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Current Opinion in Neurobiology Feb 2024L-DOPA-induced dyskinesia (LID) is the most common form of hyperkinetic movement disorder resulting from altered information processing in the cortico-basal ganglia... (Review)
Review
L-DOPA-induced dyskinesia (LID) is the most common form of hyperkinetic movement disorder resulting from altered information processing in the cortico-basal ganglia network. We here review recent advances clarifying the altered interplay between striatal output pathways in this movement disorder. We also review studies revealing structural and synaptic changes to the striatal microcircuitry and altered cortico-striatal activity dynamics in LID. We furthermore highlight the recent progress made in understanding the involvement of cerebellar and brain stem nuclei. These recent developments illustrate that dyskinesia research continues to provide key insights into cellular and circuit-level plasticity within the cortico-basal ganglia network and its interconnected brain regions.
Topics: Humans; Dyskinesia, Drug-Induced; Levodopa; Basal Ganglia; Corpus Striatum; Brain
PubMed: 38184982
DOI: 10.1016/j.conb.2023.102833 -
Biomolecules Oct 2023A recessive Short Tandem Repeat expansion in has been found to be associated with cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS), and to be a...
A recessive Short Tandem Repeat expansion in has been found to be associated with cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS), and to be a frequent cause of late onset ataxia and sensory neuropathy. The usual procedure for sizing these expansions is based on Southern Blotting (SB), a time-consuming and a relatively imprecise technique. In this paper, we compare SB with Optical Genome Mapping (OGM), a method for detecting Structural Variants (SVs) based on the measurement of distances between fluorescently labelled probes, for the diagnosis of CANVAS and disease spectrum. The two methods are applied to 17 CANVAS patients' blood samples and resulting sizes compared, showing a good agreement. Further, long-read sequencing is used for two patients to investigate the agreement of sizes with either SB or OGM. Our study concludes that OGM represents a viable alternative to SB, allowing for a simpler technique, a more precise sizing of the expansion and ability to expand analysis of SV in the entire genome as opposed to SB which is a locus specific method.
Topics: Humans; Cerebellar Ataxia; Peripheral Nervous System Diseases; Vestibular Diseases; Bilateral Vestibulopathy; Syndrome; Chromosome Mapping
PubMed: 37892228
DOI: 10.3390/biom13101546 -
Brain : a Journal of Neurology Aug 2023Historically, pathological brain lesions provided the foundation for localization of symptoms and therapeutic lesions were used as a treatment for brain diseases. New...
Historically, pathological brain lesions provided the foundation for localization of symptoms and therapeutic lesions were used as a treatment for brain diseases. New medications, functional neuroimaging and deep brain stimulation have led to a decline in lesions in the past few decades. However, recent advances have improved our ability to localize lesion-induced symptoms, including localization to brain circuits rather than individual brain regions. Improved localization can lead to more precise treatment targets, which may mitigate traditional advantages of deep brain stimulation over lesions such as reversibility and tunability. New tools for creating therapeutic brain lesions such as high intensity focused ultrasound allow for lesions to be placed without a skin incision and are already in clinical use for tremor. Although there are limitations, and caution is warranted, improvements in lesion-based localization are refining our therapeutic targets and improved technology is providing new ways to create therapeutic lesions, which together may facilitate the return of the lesion.
Topics: Humans; Brain Mapping; Brain; Brain Diseases; Nervous System Diseases; Tremor
PubMed: 37040563
DOI: 10.1093/brain/awad123 -
Scientific Reports Sep 2023Autonomic symptoms (AS) are critical in Parkinson's disease (PD). We aimed to determine the relative significance of clinical factors allowing predictions about...
Autonomic symptoms (AS) are critical in Parkinson's disease (PD). We aimed to determine the relative significance of clinical factors allowing predictions about incidence of AS, and examine AS profiles among PD patients by motor subtype and its relation to AS. The cross-sectional data of a multicentre sample, including 714 PD patients and 194 healthy controls from Parkinson's Progression Marker Initiative study and Pingchan granule study were analyzed, stratified by PD subtypes [postural instability and gait disturbances (PIGD), tremor dominant (TD), and indeterminate] and domain autonomic dysfunction. Compared with healthy controls, PD patients scored higher in the total Scales for Outcomes in Parkinson's Disease-Autonomic dysfunction score and in several domain scores in particular, and there was a significant overlap in domain AS. Risk factors of individual domain autonomic dysfunction were heterogeneous. PIGD and indeterminate were the predominant subtypes in pupillomotor and thermoregulatory symptoms. TD and indeterminate were more likely to suffer from cardiovascular problem. The odd in sexual dysfunction was significant for PIGD. Gastrointestinal and urinary symptoms seemed not to be associated with a specific subtype. Our study demonstrated that AS were highly heterogeneous and 3 subtypes differed in autonomic performance, providing clues to understand mechanisms underlying AS in PD.
Topics: Humans; Parkinson Disease; Cross-Sectional Studies; Tremor; Primary Dysautonomias; Autonomic Nervous System
PubMed: 37666916
DOI: 10.1038/s41598-023-41662-9 -
Frontiers in Immunology 2023Parkinson's disease (PD) is a common neurodegenerative disorder of middle-aged and elderly people, clinically characterized by resting tremor, myotonia, reduced... (Review)
Review
Parkinson's disease (PD) is a common neurodegenerative disorder of middle-aged and elderly people, clinically characterized by resting tremor, myotonia, reduced movement, and impaired postural balance. Clinically, patients with PD are often administered levodopa (L-DOPA) to improve their symptoms. However, after years of L-DOPA treatment, most patients experience complications of varying severity, including the "on-off phenomenon", decreased efficacy, and levodopa-induced dyskinesia (LID). The development of LID can seriously affect the quality of life of patients, but its pathogenesis is unclear and effective treatments are lacking. Glutamic acid (Glu)-mediated changes in synaptic plasticity play a major role in LID. The N-methyl-D-aspartic acid receptor (NMDAR), an ionotropic glutamate receptor, is closely associated with synaptic plasticity, and neuroinflammation can modulate NMDAR activation or expression; in addition, neuroinflammation may be involved in the development of LID. However, it is not clear whether NMDA receptors are co-regulated with neuroinflammation during LID formation. Here we review how neuroinflammation mediates the development of LID through the regulation of NMDA receptors, and assess whether common anti-inflammatory drugs and NMDA receptor antagonists may be able to mitigate the development of LID through the regulation of central neuroinflammation, thereby providing a new theoretical basis for finding new therapeutic targets for LID.
Topics: Aged; Middle Aged; Humans; Levodopa; Receptors, N-Methyl-D-Aspartate; N-Methylaspartate; Neuroinflammatory Diseases; Quality of Life; Dyskinesia, Drug-Induced; Parkinson Disease; Glutamic Acid
PubMed: 37860013
DOI: 10.3389/fimmu.2023.1253273 -
Neurological Sciences : Official... Sep 2023Mutations in FDXR gene, involved in mitochondrial pathway, cause a rare recessive neurological disorder with variable severity of phenotypes. The most common... (Review)
Review
BACKGROUND AND AIMS
Mutations in FDXR gene, involved in mitochondrial pathway, cause a rare recessive neurological disorder with variable severity of phenotypes. The most common presentation includes optic and/or auditory neuropathy, variably associated to developmental delay or regression, global hypotonia, pyramidal, cerebellar signs, and seizures. The review of clinical findings in previously described cases from literature reveals also a significant incidence of sensorimotor peripheral polyneuropathy (22.72%) and ataxia (43.18%). To date, 44 patients with FDXR mutations have been reported. We describe here on two new patients, siblings, who presented with a quite different phenotype compared to previously described patients.
METHODS
Clinical, neurophysiological, and genetic features of two siblings and a systematic literature review focused on the clinical spectrum of the disease are described.
RESULTS
Both patients presented with an acute-sub-acute onset of peripheral neuropathy and only in later stages of the disease developed the typical features of FDXR-associated disease.
INTERPRETATION
The peculiar clinical presentation at onset and the evolution of the disease in our patients and in some cases revised from the literature shed lights on a new possible phenotype of FDXR-associated disease: a peripheral neuropathy which can mimic an acute inflammatory disease.
Topics: Humans; Ataxia; Cerebellar Ataxia; Diagnosis, Differential; Mutation; Peripheral Nervous System Diseases; Phenotype; Ferredoxin-NADP Reductase
PubMed: 37046037
DOI: 10.1007/s10072-023-06790-0 -
Epilepsia Open Apr 2024Myoclonus classically presents as a brief (10-50 ms duration), non-rhythmic jerk movement. The etiology could vary considerably ranging from self-limited to chronic or... (Review)
Review
Myoclonus classically presents as a brief (10-50 ms duration), non-rhythmic jerk movement. The etiology could vary considerably ranging from self-limited to chronic or even progressive disorders, the latter falling into encephalopathic pictures that need a prompt diagnosis. Beyond the etiological classification, others evaluate myoclonus' body distribution (i.e., clinical classification) or the location of the generator (i.e., neurophysiological classification); particularly, knowing the anatomical source of myoclonus gives inputs on the observable clinical patterns, such as EMG bursts duration or EEG correlate, and guides the therapeutic choices. Among all the chronic disorders, myoclonus often presents itself as a manifestation of epilepsy. In this context, myoclonus has many facets. Myoclonus occurs as one, or the only, seizure manifestation while it can also present as a peculiar type of movement disorder; moreover, its electroclinical features within specific genetically determined epileptic syndromes have seldom been investigated. In this review, following a meeting of recognized experts, we provide an up-to-date overview of the neurophysiology and nosology surrounding myoclonus. Through the dedicated exploration of epileptic syndromes, coupled with pragmatic guidance, we aim to furnish clinicians and researchers alike with practical advice for heightened diagnostic management and refined treatment strategies. PLAIN LANGUAGE SUMMARY: In this work, we described myoclonus, a movement characterized by brief, shock-like jerks. Myoclonus could be present in different diseases and its correct diagnosis helps treatment.
Topics: Humans; Myoclonus; Diagnosis, Differential; Movement Disorders; Epilepsy; Epileptic Syndromes
PubMed: 38334331
DOI: 10.1002/epi4.12917 -
Scientific Reports Oct 2023Dopamine transmission has been implicated in motor and cognitive function. In Parkinson's disease (PD), dopamine replacement using the precursor drug L-DOPA is the... (Meta-Analysis)
Meta-Analysis
Dopamine transmission has been implicated in motor and cognitive function. In Parkinson's disease (PD), dopamine replacement using the precursor drug L-DOPA is the predominant treatment approach, but long-term exposure leads to the onset of dyskinesias (LIDs). Chronic L-DOPA exposure has been associated with changes in gene expression and altered cortico-striatal plasticity. The aim of this research was to assess the functional consequence of long-term L-DOPA exposure on cognitive and motor function using a rodent model of PD. Across two independent experiments, we assessed the impact of chronic L-DOPA exposure, or a control DR agonist, on motor and cognitive function in intact and in hemi parkinsonian rats, in the absence of drug. Abnormal involuntary movements associated with LID were measured and brain tissues were subsequently harvested for immunohistochemical analysis. Exposure to chronic L-DOPA, but not the DR agonist, impaired motor and cognitive function, when animals were tested in the absence of drug. A meta-analysis of the two experiments allowed further dissociation of L-DOPA -treated rats into those that developed LIDs (dyskinetic) and those that did not develop LIDs (non-dyskinetic). This analysis revealed impaired cognitive and motor performance were evident only in dyskinetic, but not in non-dyskinetic, rats. These data reveal a functional consequence of the altered plasticity associated with LID onset and have implications for understanding symptom progression in the clinic.
Topics: Rats; Animals; Levodopa; Parkinson Disease; Dopamine; Rats, Sprague-Dawley; Oxidopamine; Dyskinesia, Drug-Induced; Corpus Striatum; Cognition; Disease Models, Animal
PubMed: 37848479
DOI: 10.1038/s41598-023-44869-y -
Molecular Medicine (Cambridge, Mass.) Mar 2024Loss of dopaminergic neurons underlies the motor symptoms of Parkinson's disease (PD). However stereotypical PD symptoms only manifest after approximately 80% of...
BACKGROUND
Loss of dopaminergic neurons underlies the motor symptoms of Parkinson's disease (PD). However stereotypical PD symptoms only manifest after approximately 80% of dopamine neurons have died making dopamine-related motor phenotypes unreliable markers of the earlier stages of the disease. There are other non-motor symptoms, such as depression, that may present decades before motor symptoms.
METHODS
Because serotonin is implicated in depression, here we use niche, fast electrochemistry paired with mathematical modelling and machine learning to, for the first time, robustly evaluate serotonin neurochemistry in vivo in real time in a toxicological model of Parkinsonism, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP).
RESULTS
Mice treated with acute MPTP had lower concentrations of in vivo, evoked and ambient serotonin in the hippocampus, consistent with the clinical comorbidity of depression with PD. These mice did not chemically respond to SSRI, as strongly as control animals did, following the clinical literature showing that antidepressant success during PD is highly variable. Following L-DOPA administration, using a novel machine learning analysis tool, we observed a dynamic shift from evoked serotonin release in the hippocampus to dopamine release. We hypothesize that this finding shows, in real time, that serotonergic neurons uptake L-DOPA and produce dopamine at the expense of serotonin, supporting the significant clinical correlation between L-DOPA and depression. Finally, we found that this post L-DOPA dopamine release was less regulated, staying in the synapse for longer. This finding is perhaps due to lack of autoreceptor control and may provide a ground from which to study L-DOPA induced dyskinesia.
CONCLUSIONS
These results validate key prior hypotheses about the roles of serotonin during PD and open an avenue to study to potentially improve therapeutics for levodopa-induced dyskinesia and depression.
Topics: Mice; Animals; Levodopa; Dopamine; Serotonin; Antiparkinson Agents; Dyskinesia, Drug-Induced; Parkinson Disease; Parkinsonian Disorders; Biomarkers
PubMed: 38429661
DOI: 10.1186/s10020-023-00773-9 -
Journal of Medical Case Reports Jul 2023Dyskinesia is a movement disorder categorized by involuntary movement of muscle. Although dyskinesia can be brought on by taking medications, it can also be a symptom of...
BACKGROUND
Dyskinesia is a movement disorder categorized by involuntary movement of muscle. Although dyskinesia can be brought on by taking medications, it can also be a symptom of a variety of diseases. Antiepileptic drug-induced involuntary movements have been well researched. Rare reports have been made for dyskinesia, a type of dystonia caused by phenytoin. The mechanism of its occurrence must be succinctly studied.
CASE PRESENTATION
A 53-year-old Asian patient taking phenytoin (100 mg twice daily) experienced symptoms of perioral muscle involuntary movement, impaired speech, and generalized tremors and was admitted to the hospital. Brain magnetic resonance imaging showed significant development of encephalomalacia and porencephaly. The serum phenytoin levels were in the toxic range (33 g/ml). These were suggestive of phenytoin-induced dyskinesia. Levetiracetam and clonazepam were initiated, and the patient showed significant improvement in the symptoms.
CONCLUSION
This case presented a substantial reference value for the differential diagnosis and treatment prognosis of phenytoin-induced dyskinesia. The phenytoin-induced dyskinesia in this patient was successfully reversed with prompt identification and treatment. According to the case study's findings, such people may benefit from periodic therapeutic drug monitoring.
Topics: Humans; Middle Aged; Phenytoin; Dyskinesia, Drug-Induced; Anticonvulsants; Levetiracetam; Dystonia
PubMed: 37475012
DOI: 10.1186/s13256-023-04033-6