Background and purpose Amyotrophic lateral sclerosis (ALS) is characterized by rapidly progressive paralysis of striated muscles due to the loss of upper and lower motor neurons. The disease leads to death within 25years, mainly due to respiratory failure. The pathogenesis of ALS is still unexplained for the most part. In this study, we aimed to determine the prevalence of different cardiovascular, metabolic, and neuropsychiatric comorbidities in a large ALS cohort and to evaluate their influence on the disease course. Methods A cohort of 514 patients with ALS of our ALS outpatient clinic was investigated retrospectively with reference to known prognostic factors and comorbidities. The prevalence of concomitant diseases was compared with the data from the German general population. Uni- and multivariate survival analyses were performed using the Cox proportional hazards model and KaplanMeier analysis. Results The prevalence of cardiovascular diseases and cardiovascular risk factors was significantly lower in patients with ALS compared to the German general population, whilst the prevalence of dementia, parkinsonism, and depressive symptoms was significantly higher in the ALS cohort. None of the investigated comorbidities had an influence on the disease course or on the survival of patients. Conclusions Persons with cardiovascular diseases or risk factors seem to be at lower risk of ALS. Although these diseases are apparently somehow protective regarding ALS susceptibility, their presence did not modify disease progression and survival in patients with ALS. Our study further confirms the well-known continuum between ALS and dementia. It also suggests a link with other neurodegenerative diseases such as Parkinson's disease.

Amyotrophic lateral sclerosis is a devastating motoneuron disorder for which no effective treatment exists. There is some evidence for neuroprotective effects of valproic acid (VPA). The beneficial effects, however, are limited due to the adverse effects of VPA. To overcome this problem, a number of VPA derivates with fewer side effects have been synthesized. In the present study, we investigated the viability of highly purified embryonic motoneurons cultured on glial feeder layers, composed of either astrocytes or Schwann cells, or in monoculture, in presence of VPA and its three derivates 3-propyl-heptanoic acid (3-PHA), PE-4-yn enantiomers (R- and S-PE-4-yn). An excitotoxic stimulus, kainate (KA), was added at day in vitro 9 (DIV9) and the neuroprotective effect of either simultaneous incubation (DIV9) or pre-incubation (DIV1) of VPA and its derivates was tested. The survival of motoneurons under simultaneous application of KA and VPA derivates was not remarkably increased. Pre-incubation with VPA and even more with the derivates before the addition of KA, however, significantly reduced their vulnerability against the KA-induced neurotoxic effect. Our data suggest that the neuroprotective capacities of VPA and its three derivates tested here drastically increase when they are added several days before KA. Most prominent neuroprotective effects were seen for the PE-4-yn enantiomers. Patch-clamp experiments revealed an antiexcitotoxic effect of the S-PE-4-yn enantiomer that reduces the frequency of postsynaptic currents and enhances the inhibitory postsynaptic transmission dependent on the co-culture condition.

Objective: Cervical dystonia ( CD) is the most common form of adult-onset focal dystonia, and botulinum toxin A (BoNT-A) has become the first-line treatment for this condition.Methods: In this work, we present data of 207 CD patients treated with BoNT-A for 6.7 +/- 3.5 years. One hundred and sixty-three patients were treated with Dysport ( mean dose, 389 +/- 144 U) and 44 with Botox (mean dose, 145 +/- 44 U).Results: The mean clinical benefit, based on a 0-3 scale (0=no effect, 1=slight, 2=moderate and 3=marked improvement) was similar for Dysport (2.5 +/- 0.3) and Botox (2.2 +/- 0.4). Adverse events were mild and similar for both products. Fewer than 2% of the patients developed neutralizing antibodies.Discussion: These data confirm the efficacy and safety of BoNT-A treatment in CD over an extended period of up to 14 years. [Neurol Res 2009; 31: 463-466]

Chronic dysregulation of the intracellular Ca(2+) homeostasis (excitotoxicity) is thought to contribute to the development of motor neuron diseases. Valproic acid (VPA) is widely used as an antiepileptic drug and acts mainly by inhibition of sodium channels and by enhancing the level of the inhibitory neurotransmitter gamma-aminobutyric acid. Neuroprotective capacities of VPA are supposed to arise also from the inhibition of histone deacetylases. We investigated the viability of highly purified rat embryonic motor neurons cultured on glial feeder layers, composed of either astrocytes or Schwann cells, or in the absence of glia, monoculture in presence of VPA and/or kainate (KA) using immunocytochemistry and calcium imaging. A significant effect of the culture and co-culture conditions on the viability of motor neurons in our in vitro model of excitotoxicity was detected. The neuroprotective effect of VPA on primary embryonic motor neuron cultures was not proven. A functional interaction between VPA and KA occurred during the first 10 days in culture.

Objective: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder of upper and lower motor neurons with a progressive limbic or bulbar muscular weakness and wasting. Survival of patients with bulbar onset is known to be shorter than of patients with lumbar onset. In this study we investigated the cortical activity during movements of tongue, eyes and extremities with fMRI.

Gamma-aminobutyric acid receptor type A (GABA(A)) receptor channels mediate fast inhibitory neurotransmission throughout the central nervous system while the expression of ionotropic glycine receptors is mainly restricted to the spinal cord and brain stem. Neuroactive steroids are well known as positive allosteric modulators of GABA(A) receptor function. Furthermore, there have been hints for an interaction of neuroactive steroids with ionotropic glycine receptors. The aim of the study was to characterize the effect of androsterone and progesterone on alpha(1) and alpha(1)beta glycine receptor and alpha(1)beta(2)gamma(2) GABA(A) receptor channels and to examine the molecular interactions between ligands and receptors. Electrophysiological recordings were performed on HEK 293 cells using the patch clamp technique in combination with an ultrafast perfusion system. A direct activation of inhibitory ionotropic receptors was observed for androsterone at GABA(A) receptor channels. A coactivation of currents elicited by nonsaturating agonist concentrations was observed with androsterone and progesterone at glycine and GABA(A) receptor channels. We could show that association of beta subunits with alpha subunits affects the sensitivity of glycine receptors to androsterone. In contrast to previous reports in which recombinant glycine receptors were inhibited by progesterone, a potentiating effect was revealed by our experiments. At concentrations of 0.1 mM and higher, there were also hints to a channel block-like mechanism. In conclusion, different molecular mechanisms of interaction between neuroactive steroids and GABA as well as glycine receptors could be identified and quantitatively described. Our data clarify the role of steroid compounds in the modulation of inhibitory receptor channel function.

Objective: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder of upper and lower motor neurons with a progressive limbic or bulbar muscular weakness and wasting. Survival of patients with bulbar onset is known to be shorter than of patients with lumbar onset. In this study we investigated the cortical activity during movements of tongue, eyes and extremities with fMRI.

Transcriptional dysregulation has been shown both in human sporadic ALS and in the G93A mouse model (Olsen et al., 2001; Malaspina and de Belleroche, 2004; Ishigaki et al., 2002; Yoshihara et al., 2002). Histone deacetylases (HDAC) catalyze the deacetylation of lysine residues in the amino terminals of the highly conserved core histones H2A, H2B, H3, and H4. The posttranscriptional acetylation of lysine residues in the amino terminals of the core histones leads to a neutralization of the positive charge, and opening of the DNA conformation which allows access of transcription factors to target genes. Therefore, acetylation of histones correlates with transcriptional activity and determines specific temporal and spatial gene expression patterns (Pogo et al., 1966; Grunstein, 1997). HDAC enzymes have become potential therapeutic targets for several diseases, among them malignant, cardiovascular and neurodegenerative disorders. In the G93A-ALS-mouse model, HDAC inhibitors have already been shown to have neuroprotective capacities (Ryu et al., 2005; Petri et al., 2006). HDAC can be grouped into four classes, class I (HDAC 1–3, 8), class II (HDAC 4–7, 9, 10), class II (syn. SIRT 1–7) and class IV (HDAC 11) with distinct localization, substrates and physiological roles. The mRNA expression levels of HDAC 1–11 have previously been characterized in rat brain ((Broide et al., 2006) but not yet studied in human tissue.

Amyotrophic lateral sclerosis (ALS) is the most common adult-onset motor neuron disorder with an average survival of 3–5 years after the onset of symptoms. It is characterized by a rapidly progressive paralysis due to the degeneration of motor neurons in primary motor cortex, brain stem and spinal cord. About 90% of cases occur sporadically and 10% are familial. Among the familial cases, 10–20% can be attributed to point mutations in the gene coding for the antioxidant enzyme Cu/Zn superoxide dismutase (SOD1) (Rosen et al., 1993). This discovery led to the generation of mouse models overexpressing common human SOD1 mutations (Gurney et al., 1994). The precise molecular mechanisms leading to motor neuron death have not been fully elucidated, there is, however, ample evidence that oxidative damage by reactive oxygen species (ROS) plays an important role. Mitochondria are the major source of cellular ROS production, which further increases if mitochondria are damaged (Beal, 2005, Hervias et al., 2006). The transcriptional co-activator peroxisome proliferator-activated receptor-gamma co-activator 1alpha (PGC-1alpha) plays a pivotal role in the regulation of mitochondrial metabolism and biogenesis via activation of transcription factors such as nuclear respiratory factor-1 (NRF-1) (Scarpulla, 2006). Alterations in PGC-1alpha expression and function have previously been described in models of Huntington's and Alzheimer's disease (Weydt et al., 2006, Shi and Gibson, 2007).

The antiepileptic drug riluzole is used as a therapeutic agent in amyotrophic lateral sclerosis due to its neuroprotective effects. Besides presynaptic inhibition of GABAergic and preferentially glutamatergic transmission, it also potentiates postsynaptic GABAA-receptor function. We investigated the postsynaptic effects of riluzole on GABAA-receptor channels by use of the patch-clamp technique. Recombinant α1β2γ2s and α1β2 GABAA receptors were expressed in HEK 293 cells by transient transfection. Pulses of GABA were applied in combination with different concentrations of riluzole to whole cell or outside-out patches with either α1β2γ2s or α1β2 GABAA-receptor channels. Co-application of riluzole led to a slight decrease of absolute peak current amplitudes and steady-state currents in prolonged presence of GABA at saturating concentrations. In the presence of riluzole, enhancement of current amplitudes was observed with lower concentrations of GABA at α1β2γ2s receptors and to a lower extent also at α1β2 receptors. Thus, the potentiating effect of riluzole was shown to be not abolished in the absence of the γ2s-subunit. A further prominent effect of riluzole was a highly significant acceleration of the time course of current decay, most probably pointing to an open-channel block-like mechanism of action. As both receptor subtypes were affected similarly by the block, it could be concluded that the respective binding sites should be assumed within a region of high sequence homology like it is given for the channel-lining M2 domain of GABAA-receptor subunits. In conclusion, three different molecular mechanisms of interaction of the neuroprotective compound riluzole were observed at two different subtypes of GABAA receptor channels. The results further point to the impact of the inhibitory as well as the excitatory synaptic activity as a pharmacological target to counteract chronic excitotoxicity and reveal molecular mechanisms of action of the only one neuroprotective drug in current clinical use in patients suffering from amyotrophic lateral sclerosis.

We describe three patients referred to our ALS/MND clinic with suspected diagnosis of amyotrophic lateral sclerosis (ALS). The patients were all male, middle aged, and their initial symptoms were weakness and fasciculations in upper limb muscles. Results of clinical and electrophysiological examination in all cases were in accordance with possible ALS according to the revised El Escorial criteria. Other conditions mimicking ALS appeared to be excluded by extensive technical examinations and laboratory tests. Only repeated MRI examinations revealed anterior spinal cysts several years after symptom onset. This report intends to highlight this rare and difficult differential diagnosis of ALS and underlines the value of the revised El Escorial criteria in conjunction with electrophysiology to asses the certainty of the diagnosis ALS.

Amyotrophic lateral sclerosis (ALS) is the most common adult-onset motor neuron disorder with an average survival of 3–5 years after the onset of symptoms. It is characterized by a rapidly progressive loss of upper motor neurons in the primary motor cortex and lower motor neurons in brainstem and spinal cord. A defined genetic defect (mutations in the Superoxide Dismutase (SOD) 1 gene) is detected in about 20 percent of familial cases. Most ALS-cases, however, occur sporadically. Many different pathomechanisms such as excitotoxicity, oxidative stress, disruption of axonal transport, lack of neurotrophic factors and oxidative stress are discussed in sporadic ALS.

Neurodegeneration in several diseases like amyotrophic lateral sclerosis is at least in part caused by chronic excitotoxicity. AMPA-receptor-mediated fast excitatory synaptic transmission induces an increase of the intracellular calcium-concentration, that might explain one pathway in the pathophysiological model of chronical excitotoxicity. Therefore, neuroprotection by antagonising AMPA-receptor mediated synaptic transmission by selective AMPA-type-receptor blockers is a promising strategy albeit AMPA-type-receptor blockers show a lot of (neuro)toxic side effects. An urgent aim of drug design is to develop more selective AMPA-type- receptor blockers (e.g. subunit selectivity) that results in less side effects and better tolerability. Patch clamp experiments are a useful method to elucidate specific pharmacological effects on kinetics of AMPA-type receptor channels. experiments were performed on recombinant homomeric and heteromeric AMPA receptor channels expressed in HEK293-cells. Drug application was performed using a fast application system based on a piezo driven liquid filament switch. Our study shows four different AMPA-receptor antagonists (ZK200775, ZK187638, ZK238519, ZK166350), differentiated in their specific electrophysiological pharmacological properties and blocking mechanisms via different drug application and patch clamp techniques. We observed a dose-dependent competitive block effect for ZK200775 and ZK238519 and a non-competitive block effect for ZK187638 and ZK166350. The quantitative details of the interaction of the tested compounds with AMPA type receptor channels were integrated in reaction models that allow for computer simulation. The results are a quantitative basis for further drug design testing analogues of the compounds in vivo (motoneuron cultures and SOD1 animal model of ALS) and in vitro.

Amyotrophic lateral sclerosis (ALS) is a late-onset progressive neurodegenerative disease characterized by substantial loss of motor neurons in the spinal cord, brain stem and motor cortex. Synaptic over-excitation (excitotoxicity) of vulnerable motoneurons is thought to be of major impact for the pathophysiology of this selective neurodegeneration. Valproic acid (2-propylpentanoic acid, VPA) is one of the most frequently prescribed antiepileptic drugs and acts mainly by a blockade of voltage dependent Na- and K-channels and by an enhancement of GABAergic inhibition as a gamma-aminobutyric acid (GABA) transaminase inhibitor.

The strychnine-sensitive glycine receptor (GlyR) is a member of an ion channel superfamily which includes nicotinic acetylcholine, GABAA and serotonin (5-HT3) receptor channels. The highest density of expression is found in the brain stem and spinal cord. There is a high degree of sequence homology between the members of the superfamily, especially regarding the M2 domain i.e. the channel lining domain of the transmembraneous functional receptor channel protein. There are reports on a block of ligand gated ion channels by higher concentrations of the respective neurotransmitters. This could be a molecular mechanism of modulation of the current response to peak doses of synaptic transmitter release. The electrophysiological properties of GlyR are well known for the activation by concentrations of the agonist glycine <1mM. To analyze the effect of the agonist glycine in a higher concentration range in homomeric alpha1-GlyR and heteromeric alpha1/beta1- GlyR we applied 1 mM, 3 mM, 10 mM and 30 mM glycine to small-cells in the whole-cell configuration or patches in the outside-out configuration using the patch-clamp technique. Patch clamp experiments were performed on glycine receptor channels expressed in HEK293-cells. Different electrophysiological parameters, e.g. activation, deactivation and desensitisation were analysed using ultrafast piezo-driven application of test solution. By this approach, we observed a mild decrease of amplitude, an increased rate of current decay in presence of the agonist and a re-opening current after removing the agonist in a dose-dependent manner due to an open-channel-block like mechanism. Similar results were reported for the nicotinic acetylcholine receptor and the GABAA-receptor, but were not documented for the glycine receptor channel so far. Further experiments should elucidate a potential physiological role of this receptor channel property and potential pharmacological modulation.

Objective: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder of upper and lower motor neurons. The neurodegenerative process is already advanced before muscle weakness and wasting occurs. In this study we investigated the motor activations using fMRI with a focus on unaffected limbs.

Introduction: Only few data regarding the long-term follow-up of patients treated with albumin-diluted botulinum toxin (BTX) type A (Dysport®) have been published to date. In this study we present the data of 177 patients who received albumin-diluted BTX type A over a period of up to ten years with the diagnosis of dystonia, spasticity, writers cramp, blepharospasm, facial hemispasm and hyperhidrosis.