Metabolic demands of slacklining in less and more advanced slackliners.

Walking or balancing on a slackline has gained increasing popularity as a recreational and school sport, and has been found to be suitable for developing neuromuscular control. The metabolic requirements for neuromuscular control on slackline, however, have not been well described. Therefore, the aim of the study was to determine the metabolic demands of slacklining in less and more advanced slackliners. Nineteen slackliners performed several 4 min balance tasks: parallel and one-leg stance on stable platform (2LS and 1LS), 1 leg stance on a slackline (1LSS), walking at a self-selected speed and at a given speed of 15 m min-1 on a slackline (WSS and WGS). Expired gas samples were collected for all participants and activities using a portable metabolic system. During1 LS and 1LSS, there were 140% and 341% increases in oxygen uptake (V̇O2) with respect to V̇O2 rest, respectively. During slackline walking, V̇O2 increased by 460% and 444% at self-selected and given speed, respectively. More advanced slackliners required mean metabolic demands 0.377 ± 0.065 and 0.289 ± 0.050 kJ·kg-1·min-1 (5.7 ± 0.95 and 3.9 ± 0.6 MET) for WGS and 1LSS, respectively, whilst less advanced slackliners, 0.471 ± 0.081 and 0.367 ± 0.086 kJ·kg-1·min-1 (6.4 ± 1.2 and 5.0 ± 1.1 MET) for WGS and 1LSS, respectively. Our data suggest that balancing tasks on slackline require V̇O2 corresponding to exercise intensities from light to moderate intensity. More advanced slackliners had a ∼25% reduced energy expenditure when compared with lower ability counterparts during simple balance tasks on the slackline.HighlightsBalancing on a slackline is metabolically demanding and slackline training is suitable not only to develop neuromuscular control but also to meet cardiovascular fitness demands.Improved postural control demonstrated by skilled slackliners reduces by ∼25% metabolic cost of balancing tasks on a slackline when compared to less skilled counterparts.Falls during slacklining increase the metabolic demands of the activity. Three falls per minute during walking on a slackline increase the oxygen uptake by ∼50%.

Analysis of the therapeutic potential of different administration routes and frequencies of human mesenchymal stromal cells in the SOD1G93A mouse model of amyotrophic lateral sclerosis.

Cellular therapy represents a novel option for the treatment of neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS). Its major aim is the generation of a protective environment for degenerating motor neurons. Mesenchymal stromal cells secrete different growth factors and have antiapoptotic and immunomodulatory properties. They can easily and safely be isolated from human bone marrow and are therefore considered promising therapeutic candidates. In the present study, we compared intraventricular application of human mesenchymal stromal cells (hMSCs) versus single and repeated intraspinal injections in the mutant SOD1G93A transgenic ALS mouse model. We observed significant reduction of lifespan of animals treated by intraventricular hMSC injection compared with the vehicle treated control group, accompanied by changes in weight, general condition, and behavioural assessments. A potential explanation for these rather surprising deleterious effects lies in increased microgliosis detected in the hMSC treated animals. Repeated intraspinal injection at two time points resulted in a slight but not significant increase in survival and significant improvement of motor performance although no hMSC-induced changes of motor neuron numbers, astrogliosis, and microgliosis were detected. Quantitative real time polymerase chain reaction showed reduced expression of endothelial growth factor in animals having received hMSCs twice compared with the vehicle treated control group. hMSCs were detectable at the injection site at Day 20 after injection into the spinal cord but no longer at Day 70. Intraspinal injection of hMSCs may therefore be a more promising option for the treatment of ALS than intraventricular injection and repeated injections might be necessary to obtain substantial therapeutic benefit.

Intraspinal administration of human spinal cord-derived neural progenitor cells in the G93A-SOD1 mouse model of ALS delays symptom progression, prolongs survival and increases expression of endogenous neurotrophic factors.

Neural stem or progenitor cells are considered to be a novel therapeutic strategy for amyotrophic lateral sclerosis (ALS), based on their potential to generate a protective environment rather than to replace degenerating motor neurons. Following local injection to the spinal cord, neural progenitor cells may generate glial cells and release neurotrophic factors. In the present study, human spinal cord-derived neural progenitor cells (hscNPCs) were injected into the lumbar spinal cord of G93A-SOD1 ALS transgenic mice. We evaluated the potential effect of hscNPC treatment by survival analysis and behavioural/phenotypic assessments. Immunohistological and real-time PCR experiments were performed at a defined time point to study the underlying mechanisms. Symptom progression in hscNPC-injected mice was significantly delayed at the late stage of disease. On average, survival was only prolonged for 5 days. Animals treated with hscNPCs performed significantly better in motor function tests between weeks 18 and 19. Increased production of GDNF and IGF-1 mRNA was detectable in spinal cord tissue of hscNPC-treated mice. In summary, treatment with hscNPCs led to increased endogenous production of several growth factors and increased the preservation of innervated motor neurons but had only a small effect on overall survival. Copyright © 2015 John Wiley & Sons, Ltd.

Altered expression of DJ-1 and PINK1 in sporadic ALS and in the SOD1(G93A) ALS mouse model.

Mitochondrial dysfunction is an important mechanism in the pathogenesis of neurodegenerative diseases such as Parkinson disease and amyotrophic lateral sclerosis (ALS). DJ-1 and PTEN-induced putative kinase 1 (PINK1) are important proteins for the maintenance of mitochondrial function and protection against cell death. Mutations in the genes coding for these proteins cause familial forms of Parkinson disease. Recent studies have postulated that changes in the expression of both proteins are also involved in pathologic mechanisms in ALS mouse models. Here, we studied the mRNA and protein expression of PINK1 and DJ-1 in postmortem brain and spinal cord tissue and muscle biopsy samples from ALS patients and controls and in brain, spinal cord, and gastrocnemius muscle of SOD1(G93A) ALS mice at different disease stages. We found significant decreases of PINK1 and DJ-1 mRNA levels in muscle tissue of SOD1(G93A) mice. Together with the significant decrease of PINK1 mRNA levels in human ALS muscle tissue, statistically nonsignificant reduction of DJ-1 mRNA levels, and reduced immunostaining for PINK1 in human ALS muscle, the results suggest potential pathophysiologic roles for these proteins in both mutant SOD1 transgenic mice and in sporadic ALS(G93A).

CDP-choline is not protective in the SOD1-G93A mouse model of ALS.

Important pathogenic factors in ALS include excitotoxicity and oxidative stress. Cytidine 5-diphosphocholine (CDP-choline) has recently been reported to have neuroprotective effects in animal models for neurodegenerative diseases, attributable to its anti-glutamatergic, anti-excitotoxic, anti-apoptotic and membrane-preserving properties. In this study we administered either CDP-choline or vehicle to transgenic SOD1-G93A mice daily via intraperitoneal (i.p.) injection starting before disease onset (day 30). By monitoring of survival, motor function, weight and general condition we examined possible therapeutic effects. Additional animals were used for histological studies to determine the effect of CDP-choline on motor neuron survival, astrocytosis and myelination in the spinal cord. Results showed that CDP-choline treatment modified neither the deterioration of general condition nor the loss of body weight. Survival of CDP-choline treated animals was not prolonged compared to vehicle treated controls. None of the behavioural motor function tests revealed differences between groups and no differences in motor neuron survival, astrocytosis or myelination were detected by histological analyses. In conclusion, our data from the transgenic mouse model do not strongly support further clinical validation of CDP-choline for the treatment of ALS.

Differential sirtuin expression patterns in amyotrophic lateral sclerosis (ALS) postmortem tissue: neuroprotective or neurotoxic properties of sirtuins in ALS?

BACKGROUND/AIMS: Sirtuins (SIRT1-7; class III histone deactylases) modulate fundamental mechanisms in age-related neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS). We assessed the expression levels of sirtuins in human postmortem ALS and control brain and spinal cord. METHODS AND RESULTS: By quantitative real-time PCR, a significant reduction of SIRT1 and SIRT2 was detected in homogenates of the primary motor cortex (white and gray matter), while there were no differences in spinal cord homogenates. When specifically analyzing mRNA and protein expression in the gray matter (cortical layers I-VI of the precentral gyrus, ventral/dorsal horn of the spinal cord) by in situ hybridization histochemistry and immunohistochemistry, we found increased levels of SIRT1, SIRT2 and SIRT5 in ALS which were significant for SIRT1 and SIRT5 mRNA in the spinal cord. CONCLUSION: Our results indicate a general reduction of SIRT1 and SIRT2 in ALS primary motor cortex, while in situ hybridization histochemistry and immunohistochemistry showed neuron-specific upregulation of SIRT1, SIRT2 and SIRT5, particularly in the spinal cord. Opposed effects have been described for SIRT1 and SIRT2: while SIRT1 activation is mainly associated with neuroprotection, SIRT2 upregulation is toxic to neuronal cells. Novel therapeutic approaches in ALS could therefore target SIRT1 activation or SIRT2 inhibition.

Speech therapy and communication device: impact on quality of life and mood in patients with amyotrophic lateral sclerosis.

Dysarthria has a drastic impact on the quality of life of ALS patients. Most patients suffering from dysarthria are offered speech therapy. Communication devices are prescribed less frequently. In the present study we investigated the impact of these therapeutic arrangements on quality of life in ALS patients. Thirty-eight ALS patients with dysarthria or anarthria, who underwent speech therapy and/or used communication devices answered three standardized questionnaires (Beck Depression Inventory - II (BDI), SF-36 Health Survey questionnaire (SF-36) and ALS Functional Rating Scale-revised (ALSFRS-R)) and were further interviewed about their experience with and benefit of speech therapy and communication devices. Most of the patients described a high impact of the communication device on their quality of life while the influence of speech therapy was rated less. By multiple regression analysis we confirmed an independent positive effect of communication device use on depression and psychological distress. In conclusion, communication systems improve or at least stabilize quality of life and mood in dysarthric ALS patients, and should be provided early in the disease course.

Decreased mRNA expression of PGC-1α and PGC-1α-regulated factors in the SOD1G93A ALS mouse model and in human sporadic ALS.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by selective motoneuron loss. Although the cause of ALS is unknown, oxidative stress, inflammation, and mitochondrial dysfunction have been identified as important components of its pathogenesis. Peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) plays a central role in the regulation of mitochondrial metabolism and biogenesis via activation of transcription factors, such as nuclear respiratory factors 1 and 2 and mitochondrial transcription factor A (Tfam). Alterations in PGC-1α expression and function have previously been described in models of Huntington and Alzheimer diseases. Moreover, the protective effects of PGC-1α have been shown in animal models of ALS. Levels of PGC-1α correlate with the number of acetylcholine receptor clusters in muscle. This is of particular interest because neurodegeneration in ALS may be a dying-back process. We investigated mRNA and protein expressions of PGC-1α and PGC-1α-regulated factors in the spinal cord and muscle tissues of SOD1 ALS mice and in ALS patients. We detected significant alterations in mRNA expression of PGC-1α and downstream factors with their earliest occurrence in muscle tissue. Our data provide evidence for a role of PGC-1α in mitochondrial dysfunction both in the ALS mouse model and in human sporadic ALS that is probably most relevant in the skeletal muscle.

Diabetes prevention by immunomodulatory FTY720 treatment in the LEW.1AR1-iddm rat despite immune cell activation.

The prevention of diabetes by the immunomodulatory agent FTY720 (fingolimod) was studied in the LEW.1AR1-iddm (IDDM) rat, an animal model of human type 1 diabetes. Immune cell subtypes and cytokine profiles in pancreatic islets, secondary lymphoid tissue, and serum were analyzed for signs of immune cell activation. Animals were treated with FTY720 (1 mg/kg body weight) for 40 d starting on d 50 of life. Changes in gene and protein expression of cytokines, CD8 markers, monocyte chemoattractant protein-1, inducible NO synthase, and caspase 3 were evaluated. Treatment with FTY720 prevented diabetes manifestation and islet infiltration around d 60 of life, the usual time of spontaneous diabetes development. On d 120, 30 d after the end of FTY720 therapy, diabetes prevention persisted. However, six of 12 treated animals showed increased gene expression of IL-1beta, TNF-alpha, and CD8 markers in pancreas-draining lymph nodes, indicating immune cell activation. In parallel, serum concentrations of these proinflammatory cytokines were increased. These six animals also showed macrophage infiltration without proinflammatory cytokine expression in a small minority (2-3%) of islets. Interestingly, regulatory T lymphocytes were significantly increased in the efferent vessels of the pancreas-draining lymph nodes only in animals without signs of immune cell activation but not in the rats with immune cell activation. This provides an indication for a lack of protective capacity in the animals with activated immune cells. Thus, FTY720 treatment prevented the manifestation of diabetes by promoting the retention of activated immune cells in the lymph nodes, thereby avoiding islet infiltration and beta-cell destruction by proinflammatory cytokines.