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  • 1.

    【2hr】Activation of Peroxisome Proliferator-Activated Receptor γ Contributes to the Survival of T Lymphoma Cells by Affecting Cellular Metabolism

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    机译 过氧化物酶体增殖物激活的受体γ的激活通过影响细胞代谢促进T淋巴瘤细胞的存活。
    摘要：Peroxisome proliferator-activated receptor γ (PPARγ) is a metabolic regulator involved in maintaining glucose and fatty acid homeostasis. Besides its metabolic functions, the receptor has also been implicated in tumorigenesis. Ligands of PPARγ induce apoptosis in several types of tumor cells, leading to the proposal that these ligands may be used as antineoplastic agents. However, apoptosis induction requires high doses of ligands, suggesting the effect may not be receptor-dependent. In this report, we show that PPARγ is expressed in human primary T-cell lymphoma tissues and activation of PPARγ with low doses of ligands protects lymphoma cells from serum starvation-induced apoptosis. The prosurvival effect of PPARγ was linked to its actions on cellular metabolic activities. In serum-deprived cells, PPARγ attenuated the decline in ATP, reduced mitochondrial hyperpolarization, and limited the amount of reactive oxygen species (ROS) in favor of cell survival. Moreover, PPARγ regulated ROS through coordinated transcriptional control of a set of proteins and enzymes involved in ROS metabolism. Our study identified cell survival promotion as a novel activity of PPARγ. These findings highlight the need for further investigation into the role of PPARγ in cancer before widespread use of its agonists as anticancer therapeutics.
  • 2.

    【2hr】Repression of Repulsive Guidance Molecule C during Inflammation Is Independent of Hfe and Involves Tumor Necrosis Factor-α

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    机译 炎症过程中排斥指导分子C的抑制与Hfe无关，并涉及肿瘤坏死因子-α
    摘要：Genetic iron overload, or hemochromatosis, can be caused by mutations in HFE, hemojuvelin, and hepcidin genes. Hepcidin, a negative regulator of intestinal iron absorption, is found to be inappropriately low in both patients and in animal models, indicating that proper control of basal hepcidin levels requires both hemojuvelin and HFE. In mice, repulsive guidance molecule c (Rgmc, the hemojuvelin mouse ortholog) and hepcidin levels are transcriptionally regulated during inflammation. Here, we report that basal Rgmc levels in Hfe-deficient mice are normal and that these mice retain the ability to suppress Rgmc expression after lipopolysaccharide (LPS) challenge. Thus, Rgmc regulation by LPS is Hfe-independent. The response of Rgmc to LPS involves signaling through toll-like receptor 4 (Tlr4), because Tlr4-deficient mice do not show altered Rgmc expression after LPS administration. We further show that tumor necrosis factor-α, but not interleukin-6, is sufficient to cause Rgmc down-regulation by LPS. These results contrast with previous data demonstrating that hepcidin levels are directly regulated by interleukin-6 but not by tumor necrosis factor-α. The regulation of iron-related genes by different cytokines may allow for time-dependent control of iron metabolism changes during inflammation and may be relevant to chronic inflammation, infections, and cancer settings, leading to the development of anemia of chronic disease.
  • 3.

    【2hr】Oxidative Phenotype Protects Myofibers from Pathological Insults Induced by Chronic Heart Failure in Mice

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    机译 氧化表型可以保护肌纤维免受小鼠慢性心力衰竭引起的病理损伤
    摘要：The fiber specificity of skeletal muscle abnormalities in chronic heart failure (CHF) has not been defined. We show here that transgenic mice (8 weeks old) with cardiac-specific overexpression of calsequestrin developed CHF (50.9% decrease in fractional shortening and 56.4% increase in lung weight, P < 0.001), cachexia (37.8% decrease in body weight, P < 0.001), and exercise intolerance (69.3% decrease in running distance to exhaustion, P < 0.001) without a significant change in muscle fiber-type composition. Slow oxidative soleus muscle maintained muscle mass, whereas fast glycolytic tibialis anterior and plantaris muscles underwent atrophy (11.6 and 13.3%, respectively; P < 0.05). In plantaris muscle, glycolytic type IId/x and IIb, but not oxidative type I and IIa, fibers displayed significant decreases in cross-sectional area (20.3%, P < 0.05). Fast glycolytic white vastus lateralis muscle showed sarcomere degeneration and decreased cytochrome c oxidase IV (39.5%, P < 0.01) and peroxisome proliferator-activated receptor γ co-activator 1α protein expression (30.3%, P < 0.01) along with a dramatic induction of the MAFbx/Atrogin-1 mRNA. These findings suggest that exercise intolerance can occur in CHF without fiber type switching in skeletal muscle and that oxidative phenotype renders myofibers resistant to pathological insults induced by CHF.
  • 4.

    【2hr】Aberrant Expression of Leptin in Human Endometriotic Stromal Cells Is Induced by Elevated Levels of Hypoxia Inducible Factor-1α

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    机译 缺氧诱导因子-1α水平升高诱导子宫内膜异位症基质细胞中瘦素的异常表达。
    摘要：Elevated expression of leptin in endometriotic tissue results in an increase in stromal cell proliferation and may contribute to the development of endometriosis. However, the underlying mechanism responsible for aberrant expression of leptin is not known. We hypothesize that aberrant expression of leptin in endometriotic stroma may be regulated by increased levels of hypoxia-inducible factor-1α (HIF-1α), the master transcription factor that controls gene expression in response to hypoxia. Herein we show that the mRNA and protein levels of HIF-1α were greater in ectopic endometriotic tissue compared with its eutopic counterpart. Exposure of eutopic endometrial stromal cells under hypoxic conditions or treated with desferrioxamine (DFO, chemical hypoxia) resulted in a time-dependent increase in leptin gene expression. A promoter activity assay demonstrated that HIF-1α induced leptin promoter activity after DFO treatment. Chromatin immunoprecipitation assay further demonstrated that binding of HIF-1α to leptin promoter was evident after DFO treatment. Finally, depletion of HIF-1α by short interference RNA abolished leptin expression in ectopic endometriotic stromal cells. Taken together, our data demonstrate that aberrant expression of leptin in ectopic endometriotic stromal cells is induced, at least in part, by an elevated level of HIF-1α in these cells, providing new insights into the etiology of endometriosis.
  • 5.

    【2hr】CXCL1/KC and CXCL2/MIP-2 Are Critical Effectors and Potential Targets for Therapy of Escherichia coli O157:H7-Associated Renal Inflammation

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    机译 CXCL1 / KC和CXCL2 / MIP-2是治疗大肠杆菌O157：H7相关性肾炎的关键效应物和潜在靶标
    摘要：Neutrophilia is a characteristic of hemolytic uremic syndrome caused by Shiga toxin (Stx2)-producing Escherichia coli. However, the role of neutrophils in the toxin-induced renal injury occurring in enterohemorrhagic E. coli infection remains undefined. We report the trafficking of neutrophils to the kidney of C57BL/6 mice throughout a 72-hour time course after challenge with purified E. coli Stx2 and lipopolysaccharide (LPS). Increased neutrophils were observed in the renal cortex, particularly within the glomeruli where a more than fourfold increase in neutrophils was noted within 2 hours after challenge. Using microarray analysis, an increased number of transcripts for chemoattractants CXCL1/KC (69-fold at 2 hours) and CXCL2/MIP-2 (29-fold at 2 hours) were detected. Ribonuclease protection assays, Northern blotting, enzyme-linked immunosorbent assay, and immunohistochemistry confirmed microarray results, showing that both chemokines were expressed only on the immediate periglomerular epithelium and that these events coincided with neutrophil invasion of glomeruli. Co-administration of Stx2 with LPS enhanced and prolonged the KC and MIP-2 host response (RNA and protein) induced by LPS alone. Immunoneutralization in vivo of CXCL1/KC and CXCL2/MIP-2 abrogated neutrophil migration into glomeruli by 85%. These data define the molecular basis for neutrophil migration into the kidney after exposure to virulence factors of Shiga toxin-producing E. coli O157:H7.
  • 6.

    【2hr】Permselective Dysfunction of Podocyte-Podocyte Contact upon Angiotensin II Unravels the Molecular Target for Renoprotective Intervention

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    机译 血管紧张素II的足细胞-足细胞接触的选择性渗透功能异常揭示了肾脏保护性干预的分子靶标。
    摘要：Ameliorating the function of the glomerular barrier to circulating proteins by blocking angiotensin II (Ang II) translates into less risk of progression toward end-stage renal failure in diabetic and nondiabetic nephropathies. However, the mechanisms underlying this barrier protection are not clear. Specialized contacts between adjacent podocytes are major candidate targets, and the actin cytoskeleton is emerging as a regulatory element. Here, we present data demonstrating that Ang II induced reorganization of F-actin fibers and redistribution of zonula occludens-1 (ZO-1) that is physically associated with actin in murine podocytes. These effects were paralleled by increased albumin permeability across podocyte monolayers. The F-actin stabilizer jasplakinolide prevented both ZO-1 redistribution and albumin leakage, suggesting that actin cytoskeleton rearrangement is instrumental to podocyte permselective dysfunction induced by Ang II. Changes in both F-actin and ZO-1 patterns were confirmed in glomeruli of rat isolated perfused kidneys on short infusion of Ang II, leading to increased protein excretion. Podocyte dysfunction was mediated by Ang II type 1 receptor and was partly dependent on Src kinase-phospholipase C activation. These data demonstrate that strategies aimed at stabilizing podocyte-podocyte contacts and targeting the relevant intracellular signal transduction are crucial to renoprotection.
  • 7.

    【2hr】Thrombin-Activatable Fibrinolysis Inhibitor Deficiency Attenuates Bleomycin-Induced Lung Fibrosis

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    机译 凝血酶激活的纤溶抑制剂缺乏会减弱博来霉素诱导的肺纤维化。
    摘要：Decreased fibrinolytic function favors the development of pulmonary fibrosis. Thrombin-activatable fibrinolysis inhibitor (TAFI) is a strong suppressor of fibrinolysis, but its role in lung fibrosis is unknown. Therefore, we compared bleomycin-induced lung fibrosis in TAFI-deficient, heterozygous, and wild-type mice. The animals were sacrificed 21 days after bleomycin administration, and markers of lung fibrosis and inflammation were measured. The bronchoalveolar lavage fluid levels of total protein, neutrophil proteases (elastase, myeloperoxidase), cytokines (tumor necrosis factor-α, interleukin-13), chemokine (monocyte chemoattractant protein-1), coagulation activation marker (thrombin-antithrombin complex), total soluble collagen, and growth factors (platelet-derived growth factor, transforming growth factor-β1, granulocytic-macrophage growth factor) were significantly decreased in knockout mice compared to wild-type mice. Further, histological findings of fibrosis, fibrin deposition, and hydroxyproline and collagen content in the lung were significantly decreased in knockout mice compared to wild-type mice. Depletion of fibrinogen by ancrod treatment led to equalization in the amount of fibrosis and collagen deposition in the lungs of knockout and wild-type mice. No difference was detected in body temperature or arterial pressure between the different mouse phenotypes. These results suggest that the anti-fibrinolytic activity of TAFI promotes lung fibrosis by hindering the rate at which fibrin is degraded.
  • 8.

    【2hr】Elevated Levels of Cholesterol-Rich Lipid Rafts in Cancer Cells Are Correlated with Apoptosis Sensitivity Induced by Cholesterol-Depleting Agents

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    机译 癌细胞中胆固醇丰富的脂质筏的升高水平与胆固醇消耗剂诱导的细胞凋亡敏感性相关
    摘要：Lipid rafts/caveolae are membrane platforms for signaling molecules that regulate various cellular functions, including cell survival. To better understand the role of rafts in tumor progression and therapeutics, we investigated the effect of raft disruption on cell viability and compared raft levels in human cancer cell lines versus their normal counterparts. Here, we report that cholesterol depletion using methyl-β cyclodextrin caused anoikis-like apoptosis, which in A431 cells involved decreased raft levels, Bcl-xL down-regulation, caspase-3 activation, and Akt inactivation regardless of epidermal growth factor receptor activation. Cholesterol repletion replenished rafts on the cell surface and restored Akt activation and cell viability. Moreover, the breast cancer and the prostate cancer cell lines contained more lipid rafts and were more sensitive to cholesterol depletion-induced cell death than their normal counterparts. These results indicate that cancer cells contain increased levels of rafts and suggest a potential use of raft-modulating agents as anti-cancer drugs.
  • 9.

    【2hr】Peroxisomal Multifunctional Protein-2 Deficiency Causes Motor Deficits and Glial Lesions in the Adult Central Nervous System

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    机译 过氧化物酶体多功能蛋白2缺乏症导致成人中枢神经系统运动功能障碍和神经胶质病变。
    摘要：In humans, mutations inactivating multifunctional protein-2 (MFP-2), and thus peroxisomal β-oxidation, cause neuronal heterotopia and demyelination, which is clinically reflected by hypotonia, seizures, and death within the first year of life. In contrast, our recently generated MFP-2-deficient mice did not show neurodevelopmental abnormalities but exhibited aberrations in bile acid metabolism and one of three of them died early postnatally. In the postweaning period, all survivors developed progressive motor deficits, including abnormal cramping reflexes of the limbs and loss of mobility, with death at 6 months. Motor impairment was not accompanied by lesions of peripheral nerves or muscles. However, in the central nervous system MFP-2-deficient mice overexpressed catalase in glial cells, accumulated lipids in ependymal cells and in the molecular layer of the cerebellum, exhibited severe astrogliosis and reactive microglia predominantly within the gray matter of the brain and the spinal cord, whereas synaptic and myelin markers were not affected. This culminated in degenerative changes of astroglia cells but not in overt neuronal lesions. Neither the motor deficits nor the brain lesions were aggravated by increasing the branched-chain fatty acid concentration through dietary supplementation. These data indicate that MFP-2 deficiency in mice causes a neurological phenotype in adulthood that is manifested primarily by astroglial damage.
  • 10.

    【2hr】Alcohol Abuse Enhances Neuroinflammation and Impairs Immune Responses in an Animal Model of Human Immunodeficiency Virus-1 Encephalitis

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    机译 在人类免疫缺陷病毒-1脑炎的动物模型中，酗酒会增强神经炎症并损害免疫反应。
    摘要：Neuroinflammatory disorders (including human immunodeficiency virus-1 encephalitis, HIVE) are associated with oxidative stress and inflammatory brain injury, and excessive alcohol use can exacerbate tissue damage. Using a murine model of HIVE, we investigated the effects of alcohol abuse on the clearance of virus-infected macrophages and neuroinflammation. Severe combined immunodeficient mice were reconstituted with human lymphocytes, and encephalitis was induced by intracranial injection of HIV-1-infected monocyte-derived macrophages (HIV-1+ MDM). Animals were fed an ethanol-containing diet beginning 2 weeks before lymphocyte engraftment and for the entire duration of the experiment. Lymphocyte engraftment was not altered by ethanol exposure. Alcohol-mediated immunosuppression in ethanol-fed mice was manifested by a significant decrease in CD8+/interferon-γ+ T lymphocytes, a fivefold increase in viremia, and diminished expression of immunoproteasomes in the spleen. Although both groups showed similar amounts of CD8+ T-lymphocyte infiltration in brain areas containing HIV-1+ MDMs, ethanol-fed mice featured double the amounts of HIV-1+ MDMs in the brain compared to controls. Ethanol-exposed mice demonstrated higher microglial reaction and enhanced oxidative stress. Alcohol exposure impaired immune responses (increased viremia, decreased immunoproteasome levels, and prevented efficient elimination of HIV-1+ MDMs) and enhanced neuroinflammation in HIVE mice. Thus, alcohol abuse could be a co-factor in progression of HIV-1 infection of the brain.
  • 11.

    【2hr】Possible Regulation of Migration of Intrahepatic Cholangiocarcinoma Cells by Interaction of CXCR4 Expressed in Carcinoma Cells with Tumor Necrosis Factor-α and Stromal-Derived Factor-1 Released in Stroma

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    机译 癌细胞中表达的CXCR4与基质中释放的肿瘤坏死因子-α和基质衍生因子-1的相互作用可能调节肝内胆管癌细胞的迁移。
    摘要：Intrahepatic cholangiocarcinoma (ICC) is highly fatal because of early invasion, widespread metastasis, and lack of an effective therapy. We examined roles of CXCR4 and its ligand, stromal cell-derived factor (SDF)-1, in migration of ICC with respect to tumor-stromal interaction by using two ICC cell lines, a fibroblast cell line (WI-38), and 28 human ICC tissues. The two ICC cell lines expressed CXCR4 mRNA and protein, and WI-38 fibroblasts expressed SDF-1 mRNA and protein. Migration of cultured ICC cells in Matrigel was induced by co-culture with WI-38 fibroblasts and by incubation with SDF-1. Anti-SDF-1 antibody suppressed migration, demonstrating that SDF-1 released from WI-38 fibroblasts was responsible for this migration. Tumor necrosis factor (TNF)-α pretreatment of ICC cells up-regulated CXCR4 mRNA and protein expression in a concentration-dependent manner. Administration of SDF-1 and TNF-α increased synergistically ICC cell migration, which was suppressed by the CXCR4 antagonist AMD3100. In ICC tissue, TNF-α was mainly expressed in infiltrated macrophages, CXCR4 in ICC cells, and SDF-1 in stromal fibroblasts. In conclusion, the interaction of SDF-1 released from fibroblasts and CXCR4 expressed on ICC cells may be actively involved in ICC migration, and TNF-α may enhance ICC cell migration by increasing CXCR4 expression. CXCR4 could be a therapeutic target to prevent ICC invasion.
  • 12.

    【2hr】The RetC620R Mutation Affects Renal and Enteric Development in a Mouse Model of Hirschsprung’s Disease

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    机译 RetC620R突变影响先天性疾病小鼠模型的肾脏和肠道发育
    摘要：In rare families RET tyrosine kinase receptor substitutions located in exon 10 (especially at positions 609, 618, and 620) can concomitantly cause the MEN 2A (multiple endocrine neoplasia type 2A) or FMTC (familial medullary thyroid carcinoma) cancer syndromes, and Hirschsprung’s disease (HSCR). No animal model mimicking the co-existence of the MEN 2 pathology and HSCR is available, and the association of these activating mutations with a developmental defect still represents an unresolved problem. The aim of this work was to investigate the significance of the RETC620R substitution in the pathogenesis of both gain- and loss-of-function RET-associated diseases. We report the generation of a line of mice carrying the C620R mutation in the Ret gene. Although RetC620R homozygotes display severe defects in kidney organogenesis and enteric nervous system development leading to perinatal lethality. RetC620R heterozygotes recapitulate features characteristic of HSCR including hypoganglionosis of the gastrointestinal tract. Surprisingly, heterozygotes do not show any defects in the thyroid that might be attributable to a gain-of-function mutation. The RetC620R allele is responsible for HSCR and affects the development of kidneys and the enteric nervous system (ENS). These mice represent an interesting model for studying new therapeutic approaches for the treatment of HSCR disease.
  • 13.

    【2hr】Maintenance of Bad Phosphorylation Prevents Apoptosis of Rat Hepatic Sinusoidal Endothelial Cells in Vitro and in Vivo

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    机译 维持不良磷酸化可防止大鼠肝窦和肝窦内皮细胞凋亡。
    摘要：To elucidate the mechanism of apoptosis of liver sinusoidal endothelial cells (SECs), we examined the phosphorylation status of Bad and its upstream signaling molecules during apoptosis in culture and after ischemia-reperfusion injury. Rat SECs were isolated by the immunomagnetic method, and 2 days after culture, most SECs underwent apoptosis, which was associated with decreased tyrosine phosphorylation of cellular proteins. Addition of orthovanadate (OV), a protein tyrosine phosphatase inhibitor, sustained cellular protein phosphorylation and strongly inhibited apoptosis. Bad was dephosphorylated at Ser-112 and Ser-136 during apoptosis, but the phosphorylation status of Bad was maintained in the presence of OV. OV activated the Akt, extracellular signal-regulated protein kinase, and p38 mitogen-activated protein kinase pathways, which are involved in Bad phosphorylation. In the absence of OV, depletion of Bad by RNA interference conferred resistance to apoptosis. Hepatic injury after ischemia-reperfusion was alleviated by OV treatment, with significant inhibition of SEC apoptosis. SEC apoptosis in vivo was associated with dephosphorylation of Bad, Akt, and extracellular signal-regulated protein kinase, which was blocked by OV treatment. Our data suggest that maintenance of Bad phosphorylation is important in the prevention of SEC apoptosis and that the anti-apoptotic property of OV might have therapeutic utility.
  • 14.

    【2hr】Lipoxin A4 Regulates Bronchial Epithelial Cell Responses to Acid Injury

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    机译 脂蛋白A4调节对酸损伤的支气管上皮细胞反应
    摘要：Aspiration of gastric acid commonly injures airway epithelium and, if severe, can lead to respiratory failure from acute respiratory distress syndrome. Recently, we identified cyclooxygenase-2 (COX-2)-derived prostaglandin E2 (PGE2) and lipoxin A4 (LXA4) as pivotal mediators in vivo for resolution of acid-initiated acute lung injury. To examine protective mechanisms for these mediators in the airway, we developed an in vitro model of acid injury by transiently exposing well-differentiated normal human bronchial epithelial cells to hydrochloric acid. Transmission electron microscopy revealed selective injury to superficial epithelial cells with disruption of cell attachments and cell shedding. The morphological features of injury were substantially resolved within 6 hours. Acid triggered and early marked increases in COX-2 expression and PGE2 production, and acid-induced PGE2 significantly increased epithelial LXA4 receptor (ALX) expression. LXA4 is generated in vivo during acute lung injury, and we observed that nanomolar quantities increased basal epithelial cell proliferation and potently blocked acid-triggered interleukin-6 release and neutrophil transmigration across well-differentiated normal human bronchial epithelial cells. Expression of recombinant human ALX in A549 airway epithelial cells uncovered ALX-dependent inhibition of cytokine release by LXA4. Together, these findings indicate that injured bronchial epithelial cells up-regulate ALX in a COX-2-dependent manner to promote LXA4-mediated resolution of airway inflammation.
  • 15.

    【2hr】Deficiency of C4 from Donor or Recipient Mouse Fails to Prevent Renal Allograft Rejection

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    机译 供体或受体小鼠的C4缺乏未能阻止同种异体肾的排斥反应
    摘要：Complement effector products generated in the transplanted kidney are known to mediate transplant rejection, but which of the three main activation pathways of complement trigger this response is unclear. Here we assessed the role of the classical and lectin pathways by studying the common component C4 in mouse kidney transplant rejection. We transplanted wild-type or C4-null H-2b donor kidneys into H-2k or H-2d recipients, or vice-versa, to assess the roles of donor kidney and recipient expression of complement. Intragraft C4 gene expression rose substantially during rejection. However, we found no significant association between graft acceptance and the presence of C4 in either the donor kidney or recipient mouse. At the time of rejection, we found no significant differences in alloantibody response in the different groups. Tubular deposition of C3 to C9 occurred regardless of the absence or presence of C4 in either the donor or recipient mouse, indicating that C4 was dispensable for complement activation at this site. These data suggest that complement activation and renal allograft rejection are independent of the classical and lectin pathways in these models, implying that in the absence of these pathways the alternative pathway is the main trigger for complement-mediated rejection.
  • 16.

    【2hr】Impairment of the Intestinal Barrier by Ethanol Involves Enteric Microflora and Mast Cell Activation in Rodents

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    机译 乙醇对肠道屏障的损害涉及啮齿类动物的肠道菌群和肥大细胞活化。
    摘要：Alcohol hepatic toxicity in heavy drinkers is associated with high endotoxin blood levels and increased intestinal permeability. Because endotoxins can cross damaged mucosa, we investigated the mechanisms through which ethanol impairs the colonic epithelium of rats submitted to acute alcohol intake. Colonic permeability to 51Cr-ethylenediamintetraacetic acid was increased 24 hours after 3.0 g/kg ethanol intake (3.2 ± 0.2% versus 2.2 ± 0.2%) and was associated with significant endotoxemia. Antibiotics and doxantrazole (a mast cell membrane stabilizer) significantly inhibited the effect of ethanol. Two hours after intake, plasma concentrations of ethanol were twofold higher in antibiotic-treated rats than in controls (155.8 ± 9.3 mg/dl versus 75.7 ± 7.6 mg/dl, P < 0.001). Lumenal concentrations of acetaldehyde were markedly increased after ethanol intake (132.6 ± 31.6 μmol/L versus 20.8 ± 1.4 μmol/L, P < 0.05) and antibiotics diminished this increase (86.2 ± 10.9 μmol/L). In colonic samples mounted in Ussing chambers, acetaldehyde but not ethanol increased dextran flux across the mucosa by 54%. Doxantrazole inhibited the effect of acetaldehyde. This study demonstrates that an acute and moderate ethanol intake alters the epithelial barrier through ethanol oxidation into acetaldehyde by the colonic microflora and downstream mast cell activation. Such alterations that remain for longer periods could result in excessive endotoxin passage, which could explain the subsequent endotoxemia frequently observed in patients with alcoholic liver disease.
  • 17.

    【2hr】Aquaporin 1 Is Overexpressed in Lung Cancer and Stimulates NIH-3T3 Cell Proliferation and Anchorage-Independent Growth

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    机译 水通道蛋白1在肺癌中过表达并刺激NIH-3T3细胞增殖和锚定非依赖性生长
    摘要：The aquaporins represent a family of transmembrane water channel proteins that play a major role in trans-cellular and transepithelial water movement. Most tumors have been shown to exhibit high vascular permeability and interstitial fluid pressure, but the transport pathways for water within tumors remain unknown. Here, we tested 10 non-small cell lung cancer cell lines of various origins by reverse transcriptase-polymerase chain reaction and Western blot analysis and identified clear expression of aquaporin 1 (AQP1) in seven cell lines. We next examined the distribution of the AQP1 protein in several types of primary lung tumors (16 squamous cell carcinomas, 21 adenocarcinomas, and 7 bronchoalveolar carcinomas) by immunohistochemical staining. AQP1 was overexpressed in 62% (13 of 21) and 75% (6 of 8) of adenocarcinoma and bronchoalveolar carcinoma, respectively, whereas all cases of squamous cell carcinoma and normal lung tissue were negative. Forced expression of full-length AQP1 cDNA in NIH-3T3 cells induced many phenotypic changes characteristic of transformation, including cell proliferation-enhancing activity by the MTT assay and anchorage-independent growth in soft agar. Although further details on the molecular function of AQP1 related to tumorigenesis remain to be elucidated, our results suggest a potential role of AQP1 as a novel therapeutic target for the management of lung cancer.
  • 18.

    【2hr】Generalized Lysosome-Associated Membrane Protein-2 Defect Explains Multisystem Clinical Involvement and Allows Leukocyte Diagnostic Screening in Danon Disease

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    机译 广义的溶酶体相关膜蛋白2缺陷说明多系统临床参与，并允许白细胞诊断筛查达农疾病。
    摘要：Danon disease, an X-linked dominant disorder, results from mutations in the lysosome-associated membrane protein-2 (LAMP2) gene and presents with hypertrophic cardiomyopathy, skeletal myopathy, and mental retardation. To investigate the effects of LAMP2 gene mutations on protein expression in different tissues, we screened LAMP2 gene mutations and LAMP-2 protein deficiency in the skeletal muscle of nine unrelated patients with hypertrophic cardiomyopathy and vacuolar myopathy. We identified three novel families (including one affected mother) with unreported LAMP2 gene null mutations and LAMP-2 protein deficiency in skeletal and myocardial muscle, leukocytes, and fibroblasts. LAMP-2 protein deficiency was detectable in various tissues, including leukocytes, explaining themultisystem clinical involvement. Skeletal muscle immunopathology showed that mutant protein was not localized in the Golgi complex, vacuolar membranes expressed sarcolemmal-specific proteins, and the degree of muscle fiber vacuolization correlated with clinical muscle involvement. In our female patient, muscle histopatholoy and LAMP-2 protein analysis was inconclusive, indicating that diagnosis in females requires mutation identification. The random X-chromosome inactivation found in muscle and leukocytes excluded the possibility that selective involvement of some tissues in females is due to skewed X-chromosome inactivation. Therefore, biochemical analysis of leukocytes might be used for screening in male patients, but genetic screening is required in females.
  • 19.

    【2hr】Therapeutic Effect of Vasoactive Intestinal Peptide on Experimental Autoimmune Encephalomyelitis

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    机译 血管活性肠肽对实验性自身免疫性脑脊髓炎的治疗作用
    摘要：Multiple sclerosis (MS) is a disabling inflammatory, autoimmune demyelinating disease of the central nervous system. Despite intensive investigation, the mechanisms of disease pathogenesis remain unclear, and curative therapies are unavailable for MS. The current study describes a possible new strategy for the treatment of MS, based on the administration of the vasoactive intestinal peptide (VIP), a well-known immunosuppressive neuropeptide. Treatment with VIP significantly reduced incidence and severity of experimental autoimmune encephalomyelitis (EAE), in a MS-related rodent model system. VIP suppressed EAE neuropathology by reducing central nervous system inflammation, including the regulation of a wide spectrum of inflammatory mediators, and by selectively blocking encephalitogenic T-cell reactivity. Importantly, VIP treatment was therapeutically effective in established EAE and prevented the recurrence of the disease. Consequently, VIP represents a novel multistep therapeutic approach for the future treatment of human MS.
  • 20.

    【2hr】Epigenetic Instability and Chromosomal Instability in Hepatocellular Carcinoma

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    机译 肝细胞癌的表观遗传不稳定性和染色体不稳定性
    摘要：The aim of this study was to clarify the association between the epigenetic instability phenotype and the chromosomal instability phenotype in primary hepatocellular carcinoma (HCC). Sixty primary HCC tumors were examined. Methylation status for nine CpG islands (the p16, COX2, GSTP1, RASSF1A, E-cadherin, and APC gene promoters, and the MINT 1, 25, and 31 clones) was evaluated by methylation-specific polymerase chain reaction. Chromosomal structural alterations of these 60 HCC tumors were characterized in our previous study by using whole genomic array-based comparative genomic hybridization. We found that the epigenetic instability phenotype and the chromosomal instability phenotype are not mutually exclusive in hepatocarcinogenesis and that they do not show a simple cause-and-effect relationship. Hepatitis virus infection in the background liver was significantly associated with these instability phenotypes. Furthermore, we identified an epigenetic instability-dependent HCC that shows frequent epigenetic aberrations without chromosomal instability. It was noteworthy that epigenetic instability-positive and -negative HCCs displayed distinctive combinations of chromosomal structural alterations. In summary, by combined analyses of genetic and epigenetic aberration profiles in HCC, we obtained a comprehensive view of genomic alterations in hepatocarcinogenesis. Our results have clinical relevance because epigenetic instability-dependent HCCs may respond well to methylation inhibitory therapies.
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