Signs of early cellular dysfunction in multiple system atrophy.

AIMS: Multiple system atrophy (MSA) is a fatal neurodegenerative disease that belongs to the family of α-synucleinopathies. At post mortem examination, intracellular inclusions of misfolded α-synuclein are found in neurons and oligodendrocytes and are considered to play a significant role in the pathogenesis. However, the early steps of the disease process are unknown and difficult to study in tissue derived from end-stage disease. METHODS: Induced pluripotent stem cells (iPSCs) were generated from patients' and control skin fibroblasts and differentiated into NCAM-positive neural progenitor cells (NPCs). The mitochondrial morphology and function were assessed by immunocytochemistry and high resolution respirometry. The ability to cope with exogenous oxidative stress was tested by exposure to different doses of luperox. The expression of α-synuclein was studied by immunocytochemistry. RESULTS: We identified increased tubulation of mitochondria with preserved respiration profile in MSA-derived NPCs. Exposure of these cells to exogenous oxidative stress even at low doses, triggered an excessive generation of reactive oxygen species (ROS) and cleavage of caspase-3. MSA-derived NPCs did not present changed levels of SNCA gene expression nor intracellular aggregates of α-synuclein. However, we identified disease-related translocation of α-synuclein to the nucleus. CONCLUSIONS: Our results show early cellular dysfunction in MSA-derived NPCs. We identified changes in the redox homeostasis which are functionally compensated at baseline but cause increased susceptibility to exogenous oxidative stress. In addition, nuclear translocation of α-synuclein in MSA-derived NPCs supports an early cellular stress response which may precede the neurodegenerative process in this disorder.

Development of neurodegeneration in amyotrophic lateral sclerosis: from up or down?

Amyotrophic lateral sclerosis (ALS) is a fatal neurological disease associated with neurodegeneration and intracellular pathological 43-kDa transactive response sequence DNA-binding protein (TDP-43) positive inclusions. The various clinical symptoms, such as motor disorders and cognitive impairment, reflect the degeneration of certain areas of the nervous system. Since the discovery of the significance of pathological TDP-43 for human disease including ALS, there has been an increasing number of studies reporting on the distribution and severity of neurodegeneration. These have rekindled the old debate about whether the first or second motor neuron is the primary site of degeneration in ALS. To shed light on this question, the following is a review of the relevant neuropathological studies.

Key themes and future prospects in translational multiple system atrophy research.

Multiple system atrophy (MSA) is a rapidly progressive neurodegenerative disorder with a highly variable clinical presentation. Unfortunately, there exists no effective therapy that can improve the course of the disease and symptomatic treatment options remain limited. Although significant progress in research has improved our understanding of MSA, knowledge gaps still remain. Thus, a global network focusing on different research areas is required to face this fatal disease.

Sniffing the diagnosis: Olfactory testing in neurodegenerative parkinsonism.

OBJECTIVE: To determine the diagnostic utility of olfactory testing in patients with neurodegenerative parkinsonism. METHODS: The Sniffin' Sticks test battery for assessment of odor identification, discrimination, and threshold was applied to patients with Parkinson's disease (PD), multiple system atrophy (MSA) and progressive supranuclear palsy (PSP) as well as healthy controls (HC). Two different cohorts were analyzed: A PD/healthy control that included PD patients and HC as well as a PD/diseased control cohort for which patients PD, MSA and PSP were recruited. The former cohort was exploited to calculate cut-off values that discriminate PD patients from HC with a sensitivity (sensitivity-weighted cut-off) or specificity (specificity-weighted cut-off) exceeding 95%, respectively. The PD/diseased controls cohort was used to determine the diagnostic accuracy using these cut-off values in discriminating patients with neurodegenerative parkinsonism. RESULTS: PD patients (n = 67) performed significantly worse in olfactory testing than HC (n = 41) and patients with MSA (n = 23) or PSP (n = 23). There was no significant difference in olfactory function between MSA and PSP patients. Diagnostic performance of the identification subscore was similar to the sum score of the Sniffin' Sticks test (AUC identification test 0.94, AUC sum score 0.96), while threshold and discrimination subscores were inferior. In patients with parkinsonism, the specificity-weighted cut-off predicted a diagnosis of PD with a sensitivity and specificity of 76.6 and 87.0%, respectively. The discriminative value of this cut-off in separating PD from MSA was 76.7% (sensitivity) and 95.7% (specificity). The corresponding, prevalence-adjusted positive predictive value of olfactory testing exceeded 95%. CONCLUSIONS: Our data suggest that assessment of olfactory function, particularly odor identification, can be useful to discriminate PD from atypical parkinsonian disorders, particularly MSA patients.

Review: Multiple system atrophy: emerging targets for interventional therapies.

Multiple system atrophy (MSA) is a fatal orphan neurodegenerative disorder that manifests with rapidly progressive autonomic and motor dysfunction. The disease is characterized by the accumulation of α-synuclein fibrils in oligodendrocytes that form glial cytoplasmic inclusions, a neuropathological hallmark and central player in the pathogenesis of MSA. Here, we summarize the current knowledge on the etiopathogenesis and neuropathology of MSA. We discuss the role of α-synuclein pathology, microglial activation, oligodendroglial dysfunction and putative cell death mechanisms as candidate therapeutic targets in MSA.

Interventional trials in atypical parkinsonism.

Atypical parkinson disorders (APD) are rapidly progressive neurodegenerative diseases with a variable clinical presentation that may even mimic Parkinson's disease. Multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD) are commonly summarized under this umbrella term. Significant developments in research have expanded knowledge and have broadened available symptomatic treatments, particularly for the treatment of neurogenic orthostatic hypotension. Nonetheless, symptomatic support still remains limited in all of these disorders. Currently, there exists no effective treatment to delay disease progression and disease-modifying trials have failed to provide coherent and convincing results. Recent trials of rasagiline (in MSA), rifampicin (in MSA), tideglusib (in PSP) and davunetide (in PSP) reported negative results. Nevertheless, large cohorts of patients were recruited for interventional studies in the last few years which improved our understanding of trial methodology in APDs immensely. In addition, remarkable progress in basic research has been reported recently and will provide a solid foundation for future therapeutic trials. In this review, we will summarize published randomized, placebo-controlled clinical trials (RCTs) in APDs. Additionally, the design of ongoing and unpublished interventions will be presented.

New insights into orthostatic hypotension in multiple system atrophy: a European multicentre cohort study.

OBJECTIVES: Orthostatic hypotension (OH) is a key feature of multiple system atrophy (MSA), a fatal progressive neurodegenerative disorder associated with autonomic failure, parkinsonism and ataxia. This study aims (1) to determine the clinical spectrum of OH in a large European cohort of patients with MSA and (2) to investigate whether a prolonged postural challenge increases the sensitivity to detect OH in MSA. METHODS: Assessment of OH during a 10 min orthostatic test in 349 patients with MSA from seven centres of the European MSA-Study Group (age: 63.6 ± 8.8 years; disease duration: 4.2 ± 2.6 years). Assessment of a possible relationship between OH and MSA subtype (P with predominant parkinsonism or C with predominant cerebellar ataxia), Unified MSA Rating Scale (UMSARS) scores and drug intake. RESULTS: 187 patients (54%) had moderate (> 20 mm Hg (systolic blood pressure (SBP)) and/or > 10 mm Hg (diastolic blood pressure (DBP)) or severe OH (> 30 mm Hg (SBP) and/or > 15 mm Hg (DBP)) within 3 min and 250 patients (72%) within 10 min. OH magnitude was significantly associated with disease severity (UMSARS I, II and IV), orthostatic symptoms (UMSARS I) and supine hypertension. OH severity was not associated with MSA subtype. Drug intake did not differ according to OH magnitude except for antihypertensive drugs being less frequently, and antihypotensive drugs more frequently, prescribed in severe OH. CONCLUSIONS: This is the largest study of OH in patients with MSA. Our data suggest that the sensitivity to pick up OH increases substantially by a prolonged 10 min orthostatic challenge. These results will help to improve OH management and the design of future clinical trials.

[Predictors of mental and physical quality of life in Huntington's disease]. / Prädiktoren der psychischen und physischen Lebensqualität beim Morbus Huntington.

BACKGROUND: The assessment of health-related quality of life (hrQoL) is an important tool in therapy studies and in the treatment of patients with Huntington's disease (HD). In the absence of causal interventions, HD therapy targets the alleviation of symptoms aiming to improve impaired hrQoL. The aim of this study was to determine the impact of disease characteristics on hrQoL in HD. METHODS: A total of 80 genetically confirmed HD patients underwent an assessment using the Unified Huntington's Disease Rating Scale, the Beck Depression Inventory, the Hamilton Rating Scale and the SF-36, a scale for the assessment of physical and mental QoL. RESULTS: Multiple regression analysis revealed that health-related physical and mental QoL was considerably influenced by the functional capacity. The mental QoL also correlated with the degree of depressive symptoms, age and the number of CAG repeats. However, there was no statistical relation between QoL and motor and cognitive abilities. DISCUSSION: This study underlines the relationship between function capacity and depressive symptoms with mental and physical QoL. This is the first time that hrQoL has been investigated in a German speaking cohort. The results are in accordance with previous studies of hrQoL in HD.

[MSA-QoL: disease-specific questionnaire to assess health-related quality of life in multiple system atrophy: validation of the German translation]. / MSA-QoL: spezifisches Bewertungsinstrument zur Erfassung der Lebensqualität bei Multisystematrophie : Validierung der deutschsprachigen Übersetzung.

BACKGROUND: Multiple system atrophy (MSA) is a rapidly progressive neurodegenerative disorder which causes early sustained disability and quality of life impairment. Recently, a self-reported questionnaire focusing on MSA-specific symptoms (Multiple System Atrophy Quality of Life questionnaire, MSA-QoL) was developed in the English language. This article reports the validation of the German translation of the MSA-QoL. METHODS: Translation of the MSA-QoL was implemented in a 3-tiered approach including a forward translation, a back translation and an independent review. For the validation study 38 consecutive patients with MSA according to the consensus criteria were recruited by the participating centers in a German-Austrian cohort. Data were analyzed using standard psychometric procedures. RESULTS: As determined by the independent review, the German translation of the MSA-QoL was classified as fully equivalent to the English version. The validation study confirmed good psychometric properties of the rating scale. CONCLUSION: The German translation of the MSA-QoL was shown to be a reliable patient-reported rating scale to determine health-related quality of life in MSA patients.

A cross-sectional multicenter study of cognitive and behavioural features in multiple system atrophy patients of the parkinsonian and cerebellar type.

Imaging and neuropathology studies have demonstrated significant abnormalities not only in subcortical, but also in cortical regions of patients with multiple system atrophy (MSA). This raises the possibility that cognitive dysfunction may contribute to the clinical spectrum of this disorder to a greater extent than it is currently not widely appreciated. In this cross-sectional multicenter study from the European multiple system atrophy study group ( http://www.emsa-sg.org ), we applied an extensive neuropsychological test battery in a series of 61 clinically diagnosed probable MSA patients. The results demonstrated that general cognitive decline as assessed by MMSE was uncommon (2 out of 61 patients <24). In contrast, frontal lobe-related functions (as measured by FAB) were impaired in 41 % of patients, with abstract reasoning and sustained attention less compromised. This pattern was similar to our control group of 20 patients with Parkinson's disease (matched for disease duration and age at onset). There was no difference in cognitive performance between MSA patients with the parkinsonian versus the cerebellar variant. Behaviourally, MSA patients had greater depression than PD and in the case of MSA of the cerebellar variant significantly lower anxiety. Our data show that cognitive abnormalities are relatively frequent in multiple system atrophy and this involves primarily frontal-executive functions. Their contribution to clinical disability and disease progression needs to be addressed in larger prospective studies.

EFNS/MDS-ES/ENS [corrected] recommendations for the diagnosis of Parkinson's disease.

BACKGROUND: A Task Force was convened by the EFNS/MDS-ES Scientist Panel on Parkinson's disease (PD) and other movement disorders to systemically review relevant publications on the diagnosis of PD. METHODS: Following the EFNS instruction for the preparation of neurological diagnostic guidelines, recommendation levels have been generated for diagnostic criteria and investigations. RESULTS: For the clinical diagnosis, we recommend the use of the Queen Square Brain Bank criteria (Level B). Genetic testing for specific mutations is recommended on an individual basis (Level B), taking into account specific features (i.e. family history and age of onset). We recommend olfactory testing to differentiate PD from other parkinsonian disorders including recessive forms (Level A). Screening for pre-motor PD with olfactory testing requires additional tests due to limited specificity. Drug challenge tests are not recommended for the diagnosis in de novo parkinsonian patients. There is an insufficient evidence to support their role in the differential diagnosis between PD and other parkinsonian syndromes. We recommend an assessment of cognition and a screening for REM sleep behaviour disorder, psychotic manifestations and severe depression in the initial evaluation of suspected PD cases (Level A). Transcranial sonography is recommended for the differentiation of PD from atypical and secondary parkinsonian disorders (Level A), for the early diagnosis of PD and in the detection of subjects at risk for PD (Level A), although the technique is so far not universally used and requires some expertise. Because specificity of TCS for the development of PD is limited, TCS should be used in conjunction with other screening tests. Conventional magnetic resonance imaging and diffusion-weighted imaging at 1.5 T are recommended as neuroimaging tools that can support a diagnosis of multiple system atrophy (MSA) or progressive supranuclear palsy versus PD on the basis of regional atrophy and signal change as well as diffusivity patterns (Level A). DaTscan SPECT is registered in Europe and the United States for the differential diagnosis between degenerative parkinsonisms and essential tremor (Level A). More specifically, DaTscan is indicated in the presence of significant diagnostic uncertainty such as parkinsonism associated with neuroleptic exposure and atypical tremor manifestations such as isolated unilateral postural tremor. Studies of [(123) I]MIBG/SPECT cardiac uptake may be used to identify patients with PD versus controls and MSA patients (Level A). All other SPECT imaging studies do not fulfil registration standards and cannot be recommended for routine clinical use. At the moment, no conclusion can be drawn as to diagnostic efficacy of autonomic function tests, neurophysiological tests and positron emission tomography imaging in PD. CONCLUSIONS: The diagnosis of PD is still largely based on the correct identification of its clinical features. Selected investigations (genetic, olfactory, and neuroimaging studies) have an ancillary role in confirming the diagnosis, and some of them could be possibly used in the near future to identify subjects in a pre-symptomatic phase of the disease.

[Atypical Parkinson syndromes--recent advances in diagnosis and therapy]. / Atypische Parkinson-Syndrome - Aktuelles aus Diagnostik und Therapie.

The term "atypical Parkinson syndromes" usually encompasses the following diseases: multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS). The differential diagnosis is still a challenge even for a movement disorders specialist, not least because of the distinct therapeutic approaches and disease prognosis. The aim of this review is to provide an overview of current diagnostic criteria and therapeutic approaches and to cite recent findings from clinical and experimental studies.

TDP-43 pathology occurs infrequently in multiple system atrophy.

AIMS AND METHODS: The α-synucleinopathy multiple system atrophy (MSA) and diseases defined by pathological 43-kDa transactive response DNA-binding protein (TDP-43) or fused in sarcoma (FUS) aggregates such as amyotrophic lateral sclerosis and frontotemporal lobar degeneration show overlapping clinico-pathological features. Consequently, we examined MSA for evidence of TDP-43 or FUS pathology utilizing immunohistochemical studies in autopsy material from 29 MSA patients. RESULTS: TDP-43 pathology was generally rare, and there were no FUS lesions. The TDP-43 lesions were located predominantly in medio-temporal lobe and subcortical brain areas and were comprised mainly of dystrophic processes and perivascular (and subpial) lesions. CONCLUSIONS: The multisystem clinical symptoms and signs of MSA, and in particular the neurobehavioural/cognitive and pyramidal features, appear not to result from concomitant TDP-43 or FUS pathology, but rather from widespread white matter α-synuclein positive glial cytoplasmic inclusions and neurodegeneration in keeping with a primary α-synuclein-mediated oligodendrogliopathy. The gliodegenerative disease MSA evidently results from different pathogenetic mechanisms than neurodegenerative diseases linked to pathological TDP-43.

Diagnostic criteria for multiple system atrophy and progressive supranuclear palsy.

The atypical parkinsonian disorders (APD) embrace a heterogeneous group of movement disorders all characterized by prominent parkinsonism, accompanied by specific additional features such as cerebellar ataxia, early autonomic dysfunction, early dementia, pyramidal tract signs, myoclonus, supranuclear gaze palsy, apraxia which are atypical for idiopathic Parkinson's disease (PD). Beside these features, rapid disease progression and poor or absent response to L-Dopa therapy both raise the suspicion of an APD. Currently, multiple system atrophy (MSA), progressive supranuclear palsy (PSP), corticobasal degeneration (CBD) and dementia with Lewy bodies (DLB) are referred to as APD. Clinical diagnosis can be difficult in early stages and although the predictive value of the widely established, diagnostic criteria is high at first neurological evaluation sensitivity tends to be poor and may be less than 30%. In this review, we will discuss diagnostic issues in MSA and PSP.

Decision making under risk and under ambiguity in Parkinson's disease.

In the present study we investigate decision making under ambiguity and decision making under risk in Parkinson's disease (PD) patients without cognitive impairment and in patients affected by Parkinson's disease dementia (PDD). In decisions under ambiguity, participants are not aware of the rules for gains and losses and have to learn about the utility of their selections through feedback. The two patient groups showed significant deficits and did not differ in the frequency of advantageous choices, though they had a markedly different cognitive profile. In decisions under risk, explicit information on the options' probabilities as well as on the associated gains and losses is given. PD patients and healthy controls performed at the same level, whereas PDD patients made significantly more risky and disadvantageous decisions. Results of the study suggest that both patient groups are impaired in decision making when learning by feedback and emotional processing is required, while only the PDD group shows difficulties when decision making is based on cognitive reasoning strategies.

Second consensus statement on the diagnosis of multiple system atrophy.

BACKGROUND: A consensus conference on multiple system atrophy (MSA) in 1998 established criteria for diagnosis that have been accepted widely. Since then, clinical, laboratory, neuropathologic, and imaging studies have advanced the field, requiring a fresh evaluation of diagnostic criteria. We held a second consensus conference in 2007 and present the results here. METHODS: Experts in the clinical, neuropathologic, and imaging aspects of MSA were invited to participate in a 2-day consensus conference. Participants were divided into five groups, consisting of specialists in the parkinsonian, cerebellar, autonomic, neuropathologic, and imaging aspects of the disorder. Each group independently wrote diagnostic criteria for its area of expertise in advance of the meeting. These criteria were discussed and reconciled during the meeting using consensus methodology. RESULTS: The new criteria retain the diagnostic categories of MSA with predominant parkinsonism and MSA with predominant cerebellar ataxia to designate the predominant motor features and also retain the designations of definite, probable, and possible MSA. Definite MSA requires neuropathologic demonstration of CNS alpha-synuclein-positive glial cytoplasmic inclusions with neurodegenerative changes in striatonigral or olivopontocerebellar structures. Probable MSA requires a sporadic, progressive adult-onset disorder including rigorously defined autonomic failure and poorly levodopa-responsive parkinsonism or cerebellar ataxia. Possible MSA requires a sporadic, progressive adult-onset disease including parkinsonism or cerebellar ataxia and at least one feature suggesting autonomic dysfunction plus one other feature that may be a clinical or a neuroimaging abnormality. CONCLUSIONS: These new criteria have simplified the previous criteria, have incorporated current knowledge, and are expected to enhance future assessments of the disease.

Are trials of intravascular infusions of autologous mesenchymal stem cells in patients with multiple system atrophy currently justified, and are they effective?

Scientists and patients are keen to apply new experimental techniques to human diseases, especially currently untreatable progressive neurodegenerative diseases, of which multiple system atrophy (MSA) is an example. We argue that it behooves us to first have robust preclinical experimental evidence before launching into such studies in humans, and to control as much as possible for confounding effects when such trials come to be performed.

Impact of ambiguity and risk on decision making in mild Alzheimer's disease.

Decisions under ambiguity and decisions under risk are crucial types of decision making in daily living at any age. This is the first study assessing these two types of decisions in patients with mild dementia of Alzheimer's type (DAT) by means of the Iowa Gambling Task (IGT) and a newly developed, Probability-Associated Gambling (PAG) task. While rules for gains and losses are implicit in the IGT, in the PAG task rules are explicit and winning probabilities, which change from trial to trial, can be estimated. Results of the IGT indicated that DAT patients made more disadvantageous decisions than healthy controls. Patients also shifted more frequently among decks, i.e. under ambiguity decisions were taken randomly and no advantageous strategy was established over time by DAT patients. Thus, not only actual choices but also development of advantageous strategies may be revealing about decision making in the IGT. Compared to controls, patients demonstrated less advantageous choices in the PAG task as well. They gambled more often in the low winning probabilities and less frequently in the high probabilities than healthy participants. Patients' performance on both tasks correlated with measures of executive functions. Findings of the present investigation are consistent with the early pathological cerebral changes and related (cognitive, emotional) deficits reported for DAT. As suggested by our study, decisions under ambiguity as well as decisions under risk are impaired in mild DAT. It may thus be expected that patients with mild DAT have difficulties in taking decisions in every-day life situations, both in cases of ambiguity (information on probability is missing or conflicting, and the expected utility of the different options is incalculable) and in cases of risk (outcomes can be predicted by well-defined or estimable probabilities).