Astroglial-conditioned media and growth factors modulate proliferation and differentiation of astrocytes in primary culture.
Astroglial conditioned media (ACM) influence the development and maturation of cultured nerve cells and modulate neuron-glia interaction. To clarify mechanisms of astroglial cell proliferation/differentiation in culture, incorporation of [methyl-3H]-thymidine or [5,6-3H]-uridine in cultured astrocytes was assessed. Cultures were pre-treated with epidermal growth factor (EGF), insulin (INS), insulin-like growth factor-I (IGF-I), and basic fibroblast growth factor (bFGF) and subsequently with ACM. DNA labeling revealed a marked stimulatory effect of ACM from 15 days in vitro (DIV) cultures in 30 DIV astrocytes after 12 h pre-treatment with growth factors. The main effects were found after INS or EGF pre-treatment in 30 DIV cultures. ACM collected from 15 or 60 or 90 DIV increased RNA labeling of 15 and 30 DIV astrocyte cultures, being the highest value that of 30 DIV cultures added with ACM from 90 DIV. The findings of increased DNA labeling after EGF or INS pre-treatment in 30 DIV cultures, followed by addition of ACM from 15 DIV cultures, suggest that these phenomena may depend by extra cellular signal-regulated kinase 1 (ERK1) activation.
Bramanti
Vincenzo
V
Section of Biochemistry and Molecular Biology, Department of Chemical Sciences, University of Catania, Viale Andrea Doria, 6, Catania, Italy.
Campisi
Agata
A
Tomassoni
Daniele
D
Costa
Antonino
A
Fisichella
Alfredo
A
Mazzone
Venera
V
Denaro
Luca
L
Avitabile
Marcello
M
Amenta
Francesco
F
Avola
Roberto
R
D000818:Animals; D001253:Astrocytes / Q000166:cytology*; D002454:Cell Differentiation / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D017077:Culture Media, Conditioned; D004815:Epidermal Growth Factor / Q000494:pharmacology; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D036341:Intercellular Signaling Peptides and Proteins / Q000494:pharmacology*; D051381:Rats
D017077:Culture Media, Conditioned; D007328:Insulin; D036341:Intercellular Signaling Peptides and Proteins; D016222:Fibroblast Growth Factor 2; D004815:Epidermal Growth Factor; D007334:Insulin-Like Growth Factor I