[Show abstract][Hide abstract] ABSTRACT: A massive expansion of a GGGGCC repeat upstream of the C9orf72 coding region is the most common known cause of amyotrophic lateral sclerosis and frontotemporal dementia. Despite its intronic localization and lack of a canonical start codon, both strands are translated into aggregating dipeptide repeat (DPR) proteins: poly-GA, poly-GP, poly-GR, poly-PR and poly-PA. To address conflicting findings on the predominant toxicity of the different DPR species in model systems, we compared the expression pattern of the DPR proteins in rat primary neurons and postmortem brain and spinal cord of C9orf72 mutation patients. Only poly-GA overexpression closely mimicked the p62-positive neuronal cytoplasmic inclusions commonly observed for all DPR proteins in patients. In contrast, overexpressed poly-GR and poly-PR formed nucleolar p62-negative inclusions. In patients, most of the less common neuronal intranuclear DPR inclusions were para-nucleolar and p62 positive. Neuronal nucleoli in C9orf72 cases showed normal size and morphology regardless of the presence of poly-GR and poly-PR inclusions arguing against widespread nucleolar stress, reported in cellular models. Colocalization of para-nucleolar DPR inclusions with heterochromatin and a marker of transcriptional repression (H3K9me2) indicates a link to gene transcription. In contrast, we detected numerous intranuclear DPR inclusions not associated with nucleolar structures in ependymal and subependymal cells. In patients, neuronal inclusions of poly-GR, poly-GP and the poly-GA interacting protein Unc119 were less abundant than poly-GA inclusions, but showed similar regional and subcellular distribution. Regardless of neurodegeneration, all inclusions were most abundant in neocortex, hippocampus and thalamus, with few inclusions in brain stem and spinal cord. In the granular cell layer of the cerebellum, poly-GA and Unc119 inclusions were significantly more abundant in cases with FTLD than in cases with MND and FTLD/MND. Poly-PR inclusions were rare throughout the brain but significantly more abundant in the CA3/4 region of FTLD cases than in MND cases. Thus, although DPR distribution is not correlated with neurodegeneration spatially, it correlates with neuropathological subtypes.
[Show abstract][Hide abstract] ABSTRACT: Major depressive disorder is a severe and chronic illness with high lifetime prevalence and a high incidence of suicide as the cause of death for patients with this diagnosis. Major depressive disorder is often treated with antidepressants. Although these drugs have been used for many years, their exact mode of action is still unknown. It has been suggested that many antidepressants act by increasing the concentrations of serotonergic transmitters in the synaptic space. However, recent studies have examined the effects of antidepressants on neurogenesis in the hippocampus, the restoration of hippocampal neuronal networks that may be affected by major depression, and the regulation of the hypothalamic-pituitary-adrenal axis by immature neurons in the hippocampus. Here we present and discuss a novel hypothesis suggesting that these events are regulated by the concentrations of sphingolipids, in particular ceramide, in the hippocampus. These concepts suggest that the acid sphingomyelinase/ceramide system plays a central role in the pathogenesis of major depression and may be a novel target for antidepressants. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
Journal of Neurochemistry 04/2015; 134(2). DOI:10.1111/jnc.13145 · 4.24 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: There is evidence that nigrostriatal pathology may at least partly underlie mild Parkinsonian signs. We evaluated whether an increase in the Unified Parkinson’s Disease Rating Scale part III (UPDRS-III) could be predicted by the presence of risk and prodromal markers for neurodegenerative diseases in elderly individuals without those diseases. Therefore, we analyzed the UPDRS-III score and various risk and prodromal markers known to antecede neurodegenerative diseases in a population-based cohort comprising 807 individuals free of neurodegenerative diseases at baseline. After 5 years, eight persons (1.0 %) were diagnosed with Parkinson’s Disease (PD). Of those, seven (87.5 %) had motor worsening ≥3 points on the UPDRS-III from baseline to follow-up, one had two points increase. Of the 788 people without PD, 568 (72.1 %) showed no increase in the UPDRS-III scale, 220 (27.9 %) had ≥1 point increase and out of these 104 (13.2 %) had an increase of ≥3 points in the UPDRS-III score after 5 years. We identified an age >60 years (relative risk, RR = 1.7; confidence interval, CI 1.3–2.1) and the occurrence of ≥2 risk factors (RR = 1.5; CI 1.2-1.9) as possible predictors of motor progression. After 5 years, individuals with an increase in the UPDRS-III score had more often a one-sided reduced arm swing (p p UPDRS-III parallels the development of prodromal markers for neurodegenerative diseases in the elderly population.
Journal of Neurology 12/2014; 262(2). DOI:10.1007/s00415-014-7584-4 · 3.84 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This article presents the evidence-based pharmacotherapeutic options for the most common forms of neurodegenerative dementia. The aim is to present the recommendations derived from the relevant studies on the neurological, psychiatric and geriatric practice of treatment for dementia patients. The text is derived from the 2009 guidelines of the German Society of Neurology (DGN, lead management: K. Fassbinder), the S3 guidelines of the DGN/German Association for Psychiatry, Psychotherapy and Psychosomatics (DGPPN, lead management: G. Deuschl and W. Maier) and the latest amendments of the European Federation of Neurological Societies/European Society of Neurology (EFNS-ENS, Sorbi et al. Eur J Neurol 19:1159-1179, 2012) guidelines. The forms of neurodegenerative dementia addressed are Alzheimer's disease, frontotemporal dementia and Lewy body dementia. Specific statements on the treatment of dementia in Parkinson's disease and vascular dementia can be found in separate guidelines. An analogous article on psychosocial interventions was recently published in Der Nervenarzt (Kurz, Nervenarzt 84:93-103, 2013).
Der Nervenarzt 12/2014; 85(12):1589-602. DOI:10.1007/s00115-014-4189-1 · 0.86 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Alzheimer's disease (AD) is characterized by extracellular amyloid-β (Aβ) deposits and microglia-dominated inflammatory activation. Innate immune signaling controls microglial inflammatory activities and Aβ clearance. However, studies examining innate immunity in Aβ pathology and neuronal degeneration have produced conflicting results. In this study, we investigated the pathogenic role of innate immunity in AD by ablating a key signaling molecule, IKKβ, specifically in the myeloid cells of TgCRND8 APP-transgenic mice. Deficiency of IKKβ in myeloid cells, especially microglia, simultaneously reduced inflammatory activation and Aβ load in the brain and these effects were associated with reduction of cognitive deficits and preservation of synaptic structure proteins. IKKβ deficiency enhanced microglial recruitment to Aβ deposits and facilitated Aβ internalization, perhaps by inhibiting TGF-β-SMAD2/3 signaling, but did not affect Aβ production and efflux. Therefore, inhibition of IKKβ signaling in myeloid cells improves cognitive functions in AD mice by reducing inflammatory activation and enhancing Aβ clearance. These results contribute to a better understanding of AD pathogenesis and could offer a new therapeutic option for delaying AD progression.
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience 09/2014; 34(39):12982-99. DOI:10.1523/JNEUROSCI.1348-14.2014 · 6.75 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We investigated in vivo brain nicotinic acetylcholine receptor (nAChR) distribution in cognitively intact subjects with Parkinson's disease (PD) at an early stage of the disease. Fourteen patients and 13 healthy subjects were imaged with single photon emission computed tomography and the radiotracer 5-[(123)I]iodo-3-[2(S)-2-azetidinylmethoxy]pyridine ([(123)I]5IA). Patients were selected according to several criteria, including short duration of motor signs (<7 years) and normal scores at an extensive neuropsychological evaluation. In PD patients, nAChR density was significantly higher in the putamen, the insular cortex and the supplementary motor area and lower in the caudate nucleus, the orbitofrontal cortex, and the middle temporal gyrus. Disease duration positively correlated with nAChR density in the putamen ipsilateral (ρ = 0.56, p < 0.05) but not contralateral (ρ = 0.49, p = 0.07) to the clinically most affected hemibody. We observed, for the first time in vivo, higher nAChR density in brain regions of the motor and limbic basal ganglia circuits of subjects with PD. Our findings support the notion of an up-regulated cholinergic activity at the striatal and possibly cortical level in cognitively intact PD patients at an early stage of disease.
[Show abstract][Hide abstract] ABSTRACT: Introduction
Capecitabine, a 5-fluorouracil (5FU) pro-drug, is increasingly used in breast and gastrointestinal cancers due to its more convenient oral route of administration when compared to 5FU. Despite its widespread use, there are only a few reports on capecitabine CNS toxicity, while the pathogenic basis of such toxicity remains unclear.
A 69-year-old male presented with recurrent generalized seizures 2.5 months after preoperative chemoradiotherapy with capecitabine in locally advanced rectal cancer. Brain MRI revealed a diffuse, subcortical white matter alteration suggestive of vasogenic edema. The diagnosis of toxic encephalopathy was supported after elimination of alternative causes of the neurological dysfunction and complete resolution of clinical and imaging findings after 3 months of no further chemotherapy.
Given the expanding use of capecitabine, physicians should be aware of this potential complication when a neurological worsening occurs during or after treatment with this chemotherapeutic agent. In our case, as in previously described cases encephalopathy was characterized by a favorable course after cessation of the drug. Vasogenic edema rather than cytotoxic edema may play a pivotal pathogenetic role in this form of encephalopathy.
[Show abstract][Hide abstract] ABSTRACT: The enteric nervous system (ENS) has to respond to continuously changing microenvironmental challenges within the gut and is therefore dependent on a neural stem cell niche to keep the ENS functional throughout life. In this study, we hypothesize that this stem cell niche is also affected during inflammation and therefore investigated lipopolysaccharides (LPS) effects on enteric neural stem/progenitor cells (NSPCs). NSPCs were derived from the ENS and cultured under the influence of different LPS concentrations. LPS effects upon proliferation and differentiation of enteric NSPC cultures were assessed using immunochemistry, flow cytometry, western blot, Multiplex ELISA and real-time PCR. LPS enhances the proliferation of enteric NSPCs in a dose-dependent manner. It delays and modifies the differentiation of these cells. The expression of the LPS receptor toll-like receptor 4 on NSPCs could be demonstrated. Moreover, LPS induces the secretion of several cytokines. Flow cytometry data gives evidence for individual subgroups within the NSPC population. ENS-derived NSPCs respond to LPS in maintaining at least partially their stem cell character. In the case of inflammatory disease or trauma where the liberation and exposure to LPS will be increased, the expansion of NSPCs could be a first step towards regeneration of the ENS. The reduced and altered differentiation, as well as the induction of cytokine signalling, demonstrates that the stem cell niche may take part in the LPS-transmitted inflammatory processes in a direct and defined way.
Journal of Cellular and Molecular Medicine 04/2014; 18(7). DOI:10.1111/jcmm.12292 · 3.70 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background
Idiopathic Parkinson's disease (IPD) is characterized by the clinical motor symptoms of hypokinesia, rigidity, and tremor. Apart from these motor symptoms, cognitive deficits often occur in IPD. The positive effect of cholinesterase inhibitors on cognitive deficits in IPD and findings of earlier molecular imaging studies suggest that the cholinergic system plays an important role in the origin of cognitive decline in IPD.Methods
Twenty-five non-demented patients with IPD underwent a 5-[123I]iodo-3-[2(S)-2-azetidinylmethoxy]pyridine (5-I-A-85380) SPECT to visualize α4β2 nicotinic acetylcholine receptors (nAchR) and cognitive testing with the CERAD (Consortium to Establish a Registry for Alzheimer's Disease) battery to identify domains of cognitive dysfunction.ResultsIn the CERAD, the IPD patients exhibited deficits in non-verbal memory, attention, psychomotor velocity, visuoconstructive ability, and executive functions. After Bonferroni correction for multiple comparisons, we found significant correlations between performance of the CERAD subtests Boston Naming Test (a specific test for visual perception and for detection of word-finding difficulties) and Word List Intrusions (a specific test for learning capacity and memory for language information) vs binding of α4β2 nAchR in cortical (the right superior parietal lobule) and subcortical areas (the left thalamus, the left posterior subcortical region, and the right posterior subcortical region).Conclusions
These significant correlations between the results of the CERAD subtests and the cerebral α4β2 nAchR density, as assessed by 5-I-A-85380 SPECT, indicate that cerebral cholinergic pathways are relevant to cognitive processing in IPD.
[Show abstract][Hide abstract] ABSTRACT: Acute stroke is one of the main causes of death and chronic disability. Thrombolysis with recombinant tissue plasminogen activator within the first hours after onset of symptoms is an effective therapeutic option for ischemic stroke. However, fewer than 2% to 7% of patients receive this treatment, primarily because most patients reach the hospital too late for the initiation of successful therapy. Several measures can reduce detrimental delay until treatment. It is of importance to use continual public awareness campaigns to reduce delays in patients' alarm of emergency medical services. Further relevant measures are repetitive education of emergency medical services teams to ensure the systematic use of scales designed for recognition of stroke symptoms and the proper triage of patients to stroke centers. A most important time-saving measure is prenotification of the receiving hospital by the emergency medical services team. In the future, treatment already at the emergency site may allow more than a small minority of patients to benefit from available treatment.
International Journal of Stroke 04/2014; 9(3). DOI:10.1111/ijs.12252 · 4.03 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Aims: The aim was to determine the incidence of new ischaemic lesions on diffusion-weighted MR imaging (DWI) in a non-randomised cohort of patients after protected and unprotected carotid artery stent placement using the Parodi Anti-Emboli System (PAES). Methods and results: A retrospective review was conducted on 269 patients who received DWI prior to, and 24-72 hours after, stent placement. All patients were enrolled in one centre. Forty patients stented with the PAES device were matched with 229 patients stented without protection (control group). New diffusion restriction on DWI was detected in 25.8% (PAES) versus 32.3% (control group); p=0.64. On average there were 0.7 lesions (PAES) versus 0.8 lesions (control group) per patient. The area of lesions was 1.7 (PAES) versus 5.6 mm2. In a subanalysis of patients (32 PAES, 148 non-protected) with >80% stenosis, the area of restricted diffusion was less when proximal protection was used (p<0.05). The number and area of DWI lesions did not differ on the contralateral, non-stented side. When the PAES system was used, patients were more likely not to have any lesion at all (p=0.028). Conclusions: In high-grade stenosis, the use of the Gore PAES device significantly reduced the area of new DWI lesions and patients were more likely not to have any new DWI lesion at all.
EuroIntervention: journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology 02/2014; 10(2). DOI:10.4244/EIJV10I2A45 · 3.76 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Mechanical thrombectomy with stent retrievers in acute stroke has emerged as a promising new technique with the highest recanalization rate of the therapeutic procedures available so far. However, endovascular treatment is also associated with the risk of specific complications. One of those is the occurrence of peri-interventional subarachnoid hemorrhage (SAH), which has been reported in 5-16 % of the cases. Interestingly, this rate is higher than that of angiographically detectable perforations (0-3 %), leaving the majority of peri-interventional SAH to be due to angiographically occult perforations. Little is known about the influence of this finding on clinical outcome. The purpose of this study was to investigate the clinical relevance of SAH due to occult perforations during thrombectomy with stent retrievers.
Postinterventional computed tomography (CT) scans of 217 consecutive patients with acute occlusions of intracerebral arteries who were treated with stent retrievers in our department between October 2009 and October 2012 were retrospectively analyzed.
SAH was found on postinterventional CT scans in 5.5 % of the cases. Seven cases were included for further analysis and matched to controls by the following characteristics: (1) site of occlusion, (2) result of the recanalization procedure according to the modified thrombolysis in cerebral infarction score, (3) administration of intravenous recombinant tissue plasminogen activator, (4) presence of proximal extracranial occlusion, (5) age, and (6) sex. Comparison of the angiographic data of the two cohorts showed no significant difference in the length of the procedures or the number of maneuvers needed for recanalization, nor were there significant differences in clinical outcomes as measured by NIHSS and mRS scores. Secondary symptomatic ICH occurred in one case in either cohort and led to death in both cases. The rate of asymptomatic ICH within the first 24 h after recanalization was significantly higher in the group with peri-interventional SAH (57 vs. 0 %, P = 0.018).
This small retrospective case-control study did not reveal a significant influence of peri-interventional SAH due to angiographically occult perforations on neurologic outcome of patients treated with stent retrievers.
[Show abstract][Hide abstract] ABSTRACT: Wir berichten über 10 Patienten, bei denen nach beruflicher Exposition gegenüber Perchlorethen eine chronischtoxische Enzephalopathie (8 x Grad III, 2 x Grad II b) und andere Erkrankungen diagnostiziert wurden. Nach 15 jährigem follow-up zeigten sich keine wesentlichen Verbesserungen der Defizite. Indes wurden auch progrediente Verschlechterungen trotz Expositionsstopp gesehen. Eine Befundprogredienz Lösemittelbedingter Enzephalopathien ist demnach auch nach Expositionsende durchaus möglich.
We report on 10 patients who developed, as a result of the exposure to perchloroethen, a chronic-toxic encephalopathy (8 times stage III, 2 times stage II b) and other diseases. The follow-up, conducted after 15 years, did not show any significant improvements of the deficits. On the contrary, despite of the fact that the exposure had been terminated, even progressive worsening has been observed. Hence, the progress of chronic-toxic encephalopathy, even after the exposure had been stopped, is most likely.
Zentralblatt für Arbeitsmedizin, Arbeitsschutz und Ergonomie 01/2014; 58(1):4-19. DOI:10.1007/BF03349142
[Show abstract][Hide abstract] ABSTRACT: Acute stroke is one of the main causes of death and chronic disability. Thrombolysis, achieved by administering recombinant tissue plasminogen activator within 4.5 h, is an effective therapeutic option for ischemic stroke. However, less than 2-12 % of patients receive this treatment and a major reason is that most patients reach the hospital too late. Several time-saving measures should be implemented. Firstly, optimized and continual public awareness campaigns for patients should be initiated to reduce delays in notifying the emergency medical service. Secondly, emergency medical service personnel should develop protocols for prenotification of the receiving hospital. Other suggested measures involve educating emergency medical service personnel to systematically use scales for recognizing the symptoms of stroke and to triage patients to experienced stroke centers. In the future, administering treatment at the emergency site (mobile stroke unit concept) may allow more than a small minority of patients to benefit from available recanalization treatment options.
Der Nervenarzt 11/2013; 85(2). DOI:10.1007/s00115-013-3952-z · 0.86 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Alzheimer's disease (AD) is characterized by a progressive decline of cognitive functions and represents the most common form of dementia and a major cause of morbidity and mortality in the modern, Westernized societies. There is accumulating evidence to support the hypothesis that a primary Cerebral vascular dysfunction initiates a cascade of events that lead to neuronal injury in Alzheimer's dementia. The endothelium, in specific, constitutes a part of the blood brain barrier, the dysfunction of which is thought to play an important role to disturbed amyloid-β homeostasis and infiltration of the brain parenchyma with circulating toxic molecules in the disease. Furthermore, the endothelium itself is under certain conditions capable of producing neurotoxic and inflammatory factors, whereas common growth factors regulate the development and maintenance of both neurons and blood vessels. Reliance of both endothelial and neuronal cells on mitochondrial integrity and common molecular pathways for apoptosis also imply that there is a link between vascular pathology and neurodegeneration. The present article intends to review available evidence on molecular players implicated in the above mechanisms with the potential to develop biomarkers or novel therapeutic targets.
Current Alzheimer research 11/2013; 11(1). DOI:10.2174/1567205010666131119235254 · 3.80 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Identification of risk factors and prodromal markers for Parkinson's disease (PD) and the understanding of the point in time of first occurrence is essential for the early detection of incident PD. In this three-center longitudinal, observational study, we evaluated the specific risk for PD associated with single or combinations of risk factors and prodromal markers. In addition, we evaluated which risk factors and prodromal markers emerge at which time before the diagnosis of PD. Of the 1,847 at-baseline PD-free individuals ≥50 years, 1,260 underwent the 5-year follow-up assessment. There were 21 cases of incident PD during the study period. Enlarged hyperechogenic substantia nigra was the most frequent baseline sign in individuals developing PD after 3 years (80.0 %) and 5 years (85.7 %) compared to healthy controls (17.5 %) followed by the occurrence of mild parkinsonian signs and hyposmia. Evaluation of the signs at the first follow-up assessment showed that individuals developing PD after two additional years showed the same pattern of signs as individuals who developed PD 3 years after baseline assessment.
Journal of Neurology 11/2013; 261(1). DOI:10.1007/s00415-013-7171-0 · 3.84 Impact Factor