair. Due to their immune modulatory properties, allogeneic implants of bmSC can be used in combinatorial therapies of SCI.
Subject(s)
Inflammation/prevention & control , Injections, Intraperitoneal , Injections, Spinal , Mesenchymal Stem Cell Transplantation/instrumentation , Nerve Regeneration/physiology , Spinal Cord Injuries/therapy , Humans , Mesenchymal Stem Cells/physiologyABSTRACT
AIMS: Mutations in DNA/RNA-binding factor (fused-in-sarcoma) FUS and superoxide dismutase-1 (SOD-1) cause amyotrophic lateral sclerosis (ALS). They were reproduced in SOD-1-G93A (SOD-1) and new FUS[1-359]-transgenic (FUS-tg) mice, where inflammation contributes to disease progression. The effects of standard disease therapy and anti-inflammatory treatments were investigated using these mutants. METHODS: FUS-tg mice or controls received either vehicle, or standard ALS treatment riluzole (8 mg/kg/day), or anti-inflammatory drug a selective blocker of cyclooxygenase-2 celecoxib (30 mg/kg/day) for six weeks, or a single intracerebroventricular (i.c.v.) infusion of Neuro-Cells (a preparation of 1.39 × 106 mesenchymal and hemopoietic human stem cells, containing 5 × 105 of CD34+ cells), which showed anti-inflammatory properties. SOD-1 mice received i.c.v.-administration of Neuro-Cells or vehicle. RESULTS: All FUS-tg-treated animals displayed less marked reductions in weight gain, food/water intake, and motor deficits than FUS-tg-vehicle-treated mice. Neuro-Cell-treated mutants had reduced muscle atrophy and lumbar motor neuron degeneration. This group but not celecoxib-FUS-tg-treated mice had ameliorated motor performance and lumbar expression of microglial activation marker, ionized calcium-binding adapter molecule-1 (Iba-1), and glycogen-synthase-kinase-3ß (GSK-3ß). The Neuro-Cells-treated-SOD-1 mice showed better motor functions than vehicle-treated-SOD-1 group. CONCLUSION: The neuropathology in FUS-tg mice is sensitive to standard ALS treatments and Neuro-Cells infusion. The latter improves motor outcomes in two ALS models possibly by suppressing microglial activation.
Subject(s)
Amyotrophic Lateral Sclerosis/therapy , Anti-Inflammatory Agents/administration & dosage , Hematopoietic Stem Cell Transplantation/methods , Inflammation Mediators/antagonists & inhibitors , Motor Skills Disorders/therapy , Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/metabolism , Animals , Cells, Cultured , Inflammation Mediators/metabolism , Injections, Intraventricular/methods , Male , Mice , Mice, Transgenic , Motor Neurons/metabolism , Motor Neurons/pathology , Motor Skills Disorders/genetics , Motor Skills Disorders/metabolism , Superoxide Dismutase/genetics , Superoxide Dismutase/metabolism , Treatment OutcomeABSTRACT
Parkinson's disease is a devastating, progressive neurodegenerative disorder that affects the central and peripheral nervous systems. Although recent advancements have led to a better understanding of the disorder, there is currently no long-term disease-modifying strategy. Recently, preclinical data have identified the significant effects of pluripotent stem cell grafting in 6-OHDA and MPTP animal models of motor parkinsonism; there have also been some clinical data in patients with motor parkinsonism. Pluripotent stem cells can nestle in affected organs and can differentiate into a variety of cells, including neural (dopamine producing) cells. Depending on the environment into which they are grafted, these stem cells can also influence immune responses by regulating the activity of B-cells, T-cells, and NK-cells. Pluripotent stem cells can also produce chemotrophins, including BDNF (brain-derived neurotrophic factor), GDNF (glial-derived neurotrophic factor), NGF (nerve growth factor), TGF-ß (transforming growth factor-ß), IGF-1 (insulin-like growth factor 1), NT-3 (neurotrophin 3), and SCF-1 (stem cell factor 1). Influencing these trophic factors can influence plasticity. This article explores the potential of pluripotent stem cells in the treatment of PD. We will explore the utilization of pluripotent stem cells in the immunomodulation of B-cells, T-cells and NK-cells, the transdifferentiation of pluripotent stems cells into DA-cells, and the secretion of trophic factors and its relation to plasticity. We will also cover how best to conduct a clinical trial, which stem cells can be safely used in patients, what are the methods of induction before application, and how to re-apply stem cells in patients by intravasal, intrathecal or intracerebral methods. Finally, we will describe how to objectively record the clinical results.
Subject(s)
Parkinsonian Disorders/surgery , Stem Cell Transplantation/methods , Stem Cells/physiology , Animals , HumansABSTRACT
Parkinson's disease (PD) is a synucleinopathy-induced chronic progressive neurodegenerative disorder, worldwide affecting about 5 million humans. As of yet, actual therapies are symptomatic, and neuroprotective strategies are an unmet need. Due to their capability to transdifferentiate, to immune modulate and to increase neuroplasticity by producing neurotrophic factors, adult stem cells (ASC) might fill this gap. Preclinical research in 6-hydroxydopamine (6-OHDA) and/or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) lesioned animals established persistent improvements of motor behavior after ASC-treatment. Histological/histochemical measurements in these animals evidenced an intracerebral applied ASC-induced increase of Tyrosine Hydroxylase-positive (TH+) cells with increased striatal dopamine levels, suggesting cell rescue. Likewise, clinical experience with subventricular applied ASCs in PD patients, although limited, is encouraging, evidencing neurorescue especially during the early phase of the disease. In multiple system atrophy (MSA) or progressive supranuclear palsy (PSP) patients, though, only marginal reduced progression of natural progression could be established after subventricular or intravasal ASC implantations.
ABSTRACT
Ischemic and traumatic insults of the central nervous system both result in definite chronic disability, only to some extent responsive to rehabilitation. Recently, the application of autologous stem cells (fresh bone marrow-derived mononuclear cells including mesenchymal and hematopoietic stem cells) was suggested to provide a strategy to further improve neurological recovery in these disorders. During the acute phase, stem cells act mainly by neuroprotection with prevention of apoptosis, whereas during the chronic situation they provide neurorestoration by transdifferentiation and/or the secretion of neurotrophic factors. To reach these goals, in the acute phase, stem cells (10 million mononuclear cells per kg body weight) might be best applied intravenously, as during the first 7 days after the lesion, the blood-brain barrier permits passage of cells from the blood into the brain or the spinal cord. In the more chronic situation, though, those cells might be applied best intrathecally by lumbar puncture. Based on the reported results so far, it seems justified to develop well-designed clinical double-blind trials in chronic spinal cord injury and ischemic stroke patients, as efficacy and safety concerns might not be answered by preclinical studies.
Subject(s)
Adult Stem Cells/physiology , Central Nervous System Diseases/surgery , Stem Cell Transplantation/methods , Central Nervous System Diseases/etiology , Humans , Ischemia/complications , Transplantation, AutologousABSTRACT
Objective Olfactory dysfunction is an early and common symptom in Parkinson disease (PD). Previously, the authors demonstrated that idiopathic olfactory dysfunction in first-degree relatives of PD patients is associated with an increased risk of developing PD within 2 years. The aim of the present study was to determine the value of combined olfactory testing and SPECT scanning in predicting future PD in the same population of relatives over a 5-year period. Methods In a cohort of 361 non-parkinsonian, non-demented first-degree relatives of PD patients, a combination of olfactory processing tasks was used to select groups of hyposmic (n=40) and normosmic (n=38) individuals for a 5-year clinical follow-up evaluation and sequential SPECT scanning, using a dopamine transporter ligand to assess nigrostriatal dopaminergic function at baseline and 5 years from baseline. A validated questionnaire, sensitive to the presence of parkinsonism, was used in the follow-up of the remaining 283 relatives. Results Five years from baseline, five out of the 40 hyposmic relatives fulfilled clinical diagnostic criteria for PD. None of the other 349 relatives available for follow-up developed PD. All hyposmic individuals developing PD had an abnormal baseline SPECT scan. Discussion In conclusion, idiopathic hyposmia in first-degree relatives of PD patients is associated with an increased risk of developing clinical PD of 12.5% over a 5-year period. The present data suggest that a two-step approach using olfactory testing followed by SPECT scanning in hyposmic individuals has a very high sensitivity and specificity in detecting PD. The usefulness of this two-step approach needs to be confirmed in larger populations.
Subject(s)
Dopamine Plasma Membrane Transport Proteins/metabolism , Olfaction Disorders/diagnosis , Olfaction Disorders/etiology , Parkinson Disease , Aged , Brain/metabolism , Brain/physiopathology , Corpus Striatum/metabolism , Female , Functional Laterality/physiology , Humans , Male , Middle Aged , Parkinson Disease/complications , Parkinson Disease/metabolism , Parkinson Disease/physiopathology , Severity of Illness Index , Substantia Nigra/metabolism , Surveys and Questionnaires , Tomography, Emission-Computed, Single-PhotonABSTRACT
In this paper, we tentatively bring together the psychiatric, neurological and addiction perspectives on the impulsive-compulsive spectrum of neuropsychiatric disorders, in order to understand the pathophysiology of impulse control disorders (ICDs) in Parkinson's disease. In an attempt to try to pool the various levels of information we will therefore focus on three disorders within the impulse-compulsive spectrum, i.e., obsessive-compulsive disorder (OCD), ICDs in Parkinson's disease, and cocaine seeking behaviour. Whereas there are large differences between these three domains, each with their own nomenclature, hypotheses and study results, they share the focus on an imbalance within and between the frontal-striatal circuits as underlying substrate for the behaviours. For each disorder, we summarize the results from recent studies in order to describe in which way alterations in the frontal-striatal circuits contribute to the phenotype. The phenomenological overlap between ICDs in Parkinson's disease, addiction and OCD needs further investigation, since better understanding of the overlapping and differentiating characteristics will contribute to our understanding of the pathophysiology of the disturbances and treatment alternatives.
Subject(s)
Compulsive Behavior/pathology , Corpus Striatum/pathology , Frontal Lobe/pathology , Cocaine-Related Disorders/pathology , Humans , Models, Biological , Neural Pathways/pathology , Parkinson Disease/complicationsABSTRACT
Olfactory deficits and executive dysfunction are early and common symptoms in Parkinson's disease (PD). Previous studies have shown that hyposmia can be a first sign of PD. The aim of the present study was to determine which of three olfactory tests and two selected tests of executive function would be the best predictor of future PD over a 5 year period. In a cohort of 361 nonparkinsonian, nondemented first-degree relatives of PD patients, in whom alternative causes of olfactory dysfunction were excluded, we measured baseline performance on three olfactory and two executive function tasks. Five years from baseline, clinical neurological evaluation and/or a screening questionnaire, sensitive to the presence of Parkinsonism, were used to detect individuals developing clinical PD. Our results show that in first degree relatives of PD patients worse performance on each of three olfactory processing tasks was associated with an increased risk of developing PD within 5 years, whereas performance on selected tests of executive dysfunction was not associated with an increased risk of developing PD. Interestingly, impaired odor discrimination was the best predictor for future PD.
Subject(s)
Cognition Disorders/etiology , Olfaction Disorders/complications , Parkinson Disease/diagnosis , Parkinson Disease/etiology , Problem Solving/physiology , Aged , Family Health , Female , Humans , Longitudinal Studies , Male , Middle Aged , Neurologic Examination , Neuropsychological Tests , Predictive Value of Tests , Regression AnalysisABSTRACT
Clinical symptoms in Parkinson's disease (PD) comprise both motor and non-motor symptoms. In this disease, synucleinopathic-induced, nigral dopamine deficiency-related dysfunction of the basal ganglia is held responsible for the characteristic levodopa-responsive motor signs and symptoms (bradykinesia, hypokinesia, rigidity), known as parkinsonism and essential for clinical diagnosis in PD, as well as subtle motivational and cognitive dysfunctions. Some motor symptoms, such as tremor and postural instability, and most non-motor symptoms, however, are not fully levodopa-responsive, and suggested to manifest extranigral pathology. These symptoms include autonomic, sleep, sensory and neuropsychiatric symptoms, which in some cases may precede the first signs of motor parkinsonism, closely correlating with the progression of Lewy body pathology in PD. The recognition and treatment of these mostly under-recognized and under-treated symptoms is important, as these symptoms might have more impact on the quality of life in PD patients as compared to motor parkinsonism. On top of this, recognition of these manifestations in the prodromal phase of motor PD is critical to early diagnosis and treatment, as disease-modifying drugs, once identified, should be initiated as soon as possible, preferably in this premotor phase of the disease. On top of this, (non)motor extranigral symptoms in PD might also be of iatrogenic origin, whether directly as indirectly. During conventional, oral, dopaminomimetic treatment, the progressive loss of striatal dopaminergic nerve endings with the loss of cerebral dopamine storage capacity, renders the cerebral dopamine level fully dependent of the plasma levodopa levels, thus changing dopaminergic receptor stimulation from continuous to a more pulsatile pattern. Supposedly due to this process, neuroplastic changes in (sub)cortical dopaminergic pathways might cause therapeutic response fluctuations: motor and nonmotor fluctuations with anxiety- and panic-attacks and/or mood swings, dyskinesias and punding. Finally, dopaminomimetic pharmacotherapy may also induce extranigral non-motor drug-related direct adverse effects, such as impulse control disorders. In this article, non-motor signs and symptoms of extranigral PD-related pathology will be discussed, as well as the (suggested) criteria for diagnosis and treatment. Of course, also the recognition of the signs and symptoms of the prodromal (premotor) phase, suggestive for the presence of the PD, will be discussed. Iatrogenic non-motor symptoms, though, will not be further discussed.
Subject(s)
Autonomic Nervous System Diseases/etiology , Behavioral Symptoms/etiology , Parkinson Disease/complications , Sensation Disorders/etiology , Sleep Wake Disorders/etiology , HumansABSTRACT
The aim of this study was to determine whether extended olfactory testing within a single olfactory task and/or across olfactory tasks increases diagnostic accuracy of olfactory testing in Parkinson's disease (PD). Olfactory function was assessed using an extended version of the "Sniffin' Sticks", comprising 32-item odor identification and discrimination tasks, and a detection threshold task in 52 PD patients and 50 controls, all aged between 49 and 78 years. ROC curves based on sensitivity and specificity estimates were used to compare the diagnostic accuracy of extended and combined olfactory testing. There was no significant difference in diagnostic accuracy between the 16-item and the 32-item versions of the odor identification or discrimination test. The single olfactory test that was best in discriminating between PD patients and controls was a 16-item odor identification test. A combination of the 16-item identification test and the detection threshold task had a significantly higher area under the curve than the 16-item odor identification test alone. In conclusion, extended testing across, and not within, olfactory tasks increases diagnostic accuracy of olfactory testing in PD. A combination of an odor detection threshold task and a 16-item odor identification test had the highest sensitivity and specificity in distinguishing between PD patients and controls.
Subject(s)
Neuropsychological Tests , Olfaction Disorders/diagnosis , Parkinson Disease/physiopathology , Aged , Discrimination, Psychological , Female , Humans , Male , Middle Aged , Odorants , Olfaction Disorders/etiology , Parkinson Disease/complications , ROC Curve , Recognition, Psychology , Sensitivity and Specificity , Sensory ThresholdsABSTRACT
Recent studies have demonstrated increased resting-state cortico-cortical functional connectivity in untreated Parkinson's disease (PD). We set out to determine whether this connectivity can be modulated by dopamine replacement therapy (DRT) and explore the relationship of therapy-induced changes in connectivity with motor improvement in the relatively early stages of DRT in PD. Whole-head magnetoencephalography was performed in an eyes-closed resting-state condition in 37 patients with levodopa-treated PD (Hoehn and Yahr stages 1-3) both in a practically defined "OFF" and in the "ON" medication state. Data analysis involved calculation of three synchronisation likelihood (SL; a general measure of linear and non-linear temporal correlations between time series) measures which reflect functional coupling within and between ten major cortical areas in five frequency bands. The transition from the "OFF" to the "ON" state led to increases of SL in the 4-30 Hz range, most conspicuously with regard to local SL, in tandem with motor improvement. We found a negative correlation between the change in local beta SL and the reduction of parkinsonism after DRT. Patients presenting with relatively large motor responses (41% or better) actually showed decreases in local beta SL. The present study shows that the already elevated levels of resting-state cortico-cortical functional connectivity in the 4-30 Hz range in mild to moderate PD are on average increased even further by DRT. However, a strong motor response appears to be associated with decreases in local beta-band coupling, which may constitute a risk factor for the development of motor response fluctuations or dyskinesias.
Subject(s)
Cerebral Cortex/metabolism , Dopamine/metabolism , Nerve Net/metabolism , Neural Pathways/metabolism , Parkinson Disease/metabolism , Aged , Cerebral Cortex/drug effects , Cerebral Cortex/physiopathology , Dopamine Agents/pharmacology , Evoked Potentials/drug effects , Female , Humans , Levodopa/pharmacology , Magnetoencephalography , Male , Middle Aged , Movement/drug effects , Nerve Net/drug effects , Nerve Net/physiopathology , Neural Pathways/drug effects , Neural Pathways/physiopathology , Parkinson Disease/drug therapy , Parkinson Disease/physiopathology , Synaptic Transmission/drug effectsABSTRACT
The aim of the present study was to evaluate complex upper limb motor function in newly diagnosed, untreated Parkinson's disease (PD) patients. Four different unimanual upper limb motor tasks were applied to 13 newly diagnosed, untreated PD patients and 13 age- and sex-matched controls. In a handwriting task, PD patients had significantly reduced sentence length and writing velocity, and decreasing letter height in the course of writing. Furthermore, PD patients performed an aiming task slower with than without target, and showed increased transposition in a pointing task. The results of this study extend previous observations of impaired complex upper limb movements to newly diagnosed, untreated PD patients.
Subject(s)
Motor Skills Disorders/etiology , Parkinson Disease/complications , Parkinson Disease/pathology , Upper Extremity/physiopathology , Adult , Aged , Analysis of Variance , Case-Control Studies , Female , Handwriting , Humans , Male , Middle Aged , Psychomotor Performance/physiology , Task Performance and AnalysisABSTRACT
Parkinsonism is a clinical syndrome characterized by bradykinesia, hypo-/akinesia, muscular rigidity, and resting tremor, mainly caused by Parkinson's disease (PD). Symptoms of PD are due to a progressive loss of nigral neurons causing striatal dopaminergic denervation. However, nigral degeneration is only a part of the underlying synucleinopathy, and clinical symptoms go far beyond motor parkinsonism. Olfactory disturbances, fatigue, pain, autonomic dysfunction, sleep fragmentation, depression, and dementia with or without psychosis are frequently seen. The variability in the expression of these signs and symptoms, as discussed in this paper, might be explained by the specific topographical sequence of the pathology, depending on the extent and progression of the degenerative process at defined sites. Better insight in the clinicopathological correlations of this disease may help to further develop early diagnosis and adequate therapeutic strategies.
Subject(s)
Parkinson Disease/pathology , Autonomic Nervous System Diseases/complications , Cognition Disorders/psychology , Humans , Mood Disorders/psychology , Muscle Fatigue/physiology , Olfaction Disorders/etiology , Pain/etiology , Parkinson Disease/complications , Parkinson Disease/physiopathology , Sleep Wake Disorders/psychologyABSTRACT
Patients receiving oral levodopa, the standard treatment for Parkinson's disease (PD), eventually develop motor fluctuations and dyskinesias. Treatment options for patients with these symptoms include high-frequency deep brain stimulation of the subthalamic nucleus (STN-DBS) or continuous dopaminergic stimulation (CDS). STN-DBS is the prevalent surgical therapy for PD and has shown efficacy, but behavioural disorders, including cognitive problems, depression and suicidality have been reported. CDS can be achieved with oral dopamine agonists with a long half-life, transdermal or subcutaneous delivery of dopamine agonists, or intestinal levodopa infusion. Of these, duodenal levodopa infusion appears to be the most promising option in terms of both efficacy and safety.
Subject(s)
Deep Brain Stimulation/methods , Dopamine Agonists/administration & dosage , Parkinson Disease/therapy , Dopamine Agonists/adverse effects , Humans , Parkinson Disease/metabolismABSTRACT
BACKGROUND: One of the perceptual abnormalities observed in Parkinson's disease (PD) is a deficit in the suppression of reflexive saccades that are automatically triggered by the onset of a peripheral target. Impairment of substantia nigra function is thought to lead to this reduced ability to suppress reflexive saccades. METHODS: The present study examined whether this perceptual deficit is also present in early stage PD when using hardly noticeable task-irrelevant stimuli. Eleven non-demented de novo, untreated PD patients (mean age 57 yr, range 44-70) participated in the study as well as 12 age-matched controls. Performance on an 'oculomotor capture' task, in which in half of the trials an irrelevant stimulus with sudden onset was added to the display, was compared between patients and controls. Analysis of variance (ANOVA) was performed with group (patients/controls) and age (< 61 yrs/> or = 61 yrs) as independent factors and type of trial (control/distracter) as repeated measurements factor. The factor sex was used as covariate. RESULTS: With respect to Reaction Time (RT), a significant interaction between group and condition was found. RTs increased under the 'irrelevant stimulus' condition in both groups, the patients exhibiting a significantly larger increase in RTs than the control group. Also, a significant interaction effect between group and condition for number of correct responses was found. The number of correct responses was reduced in the onset distracter condition, the reduction being larger in the patients. In the patient group, contrary to the control group, a higher age was associated with fewer correct responses at baseline and in the onset distracter condition, suggesting that perceptual functions in PD are highly susceptible to the effects of ageing. The increased reaction times and larger number of incorrect responses of the PD patients in the onset distracter condition may be related to impairments of substantia nigra function and lower brain stem. CONCLUSION: The capture task seems to be a sensitive instrument to detect early perceptual deficits in PD. The magnitude of the observed deficits suggests that perceptual functions in early stage PD are so substantially impaired that this may interfere with daily activities.
Subject(s)
Attention , Fixation, Ocular , Intention , Parkinson Disease/physiopathology , Saccades , Visual Perception , Adult , Aged , Female , Humans , Male , Middle Aged , Reaction TimeABSTRACT
Bimanual coordination involves the simultaneous performance of either symmetrical (in-phase) or asymmetrical (anti-phase) movements with both hands and is known to be impaired in Parkinson's disease (PD). At present, it is unclear whether this aspect of motor function is already impaired in early stage, untreated PD patients. Therefore, we investigated the accuracy of bimanual coordination in 13 early stage, untreated PD patients and 13 age- and sex-matched healthy controls. Each subject performed bimanual coordination tasks at two different movement frequencies (1 and 1.75 Hz) and with two different phase relationships (in-phase and anti-phase). The percentage of unsuccessful trials (as a measure of overall task performance) in PD patients was significantly higher than in healthy subjects. PD patients performed high frequency in-phase and anti-phase bimanual coordination tasks less accurately with their non-dominant hand than healthy subjects. Furthermore, PD patients had more difficulty than healthy subjects in maintaining a constant phase relationship between the hands in the anti-phase condition at low movement frequency. This study demonstrates that bimanual coordination dysfunction is a very early sign of PD. Bimanual coordination tasks, in particular those involving high frequency anti-phase movements, might prove useful in the early diagnosis of PD.