Millipore Sigma Vibrant Logo
 

neuro cell signaling


1678 Results Búsqueda avanzada  
Mostrar
Productos (0)
Documentos (1,639)

Acote sus resultados Utilice los filtros siguientes para refinar su búsqueda

Tipo de documento

  • (1,639)
¿No encuentra lo que está buscando?
Póngase en contacto con
el Servicio de Atención
al Cliente

 
¿Necesita ayuda para encontrar un documento?
  • Differential roles of hyperglycemia and hypoinsulinemia in diabetes induced retinal cell death: evidence for retinal insulin resistance. 22046295

    Diabetes pathology derives from the combination of hyperglycemia and hypoinsulinemia or insulin resistance leading to diabetic complications including diabetic neuropathy, nephropathy and retinopathy. Diabetic retinopathy is characterized by numerous retinal defects affecting the vasculature and the neuro-retina, but the relative contributions of the loss of retinal insulin signaling and hyperglycemia have never been directly compared. In this study we tested the hypothesis that increased retinal insulin signaling and glycemic normalization would exert differential effects on retinal cell survival and retinal physiology during diabetes. We have demonstrated in this study that both subconjunctival insulin administration and systemic glycemic reduction using the sodium-glucose linked transporter inhibitor phloridzin affected the regulation of retinal cell survival in diabetic rats. Both treatments partially restored the retinal insulin signaling without increasing plasma insulin levels. Retinal transcriptomic and histological analysis also clearly demonstrated that local administration of insulin and systemic glycemia normalization use different pathways to counteract the effects of diabetes on the retina. While local insulin primarily affected inflammation-associated pathways, systemic glycemic control affected pathways involved in the regulation of cell signaling and metabolism. These results suggest that hyperglycemia induces resistance to growth factor action in the retina and clearly demonstrate that both restoration of glycemic control and retinal insulin signaling can act through different pathways to both normalize diabetes-induced retinal abnormality and prevent vision loss.
    Tipo de documento:
    Referencia
    Referencia del producto:
    SRI-13K
    Nombre del producto:
    Sensitive Rat Insulin RIA
  • GABA/glycine signaling during degeneration and regeneration of mouse hypoglossal nerves. 22325090

    In the adult central nervous system (CNS), GABA and glycine (Gly) are predominant inhibitory neurotransmitters, negatively regulating glutamatergic transmission. In the immature CNS, on the other hand, they act as trophic factors, mediating morphogenesis. In the present study, to investigate their involvement in axonal regeneration, we morphologically examined changes in their signaling in mouse hypoglossal nuclei during degeneration and regeneration of hypoglossal nerves. We found that (1) expression and localization of presynaptic elements were not changed, (2) localization of gephyrin, which anchors GABA and Gly receptors, was spread on the surface of motor neuron cell bodies and dendrites, (3) KCC2-expression markedly decreased, (4) choline acetyltransferase, which mediates acetylcholine-synthesis, immediately disappeared from the motor neurons, and (5) the synaptic cleft of both excitatory and inhibitory synapses became irregularly wider, in the hypoglossal nuclei of the sutured side after the operation. These changes gradually normalized during regeneration. These results suggested that synthesis of acetylcholine may be stopped in the motor neuron after axotomy. GABA/Gly may be normally released from presynaptic terminals, be spilled over the original synaptic cleft, be diffused into the neighboring space, bind to extrasynaptically localized receptors, and mediate depolarization of the membrane potential of motor neurons during degeneration and regeneration. Furthermore, it was suggested that GABA/Gly signaling in postsynaptic motor neurons went back to being immature after axotomy, and may play an important role in axonal regeneration.
    Tipo de documento:
    Referencia
    Referencia del producto:
    AB144
    Nombre del producto:
    Anti-Choline Acetyltransferase Antibody
  • Ligand-independent CXCR2 dimerization. 12888558

    Homo- and hetero-oligomerization have been reported for several G protein-coupled receptors (GPCRs). The CXCR2 is a GPCR that is activated, among the others, by the chemokines CXCL8 (interleukin-8) and CXCL2 (growth-related gene product beta) to induce cell chemotaxis. We have investigated the oligomerization of CXCR2 receptors expressed in human embryonic kidney cells and generated a series of truncated mutants to determine whether they could negatively regulate the wild-type (wt) receptor functions. CXCR2 receptor oligomerization was also studied by coimmunoprecipitation of green fluorescent protein- and V5-tagged CXCR2. Truncated CXCR2 receptors retained their ability to form oligomers only if the region between the amino acids Ala-106 and Lys-163 was present. In contrast, all of the deletion mutants analyzed were able to form heterodimers with the wt CXCR2 receptor, albeit with different efficiency, competing for wt/wt dimer formation. The truncated CXCR2 mutants were not functional and, when coexpressed with wt CXCR2, interfered with receptor functions, impairing cell signaling and chemotaxis. When CXCR2 was expressed with the AMPA-type glutamate receptor GluR1, CXCR2 dimerization was again impaired in a dose-dependent way, and receptor functions were prejudiced. In contrast, CXCR1, a chemokine receptor that shares many similarities with CXCR2, did not dimerize alone or with CXCR2 and when coexpressed with CXCR2 did not impair receptor signaling and chemotaxis. The formation of CXCR2 dimers was also confirmed in cerebellar neuron cells. Taken together, we conclude from these studies that CXCR2 functions as a dimer and that truncated receptors negatively modulate receptor activities competing for the formation of wt/wt dimers.
    Tipo de documento:
    Referencia
    Referencia del producto:
    AB1504
    Nombre del producto:
    Anti-Glutamate receptor 1 Antibody
  • Developmental dependence on NurRE and EboxNeuro for expression of pituitary proopiomelanocortin. 18388149

    Cell-specific expression of the pituitary proopiomelanocortin (POMC) gene depends on the combinatorial action of a large number of DNA-binding transcription factors (TFs). These include general and cell-restricted factors, as well as factors that act as effectors of signaling pathways. We have previously defined in the distal POMC promoter a composite regulatory element that contains targets for basic helix-loop-helix TFs conferring cell specificity and for NGFI-B orphan nuclear receptors that are responsive to CRH signaling and to glucocorticoid negative feedback. These factors act on neighboring regulatory elements, the Ebox(Neuro) and NurRE, respectively. Currently, the Ebox(Neuro) is thought to be the target of NeuroD1 during fetal development, but this factor may not account for activity in the adult pituitary; it is also unknown whether the NurRE and NGFI-B-related factors are active before establishment of the hypothalamic-pituitary portal system. In order to assess the importance of these regulatory elements and their cognate TFs throughout pituitary organogenesis and in the adult, we have assessed the activity of mutant POMC promoters in transgenic mice throughout development. These experiments indicate that the Ebox(Neuro) and cognate basic helix-loop-helix factors are required throughout development and in the adult gland, beyond expression of NeuroD1. Similarly, the data reveal sustained importance of the NurRE and its cognate factors throughout pituitary development. These data contrast the sustained dependence throughout development on the same regulatory elements with the highly dynamic patterns of TF expression and the modulation of their activity in response to signaling pathways.
    Tipo de documento:
    Referencia
    Referencia del producto:
    ABE991
    Nombre del producto:
    Anti-NeuroD1 Antibody
  • A compartmentalized microfluidic neuromuscular co-culture system reveals spatial aspects of GDNF functions. 25632161

    Bidirectional molecular communication between the motoneuron and the muscle is vital for neuromuscular junction (NMJ) formation and maintenance. The molecular mechanisms underlying such communication are of keen interest and could provide new targets for intervention in motoneuron disease. Here, we developed a microfluidic platform with motoneuron cell bodies on one side and muscle cells on the other, connected by motor axons extending through microgrooves to form functional NMJs. Using this system, we were able to differentiate between the proximal and distal effects of oxidative stress and glial-derived neurotrophic factor (GDNF), demonstrating a dying-back degeneration and retrograde transmission of pro-survival signaling, respectively. Furthermore, we show that GDNF acts differently on motoneuron axons versus soma, promoting axonal growth and innervation only when applied locally to axons. Finally, we track for the first time the retrograde transport of secreted GDNF from muscle to neuron. Thus, our data suggests spatially distinct effects of GDNF--facilitating growth and muscle innervation at axon terminals and survival pathways in the soma.
    Tipo de documento:
    Referencia
    Referencia del producto:
    AB1543P
    Nombre del producto:
    Anti-Synapsin I Antibody
  • Neuroprotective and anti-inflammatory effects of the flavonoid-enriched fraction AF4 in a mouse model of hypoxic-ischemic brain injury. 23251498

    We report here neuroprotective and anti-inflammatory effects of a flavonoid-enriched fraction isolated from the peel of Northern Spy apples (AF4) in a mouse of model of hypoxic-ischemic (HI) brain damage. Oral administration of AF4 (50 mg/kg, once daily for 3 days) prior to 50 min of HI completely prevented motor performance deficits assessed 14 days later that were associated with marked reductions in neuronal cell loss in the dorsal hippocampus and striatum. Pre-treatment with AF4 (5, 10, 25 or 50 mg/kg, p.o.; once daily for 3 days) produced a dose-dependent reduction in HI-induced hippocampal and striatal neuron cell loss, with 25 mg/kg being the lowest dose that achieved maximal neuroprotection. Comparison of the effects of 1, 3 or 7 doses of AF4 (25 mg/kg; p.o.) prior to HI revealed that at least 3 doses of AF4 were required before HI to reduce neuronal cell loss in both the dorsal hippocampus and striatum. Quantitative RT-PCR measurements revealed that the neuroprotective effects of AF4 (25 mg/kg; p.o.; once daily for 3 days) in the dorsal hippocampus were associated with a suppression of HI-induced increases in the expression of IL-1β, TNF-α and IL-6. AF4 pre-treatment enhanced mRNA levels for pro-survival proteins such as X-linked inhibitor of apoptosis and erythropoietin following HI in the dorsal hippocampus and striatum, respectively. Primary cultures of mouse cortical neurons incubated with AF4 (1 µg/ml), but not the same concentrations of either quercetin or quercetin-3-O-glucose or its metabolites, were resistant to cell death induced by oxygen glucose deprivation. These findings suggest that the inhibition of HI-induced brain injury produced by AF4 likely involves a transcriptional mechanism resulting from the co-operative actions of various phenolics in this fraction which not only reduce the expression of pro-inflammatory mediators but also enhance pro-survival gene signalling.
    Tipo de documento:
    Referencia
    Referencia del producto:
    MAB377
    Nombre del producto:
    Anti-NeuN Antibody, clone A60
  • Inflammation induces neuro-lymphatic protein expression in multiple sclerosis brain neurovasculature. 24124909

    Multiple sclerosis (MS) is associated with ectopic lymphoid follicle formation. Podoplanin+ (lymphatic marker) T helper17 (Th17) cells and B cell aggregates have been implicated in the formation of tertiary lymphoid organs (TLOs) in MS and experimental autoimmune encephalitis (EAE). Since podoplanin expressed by Th17 cells in MS brains is also expressed by lymphatic endothelium, we investigated whether the pathophysiology of MS involves inductions of lymphatic proteins in the inflamed neurovasculature.We assessed the protein levels of lymphatic vessel endothelial hyaluronan receptor and podoplanin, which are specific to the lymphatic system and prospero-homeobox protein-1, angiopoietin-2, vascular endothelial growth factor-D, vascular endothelial growth factor receptor-3, which are expressed by both lymphatic endothelium and neurons. Levels of these proteins were measured in postmortem brains and sera from MS patients, in the myelin proteolipid protein (PLP)-induced EAE and Theiler's murine encephalomyelitis virus (TMEV) induced demyelinating disease (TMEV-IDD) mouse models and in cell culture models of inflamed neurovasculature.Intense staining for LYVE-1 was found in neurons of a subset of MS patients using immunohistochemical approaches. The lymphatic protein, podoplanin, was highly expressed in perivascular inflammatory lesions indicating signaling cross-talks between inflamed brain vasculature and lymphatic proteins in MS. The profiles of these proteins in MS patient sera discriminated between relapsing remitting MS from secondary progressive MS and normal patients. The in vivo findings were confirmed in the in vitro cell culture models of neuroinflammation.
    Tipo de documento:
    Referencia
    Referencia del producto:
    AB1875
  • Distribution and synaptic localization of nicotinic acetylcholine receptors containing a novel alpha7 subunit isoform in embryonic rat cortical neurons. 15531097

    Neuronal nicotinic acetylcholine receptors (nAChRs) containing the alpha7 subunit isoform, alpha7-2 (alpha7-2-nAChRs), have previously been found to form functional homopentameric channels that desensitize slowly and bind alpha-bungarotoxin (alphaBgt) in a rapidly reversible manner. This isoform incorporates a novel cassette exon in the extracellular, ligand binding domain of the native receptor. Although this alpha7 subunit isoform has been detected in peripheral ganglia as well as in the central nervous system, little is known about the cellular function of alpha7-2-nAChRs. Co-localization immunocytochemical studies were conducted in an embryonic rat cultured cortical neuron model using a polyclonal antibody (Ab 87) raised against the amino acid sequence of the cassette exon, in combination with (1) an antibody that recognizes all known alpha7-nAChRs, (2) alphaBgt, and (3) antibodies directed against multiple cellular markers. The pattern of alpha7-2-nAChR expression was consistent with alpha7 staining in general, based on co-distribution of mAb319 and alphaBgt signals. However, alpha7-2-nAChRs clearly represent a distinct subset of alpha7 receptors. The alpha7-2-nAChR subtype was found throughout the cell-soma surface and was localized to a subpopulation of dendrites. Punctate staining characteristic of synaptic alpha7-2 targeting was observed at post-synaptic densities and intermittently at pre-synaptic locations. The alpha7-2 subunit was expressed on both GABAergic and non-GABAergic neurons. These studies reveal that receptors containing the alpha7-2 subunit constitute a subpopulation of alpha7-nAChRs and likely participate in cell-to-cell signaling in developing synapses of central neurons.
    Tipo de documento:
    Referencia
    Referencia del producto:
    Múltiplo
    Nombre del producto:
    Múltiplo
  • Common partner Smad-independent canonical bone morphogenetic protein signaling in the specification process of the anterior rhombic lip during cerebellum development. 23459943

    Bone morphogenetic protein (BMP) signaling is critical for cerebellum development. However, the details of receptor regulated-Smad (R-Smad) and common partner Smad (Co-Smad, or Smad4) involvement are unclear. Here, we report that cerebellum-specific double conditional inactivation of Smad1 and Smad5 (Smad1/5) results in cerebellar hypoplasia, reduced granule cell numbers, and disorganized Purkinje neuron migration during embryonic development. However, single conditional inactivation of either Smad1 or Smad5 did not result in cerebellar abnormalities. Surprisingly, conditional inactivation of Smad4, which is considered to be the central mediator of canonical BMP-Smad signaling, resulted only in very mild cerebellar defects. Conditional inactivation of Smad1/5 led to developmental defects in the anterior rhombic lip (ARL), as shown by reduced cell proliferation and loss of Pax6 and Atoh1 expression. These defects subsequently caused the loss of the nuclear transitory zone and a region of the deep cerebellar nuclei. The normal maturation of the remaining granule cell precursors in the external granular layer (EGL) suggests Smad1/5 signaling is required for the specification process in ARL but not for the subsequent EGL development. Our results demonstrate functional redundancy for Smad1 and Smad5 but functional discrepancy between Smad1/5 and Smad4 during cerebellum development.
    Tipo de documento:
    Referencia
    Referencia del producto:
    Múltiplo
    Nombre del producto:
    Múltiplo
  • Nkx2-2as Suppression Contributes to the Pathogenesis of Sonic Hedgehog Medulloblastoma. 29229597

    Aberrant Hedgehog signaling and excessive activation of the Gli family of transcriptional activators are key drivers of medulloblastoma (MB), the most common human pediatric brain malignancy. MB originates mainly from cerebellar granule neuron progenitors (CGNP), but the mechanisms underlying CGNP transformation remain largely obscure. In this study, we found that suppression of the noncoding RNA Nkx2-2as promoted Sonic Hedgehog (Shh)-potentiated MB development. Nkx2-2as functioned as a competing endogenous RNA against miR-103 and miR-107, sequestering them and thereby derepressing their tumor suppressive targets BTG2 and LATS1 and impeding cell division and migration. We also found that Nkx2-2as tethered miR-548m and abrogated its LATS2 targeting activity. Shh signaling impaired Nkx2-2as expression by upregulating the transcriptional repressor FoxD1. In clinical specimens of Shh-subgroup MB, we validated coordinated expression of the aforementioned proteins. Notably, exogenous expression of Nkx2-2as suppressed tumorigenesis and prolonged animal survival in MB mouse models. Our findings illuminate the role of noncoding RNAs in Hedgehog signaling and MB occurrence, with implications for identifying candidate therapeutic targets for MB treatment.Significance: These findings illuminate the role of noncoding RNAs in Hedgehog signaling and an interplay between the Hedgehog and Hippo pathways in medulloblastoma pathogenesis. Cancer Res; 78(4); 962-73. ©2017 AACR.
    Tipo de documento:
    Referencia
    Referencia del producto:
    17-701
    Nombre del producto:
    EZ-Magna RIP™ RNA-Binding Protein Immunoprecipitation Kit