OBJECTIVETo observe the effect of TSP-2, the antibody of Toll-like receptor 2 extracellular domain, on the expression and DNA-binding activity of nuclear factor-κB (NF-κB) p65 protein in mice with ulcerative colitis (UC).

METHODSSixty BALB/c mice were randomized equally into normal control group, UC model group, TSP-2 treatment group, and rabbit IgG treatment group. In the latter 3 groups, the mice were fed with 5% DSS (C6H7Na3O14S3) solution for 7 days to induced UC, followed then by treatment with daily injections of TSP-2 or rabbit IgG as appropriate for 7 days. The disease activity index was recorded during the treatment. The colitis tissues were collected after the treatments for HE staining and detecting the expression and DNA-binding activity of NF-κB p65 in the colon mucosa by Western blotting and ELISA.

RESULTSThe DNA binding activity and expressions of NF-κB P65 protein increased significantly in UC model group (P<0.05). TSP-2 treatment group significantly decreased the disease activity index (P<0.05) and lowered the DNA-binding activity and expression of NF-κB P65 protein (P<0.05) in the UC mouse models, while rabbit IgG produced no such effects (P>0.05).

CONCLUSIONTSP-2 can suppress the DNA-binding activity and protein expressions of NF-κB P65 and regulate excessive immune response in the intestines to ameliorate ulcerative colitis in mice.

Animals ; Colitis, Ulcerative ; immunology ; metabolism ; Male ; Mice ; Mice, Inbred BALB C ; Rabbits ; Thrombospondins ; pharmacology ; Transcription Factor RelA ; genetics ; metabolism

OBJECTIVETo investigate the expression of R-spondin1 (RSpo1) in the intestinal epithelium of mice with intestinal ischemia-reperfusion injury and explore its significance.

METHODSFifty normal male Kunming mice were randomized into sham-operated group (n=10) and intestinal ischemia-reperfusion injury group (n=40), and in the latter group, the mice were subjected to 20-min intestinal mesenteric artery occlusion followed by reperfusion for 6, 12, 24, or 48 h. Enzyme-linked immunosorbent assay (ELISA) and RT-PCR were used to detect intestinal RSpo1 expression of the mice.

RESULTSThe results of RT-PCR and ELISA showed that RSpo1 expression was significantly decreased in mice at 6 h of reperfusion following the intestinal ischemia (P<0.05), and increased gradually with prolonged repersuion time, reaching the peak level at 24 h (P<0.05). The expression underwent rapid decrease afterwards to a significantly lower level than that in the control group at 48 h (P<0.05).

CONCLUSIONIntestinal ischemia-reperfusion injury may inhibit expression of RSpo1 in the early stage, and enhance its expression in the middle stage. RSpo1 can promote proliferation and differentiation of intestinal epithelial stem cells and plays an important role in the repair intestinal mucosal damage.

Animals ; Cell Proliferation ; Intestinal Mucosa ; cytology ; metabolism ; Intestines ; blood supply ; metabolism ; Male ; Mice ; Random Allocation ; Reperfusion Injury ; metabolism ; Stem Cells ; cytology ; Thrombospondins ; genetics ; metabolism

OBJECTIVETo study the possible role of human thrombospondin (hPWTSR) in gastric cancer and explore its potential to serve as the target for gastric cancer diagnosis and intervention.

METHODSUsing pLexA-hPWTSR as the bait, a premade pB42AD-based fetal brain cDNA library was constructed to identify the interacting proteins. The expression pattern of hPWTSR in gastric cancer tissues and a gastric cancer cell line was observed to investigate the correlation between hPWTSR expression and the biological behaviors of the tumor. The possibility of hPWTSR as a potential gastric cancer marker was evaluated.

RESULTSFifty-seven independent clones were isolated from 107 clones screened. Sequence analysis indicated that the 57 positive clones represented the products of 12 genes. A RT-PCR-based expression pattern revealed that the expression of hPWTSR in gastric cancer tissues and a gastric cancer cell line was lower than that in the corresponding normal tissues, but no mutations were identified by the subsequent sequence analysis.

CONCLUSIONShPWTSR interacts with adhesion-related proteins and tumor-related genes, and its expression is lowered in gastric cancer tissues and gastric cancer cell line. hPWTSR might play a role in gastric cancer development, especially in metastasis and might be used as a potential gastric cancer marker. The exact functions of hPWTSR and its potential clinical value still await further study.

Biomarkers, Tumor ; genetics ; metabolism ; Cell Line, Tumor ; Gene Expression Profiling ; methods ; Gene Expression Regulation, Neoplastic ; Humans ; Protein Binding ; Reverse Transcriptase Polymerase Chain Reaction ; Stomach Neoplasms ; genetics ; metabolism ; pathology ; Thrombospondins ; genetics ; metabolism

Vascular smooth muscle cells (VSMCs) undergo phenotypic changes in response to vascular injury such as angioplasty. Protein kinase G (PKG) has an important role in the process of VSMC phenotype switching. In this study, we examined whether rosiglitazone, a peroxisome proliferator-activated receptor (PPAR)-gamma agonist, could modulate VSMC phenotype through the PKG pathway to reduce neointimal hyperplasia after angioplasty. In vitro experiments showed that rosiglitazone inhibited the phenotype change of VSMCs from a contractile to a synthetic form. The platelet-derived growth factor (PDGF)-induced reduction of PKG level was reversed by rosiglitazone treatment, resulting in increased PKG activity. This increased activity of PKG resulted in phosphorylation of vasodilator-stimulated phosphoprotein at serine 239, leading to inhibited proliferation of VSMCs. Interestingly, rosiglitazone did not change the level of nitric oxide (NO) or cyclic guanosine monophosphate (cGMP), which are upstream of PKG, suggesting that rosiglitazone influences PKG itself. Chromatin immunoprecipitation assays for the PKG promoter showed that the activation of PKG by rosiglitazone was mediated by the increased binding of Sp1 on the promoter region of PKG. In vivo experiments showed that rosiglitazone significantly inhibited neointimal formation after balloon injury. Immunohistochemistry staining for calponin and thrombospondin showed that this effect of rosiglitazone was mediated by modulating VSMC phenotype. Our findings demonstrate that rosiglitazone is a potent modulator of VSMC phenotype, which is regulated by PKG. This activation of PKG by rosiglitazone results in reduced neointimal hyperplasia after angioplasty. These results provide important mechanistic insight into the cardiovascular-protective effect of PPARgamma.
Animals ; Aorta/injuries/metabolism/*pathology ; Calcium-Binding Proteins/genetics/metabolism ; Cell Proliferation ; Cyclic GMP/metabolism ; Cyclic GMP-Dependent Protein Kinases/genetics/*metabolism ; Hyperplasia/metabolism ; Microfilament Proteins/genetics/metabolism ; Muscle, Smooth, Vascular/metabolism/pathology ; Myocytes, Smooth Muscle/drug effects/*metabolism ; Nitric Oxide/metabolism ; PPAR gamma/agonists/*metabolism ; Promoter Regions, Genetic ; Rats ; Rats, Sprague-Dawley ; Sp1 Transcription Factor/metabolism ; Thiazolidinediones/pharmacology ; Thrombospondins/genetics/metabolism ; Tunica Intima/metabolism/*pathology ; Vascular System Injuries/*metabolism/pathology

OBJECTIVETo observe the effect of the antibody TSP-2 against a single epitope of mouse Toll-like receptor 2 extracellular domain (mTLR2ECD) on the expression of nuclear factor-kappa B (NF-κB) and cytokines in the intestinal tissue of septic mice.

METHODSMale BALB/c mice were randomly divided into 4 groups, namely the sham-operated group, model group, TSP-2 treatment group and rabbit IgG treatment group. Sepsis was induced by cecal ligation and puncture (CLP), and at 6, 12 or 24 h after the operation, the ileal tissues were harvested from the mice for HE staining. NF-κB expression was detected with immunohistochemistry. Tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) mRNA expressions were detected with qRT-PCR and their protein expressions by ELISA.

RESULTSThe NF-κB expression in the intestinal tissue significantly increased in the model group as compared with that in the sham- operated group, and decreased after TSP-2 treatment. The model group also showed significantly increased expression levels of TNF-α and IL-6 mRNA and protein in the intestinal tissue (P<0.05), which were lowered by TSP-2 (P<0.05) but not by rabbit IgG treatment (P>0.05).

CONCLUSIONThe TSP-2 antibody can protect the intestine and delay the development of sepsis by inhibiting NF-κB activation and down-regulating TNF-α and IL-6 expressions in mice.

Animals ; Antibodies ; pharmacology ; Immunodominant Epitopes ; immunology ; Interleukin-6 ; genetics ; metabolism ; Intestinal Mucosa ; metabolism ; Male ; Mice ; Mice, Inbred BALB C ; NF-kappa B ; genetics ; metabolism ; Random Allocation ; Receptors, Cell Surface ; immunology ; Sepsis ; metabolism ; Thrombospondins ; immunology ; Toll-Like Receptor 2 ; immunology ; Tumor Necrosis Factor-alpha ; genetics ; metabolism