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

This study investigated effects of Ginsenoside Ro (Ro) on interleukin-1β (IL-1β)-induced apoptosis and inflammation in rat chondrocytes. The rat chondrocytes were co-treated with IL-1β (10 ng·kg(-1)) and Ro (50, 100 and 200 μmol·L(-1)) for 48 h. Chondrocytes viability was detected by the MTT assay and Annexin V-FITC/PI dual staining assay. Caspase 3 activity was measured by using caspase 3 colorimetric assay kit. Apoptosis related proteins Bax, Bad, Bcl-xL, PCNA, p53 and phospho-p53, along with inflammation related protein MMP 3, MMP 9 and COX-2, and the expression of phospho-NF-κB p65 were assayed by western blotting analyses. Ro could improve IL-1β-induced chondrocytes viability. Ro could suppress IL-1β-induced apoptosis by inhibiting levels of Bax and Bad, decreasing p53 phosphorylation and promoting the expression of Bcl-xL and PCNA. Ro inhibited caspase 3 activity. IL-1β-induced inflammation and matrix degration were also alleviated by Ro with down-regulating the expression of MMP 3, MMP 9 and COX-2. Moreover, Ro inhibited NF-κB p65 phosphorylation induced by IL-1β. In conclusion, these results suggested Ro exerted anti-apoptosis and anti-inflammation in IL-1β-induced rat chondrocytes, which might be related to NF-κB signal pathway. Therefore, we propose that Ro might be a potential novel drug for the treatment of osteoarthritis.
Animals ; Anti-Inflammatory Agents ; pharmacology ; Apoptosis ; drug effects ; Apoptosis Regulatory Proteins ; drug effects ; metabolism ; Caspase 3 ; metabolism ; Cell Survival ; drug effects ; Chondrocytes ; cytology ; drug effects ; Cyclooxygenase 2 ; drug effects ; metabolism ; Down-Regulation ; drug effects ; Drug Evaluation, Preclinical ; Ginsenosides ; pharmacology ; Inflammation ; chemically induced ; drug therapy ; Interleukin-1beta ; antagonists & inhibitors ; pharmacology ; Matrix Metalloproteinase 3 ; drug effects ; metabolism ; Matrix Metalloproteinase 9 ; drug effects ; NF-kappa B ; antagonists & inhibitors ; drug effects ; metabolism ; Phosphorylation ; drug effects ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; drug effects

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 plays important roles in modulating viral replication and antiviral immune response. Coronavirus infection is associated with the autophagic process, however, little is known about the mechanisms of autophagy induction and its contribution to coronavirus regulation of host innate responses. Here, we show that the membrane-associated papain-like protease PLP2 (PLP2-TM) of coronaviruses acts as a novel autophagy-inducing protein. Intriguingly, PLP2-TM induces incomplete autophagy process by increasing the accumulation of autophagosomes but blocking the fusion of autophagosomes with lysosomes. Furthermore, PLP2-TM interacts with the key autophagy regulators, LC3 and Beclin1, and promotes Beclin1 interaction with STING, the key regulator for antiviral IFN signaling. Finally, knockdown of Beclin1 partially reverses PLP2-TM's inhibitory effect on innate immunity which resulting in decreased coronavirus replication. These results suggested that coronavirus papain-like protease induces incomplete autophagy by interacting with Beclin1, which in turn modulates coronavirus replication and antiviral innate immunity.
Apoptosis Regulatory Proteins ; antagonists & inhibitors ; genetics ; immunology ; Autophagy ; Beclin-1 ; Coronavirus NL63, Human ; genetics ; immunology ; Gene Expression Regulation ; HEK293 Cells ; HeLa Cells ; Host-Pathogen Interactions ; immunology ; Humans ; Immune Evasion ; Immunity, Innate ; Interferon-gamma ; genetics ; immunology ; Lysosomes ; metabolism ; virology ; MCF-7 Cells ; Membrane Fusion ; Membrane Proteins ; antagonists & inhibitors ; genetics ; immunology ; Microtubule-Associated Proteins ; genetics ; immunology ; Papain ; genetics ; immunology ; Phagosomes ; metabolism ; virology ; RNA, Small Interfering ; genetics ; immunology ; Signal Transduction ; Virus Replication

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

Autophagy, an evolutionarily conserved lysosomal degradation process, has drawn an increasing amount of attention in recent years for its role in a variety of human diseases, such as cancer. Notably, autophagy plays an important role in regulating several survival and death signaling pathways that determine cell fate in cancer. To date, substantial evidence has demonstrated that some key autophagic mediators, such as autophagy-related genes (ATGs), PI3K, mTOR, p53, and Beclin-1, may play crucial roles in modulating autophagic activity in cancer initiation and progression. Because autophagy-modulating agents such as rapamycin and chloroquine have already been used clinically to treat cancer, it is conceivable that targeting autophagic pathways may provide a new opportunity for discovery and development of more novel cancer therapeutics. With a deeper understanding of the regulatory mechanisms governing autophagy, we will have a better opportunity to facilitate the exploitation of autophagy as a target for therapeutic intervention in cancer. This review discusses the current status of targeting autophagic pathways as a potential cancer therapy.
Antibiotics, Antineoplastic ; therapeutic use ; Apoptosis Regulatory Proteins ; metabolism ; Autophagy ; drug effects ; genetics ; Beclin-1 ; Chloroquine ; therapeutic use ; Drug Discovery ; Humans ; Membrane Proteins ; metabolism ; Molecular Targeted Therapy ; Neoplasms ; metabolism ; pathology ; therapy ; Phosphatidylinositol 3-Kinases ; antagonists & inhibitors ; metabolism ; Signal Transduction ; Sirolimus ; therapeutic use ; TOR Serine-Threonine Kinases ; metabolism ; Tumor Suppressor Protein p53 ; metabolism

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 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

OBJECTIVETo explore correlation of seven apoptosis-related proteins (Hsp90a, p53, MDM2, Bcl-2, Bax, Cytochrome C, and Cleaved caspase3) with clinical outcomes of ALK+ anaplastic large-cell lymphoma (ALCL).

METHODSUsing immunohistochemistry and immunofluorescence double staining methods, the expressions of these seven apoptosis-associated proteins were studied to clarify their relationship with clinical outcomes of 36 ALK+ and 25 ALK-systemic ALCL patients enrolled between 1996 and 2006. The relationship of these apoptosis-regulating proteins with NPM-ALK status was also evaluated with the tyrosine inhibitor herbimycin A (HA) in vitro by immunocytochemistry, Western blotting and flow cytometric assays.

RESULTSThe presence of Hsp90α-, MDM2-, Bax-, Cytochrome C, and Cleaved caspase3-positive tumor cells was found significantly different in ALK+ and ALK-ALCLs, which was correlated with highly favorable clinical outcome. The Bcl-2- and p53-positive tumor cells were found in groups of patients with unfavorable prognosis. Inhibition of NPM-ALK by HA could reactivate the p53 protein and subsequent apoptosis-related proteins and therefore induced apoptosis in ALK+ ALCL cells.

CONCLUSIONOur results suggest that these seven proteins might be involved in apoptosis regulation and associated with clinical outcome of ALK+ systemic ALCLs. We also reveal a dynamic chain relation that NPM-ALK regulates p53 expression and subsequent apoptosis cascade in ALK+ ALCLs.

Adolescent ; Adult ; Aged ; Apoptosis ; drug effects ; Apoptosis Regulatory Proteins ; metabolism ; Benzoquinones ; pharmacology ; Biomarkers, Tumor ; metabolism ; Blotting, Western ; Cell Culture Techniques ; Cell Survival ; drug effects ; Child ; Child, Preschool ; Disease-Free Survival ; Enzyme Inhibitors ; pharmacology ; Female ; Flow Cytometry ; Humans ; Immunohistochemistry ; Kaplan-Meier Estimate ; Lactams, Macrocyclic ; pharmacology ; Lymphoma, Large-Cell, Anaplastic ; enzymology ; metabolism ; pathology ; Male ; Microscopy, Fluorescence ; Middle Aged ; Neoplasm Staging ; Prognosis ; Protein-Tyrosine Kinases ; metabolism ; Receptor Protein-Tyrosine Kinases ; antagonists & inhibitors ; metabolism ; Retrospective Studies ; Rifabutin ; analogs & derivatives ; Young Adult

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