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Background The objective of this study was to assess the effect of rotigotine treatment on bladder function in patients with Parkinson's disease ( PD) who have urinary urgency. Methods in total, 20 patients with PD underwent urodynamic evaluation and completed International Prostate Symptoms questionnaires in off-rotigotine condition and after 3 months of rotigotine patch monotherapy administration. In both sessions, clinical motor condition was evaluated with the Unified Parkinson Disease Rating Scale, Part III (motor part). Results Rotigotine administration significantly ameliorated the first sensation of bladder filling, the neurogenic detrusor overactive contractions threshold and bladder capacity compared with the off-treatment condition. Moreover, the total score on the International Prostate Symptoms questionnaire revealed a decrease of filling (irritative) symptoms after rotigotine treatment compared with the off-treatment condition. Conclusion The positive effects of rotigotine may be due to its balanced agonism to D1 and D2 receptors and in particular to its stimulation of D1 receptors in the anterior cingulate cortex and insula, which are known as areas involved in bladder-inhibitory functions. [ABSTRACT FROM AUTHOR]

Objectives: A mutation in leucine-rich repeat kinase 2 is the most common cause of hereditary Parkinson's disease (PD), yet the neural mechanisms and the circuitry potentially involved are poorly understood.Methods: We used different transcranial magnetic stimulation protocols to explore in the primary motor cortex the activity of intracortical circuits and cortical plasticity (long-term potentiation) in patients with the G2019S leucine-rich repeat kinase 2 gene mutation when compared with idiopathic PD patients and age-matched healthy subjects. Paired pulse transcranial magnetic stimulation was used to investigate short intracortical inhibition and facilitation and short afferent inhibition. Intermittent theta burst stimulation, a form of repetitive transcranial magnetic stimulation, was used to test long-term potentiation-like cortical plasticity. Leucine-rich repeat kinase 2 and idiopathic PD were tested both in ON and in OFF l-dopa therapy.Results: When compared with idiopathic PD and healthy subjects, leucine-rich repeat kinase 2 PD patients showed a remarkable reduction of short intracortical inhibition in both ON and in OFF l-dopa therapy. This reduction was paralleled by an increase of intracortical facilitation in OFF l-dopa therapy. Leucine-rich repeat kinase 2 PD showed abnormal long-term potentiation-like cortical plasticity in ON l-dopa therapy.Discussion: The motor cortex in leucine-rich repeat kinase 2 mutated PD patients is strongly disinhibited and hyperexcitable. These abnormalities could be a result of an impairment of inhibitory (gamma-Aminobutyric acid) transmission eventually related to altered neurotransmitter release. © 2017 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Background: Levodopa-induced dyskinesias are associated with thalamo-cortical disinhibition and frontal area overactivation. Neuroimaging and transcranial magnetic stimulation studies have highlighted the involvement of the right inferior frontal cortex in levodopa-induced dyskinesias.Methods: Using transcranial magnetic stimulation, we tested connectivity between the inferior frontal and contralateral motor cortex in Parkinson's disease patients with and without levodopa-induced dyskinesias compared with age-matched controls. Furthermore, in dyskinetic patients, connectivity between the inferior frontal and contralateral motor cortex was assessed before and after a single session of continuous theta-burst stimulation applied over the inferior frontal cortex.Results: Dyskinetic patients showed abnormal facilitatory connectivity between the inferior frontal and motor cortex when compared with the nondyskinetic group. Continuous theta-burst stimulation over the inferior frontal cortex eliminated such facilitatory connectivity and decreased the levodopa-induced dyskinesias that was induced by a supramaximal dose of levodopa.Conclusion: In dyskinetic patients, a weaker inhibitory cortico-cortical interaction between the inferior frontal and contralateral motor cortex could be involved in levodopa-induced dyskinesias and restored by continuous theta-burst stimulation over the inferior frontal cortex. © 2016 Movement Disorder Society. [ABSTRACT FROM AUTHOR]

The pathophysiological mechanisms of levodopa-induced dyskinesias (LIDs) in Parkinson’s disease are a matter of debate. Combining functional neuroimaging and repetitive TMS, Cerasa et al. provide evidence that LIDs result from reduced inhibitory control mediated by inferior frontal cortex. The findings open up new possibilities for the development of therapeutic tools.See Rothwell and Obeso (doi:10.1093/brain/awu365) for a scientific commentary on this article.Levodopa-induced dyskinesias are disabling motor complications of long-term dopamine replacement in patients with Parkinson’s disease. In recent years, several alternative models have been proposed to explain the pathophysiological mechanisms underlying this hyperkinetic motor disorder. In particular, our group has shed new light on the role of the prefrontal cortex as a key site of interest, demonstrating that, among other areas, the inferior frontal cortex is particularly characterized by altered patterns of anatomical and functional changes. However, how neural activity varies depending on levodopa treatment in patients with dyskinesias and whether the reported prefrontal abnormalities may have a critical role in dyskinesias is debated. To answer these questions we performed independent functional magnetic resonance imaging and repetitive transcranial magnetic stimulation studies. In the first experiment we applied resting state functional magnetic resonance imaging on 12 patients with Parkinson’s disease with levodopa-induced dyskinesias and 12 clinically matched patients without dyskinesias, before and after administration of levodopa. Functional connectivity of brain networks in the resting state was assessed in both groups. We chose the right inferior frontal cortex as the seed region given the evidence highlighting the role of this region in motor control. In a second experiment, we applied different forms of repetitive transcranial magnetic stimulation over the right inferior frontal cortex in a new group of dyskinetic patients who were taking a supramaximal dose of levodopa, to verify the clinical relevance of this area in controlling the development of hyperkinetic movements. The resting state functional imaging analysis revealed that in patients with levodopa-induced dyskinesias connectivity of the right inferior frontal cortex was decreased with the left motor cortex and increased with the right putamen when compared to patients without levodopa-induced dyskinesias. This abnormal pattern of connectivity was evident only during the ON phase of levodopa treatment and the degree of such alteration correlated with motor disability. The repetitive TMS experiments showed that a session of continuous but not intermittent or sham theta burst stimulation applied over the inferior frontal cortex was able to reduce the amount of dyskinesias induced by a supramaximal single dose of levodopa, suggesting that this area may play a key role in controlling the development of dyskinesias. Our combined resting state functional magnetic resonance and transcranial magnetic stimulation studies demonstrate that pathophysiological mechanisms underlying levodopa-induced dyskinesias may extend beyond the ‘classical’ basal ganglia dysfunctions model, including the modulation performed by the neural network centred on the inferior frontal cortex. [ABSTRACT FROM AUTHOR]

Bladder dysfunction may cause disabling symptoms in Parkinson's disease (PD) patients. The majority patients' experience symptoms as urinary urgency and nocturia suggest overactive bladder. This seems to be due to an altered brain–bladder relationship because of alteration in fronto-basal ganglia D1-dopaminergic circuit that normally suppresses micturition-reflex. Previous studies demonstrated beneficial effect of D1/D2 dopamine-receptors chronic-stimulation on detrusor overactivity of PD-patients.The present study was aimed to evaluate possible effect of extended-release (ER) Levodopa administered at bed-time on both nocturia and nocturia-related quality-of-life (NQoL) in PD-patients. 106 PD-patients (Hoehn and Yahr>1 and < 4, mean age 66 years, 59 females and 47 males) were enrolled by 7 Movement Disorders out-patients clinics. Patients undergo to International Prostatic Symptoms Scale-IPSS, including 1-item about nocturia (item 7), and to Nocturia Quality of Life-NQoL questionnaire, at baseline and after two-months of Extended-Release L-dopa (L-dopa/carbidopa or L-dopa benserazide) treatment at bed-time. Statistical analysis showed significant improvement on both total IPSS, item 7and NQoL scores following two-months ER L-dopa-treatment. ΔIPSS score inversely correlated with disease duration. This results support previous evidence of pathophysiological involvement of dopaminergic transmission on bladder dysfunction in PD. • Overactive bladder is the most common symptoms in PD patients. • Overactive bladder depends on altered D1dopaminergic circuit. • Extended-release L-dopa administration improves bladder dysfunction in PD patients. [ABSTRACT FROM AUTHOR]

Introduction: Patients with Scans-Without-Evidence-of-Dopaminergic-Deficit (SWEDD) often present asymmetric rest tremor not responsive to levodopa. Although a dystonic origin of this tremor has been proposed, the underlying pathophysiology of such condition is still unclear. An abnormal activity in the Cerebello-Thalamo-Cortical circuit is involved in the pathogenesis of tremor and other movement disorders. Here we used different paradigms of cerebellar transcranial magnetic stimulation to evaluate the Cerebello-Thalamo-Cortical functioning in patients with normal scans.Methods: Cerebello-Thalamo-Cortical circuit was investigated in 12 patients with normal scans, 8 patients with Parkinson's Disease (PD), 8 patients with adult-onset isolated dystonia and 9 healthy controls. We studied the effects of a single cerebellar magnetic pulse over the excitability of the contralateral primary motor cortex tested with Motor-Evoked-Potentials (Cerebellar-Inhibition) both at rest and during arm extension. Furthermore, we also tested the effects of cerebellar continuous-Theta-Burst-Stimulation on Motor-Evoked-Potentials amplitude.Results: patients with normal scans compared to controls show a deficient Cerebellar-Inhibition at rest but not in arm extension; in both conditions they differ from PD but not from dystonic patients. Cerebellar Continuous-Theta-Burst-Stimulation induced the expected long-lasting cortical inhibition of Motor-Evoked-Potentials amplitude in patients with normal scans differently from PD and dystonic patients.Conclusions: patients with normal scans show a mild impairment in Cerebello-Thalamo-Cortical circuit that emerges only at rest. Such neurophysiological phenotype differs from the one observed in PD and dystonic patients, suggesting a distinct involvement of this pathway in the pathophysiology of these disorders. [ABSTRACT FROM AUTHOR]

Background: The effects of deep brain stimulation of the subthalamic nucleus (DBS-STN) and L-dopa (LD) on cortical activity in Parkinson's disease (PD) are poorly understood.Objectives: By combining transcranial magnetic stimulation (TMS) and electroencephalography (EEG) we explored the effects of STN-DBS, either alone or in combination with L-Dopa (LD), on TMS-evoked cortical activity in a sample of implanted PD patients.Methods: PD patients were tested in three clinical conditions: i) LD therapy with STN-DBS turned on (ON/ON condition); ii) without LD therapy with STN-DBS turned on (OFF/ON condition); iii) without LD therapy with STN-DBS turned off (OFF/OFF condition). TMS pulses were delivered over left M1 while simultaneously acquiring EEG. Eight age-matched healthy volunteers (HC) were tested as a control group.Results: STN-DBS enhanced early global TMS-evoked activity (∼45-80ms) and high-alpha TMS-evoked oscillations (11-13 Hz) as compared to OFF/OFF condition, independently from concomitant LD therapy. LD intake (ON/ON condition) produced a further increase of late TMS-evoked activity (∼80-130ms) and beta TMS-evoked oscillations (13-30 Hz), as compared to OFF/OFF and OFF/ON conditions, that normalized reactivity as compared to HC range of values.Conclusions: Our data reveal that bilateral STN-DBS and LD therapy induce a modulation of specific cortical components and specific ranges of frequency. These findings demonstrate that STN-DBS and LD therapy may have synergistic effects on motor cortical activity. [ABSTRACT FROM AUTHOR]