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WISP1, a Wnt-induced secreted protein, has been found to have anticancer activity. ALL is a leading cause of death. Here we investigate the WISP1 effects on ALL Jurkat cells. Cell viability was assessed by CCK-8. Cell cycle and apoptosis were detected by flow cytometry. Mitochondrial membrane potential (MMP) was monitored using TMRM. Generation of reactive oxygen species (ROS) was quantified using DCFH-DA. Western blot was used to detect the expression of cell proliferation and apoptosis related genes. The results showed that knockdown of WISP1 significantly inhibited proliferation of Jurkat cells. Parallelly, cell cycle distribution was increased at G1 phase and apoptotic rate was induced after WISP1 knockdown. Furthermore, knockdown of WISP1 induced apoptosis of Jurkat cells was also associated with loss of MMP and generation of ROS. Western blot results showed that the protein expression p-AKT, PCNA, CDK1, P-ERK, CDK2, VEGF, VEGFR2 and Bcl2 were decreased, while the expression of Bax was up-regulated. In conclusion, WISP1 plays an important role in proliferation and apoptosis of Jurkat cells in mitochondria dependent pathway, the specific mechanisms need further study.  相似文献   
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[目的]研究木犀草素的分子特性,筛选并鉴定木犀草素抗骨性关节炎(osteoarthritis,OA)的潜在靶点。[方法]通过中药系统药理学数据库及分析平台(Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform,TCMSP)分析木犀草素的药理参数和分子特性;通过Swiss TargetPrediction和药物再定位及药物不良反应预测(predict drug repositioning and adverse drug reaction,DRAR-CPI)软件筛选木犀草素抗OA的潜在靶点;通过人类孟德尔遗传(Online Mendelian Inheritance in Man,OMIM)数据库、比较毒物遗传学数据库(The Comparative Toxicogenomics Database,CTD)和药物靶标数据库(Therapeutic Target Database,TTD)筛选已报道与OA相关的疾病靶点,并与木犀草素潜在靶点进行匹配,确定木犀草素抗OA的靶点,进一步采用分子对接软件对木犀草素抗OA的潜在靶点进行鉴定。[结果]木犀草素口服生物利用率为36.16%,药物相似度为0.25,具有很好的成药性;Swiss TargetPrediction和DRAR-CPI软件共筛选出6个潜在靶点,与OA直接相关的靶点有3个,经分子对接软件鉴定,间质胶原酶1/基质金属蛋白酶1(interstitial collagenase 1/matrix metalloproteinase 1,MMP1)和基质分解素-1/基质金属蛋白酶3(stromelysin-1/matrix metalloproteinase 3,MMP3)为木犀草素抗OA的潜在靶点。[结论]木犀草素可能通过结合MMP1和MMP3,下调其表达量,最终缓解OA的炎症反应。  相似文献   
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Objectives: The concept of platform switching has been introduced to implant therapy, however long‐term data are sparse. The aim of this study was to biochemically investigate the inflammatory response mediated by MMP‐8 to platform switching after 3 years of loading, in order to understand the long‐term effect of implant/abutment mismatching on peri‐implant health. Methods: A total of 70 implants had been inserted in the posterior maxilla in 26 patients and were randomly assigned to one of the four treatment regimens (implant diameter 3.8 [control group], 4.3 [Test group 1, T1], 4.8 [Test group 2, T2] and 5.5 mm [Test group 3, T3]). All implants were restored using a 3.8 mm abutment. In the test groups, this restoration resulted in a mismatching of 0.25–0.85 mm of implant–abutment diameters. Results: Thirty‐six months after prosthetic rehabilitation, peri‐implant sulcular fluid samples were taken from two aspects of all implants and from periodontally healthy adjacent teeth. Samples were processed in a conventional ELISA using monoclonal antibodies recognizing the active entity of MMP‐8. In the test groups, MMP‐8 mean values were 2.76 ng for T1 (SD: 2.91), 3.30 ng for T2 (SD: 1.94) and 3.18 ng for T3 (SD: 2.46). For the control group, MMP‐8 mean value was 3.6 ng (SD: 2.23), whereas 3.38 ng (SD: 2.2) was recorded at the adjacent teeth. There were no statistically significant differences in MMP‐8 values between the groups (P=0.113, Kruskal–Wallis). Conclusions: The presence of an implant/abutment mismatching specific for this prosthetic concept is compatible with long‐term peri‐implant health as demonstrated by analysis of a sensitive biomarker of the peri‐implant inflammatory response.  相似文献   
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Age-related changes in joint tissues lead to osteoarthritis (OA). Detection of early changes in OA patients may help to initiate treatments before the establishment of irreversible joint destruction. STR/ort mice develop with age a severe degenerative joint disease that resembles human OA thus allowing the investigation of biochemical markers as well as new treatments in an accelerated time frame. We have analyzed the changes in serum levels of different mediators during the early phases of idiopathic OA in STR/ort mice. Serum levels of matrix metalloproteinase-3 (MMP-3) but not those of tumor necrosis factor-α, interleukin(IL)-1β, IL-17 or prostaglandin E(2) correlated with histopathological changes in knees of STR/ort mice at 9 weeks. Treatment of animals with tin protoporphyrin IX (SnPP, 12 mg/kg/dayi.p.) for 4 weeks significantly reduced the progression of OA. Our data suggest that MMP-3 is a sensitive biomarker to detect early OA alterations and that SnPP could be a protective agent in OA.  相似文献   
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Background: Non-alcoholic fatty liver disease (NAFLD), including non-alcoholic steatohepatitis (NASH), appears to be increasingly common worldwide. Its histopathology and the effects of nutrition on liver function have not been fully determined. Aim: To elucidate the cellular mechanisms of NAFLD induced by a methionine-choline-deficient (MCD) diet in mice. Particular focus was placed on the role of phagocytic cells. Methods: Male C57BL/6 mice were fed an MCD diet for 30 weeks. A recovery model was also established wherein a normal control diet was provided for 2 weeks after a period of 8, 16, or 30 weeks. Results: Mice fed the MCD diet for ≥2 weeks exhibited severe steatohepatitis with elevated serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. Steatohepatitis was accompanied by the infiltration of CD68-positive macrophages (Kupffer cells). The severity of steatohepatitis increased in the first 16 weeks but was seen to lessen by week 30. Fibrosis began to develop at 10 weeks and continued thereafter. Steatohepatitis and elevated serum hepatic enzyme concentrations returned to normal levels after switching the diet back to the control within the first 16 weeks, but fibrosis and CD68-positive macrophages remained. Conclusions: The histopathological changes and irreversible fibrosis seen in this model were caused by prolonged feeding of an MCD diet. These results were accompanied by changes in the activity of CD68-positive cells with temporary elevation of CCL-2, MMP-13, and MMP-9 levels, all of which may trigger early steatohepatitis and late fibrosis through phagocytosis-associated MMP induction.  相似文献   
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The benefits of estrogens on bone health are well established; how estrogens signal to regulate bone formation and resorption is less well understood. We show here that 17β‐estradiol (E2)‐induced apoptosis of bone‐resorbing osteoclasts is mediated by cleavage and solubilization of osteoblast‐expressed Fas ligand (FasL). U2OS‐ERα osteoblast‐like cells expressing an EGFP‐tagged FasL at the C‐terminus showed decreased fluorescence after E2 treatment, indicative of a cleavage event. Treatment of U2OS‐ERα cultures with a specific MMP3 inhibitor in the presence of E2 blocked FasL cleavage and showed an increase in the number of EGFP‐FasL+ cells. siRNA experiments successfully knocked down MMP3 expression and restored full‐length FasL to basal levels. E2 treatment of both human and murine primary osteoblasts showed upregulation of MMP3 mRNA expression, and calvarial organ cultures showed increased expression of MMP3 protein and colocalization with the osteoblast‐specific RUNX2 after E2 treatment. In addition, osteoblast cell cultures derived from ERαKO mice showed decreased expression of MMP3 but not MMP7 and ADAM10, two known FasL proteases, demonstrating that ERα signaling regulates MMP3. Also, conditioned media of E2‐treated calvarial osteoblasts showed an approximate sixfold increase in the concentration of soluble FasL, indicating extensive cleavage, and soluble FasL concentrations were reduced in the presence of a specific MMP3 inhibitor. Finally, to show the role of soluble FasL in osteoclast apoptosis, human osteoclasts were cocultured with MC3T3 osteoblasts. Both a specific MMP3 inhibitor and an MMP inhibitor cocktail preserved osteoclast differentiation and survival in the presence of E2 and demonstrate the necessity of MMP3 for E2‐induced osteoclast apoptosis. These experiments further define the molecular mechanism of estrogen's bone‐protective effects by inducing osteoclast apoptosis through upregulation of MMP3 and FasL cleavage. © 2013 American Society for Bone and Mineral Research  相似文献   
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