ABSTRACT
AIMS: Synaptic dysfunction in Parkinson's disease is caused by propagation of pathogenic α-synuclein between neurons. Previously, in multiple system atrophy (MSA), pathologically characterised by ectopic deposition of abnormal α-synuclein predominantly in oligodendrocytes, we demonstrated that the occurrence of memory impairment was associated with the number of α-synuclein-positive neuronal cytoplasmic inclusions (NCIs) in the hippocampus. In the present study, we aimed to investigate how abnormal α-synuclein in the hippocampus can lead to memory impairment. METHODS: We performed pathological and biochemical analyses using a mouse model of adult-onset MSA and human cases (MSA, N = 25; Parkinson's disease, N = 3; Alzheimer's disease, N = 2; normal controls, N = 11). In addition, the MSA model mice were examined behaviourally and physiologically. RESULTS: In the MSA model, inducible human α-synuclein was first expressed in oligodendrocytes and subsequently accumulated in the cytoplasm of excitatory hippocampal neurons (NCI-like structures) and their presynaptic nerve terminals with the development of memory impairment. α-Synuclein oligomers increased simultaneously in the hippocampus of the MSA model. Hippocampal dendritic spines also decreased in number, followed by suppression of long-term potentiation. Consistent with these findings obtained in the MSA model, post-mortem analysis of human MSA brain tissues showed that cases of MSA with memory impairment developed more NCIs in excitatory hippocampal neurons along with α-synuclein oligomers than those without. CONCLUSIONS: Our results provide new insights into the role of α-synuclein oligomers as a possible pathological cause of memory impairment in MSA.
Subject(s)
Multiple System Atrophy , Parkinson Disease , Humans , Multiple System Atrophy/pathology , alpha-Synuclein/metabolism , Parkinson Disease/pathology , Inclusion Bodies/pathology , Neurons/pathology , Brain/pathologyABSTRACT
We report the case of a Japanese woman with sporadic amyotrophic lateral sclerosis (ALS) of 28 months' duration who died at the age of 66 years. Postmortem examination revealed moderate loss of neurons and phosphorylated TDP-43 (p-TDP-43)-immunoreactive neuronal and glial cytoplasmic inclusions in the upper and lower motor neurons. Additionally, marked neuronal loss was observed in the neostriatum, globus pallidum, subthalamic nucleus, and substantia nigra. p-TDP-43-immunoreactive inclusions were frequently found in these areas. Neuronal loss and TDP-43 pathology in the motor, striatonigral, and pallidoluysian systems were predominant on the right side. Moreover, p-TDP-43-immunoreactive cat's-eye-shaped neuronal nuclear inclusions (NNIs) were observed in the affected lesions. NNIs in the striatonigral system were also positive for valosin-containing protein (VCP). We diagnosed the patient as having ALS with striatonigral and pallidoluysian degeneration. Patients with ALS rarely experience pallido-nigro-luysian degeneration. To our best knowledge, only one case of ALS combined with striatonigral and pallidoluysian degeneration has been reported. Neuronal loss in the striatonigral and/or pallidoluysian systems has also been reported in patients with ALS with multisystem degeneration accompanied by long-term use of an artificial respirator. Based on these findings, a possibility of an extremely rare subtype of ALS demonstrating selective loss of neurons in the striatonigral and pallidoluysian systems exists; another possibility is that this type could be an early stage or forme fruste of ALS with multisystem degeneration. Although VCP-positive cat's-eye-shaped NNIs have been reported in spinocerebellar ataxia type-2 cases, our case report presents VCP-positive NNIs in a patient with ALS for the first time.
Subject(s)
Amyotrophic Lateral Sclerosis , Amyotrophic Lateral Sclerosis/pathology , Autopsy , DNA-Binding Proteins/metabolism , Humans , Intranuclear Inclusion Bodies/metabolism , Motor Neurons/pathologyABSTRACT
Levo-dihydroxyphenylalanine (L-DOPA) is the most effective treatment for Parkinson's disease; however, most patients develop uncontrollable abnormal involuntary movements known as L-DOPA-induced dyskinesia. L-DOPA-induced dyskinesia can be reduced by pallidotomy of the medial globus pallidus or pallidal deep brain stimulation, suggesting that the medial globus pallidus plays a significant role in the development of L-DOPA-induced dyskinesia. In the present study, the pathological changes of the medial globus pallidus in L-DOPA-induced dyskinesia were studied in rat models of Parkinson's disease (unilateral 6-hydroxydopamine lesioning) and L-DOPA-induced dyskinesia (L-DOPA injection in Parkinson's disease-model rats twice daily for 2 weeks, confirmed by display of dyskinesia-like abnormal involuntary movements). L-DOPA-induced dyskinesia-model rats displayed medial globus pallidus hypertrophy, enlarged axon terminals surrounding the dendrites of medial globus pallidus neurons, and increased density of synaptic vesicles in enlarged axon terminals on the lesioned side. Synaptic terminal enlargement reversed after discontinuation of L-DOPA. Histological studies revealed the enlarged synaptic terminals were those of GABAergic striatal (direct pathway) neurons. A single injection of L-DOPA enhanced GABA release in the medial globus pallidus on the lesioned side in L-DOPA-induced dyskinesia-model rats compared to Parkinson's disease-model rats. In addition, microinjection of muscimol, a GABAA receptor agonist, into the medial globus pallidus on the lesioned side of Parkinson's disease-model rats induced dyskinesia-like abnormal involuntary movements. Microinjection of bicuculline, a GABAA receptor antagonist, into the medial globus pallidus on the lesioned side alleviated L-DOPA-induced dyskinesia in Parkinson's disease-model rats that had received L-DOPA prior to the microinjection. These results indicate that priming for L-DOPA-induced dyskinesia comprises excessive GABA storage in axon terminals of the direct pathway and that expression of L-DOPA-induced dyskinesia is associated with enhanced GABA release into the medial globus pallidus after L-DOPA dosing and the resultant excessive stimulation of GABAA receptors.
Subject(s)
Antiparkinson Agents/toxicity , Dyskinesia, Drug-Induced/metabolism , Globus Pallidus/metabolism , Levodopa/toxicity , Parkinsonian Disorders/metabolism , gamma-Aminobutyric Acid/metabolism , Animals , Globus Pallidus/drug effects , Male , Neuronal Plasticity/drug effects , Neurons/drug effects , Neurons/metabolism , Rats , Rats, Wistar , Synaptic Transmission/drug effectsABSTRACT
OBJECTIVES: Non-motor symptoms (NMSs) negatively impact the health-related quality of life (HrQOL) of patients with Parkinson's disease (PD). The Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) is a comprehensive scale for evaluating PD. It remains unclear whether the NMSs evaluated with MDS-UPDRS are predictive of HrQOL. This study aimed to investigate whether NMSs, as evaluated with the MDS-UPDRS, could predict the HrQOL of patients with PD. MATERIALS AND METHODS: We conducted a 2-year retrospective observational cohort study assessing 108 patients with PD who were recruited from a single tertiary center between January 2015 and December 2017. MDS-UPDRS was used to assess NMSs and motor symptoms and Parkinson's Disease Questionnaire-39 (PDQ-39) to measure patients' HrQOL. RESULTS: The median age of patients was 69 years, and 65.7% were female. The median MDS-UPDRS part I, part II, part III, and PDQ-39-summary index scores were 8, 10, 22, and 25, respectively. The final stepwise multiple linear regression model showed that female sex (standard partial regression coefficient ß = 0.131, P < 0.05) and baseline MDS-UPDRS part I (ß = 0.272, P < 0.01) and part II (ß = 0.571, P < 0.01) scores significantly predicted the PDQ-39-SI scores at the 2-year follow-up. CONCLUSIONS: In addition to motor symptoms, NMSs at the 2-year follow-up may be useful for predicting the HrQOL of patients with PD. In clinical practice, MDS-UPDRS-guided assessment and treatment of motor symptoms and NMSs may contribute to improving HrQOL in patients with PD.
Subject(s)
Parkinson Disease , Quality of Life , Aged , Female , Humans , Male , Parkinson Disease/diagnosis , Retrospective Studies , Severity of Illness Index , Surveys and QuestionnairesABSTRACT
A 51-year-old Japanese woman was admitted to our hospital because of speech difficulty following severe headache. Neurological examination showed dysarthria and tongue weakness on the right side, indicating right hypoglossal nerve palsy. Needle electromyography of the right side of the tongue showed fibrillation potentials. Magnetic resonance angiography and computed tomography angiography revealed a right, persistent, primitive hypoglossal artery (PPHA) that met Lie's diagnostic criteria. Digital subtraction angiography showed an extended PPHA with irregular caliber in the portion running through the right hypoglossal canal. We diagnosed compression neuropathy of the hypoglossal nerve due to PPHA enlargement based on the findings of ipsilateral hypoglossal nerve palsy, fibrillation that indicated peripheral nerve palsy, and the enlarged diameter of the portion of the PPHA running through the right hypoglossal canal. We prescribed antihypertensive therapy. At 1 year after onset, her tongue weakness was alleviated. Clinicians should consider compression neuropathy due to a PPHA as one of the possibilities in the differential diagnosis of hypoglossal nerve palsy.
Subject(s)
Arteries/abnormalities , Hypoglossal Nerve Diseases/etiology , Hypoglossal Nerve/physiopathology , Nerve Compression Syndromes/etiology , Tongue/blood supply , Tongue/innervation , Vascular Malformations/complications , Antihypertensive Agents/therapeutic use , Arteries/diagnostic imaging , Arteries/physiopathology , Female , Humans , Hypoglossal Nerve Diseases/diagnosis , Hypoglossal Nerve Diseases/physiopathology , Middle Aged , Nerve Compression Syndromes/diagnosis , Nerve Compression Syndromes/physiopathology , Recovery of Function , Treatment Outcome , Vascular Malformations/diagnostic imaging , Vascular Malformations/drug therapy , Vascular Malformations/physiopathologyABSTRACT
OBJECTIVES: Physician-staffed helicopter transport is faster than ground transport and allows for prompt medical care of patients in rural areas. In this study, we evaluated the relationship between helicopter transport and the prognosis of patients with acute cerebral infarction in rural Japan. METHODS: This retrospective, observational study included 546 patients with acute cerebral infarction attending Aomori Prefectural Central Hospital, which serves a rural region of Japan. Patients were separated into 2 transport groups: physician-staffed helicopter emergency medical services and ground emergency medical services. Patients were assessed for stroke severity, treatment, and prognosis. RESULTS: Of the 546 patients, 11.2% were transported by physician-staffed helicopter emergency medical services and 88.8% by ground emergency medical services. Although the distance transported was significantly longer in the physician-staffed helicopter emergency medical services group, the time from onset to reaching our hospital was similar between the groups. National Institutes of Health Stroke Scale on admission and final prognosis were significantly worse with physician-staffed helicopter emergency medical services than with ground emergency medical services. Multivariate analysis showed no association between transport system and prognosis. CONCLUSIONS: In this study, patients transported by physician-staffed helicopter emergency medical services had more severe stroke symptoms and poorer functional outcomes than those transported by ground emergency medical services. However, the transport time was shorter for physician-staffed helicopter emergency medical services; thus, physician-staffed helicopter emergency medical services may be useful for reducing transport time for patients in rural Japan.
Subject(s)
Air Ambulances , Cerebral Infarction/therapy , Rural Health Services , Time-to-Treatment , Aged , Aged, 80 and over , Cerebral Infarction/diagnosis , Cerebral Infarction/physiopathology , Disability Evaluation , Female , Health Status , Humans , Japan , Male , Recovery of Function , Retrospective Studies , Severity of Illness Index , Time Factors , Treatment OutcomeABSTRACT
Parkinson's disease (PD) is a neurodegenerative disorder associated with the progressive loss of nigrostriatal dopaminergic neurons. Levodopa is the most effective treatment for the motor symptoms of PD. However, chronic oral levodopa treatment can lead to various motor and nonmotor complications because of nonphysiological pulsatile dopaminergic stimulation in the brain. Examinations of autopsy cases with PD have revealed a decreased number of dendritic spines of striatal neurons. Animal models of PD have revealed altered density and morphology of dendritic spines of neurons in various brain regions after dopaminergic denervation or dopaminergic denervation plus levodopa treatment, indicating altered synaptic transmission. Recent studies using rodent models have reported dendritic spine head enlargement in the caudate-putamen, nucleus accumbens, primary motor cortex, and prefrontal cortex in cases where chronic levodopa treatment following dopaminergic denervation induced dyskinesia-like abnormal involuntary movement. Hypertrophy of spines results from insertion of alpha-amino-2,3-dihydro-5-methyl-3-oxo-4-isoxazolepropanoic acid receptors into the postsynaptic membrane. Such spine enlargement indicates hypersensitivity of the synapse to excitatory inputs and is compatible with a lack of depotentiation, which is an electrophysiological hallmark of levodopa-induced dyskinesia found in the corticostriatal synapses of dyskinetic animals and the motor cortex of dyskinetic PD patients. This synaptic plasticity may be one of the mechanisms underlying the priming of levodopa-induced complications such as levodopa-induced dyskinesia and dopamine dysregulation syndrome. Drugs that could potentially prevent spine enlargement, such as calcium channel blockers, N-methyl-D-aspartate receptor antagonists, alpha-amino-2,3-dihydro-5-methyl-3-oxo-4-isoxazolepropanoic acid receptor antagonists, and metabotropic glutamate receptor antagonists, are candidates for treatment of levodopa-induced complications in PD. © 2017 International Parkinson and Movement Disorder Society.
Subject(s)
Antiparkinson Agents/adverse effects , Dendritic Spines/pathology , Dopaminergic Neurons/pathology , Levodopa/adverse effects , Parkinson Disease/drug therapy , Parkinson Disease/pathology , Animals , Caudate Nucleus/pathology , Dendritic Spines/drug effects , Dopaminergic Neurons/drug effects , Dyskinesia, Drug-Induced/etiology , Dyskinesia, Drug-Induced/pathology , Humans , Putamen/pathologyABSTRACT
BACKGROUND: Hyperthermia in patients with acute ischemic stroke is associated with poor outcome. Although previous studies have shown a negative effect on functional outcome, even in patients treated with intravenous recombinant tissue plasminogen activator (rt-PA), the effect on survival remains unclear. AIMS OF THE STUDY: The aim of this study was to evaluate the association between the functional and survival prognosis and hyperthermia in patients with acute ischemic stroke treated with rt-PA. METHODS: We studied 120 patients treated with rt-PA from 2306 consecutive Japanese patients with acute cerebral infarction at Aomori Prefectural Central Hospital between December 2009 and March 2017. We defined hyperthermia as ≥38°C within 72 hours after rt-PA administration. Propensity score matching was used to compare 34 non-hyperthermia and hyperthermia patient pairs. RESULTS: Final modified Rankin Scale scores were higher in the hyperthermia group than in the non-hyperthermia group. In addition, the Kaplan-Meier model showed that the non-hyperthermia group had significantly better survival rates than the hyperthermia group (hazard ratio, 5.3; 95% confidence intervals, 1.2-24.8). CONCLUSIONS: Hyperthermia within 3 days after rt-PA is associated with poor functional prognosis and survival outcome in patients with acute cerebral infarction.
Subject(s)
Fever/etiology , Fibrinolytic Agents/therapeutic use , Stroke/complications , Stroke/drug therapy , Tissue Plasminogen Activator/therapeutic use , Aged , Brain Ischemia/complications , Brain Ischemia/drug therapy , Brain Ischemia/mortality , Female , Fever/mortality , Humans , Male , Middle Aged , Proportional Hazards Models , Risk Factors , Stroke/mortality , Treatment OutcomeABSTRACT
A 31-year-old Japanese woman presented with sudden-onset unstable gait followed by nuchal pain. A neurological examination revealed right-sided limb weakness and decreased pain and thermal sensation on the left side below the level of the L1 dermatome. A lower lateral medullary infarction with ipsilateral hemiplegia, known as Opalski syndrome, caused by spontaneous vertebral artery dissection was diagnosed by magnetic resonance imaging. The spinothalamic tract in the medulla oblongata has a topographic arrangement of sensory fibers, and the dermatomal sensory deficit in this case can be explained in relation to that. This is the first reported case of Opalski syndrome with dermatomal sensory manifestations. Opalski syndrome could be a differential diagnosis for dermatomal sensory manifestations.
Subject(s)
Lateral Medullary Syndrome/complications , Somatosensory Disorders/etiology , Adult , Female , Humans , Lateral Medullary Syndrome/diagnostic imaging , Magnetic Resonance Angiography , Medulla Oblongata , Neurologic Examination , Skin/physiopathology , Somatosensory Disorders/diagnostic imaging , Vertebral Artery/diagnostic imagingABSTRACT
INTRODUCTION: The loss of epidermal nerve fibers is regarded as an early pathological change in human diabetes. We investigated epidermal Aδ nerve fiber function by examining pain threshold by means of intraepidermal electrical stimulation (IES) in early diabetic neuropathy. METHODS: We recruited 20 asymptomatic diabetic patients. Eighteen age-matched, healthy subjects served as controls. We placed the IES electrode onto the skin of the foot dorsum and delivered weak electrical stimulation. We defined pain threshold as the minimum electrical intensity at which a subject felt a pricking sensation. RESULTS: The mean pain thresholds in the patient group were significantly higher (0.053 ± 0.036 mA; P < 0.01) than in the control group (0.027 ± 0.006 mA). CONCLUSION: We confirmed that the pain threshold was elevated in early diabetic neuropathy. We conclude that the IES electrode is a useful tool to evaluate early diabetic polyneuropathy. Muscle Nerve 54: 146-149, 2016.
Subject(s)
Diabetic Neuropathies/physiopathology , Electric Stimulation , Epidermis/innervation , Nerve Fibers/physiology , Pain Threshold/physiology , Aged , Case-Control Studies , Female , Humans , Male , Middle AgedABSTRACT
Administering intravenous recombinant tissue plasminogen activator (r-tPA) within 4.5 h or endovascular procedures within 8 h of ischemic stroke onset may reduce the risk of disability. The effectiveness of media campaigns to raise stroke awareness and shorten pre-hospital delay is unclear. We studied 1144 consecutive ischemic stroke patients at Aomori Prefectural Central Hospital, Japan, between March 2010 and February 2014. From March 2012, the government sponsored an educational campaign based on a television commercial to improve knowledge of stroke symptoms and encourage ambulance calls for facial palsy, arm palsy, or speech disturbance. For the 544 and 600 patients admitted before and during the intervention, respectively, we recorded the National Institutes of Health Stroke Scale score, stroke type, the time when patients or bystanders recognized stroke symptoms, and hospital arrival time. Pre-hospital delay, as the time interval from awareness of stroke to hospital arrival, was categorized as 0-3, 3-6, and 6+ h. The mean pre-hospital delay was shorter (12.0 vs 13.5 h; P = 0.0067), the proportion of patients arriving within 3 h was larger (55.7 vs 46.5 %; P = 0.0021), and the proportion arriving after 6 h was smaller (32.7 vs 39.5 %; P = 0.0162) in the intervention group than in the pre-intervention group. There was no significant difference in the proportion of patients treated with r-tPA (6 and 7.5 % of the intervention and pre-intervention groups, respectively). A television-based public education campaign potentially reduced pre-hospital delay for ischemic stroke patients, but the r-tPA treatment rate was unchanged.
Subject(s)
Brain Ischemia/therapy , Health Education/methods , Hospitalization/statistics & numerical data , Stroke/therapy , Television , Time-to-Treatment/statistics & numerical data , Aged , Brain Ischemia/epidemiology , Female , Fibrinolytic Agents/therapeutic use , Health Knowledge, Attitudes, Practice , Humans , Japan/epidemiology , Male , Prospective Studies , Severity of Illness Index , Stroke/epidemiology , Time Factors , Tissue Plasminogen Activator/therapeutic useABSTRACT
Levodopa-induced dyskinesia (LID) is a major complication of long-term dopamine replacement therapy for Parkinson's disease, and becomes increasingly problematic in the advanced stage of the disease. Although the cause of LID still remains unclear, there is accumulating evidence from animal experiments that it results from maladaptive plasticity, resulting in supersensitive excitatory transmission at corticostriatal synapses. Recent work using transcranial magnetic stimulation suggests that the motor cortex displays the same supersensitivity in Parkinson's disease patients with LID. To date, the cellular mechanisms underlying the abnormal cortical plasticity have not been examined. The morphology of the dendritic spines has a strong relationship to synaptic plasticity. Therefore, we explored the spine morphology of pyramidal neurons in the motor cortex in a rat model of LID. We used control rats, 6-hydroxydopamine-lesioned rats (a model of Parkinson's disease), 6-hydroxydopamine-lesioned rats chronically treated with levodopa (a model of LID), and control rats chronically treated with levodopa. Because the direct pathway of the basal ganglia plays a central role in the development of LID, we quantified the density and size of dendritic spines in intratelencephalic (IT)-type pyramidal neurons in M1 cortex that project to the striatal medium spiny neurons in the direct pathway. The spine density was not different among the four groups. In contrast, spine size became enlarged in the Parkinson's disease and LID rat models. The enlargement was significantly greater in the LID model than in the Parkinson's disease model. This enlargement of the spines suggests that IT-type pyramidal neurons acquire supersensitivity to excitatory stimuli. To confirm this possibility, we monitored miniature excitatory postsynaptic currents (mEPSCs) in the IT-type pyramidal neurons in M1 cortex using whole-cell patch clamp. The amplitude of the mEPSCs was significantly increased in the LID model compared with the control. This indicates that the IT-type pyramidal neurons become hyperexcited in the LID model, paralleling the enlargement of spines. Thus, spine enlargement and the resultant hyperexcitability of IT-type pyramidal neurons in M1 cortex might contribute to the abnormal cortical neuronal plasticity in LID.
Subject(s)
Antiparkinson Agents/adverse effects , Dyskinesia, Drug-Induced/pathology , Levodopa/adverse effects , Motor Cortex/pathology , Parkinsonian Disorders/pathology , Pyramidal Cells/pathology , Animals , Antiparkinson Agents/pharmacology , Dendritic Spines/pathology , Dendritic Spines/physiology , Dyskinesia, Drug-Induced/physiopathology , Excitatory Postsynaptic Potentials , Levodopa/pharmacology , Male , Motor Cortex/drug effects , Motor Cortex/physiopathology , Neural Pathways/drug effects , Neural Pathways/pathology , Neural Pathways/physiopathology , Oxidopamine , Parkinsonian Disorders/drug therapy , Parkinsonian Disorders/physiopathology , Pyramidal Cells/drug effects , Pyramidal Cells/physiopathology , Rats , Rats, Wistar , Telencephalon/drug effects , Telencephalon/pathology , Telencephalon/physiopathologyABSTRACT
Maladaptive plasticity at corticostriatal synapses plays an important role in the development of levodopa-induced dyskinesia. Recently, it has been shown that synaptic plasticity is closely linked to morphologic changes of dendritic spines. To evaluate morphologic changes of dendritic spines of two types of striatal medium spiny neurons, which project to the internal segment of globus pallidus or the external segment of globus pallidus, in the levodopa-induced dyskinesia model, we used 6-hydroxydopamine-lesioned rats chronically treated with levodopa. Dendritic spines were decreased and became enlarged in the direct pathway neurons of the model of levodopa-induced dyskinesia. The same levodopa treatment to normal rats, in which no dyskinesia was observed, also induced enlargement of dendritic spines, but not a decrease in density of spines in the direct pathway neurons. These results suggest that a loss and enlargement of dendritic spines in the direct pathway neurons plays important roles in the development of levodopa-induced dyskinesia.
Subject(s)
Corpus Striatum/pathology , Dendritic Spines/pathology , Dyskinesia, Drug-Induced/pathology , Levodopa/pharmacology , Neostriatum/pathology , Neurites/drug effects , Animals , Disease Models, Animal , Male , Neurites/metabolism , Neurons/pathology , Parkinson Disease/pathology , Rats, Wistar , Synapses/drug effects , Synapses/pathologyABSTRACT
Atypical antipsychotics are considered to be better tolerated than typical antipsychotics; however, the risk of drug-induced movement disorders needs to be considered. Aripiprazole, a dopamine partial agonist, is one of the most frequently used atypical antipsychotics in children. In this report, we describe withdrawal dyskinesia after aripiprazole discontinuation in a child with autism spectrum disorder. The patient presented with oral dyskinesia after discontinuation of aripiprazole when he was 13 years old. Dyskinetic movements disappeared after reinitiation of aripiprazole. He developed oral dyskinesia again after a reduction of the aripiprazole dose when he was 14 years old. Dyskinesia gradually disappeared within a few months. Withdrawal dyskinesia associated with aripiprazole has been rarely reported in children. Moreover, there is no large study on the prevalence of dyskinesia associated with aripiprazole discontinuation either in adults or in children. However, relevant cases might be unreported, pretermitted, or regarded as akathisia or symptoms of attention-deficit hyperactivity disorder. The prevalence of withdrawal dyskinesia associated with aripiprazole, especially in children, may be more frequent than thought. Withdrawal dyskinesia is self-limited; however, such dyskinetic movements in children potentially result in irreversible effects that damage the quality of life. As such, physicians should be mindful when changing, reducing, or discontinuing antipsychotics in children.
ABSTRACT
Rare autosomal recessive variants in DJ-1, a causative gene for early-onset Parkinson's disease, have been associated with a variety of clinical syndromes in a limited number of patients. Here, we report a case of a novel DJ-1 variant in a 39-year-old man with a 4-year history of parkinsonism, cognitive dysfunction, and lower limb spasticity. He was diagnosed with Parkinson's disease. Genetic testing of the patient revealed compound heterozygous variants in the DJ-1 gene (exon 6 deletion + c.242dup), of which exon 6 deletion was a novel variant. We conclude that variants in DJ-1 should be considered possible causes of early-onset parkinsonism with spasticity and cognitive impairment, as in this case.
ABSTRACT
Levodopa-induced dyskinesia has been suggested to result from maladaptive plasticity at corticostriatal synapses. Synaptic plasticity is based upon morphologic changes of dendritic spines. To elucidate whether the morphologic changes of spines occur in the striatum of rat models of levodopa-induced dyskinesia, we examined immunoreactivity of drebrin, an actin-binding protein localized in dendritic spines of excitatory synapses, using 6-hydroxydopamine-lesioned rats repeatedly treated with levodopa. The cross-sectional area of drebrin-immunoreactive organelles, putative spines, in the dopamine-denervated striatum of the levodopa-induced dyskinesia model was greater than that of the Parkinson's disease model. Immunoelectron microscopic examinations confirmed that drebrin-immunoreactive spines became enlarged in the dopamine-denervated striatum of the levodopa-induced dyskinesia model, but not in the Parkinson's disease model. These results suggest that the development of levodopa-induced dyskinesia is associated with enlargement of dendritic spines at corticostriatal excitatory synapses.
Subject(s)
Corpus Striatum/pathology , Dendritic Spines/pathology , Dyskinesia, Drug-Induced/pathology , Neuropeptides/analysis , Parkinsonian Disorders/pathology , Animals , Antiparkinson Agents/adverse effects , Corpus Striatum/metabolism , Dendritic Spines/metabolism , Dyskinesia, Drug-Induced/metabolism , Immunohistochemistry , Levodopa/adverse effects , Male , Microscopy, Immunoelectron , Parkinsonian Disorders/metabolism , Rats , Rats, WistarSubject(s)
Lymphoma/diagnostic imaging , Lymphoma/pathology , Spinal Nerve Roots/diagnostic imaging , Aged , Diffusion Magnetic Resonance Imaging , Humans , Lumbosacral Region/pathology , Lymphoma/complications , Male , Muscular Diseases/diagnostic imaging , Muscular Diseases/etiology , Pain/diagnostic imaging , Pain/etiology , Radiculopathy/diagnostic imaging , Radiculopathy/etiology , Tomography Scanners, X-Ray ComputedABSTRACT
BACKGROUND: l-3,4-dihydroxyphenylalanine (l-dopa) is the most effective drug for Parkinson's disease (PD); however, most PD patients develop motor fluctuations including wearing-off and l-dopa-induced dyskinesia (LID). Amantadine is beneficial for improving the motor symptoms, reducing "off" time, and ameliorating LID, although its long-term efficacy remains unknown. OBJECTIVES: To investigate the effects of amantadine on PD and LID using a rat model with repetitive drug treatment. METHOD: We utilized 6-hydroxydopamine injections to develop a hemiparkinsonian rat model. The rats were assigned to four groups: five rats received l-dopa and benserazide for 31 days, six rats received l-dopa and benserazide plus amantadine for 31 days, five rats received l-dopa and benserazide for 15 days followed by l-dopa and benserazide plus amantadine for 16 days, and five rats received l-dopa and benserazide plus amantadine for 15 days followed by l-dopa and benserazide treatment for 16 days. We evaluated the l-dopa-induced abnormal involuntary movements on treatment days 1, 7, 14, 16, 22, and 29. Subsequently, immunohistochemistry for drebrin was performed. RESULTS: l-dopa-induced abnormal movements were reduced on the first day of amantadine treatment, and these effects disappeared with repetitive treatment. In contrast, the extension of l-dopa "on" time was observed after repetitive amantadine treatment. All groups showed enlarged drebrin immunoreactive dots in the dopamine-denervated striatum, indicating that amantadine did not prevent priming effects of repetitive l-dopa treatment. CONCLUSION: Anti-LID effect of amantadine diminished after repetitive treatment, and the effect of amantadine on wearing-off emerged after repetitive treatment in a hemiparkinsonian rat model. Fluctuations in amantadine effects should be considered when using it in clinical settings.
Subject(s)
Dyskinesia, Drug-Induced , Parkinson Disease , Rats , Animals , Parkinson Disease/drug therapy , Levodopa/pharmacology , Antiparkinson Agents/therapeutic use , Benserazide/adverse effects , Dyskinesia, Drug-Induced/drug therapy , Rats, Sprague-Dawley , Amantadine/pharmacology , Amantadine/therapeutic use , Oxidopamine , Disease Models, AnimalABSTRACT
Background: A rat model of levodopa-induced dyskinesia (LID) showed enlarged axon terminals of striatal direct pathway neurons in the internal segment of the globus pallidus (GPi) with excessive gamma-aminobutyric acid (GABA) storage in them. Massive GABA release to GPi upon levodopa administration determines the emergence of LID. Objectives: We examined whether LID and axon terminal hypertrophy gradually develop with repeated levodopa treatment in Parkinsonian rats to examine if the hypertrophy reflects dyskinesia priming. Methods: 6-hydroxydopamine-lesioned hemiparkinsonian rats were randomly allocated to receive saline injections (placebo group, 14 days; n = 4), injections of 6 mg/kg levodopa methyl ester combined with 12.5 mg/kg benserazide (levodopa-treated groups, 3-day-treatment; n = 4, 7-day-treatment; n = 4, 14-day-treatment; n = 4), or injections of 6 mg/kg levodopa methyl ester with 12.5 mg/kg benserazide and 1 mg/kg 8-hydroxy-2-(di-n-propylamino)tetralin for 14 days (8-OH-DPAT-treated group; n = 4). We evaluated abnormal involuntary movement (AIM) scores and axon terminals in the GPi. Results: The AIM score increased with levodopa treatment, as did the hypertrophy of axon terminals in the GPi, showing an increased number of synaptic vesicles in hypertrophied terminals. Conclusion: Increased GABA storage in axon terminals of the direct pathway neurons represents the priming process of LID.