Ingela Nygren

Physical fitness, but not muscle strength, is a risk factor for death in amyotrophic lateral sclerosis at an early age

Background Amyotrophic lateral sclerosis (ALS) is a rare neurodegenerative disorder mainly characterised by motor symptoms. Extensive physical activity has been implicated in the aetiology of ALS. Differences in anthropometrics, physical fitness and isometric strength measured at 18–19 years were assessed to determine if they are associated with subsequent death in ALS. Method Data on body weight and height, physical fitness, resting heart rate and isometric strength measured at conscription were linked with data on death certificates in men born in 1951–1965 in Sweden (n=809 789). Physical fitness was assessed as a maximal test on an electrically braked bicycle ergometer. Muscle strength was measured as the maximal isometric strength in handgrip, elbow flexion and knee extension in standardised positions, using a dynamometer. Analyses were based on 684 459 (84.5%) men because of missing data. A matched case control study within this sample was performed. The population was followed until 31 December 2006, and 85 men died from ALS during this period. Results Weight adjusted physical fitness (W/kg), but not physical fitness per se, was a risk factor for ALS (OR 1.98, 95% CI 1.32 to 2.97), whereas resting pulse rate, muscle strength and other variables were not. Conclusions Physical fitness, but not muscle strength, is a risk factor for death at early age in ALS. This may indicate that a common factor underlies both fitness (W/kg) and risk of ALS.

Increased Red Blood Cell Polyamines in ALS and Parkinson's Disease

The polyamines spermidine (SPD) and spermine (SPM) are implicated in nerve cell degeneration and regeneration. Over 70% of circulating polyamines are associated with red blood cells (RBC). Against this background we have analysed RBC polyamines in two neurodegenerative disorders, amyotrophic lateral sclerosis (ALS) and Parkinsons disease (PD). Twenty patients with the sporadic form of ALS, 20 patients with PD, and 20 healthy controls were studied. The highest levels of SPD and SPM were found in the PD group where the mean values were 134 and 115%, respectively, above those of the controls. The patients with PD also presented the lowest levels of the SPD precursor, putrescine (PUTR). In the patients suffering from ALS the SPD and SPM mean levels were increased by 46 and 112%, respectively. The RBC SPD/SPM ratio in the patients suffering from PD was significantly elevated in comparison with that of ALS patient group, suggesting a different involvement of the polyamine system in these disorders. It is at present unknown if raised polyamine levels may contribute to induce the degeneration of susceptible neurons or if the increase represents a compensatory protective reaction, or simply an unspecific epiphenomenon.

Vitamin D deficiency in patients with myasthenia gravis and improvement of fatigue after supplementation of vitamin D3 : a pilot study

Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disorder. Vitamin D has important roles both in the autoimmune response and in skeletal muscles. We determined the levels of 25‐hydroxy vitamin D [25(OH)D] in patients with MG and in healthy subjects to determine whether vitamin D deficiency is present in MG and whether vitamin D supplementation has beneficial effects on fatigue.

Increased expression of glial cell line-derived neurotrophic factor mRNA in muscle biopsies from patients with amyotrophic lateral sclerosis.

The expression of glial cell line-derived neurotrophic factor (GDNF) mRNA and brain-derived neurotrophic factor (BDNF) mRNA were studied in muscle biopsies from five patients with amyotrophic lateral sclerosis (ALS), six patients with other neuromuscular diseases and eight healthy control persons. All five patients with ALS had higher GDNF mRNA expressions in their biopsies than the healthy control group (almost a three fold increase). Among the other patients only one, who had a rapidly progressing toxic polyneuropathy, showed a GDNF mRNA expression above those of the controls. The BDNF mRNA expressions in the biopsies from the ALS patients were in the same range as those from the healthy controls, although the mean value of the ALS patients was higher. The only biopsy that showed a markedly higher BDNF mRNA expression was taken from one patient with progressive muscular atrophy. These results suggest that increased GDNF mRNA expression in muscle is an unspecific response to ongoing denervation and that this response is maintained in ALS, at least temporarily. If increased GDNF mRNA in muscle proves to be a constant finding in ALS the rationale for the use of GDNF as a therapeutic agent in ALS must be questioned.

Alterations in muscle proteome of patients diagnosed with amyotrophic lateral sclerosis

UNLABELLED Amyotrophic lateral sclerosis (ALS) is a motor neuron disease characterized by progressive muscle paralysis. Currently clinical tools for ALS diagnostics do not perform well enough and their improvement is needed. The objective of this study was to identify specific protein alterations related to the development of ALS using tiny muscle biopsies. We applied a shotgun proteomics and quantitative dimethyl labeling in order to analyze the global changes in human skeletal muscle proteome of ALS versus healthy subjects for the first time. 235 proteins were quantified and 11 proteins were found significantly regulated in ALS muscles. These proteins are involved in muscle development and contraction, metabolic processes, enzyme activity, regulation of apoptosis and transport activity. In order to eliminate a risk to confuse ALS with other denervations, muscle biopsies of patients with postpolio syndrome and Charcot-Marie-Tooth disease (negative controls) were compared to those of ALS and controls. Only few proteins significantly regulated in ALS patients compared to controls were affected differently in negative controls. These proteins (BTB and kelch domain-containing protein 10, myosin light chain 3, glycogen debranching enzyme, transitional endoplasmic reticulum ATPase), individually or as a panel, could be selected for estimation of ALS diagnosis and development. BIOLOGICAL SIGNIFICANCE ALS is a devastating neurodegenerative disease, and luckily, very rare: only one to two people out of 100,000 develop ALS yearly. This fact, however, makes studies of ALS very challenging since it is very difficult to collect the representative set of clinical samples and this may take up to several years. In this study we collected the muscle biopsies from 12 ALS patients and compared the ALS muscle proteome against the one from control subjects. We suggested the efficient method for such comprehensive quantitative analysis by LC-MS and performed it for the first time using human ALS material. This gel- and antibody-free method can be widely applied for muscle proteome studies and has been used by us for revealing of the specific protein alterations associated with ALS.

The ALS/MND prevalence in Sweden estimated by riluzole sales statistics.

Objectives –  To determine whether sales statistics for riluzole can be used as a marker for the prevalence of amyotrophic lateral sclerosis (ALS)/motor neuron disease (MND) in Sweden.

July 2017 ENCALS statement on edaravone

Neurologists of the ENCALS centers throughout Europe have discussed the potential of edaravone as a new therapy for amyotrophic lateral sclerosis (ALS, Motor Neuron Disease, MND) at the ENCALS meeting, 18–20 May 2017, in Ljubljana, Slovenia. In May 2017, the US Food and Drug Administration (FDA) granted a license for the drug known as edaravone (licensed in Japan in 2015 as Radicut®) for the treatment of ALS in the United States (to be marketed as Radicava®). We are not aware of any official request from Mitsubishi Tanabe Pharma, the manufacturer of edaravone, to the European Medicines Agency (EMA) to register the drug for use in ALS in Europe. However, edaravone can be imported to Europe from Japan or the United States. The FDA approval of edaravone is based on a single positive clinical trial. The ENCALS neurologists were of the view that the outcome of this trial requires a balanced and considered interpretation when considering how best to advise those with ALS and their families. This study showed that edaravone may slow disease progression in ALS, but the disease-modifying effect was limited to a subgroup of ALS patients with distinct clinical characteristics. For ALS patients without those characteristics there is currently no evidence for a therapeutic benefit of edaravone.

Vitamin D deficiency in patients with primary immune-mediated peripheral neuropathies.

PURPOSE T cells are important in the immunopathology of immune-mediated peripheral neuropathies (PNP) and activated vitamin D regulates the immune response through increasing the amount of regulatory T cells. An association between vitamin D deficiency and polyneuropathy has been stipulated; hence we assessed whether patients with primary immune-mediated PNP have low vitamin D [25(OH)D] levels. METHODS Plasma levels of 25(OH)D were analyzed in 26 patients with primary immune-mediated PNP, 50 healthy matched blood donors and 24 patients with motor neuron disease (MND). INCAT score was assessed in patients with Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy. ALSFRS-R score was applied to MND patients and the modified Rankin (mRankin) scale compared disability among patient groups. RESULTS Mean 25(OH)D value in PNP patients was 40 ± 16 nmol/l, compared to 69 ± 21 nmol/l in healthy blood donors (p<0.001). MND patients had a higher mean 25(OH)D than PNP patients (59 ± 26 nmol/L; p=0.006) and comparable levels to healthy blood donors (p=0.15). Mean 25(OH)D value was not higher in PNP patients with pre-existing vitamin D3 supplementation of 800 IU/day (N=6; 35 ± 18 nmol/L) than in unsupplemented PNP patients (42 ± 16 nmol). INCAT score ranged from 0 to 10 (mean 3.5) and ALSFRS-R ranged from 11 to 44 (mean 31). mRankin score was more severe in MND patients (mean 3.5) compared to PNP patients (mean 2.1). CONCLUSIONS All patients with primary immune-mediated PNP were diagnosed with vitamin D deficiency and they had significantly lower 25(OH)D values than healthy control persons and MND patients. We suggest monitoring of vitamin D status in patients with autoimmune PNP, since immune cells are responsive to the ameliorative effects of vitamin D.

Monozygous twins with neuromuscular transmission defects at opposite sides of the motor endplate

Disorders affecting the postsynaptic side of the neuromuscular junction include autoimmune myasthenia gravis (MG) as well as some of the congenital myasthenic syndromes (CMS). Lambert‐Eaton myasthenic syndrome (LEMS) is an acquired autoimmune neuromuscular disorder in which autoantibodies are directed against the presynaptic calcium channels. Here we describe two monozygous twin brothers: case 1 was diagnosed with an indeterminate form of acquired postsynaptic neuromuscular junction defect at age 32 and case 2 with LEMS at age 47. Case 1 presented clinically with mild generalized myasthenic weakness, neurophysiological examination revealed disturbed neuromuscular transmission along with probable myositis and serum analysis regarding antibodies against the acetylcholine receptor and muscle‐specific tyrosine kinase was negative. Case 2 presented with proximal muscle fatigue accompanied by areflexia at rest and antibodies against the P/Q‐type voltage‐gated calcium channels were present. Neurophysiologically, case 2 had reduced baseline compound motor action potential amplitudes on neurography, decrement on low‐frequency repetitive nerve stimulation (RNS) and pathological increment on high frequency RNS. To our knowledge this is the first case report of its kind and adds an intriguing contrast to the more common diagnosis of CMS in monozygous twins.

Maintained regulation of polyamines in spinal cord from patients with amyotrophic lateral sclerosis

Levels of the polyamines putrescine, spermidine, and spermine were investigated in postmortem spinal cord from seven patients with amyotrophic lateral sclerosis (ALS) and seven control subjects. The method consisted of precolumn derivatization of the polyamines, followed by high-performance liquid chromatography (HPLC) analysis and fluorescence detection. The stability of the polyamines was examined in rat spinal cord during the interval of 0-36 h postmortem. The levels of putrescine, spermidine, and spermine increased by 32%, 15%, and 2%, respectively. Polyamine levels did not differ significantly between the ALS group and the control group, suggesting a maintained regulation of polyamines in the end stage of the disease. However, an effect of gender on the levels of spermidine and spermine was observed. Levels of spermidine and spermine in the ventral horn region of female ALS patients were significantly higher in comparison with the same region of the male ALS group (p<0.05). The female ALS group also presented significantly higher levels of spermidine in comparison with female controls (p<0.05).