Levodopa-induced Motor Complications Research Articles

A meta-analysis of the effectiveness and safety of safinamide for levodopa-induced motor complications in Parkinson’s disease

ABSTRACT To systematically evaluate the effectiveness and safety of safinamide in the treatment of levodopa-induced motor complications of Parkinson’s disease (PD). A search strategy was developed and PubMed, Embase, Web of Science, Cochrane Library, Chinese BioMedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI), and WanFang Data were searched to find randomized controlled trials on the treatment of PD motor complications caused by levodopa with safinamide. A manual reference search was conducted for articles published until June 2022 to independently screen references, extract data, and evaluate the risk of bias in the included studies. RevMan 5.3 software was utilized to analyze the data. A total of 5 randomized controlled trials with 2061 PD patients were included, containing 1277 patients in the safinamide group (trial group) and 784 patients in the control group. Meta-analysis results exhibited that regarding effectiveness, the duration of continuous optimal drug effect without dyskinesia (On-time) of the 50 mg trial group was longer than that of the control group. The On-time of the 100 mg trial group was longer than that of the control group.The improvement of the Unified Parkinson’s Disease Rating Scale Part III (UPDRSIII) score in the 50 mg trial group was better than that in the control group. The improvement of the UPDRSIII score of the 100 mg trial group was better than that of the control group.There was no significant difference in the incidence of adverse events between the two groups. Safinamide is effective and safe in the treatment of PD motor complications caused by levodopa.

Adverse effects of levodopa/carbidopa intrajejunal gel treatment: A single-center long-term follow-up study.

Levodopa/carbidopa intrajejunal gel (LCIG) is an effective therapeutic strategy to overcome levodopa-induced motor complications in advanced Parkinson's disease (PD). However, it requires invasive percutaneous endoscopic gastrojejunostomy (PEG-J) and may be associated with serious adverse effects (AE). In this study, we aimed to evaluate long-term AEs related to LCIG treatment in a large homogenous cohort of advanced PD patients. One hundred three consecutive PD patients were regularly monitored for LCIG-related, PEG-J-related, and device-related AEs up to 14 years. Incidence of AEs was studied in time applying a time-to-event analysis and Cox proportional hazard model with age, disease duration, gender, and recurrent AE as covariates. Health-related quality of life (HRQoL) was estimated at each visit and compared to HRQoL before the LCIG treatment. Among 296 AEs noted, 48.8% were LCIG-related, 32.4% PEG-J-related, and 19.6% device-related. While most of the studied AEs steadily accumulated throughout the follow-up period, 24.3% of the patients (95% CI 10.1%-36.3%) experienced PEG-J-related AE already within the first days after the PEG-J insertion. Cox model revealed that older patients had higher probability of psychosis, PEG-J- and device-related AEs (p < .05, p < .05, and p=.02) and suggested increased recurrence risk in those with early PEG-J and device-related AEs. Despite relatively high incidence of AEs, HRQoL significantly increased in the follow-up period (p < .0001). AEs related to LCIG treatment are common. Therefore, careful patient selection and monitoring throughout the treatment is recommended, especially in those with early side effects. Nevertheless, LCIG significantly improves HRQoL in advanced PD patients on a long term.

Continuous Dopaminergic Stimulation as a Treatment for Parkinson's Disease: Current Status and Future Opportunities

Levodopa-induced motor complications remain an important source of disability for many patients with Parkinson's disease. Substantial laboratory evidence indicates that motor complications relate to the nonphysiological restoration of brain dopamine with intermittent doses of standard oral levodopa. Dopamine levels are normally maintained at a relatively constant level, even following a dose of levodopa. However, in the Parkinsonian state, where dopamine terminals have degenerated with a loss of their buffering capacity, intermittent doses of levodopa lead to dramatic peak and trough fluctuations in striatal dopamine levels. This results in pulsatile stimulation of dopamine receptors, molecular changes in striatal neurons, physiological changes in pallidal neurons, and ultimately the development of motor complications. These observations led to the hypothesis that continuous delivery of levodopa might be associated with a reduced risk of motor complications. This concept is known as continuous dopamine stimulation (CDS). Preliminary studies in animal models and patients with Parkinson's disease supported this hypothesis, suggesting a reduced risk of both motor fluctuations and dyskinesias. The present review considers the scientific advances and the more definitive clinical trials testing this concept that have taken place during the past decade and considers ongoing experimental studies and future opportunities. © 2020 International Parkinson and Movement Disorder Society.

Characterization of Recessive Parkinson Disease in a Large Multicenter Study.

Studies of the phenotype and population distribution of rare genetic forms of parkinsonism are required, now that gene-targeting approaches for Parkinson disease have reached the clinical trial stage. We evaluated the frequencies of PRKN, PINK1, and DJ-1 mutations in a cohort of 1,587 cases. Mutations were found in 14.1% of patients; 27.6% were familial and 8% were isolated. PRKN was the gene most frequently mutated in Caucasians, whereas PINK1 mutations predominated in Arab-Berber individuals. Patients with PRKN mutations had an earlier age at onset, and less asymmetry, levodopa-induced motor complications, dysautonomia, and dementia than those without mutations. ANN NEUROL 2020;88:843-850.

Efficacy and safety of 5-Hydroxytryptophan on levodopa-induced motor complications in Parkinson's disease: A preliminary finding

Background and purposeSeveral studies have indicated that altered serotonergic neurotransmission may contribute to the motor features commonly associated with Parkinson's disease (PD) drug treatment such as levodopa-induced dyskinesias (LIDs). 5-Hydroxytryptophan (5-HTP) is the immediate precursor of serotonin. We have recently demonstrated that 5-HTP produces significant antidyskinetic effects in a rat model of PD. To date, there has been inconsistent research on the use of 5-HTP in PD. The purpose of this study was to compare the effects of 5-HTP versus placebo on levodopa-induced motor complications in PD patients. Material and methodsA single-center, randomized, double-blind placebo-controlled cross-over study was performed. A total of 12 PD patients were diagnosed with LIDs and motor fluctuactions and subsequently were randomized to intervention; 11 subjects completed the entire 16-week protocol. Patients received placebo or 50 mg of 5-HTP daily in a cross-over design over a period of 4 weeks. For the assessment of efficacy on the motor functions and motor complications, the UPDRS (parts III and IV), Unified Dyskinesia Rating Scale (UDysRS), Wearing-Off Questionnaire (WOQ-19) and the self-reported 24-h home dyskinesia diaries were obtained at baseline and weeks 4, 8, 12 and 16 (T-end). ResultsRepeated measures analysis revealed a significant improvement of LIDs during the 50 mg 5-HTP treatment as assessed by the UDysRS and UPDRS-IV scores. ConclusionsThis study provides preliminary evidence of clinical benefit of 5-HTP against LIDs in PD. Larger studies with a longer treatment duration and a wider range of doses are warranted to corroborate these findings.

Putaminal Dopamine Turnover in de novo Parkinson's Disease Predicts Later Neuropsychiatric Fluctuations but Not Other Major Health Outcomes.

To investigate the predictive value of striatal dopamine turnover in patients with de novo Parkinson's disease (PD) for later occurrence of major non-motor health outcomes. This retrospective, observer-blinded cohort study followed up 29 patients with de novo PD for a median of 10.7 years, who completed 18Fluorodopa PET imaging to measure striatal effective distribution volume ratio (EDVR, inverse of dopamine turnover) prior to antiparkinsonian treatment. Outcomes were assessed with a battery of non-motor, health-related quality-of-life and non-motor fluctuation (WOQ-19) measures and survival. During follow-up, 52% of patients developed wearing-off, 43% neuropsychiatric fluctuations, 35% sensory fluctuations, 32% dementia, 46% depression, 30% psychosis, and PD-related mortality was 26%. Patients with wearing-off and neuropsychiatric fluctuations showed significantly lower baseline EDVR (higher dopamine turnover) in the putamen but not in the caudate nucleus than those without these fluctuations. Consistently, baseline EDVR in the putamen predicted development of wearing-off and neuropsychiatric fluctuations with a lower risk with higher EDVR (lower dopamine turnover), whereas EDVR in caudate nucleus did not correlate with these fluctuations. No relationships were observed between baseline PET measures and the presence of other major health outcomes including survival. Lower putaminal dopamine turnover in de novo PD is associated with reduced risk for later neuropsychiatric fluctuations comprising a disease-intrinsic predisposing factor for their development, similar as reported for levodopa-induced motor complications. Striatal (putaminal/caudate) dopamine turnover is not predictive for other long-term major health outcomes. These results should be treated as hypothesis generating and require confirmation.

Genetic and Phenotypic Characterisation of Autosomal Recessive Parkinson's Disease in a Large Multicentre Cohort

Background: Genetic mutations causing autosomal recessive Parkinson's disease account for a significant proportion of patients with early-onset disease. However, no large multicentre studies of known recessive Parkinson's disease-linked genes have been performed, to guide genetic testing according to age at onset, family history, ethnic origin, or phenotype. We aimed to evaluate the relative frequencies of mutations in genes causing recessive Parkinson's disease and their associated phenotypes in a large series of European and North African cases. Methods: Clinical data for 1664 patients were collected between 1990 and 2018 from 511 families with recessive Parkinson's disease and/or with consanguinity, and 1098 isolated cases. All the recessively inherited genes were screened by Sanger and/or targeted next-generation sequencing and gene dosage methods. Clinical features were compared between patients with PRKN and those without mutations, by regression analyses adjusted for sex, age at onset, disease duration and levodopa medication. Findings: Biallelic mutations of genes known to cause recessive Parkinson's disease were found in 246 of the 1609 index cases (15·3%): 150 familial (29·4%) and 96 (8·7%) isolated cases. The most frequently mutated genes were PRKN, in 199 cases (12·4%), PINK1, in 23 (1·8%), and DJ-1, in two (0·16%). We screened 675 index cases by targeted sequencing, and 22 were found to have mutations in genes known to cause atypical parkinsonism (3·3%). PRKN and PINK1 mutation frequencies were higher in early-onset (≤40 years) than late-onset Parkinson's disease. The frequency of PRKN mutations in the 1609 index cases decreased with increasing age at onset, from 38% in cases ≤20 years to 4·4% in those with onset at 41 to 60 years. No mutation of PRKN or another recessive Parkinson's disease gene was found in patients with onset above 60. PRKN mutations were more frequent in Caucasians (13·4%) than in North Africans (7·4%). Conversely, PINK1 mutations were more frequent in North Africans (6·3%) than in Caucasians (0·9%). PRKN patients had an earlier age at onset, lower levels of asymmetry, akinesia, levodopa-induced motor complications, dysautonomia, and dementia than those without mutations. Interpretation: This is a large study providing information about the frequency of recessive Parkinson's disease genes according to age at onset, family history, ethnic origin, and associated phenotype. Its findings will be useful for genetic testing and counselling. Funding Statement: Fondation de France, France-Parkinson Association, la Federation pour la Recherche sur le Cerveau, the French program Investissements d'avenir, National Institute for Health Research. Declaration of Interests: SL reports grants from Fondation de France, the French program “Investissements d’avenir” (ANR-10-IAIHU-06), both outside the scope of the submitted work. MA reports grants and personal fees from Abbvie, Teva, Aguettant, Actelion Pharmaceuticals, personal fees from Johnson and Johnson, Merz, Orkyn, all outside the scope of the submitted work. ER reports grants, personal fees and non-financial support from Orkyn, Aguettant, Merz pharma, Everpharma, personal fees and non-financial support from Movement Disorders Society, grants and non-financial support from Elivie, non-financial support from Merck, Dystonia Coalition, Dystonia Medical Research Foundation, grants from Ipsen, Fondation Desmarest, Fonds de dotation Brou de Lauriere, Agence Nationale de la Recherche, AMADYS, personal fees from Medday pharma, Retrophin, European Academy of Neurology, International Association of Parkinsonism and related Disorders, all outside the submitted work. CT received fees from ALLERGAN and from MERZ. J-CC reports grants from Sanofi, personal fees from EverPharma, Denali, BrainEver, Theranexus, Air Liquide, all outside the scope of this work. EB reports grants from Medtronic France, Abbvie, UCB, and Aguettant laboratories but no conflict of interest nor financial concerns about the present research paper submitted for publication. AB reports grants from ANR - Agence nationale de recherche, ARNN - Association pour la Recherche en Neuro-imagerie et Neuropsychologie, France Parkinson, AP-HP, FMR - Fondation Maladies Rares (ex GIS), France Parkinson + FRC (Federation pour la Recherche sur le Cerveau), Universite Mohammed V - Rabat, Prix Allianz Institut de France, RDS (Roger de Spoelberch Foundation), FDF -Fondation de France-, all outside the submitted work. All other authors have no competing interests to declare. Ethics Approval Statement: Informed consent was obtained from all participants, and genetic studies were approved by local ethics committees (INSERM, CCPPRB du Groupe Hospitalier Pitie-Salpetriere, Paris, France).

Stimulation of the globus pallidus internus in the treatment of Parkinson's disease: Long-term results of a monocentric cohort

BackgroundPallidal deep brain stimulation (DBS) has shown to be beneficial in patients with advanced levodopa-responsive Parkinson's disease (PD) in several short-term studies. However, reported long-term outcomes of pallidal DBS for PD are limited and contradictory. MethodsEighteen consecutive PD patients were treated with unilateral or bilateral stimulation of the internal part of the globus pallidus (GPi). Assessments were carried out before and six months after neurosurgery, and annually thereafter for up to 16 years (mean follow-up time: 6 years). Primary outcomes included motor signs (Unified PD Rating Scale [UPDRS]-III), activities of daily living (ADL, UPDRS-II), and levodopa-induced motor complications (UPDRS-IV). ResultsThe results show that GPi stimulation improves levodopa-responsive PD motor signs (UPDRS-III), levodopa-induced motor complications (UPDRS-IV), and ADL (UPDRS-II) in advanced PD. Among motor signs, tremor showed the best response to pallidal stimulation. Levodopa-induced motor complications and tremor showed improvements for more than 10 years after neurosurgery. ConclusionsThe overall findings in our cohort demonstrate that pallidal stimulation is effective in reducing parkinsonian motor signs (UPDRS-III), particularly in the ‘off’-medication state. Although the beneficial effects on bradykinesia, rigidity and ADL may be limited to 5–6 years, the follow up results indicate that the improvements of levodopa-induced motor complications (UPDRS-IV) and tremor can be sustained for more than 10 years.

Dysphagia predicts poor outcome in late-stage Parkinson's disease

BackgroundFew data exist on the rate of clinical progression for Parkinson's disease (PD) patients who have entered a late stage of the disease. ObjectiveStudy the clinical progression of a late-stage PD (LSPD) population over one year follow-up. Methods50 LSPD patients (Schwab and England ADL Scale <50 or Hoehn Yahr Stage >3 in MED ON) underwent an extensive clinical assessment at baseline and after one year and an acute levodopa test at baseline. ResultsMean age of LSPD patients (female 46%) was 77.5 ± 5.9 years and mean disease duration was 15.5 ± 6.5 years. At baseline, 76% had levodopa-induced motor complications (MC), usually non-troublesome, 68% were demented, 54% had psychosis and 68% depression. Caregiver distress was high. l-dopa responsiveness was mild (18% ± 12 of improvement on MDS-UPDRS-III). After one-year, 20% of the patients were dead, institutionalized or HY 5. MDS-UPDRS-motor mean score worsened 7.2 ± 10.3 points although there was heterogeneity between patients, and there was a global worsening of non-motor symptoms, mostly in cognition/mood, urinary and gastrointestinal domains. Nevertheless, MC improved despite similar levodopa equivalent dose. Functional independence and quality of life worsened. Dysphagia severity at baseline predicted a poor outcome (death, institutionalization or HY 5) (Hazard ratio 2.3, 95% CI 1.12–4.4; p = 0.01), whereas magnitude of l-dopa response of LSPD patients did not. ConclusionsLSPD patients still present a significant, although heterogeneous, motor and non-motor progression over 1 year. Dysphagia severity predicts the occurrence of additional disease severity milestones and its management must be prioritized.

Levodopa-induced motor complications in Vietnamese patients with Parkinson’s disease

levodopa-induced motor complications in Vietnamese patients with Parkinson’s disease

Diabetes mellitus accelerates the onset of levodopa-related motor complications and leads to lower MoCA scores in patients with mild to moderate Parkinsons disease

Recent evidence suggests that diabetes mellitus (DM) may increase the risk of developing Parkinson’s disease (PD) and predisposes to more severe cognitive disturbances amongst PD patients. However, the effects of DM on levodopa-induced motor complications and other non-motor complications are not well studied.

The prevalence of levodopa induced motor complications and the associated factors in Parkinson disease patients: Study in a Japanese single center for movement disorder

The prevalence of levodopa induced motor complications and the associated factors in Parkinson disease patients: Study in a Japanese single center for movement disorder

Stratifying Parkinson’s Patients With STN-DBS Into High-Frequency or 60 Hz-Frequency Modulation Using a Computational Model

High frequency stimulation (HFS) of the subthalamic nucleus (STN) is a well-established therapy for Parkinson's disease (PD), particularly the cardinal motor symptoms and levodopa induced motor complications. Recent studies have suggested the possible role of 60 Hz stimulation in STN-deep brain stimulation (DBS) for patients with gait disorder. The objective of this study was to develop a computational model, which stratifies patients a priori based on symptomatology into different frequency settings (i.e., high frequency or 60 Hz). We retrospectively analyzed preoperative MDS-Unified Parkinson's Disease Rating Scale III scores (32 indicators) collected from 20 PD patients implanted with STN-DBS at Mount Sinai Medical Center on either 60 Hz stimulation (ten patients) or HFS (130-185 Hz) (ten patients) for an average of 12 months. Predictive models using the Random Forest classification algorithm were built to associate patient/disease characteristics at surgery to the stimulation frequency. These models were evaluated objectively using leave-one-out cross-validation approach. The computational models produced, stratified patients into 60 Hz or HFS (130-185 Hz) with 95% accuracy. The best models relied on two or three predictors out of the 32 analyzed for classification. Across all predictors, gait and rest tremor of the right hand were consistently the most important. Computational models were developed using preoperative clinical indicators in PD patients treated with STN-DBS. These models were able to accurately stratify PD patients into 60 Hz stimulation or HFS (130-185 Hz) groups a priori, offering a unique potential to enhance the utilization of this therapy based on clinical subtypes.

Disability in Activities of Daily Living andSeverity of Dyskinesias Determine theHandicap of Parkinson's Disease Patients inAdvanced Stage Selected to DBS.

There is scarce data on the level of handicap in Parkinson's disease (PD) and none in advanced stage PD. To assess the handicap in advanced stage PD patients with disabling levodopa-induced motor complications selected to deep brain stimulation (DBS). Data was prospectively recorded during routine evaluation for DBS. Handicap was measured using London Handicap Scale (LHS) (0 = maximal handicap; 1 = no handicap). Disease severity was evaluated using the Hoehn & Yahr scale and the UPDRS/MDS-UPDRS, during off and on after a supra-maximal dose of levodopa. Schwab and England Scale (S&E) was scored in off and on. Dyskinesias were scored using the modified Abnormal Involuntary Movement Scale (mAIMS). Results concern cross-sectional assessment before DBS. 100 PD patients (mean age 61 (±7.6); mean disease duration 12.20 (±4.6) years) were included. Median score of motor MDS-UPDRS was 54 in off and 25 in on. Mean total LHS score was 0.56 (±0.14). Patients were handicapped in several domains with a wide range of severity. Physical Independence and Social Integration were the most affected domains. Determinants of total LHS score were MDS-UPDRS part II off (β= -0.271; p = 0.020), S&E on (β= 0.264; p = 0.005) and off (β= 0.226; p = 0.020), and mAIMS on (β= -0.183; p = 0.042) scores (R2 = 29.6%). We were able to use handicap to measure overall health condition in advanced stage PD. Patients were moderately to highly handicapped and this was strongly determined by disability in ADL and dyskinesias. Change in handicap may be a good patient-centred outcome to assess efficiency of DBS.

Parkinson's disease associated with 22q11.2 deletion: Clinical characteristics and response to treatment

BackgroundWhile it is known that 22q11.2 microdeletions (22q11.2-del) increase the risk of Parkinson's disease (PD), the characteristics of PD associated with 22q11.2-del have not been specifically explored. ObjectiveThis report aimed to assess the clinical characteristics and treatment responses of PD patients with 22q11.2-del, and to describe any features that might lead neurologists to investigate the comorbidity. MethodsNine PD patients (eight men, one woman) with 22q11.2-del were followed at seven centers of the French PD Expert Network (Ns-Park). ResultsPD diagnosis was made before 22q11.2-del diagnosis in seven cases; their main characteristics were early onset (32–48 years) and good initial levodopa sensitivity, but with a course characterized by severe and early-onset levodopa-induced motor complications and psychiatric manifestations. Three patients received deep brain stimulation (DBS) that was effective. ConclusionSearching for 22q11.2-del in PD patients presenting with suggestive features is relevant as the clinical presentation is similar to idiopathic PD, but with other associated characteristics, including a severe evolution. Results with DBS are similar to those reported for idiopathic PD.

Parkinson's Disease and development of levodopa induced motor complications: Influence of baseline features and first medical approach

BackgroundThe introduction of levodopa in clinical practice represents a hallmark in the treatment of the neurodegenerative disease, Parkinson's Disease. However, levodopa induced motor complications, namely dyskinesias and motor fluctuations, develop in the majority of Parkinson's Disease patients. Objectiveto identify which Parkinson's Disease's, patient's and therapeutics’ initial features are more associated with dyskinesias or motor fluctuations development. MethodsPatients with diagnosed Parkinson's Disease attending neurology outpatient clinic at Centro Hospitalar São João were selected. For this observational study, data was retrospectively collected from patient's clinical records. A survival analysis model with univariate and multivariate regression analysis was used. Results87 patients with a mean of 72±9.7 years were included. After a median follow-up of 6 (range 1–17) years, 35.6% patients developed dyskinesias; and with a median of 5 (range 1–16) years, 32.2% developed motor fluctuations. After multivariate analysis, the akinesia/rigidity subtype was found to have a higher risk of dyskinesias and motor fluctuations development. Age of onset ≤50 years was associated with motor fluctuations development. ConclusionIn conclusion, our results suggest that Parkinson's Disease patients’ initial characteristics, such as subtype or age of onset, are independently associated with the development of motor complications.

Piribedil for the Treatment of Motor and Non-motor Symptoms of Parkinson Disease.

Dopamine agonists are well-established symptomatic medications for treating early and advanced Parkinson disease (PD). Piribedil was one of the first agonists to be marketed (1969) and is widely used as an extended-release oral formulation in European, Latin-American, and Asian countries. Piribedil acts as a non-ergot partial dopamine D2/D3-selective agonist, blocks alpha2-adrenoreceptors and has minimal effects on serotoninergic, cholinergic, and histaminergic receptors. Animal models support the efficacy of piribedil to improve parkinsonian motor symptoms with a lower propensity than levodopa to induce dyskinesia. In PD patients, randomized double-blind studies show that piribedil (150-300mg/day, three times daily) is superior to placebo in improving motor disability in early PD patients. Based on such evidence, piribedil was considered in the last Movement Disorder Society Evidence-Based Medicine review as "efficacious" and "clinically useful" for the symptomatic treatment of PD, either as monotherapy or in conjunction with levodopa, in non-fluctuating early PD patients. This effect appears comparable to what is known from other D2 agonists. However, randomized controlled trials are not available to assess the effect of piribedil in managing levodopa-induced motor complications. Pilot clinical studies suggest that piribedil may improve non-motor symptoms, such as apathy, but confirmatory trials are needed. The tolerability and safety profile of piribedil fits with that of the class of dopaminergic agonists. As for other non-ergot agonists, pneumo-pulmonary, retroperitoneal, and valvular fibrotic side effects are not a concern with piribedil. The original combination of piribedil D2 dopaminergic and alpha-2 adrenergic properties deserve further investigations to better understand its antiparkinsonian profile.

Current Pharmaceutical Treatments and Alternative Therapies of Parkinson's Disease.

Over the decades, pharmaceutical treatments, particularly dopaminergic (DAergic) drugs have been considered as the main therapy against motor symptoms of Parkinson's disease (PD). It is proposed that DAergic drugs in combination with other medications, such as monoamine oxidase type B inhibitors, catechol-O-methyl transferase inhibitors, anticholinergics and other newly developed non-DAergic drugs can make a better control of motor symptoms or alleviate levodopa-induced motor complications. Moreover, non-motor symptoms of PD, such as cognitive, neuropsychiatric, sleep, autonomic and sensory disturbances caused by intrinsic PD pathology or drug-induced side effects, are gaining increasing attention and urgently need to be taken care of due to their impact on quality of life. Currently, neuroprotective therapies have been investigated extensively in pre-clinical studies, and some of them have been subjected to clinical trials. Furthermore, non-pharmaceutical treatments, including deep brain stimulation (DBS), gene therapy, cell replacement therapy and some complementary managements, such as Tai chi, Yoga, traditional herbs and molecular targeted therapies have also been considered as effective alternative therapies to classical pharmaceutics. This review will provide us updated information regarding the current drugs and non-drugs therapies for PD.

Advanced Parkinson disease patients have impairment in prosody processing

ABSTRACTBackground: The ability to recognize and interpret emotions in others is a crucial prerequisite of adequate social behavior. Impairments in emotion processing have been reported from the early stages of Parkinson’s disease (PD). This study aims to characterize emotion recognition in advanced Parkinson’s disease (APD) candidates for deep-brain stimulation and to compare emotion recognition abilities in visual and auditory domains. Method: APD patients, defined as those with levodopa-induced motor complications (N = 42), and healthy controls (N = 43) matched by gender, age, and educational level, undertook the Comprehensive Affect Testing System (CATS), a battery that evaluates recognition of seven basic emotions (happiness, sadness, anger, fear, surprise, disgust, and neutral) on facial expressions and four emotions on prosody (happiness, sadness, anger, and fear). APD patients were assessed during the “ON” state. Group performance was compared with independent-samples t tests. Results: Compared to controls, APD had significantly lower scores on the discrimination and naming of emotions in prosody, and visual discrimination of neutral faces, but no significant differences in visual emotional tasks. Conclusion: The contrasting performance in emotional processing between visual and auditory stimuli suggests that APD candidates for surgery have either a selective difficulty in recognizing emotions in prosody or a general defect in prosody processing. Studies investigating early-stage PD, and the effect of subcortical lesions in prosody processing, favor the latter interpretation. Further research is needed to understand these deficits in emotional prosody recognition and their possible contribution to later behavioral or neuropsychiatric manifestations of PD.

Contribution of brain serotonin subtype 1B receptors in levodopa-induced motor complications

l-DOPA-induced dyskinesias (LID) are abnormal involuntary movements limiting the chronic use of l-DOPA, the main pharmacological treatment of Parkinson's disease. Serotonin receptors are implicated in the development of LID and modulation of basal ganglia 5-HT1B receptors is a potential therapeutic alternative in Parkinson's disease. In the present study, we used receptor-binding autoradiography of the 5-HT1B-selective radioligand [3H]GR125743 to investigate possible contributions of changes in ligand binding of this receptor in LID in post-mortem brain specimens from Parkinson's disease patients (n = 14) and control subjects (n = 11), and from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned monkeys treated with saline (n = 5), l-DOPA (n = 4) or l-DOPA + 2-methyl-6-(phenylethynyl)pyridine (MPEP) (n = 5), and control monkeys (n = 4). MPEP is the prototypal metabotropic glutamate 5 (mGlu5) receptor antagonist and has been shown to reduce the development of LID in these monkeys in a chronic treatment of one month. [3H]GR125743 specific binding to striatal and pallidal 5-HT1B receptors respectively were only increased in l-DOPA-treated MPTP monkeys (dyskinetic monkeys) as compared to controls, saline and L-DOPA + MPEP MPTP monkeys; dyskinesias scores correlated positively with this binding. Parkinson's disease patients with motor complications (l-DOPA-induced dyskinesias and wearing-off) had higher [3H]GR125743 specific binding compared to those without motor complications and controls in the basal ganglia. Reduction of motor complications was associated with normal striatal 5-HT1B receptors, suggesting the potential of this receptor for the management of motor complications in Parkinson's disease.