Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P42574 (caspase-3)
 45,978 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The bile salt, deoxycholate (DOC), can harm cells and cause disease. Hence, there is interest in identifying compounds capable of protecting cells against DOC. In HCT-116 colon epithelial cells, DOC increased generation of reactive oxygen species and caused DNA damage and apoptosis. These effects of DOC were inhibited by rottlerin, which is a phenolic compound of plant origin. In elucidating its mechansim, rottlerin prevented the release of cytochrome c from mitochondria into cytosol, and also prevented the cleavage of caspase-3. Yet, rottlerin by itself markedly decreased mitochondrial membrane potential and increased mitochondrial superoxide production, but this did not result in cytochrome c release or in caspase-3 cleavage. At a higher test concentration, two other phenolic phytochemicals, namely, quercetin and resveratrol, were each able to largely prevent the occurrence of apoptosis in cells exposed to DOC. In contrast, epigallocatechin gallate, curcumin, and genistein were ineffective.
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PMID:Protection of human colon epithelial cells against deoxycholate by rottlerin. 1866 Dec 40

Programmed cell death (PCD) is a key element in normal plant growth and development which may also be induced by various abiotic and biotic stress factors including salt stress. In the present study, morphological, biochemical, and physiological responses of the theoretically immortal unicellular freshwater green alga Micrasterias denticulata were examined after salt (200 mM NaCl or 200 mM KCl) and osmotic stress induced by iso-osmotic sorbitol. KCl caused morphological changes such as cytoplasmic vacuolization, extreme deformation of mitochondria, and ultrastructural changes of Golgi and ER. However, prolonged salt stress (24 h) led to the degradation of organelles by autophagy, a special form of PCD, both in NaCl- and KCl-treated cells. This was indicated by the enclosure of organelles by ER-derived double membranes. DNA of NaCl- and KCl-stressed cells but not of sorbitol-treated cells showed a ladder-like pattern on agarose gel, which means that the ionic rather than the osmotic component of salt stress leads to the activation of the responsible endonuclease. DNA laddering during salt stress could be abrogated by addition of Zn(2+). Neither cytochrome c release from mitochondria nor increase in caspase-3-like activity occurred after salt stress. Reactive oxygen species could be detected within 5 min after the onset of salt and osmotic stress. Respiration, photosynthetic activity, and pigment composition indicated an active metabolism which supports programmed rather than necrotic cell death in Micrasterias after salt stress.
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PMID:Salt stress-induced cell death in the unicellular green alga Micrasterias denticulata. 1926 93

Currently much attention has been given to the neurotoxicity of zinc, yet little is known about the influence of the counterions present. Therefore, we investigated the influence of different Zn(2+)-salts (concentrations range 0.05-0.3 mM) on cell viability, ATP and glutathione concentration and caspase activation in differentiated PC12 cells as a model for neuronal cells. Generally, at concentrations of 0.05 mM most Zn(2+)-salts were not cytotoxic except for zinc-citrate. At concentrations between 0.1 and 0.3 mM Zn(2+) a significant decrease in GSH and ATP levels preceded cell death induced by all salts, except of zinc-histidinate. Zinc-citrate and zinc-sulphate turned out to be the most toxic salts particularly at low concentrations. Analyses of caspase 3/7 activity showed that dependent on the concentration and the type of the salt used cell death may show more or less signs of both, necrosis and apoptosis. Interestingly, the uptake of Zn(2+) from zinc-sulphate and zinc-citrate was significantly higher than that of other salts, implicating a correlation between uptake and toxicity. In conclusion, Zn(2+)-salts could be divided into three categories with high (zinc-citrate, zinc-sulphate), moderate (zinc-orotate, zinc-acetate, zinc-chloride(,) zinc-gluconate) and low cytotoxicity (zinc-histidinate).
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PMID:Comparative in vitro toxicity of seven zinc-salts towards neuronal PC12 cells. 1930 23

Tetrazolium violet (TV), a tetrazolium salt, was synthesized as a novel and potent anticancer agent with a broad spectrum of anticancer activity against many cancer cells. A previous study showed that tetrazolium violet inhibited cell growth, and induced cell cycle arrest and apoptosis in C6 Rat glioma cells. It also showed that treatment of cells with TV for 24 h resulted in a dramatic up-regulation of p53, and an increase in the activity of caspase-3, accompanied with a significant increase of Bax/Bcl-2 ratio. In this study, we further investigated which Fas/FasL and caspase were activated by TV during the apoptosis. Annexin-V-propidium iodide (PI) binding assay and nucleosome ELISA assay further indicated that TV induced a typical apoptosis, in a time-dose-dependent manner. The data showed that the activity of Fas/FasL and caspase-8 and -9 were significantly enhanced by the compound, which suggested that TV might be used as a Fas/FasL and caspases promoter to initiate brain cancer cell apoptosis.
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PMID:Tetrazolium violet induces apoptosis via caspases-8, -9 activation and Fas/FasL up-regulation in rat C6 glioma cells. 1940 76

Plumbagin, a naphthoquinone derived from the medicinal plant Plumbago zeylanica has been shown to exert anticancer and anti-proliferative activities in cells in culture as well as animal tumor models. In our previous paper, we have reported the cytotoxic action of plumbagin in plasmid pBR322 DNA as well as human peripheral blood lymphocytes through a redox mechanism involving copper. Copper has been shown to be capable of mediating the action of several plant-derived compounds through production of reactive oxygen species (ROS). The objective of the present study was to determine whether plumbagin induces apoptosis in human cancer cells through the same mechanism which we proposed earlier. Using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt assay, 3-(4,5-B-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay for cell growth inhibition, histone/DNA ELISA, homogeneous caspase-3/7 assay for apoptosis as well as alkaline comet assay for DNA single-strand breaks detection in this report, we confirm that plumbagin causes effective cell growth inhibition, induces apoptosis and generates single-strand breaks in cancer cells. Incubation of cancer cells with scavengers of ROS and neocuproine inhibited the cytotoxic action of plumbagin proving that generation of ROS and Cu(I) are the critical mediators in plumbagin-induced cell growth inhibition. This study is the first to investigate the copper-mediated anticancer mechanism of plumbagin in human cancer cells and these properties of plumbagin could be further explored for the development of anticancer agents with higher therapeutic indices, especially for skin cancer.
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PMID:Plumbagin induces cell death through a copper-redox cycle mechanism in human cancer cells. 1950 95

Reactive oxygen species may cause oxidative damage in the placenta, yet some mechanisms must exist to reduce or prevent such damage. We investigated whether oxidative injury to placental endothelial cells is inhibited by activation of antioxidant enzymes by paracrine factors secreted by human placental multipotent mesenchymal stromal cells (hPMSC). hPMSC-conditioned medium and umbilical endothelial cells were assayed for cytokines and cytokine receptor expression by immunoassay and real-time PCR. Endothelial cell survival was evaluated by MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt] assay and caspase 3 activity assay. tert-Butyl hydroperoxide was used to induce oxidative injury in endothelial cells, with fluorescent microscopy and flow cytometry used to detect intracellular peroxides and cell apoptosis. Western blot, real-time PCR, STAT3 DNA-binding activity assay, and STAT3 siRNA were used to assess endothelial cell antioxidant enzymes. hPMSC-conditioned medium supported endothelial cell survival and reduced endothelial cell intracellular peroxides and apoptosis. hPMSCs expressed the transcripts of the interleukin (IL) 6 cytokine family, including IL6 and leukemia-inhibitory factor. hPMSC-conditioned medium activated STAT3 expression in endothelial cells, which was inhibited by neutralizing antibody to interleukin 6 signal transducer (IL6ST) but not to IL6 or leukemia-inhibitory factor. STAT3 siRNA or manganese superoxide dismutase (SOD2) siRNA transfected into endothelial cells inhibited the antiapoptotic effect of conditioned medium. SOD2 was significantly upregulated in endothelial cells by conditioned medium via STAT3 activation that, in turn, was inhibited by IL6ST-neutralizing antibody or STAT3 siRNA. Paracrine factors secreted by hPMSCs support endothelial cell survival. STAT3 activation and SOD2 production protect against oxidative stress-induced endothelial cell damage.
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PMID:Paracrine factors from human placental multipotent mesenchymal stromal cells protect endothelium from oxidative injury via STAT3 and manganese superoxide dismutase activation. 2010 4

Substituted quinolines (PQ code number), which reduce colony formation and increase gap junctional intercellular communication, were tested for their ability to interact with various molecular targets in murine and human tumor cell lines in vitro. Various markers of tumor cell metabolism, DNA fragmentation, mitotic disruption, apoptosis induction and growth factor receptor signaling pathways were assayed in vitro to evaluate drug cytotoxicity. Based on its ability to inhibit the metabolic activity of suspension cultures of leukemic L1210 cells at days 2 and 4 in vitro, PQ1 succinic acid salt is the most effective antiproliferative agent among the synthetic quinoline analogs tested. Moreover, antiproliferative PQ1 is effective across a spectrum of monolayer cultures of pancreatic Pan02, epidermoid A-431 and mammary SK-BR-3 and BT-474 tumor cells. PQ1 also blocks Ki-67 expression, a marker of tumor cell proliferation. A 1.5- to 3-h treatment with PQ1 is sufficient to inhibit the incorporations of [3H]-thymidine into DNA, [3H]-uridine into RNA and [3H]-leucine into protein used to assess the rates of macromolecule syntheses over a 0.5- or 1-h period of pulse-labeling in L1210 tumor cells. A 15-min pretreatment with PQ1 inhibits the cellular transport of both purine and pyrimidine nucleosides over a 30-sec period in vitro, suggesting that PQ1 may prevent the incorporation of [3H]-adenosine and [3H]-thymidine into DNA because it rapidly blocks the uptake of these nucleosides by the tumor cells. Since PQ1 does not reduce the fluorescence of the ethidium bromide-DNA complex, it does not directly bind to or destabilize double-stranded DNA. Over a 6- to -48-h period, PQ1 has very little effect on the mitotic index of L1210 cells but stimulates the formation of many binucleated cells and a few micronuclei, suggesting that this compound might increase mitotic abnormality, induce chromosomal damage or missegregation, and block cytokinesis. The fact that PQ1 induces initiator caspase-2 and effector caspase-3 activities and poly(ADP-ribose) polymerase-1 cleavage within 1-4 h and internucleosomal DNA fragmentation within 24 h in L1210 cells suggests that this antitumor drug can trigger the early and late events required for cells to undergo apotosis. Whole-cell immunodetection and Western blot analysis indicate that, in contrast to 17-(allylamino)-17-demethoxygeldanamycin and radicicol, PQ1 fails to down-regulate the protein level at 24 h and autophosphorylation at 3 h of membrane-anchored HER1 in A-431 cells and HER2 in SK-BR-3 cells, suggesting that this antitumor compound is unlikely to interact with and inhibit Hsp90 and the epidermal growth factor (EGF) receptor signaling pathways. In conclusion, antiproliferative PQ1 is effective against a spectrum of tumor cells and might interact with various membrane and nuclear targets to enhance gap junctions, inhibit nucleoside transport and block cytokinesis but does not appear to disrupt the EGF receptor-mediated signaling pathways to induce growth arrest and apoptosis.
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PMID:Bioactivity and molecular targets of novel substituted quinolines in murine and human tumor cell lines in vitro. 2012 88

Thellungiella halophila (T. halophila) suspension-cultured cells were used to gain knowledge of the pathway of programmed cell death (PCD) in halophytes under salt stress. Several apoptotic-like features occurred in T. halophila cells after exposure to 300 mM NaCl, including the retraction of the plasma membrane from the cell wall, nuclear condensation, DNA laddering and the release of cytochrome c accompanying the increase of caspase 3-like protease activity. This process resulted in ultrastructural changes of mitochondria and Golgi bodies, and autophagy was also induced by high salinity stress. DNA laddering and caspase 3-like activity were inhibited prior to the inhibition of cell death by a specific caspase 3 inhibitor, Ac-DEVD-CHO. The results indicate that 300 mM NaCl stress-induced PCD in T. halophila is similar to animal apoptosis, and this process occurs partly through a caspase 3-like dependent pathway.
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PMID:Salt stress induces programmed cell death in Thellungiella halophila suspension-cultured cells. 2041 88

Eukaryotic microalgae are highly suitable biological indicators of environmental changes because they are exposed to extreme seasonal fluctuations. The biochemical and molecular targets and regulators of key proteins involved in the stress response in microalgae have yet to be elucidated. This study presents morphological and biochemical evidence of programmed cell death (PCD) in a low temperature strain of Chlorella saccharophila induced by exposure to NaCl stress. Morphological characteristics of PCD, including cell shrinkage, detachment of the plasma membrane from the cell wall, nuclear condensation and DNA fragmentation, were observed. Additionally, a significant production of H(2)O(2) and increase in caspase 3-like activity were detected. We demonstrated that singly applied environmental stresses such as warming or salt stress trigger a pathway of PCD. Intriguingly, the prior application of salt stress seems to reduce heat shock-induced cell death significantly, suggesting a combined effect which activates a defense mechanism in algal cells. These results suggest that C. saccharophila can undergo PCD under stress conditions, and that this PCD shares several features with metazoan PCD. Moreover, the simultaneous exposure of this unicellular chlorophyte to different abiotic stresses results in a tolerance mechanism.
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PMID:Programmed cell death and adaptation: two different types of abiotic stress response in a unicellular chlorophyte. 2045 71

Caspase-12, mainly detected in endoplasmic reticulum (ER), has been suggested to play a role in ER-mediated apoptosis and inflammatory caspase activation pathway. Cleavage of the prodomain by caspase-3/-7 at the carboxyl terminus of Asp94 or m-calpain at the carboxyl terminus of Lys158 was reported to be a part of caspase-12-involved apoptosis. We biochemically characterized the prodomain-free forms of caspase-12 and the equivalent enzymes; Deltapro1(G95-D419), rev-Deltapro1[(T319-N419)-(G95-D318), a reverse form of Deltapro1] and rev-Deltapro2[(T319-N419)-(T159-D318)]. The three variants showed comparable activities which were dependent on salt concentration and pH. Auto-proteolytic cleavage was observed at two sites (carboxyl termini of Asp318 and Asp320) in Deltapro1. Constitutively active forms of caspase-12 (rev-Deltapro1 and rev-Deltapro2) could induce cell death in cells transfected with the corresponding expression vectors, but no cleavage of caspase-3, DFF45 or Bid was observed, indicating caspase-12 may mediate a distinct apoptotic pathway rather than caspase-8 or -9-mediated cell death.
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PMID:Purification of catalytically active caspase-12 and its biochemical characterization. 2064 90


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