scholarly journals Internucleosomal DNA cleavage and neuronal cell survival/death

1993 ◽  
Vol 122 (3) ◽  
pp. 523-532 ◽  
Author(s):  
A Batistatou ◽  
LA Greene

Serum-free PC12 cell cultures have been used to study the mechanisms of neuronal death after neurotrophic factor deprivation. We previously reported that PC12 cells undergo "apoptotic" internucleosomal DNA cleavage after withdrawal of trophic support. Here, we have used a sensitive method to detect PC12 cell DNA fragmentation within three hrs of serum removal and have exploited this assay to examine several aspects regarding the mechanisms of neuronal survival/death. Major advantages of this assay are that it permits acute experiments to be performed well before other manifest signs of cell death and under conditions that cannot be applied chronically. We find that this apopotic DNA fragmentation is distinct from the random DNA degradation that occurs during necrotic death. Major observations include the following: (a) There is a good correlation between the ability of trophic substances to promote PC12 cell survival and to inhibit early DNA fragmentation. (b) Phorbol ester, an activator of PKC, acutely suppresses DNA fragmentation, but does not promote long-term survival or inhibition of endonuclease activity when applied chronically due to its downregulation of PKC. (c) Cells undergoing apoptosis within 3 h of serum withdrawal have a "commitment point" of only 1.0-1.5 h beyond which they can no longer be rescued by NGF. (d) Aurin, a non-carboxylic analog of the endonuclease inhibitor ATA, also inhibits DNA fragmentation and promotes short-term survival of PC12 cells. (e) Macromolecular synthesis is not required for DNA fragmentation or for NGF to prevent this event. (f) Extracellular Ca2+ is not required for internucleosomal DNA cleavage caused by serum withdrawal or for suppression of this by NGF. (g) DNA fragmentation can also be detected in cultures of rat sympathetic neurons as early as 10 h after removal of NGF. As in PC12 cell cultures, this precedes morphological signs of cell death.

1991 ◽  
Vol 115 (2) ◽  
pp. 461-471 ◽  
Author(s):  
A Batistatou ◽  
L A Greene

Past studies have shown that serum-free cultures of PC12 cells are a useful model system for studying the neuronal cell death which occurs after neurotrophic factor deprivation. In this experimental paradigm, nerve growth factor (NGF) rescues the cells from death. It is reported here that serum-deprived PC12 cells manifest an endonuclease activity that leads to internucleosomal cleavage of their cellular DNA. This activity is detected within 3 h of serum withdrawal and several hours before any morphological sign of cell degeneration or death. NGF and serum, which promote survival of the cells, inhibit the DNA fragmentation. Aurintricarboxylic acid (ATA), a general inhibitor of nucleases in vitro, suppresses the endonuclease activity and promotes long-term survival of PC12 cells in serum-free cultures. This effect appears to be independent of macromolecular synthesis. In addition, ATA promotes long-term survival of cultured sympathetic neurons after NGF withdrawal. ATA neither promotes nor maintains neurite outgrowth. It is hypothesized that the activation of an endogenous endonuclease could be responsible for neuronal cell death after neurotrophic factor deprivation and that growth factors could promote survival by leading to inhibition of constitutively present endonucleases.


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.


2019 ◽  
Vol 109 (2) ◽  
pp. 152-164 ◽  
Author(s):  
Zesergio Melo ◽  
Ximena Castillo ◽  
Bibiana Moreno-Carranza ◽  
María G. Ledesma-Colunga ◽  
Edith Arnold ◽  
...  

Background: Vasoinhibin, a protein derived from prolactin, regulates various vascular functions including endothelial cell survival. Of note, vasoinhibin is present in the central nervous system, where it triggers neuroendocrine and behavioral responses to stress. Moreover, vasoinhibin compromises nerve growth factor (NGF)-induced neurite outgrowth in primary sensory neurons of the peripheral nervous system. Nonetheless, information on the functions of vasoinhibin in developing neurons remains limited. The present study explored whether vasoinhibin affects the neurotrophic actions of NGF by measuring the cell differentiation and survival of PC12 pheochromocytoma cells. Methods: The effects of recombinant or lentiviral vector-transduced human vasoinhibin were tested on differentiating PC12 cells. Neurite outgrowth was quantified by measuring their length and density. The MTT assay was employed to assess cell viability, and ELISA was used to quantify DNA fragmentation as an index of apoptosis. Phosphorylated Akt and ERK1/2 were analyzed by Western blotting. Results: The addition of a human recombinant vasoinhibin, and the transduction of a lentiviral vector carrying a human vasoinhibin sequence, significantly reduced NGF-induced neurite outgrowth, cell survival, and phosphorylation of Akt and ERK1/2, and increased DNA fragmentation and caspase 3 activation in PC12 cells. Conclusions: Vasoinhibin downregulates NGF-induced differentiation and survival of PC12 cells, blocking tropomyosin receptor kinase A-triggered signaling pathways and increasing apoptosis. These results establish that vasoinhibin interaction with NGF and other neurotrophins may be critical in mediating pathways involved in neuronal survival and differentiation.


1997 ◽  
Vol 121 (1) ◽  
pp. 122-127 ◽  
Author(s):  
T. Aoki ◽  
T. Koike ◽  
T. Nakano ◽  
K. Shibahara ◽  
S. Kondo ◽  
...  

2003 ◽  
Vol 375 (1) ◽  
pp. 99-109 ◽  
Author(s):  
Claire J. CHALMERS ◽  
Kathryn BALMANNO ◽  
Kathryn HADFIELD ◽  
Rebecca LEY ◽  
Simon J. COOK

To investigate the role of thrombin in regulating apoptosis, we have used CCl39 cells, a fibroblast cell line in which thrombin-induced cell proliferation has been extensively studied. Withdrawal of serum from CCl39 cells resulted in a rapid apoptotic response that was completely prevented by the inclusion of thrombin. The protective effect of thrombin was reversed by pertussis toxin, suggesting that cell-survival signalling pathways are activated via a Gi or Go heterotrimeric GTPase. Serum-withdrawal-induced death required de novo gene expression and was preceded by the rapid de novo expression of the pro-apoptotic ‘BH3-only’ protein Bim (Bcl-2-interacting mediator of cell death). Thrombin strongly inhibited the up-regulation of both Bim protein and Bim mRNA. The ability of thrombin to repress Bim expression, and to protect cells from apoptosis, was reversed by U0126, a MEK1/2 [MAPK (mitogen-activated protein kinase) or ERK (extracellular-signal-regulated kinase) 1/2] inhibitor, or LY294002, a phosphoinositide 3′-kinase (PI3K) inhibitor, suggesting that both the Raf→MEK→ERK1/2 and PI3K pathways co-operate to repress Bim and promote cell survival. A PAR1p (protease-activated receptor 1 agonist peptide) was also able to protect cells from serum-withdrawal-induced apoptosis, suggesting that thrombin acts via PAR1 to prevent apoptosis.


2001 ◽  
Vol 76 (6) ◽  
pp. 1745-1755 ◽  
Author(s):  
Dongmei Jiang ◽  
Nandita Jha ◽  
Rapee Boonplueang ◽  
Julie K. Andersen

2002 ◽  
Vol 97 (1) ◽  
pp. 24-32 ◽  
Author(s):  
Manuela J. M. de Klaver ◽  
Lee Manning ◽  
Lisa A. Palmer ◽  
George F. Rich

Background Anesthetics are protective during ischemic-reperfusion injury and associated inflammation; therefore, the authors hypothesized that anesthetic pretreatment may provide protection in culture from cytokine-induced cell death. Methods Rat vascular smooth muscle (VSM) cell and human umbilical vascular endothelial cell (HUVEC) cultures were used to determine whether pretreatment with 30 min of isoflurane decreases cell death from tumor necrosis factor alpha (TNF-alpha), interleukin 1 (IL-1 beta), and interferon (IFN-gamma) alone or in combination. Cell survival and viability were determined by trypan blue staining and cell proliferation assay, as well as by DNA fragmentation assays. The roles of protein kinase C (PKC) and adenosine triphosphate-sensitive potassium (K(ATP)) channels in mediating isoflurane (and halothane) protection were evaluated with the antagonists staurosporine or glibenclamide in cytokine- and also hydrogen peroxide (H(2)O(2))-induced cell death. Results Pretreatment with 1.5% isoflurane immediately prior to cytokine exposure increased cell survival and viability from cytokines by 10-60% for 24, 48, 72, and 96 h in VSMs and up to 72 h in HUVECs. DNA fragmentation (TUNEL) was also attenuated by isoflurane. Isoflurane was equally effective in VSMs at 0.75, 1.5, and 2.5%, whereas in HUVECs, 1.5 and 2.5% were more effective than 0.75%. In VSMs, isoflurane administered 1 h prior to or simultaneously with cytokines was also effective, whereas isoflurane 2 h prior to cytokines was less effective, and either 4 h prior to or 30 min after cytokines was not effective. In both cytokine- and H(2)O(2)-induced cell death, isoflurane and halothane pretreatment were equally protective, and staurosporine and glibenclamide attenuated the protective effect. Conclusions Thirty minutes of isoflurane attenuates cytokine-induced cell death and increases cell viability in VSMs for 96 h and in HUVECs for 72 h. Isoflurane must be administered less than 2 h prior to or simultaneously with the cytokines to be protective. These initial inhibitor studies suggest involvement of PKC and K(ATP) channels in isoflurane and halothane protection against both cytokine- and H(2)O(2)-induced cell death of VSMs and HUVECs.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11401
Author(s):  
Cuiyan Zhou ◽  
Weihai Ying

Background. Multiple studies have indicated crucial roles of NAD+ deficiency in several neurological diseases and aging. It is critical to discover the mechanisms underlying the NAD+ deficiency. A decreased level of Nicotinamide phosphoribosyltransferase (Nampt)—an important enzyme in the salvage pathway of NAD+ synthesis—has been found under certain pathological conditions, while the mechanisms underlying the Nampt decrease are unclear. The purpose of this study is to test the hypothesis that oxidative stress can produce decreased Nampt, and to investigate the biological effects of Nampt on NAD+ synthesis and cell survival under both basal and oxidative stress conditions. Methods. We used differentiated PC12 cells as a cellular model to investigate the effects of oxidative stress on the levels of Nampt. Multiple assays, including flow cytometry-based cell death assays and NAD+ assays were conducted. Results. First, oxidative stress can decrease the levels of Nampt mRNA and Nampt protein; second, Nampt plays significant roles in NAD+ synthesis under both basal conditions and oxidative stress conditions; third, Nampt plays critical roles in cell survival under both basal conditions and oxidative stress conditions; and fourth, oxidative stress produced decreased NAD+ levels and cell survival partially by decreasing Nampt. Collectively, our study has indicated that oxidative stress is a pathological factor leading to decreased Nampt, which plays important roles in oxidative stress-produced decreases in NAD+ levels and cell survival. Our findings have indicated major roles of Nampt in maintaining NAD+ levels and cell survival under both basal and oxidative stress conditions.


2007 ◽  
Vol 30 (4) ◽  
pp. 682-686 ◽  
Author(s):  
Masumi Sasaki ◽  
Hiroyuki Nakamura ◽  
Shizuko Tsuchiya ◽  
Syunji Horie ◽  
Makoto Kashiwayanagi ◽  
...  

2002 ◽  
Vol 96 (5) ◽  
pp. 1191-1201 ◽  
Author(s):  
Zhiming Tan ◽  
Shuji Dohi ◽  
Jinen Chen ◽  
Yosiko Banno ◽  
Yoshinori Nozawa

Background To explore whether cytotoxicity of local anesthetics is related to apoptosis, the authors examined how local anesthetics affect mitogen-activated protein kinase (MAPK) family members, extracellular signal-regulated kinases (ERKs), c-Jun N-terminal kinases (JNKs)-stress-activated protein kinases, and p38 kinase, which are known to play important roles in apoptosis. Methods Cell death was evaluated using PC12 cells. Morphologic changes of cells, cellular membrane, and nuclei were observed. DNA fragmentation was electrophoretically assayed. Western blot analysis was performed to analyze phosphorylation of the MAPK family, cleavage of caspase-3 and poly(adenosine diphosphate-ribose) polymerase. Intracellular Ca2+ concentration was measured using a calcium indicator dye. Results Tetracaine-induced cell death was shown in a time- and concentration-dependent manner and characterized by nuclear condensation or fragmentation, membrane blebbing, and internucleosomal DNA fragmentation. Caspase-3 activation and phosphorylation of ERK, JNK, and p38 occurred in the cell death. PD98059, an inhibitor of ERK, enhanced tetracaine-induced cell death and JNK phosphorylation, whereas ERK phosphorylation was inhibited. Curcumin, an inhibitor of JNK pathway, attenuated the cell death. Increase of intracellular Ca2+ concentration was detected. In addition to the increase of ERK phosphorylation and the decrease of JNK phosphorylation, two Ca2+ chelators protected cells from death. Neither cell death nor phosphorylation of the MAPK family was caused by tetrodotoxin. Nifedipine did not affect tetracaine-induced apoptosis. Conclusions Tetracaine induces apoptosis of PC12 cells via the MAPK family. ERK activation protects cells from death, but JNK plays the opposite role. Toxic Ca2+ influx caused by tetracaine seems to be responsible for the cell death, but blocking of Na+ channels or L-type Ca2+ channels is unlikely involved in the tetracaine's action for apoptosis.


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