Brain Derived Neurotrophic Factor Regulates Müller Cell Survival via MAPK and PI3K Pathways

Simple item page
dc.contributor.advisorAgarwal, Neeraj
dc.contributor.committeeMemberWordinger, Robert J.
dc.contributor.committeeMemberPang, Iok-Hou
dc.creatorTaylor, Sara A.
dc.date.accessioned2019-08-22T21:21:51Z
dc.date.available2019-08-22T21:21:51Z
dc.date.issued2003-05-01
dc.date.submitted2014-04-03T09:42:06-07:00
dc.description.abstractTaylor, Sara A., Brain Derived Neurotrophic Factor Regulates Müller Cell Survival via MAPK and PI3K Pathways. Master of Science (Biomedical Sciences), January, 2003, 112 pp., 4 tables, 39 illustrations, bibliography, 68 titles. Purpose: Glutamate has been implicated in many pathologies affecting the Central Nervous System including those in the retina, but the exact nature of the role of glutamate in neuronal degeneration remains unclear. In the retina. Müller cells are resistant to glutamate insults that are normally toxic to other cells of the retina, however the molecular and biochemical mechanisms that control their death or survival are not well understood. We used a series of pharmacological inhibitors and molecular biology agents on cultured Müller cells to dissect two key signaling pathways normally involved in cell survival, the Mitogen Activated Protein Kinase – Extracellularly Regulated Kinase (MAPK(ERK) pathway and the Phosphatidylinositide 3 Kinase (PI3K) pathway. Since preliminary data in our laboratory showed that Müller cells upregulate their secretion of neurotrophins including Brain Derived Growth Factor (BDNF) in response to glutamate treatment, we also examined the effect of BDNF on the activation of these two signaling pathways. Methods: Early passaged Müller cells were treated with various concentrations (5 nM -50 μM) of inhibitions of the MAPK(ERK) pathway (GW5074, U0126, and PD98059) or with various concentrations (1-50 μM) of inhibitors of the PI3K pathway (LY294002 or Akt inhibitor) in the presence and absence of 50 ng/ml of BDNF for 24 hours. These experiments were repeated in Müller cells transfected with either NFκB or Bc12 DNA. Cell cultures were then analyzed for surviving cells with an MTS/PMS assay, a colorametric method for determining the number of viable cells in a proliferation assay. Results: The MAPK (ERK) inhibitors PD98059 and GW5074 both resulted in decrease in Müller cell survival. PD98059 did not decrease Müller cell survival until concentrations were high enough to suppress ERK2 phosphorylation. Müller cells transfected with NFκB or Bc12 DNA were able to resist treatment with concentrations of PD98059 that reduced cell number in untransfected cells. The PI3K inhibitor LY294002 also resulted in significant decreases in Müller cell survival in both untransfected cells and cells transfected with NFκB or Bc12 DNA. Treatment with an inhibitor farther down in the PI3K pathway, Akt inhibitor, did not significantly decrease Müller cell survival. Finally, BDNF was not able to increase cell survival in Müller cells treated with PD98059 or U0126, although it did increase the survival of cells treated wit GW5074. BDNF was also able to reverse the decrease in cell survival caused by LY294002 in both untransfected Müller cells or Müller cells transfected with NFκB or Bc12 DNA. Conclusions: Our data shows that Mitogen Activated Protein Kinase – Extracellularly Regulated Kinase (MAPK(ERK) and Phosphatidylinositide 3 Kinase (PI3K) are both essential for Müller cell survival. There is modulation between the pathways and they may interconnected far upstream at a protein previously associated with only the MAPK(ERK) pathway. These results are consistent with a role for both pathways in Müller cell survival.
dc.format.mimetypeapplication/pdf
dc.identifier.urihttps://hdl.handle.net/20.500.12503/29275
dc.language.isoen
dc.provenance.legacyDownloads0
dc.subjectCell Anatomy
dc.subjectCell and Developmental Biology
dc.subjectCell Biology
dc.subjectCells
dc.subjectCellular and Molecular Physiology
dc.subjectDevelopmental Biology
dc.subjectDevelopmental Neuroscience
dc.subjectGenetics and Genomics
dc.subjectImmunity
dc.subjectImmunology and Infectious Disease
dc.subjectLife Sciences
dc.subjectMedical Cell Biology
dc.subjectMedical Neurobiology
dc.subjectMedicine and Health Sciences
dc.subjectMolecular and Cellular Neuroscience
dc.subjectNeuroscience and Neurobiology
dc.subjectOther Cell and Developmental Biology
dc.subjectBrain-derived neurotrophic factor
dc.subjectMüller cell survival
dc.subjectMAPK
dc.subjectPI3K
dc.subjectpathways
dc.subjectglutamate
dc.subjectcentral nervous system
dc.subjectretina
dc.subjectneuronal degeneration
dc.subjectmitogen activated protein kinase
dc.subjectphosphatidylinositide 3 kinase
dc.subjectbrain derived growth factor
dc.subjectBDNF
dc.subjectGW5074
dc.subjectU0126
dc.subjectPD98059
dc.subjectNFκB
dc.subjectBc12 DNA
dc.subjectextracellularly regulated kinase
dc.titleBrain Derived Neurotrophic Factor Regulates Müller Cell Survival via MAPK and PI3K Pathways
dc.typeThesis
dc.type.materialtext
thesis.degree.departmentGraduate School of Biomedical Sciences
thesis.degree.disciplineBiomedical Sciences
thesis.degree.grantorUniversity of North Texas Health Science Center at Fort Worth
thesis.degree.nameMaster of Science

Files

Original bundle

Now showing 1 - 1 of 1
Thumbnail Image
Name:
Taylor_BrainDerivedNeurotrophicFactor.pdf
Size:
34.58 MB
Format:
Adobe Portable Document Format
Download

Collections

School of Biomedical Sciences
Theses and Dissertations