Generation of astrocytes during the development of the mammalian spinal cord is poorly understood. Previously, we have shown that the glycoprotein of the extracellular matrix (ECM) tenascin-C (Tnc) modulates the expression territories of the patterning genes Nkx6.1 and Nkx2.2 in the developing ventral spinal cord, tunes the responsiveness of neural stem/progenitor cells towards the cytokines FGF2 and EGF and thereby promotes astrocyte maturation. In order to obtain further mechanistic insight into these processes, we have compared embryonic day-15 spinal cord neural progenitor cells (NPCs) from wild-type and Tnc knockout mice using continuous single-cell live imaging and cell lineage analysis in vitro. Tnc knockout cells displayed a significantly reduced rate of cell division both in response to FGF2 and EGF. When individual clones of dividing cells were investigated with regard to their cell lineage trees using the tTt tracking software, it appeared that the cell cycle length in response to growth factors was reduced in the knockout. Furthermore, when Tnc knockout NPCs were induced to differentiate by the removal of FGF2 and EGF glial differentiation was enhanced. We conclude that the constituent of the stem cell niche Tnc contributes to preserve stemness of NPCs.
Background: Gilles de la Tourette syndrome (TS) is a chronic neuropsychiatric disorder characterized by motor and vocal tics. First-line treatments for tics are antipsychotics and tic-specific behavioral therapies. However, due to a lack of trained therapists and adverse events of antipsychotic medication many patients seek alternative treatment options including cannabis. Based on the favorable results obtained from case studies on different cannabis-based medicines as well as two small randomized controlled trials using delta-9-tetrahydrocannabinol (THC), we hypothesize that the cannabis extract nabiximols can be regarded as a promising new and safe treatment strategy in TS.Objective: To test in a double blind randomized clinical trial, whether treatment with the cannabis extract nabiximols is superior to placebo in patients with chronic tic disorders.Patients and Methods: This is a multicenter, randomized, double-blind, placebo controlled, parallel-group, phase IIIb trial, which aims to enroll 96 adult patients with chronic tic disorders (TS or chronic motor tic disorder) across 6 centers throughout Germany. Patients will be randomized with a 2:1 ratio into a nabiximols and a placebo arm. The primary efficacy endpoint is defined as tic reduction of at least 30% (compared to baseline) according to the Total Tic Score of the Yale Global Tic Severity Scale (YGTSS-TTS) after 13 weeks of treatment. In addition, several secondary endpoints will be assessed including changes in different psychiatric comorbidities, quality of life, driving ability, and safety assessments.Discussion: This will be the first large, controlled study investigating efficacy and safety of a cannabis-based medicine in patients with TS. Based on available data using different cannabis-based medicines, we expect not only a reduction of tics, but also an improvement of psychiatric comorbidities. If the cannabis extract nabiximols is proven to be safe and effective, it will be a valuable alternative treatment option. The results of this study will be of high health-economic relevance, because a substantial number of patients uses cannabis (illegally) as self-medication.Conclusion: The CANNA-TICS trial will clarify whether nabiximols is efficacious and safe in the treatment of patients with chronic tic disorders.Clinical Trial Registration: This trial is registered at clinicaltrialsregister.eu (Eudra-CT 2016-000564-42) and clinicaltrials.gov (NCT03087201).
In the developing spinal cord neural stem and progenitor cells (NSPCs) secrete and are surrounded by extracellular matrix (ECM) molecules that influence their lineage decisions. The chondroitin sulfate proteoglycan (CSPG) DSD-1-PG is an isoform of receptor protein tyrosine phosphatase-beta/zeta (RPTPβ/ζ), a trans-membrane receptor expressed by NSPCs. The chondroitin sulfate glycosaminoglycan chains are sulfated at distinct positions by sulfotransferases, thereby generating the distinct DSD-1-epitope that is recognized by the monoclonal antibody (mAb) 473HD. We detected the epitope, the critical enzymes and RPTPβ/ζ in the developing spinal cord. To obtain insight into potential biological functions, we exposed spinal cord NSPCs to sodium chlorate. The reagent suppresses the sulfation of glycosaminoglycans, thereby erasing any sulfation code expressed by the glycosaminoglycan polymers. When NSPCs were treated with chlorate and cultivated in the presence of FGF2, their proliferation rate was clearly reduced, while NSPCs exposed to EGF were less affected. Time-lapse video microscopy and subsequent single-cell tracking revealed that pedigrees of NSPCs cultivated with FGF2 were strongly disrupted when sulfation was suppressed. Furthermore, the NSPCs displayed a protracted cell cycle length. We conclude that the inhibition of sulfation with sodium chlorate interferes with the FGF2-dependent cell cycle progression in spinal cord NSPCs.
We present here a longitudinal study determining the effects of two 3 week-periods of high intensity high volume interval training (HIHVT) (90 intervals of 6 s cycling at 250% maximum power, Pmax/24 s) on a cycle ergometer. HIHVT was evaluated by comparing performance tests before and after the entire training (baseline, BSL, and endpoint, END) and between the two training sets (intermediate, INT). The mRNA expression levels of myosin heavy chain (MHC) isoforms and markers of energy metabolism were analyzed in M. vastus lateralis biopsies by quantitative real-time PCR. In incremental tests peak power (Ppeak) was increased, whereas trueV˙O2peak was unaltered. Prolonged time-to-exhaustion was found in endurance tests with 65 and 80% Pmax at INT and END. No changes in blood levels of lipid metabolites were detected. Training-induced decreases of hematocrit indicate hypervolemia. A shift from slow MHCI/β to fast MHCIIa mRNA expression occurred after the first and second training set. The mRNA expression of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α), a master regulator of oxidative energy metabolism, decreased after the second training set. In agreement, a significant decrease was also found for citrate synthase mRNA after the second training set, indicating reduced oxidative capacity. However, mRNA expression levels of glycolytic marker enzyme glyceraldehyde-3-phosphate dehydrogenase did not change after the first and second training set. HIHVT induced a nearly complete slow-to-fast fiber type transformation on the mRNA level, which, however, cannot account for the improvements of performance parameters. The latter might be explained by the well-known effects of hypervolemia on exercise performance.
The differential diagnosis of acute visceral diseases is a challenging clinical problem. The older literature suggests that patients with acute visceral problems show segmental signs, such as hyperalgesia, skin resistance, or muscular defence, whose lateralization and segmental distribution may be used for differential diagnosis. This study aimed to investigate the lateralization and segmental distribution of spontaneous pain and segmental signs in acute visceral diseases. We recruited 208 emergency room patients that were presenting for acute medical problems. All patients underwent a structured 10-minute bodily examination to test for various segmental signs and were asked for spontaneous pain and segmental symptoms, such as nausea, meteorism, and urinary retention. We collected all findings as digital drawings on a tablet-PC. After the final diagnosis, patients were divided into groups according to the organ affected. Using statistical image analysis, we calculated average distributions of pain and segmental signs for the heart, lungs, stomach, liver/gallbladder, and kidneys/ureters analyzing their segmental distribution and lateralization. 85 of 110 patients with a single-organ problem reported pain, while 81 had at least one segmental sign, the most frequent being hyperalgesia (n=46), and muscle resistance (n=39). While the pain was distributed along the body midline, segmental signs for the heart, stomach and liver/gallbladder appeared mostly ipsilateral to the affected organ. An unexpectedly high number of patients (n=37) further showed ipsilateral mydriasis. The present study underlines the usefulness of including segmental signs in the bodily examination of patients with acute medical problems.
<b><i>Introduction:</i></b> Inflammation is a mechanism of the immune system that is part of the reaction to pathogens or injury. The central nervous system closely regulates inflammation via neuroendocrine or direct neuroimmune mechanisms, but our current knowledge of the underlying circuitry is limited. Therefore, we aimed to identify hypothalamic centres involved in sensing or modulating inflammation and to study their association with known large-scale brain networks. <b><i>Methods:</i></b> Using high-resolution functional magnetic resonance imaging (fMRI), we recorded brain activity in healthy male subjects undergoing experimental inflammation from intravenous endotoxin. Four fMRI runs covered key phases of the developing inflammation: pre-inflammatory baseline, onset of endotoxemia, onset of pro-inflammatory cytokinemia, and peak of pro-inflammatory cytokinemia. Using masked independent component analysis, we identified functionally homogeneous subregions of the hypothalamus, which were further tested for changes in functional connectivity during inflammation and for temporal correlation with tumour necrosis factor and adrenocorticotropic hormone serum levels. We then studied the connection of these inflammation-associated hypothalamic subregions with known large-scale brain networks. <b><i>Results:</i></b> Our results show that there are at least 6 hypothalamic subregions associated with inflammation in humans including the paraventricular nucleus, supraoptic nucleus, dorsomedial hypothalamus, bed nucleus of the stria terminalis, lateral hypothalamic area, and supramammillary nucleus. They are functionally embedded in at least 3 different large-scale brain networks, namely a medial frontoparietal network, an occipital-pericentral network, and a midcingulo-insular network. <b><i>Conclusion:</i></b> Measuring how the hypothalamus detects or modulates systemic inflammation is a first step to understand central nervous immunomodulation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.