Display Settings:

Format

Send to:

Choose Destination
J Pharmacol Exp Ther. 2006 Mar;316(3):1062-9. Epub 2005 Nov 11.

Cumulative activation of akt and consequent inhibition of glycogen synthase kinase-3 by brain-derived neurotrophic factor and insulin-like growth factor-1 in cultured hippocampal neurons.

Author information

  • 1Department of Psychiatry, UMDNJ-Robert Wood Johnson Medical School, 125 Paterson Street, New Brunswick, NJ 08901, USA.

Abstract

Brain-derived neurotrophic factor (BDNF) and insulin-like growth factor-1 (IGF-1) seem to play key roles in mediating neuronal plasticity in the hippocampus. In the current studies, we have used cultured hippocampal neurons to study possible interactions between the two growth factors in modulating neuronal signaling pathways. BDNF and IGF-1 were found to each effectively activate the neuroprotective Akt pathway, with the magnitude of activation being at least additive when cultures were simultaneously treated with supramaximal concentrations of peptides. Likewise, a cumulative inhibitory Akt-dependent phosphorylation of proapoptotic glycogen synthase kinase-3 was observed. Immunofluorescent studies demonstrated that a single population of neurons responded to BDNF and IGF-1. In contrast, the magnitude of BDNF-stimulated extracellular signal-regulated kinase (ERK) activation was found to be much greater than that of IGF-1-stimulated ERK, such that the difference in magnitude stimulated by BDNF in the presence and absence of IGF-1 did not reach statistical significance. Consistent with the observed agonist-stimulated activation of Akt, BDNF and IGF-1 were both found to act as neurotrophins, enhancing neuronal survival under low-insulin culture conditions. Maximal survival was achieved when both growth factors were present. These findings provide insight into the significance of multiple growth factors stimulating activation of ERK and Akt in the central nervous system. In some cases, the magnitude of activation required to elicit biological responses may be achieved only with a combination of compounds.

PMID:
16284277
[PubMed - indexed for MEDLINE]
Free full text

LinkOut - more resources

Full Text Sources

Other Literature Sources

PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for HighWire
    Loading ...
    Write to the Help Desk