Differential responsiveness of late passage C-6 glial cells and advanced passages of astrocytes derived from aged mouse cerebral hemispheres to cytokines and growth factors: glutamine synthetase activity.
In this study, we were interested to compare the responsiveness to growth factors, NGF, b-FGF and EGF and cytokines, IL1 beta, and TNF-alpha, in late passages (74-79) C6 glial cells committed astrocytes and astrocytes of advanced passages (26-28) in cultures derived from aged mouse cerebral hemispheres (MACH). Cultures were grown in either DMEM or chemically defined medium (CDM/TIPS) in order to test the effects of growth factors or cytokines. The activity of glutamine synthetase (GS), a marker for astrocytes, was used as a test parameter. We found that treatment with growth factors increased GS activity in both glial cell culture systems with the exception of EGF in C-6 glial cells. Treatment with cytokines markedly decreased GS activity in the late passage C6 glial cells whereas only TNF-alpha had a similar effect on MACH astrocytes. In view of the generally opposite effects of growth factors and cytokines on GS activity, we speculate that these molecules which are also endogenously present in glial cells may play a role in the maintenance of cellular homeostasis.
Kazazoglou
T
T
University Mental Health Research Institute, Eginition Hospital, Athens, Greece.
Fleischer-Lambropoulos
E
E
Geladopoulos
T
T
Kentroti
S
S
Stefanis
C
C
Vernadakis
A
A
D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D015415:Biomarkers; D001921:Brain / Q000166:cytology / Q000201:enzymology*; D002478:Cells, Cultured; D016922:Cellular Senescence; D003470:Culture Media; D016207:Cytokines / Q000494:pharmacology*; D004815:Epidermal Growth Factor / Q000494:pharmacology; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D005974:Glutamate-Ammonia Ligase / Q000032:analysis / Q000378:metabolism*; D006133:Growth Substances / Q000494:pharmacology*; D007375:Interleukin-1 / Q000494:pharmacology; D051379:Mice; D008809:Mice, Inbred C3H; D009414:Nerve Growth Factors / Q000494:pharmacology; D009457:Neuroglia / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D015415:Biomarkers; D003470:Culture Media; D016207:Cytokines; D006133:Growth Substances; D007375:Interleukin-1; D009414:Nerve Growth Factors; D014409:Tumor Necrosis Factor-alpha; D016222:Fibroblast Growth Factor 2; D004815:Epidermal Growth Factor; D005974:Glutamate-Ammonia Ligase