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Retroviruses including Human Endogenous Retroviruses (HERVs), contain a conserved region with highly immunomodulatory functions in the transmembrane proteins in envelope gene (env) named immunosuppressive domain (ISU). In this report, we demonstrate that Env59-GP3 peptide holds therapeutic potential in a mouse model of myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE). The results show that this specific HERV-H derived ISU peptide, but not peptide derived from another env gene HERV-K, decreased the development of EAE in C57BL/6 mice, accompanied by reduced demyelination and inhibition of inflammatory cells. Moreover, here we tested the effect of peptides on macrophages differentiation. The treatment with Env59-GPS peptide modulate the pro-inflammatory M1 profile and anti-inflammatory M2 macrophages, being shown by inhibiting inflammatory M1 hallmark genes/cytokines expression and enhancing expression of M2 associated markers. These results demonstrate that Env59-GP3 ISU peptide has therapeutic potential in EAE possibly through inducing the polarization of M2 macrophages and inhibiting inflammatory responses., (Copyright © 2018 Elsevier Inc. All rights reserved.)

We studied phenotype-genotype correlation in a group of Polish males with spinal and bulbar muscular atrophy (SBMA) and in female carriers. Eleven males with suspected SBMA phenotype and three suspected female carriers were examined. Male patients presented with the predominant signs of progressive, symmetrical distal limb weakness with amyotrophy, facial muscular weakness with orofacial fasciculations, nasal voice and slight dysphagia, gynaecomastia, decreased potency, as well as hand tremor and distal peripheral sensory disturbances in a few cases. One of the carriers presented with a 30-year history of fasciculations and minimal distal weakness and cramps in the legs, while the other two were asymptomatic. DNA analysis revealed expanded size of CAG repeats in Xq11-12 in the AR gene in 10 out of 11 men (range 45-52 CAG repeats) and in the women (range 46-48 CAG repeats). There was no correlation between CAG repeat size and the age of disease onset and duration of the disease. A rare, predominantly distal distribution of weakness and amyotrophy was found in our group of the SBMA patients (8 out of 11 cases) from three unrelated kindreds and also in the remaining two sporadic cases. The extended CAG repeats within families were stable.

Background and Purpose: A previous study showed that low triglyceride concentration predicts higher mortality after stroke. The aim of our study was to determine whether serum triglyceride level is associated with stroke severity on admission., Methods: 863 consecutive patients with acute ischemic stroke were included. Serum triglyceride level was measured within 36 hours after stroke onset. Stroke severity on admission was assessed using Scandinavian Stroke Scale (SSS). The patients were divided into 2 groups: those with severe stroke (SSS < or =25) and those with mild/moderate stroke (SSS >25)., Results: Patients with severe stroke had significantly lower serum triglyceride level than patients with mild/moderate stroke (1.4+/-0.6 versus 1.7+/-1.3 mmol/L). After adjusting for age, sex, atrial fibrillation, diabetes mellitus, obesity, and ischemic heart disease, patients with triglyceride >2.3 mmol/L had lower risk of severe stroke than those with triglyceride < or =2.3 mmol/L (OR: 0.58; 95% CI: 0.35 to 0.95)., Conclusions: Our results suggest that lower level of triglyceride is associated with the more severe stroke.

The name of Carpal Tunnel Syndrome (CTS) refers to a complex of symptoms resulting from the pressure exerted on the median nerve in the carpal tunnel area [81]. In most cases, it is not possible to establish CTS causes, and we diagnose idiopathic CTS. CTS is the most frequent pressure neuropathy. Typical clinical symptoms include sensory effects in the forms of pain paresthesia or hypesthesia, limited to the wrist area innervated by the median nerve, presence if Tinel's symptoms, or a positive Phalen's test. In more advance cases, doctors find motor symptoms displayed by difficulties in the performance of precise activities, grasp weakness or thenar muscle atrophy. In some patients, we observe autonomous symptoms, e.g. skin perspiration disorders (dry skin on thumb, index and middle fingers), or vasomotor disorders. The most essential for diagnosis confirmation are electrophysiological examinations, which evaluate the median nerve functions. Sometimes, imaging techniques are useful, e.g. ultrasound, MRI and CTS scanning of the wrist. The most effective form of idiopathic treatment of CTS is surgery.

Cerebral ischemia triggers interleukin-6 (IL-6) release into blood. IL-6 is a key mediator of acute phase reaction. Markers of acute phase reaction (C-reactive protein, fibrinogen, fever) have been linked to poor prognosis in stroke patients. Interleukin-6 soluble receptor (sIL-6R) can potentiate IL-6 pro-inflammatory activity. The aim of this study was to investigate the relationship between IL-6 and sIL-6R in stroke patients. Serum cytokine levels were measured in 18 stroke patients and 13 controls using the ELISA method. On the second day of stroke, IL-6 levels were significantly higher in stroke patients than in controls; sIL-6R levels did not differ significantly between groups. Three months after stroke, IL-6 levels did not differ significantly between groups; sIL-6R levels were significantly decreased in stroke patients when compared with that in controls and with levels in acute phase of stroke. Decreased sIL-6R early after stroke might reflect a regulatory mechanism attenuating inflammatory response.

Neuropathy, one of the most common diabetes complications, is characterized by highly variable clinical picture. It is not established what evaluation scheme should be applied in the assessment of patient regarding diabetic neuropathy. The validity of various laboratory tests in the diagnosis of diabetic neuropathy also remains unclear. This paper describes different clinical manifestations of diabetic neuropathy and presents the most important methods of assessment of patients with neuropathy suspected based on literature data and authors' observations. Authors highlighted the implications of different methods in diagnostic process. The most valid methods include physical evaluation, determination of vibration sensation and assessment of nerve conduction velocity. The autonomic functions tests have a special role allowing for the diagnosis of autonomic neuropathy.

TrkA is the receptor tyrosine kinase (RTK) for nerve growth factor (NGF) and stimulates NGF-dependent cell survival and differentiation in primary neurons and also differentiation of neuroblastomas and apoptosis of medulloblastomas. We have previously shown that aspartic acid and glutamic acid substitution (AspGlu and GluAsp) of the activation loop tyrosines in TrkA (Tyr(683) and Tyr(684)) supports NGF-independent neuritogenesis and cell survival in PC12 cell-derived nnr5 cells. In this study, the AspGlu and GluAsp mutant Trks have been analysed for their ability to support NGF-independent and NGF-dependent neuritogenesis, proliferation and cell signalling in the human neuroblastoma cell line, SY5Y. We find that the AspGlu and GluAsp mutant Trks support NGF-dependent, but not NGF-independent, autophosphorylation, neuritogenic responses and/or inhibit cell cycle progression. The NGF-dependent neuritogenic responses are lower for the mutant Trks (approximately 30-60% for AspGlu and 50-60% for GluAsp), relative to wild-type TrkA. While both the AspGlu and GluAsp mutant Trks support NGF-dependent transient phosphorylation of Shc, PLCgamma-1, AKT, FRS2, SH2B as well as prolonged MAP kinase activation, the GluAsp mutant induces stronger NGF-dependent tyrosine phosphorylation of FRS2 and SH2B, as well as a stronger reduction in bromodeoxyuridine (BrdU) incorporation. Collectively, these data suggest that neither absolute levels of receptor autophosphorylation, high levels of TrkA expression nor the activation of a specific signalling pathway is dominant and absolutely essential for neuritogenesis and cell cycle arrest of SY5Y cells.

It is difficult to establish predictors for diabetic neuropathy because no generally accepted criteria of its diagnosis exist. In previous investigations risk factors profiles for neuropathy differ markedly. The aim of this study was to assess risk predictors for diabetic neuropathy in relation to different criteria of its diagnosis. Ninety-five diabetic patients entered the study. The exclusion criteria included uremia, alcohol abuse and radiculopathy. Control group consisted of 43 healthy volunteers. All patients underwent the clinical assessment, instrumental evaluation of superficial and deep sensation, tests of cardiovascular autonomic function and nerve conduction studies. According to the performed assessment patients were classified into following groups: without neuropathy, suspicion of neuropathy, neuropathy confirmed in clinical examination, neuropathy confirmed in electrophysiological testing, autonomic neuropathy. Analysis showed that the most important predictors in patients with subjective symptoms were type 2 diabetes mellitus, diabetes duration and age of patients. When neuropathy was diagnosed according to the clinical examination, predictors included type 2 diabetesmellitus and duration of the disease. In the cases of neuropathy confirmed by electrophysiological studies and autonomic neuropathy, only diabetes duration appeared to be a significant predictor. Our study demonstrated that predictors for diabetic neuropathy varied in relation to different diagnostic criteria and where the most important predictor for all forms of neuropathy is duration of diabetes. This result indicates the need for frequent screening tests in patients with long duration of the disease, irrespective of its metabolic control, patients' age or type of diabetes.

The aim of the study was to assess dysarthria in ALS subjects using acoustic speech analysis. The study was performed in 47 definite or probable ALS patients aged 29-76 years (mean age 53.7 yr.) and in 30 age and sex matched healthy control subjects. Neurological examination showed 15 dysarthric ALS subjects. Acoustic speech analysis is a quantitative, computer-acoustic method estimating dysarthria and based on assessing of sound distance from speech sound tests. In both group the mean sound distance between chosen sounds was compared to a basic pattern and was measured on time-frequency computer acoustic analyses (delta f = 125 Hz, delta T = 9 ms, delta s = 0.5 dB). Our results demonstrated that all sounds were incorrect in all ALS subjects. These abnormalities were significantly increased in the dysarthric ALS subjects. The mean sound distances which separated ALS from control subjects is 0.2 (by Euclidian principle) in 4 out of 5 measured sounds. We suggest that it is possible to detect and measure dysarthria in ALS patients based on the acoustic speech analysis, also in the limb onset ALS subjects.

We demonstrate that the signaling adapter, Grb2, binds directly to the neurotrophin receptor tyrosine kinase, TrkA. Grb2 binding to TrkA is independent of Shc, FRS-2, phospholipase Cgamma-1, rAPS, and SH2B and is observed in in vitro binding assays, yeast two-hybrid assays, and in co-immunoprecipitation assays. Grb2 binding to TrkA is mediated by the central SH2 domain, requires a kinase-active TrkA, and is phosphotyrosine-dependent. By analyzing a series of rat TrkA mutants, we demonstrate that Grb2 binds to the carboxyl-terminal residue, Tyr(794), as well as to the activation loop tyrosines, Tyr(683) and Tyr(684). By using acidic amino acid substitutions of the activation loop tyrosines on TrkA, we can stimulate constitutive kinase activity and TrkA-Shc interactions but, importantly, abolish TrkA/Grb2 binding. Thus, in addition to providing the first evidence of direct Grb2 binding to the neurotrophin receptor, TrkA, these data provide the first direct evidence that the activation loop tyrosines of a receptor tyrosine kinase, in addition to their essential role in kinase activation, also serve a direct role in the recruitment of intracellular signaling molecules.

TrkA is the receptor tyrosine kinase (RTK) for nerve growth factor (NGF) and stimulates NGF-dependent cell survival and differentiation in primary neurons. TrkA expression in neuronal tumors also supports NGF-dependent differentiation of neuroblastomas and apoptosis of medulloblastomas. Phosphorylation of the activation loop tyrosines in RTK's are essential to activation as well as allosteric changes that facilitate substrate interaction and phosphorylation. Acidic amino acid substitution of the activation loop tyrosines in TrkA, Tyr683Tyr684, was performed to mimic the negative charges normally induced by ligand activation and receptor phosphorylation. A total of eight independent mutants containing single or double substitutions were generated for comparison. Herein, we demonstrate that acidic substitution of the activation loop tyrosines is sufficient to induce allosteric changes required for constitutive TrkA kinase activity as well as phosphorylation of TrkA signaling proteins such as Shc, PLCgamma-1, FRS-2 and erk1/2. The strongest constitutively active TrkA mutants, GluAsp and AspGlu, support NGF-independent neuritogenesis and cell survival to levels approximately 65 and 80-100%, respectively, of NGF-activated wild type TrkA. Thus, constitutively active TrkA may provide a useful strategy in future therapeutic approaches to limit the development and progression of neuronal tumors.

The cause of diabetic neuropathy remains unclear but several mechanisms have been considered. Hyperglycemia with all its metabolic and vascular consequences probably plays the main role. Metabolic consequences of hyperglicemia including increased level of sorbitol and fructose, myoinositol deficiency and Na+/K+ adenosine triphosphate deficiency alter the function of peripheral nerves and lead to an oxidative stress, which changes fatty acid metabolism. Chronic hyperglycemia is also responsible for abnormalities in microcirculation that could lead to local ischemia evoking many endothelial changes. There are also some genetic factors, impaired neurotrophic support and autoimmune damage that influence sensitivity to peripheral nerve damage in diabetes mellitus.

We have isolated a human cDNA for the signaling adapter molecule FRS-2/suc1-associated neurotrophic factor target and shown that it is tyrosine-phosphorylated in response to nerve growth factor (NGF) stimulation. Importantly, we demonstrate that the phosphotyrosine binding domain of FRS-2 directly binds the Trk receptors at the same phosphotyrosine residue that binds the signaling adapter Shc, suggesting a model in which competitive binding between FRS-2 and Shc regulates differentiation versus proliferation. Consistent with this model, FRS-2 binds Grb-2, Crk, the SH2 domain containing tyrosine phosphatase SH-PTP-2, the cyclin-dependent kinase substrate p13(suc1), and the Src homology 3 (SH3) domain of Src, providing a functional link between TrkA, cell cycle, and multiple NGF signaling effectors. Importantly, overexpression of FRS-2 in cells expressing an NGF nonresponsive TrkA receptor mutant reconstitutes the ability of NGF to stop cell cycle progression and to stimulate neuronal differentiation.

To investigate potential differences between the family of Trk receptors that might have differential consequences on cell signaling, we generated a rat TrkA homologue of the 14-amino acid kinase insert isoform of TrkC termed TrkAKi. Signal transduction by the TrkAKi receptor has been investigated and compared with the homologous signaling defective TrkC(Ki14) receptor. Herein, we demonstrate that TrkAKi receptors show a decrease in the absolute amount of kinase activity relative to wild-type TrkA, yet retain normal patterns of receptor tyrosine phosphorylation, as determined by phosphopeptide mapping studies, unlike TrkC(Ki14). nnr5 cell clones expressing TrkAKi receptors show a decrease in nerve growth factor (NGF)-mediated SHC tyrosine phosphorylation and a loss of high-affinity TrkA-SHC interaction comparable to those expressing TrkC(Ki14). Moreover, nnr5 cells expressing TrkAKi receptors fail to demonstrate NGF-dependent tyrosine phosphorylation of the signaling molecules phospholipase Cgamma-1, MAP kinase/ERK-1, and SNT. TrkAKi receptors internalize NGF comparable to wild-type TrkA, but do not stimulate neurite outgrowth. It is interesting that, unlike TrkC(Ki14), TrkAKi receptors retain phosphatidylinositol 3-kinase activity and nnr5 cells stably expressing TrkAKi receptors retain NGF-dependent cell survival under serum-free conditions. Lastly, TrkAKi receptors fail to stimulate three immediate-early genes (NGF1A, NGF1B, and c-fos), suggesting that these gene products are not required for NGF-dependent cell survival responses.