OBJECTIVE: To observe whether HSP70 could protect against H2O2-induced apoptosis in C2C12 myogenic cells by inhibiting Smac release from the mitochondria. METHODS: HSP70 gene and full length Smac gene was transiently transfected in C2C12 myogenic cells by lipofectamine and the protein levels of HSP70 and Smac were analysed by Western blotting. Hoechst 33 258 staining was used to examine cell morphological changes and to calculate percentage of apoptotic nuclei. DNA ladder pattern on agarose gel electrophoresis was used to observe the DNA fragmentation. Activities of caspase-3 and caspase-9 were assayed with Western blotting. The release of Smac from the mitochondria to the cytoplasm was observed by immunofluorescence. RESULTS: H2O2 ( 0.5 mmol/L ) activated caspase-3, caspase-9 8 h after the treatment and specific morphological changes of apoptosis 12 h after the treatment, and overexpression of Smac significantly promoted H2O2-induced activation of caspase-3, caspase-9 and apoptosis in C2C12 myogenic cells. HSP70 overexpression significantly inhibited H2O2-induced and Smac-promoted apoptosis, as shown by no specific DNA ladder pattern in agarose gel electrophoresis, decrease of percentage of apoptotic nuclei, and marked inactivation of caspase-3 and caspase-9. HSP70 could inhibit the release of Smac from the mitochondria to the cytoplasm 2 h after the treatment by H2O2. CONCLUSION HSP70 inhibits Smac release from the mitochondria and protects against H2O2-induced apoptosis in C2C12 myogenic cells.
Apoptosis ; drug effects ; Apoptosis Regulatory Proteins ; Cells, Cultured ; HSP70 Heat-Shock Proteins ; pharmacology ; Humans ; Hydrogen Peroxide ; Intracellular Signaling Peptides and Proteins ; metabolism ; Mitochondria, Heart ; drug effects ; metabolism ; Mitochondrial Proteins ; antagonists & inhibitors ; metabolism ; Myoblasts ; metabolism ; Myocytes, Cardiac ; drug effects ; metabolism

OBJECTIVETo observe the anti-tumor effect of combination TNF-related apoptosis-inducing ligand (TRAIL) with aspirin on liver cancer cell line, SMMC-7721.

METHODSThe survival fraction of SMMC-7721 cells was measured by MTT assay, apoptosis rate and cell cycle was determined by flow cytometry, and the expression of apoptosis-related gene was identified by western blot.

RESULTSThe survival fraction of SMMC-7721 cells treated with 300 ng/ml TRAIL, 3 mmol/L or 10 mmol/L aspirin alone was 82.76%, 81.34% and 71.29% respectively, and the survival fractions of SMMC-7721 cells treated with TRAIL and 3 mmol/L or 10 mmol/L aspirin were 43.54% and 37.8% respectively. The apoptosis rates of SMMC-7721 cells induced by TRAIL and 3 mmol/L or 10 mmol/L aspirin were higher than that induced by TRAIL or aspirin alone (34.76% and 38.56% vs 21.25%, 1.89% and 6.08%), and G0/G1 arrest was observed under TRAIL and aspirin. The expression of Bcl-2 in SMMC-7721 cells treated by 3 mmol/L or 10 mmol/L aspirin decreased markedly, but no effect on Bax.

CONCLUSIONThe cooperative anti-tumor effect of aspirin and TRAIL may be related to the inhibition of the expression of Bcl-2 by aspirin

Antineoplastic Combined Chemotherapy Protocols ; pharmacology ; Apoptosis ; Apoptosis Regulatory Proteins ; Aspirin ; pharmacology ; Cell Survival ; drug effects ; Humans ; Membrane Glycoproteins ; pharmacology ; Proto-Oncogene Proteins c-bcl-2 ; antagonists & inhibitors ; TNF-Related Apoptosis-Inducing Ligand ; Tumor Cells, Cultured ; Tumor Necrosis Factor-alpha ; pharmacology

Auto-transplantation of adipose tissue is commonly used for the treatment of tissue defects in plastic surgery. The survival of the transplanted adipose tissue is not always constant, and one of reasons is the accelerated apoptosis of the implanted preadipocytes. We have recently established highly homogeneous preadipocytes, named ccdPAs. The aim of the current study was to evaluate the regulation of the potency of platelet-rich plasma (PRP) on the apoptosis of ccdPAs in vitro. PRP stimulated the proliferation of the preadipocytes in a dose-dependent manner, and the stimulatory activity of 2% PRP was significantly higher than that of 2% FBS or 2% platelet-poor plasma (PPP). The presence of 2% PRP significantly inhibited serum starvation- or TNF-alpha/cycloheximide-induced apoptosis in comparison to 2% FBS or 2% PPP. DAPK1 and Bcl-2-interacting mediator of cell death (BIM) mRNAs were reduced in the preadipocytes cultured with 2% PRP in comparison to those cultured in 2% FBS. The gene expression levels were significantly higher in cells cultured without serum in comparison to cells cultured with 2% FBS, and the levels in the cells with 2% PRP were reduced to 5-10% of those in the cells without serum. These results indicated that ccdPAs exhibit anti-apoptotic activities, in addition to increased proliferation, when cultured in 2% PRP in comparison to the same concentration of FBS, and that this was accompanied with reduced levels of DAPK1 and BIM mRNA expression in in vitro culture. PRP may improve the outcome of transplantation of adipose tissue by enhancing the anti-apoptotic activities of the implanted preadipocytes.
Adipocytes/*cytology ; Adipose Tissue/cytology/metabolism ; Apoptosis/*physiology ; Apoptosis Regulatory Proteins/antagonists & inhibitors/metabolism ; Calcium-Calmodulin-Dependent Protein Kinases/antagonists & inhibitors/metabolism ; Cell Culture Techniques/*methods ; *Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; Gene Expression Regulation ; Humans ; Membrane Proteins/antagonists & inhibitors/metabolism ; *Platelet-Rich Plasma/metabolism/physiology ; Proto-Oncogene Proteins/antagonists & inhibitors/metabolism ; Tissue Transplantation

OBJECTIVETo investigate therapeutic potential of TRAIL in hepatocellular carcinoma (HCC) and the mechanism of sTRAIL resistance and to reverse the resistance to sTRAIL-inducing apoptosis.

METHODSThe expression profiles of TRAILR were determined 60 HCC samples, in 20 normal liver tissues and 2 HCC cell lines HepG2 and SMMC-7721 by in situ hybridization. Cellular effects of sTRAIL in promoting apoptosis on HCC cell lines HepG2 and SMMC-7721 were analyzed after exposure to recombinant protein and after transfection with a cDNA expression construct. In vivo effects of sTRAIL on tumor growth were investigated using a nude mice HCC model of hepG2. Furthermore, the expression of survivin in HCC was detected, and treatment with antisence oligonucleotide was accepted. Finally, therapeutic effect on HCC by combining sTRAIL and interleukin-12 (IL-12) was detected.

RESULTSBoth DR4 and DR5 were present in all HCC tissues as well as normal hepatic tissues. In contrast, 54 HCC tissues did not express DcR1 and 25 did not express DcR2. But both DcR were detectable in all of the normal liver tissues. The expression patterns of DR and DcR in HCC samples were quite different from those in normal tissue. DR5, DR4, and DcR2 expressed in both cell lines, while no DcR1 expression was detected. Recombinant sTRAIL alone was found to have a slight activity as it killed a maximum of 15% of HCC cells within 24 h while killing over 70% of Jurkat cells. In vivo administration of the TRAIL gene couldn't inhibit tumor growth in a nude mice HCC model. Mostly, HCC tissue and both HCC cell lines expressed survivin, whereas normal liver tissue did not express survivin. Treatment with antisence oligonucleotide enhanced sTRAIL-inducing apoptosis. IL-12 significantly augmented sTRAIL-inducing apoptosis and inhibited survivin expression.

CONCLUSIONSHCC cells are insensitive towards TRAIL-mediated apoptosis. Survivin may play a role in resistance to TRAIL-induced apoptosis in HCC, and antisence oligonucleotide could partly reverse the resistance to TRAIL-inducing apoptosis. IL-12 may sensitize HCC cells to TRAIL-induced apoptosis by preventing survivin. Combining gene therapy strategy such as combining gene therapy of TRAIL with IL-12 may be a promising maneuver to HCC.

Animals ; Apoptosis ; drug effects ; Apoptosis Regulatory Proteins ; Carcinoma, Hepatocellular ; pathology ; therapy ; Cell Line, Tumor ; Genetic Therapy ; Humans ; Inhibitor of Apoptosis Proteins ; Interleukin-12 ; administration & dosage ; genetics ; Liver Neoplasms ; pathology ; therapy ; Membrane Glycoproteins ; administration & dosage ; genetics ; Mice ; Mice, Nude ; Microtubule-Associated Proteins ; antagonists & inhibitors ; Neoplasm Proteins ; Recombinant Proteins ; administration & dosage ; TNF-Related Apoptosis-Inducing Ligand ; Transfection ; Tumor Necrosis Factor-alpha ; administration & dosage ; genetics

OBJECTIVETo investigate the effect of aurora kinase inhibitor ENMD-2076 on human acute myelogenous leukemia (AML) cell lines.

METHODSAML THP-1 and Kasumi-1 cells were treated with ENMD-2076 for 24 h and 48 h,respectively. Cell growth was measured by MTT assay. Apoptosis was determined using Hoechst staining apoptosis detection kit. Activation of Caspase pathway and expression of apoptosis regulator proteins were detected by Western blot.

RESULTSENMD-2076 significantly induced growth arrest and apoptosis in THP-1 and Kasumi-1 cells. Enhanced apoptosis was observed in ENMD-2076 group evidenced by strong activation of Caspase-9,Caspase-3 and PARP. Furthermore,the ENMD-2076 treatment resulted in down-regulation of anti-apoptotic protein Mcl-1 expression. Also,up-regulated expression of pro-apoptotic protein Bak,Bad and Bax was detected after ENMD-2076 treatment.

CONCLUSIONENMD-2076 can kill effectively AML cells by inhibiting cell growth and inducing apoptosis,which is associated with activation of Caspase pathway and regulation of pro-apoptotic and anti-apoptotic proteins.

Apoptosis ; drug effects ; Apoptosis Regulatory Proteins ; metabolism ; Aurora Kinases ; Caspases ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Humans ; Leukemia, Myeloid, Acute ; metabolism ; pathology ; Protein-Serine-Threonine Kinases ; antagonists & inhibitors ; Pyrazoles ; pharmacology ; Pyrimidines ; pharmacology

The present study was to investigate whether Toll-like receptor 4 (TLR4)-mediated Akt/FoxO3a/Bim signaling pathway participated in lipopolysaccharide (LPS)-induced apoptosis in hippocampal neurons. The primarily cultured rat hippocampal neurons were treated with LPS, TLR4 antibody+LPS, and LY294002+LPS, respectively. Cell vitality was assayed by CCK-8. Expressions of p-Akt, Akt, p-FoxO3a, FoxO3a, Bim and active-Caspase-3 of each group were detected by Western blot analysis; the mRNA expression of Bim was detected by real-time quantitative PCR; FoxO3a nuclear translocation was detected by fluorescence microscope. The rate of cell apoptosis was assayed by flow cytometry. The results showed that cell vitality of hippocampal neurons decreased after being treated with LPS in a time-dependent way. Compared with the control group, the expressions of p-Akt and p-FoxO3a decreased significantly, FoxO3a translocated into the nucleus, meanwhile, the expression of Bim and active-Caspase-3, and the apoptotic ratio of hippocampal neurons increased in LPS treated neurons. Pretreatment with TLR4 antibody significantly blocked, while PI3K antagonist LY294002 further strengthened these changes induced by LPS. In conclusion, the present study suggests that Akt/FoxO3a/Bim signaling pathways mediated by TLR4 participate in the apoptotic processes of primarily cultured hippocampal neurons treated with LPS, and the activation of TLR4 causes neuronal apoptosis.
Animals ; Apoptosis ; Apoptosis Regulatory Proteins ; metabolism ; Bcl-2-Like Protein 11 ; Caspase 3 ; metabolism ; Chromones ; pharmacology ; Forkhead Box Protein O3 ; Forkhead Transcription Factors ; metabolism ; Hippocampus ; cytology ; Lipopolysaccharides ; Membrane Proteins ; metabolism ; Morpholines ; pharmacology ; Neurons ; cytology ; metabolism ; Phosphatidylinositol 3-Kinases ; antagonists & inhibitors ; Proto-Oncogene Proteins ; metabolism ; Proto-Oncogene Proteins c-akt ; metabolism ; Rats ; Signal Transduction ; Toll-Like Receptor 4 ; metabolism

Autophagy is a conserved and programmed catabolic process that degrades damaged proteins and organelles. But the underlying mechanism and functions of autophagy in the ischemia-reperfusion (IR)-induced injury are unknown. In this study, we employed simulated IR of N2a cells as an in vitro model of IR injury to the neurons and monitored autophagic processes. It was found that the levels of Beclin-1 (a key molecule of autophay complex, Beclin-1/class III PI3K) and LC-3II (an autophagy marker) were remarkably increased with time during the process of ischemia and the process of reperfusion after 90 min of ischemia, while the protein kinases p70S6K and mTOR which are involved in autophagy regulation showed delayed inactivation after reperfusion. Administration of 3-methyladenine (3MA), an inhibitor of class III PI3K, abolished autophagy during reperfusion, while employment of rapamycin, an inhibitor of mTORC1 (normally inducing autophagy), surprisingly weakened the induction of autophagy during reperfusion. Analyses of mitochondria function by relative cell viability demonstrated that autophagy inhibition by 3-MA attenuated the decline of mitochondria function during reperfusion. Our data demonstrated that there were two distinct dynamic patterns of autophagy during IR-induced N2a injury, Beclin-1/class III PI3K complex-dependent and mTORC1-dependent. Inhibition of over-autophagy improved cell survival. These suggest that targeting autophagy therapy will be a novel strategy to control IR-induced neuronal damage.
Adenine ; analogs & derivatives ; pharmacology ; Animals ; Apoptosis Regulatory Proteins ; genetics ; metabolism ; Autophagy ; Beclin-1 ; Cell Line, Tumor ; Cell Survival ; Mechanistic Target of Rapamycin Complex 1 ; Mice ; Mitochondria ; metabolism ; Multiprotein Complexes ; antagonists & inhibitors ; metabolism ; Neurons ; drug effects ; metabolism ; Neuroprotective Agents ; pharmacology ; Phosphatidylinositol 3-Kinases ; antagonists & inhibitors ; metabolism ; Reperfusion Injury ; metabolism ; Sirolimus ; pharmacology ; TOR Serine-Threonine Kinases ; antagonists & inhibitors ; metabolism

Inadequate apoptosis contributes to synovial hyperplasia in rheumatoid arthritis (RA). Recent study shows that low expression of Puma might be partially responsible for the decreased apoptosis of fibroblast-like synoviocytes (FLS). Slug, a highly conserved zinc finger transcriptional repressor, is known to antagonize apoptosis of hematopoietic progenitor cells by repressing Puma transactivation. In this study, we examined the expression and function of Slug in RA FLS. Slug mRNA expression was measured in the synovial tissue (ST) and FLS obtained from RA and osteoarthritis patients. Slug and Puma mRNA expression in FLS by apoptotic stimuli were measured by real-time PCR analysis. FLS were transfected with control siRNA or Slug siRNA. Apoptosis was quantified by trypan blue exclusion, DNA fragmentation and caspase-3 assay. RA ST expressed higher level of Slug mRNA compared with osteoarthritis ST. Slug was significantly induced by hydrogen peroxide (H2O2) but not by exogenous p53 in RA FLS. Puma induction by H2O2 stimulation was significantly higher in Slug siRNA-transfected FLS compared with control siRNA-transfected FLS. After H2O2 stimulation, viable cell number was significantly lower in Slug siRNA-transfected FLS compared with control siRNA-transfected FLS. Apoptosis enhancing effect of Slug siRNA was further confirmed by ELISA that detects cytoplasmic histone-associated DNA fragments and caspase-3 assay. These data demonstrate that Slug is overexpressed in RA ST and that suppression of Slug gene facilitates apoptosis of FLS by increasing Puma transactivation. Slug may therefore represent a potential therapeutic target in RA.
Apoptosis/*drug effects/genetics ; Apoptosis Regulatory Proteins/*genetics/metabolism ; Arthritis, Rheumatoid/genetics/metabolism/*pathology ; Cells, Cultured ; Drug Evaluation, Preclinical ; Fibroblasts/drug effects/metabolism/pathology ; Humans ; Hydrogen Peroxide/*pharmacology ; Proto-Oncogene Proteins/*genetics/metabolism ; RNA, Small Interfering/*pharmacology ; Synovial Membrane/cytology/drug effects/metabolism/*pathology ; Transcription Factors/*antagonists & inhibitors/genetics ; Transcriptional Activation/drug effects ; Transfection

OBJECTIVETo observe the sensitivity change of SMMC-7721 cells transfected with antisense DNMT1 gene fragment to tumor necrosis factor related apoptosis inducing ligand (TRAIL) and its mechanism.

METHODSCell survival rate was measured by trypan blue, apoptosis rate by TUNEL method and the expression of bcl-2, bax and bad by flow cytometry.

RESULTSCell survival rate of SMMC-7721 cells transfected with antisense DNMT1 gene fragment was markedly lower than that transfected with sense DNMT1 gene fragment or empty vector (P < 0.05 and 0.01), but the apoptosis rate was on the contrary (P < 0.05 or 0.01). The expression of bax and bad (especially the former), but not bcl-2 of SMMC-7721 cells transfected with antisense DNMT1 gene fragment was markedly higher than those of SMMC-7721 cells transfected with sense DNMT1 gene fragment or empty vector.

CONCLUSIONThe sensitivity of SMMC-7721 cells to TRAIL can be enhanced by the transfection of antisense DNMT1 gene fragment, which may be related to the increase of bax and bad expression.

Antisense Elements (Genetics) ; genetics ; Apoptosis ; drug effects ; Apoptosis Regulatory Proteins ; Carrier Proteins ; analysis ; Cell Line, Tumor ; DNA (Cytosine-5-)-Methyltransferase 1 ; DNA (Cytosine-5-)-Methyltransferases ; antagonists & inhibitors ; genetics ; Flow Cytometry ; Humans ; Liver Neoplasms ; metabolism ; pathology ; Membrane Glycoproteins ; pharmacology ; Proto-Oncogene Proteins ; analysis ; Proto-Oncogene Proteins c-bcl-2 ; TNF-Related Apoptosis-Inducing Ligand ; Tumor Necrosis Factor-alpha ; pharmacology ; bcl-2-Associated X Protein ; bcl-Associated Death Protein

NADPH oxidase produces a large amount of reactive oxygen species (ROS) in Helicobacter pylori (H. pylori)-induced gastric epithelial cells. Even though ROS mediate apoptotic cell death, direct involvement of NADPH oxidase on H. pylori-induced apoptosis remains unclear. Besides, H. pylori isolates show a high degree of genetic variability. The predominant genotype of H. pylori in Korea has been reported as cagA+, vacA s1b, m2, iceA genotype. Present study aims to investigate whether NADPH oxidase-generated ROS mediate apoptosis in human gastric epithelial AGS cells infected with H. pylori in a Korean isolate. AGS cells were pretreated with or without an NADPH oxidase inhibitor diphenyleneiodonium (DPI) and cultured in the presence of H. pylori at a bacterium/cell ratio of 300:1. Cell viability, hydrogen peroxide level, DNA fragmentation, and protein levels of p53, Bcl-2, and Bax were determined. Results showed that H. pylori inhibited cell viability with the density of H. pylori added to the cells. Inhibition of NADPH oxidase by DPI suppressed H. pylori-induced cell death, increased hydrogen peroxide, DNA fragmentation, and the ratio of Bax/Bcl-2, and p53 induction in AGS cells dose-dependently. The results suggest that targeting NADPH oxidase may prevent the development of gastric inflammation associated with H. pylori infection by suppressing abnormal apoptotic cell death of gastric epithelial cells.
Apoptosis ; Apoptosis Regulatory Proteins/metabolism ; Cell Survival ; Epithelial Cells/metabolism/microbiology ; Gastric Mucosa/metabolism ; Helicobacter Infections/*metabolism/microbiology ; Helicobacter pylori/drug effects/genetics/*isolation & purification ; Humans ; NADPH Oxidase/metabolism ; Onium Compounds/*antagonists & inhibitors/pharmacology ; Oxidative Stress/drug effects ; Reactive Oxygen Species/metabolism ; Republic of Korea ; Stomach/cytology/*metabolism/microbiology