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 maturation of epiphyseal chondrocytes is accompanied by dramatic changes in energy metabolism and shifts in proteins concerned with the induction of apoptosis. We evaluated the role of mitochondria in this process by evaluating the membrane potential (Delta psi m) of chondrocytes of embryonic tibia and the epiphyseal growth plate. We observed that there was a maturation-dependent change in fluorescence, indicating a fall in the Delta psi m. The level of mitochondrial Bcl-2 was decreased during maturation, while in the same time period there was an obvious increase in Bax levels in the mitochondrial fraction of the terminally differentiated chondrocytes. Bcl(xL), another anti-apoptotic protein, was also robustly expressed in the mitochondrial fraction, but its expression was not dependent on the maturation status of the chondrocytes. We found that caspase-3 was present throughout the growth plate and in hypertrophic cells in culture. We blocked caspase-3 activity and found that alkaline phosphatase staining and mineral formation was decreased, and the cells had lost their characteristic shape. Moreover, we noted that the undifferentiated cells were insensitive to elevated concentrations of inorganic phosphate (Pi). It is concluded that during hypertrophy, the change in membrane potential, the increased binding of a pro-apoptotic protein to mitochondria, and the activation of caspase-3 serve to prime cells for apoptosis. Only when the terminally differentiated chondrocytes are challenged with low levels of apoptogens there is activation of apoptosis.
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PMID:Development of the terminally differentiated state sensitizes epiphyseal chondrocytes to apoptosis through caspase-3 activation. 1713 57

We studied the hepatocellular alterations induced by sub-lethal concentrations (0.50 muM) of arsenic in Indian catfish Clarias batrachus L. Sub-lethal arsenic exposure altered serum aspartate aminotransferase and alkaline phosphatase levels and brought about significant changes in different serum biochemical parameters. Arsenic exposure reduced total hepatocyte protein content and suppressed the proliferation of hepatocytes in a time-dependent manner. Routine histological studies on liver documented arsenic-induced changes characterized by dilated sinusoids, formation of intracellular edema, megalocytosis, vacuolation and appearance of hepatic cells with distorted nuclei. Transmission electron microscopy of hepatocytes further revealed hyperplasia and hypertrophy of mitochondria, development of dilated rough endoplasmic reticulum and changes in peroxisome size with duration of arsenic exposure. Degeneration of mitochondrial cristae and condensation of chromatin was also evident in arsenic-exposed hepatocytes. A significant number of hepatocytes isolated from arsenic-exposed fish stained with annexin V and demonstrated DNA ladder characteristic of apoptosis. Single-cell gel electrophoresis of exposed hepatocytes also revealed the development of comets usually seen in apoptotic cells. Using specific inhibitors it was determined that the arsenic-induced apoptosis of hepatocytes was caspase-mediated, involving the caspase 3 pathway.
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PMID:Sub-lethal concentration of arsenic interferes with the proliferation of hepatocytes and induces in vivo apoptosis in Clarias batrachus L. 1733 63

Food containing soybeans provide isoflavone phytoestrogens that can preserve bone mass in postmenopausal women, and prevent bone loss in ovariectomized rats. But their effects on bone remain unclear, particularly on bone formation during growth. Two groups of eight pre-pubertal piglets were fed a basal or an isoflavone-enriched (S800) diet for 6 weeks. The S800 diet contained 800 mg SoyLifetrade mark/kg, providing 2.8 mg isoflavones/kg body weight/day. Several bones were collected and tested for bone strength and density. Bone marrow was collected from humeri together with blood samples and genital tracts. The plasma concentrations of isoflavones were increased in the pigs fed S800, but growth rate, body weight, plasma bone markers, bone mineral density, and strength were all unaffected. In contrast, cultured stromal cells from S800 pigs had more alkaline phosphatase-rich cells and mineralized nodules, secreted more osteocalcin, osteoprotegerin and RANK-L, synthesized more osteoprotegerin, and RANK-L. Cultured mononucleated nonadherent bone marrow cells from S800 pigs developed fewer tartrate-resistant acid phosphatase mononucleated cells (osteoclast progenitors) when cultured with 1,25(OH)(2)D(3), and resorbed a smaller area of dentine slices. Freshly isolated bone marrow osteoclast progenitors from S800 pigs had more caspase-3 cleavage activity, and synthesized less RANK. Both osteoclast and osteoblast progenitors had ERalpha and ERbeta, whose syntheses were stimulated by the S800 diet. The S800 piglets had heavier ovaries with more follicles, but their uterus weight was unaffected. We conclude that dietary isoflavones have no detectable effect on the bone mass of growing female piglets, but act on bone marrow osteoprogenitors via ERs--mainly ERbeta, and stimulate ovary development.
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PMID:Dietary isoflavones act on bone marrow osteoprogenitor cells and stimulate ovary development before influencing bone mass in pre-pubertal piglets. 1734 29

TP508 is a 23-amino acid peptide derived from human prothrombin that increases cartilage matrix production and reduces alkaline phosphatase activity without changing chondrocyte proliferation. This study tested the hypothesis that TP508 acts by blocking the onset of apoptosis associated with hypertrophy. Rat costochondral resting zone chondrocytes and human auricular chondrocytes were cultured in DMEM containing 50microM ascorbic acid and 10% FBS. Apoptosis was induced by treatment of confluent cultures with chelerythrine, tamoxifen, or inorganic phosphate (Pi) for 24h. One half of the cultures received TP508 (0, 0.7, or 7microg/ml). Apoptosis was assessed as a function of DNA fragmentation ([3H]-thymidine labeled DNA fragments), TUNEL staining, and cell viability using the MTT assay, as well as by assessing the Bcl-2/Bax mRNA and protein ratios and caspase-3 activity. The universal NO synthase inhibitor l-NMMA was used to assess the effect of NO production on chondrocyte apoptosis and specific NO synthase subspecies were identified using iNOS inhibitor 1400W and nNOS inhibitor vinyl-l-NIO, as well as l-NAME, which inhibits both iNOS and eNOS. Finally, we assessed if TP508 would block NO production induced by the apoptogens. Chelerythrine, tamoxifen and Pi-induced apoptosis and this was reversed by TP508. All apoptogens increased NO production and this was reduced by TP508. TP508 reduced NO levels to the same extent as 1400W but not to the same extent as l-NAME, suggesting that its effects are mediated primarily by iNOS. In addition, TP508 reduced the effect of chelerythrine to the same extent as 1400W and l-NAME, again indicating that it acts via inhibition of an iNOS pathway. TP508 also regulated Bcl-2/Bax mRNA in a time and dose-dependent manner. The Bcl-2/Bax mRNA ratio was 0.11 in the absence of TP508 at 1h and 4.95 at 7microg/ml TP508; by 3h the ratio was approximately 1 in both groups. The Bcl-2/Bax protein ratio also increased by 63% at 1h. TP508 did not affect caspase-3 activity. TP508 also caused a dose-dependent increase in protein kinase C (PKC) activity within 9min that was maximal at 270min. These results show that TP508 prevents apoptosis in growth plate chondrocytes via inhibition of iNOS-dependent NO and suggest a possible role for PKC in the mechanism.
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PMID:Thrombin peptide TP508 prevents nitric oxide mediated apoptosis in chondrocytes in the endochondral developmental pathway. 1802 91

Chemoprevention is regarded as one of the most promising and realistic approaches in the prevention of human cancer. Diallyl sulfide (DAS), an organosulfur component of garlic has been known for its chemopreventive activities against various cancers and also in recent years, numerous investigations have shown that sulfur-containing compounds induce apoptosis in multiple cell lines and experimental animals. Thus the present study was focused to elucidate the anticancerous effect and the mode of action of DAS against Colo 320 DM colon cancer cells. DAS induced apoptosis in Colo 320 DM cells was revealed by flow cytometer analysis and phosphatidyl serine exposure. DAS also promoted cell cycle arrest substantially at G2/M phase in Colo 320 DM cells. The production of reactive oxygen intermediates, which were examined by 2,7-dichlorodihydrofluorescein diacetate (H2DCF-DA), increased with time, after treatment with DAS. The activities of alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) were decreased upon DAS treatment, which shows the antiproliferative and the cytotoxic effects, respectively. The expression of NF-kappaB was upregulated in DAS treated cells, compared to normal cells. Further, DAS promoted the expression of caspase-3 and suppression of Extracellular Regulatory Kinase-2 (ERK-2) activity in Colo 320 DM cells that was determined by Western blot analysis. In conclusion, DAS increased the production of ROS, caused cell cycle arrest, decreased cell proliferation and induced apoptosis in Colo 320 DM cells. Thus, this study put forward DAS as a drug that can possibly be used to treat cancers.
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PMID:Diallyl sulfide induces apoptosis in Colo 320 DM human colon cancer cells: involvement of caspase-3, NF-kappaB, and ERK-2. 1825 91

Advanced glycation endproducts (AGEs) are implicated in the complications of diabetes and ageing, affecting several tissues, including bone. Metformin, an insulin-sensitizer drug, reduces the risk of life-threatening macrovascular complications. We have evaluated the hypothesis that metformin can abrogate AGE-induced deleterious effects in osteoblastic cells in culture. In two osteoblast-like cell lines (UMR106 and MC3T3E1), AGE-modified albumin induced cell death, caspase-3 activity, altered intracellular oxidative stress and inhibited alkaline phosphatase activity. Metformin-treatment of osteoblastic cells prevented these AGE-induced alterations. We also assessed the expression of AGE receptors as a possible mechanism by which metformin could modulate the action of AGEs. AGEs-treatment of osteoblast-like cells enhanced RAGE protein expression, and this up-regulation was prevented in the presence of metformin. Although the precise mechanisms involved in metformin signaling are still elusive, our data implicate the AGE-RAGE interaction in the modulation of growth and differentiation of osteoblastic cells.
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PMID:Metformin reverts deleterious effects of advanced glycation end-products (AGEs) on osteoblastic cells. 1827 53

This study was designed to investigate the protective effects of the phenethyl ester of caffeic acid (CAPE) against carbon tetrachoride (CCl(4))-induced hepatotoxicities in mice. Pretreatment with CAPE prior to administration of CCl(4) significantly prevented the increases in serum alanine, aspartate aminotransferase and alkaline phosphatase activities, hepatic lipid peroxidation formation, and depletion of glutathione content. In addition, CAPE prevented CCl(4)-induced apoptosis and necrosis, as indicated by liver histopathology and DNA laddering studies. To determine whether the Fas/Fas ligand (FasL) pathway is involved in CCl(4)-induced acute liver injury, Fas and FasL proteins and caspase-3 and -8 activities were tested by western blotting and ELISA. CAPE markedly decreased CCl(4)-induced Fas/FasL protein expression levels and, in turn, attenuated CCl(4)-induced caspase-3 and -8 activities in mouse liver. Moreover, the effect of CAPE on CYP2E1, the major isozyme involved in CCl(4) bioactivation, was investigated. Treatment with CAPE significantly decreased the CYP2E1-dependent hydroxylation of aniline. In addition, CAPE attenuated the CCl(4)-mediated depletion of antioxidant enzyme (catalase, superoxide dismutase and glutathione-S-transferase) activities. These findings suggest that the protective effects of CAPE against CCl(4)-induced acute liver injury may involve its ability to block CYP2El-mediated CCl(4) bioactivation and to protect against Fas/FasL-mediated apoptosis.
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PMID:Protective effect of caffeic acid phenethyl ester against carbon tetrachloride-induced hepatotoxicity in mice. 1843 64

The purpose of this study was to determine the differential effects of therapeutic X-radiation on constituent bone cells relative to the pediatric tumor cells: Ewing's sarcoma of bone and rhabdomyosarcoma. In addition, the radioprotectant drugs amifostine and sodium selenite were administered to constituent bone cells and the two tumor cells to determine if the radioprotectants differentially protect bone cells while not benefiting the tumor cells. These studies are a necessary first step in determining the potential clinical benefit of radioprotective therapy. An established in vitro cell culture model employing both constituent bone cells (osteoblasts, primary bone marrow monocytes, osteoclasts chondrocytes, and endothelial cells) and the tumor cells lines (Ewing's sarcoma of bone and rhabdomyosarcoma) were exposed to irradiation, amifostine, and sodium selenite. Cells were then assayed for changes in cell number, cytotoxicity, mineralization, bone resorption, cell attachment, osteocalcin, caspase-3 expression, clonogenic survival, and alkaline phosphatase expression. Radiation therapy differentially decreased cell number; with osteoblasts being shown to be the least sensitive to irradiation, the tumor cells had an intermediate sensitivity and monocytes were the most sensitive. Both amifostine and sodium selenite protected chondrocytes and osteoblasts from the negative effects of irradiation, while not protecting the tumor cells. The pediatric tumor cell lines were generally more radiosensitive than the bone cells examined. The radioprotectant drugs amifostine and sodium selenite provided significant radioprotection to constituent bone cells while not protecting the tumor cells. Finally, amifostine and sodium selenite therapy provided an additional benefit beyond radioprotection by increasing cytotoxicity in nonirradiated and irradiated tumor cells.
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PMID:The differential effects of the radioprotectant drugs amifostine and sodium selenite treatment in combination with radiation therapy on constituent bone cells, Ewing's sarcoma of bone tumor cells, and rhabdomyosarcoma tumor cells in vitro. 1847 85

We examined the effects of polyarticular juvenile idiopathic arthritis (pJIA) serum on proliferation, differentiation, mineralization, and apoptosis of human osteoblast cells (hOb) in culture. The hOb were cultured with 10% serum from active pJIA and healthy controls (CT) and were tested for DNA synthesis, alkaline phosphatase (AP) activity, osteocalcin (OC) secretion, calcium levels, caspase 3 activity, and DNA fragmentation. None of the patients had used glucocorticoids for at least 1 month before the study, or any other drug that can affect bone mineral metabolism. Human inflammatory cytokine levels (IL-6, IL-8, IL-10, IL-1beta, TNF-alpha, and IL-12p70) were measured in pJIA and CT sera. Low levels of AP activity was observed in pJIA cultures compared with CT cultures (67.16 +/- 53.35 vs 100.11 +/- 50.64 mumol p-nitrophenol/h(-1) mg(-1) protein, P = 0.008). There was also a significant decrease in OC secretion (9.23 +/- 5.63 vs 12.82 +/- 7.02 ng/mg protein, P = 0.012) and calcium levels (0.475 +/- 0.197 vs 0.717 +/- 0.366 mmol/l, P = 0.05) in pJIA hOb cultures. No difference was observed in cell proliferation (323.56 +/- 108.23 vs 328.91 +/- 88.03 dpm/mg protein, P = 0.788). Osteoblasts cultured with JIA sera showed lower levels of DNA and increased fragmentation than osteoblasts cultured with CT sera. pJIA sera showed higher IL-6 values than CT (21.44 +/- 9.31 vs 3.58 +/- 2.38 pg/ml, P < 0.001), but no difference was observed related to IL-8, IL-10, IL-1beta, TNF-alpha, and IL-12p70 between pJIA and controls. This study suggests that serum from children with pJIA inhibits differentiation, mineralization and may increase apoptosis of hOb cultures, and inflammatory cytokines such as IL-6 might be a mechanism in this find. These results may represent an alternative therapeutic target for prevention and treatment of bone loss in JIA.
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PMID:Serum from children with polyarticular juvenile idiopathic arthritis (pJIA) inhibits differentiation, mineralization and may increase apoptosis of human osteoblasts "in vitro". 1868 81

The present study was undertaken to validate a battery of cytotoxicity assays performed in a multiplex format to screen pharmaceutical compounds at an early stage of drug development. Two experiments were performed on HepG2 cells and the parameters were measured in 96-well plates. Biological and technical triplicates were performed to evaluate the reproducibility of the assay. In the first experiment, HepG2 cells were exposed to tamoxifen, staurosporine, phenobarbital and triton X-100 for 2 and 24h. The following nine cytotoxicity parameters were analyzed, cell viability, lactate dehydrogenase (LDH), adenosine triphosphate (ATP), caspase-3/7, aspartate aminotransferase (AST), glutamate dehydrogenase (GLDH), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and alpha-glutathione-S-transferase (alpha-GST). In the second experiment, HepG2 cells were exposed to doxorubicin, t-butyl hydroperoxide, ferrous sulfate and sulfamoxole for 2 and 24h. Based on the results of the first experiment, six cytotoxicity parameters were selected for further evaluation (cell viability, ATP, LDH, caspase, AST and GLDH). ALT (activity always below detection limit), ALP (no response to drug treatment) and alpha-GST (too labor intensive and not possible to multiplex) were eliminated. The analysis of the data revealed that the reproducibility of the assays was accurate according to principal component analysis. Our data also clearly indicated that the potential of this battery of selected assays measured in a multiplex format not only made it possible to rank and select the most promising drug candidates based on their cytotoxic potential, but also to gather information that may help to understand some of the toxic events occurring in the cells.
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PMID:Selection of cytotoxicity markers for the screening of new chemical entities in a pharmaceutical context: a preliminary study using a multiplexing approach. 1911 50


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