Recombinant human ciliary neurotrophic factor stimulates the metabolic activity of SH-SY5Y cells as measured by a cytosensor microphysiometer.
Information on the transmembrane signaling events and subsequent biochemical processes initiated by ciliary neurotrophic factor (CNTF) receptor activation in neurons is lacking. SH-SY5Y cells, a human neuroblastoma cell line expressing CNTF receptors, were used to study metabolic changes associated with functional ligand-receptor interactions. Real-time measurements quantifying the rate of extracellular acidification by SH-SY5Y cells (a measure of metabolic activity) were made using a silicon-based cytosensor. Application of recombinant human CNTF (rhCNTF) to resting SH-SY5Y cells increased their acidification rate in a concentration and time-dependent manner with an apparent EC50 of 60 ng/ml. Pretreatment of cells with phosphatidylinositol-specific phospholipase C (PI-PLC) prevented the CNTF, but not an NGF-stimulated increase in acidification rate. Collectively, these results demonstrate that: (1) SH-SY5Y cells express functional CNTF receptors; and (2) the initial signal transduction mechanism activated by the CNTF receptor in SH-SY5Y cells is distinct from that activated by the NGF receptor; however, both may ultimately stimulate the same downstream biochemical messengers to increase cellular metabolism.
Johnson
R M
RM
Department of Neurosciences, Syntex Discovery Research, Palo Alto, CA 94304.
McNeeley
P A
PA
DeMoor
K
K
Stewart
G R
GR
Glaeser
B S
BS
Pitchford
S
S
D000818:Animals; D002460:Cell Line; D020934:Ciliary Neurotrophic Factor; D004305:Dose-Response Relationship, Drug; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D051379:Mice; D009414:Nerve Growth Factors / Q000494:pharmacology; D009419:Nerve Tissue Proteins / Q000378:metabolism / Q000494:pharmacology*; D009447:Neuroblastoma; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D054801:Phosphoinositide Phospholipase C; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D020801:Receptor, Ciliary Neurotrophic Factor; D017978:Receptors, Growth Factor / Q000096:biosynthesis*; D017475:Receptors, Nerve Growth Factor / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000378:metabolism / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D020934:Ciliary Neurotrophic Factor; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; D020801:Receptor, Ciliary Neurotrophic Factor; D017978:Receptors, Growth Factor; D017475:Receptors, Nerve Growth Factor; D011994:Recombinant Proteins; D010727:Phosphoric Diester Hydrolases; D054801:Phosphoinositide Phospholipase C; D043265:Phosphatidylinositol Diacylglycerol-Lyase