Search results for "NERVE"
showing 10 items of 1683 documents
Cellular composition and organization of the spinal cord central canal during metamorphosis of the frogXenopus laevis
2017
Studying the cellular composition and morphological changes of cells lining the central canal during Xenopus laevis metamorphosis could contribute to understand postnatal development and spinal cord regeneration. Here we report the analysis of central canal cells at different stages during metamorphosis using immunofluorescence for protein markers expression, transmission and scanning electron microscopy and cell proliferation assays. The central canal was regionalized according to expression of glial markers, ultrastructure, and proliferation in dorsal, lateral, and ventral domains with differences between larvae and froglets. In regenerative larvae, all cell types were uniciliated, have a…
Injured Axons Instruct Schwann Cells to Build Constricting Actin Spheres to Accelerate Axonal Disintegration
2019
Summary: After a peripheral nerve lesion, distal ends of injured axons disintegrate into small fragments that are subsequently cleared by Schwann cells and later by macrophages. Axonal debris clearing is an early step of the repair process that facilitates regeneration. We show here that Schwann cells promote distal cut axon disintegration for timely clearing. By combining cell-based and in vivo models of nerve lesion with mouse genetics, we show that this mechanism is induced by distal cut axons, which signal to Schwann cells through PlGF mediating the activation and upregulation of VEGFR1 in Schwann cells. In turn, VEGFR1 activates Pak1, leading to the formation of constricting actomyosin…
Selective Brain Network and Cellular Responses Upon Dimethyl Fumarate Immunomodulation in Multiple Sclerosis
2019
Background: Efficient personalized therapy paradigms are needed to modify the disease course and halt gray (GM) and white matter (WM) damage in patients with multiple sclerosis (MS). Presently, promising disease-modifying drugs show impressive efficiency, however, tailored markers of therapy responses are required. Here, we aimed to detect in a real-world setting patients with a more favorable brain network response and immune cell dynamics upon dimethyl fumarate (DMF) treatment. Methods: In a cohort of 78 MS patients we identified two thoroughly matched groups, based on age, disease duration, disability status and lesion volume, receiving DMF (n = 42) and NAT (n = 36) and followed them ove…
Bi- and uniciliated ependymal cells define continuous floor-plate-derived tanycytic territories
2017
Multiciliated ependymal (E1) cells line the brain ventricles and are essential for brain homeostasis. We previously identified in the lateral ventricles a rare ependymal subpopulation (E2) with only two cilia and unique basal bodies. Here we show that E2 cells form a distinct biciliated epithelium extending along the ventral third into the fourth ventricle. In the third ventricle floor, apical profiles with only primary cilia define an additional uniciliated (E3) epithelium. E2 and E3 cells' ultrastructure, marker expression and basal processes indicate that they correspond to subtypes of tanycytes. Using sonic hedgehog lineage tracing, we show that the third and fourth ventricle E2 and E3 …
The LepR-mediated leptin transport across brain barriers controls food reward
2018
Objective Leptin is a key hormone in the control of appetite and body weight. Predominantly produced by white adipose tissue, it acts on the brain to inhibit homeostatic feeding and food reward. Leptin has free access to circumventricular organs, such as the median eminence, but entry into other brain centers is restricted by the blood–brain and blood–CSF barriers. So far, it is unknown for which of its central effects leptin has to penetrate brain barriers. In addition, the mechanisms mediating the transport across barriers are unclear although high expression in brain barriers suggests an important role of the leptin receptor (LepR). Methods We selectively deleted LepR in brain endothelia…
Molecular mechanisms mediating the neuroprotective role of the selective estrogen receptor modulator, bazedoxifene, in acute ischemic stroke: A compa…
2017
As the knowledge on the estrogenic system in the brain grows, the possibilities to modulate it in order to afford further neuroprotection in brain damaging disorders so do it. We have previously demonstrated the ability of the selective estrogen receptor modulator, bazedoxifene (BZA), to reduce experimental ischemic brain damage. The present study has been designed to gain insight into the molecular mechanisms involved in such a neuroprotective action by investigating: 1) stroke-induced apoptotic cell death; 2) expression of estrogen receptors (ER) ERα, ERβ and the G-protein coupled estrogen receptor (GPER); and 3) modulation of MAPK/ ERK1/2 and PI3K/Akt signaling pathways. For comparison, …
A novel mutation of WDR62 gene associated with severe phenotype including infantile spasm, microcephaly, and intellectual disability
2017
Abstract The autosomal recessive form of primary microcephaly (MCPH) is a rare disorder characterized by head circumference of at least 3 standard deviation below the mean. The MCPH exhibits genetic heterogeneity with thirteen loci (MCPH1-MCPH13) identified, and associated with variable degree of intellectual disability. It has been reported that WDR62 is the second causative gene of autosomal recessive microcephaly (MCPH2) playing a significant role in spindle formation and the proliferation of neuronal progenitor cells. We report a clinical feature, electroclinical findings, and clinical course of a patient with a severe phenotype of MCPH2 including microcephaly, refractory infantile spas…
Plasticity-Related Gene 1 Affects Mouse Barrel Cortex Function via Strengthening of Glutamatergic Thalamocortical Transmission
2016
Plasticity-related gene-1 (PRG-1) is a brain-specific protein that modulates glutamatergic synaptic transmission. Here we investigated the functional role of PRG-1 in adolescent and adult mouse barrel cortex both in vitro and in vivo. Compared with wild-type (WT) animals, PRG-1-deficient (KO) mice showed specific behavioral deficits in tests assessing sensorimotor integration and whisker-based sensory discrimination as shown in the beam balance/walking test and sandpaper tactile discrimination test, respectively. At P25-31, spontaneous network activity in the barrel cortex in vivo was higher in KO mice compared with WT littermates, but not at P16-19. At P16-19, sensory evoked cortical respo…
Compromised Neurotrophic and Angiogenic Regenerative Capability during Tendon Healing in a Rat Model of Type-II Diabetes
2017
Metabolic diseases such as diabetes mellitus type-II (DM-II) may increase the risk of suffering painful connective tissue disorders and tendon ruptures. The pathomechanisms, however, by which diabetes adversely affects connective tissue matrix metabolism and regeneration, still need better definition. Our aim was to study the effect of DM-II on expressional changes of neuro- and angiotrophic mediators and receptors in intact and healing Achilles tendon. The right Achilles tendon was transected in 5 male DM-II Goto-Kakizaki (GK) and 4 age-matched Wistar control rats. The left Achilles tendons were left intact. At week 2 post-injury, NGF, BDNF, TSP, and receptors TrkA, TrkB and Nk1 gene expre…
Neuroligin-2 Expression in the Prefrontal Cortex is Involved in Attention Deficits Induced by Peripubertal Stress
2016
Emerging evidence indicates that attention deficits, which are frequently observed as core symptoms of neuropsychiatric disorders, may be elicited by early life stress. However, the mechanisms mediating these stress effects remain unknown. The prefrontal cortex (PFC) has been implicated in the regulation of attention, including dysfunctions in GABAergic transmission, and it is highly sensitive to stress. Here, we investigated the involvement of neuroligin-2 (NLGN-2), a synaptic cell adhesion molecule involved in the stabilization and maturation of GABAergic synapses, in the PFC in the link between stress and attention deficits. First, we established that exposure of rats to stress during th…