Motor symptoms in Parkinson’s disease: A unified framework

Beneficial effects of cysteamine in Thy1-α-Syn mice and induced pluripotent stem cells with a SNCA gene triplication

A number of publications have reported that cysteamine has significant therapeutic effects on several aspects of Parkinson's disease (PD)-related pathology but none of these studies have evaluated its impact on pathological forms of α-Synuclein (α-Syn), one of the main hallmarks of PD. We therefore tested the efficacy of cysteamine on the Thy1-α-Syn mouse model which over-expresses full-length human wild-type α-Syn. Two-month (early stage disease) and 6-month old (late stage disease) mice and littermate controls were treated daily with cysteamine (20 mg/kg, i.p.) to assess the protective and restorative properties of this compound. After 6 weeks of treatment, animals were tested using a battery of motor tests. Cysteamine-treated transgenic mice displayed significant improvements in motor performance as compared to saline-treated transgenic littermates. Post-mortem readouts revealed a reduction in fibrillation, phosphorylation and total levels of overexpresed human α-Syn. To determine if such outcomes extended to human cells, the benefits of cysteamine were additionally tested using 6-hydroxydopamine (6-OHDA) treated neurons differentiated from induced pluripotent stem cells (iPSCs) derived from a PD patient harbouring a triplication of the SNCA gene. SNCA neurons treated with cysteamine exhibited significantly more intact/healthy neurites than cells treated with 6-OHDA alone. Additionally, SNCA neurons treated with cysteamine in the absence of 6-OHDA showed a trend towards lower total α-Syn levels. Overall, our in vivo and in vitro findings suggest that cysteamine can act as a disease-modifying molecule by enhancing -the survival of dopaminergic neurons and reducing pathological forms of α-Syn.

The efficacy of dance for improving motor impairments, non-motor symptoms, and quality of life in Parkinson's disease: A systematic review and meta-analysis

Dance may help individuals living with Parkinson's disease (PD) improve motor and non-motor symptoms that impact quality of life (QOL). The primary aim of this systematic review of randomized controlled trials (RCTs) was to evaluate the efficacy of dance in improving motor and non-motor symptoms of PD and QOL. The secondary aims of this review were to evaluate the methodological quality of included studies by assessing risk of bias across nine categories and to inform the direction of future research. Peer-reviewed RCTs that included people living with PD at all disease stages and ages and measured the effects of a dance intervention longer than one day were included. Sixteen RCTs involving 636 participants with mild to moderate PD were eligible for inclusion in the qualitative synthesis and nine in the meta-analysis. Overall, the reviewed evidence demonstrated that dance can improve motor impairments, specifically balance and motor symptom severity in individuals with mild to moderate PD, and that more research is needed to determine its effects on non-motor symptoms and QOL. RCTs that use a mixed-methods approach and include larger sample sizes will be beneficial in fully characterizing effects and in determining which program elements are most important in bringing about positive, clinically meaningful changes in people with PD.

Tolerability and Blinding of Transcranial Direct Current Stimulation in People with Parkinson's Disease: A Critical Review

Transcranial direct current stimulation (tDCS) is accompanied by transient sensations (e.g., tingling, itching, burning), which may affect treatment outcomes or break the blinding of the study protocol. Assessing tolerability and blinding is integral to providing ample evidence of a "real effect" from the applied stimulation and dispelling the possibility of placebo effects. People with Parkinson's disease (PwPD) endure many motor and non-motor symptoms that might be amenable to tDCS. However, because the disease also affects sensation capabilities, these subjects might report tolerability and blinding differently than other cohorts. Therefore, the purpose of this review was to aggregate the tolerability and blinding reports of tDCS studies in PwPD and recommend a standard tolerability and blinding reporting practice. A literature search of the PubMed and Scopus databases from 1 January 2020 to 1 April 2020 was performed to identify publications that applied tDCS to PwPD. Seventy studies were potentially reviewable, but only 36 (nine with quantitative tolerability reports, 20 with qualitative tolerability reports, and seven that only reported blinding) provided sufficient information to be included in the review. Quantitative information on tDCS tolerability and blinding maintenance in PwPD is scarce, and future reviews and metanalyses should carefully consider the possibility of placebo effects in their included studies.

Development and Differentiation of Midbrain Dopaminergic Neuron: From Bench to Bedside

Parkinson’s Disease (PD) is a neurodegenerative disorder affecting the motor system. It is primarily due to substantial loss of midbrain dopamine (mDA) neurons in the substantia nigra pars compacta and to decreased innervation to the striatum. Although existing drug therapy available can relieve the symptoms in early-stage PD patients, it cannot reverse the pathogenic progression of PD. Thus, regenerating functional mDA neurons in PD patients may be a cure to the disease. The proof-of-principle clinical trials showed that human fetal graft-derived mDA neurons could restore the release of dopamine neurotransmitters, could reinnervate the striatum, and could alleviate clinical symptoms in PD patients. The invention of human-induced pluripotent stem cells (hiPSCs), autologous source of neural progenitors with less ethical consideration, and risk of graft rejection can now be generated in vitro. This advancement also prompts extensive research to decipher important developmental signaling in differentiation, which is key to successful in vitro production of functional mDA neurons and the enabler of mass manufacturing of the cells required for clinical applications. In this review, we summarize the biology and signaling involved in the development of mDA neurons and the current progress and methodology in driving efficient mDA neuron differentiation from pluripotent stem cells.

Possible roles of epigenetics in stem cell therapy for Parkinson's disease

Parkinson's disease (PD) is a neurodegenerative disease with loss of dopaminergic neurons. PD has genetic and epigenetic influences that determine specific changes in the brain. Epigenetic changes result in defective methylation of genes leading to differential gene-expression causing PD. This review provides an overview of stem cell transplantations as potential therapies for PD, with a focus on the epigenetic changes, prior or following transplantation. To date, no reports have addressed epigenetic alterations following stem cell transplantation into the PD brain. Given the potential for affecting the efficacy of stem cell therapy, increased attention needs to be given to the epigenetic processes that occur during stem cell culture and transplantation to maximize the therapeutic potential of stem cells to PD.

Role of Mesenchymal Stem Cells in Counteracting Oxidative Stress-Related Neurodegeneration

Neurodegenerative diseases include a variety of pathologies such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, and so forth, which share many common characteristics such as oxidative stress, glycation, abnormal protein deposition, inflammation, and progressive neuronal loss. The last century has witnessed significant research to identify mechanisms and risk factors contributing to the complex etiopathogenesis of neurodegenerative diseases, such as genetic, vascular/metabolic, and lifestyle-related factors, which often co-occur and interact with each other. Apart from several environmental or genetic factors, in recent years, much evidence hints that impairment in redox homeostasis is a common mechanism in different neurological diseases. However, from a pharmacological perspective, oxidative stress is a difficult target, and antioxidants, the only strategy used so far, have been ineffective or even provoked side effects. In this review, we report an analysis of the recent literature on the role of oxidative stress in Alzheimer’s and Parkinson’s diseases as well as in amyotrophic lateral sclerosis, retinal ganglion cells, and ataxia. Moreover, the contribution of stem cells has been widely explored, looking at their potential in neuronal differentiation and reporting findings on their application in fighting oxidative stress in different neurodegenerative diseases. In particular, the exposure to mesenchymal stem cells or their secretome can be considered as a promising therapeutic strategy to enhance antioxidant capacity and neurotrophin expression while inhibiting pro-inflammatory cytokine secretion, which are common aspects of neurodegenerative pathologies. Further studies are needed to identify a tailored approach for each neurodegenerative disease in order to design more effective stem cell therapeutic strategies to prevent a broad range of neurodegenerative disorders.

Predictors of improved balance performance in persons with Parkinson's disease following a training intervention: analysis of data from an effectiveness-implementation trial

OBJECTIVE

(1) To determine associated factors of improved balance performance after a 10-week HiBalance intervention period, and (2) to determine effects of the programme on modifiable factors found above, considering both groups.

DESIGN

Pre-posttest substudy founded on the outcomes evaluation of an effectiveness-implementation trial.

PARTICIPANTS

Sixty-one participants were allocated the HiBalance training, while 56 were controls.

INTERVENTION

Participants received a 10-week, two times weekly, progressive balance training, that is, HiBalance intervention, led by physical therapists. The intervention was group based and gradually incorporated dual-tasking over the training period. Participants also performed, unsupervised, a 1×/week home exercise programme.

MAIN OUTCOME

The Mini-Balance Evaluation Systems Test (Mini-BESTest) assessed balance performance, and those having improved by ⩾2 points were classified as positive responders. Balance confidence was the secondary outcome.

RESULTS

Fifty-three (87%) participants completed the intervention and 32 (60%) improved their balance scores by ⩾2 points in the intervention group, with 11 (24%) in the control group. The multivariable logistic regression analysis revealed two independently associated factors of improved balance, which included balance confidence (odds ratio (OR) = 0.95; 95% confidence interval (CI) = 0.90-0.99) and attendance of ⩾80% of training sessions (OR = 10.10; 95% CI = 1.71-59.60). The final model demonstrated good fit and acceptable discrimination (area under the curve = 0.84). Secondary analysis revealed a fair relationship (Rho = 0.30; P = 0.044) between improvements in balance confidence and balance performance in the intervention but not control group.

CONCLUSION

Two personal factors were significantly associated with a higher likelihood of improvement in clinically measured balance performance. The HiBalance intervention appears to benefit those with lower balance confidence.

Use of Functional Magnetic Resonance Imaging to Assess How Motor Phenotypes of Parkinson's Disease Respond to Deep Brain Stimulation

BACKGROUND

Deep brain stimulation (DBS) is a well-accepted treatment of Parkinson's disease (PD). Motor phenotypes include tremor-dominant (TD), akinesia-rigidity (AR), and postural instability gait disorder (PIGD). The mechanism of action in how DBS modulates motor symptom relief remains unknown.

OBJECTIVE

Blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) was used to determine whether the functional activity varies in response to DBS depending on PD phenotypes.

MATERIALS AND METHODS

Subjects underwent an fMRI scan with DBS cycling ON and OFF. The effects of DBS cycling on BOLD activation in each phenotype were documented through voxel-wise analysis. For each region of interest, ANOVAs were performed using T-values and covariate analyses were conducted. Further, a correlation analysis was performed comparing stimulation settings to T-values. Lastly, T-values of subjects with motor improvement were compared to those who worsened.

RESULTS

As a group, BOLD activation with DBS-ON resulted in activation in the motor thalamus (p < 0.01) and globus pallidus externa (p < 0.01). AR patients had more activation in the supplementary motor area (SMA) compared to PIGD (p < 0.01) and TD cohorts (p < 0.01). Further, the AR cohort had more activation in primary motor cortex (MI) compared to the TD cohort (p = 0.02). Implanted nuclei (p = 0.01) and phenotype (p = <0.01) affected activity in MI and phenotype alone affected SMA activity (p = <0.01). A positive correlation was seen between thalamic activation and pulse-width (p = 0.03) and between caudate and total electrical energy delivered (p = 0.04).

CONCLUSIONS

These data suggest that DBS modulates network activity differently based on patient motor phenotype. Improved understanding of these differences may further our knowledge about the mechanisms of DBS action on PD motor symptoms and to optimize treatment.

Docosahexaenoic acid protects motor function and increases dopamine synthesis in a rat model of Parkinson's disease via mechanisms associated with increased protein kinase activity in the striatum

Parkinson's disease (PD) is a devastating neurodegenerative disease that leads to motor deficits and selective destruction of nigrostriatal dopaminergic neurons. PD is typically treated by dopamine replacement agents; however, dopamine replacement loses effectiveness in the later stages of the disease. Here, we describe the neuroprotective effects of the omega-3 fatty acid docosahexaenoic acid (DHA) in the medial forebrain bundle 6-hydroxydopamine (6-OHDA) model of advanced-stage PD in rats. We show that daily administration of DHA protects against core symptoms of PD, including deficits in postural stability, gait integrity, and dopamine neurochemistry in motor areas of the striatum. Our results also demonstrate that DHA increases striatal dopamine synthesis via phosphorylation of the rate-limiting catecholamine synthesizing enzyme tyrosine hydroxylase, in a manner dependent on the second messenger-linked protein kinases PKA and PKC. We also show that DHA specifically reverses dopamine loss in the nigrostriatal pathway, with no effect in the mesolimbic or mesocortical pathways. This suggests that DHA is unlikely to produce pharmacotherapeutic or adverse effects that depend on dopamine pathways other than the nigrostriatal pathway. To our knowledge, previous reports have not examined the effects of DHA in such an advanced-stage model, documented that the dopamine synthesizing effects of DHA in vivo are mediated through the activation of protein kinases and regulation of TH activity, or demonstrated specificity to the nigrostriatal pathway. These novel findings corroborate the beneficial effects of omega-3 fatty acids seen in PD patients and suggest that DHA provides a novel means of protecting patients for dopamine neurodegeneration.

MRI biomarkers of motor and non-motor symptoms in Parkinson's disease

Parkinson's disease is a heterogeneous disorder with both motor and non-motor symptoms that contribute to functional impairment. To develop effective, disease modifying treatments for these symptoms, biomarkers are necessary to detect neuropathological changes early in the disease course and monitor changes over time. Advances in MRI scan sequences and analytical techniques present numerous promising metrics to detect changes within the nigrostriatal system, implicated in the cardinal motor symptoms of the disease, and detect broader dysfunction involved in the non-motor symptoms, such as cognitive impairment. There is emerging evidence that iron sensitive, neuromelanin sensitive, diffusion sensitive, and resting state functional magnetic imaging measures can capture changes within the nigrostriatal system. Iron, neuromelanin, and diffusion sensitive measures demonstrate high specificity and sensitivity in distinguishing Parkinson's disease relative to controls, with inconsistent results differentiating Parkinson's disease relative to atypical parkinsonian disorders. They may also serve as useful monitoring biomarkers, with each possibly detecting different aspects of the disease course (early nigrosome changes versus broader substantia nigra changes). Investigations of non-motor symptoms, such as cognitive impairment, require careful consideration of the nature of cognitive deficits to characterize regional and network specific impairment. While the early, executive dysfunction observed is consistent with nigrostriatal degeneration, the memory and visuospatial impairments, the harbingers of a dementia process reflect dopaminergic independent dysfunction involving broader regions of the brain.

Quantitative Measurement of Rigidity in Parkinson´s Disease: A Systematic Review

Rigidity is one of the cardinal symptoms of Parkinson´s disease (PD). Present in up 89% of cases, it is typically assessed with clinical scales. However, these instruments show limitations due to their subjectivity and poor intra- and inter-rater reliability. To compile all of the objective quantitative methods used to assess rigidity in PD and to study their validity and reliability, a systematic review was conducted using the Web of Science, PubMed, and Scopus databases. Studies from January 1975 to June 2019 were included, all of which were written in English. The Strengthening the Reporting of observational studies in Epidemiology Statement (STROBE) checklist for observational studies was used to assess the methodological rigor of the included studies. Thirty-six studies were included. Rigidity was quantitatively assessed in three ways, using servomotors, inertial sensors, and biomechanical and neurophysiological study of muscles. All methods showed good validity and reliability, good correlation with clinical scales, and were useful for detecting rigidity and studying its evolution. People with PD exhibit higher values in terms of objective muscle stiffness than healthy controls. Rigidity depends on the angular velocity and articular amplitude of the mobilization applied. There are objective, valid, and reliable methods that can be used to quantitatively assess rigidity in people with PD.

Degradation of Neuronal Encoding of Speech in the Subthalamic Nucleus in Parkinson's Disease

BACKGROUND

Most of the patients with Parkinson's disease suffer from speech disorders characterized mainly by dysarthria and hypophonia.

OBJECTIVE

To understand the deterioration of speech in the course of Parkinson's disease.

METHODS

We intraoperatively recorded single neuron activity in the subthalamic nucleus of 18 neurosurgical patients with Parkinson's disease undergoing implantation of deep brain stimulator while patients articulated 5 vowel sounds.

RESULTS

Here, we report that single subthalamic neurons encode individual vowel phonemes and employ 1 of 2 encoding schemes: broad or sharp tuning. Broadly tuned units respond to all examined phonemes, each with a different firing rate, whereas sharply tuned ones are specific to 1 to 2 phonemes. We then show that in comparison with patients without speech deficits, the spiking activity in patients with speech disorders was lower during speech production, overt or imagined, but not during perception. However, patients with speech disorders employed a larger percentage of the neurons for the aforementioned tasks. Whereas the lower firing rates affect mainly sharply tuned units, the extra units used a broad tuning encoding scheme.

CONCLUSION

Our findings suggest mechanisms of neuronal degradation due to Parkinsonian speech disorders and their possible compensation. As impairment in sharply tuned units may be compensated by broadly tuned ones, the proposed compensation model appears to be suboptimal, lending support to the persistence of speech disorders in the course of the disease.

Attention/memory complaint is correlated with motor speech disorder in Parkinson's disease

BACKGROUND

The mechanisms underlying the online modulation of motor speech in Parkinson's disease (PD) have not been determined. Moreover, medical and rehabilitation interventions for PD-associated motor speech disorder (MSD) have a poor long-term prognosis.

METHODS

To compare risk factors in PD patients with MSD to those without MSD (non-MSD) and determine predictive independent risk factors correlated with the MSD phenotype, we enrolled 314 PD patients, including 250 with and 64 without MSD. We compared demographic, characteristic data, as well as PD-associated evaluations between the MSD group and non-MSD group.

RESULTS

Univariate analysis showed that demographic characteristics, including occupation, educational level, monthly income and speaking background; clinical characteristics, including lesions in the frontal and temporal lobes, and concurrent dysphagia; and PD-associated evaluations, including the activity of daily living (ADL) score, non-motor symptoms scale (NMSS) domain 4 score (perceptual problem), and NMSS domain 5 score (attention/memory) were all significantly different between the MSD and non-MSD group (all P < 0.05). Multivariate logistic regression analysis showed that educational level, frontal lesions, and NMSS domain 5 score (attention/memory) were independent risk factors for PD-associated MSD (all P < 0.005).

CONCLUSIONS

We determined an association between MSD phenotype and cognitive impairment, reflected by low-level education and related clinical profiles. Moreover, attention and memory dysfunction may play key roles in the progression of MSD in PD patients. Further studies are required to detail the mechanism underlying abnormal speech motor modulation in PD patients. Early cognitive intervention may enhance rehabilitation management and motor speech function in patients with PD-associated MSD.

Electrochemical biosensors for the detection and study of α-synuclein related to Parkinson's disease - A review

Parkinson's disease (PD) is a long-term degenerative disorder that affects predominately dopaminergic neurons in the substantia nigra, which mainly control movement. Alpha-synuclein (α-syn) is a major constituent of Lewy bodies that are reported to be the most important toxic species in the brain of PD patients. In this critical review, we highlight novel electrochemical biosensors that have been recently developed utilizing aptamers and antibodies in connection with various nanomaterials to study biomarkers related to PD such as α-syn. We also review several research articles that have utilized electrochemical biosensors to study the interaction of α-syn with biometals as well as small molecules such as clioquinol, (-)-epigallocatechin-3-gallate (EGCG) and baicalein. Due to the significant advances in nanomaterials in the past decade, electrochemical biosensors capable of detecting multiple biomarkers in clinically relevant samples in real-time have been achieved. This may facilitate the path towards commercialization of electrochemical biosensors for clinical applications and high-throughput screening of small molecules for structure-activity relationship (SAR) studies.

Quantitative Assessment of Finger Movement Profile in a Visual-Motor Task Based on a Tablet Computer: The Application in Parkinson's Disease

BACKGROUND/OBJECTIVE

Easily applicable, quantitative assessment of movement is widely needed in various clinical settings, especially in the evaluation of Parkinson's disease (PD).

METHODS

We developed a highly repeatable tablet computer-based finger movement assessment system (FMAS) to record finger movement profile in a visual-motor task both in PD (n = 217) and healthy participants (n = 221).

RESULTS

We found age-related declines in finger movement performance among the healthy participants but not in PD patients with the FMAS. Significant differences in movement time (MT) and latency/MT ratio but not in latency were observed in PD patients as compared with healthy subjects (P < 0.000). Meanwhile, we identified the latency/MT ratio as the optimal parameter to differentiate PD from age-matched healthy subjects in an age-independent manner (cut-off 1.08 with corresponding AUC = 0.861). In addition, a significant correlation was found between finger movement parameters and the Hoehn and Yahr scale (H-Y scale), UPDRS III score and the duration of the disease in PD patients (P < 0.01).

CONCLUSION

It was suggested that the tablet computer-based evaluation of finger movement provided an easily applicable quantitative method to assess the conditions of PD patients.

Quantitative Susceptibility Mapping and Resting State Network Analyses in Parkinsonian Phenotypes-A Systematic Review of the Literature

An imbalance of iron metabolism with consecutive aggregation of α-synuclein and axonal degeneration of neurons has been postulated as the main pathological feature in the development of Parkinson’s disease (PD). Quantitative susceptibility mapping (QSM) is a new imaging technique, which enables to measure structural changes caused by defective iron deposition in parkinsonian brains. Due to its novelty, its potential as a new imaging technique remains elusive for disease-specific characterization of motor and non-motor symptoms (characterizing the individual parkinsonian phenotype). Functional network changes associated with these symptoms are however frequently described for both magnetoencephalography (MEG) and resting state functional magnetic imaging (rs-fMRI). Here, we performed a systematic review of the current literature about QSM imaging, MEG and rs-fMRI in order to collect existing data about structural and functional changes caused by motor and non-motor symptoms in PD. Whereas all three techniques provide an effect in the motor domain, the understanding of network changes caused by non-motor symptoms is much more lacking for MEG and rs-fMRI, and does not yet really exist for QSM imaging. In order to better understand the influence of pathological iron distribution onto the functional outcome, whole-brain QSM analyses should be integrated in functional analyses (especially for the non-motor domain), to enable a proper pathophysiological interpretation of MEG and rs-fMRI network changes in PD. Herewith, a better understanding of the relationship between neuropathological changes, functional network changes and clinical phenotype might become possible.

Mental representation of the body in action in Parkinson's disease

Mixed findings characterize studies in Parkinson's disease (PD): some studies indicate a relationship between physical impairments and the ability to mentally represent the body, while others suggest spared abilities for this cognitive function. To clarify the matter, in the present study we explored the mental representations of the body in action in the same PD patients, taking also into account lateralization of symptoms and visual imagery skills. 10 PD patients with left- (lPD), 10 with right (rPD) lateralized symptoms (lPD), and 20 matched healthy controls have been recruited for the study. All patients were screened for neuropsychological impairments. To explore a more implicit component we used the hand laterality task (HLT), while the mental motor chronometry (MMC) was used to explore a more explicit one. Two control tasks, with objects instead of body parts, were administered to control for visual imagery skills. In the HLT, we detected the effects of biomechanical constraints effects in both controls and PD patients. In the latter group, importantly, this was true independently from lateralization of symptoms. In the MMC, we found the expected positive correlation between executed and imagined movements for both hands in controls only, while all PD patients, again independently form lateralization, only showed this effect for the left hand. In terms of visual imagery, only rPD patients differed from controls when asked to implicitly rotate letters, and in terms of accuracy only. However, this difference is explained by executive functions measured through the neuropsychological assessment rather than by a "pure" visual imagery impairment. In summary, our findings suggest that two different aspects of the mental representations of the body in action, one more implicit and the other more explicit, can be differently affected by PD. These impairments are unlikely explained by a basic visual imagery deficit. When present, impairments concern a higher dimension, related to motor functions and awareness, and not driven by sensory impairments, as shown by the independence of effects from physical laterality of symptoms.

Four main therapeutic keys for Parkinson's disease: A mini review

OBJECTIVES

Parkinson's disease (PD) is characterized by motor and cognitive dysfunctions. The progressive degeneration of dopamine-producing neurons that are present in the substantia nigra pars compacta (SNpc) has been the main focus of study and PD therapies since ages.

MATERIALS AND METHODS

In this manuscript, a systematic revision of experimental and clinical evidence of PD-associated cell process was conducted.

RESULTS

Classically, the damage in the dopaminergic neuronal circuits of SNpc is favored by reactive oxidative/nitrosative stress, leading to cell death. Interestingly, the therapy for PD has only focused on avoiding the symptom progression but not in finding a complete reversion of the disease. Recent evidence suggests that the renin-angiotensin system imbalance and neuroinflammation are the main keys in the progression of experimental PD.

CONCLUSION

The progression of neurodegeneration in SNpc is due to the complex interaction of multiple processes. In this review, we analyzed the main contribution of four cellular processes and discussed in the perspective of novel experimental approaches.

Inhospital Complications of Patients With Neuromuscular Disorders Undergoing Total Joint Arthroplasty

INTRODUCTION

Orthopaedic surgeons are wary of patients with neuromuscular (NM) diseases as a result of perceived poor outcomes and lack of data regarding complication risks. We determined the prevalence of patients with NM disease undergoing total joint arthroplasty (TJA) and characterized its relationship with in-hospital complications, prolonged length of stay, and total charges.

METHODS

Data from the Nationwide Inpatient Sample from 2005 to 2014 was used for this retrospective cohort study to identify 8,028,435 discharges with total joint arthroplasty. International Classification of Diseases, Ninth Revision, Clinical Modification codes were used to identify 91,420 patients who had discharge diagnoses for any of the NM disorders of interest: Parkinson disease, multiple sclerosis, cerebral palsy, cerebrovascular disease resulting in lower extremity paralysis, myotonic dystrophy, myasthenia gravis, myositis (dermatomyositis, polymyositis, and inclusion-body myositis), spinal muscular atrophy type III, poliomyelitis, spinal cord injury, and amyotrophic lateral sclerosis. Logistic regression was used to estimate the association between NM disease and perioperative outcomes, including inpatient adverse events, length of stay, mortality, and hospital charges adjusted for demographic, hospital, and clinical characteristics.

RESULTS

NM patients undergoing TJA had increased odds of total surgical complications (odds ratio [OR] = 1.21; 95% confidence interval [CI], 1.17 to 1.25; P < 0.0001), medical complications (OR = 1.41; 95% CI, 1.36 to 1.46; P < 0.0001), and overall complications (OR = 1.32; 95% CI, 1.28 to 1.36; P < 0.0001) compared with non-NM patients. Specifically, NM patients had increased odds of prosthetic complications (OR = 1.09; 95% CI, 0.84 to 1.42; P = 0.003), wound dehiscence (OR = 5.00; 95% CI, 1.57 to 15.94; P = 0.0002), acute postoperative anemia (OR = 1.20; 95% CI, 1.16 to 1.24; P < 0.0001), altered mental status (OR = 2.59; 95% CI, 2.24 to 2.99; P < 0.0001), urinary tract infection (OR = 1.45; 95% CI, 1.34 to 1.56; P < 0.0001), and deep vein thrombosis (OR = 1.27; 95% CI, 1.02 to 1.58; P = 0.021). No difference of in-hospital mortality was observed (P = 0.155).

DISCUSSION

Because more patients with NM disease become candidates of TJA, a team of neurologists, anesthesiologists, therapists, and orthopaedic surgeon is required to anticipate, prevent, and manage potential complications identified in this study.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Dopamine Released from TiO2 Semicrystalline Lattice Implants Attenuates Motor Symptoms in Rats Treated with 6-Hydroxydopamine

The motor dysfunction featured by patients aggrieved by Parkinson's disease (PD) results from the reduction of dopamine (DA) availability in the caudate nucleus (CN). Restituting CN DA levels is therefore essential to ameliorate PD motor deficits. In this regard, nanotechnology may offer solutions to restore CN DA availability. DA, however, can be rapidly oxidized into toxic compounds if made available in situ, unprotected. Then, we tested whether a semicrystalline TiO₂ lattice, implanted into the CN of 6-hydroxydopamine (6-OHDA)-lesioned, hemiparkinsonian rats, was able to release DA during a time window sufficient to attenuate motor symptoms while protecting it from the ongoing oxidation. Accordingly, implanted semicrystalline TiO₂ lattices released incremental amounts of DA into the CN of lesioned rats. Motor symptoms were already attenuated by the 1st month and significantly reduced 2 months after implantation. These effects were specific since TiO₂ lattices alone did not modify motor symptoms in lesioned rats. DA-unloaded or -loaded TiO₂ lattices did not produce obvious symptoms of systemic or neurological toxicity nor significantly increased CN lipid peroxidation in implanted, lesioned rats at the time of sacrifice. Our results thus support that loaded TiO₂ lattices are capable of releasing DA while protecting it from the ongoing oxidation when implanted into the brain. Their implantation does not cause noticeable systemic or local toxicity. On the contrary, they attenuated motor symptoms in hemiparkinsonian rats.

Different Dopaminergic Dysfunctions Underlying Parkinsonian Akinesia and Tremor

Although the occurrence of Parkinsonian akinesia and tremor is traditionally associated to dopaminergic degeneration, the multifaceted neural processes that cause these impairments are not fully understood. As a consequence, current dopamine medications cannot be tailored to the specific dysfunctions of patients with the result that generic drug therapies produce different effects on akinesia and tremor. This article proposes a computational model focusing on the role of dopamine impairments in the occurrence of akinesia and resting tremor. The model has three key features, to date never integrated in a single computational system: (a) an architecture constrained on the basis of the relevant known system-level anatomy of the basal ganglia-thalamo-cortical loops; (b) spiking neurons with physiologically-constrained parameters; (c) a detailed simulation of the effects of both phasic and tonic dopamine release. The model exhibits a neural dynamics compatible with that recorded in the brain of primates and humans. Moreover, it suggests that akinesia might involve both tonic and phasic dopamine dysregulations whereas resting tremor might be primarily caused by impairments involving tonic dopamine release and the responsiveness of dopamine receptors. These results could lead to develop new therapies based on a system-level view of the Parkinson's disease and targeting phasic and tonic dopamine in differential ways.

Establishing a framework for neuropathological correlates and glymphatic system functioning in Parkinson's disease

Recent evidence has advanced our understanding of the function of sleep to include removal of neurotoxic protein aggregates via the glymphatic system. However, most research on the glymphatic system utilizes animal models, and the function of waste clearance processes in humans remains unclear. Understanding glymphatic function offers new insight into the development of neurodegenerative diseases that result from toxic protein inclusions, particularly those characterized by neuropathological sleep dysfunction, like Parkinson's disease (PD). In PD, we propose that glymphatic flow may be compromised due to the combined neurotoxic effects of alpha-synuclein protein aggregates and deteriorated dopaminergic neurons that are linked to altered REM sleep, circadian rhythms, and clock gene dysfunction. This review highlights the importance of understanding the functional role of glymphatic system disturbance in neurodegenerative disorders and the subsequent clinical and neuropathological effects on disease progression. Future research initiatives utilizing noninvasive brain imaging methods in human subjects with PD are warranted, as in vivo identification of functional biomarkers in glymphatic system functioning may improve clinical diagnosis and treatment of PD.

Towards understanding neural network signatures of motor skill learning in Parkinson's disease and healthy aging

In the past decade, neurorehabilitation has been shown to be an effective therapeutic supplement for patients with Parkinson's disease (PD). However, patients still experience severe problems with the consolidation of learned motor skills. Knowledge on the neural correlates underlying this process is thus essential to optimize rehabilitation for PD. This review investigates the existing studies on neural network connectivity changes in relation to motor learning in healthy aging and PD and critically evaluates the imaging methods used from a methodological point of view. The results indicate that despite neurodegeneration there is still potential to modify connectivity within and between motor and cognitive networks in response to motor training, although these alterations largely bypass the most affected regions in PD. However, so far training-related changes are inferred and possible relationships are not substantiated by brain-behavior correlations. Furthermore, the studies included suffer from many methodological drawbacks. This review also highlights the potential for using neural network measures as predictors for the response to rehabilitation, mainly based on work in young healthy adults. We speculate that future approaches, including graph theory and multimodal neuroimaging, may be more sensitive than brain activation patterns and model-based connectivity maps to capture the effects of motor learning. Overall, this review suggests that methodological developments in neuroimaging will eventually provide more detailed knowledge on how neural networks are modified by training, thereby paving the way for optimized neurorehabilitation for patients.

Immune Signaling in Neurodegeneration

Neurodegenerative diseases of the central nervous system progressively rob patients of their memory, motor function, and ability to perform daily tasks. Advances in genetics and animal models are beginning to unearth an unexpected role of the immune system in disease onset and pathogenesis; however, the role of cytokines, growth factors, and other immune signaling pathways in disease pathogenesis is still being examined. Here we review recent genetic risk and genome-wide association studies and emerging mechanisms for three key immune pathways implicated in disease, the growth factor TGF-β, the complement cascade, and the extracellular receptor TREM2. These immune signaling pathways are important under both healthy and neurodegenerative conditions, and recent work has highlighted new functional aspects of their signaling. Finally, we assess future directions for immune-related research in neurodegeneration and potential avenues for immune-related therapies.

The beta oscillation conditions in a simplified basal ganglia network

Parkinson's disease is a type of motor dysfunction disease that is induced mainly by abnormal interactions between the subthalamic nucleus (STN) and globus pallidus (GP) neurons. Periodic oscillatory activities with frequencies of 13-30 Hz are the main physiological characteristics of Parkinson's disease. In this paper, we built a class of STN-GP networks to explore beta oscillation conditions. A theoretical formula was obtained for generating oscillations without internal GP connections. Based on this formula, we studied the effects of cortex inputs, striatum inputs, coupling weights and delays on oscillation conditions, and the theoretical results are in good agreement with the numerical results. The onset mechanism can be explained by the model, and the internal GP connection has little effect on oscillations. Finally, we compared oscillation conditions with those in previous studies and found that the delays and coupling weights required for generating oscillations may decrease as the number of nuclei increases. We hope that the results obtained will inspire future theoretical and experimental studies.

Effects of α-Synuclein Monomers Administration in the Gigantocellular Reticular Nucleus on Neurotransmission in Mouse Model

The aim of the study was to examine the Braak's hypothesis to explain the spreading and distribution of the neuropathological changes observed in the course of Parkinson's disease among ascending neuroanatomical regions. We investigated the neurotransmitter levels (monoamines and amino acid concentration) as well as tyrosine hydroxylase (TH) and transglutaminase-2 (TG2) mRNA expression in the mouse striata (ST) after intracerebral α-synuclein (ASN) administration into gigantocellular reticular nucleus (Gi). Male C57BL/10 Tar mice were used in this study. ASN was administrated by stereotactic injection into Gi area (4 μl; 1 μg/μl) and mice were decapitated after 1, 4 or 12 weeks post injection. The neurotransmitters concentration in ST were evaluated using HPLC detection. TH and TG2 mRNA expression were examined by Real-Time PCR method. At 4 and 12 weeks after ASN administration we observed decrease of DA concentration in ST relative to control groups and we found a significantly higher concentration one of the DA metabolites-DOPAC. At these time points, we also noticed the increase in DA turnover determined as DOPAC/DA ratio. Additionally, at 4 and 12 weeks after ASN injection we noted decreasing of TH mRNA expression. Our findings corresponds with the Braak's theory about the presence of the first neuropathological changes within brainstem and then with time affecting higher neuroanatomical regions. These results obtained after administration of ASN monomers to the Gi area may be useful to explain the pathogenesis of Parkinson's disease.

Defective Tool Embodiment in Body Representation of Individuals Affected by Parkinson's Disease: A Preliminary Study

When efficiently used for action, tools become part of the body, with effect on the spatial-temporal movement parameters and body size perception. Until now, no previous investigation has been reported about tool embodiment in Parkinson’s disease (PD), which is a neurological disease characterized by several sensory and motor symptoms affecting body and action. We enrolled 14 individuals affected by PD and 18 healthy individuals as controls. We studied the spatial-temporal parameters on self-paced free pointing movement task, via an optoelectronic system, before and after a short training in which a 27-cm long rod was used to point toward a far target. Moreover, we investigated changes in estimation of arm length through the Tactile Estimation Task. After the tool-use training, controls showed changes in spatial-temporal parameters: they were slower to perform movements and reported a higher value of deceleration than the baseline. However, such a difference did not emerge in the PD individuals. In the Tactile Discrimination Task, no difference emerged before and after the tool-use training in both groups. Our results were suggestive of possible difficulties of the tool embodiment process in PD. We discussed our results in relation to aberrant multisensory integration as well as in terms of the effect of PD sensory and motor symptoms on body schema plasticity. The present study points at a novel way to conceive PD sensory motor signs and symptoms in terms of their effect on individuals’ body representation.

Face-to-trait inferences in patients with Parkinson's disease

Introduction: Parkinson's disease is a progressive neurological disorder characterized by the preferential loss of dopaminergic neurons in the substantia nigra, which project to the striatum. The disease is characterized by prominent motor symptoms, which are its cardinal features. Consequently, Parkinson's disease has been primarily considered a disorder of movement. However, increasing evidence has indicated that Parkinson's disease affects not only the motor domain but also the cognitive domain. Increasing evidence indicates that patients with Parkinson's disease have an impaired ability to recognize emotional facial expressions. Recent studies have reported that other socially relevant information from faces, including face-to-trait inferences for traits such as dominance, competence, and trustworthiness, may be processed in subcortical regions, including the amygdala and caudate nucleus. However, the mechanism underlying the processing of face-to-trait inferences for these traits in patients with Parkinson's disease is still unknown. This study aimed to assess the face-to-trait inference ability in patients with Parkinson's disease. Method: Face-to-trait inference ability was assessed using a forced-choice method in patients with Parkinson's disease and age- and sex-matched healthy controls. Results: Overall correct face-to-trait inferences occurred significantly less frequently in the Parkinson's disease group than in the control group. Further analysis revealed a significant interaction between groups and the extent to which facial features were exaggerated. Conclusions: The present results suggest that the sensitivity of face-to-trait processing was linear in the Parkinson's disease group but not in the healthy controls. These deficits may have resulted from dysfunction in subcortical regions, which may also lead to impairment in other social inferential abilities in patients with Parkinson's disease.

Biochemical Profiling of the Brain and Blood Metabolome in a Mouse Model of Prodromal Parkinson's Disease Reveals Distinct Metabolic Profiles

Parkinson's disease is the second most common neurodegenerative disease. In the vast majority of cases the origin is not genetic and the cause is not well understood, although progressive accumulation of α-synuclein aggregates appears central to the pathogenesis. Currently, treatments that slow disease progression are lacking, and there are no robust biomarkers that can facilitate the development of such treatments or act as aids in early diagnosis. Therefore, we have defined metabolomic changes in the brain and serum in an animal model of prodromal Parkinson's disease. We biochemically profiled the brain tissue and serum in a mouse model with progressive synucleinopathy propagation in the brain triggered by unilateral injection of preformed α-synuclein fibrils in the olfactory bulb. In total, we accurately identified and quantified 71 metabolites in the brain and 182 in serum using ¹H NMR and targeted mass spectrometry, respectively. Using multivariate analysis, we accurately identified which metabolites explain the most variation between cases and controls. Using pathway enrichment analysis, we highlight significantly perturbed biochemical pathways in the brain and correlate these with the progression of the disease. Furthermore, we identified the top six discriminatory metabolites and were able to develop a model capable of identifying animals with the pathology from healthy controls with high accuracy (AUC (95% CI) = 0.861 (0.755-0.968)). Our study highlights the utility of metabolomics in identifying elements of Parkinson's disease pathogenesis and for the development of early diagnostic biomarkers of the disease.

Oral Health of Parkinson's Disease Patients: A Case-Control Study

The aim of the study was to examine the oral health status of Parkinson's disease (PD) patients, to compare their oral health status to that of a control group, and to relate it to the duration and severity of PD. Materials and Methods. 74 PD patients and 74 controls were interviewed and orally examined. Among PD patients, the duration and the Hoehn and Yahr stage (HY) of the disease were registered. Results. More PD patients than controls reported oral hygiene care support as well as chewing/biting problems, taste disturbance, tooth mobility, and xerostomia, whereas dentate patients had more teeth with carious lesions, tooth root remnants, and biofilm. Both longer duration and higher HY were associated with more chewing problems and, in dentates, more teeth with restorations. In dentates, longer duration of the disease was associated with higher number of mobile teeth. Higher HY was associated with more oral hygiene care support as well as biting problems and, in dentates, more teeth with carious lesions and tooth root remnants. Conclusions. Comparatively, PD patients had weakened oral health status and reduced oral hygiene care. Both duration and severity of the disease were associated with more oral health and hygiene care problems.

Taurine protects dopaminergic neurons in a mouse Parkinson's disease model through inhibition of microglial M1 polarization

Microglia-mediated neuroinflammation is implicated in multiple neurodegenerative disorders, including Parkinson’s disease (PD). Hence, the modulatioein of sustained microglial activation may have therapeutic potential. This study is designed to test the neuroprotective efficacy of taurine, a major intracellular free β-amino acid in mammalian tissues, by using paraquat and maneb-induced PD model. Results showed that mice intoxicated with paraquat and maneb displayed progressive dopaminergic neurodegeneration and motor deficits, which was significantly ameliorated by taurine. Taurine also attenuated the aggregation of α-synuclein in paraquat and maneb-intoxicated mice. Mechanistically, taurine suppressed paraquat and maneb-induced microglial activation. Moreover, depletion of microglia abrogated the dopaminergic neuroprotective effects of taurine, revealing the role of microglial activation in taurine-afforded neuroprotection. Subsequently, we found that taurine suppressed paraquat and maneb-induced microglial M1 polarization and gene expression levels of proinflammatory factors. Furthermore, taurine was shown to be able to inhibit the activation of NADPH oxidase (NOX2) by interfering with membrane translocation of cytosolic subunit, p47^phox and nuclear factor-kappa B (NF-κB) pathway, two key factors for the initiation and maintenance of M1 microglial inflammatory response. Altogether, our results showed that taurine exerted dopaminergic neuroprotection through inactivation of microglia-mediated neuroinflammation, providing a promising avenue and candidate for the potential therapy for patients suffering from PD.

Total Joint Arthroplasty in Patients With Parkinson's Disease: Survivorship, Outcomes, and Reasons for Failure

BACKGROUND

Gait instability and muscle rigidity are known characteristics of Parkinson's disease (PD), putting PD patients at risk for complications following total joint arthroplasty (TJA). The outcomes of Parkinson's patients undergoing TJA are largely unknown. This study evaluated the outcomes of TJA in this population.

METHODS

A single institution retrospective cohort of 123 TJAs (52 hips, 71 knees) from 2000 to 2016 was reviewed. An electronic chart query was performed using International Classification of Diseases, Ninth revision codes to identify this population. A manual chart review was performed to confirm the diagnosis of PD, survivorship, and reason for failure. A control cohort was matched 2:1 based on age, body mass index, joint, and comorbidities. Outcomes were assessed using revision for any reason as the primary endpoint. Functional outcomes were assessed using Short-Form 12 scores.

RESULTS

At an average follow-up of 5.3 years, 23.6% of patients required revision surgery. The most common reasons for revision for total knee arthroplasty (TKA) were periprosthetic infection and for total hip arthroplasty (THA) were periprosthetic fracture and dislocation. Overall survivorship of TJA at years 2, 5, and 10 respectively were 94.9%, 87.9%, and 72.3%. The survivorship of TKA was 95.2%, 89.8%, and 66.2%. THA implant survivorship was 94.3%, 85.3%, and 78.7%. Functional score improvement was less in PD cohort than the control.

CONCLUSION

Patients with PD are at increased risk for complications, particularly periprosthetic infection following TKA and periprosthetic fracture and dislocation following THA. Despite this increased risk of complications, patients with PD can demonstrate improved functional outcomes but not as high as patients without PD. Patients with PD should be counseled appropriately prior to undergoing TJA.

Dual-task Interference Disrupts Parkinson's Gait Across Multiple Cognitive Domains

Gait dysfunction, a hallmark of Parkinson's disease, contributes to a relatively high incidence of falling. Gait function is further diminished during the performance of a motor-cognitive task (i.e., dual-task). It is unclear if Parkinson's disease-related dual-task deficits are related to a specific area of cognitive function or are the result of a more global decline in executive function. The aim of this project was to systematically evaluate gait performance to determine if gait dysfunction is restricted to certain types of executive function or a global phenomenon in individuals with Parkinson's disease. Twenty-three individuals with mild-moderate Parkinson's disease completed a series of dual-task conditions in which gait was paired with cognitive tasks requiring: working memory (0, 1, and 2-back), attention and problem solving (serial-7 subtraction), verbal memory (digit recall), semantic memory (Controlled Oral Word Association) and information processing speed (visual Stroop test). The results demonstrate that individuals with mild-moderate Parkinson's disease have a generalized worsening of spatial-temporal gait parameters regardless of the specific cognitive demand being performed concurrently. Overall, gait velocity decreased (p < 0.01) and stride and stance time both increased (p < 0.01) across all cognitive conditions. The attention and problem solving task resulted in the greatest number of gait parameter decrements. Results indicated that performance on cognitive tasks remained unchanged from single-task to dual-task conditions. Diminished gait performance under dual-task conditions across different cognitive function domains suggests a global Parkinson's disease-related deficit in information processing and regulation of gait.

Characteristics associated with freezing of gait in actual daily living in Parkinson's disease

[Purpose] Parkinson’s disease (PD) patients often freeze in actual daily living but seldom in clinical setting. This study aimed to identify the factors contributing to freezing of gait (FOG). [Subjects and Methods] The participants included 28 adults with PD. Principal component analysis was used to investigate the characteristics of 14 common FOG situations adopted from previous studies. Cluster analysis classified the subjects into four groups. Kruskal-Wallis test was performed to compare the PD Questionnaire-39 mobility dimension between the groups. [Results] The major variables of the first principal component in 14 FOG situations were unfamiliar places, unpredictable schedule changes, entering an automatic door, when another person suddenly crossed, and change in the walking surface. These situations were unrelated to the second principal component. Getting on/off a public transport and crowded places were major variables for the second principal component, and related to both the first and second principal components. Although fatigue was the most frequent FOG situation, not all principal components were influenced. The values of the PD Questionnaire-39 revealed significant differences between the groups. [Conclusion] Actual FOG situations may be categorized into (1) task complexity, (2) both task complexity and emotional factors, and (3) fatigue as decreased attentional resources.

Technology-Assisted Rehabilitation of Writing Skills in Parkinson's Disease: Visual Cueing versus Intelligent Feedback

Recent research showed that visual cueing can have both beneficial and detrimental effects on handwriting of patients with Parkinson's disease (PD) and healthy controls depending on the circumstances. Hence, using other sensory modalities to deliver cueing or feedback may be a valuable alternative. Therefore, the current study compared the effects of short-term training with either continuous visual cues or intermittent intelligent verbal feedback. Ten PD patients and nine healthy controls were randomly assigned to one of these training modes. To assess transfer of learning, writing performance was assessed in the absence of cueing and feedback on both trained and untrained writing sequences. The feedback pen and a touch-sensitive writing tablet were used for testing. Both training types resulted in improved writing amplitudes for the trained and untrained sequences. In conclusion, these results suggest that the feedback pen is a valuable tool to implement writing training in a tailor-made fashion for people with PD. Future studies should include larger sample sizes and different subgroups of PD for long-term training with the feedback pen.

Tiny But Mighty: Promising Roles of MicroRNAs in the Diagnosis and Treatment of Parkinson's Disease

Parkinson's disease (PD) is the second most common age-related neurodegenerative disorder after Alzheimer's disease. To date, the clinical diagnosis of PD is primarily based on the late onset of motor impairments. Unfortunately, at this stage, most of the dopaminergic neurons may have already been lost, leading to the limited clinical benefits of current therapeutics. Therefore, early identification of PD, especially at the prodromal stage, is still a main challenge in the diagnosis and management of this disease. Recently, microRNAs (miRNAs) in cerebrospinal fluid or peripheral blood have been proposed as putative biomarkers to assist in PD diagnosis and therapy. In this review, we systematically summarize the changes of miRNA expression profiles in PD patients, and highlight their putative roles in the diagnosis and treatment of this devastating disease.

Neurostimulation Devices for the Treatment of Neurologic Disorders

Rapid advancements in neurostimulation technologies are providing relief to an unprecedented number of patients affected by debilitating neurologic and psychiatric disorders. Neurostimulation therapies include invasive and noninvasive approaches that involve the application of electrical stimulation to drive neural function within a circuit. This review focuses on established invasive electrical stimulation systems used clinically to induce therapeutic neuromodulation of dysfunctional neural circuitry. These implantable neurostimulation systems target specific deep subcortical, cortical, spinal, cranial, and peripheral nerve structures to modulate neuronal activity, providing therapeutic effects for a myriad of neuropsychiatric disorders. Recent advances in neurotechnologies and neuroimaging, along with an increased understanding of neurocircuitry, are factors contributing to the rapid rise in the use of neurostimulation therapies to treat an increasingly wide range of neurologic and psychiatric disorders. Electrical stimulation technologies are evolving after remaining fairly stagnant for the past 30 years, moving toward potential closed-loop therapeutic control systems with the ability to deliver stimulation with higher spatial resolution to provide continuous customized neuromodulation for optimal clinical outcomes. Even so, there is still much to be learned about disease pathogenesis of these neurodegenerative and psychiatric disorders and the latent mechanisms of neurostimulation that provide therapeutic relief. This review provides an overview of the increasingly common stimulation systems, their clinical indications, and enabling technologies.

Dance is more than therapy: Qualitative analysis on therapeutic dancing classes for Parkinson's

OBJECTIVES

To understand the benefits and limitations of therapeutic dancing classes for people with Parkinson's disease (PD) and how best to design and implement classes.

DESIGN

A stakeholder forum explored the opinions of 18 allied health clinicians, dance instructors, people with PD and caregivers. Data were thematically analysed and interpreted within a grounded theory framework.

RESULTS

Four main themes were identified: (1) the need to consider the stage of disease progression when designing classes; (2) recognition that dance is more than just therapy; (3) the benefits of carefully selecting music to move by; (4) ways to design classes that are both feasible and engaging. These themes give rise to the theory that dancing classes can provide more than just therapeutic benefits. Dance affords creative expression and enables people to immerse themselves in the art-form, rather than focussing on the disease. The results highlight the benefits of enabling individuals with PD to be able to express themselves in a supportive environment that does not see them solely through the lens of Parkinson's. The feasibility of dance programs can be increased by educating dancing teachers about PD and the unique needs of people living with this condition.

CONCLUSION

Well-structured dance classes can promote social-connectedness and joy, in addition to facilitating movement to music and physical activity. Consumers advised that careful planning of the classes and tailoring them to participant needs optimizes outcomes.

Parkinson's Disease-Associated Mutant LRRK2-Mediated Inhibition of miRNA Activity is Antagonized by TRIM32

Parkinson’s disease (PD) is the second most common neurodegenerative disorder. Accumulating evidences suggest that PD might have a strong neurodevelopmental component. Among the genetic cases, mutations in the leucine-rich repeat kinase 2 (LRRK2) are well known to be disease causing. Although the molecular mechanism of the pathogenic LRRK2 function is not fully clear, inhibition of microRNA (miRNA) activity has been suggested to be among the pathogenic LRRK2 targets. Here, we demonstrate that the miRNA activity inhibition function of pathogenic LRRK2 is directly antagonized by the neuronal cell fate determinant TRIM32. These findings suggest that TRIM32 might be a modifier for PD and could be a novel therapeutic target.

Involvement of BDNF/TrkB signaling in the effect of diphenyl diselenide on motor function in a Parkinson's disease rat model

Parkinson's disease is a progressive neurodegenerative disorder characterized by degeneration of nigrostriatal dopaminergic neurons. Diphenyl diselenide [(PhSe)₂] is a compound with pharmacological proprieties, such as antidepressant and neuroprotective. Therefore, this study investigated whether (PhSe)₂ reverses motor impairment and neurochemical alterations in a model of Parkinson's disease induced by 6-hydroxydopamine (6-OHDA) in rats. For this, male Wistar rats received 20μg/3μl of 6-OHDA or vehicle into the right striatum. Three weeks later, animals were subjected to rotational behavioral test induced by D-amphetamine and randomly divided into four groups: Sham; (PhSe)₂; 6-OHDA and 6-OHDA+(PhSe)₂. The rats received (PhSe)₂ (1mg/kg/day; i.g.) or vehicle (canola oil) during 30 days. After treatment, behavioral tests were performed in order to evaluate the motor function and the ipsilateral striatal tissue was collected for immunoblotting assay. (PhSe)₂ treatment restored the normal motor behavior of 6-OHDA-infused rats in the cylinder, stepping and bridge tests, but not in the rotarod test. The 6-OHDA infusion and/or (PhSe)₂ treatment did not alter the muscle strength and spontaneous locomotion in the forelimb support and open-field tests, respectively. Additionally, striatal brain-derived neurotrophic factor (BDNF), proBDNF and tyrosine hydroxylase (TH) levels of 6-OHDA-lesioned rats were decreased, while the tropomyosin-related kinase B (TrkB) levels were increased. (PhSe)₂ treatment restored striatal proBDNF, TrkB and TH levels. Thus, (PhSe)₂ treatment reversed some motor impairment and TH levels in a 6-OHDA model of Parkinson's disease in rats, demonstrating a potential neurorestorative role. Additionally, the BDNF/TrkB signaling recovery can be involved in its neurorestorative effect.