Enhanced production and proteolytic degradation of insulin-like growth factor binding protein-2 in proliferating rat astrocytes

Journal of Neuroscience Research
Daniel ChesikJ De Keyser

Abstract

Insulin-like growth factors (IGFs) protect neurons, are important for oligodendrocyte survival and myelin production, and stimulate the proliferation of astrocytes. The effects of IGFs are regulated by a family of IGF binding proteins (IGFBPs). Astrocytes express predominantly IGFBP-2. In the present study, primary neonatal rat astrocytes were cultivated in a chemically defined medium to initiate a differentiated cell status. After stimulation with fetal calf serum, astrocytes became hypertrophic and increased proliferation. Western blot analysis of cell lysate of proliferating astrocytes displayed an increased expression of IGFBP-2. This finding was supported by immunocytochemical images. Semiquantitative polymerase chain reaction analysis demonstrated equal mRNA levels in both differentiated and proliferating astrocytes, suggesting that the increase in IGFBP-2 production in proliferating astrocytes was exerted at the translational level. Concentrated medium of proliferating cells, however, displayed lower levels of IGFBP-2 than differentiated cells. When recombinant IGFBP-2 was incubated with culture media, we found degradation in the medium of proliferating cells, but not in medium of differentiated cells. This degradation c...Continue Reading

References

Sep 1, 1992·Neurochemical Research·W T NortonC F Brosnan
Jan 1, 1992·Acta Neuropathologica·T YamadaP L McGeer
Jan 1, 1987·International Journal of Developmental Neuroscience : the Official Journal of the International Society for Developmental Neuroscience·F PerraudG Labourdette
Jun 1, 1980·The Journal of Cell Biology·K D McCarthy, J de Vellis
Sep 1, 1983·Brain Research·R S Morrison, J de Vellis
Sep 1, 1995·Developmental Biology·J Fok-SeangJ W Fawcett
Feb 1, 1995·Endocrine Reviews·J I Jones, D R Clemmons
Jul 1, 1994·Brain Pathology·L F Eng, R S Ghirnikar
Jun 1, 1996·The International Journal of Biochemistry & Cell Biology·K M KelleyR G Rosenfeld
Mar 21, 1998·Proceedings of the National Academy of Sciences of the United States of America·S A LoddickE B De Souza
Apr 17, 1998·Journal of Neuroscience Research·V W Wu, J P Schwartz
Sep 14, 1999·Brain Research Bulletin·J W Fawcett, R A Asher
May 29, 2000·American Journal of Physiology. Endocrinology and Metabolism·R C Baxter

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Citations

Aug 2, 2005·Pediatric Research·Anne ChettyHeber C Nielsen
Oct 27, 2009·Neuroscience Letters·Daniel Chesik, Jacques De Keyser
Jan 24, 2007·Neurobiology of Disease·Karin BorgesRaymond Dingledine
Mar 17, 2015·Frontiers in Endocrinology·Adam Pickard, Dennis J McCance
May 29, 2007·International Review of Neurobiology·Daniel ChesikJacques De Keyser

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