18 research outputs found

    Increased levels of interleukin-6 exacerbate the dystrophic phenotype in mdx mice

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    Duchenne muscular dystrophy (DMD) is characterized by progressive lethal muscle degeneration and chronic inflammatory response. The mdx mouse strain has served as the animal model for human DMD. However, while DMD patients undergo extensive necrosis, the affected muscles of adult mdx mice rapidly regenerates and regains structural and functional integrity. The basis for the mild effects observed in mice compared with the lethal consequences in humans remains unknown. In this study, we provide evidence that interleukin-6 (IL-6) is causally linked to the pathogenesis of muscular dystrophy. We report that forced expression of IL-6, in the adult mdx mice, recapitulates the severe phenotypic characteristics of DMD in humans. Increased levels of IL-6 exacerbate the dystrophic muscle phenotype, sustaining inflammatory response and repeated cycles of muscle degeneration and regeneration, leading to exhaustion of satellite cells. The mdx/IL6 mouse closely approximates the human disease and more faithfully recapitulates the disease progression in humans. This study promises to significantly advance our understanding of the pathogenic mechanisms that lead to DMD

    Mouse Models for Epsin Function

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    The vertebrate skin is a barrier-forming organ in which keratinocytes form a highly organized, stratified epithelium protecting the organism from the outside environment. One of the major regulators of this structure is Notch signaling. Notch is a transmembrane receptor interacting with ligands expressed on the surface of neighboring keratinocytes. Keratinocyte-specific deletion of Notch signaling pathway impairs epidermal differentiation, resulting in skin-barrier defects and skin carcinogenesis. Our laboratory, by a genetic approach in mice, demonstrates that combined inactivation of Epsin1 and Epsin2 genes leads to embryonic lethality around E9.5-10. The phenotype of Epn1;Epn2 double knockout is characterized by a subversion of the three main developmental programs active at this developmental stage, i.e., cardiovascular development, somitogenesis, and neural tube differentiation. Collectively, these morphological alterations resemble the developmental defects observed in mutants of Notch genes or in genes essential for the activation of the Notch signaling pathway, suggesting a crucial role of Epsin in enabling Notch signaling during embryogenesis. Intriguingly, the apparently healthy Epn1+/-;Epn2-/- shows an high incidence of squamous papillomas on their skin. Furthermore, expression of another epsin family member originally localized exclusively to surface epithelia, Epsin3, dramatically increases in the hyperplastic lesions of the three-allele mutants and in human basal carcinomas. In order to get further insight on Epn3 function we performed morphological expression analyses during mouse development. In contrast with initial reports, both in embryos and adults, we could detect various levels of Epn3 expression in several tissues, i.e., surface epithelia, neural tissue and heart. Moreover, in vitro studies performed on human keratinocytes in culture show a prominent role of this Epsin in the regulation of Notch signaling in this cell compartment

    TCTN2:a novel tumor marker with oncogenic properties

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    Tectonic family member 2 (TCTN2) encodes a transmembrane protein that belongs to the tectonic family, which is involved in ciliary functions. Previous studies have demonstrated the role of tectonics in regulating a variety of signaling pathways at the transition zone of cilia. However, the role of tectonics in cancer is still unclear. Here we identify that TCTN2 is overexpressed in colorectal, lung and ovary cancers. We show that different cancer cell lines express the protein that localizes at the plasma membrane, facing the intracellular milieu. TCTN2 over-expression in cancer cells resulted in an increased ability to form colonies in an anchorage independent way. On the other hand, downregulation of TCTN2 using targeted epigenetic editing in cancer cells significantly reduced colony formation, cell invasiveness, increased apoptosis and impaired assembly of primary cilia. Taken together, our results indicate that TCTN2 acts as an oncogene, making it an interesting cancer-associated protein and a potential candidate for therapeutic applications.</p

    Potential advantages of cell administration on the inflammatory response compared to standard ACE inhibitor treatment in experimental myocardial infarction

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    <p>Abstract</p> <p>Background</p> <p>Bone Marrow (BM) progenitor cells can target the site of myocardial injury, contributing to tissue repair by neovascolarization and/or by a possible direct paracrine effect on the inflammatory cascade. Angiotensin Converting Enzyme inhibitors (ACE-I) are effective in reducing mortality and preventing left ventricular (LV) function deterioration after myocardial infarction.</p> <p>Methods</p> <p>We investigated the short term effects of BM mononuclear cells (BMMNCs) therapy on the pro-inflammatory cytokines (pro-CKs) and on LV remodelling and compared these effects over a standard ACE-I therapy in a rat model of myocardial cryodamage.</p> <p>Forty two adult inbread Fisher-F344 rats were randomized into three groups: untreated (UT; n = 12), pharmacological therapy (ACE-I; n = 14, receiving quinapril), and cellular therapy (BMMNCs; n = 16, receiving BMMNCs infusion). Rats underwent to a standard echocardiogram in the acute setting and 14 days after the damage, before the sacrifice. Pro-CKs analysis (interleukin (IL)1β, IL-6, tumor necrosis factor (TNF)α was performed (multiplex proteome arrays) on blood samples obtained by direct aorta puncture before the sacrifice; a control group of 6 rats was considered as reference.</p> <p>Results</p> <p>Concerning the extension of the infarcted area as well as the LV dimensions, no differences were observed among the animal groups; treated rats had lower left atrial diameters and higher indexes of LV function. Pro-Cks were increased in infarcted-UT rats if compared with controls, and significantly reduced by BMMNCs and ACE-I ; TNFα inversely correlated with LV fractional shortening.</p> <p>Conclusion</p> <p>After myocardial infarction, both BMMNCs and ACE-I reduce the pattern of pro-Ck response, probably contributing to prevent the deterioration of LV function observed in UT rats.</p

    A Hopf-Lax formula for Hamilton-Jacobi equations with Caputo time-fractional derivative

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    We prove a representation formula of Hopf-Lax type for solutions to Hamilton-Jacobi equation involving a Caputo time-fractional derivative. Equations of this type are associated with optimal control problems where the controlled dynamics is given by a time-changed stochastic process describing the trajectory of a particle subject to random trapping effects

    Granular cell tumor of the breast : molecular pathology and clinical management

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    Granular cell tumor is a rare condition that occasionally affects breast parenchyma: approximately, 5%-15% of all granular cell tumors represent 1:1000 of breast tumors. In this study, we reported a consecutive series of 12 patients with primary granular cell tumor of the breast observed at our institute, focusing attention on preoperative management, surgical approach, and long-term follow-up. Eight cases (8/12; 66.78%) presented with left-breast tumors; in the majority of patients (11/12; 91.7%), the lesion was identified in one of the upper quadrants. Specifically, upper intern quadrants (10 cases) were more affected. Surgical excision was performed in all patients. Mean diameter at pathologic section was 11.4 mm (range: 5-22). Tumor relapse was reported only in one case (8.3%). Mean follow-up was 98.1 months (range: 1-192). We proposed a model to explain the molecular mechanism of granular cell tumorigenesis associating to the high level of S100 protein. Management of primary granular cell tumor of the breast requires a correct initial diagnosis using breast imaging associated with core biopsy. Surgical procedure with wide resection or quadrantectomy requires a careful evaluation of breast margins
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