To investigate the effect of apigenin on self-renewal for sphere-forming cells in human small cell lung cancer cell line NCI-H446 and the underlying mechanisms.
 Methods: Sphere-forming cells from NCI-H446 cell line were cultured in stem cell-conditioned culture medium with ultra-low attachment surface plates. The rate of sphere-forming cells in the second passage sphere-forming cells was used to evaluate the inhibitory effects of apigenin on the self-renewal for sphere-forming cells. The protein level of urokinase-type plasminogen activator receptor (uPAR) in spheroids was analyzed by Western blot.
 Results: Apigenin signifcantly inhibited the self-renewal of the second passage sphere-forming cells [0, 5.0, 10.0, 20.0 μmol/L apigenin: (18.2±1.9)%, (13.6±1.7)%, (10.6±1.6)%, (6.9±1.3)%, respectively] and down-regulated uPAR expression in a concentration-dependent manner (P<0.05).
 Conclusion: Apigenin inhibits the self-renewal capacity of sphere-forming cells in NCI-H446 cells, which may be associated with down-regulation of uPAR expression.
Apigenin ; pharmacology ; Cell Line, Tumor ; Down-Regulation ; drug effects ; genetics ; Humans ; Lung Neoplasms ; Neoplastic Stem Cells ; drug effects ; pathology ; physiology ; Receptors, Cell Surface ; Receptors, Urokinase Plasminogen Activator ; drug effects ; genetics ; metabolism ; Signal Transduction ; Small Cell Lung Carcinoma ; drug therapy ; pathology ; Spheroids, Cellular ; drug effects ; physiology ; Stem Cells

BACKGROUNDStent thrombosis is one of severe complications after sirolimus-eluting stent implantation. Rapamycin (sirolimus) promotes arterial thrombosis in in vivo studies. However, the underlying molecular and transcriptional mechanisms of this adverse effect have not been thoroughly investigated. This study was designed to examine the effects of rapamycin on the expression of the gene, Kruppel-like factor 2 (KLF2), and its transcriptional targets in mice.

METHODSMice were randomly divided into four groups: the control group (intraperitoneal injection with 2.5% of dimethyl sulfoxide (DMSO) only), rapamycin group (intraperitoneal injection with 2 mg/kg of rapamycin only), Ad-LacZ + rapamycin group (carotid arterial incubation with Ad-LacZ plus intraperitoneal injection with 2 mg/kg of rapamycin 10 days later), and Ad-KLF2 + rapamycin group (carotid arterial incubation with Ad-KLF2 plus intraperitoneal injection with 2 mg/kg rapamycin 10 days later). The carotid arterial thrombosis formation was induced by FeCl3 and the time of arterial thrombosis was determined. Finally, the RNA and protein of carotid arteries were extracted for KLF2, tissue factor (TF), plasminogen activator inhibitor-1 (PAI-1), endothelial nitric oxide synthase (eNOS), thrombomodulin (TM) mRNA and protein analysis.

RESULTSCompared with controls, treatment with rapamycin inhibited KLF2, eNOS and TM mRNA and protein expression, and enhanced TF and PAI-1 mRNA and protein expression, and shortened time to thrombotic occlusion from (1282 ± 347) seconds to (715 ± 120) seconds (P < 0.01) in vivo. Overexpression of KLF2 strongly reversed rapamycin-induced effects on KLF2, eNOS, TM, TF and PAI-1 expression. KLF2 overexpression increased the time to thrombotic occlusion to control levels in vivo.

CONCLUSIONSRapamycin induced an inhibition of KLF2 expression and an imbalance of anti- and pro-thrombotic gene expression, which promoted arterial thrombosis in vivo. Overexpression of KLF2 increased KLF2 expression and reversed time to thrombosis in vivo.

Animals ; Carotid Arteries ; metabolism ; Drug-Eluting Stents ; adverse effects ; Kruppel-Like Transcription Factors ; analysis ; genetics ; physiology ; Mice ; Mice, Inbred C57BL ; Nitric Oxide Synthase Type III ; physiology ; Plasminogen Activator Inhibitor 1 ; physiology ; Sirolimus ; pharmacology ; Thrombomodulin ; physiology ; Thrombosis ; chemically induced

Tumor cells are known to produce larger amounts of reactive oxygen species (ROS) than normal cells. Although numerous reports have indicated the importance of ROS in urokinase plasminogen activator (uPA) production, the precise mechanisms remain controversial. In our study, we investigated the effect of ROS on uPA generation in human hepatoma cells, HepG2 and Hep 3B. We determined the effects of hepatocyte growth factor (HGF) on the regulation of ROS, which resulted in suppression of ROS production, as measured with the fluorescent probe, 2'-7'-dichlorofluorescein diacetate. The role of HGF in modulating ROS production, particularly that regulated by Rac-1, was determined. HGF suppressed the increment in Rac-1-regulated ROS in both cell lines. Treatment with 200 microM of H2O2 showed a 1.6-2.1 fold increment in HGF, but a little increment occurred at 500 microM of H2O2. It looks no dose dependent manner. Combined treatment with H2O2 and HGF, resulted in a slightly increased production of HGF compared to no treatment (control). Also, H2O2 upregulated uPA expression in both hepatoma cell lines. To identify the downstream pathways regulated by ROS, we treated cells with PD 98059, an MEK inhibitor, and SB 203580, a p38 inhibitor, after treatment with H2O2, and showed negative control between ERK and p38 kinase activities for uPA regulation. We found that HGF modulate Rac-1-regulated ROS production through activation of Akt and ROS regulates uPA production via MAP kinase, which provides a novel clue to clarify the mechanism underlying hepatoma progression.
Cell Line, Tumor ; Fluorescent Dyes/chemistry ; Hepatocyte Growth Factor/pharmacology/*physiology ; Humans ; Hydrogen Peroxide/pharmacology ; Imidazoles/pharmacology ; Liver Neoplasms/drug therapy ; Mitogen-Activated Protein Kinases/antagonists & inhibitors/*metabolism ; Pyridines/pharmacology ; Reactive Oxygen Species/*metabolism ; Recombinant Proteins/pharmacology ; Urokinase-Type Plasminogen Activator/*biosynthesis ; rac1 GTP-Binding Protein/metabolism

OBJECTIVETo investigate the role of integrin-linked kinase (ILK) on renal tubular epithelial-mesenchymal transition and the regulatory effect of urokinase on LIK expression in mice with obstructive nephropathy.

METHODSNormal male mice were randomly divided into sham-operated group (n=20), unilateral ureteral obstruction (UUO) group (n=28), and UUO with urokinase treatment group (uPA, n=28), and UUO was induced surgically in the latter two groups. The mice were sacrificed on days l, 3, 7 and 14 after the surgery, and renal interstitial fibrosis (RIF) was graded according to the result of Masson staining. The expression of ILK in the renal tissues of the rats was examined by immunofluorescence staining and Western blotting, and the expression of E-cadherin was detected by immunohistochemistry. RT-PCR was used to examine the mRNA expressions of ILK, E-cadherin and alpha-smooth muscle actin (alpha-SMA).

RESULTSThe expressions of ILK mRNA and protein were significantly increased in UUO group, but significantly decreased by treatment with uPA (P<0.05). The expression of alpha-SMA mRNA level was significantly increased, while E-cadherin decreased in mice with UUO on day 3 after the surgery. Treatment with uPA significantly inhibited such effects (P<0.05).

CONCLUSIONILK plays an important role in renal interstitial fibrosis by mediating epithelial-mesenchymal transition. Urokinase attenuates renal tubulointerstitial fibrosis in mice with UUO possibly by inhibiting ILK expression and preventing tubular epithelial-mesenchymal transition.

Animals ; Cell Transdifferentiation ; drug effects ; Epithelial Cells ; metabolism ; pathology ; Fibrosis ; Kidney Tubules ; metabolism ; pathology ; Male ; Mesoderm ; pathology ; Mice ; Protein-Serine-Threonine Kinases ; genetics ; metabolism ; physiology ; Ureteral Obstruction ; genetics ; metabolism ; pathology ; Urokinase-Type Plasminogen Activator ; pharmacology

OBJECTIVETo study the mechanism of uPA improving sperm capacitation by investigating the effect of uPA on the mitochondrial function of mouse capacitated-sperm in vitro.

METHODSMitochondrial function of mouse capacitated-spermatozoa was evaluated through the assessment of mitochondrial membrane potential using JC-1 performed by flow cytometer and fluorescent microscope respectively. The experiment and the control groups were designed according to the presence or absence of uPA, each divided into 5 subgroups based on the different time of uPA treatment (or BWW in the control groups) at 0, 5, 15, 30 and 60 min respectively.

RESULTS(1) Compared with that at 0 min, the mean fluorescence intensity of JC-1 within the spermatozoal body and the percentage of orange-red colored spermatozoa in the experiment group were increased significantly at 5 and 15 min respectively after uPA incubation (P < 0.05). (2) The mean fluorescence intensity of JC-1 within the spermatozoal body at 15, 30 and 60 min and the percentage of orange-red colored spermatozoa at 5 and 15 min in the group were significantly higher than those in the control group (P < 0.05).

CONCLUSIONuPA could increase the mitochondrial membrane potential of mouse capacitated-spermatozoa in vitro, and maintain it at a high level for a certain period of time. By enhancing sperm mitochondrial function, uPA may provide sufficient energy for capacitated-spermatozoa to increase their motility and change their motor pattern, which might be one of the therapeutic mechanisms of uPA on male infertility.

Animals ; Flow Cytometry ; Fluorescent Dyes ; Male ; Membrane Potential, Mitochondrial ; drug effects ; Mice ; Mice, Inbred Strains ; Sperm Capacitation ; Sperm Motility ; Spermatozoa ; drug effects ; physiology ; Urokinase-Type Plasminogen Activator ; pharmacology

OBJECTIVETo study the effects of the urokinase-type plasminogen activator (uPA) on the chemotactic responses of spermatozoa in vitro, and to explore the possible action mechanisms of uPA for male infertility.

METHODSThe chemotactic responses of spermatozoa were measured using spermatozoal accumulation in the capillary. According to the gradient directions of chemoattractant concentrations in the capillary, the recruits were divided into three groups: Group A (the ascending gradient of chemoattractant), Group B (the descending gradient of chemoattractant) and Group C (control). The chemoattractant in the capillary and the treating fluid in spermatozoal wells of Group A were uPA of different concentrations and Hamś F-10, respectively, while those of Group B were just opposite to Group A, and those of Group C were both Hamś F-10. Then the sperm densities in different capillaries were measured at different points of time.

RESULTS(1) Spermatozoa moved chemotactically following the concentrations of uPA. The accumulative action of spermatozoa in Group A was obviously stronger than in Groups B and C (P < 0.05 ). (2) The effects of 20 IU/ml uPA on the chemotactic responses of spermatozoa were most significant. (3) The sperm densities in the three groups increased with time, significantly different at 20 min and 30 min (P < 0.05). (4) uPA could increase sperm motility and promote sperm movement, as well as induce sperm chemotactic responses.

CONCLUSIONuPA could induce sperm chemotactic responses and increase sperm motility, which is presumably one of the action mechanisms of uPA on male infertility.

Animals ; Cells, Cultured ; Chemotaxis ; drug effects ; Dose-Response Relationship, Drug ; Male ; Rats ; Rats, Wistar ; Sperm Motility ; drug effects ; Spermatozoa ; drug effects ; physiology ; Urokinase-Type Plasminogen Activator ; pharmacology

OBJECTIVETo investigate the effect of cilazapril on endothelial cell function and fibrinolysis system in the canine atrial fibrillation (AF) models.

METHODSAll canines were divided into three groups: (1) Control group, without atrial pacing; (2) Atrial pacing group, in which atrial fibrillation was established by rapid atrial pacing at 400 bpm for 6 weeks; (3) Atrial pacing together with cilazapril group, in which cilazapril was given before and after atrial pacing. Nitric oxide (NO) of atrial endocardium was measured with NO-specific microelectrode. The expression of plasminogen activator inhibitor-1 (PAI-1) and tissue-type plasminogen activator (tPA) protein in atrium was determined by Western Blot analysis and immunohistochemical staining. Plasma levels of von Willebrand Factor (vWF), PAI-1 and tPA were analyzed by enzyme-linked immunoadsorbent assay.

RESULTSNO production from atrial endocardium was significantly increased in atrial pacing together with cilazapril group than atrial pacing group [(42.6 +/- 9.9) nmol/L vs (23.4 +/- 5.8) nmol/L, P < 0.05], whereas the plasma levels of vWF were decreased [(75.4 +/- 12.8)% vs (125.9 +/- 20.6)%, P < 0.05]. Compared to controls, the expression of atrium tPA protein in atrial pacing together with cilazapril group was significantly upregulated (4052 +/- 857 vs 1936 +/- 421, P < 0.05) and PAI-1 protein was downregulated (2487 +/- 542 vs 3164 +/- 827, P < 0.05). Cilazapril also significantly increased tPA antigen and decreased PAI-1 antigen in plasma.

CONCLUSIONCilazapril can favorably improve endothelial function and resume the balance of fibrinolysis system in AF, which might be of beneficial to hypercoagulated state in AF.

Angiotensin-Converting Enzyme Inhibitors ; pharmacology ; Animals ; Atrial Fibrillation ; blood ; drug therapy ; physiopathology ; Cilazapril ; pharmacology ; Disease Models, Animal ; Dogs ; Endothelial Cells ; drug effects ; physiology ; Female ; Fibrinolysis ; drug effects ; Immunohistochemistry ; Male ; Plasminogen Activator Inhibitor 1 ; analysis ; Tissue Plasminogen Activator ; analysis

Angiotensin-Converting Enzyme Inhibitors ; pharmacology ; Animals ; Atrial Fibrillation ; blood ; drug therapy ; physiopathology ; Cilazapril ; pharmacology ; Dogs ; Echocardiography ; Endothelial Cells ; drug effects ; physiology ; Fibrinolysis ; drug effects ; Nitric Oxide ; biosynthesis ; Plasminogen Activator Inhibitor 1 ; analysis ; Tissue Plasminogen Activator ; analysis

BACKGROUNDConnective tissue growth factor (CTGF) contributes greatly to renal tubulointerstitial fibrosis, which is the final event leading to end-stage renal failure. This study was designed to investigate the effects of CTGF antisense oligodeoxynucleotides (ODNs) on the expressions of plasminogen activator inhibitor-1 (PAI-1) and fibronectin in renal tubular cells induced by transforming growth factor beta1 (TGF-beta1) in addition to the role of CTGF in the accumulation and degradation of renal extracellular matrix (ECM).

METHODSA human proximal tubular epithelial cell line (HKC) was cultured in vitro. Cationic lipid-mediated CTGF antisense ODNs were transfected into HKC cells. After HKC cells were stimulated with TGF-beta1 (5 microg/L), the mRNA levels of PAI-1 and fibronectin were measured by RT-PCR. Intracellular PAI-1 protein synthesis was assessed by flow cytometry. The secreted PAI-1 and fibronectin in the medium were determined by Western blot and ELISA, respectively.

RESULTSTGF-beta1 was found to induce tubular CTGF, PAI-1, and fibronectin mRNA expression. PAI-1 and fibronectin mRNA expression induced by TGF-beta1 was significantly inhibited by CTGF antisense ODNs. CTGF antisense ODNs also inhibited intracellular PAI-1 protein synthesis and lowered the levels of PAI-1 and fibronectin protein secreted into the medium.

CONCLUSIONSCTGF may play a crucial role in the accumulation and degradation of excessive ECM during tubulointerstitial fibrosis, and transfecting CTGF antisense ODNs may be an effective way to prevent renal fibrosis.

Cells, Cultured ; Connective Tissue Growth Factor ; Extracellular Matrix ; metabolism ; Fibronectins ; genetics ; secretion ; Humans ; Immediate-Early Proteins ; genetics ; physiology ; Intercellular Signaling Peptides and Proteins ; genetics ; physiology ; Kidney Tubules ; metabolism ; Oligonucleotides, Antisense ; pharmacology ; Plasminogen Activator Inhibitor 1 ; genetics ; secretion ; RNA, Messenger ; analysis ; Transfection ; Transforming Growth Factor beta ; pharmacology ; Transforming Growth Factor beta1

In the injured brain, microglia is known to be activated and produce proinflammatory mediators such as interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha) and inducible nitric oxide synthase (iNOS). We investigated the role of protein kinase A (PKA) in microglial activation by both plasminogen and gangliosides in rat primary microglia and in the BV2 immortalized murine microglial cell line. Both plasminogen and gangliosides induced IL-1beta, TNF-alpha and iNOS mRNA expression, and that this expression was inhibited by the addition of the PKA inhibitors, KT5720 and H89. Both plasminogen and gangliosides activated PKA and increased the DNA binding activity of the cAMP response element- binding protein (CREB). Furthermore, KT5720 and H89 reduced the DNA binding activities of CREB and NF-kappaB in plasminogen-treated cells. These results suggest that PKA plays an important role in plasminogen and gangliosides- induced microglial activation.
Animals ; Carbazoles/pharmacology ; Cell Line ; Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors/*physiology ; DNA-Binding Protein, Cyclic AMP-Responsive/metabolism ; DNA-Binding Proteins/metabolism ; Gangliosides/pharmacology/*physiology ; Gene Expression Regulation ; Indoles/pharmacology ; Interleukin-1/genetics ; Isoquinolines/pharmacology ; Mice ; Microglia/drug effects/*enzymology/*immunology ; NF-kappa B/metabolism ; Nitric-Oxide Synthase/genetics ; Plasminogen/pharmacology/*physiology ; Pyrroles/pharmacology ; RNA, Messenger/analysis/metabolism ; Rats ; Research Support, Non-U.S. Gov't ; Sulfonamides/pharmacology ; Tumor Necrosis Factor-alpha/genetics