OBJECTIVETo investigate the possible mechanism through which Artemisinin induced apoptosis in pancreatic cell line.

METHODSColumn chromatography, thin layer chromatography (TLC) and proton NMR spectroscopy were used to purify Artemisinin. The flowcytometry was employed to detect apoptosis and reactive oxygen species (ROS).

RESULTSThe results indicated that 50% inhibiting concentration (IC50 value) for pancreatic cell line (RIN) was 45 μmol/L of Artemisinin. Artemisinin had no cytotoxic effect on the growth of peripheral blood lymphocytes. The mechanism of apoptosis was evaluated by measuring intracellular ROS. It was shown that Artemisinin-induced apoptosis occurred independently of the binding of CD95L to CD95 receptor in the RIN cells. Moreover, Artemisinin, in a dose-dependent manner, could significantly increase the level of ROS.

CONCLUSIONArtemisinin can induce apoptosis in the RIN cells via the generation of ROS and triggering the intrinsic pathway of cell death.

Annexin A5 ; metabolism ; Apoptosis ; drug effects ; Artemisinins ; pharmacology ; Caspase 3 ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Colorimetry ; Flow Cytometry ; Humans ; Iron ; pharmacology ; Pancreatic Neoplasms ; enzymology ; pathology ; Propidium ; metabolism ; Proton Magnetic Resonance Spectroscopy ; Reactive Oxygen Species ; metabolism ; Time Factors ; fas Receptor ; metabolism

BACKGROUNDEndothelial cells derived microRNAs can be detected in plasma and serum and there is evidence that inflammatory disease states may affect the levels of circulating microRNAs. However, there is no direct proof that inflammation induces endothelial cells to release microRNAs into circulation. This study aimed to explore whether inflammation could induce endothelial cells to release microRNAs into circulation and to investigate whether these released microRNAs derived from endothelial cells were transported in microparticles.

METHODSMicroparticles were isolated from human atherosclerotic plaques with an active inflammatory phenotype and normal vascular tissue. Flow cytometry and real-time PCR were used to detect the levels of microparticles and microRNAs. Human umbilical vein endothelial cells (HUVEC) was treated with tumour necrosis factor a (TNF-α, 10 ng/ml) for 24 hours, and then HUVEC and the culture medium were respectively collected.

RESULTSBy comparing microparticles isolated from human atherosclerotic plaques with an active inflammatory phenotype (n = 9) and those from normal vascular tissues (n = 9), we found levels of annexin V(+) microparticles and annexin V(+) CD144(+) microparticles were significantly increased in plaques and angiogenesis associated microRNAs (106b, 25, 92a and 21) were also significantly increased in microparticles from plaques. After exposure to TNF-α at a concentration of 10 ng/ml (TNF-α group, n = 3) or DMEM (control group, n = 3) for 24 hours, counts of microparticles and expressions of microRNAs 106b, 25, 92a and 21 in microparticles isolated from medium significantly increased. However, there were no differences in the intracellular levels of microRNAs 25, 92a or 21 isolated from HUVEC between TNF-α group and control group, while microRNA 106b decreased in TNF-α group.

CONCLUSIONInflammation could induce endothelial cells to release angiogenesis associated microRNAs into circulation, causing higher levels of circulating endothelial cells derived microRNAs in atherosclerosis.

Annexin A5 ; metabolism ; Cell-Derived Microparticles ; metabolism ; Cells, Cultured ; Gene Expression Regulation ; drug effects ; Human Umbilical Vein Endothelial Cells ; drug effects ; metabolism ; Humans ; Inflammation ; genetics ; immunology ; MicroRNAs ; genetics ; metabolism ; Real-Time Polymerase Chain Reaction ; Tumor Necrosis Factor-alpha ; pharmacology

The preparation method, serum stability, efficiency of cellular uptake and apoptosis induction of the cell penetrating peptide TAT and cleavable PEG co-modified liposomes loaded with paclitaxel (C-TAT-Lipo) were investigated. The best preparation procedure was performed by orthogonal test based on single factor screening method. First, the paclitaxel (PTX)-loaded liposomes were prepared by filming-rehydration method, evaluated with entrapment efficiency and polydispersity index. The morphology of C-TAT-Lipo was characterized by transmission electron microscopy. Turbidity variations were monitored in the presence of fetal bovine serum (FBS) to evaluate the serum stability of the liposomes developed here. Next, the efficiency of cellular uptake of different Rho-PE-labeled liposomes on B16F1 cells in vitro was evaluated by confocal laser scanning microscopy (CLSM) and flow cytometry. The quantitative analysis of apoptosis induced by different PTX-loaded liposomes was performed by Annexin V-FITC/PI double staining. The optimal formulation was as follows: Chol : lipid: 1 : 8 (molar ratio); drug : lipid: 1 : 40 (mass ratio); lipid concentration: 3 mmol x L(-1); temperature of hydration: 25 degrees C. The mean size and polydispersity index of C-TAT-Lipo were about (97.97 +/- 3.68) nm and 0.196 +/- 0.037, the zeta potential was (-0.89 +/- 0.45) mV, the entrapment efficiency of paclitaxel was (90.16 +/- 1.53)%. The particle sizes did not exhibit significant variations in 50% FBS over 24 h at 37 degrees C. The efficiency of cellular uptake of the C-TAT-Lipo increased 1.40 fold following the cleavage of PEG. Apoptosis analysis showed 59.3% increase of the apoptosis and necrosis profile of C-TAT-Lipo after the detachment of PEG shells, which was markedly higher than that of N-TAT-LP with or without glutathione and SL, respectively. The results indicate that the C-TAT-Lipo is successfully prepared by filming-rehydration method and shows significant antitumor activities.
Animals ; Annexin A5 ; Apoptosis ; Cell Line, Tumor ; Cell-Penetrating Peptides ; pharmacology ; Fluorescein-5-isothiocyanate ; analogs & derivatives ; Liposomes ; chemistry ; Melanoma, Experimental ; Mice ; Microscopy, Confocal ; Paclitaxel ; pharmacology ; Particle Size ; Polyethylene Glycols ; chemistry

OBJECTIVETo determine the effect of berberine (Ber) on norepinephrine (NE)-induced apoptosis in neonatal rat cardiomyocytes.

METHODSThe cultured neonatal rat cardiomyocytes were treated with NE in the presence or absence of Ber. The activity of lactate dehydrogenase (LDH) in the culture medium was examined, and apoptosis of cardiomyocytes was assessed by Hoechst 33258, isothiocyanate (FITC)-conjugated annexin-V, and propidine iodide (PI) staining. In addition, the activities of caspases-2 and-3 were measured by a fluorescent assay kit. The level of secreted tumor necrosis factor α (TNF-α) and production of intracellular reactive oxygen species (ROS) were also determined.

RESULTSNE at a concentration of 50 μ mol/L induced an obvious increase in the activity of LDH in the culture medium (P<0.05), which was inhibited by coincubation with 0.5, 1.0, or 2.0 μ mol/L Ber (P<0.05). Ber also significantly attenuated NE-induced apoptosis in a dose-dependent manner (P<0.01). Moreover, Ber at a dose of 2 μ mol/L markedly decreased the ROS and TNF-α productions (P <0.05) and inhibited the activation of caspases-2 and -3 in cardiomyocytes exposed to NE (P<0.05)h.

CONCLUSIONThe present study suggested that Ber could reduce NE-induced apoptosis in neonatal rat cardiomyocytes through inhibiting the ROS-TNF-α-caspase signaling pathway.

Animals ; Animals, Newborn ; Annexin A5 ; metabolism ; Apoptosis ; drug effects ; Berberine ; pharmacology ; Caspase 2 ; metabolism ; Caspase 3 ; metabolism ; Caspases ; metabolism ; Cell Nucleus ; drug effects ; metabolism ; Cell Shape ; drug effects ; DNA ; metabolism ; Enzyme Activation ; drug effects ; Flow Cytometry ; Fluorescein-5-isothiocyanate ; metabolism ; Immunohistochemistry ; L-Lactate Dehydrogenase ; metabolism ; Myocytes, Cardiac ; drug effects ; enzymology ; pathology ; Norepinephrine ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species ; metabolism ; Signal Transduction ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo investigate the effects of endothelial microvesicles (EMVs) induced by calcium ionophore A23187 on H9c2 cardiomyocytes.

METHODSHuman umbilical vein endothelial cells (HUVECs) were treated with 10 micromol/L A23187 for 30 min. EMVs from HUVECs were isolated by ultracentrifugation from the conditioned culture medium. EMVs were characterized using 1 and 2 microm latex beads and anti-PE-CD144 antibody by flow cytometry. For functional research, EMVs at different concentrations were cocultured with H9c2 cardiomyocytes for 6 h. Cell viability of H9c2 cells and the activity of LDH leaked from H9c2 cells were tested by colorimetry. Moreover, apoptosis of H9c2 cells was observed through Hoechst 33258 staining and tested by FITC-Annexin V/PI double staining.

RESULTSEMVs were induced by A23187 on HUVECs, and isolated by ultracentrifugation. We identified the membrane vesicles (< 1 microm) induced by A23187 were CD144 positive. In addition, the EMVs could significantly reduce the viability of H9c2 cells, and increase LDH leakage from H9c2 cells in a dose dependent manner (P < 0.05). Condensed nuclei could be observed with the increasing concentrations of EMVs through Hoechst 33258 staining. Furthermore, increased apoptosis rates of H9c2 cells could be assessed through FITC-Annexin V/PI double staining by flow cytometry.

CONCLUSIONMicrovesicles could be released from HUVECs after induced by A23187 through calcium influx, and these EMVs exerted a pro-apoptotic effect on H9c2 cells by induction of apoptosis.

Annexin A5 ; Apoptosis ; Calcimycin ; pharmacology ; Calcium ; metabolism ; Cell Line ; Cell Membrane ; drug effects ; Coculture Techniques ; Flow Cytometry ; Fluorescein-5-isothiocyanate ; analogs & derivatives ; Human Umbilical Vein Endothelial Cells ; Humans ; Myocytes, Cardiac ; drug effects ; Staining and Labeling

OBJECTIVETo study the differentially expressed proteins in the process of annexin 5 stimulating testosterone secretion in cultured rat Leydig cells.

METHODSPrimary rat Leydig cells were cultured in vitro and treated with annexin 5 at the concentration of 1 nmol/L for 24 hours, and the cell proteins were extracted to be compared by two-dimensional gel electrophoresis (2-DE). The differentially expressed protein spots were selected to be analyzed by mass spectrometry.

RESULTSWe obtained electrophoresis profiles with high resolution and reproducibility, found 50 differentially expressed protein spots, and identified 36 by mass spectrometry, of which 23 were overexpressed and 13 underexpressed in the Leydig cells treated with annexin 5.

CONCLUSIONDifferentially expressed protein profiles were established in the process of annexin 5 stimulating testosterone secretion in cultured rat Leydig cells, and identified the key role of these proteins in testosterone secretion. Our findings might be helpful to illuminate the mechanism of annexin 5 regulating testosterone secretion in rat Leydig cells.

Animals ; Annexin A5 ; pharmacology ; Cells, Cultured ; Electrophoresis, Gel, Two-Dimensional ; Leydig Cells ; drug effects ; metabolism ; Male ; Mass Spectrometry ; Proteins ; metabolism ; Proteome ; analysis ; Rats ; Rats, Sprague-Dawley ; Testosterone ; secretion

OBJECTIVETo study luteolin-induced non-small cell lung cancer cell line A549 apoptosis and the molecular mechanism for inhibiting its cycle arrest (G2 stage).

METHODMTT assay showed that luteolin had obvious inhibitory effect on A549 and indicated the half inhibition ratio (IC50). Cell cycle and apoptosis were detected by Hoechst 33258 nuclear staining assay, Annexin V-FITC/PI double staining and flow cytometry. Western blotting assay revealed changes in cycle and apoptosis-related proteins induced by luteolin. Possible molecular mechanism was suggested by Western blotting and immunocytochemistry.

RESULTLuteolin had an obvious growth inhibitory effect on A549 cells, with IC50 of 45.2 micromol x L(-1) at 48 h. Flow cytometry showed A549 cells mainly arrested in G2 stage after being treated by luteolin, with low expressions in cyclin A, p-CDC2 and p-Rb. Hoechst 33258 nuclear staining and Annexin V-FITC/PI double staining showed that the luteolin treatment group showed a significant apoptosis rate than the non-treatment group. Western blotting found luteolin can increase phosphorylation of JNK and decrease that of NF-kappaKB (p65). Immunocytochemistry results revealed luteolin can inhibit TNF-alpha-stimulated p65 from nuclear translocation as a transcription factor and thus promoting cell apoptosis.

CONCLUSIONLuteolin can obviously induce apoptosis of human non-small cell lung cancer cell A549 possibly by increasing phosphorylation of JNK to activate mitochondria apoptosis pathway, while inhibiting NF-kappaB from nuclear translocation as a transcription factor.

Annexin A5 ; metabolism ; Apoptosis ; drug effects ; Blotting, Western ; Carcinoma, Non-Small-Cell Lung ; metabolism ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Humans ; Luteolin ; pharmacology ; NF-kappa B ; metabolism

OBJECTIVETo investigate the role of Annexin 5 in protecting human sperm membrane and DNA integrity.

METHODSWe collected 53 semen samples based on the criteria of sperm density > 20 x 10(6)/ml and motility > 60%, and divided them into an experimental group (2.5 microl 10(-6) mol/L Annexin 5 added to 47.5 microl semen), a negative control group (2.5 microl 1 mol/L Tris-HCl [pH 8.0, 25 degrees C] added to 47.5 microl semen), and a blank control group (2.5 microl 0.01 mol/L PBS [pH 7.4] added to 47.5 microl semen). After 20 minutes of incubation, we evaluated the sperm membrane integrity using the hypoosmotic swelling test and, after another 60 minutes of treatment with H2O2 at 2.5 microl 10.02 mol/L, measured the sperm nuclear DNA integrity by acridine orange fluorescent staining.

RESULTSAfter 20 minutes of treatment with Annexin 5, the experimental group showed extremely significant difference in the percentage of hypoosmotic swelling sperm ([66.17 +/- 12.02] %) from the blank control ([58.13 +/- 13.08]%, P < 0.01) and the negative control group ([59.94 +/- 11.91]%, P < 0.01), but there was no significant difference between the latter two. Treatment with H2O2 remarkably increased DFI in the experimental group (6.39 +/- 1.07) as compared with the blank control (11.16 +/- 1.16) and the negative control group (10.86 +/- 1.05, P < 0.01), but no significant difference was observed between the latter two.

CONCLUSIONAnnexin 5 can increase the percentage of hypoosmotic swelling sperm in vitro and protect sperm membrane integrity, and it can also protect sperm DNA from H2O2 damage.

Annexin A5 ; pharmacology ; Cell Membrane ; drug effects ; DNA ; DNA Fragmentation ; Humans ; Male ; Sperm Count ; Sperm Motility ; Spermatozoa ; drug effects

OBJECTIVEGonadotropin releasing hormones (GnRH) regulate the expression of annexin 5 in Leydig cells, and annexin 5 is supposed to be a signal molecule in regulating testosterone secretion. This study aimed to investigate the function of annexin 5 in male reproduction by observing its effect on human sperm motility in vitro.

METHODSThe encoding sequence of rat annexin 5 was chemically synthesized and inserted into the HIS fusion expression vector pET28a. The expression of the fusion protein HIS-annexin 5 was induced by isopropyl-beta-D-thiogalactoside (IPTG) under the control of the T7 promoter, and the products were purified by affinity chromatography. The anticoagulant activity of annexin 5 was determined by the modified activated partial thromboplastin time (APTT) test. Semen samples from 15 donors were assigned to a control and an annexin 5 group, the latter treated with recombinant annexin 5 at the concentration of 10(-8) mol/L. Sperm motility and the percentage of grade a + b sperm were measured by computer-assisted semen analysis (CASA) after 20 and 60 min exposure, and the sperm ascending experiment was done after 20 min treatment.

RESULTSThe product of the synthesized target gene was 947 bp in length, and the inserted sequence corresponded to the published encoding sequence of rat annexin 5. The plasmid pET28a-annexin 5 was transformed into E. coli BL21(DE3) and IPTG induced a fusion protein with a relative molecular weight of about 36,000, a purity of 95% and a high anticoagulant activity. Compared with the control group, sperm motility and the percentage of grade a + b sperm were increased by 40% (P < 0.01) and 21% (P < 0.01), respectively, after 20 min treatment with annexin 5, but neither showed any significant improvement after 60 min. The sperm ascending altitude was remarkably elevated after annexin 5 treatment, with extremely significant difference from the control group (37.84 +/- 6.35 vs. 49.5 +/- 12.27, P < 0.01).

CONCLUSIONAn annexin 5 recombinant expression vector was successfully constructed. The protein annexin 5 can be efficiently expressed in E. coli and effectively improve human sperm motility in vitro.

Animals ; Annexin A5 ; genetics ; pharmacology ; Genetic Vectors ; Humans ; Male ; Plasmids ; Rats ; Recombinant Fusion Proteins ; genetics ; pharmacology ; Sperm Motility

BACKGROUNDThe side effects of cyclosporine therapy include thromboembolic complications. However, the mechanisms underlying the hypercoagulable state induced by cyclosporine are not fully understood. Cyclosporine binds to red blood cells (RBCs) with a high affinity in circulation and alters the membranes of RBCs. Therefore, we propose that such alterations in RBCs membranes play a role in cyclosporine-induced coagulopathy and this disorder may be rectified by lactadherin, a phosphatidylserine binding protein.

METHODSRBCs from healthy adults were treated with various concentrations of cyclosporine. Procoagulant activity of the RBC membrane was measured by the single stage recalcification time and confirmed by detection of tenase and thrombin assembly through enzymatic assays. Inhibition assays of coagulation were carried out in the presence of lactadherin, annexin V or antitissue factor. Phosphatidylserine exposure was detected by flow cytometry and confocal microscopy through binding with fluorescein isothiocyanate (FITC)-labeled lactadherin as well as FITC annexin V.

RESULTSRBCs treated with cyclosporine demonstrated increased procoagulant activity. Cyclosporine treatment markedly shortened the clotting time of RBCs ((305 +/- 10) seconds vs (366 +/- 15) seconds) and increased the generation of intrinsic factor Xase ((7.68 +/- 0.99) nmol/L vs (2.86 +/- 0.11) nmol/L) and thrombin ((15.83 +/- 1.37) nmol/L vs (4.88 +/- 0.13) nmol/L). Flow cytometry and confocal microscopy indicated that cyclosporine treatment induced an increased expression of phosphatidylserine on the RBC membrane. Lactadherin was more sensitive in detecting phosphatidylserine exposure of the RBC membrane than annexin V. The modulating effect of procoagulant activity was concomitant with and dependent on phosphatidylserine exposure. Blocking of phosphatidylserine with lactadherin effectively inhibited over 90% of FXa generation and prothrombinase activity and prolonged coagulation time.

CONCLUSIONSProcoagulant properties of RBCs membranes resulting from phosphatidylserine exposure may play an important role in cyclosporine-induced thrombosis. Lactadherin can be used as a sensitive probe for phosphatidylserine detection. Its high affinity for phosphatidylserine may provide a new approach for the treatment of cyclosporine induced thrombogenic properties.

Adult ; Animals ; Annexin A5 ; chemistry ; Cattle ; Cell Membrane ; drug effects ; metabolism ; Cells, Cultured ; Cyclosporine ; pharmacology ; Erythrocytes ; drug effects ; metabolism ; Flow Cytometry ; Humans ; Membrane Glycoproteins ; chemistry ; Microscopy, Confocal ; Milk Proteins ; chemistry ; Phosphatidylserines ; chemistry ; metabolism ; Thrombosis ; chemically induced ; metabolism