Interaction of FGF-2 with IGF-1 and BDNF in stimulating Akt, ERK, and neuronal survival in hippocampal cultures.
The significance of multiple growth factors acting on individual neurons in the central nervous system is presently unclear. Cultured hippocampal neurons were used in the present study to compare the neurotrophic actions of fibroblast growth factor-2 (FGF-2) with the better characterized growth factors, insulin-like growth factor (IGF)-1 and brain-derived neurotrophic factor (BDNF). Additionally, cultures were utilized to identify possible interactions between FGF-2 and the other growth factors. Activation of the ERK and Akt pro-survival pathways, as well as neuronal survival itself, were studied. The maximal magnitude of Akt activation stimulated by FGF-2 was found to be similar to that stimulated by IGF-1 and BDNF. In contrast, IGF-1 was less effective at inducing ERK activation than were BDNF and FGF-2. All three agents were found to promote survival of neurons cultured under serum-free, low-insulin conditions, with FGF-2 surprisingly being significantly more effective than the other two peptides. Co-treatment with maximal concentrations of either IGF-1 or BDNF enhanced FGF-2-stimulated Akt and ERK activation. However, no enhancement of survival beyond that stimulated by FGF-2 was observed with co-treatment. These findings suggest that FGF-2 may play an important role in promoting the survival of hippocampal neurons. Additionally, an interesting dissociation was identified between the positive interaction of FGF-2 with both IGF-1 and BDNF in activating Akt and ERK, and the lack of enhancement of FGF-2-induced neuroprotection.
Johnson-Farley
Nadine N
NN
Department of Psychiatry, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, 125 Paterson Street, Suite 2200, New Brunswick, NJ 08901, USA.
Patel
Khushboo
K
Kim
Deborah
D
Cowen
Daniel S
DS
D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004622:Embryo, Mammalian; D004789:Enzyme Activation / Q000187:drug effects; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D006624:Hippocampus / Q000166:cytology*; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D009414:Nerve Growth Factors / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
D019208:Brain-Derived Neurotrophic Factor; D009414:Nerve Growth Factors; D016222:Fibroblast Growth Factor 2; D007334:Insulin-Like Growth Factor I; D051057:Proto-Oncogene Proteins c-akt; D048049:Extracellular Signal-Regulated MAP Kinases