OBJECTIVETo study the role of sirtuin 1 (SIRT1) in Fas ligand (FasL) expression regulation during vascular lesion formation and to elucidate the potential mechanisms.

METHODSSIRT1 and FasL protein levels were detected by Western blotting in either mouse arteries extract or the whole rat aortic vascular smooth muscle cell (VSMC) lysate. Smooth muscle cell (SMC)-specific human SIRT1 transgenic (Tg) C57BL/6 mice and their littermate wild-type (WT) controls underwent complete carotid artery ligation (ligation groups) or the ligation-excluded operation (sham groups). The carotid arteries were collected 1 day after operation. Reverse transcription-polymerase chain reaction was performed to detect the mRNA levels of SIRT1 and FasL. Luciferase reporter assays were performed to detect the effect of WT-SIRT1, a dominant-negative form of SIRT1 (SIRT1H363Y), and GATA-6 on the promoter activity of FasL. Flow cytometry assay was applied to measure the hypodiploid DNA content of VSMC so as to monitor cellular apoptosis.

RESULTSSIRT1 was expressed in both rat aortic VSMCs and mouse arteries. Forced SIRT1 expression increased FasL expression both in injured mouse carotid arteries 1 day after ligation (P<0.001) and VSMCs treated with serum (P<0.05 at the transcriptional level, P<0.001 at the protein level). No notable apoptosis was observed. Furthermore, transcription factor GATA-6 increased the promoter activity of FasL (P<0.001). The induction of FasL promoter activity by GATA-6 was enhanced by WT-SIRT1 (P<0.001), while SIRT1H363Y significantly relieved the enhancing effect of WT-SIRT1 on GATA-6 (P<0.001).

CONCLUSIONSOverexpression of SIRT1 up-regulates FasL expression in both flow-restricted mouse carotid arteries and serum-stimulated VSMCs. The transcription factor GATA-6 participates in the transcriptional regulation of FasL expression by SIRT1.

Animals ; Apoptosis ; Carotid Arteries ; physiology ; Fas Ligand Protein ; genetics ; GATA6 Transcription Factor ; physiology ; Male ; Muscle, Smooth, Vascular ; cytology ; metabolism ; Myocytes, Smooth Muscle ; metabolism ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Sirtuin 1 ; physiology ; Up-Regulation

OBJECTIVETo investigate apoptosis of tumor infiltrating dendritic cells (TIDC) and their expression of Fas/FasL (CD95/CD95L) in human endometrioid adenocarcinoma.

METHODSThe apoptotic rate of TIDC was measured in 45 cases of endometrioid adenocarcinoma and 20 cases of normal endometrium tissues (control) by double-label immunohistochemistry using the monoclonal antibody S-100 protein and TUNEL technique. The expressions of Fas and FasL in TIDCs were detected using double-label immunohistochemistry and imaging analysis.

RESULTSThe apoptotic rate of TIDCs in endometrioid adenocarcinoma were significantly higher than that in normal endormetrium [(13.02∓0.64)% vs (6.82∓0.53)%, P<0.05]. The expression levels of Fas in the TIDCs were significantly lower, whereas FasL expression significantly higher in endometrioid adenocarcinoma than in normal endormetrium (7.88∓1.05 vs 19.25∓3.03, P<0.05; 12.95∓2.25 vs 7.51∓1.14, P<0.05).

CONCLUSIONIncreased apoptosis of the TIDCs and abnormal expression of Fas/FasL in TIDCs in endometrioid adenocarcinoma may lead to tumor immune escape.

Apoptosis ; physiology ; Carcinoma, Endometrioid ; immunology ; metabolism ; pathology ; Case-Control Studies ; Dendritic Cells ; immunology ; Endometrial Neoplasms ; immunology ; metabolism ; pathology ; Fas Ligand Protein ; genetics ; metabolism ; Female ; Humans ; Lymphocytes, Tumor-Infiltrating ; immunology ; Tumor Escape ; fas Receptor ; genetics ; metabolism

OBJECTIVETo investigate the mechanism of immune hyporesponsiveness induced by donor-antigen- unloaded recipient-derived immature dendritic cell (imDC) of liver grafts in rats.

METHODSForty Sprague-Dawley rats (donor) and forty male Wistar rats (recipient) were randomly divided into 4 groups: control, cyclosporine A (CsA), mature DC (mDC), and imDC groups respectively, with 10 donor rats and 10 recipient rats in each group. Recipient rats in CsA group were treated with 10 mg•kg⁻¹•d⁻¹ CsA starting day 2 after the transplantation. Recipients in the mDC or imDC groups were given Wistar rat derived mDCs (1 × 10⁶/rat) or imDCs (1 × 10⁶/rat) via dorsal vein of the penis respectively 1 day before the transplantation. In each group, 5 recipients were kept for determination of survival time and the other 5 rats were executed at day 10 after transplantation. Blood samples were collected for the measurement of serum alanine aminotransferase (ALT), total bilirubin (TBIL), interleukin 2 (IL-2), interferon gamma (IFN-γ), IL-4, and IL-10 levels. Liver tissue was harvested for HE staining and acute rejection evaluation. Expression levels of Fas-L/Fas in the grafts were detected by immunohistochemical staining; and Western blot was used to detect the expression level of Scurfin.

RESULTSThe survival time of CsA and imDC groups was significantly longer than that of control and mDC groups (all P < 0.05). The levels of serum ALT and TBIL in the control group (2072.20 ± 217.93 IU/L and 147.42 ± 22.02 µmol/L) and mDC group (2117.00 ± 285.13 IU/L and 141.58 ± 20.82 µmol/L) were significantly higher than those in the CsA group (59.68 ± 13.48 IU/L and 15.40 ± 2.13 µmol/L) or imDC group (50.80 ± 9.63 IU/L and 14.44 ± 3.49 µmol/L) (all P < 0.05). In the CsA and imDC groups, the levels of IL-2 (22.52 ± 3.75 pg/mL and 22.12 ± 3.90 pg/mL) and IFN-γ (309.20 ± 25.19 pg/mL and 321.00 ± 21.64 pg/mL) were significantly lower, but the levels of IL-4 (297.60 ± 25.07 pg/mL and 277.00 ± 22.47 pg/mL) and IL-10 (1226.00 ± 140.49 pg/mL and 1423.00 ± 106.39 pg/mL) were higher than those of the control (IL-2: 147.78 ± 12.80 pg/mL, IFN-γ: 1758.60 ± 106.22 pg/mL, IL-4: 17.40 ± 4.77 pg/mL, IL-10: 81.00 ± 9.47 pg/mL) and mDC groups (IL-2: 142.34 ± 9.29 pg/mL, IFN-γ: 1835.00 ± 82.63 pg/mL, IL-4: 15.60 ± 3.96 pg/mL, IL-10: 68.80 ± 11.23 pg/mL) (all P < 0.01). The expression level of Scurfin protein on CD4+ CD25+ T cells of the imDC group (1.34 ± 0.29) was significantly higher than that in the control (0.72 ± 0.13), CsA (0.37 ± 0.11), and mDC groups (0.78 ± 0.17) (all P < 0.05).

CONCLUSIONDonor-antigen-unloaded recipient-derived imDC is an effective treatment in inducing immune hyporesponsiveness through induction of T cell apoptosis, shift in Thl/Th2 balance, and proliferation of regulatory T cell.

Animals ; Antigens ; immunology ; Cytokines ; immunology ; Dendritic Cells ; cytology ; immunology ; transplantation ; Fas Ligand Protein ; immunology ; Forkhead Transcription Factors ; metabolism ; Graft Rejection ; immunology ; Graft Survival ; immunology ; Humans ; Immunity ; physiology ; Liver ; cytology ; immunology ; pathology ; Liver Transplantation ; immunology ; Male ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Rats, Wistar ; fas Receptor ; immunology

Antineoplastic Agents ; therapeutic use ; Apoptosis ; drug effects ; Caspases ; metabolism ; physiology ; Enzyme Activation ; Fas Ligand Protein ; metabolism ; Humans ; NF-kappa B ; metabolism ; Neoplasms ; metabolism ; therapy ; Neovascularization, Pathologic ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Signal Transduction

The changes of pressure in local circulation flow field and the alterations of biorheological characteristics in Endothelial cells (ECs) would follow the geometric changes of cardiovascular wall structures and would further result in distinct pathophysiological changes of endothelial cellular proliferation and vitality. This experiment is designed to observe the effects of pressure shift on ECs proliferation, apoptosis, and expression of apoptosis-associated protein, to elucidate the influences of pressure shift on the vitality of ECs, and to shed light on the dose-effect relationship concerned. By adopting flow cytometery, transmission electron microscopy, real-time RT-PCR and Western blotting, we set the levels of pressure loading ECs groups and set down the non-activated cultured ECs,single shear stress loading ECs as the control group for studies on the ultra-structure alterations, on the distribution of cell cycle and the changes of proliferation and apoptosis in ECs. We also investigated the changes of the expression of Caspase-3 gene and the changing regularity of P53, Bcl-2 and Fas protein at the translation level. When ECs being exposed to decreased pressure shift (-40 cmH2O), distinct apoptosis in ECs could be observed and a pattern of duration-dependence was seen. The expressions of P53, Bcl-2 and Fas proteins are essential for regulating the genesis and process of ECs apoptosis induced by -40 cmH2O pressure.
Apoptosis ; physiology ; Apoptosis Inducing Factor ; metabolism ; Caspase 3 ; metabolism ; Cell Proliferation ; Cells, Cultured ; Endothelial Cells ; cytology ; Fas Ligand Protein ; metabolism ; Humans ; Pressure ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rheology ; Stress, Mechanical ; Tumor Suppressor Protein p53 ; metabolism ; Umbilical Veins ; cytology

OBJECTIVETo determine the involvement of FasL/Fas pathway in apoptosis of J774A.1 cells induced by Leptospira interrogans.

METHODSThe cell infection model was established with mouse monocyte-macrophage J774A.1 cells infected by L.interrogans serogroup Icterohaemorrhagiae serovar lai strain 56601. The morphological characteristics of apoptotic J774A.1 cells were observed by DAPI staining method, and the apoptosis rate was quantitatively determined by flow cytometry. FasL neutralizing antibody was applied to block the apoptosis. Expression of FasL or Fas in the L.interrogans strain 56601-infected J774A.1 cells was detected by flow cytometry using PE-conjugated monoclonal antibody.

RESULTChromatin condensation and marginalization were found in J774A.1 cells infected by L.interrogans strain 56601 for 4 h, which became more predominant for 24 h and karyorrhexis was present in some cells. When J774A.1 cells were infected for 4 h and 24 h, the apoptosis rates were 53.6% and 64.31%, respectively. However, the apoptosis rates were decreased to 10.27% and 15.9% after the cells were pre-treated with FasL neutralizing antibody. When J774A.1 cells were infected for 4 h and 24 h, FasL expression rates were increased to 21.69% and 65.70% from that of 4.19% before infection, and Fas expression rates were risen to 91.96% and 88.01% from that of 12.88% before infection.

CONCLUSIONInducement of cell apoptosis is an important mechanism of L.interrogans strain 56601 injuring J774A.1 cells. The strain of L.interrogans is able to up-regulate FasL/Fas expression levels of host cells and induce apoptosis of the cells via FasL/Fas pathway.

Animals ; Apoptosis ; physiology ; Cell Line ; Fas Ligand Protein ; metabolism ; Leptospira interrogans ; pathogenicity ; Macrophages ; microbiology ; pathology ; Mice ; Up-Regulation ; fas Receptor ; metabolism

Although N-myc downstream regulated gene 2 (NDRG2) has been known to be a tumor suppressor gene, the function of this gene has not been elucidated. In the present study, we investigated the expression and function of NDRG2 in human gastric cancer. Among seven gastric cancer and two non-cancer cell lines, only two gastric cancer cell lines, SNU-16 and SNU-620, expressed NDRG2, which was detected in the cytoplasm. Interestingly, NDRG2 was highly expressed in normal gastric tissues, but gastric cancer patients were divided into NDRG2-positive and -negative groups. The survival rate of NDRG2-negative patients was lower than that of NDRG2-positive patients. We confirmed that the loss of NDRG2 expression was a significant and independent prognostic indicator in gastric carcinomas by multivariate analysis. To investigate the role of NDRG2 in gastric cancer cells, we generated a NDRG2-silenced gastric cancer cell line, which stably expresses NDRG2 siRNA. NDRG2-silenced SNU-620 cells exhibited slightly increased proliferation and cisplatin resistance. In addition, inhibition of NDRG2 decreased Fas expression and Fas-mediated cell death. Taken together, these data suggest that inactivation of NDRG2 may elicit resistance against anticancer drug and Fas-mediated cell death. Furthermore, case studies of gastric cancer patients indicate that NDRG2 expression may be involved in tumor progression and overall survival of the patients.
Apoptosis/*physiology ; Cell Line, Tumor ; Down-Regulation ; Fas Ligand Protein/*physiology ; Gene Expression Regulation, Neoplastic ; Humans ; Stomach Neoplasms/metabolism/*mortality/pathology ; Tumor Markers, Biological/*metabolism ; Tumor Suppressor Proteins/biosynthesis/genetics/immunology/*metabolism

OBJECTIVETo modify the isolation and culture method of Sertoli cells and investigate its' effects on xeno-lymphocytes apoptosis.

METHODSSertoli cells which was isolated from 2 - 4 week-old Sprague Dawley (SD) rats, were successfully prepared by collagenase type V, trypsin and DNase I and then identified by electron microscope. Viability and apoptosis of cultured cells were measured by flow cytometry. The apoptosis rates of Balb/c mouse lymphocytes were examined which were co-cultured with Sertoli cells of SD rats by flow cytometry, too. The expression of FasL, TGF-beta(1) and clusterin on Sertoli cells were detected by immunocytochemistry.

RESULTSIn the co-cultured system, Sertoli cells accounted for more than 90%. The viability of Sertoli cells was above 95% and the apoptosis rate was 10.87% +/- 3.87% in this study. The lymphocytes apoptosis ratio was 15.52% +/- 0.17% (P < 0.01). Streptavidin-biotin-peroxidase-complex immunochemistry staining showed that the Sertoli cells could express FasL, TGF-beta(1) and clusterin, respectively.

CONCLUSIONSIt indicates that the expression of FasL, TGF-beta(1) on the Sertoli cells might relate to the immune privilege, and it supposed to be benefit for xenotransplantation.

Animals ; Apoptosis ; Cell Culture Techniques ; methods ; Cell Survival ; physiology ; Cells, Cultured ; Clusterin ; metabolism ; Coculture Techniques ; Fas Ligand Protein ; metabolism ; Flow Cytometry ; Immunohistochemistry ; Lymphocytes ; cytology ; physiology ; Male ; Mice ; Mice, Inbred BALB C ; Microscopy, Electron, Transmission ; Rats ; Rats, Sprague-Dawley ; Sertoli Cells ; cytology ; metabolism ; ultrastructure ; Transforming Growth Factor beta ; metabolism

The aim of study was to explore the effects of NF-kappaB inhibitor Bay 11 - 7082 on Fas/FasL system and Fas-mediated apoptosis in HL-60 cells. The mRNA and protein expression levels of Fas, FasL and XIAP after treatment with Bay 11 - 7082 were detected by RT-PCR and FCM respectively. The level of sFasL was detected by ELISA before and after treatment with Bay 11 - 7082; apoptosis was detected by FCM before and after treatment with Bay 11 - 7082. The results showed that after treating HL-60 cells with Bay 11 - 7082, the mRNA and protein levels of FasL and XIAP were lower than that of controls, the difference was significant by statistic analysis (p < 0.05). Neither the mRNA and protein levels of Fas, nor the level of sFasL changed significantly (p > 0.05). Apoptotic rate of HL-60 cells treated with Bay 11 - 7082 was significantly higher as compared with controls (p < 0.05). It is concluded that Bay 11 - 7082 can enhance Fas-mediated apoptosis in HL-60 cells by down-regulation of FasL and XIAP levels.
Apoptosis ; drug effects ; Down-Regulation ; Fas Ligand Protein ; physiology ; Gene Expression Regulation, Leukemic ; HL-60 Cells ; Humans ; NF-kappa B ; antagonists & inhibitors ; Nitriles ; pharmacology ; RNA, Messenger ; metabolism ; Sulfones ; pharmacology ; X-Linked Inhibitor of Apoptosis Protein ; metabolism ; fas Receptor ; metabolism

OBJECTIVETo study the effect of total flaveos of Gymostemma pentaphyllum on the protein expression of apoptosis-associated Fas/FasL gene and tumor necrosis factor-alpha (TNF-alpha) concentration in cultured neonatal rat cardiomyocytes with hypoxia-reoxygenation (H/R).

METHODA cultured primary neonatal rat cardiomyocytes model with H/R was erected, experiments were divided into six groups, (1)control group, (2)H/R group, (3)15 mg x L(-1) TFG plus H/R group, (4)45 mg x L(-1) TFG plus H/R group, (5) 105 mg x L(-1) TFG plus H/R group, (6)105 mg x L(-1) TFG group. TNF-aconcentration in cultured cardiomyocytes with H/R, was determined by ELISA method, the protein expression of Fas/FasL genes were estimated by immunohisto-chemistry.

RESULTAfter cardiomyocytes were made with H/R, Compared with control group, the positive expression index (PEI) of Fas/FasL proteins in cardiomyocytes increased significantly, Compared with H/R groups, the PEI of Fas/FasL proteins were lower significantly in groups with different dosages of TFG (P < 0.05). TFG inhibited the secretion of TNF-alpha from myocardial cells and increased the survival rate of myocardial cells.

CONCLUSIONThe protein expression of apoptosis-associated Fas/FasL genes increased during H/R. The TFG can protect myocardium against H/R injury by decreasing the production of TNF-alpha, downregulating the protein expression of Fas/FasL genes, and then inhibiting myocyte apoptosis.

Animals ; Animals, Newborn ; Apoptosis ; drug effects ; Cell Hypoxia ; Cells, Cultured ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Enzyme-Linked Immunosorbent Assay ; Fas Ligand Protein ; metabolism ; Flavones ; isolation & purification ; pharmacology ; Gynostemma ; chemistry ; Immunohistochemistry ; Myocytes, Cardiac ; cytology ; drug effects ; metabolism ; Oxygen Consumption ; drug effects ; physiology ; Plants, Medicinal ; chemistry ; Rats ; Rats, Sprague-Dawley ; Tumor Necrosis Factor-alpha ; metabolism