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81.
Xenotransplantation has been considered an alternative to the moderate shortage of donor organs for transplantation. To achieve successful xenotransplatation, there is the need to overcome immune rejection. Although, hyperacute rejection has been overcome by α1,3-galactosyltransferase knockout pig, cellular immune rejection remains as a subsequent barrier. Interleukin-10 (IL-10) is known as an anti-inflammatory and immunomodulatory cytokine which has been shown to limit inflammatory responses by inhibiting macrophage activation in several animal experiments. To study the effect of human IL-10 (hIL-10) on pig-to-human xenotransplantation, porcine kidney epithelial cell line (PK(15)) expressing hIL-10 was established. The cytotoxicity of macrophages decreased by hIL-10 from transgenic cells. Furthermore, there is a decreased production of pro-inflammatory cytokines, tumor necrosis factor-α and interleukin-23, and increased anti-inflammatory cytokines like IL-10, but not transforming growth factor beta, in the presence of hIL-10. Also, macrophage polarization toward M2-like phenotype were induced by hIL-10 from transgenic PK(15) cells. Finally, we suggest that the cytotoxicity of human macrophages was reduced by hIL-10 from transgenic cells, inducing M2-like macrophage polarization. Therefore, these results show that hIL-10 transgenic pig can be used as a model to overcome acute immune rejection in pig-to-human xenotransplantation.  相似文献   
82.
Inflammation is a process triggered by pro-inflammatory cytokines and anti-inflammatory molecules. Therefore, it is of interest to document the anti-inflammatory activity of Stachydrine and Sakuranetin against the inflammatory target proteins IL-6 and TNF-α by using molecular docking analysis. Both compounds showed good binding features with the selected target proteins. Compared to Sakuranetin, the Stachydrine have low binding energy and good hydrogen bond interactions. Hence, data show that Stachydrine possessed high and specific inhibitory activity on tumor necrosis factor-α and interleukin-6.  相似文献   
83.
Parasitic food-borne diseases and chronic social stress are frequent attributes of day-to-day human life. Therefore, our aim was to model the combined action of chronic Opisthorchis felineus infection and repeated social defeat stress in C57BL/6 mice. Histological examination of the liver revealed inflammation sites, pronounced periductal fibrosis, and cholangiofibrosis together with proliferation of bile ducts and hepatocyte dystrophy in the infected mice, especially in the stress-exposed ones. Simultaneously with liver pathology, we detected significant structural changes in the cerebral cortex. Immunohistochemical analysis of the hippocampus indicated the highest increase in numerical density of Iba 1-, IL-6-, iNOS-, and Arg1-positive cells in mice simultaneously subjected to the two adverse factors. The number of GFAP-positive cells rose during repeated social defeat stress, most strongly in the mice subjected to both infection and stress. Real-time PCR analysis showed that the expression of genes Aif1 and Il6 differed among the analysed brain regions (hippocampus, hypothalamus, and frontal cortex) and depended on the adverse factors applied. In addition, among the brain regions, there was no consistent increase or decrease in these parameters when the two adverse treatments were combined: (i) in the hippocampus, there was upregulation of Aif1 and no change in Il6 expression; (ii) in the hypothalamus, expression levels of Aif1 and Il6 were not different from controls; and (iii) in the frontal cortex, Aif1 expression did not change while Il6 expression increased. It can be concluded that a combination of two long-lasting adverse factors, O. felineus infection and repeated social defeat stress, worsens not only the hepatic but also brain state, as evidenced behaviorally by disturbances of the startle response in mice.  相似文献   
84.
Fibroblast growth factor 21 (FGF21) as a metabolic stress hormone, is mainly secreted by the liver. In addition to its well‐defined roles in energy homeostasis, FGF21 has been shown to promote remyelination after injury in the central nervous system. In the current study, we sought to examine the potential roles of FGF21 in the peripheral nervous system (PNS) myelination. In the PNS myelin development, Fgf21 expression was reversely correlated with myelin gene expression. In cultured primary Schwann cells (SCs), the application of recombinant FGF21 greatly attenuates myelination‐associated gene expression, including Oct6, Krox20, Mbp, Mpz, and Pmp22. Accordingly, the injection of FGF21 into neonatal rats markedly mitigates the myelination in sciatic nerves. On the contrary, the infusion of the anti‐FGF21 antibody accelerates the myelination. Mechanistically, both extracellular signal‐regulated kinase (ERK) and p38 mitogen‐activated protein kinase (MAPK) were stimulated by FGF21 in SCs and sciatic nerves. Following experiments including pharmaceutical intervention and gene manipulation revealed that the p38 MAPK/c‐Jun axis, rather than ERK, is targeted by FGF21 for mediating its repression on myelination in SCs. Taken together, our data provide a new aspect of FGF21 by acting as a negative regulator for the myelin development process in the PNS via activation of p38 MAPK/c‐Jun.  相似文献   
85.
目的: 探讨IL-21单克隆抗体对MRL/lpr狼疮小鼠的免疫治疗作用。方法: 将20只MRL/lpr狼疮小鼠随机分为模型组和治疗组,每组10只;同年龄同性别C57BL/6小鼠10只作为正常组。治疗组小鼠每周腹腔注射IL-21单克隆抗体(100 μg),正常组及模型组小鼠每周腹腔注射等量生理盐水(100 μg),连续干预8周。干预结束后观察小鼠皮毛、活动等一般性状及浅表淋巴结大小,并采集小鼠血液、尿液及肾脏标本。采用Western blot法检测三组小鼠肾组织中IL-21蛋白表达情况;采用ELISA法比较三组小鼠血清抗ds-DNA抗体、ANA抗体、血尿素氮、肌酐和炎症因子IL-17A、TGF-β1水平;采用生物化学法比较三组小鼠24 h尿蛋白水平。结果: 与正常组比较,模型组小鼠肾组织IL-21、血清抗ds-DNA、ANA抗体水平、尿素氮、肌酐、IL-17A浓度及24 h尿蛋白水平均升高(P<0.05),TGF-β1浓度降低(P<0.01);与模型组比较,治疗组小鼠肾组织IL-21、血清抗ds-DNA、ANA抗体水平、尿素氮、肌酐、IL-17A浓度、24 h尿蛋白水平均降低(P<0.05),TGF-β1浓度升高(P<0.01)。结论: 腹腔注射IL-21单克隆抗体可改善MRL/lpr狼疮小鼠免疫功能与肾损害,提示治疗机制可能与重塑Th17/Treg相关细胞因子平衡有关。  相似文献   
86.
Long non-coding RNAs (lncRNAs) have been highlighted as attractive markers for diagnosis and prognosis as well as new therapeutic targets in multiple cancers, including nasopharyngeal carcinoma (NPC). Here, we attempted to investigate the underlying regulatory role of the lncRNA maternally expressed gene 3 (MEG3) in NPC development. As determined by RT-qPCR, MEG3 expression was down-regulated in NPC cells. Online RNA crosstalk analysis predicted the binding of miR-21 to MEG3 and PTEN, respectively. MEG3 was validated to bind to miR-21 while PTEN was identified as a target of miR-21 by dual-luciferase reporter gene assay. Exogenous transfection was done to change the levels of MEG3, miR-21 and PTEN in HK-1 cells to investigate their effects on the autophagy and apoptosis of NPC cells. The results suggested that MEG3 overexpression in HK-1 cells up-regulated PTEN and down-regulated miR-21, by which MEG3 further inhibited autophagy and apoptosis ability of NPC cells. The tumour formation ability was tested after injecting the HK-1 cells into nude, mice and tumour growth was monitored. Consistently, MEG3 overexpression inhibited the tumour formation in vivo. Collectively, MEG3 promotes the autophagy and apoptosis of NPC cells via enhancing PTEN expression by binding to miR-21.  相似文献   
87.
Previous studies identified the involvement of phosphoinositide-specific phospholipase C (PLC) γ1 in some events of chondrocytes. This study aims to investigate whether and how PLCγ1 modulates autophagy to execute its role in osteoarthritis (OA) progression. Rat normal or human OA chondrocytes were pretreated with IL-1β for mimicking or sustaining OA pathological condition. Using Western blotting, immunoprecipitation, qPCR, immunofluorescence and Dimethylmethylene blue assays, and ELISA and transmission electron microscope techniques, we found that PLCγ1 inhibitor U73122 enhanced Collagen II, Aggrecan and GAG levels, accompanied with increased LC3B-II/I ratio and decreased P62 expression level, whereas autophagy inhibitor Chloroquine partially diminished its effect. Meanwhile, U73122 dissociated Beclin1 from Beclin1-IP3R-Bcl-2 complex and blocked mTOR/ULK1 axis, in which the crosstalk between PLCγ1, AMPK, Erk and Akt were involved. Additionally, by haematoxylin and eosin, Safranin O/Fast green, and immunohistochemistry staining, we observed that intra-articular injection of Ad-shPLCγ1-1/2 significantly enhanced Collagen and Aggrecan levels, accompanied with increased LC3B and decreased P62 levels in a rat OA model induced by anterior cruciate ligament transection and medial meniscus resection. Consequently, PLCγ1 inhibition-driven autophagy conferred cartilage protection against OA through promoting ECM synthesis in OA chondrocytes in vivo and in vitro, involving the crosstalk between PLCγ1, AMPK, Erk and Akt.  相似文献   
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90.
目的:构建针对IL-1α基因的shRNA表达载体,筛选能够抑制Hela229细胞内源性IL-1α表达的shRNA,建立无内源性IL-1d表达的Hela229稳定细胞系.方法:根据shRNA的设计原则,以IL-1 αcDNA oligo为模板设计一段21 bp核苷酸目标序列,构建成siRNA的DNA模板并克隆到shRNA表达载体pRNAT-U6.1/Neo中,获得靶向抑制IL-1α基因的重组shRNA质粒,转染Hela229细胞,经G418筛选后获得单克隆稳定细胞株,用ELISA方法在蛋白水平上检测IL-1α基因的沉默效果.结果:经酶切鉴定和测序分析确定IL-1 α-shRNA重组质粒构建正确,ELISA筛选出能够显著抑制内源性IL-1α表达的shRNA,获得沉默内源性IL-1 α表达的单克隆稳定的Hela229细胞株.结论:靶向IL-1α基因的重组shRNA表达质粒可显著抑制Hela229细胞内源性IL-1α的表达,成功构建靶向IL-1α基因沉默的Hela229稳定细胞系.  相似文献   
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