|
|
| Cytokine Database |
|
CILIARY NEUROTROPHIC FACTOR
LATEST LITERATURE
1: Journal of biomedical materials research. Part B, Applied biomaterials, 2010 Aug 24, 30(17)
Ciliary neurotrophic factor-coated polylactic-polyglycolic acid chitosan nerve conduit promotes peripheral nerve regeneration in canine tibial nerve defect repair.
[Abstract]A variety of nerve conduits incorporated with chemical and biological factors have been developed to further stimulate nerve regeneration. Although most of the nerve guides in studies are basically limited to bridge a short gap of nerve defect in rat models, it is vital to evaluate effects of conduits on nerve regeneration over distance greater than 20 mm, or more clinically relevant nerve gap lengths in higher mammals. In this study, a poly(lactide-co-glycolide) (PLGA) nerve conduit, treated with pulsed plasma and coated with ciliary neurotrophic factor (CNTF) as well as chitosan, was used to repair 25-mm-long canine tibial nerve defects in eighteen cross-bred dogs. The canines were randomly divided into three groups (n = 6), a 25-mm segment of the tibial nerve was removed and replaced by a PLGA/chitosan-CNTF nerve conduit, PLGA/chitoson conduit and autologous nerve grafts were performed as the control. The results were evaluated by general observation, eletromyogram testing, S-100 histological immunostaining, and image analysis at 3 months after operation. The histological results demonstrated that the PLGA/chitosan-CNTF conduits and PLGA/chitosan conduits were capable of leading the damaged axons through the lesioned area. Through the comparation of the three groups, the results in PLGA/chitosan-CNTF conduits group were better than that of PLGA/chitosan conduits group, while they were similar to autologous nerve grafts group. Therefore, CNTF-coated PLGA/chitosan nerve conduits could be an alternative artificial nerve conduit for nerve regeneration. (c) 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010.
2: Developmental neurobiology, 2010 Aug 16, 30(17)
Segregation of the classical transmitters norepinephrine and acetylcholine and the neuropeptide Y in sympathetic neurons: Modulation by CNTF or prolonged growth in culture.
[Abstract]Recent evidence has demonstrated that co-transmission from mammalian neurons is not uniquely achieved by co-storage and co-release of transmitters and co-transmitters from single varicosities, but also by the concurrent release of mediators segregated in separate synapses of individual neurons. An important question to be addressed is whether neurons show defined patterns of segregation or whether this is a plastic feature. We addressed this question by exploring the segregation pattern of the classical sympathetic transmitters norepinephrine (NE) and acetylcholine (ACh) and the co-transmitter neuropeptide Y (NPY) in sympathetic ganglionic neurons co-cultured with cardiac myocytes. Using antibodies against NPY and the vesicular NE and ACh transporters VMAT2 and VAChT we investigated the effect of ciliary neurotrophic factor (CNTF) or long (3 weeks) culture periods on the segregation of VMAT2, VAChT and NPY to separate varicosities. We found that while ganglionic neurons showed cell body co-expression of all the markers examined after 3 days, VMAT2 was segregated from VAChT in 43% of the VAChT-positive varicosities. In contrast, VMAT2 was only segregated from NPY in 16.3% of the NPY-positive varicosities. Co-transmitter segregation and VAChT expression, was potentiated by both CNTF and longer times in culture. We also found two types of varicosities: one was smaller and located further from neuronal somata, and the other was larger, proximal to neuronal somata, and had a higher level of segregation. These data demonstrate segregation of classical transmitters in sympathetic neurons and plasticity of neurotransmitter segregation. Finally, we discuss a possible functional correlate of segregation in sympathetic neurons. (c) 2010 Wiley Periodicals, Inc. Develop Neurobiol, 2010.
3: Molecular and cellular biology, 2010 Jun 28,
Sortilin facilitates signaling of CNTF and related helical type-1 cytokines targeting the gp130/LIFR{beta} heterodimer.
[Abstract]Sortilin is a member of the Vps10p-domain family of neuropeptide and neurotrophin binding neuronal receptors. The family members interact with and partly share a variety of ligands, and partake in intracellular sorting and protein transport as well as in transmembrane signaltransduction. Thus, Sortilin mediates transport of both neurotensin and nerve growth factor, and interacts with their respective receptors, to facilitate ligand-induced signaling. Here we report that the ciliary neurotrophic factor/CNTF, and related ligands targeting the established CNTF receptor-alpha, binds to Sortilin with high affinity. We find that Sortilin may have at least two functions; one is to provide rapid endocytosis and removal of CNTF, something which is not provided by the CNTF receptor-alpha, the other to facilitate CNTF signaling through the gp130/LIF receptor-beta heterodimeric complex. Interestingly, the latter function is independent of both the CNTF receptor-alpha and ligand binding to Sortilin, but appears to implicate a direct interaction with the LIF receptor-beta. Thus, Sortilin facilitates signaling of all helical type-1 cytokines that engages the gp130/LIF receptor-beta complex.
4: Die Pharmazie, 2010 Apr, 65(4)
Therapeutic effects of a recombinant mutant of the human ciliary neurotrophic factor in a mouse model of metabolic syndrome.
[Abstract]Metabolic syndrome (MS) is highly prevalent in developed countries and becoming a serious worldwide public health issue. In this study, we established a MS model by feeding male C57BL/6J mice with a high-fat diet (10%) for 18.5 weeks, studied the therapeutic effects of a recombinant mutant of the human ciliary neurotrophic factor (rhmCNTF) 0.1 (C-0.1) or 0.3 (C-0.3) mg x kg(-1) per day subcutaneously or pair feeding (PF, which mice were restricted to the same amount of food as eaten by C-0.3 treated mice) in MS mice. After 10 days treatment, rhmCNTF reduced obesity related indices, ameliorated glucose and lipid metabolism abnormality, and enhanced insulin sensitivity. In addition, liver function and antioxidant ability of MS mice were improved by rhmCNTF. Pair feeding revealed the same effects as C-0.3 on obesity related indices and insulin sensitivity, but aggravated hepatic steatosis and hepatic function. The results suggest that rhmCNTF could serve as an effective therapeutic agent for MS and related diseases.
5: Acta medica Okayama, 2010 Apr, 64(2)
Circulating levels of ciliary neurotrophic factor in normal pregnancy and preeclampsia.
[Abstract]Ciliary neurotrophic factor (CNTF) has been shown to decrease food intake in mouse models of obesity and to improve insulin sensitivity. It is well known that tight regulation of glucose metabolism is essential for successful gestational outcomes (e.g. fetal growth), and that abnormal insulin resistance is associated with preeclampsia (PE). To investigate the possibility that CNTF might be involved in the regulation of insulin resistance during pregnancy, circulating levels of CNTF were assessed in non-pregnant, normal pregnant, postpartum, and pregnant women with PE. Sera from healthy non-pregnant women (n10), pregnant women (n30:1st trimester;n10, 2nd trimester n10;3rd trimester;n10), postpartum women (n10), and patients with PE (n11) were studied with Western blotting. Circulating CNTF was detected by Western blotting, and the levels of CNTF in pregnant women were decreased as compared with those in non-pregnant women, and tended to decrease as pregnancy progressed. A significant decrease was found in PE as compared with normal pregnancy. Circulating CNTF might be associated with physiological and abnormal insulin resistance during pregnancy.
6: Advances in experimental medicine and biology, 2010, 664(1)
Function and Mechanism of CNTF/LIF Signaling in Retinogenesis.
[Abstract]Ciliary neurotrophic factor (CNTF) and leukemia inhibitory factor (LIF) exhibit multiple biological effects in the developing vertebrate retina. CNTF/LIF inhibits rod photoreceptor, and promotes bipolar cells and Muller glia differentiation. In addition, CNTF/LIF has been shown to have proliferative and apoptotic effects. Moreover, LIF also inhibits retinal vascular development. CNTF/LIF signaling components CNTFRalpha, LIFRbeta, gp130, and a number of STAT proteins are expressed in the retina. CNTF/LIF activates Jak-STAT, ERK, and Notch pathways during retinal development. Perturbation of CNTF induced signal transduction reveals that different combinations of CNTF/LIF signaling pathways regulate differentiation of retinal neurons and glia. Gene expression studies show that CNTF/LIF affects retinogenesis by regulating various genes involved in transcription, signal transduction, protein modification, apoptosis, protein localization, and cell ion homeostasis. Most past studies have deployed ectopic expression or addition of exogenous CNTF/LIF, thus further ana-lysis of mice with conditional mutations in CNTF/LIF signaling components will allow better understanding of in-vivo functions of CNTF/LIF associated signaling events in retinogenesis.
7: PloS one, 2010, 5(3)
CNTF Induces Regeneration of Cone Outer Segments in a Rat Model of Retinal Degeneration.
[Abstract]BACKGROUND: Cone photoreceptors are responsible for color and central vision. In the late stage of retinitis pigmentosa and in geographic atrophy associated with age-related macular degeneration, cone degeneration eventually causes loss of central vision. In the present work, we investigated cone degeneration secondary to rod loss in the S334ter-3 transgenic rats carrying the rhodopsin mutation S334ter. METHODOLOGY/PRINCIPAL FINDINGS: Recombinant human ciliary neurotrophic factor (CNTF) was delivered by intravitreal injection to the left eye of an animal, and vehicle to the right eye. Eyes were harvested 10 days after injection. Cone outer segments (COS), and cell bodies were identified by staining with peanut agglutinin and cone arrestin antibodies in whole-mount retinas. For long-term treatment with CNTF, CNTF secreting microdevices were implanted into the left eyes at postnatal day (PD) 20 and control devices into the right eyes. Cone ERG was recorded at PD 160 from implanted animals. Our results demonstrate that an early sign of cone degeneration is the loss of COS, which concentrated in many small areas throughout the retina and is progressive with age. Treatment with CNTF induces regeneration of COS and thus reverses the degeneration process in early stages of cone degeneration. Sustained delivery of CNTF prevents cones from degeneration and helps them to maintain COS and light-sensing function. CONCLUSIONS/SIGNIFICANCE: Loss of COS is an early sign of secondary cone degeneration whereas cell death occurs much later. At early stages, degenerating cones are capable of regenerating outer segments, indicating the reversal of the degenerative process. Sustained delivery of CNTF preserves cone cells and their function. Long-term treatment with CNTF starting at early stages of degeneration could be a viable strategy for preservation of central vision for patients with retinal degenerations.
8: The Journal of neuroscience : the official journal of the Society for Neuroscience, 2010 Feb 24, 30(8)
Transplantation of Ciliary Neurotrophic Factor-Expressing Adult Oligodendrocyte Precursor Cells Promotes Remyelination and Functional Recovery after SpinalCord Injury.
[Abstract]Demyelination contributes to the dysfunction after traumatic spinal cord injury (SCI). We explored whether the combination of neurotrophic factors and transplantation of adult rat spinal cord oligodendrocyte precursor cells (OPCs) could enhance remyelination and functional recovery after SCI. Ciliary neurotrophic factor (CNTF) was the most effective neurotrophic factor to promote oligodendrocyte (OL) differentiation and survival of OPCs in vitro. OPCs were infected with retroviruses expressing enhanced green fluorescent protein (EGFP) or CNTF and transplanted into the contused adult thoracic spinal cord 9 d after injury. Seven weeks after transplantation, the grafted OPCs survived and integrated into the injured spinal cord. The survival of grafted CNTF-OPCs increased fourfold compared with EGFP-OPCs. The grafted OPCs differentiated into adenomatus polyposis coli (APC(+)) OLs, and CNTF significantly increased the percentage of APC(+) OLs from grafted OPCs. Immunofluorescent and immunoelectron microscopic analyses showed that the grafted OPCs formed central myelin sheaths around the axons in the injured spinal cord. The number of OL-remyelinated axons in ventrolateral funiculus (VLF) or lateral funiculus (LF) at the injured epicenter was significantly increased in animals that received CNTF-OPC grafts compared with all other groups. Importantly, 75% of rats receiving CNTF-OPC grafts recovered transcranial magnetic motor-evoked potential and magnetic interenlargement reflex responses, indicating that conduction through the demyelinated axons in VLF or LF, respectively, was partially restored. More importantly, recovery of hindlimb locomotor function was significantly enhanced in animals receiving grafts of CNTF-OPCs. Thus, combined treatment with OPC grafts expressing CNTF can enhance remyelination and facilitate functional recovery after traumatic SCI.
9: Calcified tissue international, 2010 Feb 16, 88(4)
Ciliary Neurotrophic Factor Inhibits Bone Formation and Plays a Sex-Specific Role in Bone Growth and Remodeling.
[Abstract]Ciliary neurotrophic factor (CNTF) receptor (CNTFR) expression has been described in osteoblast-like cells, suggesting a role for CNTF in bone metabolism. When bound to CNTF, neuropoietin (NP), or cardiotrophin-like-cytokine (CLC), CNTFR forms a signaling complex with gp130 and the leukemia inhibitory factor receptor, which both play critical roles in bone cell biology. This study aimed to determine the role of CNTFR-signaling cytokines in bone. Immunohistochemistry detected CNTF in osteoblasts, osteocytes, osteoclasts, and proliferating chondrocytes. CNTFR mRNA was detected in primary calvarial osteoblasts and was upregulated during osteoblast differentiation. Treatment of osteoblasts with CNTF or CLC, but not NP, significantly inhibited mineralization and osterix mRNA levels. Twelve-week-old male CNTF ( -/- ) mice demonstrated reduced femoral length, cortical thickness, and periosteal circumference; but femoral trabecular bone mineral density (Tb.BMD) and tibial trabecular bone volume (BV/TV) were not significantly different from wild-type, indicating a unique role for CNTF in bone growth in male mice. In contrast, female CNTF ( -/- ) femora were of normal width, but femoral Tb.BMD, tibial BV/TV, trabecular number, and trabecular thickness were all increased. Female CNTF ( -/- ) tibiae also demonstrated high osteoblast number and mineral apposition rate compared to wild-type littermates, and this was intrinsic to the osteoblast lineage. CNTF is expressed locally in bone and plays a unique role in female mice as an inhibitor of trabecular bone formation and in male mice as a stimulus of cortical growth.
10: PloS one, 2010, 5(1)
Ciliary neurotrophic factor protects striatal neurons against excitotoxicity by enhancing glial glutamate uptake.
[Abstract]Ciliary neurotrophic factor (CNTF) is a potent neuroprotective cytokine in different animal models of glutamate-induced excitotoxicity, although its action mechanisms are still poorly characterized. We tested the hypothesis that an increased function of glial glutamate transporters (GTs) could underlie CNTF-mediated neuroprotection. We show that neuronal loss induced by in vivo striatal injection of the excitotoxin quinolinic acid (QA) was significantly reduced (by approximately 75%) in CNTF-treated animals. In striatal slices, acute QA application dramatically inhibited corticostriatal field potentials (FPs), whose recovery was significantly higher in CNTF rats compared to controls (approximately 40% vs. approximately 7%), confirming an enhanced resistance to excitotoxicity. The GT inhibitor DL-threo-beta-benzyloxyaspartate greatly reduced FP recovery in CNTF rats, supporting the role of GT in CNTF-mediated neuroprotection. Whole-cell patch-clamp recordings from striatal medium spiny neurons showed no alteration of basic properties of striatal glutamatergic transmission in CNTF animals, but the increased effect of a low-affinity competitive glutamate receptor antagonist (gamma-D-glutamylglycine) also suggested an enhanced GT function. These data strongly support our hypothesis that CNTF is neuroprotective via an increased function of glial GTs, and further confirms the therapeutic potential of CNTF for the clinical treatment of progressive neurodegenerative diseases involving glutamate overflow.
11: Nan fang yi ke da xue xue bao = Journal of Southern Medical University, 2009 Dec, 29(12)
[Bone marrow stromal cells transfected with ciliary neurotrophic factor gene ameliorates the symptoms and inflammation in C57BL/6 mice with experimental allergic encephalomyelitis.]
[Abstract]OBJECTIVE: To investigate the anti-inflammatory effect of bone marrow stromal cells (MSCs) transfected with recombinant adenovirus-mediated ciliary neurotrophic factor (CNTF) gene in C57BL/6 mice with experimental allergic encephalomyelitis (EAE). METHODS: An adenovirus vector containing CNTF gene Ad-CNTF-IRES-GFP was constructed and transfected in the MSCs (MSC-CNTF). After examination of CNTF expression, the transfected cells were transplanted in C57BL/6 mice with MOG 35-55-induced EAE, which were monitored for the changes in the symptoms scores. The levels of tumor necrosis factor-alpha (TNF-alpha), inteferon-gamma (IFN-gamma), interleukin-12P35 (IL-12P35), and IL-10 in the peripheral blood of the mice were detected, and the number of MSC-CNTF cells in the spleen and spinal cord was counted. CD3+ T cell infiltration and TNF-alpha and IFN-gamma expressions in the lesions were also observed after the cell transplantation. RESULTS: CNTF gene transfection resulted in significantly increased CNTF expression in the MSCs. The mice receiving MSC-CNTF transplantation exhibited significantly improved symptoms with shortened disease course and lessened disease severity. The cell transplantation also resulted in significantly decreased peripheral blood TNF-alpha levels, ameliorated CD3+T cell infiltrations and lowered TNF-alpha expression in the lesions, while the levels of IFN-gamma underwent no significant changes. CONCLSION: Transplantation of CNTF gene-transfected MSCs results in decreased peripheral blood TNF-alpha and IFN-gamma levels and reduced inflammatory cells, CD3-positive cells and TNF-alpha expression in the lesion of EAE, therefore providing better effect than MSCs in relieving the symptoms of EAE in mice.
12: Human molecular genetics, 2010 Jan 4, 99(1)
Ciliary neurotrophic factor-induced sprouting preserves motor function in a mouse model of mild spinal muscular atrophy.
[Abstract]Proximal spinal muscular atrophy (SMA) is caused by homozygous loss or mutation of the SMN1 gene on human chromosome 5. Depending on the levels of SMN protein produced from a second SMN gene (SMN2), different forms of the disease are distinguished. In patients with milder forms of the disease, type III or type IV SMA that normally reach adulthood, enlargement of motor units is regularly observed. However, the underlying mechanisms are not understood. Smn(+/-) mice, a mouse model of type III/IV SMA, reveal progressive loss of motor neurons and denervation of motor endplates starting at 4 weeks of age. Loss of spinal motor neurons between 1 month and 12 months reaches 40%, whereas muscle strength is not reduced. In these animals, amplitude of single motor unit action potentials in the gastrocnemic muscle is increased more than 2-fold. Confocal analysis reveals pronounced sprouting of innervating motor axons. As ciliary neurotrophic factor (CNTF) is highly expressed in Schwann cells, we investigated its role for a compensatory sprouting response and maintenance of muscle strength in this mouse model. Genetic ablation of CNTF results in reduced sprouting and decline of muscle strength in Smn(+/-) mice. These findings indicate that CNTF is necessary for a sprouting response and thus enhances the size of motor units in skeletal muscles of Smn(+/-) mice. This compensatory mechanism could guide the way to new therapies for this motor neuron disease.
13: The Journal of neuroscience : the official journal of the Society for Neuroscience, 2009 Nov 11, 29(45)
Neuroprotective and axon growth-promoting effects following inflammatory stimulation on mature retinal ganglion cells in mice depend on ciliary neurotrophic factor and leukemia inhibitory factor.
[Abstract]After optic nerve injury retinal ganglion cells (RGCs) normally fail to regenerate axons in the optic nerve and undergo apoptosis. However, lens injury (LI) or intravitreal application of zymosan switch RGCs into an active regenerative state, enabling these neurons to survive axotomy and to regenerate axons into the injured optic nerve. Several factors have been proposed to mediate the beneficial effects of LI. Here, we investigated the contribution of glial-derived ciliary neurotrophic factor (CNTF) to LI-mediated regeneration and neuroprotection using wild-type and CNTF-deficient mice. In wild-type mice, CNTF expression was strongly upregulated in retinal astrocytes, the JAK/STAT3 pathway was activated in RGCs, and RGCs were transformed into an active regenerative state after LI. Interestingly, retinal LIF expression was correlated with CNTF expression after LI. In CNTF-deficient mice, the neuroprotective and axon growth-promoting effects of LI were significantly reduced compared with wild-type animals, despite an observed compensatory upregulation of LIF expression in CNTF-deficient mice. The positive effects of LI and also zymosan were completely abolished in CNTF/LIF double knock-out mice, whereas LI-induced glial and macrophage activation was not compromised. In culture CNTF and LIF markedly stimulated neurite outgrowth of mature RGCs. These data confirm a key role for CNTF in directly mediating the neuroprotective and axon regenerative effects of inflammatory stimulation in the eye and identify LIF as an additional contributing factor.
14: Diabetes, 2009 Jan 9,
CNTF Stimulates Muscle Glucose Uptake by a PI3-Kinase Dependent Pathway that is Impaired with Obesity.
[Abstract]Objective. Ciliary neurotrophic factor (CNTF) reverses muscle insulin resistance by increasing fatty acid oxidation via gp130/LIF receptor signaling to the AMP-activated protein kinase (AMPK). CNTF also increases Akt signaling in neurons and adipocytes. As both Akt and AMPK regulate glucose uptake, we investigated muscle glucose uptake in response to CNTF signaling in lean and obese mice. Research Design and Methods. Mice were injected intraperitoneally with saline or CNTF and blood glucose monitored. The effects of CNTF on skeletal muscle glucose uptake and AMPK/Akt signaling were investigated in incubated soleus and EDL muscles from muscle specific AMPKalpha2 kinase-dead (KD), gp130DeltaSTAT, and lean and obese ob/ob and high-fat fed mice. The effect of C2-ceramide on glucose uptake and gp130-signaling was also examined. Results. CNTF reduced blood glucose, and increased glucose uptake in isolated muscles in a time and dose dependent manner with maximal effects after 30 min with 100 ng.ml(-1). CNTF increased Akt-S473 phosphorylation in soleus and EDL however; AMPK-T172 phosphorylation was only increased in soleus. Incubation of muscles from AMPK-KD and wild-type littermates with the PI3-kinase inhibitor LY-294002 demonstrated that PI3-kinase, but not AMPK, was essential for CNTF-stimulated glucose uptake. CNTF-stimulated glucose uptake and Akt-phosphorylation were substantially reduced in obesity (HFD and ob/ob) despite normal induction of gp130/AMPK signaling, effects also observed when treating myotubes with C2-ceramide. Conclusions. CNTF acutely increases muscle glucose uptake by a mechanism involving the PI3-kinase/Akt pathway, that does not require AMPK. CNTF stimulated glucose uptake is impaired in obesity induced insulin resistance and by ceramide.
15: Journal of neuroscience methods, 2009 Mar 30, 178(1)
Effects of ciliary neurotrophic factor and leukemia inhibiting factor on oxytocin and vasopressin magnocellular neuron survival in rat and mouse hypothalamic organotypic cultures.
[Abstract]Organotypic cultures of mouse and rat magnocellular neurons (MCNs) in the hypothalamo-neurohypophysial system (HNS) have served as important experimental models for the molecular and physiological study of this neuronal phenotype. However, it has been difficult to maintain significant numbers of the MCNs, particularly vasopressin MCNs, in these cultures for long periods. In this paper, we describe the use of the neurotrophic factors, leukemia inhibiting factor (LIF) and ciliary neurotrophic factor (CNTF) to rescue rat vasopressin (Avp)- and oxytocin (Oxt)-MCNs from axotomy-induced, programmed cell death in vitro. Quantitative data are presented for the efficacy of the LIF family of neurotrophic factors on the survival of MCNs in three nuclei, the paraventricular (PVN), supraoptic (SON), and accessory (ACC) nuclei in the mouse and rat hypothalamus.
16: Journal of neuroimmunology, 2009 Jan 3, 206(1-2)
Overexpression of CNTF in Mesenchymal Stem Cells reduces demyelination and induces clinical recovery in experimental autoimmune encephalomyelitis mice.
[Abstract]Human Mesenchymal Stem Cells (MSCs) were previously reported to ameliorate neuronal functional deficits in the MOG35-55-induced experimental autoimmune encephalomyelitis (EAE) mice by inducing T cell anergy. Human Ciliary neurotrophic factor (CNTF) recently was found to promote myelogenesis and reduce inflammation in CNTF-deficient EAE mice. We ectopically overexpressed CNTF in human MSCs to investigate its potential role in promoting remyelination and improving functional recovery in EAE mice. MSCs transfected by Ad-CNTF-IRES-EGFP (MSC-CNTF) were injected intravenously into EAE mice 10 days after the immunization. Neurological functional tests were scored daily by grading clinical signs (score 0-6). Immunofluorescence microscopy was used to detect MSC-CNTF in spinal cord. Expression of NG2, CNTF, and cleaved caspase-3 was measured by immunohistochemistry. CNTF expression was also analyzed by Western blot. Myelin was detected by Solochrome Cyanin staining. Our results found that CNTF concentration in MSC-CNTF cells was 20-fold higher than that in either MSC or Ad-EGFP-transfected MSCs (MSC-EGFP) in vitro. Mice receiving MSC-CNTF cells showed remarkable neuronal functional recovery: the cumulative clinical scores were significantly decreased, and the disease onset was statistically delayed. Mice receiving MSC-CNTF cells showed reduced TNF-alpha, IFN-gamma and increased the level of cytokine IL-10 in peripheral blood and a large number of MSC-CNTF cells were detected in the spleen, but were not detected in other organs such as lung, liver and kidney. In the lesions of these mice, 1) the number of cleaved caspase3-positive cells was significantly reduced; 2) MSC-CNTF- and NG2-positive cells were significantly increased; and 3) the expression of CNTF was dramatically increased. In addition, demyelination was significantly reduced in MSC-CNTF mice. These data indicated that MSC-CNTF may improve functional recovery in EAE mice, possibly by exerting their immunoregulatory activity, inhibiting inflammation, homing MSC-CNTF cells to the lesions, elevating CNTF expression, reducing demyelination, and stimulating oligodendrogenesis.
17: Investigative ophthalmology & visual science, 2008 Dec 5, 206(1-2)
CNTF over-expression leads to increased retinal ganglion cell survival in experimental glaucoma.
[Abstract]Purpose: To assess the neuroprotective effect of virally-mediated over-expression of ciliary derived neurotrophic factor (CNTF) and brain-derived neurotrophic factor (BDNF) in experimental rat glaucoma. Methods: Laser-induced glaucoma was produced in one eye of 224 Wistar rats after injection of adeno-associated viral vectors (type 2) containing either CNTF, BDNF or both, using saline injected eyes and uninjected glaucoma eyes as controls. IOP was measured with the TonoLab and semi-automated optic nerve axon counts were performed by masked observers. IOP exposure over time was adjusted in multivariate regression analysis to calculate the effect of CNTF and BDNF. Results: By multivariate regression, CNTF had a significant protective effect, with 15% less RGC axon death (p < 0.01). Both combined CNTF-BDNF and BDNF over-expression alone had no statistically significant improvement in RGC axon survival. By Western blot, there was a quantitative increase in CNTF and BDNF expression in retinas exposed to single viral vectors carrying each gene, but no increase with sequential injection of both vectors. Conclusion: These data confirm that CNTF can exert a protective effect in experimental glaucoma. The reason for a lack of observed effect with the BDNF overexpression groups is unclear, but may be a function of the level of neurotrophin expression achieved.
18: Investigative ophthalmology & visual science, 2008 Dec 5, 206(1-2)
Restoration of Functional CNTF Receptor {alpha} Subunit (CNTFR{alpha}) in Corneal Endothelial Cells in Stored Human Donor Corneas by Recombinant CNTFR{alpha}: Connexin-43 Up-regulation.
[Abstract]Purpose: CNTF is being tested in human clinical trials rescuing degenerating retina, whereas studies show that the CNTF-binding alpha-subunit of the CNTF receptor (CNTFRalpha) is released from injured tissues. Here, the recombinant human (rh) CNTFRalpha was shown to restore functional CNTFRalpha in human corneal endothelial (CE) cells that lost the endogenous CNTFRalpha during corneal storage. Methods: In CE cells of stored human donor corneas, endogenous CNTFRalphalevels were quantified (by Western blots), CNTF stimulation leading to up-regulation of connexin-43 was demonstrated, and the effectiveness of rhCNTFRalpha (8.3 nM) in augmenting the CNTF (0.83 nM) effect was tested: Paired human donor corneas were used either as vehicle- vs CNTF- or CNTF- vs (hCNTFRalpha+CNTF)- treated (24h , 37(o)C), followed by analysis of CE cell connexin-43 mRNA and protein by semi-quantitative RT-PCR and Western blots, respectively. After 90 min incubation with stored human corneas, rhCNTFRalpha incorporation into the CE membrane fraction was demonstrated by Western blots. Results: CE cell CNTFRalpha levels decreased as the corneal storage time increased. CE cell connexin-43 mRNA levels in CNTF-treated and (rhCNTFRalpha+ CNTF)-treated paired corneas averaged (mean+SEM) 0.26+0.08 and 0.58+0.21, respectively (p=0.029; eight pairs; storage time>== 25 days). rhCNTFRalpha augmentation was confirmed at the protein level. In corneas with short storage time <== 9days) that retained abundant endogenous CNTFRalpha, rhCNTFRalpha decreased the effectiveness of CNTF. rhCNTFRalpha was incorporated into CE membranes. Conclusion: rhCNTFRalpha acted as a surrogate to the lost endogenous membrane-bound CNTFRalpha in CNTF signaling, suggesting the potential of an adjuvant rhCNTFRalpha therapy in CNTF-therapy.
19: Journal of neurochemistry, 2009 Jan, 108(1)
CNTF-evoked activation of JAK and ERK mediates the functional expression of T-type Ca2+ channels in chicken nodose neurons.
[Abstract]Culture of chicken nodose neurons with CNTF but not BDNF causes a significant increase in T-type Ca(2+) channel expression. CNTF-induced channel expression requires 12 h stimulation to reach maximal expression and is not affected by inhibition of protein synthesis, suggesting the involvement of a post-translational mechanism. In this study, we have investigated the biochemical mechanism responsible for the CNTF-dependent stimulation of T-type channel expression in nodose neurons. Stimulation of nodose neurons with CNTF evoked a considerable increase in signal transducer and activator of transcription (STAT3) and extracellular signal-regulated kinase (ERK) phosphorylation. CNTF-evoked ERK phosphorylation was transient whereas BDNF-evoked activation of ERK was sustained. Pre-treatment of nodose neurons with the Janus tyrosine kinase (JAK) inhibitor P6 blocked STAT3 and ERK phosphorylation, whereas the ERK inhibitor U0126 prevented ERK activation but not STAT3 phosphorylation. Both P6 and U0126 inhibited the stimulatory effect of CNTF on T-type channel expression. Inhibition of STAT3 activation by the selective blocker stattic has no effect on ERK phosphorylation and T-type channel expression. These results indicate that CNTF-evoked stimulation of T-type Ca(2+) channel expression in chicken nodose neurons requires JAK-dependent ERK signaling. A cardiac tissue extract derived from E20 chicken heart was also effective in promoting T-type Ca(2+) channel expression and STAT3 and ERK phosphorylation. The ability of the heart extract to stimulate JAK/STAT and ERK activation was developmentally regulated. These findings provide further support to the idea that CNTF or a CNTF-like factor mediates normal expression of T-type channels.