Retraction Note: Adiponectin administration alleviates DSS-induced colonic inflammation in Caco-2 cells and mice

Inflammation Research - The Editors have retracted this article because the corresponding author raised concerns over the source of the data presented in this article, but did not provide any...     

脂联素减轻高糖诱导的人血管内皮细胞系损伤

目的 观察脂联素(APN)对高糖诱导血管内皮细胞系损伤的保护作用及NF-κB与LOX-1蛋白表达在其中的作用.方法 30 mmol/LD-葡萄糖作用于HUVEC-12(人脐静脉内皮细胞系),不同浓度的脂联素(10、20和40 μg/mL)作用48 h及20μg/mL脂联素作用不同时间(12、24、48和72 h)后,倒置相差显微镜观察内皮细胞形态,Western blot检测核转录因子NF-κB和LOX-1蛋白表达,间接免疫荧光法检测NF-κB核转位情况.结果 脂联素作用于D-葡萄糖诱导的HUVEC-12,内皮细胞形态改善,折光性增强,胞内颗粒物减少,细胞排列相对规整;同时,LOX-1蛋白表达下调(P＜0.05),NF-κB活性降低(P＜0.05),并呈现时间和浓度依赖性(n=3,P＜0.05).结论 脂联素可能通过NF-κB信号通路引起LOX-1蛋白表达下调,从而发挥其对高糖诱导血管内皮细胞损伤的保护作用.     

Conversion of human colonic adenoma cells to adenocarcinoma cells through inflammation in nude mice

The roles of inflammation in the malignant progression of tumors during multistep carcinogenesis have been much discussed but remain to be elucidated. To determine the direct contribution of inflammation to colon carcinogenesis, we established a new model of progression of human colonic adenoma cells using a nude mouse; the progression is accelerated by coimplantation of a plastic plate. The FPCK-1-1 cell line, derived from a colonic polyp in a patient with familial adenomatous polyposis, is nontumorigenic when injected subcutaneously into nude mice in a cell suspension of up to 5 x 106 cells per mouse. However implantation of 1 x 10(5) FPCK-1-1 cells attached to a plastic plate induced first acute and then chronic inflammation, and formed progressively growing tumors that were histologically determined as moderately differentiated adenocarcinoma in 65% of mice. Moreover cell lines established from the growing tumors were found to be tumorigenic when injected into mice even without a plastic plate. The tumor arising from the adenoma cells implanted attached to a plastic plate was surrounded by highly proliferating fibrous stroma. This fibrous tissue was considered essential for malignant progression, rather than for attachment to the plastic plate substrate, because the tumors were formed after injection of FPCK-1-1 cells into the fibrous tissue from which the plastic plate had been removed before the cell injection. The conditioned medium (CM) obtained from the fibroblasts derived from a plastic plate-associated stromal tissue was found to contain factors that stimulated growth of FPCK-1-1 cells, but not of the derivative progressor cell lines. The factor was stable to heating and neuraminidase treatment, but labile to trypsin treatment. The main growth-potentiating activity was contained in the fraction larger than 100 kDa. In contrast, the activity to promote FPCK-1-1 cell growth was not present in the CM of subcutaneous fibroblasts from untreated nude mice or the fibroblast cell lines C3H10T 1/2 and NIH3T3. These results demonstrated that inflammation-associated stroma promoted the conversion of colonic adenoma cells to adenocarcinoma cells.     

薯蓣皂苷减轻卵清蛋白诱导的过敏性哮喘小鼠的气道炎症

目的探讨薯蓣皂苷对卵清蛋白(ovalbumin,OVA)诱导的过敏性哮喘小鼠中过敏性支气管炎的影响及机制。方法24只小鼠随机分为对照组、OVA组、OVA+30 mg/kg薯蓣皂苷组和OVA+60 mg/kg薯蓣皂苷组,每组纳入6只小鼠。全自动生化仪检测各组支气管肺泡灌洗液(bronchoalveolar lavage fluid,BALF)中嗜中性粒细胞、嗜酸性粒细胞和单核细胞的数量;ELISA法检测BALF中促炎因子IL-1β、IL-4、IL-5和TNF-α的含量;PAS染色法观察肺组织黏液分泌情况并对黏液分泌程度进行评分;免疫组化法观察肺组织p-NF-κB p65的表达和分布情况;Western blotting法检测肺组织中p-IκB和NF-κB p65的蛋白表达水平。结果薯蓣皂苷可降低过敏性哮喘小鼠BALF中炎性细胞数量,同时降低BALF中促炎因子IL-1β、IL-4、IL-5和TNF-α的水平以及肺部黏液的分泌和NF-κB的活化水平。结论薯蓣皂苷能减轻过敏性哮喘小鼠的气道炎症,且其抗炎作用与抑制NF-κB活化有关。     

Quercetin and kaempferol suppress immunoglobulin E-mediated allergic inflammation in RBL-2H3 and Caco-2 cells

Objective

We investigated the inhibitory effects of quercetin and kaempferol treatment on the suppression of immunoglobulin E (IgE)-mediated allergic responses in relation to intestinal epithelium barrier function in RBL-2H3 and Caco-2 cells.

Methods

RBL-2H3 cells as a model of intestinal mucosa mast cells were treated with flavonols followed by IgE-anti-dinitrophenyl sensitization. The extent of degranulation and the release of pro-inflammatory cytokines were measured. Caco-2 cells were stimulated with interleukin (IL)-4 or IgE-allergen with or without flavonol pretreatment and changes in the expression of CD23 mRNA and mitogen-activated protein kinase (MAPK), and chemokine release were determined.

Results

Flavonols inhibited the secretion of allergic mediators in RBL-2H3 cells and suppressed the CD23 mRNA expression and p38 MAPK activation in IL-4 stimulated Caco-2 cells. Flavonols also suppressed IgE-OVA induced extra signal-regulated protein kinase (ERK) activation and chemokine release.

Conclusions

Quercetin and kaempferol effectively suppressed the development of IgE-mediated allergic inflammation of intestinal cell models.     

Shigella flexneri enters human colonic Caco-2 epithelial cells through the basolateral pole.

The commonly accepted view that enteroinvasive bacteria enter cells of the intestinal epithelial lining through the apical surface can be challenged in the case of shigellosis. This study is based on in vitro experiments that showed that the invasion of human colonic Caco-2 cells by Shigella flexneri occurred through the basolateral pole of these cells. In these experiments, the few bacteria that interacted with the apical surface either bound to microvilli of the cell dome without causing detectable alteration or bound at the level of intercellular junctions at which they demonstrated a limited capacity for paracellular invasion, which permitted subsequent entry through the lateral domain of the cells. Treatment of Caco-2 cell monolayers with ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA), which disrupts intercellular junctions, greatly enhanced the rate of cell infection. These observations suggest a physiopathological paradox that may have important consequences for the understanding of the process of colonic invasion in vivo during shigellosis.     

Methanol extract of Phellodendri cortex alleviates lipopolysaccharide-induced acute airway inflammation in mice

Background and aim: The effects of methanol extract of Phellodendri cortex on acute airway inflammation induced by intranasal administration of lipopolysaccharide (LPS, 300μg/kg) were investigated in female BALB/c mice.

Materials and methods: At 2?h after LPS exposure, mice were treated orally with methanol extract of Phellodendri cortex (100, 200 and 400?mg/kg). At the end of this study, bronchoalveolar lavage fluids (BALF) were collected and number of total cells, macrophages and neutrophils, protein concentration were analyzed. Tumor necrosis factor-alpha (TNF-α), macrophage inflammatory protein (MIP-2), IL-10 levels and nitric oxide (NO) production in BALF were also determined.

Results: Methanol extract of Phellodendri cortex dose-dependently alleviated LPS-induced acute airway inflammation via decreasing the infiltration of inflammatory cells and the release of inflammatory mediators.

Conclusion: The relief of airway inflammation provides a possible therapeutic application of Phellodendri cortex for the treatment of infectious pulmonary diseases.     

Hydrogen-rich water partially alleviate inflammation,oxidative stress and intestinal flora dysbiosis in DSS-induced chronic ulcerative colitis mice

PurposeOxidative damage and intestinal flora dysbiosis play important roles in the progression of chronic ulcerative colitis (UC). This study explored the effect and mechanism of molecular hydrogen in chronic UC.Materials and methodsMale C57BL/6 mice (19.6 ?± ?0.4 ?g, 7 weeks) were randomly divided into 3 groups: normal control (NC) group, UC (Dextran Sulfate Sodium, DSS) group, and hydrogen-rich water (HRW, 0.8 ?ppm)-treated UC (DSS ?+ ?HRW) group. Mice in the DSS treatment group were treated with DSS for the following 3 cycles to establish chronic UC model: the first 2 cycles consisted of 2.5% DSS for 5 days, followed by drinking water for 16 days, and a third cycle consisted of 2% DSS for 4 days, followed by drinking water for 10 days. The mice in the DSS ?+ ?HRW group were administered HRW daily throughout the experiment.ResultsThe mice in the DSS groups developed typical clinical signs of colitis. HRW treatment partially ameliorated colitis symptoms, improved histopathological changes, significantly increased glutathione (GSH) concentration and decreased TNF-α level. Notably, HRW treatment significantly inhibited the growth of Enterococcus faecalis, Clostridium perfringens and Bacteroides fragilis (P ?< ?0.05 vs. DSS group), with the relative abundance that was close to the levels in the NC group. Microarray analysis revealed that 252 genes were significantly modified after HRW treatment compared with those in the DSS treatment alone group, and 17 genes were related to inflammation, including 9 interferon-stimulated genes (ISGs).ConclusionsHydrogen-rich water partially alleviates inflammation, oxidative stress and intestinal flora dysbiosis in DSS-induced chronic UC mice.     

Adiponectin and inflammation: consensus and controversy

Circulating levels of adiponectin decrease with increasing visceral obesity and are lower in patients with type 2 diabetes, the metabolic syndrome, and cardiovascular disease compared with controls matched by body mass index. Several reports demonstrated anti-inflammatory effects of adiponectin. Because increased adipose tissue is associated with low-grade chronic inflammation and proinflammatory factors inhibit adiponectin production, the current hypothesis states that chronic inflammation associated with visceral obesity inhibits production of adiponectin, perpetuating inflammation. The negative correlation between adiponectin and markers of inflammation in the aforementioned conditions supports this hypothesis. In contrast with disorders typically associated with excess adiposity and positive energy balance, adiponectin levels are elevated--rather than decreased--in classic chronic inflammatory/autoimmune diseases that are unrelated to increased adipose tissue, such as rheumatoid arthritis, SLE, inflammatory bowel disease, type 1 diabetes, and cystic fibrosis. In these patients, adiponectin levels positively--rather than negatively--correlate with inflammatory markers. Furthermore, proinflammatory effects of adiponectin have been reported in tissues such as joint synovium and colonic epithelium. Thus, adiponectin is regulated in the opposite direction and may exert differential functions in classic versus obesity-associated inflammatory conditions. This article discusses this apparent paradox and presents possible alternative and/or complementary explanations.     

Tamoxifen decreases renal inflammation and alleviates disease severity in autoimmune NZB/W F1 mice

It has been documented that sex hormone may play a role in the pathogenesis of murine lupus. To determine the effect of tamoxifen (TAM) on NZB/W F1 female mice, a total dose of 800 microg (22 mg/kg body weight) of TAM was administered subcutaneously every 2 weeks. The control mice were injected with peanut oil only. After treatment with TAM for 5 months, the mice were killed and immunological parameters were evaluated. The results suggest that NZB/W F1 mice treated with TAM had less severe proteinuria and increased survival rate compared to controls. Flow cytometric analysis of splenocytes revealed a significantly lower percentage of B cells and CD5+ B cells in the TAM-treated group. There was a significantly lower serum level of soluble tumour necrosis factor (TNF) receptor I and II molecules in the TAM-treated mice. Immunohistological study showed that control mice had severe immune complex deposition in the kidney. In contrast, TAM-treated mice had much less pathological change. In summary, this study demonstrated that TAM treatment might be able to alleviate the symptoms of lupus nephritis, influence B-cell count, modulate the expression of cytokine receptors and thereby subsequently affect immune function. Further studies to determine the cellular mechanisms in lupus nephritis may increase our understanding of this complex disease and provide additional targets for therapeutic intervention.     

巨噬细胞中钙调蛋白2的缺失可缓解小鼠炎症性关节炎

目的研究探讨抑制巨噬细胞中钙调蛋白2的表达治疗炎症性关节炎的作用和相关机制。方法取野生型小鼠(wild type,WT)和钙调蛋白2敲除(knock out, KO)小鼠构建胶原诱导炎症性关节炎模型(collagen induced arthritis,CIA),检测炎症相关因子TNF-α、IL-1β、IL-6和TGF-β的mRNA及蛋白表达变化、小鼠足趾肿胀容积变化以及炎症组织细胞大小和增殖变化。进一步在293T细胞中检测钙调蛋白2和CCL3(macrophage inflammatory protein 1-α, MIP-1α)的结合情况。在骨髓单核巨噬细胞(bone marrow macrophages,BMMs)细胞中转染钙调蛋白2过表达和抑制慢病毒,检测钙调蛋白2潜在下游CCL3的表达。最后,使用抑制钙调蛋白2的慢病毒进行炎症性关节炎小鼠的治疗作用探索,进行上述病理性检测。结果荧光定量PCR和免疫印迹实验显示,钙调蛋白2 KO小鼠关节炎组织炎症因子分泌明显降低;足趾肿胀容积明显减小;炎症组织细胞明显变大,细胞增殖明显增多。荧光素酶实验和染色质免疫共沉淀实验结果显示,钙调蛋白2...     

Increased lymphocyte trafficking to colonic microvessels is dependent on MAdCAM-1 and C-C chemokine mLARC/CCL20 in DSS-induced mice colitis

Although enhanced lymphocyte trafficking is associated with colitis formation, little information about its regulation is available. The aim of this study was to examine how the murine liver and activation-regulated chemokine (mLARC/CCL20) contributes to lymphocyte recruitment in concert with vascular adhesion molecules in murine chronic experimental colitis. T and B lymphocytes isolated from the spleen were fluorescence-labelled and administered to recipient mice. Lymphocyte adhesion to microvessels of the colonic mucosa and submucosa was observed with an intravital microscope. To induce colitis, the mice received two cycles of treatment with 2% dextran sodium sulphate (DSS). In some of the experiments antibodies against the adhesion molecules or anti-mLARC/CCL20 were administered, or CC chemokine receptor 6 (CCR6) of the lymphocytes was desensitized with excess amounts of mLARC/CCL20. Significant increases in T and B cell adhesion to the microvessels of the DSS-treated mucosa and submucosa were observed. In chronic colitis, the accumulation of lymphocytes was significantly inhibited by anti-mucosal addressin cell adhesion molecule (MAdCAM)-1 mAb, but not by anti-vascular cell adhesion molecule-1. In DSS-treated colonic tissue, the expression of mLARC/CCL20 was significantly increased, the blocking of mLARC/CCL20 by monoclonal antibody or the desensitization of CCR6 with mLARC/CCL20 significantly attenuated the DSS-induced T and B cell accumulation. However, the combination of blocking CCR6 with MAdCAM-1 did not further inhibit these accumulations. These results suggest that in chronic DSS-induced colitis, both MAdCAM-1 and mLARC/CCL20 may play important roles in T and B lymphocyte adhesion in the inflamed colon under flow conditions.     

Natural killer cells protect mice from DSS-induced colitis by regulating neutrophil function via the NKG2A receptor

Natural killer (NK) cells are traditionally considered in the context of tumor surveillance and infection defense but their role in chronic inflammatory disorders such as inflammatory bowel disease is less clear. Here, we investigated the role of NK cells in dextran sodium sulfate (DSS)-induced colitis in mice. Depletion of NK cells impairs the survival of mice with colitis and is linked with dramatic increases in colonic damage, leukocyte infiltration, and pro-inflammatory profiles. Mice depleted of NK cells had increased numbers of neutrophils in colons and mesenteric lymph nodes, compared with control mice, in addition to acquiring a hyper-activation status. In vitro and in vivo studies demonstrate that NK cells downregulate pro-inflammatory functions of activated neutrophils, including reactive oxygen species and cytokine production, by direct cell-to-cell contact involving the NK cell–inhibitory receptor NKG2A. Our results indicate an immunoregulatory mechanism of action of NK cells attenuating DSS-induced colitis neutrophil-mediated inflammation and tissue injury via NKG2A-dependent mechanisms.     

Inhibition of endoplasmic reticulum stress by 4-phenylbutyrate alleviates retinal inflammation and the apoptosis of retinal ganglion cells after ocular alkali burn in mice

Inflammation Research - Retinal ganglion cell (RGC) apoptosis is one of the most severe complications that causes permanent visual impairment following ocular alkali burn (OAB). Currently, very few...     

利用RNAi技术抑制结肠癌NRF2基因表达

目的构建RNA干扰真核表达载体pSUPER-NRF2,并在结肠癌细胞中进行表达,验证NRF2基因表达是否受到抑制。方法设计特异性针对NRF2基因的寡核苷酸序列及相应的对照序列,分别构建重组载体并转染人结肠癌Caco-2细胞。同时转染pEGFP-N1质粒,通过荧光显微镜观察及流式细胞仪检测绿色荧光来监测转染效率,共转染pEGFP-N1 48 h后G418筛选稳定表达的细胞。利用RT-PCR和W estern b lot检测瞬时及稳定转染细胞NRF2基因的表达。结果成功构建RNA i真核表达载体。转染pEGFP-N1后48 h达转染效率高峰。瞬时及稳定转染pSUPER-NRF2-A2、B2重组质粒NRF2 mRNA的表达无差异;转染48 h后,pSUPER-NRF2-A1、B1可显著抑制NRF2 mRNA的表达;pSUPER-NRF2-B1稳定转染后,NRF2 mRNA的表达也显著降低。瞬时和稳定筛选后NRF2蛋白表达亦显著降低。结论成功构建了NRF2的RNA i表达载体,可有效抑制靶基因表达,共转染带有筛选标记的pEGFP-N1质粒,筛选可获得低表达NRF2的稳定克隆,为进一步研究NRF2在结肠癌发生、发展中的作用提供了重要的实验材料。     

Autoimmune hepatic inflammation by vaccination of mice with dendritic cells loaded with well-differentiated hepatocellular carcinoma cells and administration of interleukin-12

Vaccination of mice with dendritic cells loaded with Hepa1-6, well-differentiated hepatocellular carcinoma cell line (DC/Hepa1-6), induced cytotoxic T lymphocytes against Hepa1-6. Liver-specific inflammation was generated by vaccination of mice with DC/Hepa1-6 and subsequent administration of interleukin (IL)-12. Vaccination with DCs loaded with MC38 or B16 and administration of IL-12 did not generate significant liver-specific inflammation. Splenic T cells from DC/Hepa1-6-vaccinated mice showed proliferative response by stimulation with S-100 protein of the liver and showed cytotoxic activity to hepatocytes. Hepatic mononuclear cells from DC/Hepa1-6 + IL-12-treated mice also showed cytotoxic activity to hepatocytes. Adoptive transfer of splenocytes from DC/Hepa1-6-vaccinated mice produced hepatic inflammation in recipient mice that had been pretreated with IL-12. IL-12 upregulated the expression of adhesion molecules and chemokines in the liver. In conclusion, CTLs responsive to hepatocytes induced by DC/Hepa1-6 and enhanced expression of adhesion molecules and chemokines in the liver by IL-12 would produce autoimmune hepatic inflammation.     

菠萝蛋白酶诱导小鼠急性过敏性气道炎症的作用研究

探讨菠萝蛋白酶诱导小鼠急性过敏性气道炎症中2型固有淋巴细胞(group 2innate lymphoid cell,ILC2)及相关细胞因子的变化及意义。对未致敏BALB/c雌性小鼠在第1天和第3天给予菠萝蛋白酶滴鼻,ELISA检测12h内小鼠肺组织匀浆上清中IL-33变化,5d后处死小鼠,肺组织切片病理观察,瑞氏染色计数BALF中嗜酸性粒细胞含量,流式检测肺组织中ILC2数量变化,ELISA检测BALF中IL-5、IL-13水平。结果显示,菠萝蛋白酶诱导气道上皮细胞产生IL-33,3h时开始,6h时达高峰;菠萝蛋白酶滴鼻小鼠肺组织切片显示大量炎性细胞浸润和杯状细胞黏液分泌增加,BALF中嗜酸性粒细胞比例增加,IL-5和IL-13含量增加,流式检测肺组织中ILC2数量增多。研究表明,菠萝蛋白酶刺激小鼠气道上皮细胞释放IL-33,引起小鼠肺ILC2活化增殖并分泌大量Th2型细胞因子,引起嗜酸性粒细胞浸润等急性过敏性气道炎症表现,提示ILC2促进早期急性过敏性气道炎症的发生。     

Spontaneous development of intestinal and colonic atrophy and inflammation in the carnitine-deficient jvs (OCTN2(-/-)) mice

Carnitine is essential for transport of long-chain fatty acids into mitochondria for their subsequent beta-oxidation, but its role in the gastrointestinal tract has not been well described. Recently several genetic epidemiologic studies have shown strong association between mutations in carnitine transporter genes OCTN1 and OCTN2 and a propensity to develop Crohn's disease. This study aims to investigate role of carnitine and beta-oxidation in the GI tract. We have studied the gastrointestinal tract effects of carnitine deficiency in a mouse model with loss-of-function mutation in the OCTN2 carnitine transporter. juvenile visceral steatosis (OCTN2(-/-)) mouse spontaneously develops intestinal villous atrophy, breakdown and inflammation with intense lymphocytic and macrophage infiltration, leading to ulcer formation and gut perforation. There is increased apoptosis of jvs (OCTN2(-/-)) gut epithelial cells. We observed an up-regulation of heat shock factor-1 (HSF-1) and several heat shock proteins (HSPs) which are known to regulate OCTN2 gene expression. Intestinal and colonic epithelial cells in wild type mice showed high expression and activity of the enzymes of beta-oxidation pathway. These studies provide evidence of an obligatory role for carnitine in the maintenance of normal intestinal and colonic structure and morphology. Fatty acid oxidation, a metabolic pathway regulated by carnitine-dependent entry of long-chain fatty acids into mitochondrial matrix, is likely essential for normal gut function. Our studies suggest that carnitine supplementation, as a means of boosting fatty acid oxidation, may be therapeutically beneficial in patients with inflammation of the intestinal tract.