Nerve growth factor withdrawal-induced cell death in neuronal PC12 cells resembles that in sympathetic neurons.

Abstract

Abstract. 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 normeuronal (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.TAINMENT of proper cell number in each region of the organism is an essential aspect of development and morphogenesis. To accomplish this, not only is the rate of celt proliferation tightly regulated, but there is also a program of cell death which results in the elimination of specific subsets of cells (28,43,46). Programmed cell death (PCD) t provides a rapid and efficient method for achieving proper tissue mass and cell number as well as for eliminating supernumerary or dysfunctional cells. During neuronal development, PCD operates to ensure precise quantitative matching of presynaptic and postsynaptic pools of cells (28). Determination of neuronal survival appears to occur via an intercellular competition for a limited supply of target-derived neurotrophic support (28). Thus, an augmented supply of nerve growth factor (NGF) reduces ha vivo death of sympathetic and sensory neurons while NGF deprivation, in vivo or in vitro, causes them to die (21). PCI2 cells, grown in serum-containing medium, do not require NGF for their survival although treatment with NGF induces neuronal

E2F2 converts reversibly differentiated PC12 cells to an irreversible, neurotrophin-dependent state

“…A characteristic of PC12 cells is the reversibility of their di erentiation when treated with NGF in serum-containing medium. However, when induced to di erentiate by NGF in serum-free medium, PC12 cells exhibit dependence on NGF for their survival and undergo programmed cell death in its absence via mechanisms highly similar to terminally di erentiated sympathetic neurons (Mesner et al, 1992). As shown here, ectopic expression of E2F2 essentially converts di erentiated PC12 cells from a reversibly to a`terminally' di erentiated, NGFdependent state.…”

“…We have examined this question using the pheochromocytoma cell line, PC12, which exits the cell cycle and di erentiates into sympatheticlike neurons following treatment with NGF. These cells have proven highly useful in examining many important aspects of neuronal di erentiation, including cell cycle mechanisms that regulate growth arrest and its interactions with the neuronal di erentiation program (Buchkovich and Zi , 1994;Mesner et al, 1992;Yan and Zi , 1995). In particular, PC12 cells exhibit reversible arrest and di erentiation upon treatment with NGF in serum-containing medium (Greene and Tischler, 1976).…”

P53 mediates ceramide-induced apoptosis in SKN-SH cells

“…A typical feature of neuronal apoptosis is a requirement for new mRNA and protein synthesis (Johnson and Deckwerth, 1993). Mesner et al (1992) showed that actinomycin D and cycloheximide inhibit apoptosis in neuronal PC12 cells. We also ®nd that gene activation and protein synthesis soon after addition of ceramide is required for apoptosis of SKN-SH cells.…”

Nedd2 Is Required for Apoptosis after Trophic Factor Withdrawal, But Not Superoxide Dismutase (SOD1) Downregulation, in Sympathetic Neurons and PC12 Cells

“…In the rat pheochromocytoma PC12 line, a commonly used model for neuronal differentiation and cell death, apoptosis may be triggered by either trophic factor/nerve growth factor (NGF) withdrawal (Greene, 1978;Batistatou and Greene, 1991;Rukenstein et al, 1991;Mesner et al, 1992;Pittman et al, 1993;Lindenboim et al, 1995) or oxidative stress induced by downregulation of Cu 2ϩ /Zn 2ϩ superoxide dismutase (SOD1) (Troy and Shelanski, 1994;Troy et al, 1996a-c). The initiating mechanisms of death seem to be distinct in each instance.…”