132 research outputs found

    Fibrosis: a role for vitamin D

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    Chronic inflammation leads to fibrosis and eventually organ failure. Fibrosis is defined as a wound-healing response that has gone awry. It is featured by excessive production, deposition, and accumulation of extracellular matrix components. The key mediator cells of fibrotic disorders are the myofibroblasts, derived from different precursor cells. Myofibroblasts are responsible of stiff ECM, a hallmark of fibrosis. It is mandatory understanding the molecular pathways contributing to develop the fibrotic tissue to discovery anti-fibrotic therapies. Vitamin D, the precursor of seco-steroid hormone, appears to have anti-fibrotic properties. Vitamin D deficiency may contribute to development of different fibrotic disorders in several organs. It counteracts the pro-fibrotic signals, such as TGF-β1, through several biochemical mechanisms. Counteracting TGF-β1, Vitamin D inhibits myofibroblasts activation and ECM deposition

    Growth factors and experimental arterial grafts

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    Background: The production of growth factors from several experimental arterial conduits was determined. Methods: We implanted 105 experimental arterial grafts that were 1 cm long in the abdominal aorta of Lewis rats (average weight, 250 g). Five different types of grafts were analyzed: arterial isografts, vein grafts, arterial allografts, and polytetrafluoroethylene (PTFE) grafts with normal or decreased compliance. Animals were killed humanely 4 weeks after surgery and the production of platelet-derived growth factor (PDGF), basic fibroblast growth factor (bFGF), transforming growth factor-b, tumor necrosis factor-a, and interleukin-1 was analyzed. Results: Myointimal hyperplasia (MH) was evident in vein grafts, arterial allografts, and PTFE grafts, but not in arterial isografts. Growth factor production was increased for grafts prone to develop MH like vein, PTFE grafts, and arterial allografts. PDGF and bFGF were increased significantly for PTFE and vein grafts, but not for arterial allografts. The importance of bFGF and PGDF was confirmed by the capability of antibody to PDGF and to bFGF to reduce the mitogenic activity of smooth muscle cells, in vivo and in vitro, for PTFE and vein grafts, but not for arterial allografts, in which a predominant role was played by interleukin-1 and tumor necrosis factor-a. Conclusions: Agents able to neutralize this increased production of growth factors, either directly or by competition with their receptors, can prevent MH formation. (J Vasc Surg 2016;64:1444-9.) Clinical Relevance: Arterial grafts release growth factors, which can lead to myointimal hyperplasia formation and atherosclerosis progression in the arterial tree. Both phenomena can cause graft occlusion. Inhibition of growth factor release by arterial grafts can improve their clinical effectiveness

    Gravity constraint in cell phenotypic determination

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    Distinct phenotypes emerge spontaneously when mammalian cells are cultured under microgravity conditions. Such finding is explained by the interplay among the intrinsic stochasticity, which, in turn, is successively ‘canalized’ and sustained by the activation of a specific gene regulatory network. However, when the two cell subsets are reseeded into a normal gravity field the two phenotypes collapse into one. Gravity constraints the system in adopting only one phenotype. Cell fate commitment is achieved through a de novo reshaping of the overall cell morphological and functional organization, and cannot be explained as a ‘selecting’ effect. Those findings highlight how constraints – acting as global order factors – drive cell specification and behavior. These data cast on doubt the current explanatory bottom-up, molecular based models

    Journey to Mars. A Biomedical Challenge. Perspective on future human space flight

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    Manned space flight has been the greatest human and technological adventure of the past half-century. Putting people into places and situations unprecedented in history is stirred the imagination while the human experience was expanding and redefining. Yet, space exploration compels humans to confront a hostile environment of cosmic radiations, radical changes in the gravity and magnetic fields, as well as social isolation. Therefore, any space traveller is submitted to relevant health-related threats. In the twenty-first century, human space flight is poised to continue, but it will enjoy the ongoing developments in science and technology. It will become more networked, more global, and more oriented toward primary goals. A novel international human space flight policy could help achieve these objectives by clarifying the rationale, the ethics of acceptable risk, the role of remote presence, and the need for balance between funding and ambition to justify the risk of human lives. In order to address such a challenge, a preliminary careful survey of the available scientific data is mandatory to set forth adequate countermeasures. Envisaged solutions should provide a sound and technically feasible approach for counteracting microgravity and cosmic rays effects, which represent the main health risk for space crews. This objective must necessarily be sustained by national/international space agencies, which would coordinate their common efforts into a defined international spaceflight program

    An association of boswellia, betaine and myo-inositol (Eumastós) in the treatment of mammographic breast density. A randomized, double-blind study

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    Mammographic breast density is a recognized risk factor for breast cancer. The causes that lead to the proliferation of the glandular breast tissue and, therefore, to an increase of breast density are still unclear. However, a treatment strategy to reduce the mammary density may bring about very relevant clinical outcomes in breast cancer prevention. Myo-inositol is a six-fold alcohol of cyclohexane, has already been proved to modulate different pathways: inflammatory, metabolic, oxidative and endocrine processes, in a wide array of human diseases, including cancer and the genesis of mammary gland and breast diseases, like fibrosis, as well as metabolic and endocrine cues. Similarly, boswellic acid and betaine (three-methyl glycine) both inhibit inflammation and exert protective effects on breast physiology. Based on this scientific background, we hypothesized that a combination including, boswellic acid, betaine and myo-inositol would be able to reduce breast density working on different pathways.OBJECTIVE: Mammographic breast density is a recognized risk factor for breast cancer. The causes that lead to the proliferation of the glandular breast tissue and, therefore, to an increase of breast density are still unclear. However, a treatment strategy to reduce the mammary density may bring about very relevant clinical outcomes in breast cancer prevention. Myo-inositol is a six-fold alcohol of cyclohexane, has already been proved to modulate different pathways: inflammatory, metabolic, oxidative and endocrine processes, in a wide array of human diseases, including cancer and the genesis of mammary gland and breast diseases, like fibrosis, as well as metabolic and endocrine cues. Similarly, boswellic acid and betaine (threemethyl glycine) both inhibit inflammation and exert protective effects on breast physiology. Based on this scientific background, we hypothesized that a combinat ion including, boswellic acid, betaine and myo-inositol would be able to reduce breast density working on different pathways. PATIENTS AND METHODS: In this study, seventy-six premenopausal women were randomly assigned to the placebo and the experimental drug arms (Eumastós®) for six months. RESULTS: After 6 months of treatment, statistically significant difference between the two groups was recorded on the breast density reduction (60% vs. 9%), using mammographic as well as ultrasound examination. CONCLUSIONS: Preliminary data collected here with support the starting assumptions,that the association comprising boswellic acid, betaine and myo-inositol significantly reduces mammary density, providing the first evidence for a new and safe approach for the management of mammographic density treatment

    Simulated microgravity triggers epithelial mesenchymal transition in human keratinocytes

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    The microgravitational environment is known to affect the cellular behaviour inducing modulation of gene expression and enzymatic activities, epigenetic modifications and alterations of the structural organization. Simulated microgravity, obtained in the laboratory setting through the use of a Random Positioning Machine (RPM), represents a well recognized and useful tool for the experimental studies of the cellular adaptations and molecular changes in response to weightlessness. Short exposure of cultured human keratinocytes to the RPM microgravity influences the cellular circadian clock oscillation. Therefore, here we searched for changes on the regenerative ability and response to tissue damage of human epidermal cells through the analysis of the effects of the simulated microgravity on the re-epithelialization phase of the repair and wound healing process. Combining morphological, biochemical and molecular approaches, we found that the simulated microgravity exposure of human keratinocytes promotes a migratory behavior and triggers the epithelial-mesenchymal transition (EMT) through expression of the typical EMT transcription factors and markers, such as Snail1, Snail2 and ZEB2, metalloproteases, mesenchymal adhesion molecules and cytoskeletal components

    Microgravity Induces Transient EMT in Human Keratinocytes by Early Down-Regulation of E-Cadherin and Cell-Adhesion Remodeling

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    Abstract: Changes in cell–matrix and cell-to-cell adhesion patterns are dramatically fostered by the microgravity exposure of living cells. The modification of adhesion properties could promote the emergence of a migrating and invasive phenotype. We previously demonstrated that short exposure to the simulated microgravity of human keratinocytes (HaCaT) promotes an early epithelial– mesenchymal transition (EMT). Herein, we developed this investigation to verify if the cells maintain the acquired invasive phenotype after an extended period of weightlessness exposure. We also evaluated cells’ capability in recovering epithelial characteristics when seeded again into a normal gravitational field after short microgravity exposure. We evaluated the ultra-structural junctional features of HaCaT cells by Transmission Electron Microscopy and the distribution pattern of vinculin and E-cadherin by confocal microscopy, observing a rearrangement in cell–cell and cell–matrix interactions. These results are mirrored by data provided by migration and invasion biological assay. Overall, our studies demonstrate that after extended periods of microgravity, HaCaT cells recover an epithelial phenotype by re-establishing E-cadherin-based junctions and cytoskeleton remodeling, both being instrumental in promoting a mesenchymal–epithelial transition (MET). Those findings suggest that cytoskeletal changes noticed during the first weightlessness period have a transitory character, given that they are later reversed and followed by adaptive modifications through which cells miss the acquired mesenchymal phenotyp

    Inositol induces mesenchymal-epithelial reversion in breast cancer cells through cytoskeleton rearrangement

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    Inositol displays multi-targeted effects on many biochemical pathways involved in epithelial-mesenchymal transition (EMT). As Akt activation is inhibited by inositol, we investigated if such effect could hamper EMT in MDA-MB-231 breast cancer cells. In cancer cells treated with pharmacological doses of inositol E-cadherin was increased, β-catenin was redistributed behind cell membrane, and metalloproteinase-9 was significantly reduced, while motility and invading capacity were severely inhibited. Those changes were associated with a significant down-regulation of PI3K/Akt activity, leading to a decrease in downstream signaling effectors: NF-kB, COX-2, and SNAI1. Inositol-mediated inhibition of PS1 leads to lowered Notch 1 release, thus contributing in decreasing SNAI1 levels. Overall, these data indicated that inositol inhibits the principal molecular pathway supporting EMT. Similar results were obtained in ZR-75, a highly metastatic breast cancer line. These findings are coupled with significant changes on cytoskeleton. Inositol slowed-down vimentin expression in cells placed behind the wound-healing edge and stabilized cortical F-actin. Moreover, lamellipodia and filopodia, two specific membrane extensions enabling cell migration and invasiveness, were no longer detectable after inositol addiction. Additionally, fascin and cofilin, two mandatory required components for F-actin assembling within cell protrusions, were highly reduced. These data suggest that inositol may induce an EMT reversion in breast cancer cells, suppressing motility and invasiveness through cytoskeleton modifications

    The PI3K/AKT pathway is activated by HGF in NT2D1 non-seminoma cells and has a role in the modulation of their malignant behavior

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    Overactivation of the c-MET/HGF system is a feature of many cancers. We previously reported that type II testicular germ cell tumor (TGCT) cells express the c-MET receptor, forming non-seminomatous lesions that are more positive compared with seminomatous ones. Notably, we also demonstrated that NT2D1 non-seminomatous cells (derived from an embryonal carcinoma lesion) increase their proliferation, migration, and invasion in response to HGF. Herein, we report that HGF immunoreactivity is more evident in the microenvironment of embryonal carcinoma biopsies with respect to seminomatous ones, indicating a tumor-dependent modulation of the testicular niche. PI3K/AKT is one of the signaling pathways triggered by HGF through the c-MET activation cascade. Herein, we demonstrated that phospho-AKT increases in NT2D1 cells after HGF stimulation. Moreover, we found that this pathway is involved in HGF-dependent NT2D1 cell proliferation, migration, and invasion, since the co-administration of the PI3K inhibitor LY294002 together with HGF abrogates these responses. Notably, the inhibition of endogenous PI3K affects collective cell migration but does not influence proliferation or chemotactic activity. Surprisingly, LY294002 administered without the co-administration of HGF increases cell invasion at levels comparable to the HGF-administered samples. This paradoxical result highlights the role of the testicular microenvironment in the modulation of cellular responses and stimulates the study of the testicular secretome in cancer lesions
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