OBJECTIVETo investigate the apoptosis of J774A.1 cells induced by Leptospira interrogans and the effect of caspase-3, -6 activation on the apoptosis.

METHODSMouse monocyte-macrophage like cell line J774A.1 was infected by L.interrogans serogroup Icterohaemorrhagiae serovar icterohaemorrhagiae Lai strain 56601. The apoptosis or necrosis of infected cells was examined by flow cytometry using fluorescein labeling FITC-Annexin V/PI. The activity of caspase-3, -6, and their cleaved substrates PARP and Lamin A/C were measured by fluorometry and Western Blotting, respectively.

RESULTL. interrogans strain Lai was able to induce apoptosis of J774A.1 cells and the maximal apoptotic rate was(48.81+/-5.95)% when microbe: cell ratio was 100: 1. The maximal activities of caspase-3 and -6 in the infected J774A.1 cells were (1453.41+/-36.07) and (618.65+/-39.82) FU, respectively, which were 16.38- and 9.98-fold of those uninfected cells. PARP and Lamin A/C in the infected cells were detected. Caspase-3 and -6 inhibitors remarkably blocked the L. interrogans-induced apoptosis in J774A.1 cells.

CONCLUSIONL. interrogans is able to induce the apoptosis of J774A.1 cells and intracellular caspase-3 and -6 are closely associated with the apoptosis.

Animals ; Apoptosis ; Caspase 3 ; metabolism ; Caspase 6 ; metabolism ; Cell Line ; Leptospira interrogans ; pathogenicity ; Macrophages ; enzymology ; microbiology ; pathology ; Mice

OBJECTIVETo evaluate if caspase pathway was involved in streptomycin-induced cell apoptosis in cochlear hair cells.

METHODSF344 rats at postnatal day 3 or 4 were used for the study in cochlear organotypic cultures. The cochlear basilar membrane was micro-dissected out and cultured overnight, and then treated with 1 mmol/L streptomycin for 24 hours. Before the termination, the activity of caspase-8, 9 or 6 were detected with FAM-peptide-FMK labeled caspase-8, 9 or 6, respectively. The stereocilia and cuticular plate of hair cells were stained with TRITC conjugated phalloidin, and the nuclei were stained with Topro-3 DNA probe. The specimens were observed and photographed under confocal fluorescent microscope.

RESULTSStreptomycin with 1 mmol/L causes about 80% cochlear hair cells missing in the basal turn and 10% hair cell loss in the apex. After streptomycin treatment, the nuclear shrinkage and fragmentation were found in most cochlear hair cells, and the caspase-8, caspase-9 and caspase-6 were greatly activated.

CONCLUSIONSApoptosis is involved in the cochlear hair cells death induced by Streptomycin in vitro. The caspase activities in upstream and downstream are maybe the major apoptotic pathway.

Animals ; Apoptosis ; drug effects ; Caspase 6 ; metabolism ; Caspase 8 ; metabolism ; Caspase 9 ; metabolism ; Cells, Cultured ; Hair Cells, Auditory ; cytology ; drug effects ; Rats ; Rats, Inbred F344 ; Streptomycin ; adverse effects

Sphingosine kinase 1 and its product, sphingosine 1-phosphate (S1P), as well as their receptors, have been implicated in inflammatory responses. The functions of receptors S1P₁ and S1P₂ on cell motility have been investigated. However, the function of S1P₃ has been poorly investigated. In this study, the roles of S1P₃ on inflammatory response were investigated in primary perito-neal macrophages. S1P₃ receptor was induced along with sphingosine kinase 1 by stimulation of lipopolysaccharide (LPS). LPS treatment induced inflammatory genes, such iNOS, COX-2, IL-1β, IL-6 and TNF-α. TY52156, an antagonist of S1P₃ suppressed the induction of inflammatory genes in a concentration dependent manner. Suppression of iNOS and COX-2 induction was further confirmed by western blotting and NO measurement. Suppression of IL-1β induction was also confirmed by western blotting and ELISA. Caspase 1, which is responsible for IL-1β production, was similarly induced by LPS and suppressed by TY52156. Therefore, we have shown S1P₃ induction in the inflammatory conditions and its pro-inflammatory roles. Targeting S1P₃ might be a strategy for regulating inflammatory diseases.
Blotting, Western ; Caspase 1 ; Cell Movement ; Enzyme-Linked Immunosorbent Assay ; Inflammation ; Interleukin-6 ; Macrophages ; Phosphotransferases ; Sphingosine

Mammalian cell is critically dependent on a continuous supply of oxygen. Even brief periods of oxygen deprivation can result in profound cellular damage. The aim of this study was to examine the possible mechanism of apoptosis in response to hypoxia in MC3T3E1 osteoblasts. MC3T3E1 osteoblasts under hypoxic conditions (2% oxygen) resulted in apoptosis in a time-dependent manner, determined by DNA fragmentation assay and nuclear morphology, stained with fluorescent dye (Hoechst 33258) Pretreatment with Z-VAD-FMK, a pan-caspase inhibitor, or Z-DEVD-CHO, a specific caspase-3 inhibitor, suppressed the DNA ladder in response to hypoxia in a concentration-dependent manner. An increase in caspase-3-like protease (DEVDase) activity was observed during apoptosis, but no caspase-1 activity (YVADase) was detected. To confirm what caspases were involved in apoptosis, western blot analysis was performed using an anti-caspase-3 or 6 antibody. The 17-kDa protein, that corresponds to the active products of caspase-3 and the 20-kDa protein of the active protein of caspase-6 were generated in hypoxia-challenged lysates, in which the full length forms of caspase-3 and 6 were evident. With a time course similar to caspase-3 and 6 activation, hypoxic stress also caused the cleavage of Lamin A, typical of caspase-6 activity. In addition, the hypoxic stress elicited the release of cytochrome c into the cytosol during apoptosis. These findings suggested that the activation of caspases accompanied by a cytochrome c release in response to hypoxia was involved in apoptotic cell death in MC3T3E1 osteoblasts.
Anoxia* ; Apoptosis* ; Blotting, Western ; Caspase 3 ; Caspase 6 ; Caspases ; Cell Death ; Cytochromes c ; Cytosol ; DNA ; DNA Fragmentation ; Lamin Type A ; Osteoblasts* ; Oxygen ; Signal Transduction*

It was reported that cancer in humans and animals infected with microbial pathogens was regressed about 100 years ago. Bacteria are able to trigger apoptosis by a variety of mechanisms including the secretion of protein synthesis inhibitors, pore forming proteins, molecules activating the endogenous death machinery in the infected cell. This study was conducted in order to investigate whether extracellular products of Psuedomonas aeruginosa (EPPA) induce apoptosis in human oral carcinoma cells (OSC9). The EPPA showed cytotoxic effect on OSC9 cells in dose and time-dependent manner. The cell death was demonstrated to be due to apoptosis characterized by chromatin condensation and nuclear fragment. EPPA treatment induced cleavage of caspase-3 and caspase-6. The caspase substrates, PARP, DFF45 and lamin A were cleaved during EPPA-induced apoptosis. Taken together, EPPA induces apoptosis on human oral squamous carcinoma cells in caspase-dependent manner. Our data therefore provide that EPPA contains a novel antitumor agent for human oral squamous carcinoma.
Animals ; Apoptosis* ; Bacteria ; Carcinoma, Squamous Cell* ; Caspase 3 ; Caspase 6 ; Cell Death ; Chromatin ; Humans* ; Lamin Type A ; Protein Synthesis Inhibitors ; Pseudomonas aeruginosa* ; Pseudomonas*

BACKGROUND AND OBJECTIVES: To reveal the detail mechanism of miR-484 on myocardial ischemia-reperfusion (MI/R) injury.METHODS: Rats model of MI/R injury was established based on control (Con; sham operate) group, ischemia-reperfusion (I/R) group, miR-484 treatment (miR) group, and I/R-negative control (IR-C) group, followed by pathological and interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-1β expression evaluation. Then the myocardial apoptosis, as well as the expression of miR-484, caspase-3, and caspase-9 in myocardium were examined. Finally, the regulatory relation between miR-484 and SMAD family member 7 (SMAD7) was predicated, followed by verification analysis.RESULTS: Compared with Con group, the expression of miR-484 in I/R and IR-C group was decreased. Compared with I/R and IR-C group, the expression of miR-484 was increased in miR group. Compared with Con group, the expression levels of IL-6, TNF-α, and IL-1β in cardiac myocytes of I/R group and IR-C group were increased. Compared with Con group, the apoptotic index, membrane potential of I/R, and the expression of caspase-3/9 were increased in IR-C group. Compared with the I/R and IR-C groups, the apoptotic index of myocardial cells in the ischemic region was decreased, the membrane potential was increased, and the expression of caspase-3/9 was decreased significantly in the miR group. SMAD7 was the target gene of miR-484.CONCLUSIONS: MiR-484 protected myocardial cells from I/R injury by suppressing caspase-3 and caspase-9 expression during cardiomyocyte apoptosis. MiR-484 reduced the expression of IL-6, TNF-α, and IL-1β in MI/R. MiR-484 might alleviate the decreasing of mitochondrial membrane potential in MI/R cells.
Animals ; Apoptosis ; Caspase 3 ; Caspase 9 ; Humans ; Interleukin-6 ; Interleukins ; Membrane Potential, Mitochondrial ; Membrane Potentials ; Myocardium ; Myocytes, Cardiac ; Rats ; Reperfusion Injury ; Tumor Necrosis Factor-alpha

OBJECTIVETo explore the inhibition of Jumi (traditional Chinese medicine) extraction on the growth of human cervical cancer cell line HeLa.

METHODSNude mouse model of human cervical cancer HeLa cell transplantation was established. The nude mice bearing cancer were randomly divided into control group and Jumi treated groups with different concentration (0.001, 0.002, 0.005, 0.01 mg/ml). The growth of cervical cancer cell in experimental mice were measured. Cultured HeLa cells were incubated in culture media with or without Jumi extract for 48 hours. Cell proliferation rate, cell apoptosis, caspase-3/7 and caspase-6 activity were determined by MTT colorimetric assay, flow cytometry analysis and spectrophotometric detection, respectively.

RESULTSWith the increase of the concentration of Jumi extract, tumor-bearing mice tumor inhibition rate gradually increased. The proliferation of cultured HeLa cells were significantly inhibited by Jumi extract in a dose-dependent manner. IC50 was 0.004 mg/ml. Apoptosis rates in the cells treated with Jumi extract were higher than those of the control group. Compared with the control group, except for lower Jumi treated group (0.001 mg/ml), caspase-3/7 and caspase-6 activity were significantly increased in the all Jumi treated groups.

CONCLUSIONJumi extract can inhibit the proliferation of human cervical cancer cell line HeLa in vitro in a dose-dependent manner and promote cell apoptosis through caspase-3, caspase-7 and caspase-6 pathway.

Animals ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Caspase 6 ; metabolism ; Caspase 7 ; metabolism ; Cell Proliferation ; drug effects ; Chrysanthemum ; Female ; HeLa Cells ; Humans ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Plant Extracts ; pharmacology ; Xenograft Model Antitumor Assays

AIMTo study the effects of caspases on cerebromicrovascular endothelial cell apoptosis induced by hypoxia in vitro.

METHODSThe cultured bovine cerebromicrovascular endothelial cells were exposed to NaCN in glucose-free medium. Cell viability was determined by trypan blue staining. Cell apoptosis was defined by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) and flow cytometry. The expression of caspase-3 was detected by immunocytochemical method. Four caspase inhibitors were used to validate the effect of caspases on cell apoptosis.

RESULTSNaCN in glucose-free medium initiated cerebromicrovascular endothelial cell injury markedly and typical apoptotic cells were found in this model. The expression of caspase-3 increased significantly. Four caspase inhibitors decreased the number of injured cells. Selective inhibitor of caspase-1 and -6 reduced expression of caspase-3 significantly.

CONCLUSIONThe results suggest that caspases family plays an important role in cerebromicrovascular endothelial cell apoptosis induced by NaCN and caspase-3 acts on the downstream of caspase-1 and -6 in protease cascade action to induce apoptosis.

Amino Acid Chloromethyl Ketones ; pharmacology ; Animals ; Apoptosis ; Brain ; blood supply ; Caspase 3 ; Caspase 6 ; Caspase Inhibitors ; Caspases ; metabolism ; Cattle ; Cell Hypoxia ; Cells, Cultured ; Endothelial Cells ; cytology ; metabolism ; Microcirculation ; cytology ; Oligopeptides ; pharmacology ; Sodium Cyanide ; pharmacology

Several studies have shown that curcumin, which is derived from the rhizomes of turmeric, possesses antimicrobial, antioxidant and anti-inflammatory properties. The antitumor properties of curcumin have also now been demonstrated more recently in different cancers. This study was undertaken to investigate the modulation of cell cycle-related proteins and the mechanisms underlying apoptosis induction by curcumin in the SCC25 human tongue squamous cell carcinoma cell line. Curcumin treatment of the SCC25 cells resulted in a time- and dose-dependent reduction in cell viability and cell growth, and onset of apoptotic cell death. The curcumin-treated SCC25 cells showed several types of apoptotic manifestations, such as nuclear condensation, DNA fragmentation, reduced MMP and proteasome activity, and a decreased DNA content. In addition, the treated SCC25 cells showed a release of cytochrome c into the cytosol, translocation of AIF and DFF40/CAD into the nuclei, a significant shift in the Bax/Bcl-2 ratio, and the activation of caspase-9, caspase-7, caspase-6, caspase-3, PARP, lamin A/C, and DFF45/ICAD. Furthermore, curcumin exposure resulted in a downregulation of G1 cell cycle-related proteins and upregulation of p27KIP1. Taken together, our findings demonstrate that curcumin strongly inhibits cell proliferation by modulating the expression of G1 cell cycle-related proteins and inducing apoptosis via proteasomal, mitochondrial, and caspase cascades in SCC25 cells.
Apoptosis* ; Carcinoma, Squamous Cell* ; Caspase 3 ; Caspase 6 ; Caspase 7 ; Caspase 9 ; Cell Cycle Checkpoints* ; Cell Death ; Cell Line* ; Cell Proliferation ; Cell Survival ; Curcuma ; Curcumin ; Cytochromes c ; Cytosol ; DNA ; DNA Fragmentation ; Down-Regulation ; Humans ; Proteasome Endopeptidase Complex ; Rhizome ; Tongue* ; Up-Regulation

Fluoride is widely used in dentistry to prevent dental caries, even though the safety of fluoride is a controversial issue. There are no known adverse effects of long-term fluoride ingestion for caries prevention, but an overdose can cause serious acute toxicity. Nevertheless it is accepted that fluoride is an important material for oral health. This study was undertaken to investigate the modulation of cell cycle-related proteins and apoptosis induction underlying mechanism by NaF treatment on G361 human melanoma cell line. The viability of G361 cells and the growth inhibition of G361 cells were assessed by MTT assay and clonogenic assay respectively. Hoechst staining, DNA electrophoresis and TUNEL staining were conducted to observe G361 cells undergoing apoptosis. G361 cells were treated with NaF, and Western blotting, immunocytochemistry, confocal microscopy, FACScan flow cytometry, MMP activity and proteasome activity were performed. NaF treatment in G361 cells resulted in a time- and does-dependent decrease of cell viability and a does-dependent inhibition of cell growth, and induced apoptotic cell death. And tested G361 cells showed several lines of apoptotic manifestation such as nuclear condensation, DNA fragmentation, the reduction of MMP and proteasome activity, the decrease of DNA contents, the release of cytochrome c into cytosol, the translocation of AIF and DFF40 (CAD) onto nuclei, a significant shift of Bax/Bcl-2 ratio, and the activation of caspase-9, caspase-7, caspase-6, caspase-3, PARP, Lamin A/C and DFF45 (ICAD). Furthermore, NaF resulted in down-regulation of the G1 cell cycle-related proteins, and up-regulation of p53. Taken collectively, our present findings demonstrate that NaF strongly inhibits cell proliferation by modulating the expression of the G1 cell cycle-related proteins and induces apoptosis via proteasome, mitochondria and caspase cascades in G361 cells.
Apoptosis ; Blotting, Western ; Caspase 3 ; Caspase 6 ; Caspase 7 ; Caspase 9 ; Cell Cycle ; Cell Cycle Checkpoints ; Cell Death ; Cell Line ; Cell Proliferation ; Cell Survival ; Cytochromes c ; Cytosol ; Dental Caries ; Dentistry ; DNA ; DNA Fragmentation ; Down-Regulation ; Eating ; Electrophoresis ; Flow Cytometry ; Fluorides ; Humans ; Immunohistochemistry ; In Situ Nick-End Labeling ; Melanoma ; Microscopy, Confocal ; Mitochondria ; Oral Health ; Proteasome Endopeptidase Complex ; Proteins ; Up-Regulation