@article{WeselekKeinerFauseretal.2020, author = {Weselek, Grit and Keiner, Silke and Fauser, Mareike and Wagenf{\"u}hr, Lisa and M{\"u}ller, Julia and Kaltschmidt, Barbara and Brandt, Moritz D. and Gerlach, Manfred and Redecker, Christoph and Hermann, Andreas and Storch, Alexander}, title = {Norepinephrine is a negative regulator of the adult periventricular neural stem cell niche}, series = {Stem Cells}, volume = {38}, journal = {Stem Cells}, number = {9}, doi = {10.1002/stem.3232}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218250}, pages = {1188 -- 1201}, year = {2020}, abstract = {The limited proliferative capacity of neuroprogenitor cells (NPCs) within the periventricular germinal niches (PGNs) located caudal of the subventricular zone (SVZ) of the lateral ventricles together with their high proliferation capacity after isolation strongly implicates cell-extrinsic humoral factors restricting NPC proliferation in the hypothalamic and midbrain PGNs. We comparatively examined the effects of norepinephrine (NE) as an endogenous candidate regulator of PGN neurogenesis in the SVZ as well as the periventricular hypothalamus and the periaqueductal midbrain. Histological and neurochemical analyses revealed that the pattern of NE innervation of the adult PGNs is inversely associated with their in vivo NPC proliferation capacity with low NE levels coupled to high NPC proliferation in the SVZ but high NE levels coupled to low NPC proliferation in hypothalamic and midbrain PGNs. Intraventricular infusion of NE decreased NPC proliferation and neurogenesis in the SVZ-olfactory bulb system, while pharmacological NE inhibition increased NPC proliferation and early neurogenesis events in the caudal PGNs. Neurotoxic ablation of NE neurons using the Dsp4-fluoxetine protocol confirmed its inhibitory effects on NPC proliferation. Contrarily, NE depletion largely impairs NPC proliferation within the hippocampus in the same animals. Our data indicate that norepinephrine has opposite effects on the two fundamental neurogenic niches of the adult brain with norepinephrine being a negative regulator of adult periventricular neurogenesis. This knowledge might ultimately lead to new therapeutic approaches to influence neurogenesis in hypothalamus-related metabolic diseases or to stimulate endogenous regenerative potential in neurodegenerative processes such as Parkinson's disease.}, language = {en} } @article{KumarNaumannAigneretal.2015, author = {Kumar, Praveen and Naumann, Ulrike and Aigner, Ludwig and Wischhusen, Joerg and Beier, Christoph P and Beier, Dagmar}, title = {Impaired TGF-β induced growth inhibition contributes to the increased proliferation rate of neural stem cells harboring mutant p53}, series = {American Journal of Cancer Research}, volume = {5}, journal = {American Journal of Cancer Research}, number = {11}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-144262}, pages = {3436-3445}, year = {2015}, abstract = {Gliomas have been classified according to their histological properties. However, their respective cells of origin are still unknown. Neural progenitor cells (NPC) from the subventricular zone (SVZ) can initiate tumors in murine models of glioma and are likely cells of origin in the human disease. In both, p53 signaling is often functionally impaired which may contribute to tumor formation. Also, TGF-beta, which under physiological conditions exerts a strong control on the proliferation of NPCs in the SVZ, is a potent mitogen on glioma cells. Here, we approach on the crosstalk between p53 and TGF-beta by loss of function experiments using NPCs derived from p53 mutant mice, as well as pharmacological inhibition of TGF-beta signaling using TGF-beta receptor inhibitors. NPC derived from p53 mutant mice showed increased clonogenicity and more rapid proliferation than their wildtype counterparts. Further, NPC derived from p53\(^{mut/mut}\) mice were insensitive to TGF-beta induced growth arrest. Still, the canonical TGF-beta signaling pathway remained functional in the absence of p53 signaling and expression of key proteins as well as phosphorylation and nuclear translocation of SMAD2 were unaltered. TGF-beta-induced p21 expression could, in contrast, only be detected in p53\(^{wt/wt}\) but not in p53\(^{mut/mut}\) NPC. Conversely, inhibition of TGF-beta signaling using SB431542 increased proliferation of p53\(^{wt/wt}\) but not of p53\(^{mut/mut}\) NPC. In conclusion, our data suggest that the TGF-beta induced growth arrest in NPC depends on functional p53. Mutational inactivation of p53 hence contributes to increased proliferation of NPC and likely to the formation of hyperplasia of the SVZ observed in p53 deficient mice in vivo.}, language = {en} } @article{WilleSchuemannKreutzeretal.2015, author = {Wille, Michael and Sch{\"u}mann, Antje and Kreutzer, Michael and Glocker, Michael O and Wree, Andreas and Mutzbauer, Grit and Schmitt, Oliver}, title = {The proteome profiles of the olfactory bulb of juvenile, adult and aged rats - an ontogenetic study}, series = {Proteome Science}, volume = {13}, journal = {Proteome Science}, number = {8}, doi = {10.1186/s12953-014-0058-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-144073}, year = {2015}, abstract = {Background: In this study, we searched for proteins that change their expression in the olfactory bulb (oB) of rats during ontogenesis. Up to now, protein expression differences in the developing animal are not fully understood. Our investigation focused on the question whether specific proteins exist which are only expressed during different development stages. This might lead to a better characterization of the microenvironment and to a better determination of factors and candidates that influence the differentiation of neuronal progenitor cells. Results: After analyzing the samples by two-dimensional polyacrylamide gel electrophoresis (2DE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), it could be shown that the number of expressed proteins differs depending on the developmental stages. Especially members of the functional classes, like proteins of biosynthesis, regulatory proteins and structural proteins, show the highest differential expression in the stages of development analyzed. Conclusion: In this study, quantitative changes in the expression of proteins in the oB at different developmental stages (postnatal days (P) 7, 90 and 637) could be observed. Furthermore, the expression of many proteins was found at specific developmental stages. It was possible to identify these proteins which are involved in processes like support of cell migration and differentiation.}, language = {en} }