Rosiglitazone down-regulates lipopolysaccharide-induced expression of CD40 and intercellular adhesion molecule 1 in rat peritoneal mesothelial cells through a NF-κB dependent mechanism

Objective To investigate the effect and mechanism by which PPARγ ligand, rosiglitasone, regulates the expression of CD40 and intercellular adhesion molecule 1 (ICAM-1) in the rat peritoneal mesothelial cells (RPMCs) induced by lipopolysaccharide (LPS). Methods RPMCs were harvested from Sprague-Dawley rat peritoneal cavity and maintained under defined in vitro conditions. The cells were randomly divided into groups as follows: medium, LPS (5 mg/L), LPS (5 mg/L)+BAY11-7085(5 μmol/L, NF-κB inhibitor), rosiglitazone (10 μmol/L or 20 μmol/L, peroxisome proliferator-activated receptor γ activator), LPS (5 mg/L)+rosiglitazone (10 μmol/L)+GW9662 (3 μmol/L, peroxisome proliferator-aetivatcd receptor γ antagonist), and LPS (5 mg/L)+vehicle (DMSO 0.2 ml/L). The expressions of CD40 and ICAM-1 RNA in RPMCs were examined by RT-PCR after 3 hour treatment, and the protein expressions of CD40, ICAM-1, p-NF-κB p65 and p-IκBα were examined by Western blot or immunofluorescence after 24 hour treatment. Results Following treatment with LPS, both the expressions of CD40 and ICAM-1 protein in RPMCs were up-regulated significantly (P<0.05), and the phosphoralation of p65 was increased greatly (1.10±0.17 vs 0.55±0.06, P<0.05). BAY11-7085 (5 μmol/L) significantly decreased the protein expression of p-p65 (0.22±0.11 vs 1.10±0.17, P<0.01), CD40 (0.34±0.02 vs 0.50±0.06, P<0.05) and ICAM-1 (0.35±0.16 vs 0.74±0.03, P<0.05). Pretreated with rosiglitazone for 3 h then added with LPS for 1 h, the levels of p-p65, CD40 and ICAM-1 in RPMCs were significantly decreased compared with those of LPS group (0.77±0.08 vs 0.90±0.10, P相似文献   

Adherence of Staphylococcus aureus to cultures of human peritoneal mesothelial cells

Strains of Staphylococcus aureus, isolated from the effluentof patients with peritonitis on CAPD (continuous ambulatoryperitoneal dialysis), adhered well to both cultured human mesothelialcells and to fibronectin, but not to laminin or gelatin. Mesothelialcells grown in medium M199 exhibited more surface fibronectincompared to cells grown in MEM-Dval and demonstrated higherlevels of S. aureus adherence. Soluble fibronectin concentrations up to lOµg/ml increasedthe adherence of S. aureusto cultured mesothelial cells. Thedose-response curve was consistent with the binding of fibronectinto a saturable receptor of apparent dissociation constant (K_D)= 1.7xlO^–10 M. This corresponds closely to the K_D (2xlO^–10M) of the staphylococcal fibronectin-binding protein. S. aureus adherence was increased following the preincubationof mesothelial cell monolayers with interleukin-1 and was maximalafter 6 h preincubation. Treating mesothelial cells with interferon-gammafor 48–72 h reduced the adherence of S. aureus.     

大鼠壁胸膜通透性的电镜观察

目的观察大鼠壁胸膜的通透性，胸膜腔内物质的吸收途径。方法向大鼠胸膜腔内注射示踪剂，应用光镜、透射电镜方法观察壁胸膜的物质吸收途径以及壁胸膜间皮的形态变化。结果壁胸膜表面覆盖一层连续的间皮细胞，间皮细胞按形态可分为立方形和扁平形问皮细胞，立方形间皮细胞下的结缔组织内存在大量的毛细淋巴管。由毛细淋巴管内皮细胞突起穿过间皮下结缔组织与问皮细胞相连接而形成的间皮孔，是物质吸收的主要途径。结论壁胸膜通过三种途径吸收物质：①间皮孔的吸收作用；②问皮细胞的吞噬作用；③通过问皮细胞间裂隙吸收。     

Increased matrix metalloproteinase-9 activity in human ovarian cancer cells cultured with conditioned medium from human peritoneal tissue

Ovarian cancer cells disseminate by attachment to the peritoneal mesothelial cell surface of the abdominal cavity. We therefore investigated the influence of conditioned medium (CM) from human peritoneal tissues and mesothelial cells on the secretion of matrix metalloproteinases (MMPs) by ovarian cancer cells. The molecular weights of MMPs stimulating factors derived from human peritoneal tissues and mesothelial cells were estimated using microconcentrators with various cut-off membranes. Human peritoneal tissues were obtained from 12 surgical patients, and mesothelial cells were isolated from three peritoneal specimens. Exposure to CM from peritoneal tissue caused a concentration-dependent increase of the MMP-2 and MMP-9 bands in CM from NOM1 ovarian cancer cells, as shown by zymography. There was a significant difference in the increase of MMP-2 and MMP-9 (2.46-fold and 7.14-fold, respectively, at 0.4mg/ml protein; P < 0.005). CM from mesothelial cells also significantly increased the secretion of MMP-9 by NOM1 cells. The molecular size of possible MMP-9-stimulating factors secreted by peritoneal tissues and mesothelial cells was above M 100000. Further, CM of peritoneal tissues and mesothelial cells also induced the invasiveness of NOM1 cells. These findings suggest that mesothelial cells may secrete some factors which predominantly induce the MMP-9 production and increase invading cell numbers.     

Immunohistochemical evidence for mesothelial origin of paratesticular adenomatoid tumour

AIMS: To investigate the histogenesis of paratesticular adenomatoid tumour by use of immunohistochemical markers for a variety of carcinomas and mesothelioma. METHODS AND RESULTS: Immunohistochemical staining of sections from 12 cases of paratesticular adenomatoid tumour was undertaken using primary antibodies to antigens expressed by benign epithelial cells and carcinoma (cytokeratin AE1/AE3, cytokeratin 34ssE12, epithelial membrane antigen, MOC-31, Ber-EP4, CEA, B72.3, LEA.135, Leu M1), stromal and vascular markers (vimentin, CD34, factor VIII), and mesothelioma-associated antigens (thrombomodulin, HBME-1, OC 125) and p53 protein. There was absence of immunohistochemical expression of epithelial/carcinoma markers MOC-31, Ber-EP4, CEA, B72.3, LEA.135, Leu M1 and to factor VIII and CD34. All tumours expressed cytokeratin AE1/AE3, epithelial membrane antigen and vimentin, with weak expression of cytokeratin 34ssE12 in 25% of tumours. Each tumour showed expression of thrombomodulin, HBME-1 and OC 125 in a membranous distribution. p53 protein expression was not detected. CONCLUSIONS: The immunohistochemical profile of paratesticular adenomatoid tumour is strongly supportive of a mesothelial cell origin.     

Expression pattern of Popdc2 during mouse embryogenesis and in the adult.

The Popdc2 gene is a member of the Popeye domain containing gene family encoding membrane proteins with prominent expression in striated and smooth muscle tissue. After introducing a LacZ reporter gene into the Popdc2 locus, expression was studied during embryonic development and postnatal life. At embryonic day (E) 7.5, expression was present in cardiac and extraembryonic mesoderm. At E10.5, expression was found in heart, somites, and mesothelial cells lining the coelom. At E12.5, expression was present in the coelomic mesothelium, pericardial and myocardial layer of the heart, skeletal muscle, bladder, gut, and umbilical vessels. Postnatal expression was found in cardiac and skeletal muscle and in the smooth muscle layer of colon, rectum, and bladder. In the stomach, Popdc2 was exclusively present in the pyloric epithelium. In conclusion, Popdc2 is expressed in various muscle and nonmuscle cell types during embryonic development and in postnatal life.     

Critical role for SV40 small-t antigen in human cell transformation

Defining the ability of simian virus 40 (SV40) to transform human cells has become of even greater importance with the increased understanding that this virus may play a role in some human malignancies. This report documents the requirement for viral small-t (ST) antigen in large-T (LT)-driven transformation of primary fibroblasts, a requirement that cannot be met by a well-known oncogene, c-Ha-ras (EJ-ras), which can cooperate with LT in rodent systems. The cellular gene telomerase is not essential for transformation, although transformed clones are not immortal without it. Similarly, an immortal mesothelial cell line has been developed using LT and telomerase. Immortalized mesothelial cells are morphologically normal, but can be transformed by introduction of ST, or ST + ras, but not by ras alone. It is likely that ST will be required along with LT for transformation of most human cell types.     

人腹膜间皮细胞的培养及特征

目的 :建立人腹膜间皮细胞 (HPMC)培养模型 ,检测HPMC细胞外基质蛋白及白细胞介素 (IL - 8)的表达。方法 :采用胰蛋白酶 -EDTA消化法 ,从人的腹膜组织中分离HPMC。采用形态学和链霉菌抗生物素蛋白 过氧化物酶连接法 (即SP法 ) ,对培养细胞进行鉴定。采用SP法检测HPMC纤维连接蛋白 (FN)、胶原Ⅲ和胶原V及转化生长因子 (TGF) β1表达。采用逆转录多聚酶链反应 (RT -PCR)检测HPMCIL - 8mRNA和FNmRNA的表达。结果 :光镜示细胞融合后呈多边形 ,超微结构下可见丰富的微绒毛和内质网 ,免疫组化染色结果示HPMC可表达角蛋白 ,波形蛋白 ,胶原Ⅲ ,FN ,TGFβ1蛋白 ,Ⅷ因子、胶原V表达阴性。人腹膜间皮细胞亦表达FNmRNA和IL - 8mRNA。结论 :HPMC培养模型的建立 ,可为进一步研究腹膜纤维化的防治及IL - 8在腹膜透析中的作用提供理论依据。     

大鼠膈腹膜间皮孔的电镜观察

用扫描电镜和透射电镜观察了正常大鼠膈腹膜间皮，并观察了腹膜腔内注射中国墨汁和兔血液后大鼠膈腹膜间皮的变化以及腹膜腔和间皮下毛细淋巴管的关系。