Nerve growth factor and epidermal growth factor rescue PC12 cells from programmed cell death induced by etoposide: Distinct modes of protection against cell death by growth factors and a protein-synthesis inhibitor

1994 ◽  
Vol 176 (2) ◽  
pp. 161-164 ◽  
Author(s):  
Mitsunari Nakajima ◽  
Kumiko Kashiwagi ◽  
Jun Ohta ◽  
Shoei Furukawa ◽  
Kyozo Hayashi ◽  
...  
1992 ◽  
Vol 119 (6) ◽  
pp. 1669-1680 ◽  
Author(s):  
P W Mesner ◽  
T R Winters ◽  
S H Green

Previous studies have shown that in neuronal cells the developmental phenomenon of programmed cell death is an active process, requiring synthesis of both RNA and protein. This presumably reflects a requirement for novel gene products to effect cell death. It is shown here that the death of nerve growth factor-deprived neuronal PC12 cells occurs at the same rate as that of rat sympathetic neurons and, like rat sympathetic neurons, involves new transcription and translation. In nerve growth factor-deprived neuronal PC12 cells, a decline in metabolic activity, assessed by uptake of [3H]2-deoxyglucose, precedes the decline in cell number, assessed by counts of trypan blue-excluding cells. Both declines are prevented by actinomycin D and anisomycin. In contrast, the death of nonneuronal (chromaffin-like) PC12 cells is not inhibited by transcription or translation inhibitors and thus does not require new protein synthesis. DNA fragmentation by internucleosomal cleavage does not appear to be a consistent or significant aspect of cell death in sympathetic neurons, neuronal PC12 cells, or nonneuronal PC12 cells, notwithstanding that the putative nuclease inhibitor aurintricarboxylic acid protects sympathetic neurons, as well as neuronal and nonneuronal PC12 cells, from death induced by trophic factor removal. Both phenotypic classes of PC12 cells respond to aurintricarboxylic acid with similar dose-response characteristics. Our results indicate that programmed cell death in neuronal PC12 cells, but not in nonneuronal PC12 cells, resembles programmed cell death in sympathetic neurons in significant mechanistic aspects: time course, role of new protein synthesis, and lack of a significant degree of DNA fragmentation.


1987 ◽  
Vol 114 (2) ◽  
pp. 179-184 ◽  
Author(s):  
S. Atkinson ◽  
P. Kendall-Taylor

ABSTRACT Primary cultures of porcine thyroid cells, grown as monolayers, showed saturable binding of epidermal growth factor (EGF). Scatchard analysis resolved the binding to a high-affinity/low-capacity site (dissociation constant = 0·17 nmol/l, maximal binding capacity = 1·67 pmol/106 cells) and a low-affinity/high-capacity site. Preincubation of thyroid monolayers with TSH for 3 days caused an increase in binding of 125I-labelled EGF due to an increase in the number of receptors, with the binding affinity unchanged. This effect was dose-dependent within the range of TSH concentrations 0·01–100 mu/l. The same effect was seen with dibutyryl cyclic AMP (10–1000 μmol/l). When the protein synthesis inhibitor cycloheximide was included in the TSH preincubation, the increase in EGF binding was abolished. The TSH effect on EGF binding was not mediated by thyroid hormones, since neither thyroxine (T4) nor tri-iodothyronine (T3) at 01 nmol/l–10 μmol/l could mimic the effect of TSH, nor could antisera to T3 or T4 neutralize the effect of TSH. The concentration of extracellular iodide (10 nmol/l–10 mmol/l) had no effect on the binding of 125I-labelled EGF. The results demonstrate that TSH increases the number of receptor sites for binding of EGF to thyroid monolayers in vitro. This effect is dependent upon protein synthesis and is mediated by cyclic AMP but not by thyroid hormones or iodide. This effect on binding of EGF may contribute to the trophic action of TSH. J. Endocr. (1987) 114, 179–184


Development ◽  
1980 ◽  
Vol 58 (1) ◽  
pp. 93-106
Author(s):  
Mary S. Tyler ◽  
Robert M. Pratt

Previous studies have shown that epidermal growth factor (EGF), a peptide of m.w. 6045, can specifically inhibit in organ culture the cessation of DNA synthesis and programmed cell death that normally occur in the presumptive fusion zone (PFZ) of the secondary palatal epithelium. The aim of this study was to determine if EGF acts directly on the epithelium to exert its effect and if there is a requirement for the underlying mesenchyme. Palatal processes from 13- and 14-day Swiss Webster embryonic mice were enzymatically separated into epithelium and mesenchyme which were then cultured alone or in transfilter recombination for up to 72 h. Tissues were examined by transmission- and scanning-electron microscopy and DNA synthesis was monitored autoradiographically using [3H]thymidine incorporation. In isolated epithelium cultured in control medium, cell death occurred in the PFZ and DNA synthesis did not occur in the oral and nasal epithelial regions. EGF (20–50 ng/ml) did not prevent cell death in the PFZ and failed to stimulate DNA synthesis in the isolated epithelium; EGF, however, did have an effect on epithelial cell morphology. In the presence of mesenchyme and EGF, there was extensive proliferation in the entire epithelium and cell death within the PFZ was not evident. The results indicate that the stimulation of DNA synthesis in the palatal epithelium by EGF requires the presence of the underlying mesenchyme and that EFG alone is not sufficient to inhibit programmed cell death within the PFZ of the isolated palatal epithelium.


1988 ◽  
Vol 59 (02) ◽  
pp. 248-250 ◽  
Author(s):  
Ari Ristimäki ◽  
Olavi Ylikorkala ◽  
Jaakko Perheentupa ◽  
Lasse Viinikka

SummaryEpidermal growth factor (EGF) stimulated prostacyclin (PGI2) production by cultured human umbilical vein endothelial cells, as measured by radioimmunoassay of its stable metabolite 6-keto- prostaglandin Flα. This effect of EGF was dose-dependent, the lowest stimulatory concentration of EGF was 1.0 ng/ml and 100 ng/ml caused a 2.7 ± 0.3 (mean ± SEM) fold increase in the PGI2 synthesis. The stimulation appeared at 3-6 h of incubation and lasted at least 24 h. It was suppressed by EGF antibodies and blocked by protein synthesis inhibitor cycloheximide. Cells preincubated 12 h with EGF released also higher amounts of PGI2when incubated with thrombin for 5 min. It is concluded that EGF liberated from platelets during aggregation may prevent local thrombogenesis and atherogenesis by stimulating the release of the antiaggregatory, vasodilatory PGI2 from vascular endothelial cells.


1993 ◽  
Vol 123 (5) ◽  
pp. 1207-1222 ◽  
Author(s):  
T L Deckwerth ◽  
E M Johnson

The time course of molecular events that accompany degeneration and death after nerve growth factor (NGF) deprivation and neuroprotection by NGF and other agents was examined in cultures of NGF-dependent neonatal rat sympathetic neurons and compared to death by apoptosis. Within 12 h after onset of NGF deprivation, glucose uptake, protein synthesis, and RNA synthesis fell precipitously followed by a moderate decrease of mitochondrial function. The molecular mechanisms underlying the NGF deprivation-induced decrease of protein synthesis and neuronal death were compared and found to be different, demonstrating that this decrease of protein synthesis is insufficient to cause death subsequently. After these early changes and during the onset of neuronal atrophy, inhibition of protein synthesis ceased to halt neuronal degeneration while readdition of NGF or a cAMP analogue remained neuroprotective for 6 h. This suggests a model in which a putative killer protein reaches lethal levels several hours before the neurons cease to respond to readdition of NGF with survival and become committed to die. Preceding loss of viability by 5 h and concurrent with commitment to die, the neuronal DNA fragmented into oligonucleosomes. The temporal and pharmacological characteristics of DNA fragmentation is consistent with DNA fragmentation being part of the mechanism that commits the neuron to die. The antimitotic and neurotoxin cytosine arabinoside induced DNA fragmentation in the presence of NGF, supporting previous evidence that it mimicked NGF deprivation-induced death closely. Thus trophic factor deprivation-induced death occurs by apoptosis and is an example of programmed cell death.


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