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Sample records for lymphatic remodeling induced

  1. Apelin modulates pathological remodeling of lymphatic endothelium after myocardial infarction

    PubMed Central

    Renaud-Gabardos, Edith; Godet, Anne-Claire; Hantelys, Fransky; Pujol, Francoise; Calise, Denis; Viars, Fanny; Valet, Philippe; Masri, Bernard; Prats, Anne-Catherine; Garmy-Susini, Barbara

    2017-01-01

    Lymphatic endothelium serves as a barrier to control fluid balance and immune cell trafficking to maintain tissue homeostasis. Long-term alteration of lymphatic vasculature promotes edema and fibrosis, which is an aggravating factor in the onset of cardiovascular diseases such as myocardial infarction. Apelin is a bioactive peptide that plays a central role in angiogenesis and cardiac contractility. Despite an established role of apelin in lymphangiogenesis, little is known about its function in the cardiac lymphatic endothelium. Here, we show that apelin and its receptor APJ were exclusively expressed on newly formed lymphatic vasculature in a pathological model of myocardial infarction. Using an apelin-knockout mouse model, we identified morphological and functional defects in lymphatic vasculature associated with a proinflammatory status. Surprisingly, apelin deficiency increased the expression of lymphangiogenic growth factors VEGF-C and VEGF-D and exacerbated lymphangiogenesis after myocardial infarction. Conversely, the overexpression of apelin in ischemic heart was sufficient to restore a functional lymphatic vasculature and to reduce matrix remodeling and inflammation. In vitro, the expression of apelin prevented the alteration of cellular junctions in lymphatic endothelial cells induced by hypoxia. In addition, we demonstrated that apelin controls the secretion of the lipid mediator sphingosine-1-phosphate in lymphatic endothelial cells by regulating the level of expression of sphingosine kinase 2 and the transporter SPNS2. Taken together, our results show that apelin plays a key role in lymphatic vessel maturation and stability in pathological settings. Thus, apelin may represent a novel candidate to prevent pathological lymphatic remodeling in diseases. PMID:28614788

  2. Apelin modulates pathological remodeling of lymphatic endothelium after myocardial infarction.

    PubMed

    Tatin, Florence; Renaud-Gabardos, Edith; Godet, Anne-Claire; Hantelys, Fransky; Pujol, Francoise; Morfoisse, Florent; Calise, Denis; Viars, Fanny; Valet, Philippe; Masri, Bernard; Prats, Anne-Catherine; Garmy-Susini, Barbara

    2017-06-15

    Lymphatic endothelium serves as a barrier to control fluid balance and immune cell trafficking to maintain tissue homeostasis. Long-term alteration of lymphatic vasculature promotes edema and fibrosis, which is an aggravating factor in the onset of cardiovascular diseases such as myocardial infarction. Apelin is a bioactive peptide that plays a central role in angiogenesis and cardiac contractility. Despite an established role of apelin in lymphangiogenesis, little is known about its function in the cardiac lymphatic endothelium. Here, we show that apelin and its receptor APJ were exclusively expressed on newly formed lymphatic vasculature in a pathological model of myocardial infarction. Using an apelin-knockout mouse model, we identified morphological and functional defects in lymphatic vasculature associated with a proinflammatory status. Surprisingly, apelin deficiency increased the expression of lymphangiogenic growth factors VEGF-C and VEGF-D and exacerbated lymphangiogenesis after myocardial infarction. Conversely, the overexpression of apelin in ischemic heart was sufficient to restore a functional lymphatic vasculature and to reduce matrix remodeling and inflammation. In vitro, the expression of apelin prevented the alteration of cellular junctions in lymphatic endothelial cells induced by hypoxia. In addition, we demonstrated that apelin controls the secretion of the lipid mediator sphingosine-1-phosphate in lymphatic endothelial cells by regulating the level of expression of sphingosine kinase 2 and the transporter SPNS2. Taken together, our results show that apelin plays a key role in lymphatic vessel maturation and stability in pathological settings. Thus, apelin may represent a novel candidate to prevent pathological lymphatic remodeling in diseases.

  3. Genome-wide functional analysis reveals central signaling regulators of lymphatic endothelial cell migration and remodeling.

    PubMed

    Williams, Steven P; Odell, Adam F; Karnezis, Tara; Farnsworth, Rae H; Gould, Cathryn M; Li, Jason; Paquet-Fifield, Sophie; Harris, Nicole C; Walter, Anne; Gregory, Julia L; Lamont, Sara F; Liu, Ruofei; Takano, Elena A; Nowell, Cameron J; Bower, Neil I; Resnick, Daniel; Smyth, Gordon K; Coultas, Leigh; Hogan, Benjamin M; Fox, Stephen B; Mueller, Scott N; Simpson, Kaylene J; Achen, Marc G; Stacker, Steven A

    2017-10-03

    Lymphatic vessels constitute a specialized vasculature that is involved in development, cancer, obesity, and immune regulation. The migration of lymphatic endothelial cells (LECs) is critical for vessel growth (lymphangiogenesis) and vessel remodeling, processes that modify the lymphatic network in response to developmental or pathological demands. Using the publicly accessible results of our genome-wide siRNA screen, we characterized the migratome of primary human LECs and identified individual genes and signaling pathways that regulate LEC migration. We compared our data set with mRNA differential expression data from endothelial and stromal cells derived from two in vivo models of lymphatic vessel remodeling, viral infection and contact hypersensitivity-induced inflammation, which identified genes selectively involved in regulating LEC migration and remodeling. We also characterized the top candidates in the LEC migratome in primary blood vascular endothelial cells to identify genes with functions common to lymphatic and blood vascular endothelium. On the basis of these analyses, we showed that LGALS1, which encodes the glycan-binding protein Galectin-1, promoted lymphatic vascular growth in vitro and in vivo and contributed to maintenance of the lymphatic endothelial phenotype. Our results provide insight into the signaling networks that control lymphangiogenesis and lymphatic remodeling and potentially identify therapeutic targets and biomarkers in disease specific to lymphatic or blood vessels. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  4. Lymph node biophysical remodeling is associated with melanoma lymphatic drainage.

    PubMed

    Rohner, Nathan Andrew; McClain, Jacob; Tuell, Sara Lydia; Warner, Alex; Smith, Blair; Yun, Youngho; Mohan, Abhinav; Sushnitha, Manuela; Thomas, Susan Napier

    2015-11-01

    Tissue remodeling is a characteristic of many solid tumor malignancies including melanoma. By virtue of tumor lymphatic transport, remodeling pathways active within the local tumor microenvironment have the potential to be operational within lymph nodes (LNs) draining the tumor interstitium. Here, we show that lymphatic drainage from murine B16 melanomas in syngeneic, immune-competent C57Bl/6 mice is associated with LN enlargement as well as nonuniform increases in bulk tissue elasticity and viscoelasticity, as measured by the response of whole LNs to compression. These remodeling responses, which quickly manifest in tumor-draining lymph nodes (TDLNs) after tumor inoculation and before apparent metastasis, were accompanied by changes in matrix composition, including up to 3-fold increases in the abundance of soluble collagen and hyaluronic acid. Intranodal pressures were also significantly increased in TDLNs (+1 cmH2O) relative to both non-tumor-draining LNs (-1 cmH2O) and LNs from naive animals (-1 to 2 cmH2O). These data suggest that the reorganization of matrix structure, composition, and fluid microenvironment within LNs associated with tumor lymphatic drainage parallels remodeling seen in primary malignancies and has the potential to regulate the adhesion, proliferation, and signaling function of LN-resident cells involved in directing melanoma disease progression.

  5. Lymphoid Aggregates Remodel Lymphatic Collecting Vessels that Serve Mesenteric Lymph Nodes in Crohn Disease.

    PubMed

    Randolph, Gwendalyn J; Bala, Shashi; Rahier, Jean-François; Johnson, Michael W; Wang, Peter L; Nalbantoglu, ILKe; Dubuquoy, Laurent; Chau, Amélie; Pariente, Benjamin; Kartheuser, Alex; Zinselmeyer, Bernd H; Colombel, Jean-Frederic

    2016-12-01

    Early pathological descriptions of Crohn disease (CD) argued for a potential defect in lymph transport; however, this concept has not been thoroughly investigated. In mice, poor healing in response to infection-induced tissue damage can cause hyperpermeable lymphatic collecting vessels in mesenteric adipose tissue that impair antigen and immune cell access to mesenteric lymph nodes (LNs), which normally sustain appropriate immunity. To investigate whether analogous changes might occur in human intestinal disease, we established a three-dimensional imaging approach to characterize the lymphatic vasculature in mesenteric tissue from controls or patients with CD. In CD specimens, B-cell-rich aggregates resembling tertiary lymphoid organs (TLOs) impinged on lymphatic collecting vessels that enter and exit LNs. In areas of creeping fat, which characterizes inflammation-affected areas of the bowel in CD, we observed B cells and apparent innate lymphoid cells that had invaded the lymphatic vessel wall, suggesting these cells may be mediators of lymphatic remodeling. Although TLOs have been described in many chronic inflammatory states, their anatomical relationship to preestablished LNs has never been revealed. Our data indicate that, at least in the CD-affected mesentery, TLOs are positioned along collecting lymphatic vessels in a manner expected to affect delivery of lymph to LNs. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  6. A Three-Dimensional Lymphatic Endothelial Cell Tube Formation Assay to Identify Novel Kinases Involved in Lymphatic Vessel Remodeling.

    PubMed

    Gambino, T Jessica; Williams, Steven P; Caesar, Carol; Resnick, Daniel; Nowell, Cameron J; Farnsworth, Rae H; Achen, Marc G; Stacker, Steven A; Karnezis, Tara

    2017-01-01

    The lymphatic system is a series of vessels that transport cells and excess fluid from tissues to the blood vascular system. Normally quiescent, the lymphatics can grow or remodel in response to developmental, immunological, or cells pathological stimuli. Lymphatic vessels comprise lymphatic endothelial cells (LECs) that can respond to external growth factors by undergoing proliferation, migration, adhesion, and tube and lumen formation into new vessel structures, a process known as lymphangiogenesis. To understand the key gene and signaling pathways necessary for lymphangiogenesis and lymphatic vessel remodeling, we have developed a three-dimensional LEC tube formation assay to explore the role of kinase signaling in these processes. The collagen-overlay-based assay was used with primary human adult dermal LECs to investigate a library of 60 tyrosine kinase (TK) and TK-like genes by siRNA knockdown. Nine candidate genes were identified and characterized for their ability to modify key parameters of lymphatic tube formation, including tube length, area, thickness, branching, and number of blind-ended sacs. Four genes-ZAP70, IRAK4, RIPK1, and RIPK2-were identified as high-confidence hits after tertiary deconvolution screens and demonstrate the utility of the assay to define LEC genes critical for the formation of tube structures. This assay facilitates the identification of potential molecular targets for novel drugs designed to modulate the remodeling of lymphatics that is important for the metastatic spread of cancer and other pathologies.

  7. Polydom Is an Extracellular Matrix Protein Involved in Lymphatic Vessel Remodeling.

    PubMed

    Morooka, Nanami; Futaki, Sugiko; Sato-Nishiuchi, Ryoko; Nishino, Masafumi; Totani, Yuta; Shimono, Chisei; Nakano, Itsuko; Nakajima, Hiroyuki; Mochizuki, Naoki; Sekiguchi, Kiyotoshi

    2017-04-14

    Lymphatic vasculature constitutes a second vascular system essential for immune surveillance and tissue fluid homeostasis. Maturation of the hierarchical vascular structure, with a highly branched network of capillaries and ducts, is crucial for its function. Environmental cues mediate the remodeling process, but the mechanism that underlies this process is largely unknown. Polydom (also called Svep1) is an extracellular matrix protein identified as a high-affinity ligand for integrin α9β1. However, its physiological function is unclear. Here, we investigated the role of Polydom in lymphatic development. We generated Polydom-deficient mice. Polydom(-/-) mice showed severe edema and died immediately after birth because of respiratory failure. We found that although a primitive lymphatic plexus was formed, it failed to undergo remodeling in Polydom(-/-) embryos, including sprouting of new capillaries and formation of collecting lymphatic vessels. Impaired lymphatic development was also observed after knockdown/knockout of polydom in zebrafish. Polydom was deposited around lymphatic vessels, but secreted from surrounding mesenchymal cells. Expression of Foxc2 (forkhead box protein c2), a transcription factor involved in lymphatic remodeling, was decreased in Polydom(-/-) mice. Polydom bound to the lymphangiogenic factor Ang-2 (angiopoietin-2), which was found to upregulate Foxc2 expression in cultured lymphatic endothelial cells. Expressions of Tie1/Tie2 receptors for angiopoietins were also decreased in Polydom(-/-) mice. Polydom affects remodeling of lymphatic vessels in both mouse and zebrafish. Polydom deposited around lymphatic vessels seems to ensure Foxc2 upregulation in lymphatic endothelial cells, possibly via the Ang-2 and Tie1/Tie2 receptor system. © 2017 American Heart Association, Inc.

  8. The Lymphatic Endothelial mCLCA1 Antibody Induces Proliferation and Growth of Lymph Node Lymphatic Sinuses

    PubMed Central

    Jordan-Williams, Kimberly L.; Ramanujam, Neela; Farr, Andrew G.

    2016-01-01

    Lymphocyte- and leukocyte-mediated lymph node (LN) lymphatic sinus growth (lymphangiogenesis) is involved in immune responses and in diseases including cancer and arthritis. We previously discovered a 10.1.1 Ab that recognizes the lymphatic endothelial cell (LEC) surface protein mCLCA1, which is an interacting partner for LFA1 and Mac-1 that mediates lymphocyte adhesion to LECs. Here, we show that 10.1.1 Ab treatment specifically induces LEC proliferation, and influences migration and adhesion in vitro. Functional testing by injection of mice with 10.1.1 Ab but not control hamster Abs identified rapid induction of LN LEC proliferation and extensive lymphangiogenesis within 23 h. BrdU pulse-chase analysis demonstrated incorporation of proliferating LYVE-1-positive LEC into the growing medullary lymphatic sinuses. The 10.1.1 Ab-induced LN remodeling involved coordinate increases in LECs and also blood endothelial cells, fibroblastic reticular cells, and double negative stroma, as is observed during the LN response to inflammation. 10.1.1 Ab-induced lymphangiogenesis was restricted to LNs, as mCLCA1-expressing lymphatic vessels of the jejunum and dermis were unaffected by 23 h 10.1.1 Ab treatment. These findings demonstrate that 10.1.1 Ab rapidly and specifically induces proliferation and growth of LN lymphatic sinuses and stroma, suggesting a key role of mCLCA1 in coordinating LN remodeling during immune responses. PMID:27224029

  9. Altered lymphatic function and architecture in salt-induced hypertension assessed by near-infrared fluorescence imaging

    NASA Astrophysics Data System (ADS)

    Kwon, Sunkuk; Agollah, Germaine D.; Chan, Wenyaw; Sevick-Muraca, Eva M.

    2012-08-01

    The lymphatic system plays an important role in maintaining the fluid homeostasis between the blood vascular and interstitial tissue compartment and there is recent evidence that its transport capabilities may regulate blood pressure in salt-induced hypertension. Yet, there is little known how the lymphatic contractile function and architecture responds to dietary salt-intake. Thus, we longitudinally characterized lymphatic contractile function and vessel remodeling noninvasively using dynamic near-infrared fluorescence imaging in animal models of salt-induced hypertension. The lymphatics of mice and rats were imaged following intradermal injection of indocyanine green to the ear tip or the base of the tail before and during two weeks of either a high salt diet (HSD) or normal chow. Our noninvasive imaging data demonstrated dilated lymphatic vessels in the skin of mice and rats on a HSD as compared to their baseline levels. In addition, our dynamic imaging results showed increased lymphatic contraction frequency in HSD-fed mice and rats. Lymphatic contractile function and vessel remodeling occurs in response to salt-induced hypertension suggesting a possible role for the lymphatics in the regulation of vascular blood pressure.

  10. Human Extravillous Trophoblasts Penetrate Decidual Veins and Lymphatics before Remodeling Spiral Arteries during Early Pregnancy

    PubMed Central

    He, Nannan; van Iperen, Liesbeth; de Jong, Danielle; Szuhai, Karoly; Helmerhorst, Frans M.; van der Westerlaken, Lucette A. J.; Chuva de Sousa Lopes, Susana M.

    2017-01-01

    In humans, the defective invasion of the maternal endometrium by fetal extravillous trophoblasts (EVTs) can lead to insufficient perfusion of the placenta, resulting in pregnancy complications that can put both mother and baby at risk. To study the invasion of maternal endometrium between (W)5.5–12 weeks of gestation by EVTs, we combined fluorescence in situ hybridization, immunofluorescence and immunohistochemistry to determine the presence of (male) EVTs in the vasculature of the maternal decidua. We observed that interstitial mononuclear EVTs directly entered decidual veins and lymphatics from W5.5. This invasion of decidual veins and lymphatics occurred long before endovascular EVTs remodelled decidual spiral arteries. This unexpected early entrance of interstitial mononuclear EVTs in the maternal circulation does not seem to contribute to the materno-placental vascular connection directly, but rather to establish (and expand) the materno-fetal interface through an alternative vascular route. PMID:28081266

  11. Monocytes can be induced to express lymphatic phenotypes.

    PubMed

    Changming, W; Xin, L; Hua, T; Shikun, W; Qiong, X; Zhigeng, Z; Xueying, W

    2011-06-01

    Although it has been recently shown that monocytes can transdifferentiate into blood vascular endothelial cells which are involved in angiogenesis, little attention has been paid to their potential to transdifferentiate into lymphatic endothelial cells. Therefore, we examined this question in our study. We first stimulated monocytes with either fibronectin (FN), VEGF-C, TNF-alpha, LPS, or IL-3 for 24h. Then we examined the expression of several markers of lymphatic endothelium and found that the monocytes expressed specific lymphatic endothelial markers, LYVE-1, Podoplanin, and Prox-1, but not common endothelial markers vWF or eNOS. Next, monocytes were incubated in endothelial growth medium with FN and VEGF-C for 6d. These monocytes were also found to express LYVE-1, Podoplanin and Prox-1, but not vWF or eNOS. Our results indicate that monocytes in vitro can be easily induced to present lymphatic phenotypes in an inflammatory environment.

  12. Exercise-induced cardiac remodeling.

    PubMed

    Weiner, Rory B; Baggish, Aaron L

    2012-01-01

    Early investigations in the late 1890s and early 1900s documented cardiac enlargement in athletes with above-normal exercise capacity and no evidence of cardiovascular disease. Such findings have been reported for more than a century and continue to intrigue scientists and clinicians. It is well recognized that repetitive participation in vigorous physical exercise results in significant changes in myocardial structure and function. This process, termed exercise-induced cardiac remodeling (EICR), is characterized by structural cardiac changes including left ventricular hypertrophy with sport-specific geometry (eccentric vs concentric). Associated alterations in both systolic and diastolic functions are emerging as recognized components of EICR. The increasing popularity of recreational exercise and competitive athletics has led to a growing number of individuals exhibiting these findings in routine clinical practice. This review will provide an overview of EICR in athletes.

  13. NOK/STYK1 promotes the genesis and remodeling of blood and lymphatic vessels during tumor progression.

    PubMed

    Liu, Yue; Li, Tianqi; Hu, Dan; Zhang, Shuping

    2016-09-09

    Previous studies have indicated that the overexpression of NOK, also named STYK1, led to tumorigenesis and metastasis. Here, we provide evidence that increased expression of NOK/STYK1 caused marked alterations in the overall and inner structures of tumors and substantially facilitates the genesis and remodeling of the blood and lymphatic vessels during tumor progression. In particular, NOK-expressed HeLa stable cells (HeLa-K) significantly enhanced tumor growth and metastasis in xenografted nude mice. Hematoxylin and eosin (HE) staining demonstrated that the tumor tissues generated by HeLa-K cells were much more ichorous and had more interspaces than those generated by control HeLa cells (HeLa-C). The fluorescent areas stained with cluster of differentiation 31 (CD31), a marker protein for blood vessels, appeared to be in different patterns. The total blood vessels, especially the ring patterns, within the tumors of the HeLa-K group were highly enriched compared with those in the HeLa-C group. NOK-HA was demonstrated to be well colocalized with CD31 in the wall of the tubular structures within tumor tissues. Interestingly, antibody staining of the lymphatic vessel endothelial hyaluronan receptor (LYVE-1) further revealed the increase in ring (oratretic strip-like) lymphatic vessels in either the peritumoral or intratumoral areas in the HeLa-K group compared with the HeLa-C group. Consistently, the analysis of human cancerous tissue also showed that NOK was highly expressed in the walls of tubular structures. Thus, our results reveal a novel tumorigenic function of NOK to mediate the genesis and remodeling of blood and lymphatic vessels during tumor progression. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Synergistic Actions of Blocking Angiopoietin-2 and Tumor Necrosis Factor-α in Suppressing Remodeling of Blood Vessels and Lymphatics in Airway Inflammation

    PubMed Central

    Le, Catherine T.K.; Laidlaw, Grace; Morehouse, Christopher A.; Naiman, Brian; Brohawn, Philip; Mustelin, Tomas; Connor, Jane R.; McDonald, Donald M.

    2016-01-01

    Remodeling of blood vessels and lymphatics are prominent features of sustained inflammation. Angiopoietin-2 (Ang2)/Tie2 receptor signaling and tumor necrosis factor-α (TNF)/TNF receptor signaling are known to contribute to these changes in airway inflammation after Mycoplasma pulmonis infection in mice. We determined whether Ang2 and TNF are both essential for the remodeling on blood vessels and lymphatics, and thereby influence the actions of one another. Their respective contributions to the initial stage of vascular remodeling and sprouting lymphangiogenesis were examined by comparing the effects of function-blocking antibodies to Ang2 or TNF, given individually or together during the first week after infection. As indices of efficacy, vascular enlargement, endothelial leakiness, venular marker expression, pericyte changes, and lymphatic vessel sprouting were assessed. Inhibition of Ang2 or TNF alone reduced the remodeling of blood vessels and lymphatics, but inhibition of both together completely prevented these changes. Genome-wide analysis of changes in gene expression revealed synergistic actions of the antibody combination over a broad range of genes and signaling pathways involved in inflammatory responses. These findings demonstrate that Ang2 and TNF are essential and synergistic drivers of remodeling of blood vessels and lymphatics during the initial stage of inflammation after infection. Inhibition of Ang2 and TNF together results in widespread suppression of the inflammatory response. PMID:26348576

  15. Vegfc acts through ERK to induce sprouting and differentiation of trunk lymphatic progenitors.

    PubMed

    Shin, Masahiro; Male, Ira; Beane, Timothy J; Villefranc, Jacques A; Kok, Fatma O; Zhu, Lihua J; Lawson, Nathan D

    2016-10-15

    Vascular endothelial growth factor C (Vegfc) activates its receptor, Flt4, to induce lymphatic development. However, the signals that act downstream of Flt4 in this context in vivo remain unclear. To understand Flt4 signaling better, we generated zebrafish bearing a deletion in the Flt4 cytoplasmic domain that eliminates tyrosines Y1226 and 1227. Embryos bearing this deletion failed to initiate sprouting or differentiation of trunk lymphatic vessels and did not form a thoracic duct. Deletion of Y1226/7 prevented ERK phosphorylation in lymphatic progenitors, and ERK inhibition blocked trunk lymphatic sprouting and differentiation. Conversely, endothelial autonomous ERK activation rescued lymphatic sprouting and differentiation in flt4 mutants. Interestingly, embryos bearing the Y1226/7 deletion formed a functional facial lymphatic network enabling them to develop normally to adulthood. By contrast, flt4 null larvae displayed hypoplastic facial lymphatics and severe lymphedema. Thus, facial lymphatic vessels appear to be the first functional lymphatic network in the zebrafish, whereas the thoracic duct is initially dispensable for lymphatic function. Moreover, distinct signaling pathways downstream of Flt4 govern lymphatic morphogenesis and differentiation in different anatomical locations. © 2016. Published by The Company of Biologists Ltd.

  16. Temperature-induced cardiac remodelling in fish

    PubMed Central

    Keen, Adam N.; Klaiman, Jordan M.; Shiels, Holly A.

    2017-01-01

    ABSTRACT Thermal acclimation causes the heart of some fish species to undergo significant remodelling. This includes changes in electrical activity, energy utilization and structural properties at the gross and molecular level of organization. The purpose of this Review is to summarize the current state of knowledge of temperature-induced structural remodelling in the fish ventricle across different levels of biological organization, and to examine how such changes result in the modification of the functional properties of the heart. The structural remodelling response is thought to be responsible for changes in cardiac stiffness, the Ca2+ sensitivity of force generation and the rate of force generation by the heart. Such changes to both active and passive properties help to compensate for the loss of cardiac function caused by a decrease in physiological temperature. Hence, temperature-induced cardiac remodelling is common in fish that remain active following seasonal decreases in temperature. This Review is organized around the ventricular phases of the cardiac cycle – specifically diastolic filling, isovolumic pressure generation and ejection – so that the consequences of remodelling can be fully described. We also compare the thermal acclimation-associated modifications of the fish ventricle with those seen in the mammalian ventricle in response to cardiac pathologies and exercise. Finally, we consider how the plasticity of the fish heart may be relevant to survival in a climate change context, where seasonal temperature changes could become more extreme and variable. PMID:27852752

  17. Zika Virus Induced Cellular Remodeling.

    PubMed

    Rossignol, Evan D; Peters, Kristen N; Connor, John H; Bullitt, Esther

    2017-03-20

    Zika virus (ZIKV) has been associated with morbidities such as Guillain-Barré, infant microcephaly, and ocular disease. The spread of this positive-sense, single-stranded RNA virus and its growing public health threat underscore gaps in our understanding of basic ZIKV virology. To advance knowledge of the virus replication cycle within mammalian cells, we use serial section three-dimensional electron tomography to demonstrate the widespread remodeling of intracellular membranes upon infection with ZIKV. We report extensive structural rearrangements of the endoplasmic reticulum and reveal stages of the ZIKV viral replication cycle. Structures associated with RNA genome replication and virus assembly are observed integrated within the endoplasmic reticulum, and we show viruses in transit through the Golgi apparatus for viral maturation, and subsequent cellular egress. This study characterizes in detail the three-dimensional ultrastructural organization of the ZIKV replication cycle stages. Our results show close adherence of the ZIKV replication cycle to the existing flavivirus replication paradigm.

  18. Molecular Aspects of Exercise-induced Cardiac Remodeling.

    PubMed

    Bernardo, Bianca C; McMullen, Julie R

    2016-11-01

    Exercise-induced cardiac remodeling is typically an adaptive response associated with cardiac myocyte hypertrophy and renewal, increased cardiac myocyte contractility, sarcomeric remodeling, cell survival, metabolic and mitochondrial adaptations, electrical remodeling, and angiogenesis. Initiating stimuli/triggers of cardiac remodeling include increased hemodynamic load, increased sympathetic activity, and the release of hormones and growth factors. Prolonged and strenuous exercise may lead to maladaptive exercise-induced cardiac remodeling including cardiac dysfunction and arrhythmia. In addition, this article describes novel therapeutic approaches for the treatment of heart failure that target mechanisms responsible for adaptive exercise-induced cardiac remodeling, which are being developed and tested in preclinical models.

  19. Inflammation induces neuro-lymphatic protein expression in multiple sclerosis brain neurovasculature

    PubMed Central

    2013-01-01

    Background Multiple sclerosis (MS) is associated with ectopic lymphoid follicle formation. Podoplanin+ (lymphatic marker) T helper17 (Th17) cells and B cell aggregates have been implicated in the formation of tertiary lymphoid organs (TLOs) in MS and experimental autoimmune encephalitis (EAE). Since podoplanin expressed by Th17 cells in MS brains is also expressed by lymphatic endothelium, we investigated whether the pathophysiology of MS involves inductions of lymphatic proteins in the inflamed neurovasculature. Methods We assessed the protein levels of lymphatic vessel endothelial hyaluronan receptor and podoplanin, which are specific to the lymphatic system and prospero-homeobox protein-1, angiopoietin-2, vascular endothelial growth factor-D, vascular endothelial growth factor receptor-3, which are expressed by both lymphatic endothelium and neurons. Levels of these proteins were measured in postmortem brains and sera from MS patients, in the myelin proteolipid protein (PLP)-induced EAE and Theiler’s murine encephalomyelitis virus (TMEV) induced demyelinating disease (TMEV-IDD) mouse models and in cell culture models of inflamed neurovasculature. Results and conclusions Intense staining for LYVE-1 was found in neurons of a subset of MS patients using immunohistochemical approaches. The lymphatic protein, podoplanin, was highly expressed in perivascular inflammatory lesions indicating signaling cross-talks between inflamed brain vasculature and lymphatic proteins in MS. The profiles of these proteins in MS patient sera discriminated between relapsing remitting MS from secondary progressive MS and normal patients. The in vivo findings were confirmed in the in vitro cell culture models of neuroinflammation. PMID:24124909

  20. Inflammation induces neuro-lymphatic protein expression in multiple sclerosis brain neurovasculature.

    PubMed

    Chaitanya, Ganta Vijay; Omura, Seiichi; Sato, Fumitaka; Martinez, Nicholas E; Minagar, Alireza; Ramanathan, Murali; Guttman, Bianca Weinstock; Zivadinov, Robert; Tsunoda, Ikuo; Alexander, Jonathan S

    2013-10-14

    Multiple sclerosis (MS) is associated with ectopic lymphoid follicle formation. Podoplanin+ (lymphatic marker) T helper17 (Th17) cells and B cell aggregates have been implicated in the formation of tertiary lymphoid organs (TLOs) in MS and experimental autoimmune encephalitis (EAE). Since podoplanin expressed by Th17 cells in MS brains is also expressed by lymphatic endothelium, we investigated whether the pathophysiology of MS involves inductions of lymphatic proteins in the inflamed neurovasculature. We assessed the protein levels of lymphatic vessel endothelial hyaluronan receptor and podoplanin, which are specific to the lymphatic system and prospero-homeobox protein-1, angiopoietin-2, vascular endothelial growth factor-D, vascular endothelial growth factor receptor-3, which are expressed by both lymphatic endothelium and neurons. Levels of these proteins were measured in postmortem brains and sera from MS patients, in the myelin proteolipid protein (PLP)-induced EAE and Theiler's murine encephalomyelitis virus (TMEV) induced demyelinating disease (TMEV-IDD) mouse models and in cell culture models of inflamed neurovasculature. Intense staining for LYVE-1 was found in neurons of a subset of MS patients using immunohistochemical approaches. The lymphatic protein, podoplanin, was highly expressed in perivascular inflammatory lesions indicating signaling cross-talks between inflamed brain vasculature and lymphatic proteins in MS. The profiles of these proteins in MS patient sera discriminated between relapsing remitting MS from secondary progressive MS and normal patients. The in vivo findings were confirmed in the in vitro cell culture models of neuroinflammation.

  1. Dextran sulfate sodium-induced acute colitis impairs dermal lymphatic function in mice.

    PubMed

    Agollah, Germaine D; Wu, Grace; Peng, Ho-Lan; Kwon, Sunkuk

    2015-12-07

    To investigate whether dermal lymphatic function and architecture are systemically altered in dextran sulfate sodium (DSS)-induced acute colitis. Balb/c mice were administered 4% DSS in lieu of drinking water ad libitum for 7 d and monitored to assess disease activity including body weight, diarrhea severity, and fecal bleeding. Control mice received standard drinking water with no DSS. Changes in mesenteric lymphatics were assessed following oral administration of a fluorescently-labelled fatty acid analogue, while dermal lymphatic function and architecture was longitudinally characterized using dynamic near-infrared fluorescence (NIRF) imaging following intradermal injection of indocyanine green (ICG) at the base of the tail or to the dorsal aspect of the left paw prior to, 4, and 7 d after DSS administration. We also measured dye clearance rate after injection of Alexa680-bovine serum albumin (BSA). NIRF imaging data was analyzed to reveal lymphatic contractile activity after selecting fixed regions of interest (ROIs) of the same size in fluorescent lymphatic vessels on fluorescence images. The averaged fluorescence intensity within the ROI of each fluorescence image was plotted as a function of imaging time and the lymphatic contraction frequency was computed by assessing the number of fluorescent pulses arriving at a ROI. Mice treated with DSS developed acute inflammation with clinical symptoms of loss of body weight, loose feces/watery diarrhea, and fecal blood, all of which were aggravated as disease progressed to 7 d. Histological examination of colons of DSS-treated mice confirmed acute inflammation, characterized by segmental to complete loss of colonic mucosa with an associated chronic inflammatory cell infiltrate that extended into the deeper layers of the wall of the colon, compared to control mice. In situ intravital imaging revealed that mice with acute colitis showed significantly fewer fluorescent mesenteric lymphatic vessels, indicating impaired

  2. Increased nitric oxide production in lymphatic endothelial cells causes impairment of lymphatic drainage in cirrhotic rats.

    PubMed

    Ribera, Jordi; Pauta, Montse; Melgar-Lesmes, Pedro; Tugues, Sònia; Fernández-Varo, Guillermo; Held, Kara F; Soria, Guadalupe; Tudela, Raúl; Planas, Anna M; Fernández-Hernando, Carlos; Arroyo, Vicente; Jiménez, Wladimiro; Morales-Ruiz, Manuel

    2013-01-01

    The lymphatic network plays a major role in maintaining tissue fluid homoeostasis. Therefore several pathological conditions associated with oedema formation result in deficient lymphatic function. However, the role of the lymphatic system in the pathogenesis of ascites and oedema formation in cirrhosis has not been fully clarified. The aim of this study was to investigate whether the inability of the lymphatic system to drain tissue exudate contributes to the oedema observed in cirrhosis. Cirrhosis was induced in rats by CCl(4) inhalation. Lymphatic drainage was evaluated using fluorescent lymphangiography. Expression of endothelial nitric oxide synthase (eNOS) was measured in primary lymphatic endothelial cells (LyECs). Inhibition of eNOS activity in cirrhotic rats with ascites (CH) was carried out by L-N(G)-methyl-L-arginine (L-NMMA) treatment (0.5 mg/kg/day). The (CH) rats had impaired lymphatic drainage in the splanchnic and peripheral regions compared with the control (CT) rats. LyECs isolated from the CH rats showed a significant increase in eNOS and nitric oxide (NO) production. In addition, the lymphatic vessels of the CH rats showed a significant reduction in smooth muscle cell (SMC) coverage compared with the CT rats. CH rats treated with L-NMMA for 7 days showed a significant improvement in lymphatic drainage and a significant reduction in ascites volume, which were associated with increased plasma volume. This beneficial effect of L-NMMA inhibition was also associated with a significant increase in lymphatic SMC coverage. The upregulation of eNOS in the LyECs of CH rats causes long-term lymphatic remodelling, which is characterised by a loss of SMC lymphatic coverage. The amelioration of this lymphatic abnormality by chronic eNOS inhibition results in improved lymphatic drainage and reduced ascites.

  3. Lymphangiogenesis and Lymphatic Metastasis in Breast Cancer

    PubMed Central

    Ran, Sophia; Volk, Lisa; Hall, Kelly; Flister, Michael J.

    2009-01-01

    Lymphatic metastasis is the main prognostic factor for survival of patients with breast cancer and other epithelial malignancies. Mounting clinical and experimental data suggest that migration of tumor cells into the lymph nodes is greatly facilitated by lymphangiogenesis, a process that generates new lymphatic vessels from pre-existing lymphatics with the aid of circulating lymphatic endothelial progenitor cells. The key protein that induces lymphangiogenesis is vascular endothelial growth factor receptor-3 (VEGFR-3), which is activated by vascular endothelial growth factor-C and -D (VEGF-C and VEGF-D). These lymphangiogenic factors are commonly expressed in malignant, tumor-infiltrating and stromal cells, creating a favorable environment for generation of new lymphatic vessels. Clinical evidence demonstrates that increased lymphatic vessel density in and around tumors is associated with lymphatic metastasis and reduced patient survival. Recent evidence shows that breast cancers induce remodeling of the local lymphatic vessels and the regional lymphatic network in the sentinel and distal lymph nodes. These changes include an increase in number and diameter of tumor-draining lymphatic vessels. Consequently, lymph flow away from the tumor is increased, which significantly increases tumor cell metastasis to draining lymph nodes and may contribute to systemic spread. Collectively, recent advances in the biology of tumor-induced lymphangiogenesis suggest that chemical inhibitors of this process may be an attractive target for inhibiting tumor metastasis and cancer-related death. Nevertheless, this is a relatively new field of study and much remains to be established before the concept of tumor-induced lymphangiogenesis is accepted as a viable anti-metastatic target. This review summarizes the current concepts related to breast cancer lymphangiogenesis and lymphatic metastasis while highlighting controversies and unanswered questions. PMID:20036110

  4. Prevention of induced atherosclerosis by diversion of bile or blockade of intestinal lymphatics in dogs.

    PubMed Central

    Wilk, P J; Karipineni, R C; Pertsemlidis, D; Danese, C A

    1976-01-01

    The prevention of induced hypercholesterolemia and atherosclerosis was studied by means of intestinal lymphatic blockade and of bile diversion in the dog. Hypercholesterolemia and atherosclerosis were produced by high cholesterol feeding after induction of hypothyroidism with radio-iodine plus thiouracil. Complete diversion of bile, by shunting all bile into the urinary bladder, effectively prevented hypercholesterolemia and atherosclerosis; in contrast, blockade of the intestinal lymphatics failed to prevent the consequences of the atherogenic regimen, because of the development of collateral lymphatic channels. Images Fig. 3. Fig. 4. Fig. 5. PMID:817679

  5. Efficacy of AdipoDren® in Reducing Interleukin-1-Induced Lymphatic Endothelial Hyperpermeability.

    PubMed

    Ciccone, Valerio; Monti, Martina; Antonini, Giulia; Mattoli, Luisa; Burico, Michela; Marini, Francesca; Maidecchi, Anna; Morbidelli, Lucia

    2016-01-01

    Lymphatic leakage can be seen as a detrimental phenomenon associated with fluid retention and deposition as well as gain of weight. Moreover, lymphatic dysfunction is associated with an inflammatory environment and can be a substrate for other health conditions. A number of treatments can ameliorate lymphatic vasculature: natural substances have been used as treatment options particularly suitable for their consolidated effectiveness and safety profile. Here we report the protective effect of AdipoDren®, an association of a series of plant-derived natural complexes, on lymphatic endothelium permeability promoted by interleukin-1 beta (IL-1β) and the associated molecular mechanisms. AdipoDren® demonstrated a protective effect on dermal lymphatic endothelial cell permeability increased by IL-1β. Reduced permeability was due to the maintenance of tight junctions and cell-cell localisation of occludin and zonula occludens-1 (ZO-1). Moreover, AdipoDren® reduced the expression of the inflammatory key element cyclooxygenase-2 (COX-2), while not altering the levels of endothelial and inducible nitric oxide synthases (eNOS and iNOS). The upregulation of antioxidant enzymatic systems (catalase and superoxide dismutase-1, SOD-1) and the downregulation of pro-oxidant markers (p22 phox subunit of NADPH oxidase) were also evident. In conclusion, AdipoDren® would be useful to ameliorate conditions of altered lymphatic vasculature and to support the physiological functionality of the lymphatic endothelium.

  6. Supermicrosurgical anastomosis of superficial lymphatic vessel to deep lymphatic vessel for a patient with cellulitis-induced chronic localized leg lymphedema.

    PubMed

    Yamamoto, Takumi; Koshima, Isao

    2015-01-01

    Supermicrosurgical lymphaticovenular anastomosis (LVA) has been reported to be useful for the treatment of obstructive lymphedema. However, LVA has a potential risk of anastomosis site thrombosis. It is more physiological to use a lymphatic vessel as a recipient vessel of lymphatic bypass surgery, because there is no chance for blood to contact the anastomosis site. We report a chronic localized lower leg lymphedema case treated with supermicrosurgical superficial-to-deep lymphaticolymphatic anastomosis (LLA). A 66-year-old male with a 60-year history of cellulitis-induced left lower leg lymphedema suffered from very frequent episodes of cellulitis and underwent LLA under local infiltration anesthesia. LLA was performed at the dorsum of the left foot. A dilated superficial lymphatic vessel was found in the fat layer, and a nondilated intact deep lymphatic vessel was found along the dorsalis pedis artery below the deep fascia. The superficial lymphatic vessel was supermicrosurgically anastomosed to the deep lymphatic vessel in a side-to-end fashion. After the surgery, the patient had no episodes of cellulitis, and the left lower leg lymphedematous volume decreased. Superficial-to-deep LLA may be a useful option for the treatment of secondary lymphedema due to obstruction of only the superficial lymphatic system.

  7. Kaposi's sarcoma-associated herpesvirus infection of blood endothelial cells induces lymphatic differentiation.

    PubMed

    Carroll, Patrick A; Brazeau, Elizabeth; Lagunoff, Michael

    2004-10-10

    Kaposi's sarcoma-associated herpesvirus (KSHV) is necessary for KS, a highly vascularized tumor predominated by endothelial-derived spindle cells that express markers of lymphatic endothelium. Following KSHV infection of TIME cells, an immortalized human dermal microvascular endothelial cell (DMVEC) line, expression of many genes specific to lymphatic endothelium, including VEGFR3, podoplanin, LYVE-1, and Prox-1, is significantly increased. Increases in VEGFR3 and podoplanin protein are also demonstrated following latent infection. Examination of cytokine secretion showed that KSHV infection significantly induces hIL-6 while strongly inhibiting secretion of IL-8, a gene product that is decreased by differentiation of blood to lymphatic endothelial cells. These studies support the hypotheses that latent KSHV infection of blood endothelial cells drives their differentiation to lymphatic endothelial cells.

  8. Combining Foxc2 and Connexin37 deletions in mice leads to severe defects in lymphatic vascular growth and remodeling

    PubMed Central

    Kanady, John D.; Munger, Stephanie J.; Witte, Marlys H.; Simon, Alexander M.

    2015-01-01

    Connexins (Cxs), proteins that are vital for intercellular communication in vertebrates, have recently been shown to play a critical role in lymphatic development. However, our knowledge is currently limited regarding the functional relationships of Cxs with other proteins and signaling pathways. Cell culture studies have shown that Cx37 is necessary for coordinated activation of the transcription factor NFATc1, which cooperates with Foxc2 (another transcription factor) during lymphatic endothelial development. These data suggest that Cxs, Foxc2, and NFATc1 are part of a common developmental pathway. Here, we present a detailed characterization of Foxc2 +/−Cx37 −/− mice, demonstrating that lymphatic network architecture and valve formation rely on the concurrent embryonic expression and function of Foxc2 and Cx37. Foxc2 +/−Cx37−/− mice have lymphedema in utero, exhibit craniofacial abnormalities, show severe dilation of intestinal lymphatics, display abnormal lacteal development, lack lymphatic valves, and typically die perinatally (outcomes not seen in Foxc2 +/− or Cx37−/− mice separately). We provide a rigorous, quantitative documentation of lymphatic vascular network changes that highlight the specific structural alterations that occur in Foxc2+/− Cx37−/− mice. These data provide further evidence suggesting that Foxc2 and Cx37 are elements in a common molecular pathway directing lymphangiogenesis. PMID:26079578

  9. Tumors induce coordinate growth of artery, vein, and lymphatic vessel triads

    PubMed Central

    2014-01-01

    Background Tumors drive blood vessel growth to obtain oxygen and nutrients to support tumor expansion, and they also can induce lymphatic vessel growth to facilitate fluid drainage and metastasis. These processes have generally been studied separately, so that it is not known how peritumoral blood and lymphatic vessels grow relative to each other. Methods The murine B16-F10 melanoma and chemically-induced squamous cell carcinoma models were employed to analyze large red-colored vessels growing between flank tumors and draining lymph nodes. Immunostaining and microscopy in combination with dye injection studies were used to characterize these vessels. Results Each peritumoral red-colored vessel was found to consist of a triad of collecting lymphatic vessel, vein, and artery, that were all enlarged. Peritumoral veins and arteries were both functional, as detected by intravenous dye injection. The enlarged lymphatic vessels were functional in most mice by subcutaneous dye injection assay, however tumor growth sometimes blocked lymph drainage to regional lymph nodes. Large red-colored vessels also grew between benign papillomas or invasive squamous cell carcinomas and regional lymph nodes in chemical carcinogen-treated mice. Immunostaining of the red-colored vessels again identified the clustered growth of enlarged collecting lymphatics, veins, and arteries in the vicinity of these spontaneously arising tumors. Conclusions Implanted and spontaneously arising tumors induce coordinate growth of blood and lymphatic vessel triads. Many of these vessel triads are enlarged over several cm distance between the tumor and regional lymph nodes. Lymphatic drainage was sometimes blocked in mice before lymph node metastasis was detected, suggesting that an unknown mechanism alters lymph drainage patterns before tumors reach draining lymph nodes. PMID:24886322

  10. Angiotensin II type 1 and 2 receptors and lymphatic vessels modulate lung remodeling and fibrosis in systemic sclerosis and idiopathic pulmonary fibrosis.

    PubMed

    Parra, Edwin Roger; Ruppert, Aline Domingos Pinto; Capelozzi, Vera Luiza

    2014-01-01

    To validate the importance of the angiotensin II receptor isotypes and the lymphatic vessels in systemic sclerosis and idiopathic pulmonary fibrosis. We examined angiotensin II type 1 and 2 receptors and lymphatic vessels in the pulmonary tissues obtained from open lung biopsies of 30 patients with systemic sclerosis and 28 patients with idiopathic pulmonary fibrosis. Their histologic patterns included cellular and fibrotic non-specific interstitial pneumonia for systemic sclerosis and usual interstitial pneumonia for idiopathic pulmonary fibrosis. We used immunohistochemistry and histomorphometry to evaluate the number of cells in the alveolar septae and the vessels stained by these markers. Survival curves were also used. We found a significantly increased percentage of septal and vessel cells immunostained for the angiotensin type 1 and 2 receptors in the systemic sclerosis and idiopathic pulmonary fibrosis patients compared with the controls. A similar percentage of angiotensin 2 receptor positive vessel cells was observed in fibrotic non-specific interstitial pneumonia and usual interstitial pneumonia. A significantly increased percentage of lymphatic vessels was present in the usual interstitial pneumonia group compared with the non-specific interstitial pneumonia and control groups. A Cox regression analysis showed a high risk of death for the patients with usual interstitial pneumonia and a high percentage of vessel cells immunostained for the angiotensin 2 receptor in the lymphatic vessels. We concluded that angiotensin II receptor expression in the lung parenchyma can potentially control organ remodeling and fibrosis, which suggests that strategies aimed at preventing high angiotensin 2 receptor expression may be used as potential therapeutic target in patients with pulmonary systemic sclerosis and idiopathic pulmonary fibrosis.

  11. Lymph flow regulates collecting lymphatic vessel maturation in vivo

    PubMed Central

    Sweet, Daniel T.; Jiménez, Juan M.; Chang, Jeremy; Hess, Paul R.; Mericko-Ishizuka, Patricia; Fu, Jianxin; Xia, Lijun; Davies, Peter F.; Kahn, Mark L.

    2015-01-01

    Fluid shear forces have established roles in blood vascular development and function, but whether such forces similarly influence the low-flow lymphatic system is unknown. It has been difficult to test the contribution of fluid forces in vivo because mechanical or genetic perturbations that alter flow often have direct effects on vessel growth. Here, we investigated the functional role of flow in lymphatic vessel development using mice deficient for the platelet-specific receptor C-type lectin–like receptor 2 (CLEC2) as blood backfills the lymphatic network and blocks lymph flow in these animals. CLEC2-deficient animals exhibited normal growth of the primary mesenteric lymphatic plexus but failed to form valves in these vessels or remodel them into a structured, hierarchical network. Smooth muscle cell coverage (SMC coverage) of CLEC2-deficient lymphatic vessels was both premature and excessive, a phenotype identical to that observed with loss of the lymphatic endothelial transcription factor FOXC2. In vitro evaluation of lymphatic endothelial cells (LECs) revealed that low, reversing shear stress is sufficient to induce expression of genes required for lymphatic valve development and identified GATA2 as an upstream transcriptional regulator of FOXC2 and the lymphatic valve genetic program. These studies reveal that lymph flow initiates and regulates many of the key steps in collecting lymphatic vessel maturation and development. PMID:26214523

  12. Roles of macrophages in flow-induced outward vascular remodeling

    PubMed Central

    Nuki, Yoshitsugu; Matsumoto, Melissa M; Tsang, Eric; Young, William L; van Rooijen, Nico; Kurihara, Chie; Hashimoto, Tomoki

    2008-01-01

    Sustained hemodynamic stresses, especially sustained high blood flow, result in flow-induced outward vascular remodeling. Mechanisms that link hemodynamic stresses to vascular remodeling are not well understood. Inflammatory cells, known for their release of proteinases, including matrix metalloproteinases (MMPs), are emerging as key mediators for various tissue remodeling. Using a flow-augmented common carotid artery model in rats, we tested whether macrophages play critical roles in adaptive outward vascular remodeling in response to an increase in blood flow. Left common carotid artery ligation caused a sustained increase in blood flow with a gradual increase in luminal diameter in the right common carotid artery. Macrophages infiltrated into the vascular wall that peaked 3 days after flow augmentation. The time course of MMP-9 expression coincided with infiltration of macrophages. Macrophage depletion by liposome-encapsulated dichloromethylene diphosphonate significantly reduced flow-induced outward vascular remodeling, as indicated by the smaller luminal diameter of flow-augmented right common carotid artery in the clodronate-treated group compared with the phosphate-buffered saline-treated group (P < 0.05). These data show critical roles of macrophages in flow-induced outward vascular remodeling. Inflammatory cell infiltration and their subsequent release of cytokines may be key processes for flow-induced outward vascular remodeling. PMID:19002198

  13. Apelin Inhibits Diet-Induced Obesity by Enhancing Lymphatic and Blood Vessel Integrity

    PubMed Central

    Sawane, Mika; Kajiya, Kentaro; Kidoya, Hiroyasu; Takagi, Masaya; Muramatsu, Fumitaka; Takakura, Nobuyuki

    2013-01-01

    Angiogenesis is tightly associated with the outgrowth of adipose tissue, leading to obesity, which is a risk factor for type 2 diabetes and hypertension, mainly because expanding adipose tissue requires an increased nutrient supply from blood vessels. Therefore, induction of vessel abnormality by adipokines has been well-studied, whereas how altered vascular function promotes obesity is relatively unexplored. Also, surviving Prox1 heterozygous mice have shown abnormal lymphatic patterning and adult-onset obesity, indicating that accumulation of adipocytes could be closely linked with lymphatic function. Here, we propose a new antiobesity strategy based on enhancement of lymphatic and blood vessel integrity with apelin. Apelin knockout (KO) mice fed a high-fat diet (HFD) showed an obese phenotype associated with abnormal lymphatic and blood vessel enlargement. Fatty acids present in the HFD induced hyperpermeability of endothelial cells, causing adipocyte differentiation, whereas apelin promoted vascular stabilization. Moreover, treatment of apelin KO mice with a selective cyclooxygenase-2 inhibitor, celecoxib, that were fed an HFD improved vascular function and also attenuated obesity. Finally, apelin transgenic mice showed decreased subcutaneous adipose tissue attributable to inhibition of HFD-induced hyperpermeability of vessels. These results indicate that apelin inhibits HFD-induced obesity by enhancing vessel integrity. Apelin could serve as a therapeutic target for treating obesity and related diseases. PMID:23378608

  14. LYMPHATIC VESSELS IN HEALTH AND DISEASE

    PubMed Central

    Kesler, Cristina T.; Liao, Shan; Munn, Lance L.; Padera, Timothy P.

    2012-01-01

    The lymphatic vasculature plays vital roles in tissue fluid balance, immune defense, metabolism and cancer metastasis. In adults, lymphatic vessel formation and remodeling occurs primarily during inflammation, development of the corpus luteum, wound healing, and tumor growth. Unlike the blood circulation, where unidirectional flow is sustained by the pumping actions of the heart, pumping actions intrinsic to the lymphatic vessels themselves are important drivers of lymphatic flow. This review summarizes critical components that control lymphatic physiology. PMID:23209022

  15. Chronic stress in mice remodels lymph vasculature to promote tumour cell dissemination

    PubMed Central

    Le, Caroline P.; Nowell, Cameron J.; Kim-Fuchs, Corina; Botteri, Edoardo; Hiller, Jonathan G.; Ismail, Hilmy; Pimentel, Matthew A.; Chai, Ming G.; Karnezis, Tara; Rotmensz, Nicole; Renne, Giuseppe; Gandini, Sara; Pouton, Colin W.; Ferrari, Davide; Möller, Andreas; Stacker, Steven A.; Sloan, Erica K.

    2016-01-01

    Chronic stress induces signalling from the sympathetic nervous system (SNS) and drives cancer progression, although the pathways of tumour cell dissemination are unclear. Here we show that chronic stress restructures lymphatic networks within and around tumours to provide pathways for tumour cell escape. We show that VEGFC derived from tumour cells is required for stress to induce lymphatic remodelling and that this depends on COX2 inflammatory signalling from macrophages. Pharmacological inhibition of SNS signalling blocks the effect of chronic stress on lymphatic remodelling in vivo and reduces lymphatic metastasis in preclinical cancer models and in patients with breast cancer. These findings reveal unanticipated communication between stress-induced neural signalling and inflammation, which regulates tumour lymphatic architecture and lymphogenous tumour cell dissemination. These findings suggest that limiting the effects of SNS signalling to prevent tumour cell dissemination through lymphatic routes may provide a strategy to improve cancer outcomes. PMID:26925549

  16. Impaired lymphatic cerebrospinal fluid absorption in a rat model of kaolin-induced communicating hydrocephalus.

    PubMed

    Nagra, G; Li, J; McAllister, J P; Miller, J; Wagshul, M; Johnston, M

    2008-05-01

    It has been assumed that the pathogenesis of hydrocephalus includes a cerebrospinal fluid (CSF) absorption deficit. Because a significant portion of CSF absorption occurs into extracranial lymphatics located in the olfactory turbinates, the purpose of this study was to determine whether CSF transport was compromised at this location in a kaolin-induced communicating (extraventricular) hydrocephalus model in rats. Under 1-3% halothane anesthesia, kaolin (n = 10) or saline (n = 9) was introduced into the basal cisterns of Sprague-Dawley rats, and the development of hydrocephalus was assessed 1 wk later using MRI. After injection of human serum albumin ((125)I-HSA) into a lateral ventricle, the tracer enrichment in the olfactory turbinates 30 min postinjection provided an estimate of CSF transport through the cribriform plate into nasal lymphatics. Lateral ventricular volumes in the kaolin group (0.073 +/- 0.014 ml) were significantly greater than those in the saline-injected animals (0.016 +/- 0.001 ml; P = 0.0014). The CSF tracer enrichment in the olfactory turbinates (expressed as percent injected/g tissue) in the kaolin rats averaged 0.99 +/- 0.39 and was significantly lower than that measured in the saline controls (5.86 +/- 0.32; P < 0.00001). The largest degree of ventriculomegaly was associated with the lowest levels of lymphatic CSF uptake with lateral ventricular expansion occurring only when almost all of the lymphatic CSF transport capacity had been compromised. We conclude that lymphatic CSF absorption is impaired in a kaolin-communicating hydrocephalus model and that the degree of this impediment may contribute to the severity of the induced disease.

  17. Lymphatic vessel development: fluid flow and valve-forming cells.

    PubMed

    Kume, Tsutomu

    2015-08-03

    Hemodynamic forces regulate many aspects of blood vessel disease and development, including susceptibility to atherosclerosis and remodeling of primary blood vessels into a mature vascular network. Vessels of the lymphatic circulatory system are also subjected to fluid flow-associated forces, but the molecular and cellular mechanisms by which these forces regulate the formation and maintenance of lymphatic vessels remain largely uncharacterized. This issue of the JCI includes two articles that begin to address how fluid flow influences lymphatic vessel development and function. Sweet et al. demonstrate that lymph flow is essential for the remodeling of primary lymphatic vessels, for ensuring the proper distribution of smooth muscle cells (SMCs), and for the development and maturation of lymphatic valves. Kazenwadel et al. show that flow-induced lymphatic valve development is initiated by the upregulation of GATA2, which has been linked to lymphedema in patients with Emberger syndrome. Together, these observations and future studies inspired by these results have potential to lead to the development of strategies for the treatment of lymphatic disorders.

  18. FSTL1 PROMOTES ASTHMATIC AIRWAY REMODELING BY INDUCING ONCOSTATIN M

    PubMed Central

    Miller, Marina; Beppu, Andrew; Rosenthal, Peter; Pham, Alexa; Das, Sudipta; Karta, Maya; Song, Dae Jin; Vuong, Christine; Doherty, Taylor; Croft, Michael; Zuraw, Bruce; Zhang, Xu; Gao, Xiang; Aceves, Seema; Chouiali, Fazila; Hamid, Qutayba; Broide, David H.

    2016-01-01

    Chronic asthma is associated with airway remodeling and decline in lung function. Here we show that follistatin like 1 (Fstl1), a mediator not previously associated with asthma is highly expressed by macrophages in the lungs of severe human asthmatics. Chronic allergen challenged Lys-Cretg/Fstl1Δ/Δ mice in whom Fstl1 is inactivated in macrophages/myeloid cells had significantly reduced airway remodeling and reduced levels of oncostatin M (OSM) a cytokine previously not known to be regulated by Fstl1. The importance of the Fstl1 induction of OSM to airway remodeling was demonstrated in murine studies in which administration of Fstl1 induced airway remodeling and increased OSM, while administration of an anti-OSM antibody blocked the effect of Fstl1 on inducing airway remodeling, eosinophilic airway inflammation, and airway hyperresponsiveness all cardinal features of asthma. Overall, these studies demonstrate that the Fstl1/oncostatin M pathway may be a novel pathway to inhibit airway remodeling in severe human asthma. PMID:26355153

  19. CREB Selectively Controls Learning-Induced Structural Remodeling of Neurons

    ERIC Educational Resources Information Center

    Middei, Silvia; Spalloni, Alida; Longone, Patrizia; Pittenger, Christopher; O'Mara, Shane M.; Marie, Helene; Ammassari-Teule, Martine

    2012-01-01

    The modulation of synaptic strength associated with learning is post-synaptically regulated by changes in density and shape of dendritic spines. The transcription factor CREB (cAMP response element binding protein) is required for memory formation and in vitro dendritic spine rearrangements, but its role in learning-induced remodeling of neurons…

  20. CREB Selectively Controls Learning-Induced Structural Remodeling of Neurons

    ERIC Educational Resources Information Center

    Middei, Silvia; Spalloni, Alida; Longone, Patrizia; Pittenger, Christopher; O'Mara, Shane M.; Marie, Helene; Ammassari-Teule, Martine

    2012-01-01

    The modulation of synaptic strength associated with learning is post-synaptically regulated by changes in density and shape of dendritic spines. The transcription factor CREB (cAMP response element binding protein) is required for memory formation and in vitro dendritic spine rearrangements, but its role in learning-induced remodeling of neurons…

  1. Postnatal lymphatic partitioning from the blood vasculature in the small intestine requires fasting-induced adipose factor.

    PubMed

    Bäckhed, Fredrik; Crawford, Peter A; O'Donnell, David; Gordon, Jeffrey I

    2007-01-09

    Lymphatic vessels develop from specialized venous endothelial cells. Using knockout mice, we found that fasting-induced adipose factor (Fiaf) is required for functional partitioning of postnatal intestinal lymphatic and blood vessels. In wild-type animals, levels of intestinal Fiaf expression rise during the first postnatal day and peak at day 2, which coincides with the onset of the lymphatico-venous partitioning abnormality in Fiaf-/- mutants on a mixed 129/SvJ:C57BL/6 genetic background. Fiaf deficiency is not associated with disruption of the blood vasculature or with lymphatic endothelial recruitment of smooth muscle cells. We identified Prox1, a critical regulator of lymphangiogenesis, as a downstream target for Fiaf signaling in the intestinal lymphatic endothelium. This organ-specific lymphovascular abnormality can be rescued by allowing embryonic Fiaf-/- intestinal isografts to develop in Fiaf+/+ recipients.

  2. Cocaine enhances HIV-1 gp120-induced lymphatic endothelial dysfunction in the lung

    PubMed Central

    Zhang, Xuefeng; Jiang, Susan; Yu, Jinlong; Kuzontkoski, Paula M; Groopman, Jerome E

    2015-01-01

    Pulmonary complications are common in both AIDS patients and cocaine users. We addressed the cellular and molecular mechanisms by which HIV and cocaine may partner to induce their deleterious effects. Using primary lung lymphatic endothelial cells (L-LECs), we examined how cocaine and HIV-1 gp120, alone and together, modulate signaling and functional properties of L-LECs. We found that brief cocaine exposure activated paxillin and induced cytoskeletal rearrangement, while sustained exposure increased fibronectin (FN) expression, decreased Robo4 expression, and enhanced the permeability of L-LEC monolayers. Moreover, incubating L-LECs with both cocaine and HIV-1 gp120 exacerbated hyperpermeability, significantly enhanced apoptosis, and further impaired in vitro wound healing as compared with cocaine alone. Our studies also suggested that the sigma-1 receptor (Sigma-1R) and the dopamine-4 receptor (D4R) are involved in cocaine-induced pathology in L-LECs. Seeking clinical correlation, we found that FN levels in sera and lung tissue of HIV+ donors were significantly elevated as compared to HIV− donors. Our in vitro data demonstrate that cocaine and HIV-1 gp120 induce dysfunction and damage of lung lymphatics, and suggest that cocaine use may exacerbate pulmonary edema and fibrosis associated with HIV infection. Continued exploration of the interplay between cocaine and HIV should assist the design of therapeutics to ameliorate HIV-induced pulmonary disorders within the drug using population. PMID:26311830

  3. Dynamical DNA accessibility induced by chromatin remodeling and protein binding

    NASA Astrophysics Data System (ADS)

    Montel, F.; Faivre-Moskalenko, C.; Castelnovo, M.

    2014-11-01

    Chromatin remodeling factors are enzymes being able to alter locally chromatin structure at the nucleosomal level and they actively participate in the regulation of gene expression. Using simple rules for individual nucleosome motion induced by a remodeling factor, we designed simulations of the remodeling of oligomeric chromatin, in order to address quantitatively collective effects in DNA accessibility upon nucleosome mobilization. Our results suggest that accessibility profiles are inhomogeneous thanks to borders effects like protein binding. Remarkably, we show that the accessibility lifetime of DNA sequence is roughly doubled in the vicinity of borders as compared to its value in bulk regions far from the borders. These results are quantitatively interpreted as resulting from the confined diffusion of a large nucleosome depleted region.

  4. Tumor-associated macrophages induce capillary morphogenesis of lymphatic endothelial cells derived from human gastric cancer.

    PubMed

    Tauchi, Yukie; Tanaka, Hiroaki; Kumamoto, Kanako; Tokumoto, Mao; Sakimura, Chie; Sakurai, Katsunobu; Kimura, Kenjiro; Toyokawa, Takahiro; Amano, Ryosuke; Kubo, Naoshi; Muguruma, Kazuya; Yashiro, Masakazu; Maeda, Kiyoshi; Ohira, Masaichi; Hirakawa, Kosei

    2016-08-01

    Tumor lymphangiogenesis is a major prognostic indicator of gastric cancer. Tumor-induced inflammation has been shown to attract tumor-associated macrophages that affect lymphangiogenesis. However, detailed mechanisms of macrophage-induced lymphangiogenesis have not been elucidated. Here, we evaluated the interaction between tumor-associated macrophages and lymphatic endothelial cells (LECs) derived from lymph nodes (LNs) of human gastric cancer. Lymphatic endothelial cells were directly or indirectly cocultured with macrophages from healthy human blood, with or without the supernatant of the gastric cancer cell line, OCUM-12. We analyzed the effect of cancer pretreated macrophages and of macrophages from metastatic LNs of gastric cancer on LECs. We observed morphological changes of LECs in coculture and assessed the gene expression of possible lymphangiogenic molecules of macrophages and LECs after contact coculture, and of cancer pretreated macrophages, by quantitative RT-PCR. Specimens of metastatic LN of gastric cancer were immunofluorescently stained. We found that tubulogenesis of LECs was observed only in the contact coculture model. OCUM-12 cells promoted macrophage-induced tubulogenesis of LECs. Relative gene expression of MMP and adhesion molecules was significantly upregulated in both capillary-forming LECs and cocultured macrophages. Cancer pretreated macrophages upregulated lymphangiogenic factors including inflammatory cytokines, MMPs, adhesion molecules, and vascular endothelial growth factor-C. Blocking of intercellular adhesion molecule-1 and macrophage activation suppressed tubulogenesis of LECs. Immunohistochemistry showed macrophages localized around lymphatic vessels. Our results suggested that interaction between LECs and macrophages may be an important initial step of tumor lymphangiogenesis developing LN metastasis. Understanding of its mechanisms could be useful for future therapeutics of gastric cancer.

  5. Protein Phosphatase 2A in Lipopolysaccharide-Induced Cyclooxygenase-2 Expression in Murine Lymphatic Endothelial Cells

    PubMed Central

    Chuang, Yu-Fan; Chen, Mei-Chieh; Huang, Shiu-Wen; Hsu, Ya-Fen; Ou, George; Tsai, Yu-Jou; Hsu, Ming-Jen

    2015-01-01

    The lymphatic endothelium plays an important role in the maintenance of tissue fluid homeostasis. It also participates in the pathogenesis of several inflammatory diseases. However, little is known about the underlying mechanisms by which lymphatic endothelial cell responds to inflammatory stimuli. In this study, we explored the mechanisms by which lipopolysaccharide (LPS) induces cyclooxygenase (COX)-2 expression in murine lymphatic endothelial cells (SV-LECs). LPS caused increases in cox-2 mRNA and protein levels, as well as in COX-2 promoter luciferase activity in SV-LECs. These actions were associated with protein phosphatase 2A (PP2A), apoptosis signal-regulating kinase 1 (ASK1), JNK1/2 and p38MAPK activation, and NF-κB subunit p65 and C/EBPβ phosphorylation. PP2A-ASK1 signaling blockade reduced LPS-induced JNK1/2, p38MAPK, p65 and C/EBPβ phosphorylation. Transfection with PP2A siRNA reduced LPS’s effects on p65 and C/EBPβ binding to the COX-2 promoter region. Transfected with the NF-κB or C/EBPβ site deletion of COX-2 reporter construct also abrogated LPS’s enhancing effect on COX-2 promoter luciferase activity in SV-LECs. Taken together, the induction of COX-2 in SV-LECs exposed to LPS may involve PP2A-ASK1-JNK and/or p38MAPK-NF-κB and/or C/EBPβ cascade. PMID:26317424

  6. Engineered Split-TET2 Enzyme for Inducible Epigenetic Remodeling

    PubMed Central

    2017-01-01

    The Ten-eleven translocation (TET) family of 5-methylcytosine (5mC) dioxygenases catalyze the conversion of 5mC into 5-hydroxymethylcytosine (5hmC) and further oxidized species to promote active DNA demethylation. Here we engineered a split-TET2 enzyme to enable temporal control of 5mC oxidation and subsequent remodeling of epigenetic states in mammalian cells. We further demonstrate the use of this chemically inducible system to dissect the correlation between DNA hydroxymethylation and chromatin accessibility in the mammalian genome. This chemical-inducible epigenome remodeling tool will find broad use in interrogating cellular systems without altering the genetic code, as well as in probing the epigenotype–phenotype relations in various biological systems. PMID:28294608

  7. Root architecture remodeling induced by phosphate starvation.

    PubMed

    Sato, Aiko; Miura, Kenji

    2011-08-01

    Plants have evolved efficient strategies for utilizing nutrients in the soil in order to survive, grow, and reproduce. Inorganic phosphate (Pi) is a major macroelement source for plant growth; however, the availability and distribution of Pi are varying widely across locations. Thus, plants in many areas experience Pi deficiency. To maintain cellular Pi homeostasis, plants have developed a series of adaptive responses to facilitate external Pi acquisition, limit Pi consumption, and adjust Pi recycling internally under Pi starvation conditions. This review focuses on the molecular regulators that modulate Pi starvation-induced root architectural changes.

  8. Intestinal and peri-tumoral lymphatic endothelial cells are resistant to radiation-induced apoptosis

    SciTech Connect

    Sung, Hoon Ki; Morisada, Tohru; Cho, Chung-Hyun; Oike, Yuichi; Lee, Jayhun; Sung, Eon Ki; Chung, Jae Hoon; Suda, Toshio; Koh, Gou Young . E-mail: gykoh@kaist.ac.kr

    2006-06-30

    Radiation therapy is a widely used cancer treatment, but it is unable to completely block cancer metastasis. The lymphatic vasculature serves as the primary route for metastatic spread, but little is known about how lymphatic endothelial cells respond to radiation. Here, we show that lymphatic endothelial cells in the small intestine and peri-tumor areas are highly resistant to radiation injury, while blood vessel endothelial cells in the small intestine are relatively sensitive. Our results suggest the need for alternative therapeutic modalities that can block lymphatic endothelial cell survival, and thus disrupt the integrity of lymphatic vessels in peri-tumor areas.

  9. Lymphatic response to depilation-induced inflammation in mouse ear assessed with label-free optical lymphangiography.

    PubMed

    Qin, Wan; Baran, Utku; Wang, Ruikang

    2015-10-01

    Optical microangiography (OMAG) is a noninvasive technique capable of imaging 3D microvasculature. OMAG-based optical lymphangiography has been developed for 3D visualization of lymphatic vessels without the need for exogenous contrast agents. In this study, we utilize the optical lymphangiography to investigate dynamic changes in lymphatic response within skin tissue to depilation-induced inflammation by using mouse ear as a simple tissue model. A spectral-domain optical coherence tomography (OCT) system is used in this study to acquire volumetric images of mouse ear. The system operates under the ultrahigh-sensitive OMAG scanning protocol with five repetitions for each B frame. An improved adaptive-threshold-based method is proposed to segment lymphatic vessels from OCT microstructure images. Depilation is achieved by placing hair removal lotion on mouse ear pinna for 5 minutes. Three acquisitions are made before depilation, 3-minute and 30-minute post-depilation, respectively. Right after the application of depilation lotion on the skin, we observe that the blind-ended sacs of initial lymphatics are mainly visible in a specific area of the normal tissue. At 5 minutes, more collecting lymphatic vessels start to form, evidenced by their valve structure that only exists in collecting lymphatic vessels. The lymphangiogenesis is almost completed within 8 minutes in the inflammatory tissue. Our experimental results demonstrate that the OMAG-based optical lymphangiography has great potential to improve the understanding of lymphatic system in response to various physiological conditions, thus would benefit the development of effective therapeutics. © 2015 Wiley Periodicals, Inc.

  10. Lymphatic obstruction

    MedlinePlus

    ... certain directions based on the structure of the lymphatic system. This helps the lymph fluid drain through the ... always appropriate or effective. Alternative Names Lymphedema Images Lymphatic system Yellow nail syndrome References Feldman JL, Jackson KA, ...

  11. Lymphatic Diseases

    MedlinePlus

    The lymphatic system is a network of tissues and organs. It is made up of Lymph - a fluid that contains ... They are part of the system, too. The lymphatic system clears away infection and keeps your body fluids ...

  12. Nuclear translocation of phosphorylated STAT3 regulates VEGF-A-induced lymphatic endothelial cell migration and tube formation

    SciTech Connect

    Okazaki, Hideki; Tokumaru, Sho; Hanakawa, Yasushi; Shiraishi, Ken; Shirakata, Yuji; Dai, Xiuju; Yang, Lijun; Tohyama, Mikiko; Hashimoto, Koji; Sayama, Koji

    2011-09-02

    Highlights: {yields} VEGF-A enhanced lymphatic endothelial cell migration and increased tube formation. {yields} VEGF-A treated lymphatic endothelial cell showed activation of STAT3. {yields} Dominant-negative STAT3 inhibited VEGF-A-induced lymphatic endothelial cell migration and tube formation. -- Abstract: Vascular endothelial growth factor (VEGF) is an endothelial cell-specific growth factor that regulates endothelial functions, and signal transducers and activators of transcription (STATs) are known to be important during VEGF receptor signaling. The aim of this study was to determine whether STAT3 regulates VEGF-induced lymphatic endothelial cell (LEC) migration and tube formation. VEGF-A (33 ng/ml) enhanced LEC migration by 2-fold and increased tube length by 25% compared with the control, as analyzed using a Boyden chamber and Matrigel assay, respectively. Western blot analysis and immunostaining revealed that VEGF-A induced the nuclear translocation of phosphorylated STAT3 in LECs, and this translocation was blocked by the transfection of LECs with an adenovirus vector expressing a dominant-negative mutant of STAT3 (Ax-STAT3F). Transfection with Ax-STAT3F also almost completely inhibited VEGF-A-induced LEC migration and tube formation. These results indicate that STAT3 is essential for VEGF-A-induced LEC migration and tube formation and that STAT3 regulates LEC functions.

  13. Roles of matrix metalloproteinases in flow-induced outward vascular remodeling

    PubMed Central

    Ota, Ryo; Kurihara, Chie; Tsou, Tsung-Ling; Young, William L.; Yeghiazarians, Yerem; Chang, Mayland; Mobashery, Shahriar; Sakamoto, Atsuhiro; Hashimoto, Tomoki

    2009-01-01

    Sustained hemodynamic stresses, especially high blood flow, result in flow-induced outward vascular remodeling. Our previous study showed that macrophage depletion reduced flow-induced outward remodeling of the rat common carotid artery, indicating that macrophages play critical roles in flow-induced outward vascular remodeling. Macrophage is known to release proteinases, including matrix metalloproteinases (MMPs). Degradation and loosening of extracellular matrix by MMPs may facilitate vascular remodeling. Therefore, we assessed the roles of MMPs in flow-induced outward vascular remodeling by using the flow-augmented common carotid artery model in mice. We validated that ligation of the left common carotid artery increased blood flow and luminal diameter of the right common carotid artery without significant change in blood pressure of mice. To assess the roles of MMPs in flow-induced outward vascular remodeling, we used doxycycline (broad-spectrum MMP inhibitor), SB-3CT (selective MMP inhibitor), MMP-9 knockout mice, and MMP-12 knockout mice. Although there was only a trend for doxycycline treatment to reduce flow-induced outward vascular remodeling, SB-3CT treatment significantly reduced flow-induced outward vascular remodeling. In addition, flow-induced outward vascular remodeling was significantly reduced in MMP-9 knockout mice, but not in MMP-12 knockout mice. These data revealed that MMPs, especially MMP-9, play critical roles in flow-induced outward vascular remodeling. PMID:19513084

  14. Focal myocardial infarction induces global remodeling of cardiac sympathetic innervation: neural remodeling in a spatial context

    PubMed Central

    Ajijola, Olujimi A.; Yagishita, Daigo; Patel, Krishan J.; Vaseghi, Marmar; Zhou, Wei; Yamakawa, Kentaro; So, Eileen; Lux, Robert L.; Mahajan, Aman

    2013-01-01

    Myocardial infarction (MI) induces neural and electrical remodeling at scar border zones. The impact of focal MI on global functional neural remodeling is not well understood. Sympathetic stimulation was performed in swine with anteroapical infarcts (MI; n = 9) and control swine (n = 9). A 56-electrode sock was placed over both ventricles to record electrograms at baseline and during left, right, and bilateral stellate ganglion stimulation. Activation recovery intervals (ARIs) were measured from electrograms. Global and regional ARI shortening, dispersion of repolarization, and activation propagation were assessed before and during sympathetic stimulation. At baseline, mean ARI was shorter in MI hearts than control hearts (365 ± 8 vs. 436 ± 9 ms, P < 0.0001), dispersion of repolarization was greater in MI versus control hearts (734 ± 123 vs. 362 ± 32 ms2, P = 0.02), and the infarcted region in MI hearts showed longer ARIs than noninfarcted regions (406 ± 14 vs. 365 ± 8 ms, P = 0.027). In control animals, percent ARI shortening was greater on anterior than posterior walls during right stellate ganglion stimulation (P = 0.0001), whereas left stellate ganglion stimulation showed the reverse (P = 0.0003). In infarcted animals, this pattern was completely lost. In 50% of the animals studied, sympathetic stimulation, compared with baseline, significantly altered the direction of activation propagation emanating from the intramyocardial scar during pacing. In conclusion, focal distal anterior MI alters regional and global pattern of sympathetic innervation, resulting in shorter ARIs in infarcted hearts, greater repolarization dispersion, and altered activation propagation. These conditions may underlie the mechanisms by which arrhythmias are initiated when sympathetic tone is enhanced. PMID:23893167

  15. Hyperglycemia- and hyperinsulinemia-induced insulin resistance causes alterations in cellular bioenergetics and activation of inflammatory signaling in lymphatic muscle.

    PubMed

    Lee, Yang; Fluckey, James D; Chakraborty, Sanjukta; Muthuchamy, Mariappan

    2017-07-01

    Insulin resistance is a well-known risk factor for obesity, metabolic syndrome (MetSyn) and associated cardiovascular diseases, but its mechanisms are undefined in the lymphatics. Mesenteric lymphatic vessels from MetSyn or LPS-injected rats exhibited impaired intrinsic contractile activity and associated inflammatory changes. Hence, we hypothesized that insulin resistance in lymphatic muscle cells (LMCs) affects cell bioenergetics and signaling pathways that consequently alter contractility. LMCs were treated with different concentrations of insulin or glucose or both at various time points to determine insulin resistance. Onset of insulin resistance significantly impaired glucose uptake, mitochondrial function, oxygen consumption rates, glycolysis, lactic acid, and ATP production in LMCs. Hyperglycemia and hyperinsulinemia also impaired the PI3K/Akt while enhancing the ERK/p38MAPK/JNK pathways in LMCs. Increased NF-κB nuclear translocation and macrophage chemoattractant protein-1 and VCAM-1 levels in insulin-resistant LMCs indicated activation of inflammatory mechanisms. In addition, increased phosphorylation of myosin light chain-20, a key regulator of lymphatic muscle contraction, was observed in insulin-resistant LMCs. Therefore, our data elucidate the mechanisms of insulin resistance in LMCs and provide the first evidence that hyperglycemia and hyperinsulinemia promote insulin resistance and impair lymphatic contractile status by reducing glucose uptake, altering cellular metabolic pathways, and activating inflammatory signaling cascades.-Lee, Y., Fluckey, J. D., Chakraborty, S., Muthuchamy, M. Hyperglycemia- and hyperinsulinemia-induced insulin resistance causes alterations in cellular bioenergetics and activation of inflammatory signaling in lymphatic muscle. © FASEB.

  16. Mechanobiology of lymphatic contractions.

    PubMed

    Munn, Lance L

    2015-02-01

    The lymphatic system is responsible for controlling tissue fluid pressure by facilitating flow of lymph (i.e. the plasma and cells that enter the lymphatic system). Because lymph contains cells of the immune system, its transport is not only important for fluid homeostasis, but also immune function. Lymph drainage can occur via passive flow or active pumping, and much research has identified the key biochemical and mechanical factors that affect output. Although many studies and reviews have addressed how tissue properties and fluid mechanics (i.e. pressure gradients) affect lymph transport [1-3] there is less known about lymphatic mechanobiology. As opposed to passive mechanical properties, mechanobiology describes the active coupling of mechanical signals and biochemical pathways. Lymphatic vasomotion is the result of a fascinating system affected by mechanical forces exerted by the flowing lymph, including pressure-induced vessel stretch and flow-induced shear stresses. These forces can trigger or modulate biochemical pathways important for controlling the lymphatic contractions. Here, I review the current understanding of lymphatic vessel function, focusing on vessel mechanobiology, and summarize the prospects for a comprehensive understanding that integrates the mechanical and biomechanical control mechanisms in the lymphatic system.

  17. Periosteal response in translation-induced bone remodelling.

    PubMed Central

    Feik, S A; Ellender, G; Crowe, D M; Ramm-Anderson, S M

    1990-01-01

    Translation of transplanted bones induces strain in the periosteum and subsequent bone remodelling. This study examines the periosteal response on the leading and trailing sides of translated bones using an in vivo model where internal bone strain is virtually eliminated. Caudal vertebrae from 4 days old rats were threaded onto the arms of pre-stressed helical torsion springs and transplanted subcutaneously. In the experimental rats, the appliances were activated seven days later causing the bones to translate. Tissues were examined both optically and by transmission electron microscopy. A connective tissue sheath or capsule forms around the bones and, as the arms of the appliance move apart, traction on the enveloping soft tissues produces compression of the periosteum on the leading side and tension on the trailing side with remodelling occurring in a direction opposite to translation. The control periosteum has an ordered structure with well-delineated osteogenic, mid- and fibrous zones. During translation the periosteum on the leading side is consistently narrower than on the trailing side and shows a gradual reduction in formative activity followed by resorption in select areas. Cells and fibres are aligned predominantly parallel to the bone surface. Accelerated formation characterises the trailing side during the translation phase with increased activity and widening of all three periosteal layers. The fibrous layer merges with the connective tissue sheath which frequently is oriented approximately perpendicular to the bone surface. The direction of remodelling is reversed when translation ceases with corresponding changes visible in the periosteum, the osteoblastic layer being the last to show changes. A normal periosteal structure and remodelling pattern is regained when equilibrium of the bones within the soft tissues is attained. This study shows that the enveloping soft tissues profoundly influence the nature and rate of bone remodelling. The changes are

  18. Elevated CSF outflow resistance associated with impaired lymphatic CSF absorption in a rat model of kaolin-induced communicating hydrocephalus

    PubMed Central

    2010-01-01

    .min, n = 11). There was a significant positive correlation between CSF outflow resistance and ventricular volume. Conclusions The data suggest that the impediment to lymphatic CSF absorption in a kaolin-induced model of communicating hydrocephalus has a significant impact on global CSF absorption. A lymphatic CSF absorption deficit would appear to play some role (either direct or indirect) in the pathogenesis of ventriculomegaly. PMID:20181144

  19. Induced lymphatic sinus hyperplasia in sentinel lymph nodes by VEGF-C as the earliest premetastatic indicator

    PubMed Central

    LIERSCH, RUEDIGER; HIRAKAWA, SATOSHI; BERDEL, WOLFGANG E.; MESTERS, ROLF M.; DETMAR, MICHAEL

    2012-01-01

    Research on tumor-induced lymphangiogenesis has predominantly focused on alterations and abnormal growth of peritumoral and intratumoral lymphatic vessels. However, recent evidence indicates that lymphangiogenesis of sentinel lymph nodes might also contribute to cancer progression. In clinical oncology, the sentinel lymph nodes play an important role in diagnosis, staging and management of disease. The prognostic value that may be placed in the analysis of various parameters in tumor-free lymph nodes is still under debate. We, therefore, chose to investigate genetically fluorescent MDA-MB-435/green fluorescent protein human cancer cells transfected to overexpress VEGF-C in a nude mouse model and investigated metastasis, lymph node lymphangiogenesis, lymph node angiogenesis and size of sentinel lymph nodes. The nature of MDA-MB-435, identified as a breast cancer cell line for several decades, has recently been reidentified as being from melanoma origin. Vascular endothelial growth factor-C overexpression induced early metastasis and significantly increased the lymphatic vessel area in sentinel lymph nodes even before the tumor metastasis. At early time-points, expansion of the lymphatic network was observed even though no difference of blood vessel area and lymph node size was detected. These results suggest that primary tumors -via secretion of VEGF-C- can induce hyperplasia of the sentinel lymph node lymphatic vessel network and thereby promote their further spread. In cases of tumor-free lymph nodes the increased lymphatic network of sentinel lymph nodes is a very early premetastatic sign and may provide a new prognostic indicator and target for aggressive diseases. PMID:23076721

  20. Induced lymphatic sinus hyperplasia in sentinel lymph nodes by VEGF-C as the earliest premetastatic indicator.

    PubMed

    Liersch, Ruediger; Hirakawa, Satoshi; Berdel, Wolfgang E; Mesters, Rolf M; Detmar, Michael

    2012-12-01

    Research on tumor-induced lymphangiogenesis has predominantly focused on alterations and abnormal growth of peritumoral and intratumoral lymphatic vessels. However, recent evidence indicates that lymphangiogenesis of sentinel lymph nodes might also contribute to cancer progression. In clinical oncology, the sentinel lymph nodes play an important role in diagnosis, staging and management of disease. The prognostic value that may be placed in the analysis of various parameters in tumor-free lymph nodes is still under debate. We, therefore, chose to investigate genetically fluorescent MDA-MB-435/green fluorescent protein human cancer cells transfected to overexpress VEGF-C in a nude mouse model and investigated metastasis, lymph node lymphangiogenesis, lymph node angiogenesis and size of sentinel lymph nodes. The nature of MDA-MB-435, identified as a breast cancer cell line for several decades, has recently been reidentified as being from melanoma origin. Vascular endothelial growth factor-C overexpression induced early metastasis and significantly increased the lymphatic vessel area in sentinel lymph nodes even before the tumor metastasis. At early time-points, expansion of the lymphatic network was observed even though no difference of blood vessel area and lymph node size was detected. These results suggest that primary tumors -via secretion of VEGF-C- can induce hyperplasia of the sentinel lymph node lymphatic vessel network and thereby promote their further spread. In cases of tumor-free lymph nodes the increased lymphatic network of sentinel lymph nodes is a very early premetastatic sign and may provide a new prognostic indicator and target for aggressive diseases.

  1. Rutaecarpine attenuates hypoxia-induced right ventricular remodeling in rats.

    PubMed

    Li, Wen-Qun; Li, Xiao-Hui; Du, Jie; Zhang, Wang; Li, Dai; Xiong, Xiao-Ming; Li, Yuan-Jian

    2016-07-01

    Rutaecarpine has been shown to exhibit wide pharmacological effects in the cardiovascular system via stimulation of calcitonin gene-related peptide (CGRP) release. In the present study, the effect of rutaecarpine on hypoxia-induced right ventricular (RV) remodeling and the underlying mechanisms were evaluated. RV remodeling was induced by hypoxia (10 % O2, 3 weeks) in rats. Rats were treated with rutaecarpine (20 or 40 mg/kg) by intragastric administration. Proliferation of cardiac fibroblasts was induced by TGF-β1 (5 ng/mL) and determined by MTS and EdU incorporation method. Cardiac fibroblasts were treated with exogenous CGRP (10 or 100 nM). The concentrations of CGRP and TGF-β1 in plasma were measured by ELISA. The expression of eIF3a, p27, α-SMA, collagen-I/III, ANP, and BNP were measured by real-time PCR or western blot. Hypoxia induced an increase of right ventricle systolic pressure (RVSP), ration of RV/LV+S, and RV/tibial length in rats, while cardiac hypertrophy, apoptosis, and fibrosis were detected. The expression of ANP, BNP, α-SMA, collagen-I, collagen-III, eIF3a, and TGF-β1 was up-regulated, and the expression of p27 was down-regulated in the right ventricle of hypoxia-treated rats. The plasma concentration of CGRP was decreased and TGF-β1 was increased in hypoxia-treated rats. All of these effects induced by hypoxia were attenuated by rutaecarpine in a dose-dependent manner. In cultured cardiac fibroblasts, TGF-β1 significantly promoted the proliferation and up-regulated the expression of α-SMA and collagen-I/III, while the expression of eIF3a was up-regulated and the expression of p27 was down-regulated. The effects of TGF-β1 were attenuated by CGRP. CGRP8-37, a selective CGRP receptor antagonist, abolished the effects of CGRP. Rutaecarpine attenuates hypoxia-induced RV remodeling via stimulation of CGRP release, and the effects of rutaecarpine involve the eIF3a/p27 pathway.

  2. Smooth muscle cell recruitment to lymphatic vessels requires PDGFB and impacts vessel size but not identity.

    PubMed

    Wang, Yixin; Jin, Yi; Mäe, Maarja Andaloussi; Zhang, Yang; Ortsäter, Henrik; Betsholtz, Christer; Mäkinen, Taija; Jakobsson, Lars

    2017-08-29

    Tissue-fluid drains through blind-ended lymphatic capillaries, via smooth muscle cell (SMC)-covered collecting vessels into venous circulation. Both defective SMC recruitment to collecting vessels and ectopic recruitment to lymphatic capillaries are thought to contribute to vessel failure, leading to lymphedema. However, mechanisms controlling lymphatic SMC recruitment and their role in vessel maturation are unknown. Here we demonstrate that platelet-derived growth factor B (PDGFB) regulates lymphatic SMC recruitment in multiple vascular beds. PDGFB is selectively expressed by lymphatic endothelial cells (LECs) of collecting vessels. LEC-specific deletion of Pdgfb prevented SMC recruitment causing dilation and failure of pulsatile contraction of collecting vessels. However, vessel remodelling and identity were unaffected. Unexpectedly, PDGFB overexpression in LECs did not induce SMC recruitment to capillaries. This was explained by the demonstrated requirement of PDGFB extracellular matrix (ECM) retention for lymphatic SMC recruitment, and low presence of PDGFB-binding ECM components around lymphatic capillaries. These results demonstrate a requirement of LEC-autonomous PDGFB expression and retention for SMC recruitment to lymphatic vessels and suggest an ECM-controlled checkpoint preventing SMC investment of capillaries, which is a common feature in lymphedematous skin. © 2017. Published by The Company of Biologists Ltd.

  3. Central Role of Cellular Senescence in TSLP-Induced Airway Remodeling in Asthma

    PubMed Central

    Wu, Jinxiang; Dong, Fangzheng; Wang, Rui-An; Wang, Junfei; Zhao, Jiping; Yang, Mengmeng; Gong, Wenbin; Cui, Rutao; Dong, Liang

    2013-01-01

    Background Airway remodeling is a repair process that occurs after injury resulting in increased airway hyper-responsiveness in asthma. Thymic stromal lymphopoietin (TSLP), a vital cytokine, plays a critical role in orchestrating, perpetuating and amplifying the inflammatory response in asthma. TSLP is also a critical factor in airway remodeling in asthma. Objectives To examine the role of TSLP-induced cellular senescence in airway remodeling of asthma in vitro and in vivo. Methods Cellular senescence and airway remodeling were examined in lung specimens from patients with asthma using immunohischemical analysis. Both small molecule and shRNA approaches that target the senescent signaling pathways were used to explore the role of cellular senescence in TSLP-induced airway remodeling in vitro. Senescence-Associated β-galactosidase (SA-β-Gal) staining, and BrdU assays were used to detect cellular senescence. In addition, the Stat3-targeted inhibitor, WP1066, was evaluated in an asthma mouse model to determine if inhibiting cellular senescence influences airway remodeling in asthma. Results Activation of cellular senescence as evidenced by checkpoint activation and cell cycle arrest was detected in airway epithelia samples from patients with asthma. Furthermore, TSLP-induced cellular senescence was required for airway remodeling in vitro. In addition, a mouse asthma model indicates that inhibiting cellular senescence blocks airway remodeling and relieves airway resistance. Conclusion TSLP stimulation can induce cellular senescence during airway remodeling in asthma. Inhibiting the signaling pathways of cellular senescence overcomes TSLP-induced airway remodeling. PMID:24167583

  4. Microscale mechanisms of agarose-induced disruption of collagen remodeling.

    PubMed

    Ulrich, Theresa A; Lee, Tae Geol; Shon, Hyun Kyong; Moon, Dae Won; Kumar, Sanjay

    2011-08-01

    Cells are strongly influenced by the local structure and mechanics of the extracellular matrix (ECM). We recently showed that adding agarose to soft collagen ECMs can mechanically stiffen these hydrogels by two orders of magnitude while limiting 3D cell motility, which we speculated might derive from agarose-mediated inhibition of collagen fiber deformation and remodeling. Here, we directly address this hypothesis by investigating the effects of agarose on cell-collagen interactions at the microscale. Addition of agarose progressively restricts cell spreading, reduces stress fiber and focal adhesion assembly, and inhibits macroscopic gel compaction. While time-of-flight secondary ion mass spectrometry and scanning electron microscopy fail to reveal agarose-induced alterations in collagen ligand presentation, the latter modality shows that agarose strongly impairs cell-directed assembly of large collagen bundles. Agarose-mediated inhibition of cell spreading and cytoarchitecture can be rescued by β-agarase digestion or by covalently crosslinking the matrix with glutaraldehyde. Based on these results, we argue that cell spreading and motility on collagen requires local matrix stiffening, which can be achieved via cell-mediated fiber remodeling or by chemically crosslinking the fibers. These findings provide new mechanistic insights into the regulatory function of agarose and bear general implications for cell adhesion and motility in fibrous ECMs.

  5. Erythrocyte Stiffness during Morphological Remodeling Induced by Carbon Ion Radiation

    PubMed Central

    Zhang, Baoping; Liu, Bin; Zhang, Hong; Wang, Jizeng

    2014-01-01

    The adverse effect induced by carbon ion radiation (CIR) is still an unavoidable hazard to the treatment object. Thus, evaluation of its adverse effects on the body is a critical problem with respect to radiation therapy. We aimed to investigate the change between the configuration and mechanical properties of erythrocytes induced by radiation and found differences in both the configuration and the mechanical properties with involving in morphological remodeling process. Syrian hamsters were subjected to whole-body irradiation with carbon ion beams (1, 2, 4, and 6 Gy) or X-rays (2, 4, 6, and 12 Gy) for 3, 14 and 28 days. Erythrocytes in peripheral blood and bone marrow were collected for cytomorphological analysis. The mechanical properties of the erythrocytes were determined using atomic force microscopy, and the expression of the cytoskeletal protein spectrin-α1 was analyzed via western blotting. The results showed that dynamic changes were evident in erythrocytes exposed to different doses of carbon ion beams compared with X-rays and the control (0 Gy). The magnitude of impairment of the cell number and cellular morphology manifested the subtle variation according to the irradiation dose. In particular, the differences in the size, shape and mechanical properties of the erythrocytes were well exhibited. Furthermore, immunoblot data showed that the expression of the cytoskeletal protein spectrin-α1 was changed after irradiation, and there was a common pattern among its substantive characteristics in the irradiated group. Based on these findings, the present study concluded that CIR could induce a change in mechanical properties during morphological remodeling of erythrocytes. According to the unique characteristics of the biomechanical categories, we deduce that changes in cytomorphology and mechanical properties can be measured to evaluate the adverse effects generated by tumor radiotherapy. Additionally, for the first time, the current study provides a new

  6. Lymphatic Vascular Response to Acute Inflammation

    PubMed Central

    Lachance, Pier-Anne; Hazen, Amy; Sevick-Muraca, Eva M.

    2013-01-01

    During acute inflammation, functioning lymphatics are believed to reduce edema and to provide a transiting route for immune cells, but the extent at which the dermal lymphatic remodeling impacts lymphatic transport or the factors regulating these changes remains unclear. Herein we quantify the increase in lymphatic endothelial cells (LECs) and examine the expression of pro-angiogenenic and lymphangiogenic factors during acute cutaneous hypersensitivity (CHS). We found that LECs actively proliferate during CHS but that this proliferation does not affect the lymphatic vessel density. Instead, lymphatic remodeling is accompanied by lymphatic vessel leakiness and lower ejection of lymph fluid, which is observed only in the proximal lymphatic vessel draining the inflamed area. LECs and the immune cells release growth factors and cytokines during inflammation, which impact the lymphatic microenvironment and function. We identified that FGF-2, PLGF-2, HGF, EGF, and KC/CXCL17 are differentially expressed within tissues during acute CHS, but both VEGF-C and VEGF-D levels do not significantly change. Our results indicate that VEGF-C and VEGF-D are not the only players and other factors may be responsible for the LECs proliferation and altered lymphatic function in acute CHS. PMID:24086691

  7. TGF-β1-induced EMT promotes targeted migration of breast cancer cells through the lymphatic system by the activation of CCR7/CCL21-mediated chemotaxis.

    PubMed

    Pang, M-F; Georgoudaki, A-M; Lambut, L; Johansson, J; Tabor, V; Hagikura, K; Jin, Y; Jansson, M; Alexander, J S; Nelson, C M; Jakobsson, L; Betsholtz, C; Sund, M; Karlsson, M C I; Fuxe, J

    2016-02-11

    Tumor cells frequently disseminate through the lymphatic system during metastatic spread of breast cancer and many other types of cancer. Yet it is not clear how tumor cells make their way into the lymphatic system and how they choose between lymphatic and blood vessels for migration. Here we report that mammary tumor cells undergoing epithelial-mesenchymal transition (EMT) in response to transforming growth factor-β (TGF-β1) become activated for targeted migration through the lymphatic system, similar to dendritic cells (DCs) during inflammation. EMT cells preferentially migrated toward lymphatic vessels compared with blood vessels, both in vivo and in 3D cultures. A mechanism of this targeted migration was traced to the capacity of TGF-β1 to promote CCR7/CCL21-mediated crosstalk between tumor cells and lymphatic endothelial cells. On one hand, TGF-β1 promoted CCR7 expression in EMT cells through p38 MAP kinase-mediated activation of the JunB transcription factor. Blockade of CCR7, or treatment with a p38 MAP kinase inhibitor, reduced lymphatic dissemination of EMT cells in syngeneic mice. On the other hand, TGF-β1 promoted CCL21 expression in lymphatic endothelial cells. CCL21 acted in a paracrine fashion to mediate chemotactic migration of EMT cells toward lymphatic endothelial cells. The results identify TGF-β1-induced EMT as a mechanism, which activates tumor cells for targeted, DC-like migration through the lymphatic system. Furthermore, it suggests that p38 MAP kinase inhibition may be a useful strategy to inhibit EMT and lymphogenic spread of tumor cells.

  8. Fucoidan Suppresses Hypoxia-Induced Lymphangiogenesis and Lymphatic Metastasis in Mouse Hepatocarcinoma.

    PubMed

    Teng, Hongming; Yang, Yazong; Wei, Hengyun; Liu, Zundong; Liu, Zhichao; Ma, Yanhong; Gao, Zixiang; Hou, Lin; Zou, Xiangyang

    2015-06-03

    Metastasis, the greatest clinical challenge associated with cancer, is closely connected to multiple biological processes, including invasion and adhesion. The hypoxic environment in tumors is an important factor that causes tumor metastasis by activating HIF-1α. Fucoidan, extracted from brown algae, is a sulfated polysaccharide and, as a novel marine biological material, has been used to treat various disorders in China, Korea, Japan and other countries. In the present study, we demonstrated that fucoidan derived from Undaria pinnatifida sporophylls significantly inhibits the hypoxia-induced expression, nuclear translocation and activity of HIF-1α, the synthesis and secretion of VEGF-C and HGF, cell invasion and lymphatic metastasis in a mouse hepatocarcinoma Hca-F cell line. Fucoidan also suppressed lymphangiogenesis in vitro and in vivo. In addition, accompanied by a reduction in the HIF-1α nuclear translocation and activity, fucoidan significantly reduced the levels of p-PI3K, p-Akt, p-mTOR, p-ERK, NF-κB, MMP-2 and MMP-9, but increased TIMP-1 levels. These results indicate strongly that the anti-metastasis and anti-lymphangiogenesis activities of fucoidan are mediated by suppressing HIF-1α/VEGF-C, which attenuates the PI3K/Akt/mTOR signaling pathways.

  9. Mechanosensing in developing lymphatic vessels.

    PubMed

    Planas-Paz, Lara; Lammert, Eckhard

    2014-01-01

    The lymphatic vasculature is responsible for fluid homeostasis, transport of immune cells, inflammatory molecules, and dietary lipids. It is composed of a network of lymphatic capillaries that drain into collecting lymphatic vessels and ultimately bring fluid back to the blood circulation. Lymphatic endothelial cells (LECs) that line lymphatic capillaries present loose overlapping intercellular junctions and anchoring filaments that support fluid drainage. When interstitial fluid accumulates within tissues, the extracellular matrix (ECM) swells and pulls the anchoring filaments. This results in opening of the LEC junctions and permits interstitial fluid uptake. The absorbed fluid is then transported within collecting lymphatic vessels, which exhibit intraluminal valves that prevent lymph backflow and smooth muscle cells that sequentially contract to propel lymph.Mechanotransduction involves translation of mechanical stimuli into biological responses. LECs have been shown to sense and respond to changes in ECM stiffness, fluid pressure-induced cell stretch, and fluid flow-induced shear stress. How these signals influence LEC function and lymphatic vessel growth can be investigated by using different mechanotransduction assays in vitro and to some extent in vivo.In this chapter, we will focus on the mechanical forces that regulate lymphatic vessel expansion during embryonic development and possibly secondary lymphedema. In mouse embryos, it has been recently shown that the amount of interstitial fluid determines the extent of lymphatic vessel expansion via a mechanosensory complex formed by β1 integrin and vascular endothelial growth factor receptor-3 (VEGFR3). This model might as well apply to secondary lymphedema.

  10. Dickkopf-3 attenuates pressure overload-induced cardiac remodelling.

    PubMed

    Zhang, Yan; Liu, Yu; Zhu, Xue-Hai; Zhang, Xiao-Dong; Jiang, Ding-Sheng; Bian, Zhou-Yan; Zhang, Xiao-Fei; Chen, Ke; Wei, Xiang; Gao, Lu; Zhu, Li-Hua; Yang, Qinglin; Fan, Guo-Chang; Lau, Wayne B; Ma, Xinliang; Li, Hongliang

    2014-04-01

    Dickkopf-3 (DKK3), a secreted protein in the Dickkopf family, is expressed in various tissues, including the heart, and has been shown to play an important role in tissue development. However, the biological function of DKK3 in the heart remains largely unexplored. This study aimed to examine the role of DKK3 in pathological cardiac hypertrophy. We performed gain-of-function and loss-of-function studies using DKK3 cardiac-specific transgenic (TG) mice and DKK3 knockout (KO) mice (C57BL/6J background). Cardiac hypertrophy was induced by aortic banding. Cardiac hypertrophy was evaluated by echocardiographic, haemodynamic, pathological, and molecular analyses. Our results demonstrated that the loss of DKK3 exaggerated pressure overload-induced cardiac hypertrophy, fibrosis, and dysfunction, whereas the overexpression of DKK3 protected the heart against pressure overload-induced cardiac remodelling. These beneficial effects were associated with the inhibition of the ASK1-JNK/p38 (apoptosis signal-regulating kinase 1-c-Jun N-terminal kinase/p38) signalling cascade. Parallel in vitro experiments confirmed these in vivo observations. Co-immunoprecipitation experiments suggested that physical interactions occurred between DKK3 and ASK1. Moreover, rescue experiments indicated that, in DKK3 TG mice, the activation of ASK1 using a cardiac-specific conditional ASK1 transgene reduced the functionality of DKK3 in response to pressure overload; furthermore, the inactivation of ASK1 by dominant-negative ASK1 rescued pressure overload-induced cardiac abnormalities in DKK3 KO mice. Taken together, our findings indicate that DKK3 acts as a cardioprotective regulator of pathological cardiac hypertrophy and that this function largely occurs via the regulation of ASK1-JNK/p38 signalling.

  11. Neutrophils rapidly transit inflamed lymphatic vessel endothelium via integrin-dependent proteolysis and lipoxin-induced junctional retraction.

    PubMed

    Rigby, David A; Ferguson, David J P; Johnson, Louise A; Jackson, David G

    2015-12-01

    Neutrophils are the first leukocyte population to be recruited from the circulation following tissue injury or infection, where they play key roles in host defense. However, recent evidence indicates recruited neutrophils can also enter lymph and shape adaptive immune responses downstream in draining lymph nodes. At present, the cellular mechanisms regulating neutrophil entry to lymphatic vessels and migration to lymph nodes are largely unknown. Here, we have investigated these events in an in vivo mouse Mycobacterium bovis bacillus Calmette-Guérin vaccination model, ex vivo mouse dermal explants, and in vitro Transwell system comprising monolayers of primary human dermal lymphatic endothelial cells. We demonstrate that neutrophils are reliant on endothelial activation for adhesion, initially via E-selectin and subsequently, by integrin-mediated binding to ICAM-1 and VCAM-1, combined with CXCL8-dependent chemotaxis. Moreover, we reveal that integrin-mediated neutrophil adhesion plays a pivotal role in subsequent transmigration by focusing the action of matrix metalloproteinases and the 15-lipoxygenase-1-derived chemorepellent 12(S)-hydroxyeicosatetraenoic acid at neutrophil:endothelial contact sites to induce transient endothelial junctional retraction and rapid, selective neutrophil trafficking. These findings reveal an unexpectedly intimate collaboration between neutrophils and the lymphatic vessel endothelium, in which these phagocytic leukocytes act as pathfinders for their own transit during inflammation. © Society for Leukocyte Biology.

  12. Exposure to diesel exhaust particulates induces cardiac dysfunction and remodeling

    PubMed Central

    Bradley, Jessica M.; Cryar, Kipp A.; El Hajj, Milad C.; El Hajj, Elia C.

    2013-01-01

    Chronic exposure to diesel exhaust particulates (DEP) increases the risk of cardiovascular disease in urban residents, predisposing them to the development of several cardiovascular stresses, including myocardial infarctions, arrhythmias, thrombosis, and heart failure. DEP contain a high level of polycyclic aromatic hydrocarbons, which activate the aryl hydrocarbon receptor (AHR). We hypothesize that exposure to DEP elicits ventricular remodeling through the activation of the AHR pathway, leading to ventricular dilation and dysfunction. Male Sprague-Dawley rats were exposed by nose-only nebulization to DEP (SRM 2975, 0.2 mg/ml) or vehicle for 20 min/day × 5 wk. DEP exposure resulted in eccentric left ventricular dilation (8% increased left ventricular internal diameter at diastole and 23% decreased left ventricular posterior wall thickness at diastole vs. vehicle), as shown by echocardiograph assessment. Histological analysis using Picrosirius red staining revealed that DEP reduced cardiac interstitial collagen (23% decrease vs. vehicle). Further assessment of cardiac function using a pressure-volume catheter indicated impaired diastolic function (85% increased end-diastolic pressure and 19% decreased Tau vs. vehicle) and contractility (57 and 48% decreased end-systolic pressure-volume relationship and maximum change in pressure over time vs. end-diastolic volume compared with vehicle, respectively) in the DEP-exposed animals. Exposure to DEP significantly increased cardiac expression of AHR (19% increase vs. vehicle). In addition, DEP significantly decreased the cardiac expression of hypoxia inducible factor-1α, the competitive pathway to the AHR, and vascular endothelial growth factor, a downstream mediator of hypoxia inducible factor-1α (26 and 47% decrease vs. vehicle, respectively). These findings indicate that exposure to DEP induced left ventricular dilation by loss of collagen through an AHR-dependent mechanism. PMID:23887904

  13. PECAM-1 is necessary for flow-induced vascular remodeling

    PubMed Central

    Chen, Zhongming; Tzima, Ellie

    2009-01-01

    OBJECTIVE Vascular remodeling is a physiological process that occurs in response to long-term changes in hemodynamic conditions, but may also contribute to the pathophysiology of intima-media thickening (IMT) and vascular disease. Shear stress detection by the endothelium is thought to be an important determinant of vascular remodeling. Previous work showed that Platelet endothelial cell adhesion molecule-1 (PECAM-1) is a component of a mechanosensory complex that mediates endothelial cell (EC) responses to shear stress. METHODS AND RESULTS We tested the hypothesis that PECAM-1 contributes to vascular remodeling by analyzing the response to partial carotid artery ligation in PECAM-1 knockout mice and wild-type littermates. PECAM-1 deficiency resulted in impaired vascular remodeling and significantly reduced IMT in areas of low flow. Inward remodeling was associated with PECAM-1-dependent NFκB activation, surface adhesion molecule expression and leukocyte infiltration as well as Akt activation and vascular cell proliferation. CONCLUSIONS PECAM-1 plays a crucial role in the activation of the NFκB and Akt pathways and inflammatory cell accumulation during vascular remodeling and IMT. Elucidation of some of the signals that drive vascular remodeling represent pharmacologically tractable targets for the treatment of restenosis after balloon angioplasty or stent placement. PMID:19390054

  14. Pathway-related molecules of VEGFC/D-VEGFR3/NRP2 axis in tumor lymphangiogenesis and lymphatic metastasis.

    PubMed

    Wang, Jingwen; Huang, Yuhong; Zhang, Jun; Wei, Yuanyi; Mahoud, Salma; Bakheet, Ahmed Musa Hago; Wang, Li; Zhou, Shuting; Tang, Jianwu

    2016-10-01

    Precondition for tumor lymphatic metastasis is that tumor cells induce formation of original and newborn lymphatic vessels and invade surrounding lymphatic vessels in tumor stroma, while some pathway-related molecules play an important role in mechanisms associated with proliferation and migration of lymphatic endothelial cells (LECs) and tumor cells. In lymphangiogenesis and lymphatic metastasis, the pathway-related molecules of VEGFC/D-VEGFR3/NRP2 axis, such as Furin-like enzyme, CNTN1, Prox1, LYVE-1, Podoplanin, SOX18, SDF1 and CXCR4, are direct constitutors as a portion of VEGFC/D-VEGFR3/NRP2 axis, and their biological activities rely on this ligand-receptor system. These axis-related signal molecules could gradually produce waterfall-like cascading effects, mediate differentiation and maturation of LECs, remodel original and neonatal lymphatic vessels, as well as ultimately promote tumor cell chemotaxis, migration, invasion and metastasis to lymphoid tracts. This review summarizes the structure and function features of pathway-related molecules of VEGFC/D-VEGFR3/NRP2 axis, the expression changes of these molecules in different anatomic organs or histopathologic types or development stages of various tumors, the characteristics of transduction, implementation, integration of signal networks, the interactive effects on biological behaviors between tumor cells and lymphatic endothelial cells, and their molecular mechanisms and significances in tumor lymphangiogenesis and lymphatic metastasis.

  15. Myocardial remodelling in left ventricular atrophy induced by caloric restriction.

    PubMed

    Gruber, Carina; Nink, Nadine; Nikam, Sandeep; Magdowski, Gerd; Kripp, Gerhard; Voswinckel, Robert; Mühlfeld, Christian

    2012-02-01

    Changes in body weight due to changes in food intake are reflected by corresponding changes in the cardiac phenotype. Despite a growing body of literature on cardiac hypertrophy associated with obesity, little is known on the atrophic remodelling of the heart associated with calorie restriction. We hypothesized that, besides the cardiomyocyte compartment, capillaries and nerve fibres are involved in the atrophic process. C57Bl6 mice were kept on normal diet (control group) or at a calorie-restricted diet for 3 or 7 days (n = 5 each). At the end of the protocol, mice were killed and the hearts were processed for light and electron microscopic stereological analysis of cardiomyocytes, capillaries and nerve fibres. Body, heart and left ventricular weight were significantly reduced in the calorie-restricted animals at 7 days. Most morphological parameters were not significantly different at 3 days compared with the control group, but at 7 days most of them were significantly reduced. Specifically, the total length of capillaries, the volume of cardiomyocytes as well as their subcellular compartments and the interstitium were proportionally reduced during caloric restriction. No differences were observed in the total length or the mean diameter of axons between the cardiomyocytes. Our data indicate that diet-induced left ventricular atrophy leads to a proportional atrophic process of cardiomyocytes and capillaries. The innervation is not involved in the atrophic process. © 2011 The Authors. Journal of Anatomy © 2011 Anatomical Society.

  16. Involvement of H1 and H2 receptors and soluble guanylate cyclase in histamine-induced relaxation of rat mesenteric collecting lymphatics

    PubMed Central

    Kurtz, Kristine H.; Moor, Andrea N.; Souza-Smith, Flavia M.; Breslin, Jerome W.

    2014-01-01

    Objective This study investigated the roles of the H1 and H2 histamine receptors, nitric oxide (NO) synthase, and soluble guanylate (sGC) cyclase in histamine-induced modulation of rat mesenteric collecting lymphatic pumping. Methods Isolated rat mesenteric collecting lymphatics were treated with 1–100 μM histamine. Histamine receptors were blocked with either the H1 antagonist mepyramine or the H2 antagonist cimetidine. The role of NO/sGC signaling was tested using the arginine analog L-NAME, the sGC inhibitor ODQ, and sodium nitroprusside (SNP) as a positive control. Results Histamine applied at 100 μM decreased tone and contraction frequency (CF) of isolated rat mesenteric collecting lymphatics. Pharmacologic blockade of either H1 or H2 histamine receptors significantly inhibited the response to histamine. Pretreatment with ODQ, but not L-NAME, completely inhibited the histamine-induced decrease in tone. ODQ pretreatment also significantly inhibited SNP-induced lymphatic relaxation. Conclusions H1 and H2 histamine receptors are both involved in histamine-induced relaxation of rat mesenteric collecting lymphatics. NO synthesis does not appear to contribute to the histamine-induced response. However, sGC is critical for the histamine-induced decrease in tone and contributes to the drop in CF. PMID:24702851

  17. Mechanisms of Acute Alcohol Intoxication-Induced Modulation of Cyclic Mobilization of [Ca²⁺] in Rat Mesenteric Lymphatic Vessels.

    PubMed

    Souza-Smith, Flavia M; Kerut, Edmund K; Breslin, Jerome W; Molina, Patricia E

    2015-06-01

    We have demonstrated that acute alcohol intoxication (AAI) increases the magnitude of Ca(2+) transients in pumping lymphatic vessels. We tested the contribution of extracellular Ca(2+) via L-type Ca(2+) channels and intracellular Ca(2+) release from the sarcoplasmic reticulum (SR) to the AAI-induced increase in Ca(2+) transients. AAI was produced by intragastric administration of 30% alcohol to conscious, unrestrained rats; isovolumic administration of water served as the control. Mesenteric lymphatic vessels were isolated, cannulated, and loaded with Fura-2 AM to measure changes in intracellular Ca(2+). Measurements were made at intraluminal pressures of 2, 6, and 10 cm H2O. L-type Ca(2+) channels were blocked with nifedipine; IP-3 receptors were inhibited with xestospongin C; and SR Ca(2+) release and Ca(2+) pool (Ca(2+) free APSS) were achieved using caffeine. Nifedipine reduced lymphatic Ca(2+) transient magnitude in both AAI and control groups at all pressures tested, but reduced lymphatic contraction frequency only in the control group. Xestospongin C did not significantly change any of the Ca(2+) parameters in either group; however, fractional shortening increased in the controls at low transmural pressure. RyR (ryanodine receptor) activation with caffeine resulted in a single contraction with a greater Ca(2+) transient in lymphatics from AAI than those from controls. SR Ca(2+) pool was also greater in lymphatics isolated from AAI- than from control animals. These data suggest that 1) L-type Ca(2+) channels contribute to the AAI-induced increase in lymphatic Ca(2+) transient, 2) blockage of IP-3 receptors could increase calcium sensitivity, and 3) AAI increases Ca(2+) storage in the SR in lymphatic vessels.

  18. Downregulation of β-Adrenoceptors in Isoproterenol-Induced Cardiac Remodeling through HuR.

    PubMed

    Yin, Qian; Yang, Chengzhi; Wu, Jimin; Lu, Haiyan; Zheng, Xiaohui; Zhang, Youyi; Lv, Zhizhen; Zheng, Xiaopu; Li, Zijian

    2016-01-01

    β-adrenergic receptors (β-ARs) play an important role in cardiac remodeling, which is the key pathological process in various heart diseases and leads to heart failure. However, the regulation of β-AR expression in remodeling hearts is still unclear. This study aims to clarify the possible mechanisms underlying the regulation of β1- and β2-AR expression in cardiac remodeling. The rat model of cardiac remodeling was established by subcutaneous injection of isoproterenol(ISO) at the dose of 0.25 mg·kg(-1)·d(-1) for 7 days. We found that the expression of β1- and β2-ARs decreased in the remodeling heart. The mechanisms may include the inhibition of DNA transcription and the increase of mRNA degradation. cAMP-response element binding protein(CREB) is a well-known transcription factor of β-AR. However, the expression and activation of CREB was not changed in the remodeling heart. Further, human Antigen-R (HuR), a RNA binding protein, which binds to the 3'-untranslated region of the β-AR mRNA and promotes RNA degradation, was increased in the remodeling model. And in vitro, HuR deficiency reversed the reduction of β-AR mRNA induced by ISO. Therefore, the present findings indicate that HuR, but not CREB, is responsible for the reduction of β-AR expression in ISO induced cardiac remodeling.

  19. Downregulation of β-Adrenoceptors in Isoproterenol-Induced Cardiac Remodeling through HuR

    PubMed Central

    Yin, Qian; Yang, Chengzhi; Wu, Jimin; Lu, Haiyan; Zheng, Xiaohui; Zhang, Youyi; Lv, Zhizhen; Zheng, Xiaopu; Li, Zijian

    2016-01-01

    β-adrenergic receptors (β-ARs) play an important role in cardiac remodeling, which is the key pathological process in various heart diseases and leads to heart failure. However, the regulation of β-AR expression in remodeling hearts is still unclear. This study aims to clarify the possible mechanisms underlying the regulation of β1- and β2-AR expression in cardiac remodeling. The rat model of cardiac remodeling was established by subcutaneous injection of isoproterenol(ISO) at the dose of 0.25 mg·kg−1·d−1 for 7days. We found that the expression of β1- and β2-ARs decreased in the remodeling heart. The mechanisms may include the inhibition of DNA transcription and the increase of mRNA degradation. cAMP-response element binding protein(CREB) is a well-known transcription factor of β-AR. However, the expression and activation of CREB was not changed in the remodeling heart. Further, human Antigen-R (HuR), a RNA binding protein, which binds to the 3'-untranslated region of the β-AR mRNA and promotes RNA degradation, was increased in the remodeling model. And in vitro, HuR deficiency reversed the reduction of β-AR mRNA induced by ISO. Therefore, the present findings indicate that HuR, but not CREB, is responsible for the reduction of β-AR expression in ISO induced cardiac remodeling. PMID:27035432

  20. Use of a PEG-conjugated bright near-infrared dye for functional imaging of rerouting of tumor lymphatic drainage after sentinel lymph node metastasis

    PubMed Central

    Proulx, Steven T.; Luciani, Paola; Christiansen, Ailsa; Karaman, Sinem; Blum, Katrin S.; Rinderknecht, Matthias; Leroux, Jean-Christophe; Detmar, Michael

    2013-01-01

    Tumor lymphangiogenesis promotes metastatic cancer spread to lymph nodes and beyond. However, the potential remodeling and functionality of tumor-draining lymphatic vessels has remained unclear. Thus, we aimed to develop non-invasive imaging methods for repeated quantitative imaging of lymphatic drainage and of contractile collecting lymphatic vessel function in mice, with colloidal near-infrared (NIR) tracers and a custom fluorescence stereomicroscope specially adapted for NIR sensitive imaging. Using these tools, we quantitatively determined pulse rates and valvular function of collecting lymphatic vessels with high resolution. Unexpectedly, we found that tumor-draining lymphatic vessels in a melanoma footpad model initially were dilated but remained functional, despite lower pulse rates. In two independent tumor models, impaired lymphatic function was detected once metastases were present in draining lymph nodes. Importantly, we found that lymphatic dysfunction, induced by metastatic tumor spread to sentinel lymph nodes, can lead to a rerouting of lymphatic flow away from the metastatic lymph node, via collateral lymphatic vessels, to alternate lymph nodes. These findings might have important clinical implications for the procedure of sentinel lymph node mapping that represents the standard of care for determining prognosis and treatment of melanoma and breast cancer patients. PMID:23566803

  1. Disruption of TGF-β signaling in smooth muscle cell prevents flow-induced vascular remodeling

    SciTech Connect

    Gao, Fu; Chambon, Pierre; Tellides, George; Kong, Wei; Zhang, Xiaoming; Li, Wei

    2014-11-07

    Highlights: • TGF-β signaling in SMC contributes to the flow-induced vascular remodeling. • Disruption of TGF-β signaling in SMC can prevent this process. • Targeting SM-specific Tgfbr2 could be a novel therapeutic strategy for vascular remodeling. - Abstract: Transforming growth factor-β (TGF-β) signaling has been prominently implicated in the pathogenesis of vascular remodeling, especially the initiation and progression of flow-induced vascular remodeling. Smooth muscle cells (SMCs) are the principal resident cells in arterial wall and are critical for arterial remodeling. However, the role of TGF-β signaling in SMC for flow-induced vascular remodeling remains unknown. Therefore, the goal of our study was to determine the effect of TGF-β pathway in SMC for vascular remodeling, by using a genetical smooth muscle-specific (SM-specific) TGF-β type II receptor (Tgfbr2) deletion mice model. Mice deficient in the expression of Tgfbr2 (MyhCre.Tgfbr2{sup f/f}) and their corresponding wild-type background mice (MyhCre.Tgfbr2{sup WT/WT}) underwent partial ligation of left common carotid artery for 1, 2, or 4 weeks. Then the carotid arteries were harvested and indicated that the disruption of Tgfbr2 in SMC provided prominent inhibition of vascular remodeling. And the thickening of carotid media, proliferation of SMC, infiltration of macrophage, and expression of matrix metalloproteinase (MMP) were all significantly attenuated in Tgfbr2 disruption mice. Our study demonstrated, for the first time, that the TGF-β signaling in SMC plays an essential role in flow-induced vascular remodeling and disruption can prevent this process.

  2. Lymphatic filariasis.

    PubMed

    2008-02-01

    (1) Lymphatic filariasis is a set of parasitic diseases that are endemic in tropical and subtropical regions and can be disabling in the long term. (2) The standard antiparasitic drug for adults is oral diethylcarbamazine. Ivermectin is an alternative, especially for patients with intercurrent onchocercosis or loasis.

  3. Morphogenesis of the lymphatic vasculature: A focus on new progenitors and cellular mechanisms important for constructing lymphatic vessels.

    PubMed

    Kazenwadel, Jan; Harvey, Natasha L

    2016-03-01

    Lymphatic vessels serve crucial roles in the regulation of tissue fluid homeostasis, dietary lipid absorption and immune cell trafficking. Defects in lymphatic vessel morphogenesis and function have been associated with lymphedema, obesity, hypertension and tumour metastasis. Morphogenetic events important for construction of the lymphatic vasculature during development include the specification and emergence of lymphatic endothelial progenitor cells, their differentiation and assembly into interconnected vessels and vascular remodeling, ultimately giving rise to a functional vascular network. Despite the embryonic origins of lymphatic endothelial progenitor cells being long debated, work performed over the last decade had overwhelmingly supported at least a great majority of progenitor cells arising from the venous vasculature. Here, we review the most recent advances in the field of lymphatic vessel morphogenesis, with a focus on studies that have identified novel sources of embryonic lymphatic endothelial progenitor cells, together with the cellular mechanisms by which lymphatic vessels are initially assembled. © 2015 Wiley Periodicals, Inc.

  4. Ectodomain Shedding of Lymphatic Vessel Endothelial Hyaluronan Receptor 1 (LYVE-1) Is Induced by Vascular Endothelial Growth Factor A (VEGF-A)*

    PubMed Central

    Nishida-Fukuda, Hisayo; Araki, Ryoichi; Shudou, Masachika; Okazaki, Hidenori; Tomono, Yasuko; Nakayama, Hironao; Fukuda, Shinji; Sakaue, Tomohisa; Shirakata, Yuji; Sayama, Koji; Hashimoto, Koji; Detmar, Michael; Higashiyama, Shigeki; Hirakawa, Satoshi

    2016-01-01

    Lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1), a type I transmembrane glycoprotein, is known as one of the most specific lymphatic vessel markers in the skin. In this study, we found that the ectodomain of LYVE-1 undergoes proteolytic cleavage, and this process produces soluble LYVE-1. We further identified the cleavage site for ectodomain shedding and generated an uncleavable mutant of LYVE-1. In lymphatic endothelial cells, ectodomain shedding of LYVE-1 was induced by vascular endothelial growth factor (VEGF)-A, an important factor for angiogenesis and lymphangiogenesis under pathological conditions. VEGF-A-induced LYVE-1 ectodomain shedding was mediated via the extracellular signal-regulated kinase (ERK) and a disintegrin and metalloproteinase (ADAM) 17. Wild-type LYVE-1, but not uncleavable LYVE-1, promoted migration of lymphatic endothelial cells in response to VEGF-A. Immunostaining analyses in human psoriasis skin lesions and VEGF-A transgenic mouse skin suggested that the ectodomain shedding of LYVE-1 occurred in lymphatic vessels undergoing chronic inflammation. These results indicate that the ectodomain shedding of LYVE-1 might be involved in promoting pathological lymphangiogenesis. PMID:26966180

  5. Slug Is Increased in Vascular Remodeling and Induces a Smooth Muscle Cell Proliferative Phenotype

    PubMed Central

    Coll-Bonfill, Núria; Peinado, Victor I.; Pisano, María V.; Párrizas, Marcelina; Blanco, Isabel; Evers, Maurits; Engelmann, Julia C.; García-Lucio, Jessica; Tura-Ceide, Olga; Meister, Gunter

    2016-01-01

    Objective Previous studies have confirmed Slug as a key player in regulating phenotypic changes in several cell models, however, its role in smooth muscle cells (SMC) has never been assessed. The purpose of this study was to evaluate the expression of Slug during the phenotypic switch of SMC in vitro and throughout the development of vascular remodeling. Methods and Results Slug expression was decreased during both cell-to-cell contact and TGFβ1 induced SMC differentiation. Tumor necrosis factor-α (TNFα), a known inductor of a proliferative/dedifferentiated SMC phenotype, induces the expression of Slug in SMC. Slug knockdown blocked TNFα-induced SMC phenotypic change and significantly reduced both SMC proliferation and migration, while its overexpression blocked the TGFβ1-induced SMC differentiation and induced proliferation and migration. Genome-wide transcriptomic analysis showed that in SMC, Slug knockdown induced changes mainly in genes related to proliferation and migration, indicating that Slug controls these processes in SMC. Notably, Slug expression was significantly up-regulated in lungs of mice using a model of pulmonary hypertension-related vascular remodeling. Highly remodeled human pulmonary arteries also showed an increase of Slug expression compared to less remodeled arteries. Conclusions Slug emerges as a key transcription factor driving SMC towards a proliferative phenotype. The increased Slug expression observed in vivo in highly remodeled arteries of mice and human suggests a role of Slug in the pathogenesis of pulmonary vascular diseases. PMID:27441378

  6. Preclinical Lymphatic Imaging

    PubMed Central

    Zhang, Fan; Niu, Gang; Lu, Guangming; Chen, Xiaoyuan

    2011-01-01

    Non-invasive in vivo imaging of lymphatic vessels and lymphatic nodes is expected to fulfill the purpose of analyzing lymphatic vessels and their function, understanding molecular mechanisms of lymphangiogenesis and lymphatic spread of tumors, and utilizing lymphatic molecular markers as a prognostic or diagnostic indicator. In this review, we provide a comprehensive summary of in vivo imaging modalities for detecting lymphatic vessels, lymphatic drainage, lymphatic nodes, which include conventional lymphatic imaging techniques such as dyes and radionuclide scintigraphy as well as novel techniques for lymphatic imaging such as optical imaging, computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, positron emission tomography (PET) using lymphatic biomarkers, photoacoustic imaging and combinations of multiple modalities. The field of lymphatic imaging is ever evolving, and technological advances, combined with the development of new contrast agents, continue to improve the research of lymphatic vascular system in health and disease states as well as to improve the accuracy of diagnosis in the relevant diseases. PMID:20862613

  7. CT-1-CP-induced ventricular electrical remodeling in mice.

    PubMed

    Chen, Shu-fen; Wei, Tao-zhi; Rao, Li-ya; Xu, Ming-guang; Dong, Zhan-ling

    2015-02-01

    The chronic effects of carboxyl-terminal polypeptide of Cardiotrophin-1 (CT-1-CP) on ventricular electrical remodeling were investigated. CT-1-CP, which contains 16 amino acids in sequence of the C-terminal of Cardiotrophin-1, was selected and synthesized, and then administered to Kunming mice (aged 5 weeks) by intraperitoneal injection (500 ng·g⁻¹·day⁻¹) (4 groups, n=10 and female: male=1:1 in each group) for 1, 2, 3 and 4 weeks, respectively. The control group (n=10, female: male=1:1) was injected by physiological saline for 4 weeks. The epicardial monophasic action potential (MAP) was recorded by using a contact-type MAP electrode placed vertically on the left ventricular (LV) epicardium surface, and the electrocardiogram (ECG) signal in lead II was monitored synchronously. ECG intervals (RR, PR, QRS and QT) and the amplitude of MAP (Am), the maximum upstroke velocity (Vmax), as well as action potential durations (APDs) at different repolarization levels (APD30, APD50, APD70, and APD90) of MAP were determined and analyzed in detail. There were no significant differences in RR and P intervals between CT-1-CP-treated groups and control group, but the PR segment and the QRS complex were greater in the former than in the latter (F=2.681 and 5.462 respectively, P<0.05). Though QT interval and the corrected QT interval (QTc) were shorter in CT-1-CP-treated groups than in control group, the QT dispersion (QTd) of them was greater in the latter than in the former (F=3.090, P<0.05) and increased with the time. The ECG monitoring synchronously with the MAP showed that the compression of MAP electrode on the left ventricular epicardium induced performance similar to myocardium ischemia. As compared with those before chest-opening, the PR segment and QT intervals remained basically unchanged in control group, but prolonged significantly in all CT-1-CP-treated groups and the prolongation of QT intervals increased gradually along with the time of exposure to CT-1-CP

  8. Emphysema and mechanical stress-induced lung remodeling.

    PubMed

    Suki, Béla; Sato, Susumu; Parameswaran, Harikrishnan; Szabari, Margit V; Takahashi, Ayuko; Bartolák-Suki, Erzsébet

    2013-11-01

    Transpulmonary pressure and the mechanical stresses of breathing modulate many essential cell functions in the lung via mechanotransduction. We review how mechanical factors could influence the pathogenesis of emphysema. Although the progression of emphysema has been linked to mechanical rupture, little is known about how these stresses alter lung remodeling. We present possible new directions and an integrated multiscale view that may prove useful in finding solutions for this disease.

  9. A Computational Model for Simulating Spaceflight Induced Bone Remodeling

    NASA Technical Reports Server (NTRS)

    Pennline, James A.; Mulugeta, Lealem

    2014-01-01

    An overview of an initial development of a model of bone loss due to skeletal unloading in weight bearing sites is presented. The skeletal site chosen for the initial application of the model is the femoral neck region because hip fractures can be debilitating to the overall performance health of astronauts. The paper begins with the motivation for developing such a model of the time course of change in bone in order to understand the mechanism of bone demineralization experienced by astronauts in microgravity, to quantify the health risk, and to establish countermeasures. Following this, a general description of a mathematical formulation of the process of bone remodeling is discussed. Equations governing the rate of change of mineralized bone volume fraction and active osteoclast and osteoblast are illustrated. Some of the physiology of bone remodeling, the theory of how imbalance in remodeling can cause bone loss, and how the model attempts to capture this is discussed. The results of a preliminary validation analysis that was carried out are presented. The analysis compares a set of simulation results against bone loss data from control subjects who participated in two different bed rest studies. Finally, the paper concludes with outlining the current limitations and caveats of the model, and planned future work to enhance the state of the model.

  10. Hypoxia Increases Breast Cancer Cell-Induced Lymphatic Endothelial Cell Migration12

    PubMed Central

    Mikhaylova, Maria; Mori, Noriko; Wildes, Flonné B; Walczak, Piotr; Gimi, Barjor; Bhujwalla, Zaver M

    2008-01-01

    Because tumors are characterized by hypoxic environments, we used a novel in vitro noninvasive magnetic resonance imaging assay to examine the influence of invasive MDA-MB-231 breast cancer cells on the invasion and migration of human dermal lymphatic microvascular endothelial cells (HMVEC-dLy) under normoxic and hypoxic conditions. Nonmalignant immortalized MCF-12A human mammary epithelial cells instead of cancer cells or chambers with HMVEC-dLy alone were used as controls for comparison. HMVEC-dLy cells were labeled with a T2 contrast agent (Feridex), and their invasion and migration through extracellular matrix under normoxic and hypoxic conditions were monitored using magnetic resonance imaging. A significant increase in the invasion and migration of HMVEC-dLy cells was detected in the presence of cancer cells, which further increased significantly under hypoxic conditions. HMVEC-dLy cells formed interconnecting strands extending toward the cancer cells under normoxic but not under hypoxic conditions. Following reoxygenation, these interconnecting strands, extending from HMVEC-dLy cells toward the cancer cells, were observed. These data demonstrate the importance of hypoxia in lymphatic endothelial cell invasion and migration through extracellular matrix in the presence of cancer cells. PMID:18392137

  11. Extracellular Matrix Remodeling During the Progression of Volume Overload-Induced Heart Failure

    PubMed Central

    Hutchinson, Kirk R.; Stewart, James A.; Lucchesi, Pamela A.

    2009-01-01

    Volume overload-induced heart failure results in progressive left ventricular remodeling characterized by chamber dilation, eccentric cardiac myocyte hypertrophy and changes in extracellular matrix (ECM) remodeling changes. The ECM matrix scaffold is an important determinant of the structural integrity of the myocardium and actively participates in force transmission across the LV wall. In response to this hemodynamic overload, the ECM undergoes a distinct pattern of remodeling that differs from pressure overload. Once thought to be a static entity, the ECM is now regarded to be a highly adaptive structure that is dynamically regulated by mechanical stress, neurohormonal activation, inflammation and oxidative stress, that result in alterations in collagen and other matrix components and a net change in matrix metalloproteinase (MMP) expression and activation. These changes dictate overall ECM turnover during volume overload hear failure progression. This review will discuss the cellular and molecular mechanisms that dictate the temporal patterns of ECM remodeling during heart disease progression. PMID:19524591

  12. Trabecular bone remodelling simulation considering osteocytic response to fluid-induced shear stress.

    PubMed

    Adachi, Taiji; Kameo, Yoshitaka; Hojo, Masaki

    2010-06-13

    In bone functional adaptation by remodelling, osteocytes in the lacuno-canalicular system are believed to play important roles in the mechanosensory system. Under dynamic loading, bone matrix deformation generates an interstitial fluid flow in the lacuno-canalicular system; this flow induces shear stress on the osteocytic process membrane that is known to stimulate the osteocytes. In this sense, the osteocytes behave as mechanosensors and deliver mechanical information to neighbouring cells through the intercellular communication network. In this study, bone remodelling is assumed to be regulated by the mechanical signals collected by the osteocytes. From the viewpoint of multi-scale biomechanics, we propose a mathematical model of trabecular bone remodelling that takes into account the osteocytic mechanosensory network system. Based on this model, a computational simulation of trabecular bone remodelling was conducted for a single trabecula under cyclic uniaxial loading, demonstrating functional adaptation to the applied mechanical loading as a load-bearing construct.

  13. Grape seed proanthocyanidin extract alleviates ouabain-induced vascular remodeling through regulation of endothelial function.

    PubMed

    Liu, Xiangju; Qiu, Jie; Zhao, Shaohua; You, Beian; Ji, Xiang; Wang, Yan; Cui, Xiaopei; Wang, Qian; Gao, Haiqing

    2012-11-01

    Recent studies indicate that chronic ouabain treatment leads to hypertension and hypertensive vascular remodeling. Grape seed proanthocyanidin extract (GSPE) has been reported to be effective in treating arteriosclerosis, while little is known about its effect on systolic blood pressure and vascular remodeling. In this study, the effects of GSPE on systolic blood pressure and vascular remodeling were analyzed by treating ouabain-induced hypertensive rats with GSPE (250 mg/kg·d). The expression of nitric oxide (NO) and endothelin-1 (ET-1) in thoracic aorta was examined by ELISA; the mRNA and protein levels of TGF-β1 were detected using real-time PCR and western blotting, respectively. The results showed that the systolic blood pressure was significantly decreased following treatment with GSPE, with blocked vascular remodeling. The ET-1 content was reduced while NO production was increased in the GSPE group, which showed improved vascular endothelial function. Moreover, GSPE also reduced TGF-β1 expression in the thoracic aorta, which is a determinant in vascular remodeling. In conclusion, GSPE antagonized ouabain-induced hypertension and vascular remodeling and is recommended as a potential anti-hypertensive agent for patients with hypertensive vascular diseases.

  14. Autophagy plays a role in FSTL1-induced epithelial mesenchymal transition and airway remodeling in asthma.

    PubMed

    Liu, Tian; Liu, Yahui; Miller, Marina; Cao, Liuzhao; Zhao, Jiping; Wu, Jinxiang; Wang, Junfei; Liu, Lin; Li, Shuo; Zou, Minfang; Xu, Jiawei; Broide, David H; Dong, Liang

    2017-07-01

    Asthma is a chronic disease related to airway hyperresponsiveness and airway remodeling. Airway remodeling is the important reason of refractory asthma and is associated with differentiation of airway epithelia into myofibroblasts via epithelial-mesenchymal transition (EMT) to increase the process of subepithelial fibrosis. There is growing evidence that autophagy modulates remodeling. However, the underlying molecular mechanisms of these effects are still unclear. In this study, we hypothesized that Follistatin-like 1 (FSTL1) promotes EMT and airway remodeling by intensifying autophagy. With the use of transmission electron microscopy (TEM), double-membrane autophagosomes were detected in the airways of patients and mice. More autophagosomes were in patients with asthma and OVA-challenged mice compared with healthy controls. The expression of FSTL1 and beclin-1 was upregulated in the airways of patients with asthma and OVA-challenged mice, accompanied by airway EMT and remodeling. In OVA-challenged Fstl1(+/-) mice, the degree of airway remodeling and autophagy was decreased compared with control mice. The effects of FSTL1 on autophagy and EMT were also tested in 16HBE cells in vitro. Additionally, inhibition of autophagy by using LY-294002 and siRNA-ATG5 reduced the FSTL1-induced EMT in 16HBE cells, as measured by E-cadherin, N-cadherin, and vimentin expression. In line herewith, administration of LY-294002 reduced the expression of autophagy, EMT, and airway remodeling markers in FSTL1-challenged WT mice. Taken together, our study suggests that FSTL1 may induce EMT and airway remodeling by activating autophagy. These findings may provide novel avenues for therapeutic research targeting the autophagy and FSTL1 pathway, which may be beneficial to patients with refractory asthma. Copyright © 2017 the American Physiological Society.

  15. Lymphatic Education & Research Network

    MedlinePlus

    Lymphatic Education & Research Network Donate Now Become a Supporting Member X Living with LYMPHEDEMA AND Lymphatic Disease FAQs About ... 261 Madison Avenue, New York, NY 10016 | Lymphatic Education & Research Network is a 501(c)(3) under ...

  16. Lymphatic Anomalies Registry

    ClinicalTrials.gov

    2016-07-26

    Lymphatic Malformation; Generalized Lymphatic Anomaly (GLA); Central Conducting Lymphatic Anomaly; CLOVES Syndrome; Gorham-Stout Disease ("Disappearing Bone Disease"); Blue Rubber Bleb Nevus Syndrome; Kaposiform Lymphangiomatosis; Kaposiform Hemangioendothelioma/Tufted Angioma; Klippel-Trenaunay Syndrome; Lymphangiomatosis

  17. Mechanical force-induced midpalatal suture remodeling in mice

    PubMed Central

    Hou, Bo; Fukai, Naomi; Olsen, Bjorn R.

    2007-01-01

    Mechanical stress is an important epigenetic factor for regulating skeletal remodeling, and application of force can lead to remodeling of both bone and cartilage. Chondrocytes, osteoblasts and osteoclasts all participate and interact with each other in this remodeling process. To study cellular responses to mechanical stimuli in a system that can be genetically manipulated, we used mouse midpalatal suture expansion in vivo. 6-weeks-old male C57BL/6 mice were subjected to palatal suture expansion by opening loops with an initial force of 0.56N for periods of 1, 3, 7, 14 or 28 days. Periosteal cells in expanding sutures showed increased proliferation, with Ki67 positive cells representing 1.8±0.1% to 4.5±0.4% of total suture cells in control groups and 12.0±2.6% to 19.9±1.2% in experimental/expansion groups (p<0.05). Starting at day 1, cells expressing alkaline phosphatase and type I collagen were seen. New cartilage and bone formation was observed at the oral edges of the palatal bones at day 7; at the nasal edges only bone formation without cartilage appeared to occur. An increase in osteoclast numbers suggested increased bone remodeling, ranging from 60 to 160% throughout the experimental period. Decreased Saffranin O staining after day 3 suggested decreased proteoglycan content in the secondary cartilage. MicroCT showed a significant increase in maxillary width at days 14 and 28 (from 2334±4μm to 2485±3μm at day 14 and from 2383±5μm to 2574±7μm at day 28, p<0.001). The suture width was increased at days 14 and 28, except in the oral third region at day 28 (from 48±5μm to 36±4μm, p<0.05). Bone volume/total volume was significantly reduced at days 14 and 28 (50.2±0.7% vs. 68.0±3.7% and 56.5±1.0%vs. 60.9±1.3%, respectively, p<0.05), indicative of increased bone marrow space. These findings demonstrate that expansion forces across the midpalatal suture promote bone resorption through activation of osteoclasts and bone and cartilage formation via

  18. Changes in pulmonary arterial wall mechanical properties and lumenal architecture with induced vascular remodeling

    NASA Astrophysics Data System (ADS)

    Molthen, Robert C.; Heinrich, Amy E.; Haworth, Steven T.; Dawson, Christopher A.

    2004-04-01

    To explore and quantify pulmonary arterial remodeling we used various methods including micro-CT, high-resolution 3-dimensional x-ray imaging, to examine the structure and function of intact pulmonary vessels in isolated rat lungs. The rat is commonly used as an animal model for studies of pulmonary hypertension (PH) and the accompanying vascular remodeling, where vascular remodeling has been defined primarily by changes in the vessel wall composition in response to hypertension inducing stimuli such as chronic hypoxic exposure (CHE) or monocrotaline (MCT) injection. Little information has been provided as to how such changes affect the vessel wall mechanical properties or the lumenal architecture of the pulmonary arterial system that actually account for the hemodynamic consequences of the remodeling. In addition, although the link between primary forms of pulmonary hypertension and inherited genetics is well established, the role that genetic coding plays in hemodynamics and vascular remodeling is not. Therefore, we are utilizing Fawn-Hooded (FH), Sprague-Dawley (SD) and Brown Norway (BN)rat strains along with unique imaging methods to parameterize both vessel distensibility and lumenal morphometry using a principal pulmonary arterial pathway analysis based on self-consistency. We have found for the hypoxia model, in addition to decreased body weight, increased hematocrit, increased right ventricular hypertrophy, the distensibility of the pulmonary arteries is shown to decrease significantly in the presence of remodeling.

  19. MD2 Blockage Protects Obesity-Induced Vascular Remodeling via Activating AMPK/Nrf2.

    PubMed

    Wang, Lintao; Han, Jibo; Shan, Peiren; You, Shengban; Chen, Xuemei; Jin, Yiyi; Wang, Jingying; Huang, Weijian; Wang, Yi; Liang, Guang

    2017-09-01

    Obesity and increased free fatty acid (FFA) levels are tightly linked with vascular oxidative stress and remodeling. Myeloid differentiation 2 (MD2), an important protein in innate immunity, is requisite for endotoxin lipopolysaccharide responsiveness. This study shows that palmitic acid (PA) also bonds to MD2, initiating cardiac inflammatory injury. However, it is not clear whether MD2 plays a role in noninflammatory systems such as obesity- and FFA-related oxidative stress involved in vascular remodeling and injury. The aim of this study is to examine whether MD2 participates in reactive oxygen species increase and vascular remodeling. Male MD2(-/-) mice and wild-type littermates with a C57BL/6 background were fed a high-fat diet (HFD) to establish obesity-induced vascular remodeling. Rat aortic endothelial cells (RAECs) and vascular smooth muscle cells (VSMCs) were treated with PA to induce oxidative stress and injury. In vivo, MD2 deficiency significantly reduced HFD-induced vascular oxidative stress, fibrosis, and remodeling, accompanied with AMP-activated kinase (AMPK) activation and nuclear factor erythroid (Nrf2) upregulation. In VSMCs and RAECs, inhibition of MD2 by neutralizing monoclonal antibody to MD2 or small interfering RNA knockdown significantly activated the AMPK/Nrf2-signaling pathway and reduced PA-induced oxidative stress and cell injury. It was demonstrated that the deletion or inhibition of MD2 protects against HFD/FFA-induced vascular oxidative stress and remodeling by activating the AMPK/Nrf2-signaling pathway. © 2017 The Obesity Society.

  20. Molecular Mechanism for the (-)-Epigallocatechin Gallate-Induced Toxic to Nontoxic Remodeling of Aβ Oligomers.

    PubMed

    Ahmed, Rashik; VanSchouwen, Bryan; Jafari, Naeimeh; Ni, Xiaodan; Ortega, Joaquin; Melacini, Giuseppe

    2017-10-04

    (-)-Epigallocatechin gallate (EGCG) effectively reduces the cytotoxicity of the Alzheimer's disease β-amyloid peptide (Aβ) by remodeling seeding-competent Aβ oligomers into off-pathway seeding-incompetent Aβ assemblies. However, the mechanism of EGCG-induced remodeling is not fully understood. Here we combine (15)N and (1)H dark-state exchange saturation transfer (DEST), relaxation, and chemical shift projection NMR analyses with fluorescence, dynamic light scattering, and electron microscopy to elucidate how EGCG remodels Aβ oligomers. We show that the remodeling adheres to a Hill-Scatchard model whereby the Aβ(1-40) self-association occurs cooperatively and generates Aβ(1-40) oligomers with multiple independent binding sites for EGCG with a Kd ∼10-fold lower than that for the Aβ(1-40) monomers. Upon binding to EGCG, the Aβ(1-40) oligomers become less solvent exposed, and the β-regions, which are involved in direct monomer-protofibril contacts in the absence of EGCG, undergo a direct-to-tethered contact shift. This switch toward less engaged monomer-protofibril contacts explains the seeding incompetency observed upon EGCG remodeling and suggests that EGCG interferes with secondary nucleation events known to generate toxic Aβ assemblies. Unexpectedly, the N-terminal residues experience an opposite EGCG-induced shift from tethered to direct contacts, explaining why EGCG remodeling occurs without release of Aβ(1-40) monomers. We also show that upon binding Aβ(1-40) oligomers the relative positions of the EGCG B and D rings change with respect to that of ring A. These distinct structural changes occurring in both Aβ(1-40) oligomers and EGCG during remodeling offer a foundation for understanding the molecular mechanism of EGCG as a neurotoxicity inhibitor. Furthermore, the results reported here illustrate the effectiveness of DEST-based NMR approaches in investigating the mechanism of low-molecular-weight amyloid inhibitors.

  1. Combinatorial Control of Light Induced Chromatin Remodeling and Gene Activation in Neurospora

    PubMed Central

    Sancar, Cigdem; Ha, Nati; Yilmaz, Rüstem; Tesorero, Rafael; Fisher, Tamas; Brunner, Michael; Sancar, Gencer

    2015-01-01

    Light is an important environmental cue that affects physiology and development of Neurospora crassa. The light-sensing transcription factor (TF) WCC, which consists of the GATA-family TFs WC1 and WC2, is required for light-dependent transcription. SUB1, another GATA-family TF, is not a photoreceptor but has also been implicated in light-inducible gene expression. To assess regulation and organization of the network of light-inducible genes, we analyzed the roles of WCC and SUB1 in light-induced transcription and nucleosome remodeling. We show that SUB1 co-regulates a fraction of light-inducible genes together with the WCC. WCC induces nucleosome eviction at its binding sites. Chromatin remodeling is facilitated by SUB1 but SUB1 cannot activate light-inducible genes in the absence of WCC. We identified FF7, a TF with a putative O-acetyl transferase domain, as an interaction partner of SUB1 and show their cooperation in regulation of a fraction of light-inducible and a much larger number of non light-inducible genes. Our data suggest that WCC acts as a general switch for light-induced chromatin remodeling and gene expression. SUB1 and FF7 synergistically determine the extent of light-induction of target genes in common with WCC but have in addition a role in transcription regulation beyond light-induced gene expression. PMID:25822411

  2. Gasoline exhaust emissions induce vascular remodeling pathways involved in atherosclerosis.

    PubMed

    Lund, Amie K; Knuckles, Travis L; Obot Akata, Chrys; Shohet, Ralph; McDonald, Jacob D; Gigliotti, Andrew; Seagrave, Jean Clare; Campen, Matthew J

    2007-02-01

    Epidemiological evidence indicates that environmental air pollutants are positively associated with the development of chronic vascular disease; however, the mechanisms involved have not been fully elucidated. In the present study we examined molecular pathways associated with chronic vascular disease in atherosclerosis-prone apolipoprotein E-deficient (ApoE(-/-)) mice, including markers of vascular remodeling and oxidative stress, in response to exposure to the ubiquitous environmental pollutant, gasoline engine emissions. ApoE(-/-) mice, on a high-fat diet, were exposed by inhalation to either filtered air; 8, 40, or 60 mug/m(3) particulate matter whole exhaust; or filtered exhaust with gases matching the 60-mug/m(3) concentration, for 7 weeks. Aortas and plasma were collected and assayed for changes in histochemical markers, real-time reverse transcriptase-polymerase chain reaction, and indicators of oxidative damage. Inhalational exposure to gasoline engine emissions resulted in increased aortic mRNA expression of matrix metalloproteinase-3 (MMP-3), MMP-7, and MMP-9, tissue inhibitor of metalloproteinases-2, endothelin-1 and heme oxygenase-1 in ApoE(-/-) mice; increased aortic MMP-9 protein levels were confirmed through immunohistochemistry. Elevated reactive oxygen species were also observed in arteries from exposed animals, despite absence of plasma markers. Similar findings were also observed in the aortas of ApoE(-/-) mice exposed to particle-filtered atmosphere, implicating the gaseous components of the whole exhaust in mediating the expression of markers associated with the vasculopathy. These findings demonstrate that exposure to gasoline engine emissions results in the transcriptional upregulation of factors associated with vascular remodeling, as well as increased markers of vascular oxidative stress, which may contribute to the progression of atherosclerosis and reduced stability of vulnerable plaques.

  3. Radiotherapy-induced right ventricular remodelling: The missing piece of the puzzle.

    PubMed

    Tadic, Marijana; Cuspidi, Cesare; Hering, Dagmara; Venneri, Lucia; Grozdic-Milojevic, Isidora

    2017-02-01

    The number of studies demonstrating that right ventricular structure, function and mechanics are valuable predictors of cardiovascular and total morbidity and mortality in patients with a wide range of cardiovascular conditions is constantly increasing. Most studies that evaluated the influence of radiotherapy on the heart focused on left ventricular remodelling, which is why current guidelines only recommend detailed assessment of the left ventricle. Data regarding right ventricular changes in cancer patients treated with radiotherapy are scarce. Given that radiotherapy more often induces late cardiac impairment - unlike chemotherapy-induced cardiotoxicity, which is usually acute - it is quite reasonable to follow these patients echocardiographically for a long time (even for 20years after initiation of radiotherapy). Investigations that have followed cancer survivors for at least 10years after radiotherapy agree that right ventricular structure, systolic/diastolic function and mechanics are significantly impaired. The mechanisms of radiation-induced right ventricular remodelling are still unclear, but it is thought that fibrosis is the dominant factor in myocardial remodelling and vascular changes. Many factors may contribute to right ventricular impairment during and after radiotherapy: cumulative radiation dose; dose per treatment; delivery technique; radiation target (chest and mediastinum); and co-morbidities. In this review, we aim to provide a comprehensive overview of the potential mechanisms of radiation-induced right ventricular remodelling, and to summarize clinical studies involving radiotherapy-treated cancer patients.

  4. Identification of tumour-reactive lymphatic endothelial cells capable of inducing progression of gastric cancer

    PubMed Central

    Tokumoto, Mao Watanabe; Tanaka, Hiroaki; Tauchi, Yukie; Kasashima, Hiroaki; Kurata, Kento; Yashiro, Masakazu; Sakurai, Katsunobu; Toyokawa, Takahiro; Kubo, Naoshi; Amano, Ryosuke; Kimura, Kenjiro; Muguruma, Kazuya; Maeda, Kiyoshi; Ohira, Masaichi; Hirakawa, Kosei

    2015-01-01

    Background: Tumour cells and stromal cells interact in the tumour microenvironment; moreover, stromal cells can acquire abnormalities that contribute to tumour progression. However, interactions between lymphatic endothelial cells (LECs) and tumour cells are largely unexamined. In this study, we aimed to determine whether tumour-specific LECs inhabit the tumour microenvironment and examine their influence on this microenvironment. Methods: We isolated normal LECs (NLECs) from a non-metastatic lymph node and tumour-associated LECs (TLECs) from cancerous lymph nodes. We examined proliferative and migratory potency, growth factor production, and gene expression of each type of LEC. Moreover, we developed a co-culture system to investigate the interactions between gastric cancer cells and LECs. Results: When compared with NLEC, TLECs had an abnormal shape, high proliferative and migratory abilities, and elevated expression of genes associated with inflammation, cell growth, and cell migration. NLECs co-cultured with gastric cancer cells from the OCUM12 cell line acquired TLEC-like phenotypes. Also, OCUM12 cells co-cultured with TLECs expressed high levels of genes responsible for metastasis. Conclusions: Our results demonstrated that LECs interacted with tumour cells and obtained abnormal phenotypes that could have important roles in tumour progression. PMID:26355233

  5. Chromatin remodeller Fun30Fft3 induces nucleosome disassembly to facilitate RNA polymerase II elongation

    PubMed Central

    Lee, Junwoo; Shik Choi, Eun; David Seo, Hogyu; Kang, Keunsoo; Gilmore, Joshua M.; Florens, Laurence; Washburn, Michael P.; Choe, Joonho; Workman, Jerry L.; Lee, Daeyoup

    2017-01-01

    Previous studies have revealed that nucleosomes impede elongation of RNA polymerase II (RNAPII). Recent observations suggest a role for ATP-dependent chromatin remodellers in modulating this process, but direct in vivo evidence for this is unknown. Here using fission yeast, we identify Fun30Fft3 as a chromatin remodeller, which localizes at transcribing regions to promote RNAPII transcription. Fun30Fft3 associates with RNAPII and collaborates with the histone chaperone, FACT, which facilitates RNAPII elongation through chromatin, to induce nucleosome disassembly at transcribing regions during RNAPII transcription. Mutants, resulting in reduced nucleosome-barrier, such as deletion mutants of histones H3/H4 themselves and the genes encoding components of histone deacetylase Clr6 complex II suppress the defects in growth and RNAPII occupancy of cells lacking Fun30Fft3. These data suggest that RNAPII utilizes the chromatin remodeller, Fun30Fft3, to overcome the nucleosome barrier to transcription elongation. PMID:28218250

  6. Bile-induced peptidoglycan remodelling in Salmonella enterica.

    PubMed

    Hernández, Sara B; Cava, Felipe; Pucciarelli, M Graciela; García-Del Portillo, Francisco; de Pedro, Miguel A; Casadesús, Josep

    2015-04-01

    Changes in the peptidoglycan (PG) structure of Salmonella enterica are detected in the presence of a sublethal concentration of sodium deoxycholate (DOC): (i) lower proportions of Braun lipoprotein (Lpp)-bound muropeptides; (ii) reduced levels of muropeptides cross-linked by L(meso)-diaminopimelyl-D(meso)-diaminopimelic acid (L-D) peptide bridges (3-3 cross-links). Similar structural changes are found in S. enterica cultures adapted to grow in the presence of a lethal concentration of DOC, suggesting that reduced anchoring of Braun protein to PG and low occurrence of 3-3 cross-links may increase S. enterica resistance to bile. This view is further supported by additional observations: (i) A triple mutant lacking L,D-transpeptidases YbiS, ErfK, and YcfS, which does not contain Lpp anchored to PG, is hyper-resistant to bile; (ii) enhanced 3-3 cross-linking upon overexpression of YnhG transpeptidase causes a decrease in bile resistance. These observations suggest that remodelling of the cell wall may be added to the list of adaptive responses that permit survival of S. enterica in the presence of bile.

  7. Mechanical Stress Induces Remodeling of Vascular Networks in Growing Leaves.

    PubMed

    Bar-Sinai, Yohai; Julien, Jean-Daniel; Sharon, Eran; Armon, Shahaf; Nakayama, Naomi; Adda-Bedia, Mokhtar; Boudaoud, Arezki

    2016-04-01

    Differentiation into well-defined patterns and tissue growth are recognized as key processes in organismal development. However, it is unclear whether patterns are passively, homogeneously dilated by growth or whether they remodel during tissue expansion. Leaf vascular networks are well-fitted to investigate this issue, since leaves are approximately two-dimensional and grow manyfold in size. Here we study experimentally and computationally how vein patterns affect growth. We first model the growing vasculature as a network of viscoelastic rods and consider its response to external mechanical stress. We use the so-called texture tensor to quantify the local network geometry and reveal that growth is heterogeneous, resembling non-affine deformations in composite materials. We then apply mechanical forces to growing leaves after veins have differentiated, which respond by anisotropic growth and reorientation of the network in the direction of external stress. External mechanical stress appears to make growth more homogeneous, in contrast with the model with viscoelastic rods. However, we reconcile the model with experimental data by incorporating randomness in rod thickness and a threshold in the rod growth law, making the rods viscoelastoplastic. Altogether, we show that the higher stiffness of veins leads to their reorientation along external forces, along with a reduction in growth heterogeneity. This process may lead to the reinforcement of leaves against mechanical stress. More generally, our work contributes to a framework whereby growth and patterns are coordinated through the differences in mechanical properties between cell types.

  8. Mechanical Stress Induces Remodeling of Vascular Networks in Growing Leaves

    PubMed Central

    Bar-Sinai, Yohai; Julien, Jean-Daniel; Sharon, Eran; Armon, Shahaf; Nakayama, Naomi; Adda-Bedia, Mokhtar; Boudaoud, Arezki

    2016-01-01

    Differentiation into well-defined patterns and tissue growth are recognized as key processes in organismal development. However, it is unclear whether patterns are passively, homogeneously dilated by growth or whether they remodel during tissue expansion. Leaf vascular networks are well-fitted to investigate this issue, since leaves are approximately two-dimensional and grow manyfold in size. Here we study experimentally and computationally how vein patterns affect growth. We first model the growing vasculature as a network of viscoelastic rods and consider its response to external mechanical stress. We use the so-called texture tensor to quantify the local network geometry and reveal that growth is heterogeneous, resembling non-affine deformations in composite materials. We then apply mechanical forces to growing leaves after veins have differentiated, which respond by anisotropic growth and reorientation of the network in the direction of external stress. External mechanical stress appears to make growth more homogeneous, in contrast with the model with viscoelastic rods. However, we reconcile the model with experimental data by incorporating randomness in rod thickness and a threshold in the rod growth law, making the rods viscoelastoplastic. Altogether, we show that the higher stiffness of veins leads to their reorientation along external forces, along with a reduction in growth heterogeneity. This process may lead to the reinforcement of leaves against mechanical stress. More generally, our work contributes to a framework whereby growth and patterns are coordinated through the differences in mechanical properties between cell types. PMID:27074136

  9. Role of lymphatic vasculature in regional and distant metastases.

    PubMed

    Podgrabinska, Simona; Skobe, Mihaela

    2014-09-01

    In cancer, lymphatic vasculature has been traditionally viewed only as a transportation system for metastatic cells. It has now become clear that lymphatics perform many additional functions which could influence cancer progression. Lymphangiogenesis, induced at the primary tumor site and at distant sites, potently augments metastasis. Lymphatic endothelial cells (LECs) control tumor cell entry and exit from the lymphatic vessels. LECs also control immune cell traffic and directly modulate adaptive immune responses. This review highlights advances in our understanding of the mechanisms by which lymphatic vessels, and in particular lymphatic endothelium, impact metastasis. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Quantitative Imaging of Enzymatic Vitreolysis-Induced Fiber Remodeling

    PubMed Central

    Filas, Benjamen A.; Shah, Nihar S.; Zhang, Qianru; Shui, Ying-Bo; Lake, Spencer P.; Beebe, David C.

    2014-01-01

    Purpose. Collagen fiber remodeling in the vitreous body has been implicated in cases of vitreomacular traction, macular hole, and retinal detachment, and also may occur during pharmacologic vitreolysis. The purpose of this study was to evaluate quantitative polarized light imaging (QPLI) as a tool for studying fiber organization in the vitreous and near the vitreoretinal interface in control and enzymatically perturbed conditions. Methods. Fiber alignment was measured in anterior-posterior sections of bovine and porcine vitreous. Additional tests were performed on bovine lenses and nasal-temporal vitreous sections. Effects of proteoglycan degradation on collagen fiber alignment using trypsin and plasmin were assessed at the microstructural level using electron microscopy and at the global level using QPLI. Results. Control vitreous showed fiber organization patterns consistent with the literature across multiple-length scales, including the global anterior-posterior coursing of vitreous fibers, as well as local fibers parallel to the equatorial vitreoretinal interface and transverse to the posterior interface. Proteoglycan digestion with trypsin or plasmin significantly increased fiber alignment throughout the vitreous (P < 0.01). The largest changes (3×) occurred in the posterior vitreous where fibers are aligned transverse to the posterior vitreoretinal interface (P < 0.01). Conclusions. Proteoglycan loss due to enzymatic vitreolysis differentially increases fiber alignment at locations where tractions are most common. We hypothesize that a similar mechanism leads to retinal complications during age-related vitreous degeneration. Structural changes to the entire vitreous body (as opposed to the vitreoretinal interface alone) should be evaluated during preclinical testing of pharmacological vitreolysis candidates. PMID:25468895

  11. Effect of Brain-Derived Neurotrophic Factor Haploinsufficiency on Stress-Induced Remodeling of Hippocampal Neurons

    PubMed Central

    Magariños, A.M.; Li, C.J.; Toth, J. Gal; Bath, K.G.; Jing, D.; Lee, F.S.; McEwen, B.S.

    2010-01-01

    Chronic restraint stress (CRS) induces the remodeling (i.e., retraction and simplification) of the apical dendrites of hippocampal CA3 pyramidal neurons in rats, suggesting that intrahippocampal connectivity can be affected by a prolonged stressful challenge. Since the structural maintenance of neuronal dendritic arborizations and synaptic connectivity requires neurotrophic support, we investigated the potential role of brain derived neurotrophic factor (BDNF), a neurotrophin enriched in the hippocampus and released from neurons in an activity-dependent manner, as a mediator of the stress-induced dendritic remodeling. The analysis of Golgi-impregnated hippocampal sections revealed that wild type (WT) C57BL/6 male mice showed a similar CA3 apical dendritic remodeling in response to three weeks of CRS to that previously described for rats. Haploinsufficient BDNF mice (BDNF±) did not show such remodeling, but, even without CRS, they presented shorter and simplified CA3 apical dendritic arbors, like those observed in stressed WT mice. Furthermore, unstressed BDNF± mice showed a significant decrease in total hippocampal volume. The dendritic arborization of CA1 pyramidal neurons was not affected by CRS or genotype. However, only in WT mice, CRS induced changes in the density of dendritic spine shape subtypes in both CA1 and CA3 apical dendrites. These results suggest a complex role of BDNF in maintaining the dendritic and spine morphology of hippocampal neurons and the associated volume of the hippocampal formation. The inability of CRS to modify the dendritic structure of CA3 pyramidal neurons in BDNF± mice suggests an indirect, perhaps permissive, role of BDNF in mediating hippocampal dendritic remodeling. PMID:20095008

  12. Effect of brain-derived neurotrophic factor haploinsufficiency on stress-induced remodeling of hippocampal neurons.

    PubMed

    Magariños, A M; Li, C J; Gal Toth, J; Bath, K G; Jing, D; Lee, F S; McEwen, B S

    2011-03-01

    Chronic restraint stress (CRS) induces the remodeling (i.e., retraction and simplification) of the apical dendrites of hippocampal CA3 pyramidal neurons in rats, suggesting that intrahippocampal connectivity can be affected by a prolonged stressful challenge. Since the structural maintenance of neuronal dendritic arborizations and synaptic connectivity requires neurotrophic support, we investigated the potential role of brain derived neurotrophic factor (BDNF), a neurotrophin enriched in the hippocampus and released from neurons in an activity-dependent manner, as a mediator of the stress-induced dendritic remodeling. The analysis of Golgi-impregnated hippocampal sections revealed that wild type (WT) C57BL/6 male mice showed a similar CA3 apical dendritic remodeling in response to three weeks of CRS to that previously described for rats. Haploinsufficient BDNF mice (BDNF(±) ) did not show such remodeling, but, even without CRS, they presented shorter and simplified CA3 apical dendritic arbors, like those observed in stressed WT mice. Furthermore, unstressed BDNF(±) mice showed a significant decrease in total hippocampal volume. The dendritic arborization of CA1 pyramidal neurons was not affected by CRS or genotype. However, only in WT mice, CRS induced changes in the density of dendritic spine shape subtypes in both CA1 and CA3 apical dendrites. These results suggest a complex role of BDNF in maintaining the dendritic and spine morphology of hippocampal neurons and the associated volume of the hippocampal formation. The inability of CRS to modify the dendritic structure of CA3 pyramidal neurons in BDNF(±) mice suggests an indirect, perhaps permissive, role of BDNF in mediating hippocampal dendritic remodeling.

  13. Adventitial gene transfer of catalase attenuates angiotensin II-induced vascular remodeling.

    PubMed

    Liu, Cun-Fei; Zhang, Jia; Shen, Kai; Gao, Ping-Jin; Wang, Hai-Ya; Jin, Xin; Meng, Chao; Fang, Ning-Yuan

    2015-04-01

    Vascular adventitia and adventitia‑derived reactive oxygen species (ROS) contribute to vascular remodeling following vascular injury. A previous ex vivo study in adventitial fibroblasts showed that catalase, one of most important anti‑oxide enzymes, was downregulated by angiotensin II (AngII). The aim of the present study was to investigate whether adventitial gene transfer of catalase affects AngII‑induced vascular remodeling in vivo. Adenoviruses co‑expressing catalase and enhanced green fluorescent protein (eGFP) or expressing eGFP only were applied to the adventitial surface of common carotid arteries of Sprague‑Dawley rats. Alzet minipumps administering AngII (0.75 mg/kg/day) were then implanted subcutaneously for 14 days. Systolic blood pressure and biological parameters of vascular remodeling were measured in each group. Adventitial fibroblasts were cultured and p38 mitogen‑activated protein kinase (MAPK) phosphorylation was measured using western blot analysis. The results showed that adventitial gene transfer of catalase had no effect on AngII‑induced systolic blood pressure elevation. However, catalase adenovirus transfection significantly inhibited AngII‑induced media hypertrophy compared with that of the control virus (P<0.05). In addition, catalase transfection significantly attenuated AngII‑induced ROS generation, macrophage infiltration, collagen deposition and adventitial α‑smooth muscle actin expression. Furthermore, catalase transfection significantly inhibited the AngII‑induced increase in p38MAPK phosphorylation. In conclusion, the results of the present study demonstrated that adventitial gene transfer of catalase significantly attenuated AngII‑induced vascular remodeling in rats via inhibition of adventitial p38MAPK phosphorylation.

  14. Membrane remodeling, an early event in benzo[alpha]pyrene-induced apoptosis

    SciTech Connect

    Tekpli, Xavier; Rissel, Mary; Huc, Laurence; Catheline, Daniel; Sergent, Odile; Rioux, Vincent; Legrand, Philippe; Holme, Jorn A.; Dimanche-Boitrel, Marie-Therese; Lagadic-Gossmann, Dominique

    2010-02-15

    Benzo[alpha]pyrene (B[alpha]P) often serves as a model for mutagenic and carcinogenic polycyclic aromatic hydrocarbons (PAHs). Our previous work suggested a role of membrane fluidity in B[alpha]P-induced apoptotic process. In this study, we report that B[alpha]P modifies the composition of cholesterol-rich microdomains (lipid rafts) in rat liver F258 epithelial cells. The cellular distribution of the ganglioside-GM1 was markedly changed following B[alpha]P exposure. B[alpha]P also modified fatty acid composition and decreased the cholesterol content of cholesterol-rich microdomains. B[alpha]P-induced depletion of cholesterol in lipid rafts was linked to a reduced expression of 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-CoA reductase). Aryl hydrocarbon receptor (AhR) and B[alpha]P-related H{sub 2}O{sub 2} formation were involved in the reduced expression of HMG-CoA reductase and in the remodeling of membrane microdomains. The B[alpha]P-induced membrane remodeling resulted in an intracellular alkalinization observed during the early phase of apoptosis. In conclusion, B[alpha]P altered the composition of plasma membrane microstructures through AhR and H{sub 2}O{sub 2} dependent-regulation of lipid biosynthesis. In F258 cells, the B[alpha]P-induced membrane remodeling was identified as an early apoptotic event leading to an intracellular alkalinization.

  15. Lung Extracellular Superoxide Dismutase Overexpression Lessens Bleomycin-Induced Pulmonary Hypertension and Vascular Remodeling

    PubMed Central

    Van Rheen, Zachary; Fattman, Cheryl; Domarski, Shannon; Majka, Susan; Klemm, Dwight; Stenmark, Kurt R.; Nozik-Grayck, Eva

    2011-01-01

    Interstitial lung disease is a devastating disease in humans that can be further complicated by the development of secondary pulmonary hypertension. Accumulating evidence indicates that the oxidant superoxide can contribute to the pathogenesis of both interstitial lung disease and pulmonary hypertension. We used a model of pulmonary hypertension secondary to bleomycin-induced pulmonary fibrosis to test the hypothesis that an imbalance in extracellular superoxide and its antioxidant defense, extracellular superoxide dismutase, will promote pulmonary vascular remodeling and pulmonary hypertension. We exposed transgenic mice overexpressing lung extracellular superoxide dismutase and wild-type littermates to a single dose of intratracheal bleomycin, and evaluated the mice weekly for up to 35 days. We assessed pulmonary vascular remodeling and the expression of several genes critical to lung fibrosis, as well as pulmonary hypertension and mortality. The overexpression of extracellular superoxide dismutase protected against late remodeling within the medial, adventitial, and intimal layers of the vessel wall after the administration of bleomycin, and attenuated pulmonary hypertension at the same late time point. The overexpression of extracellular superoxide dismutase also blocked the early up-regulation of two key genes in the lung known to be critical in pulmonary fibrosis and vascular remodeling, the transcription factor early growth response–1 and transforming growth factor–β. The overexpression of extracellular superoxide dismutase attenuated late pulmonary hypertension and significantly improved survival after exposure to bleomycin. These data indicate an important role for an extracellular oxidant/antioxidant imbalance in the pathogenesis of pulmonary vascular remodeling associated with secondary pulmonary hypertension attributable to bleomycin-induced lung fibrosis. PMID:20539010

  16. Quantification of Protein-Induced Membrane Remodeling Kinetics In Vitro with Lipid Multilayer Gratings.

    PubMed

    Lowry, Troy W; Hariri, Hanaa; Prommapan, Plengchart; Kusi-Appiah, Aubrey; Vafai, Nicholas; Bienkiewicz, Ewa A; Van Winkle, David H; Stagg, Scott M; Lenhert, Steven

    2016-01-27

    The dynamic self-organization of lipids in biological systems is a highly regulated process that enables the compartmentalization of living systems at micro- and nanoscopic scales. Consequently, quantitative methods for assaying the kinetics of supramolecular remodeling such as vesicle formation from planar lipid bilayers or multilayers are needed to understand cellular self-organization. Here, a new nanotechnology-based method for quantitative measurements of lipid-protein interactions is presented and its suitability for quantifying the membrane binding, inflation, and budding activity of the membrane-remodeling protein Sar1 is demonstrated. Lipid multilayer gratings are printed onto surfaces using nanointaglio and exposed to Sar1, resulting in the inflation of lipid multilayers into unilamellar structures, which can be observed in a label-free manner by monitoring the diffracted light. Local variations in lipid multilayer volume on the surface is used to vary substrate availability in a microarray format. A quantitative model is developed that allows quantification of binding affinity (K D ) and kinetics (kon and koff ). Importantly, this assay is uniquely capable of quantifying membrane remodeling. Upon Sar1-induced inflation of single bilayers from surface supported multilayers, the semicylindrical grating lines are observed to remodel into semispherical buds when a critical radius of curvature is reached.

  17. Quantification of Protein-Induced Membrane Remodeling Kinetics In Vitro with Lipid Multilayer Gratings

    PubMed Central

    Lowry, Troy W.; Hariri, Hanaa; Prommapan, Plengchart; Kusi-Appiah, Aubrey; Vafai, Nicholas; Bienkiewicz, Ewa A.; Van Winkle, David H.; Stagg, Scott M.

    2016-01-01

    The dynamic self-organization of lipids in biological systems is a highly regulated process that enables the compartmentalization of living systems at micro- and nanoscopic scales. Consequently, quantitative methods for assaying the kinetics of supramolecular remodeling such as vesicle formation from planar lipid bilayers or multilayers are needed to understand cellular self-organization. Here, a new nanotechnology-based method for quantitative measurements of lipid–protein interactions is presented and its suitability for quantifying the membrane binding, inflation, and budding activity of the membrane-remodeling protein Sar1 is demonstrated. Lipid multilayer gratings are printed onto surfaces using nanointaglio and exposed to Sar1, resulting in the inflation of lipid multilayers into unilamellar structures, which can be observed in a label-free manner by monitoring the diffracted light. Local variations in lipid multilayer volume on the surface is used to vary substrate availability in a microarray format. A quantitative model is developed that allows quantification of binding affinity (KD) and kinetics (kon and koff). Importantly, this assay is uniquely capable of quantifying membrane remodeling. Upon Sar1-induced inflation of single bilayers from surface supported multilayers, the semicylindrical grating lines are observed to remodel into semispherical buds when a critical radius of curvature is reached. PMID:26649649

  18. Long Noncoding RNA-GAS5: A Novel Regulator of Hypertension-Induced Vascular Remodeling.

    PubMed

    Wang, Yang-Ning-Zhi; Shan, Kun; Yao, Mu-Di; Yao, Jin; Wang, Jia-Jian; Li, Xiang; Liu, Ban; Zhang, Yang-Yang; Ji, Yong; Jiang, Qin; Yan, Biao

    2016-09-01

    Vascular remodeling is an important pathological feature of hypertension, leading to increased vascular resistance and reduced compliance. Endothelial cell (EC) and vascular smooth muscle cell (VSMC) dysfunction is involved in vascular remodeling. Long noncoding RNAs are potential regulators of EC and VSMC function. Herein, we determined whether long noncoding RNA-growth arrest-specific 5 (GAS5) is involved in hypertension-related vascular remodeling. We revealed that GAS5 knockdown aggravated hypertension-induced microvascular dysfunction as shown by increased retinal neovascularization and capillary leakage. GAS5 regulated the remodeling of arteries, including caudal arteries, carotid arteries, renal arteries, and thoracic arteries. GAS5 was mainly expressed in ECs and VSMCs, and its expression was significantly downregulated in hypertension. GAS5 knockdown affected endothelial activation, endothelial proliferation, VSMC phenotypic conversion, and EC-VSMC communication in vivo and in vitro. Mechanistically, GAS5 regulated EC and VSMC function through β-catenin signaling. This study identified GAS5 as a critical regulator in hypertension and demonstrated the potential of gene therapy and drug development for treating hypertension. © 2016 American Heart Association, Inc.

  19. Impact of family hypertension history on exercise-induced cardiac remodeling.

    PubMed

    Baggish, Aaron L; Weiner, Rory B; Yared, Kibar; Wang, Francis; Kupperman, Eli; Hutter, Adolph M; Picard, Michael H; Wood, Malissa J

    2009-07-01

    Left ventricular (LV) hypertrophy is a well-established, but highly variable, finding among exercise-trained persons. The causes for the variability in LV remodeling in response to exercise training remain incompletely understood. The present study sought to determine whether a family history of hypertension is a determinant of the cardiac response to exercise training. The cardiac parameters in 60 collegiate rowers (30 men/30 women; age 19.8 +/- 1.1 years) with (family history positive [FH+], n = 22) and without (family history negative [FH-], n = 38) a FH of hypertension were studied with echocardiography before and after 90 days of rowing training. The LV mass increased significantly in both groups. However, the LV mass increased significantly more in FH- persons (Delta 17 +/- 5 g/m(2)) than in FH+ persons (Delta 9 +/- 6 g/m(2), p <0.001) with distinctly differently patterns of LV hypertrophy between the 2 groups. FH- athletes experienced eccentric LV hypertrophy (relative wall thickness index 0.39 +/- 0.4) characterized by LV dilation. In contrast, FH+ athletes developed concentric LV hypertrophy (relative wall thickness index 0.44 +/- 0.3; p <0.001) characterized by LV wall thickening. Furthermore, the eccentric LV remodeling in FH- athletes was associated with a more robust enhancement of LV diastolic function than the concentric LV remodeling that occurred in FH+ athletes. In conclusion, these findings suggest that patterns of exercise-induced LV remodeling are strongly associated with FH history status.

  20. Remodeling of the Mandibular Bone Induced by Overdentures Supported by Different Numbers of Implants.

    PubMed

    Li, Kai; Xin, Haitao; Zhao, Yanfang; Zhang, Zhiyuan; Wu, Yulu

    2016-05-01

    The objective of this study was to investigate the process of mandibular bone remodeling induced by implant-supported overdentures. computed tomography (CT) images were collected from edentulous patients to reconstruct the geometry of the mandibular bone and overdentures supported by implants. Based on the theory of strain energy density (SED), bone remodeling models were established using the user material subroutine (UMAT) in abaqus. The stress distribution in the mandible and bone density change was investigated to determine the effect of implant number on the remodeling of the mandibular bone. The results indicated that the areas where high Mises stress values were observed were mainly situated around the implants. The stress was concentrated in the distal neck region of the distal-most implants. With an increased number of implants, the biting force applied on the dentures was almost all taken up by implants. The stress and bone density in peri-implant bone increased. When the stress reached the threshold of remodeling, the bone density began to decrease. In the posterior mandible area, the stress was well distributed but increased with decreased implant numbers. Changes in bone density were not observed in this area. The computational results were consistent with the clinical data. The results demonstrate that the risk of bone resorption around the distal-most implants increases with increased numbers of implants and that the occlusal force applied to overdentures should be adjusted to be distributed more in the distal areas of the mandible.

  1. ACF chromatin remodeling complex mediates stress–induced depressive–like behavior

    PubMed Central

    Sun, HaoSheng; Damez–Werno, Diane M.; Scobie, Kimberly N.; Shao, Ning–Yi; Dias, Caroline; Rabkin, Jacqui; Koo, Ja Wook; Korb, Erica; Bagot, Rosemary C.; Ahn, Francisca H.; Cahill, Michael E.; Labonté, Benoit; Mouzon, Ezekiell; Heller, Elizabeth A.; Cates, Hannah; Golden, Sam A; Gleason, Kelly; Russo, Scott J; Andrews, Simon; Neve, Rachael; Kennedy, Pamela J.; Maze, Ian; Dietz, David M.; Allis, C. David; Turecki, Gustavo; Varga–Weisz, Patrick; Tamminga, Carol; Shen, Li; Nestler, Eric J.

    2015-01-01

    Improved treatment for major depressive disorder (MDD) remains elusive due to limited understanding of its underlying biological mechanisms. Stress–induced maladaptive transcriptional regulation within limbic neural circuits likely contributes to the development of MDD, possibly through epigenetic factors that regulate chromatin structure. We establish that persistent upregulation of the ACF ATP–dependent chromatin remodeling complex, occurring in the nucleus accumbens of stress–susceptible mice and depressed humans, is necessary for stress–induced depressive–like behaviors. Altered ACF binding after chronic stress is correlated with altered nucleosome positioning, particularly around the transcription start sites of affected genes. These alterations in ACF binding and nucleosome positioning are associated with repressed expression of genes implicated in susceptibility to stress. Together, we identify the ACF chromatin remodeling complex as a critical component in the development of susceptibility to depression and in regulating stress–related behaviors. PMID:26390241

  2. Smooth Muscle Tension Induces Invasive Remodeling of the Zebrafish Intestine

    PubMed Central

    Seiler, Christoph; Davuluri, Gangarao; Abrams, Joshua; Byfield, Fitzroy J.; Janmey, Paul A.; Pack, Michael

    2012-01-01

    The signals that initiate cell invasion are not well understood, but there is increasing evidence that extracellular physical signals play an important role. Here we show that epithelial cell invasion in the intestine of zebrafish meltdown (mlt) mutants arises in response to unregulated contractile tone in the surrounding smooth muscle cell layer. Physical signaling in mlt drives formation of membrane protrusions within the epithelium that resemble invadopodia, matrix-degrading protrusions present in invasive cancer cells. Knockdown of Tks5, a Src substrate that is required for invadopodia formation in mammalian cells blocked formation of the protrusions and rescued invasion in mlt. Activation of Src-signaling induced invadopodia-like protrusions in wild type epithelial cells, however the cells did not migrate into the tissue stroma, thus indicating that the protrusions were required but not sufficient for invasion in this in vivo model. Transcriptional profiling experiments showed that genes responsive to reactive oxygen species (ROS) were upregulated in mlt larvae. ROS generators induced invadopodia-like protrusions and invasion in heterozygous mlt larvae but had no effect in wild type larvae. Co-activation of oncogenic Ras and Wnt signaling enhanced the responsiveness of mlt heterozygotes to the ROS generators. These findings present the first direct evidence that invadopodia play a role in tissue cell invasion in vivo. In addition, they identify an inducible physical signaling pathway sensitive to redox and oncogenic signaling that can drive this process. PMID:22973180

  3. Mechanism of Tissue Remodeling in Sepsis-Induced Acute Lung Injury

    DTIC Science & Technology

    2006-04-01

    identified (e.g., infection, trauma ), little is known about the factors that control the tissue remodeling response. This project addresses this very...induced fibronectin expression in fibroblasts. This suggests that the main player in this process is acetaldehyde . To test this, we exposed cells...to acetaldehyde and found that this molecule indeed stimulated fibronectin expression. The latter observation suggests that lung fibroblasts contain

  4. Angiotensin-II Induced Hypertension and Renovascular Remodeling in TIMP2 Knockout Mice

    PubMed Central

    PUSHPAKUMAR, Sathnur; KUNDU, Sourav; PRYOR, Tyranny; GIVVIMANI, Srikanth; LEDERER, Eleanor; TYAGI, Suresh C.; SEN, Utpal

    2014-01-01

    Sustained hypertension induces renovascular remodeling by altering extracellular matrix (ECM) components. Matrix metalloproteinases (MMPs) are Zn-dependent enzymes that regulate ECM turnover in concert with their inhibitors, tissue inhibitors of metalloproteinases, TIMPs. Increased MMP-2 & -9 have been implicated in hypertensive complications; however, the contribution of individual MMPs/TIMPs in renal remodeling has not been fully elucidated. The purpose of this study was to determine the effect of TIMP2 deficiency and thus MMP-2 on Ang-II induced renal remodeling. C57BL/6J (WT) and TIMP2 knockout mice were infused with Angiotensin-II (Ang-II) at 250 ng. kg-1. min-1 for 4 weeks. Blood pressure was measured weekly and end-point laser Doppler flowmetry was done to assess cortical blood flow. Immunohistochemical staining was performed for collagen and elastin analyses. The activity of MMP-9, and -2 was determined by Gelatin zymography. Ang-II induced similar elevation in mean blood pressure in TIMP2-/- and WT mice. In TIMP2-/- mice, Ang-II treatment was associated with a greater reduction in renal cortical blood flow and barium angiography demonstrated decreased vascular density compared to Ang-II treated WT mice. Peri-glomerular and vascular collagen deposition was increased and elastin content was decreased causing increased wall-to-lumen ratio in TIMP2-/- mice compared to WT mice receiving Ang-II. Ang-II increased the expression and activity of MMP-9 predominantly in TIMP2-/- mice than in WT mice. These results suggest that TIMP2 deficiency exacerbates renovascular remodeling in agonist induced hypertension by a mechanism which may, in part, be attributed to increased activity of MMP-9. PMID:24077247

  5. Aberrant mural cell recruitment to lymphatic vessels and impaired lymphatic drainage in a murine model of pulmonary fibrosis.

    PubMed

    Meinecke, Anna-Katharina; Nagy, Nadine; Lago, Gabriela D'Amico; Kirmse, Santina; Klose, Ralph; Schrödter, Katrin; Zimmermann, Annika; Helfrich, Iris; Rundqvist, Helene; Theegarten, Dirk; Anhenn, Olaf; Orian-Rousseau, Véronique; Johnson, Randall S; Alitalo, Kari; Fischer, Jens W; Fandrey, Joachim; Stockmann, Christian

    2012-06-14

    Pulmonary fibrosis is a progressive disease with unknown etiology that is characterized by extensive remodeling of the lung parenchyma, ultimately resulting in respiratory failure. Lymphatic vessels have been implicated with the development of pulmonary fibrosis, but the role of the lymphatic vasculature in the pathogenesis of pulmonary fibrosis remains enigmatic. Here we show in a murine model of pulmonary fibrosis that lymphatic vessels exhibit ectopic mural coverage and that this occurs early during the disease. The abnormal lymphatic vascular patterning in fibrotic lungs was driven by expression of platelet-derived growth factor B (PDGF-B) in lymphatic endothelial cells and signaling through platelet-derived growth factor receptor (PDGFR)-β in associated mural cells. Because of impaired lymphatic drainage, aberrant mural cell coverage fostered the accumulation of fibrogenic molecules and the attraction of fibroblasts to the perilymphatic space. Pharmacologic inhibition of the PDGF-B/PDGFR-β signaling axis disrupted the association of mural cells and lymphatic vessels, improved lymphatic drainage of the lung, and prevented the attraction of fibroblasts to the perilymphatic space. Our results implicate aberrant mural cell recruitment to lymphatic vessels in the pathogenesis of pulmonary fibrosis and that the drainage capacity of pulmonary lymphatics is a critical mediator of fibroproliferative changes.

  6. Exercise training improves obesity-related lymphatic dysfunction.

    PubMed

    Hespe, Geoffrey E; Kataru, Raghu P; Savetsky, Ira L; García Nores, Gabriela D; Torrisi, Jeremy S; Nitti, Matthew D; Gardenier, Jason C; Zhou, Jie; Yu, Jessie Z; Jones, Lee W; Mehrara, Babak J

    2016-08-01

    Obesity results in perilymphatic inflammation and lymphatic dysfunction. Lymphatic dysfunction in obesity is characterized by decreased lymphatic vessel density, decreased collecting lymphatic vessel pumping frequency, decreased lymphatic trafficking of immune cells, increased lymphatic vessel leakiness and changes in the gene expression patterns of lymphatic endothelial cells. Aerobic exercise, independent of weight loss, decreases perilymphatic inflammatory cell accumulation, improves lymphatic function and reverses pathological changes in gene expression in lymphatic endothelial cells. Although previous studies have shown that obesity markedly decreases lymphatic function, the cellular mechanisms that regulate this response remain unknown. In addition, it is unclear whether the pathological effects of obesity on the lymphatic system are reversible with behavioural modifications. The purpose of this study, therefore, was to analyse lymphatic vascular changes in obese mice and to determine whether these pathological effects are reversible with aerobic exercise. We randomized obese mice to either aerobic exercise (treadmill running for 30 min per day, 5 days a week, for 6 weeks) or a sedentary group that was not exercised and analysed lymphatic function using a variety of outcomes. We found that sedentary obese mice had markedly decreased collecting lymphatic vessel pumping capacity, decreased lymphatic vessel density, decreased lymphatic migration of immune cells, increased lymphatic vessel leakiness and decreased expression of lymphatic specific markers compared with lean mice (all P < 0.01). Aerobic exercise did not cause weight loss but markedly improved lymphatic function compared with sedentary obese mice. Exercise had a significant anti-inflammatory effect, resulting in decreased perilymphatic accumulation of inflammatory cells and inducible nitric oxide synthase expression. In addition, exercise normalized isolated lymphatic endothelial cell gene

  7. Changes in mitochondrial morphology induced by calcium or rotenone in primary astrocytes occur predominantly through ros-mediated remodeling.

    PubMed

    Deheshi, Samineh; Dabiri, Bahram; Fan, Susu; Tsang, Michelle; Rintoul, Gordon L

    2015-06-01

    Morphological changes in mitochondria have been primarily attributed to fission and fusion, while the more pliable transformations of mitochondria (remodeling, rounding, or stretching) have been largely overlooked. In this study, we quantify the contributions of fission and remodeling to changes in mitochondrial morphology induced by the Ca(2+) ionophore 4Br-A23187 and the metabolic toxin rotenone. We also examine the role of reactive oxygen species (ROS) in the regulation of mitochondrial remodeling. In agreement with our previous studies, mitochondrial remodeling, not fission, is the primary contributor to Ca(2+) -mediated changes in mitochondrial morphology induced by 4Br-A23187 in rat cortical astrocytes. Treatment with rotenone produced similar results. In both paradigms, remodeling was selectively blocked by antioxidants whereas fission was not, suggesting a ROS-mediated mechanism for mitochondrial remodeling. In support of this hypothesis, inhibition of endogenous ROS by overnight incubation in antioxidants resulted in elongated reticular networks of mitochondria. Examination of inner and outer mitochondrial membranes revealed that they largely acted in concert during the remodeling process. While mitochondrial morphology is traditionally ascribed to a net output of fission and fusion processes, in this study we provide evidence that the acute pliability of mitochondria can be a dominant factor in determining their morphology. More importantly, our results suggest that the remodeling process is independently regulated through a ROS-signaling mechanism. Mitochondrial morphology is traditionally ascribed to a balance of fission and fusion processes. We have shown that mitochondria can undergo more pliable transformations; remodeling, rounding, or stretching. We demonstrate that remodeling, not fission, is the primary contributor to calcium mediated changes in mitochondrial morphology in primary astrocytes. Others have shown fission is mediated by calcineurin

  8. A Food-Derived Flavonoid Luteolin Protects against Angiotensin II-Induced Cardiac Remodeling.

    PubMed

    Nakayama, Atsuko; Morita, Hiroyuki; Nakao, Tomoko; Yamaguchi, Toshihiro; Sumida, Tomokazu; Ikeda, Yuichi; Kumagai, Hidetoshi; Motozawa, Yoshihiro; Takahashi, Tsukasa; Imaizumi, Atsushi; Hashimoto, Tadashi; Nagai, Ryozo; Komuro, Issei

    2015-01-01

    Oxidative stress has been implicated in cardiac remodeling (cardiac fibrosis and hypertrophy), which impairs cardiac function and metabolism; therefore, it is anticipated antioxidative compounds will have protective properties against cardiac remodeling. Luteolin (3',4',5,7-tetrahydroxyflavone), a widely distributed flavonoid found in many herbal extracts including celery, green pepper, perilla leaves and seeds, and chamomile, is a known to be a potent antioxidant and was previously demonstrated to exert an antifibrotic effect in the lungs and the liver. In this study, we clearly demonstrate that oral pretreatment with the higher-luteolin diet (0.035% (wt/wt)) protected against cardiac fibrosis and hypertrophy as well as a hyperoxidative state in Ang II-infused rats. In cardiac tissue, increased gene expression levels of TGFβ1, CTGF, Nox2, Nox4, ANP, and BNP induced by Ang II were restored by oral pretreatment of this high-luteolin diet. In cultured rat cardiac fibroblasts, H2O2-induced TGFβ1 expression and the phosphorylation of JNK were suppressed by luteolin pretreatment. In conclusion, food-derived luteolin has protective actions against Ang II-induced cardiac remodeling, which could be mediated through attenuation of oxidative stress.

  9. A Food-Derived Flavonoid Luteolin Protects against Angiotensin II-Induced Cardiac Remodeling

    PubMed Central

    Nakao, Tomoko; Yamaguchi, Toshihiro; Sumida, Tomokazu; Ikeda, Yuichi; Kumagai, Hidetoshi; Motozawa, Yoshihiro; Takahashi, Tsukasa; Imaizumi, Atsushi; Hashimoto, Tadashi; Nagai, Ryozo; Komuro, Issei

    2015-01-01

    Oxidative stress has been implicated in cardiac remodeling (cardiac fibrosis and hypertrophy), which impairs cardiac function and metabolism; therefore, it is anticipated antioxidative compounds will have protective properties against cardiac remodeling. Luteolin (3’,4’,5,7-tetrahydroxyflavone), a widely distributed flavonoid found in many herbal extracts including celery, green pepper, perilla leaves and seeds, and chamomile, is a known to be a potent antioxidant and was previously demonstrated to exert an antifibrotic effect in the lungs and the liver. In this study, we clearly demonstrate that oral pretreatment with the higher-luteolin diet (0.035% (wt/wt)) protected against cardiac fibrosis and hypertrophy as well as a hyperoxidative state in Ang II-infused rats. In cardiac tissue, increased gene expression levels of TGFβ1, CTGF, Nox2, Nox4, ANP, and BNP induced by Ang II were restored by oral pretreatment of this high-luteolin diet. In cultured rat cardiac fibroblasts, H2O2-induced TGFβ1 expression and the phosphorylation of JNK were suppressed by luteolin pretreatment. In conclusion, food-derived luteolin has protective actions against Ang II-induced cardiac remodeling, which could be mediated through attenuation of oxidative stress. PMID:26327560

  10. Lymphatic endothelial lineage assemblage during corneal lymphangiogenesis

    PubMed Central

    Connor, Alicia L.; Kelley, Philip M.; Tempero, Richard M.

    2015-01-01

    Post natal inflammatory lymphangiogenesis presumably requires precise regulatory processes to properly assemble proliferating lymphatic endothelial cells (LECs). The specific mechanisms that regulate the assembly of LECs during new lymphatic vessel synthesis are unclear. Dynamic endothelial shuffling and rearrangement has been proposed as a mechanism of blood vessel growth. We developed genetic lineage tracing strategies using an inductive transgenic technology to track the fate of entire tandem dimer tomato positive (tdT) lymphatic vessels or small, in some cases clonal, populations of LECs. We coupled this platform with a suture induced mouse model of corneal lymphangiogenesis and used different analytic microscopy techniques including serial live imaging to study the spatial properties of proliferating tdT+ LEC progenies. LEC precursors and their progeny expanded from the corneal limbal lymphatic vessel and were assembled contiguously to comprise a subunit within a new lymphatic vessel. VE-cadherin blockade induced morphologic abnormalities in newly synthesized lymphatic vessels, but did not disrupt the tdT+ lymphatic endothelial lineage assembly. Analysis of this static and dynamic data based largely on direct in vivo observations supports a model of lymphatic endothelial lineage assemblage during corneal inflammatory lymphangiogenesis. PMID:26658452

  11. Impaired mitochondrial fat oxidation induces adaptive remodeling of muscle metabolism.

    PubMed

    Wicks, Shawna E; Vandanmagsar, Bolormaa; Haynie, Kimberly R; Fuller, Scott E; Warfel, Jaycob D; Stephens, Jacqueline M; Wang, Miao; Han, Xianlin; Zhang, Jingying; Noland, Robert C; Mynatt, Randall L

    2015-06-23

    The correlations between intramyocellular lipid (IMCL), decreased fatty acid oxidation (FAO), and insulin resistance have led to the hypothesis that impaired FAO causes accumulation of lipotoxic intermediates that inhibit muscle insulin signaling. Using a skeletal muscle-specific carnitine palmitoyltransferase-1 KO model, we show that prolonged and severe mitochondrial FAO inhibition results in increased carbohydrate utilization, along with reduced physical activity; increased circulating nonesterified fatty acids; and increased IMCLs, diacylglycerols, and ceramides. Perhaps more importantly, inhibition of mitochondrial FAO also initiates a local, adaptive response in muscle that invokes mitochondrial biogenesis, compensatory peroxisomal fat oxidation, and amino acid catabolism. Loss of its major fuel source (lipid) induces an energy deprivation response in muscle coordinated by signaling through AMP-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) to maintain energy supply for locomotion and survival. At the whole-body level, these adaptations result in resistance to obesity.

  12. Impaired mitochondrial fat oxidation induces adaptive remodeling of muscle metabolism

    PubMed Central

    Wicks, Shawna E.; Vandanmagsar, Bolormaa; Haynie, Kimberly R.; Fuller, Scott E.; Warfel, Jaycob D.; Stephens, Jacqueline M.; Wang, Miao; Han, Xianlin; Zhang, Jingying; Noland, Robert C.; Mynatt, Randall L.

    2015-01-01

    The correlations between intramyocellular lipid (IMCL), decreased fatty acid oxidation (FAO), and insulin resistance have led to the hypothesis that impaired FAO causes accumulation of lipotoxic intermediates that inhibit muscle insulin signaling. Using a skeletal muscle-specific carnitine palmitoyltransferase-1 KO model, we show that prolonged and severe mitochondrial FAO inhibition results in increased carbohydrate utilization, along with reduced physical activity; increased circulating nonesterified fatty acids; and increased IMCLs, diacylglycerols, and ceramides. Perhaps more importantly, inhibition of mitochondrial FAO also initiates a local, adaptive response in muscle that invokes mitochondrial biogenesis, compensatory peroxisomal fat oxidation, and amino acid catabolism. Loss of its major fuel source (lipid) induces an energy deprivation response in muscle coordinated by signaling through AMP-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) to maintain energy supply for locomotion and survival. At the whole-body level, these adaptations result in resistance to obesity. PMID:26056297

  13. Simulated Microgravity and Recovery-Induced Remodeling of the Left and Right Ventricle

    PubMed Central

    Zhong, Guohui; Li, Yuheng; Li, Hongxing; Sun, Weijia; Cao, Dengchao; Li, Jianwei; Zhao, Dingsheng; Song, Jinping; Jin, Xiaoyan; Song, Hailin; Yuan, Xinxin; Wu, Xiaorui; Li, Qi; Xu, Qing; Kan, Guanghan; Cao, Hongqing; Ling, Shukuan; Li, Yingxian

    2016-01-01

    Physiological adaptations to microgravity involve alterations in cardiovascular systems. These adaptations result in cardiac remodeling and orthostatic hypotension. However, the response of the left ventricle (LV) and right ventricle (RV) following hindlimb unloading (HU) and hindlimb reloading (HR) is not clear and the underlying mechanism remains to be understood. In this study, three groups of mice were subjected to HU by tail suspension for 28 days. Following this, two groups were allowed to recover for 7 or 14 days. The control group was treated equally, with the exception of tail suspension. Echocardiography was performed to detect the structure and function changes of heart. Compared with the control, the HU group of mice showed reduced LV-EF (ejection fraction), and LV-FS (fractional shortening). However, mice that were allowed to recover for 7 days after HU (HR-7d) showed increased LVIDs (systolic LV internal diameter) and LV Vols (systolic LV volume). Mice that recovered for 14 days (HR-14d) returned to the normal state. In comparison, RV-EF and RV-FS didn't recover to the normal conditions till being reloaded for 14 days. Compared with the control, RVIDd (diastolic RV internal diameter), and RV Vold (diastolic RV volume) were reduced in HU group and recovered to the normal conditions in HR-7d and HR-14d groups, in which groups RVIDs (systolic RV internal diameter) and RV Vols (systolic RV volume) were increased. Histological analysis and cardiac remodeling gene expression results indicated that HU induces left and right ventricular remodeling. Western blot demonstrated that the phosphorylation of HDAC4 and ERK1/2 and the ratio of LC3-II / LC3-I, were increased following HU and recovered following HR in both LV and RV, and the phosphorylation of AMPK was inhibited in both LV and RV following HU, but only restored in LV following HR for 14 days. These results indicate that simulated microgravity leads to cardiac remodeling, and the remodeling changes can

  14. Simulated Microgravity and Recovery-Induced Remodeling of the Left and Right Ventricle.

    PubMed

    Zhong, Guohui; Li, Yuheng; Li, Hongxing; Sun, Weijia; Cao, Dengchao; Li, Jianwei; Zhao, Dingsheng; Song, Jinping; Jin, Xiaoyan; Song, Hailin; Yuan, Xinxin; Wu, Xiaorui; Li, Qi; Xu, Qing; Kan, Guanghan; Cao, Hongqing; Ling, Shukuan; Li, Yingxian

    2016-01-01

    Physiological adaptations to microgravity involve alterations in cardiovascular systems. These adaptations result in cardiac remodeling and orthostatic hypotension. However, the response of the left ventricle (LV) and right ventricle (RV) following hindlimb unloading (HU) and hindlimb reloading (HR) is not clear and the underlying mechanism remains to be understood. In this study, three groups of mice were subjected to HU by tail suspension for 28 days. Following this, two groups were allowed to recover for 7 or 14 days. The control group was treated equally, with the exception of tail suspension. Echocardiography was performed to detect the structure and function changes of heart. Compared with the control, the HU group of mice showed reduced LV-EF (ejection fraction), and LV-FS (fractional shortening). However, mice that were allowed to recover for 7 days after HU (HR-7d) showed increased LVIDs (systolic LV internal diameter) and LV Vols (systolic LV volume). Mice that recovered for 14 days (HR-14d) returned to the normal state. In comparison, RV-EF and RV-FS didn't recover to the normal conditions till being reloaded for 14 days. Compared with the control, RVIDd (diastolic RV internal diameter), and RV Vold (diastolic RV volume) were reduced in HU group and recovered to the normal conditions in HR-7d and HR-14d groups, in which groups RVIDs (systolic RV internal diameter) and RV Vols (systolic RV volume) were increased. Histological analysis and cardiac remodeling gene expression results indicated that HU induces left and right ventricular remodeling. Western blot demonstrated that the phosphorylation of HDAC4 and ERK1/2 and the ratio of LC3-II / LC3-I, were increased following HU and recovered following HR in both LV and RV, and the phosphorylation of AMPK was inhibited in both LV and RV following HU, but only restored in LV following HR for 14 days. These results indicate that simulated microgravity leads to cardiac remodeling, and the remodeling changes can

  15. Rod photoreceptors protect from cone degeneration-induced retinal remodeling and restore visual responses in zebrafish

    PubMed Central

    Saade, Carole J.; Alvarez-Delfin, Karen; Fadool, James M.

    2013-01-01

    Humans are largely dependent upon cone-mediated vision. However, death or dysfunction of rods, the predominant photoreceptor subtype, results in secondary loss of cones, remodeling of retinal circuitry and blindness. The changes in circuitry may contribute to the vision deficit and undermine attempts at restoring sight. We exploit zebrafish larvae as a genetic model to specifically characterize changes associated with photoreceptor degenerations in a cone-dominated retina. Photoreceptors form synapses with two types of second order neurons, bipolar cells and horizontal cells. Using cell-specific reporter gene expression and immunolabeling for postsynaptic glutamate receptors, significant remodeling is observed following cone degeneration in the pde6cw59 larval retina but not rod degeneration in the Xops:mCFPq13 line. In adults, rods and cones are present in approximately equal numbers, and in pde6cw59 mutants glutamate receptor expression and synaptic structures in the outer plexiform layer are preserved, and visual responses are gained in these once-blind fish. We propose that the abundance of rods in the adult protects the retina from cone degeneration-induced remodeling. We test this hypothesis by genetically manipulating the number of rods in larvae. We show that an increased number and uniform distribution of rods in lor/tbx2bp22bbtl or six7 morpholino-injected larvae protect from pde6cw59-induced secondary changes. The observations that remodeling is a common consequence of photoreceptor death across species, and that in zebrafish a small number of surviving photoreceptors afford protection from degeneration-induced changes provides a model for systematic analysis of factors that slow or even prevent the secondary deteriorations associated with neural degenerative disease. PMID:23365220

  16. Rod photoreceptors protect from cone degeneration-induced retinal remodeling and restore visual responses in zebrafish.

    PubMed

    Saade, Carole J; Alvarez-Delfin, Karen; Fadool, James M

    2013-01-30

    Humans are largely dependent upon cone-mediated vision. However, death or dysfunction of rods, the predominant photoreceptor subtype, results in secondary loss of cones, remodeling of retinal circuitry, and blindness. The changes in circuitry may contribute to the vision deficit and undermine attempts at restoring sight. We exploit zebrafish larvae as a genetic model to specifically characterize changes associated with photoreceptor degenerations in a cone-dominated retina. Photoreceptors form synapses with two types of second-order neurons, bipolar cells, and horizontal cells. Using cell-specific reporter gene expression and immunolabeling for postsynaptic glutamate receptors, significant remodeling is observed following cone degeneration in the pde6c(w59) larval retina but not rod degeneration in the Xops:mCFP(q13) line. In adults, rods and cones are present in approximately equal numbers, and in pde6c(w59) mutants glutamate receptor expression and synaptic structures in the outer plexiform layer are preserved, and visual responses are gained in these once blind fish. We propose that the abundance of rods in the adult protects the retina from cone degeneration-induced remodeling. We test this hypothesis by genetically manipulating the number of rods in larvae. We show that an increased number and uniform distribution of rods in lor/tbx2b(p25bbtl) or six7 morpholino-injected larvae protect from pde6c(w59)-induced secondary changes. The observations that remodeling is a common consequence of photoreceptor death across species, and that in zebrafish a small number of surviving photoreceptors afford protection from degeneration-induced changes, provides a model for systematic analysis of factors that slow or even prevent the secondary deteriorations associated with neural degenerative disease.

  17. Spleen and Lymphatic System

    MedlinePlus

    ... A Week of Healthy Breakfasts Shyness Spleen and Lymphatic System KidsHealth > For Teens > Spleen and Lymphatic System A A A What's in this article? Why ... español El bazo y el sistema linfático The lymphatic system is an extensive drainage network that helps keep ...

  18. Rapid Lymphatic Dissemination of Encapsulated Group A Streptococci via Lymphatic Vessel Endothelial Receptor-1 Interaction.

    PubMed

    Lynskey, Nicola N; Banerji, Suneale; Johnson, Louise A; Holder, Kayla A; Reglinski, Mark; Wing, Peter A C; Rigby, David; Jackson, David G; Sriskandan, Shiranee

    2015-09-01

    The host lymphatic network represents an important conduit for pathogen dissemination. Indeed, the lethal human pathogen group A streptococcus has a predilection to induce pathology in the lymphatic system and draining lymph nodes, however the underlying basis and subsequent consequences for disease outcome are currently unknown. Here we report that the hyaluronan capsule of group A streptococci is a crucial virulence determinant for lymphatic tropism in vivo, and further, we identify the lymphatic vessel endothelial receptor-1 as the critical host receptor for capsular hyaluronan in the lymphatic system. Interference with this interaction in vivo impeded bacterial dissemination to local draining lymph nodes and, in the case of a hyper-encapsulated M18 strain, redirected streptococcal entry into the blood circulation, suggesting a pivotal role in the manifestation of streptococcal infections. Our results reveal a novel function for bacterial capsular polysaccharide in directing lymphatic tropism, with potential implications for disease pathology.

  19. Rapid Lymphatic Dissemination of Encapsulated Group A Streptococci via Lymphatic Vessel Endothelial Receptor-1 Interaction

    PubMed Central

    Johnson, Louise A.; Holder, Kayla A.; Reglinski, Mark; Wing, Peter A. C.; Rigby, David; Jackson, David G.; Sriskandan, Shiranee

    2015-01-01

    The host lymphatic network represents an important conduit for pathogen dissemination. Indeed, the lethal human pathogen group A streptococcus has a predilection to induce pathology in the lymphatic system and draining lymph nodes, however the underlying basis and subsequent consequences for disease outcome are currently unknown. Here we report that the hyaluronan capsule of group A streptococci is a crucial virulence determinant for lymphatic tropism in vivo, and further, we identify the lymphatic vessel endothelial receptor-1 as the critical host receptor for capsular hyaluronan in the lymphatic system. Interference with this interaction in vivo impeded bacterial dissemination to local draining lymph nodes and, in the case of a hyper-encapsulated M18 strain, redirected streptococcal entry into the blood circulation, suggesting a pivotal role in the manifestation of streptococcal infections. Our results reveal a novel function for bacterial capsular polysaccharide in directing lymphatic tropism, with potential implications for disease pathology. PMID:26352587

  20. Genetic remodeling of protein glycosylation in vivo induces autoimmune disease

    PubMed Central

    Chui, Daniel; Sellakumar, Gayathri; Green, Ryan S.; Sutton-Smith, Mark; McQuistan, Tammie; Marek, Kurt W.; Morris, Howard R.; Dell, Anne; Marth, Jamey D.

    2001-01-01

    Autoimmune diseases are among the most prevalent of afflictions, yet the genetic factors responsible are largely undefined. Protein glycosylation in the Golgi apparatus produces structural variation at the cell surface and contributes to immune self-recognition. Altered protein glycosylation and antibodies that recognize endogenous glycans have been associated with various autoimmune syndromes, with the possibility that such abnormalities may reflect genetic defects in glycan formation. We show that mutation of a single gene, encoding α-mannosidase II, which regulates the hybrid to complex branching pattern of extracellular asparagine (N)-linked oligosaccharide chains (N-glycans), results in a systemic autoimmune disease similar to human systemic lupus erythematosus. α-Mannosidase II-deficient autoimmune disease is due to an incomplete overlap of two conjoined pathways in complex-type N-glycan production. Lymphocyte development, abundance, and activation parameters are normal; however, serum immunoglobulins are increased and kidney function progressively falters as a disorder consistent with lupus nephritis develops. Autoantibody reactivity and circulating immune complexes are induced, and anti-nuclear antibodies exhibit reactivity toward histone, Sm antigen, and DNA. These findings reveal a genetic cause of autoimmune disease provoked by a defect in the pathway of protein N-glycosylation. PMID:11158608

  1. Atrial electrophysiological and molecular remodelling induced by obstructive sleep apnoea.

    PubMed

    Channaveerappa, Devika; Lux, Jacob C; Wormwood, Kelly L; Heintz, Timothy A; McLerie, Meredith; Treat, Jacqueline A; King, Hannah; Alnasser, Donia; Goodrow, Robert J; Ballard, Glenn; Decker, Robert; Darie, Costel C; Panama, Brian K

    2017-09-01

    Obstructive sleep apnoea (OSA) affects 9-24% of the adult population. OSA is associated with atrial disease, including atrial enlargement, fibrosis and arrhythmias. Despite the link between OSA and cardiac disease, the molecular changes in the heart which occur with OSA remain elusive. To study OSA-induced cardiac changes, we utilized a recently developed rat model which closely recapitulates the characteristics of OSA. Male Sprague Dawley rats, aged 50-70 days, received surgically implanted tracheal balloons which were inflated to cause transient airway obstructions. Rats were given 60 apnoeas per hour of either 13 sec. (moderate apnoea) or 23 sec. (severe apnoea), 8 hrs per day for 2 weeks. Controls received implants, but no inflations were made. Pulse oximetry measurements were taken at regular intervals, and post-apnoea ECGs were recorded. Rats had longer P wave durations and increased T wave amplitudes following chronic OSA. Proteomic analysis of the atrial tissue homogenates revealed that three of the nine enzymes in glycolysis, and two proteins related to oxidative phosphorylation, were down regulated in the severe apnoea group. Several sarcomeric and pro-hypertrophic proteins were also up regulated with OSA. Chronic OSA causes proteins changes in the atria which suggest impairment of energy metabolism and enhancement of hypertrophy. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  2. Somatic embryogenesis - Stress-induced remodeling of plant cell fate.

    PubMed

    Fehér, Attila

    2015-04-01

    Plants as sessile organisms have remarkable developmental plasticity ensuring heir continuous adaptation to the environment. An extreme example is somatic embryogenesis, the initiation of autonomous embryo development in somatic cells in response to exogenous and/or endogenous signals. In this review I briefly overview the various pathways that can lead to embryo development in plants in addition to the fertilization of the egg cell and highlight the importance of the interaction of stress- and hormone-regulated pathways during the induction of somatic embryogenesis. Somatic embryogenesis can be initiated in planta or in vitro, directly or indirectly, and the requirement for dedifferentiation as well as the way to achieve developmental totipotency in the various systems is discussed in light of our present knowledge. The initiation of all forms of the stress/hormone-induced in vitro as well as the genetically provoked in planta somatic embryogenesis requires extensive and coordinated genetic reprogramming that has to take place at the chromatin level, as the embryogenic program is under strong epigenetic repression in vegetative plant cells. Our present knowledge on chromatin-based mechanisms potentially involved in the somatic-to-embryogenic developmental transition is summarized emphasizing the potential role of the chromatin to integrate stress, hormonal, and developmental pathways leading to the activation of the embryogenic program. The role of stress-related chromatin reorganization in the genetic instability of in vitro cultures is also discussed. This article is part of a Special Issue entitled: Stress as a fundamental theme in cell plasticity.

  3. Tie1 is required for lymphatic valve and collecting vessel development

    PubMed Central

    Qu, Xianghu; Zhou, Bin; Baldwin, H. Scott

    2015-01-01

    Tie1 is a receptor tyrosine kinase with broad expression in embryonic endothelium. Reduction of Tie1 levels in mouse embryos with a hypomorphic Tie1 allele resulted in abnormal lymphatic patterning and architecture, decreased lymphatic draining efficiency, and ultimately, embryonic demise. Here we report that Tie1 is present uniformly throughout the lymphatics and from late embryonic/early postnatal stages, becomes more restricted to lymphatic valve regions. To investigate later events of lymphatic development, we employed Cre-loxP recombination utilizing a floxed Tie1 allele and an Nfatc1Cre line, to provide loxP excision predominantly in lymphatic endothelium and developing valves. Interestingly, unlike the early prenatal defects previously described by ubiquitous endothelial deletion, excision of Tie1 with Nfatc1Cre resulted in abnormal lymphatic defects in postnatal mice and was characterized by agenesis of lymphatic valves and a deficiency of collecting lymphatic vessels. Attenuation of Tie1 signaling in lymphatic endothelium prevented initiation of lymphatic valve specification by Prox1 high expression lymphatic endothelial cells that is associated with the onset of turbulent flow in the lymphatic circulation. Our findings reveal a fundamental role for Tie signaling during lymphatic vessel remodeling and valve morphogenesis and implicate it as a candidate gene involved in primary lymphedema. PMID:25576926

  4. Reconstitution of myocardial lymphatic vessels after acute infarction of rat heart.

    PubMed

    Sun, Q N; Wang, Y F; Guo, Z K

    2012-06-01

    We investigated the regeneration of cardiac lymphatic vessels and capillaries in the infarcted myocardiac zones after acute myocardial infarction in rats. The anterior descending artery of the heart was ligated for infarction and both immunohistochemistry and immunofluorescence were used to detect pathological changes of lymphatic vessels in infarcted zone (IZ), infarcted margin zone (MZ) and remote margin zone (RMZ) on days 7, 14, 21, and 28 after surgery. Dynamic variation of lymphatic vessels existed in IZ, MZ and RMZ at different stages after surgery. At day 7, lymphatic vessels and capillaries were not seen in the IZ, very thin lymphatic capillaries were obviously increased in the inner layer of the margin zone, and enlarged and increased lymphatic capillaries were found in the outer layer of margin zone. At 14 days, a few sparsely arranged lymphatic capillaries were observed in the IZ without marked changes in the MZ. At 21 days, constricted regenerating lymphatic capillaries in MZ were decreased, and lymphatic vessels exhibited sprouting towards the IZ. At 28 days, more lymphatic capillaries emerged in the IZ, and the morphology and number of lymphatic vessels and capillaries had returned to normal. There were no marked changes of lymphatic vessels and capillaries in RMZ compared to control myocardium at the 4 time points. This study demonstrates varied remodeling of lymphatic vessels and capillaries in the IZ and MZ after acute myocardial infarction, and these changes in lymphatic vessels likely play an important role for recovery of infarcted myocardiac function.

  5. Progression of carcinogen-induced fibrosarcomas is associated with the accumulation of naïve CD4+ T cells via blood vessels and lymphatics.

    PubMed

    Ondondo, Beatrice; Jones, Emma; Hindley, James; Cutting, Scott; Smart, Kathryn; Bridgeman, Hayley; Matthews, Katherine K; Ladell, Kristin; Price, David A; Jackson, David G; Godkin, Andrew; Ager, Ann; Gallimore, Awen

    2014-05-01

    The tumor microenvironment comprises newly formed blood and lymphatic vessels which shape the influx, retention and departure of lymphocytes within the tumor mass. Thus, by influencing the intratumoral composition of lymphocytes, these vessels affect the manner in which the adaptive immune system responds to the tumor, either promoting or impairing effective antitumor immunity. In our study, we utilized a mouse model of carcinogen-induced fibrosarcoma to examine the composition of tumor-infiltrating lymphocytes during tumor progression. In particular, we sought to determine whether CD4(+) Foxp3(+) regulatory T cells (Tregs) became enriched during tumor progression thereby contributing to tumor-driven immunosuppression. This was not the case as the proportion of Tregs and effector CD4(+) T cells actually declined within the tumor owing to the unexpected accumulation of naïve T cells. However, we found no evidence for antigen-driven migration of these T cells or for their participation in an antitumor immune response. Our data support the notion that lymphocytes can enter tumors via aberrantly formed blood and lymphatic vessels. Such findings suggest that targeting both the tumor vasculature and lymphatics will alter the balance of lymphocyte subpopulations that enter the tumor mass. A consideration of this aspect of tumor immunology may be critical to the success of solid cancer immunotherapies.

  6. Brain Remodelling following Endothelin-1 Induced Stroke in Conscious Rats

    PubMed Central

    Abeysinghe, Hima C. S.; Bokhari, Laita; Dusting, Gregory J.; Roulston, Carli L.

    2014-01-01

    The extent of stroke damage in patients affects the range of subsequent pathophysiological responses that influence recovery. Here we investigate the effect of lesion size on development of new blood vessels as well as inflammation and scar formation and cellular responses within the subventricular zone (SVZ) following transient focal ischemia in rats (n = 34). Endothelin-1-induced stroke resulted in neurological deficits detected between 1 and 7 days (P<0.001), but significant recovery was observed beyond this time. MCID image analysis revealed varying degrees of damage in the ipsilateral cortex and striatum with infarct volumes ranging from 0.76–77 mm3 after 14 days, where larger infarct volumes correlated with greater functional deficits up to 7 days (r = 0.53, P<0.05). Point counting of blood vessels within consistent sample regions revealed that increased vessel numbers correlated significantly with larger infarct volumes 14 days post-stroke in the core cortical infarct (r = 0.81, P<0.0001), core striatal infarct (r = 0.91, P<0.005) and surrounding border zones (r = 0.66, P<0.005; and r = 0.73, P<0.05). Cell proliferation within the SVZ also increased with infarct size (P<0.01) with a greater number of Nestin/GFAP positive cells observed extending towards the border zone in rats with larger infarcts. Lesion size correlated with both increased microglia and astrocyte activation, with severely diffuse astrocyte transition, the formation of the glial scar being more pronounced in rats with larger infarcts. Thus stroke severity affects cell proliferation within the SVZ in response to injury, which may ultimately make a further contribution to glial scar formation, an important factor to consider when developing treatment strategies that promote neurogenesis. PMID:24809543

  7. Brain remodelling following endothelin-1 induced stroke in conscious rats.

    PubMed

    Abeysinghe, Hima C S; Bokhari, Laita; Dusting, Gregory J; Roulston, Carli L

    2014-01-01

    The extent of stroke damage in patients affects the range of subsequent pathophysiological responses that influence recovery. Here we investigate the effect of lesion size on development of new blood vessels as well as inflammation and scar formation and cellular responses within the subventricular zone (SVZ) following transient focal ischemia in rats (n = 34). Endothelin-1-induced stroke resulted in neurological deficits detected between 1 and 7 days (P<0.001), but significant recovery was observed beyond this time. MCID image analysis revealed varying degrees of damage in the ipsilateral cortex and striatum with infarct volumes ranging from 0.76-77 mm3 after 14 days, where larger infarct volumes correlated with greater functional deficits up to 7 days (r = 0.53, P<0.05). Point counting of blood vessels within consistent sample regions revealed that increased vessel numbers correlated significantly with larger infarct volumes 14 days post-stroke in the core cortical infarct (r = 0.81, P<0.0001), core striatal infarct (r = 0.91, P<0.005) and surrounding border zones (r = 0.66, P<0.005; and r = 0.73, P<0.05). Cell proliferation within the SVZ also increased with infarct size (P<0.01) with a greater number of Nestin/GFAP positive cells observed extending towards the border zone in rats with larger infarcts. Lesion size correlated with both increased microglia and astrocyte activation, with severely diffuse astrocyte transition, the formation of the glial scar being more pronounced in rats with larger infarcts. Thus stroke severity affects cell proliferation within the SVZ in response to injury, which may ultimately make a further contribution to glial scar formation, an important factor to consider when developing treatment strategies that promote neurogenesis.

  8. Statin reverses smoke-induced pulmonary hypertension and prevents emphysema but not airway remodeling.

    PubMed

    Wright, Joanne L; Zhou, Steven; Preobrazhenska, Olena; Marshall, Caroline; Sin, Don D; Laher, Ismail; Golbidi, Saeid; Churg, Andrew M

    2011-01-01

    the potential role of statins in treating chronic obstructive pulmonary disease (COPD) is controversial, and it is unclear what anatomic COPD lesions statins affect. to determine whether an intervention of simvastatin could alter cigarette smoke-induced pulmonary hypertension. we exposed guinea pigs to cigarette smoke for 6 months. In half the animals, simvastatin therapy was initiated after 3 months of smoke exposure. Pulmonary arterial systolic pressures were monitored weekly with a radiotelemetric catheter; additional physiologic and morphologic measurements were made at sacrifice after 6 months. Precision-cut lung explants were assessed for evidence of endothelial dysfunction, and in situ vascular nitric oxide generation was measured with 4,5-diaminofluorescein diacetate. cigarette smoke increased the pulmonary arterial systolic pressure after approximately 4 weeks. Simvastatin returned the pressure to control levels within 4 weeks of starting treatment, and ameliorated smoke-induced small arterial remodeling as well as emphysema measured both physiologically and morphometrically at 6 months, but did not prevent smoke-induced small airway remodeling either physiologically or morphologically. In precision-cut lung slices simvastatin reversed small arterial endothelial dysfunction, and partially reversed smoke-induced loss of vascular nitric oxide generation. simvastatin, as an intervention therapy, reverses the pulmonary vascular effects of cigarette smoke, including pulmonary hypertension, and prevents smoke-induced emphysema, but does not prevent small airway remodeling. This is the first demonstration that an intervention can reverse a COPD-associated cigarette smoke-induced anatomic abnormality. The study also shows the importance of examining all three anatomic lung compartments when assessing the effects of a potential drug intervention in patients with COPD.

  9. Endothelin-1 mediates intermittent hypoxia-induced inflammatory vascular remodeling through HIF-1 activation.

    PubMed

    Gras, Emmanuelle; Belaidi, Elise; Briançon-Marjollet, Anne; Pépin, Jean-Louis; Arnaud, Claire; Godin-Ribuot, Diane

    2016-02-15

    Obstructive sleep apnea (OSA) is a major risk factor for cardiovascular mortality, and apnea-induced intermittent hypoxia (IH) is known to promote various cardiovascular alterations such as vascular remodeling. However, the mechanisms that underlie IH remain incompletely investigated. We previously demonstrated that the hypoxia-inducible factor-1 (HIF-1) and endothelin-1 (ET-1) are involved in arterial hypertension and myocardial susceptibility to infarction induced by IH. Thus the objective of the present study was to investigate whether both ET-1 and HIF-1 were also involved in the vascular inflammatory remodeling induced by IH. Mice partially deficient for the Hif1α gene (HIF-1α(+/-)) and their wild-type equivalents, as well as C57BL/6J mice, treated or not with bosentan, a dual endothelin receptor antagonist, were exposed to IH or normoxia for 2 wk, 8 h/day. Splenocyte proliferative and secretory capacities, aortic nuclear factor-κB (NF-κB) and HIF-1 activities, and expression of cytokines and intima-media thickness (IMT) were measured. IH induced a systemic and aortic inflammation characterized by an increase in splenocyte proliferative and secretory capacities, aortic NF-κB activity, and cytokine expression in the aortic wall. This was accompanied by an increase in IMT. These modifications were prevented in HIF-1α(+/-) and bosentan-treated mice. The results of this study suggest that ET-1 is a major contributor to the vascular inflammatory remodeling induced by OSA-related IH, probably through HIF-1-dependent activation of NF-κB.

  10. Antagonism of Stem Cell Factor/c-kit Signaling Attenuates Neonatal Chronic Hypoxia-Induced Pulmonary Vascular Remodeling

    PubMed Central

    Young, Karen C; Torres, Eneida; Hehre, Dorothy; Wu, Shu; Suguihara, Cleide; Hare, Joshua M.

    2015-01-01

    Background Accumulating evidence suggests that c-kit positive cells are present in the remodeled pulmonary vasculature bed of patients with pulmonary hypertension (PH). Whether stem cell factor (SCF)/ c-kit regulated pathways potentiate pulmonary vascular remodeling is unknown. Here, we tested the hypothesis that attenuated c-kit signaling would decrease chronic hypoxia-induced pulmonary vascular remodeling by decreasing pulmonary vascular cell mitogenesis. Methods Neonatal FVB/NJ mice treated with non-immune IgG (PL), or c-kit neutralizing antibody (ACK2) as well as c-kit mutant mice (WBB6F1- Kit W− v/ +) and their congenic controls, were exposed to normoxia (FiO2=0.21) or hypoxia (FiO2=0.12) for two weeks. Following this exposure, right ventricular systolic pressure (RVSP), right ventricular hypertrophy (RVH), pulmonary vascular cell proliferation and remodeling were evaluated. Results As compared to chronically hypoxic controls, c-kit mutant mice had decreased RVSP, RVH, pulmonary vascular remodeling and proliferation. Consistent with these findings, administration of ACK2 to neonatal mice with chronic hypoxia-induced PH decreased RVSP, RVH, pulmonary vascular cell proliferation and remodeling. This attenuation in PH was accompanied by decreased extracellular signal-regulated protein kinase (ERK) 1/2 activation. Conclusion SCF/c-kit signaling may potentiate chronic hypoxia-induced vascular remodeling by modulating ERK activation. Inhibition of c-kit activity may be a potential strategy to alleviate PH. PMID:26705118

  11. Lymphangiogenesis in myocardial remodelling after infarction

    PubMed Central

    Ishikawa, Y; Akishima-Fukasawa, Y; Ito, K; Akasaka, Y; Tanaka, M; Shimokawa, R; Kimura-Matsumoto, M; Morita, H; Sato, S; Kamata, I; Ishii, T

    2007-01-01

    Ishikawa Y, Akishima-Fukasawa Y, Ito K, Akasaka Y, Tanaka M, Shimokawa R, Kimura-Matsumoto M, Morita H, Sato S, Kamata I & Ishii T (2007) Histopathology51, 345–353 Lymphangiogenesis in myocardial remodelling after infarction Aims The lymphatic system is involved in fluid homeostasis of the cardiac interstitium, but lymphangiogenesis in myocardial remodelling has not previously been examined histopathologically. The aim was to investigate by D2-40 immunohistochemistry the sequential changes in lymphatic distribution in the process of myocardial remodelling after myocardial infarction (MI). Methods and results Myocardial tissues in various phases of healing after MI were obtained from 40 autopsied hearts. D2-40+ lymphatic vessel density (LD) and CD34+ blood vessel density (BD) in the lesion were determined. BD decreased with advance of myocardial necrosis, subsequently increased at the early stage of granulation and thereafter decreased with the progression of scar formation. In contrast, lymphatic vessels were not detected in lesions with coagulation necrosis, and newly formed lymphatics first appeared in the early stages of granulation. A subsequent increase in LD was demonstrated in the late stages of granulation, and lymphatics remained up to the scar phase. Vascular endothelial growth factor-C was consistently expressed in viable cardiomyocytes around the lesion in all of these stages. Conclusion In myocardial remodelling after MI, lymphangiogenesis lags behind blood vessel angiogenesis; newly formed lymphatics may be involved mainly in the maturation of fibrosis and scar formation through the drainage of excessive proteins and fluid. PMID:17727476

  12. Immunopathogenesis of lymphatic filarial disease.

    PubMed

    Babu, Subash; Nutman, Thomas B

    2012-11-01

    Although two thirds of the 120 million people infected with lymph-dwelling filarial parasites have subclinical infections, ~40 million have lymphedema and/or other pathologic manifestations including hydroceles (and other forms of urogenital disease), episodic adenolymphangitis, tropical pulmonary eosinophilia, lymphedema, and (in its most severe form) elephantiasis. Adult filarial worms reside in the lymphatics and lymph nodes and induce changes that result in dilatation of lymphatics and thickening of the lymphatic vessel walls. Progressive lymphatic damage and pathology results from the summation of the effect of tissue alterations induced by both living and nonliving adult parasites, the host inflammatory response to the parasites and their secreted antigens, the host inflammatory response to the endosymbiont Wolbachia, and those seen as a consequence of secondary bacterial or fungal infections. Inflammatory damage induced by filarial parasites appears to be multifactorial, with endogenous parasite products, Wolbachia, and host immunity all playing important roles. This review will initially examine the prototypical immune responses engendered by the parasite and delineate the regulatory mechanisms elicited to prevent immune-mediated pathology. This will be followed by a discussion of the proposed mechanisms underlying pathogenesis, with the central theme being that pathogenesis is a two-step process-the first initiated by the parasite and host innate immune system and the second propagated mainly by the host's adaptive immune system and by other factors (including secondary infections).

  13. Electrophysiologic remodeling of the left ventricle in pressure overload-induced right ventricular failure.

    PubMed

    Hardziyenka, Maxim; Campian, Maria E; Verkerk, Arie O; Surie, Sulaiman; van Ginneken, Antoni C G; Hakim, Sara; Linnenbank, André C; de Bruin-Bon, H A C M Rianne; Beekman, Leander; van der Plas, Mart N; Remme, Carol A; van Veen, Toon A B; Bresser, Paul; de Bakker, Jacques M T; Tan, Hanno L

    2012-06-12

    The purpose of this study was to analyze the electrophysiologic remodeling of the atrophic left ventricle (LV) in right ventricular (RV) failure (RVF) after RV pressure overload. The LV in pressure-induced RVF develops dysfunction, reduction in mass, and altered gene expression, due to atrophic remodeling. LV atrophy is associated with electrophysiologic remodeling. We conducted epicardial mapping in Langendorff-perfused hearts, patch-clamp studies, gene expression studies, and protein level studies of the LV in rats with pressure-induced RVF (monocrotaline [MCT] injection, n = 25; controls with saline injection, n = 18). We also performed epicardial mapping of the LV in patients with RVF after chronic thromboembolic pulmonary hypertension (CTEPH) (RVF, n = 10; no RVF, n = 16). The LV of rats with MCT-induced RVF exhibited electrophysiologic remodeling: longer action potentials (APs) at 90% repolarization and effective refractory periods (ERPs) (60 ± 1 ms vs. 44 ± 1 ms; p < 0.001), and slower longitudinal conduction velocity (62 ± 2 cm/s vs. 70 ± 1 cm/s; p = 0.003). AP/ERP prolongation agreed with reduced Kcnip2 expression, which encodes the repolarizing potassium channel subunit KChIP2 (0.07 ± 0.01 vs. 0.11 ± 0.02; p < 0.05). Conduction slowing was not explained by impaired impulse formation, as AP maximum upstroke velocity, whole-cell sodium current magnitude/properties, and mRNA levels of Scn5a were unaltered. Instead, impulse transmission in RVF was hampered by reduction in cell length (111.6 ± 0.7 μm vs. 122.0 ± 0.4 μm; p = 0.02) and width (21.9 ± 0.2 μm vs. 25.3 ± 0.3 μm; p = 0.002), and impaired cell-to-cell impulse transmission (24% reduction in Connexin-43 levels). The LV of patients with CTEPH with RVF also exhibited ERP prolongation (306 ± 8 ms vs. 268 ± 5 ms; p = 0.001) and conduction slowing (53 ± 3 cm/s vs. 64 ± 3 cm/s; p = 0.005). Pressure-induced RVF is associated with electrophysiologic remodeling of the atrophic LV. Copyright

  14. Emerging Roles of Lymphatic Vasculature in Immunity

    PubMed Central

    2017-01-01

    The lymphatic vasculature has been regarded as a passive conduit for interstitial fluid and responsible for the absorption of macromolecules such as proteins or lipids and transport of nutrients from food. However, emerging data show that the lymphatic vasculature system plays an important role in immune modulation. One of its major roles is to coordinate antigen transport and immune-cell trafficking from peripheral tissues to secondary lymphoid organs, lymph nodes. This perspective was recently updated with the notion that the interaction between lymphatic endothelial cells and leukocytes controls the immune-cell migration and immune responses by regulating lymphatic flow and various secreted molecules such as chemokines and cytokines. In this review, we introduce the lymphatic vasculature networks and genetic transgenic models for research on the lymphatic vasculature system. Next, we discuss the contribution of lymphatic endothelial cells to the control of immune-cell trafficking and to maintenance of peripheral tolerance. Finally, the physiological roles and features of the lymphatic vasculature system are further discussed regarding inflammation-induced lymphangiogenesis in a pathological condition, especially in mucosal tissues such as the gastrointestinal tract and respiratory tract. PMID:28261022

  15. Role of chymase in cigarette smoke-induced pulmonary artery remodeling and pulmonary hypertension in hamsters.

    PubMed

    Wang, Tao; Han, Su-Xia; Zhang, Shang-Fu; Ning, Yun-Ye; Chen, Lei; Chen, Ya-Juan; He, Guang-Ming; Xu, Dan; An, Jin; Yang, Ting; Zhang, Xiao-Hong; Wen, Fu-Qiang

    2010-03-31

    Cigarette smoking is an important risk factor for pulmonary arterial hypertension (PAH) in chronic obstructive pulmonary disease (COPD). Chymase has been shown to function in the enzymatic production of angiotensin II (AngII) and the activation of transforming growth factor (TGF)-beta1 in the cardiovascular system. The aim of this study was to determine the potential role of chymase in cigarette smoke-induced pulmonary artery remodeling and PAH. Hamsters were exposed to cigarette smoke; after 4 months, lung morphology and tissue biochemical changes were examined using immunohistochemistry, Western blotting, radioimmunoassay and reverse-transcription polymerase chain reaction. Our results show that chronic cigarette smoke exposure significantly induced elevation of right ventricular systolic pressures (RVSP) and medial hypertrophy of pulmonary arterioles in hamsters, concurrent with an increase of chymase activity and synthesis in the lung. Elevated Ang II levels and enhanced TGF-beta1/Smad signaling activation were also observed in smoke-exposed lungs. Chymase inhibition with chymostatin reduced the cigarette smoke-induced increase in chymase activity and Ang II concentration in the lung, and attenuated the RVSP elevation and the remodeling of pulmonary arterioles. Chymostatin did not affect angiotensin converting enzyme (ACE) activity in hamster lungs. These results suggest that chronic cigarette smoke exposure can increase chymase activity and expression in hamster lungs. The capability of activated chymase to induce Ang II formation and TGF-beta1 signaling may be part of the mechanism for smoking-induced pulmonary vascular remodeling. Thus, our study implies that blockade of chymase might provide benefits to PAH smokers.

  16. Lysyl oxidase overexpression accelerates cardiac remodeling and aggravates angiotensin II-induced hypertrophy.

    PubMed

    Galán, María; Varona, Saray; Guadall, Anna; Orriols, Mar; Navas, Miquel; Aguiló, Silvia; de Diego, Alicia; Navarro, María A; García-Dorado, David; Rodríguez-Sinovas, Antonio; Martínez-González, José; Rodriguez, Cristina

    2017-09-01

    Lysyl oxidase (LOX) controls matrix remodeling, a key process that underlies cardiovascular diseases and heart failure; however, a lack of suitable animal models has limited our knowledge with regard to the contribution of LOX to cardiac dysfunction. Here, we assessed the impact of LOX overexpression on ventricular function and cardiac hypertrophy in a transgenic LOX (TgLOX) mouse model with a strong cardiac expression of human LOX. TgLOX mice exhibited high expression of the transgene in cardiomyocytes and cardiofibroblasts, which are associated with enhanced LOX activity and H2O2 production and with cardiofibroblast reprogramming. LOX overexpression promoted an age-associated concentric remodeling of the left ventricle and impaired diastolic function. Furthermore, LOX transgenesis aggravated angiotensin II (Ang II)-induced cardiac hypertrophy and dysfunction, which triggered a greater fibrotic response that was characterized by stronger collagen deposition and cross-linking and high expression of fibrotic markers. In addition, LOX transgenesis increased the Ang II-induced myocardial inflammatory infiltrate, exacerbated expression of proinflammatory markers, and decreased that of cardioprotective factors. Mechanistically, LOX overexpression enhanced oxidative stress and potentiated the Ang II-mediated cardiac activation of p38 MAPK while reducing AMPK activation. Our findings suggest that LOX induces an age-dependent disturbance of diastolic function and aggravates Ang II-induced hypertrophy, which provides novel insights into the role of LOX in cardiac performance.-Galán, M., Varona, S., Guadall, A., Orriols, M., Navas, M., Aguiló, S., de Diego, A., Navarro, M. A., García-Dorado, D., Rodríguez-Sinovas, A., Martínez-González, J., Rodriguez, C. Lysyl oxidase overexpression accelerates cardiac remodeling and aggravates angiotensin II-induced hypertrophy. © FASEB.

  17. Pro-arrhythmogenic effects of atrial fibrillation-induced electrical remodelling: insights from the three-dimensional virtual human atria.

    PubMed

    Colman, Michael A; Aslanidi, Oleg V; Kharche, Sanjay; Boyett, Mark R; Garratt, Clifford; Hancox, Jules C; Zhang, Henggui

    2013-09-01

    Chronic atrial fibrillation (AF) is associated with structural and electrical remodelling in the atria, which are associated with a high recurrence of AF. Through biophysically detailed computer modelling, this study investigated mechanisms by which AF-induced electrical remodelling promotes and perpetuates AF. A family of Courtemanche-Ramirez-Nattel variant models of human atrial cell action potentials (APs), taking into account of intrinsic atrial electrophysiological properties, was modified to incorporate various experimental data sets on AF-induced changes of major ionic channel currents (ICaL, IKur, Ito, IK1, IKs, INaCa) and on intracellular Ca(2+) handling. The single cell models for control and AF-remodelled conditions were incorporated into multicellular three-dimensional (3D) atrial tissue models. Effects of the AF-induced electrical remodelling were quantified as the changes of AP profile, AP duration (APD) and its dispersion across the atria, and the vulnerability of atrial tissue to the initiation of re-entry. The dynamic behaviour of re-entrant excitation waves in the 3D models was characterised. In our simulations, AF-induced electrical remodelling abbreviated atrial APD non-uniformly across the atria; this resulted in relatively short APDs co-existing with marked regional differences in the APD at junctions of the crista terminalis/pectinate muscle, pulmonary veins/left atrium. As a result, the measured tissue vulnerability to re-entry initiation at these tissue junctions was increased. The AF-induced electrical remodelling also stabilized and accelerated re-entrant excitation waves, leading to rapid and sustained re-entry. Under the AF-remodelled condition, re-entrant scroll waves in the 3D model degenerated into persistent and erratic wavelets, leading to fibrillation. In conclusion, realistic 3D atrial tissue models indicate that AF-induced electrical remodelling produces regionally heterogeneous and shortened APD; these respectively facilitate

  18. Functional brown adipose tissue limits cardiomyocyte injury and adverse remodeling in catecholamine-induced cardiomyopathy

    PubMed Central

    Thoonen, Robrecht; Ernande, Laura; Cheng, Juan; Nagasaka, Yasuko; Yao, Vincent; Miranda-Bezerra, Alexandre; Chen, Chan; Chao, Wei; Panagia, Marcello; Sosnovik, David E.; Puppala, Dheeraj; Armoundas, Antonis A.; Hindle, Allyson; Bloch, Kenneth D.; Buys, Emmanuel S.; Scherrer-Crosbie, Marielle

    2015-01-01

    Brown adipose tissue (BAT) has well recognized thermogenic properties mediated by uncoupling protein 1 (UCP1); more recently, BAT has been demonstrated to modulate cardiovascular risk factors. To investigate whether BAT also affects myocardial injury and remodeling, UCP1-deficient (UCP1−/−) mice, which have dysfunctional BAT, were subjected to catecholamine-induced cardiomyopathy. At baseline, there were no differences in echocardiographic parameters, plasma cardiac troponin I (cTnI) or myocardial fibrosis between wild-type (WT) and UCP1−/− mice. Isoproterenol infusion increased cTnI and myocardial fibrosis and induced left ventricular (LV) hypertrophy in both WT and UCP1−/− mice. UCP1−/− mice also demonstrated exaggerated myocardial injury, fibrosis, and adverse remodeling, as well as decreased survival. Transplantation of WT BAT to UCP1−/− mice prevented the isoproterenol-induced cTnI increase and improved survival, whereas UCP1−/− BAT transplanted to either UCP1−/− or WT mice had no effect on cTnI release. After 3 days of isoproterenol treatment, phosphorylated AKT and ERK were lower in the LV's of UCP1−/− mice than in those of WT mice. Activation of BAT was also noted in a model of chronic ischemic cardiomyopathy, and was correlated to LV dysfunction. Deficiency in UCP1, and accompanying BAT dysfunction, increases cardiomyocyte injury and adverse LV remodeling, and decreases survival in a mouse model of catecholamine-induced cardiomyopathy. Myocardial injury and decreased survival are rescued by transplantation of functional BAT to UCP1−/− mice, suggesting a systemic cardioprotective role of functional BAT. BAT is also activated in chronic ischemic cardiomyopathy. PMID:25968336

  19. Inhalation of hydrogen gas attenuates left ventricular remodeling induced by intermittent hypoxia in mice.

    PubMed

    Hayashi, Tetsuya; Yoshioka, Toshitaka; Hasegawa, Kenichi; Miyamura, Masatoshi; Mori, Tatsuhiko; Ukimura, Akira; Matsumura, Yasuo; Ishizaka, Nobukazu

    2011-09-01

    Sleep apnea syndrome increases the risk of cardiovascular morbidity and mortality. We previously reported that intermittent hypoxia increases superoxide production in a manner dependent on nicotinamide adenine dinucleotide phosphate and accelerates adverse left ventricular (LV) remodeling. Recent studies have suggested that hydrogen (H(2)) may have an antioxidant effect by reducing hydroxyl radicals. In this study, we investigated the effects of H(2) gas inhalation on lipid metabolism and LV remodeling induced by intermittent hypoxia in mice. Male C57BL/6J mice (n = 62) were exposed to intermittent hypoxia (repetitive cycle of 1-min periods of 5 and 21% oxygen for 8 h during daytime) for 7 days. H(2) gas (1.3 vol/100 vol) was given either at the time of reoxygenation, during hypoxic conditions, or throughout the experimental period. Mice kept under normoxic conditions served as controls (n = 13). Intermittent hypoxia significantly increased plasma levels of low- and very low-density cholesterol and the amount of 4-hydroxy-2-nonenal-modified protein adducts in the LV myocardium. It also upregulated mRNA expression of tissue necrosis factor-α, interleukin-6, and brain natriuretic peptide, increased production of superoxide, and induced cardiomyocyte hypertrophy, nuclear deformity, mitochondrial degeneration, and interstitial fibrosis. H(2) gas inhalation significantly suppressed these changes induced by intermittent hypoxia. In particular, H(2) gas inhaled at the timing of reoxygenation or throughout the experiment was effective in preventing dyslipidemia and suppressing superoxide production in the LV myocardium. These results suggest that inhalation of H(2) gas was effective for reducing oxidative stress and preventing LV remodeling induced by intermittent hypoxia relevant to sleep apnea.

  20. Evidence for cardiac atrophic remodeling in cancer-induced cachexia in mice.

    PubMed

    Tian, Min; Asp, Michelle L; Nishijima, Yoshinori; Belury, Martha A

    2011-11-01

    Cachexia is a common complication in cancer patients, which dramatically reduces quality of life and survival. In contrast to the well-studied feature of skeletal muscle loss, alterations in cardiac muscle are unclear. Recently, we reported that heart contractile function was significantly impaired in mice with colon-26 (C26) tumors, a widely used rodent model of cancer cachexia. In the present study, we investigated the potential underlying mechanisms for decreased heart function, specifically related to cardiac remodeling and atrophy. In cachectic mice bearing C26 tumors compared to mice without tumors, there was a gene expression pattern for cardiac remodeling, including increased BNP and c-fos, decreased PPARα and its responsive gene CPT1β, and a switch from 'adult' isoforms (MHCα, GLUT4) to 'fetal' isoforms (MHCβ and GLUT1). Echocardiography identified a decreased cardiac wall thickness. RT-PCR and Western blotting revealed a decreased amount of cardiac myofibrillar proteins MHC and troponin I, induced expression of E-3 ligases (MuRF-1 and Atrogin-1) and increased protein ubiquitination, providing evidence for cardiac atrophy in mice with cancer cachexia. Regulatory signaling pathways mediating these changes may include p44/42 MAPK. Together, these data provide evidence that pathways leading to cardiac remodeling and atrophy occur in mice with C26 cachexia.

  1. Local alignment vectors reveal cancer cell-induced ECM fiber remodeling dynamics.

    PubMed

    Lee, Byoungkoo; Konen, Jessica; Wilkinson, Scott; Marcus, Adam I; Jiang, Yi

    2017-01-03

    Invasive cancer cells interact with the surrounding extracellular matrix (ECM), remodeling ECM fiber network structure by condensing, degrading, and aligning these fibers. We developed a novel local alignment vector analysis method to quantitatively measure collagen fiber alignment as a vector field using Circular Statistics. This method was applied to human non-small cell lung carcinoma (NSCLC) cell lines, embedded as spheroids in a collagen gel. Collagen remodeling was monitored using second harmonic generation imaging under normal conditions and when the LKB1-MARK1 pathway was disrupted through RNAi-based approaches. The results showed that inhibiting LKB1 or MARK1 in NSCLC increases the collagen fiber alignment and captures outward alignment vectors from the tumor spheroid, corresponding to high invasiveness of LKB1 mutant cancer cells. With time-lapse imaging of ECM micro-fiber morphology, the local alignment vector can measure the dynamic signature of invasive cancer cell activity and cell-migration-induced ECM and collagen remodeling and realigning dynamics.

  2. Local alignment vectors reveal cancer cell-induced ECM fiber remodeling dynamics

    PubMed Central

    Lee, Byoungkoo; Konen, Jessica; Wilkinson, Scott; Marcus, Adam I.; Jiang, Yi

    2017-01-01

    Invasive cancer cells interact with the surrounding extracellular matrix (ECM), remodeling ECM fiber network structure by condensing, degrading, and aligning these fibers. We developed a novel local alignment vector analysis method to quantitatively measure collagen fiber alignment as a vector field using Circular Statistics. This method was applied to human non-small cell lung carcinoma (NSCLC) cell lines, embedded as spheroids in a collagen gel. Collagen remodeling was monitored using second harmonic generation imaging under normal conditions and when the LKB1-MARK1 pathway was disrupted through RNAi-based approaches. The results showed that inhibiting LKB1 or MARK1 in NSCLC increases the collagen fiber alignment and captures outward alignment vectors from the tumor spheroid, corresponding to high invasiveness of LKB1 mutant cancer cells. With time-lapse imaging of ECM micro-fiber morphology, the local alignment vector can measure the dynamic signature of invasive cancer cell activity and cell-migration-induced ECM and collagen remodeling and realigning dynamics. PMID:28045069

  3. Aggravated myocardial infarction-induced cardiac remodeling and heart failure in histamine-deficient mice

    PubMed Central

    Chen, Jinmiao; Hong, Tao; Ding, Suling; Deng, Long; Abudupataer, Mieradilijiang; Zhang, Weiwei; Tong, Minghong; Jia, Jianguo; Gong, Hui; Zou, Yunzeng; Wang, Timothy C.; Ge, Junbo; Yang, Xiangdong

    2017-01-01

    Histamine has pleiotropic pathophysiological effects, but its role in myocardial infarction (MI)-induced cardiac remodeling remains unclear. Histidine decarboxylase (HDC) is the main enzyme involved in histamine production. Here, we clarified the roles of HDC-expressing cells and histamine in heart failure post-MI using HDC-EGFP transgenic mice and HDC-knockout (HDC−/−) mice. HDC+CD11b+ myeloid cell numbers markedly increased in the injured hearts, and histamine levels were up-regulated in the circulation post-MI. HDC−/− mice exhibited more adverse cardiac remodeling, poorer left ventricular function and higher mortality by increasing cardiac fibrogenesis post-MI. In vitro assays further confirmed that histamine inhibited heart fibroblast proliferation. Furthermore, histamine enhanced the signal transducer and activator of transcription (STAT)-6 phosphorylation level in murine heart fibroblasts, and the inhibitive effects of histamine on fibroblast proliferation could be blocked by JAK3/STAT6 signaling selective antagonist. STAT6-knockout (STAT6−/−) mice had a phenotype similar to that of HDC−/− mice post-MI; however, in contrast to HDC−/− mice, the beneficial effects of exogenous histamine injections were abrogated in STAT6−/− mice. These data suggest that histamine exerts protective effects by modulating cardiac fibrosis and remodeling post-MI, in part through the STAT6-dependent signaling pathway. PMID:28272448

  4. COX-2 inhibition and hypoxia-induced pulmonary hypertension: effects on pulmonary vascular remodeling and contractility

    PubMed Central

    Fredenburgh, Laura E.; Ma, Jun; Perrella, Mark A.

    2009-01-01

    Pulmonary arterial hypertension (PAH) is a significant disease process characterized by elevated pulmonary vascular resistance leading to increased right ventricular afterload and ultimately progressing to right ventricular dysfunction and often death. Irreversible remodeling of the pulmonary vasculature is the hallmark of pulmonary hypertension and frequently leads to progressive functional decline in patients with PAH despite treatment with currently available therapies. Metabolites of the arachidonic acid cascade play an important homeostatic role in the pulmonary vasculature and dysregulation of pathways downstream of arachidonic acid play a central role in the pathobiology of PAH. Cyclooxygenase-2 (COX-2) is upregulated in pulmonary artery smooth muscle cells (PASMC) and inflammatory cells during hypoxia and plays a protective role in the lung’s response to hypoxia. We recently demonstrated that absence of COX-2 was detrimental in a mouse model of hypoxia-induced pulmonary hypertension. Exposure of COX-2 null mice to hypoxia resulted in severe pulmonary hypertension characterized by enhanced pulmonary vascular remodeling and significant upregulation of the ET-1 receptor (ETAR) in the lung following hypoxia. Absence of COX-2 in vitro led to enhanced contractility of PASMC following exposure to hypoxia that could be attenuated by iloprost, a prostaglandin I2 analog. These findings suggest that selective inhibition of COX-2 may have detrimental pulmonary vascular consequences in patients with pre-existing pulmonary hypertension or underlying hypoxemic lung diseases. Here we discuss our recent data demonstrating the adverse consequences of COX-2 inhibition on pulmonary vascular remodeling and PASMC contractility. PMID:19577709

  5. Exogenous midkine administration prevents cardiac remodeling in pacing-induced congestive heart failure of rabbits.

    PubMed

    Harada, Masahide; Hojo, Mayumi; Kamiya, Kaichiro; Kadomatsu, Kenji; Murohara, Toyoaki; Kodama, Itsuo; Horiba, Mitsuru

    2016-01-01

    Midkine (MK), a heparin-binding growth factor, has been shown to prevent cardiac remodeling after ischemic injury through its anti-apoptotic effect. Cell apoptosis is central to the pathophysiology of cardiac remodeling in congestive heart failure (CHF) of ischemic as well as non-ischemic origin. We hypothesized that MK exerts the anti-apoptotic cardioprotective effect in CHF of non-ischemic etiology. MK protein or vehicle (normal saline) was subcutaneously administered in tachycardia-induced CHF rabbits (right ventricular pacing, 350 beats/min, 4 weeks). The vehicle-treated rabbits (n = 19, control) demonstrated severe CHF and high mortality rate, whereas MK (n = 16) demonstrated a well-compensated state and a lower mortality rate. In echocardiography, left ventricular (LV) end-diastolic dimension decreased in MK versus control, whereas LV systolic function increased. In histological analysis (picrosirius red staining), MK decreased collagen deposition area compared with control. TUNEL staining showed that MK prevented cell apoptosis and minimized myocyte loss in the CHF rabbit ventricle, associated with activation of PI3-K/Akt signaling, producing a parallel decrease of Bax/Bcl-2 ratio. MK prevented progression of cardiac remodeling in the CHF rabbit, likely by activation of anti-apoptotic signaling. Exogenous MK application might be a novel therapeutic strategy for CHF due to non-ischemic origin.

  6. Inhibition of SCF attenuates peribronchial remodeling in chronic cockroach allergen-induced asthma.

    PubMed

    Berlin, Aaron A; Hogaboam, Cory M; Lukacs, Nicholas W

    2006-06-01

    The progression and severity of chronic asthma likely depends upon the intensity of the damage and remodeling of the tissue. We have developed a chronic model of allergic asthma using multiple cockroach allergen challenges. Using this clinically relevant allergen we have established significant peribronchial fibrosis and mucus overproduction. These remodeling events are accompanied by intense peribronchial inflammation, including lymphocytes and eosinophils. A cytokine that has been identified as having a prominent role in short-term allergic events, stem cell factor (SCF), appears to have a significant role in this late-stage process. Using our polyclonal antibody specific for SCF administered into the airways of mice during the final allergen challenges, we find a significant effect on the chronic peribronchial allergen-induced fibrotic remodeling. This was characterized by reduced inflammation, especially eosinophils, as well as reduced hydroxyproline levels in anti-SCF compared to control antibody-treated animals. In addition, when we examined chemokines associated with the chronic disease and neutralized SCF in vivo we observed a corresponding decrease in CCL6 and CCL17. Using an inhibitor, imatinib mesylate, that blocks SCF/c-kit-associated RTK, we find similar results as with anti-SCF for attenuating AHR and fibrotic changes, suggesting that a potential clinical treatment for chronic asthma already exists related to this pathway. These results further support the potential use of SCF/c-kit inhibition for targeting chronic severe asthmatic responses.

  7. Stress-induced structural remodeling in hippocampus: Prevention by lithium treatment

    NASA Astrophysics Data System (ADS)

    Wood, Gwendolyn E.; Young, L. Trevor; Reagan, Lawrence P.; Chen, Biao; McEwen, Bruce S.

    2004-03-01

    Chronic restraint stress, psychosocial stress, as well as systemic or oral administration of the stress-hormone corticosterone induces a morphological reorganization in the rat hippocampus, in which adrenal steroids and excitatory amino acids mediate a reversible remodeling of apical dendrites on CA3 pyramidal cell neurons of the hippocampus. This stress-induced neuronal remodeling is accompanied also by behavioral changes, some of which can be prevented with selective antidepressant and anticonvulsive drug treatments. Lithium is an effective treatment for mood disorders and has neuroprotective effects, which may contribute to its therapeutic properties. Thus, we wanted to determine whether lithium treatment could prevent the effects of chronic stress on CA3 pyramidal cell neuroarchitecture and the associated molecular and behavioral measures. Chronic lithium treatment prevented the stress-induced decrease in dendritic length, as well as the stress-induced increase in glial glutamate transporter 1 (GLT-1) mRNA expression and the phosphorylation of cAMP-response element binding in the hippocampus. Lithium treatment, however, did not prevent stress effects on behavior in the open field or the plus-maze. These data demonstrate that chronic treatment with lithium can protect the hippocampus from potentially deleterious effects of chronic stress on glutamatergic activation, which may be relevant to its therapeutic efficacy in the treatment of major depressive disorder and bipolar disorder.

  8. An Agent-Based Discrete Collagen Fiber Network Model of Dynamic Traction Force-Induced Remodeling.

    PubMed

    Reinhardt, James W; Gooch, Keith

    2017-09-21

    We developed an agent-based model that incorporates repetitively applied traction force within a discrete fiber network to understand how microstructural properties of the network influence mechanical properties and traction force-induced remodeling. An important difference between our model and similar finite-element models is that by implementing more biologically-realistic dynamic traction, we can explore a greater range of matrix remodeling. Here, we validated our model by reproducing qualitative trends observed in three sets of experimental data reported by others: tensile and shear testing of cell-free collagen gels, collagen remodeling around a single isolated cell, and collagen remodeling between pairs of cells. In response to tensile and shear strain, simulated acellular networks exhibited biphasic stress-strain curves indicative of strain-stiffening. Our data support the notion that strain-stiffening might occur as individual fibrils successively align along the axis of strain and become engaged in tension. In simulations with a single, contractile cell, peak collagen displacement occurred closest to the cell and decreased with increasing distance. In simulations with two cells, compaction of collagen between cells appeared inversely related to the initial distance between cells. Further analysis revealed strain energy was relatively uniform around the outer surface of cells separated by 250 microns, but became increasingly non-uniform as the distance between cells decreased. This pattern was partly attributable to the pattern of collagen compaction. These findings are of interest because fibril alignment, density, and strain energy may each contribute to contact guidance during tissue morphogenesis.

  9. Lymphatic vessels regulate immune microenvironments in human and murine melanoma.

    PubMed

    Lund, Amanda W; Wagner, Marek; Fankhauser, Manuel; Steinskog, Eli S; Broggi, Maria A; Spranger, Stefani; Gajewski, Thomas F; Alitalo, Kari; Eikesdal, Hans P; Wiig, Helge; Swartz, Melody A

    2016-09-01

    Lymphatic remodeling in tumor microenvironments correlates with progression and metastasis, and local lymphatic vessels play complex and poorly understood roles in tumor immunity. Tumor lymphangiogenesis is associated with increased immune suppression, yet lymphatic vessels are required for fluid drainage and immune cell trafficking to lymph nodes, where adaptive immune responses are mounted. Here, we examined the contribution of lymphatic drainage to tumor inflammation and immunity using a mouse model that lacks dermal lymphatic vessels (K14-VEGFR3-Ig mice). Melanomas implanted in these mice grew robustly, but exhibited drastically reduced cytokine expression and leukocyte infiltration compared with those implanted in control animals. In the absence of local immune suppression, transferred cytotoxic T cells more effectively controlled tumors in K14-VEGFR3-Ig mice than in control mice. Furthermore, gene expression analysis of human melanoma samples revealed that patient immune parameters are markedly stratified by levels of lymphatic markers. This work suggests that the establishment of tumor-associated inflammation and immunity critically depends on lymphatic vessel remodeling and drainage. Moreover, these results have implications for immunotherapies, the efficacies of which are regulated by the tumor immune microenvironment.

  10. Lymphatic vessels regulate immune microenvironments in human and murine melanoma

    PubMed Central

    Lund, Amanda W.; Wagner, Marek; Fankhauser, Manuel; Steinskog, Eli S.; Broggi, Maria A.; Spranger, Stefani; Gajewski, Thomas F.; Alitalo, Kari; Eikesdal, Hans P.

    2016-01-01

    Lymphatic remodeling in tumor microenvironments correlates with progression and metastasis, and local lymphatic vessels play complex and poorly understood roles in tumor immunity. Tumor lymphangiogenesis is associated with increased immune suppression, yet lymphatic vessels are required for fluid drainage and immune cell trafficking to lymph nodes, where adaptive immune responses are mounted. Here, we examined the contribution of lymphatic drainage to tumor inflammation and immunity using a mouse model that lacks dermal lymphatic vessels (K14-VEGFR3-Ig mice). Melanomas implanted in these mice grew robustly, but exhibited drastically reduced cytokine expression and leukocyte infiltration compared with those implanted in control animals. In the absence of local immune suppression, transferred cytotoxic T cells more effectively controlled tumors in K14-VEGFR3-Ig mice than in control mice. Furthermore, gene expression analysis of human melanoma samples revealed that patient immune parameters are markedly stratified by levels of lymphatic markers. This work suggests that the establishment of tumor-associated inflammation and immunity critically depends on lymphatic vessel remodeling and drainage. Moreover, these results have implications for immunotherapies, the efficacies of which are regulated by the tumor immune microenvironment. PMID:27525437

  11. Adenosine triphosphate-induced photoreceptor death and retinal remodeling in rats

    PubMed Central

    Vessey, Kirstan A; Greferath, Ursula; Aplin, Felix P; Jobling, Andrew I; Phipps, Joanna A; Ho, Tracy; De Iongh, Robbert U; Fletcher, Erica L

    2014-01-01

    Many common causes of blindness involve the death of retinal photoreceptors, followed by progressive inner retinal cell remodeling. For an inducible model of retinal degeneration to be useful, it must recapitulate these changes. Intravitreal administration of adenosine triphosphate (ATP) has recently been found to induce acute photoreceptor death. The aim of this study was to characterize the chronic effects of ATP on retinal integrity. Five-week-old, dark agouti rats were administered 50 mM ATP into the vitreous of one eye and saline into the other. Vision was assessed using the electroretinogram and optokinetic response and retinal morphology investigated via histology. ATP caused significant loss of visual function within 1 day and loss of 50% of the photoreceptors within 1 week. At 3 months, 80% of photoreceptor nuclei were lost, and total photoreceptor loss occurred by 6 months. The degeneration and remodeling were similar to those found in heritable retinal dystrophies and age-related macular degeneration and included inner retinal neuronal loss, migration, and formation of new synapses; Müller cell gliosis, migration, and scarring; blood vessel loss; and retinal pigment epithelium migration. In addition, extreme degeneration and remodeling events, such as neuronal and glial migration outside the neural retina and proliferative changes in glial cells, were observed. These extreme changes were also observed in the 2-year-old P23H rhodopsin transgenic rat model of retinitis pigmentosa. This ATP-induced model of retinal degeneration may provide a valuable tool for developing pharmaceutical therapies or for testing electronic implants aimed at restoring vision. J. Comp. Neurol. 522:2928–2950, 2014. © 2014 Wiley Periodicals, Inc. PMID:24639102

  12. Estrogen inhibits mast cell chymase release to prevent pressure overload-induced adverse cardiac remodeling.

    PubMed

    Li, Jianping; Jubair, Shaiban; Janicki, Joseph S

    2015-02-01

    Estrogen regulation of myocardial chymase and chymase effects on cardiac remodeling are unknown. To test the hypothesis that estrogen prevents pressure overload-induced adverse cardiac remodeling by inhibiting mast cell (MC) chymase release, transverse aortic constriction or sham surgery was performed in 7-week-old intact and ovariectomized (OVX) rats. Three days before creating the constriction, additional groups of OVX rats began receiving 17β-estradiol, a chymase inhibitor, or a MC stabilizer. Left ventricular function, cardiomyocyte size, collagen volume fraction, MC density and degranulation, and myocardial and plasma chymase levels were assessed 18 days postsurgery. Aortic constriction resulted in ventricular hypertrophy in intact and OVX groups, whereas collagen volume fraction was increased only in OVX rats. Chymase protein content was increased by aortic constriction in the intact and OVX groups, with the magnitude of the increase being greater in OVX rats. MC density and degranulation, plasma chymase levels, and myocardial active transforming growth factor-β1 levels were increased by aortic constriction only in OVX rats. Estrogen replacement markedly attenuated the constriction-increased myocardial chymase, MC density and degranulation, plasma chymase, and myocardial active transforming growth factor-β1, as well as prevented ventricular hypertrophy and increased collagen volume fraction. Chymostatin attenuated the aortic constriction-induced ventricular hypertrophy and collagen volume fraction in the OVX rats similar to that achieved by estrogen replacement. Nedocromil yielded similar effects, except for the reduction of chymase content. We conclude that the estrogen-inhibited release of MC chymase is responsible for the cardioprotection against transverse aortic constriction-induced adverse cardiac remodeling.

  13. Regulation of Extracellular Matrix Remodeling Proteins by Osteoblasts in Titanium Nanoparticle-Induced Aseptic Loosening Model.

    PubMed

    Xie, Jing; Hou, Yanhua; Fu, Na; Cai, Xiaoxiao; Li, Guo; Peng, Qiang; Lin, Yunfeng

    2015-10-01

    Titanium (Ti)-wear particles, formed at the bone-implant interface, are responsible for aseptic loosening, which is a main cause of total joint replacement failure. There have been many studies on Ti particle-induced function changes in mono-cultured osteoblasts and synovial cells. However, little is known on extracellular matrix remodeling displayed by osteoblasts when in coexistence with Synovial cells. To further mimic the bone-implant interface environment, we firstly established a nanoscaled-Ti particle-induced aseptic loosening system by co-culturing osteoblasts and Synovial cells. We then explored the impact of the Synovial cells on Ti particle-engulfed osteoblasts in the mimicked flamed niche. The matrix metalloproteinases and lysyl oxidases expression levels, two protein families which are critical in osseointegration, were examined under induction by tumor necrosis factor-alpha. It was found that the co-culture between the osteoblasts and Synovial cells markedly increased the migration and proliferation of the osteoblasts, even in the Ti-particle engulfed osteoblasts. Importantly, the Ti-particle engulfed osteoblasts, induced by TNF-alpha after the co-culture, enhanced the release of the matrix metalloproteinases and reduced the expressions of lysyl oxidases. The regulation of extracellular matrix remodeling at the protein level was further assessed by investigations on gene expression of the matrix metalloproteinases and lysyl oxidases, which also suggested that the regulation started at the genetic level. Our research work has therefore revealed the critical role of multi cell-type interactions in the extracellular matrix remodeling within the peri-prosthetic tissues, which provides new insights on aseptic loosening and brings new clues about incomplete osseointegration between the implantation materials and their surrounding bones.

  14. Adenosine triphosphate-induced photoreceptor death and retinal remodeling in rats.

    PubMed

    Vessey, Kirstan A; Greferath, Ursula; Aplin, Felix P; Jobling, Andrew I; Phipps, Joanna A; Ho, Tracy; De Iongh, Robbert U; Fletcher, Erica L

    2014-09-01

    Many common causes of blindness involve the death of retinal photoreceptors, followed by progressive inner retinal cell remodeling. For an inducible model of retinal degeneration to be useful, it must recapitulate these changes. Intravitreal administration of adenosine triphosphate (ATP) has recently been found to induce acute photoreceptor death. The aim of this study was to characterize the chronic effects of ATP on retinal integrity. Five-week-old, dark agouti rats were administered 50 mM ATP into the vitreous of one eye and saline into the other. Vision was assessed using the electroretinogram and optokinetic response and retinal morphology investigated via histology. ATP caused significant loss of visual function within 1 day and loss of 50% of the photoreceptors within 1 week. At 3 months, 80% of photoreceptor nuclei were lost, and total photoreceptor loss occurred by 6 months. The degeneration and remodeling were similar to those found in heritable retinal dystrophies and age-related macular degeneration and included inner retinal neuronal loss, migration, and formation of new synapses; Müller cell gliosis, migration, and scarring; blood vessel loss; and retinal pigment epithelium migration. In addition, extreme degeneration and remodeling events, such as neuronal and glial migration outside the neural retina and proliferative changes in glial cells, were observed. These extreme changes were also observed in the 2-year-old P23H rhodopsin transgenic rat model of retinitis pigmentosa. This ATP-induced model of retinal degeneration may provide a valuable tool for developing pharmaceutical therapies or for testing electronic implants aimed at restoring vision.

  15. Structural Basis for Host Membrane Remodeling Induced by Protein 2B of Hepatitis A Virus

    PubMed Central

    Vives-Adrián, Laia; Garriga, Damià; Buxaderas, Mònica; Fraga, Joana; Pereira, Pedro José Barbosa

    2015-01-01

    ABSTRACT The complexity of viral RNA synthesis and the numerous participating factors require a mechanism to topologically coordinate and concentrate these multiple viral and cellular components, ensuring a concerted function. Similarly to all other positive-strand RNA viruses, picornaviruses induce rearrangements of host intracellular membranes to create structures that act as functional scaffolds for genome replication. The membrane-targeting proteins 2B and 2C, their precursor 2BC, and protein 3A appear to be primarily involved in membrane remodeling. Little is known about the structure of these proteins and the mechanisms by which they induce massive membrane remodeling. Here we report the crystal structure of the soluble region of hepatitis A virus (HAV) protein 2B, consisting of two domains: a C-terminal helical bundle preceded by an N-terminally curved five-stranded antiparallel β-sheet that displays striking structural similarity to the β-barrel domain of enteroviral 2A proteins. Moreover, the helicoidal arrangement of the protein molecules in the crystal provides a model for 2B-induced host membrane remodeling during HAV infection. IMPORTANCE No structural information is currently available for the 2B protein of any picornavirus despite it being involved in a critical process in viral factory formation: the rearrangement of host intracellular membranes. Here we present the structure of the soluble domain of the 2B protein of hepatitis A virus (HAV). Its arrangement, both in crystals and in solution under physiological conditions, can help to understand its function and sheds some light on the membrane rearrangement process, a putative target of future antiviral drugs. Moreover, this first structure of a picornaviral 2B protein also unveils a closer evolutionary relationship between the hepatovirus and enterovirus genera within the Picornaviridae family. PMID:25589659

  16. Mesenchymal stem cells attenuate vascular remodeling in monocrotaline-induced pulmonary hypertension rats.

    PubMed

    Xie, Jiang; Hu, Dayi; Niu, Lili; Qu, Suping; Wang, Shenghao; Liu, Shuang

    2012-12-01

    Intravenous and intratracheal implantation of mesenchymal stem cells (MSCs) may offer ameliorating effects on pulmonary hypertension (PH) induced by monocrotaline (MCT) in rats. The aim of this study was to examine the anti-remodeling effect of intravenous MSCs (VMSCs) and intratracheal MSCs (TMSCs) in rats with PH, and the underlying mechanisms. MSCs were isolated from rat bone marrow and cultured. PH was induced in rats by intraperitoneal injection of MCT. One week after MCT administration, the rats were divided into 3 groups in terms of different treatments: VMSCs group (intravenous injection of MSCs), TMSCs group (intratracheal injection of MSCs), PH group (no treatment given). Those receiving saline instead of MCT served as negative control (control group). Pulmonary arterial structure was pathologically observed, pulmonary arterial dynamics measured, and remodeling-associated cytokines Smad2 and Smad3 detected in the lungs, three weeks after MCT injection. The results showed that PH group versus control group had higher pulmonary arterial pressure (PAP) and wall thickness index (WTI) 21 days after MCT treatment. The expression of phosphorylated (p)-Smad2 and the ratio of p-Smad2/Smad2 were much higher in PH group than in control group. Fluorescence-labeled MSCs were extensively distributed in rats' lungs in VMSCs and TMSCs groups 3 and 14 days after transplantation, but not found in the media of the pulmonary artery. WTI and PAP were significantly lower in both VMSCs and TMSCs groups than in PH group three weeks after MCT injection. The p-Smad2 expression and the ratio of p-Smad2/Smad2 were obviously reduced in VMSCs and TMSCs groups as compared with those in PH group. In conclusion, both intravenous and intratracheal transplantation of MSCs can attenuate PAP and pulmonary artery remodeling in MCT-induced PH rats, which may be associated with the early suppression of Smad2 phosphorylation via paracrine pathways.

  17. Annexin-I as a potential target for green tea extract induced actin remodeling.

    PubMed

    Xiao, Gui-Shan; Jin, Yu-Sheng; Lu, Qing-Yi; Zhang, Zuo-Feng; Belldegrun, Arie; Figlin, Robert; Pantuck, Allan; Yen, Yun; Li, Frederick; Rao, Jianyu

    2007-01-01

    Using a multistep human urothelial model, we previously showed that green tea extract (GTE) selectively modulates actin remodeling in transformed cells (MC-T11), which resulted in increased cell adhesion and reduced cell motility (Lu et al., Clin Cancer Res 2005;11:1675-83). This study further analyzed which actin binding proteins (ABPs) might be involved in this process. Proteomic profiles of GTE treated and untreated MC-T11 cells using two-dimensional gel electrophoresis coupled with liquid chromatography tandem mass spectrometry (LC/MS/MS) and matrix-assisted laser desorption and ionization time-of-flight (MALDI-TOF) identified 20 GTE-induced proteins. Among them, 3 were ABPs (tropomodulin, cofilin and annexin-I), and only annexin-I showed a dose- and time-dependent expression. The increased annexin-I correlated with actin remodeling, and was the result of transcription level up-regulation, as determined by RT-PCR, pull-down immunoblot and siRNA analyses. 5-Azacytidine, a DNA methylation inhibitor, exhibited no effect on annexin-I expression when used alone, but had an additive effect for GTE-induced annexin-I expression. Immunohistochemistry of bladder cancer tissue array showed a decrease of annexin-I expression in carcinoma in situ and low grade papillary carcinoma (n = 32, 0% positive) compared to nontumor urothelium (n = 18, 89% positive) (p < 0.001 by Fisher exact test), but increased in some (6 of 15, 40%) high-grade tumors. Together, GTE induced annexin-I expression plays a role in regulating actin remodeling and decreased annexin-I expression is a common event in early stage of bladder cancer development.

  18. Featured Article: Cardioprotective effects of lysyl oxidase inhibition against volume overload-induced extracellular matrix remodeling

    PubMed Central

    El Hajj, Elia C; El Hajj, Milad C; Ninh, Van K

    2015-01-01

    A hallmark of heart failure (HF) is adverse extracellular matrix (ECM) remodeling, which is regulated by the collagen cross-linking enzyme, lysyl oxidase (LOX). In this study, we evaluate the efficacy of LOX inhibition to prevent adverse left ventricular (LV) remodeling and dysfunction using an experimental model of HF. Sprague–Dawley rats were subjected to surgically induced volume overload (VO) by creation of aortocaval fistula (ACF). A LOX inhibitor, beta-aminopropionitrile (BAPN; 100 mg/kg/day), was administered to rats with ACF or sham surgery at eight weeks postsurgery. Echocardiography was used to assess progressive alterations in cardiac ventricular structure and function. Left ventricular (LV) catheterization was used to assess alterations in contractility, stiffness, LV pressure and volume, and other indices of cardiac function. The LV ECM alterations were assessed by: (a) histological staining of collagen, (b) protein expression of collagen types I and III, (c) hydroxyproline assay, and (d) cross-linking assay. LOX inhibition attenuated VO-induced increases in cardiac stress, and attenuated increases in interstitial myocardial collagen, total collagen, and protein levels of collagens I and III. Both echocardiography and catheterization measurements indicated improved cardiac function post-VO in BAPN treated rats vs. untreated. Inhibition of LOX attenuated VO-induced decreases in LV stiffness and cardiac function. Overall, our data indicate that LOX inhibition was cardioprotective in the volume overloaded heart. PMID:26582054

  19. Structural and functional remodeling of skeletal muscle microvasculature is induced by simulated microgravity

    NASA Technical Reports Server (NTRS)

    Delp, M. D.; Colleran, P. N.; Wilkerson, M. K.; McCurdy, M. R.; Muller-Delp, J.

    2000-01-01

    Hindlimb unloading of rats results in a diminished ability of skeletal muscle arterioles to constrict in vitro and elevate vascular resistance in vivo. The purpose of the present study was to determine whether alterations in the mechanical environment (i.e., reduced fluid pressure and blood flow) of the vasculature in hindlimb skeletal muscles from 2-wk hindlimb-unloaded (HU) rats induces a structural remodeling of arterial microvessels that may account for these observations. Transverse cross sections were used to determine media cross-sectional area (CSA), wall thickness, outer perimeter, number of media nuclei, and vessel luminal diameter of feed arteries and first-order (1A) arterioles from soleus and the superficial portion of gastrocnemius muscles. Endothelium-dependent dilation (ACh) was also determined. Media CSA of resistance arteries was diminished by hindlimb unloading as a result of decreased media thickness (gastrocnemius muscle) or reduced vessel diameter (soleus muscle). ACh-induced dilation was diminished by 2 wk of hindlimb unloading in soleus 1A arterioles, but not in gastrocnemius 1A arterioles. These results indicate that structural remodeling and functional adaptations of the arterial microvasculature occur in skeletal muscles of the HU rat; the data suggest that these alterations may be induced by reductions in transmural pressure (gastrocnemius muscle) and wall shear stress (soleus muscle).

  20. Cardioprotective effects of lysyl oxidase inhibition against volume overload-induced extracellular matrix remodeling.

    PubMed

    El Hajj, Elia C; El Hajj, Milad C; Ninh, Van K; Gardner, Jason D

    2016-03-01

    A hallmark of heart failure (HF) is adverse extracellular matrix (ECM) remodeling, which is regulated by the collagen cross-linking enzyme, lysyl oxidase (LOX). In this study, we evaluate the efficacy of LOX inhibition to prevent adverse left ventricular (LV) remodeling and dysfunction using an experimental model of HF. Sprague-Dawley rats were subjected to surgically induced volume overload (VO) by creation of aortocaval fistula (ACF). A LOX inhibitor, beta-aminopropionitrile (BAPN; 100 mg/kg/day), was administered to rats with ACF or sham surgery at eight weeks postsurgery. Echocardiography was used to assess progressive alterations in cardiac ventricular structure and function. Left ventricular (LV) catheterization was used to assess alterations in contractility, stiffness, LV pressure and volume, and other indices of cardiac function. The LV ECM alterations were assessed by: (a) histological staining of collagen, (b) protein expression of collagen types I and III, (c) hydroxyproline assay, and (d) cross-linking assay. LOX inhibition attenuated VO-induced increases in cardiac stress, and attenuated increases in interstitial myocardial collagen, total collagen, and protein levels of collagens I and III. Both echocardiography and catheterization measurements indicated improved cardiac function post-VO in BAPN treated rats vs. untreated. Inhibition of LOX attenuated VO-induced decreases in LV stiffness and cardiac function. Overall, our data indicate that LOX inhibition was cardioprotective in the volume overloaded heart.

  1. Inhibition of farnesyl pyrophosphate synthase improves pressure overload induced chronic cardiac remodeling

    PubMed Central

    Zhao, Chen-Ze; Zhao, Xu-Ming; Yang, Jian; Mou, Yun; Chen, Bin; Wu, Huan-Dong; Dai, Dong-Pu; Ding, Jie; Hu, Shen-Jiang

    2016-01-01

    Farnesyl pyrophosphate synthase (FPPS) is a key enzyme in the mevalonate pathway. In our previous studies, we find that inhibition of FPPS attenuates angiotensin II-induced cardiac hypertrophy and fibrosis by suppressing RhoA while FPPS and Ras are up-regulated in pressure overload rats. In this study, we evaluate the effects and mechanisms of FPPS inhibition in pressure overload mice. Male FPPS-small interfering RNA (SiRNA) transgenic (Tg) mice and non-transgenic littermate control (NLC) were randomly divided into suprarenal abdominal aortic constriction (AAC) group and sham operation group. 12 weeks following AAC, mice were sacrificed by cervical dislocation. Histological and echocardiographic assessments showed that inhibition of FPPS improved chronic cardiac remodeling which was induced by AAC. The reductions of Ras farnesylation and GTP-Ras, as well as their downstream extracellular signal-related kinases 1/2 (ERK1/2) expression were observed in the heart of Tg-AAC mice compared with NLC-AAC mice, along with the reduction of fetal gene expression. We provide here important experimental evidence that inhibition of FPPS improves AAC induced chronic cardiac remodeling and fibrosis by the reduction of farnesylated Ras and the downregulation of Ras-ERK1/2 pathway. PMID:28008986

  2. Structural and functional remodeling of skeletal muscle microvasculature is induced by simulated microgravity

    NASA Technical Reports Server (NTRS)

    Delp, M. D.; Colleran, P. N.; Wilkerson, M. K.; McCurdy, M. R.; Muller-Delp, J.

    2000-01-01

    Hindlimb unloading of rats results in a diminished ability of skeletal muscle arterioles to constrict in vitro and elevate vascular resistance in vivo. The purpose of the present study was to determine whether alterations in the mechanical environment (i.e., reduced fluid pressure and blood flow) of the vasculature in hindlimb skeletal muscles from 2-wk hindlimb-unloaded (HU) rats induces a structural remodeling of arterial microvessels that may account for these observations. Transverse cross sections were used to determine media cross-sectional area (CSA), wall thickness, outer perimeter, number of media nuclei, and vessel luminal diameter of feed arteries and first-order (1A) arterioles from soleus and the superficial portion of gastrocnemius muscles. Endothelium-dependent dilation (ACh) was also determined. Media CSA of resistance arteries was diminished by hindlimb unloading as a result of decreased media thickness (gastrocnemius muscle) or reduced vessel diameter (soleus muscle). ACh-induced dilation was diminished by 2 wk of hindlimb unloading in soleus 1A arterioles, but not in gastrocnemius 1A arterioles. These results indicate that structural remodeling and functional adaptations of the arterial microvasculature occur in skeletal muscles of the HU rat; the data suggest that these alterations may be induced by reductions in transmural pressure (gastrocnemius muscle) and wall shear stress (soleus muscle).

  3. Arabidopsis FORGETTER1 mediates stress-induced chromatin memory through nucleosome remodeling

    PubMed Central

    Brzezinka, Krzysztof; Altmann, Simone; Czesnick, Hjördis; Nicolas, Philippe; Gorka, Michal; Benke, Eileen; Kabelitz, Tina; Jähne, Felix; Graf, Alexander; Kappel, Christian; Bäurle, Isabel

    2016-01-01

    Plants as sessile organisms can adapt to environmental stress to mitigate its adverse effects. As part of such adaptation they maintain an active memory of heat stress for several days that promotes a more efficient response to recurring stress. We show that this heat stress memory requires the activity of the FORGETTER1 (FGT1) locus, with fgt1 mutants displaying reduced maintenance of heat-induced gene expression. FGT1 encodes the Arabidopsis thaliana orthologue of Strawberry notch (Sno), and the protein globally associates with the promoter regions of actively expressed genes in a heat-dependent fashion. FGT1 interacts with chromatin remodelers of the SWI/SNF and ISWI families, which also display reduced heat stress memory. Genomic targets of the BRM remodeler overlap significantly with FGT1 targets. Accordingly, nucleosome dynamics at loci with altered maintenance of heat-induced expression are affected in fgt1. Together, our results suggest that by modulating nucleosome occupancy, FGT1 mediates stress-induced chromatin memory. DOI: http://dx.doi.org/10.7554/eLife.17061.001 PMID:27680998

  4. Nitrosonifedipine ameliorates angiotensin II-induced vascular remodeling via antioxidative effects.

    PubMed

    Sakurada, Takumi; Ishizawa, Keisuke; Imanishi, Masaki; Izawa-Ishizawa, Yuki; Fujii, Shoko; Tominaga, Erika; Tsuneishi, Teppei; Horinouchi, Yuya; Kihira, Yoshitaka; Ikeda, Yasumasa; Tomita, Shuhei; Aihara, Ken-ichi; Minakuchi, Kazuo; Tsuchiya, Koichiro; Tamaki, Toshiaki

    2013-01-01

    Nifedipine is unstable under light and decomposes to a stable nitroso analog, nitrosonifedipine (NO-NIF). The ability of NO-NIF to block calcium channels is quite weak compared with that of nifedipine. Recently, we have demonstrated that NO-NIF reacts with unsaturated fatty acid leading to generate NO-NIF radical, which acquires radical scavenging activity. However, the effects of NO-NIF on the pathogenesis related with oxidative stress, such as atherosclerosis and hypertension, are unclear. In this study, we investigated the effects of NO-NIF on angiotensin II (Ang II)-induced vascular remodeling. Ang II-induced thickening and fibrosis of aorta were inhibited by NO-NIF in mice. NO-NIF decreased reactive oxygen species (ROS) in the aorta and urinary 8-hydroxy-20-deoxyguanosine. Ang II-stimulated mRNA expressions of p22(phox), CD68, F4/80, monocyte chemoattractant protein-1, and collagen I in the aorta were inhibited by NO-NIF. Moreover, NO-NIF inhibited Ang II-induced cell migration and proliferation of vascular smooth muscle cells (VSMCs). NO-NIF reduced Ang II-induced ROS to the control level detected by dihydroethidium staining and lucigenin chemiluminescence assay in VSMCs. NO-NIF suppressed phosphorylations of Akt and epidermal growth factor receptor induced by Ang II. However, NO-NIF had no effects on intracellular Ca(2+) increase and protein kinase C-δ phosphorylation induced by Ang II in VSMCs. The electron paramagnetic resonance spectra indicated the continuous generation of NO-NIF radical of reaction with cultured VSMCs. These findings suggest that NO-NIF improves Ang II-induced vascular remodeling via the attenuation of oxidative stress.

  5. Imaging the lymphatic system.

    PubMed

    Munn, Lance L; Padera, Timothy P

    2014-11-01

    Visualization of the lymphatic system is clinically necessary during diagnosis or treatment of many conditions and diseases; it is used for identifying and monitoring lymphedema, for detecting metastatic lesions during cancer staging and for locating lymphatic structures so they can be spared during surgical procedures. Imaging lymphatic anatomy and function also plays an important role in experimental studies of lymphatic development and function, where spatial resolution and accessibility are better. Here, we review technologies for visualizing and imaging the lymphatic system for clinical applications. We then describe the use of lymphatic imaging in experimental systems as well as some of the emerging technologies for improving these methodologies. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Pulmonary arterial strain- and remodeling-induced stiffening are differentiated in a chronic model of pulmonary hypertension.

    PubMed

    Golob, Mark J; Tabima, Diana M; Wolf, Gregory D; Johnston, James L; Forouzan, Omid; Mulchrone, Ashley M; Kellihan, Heidi B; Bates, Melissa L; Chesler, Naomi C

    2017-04-11

    Pulmonary hypertension (PH) is a debilitating vascular disease that leads to pulmonary artery (PA) stiffening, which is a predictor of patient mortality. During PH development, PA stiffening adversely affects right ventricular function. PA stiffening has been investigated through the arterial nonlinear elastic response during mechanical testing using a canine PH model. However, only circumferential properties were reported and in the absence of chronic PH-induced PA remodeling. Remodeling can alter arterial nonlinear elastic properties via chronic changes in extracellular matrix (ECM) content and geometry. Here, we used an established constitutive model to demonstrate and differentiate between strain-stiffening, which is due to nonlinear elasticity, and remodeling-induced stiffening, which is due to ECM and geometric changes, in a canine model of chronic thromboembolic PH (CTEPH). To do this, circumferential and axial tissue strips of large extralobar PAs from control and CTEPH tissues were tested in uniaxial tension, and data were fit to a phenomenological constitutive model. Strain-induced stiffening was evident from mechanical testing as nonlinear elasticity in both directions and computationally by a high correlation coefficient between the mechanical data and model (R(2)=0.89). Remodeling-induced stiffening was evident from a significant increase in the constitutive model stress parameter, which correlated with increased PA collagen content and decreased PA elastin content as measured histologically. The ability to differentiate between strain- and remodeling-induced stiffening in vivo may lead to tailored clinical treatments for PA stiffening in PH patients.

  7. Targeting AMCase reduces esophageal eosinophilic inflammation and remodeling in a mouse model of egg induced eosinophilic esophagitis.

    PubMed

    Cho, Jae Youn; Rosenthal, Peter; Miller, Marina; Pham, Alexa; Aceves, Seema; Sakuda, Shohei; Broide, David H

    2014-01-01

    Studies of AMCase inhibition in mouse models of lung eosinophilic inflammation have produced conflicting results with some studies demonstrating inhibition of eosinophilic inflammation and others not. No studies have investigated the role of AMCase inhibition in eosinophilic esophagitis (EoE). We have used a mouse model of egg (OVA) induced EoE to determine whether pharmacologic inhibition of AMCase with allosamidin reduced eosinophilic inflammation and remodeling in the esophagus in EoE. Administration of intra-esophageal OVA for 6weeks to BALB/c mice induced increased levels of esophageal eosinophils, mast cells, and features of esophageal remodeling (fibrosis, basal zone hyperplasia, deposition of the extracellular matrix protein fibronectin). Administration of intraperitoneal (ip) allosamidin to BALB/c mice significantly inhibited AMCase enzymatic activity in the esophagus. Pharmacologic inhibition of AMCase with ip allosamidin inhibited both OVA induced increases in esophageal eosinophilic inflammation and OVA induced esophageal remodeling (fibrosis, epithelial basal zone hyperplasia, extracellular matrix deposition of fibronectin). This inhibition of eosinophilic inflammation in the esophagus by ip allosamidin was associated with reduced eotaxin-1 expression in the esophagus. Oral allosamidin inhibited eosinophilic inflammation in the epithelium but did not inhibit esophageal remodeling. These studies suggest that pharmacologic inhibition of AMCase results in inhibition of eosinophilic inflammation and remodeling in the esophagus in a mouse model of egg induced EoE partially through effects in the esophagus on reducing chemokines (i.e. eotaxin-1) implicated in the pathogenesis of EoE.

  8. Semaphorin 4D induces vaginal epithelial cell apoptosis to control mouse postnatal vaginal tissue remodeling.

    PubMed

    Ito, Takuji; Bai, Tao; Tanaka, Tetsuji; Yoshida, Kenji; Ueyama, Takashi; Miyajima, Masayasu; Negishi, Takayuki; Kawasaki, Takahiko; Takamatsu, Hyota; Kikutani, Hitoshi; Kumanogoh, Atsushi; Yukawa, Kazunori

    2015-02-01

    The opening of the mouse vaginal cavity to the skin is a postnatal tissue remodeling process that occurs at approximately five weeks of age for the completion of female genital tract maturation at puberty. The tissue remodeling process is primarily composed of a hormonally triggered apoptotic process predominantly occurring in the epithelium of the distal section of the vaginal cavity. However, the detailed mechanism underlying the apoptotic induction remains to be elucidated. In the present study, it was observed that the majority of BALB/c mice lacking the class 4 semaphorin, semaphorin 4D (Sema4D), developed imperforate vagina and hydrometrocolpos resulting in a perpetually unopened vaginal cavity regardless of a normal estrogen level comparable with that in wild‑type (WT) mice. Administration of β‑estradiol to infant Sema4D‑deficient (Sema4D‑/‑) mice did not induce precocious vaginal opening, which was observed in WT mice subjected to the same β‑estradiol administration, excluding the possibility that the closed vaginal phenotype was due to insufficient estrogen secretion at the time of vaginal opening. In order to assess the role of Sema4D in the postnatal vaginal tissue remodeling process, the expression of Sema4D and its receptor, plexin‑B1, was examined as well as the level of apoptosis in the vaginal epithelia of five‑week‑old WT and Sema4D‑/‑ mice. Immunohistochemical analyses confirmed the localization of Sema4D and plexin‑B1 in the mouse vaginal epithelia. Terminal deoxynucleotidyl transferase dUTP nick end labeling assay and immunohistochemistry detecting activated caspase‑3 revealed significantly fewer apoptotic cells in situ in the vaginal mucosa of five‑week‑old Sema4D‑/‑ mice compared with WT mice. The addition of recombinant Sema4D to Sema4D‑/‑ vaginal epithelial cells in culture significantly enhanced apoptosis of the vaginal epithelial cells, demonstrating the apoptosis‑inducing activity of Sema4D. The

  9. Wnt5a attenuates hypoxia-induced pulmonary arteriolar remodeling and right ventricular hypertrophy in mice

    PubMed Central

    Jin, Yuling; Wang, Wang; Chai, Sanbao; Liu, Jie

    2015-01-01

    Hypoxic pulmonary hypertension (HPH), which is characterized by pulmonary arteriolar remodeling and right ventricular hypertrophy, is still a life-threatening disease with the current treatment strategies. The underlying molecular mechanisms of HPH remain unclear. Our previously published study showed that Wnt5a, one of the ligands in the Wnt family, was critically involved in the inhibition of hypoxia-induced pulmonary arterial smooth muscle cell proliferation by downregulation of β-catenin/cyclin D1 in vitro. In this study, we investigated the possible functions and mechanisms of Wnt5a in HPH in vivo. Recombinant mouse Wnt5a (rmWnt5a) or phosphate buffered saline (PBS) was administered to male C57/BL6 mice weekly from the first day to the end of the two or four weeks after exposed to hypoxia (10% O2). Hypoxia-induced pulmonary hypertension was associated with a marked increase in β-catenin/cyclin D1 expression in lungs. Right ventricular systolic pressure and right ventricular hypertrophy index were reduced in animals treated with rmWnt5a compared with PBS. Histology showed less pulmonary vascular remodeling and right ventricular hypertrophy in the group treated with rmWnt5a than with PBS. Treatment with rmWnt5a resulted in a concomitant reduction in β-catenin/cyclin D1 levels in lungs. These data demonstrate that Wnt5a exerts its beneficial effects on HPH by regulating pulmonary vascular remodeling and right ventricular hypertrophy in a manner that is associated with reduction in β-catenin/cyclin D1 signaling. A therapy targeting the β-catenin/cyclin D1 signaling pathway might be a potential strategy for HPH treatment. PMID:25956683

  10. Pioglitazone alleviates cardiac and vascular remodelling and improves survival in monocrotaline induced pulmonary arterial hypertension.

    PubMed

    Behringer, Arnica; Trappiel, Manuela; Berghausen, Eva Maria; Ten Freyhaus, Henrik; Wellnhofer, Ernst; Odenthal, Margarete; Blaschke, Florian; Er, Fikret; Gassanov, Natig; Rosenkranz, Stephan; Baldus, Stephan; Kappert, Kai; Caglayan, Evren

    2016-04-01

    Pulmonary arterial hypertension (PAH) is a fatal disease with limited therapeutic options. Pathophysiological changes comprise obliterative vascular remodelling of small pulmonary arteries, elevated mean pulmonary arterial systolic pressure (PASP) due to elevated resistance of pulmonary vasculature, adverse right ventricular remodelling, and heart failure. Recent findings also indicate a role of increased inflammation and insulin resistance underlying the development of PAH. We hypothesized that treatment of this condition with the peroxisome proliferator-activated receptor-γ (PPARγ) activator pioglitazone, known to regulate the expression of different genes addressing insulin resistance, inflammatory changes, and vascular remodelling, could be a beneficial approach. PAH was induced in adult rats by a single subcutaneous injection of monocrotaline (MCT). Pioglitazone was administered for 2 weeks starting 3 weeks after MCT-injection. At day 35, hemodynamics, organ weights, and -indices were measured. We performed morphological and molecular characterization of the pulmonary vasculature, including analysis of the degree of muscularization, proliferation rates, and medial wall thickness of the small pulmonary arteries. Furthermore, markers of cardiac injury, collagen content, and cardiomyocyte size were analyzed. Survival rates were monitored throughout the experimental period. Pioglitazone treatment improved survival, reduced PASP, muscularization of small pulmonary arteries, and medial wall thickness. Further, MCT-induced right ventricular hypertrophy and fibrosis were attenuated. This was accompanied with reduced cardiac expression of brain natriuretic peptide, as well as decreased cardiomyocyte size. Finally, pulmonary macrophage content and osteopontin gene expression were attenuated. Based on the beneficial impact of pioglitazone, activation of PPARγ might be a promising treatment option in PAH.

  11. Lymphangiogenesis in myocardial remodelling after infarction.

    PubMed

    Ishikawa, Y; Akishima-Fukasawa, Y; Ito, K; Akasaka, Y; Tanaka, M; Shimokawa, R; Kimura-Matsumoto, M; Morita, H; Sato, S; Kamata, I; Ishii, T

    2007-09-01

    The lymphatic system is involved in fluid homeostasis of the cardiac interstitium, but lymphangiogenesis in myocardial remodelling has not previously been examined histopathologically. The aim was to investigate by D2-40 immunohistochemistry the sequential changes in lymphatic distribution in the process of myocardial remodelling after myocardial infarction (MI). Myocardial tissues in various phases of healing after MI were obtained from 40 autopsied hearts. D2-40+ lymphatic vessel density (LD) and CD34+ blood vessel density (BD) in the lesion were determined. BD decreased with advance of myocardial necrosis, subsequently increased at the early stage of granulation and thereafter decreased with the progression of scar formation. In contrast, lymphatic vessels were not detected in lesions with coagulation necrosis, and newly formed lymphatics first appeared in the early stages of granulation. A subsequent increase in LD was demonstrated in the late stages of granulation, and lymphatics remained up to the scar phase. Vascular endothelial growth factor-C was consistently expressed in viable cardiomyocytes around the lesion in all of these stages. In myocardial remodelling after MI, lymphangiogenesis lags behind blood vessel angiogenesis; newly formed lymphatics may be involved mainly in the maturation of fibrosis and scar formation through the drainage of excessive proteins and fluid.

  12. Towards the prediction of flow-induced shear stress distributions experienced by breast cancer cells in the lymphatics.

    PubMed

    Morley, S T; Newport, D T; Walsh, M T

    2017-07-24

    Tumour metastasis in the lymphatics is a crucial step in the progression of breast cancer. The dynamics by which breast cancer cells (BCCs) travel in the lymphatics remains poorly understood. The goal of this work is to develop a model capable of predicting the shear stresses metastasising BCCs experience using numerical and experimental techniques. This paper models the fluidic transport of large particles ([Formula: see text] where [Formula: see text] is the particle diameter and W is the channel width) subjected to lymphatic flow conditions ([Formula: see text]), in a [Formula: see text] microchannel. The feasibility of using the dynamic fluid body interaction (DFBI) method to predict particle motion was assessed, and particle tracking experiments were performed. The experiments found that particle translational velocity decreased from the undisturbed fluid velocity with increasing particle size (5-14% velocity lag for [Formula: see text]). DFBI simulations were found to better predict particle behaviour than theoretical predictions; however, mesh restrictions in the near-wall region ([Formula: see text]) result in computationally expensive models. The simulations were in good agreement with the experiments ([Formula: see text] difference) across the channel ([Formula: see text]), with differences up to 25% in the near-wall region. Particles experience a range of shear stresses (0.002-0.12 Pa) and spatial shear gradients ([Formula: see text]) depending on their size and radial position. The predicted shear gradients are far in excess of values associated with BCC apoptosis ([Formula: see text]). Increasing our understanding of the shear stress magnitudes and gradients experienced by BCCs could be leveraged to elucidate whether a particular BCC size or location exists that encourages metastasis within the lymphatics.

  13. Laminar flow downregulates Notch activity to promote lymphatic sprouting.

    PubMed

    Choi, Dongwon; Park, Eunkyung; Jung, Eunson; Seong, Young Jin; Yoo, Jaehyuk; Lee, Esak; Hong, Mingu; Lee, Sunju; Ishida, Hiroaki; Burford, James; Peti-Peterdi, Janos; Adams, Ralf H; Srikanth, Sonal; Gwack, Yousang; Chen, Christopher S; Vogel, Hans J; Koh, Chester J; Wong, Alex K; Hong, Young-Kwon

    2017-04-03

    The major function of the lymphatic system is to drain interstitial fluid from tissue. Functional drainage causes increased fluid flow that triggers lymphatic expansion, which is conceptually similar to hypoxia-triggered angiogenesis. Here, we have identified a mechanotransduction pathway that translates laminar flow-induced shear stress to activation of lymphatic sprouting. While low-rate laminar flow commonly induces the classic shear stress responses in blood endothelial cells and lymphatic endothelial cells (LECs), only LECs display reduced Notch activity and increased sprouting capacity. In response to flow, the plasma membrane calcium channel ORAI1 mediates calcium influx in LECs and activates calmodulin to facilitate a physical interaction between Krüppel-like factor 2 (KLF2), the major regulator of shear responses, and PROX1, the master regulator of lymphatic development. The PROX1/KLF2 complex upregulates the expression of DTX1 and DTX3L. DTX1 and DTX3L, functioning as a heterodimeric Notch E3 ligase, concertedly downregulate NOTCH1 activity and enhance lymphatic sprouting. Notably, overexpression of the calcium reporter GCaMP3 unexpectedly inhibited lymphatic sprouting, presumably by disturbing calcium signaling. Endothelial-specific knockouts of Orai1 and Klf2 also markedly impaired lymphatic sprouting. Moreover, Dtx3l loss of function led to defective lymphatic sprouting, while Dtx3l gain of function rescued impaired sprouting in Orai1 KO embryos. Together, the data reveal a molecular mechanism underlying laminar flow-induced lymphatic sprouting.

  14. Genetic Dissection of Cardiac Remodeling in an Isoproterenol-Induced Heart Failure Mouse Model

    PubMed Central

    Wang, Jessica Jen-Chu; Rau, Christoph; Avetisyan, Rozeta; Ren, Shuxun; Romay, Milagros C.; Gong, Ke Wei; Wang, Yibin; Lusis, Aldons J.

    2016-01-01

    We aimed to understand the genetic control of cardiac remodeling using an isoproterenol-induced heart failure model in mice, which allowed control of confounding factors in an experimental setting. We characterized the changes in cardiac structure and function in response to chronic isoproterenol infusion using echocardiography in a panel of 104 inbred mouse strains. We showed that cardiac structure and function, whether under normal or stress conditions, has a strong genetic component, with heritability estimates of left ventricular mass between 61% and 81%. Association analyses of cardiac remodeling traits, corrected for population structure, body size and heart rate, revealed 17 genome-wide significant loci, including several loci containing previously implicated genes. Cardiac tissue gene expression profiling, expression quantitative trait loci, expression-phenotype correlation, and coding sequence variation analyses were performed to prioritize candidate genes and to generate hypotheses for downstream mechanistic studies. Using this approach, we have validated a novel gene, Myh14, as a negative regulator of ISO-induced left ventricular mass hypertrophy in an in vivo mouse model and demonstrated the up-regulation of immediate early gene Myc, fetal gene Nppb, and fibrosis gene Lgals3 in ISO-treated Myh14 deficient hearts compared to controls. PMID:27385019

  15. Visceral white fat remodelling contributes to intermittent hypoxia-induced atherogenesis.

    PubMed

    Poulain, Laureline; Thomas, Amandine; Rieusset, Jennifer; Casteilla, Louis; Levy, Patrick; Arnaud, Claire; Dematteis, Maurice

    2014-02-01

    Obstructive sleep apnoea is a highly prevalent disease characterised by repetitive upper airway collapse during sleep leading to intermittent hypoxia. Cardiometabolic complications of sleep apnoea have been mostly attributed to intermittent hypoxia. These consequences could be mediated through intermittent hypoxia-related alterations of the visceral white fat, as it is recognised for playing an important role in inflammation, atherogenesis and insulin resistance. Epididymal adipose tissue alterations were investigated in 20-week-old nonobese male apolipoprotein E-deficient mice exposed to intermittent hypoxia (inspiratory oxygen fraction 5-21%, 60-s cycle, 8 h · day(-1)) or air for 6 weeks. These adipose tissue alterations, as well as metabolic alterations and aortic atherosclerosis, were then assessed in lipectomised or sham-operated mice exposed to intermittent hypoxia or air for 6 weeks. Intermittent hypoxia induced morphological (shrunken adipocytes), functional (increased uncoupling protein-1 expression) and inflammatory (increased macrophage recruitment and secretion of interleukin-6 and tumour necrosis factor-α) remodelling of epididymal adipose tissue. Hypoxic mice presented more severe dyslipidaemia and atherosclerosis lesions and developed insulin resistance. Epididymal lipectomy attenuated both intermittent hypoxia-induced dyslipidaemia and atherogenesis, but did not improve insulin sensitivity. Our results confirmed that the dyslipidaemic and proatherogenic effects of intermittent hypoxia are partly mediated through morphological, functional and inflammatory remodelling of visceral white fat, regardless of obesity.

  16. Bone resorption and remodeling in murine collagenase-induced osteoarthritis after administration of glucosamine

    PubMed Central

    2011-01-01

    Introduction Glucosamine is an amino-monosaccharide and precursor of glycosaminoglycans, major components of joint cartilage. Glucosamine has been clinically introduced for the treatment of osteoarthritis but the data about its protective role in disease are insufficient. The goal of this study was to investigate the effect of long term administration of glucosamine on bone resorption and remodeling. Methods The effect of glucosamine on bone resorption and remodeling was studied in a model of collagenase-induced osteoarthritis (CIOA). The levels of macrophage-inflammatory protein (MIP)-1α, protein regulated upon activation, normal T-cell expressed, and secreted (RANTES), soluble receptor activator of nuclear factor kappa-B ligand (RANKL), tumor necrosis factor (TNF)-α, and interleukin (IL)-6, 4 and 10 in synovial fluid were measured by enzyme-linked immunosorbent assay (ELISA). Cell populations in synovial extracts and the expression of RANKL, of receptors for TNF-α (TNF-αR) and interferon γ (IFN-γR) on clusters of differentiation (CD) three positive T cells were analyzed by flow cytometry. Transforming growth factor (TGF)-β3, bone morphogenetic protein (BMP)-2, phosphorylated protein mothers against decapentaplegic homolog 2 (pSMAD-2), RANKL and Dickkopf-1 protein (DKK-1) positive staining in CIOA joints were determined by immunohistochemistry. Results The administration of glucosamine hydrochloride in CIOA mice inhibited loss of glycosaminoglycans (GAGs) and proteoglycans (PGs) in cartilage, bone erosion and osteophyte formation. It decreased the levels of soluble RANKL and IL-6 and induced IL-10 increase in the CIOA joint fluids. Glucosamine limited the number of CD11b positive Ly6G neutrophils and RANKL positive CD3 T cells in the joint extracts. It suppressed bone resorption via down-regulation of RANKL expression and affected bone remodeling in CIOA by decreasing BMP-2, TGF-β3 and pSMAD-2 expression and up-regulating DKK-1 joint levels. Conclusions

  17. Voltage dependent potassium channel remodeling in murine intestinal smooth muscle hypertrophy induced by partial obstruction.

    PubMed

    Liu, Dong-Hai; Huang, Xu; Guo, Xin; Meng, Xiang-Min; Wu, Yi-Song; Lu, Hong-Li; Zhang, Chun-Mei; Kim, Young-chul; Xu, Wen-Xie

    2014-01-01

    Partial obstruction of the small intestine causes obvious hypertrophy of smooth muscle cells and motility disorder in the bowel proximate to the obstruction. To identify electric remodeling of hypertrophic smooth muscles in partially obstructed murine small intestine, the patch-clamp and intracellular microelectrode recording methods were used to identify the possible electric remodeling and Western blot, immunofluorescence and immunoprecipitation were utilized to examine the channel protein expression and phosphorylation level changes in this research. After 14 days of obstruction, partial obstruction caused obvious smooth muscle hypertrophy in the proximally located intestine. The slow waves of intestinal smooth muscles in the dilated region were significantly suppressed, their amplitude and frequency were reduced, whilst the resting membrane potentials were depolarized compared with normal and sham animals. The current density of voltage dependent potassium channel (KV) was significantly decreased in the hypertrophic smooth muscle cells and the voltage sensitivity of KV activation was altered. The sensitivity of KV currents (IKV) to TEA, a nonselective potassium channel blocker, increased significantly, but the sensitivity of IKv to 4-AP, a KV blocker, stays the same. The protein levels of KV4.3 and KV2.2 were up-regulated in the hypertrophic smooth muscle cell membrane. The serine and threonine phosphorylation levels of KV4.3 and KV2.2 were significantly increased in the hypertrophic smooth muscle cells. Thus this study represents the first identification of KV channel remodeling in murine small intestinal smooth muscle hypertrophy induced by partial obstruction. The enhanced phosphorylations of KV4.3 and KV2.2 may be involved in this process.

  18. Flow-induced remodeling in resistance arteries from obese Zucker rats is associated with endothelial dysfunction.

    PubMed

    Bouvet, Céline; Belin de Chantemèle, Eric; Guihot, Anne-Laure; Vessières, Emilie; Bocquet, Arnaud; Dumont, Odile; Jardel, Alain; Loufrani, Laurent; Moreau, Pierre; Henrion, Daniel

    2007-07-01

    Chronic increases in blood flow increase arterial diameter and NO-dependent dilation in resistance arteries. Because endothelial dysfunction accompanies metabolic syndrome, we hypothesized that flow-mediated remodeling might be impaired in obese rat resistance arteries. Obese and lean Zucker rat mesenteric resistance arteries were exposed to chronic flow increases through arterial ligation in vivo: arteries exposed to high flow were compared with normal flow arteries. Diameter was measured in vitro in cannulated arteries using pressure arteriography. After 7 days, outward remodeling (diameter increased from 346+/-9 to 412+/-11 mum at 100 mm Hg) occurred in lean high-flow arteries. Endothelium-dependent tone was reduced in high-flow arteries from obese rats by contrast with lean animals. On the other hand, diameter enlargement occurred similarly in the 2 strains. The involvement of NO in endothelium-dependent dilation (evidenced by NO blockade) and endothelial NO synthase phosphorylation was smaller in obese than in lean rats. Superoxide anion and reduced nicotinamide-adenine dinucleotide phosphate oxidase subunit expression (p67phox and gp91phox) increased in obese rats and were higher in high-flow than in control arteries. Acute Tempol (a catalase mimetic), catalase plus superoxide dismutase, and l-arginine plus tetrahydrobiopterin restored endothelium-dependent dilation in obese rat normal and high-flow arteries to the level found in lean control arteries. Thus, flow-induced remodeling in obese resistance arteries was associated with a reduced endothelium-mediated dilation because of a decreased NO bioavailability and an excessive superoxide production. This dysfunction might have negative consequences in ischemic diseases in patients with obesity or metabolic syndrome.

  19. Allergen-induced airway remodeling in brown norway rats: structural and metabolic changes in glycosaminoglycans.

    PubMed

    Venkatesan, Narayanan; Siddiqui, Sana; Jo, Taisuke; Martin, James G; Ludwig, Mara S

    2012-01-01

    Increased proteoglycan (PG) deposition is a feature of airway remodeling in asthma. Glycosaminoglycans (GAGs) mediate many of the biological and mechanical properties of PGs by providing docking sites through their carbohydrate chains to bioactive ligands; therefore, it is imperative to define structural and metabolic changes of GAGs in asthma. Using a Brown Norway (BN) ovalbumin (OVA)-sensitized and -challenged rat model to induce airway remodeling, we found excessive deposition of chondroitin/dermatan (CS/DS)-, heparan (HS), and keratan (KS) sulfate GAGs in the airways and bronchoalveolar lavage cells of OVA-challenged rats. Disaccharide composition of CS/DS of OVA-challenged rats was significantly different compared with saline-treated (SAL) control rats, with increased levels of 0-, 6-, and 4-sulfated disaccharides. Increases in the amount and a change in the proportion of CS/DS versus HS GAGs were noted in OVA-challenged rats. The higher content and sulfation of CS/DS disaccharides was reflected by the increased expression of xylosyltransferase-I, β1,3-glucuronosyltransferase-I, chondroitin-4, and chondroitin-6 sulfotransferase genes and protein expression of xylosyltransferase-I and β1,3-glucuronosyltransferase-I in OVA-challenged rats. Genes encoding the core proteins of the CS/DS and KS-containing PGs, such as versican, biglycan, decorin, and lumican, were overexpressed in OVA-challenged rats. Our results suggest that GAG biosynthetic enzymes may be involved in the altered expression of GAGs in the airways and are potential targets for inhibiting excess PG-GAG deposition and the airway remodeling process in asthma.

  20. Cadherin-11 Overexpression Induces Extracellular Matrix Remodeling and Calcification in Mature Aortic Valves.

    PubMed

    Sung, Derek C; Bowen, Caitlin J; Vaidya, Kiran A; Zhou, Jingjing; Chapurin, Nikita; Recknagel, Andrew; Zhou, Bin; Chen, Jonathan; Kotlikoff, Michael; Butcher, Jonathan T

    2016-08-01

    Calcific aortic valve (AoV) disease is a significant clinical problem for which the regulatory mechanisms are poorly understood. Enhanced cell-cell adhesion is a common mechanism of cellular aggregation, but its role in calcific lesion formation is not known. Cadherin-11 (Cad-11) has been associated with lesion formation in vitro, but its function during adult valve homeostasis and pathogenesis is not known. This study aims to elucidate the specific functions of Cad-11 and its downstream targets, RhoA and Sox9, in extracellular matrix remodeling and AoV calcification. We conditionally overexpressed Cad-11 in murine heart valves using a novel double-transgenic Nfatc1(Cre);R26-Cad11(TglTg) mouse model. These mice developed hemodynamically significant aortic stenosis with prominent calcific lesions in the AoV leaflets. Cad-11 overexpression upregulated downstream targets, RhoA and Sox9, in the valve interstitial cells, causing calcification and extensive pathogenic extracellular matrix remodeling. AoV interstitial cells overexpressing Cad-11 in an osteogenic environment in vitro rapidly form calcific nodules analogous to in vivo lesions. Molecular analyses revealed upregulation of osteoblastic and myofibroblastic markers. Treatment with a Rho-associated protein kinase inhibitor attenuated nodule formation, further supporting that Cad-11-driven calcification acts through the small GTPase RhoA/Rho-associated protein kinase signaling pathway. This study identifies one of the underlying molecular mechanisms of heart valve calcification and demonstrates that overexpression of Cad-11 upregulates RhoA and Sox9 to induce calcification and extracellular matrix remodeling in adult AoV pathogenesis. The findings provide a potential molecular target for clinical treatment. © 2016 American Heart Association, Inc.

  1. Rat Heterotopic Heart Transplantation Model to Investigate Unloading-Induced Myocardial Remodeling

    PubMed Central

    Fu, Xuebin; Segiser, Adrian; Carrel, Thierry P.; Tevaearai Stahel, Hendrik T.; Most, Henriette

    2016-01-01

    Unloading of the failing left ventricle in order to achieve myocardial reverse remodeling and improvement of contractile function has been developed as a strategy with the increasing frequency of implantation of left ventricular assist devices in clinical practice. But, reverse remodeling remains an elusive target, with high variability and exact mechanisms still largely unclear. The small animal model of heterotopic heart transplantation (hHTX) in rodents has been widely implemented to study the effects of complete and partial unloading on cardiac failing and non-failing tissue to better understand the structural and molecular changes that underlie myocardial recovery. We herein review the current knowledge on the effects of volume unloading the left ventricle via different methods of hHTX in rats, differentiating between changes that contribute to functional recovery and adverse effects observed in unloaded myocardium. We focus on methodological aspects of heterotopic transplantation, which increase the correlation between the animal model and the setting of the failing unloaded human heart. Last, but not least, we describe the late use of sophisticated techniques to acquire data, such as small animal MRI and catheterization, as well as ways to assess unloaded hearts under “reloaded” conditions. While giving regard to certain limitations, heterotopic rat heart transplantation certainly represents the crucial model to mimic unloading-induced changes in the heart and as such the intricacies and challenges deserve highest consideration. Careful translational research will further improve our knowledge of the reverse remodeling process and how to potentiate its effect in order to achieve recovery of contractile function in more patients. PMID:27807535

  2. Adolescent nicotine-induced dendrite remodeling in the nucleus accumbens is rapid, persistent, and D1-dopamine receptor dependent.

    PubMed

    Ehlinger, D G; Bergstrom, H C; Burke, J C; Fernandez, G M; McDonald, C G; Smith, R F

    2016-01-01

    Chronic nicotine exposure during adolescence induces dendritic remodeling of medium spiny neurons (MSNs) in the nucleus accumbens (NAcc) shell. While nicotine-induced dendritic remodeling has frequently been described as persistent, the trajectory of dendrite remodeling is unknown. Specifically, no study to date has characterized the structural plasticity of dendrites in the NAcc immediately following chronic nicotine, leaving open the possibility that dendrite remodeling emerges gradually over time. Further, the neuropharmacological mechanisms through which nicotine induces dendrite remodeling are not well understood. To address these questions, rats were co-administered chronic nicotine (0.5 mg/kg) and the D1-dopamine receptor (D1DR) antagonist SCH-23390 (0.05 mg/kg) subcutaneously every other day during adolescence. Brains were then processed for Golgi-Cox staining either 1 day or 21 days following drug exposure and dendrites from MSNs in the NAcc shell digitally reconstructed in 3D. Spine density was also measured at both time points. Our morphometric results show (1) the formation of new dendritic branches and spines 1 day following nicotine exposure, (2) new dendritic branches, but not spine density, remains relatively stable for at least 21 days, (3) the co-administration of SCH-23390 completely blocked nicotine-induced dendritic remodeling of MSNs at both early and late time points, suggesting the formation of new dendritic branches in response to nicotine is D1DR-dependent, and (4) SCH-23390 failed to block nicotine-induced increases in spine density. Overall this study provides new insight into how nicotine influences the normal trajectory of adolescent brain development and demonstrates a persistent form of nicotine-induced neuroplasticity in the NAcc shell that develops rapidly and is D1DR dependent.

  3. Quantification of stretch-induced cytoskeletal remodeling in vascular endothelial cells by image processing.

    PubMed

    Yoshigi, Masaaki; Clark, Edward B; Yost, H Joseph

    2003-10-01

    Reorientation of the cell axis induced by cyclic stretching is an early response to mechanical forces in vitro. However, quantitative assay for this phenomenon has been difficult due to lack of robust methods. We hypothesized that cell orientation may be redefined by the orientation of actin fibers. We developed image processing methods to quantitate the orientation and density of actin fibers. A convolution filter using Sobel kernels was adapted to determine the orientation and density of actin fibers in human endothelial cells. Unidirectional stretching (10%, 0.5 Hz) was applied to induce cytoskeletal remodeling by varying the duration of stimulation (control, 0.5, 1, 2, 5, 10, and 20 h). Actin fibers were visualized by fluorescent phalloidin. The image processing method was compared with the manual method for reproducibility. Both confluent and subconfluent cells were tested to assess the efficacy of the methods. Cyclic stretch-induced dense and uninterrupted actin cabling formed across the cell body and, later, the actin fibers became aligned perpendicular to the stretch direction. The variance of actin fiber orientation became smaller after 2 h of stretch (F < 0.01). The actin fiber density index, a derived parameter related to the density of actin fibers, increased as early as 30 min of stretching (P < 0.05) and decreased after 10 h of stretching. Reproducibility of our method was extremely good. Applicability of the method was not compromised by cell density. Our method is reliable for quantifying cytoskeletal remodeling induced by mechanical force. Copyright 2003 Wiley-Liss, Inc.

  4. Aspirin enhances protective effect of fish oil against thrombosis and injury-induced vascular remodelling.

    PubMed

    Gong, Yanjun; Lin, Minghui; Piao, Lingjuan; Li, Xinzhi; Yang, Fei; Zhang, Jian; Xiao, Bing; Zhang, Qingli; Song, Wen-Liang; Yin, Huiyong; Zhu, Li; Funk, Colin D; Yu, Ying

    2015-12-01

    Although aspirin (acetylsalicylic acid) is commonly used to prevent ischaemic events in patients with coronary artery disease, many patients fail to respond to aspirin treatment. Dietary fish oil (FO), containing ω3 polyunsaturated fatty acids (PUFAs), has anti-inflammatory and cardio-protective properties, such as lowering cholesterol and modulating platelet activity. The objective of the present study was to investigate the potential additional effects of aspirin and FO on platelet activity and vascular response to injury. Femoral arterial remodelling was induced by wire injury in mice. Platelet aggregation, and photochemical- and ferric chloride-induced carotid artery thrombosis were employed to evaluate platelet function. FO treatment increased membrane ω3 PUFA incorporation, lowered plasma triglyceride and cholesterol levels, and reduced systolic BP in mice. FO or aspirin alone inhibited platelet aggregation; however, when combined, they exhibited synergistic suppression of platelet activity in mice, independent of COX-1 inhibition. FO alone, but not aspirin, attenuated arterial neointimal growth in response to injury. Strikingly, a combination of FO and aspirin synergistically inhibited injury-induced neointimal hyperplasia and reduced perivascular inflammatory reactions. Moreover, co-administration of FO and aspirin decreased the expression of pro-inflammatory cytokines and adhesion molecules in inflammatory cells. Consistently, a pro-resolution lipid mediator-Resolvin E1, was significantly elevated in plasma in FO/aspirin-treated mice. Co-administration of FO and low-dose aspirin may act synergistically to protect against thrombosis and injury-induced vascular remodelling in mice. Our results support further investigation of adjuvant FO supplementation for patients with stable coronary artery disease. © 2014 The British Pharmacological Society.

  5. Spleen and Lymphatic System

    MedlinePlus

    ... Get Weight Loss Surgery? A Week of Healthy Breakfasts Shyness Spleen and Lymphatic System KidsHealth > For Teens > Spleen and Lymphatic System Print A A A What's in this article? Why They're Important Basic Anatomy How It Works Things That Can ...

  6. Notch activation induces neurite remodeling and functional modifications in SH-SY5Y neuronal cells.

    PubMed

    Ferrari-Toninelli, Giulia; Bonini, Sara Anna; Uberti, Daniela; Napolitano, Francesco; Stante, Maria; Santoro, Federica; Minopoli, Giuseppina; Zambrano, Nicola; Russo, Tommaso; Memo, Maurizio

    2009-05-01

    Notch proteins are definitely recognized as key regulators of the neuronal fate during embryo development, but their function in the adult brain is still largely unknown. We have previously demonstrated that Notch pathway stimulation increases microtubules stability followed by the remodeling of neuronal morphology with neurite varicosities loss, thicker neuritis, and enlarged growth cones. Here we show that the neurite remodeling is a dynamic event, dependent on transcription and translation, and with functional implications. Exposure of differentiated human SH-SY5Y neuroblastoma cells to the Notch ligand Jagged1 induces varicosities loss all along the neurites, accompanied by the redistribution of presynaptic vesicles and the decrease in neurotransmitters release. As evaluated by time lapse digital imaging, dynamic changes in neurite morphology were rapidly reversible and dependent on the activation of the Notch signaling pathway. In fact, it was prevented by the inhibition of the proteolytic gamma-secretase enzyme or the transcription machinery, and was mimicked by the transfection of the intracellular domain of Notch. One hour after treatment with Jagged1, several genes were downregulated. Many of these genes encode proteins that are known to be involved in protein synthesis. These data suggest that in adult neurons, Notch pathway activates a transcriptional program that regulates the equilibrium between varicosities formation and varicosities loss in the neuronal presynaptic compartment involving the expression and redistribution of both structural and functional proteins.

  7. Diabetes induces stromal remodelling and increase in chondroitin sulphate proteoglycans of the rat ventral prostate.

    PubMed

    Ribeiro, Daniele Lisboa; Taboga, Sebastião Roberto; Góes, Rejane Maira

    2009-08-01

    Extracellular matrix (ECM) remodelling is an important process involved in prostate cancer progression. Alterations in ECM caused by diabetes in different tissues such as kidney is well described; however, it is poorly investigated in prostate. The aim of this study was to evaluate changes in ECM of rat prostate showing gland atrophy caused by diabetes and their implications in development of malignant lesions. Diabetes was induced in Wistar rats using alloxan (45 mg/kg bw). After 90 days of diabetes onset, animals were killed and ventral prostate was removed and prepared for light microscopy following immunoreaction for fibronectin, chondroitin sulphate and Picrossirius staining for collagen fibres. Proteoglycans (PG) were identified at transmission electron microscopy after fixation with Cuprolinic Blue. Diabetes led to a thickening of 25% in the acinar basement membrane accompanied by increase and disorganization of its proteoglycans (P1). Three additional populations of prostatic stromal PGs were identified: collagen fibril linked (P2) and interstitial (P3) and (P4) PGs. Diabetes increased P3 and mainly P4 which had higher dimension and accumulated around the smooth muscle cells. In addition, an increase in chondrotin sulphate (33%, mainly in sites where P4 were noted) and collagen (44%) was noted in diabetic rats, whereas fibronectin did not change. Atrophic changes observed in rat ventral prostate after diabetes are accompanied by stromal remodelation related to increase in collagen and chondroitin sulphate proteoglycans. Thus, diabetes can promote a stromal microenvironment rich in elements that could favour cell migration, proliferation and pathological process.

  8. Remodeling of biological tissue: Mechanically induced reorientation of a transversely isotropic chain network

    NASA Astrophysics Data System (ADS)

    Kuhl, Ellen; Garikipati, Krishna; Arruda, Ellen M.; Grosh, Karl

    2005-07-01

    A new class of micromechanically motivated chain network models for soft biological tissues is presented. On the microlevel, it is based on the statistics of long chain molecules. A wormlike chain model is applied to capture the behavior of the collagen microfibrils. On the macrolevel, the network of collagen chains is represented by a transversely isotropic eight chain unit cell introducing one characteristic material axis. Biomechanically induced remodeling is captured by allowing for a continuous reorientation of the predominant unit cell axis driven by a biomechanical stimulus. To this end, we adopt the gradual alignment of the unit cell axis with the direction of maximum principal strain. The evolution of the unit cell axis' orientation is governed by a first-order rate equation. For the temporal discretization of the remodeling rate equation, we suggest an exponential update scheme of Euler-Rodrigues type. For the spatial discretization, a finite element strategy is applied which introduces the current individual cell orientation as an internal variable on the integration point level. Selected model problems are analyzed to illustrate the basic features of the new model. Finally, the presented approach is applied to the biomechanically relevant boundary value problem of an in vitro engineered functional tendon construct.

  9. Inhalation exposure to ethylene induces eosinophilic rhinitis and nasal epithelial remodeling in Fischer 344 rats.

    PubMed

    Brandenberger, Christina; Hotchkiss, Jon A; Krieger, Shannon M; Pottenger, Lynn H; Harkema, Jack R

    2015-11-05

    This study investigated the time- and concentration-dependent effects of inhaled ethylene on eosinophilic rhinitis and nasal epithelial remodeling in Fisher 344 rats exposed to 0, 10, 50, 300, or 10,000 ppm ethylene, 6 h/day, 5 days/week for up to 4 weeks. Morphometric quantitation of eosinophilic inflammation and mucous cell metaplasia/hyperplasia (MCM) and nasal mucosal gene expression were evaluated at anatomic sites previously shown to undergo ethylene-induced epithelial remodeling. Serum levels of total IgE, IgG1 and IgG2a were measured to determine if ethylene exposure increased the expression of Th2-associated (IgE and IgG1) relative to Th1-associated (IgG2a) antibody isotypes. Rats exposed to 0 or 10,000 ppm for 1, 3, 5, 10, or 20 days were analyzed to assess the temporal pattern of ethylene-induced alterations in nasal epithelial cell proliferation, morphology and gene expression. Rats exposed to 0, 10, 50, 300, and 10,000 ppm ethylene for 20 days were analyzed to assess concentration-dependent effects on lesion development. Additional rats exposed 4 weeks to 0, 300, or 10,000 ppm ethylene were held for 13 weeks post-exposure to examine the persistence of ethylene-induced mucosal alterations. The data indicate that cell death and reparative cell proliferation were not a part of the pathogenesis of ethylene-induced nasal lesions. Enhanced gene expression of Th2 cytokines (e.g., IL-5, IL-13) and chitinase (YM1/2) in the nasal mucosa was much greater than that of Th1 cytokines (e.g., IFNγ) after ethylene exposure. A significant increase in MCM was measured after 5 days of exposure to 10,000 ppm ethylene and after 20 days of exposure 10 ppm ethylene. Ethylene-induced MCM was reversible after cessation of exposure. No increase in total serum IgE, IgG1 or IgG2a was measured in any ethylene-exposed group. These data do not support involvement of an immune-mediated allergic mechanism in the pathogenesis of ethylene-induced nasal lesions in rats. Repeated

  10. Exercise-Induced Skeletal Muscle Remodeling and Metabolic Adaptation: Redox Signaling and Role of Autophagy

    PubMed Central

    Giammarioli, Anna Maria; Chiandotto, Sergio; Spoletini, Ilaria

    2014-01-01

    Abstract Significance: Skeletal muscle is a highly plastic tissue. Exercise evokes signaling pathways that strongly modify myofiber metabolism and physiological and contractile properties of skeletal muscle. Regular physical activity is beneficial for health and is highly recommended for the prevention of several chronic conditions. In this review, we have focused our attention on the pathways that are known to mediate physical training-induced plasticity. Recent Advances: An important role for redox signaling has recently been proposed in exercise-mediated muscle remodeling and peroxisome proliferator-activated receptor γ (PPARγ) coactivator-1α (PGC-1α) activation. Still more currently, autophagy has also been found to be involved in metabolic adaptation to exercise. Critical Issues: Both redox signaling and autophagy are processes with ambivalent effects; they can be detrimental and beneficial, depending on their delicate balance. As such, understanding their role in the chain of events induced by exercise and leading to skeletal muscle remodeling is a very complicated matter. Moreover, the study of the signaling induced by exercise is made even more difficult by the fact that exercise can be performed with several different modalities, with this having different repercussions on adaptation. Future Directions: Unraveling the complexity of the molecular signaling triggered by exercise on skeletal muscle is crucial in order to define the therapeutic potentiality of physical training and to identify new pharmacological compounds that are able to reproduce some beneficial effects of exercise. In evaluating the effect of new “exercise mimetics,” it will also be necessary to take into account the involvement of reactive oxygen species, reactive nitrogen species, and autophagy and their controversial effects. Antioxid. Redox Signal. 21, 154–176. PMID:24450966

  11. MicroRNA Expression Signature Is Altered in the Cardiac Remodeling Induced by High Fat Diets.

    PubMed

    Guedes, Elaine Castilho; França, Gustavo Starvaggi; Lino, Caroline Antunes; Koyama, Fernanda Christtanini; Moreira, Luana do Nascimento; Alexandre, Juliana Gomes; Barreto-Chaves, Maria Luiza M; Galante, Pedro Alexandre Favoretto; Diniz, Gabriela Placoná

    2016-08-01

    Recent studies have revealed the involvement of microRNAs (miRNAs) in the control of cardiac hypertrophy and myocardial function. In addition, several reports have demonstrated that high fat (HF) diet induces cardiac hypertrophy and remodeling. In the current study, we investigated the effect of diets containing different percentages of fat on the cardiac miRNA expression signature. To address this question, male C57Bl/6 mice were fed with a low fat (LF) diet or two HF diets, containing 45 kcal% fat (HF45%) and 60 kcal% fat (HF60%) for 10 and 20 weeks. HF60% diet promoted an increase on body weight, fasting glycemia, insulin, leptin, total cholesterol, triglycerides, and induced glucose intolerance. HF feeding promoted cardiac remodeling, as evidenced by increased cardiomyocyte transverse diameter and interstitial fibrosis. RNA sequencing analysis demonstrated that HF feeding induced distinct miRNA expression patterns in the heart. HF45% diet for 10 and 20 weeks changed the abundance of 64 and 26 miRNAs in the heart, respectively. On the other hand, HF60% diet for 10 and 20 weeks altered the abundance of 27 and 88 miRNAs in the heart, respectively. Bioinformatics analysis indicated that insulin signaling pathway was overrepresented in response to HF diet. An inverse correlation was observed between cardiac levels of GLUT4 and miRNA-29c. Similarly, we found an inverse correlation between expression of GSK3β and the expression of miRNA-21a-3p, miRNA-29c-3p, miRNA-144-3p, and miRNA-195a-3p. In addition, miRNA-1 overexpression prevented cardiomyocyte hypertrophy. Taken together, our results revealed differentially expressed miRNA signatures in the heart in response to different HF diets. J. Cell. Physiol. 231: 1771-1783, 2016. © 2015 Wiley Periodicals, Inc.

  12. Effect of Lysyl Oxidase Inhibition on Angiotensin II-Induced Arterial Hypertension, Remodeling, and Stiffness

    PubMed Central

    Eberson, Lance S.; Sanchez, Pablo A.; Majeed, Beenish A.; Tawinwung, Supannikar; Secomb, Timothy W.; Larson, Douglas F.

    2015-01-01

    It is well accepted that angiotensin II (Ang II) induces altered vascular stiffness through responses including both structural and material remodeling. Concurrent with remodeling is the induction of the enzyme lysyl oxidase (LOX) through which ECM proteins are cross-linked. The study objective was to determine the effect of LOX mediated cross-linking on vascular mechanical properties. Three-month old mice were chronically treated with Ang II with or without the LOX blocker, β -aminopropionitrile (BAPN), for 14 days. Pulse wave velocity (PWV) from Doppler measurements of the aortic flow wave was used to quantify in vivo vascular stiffness in terms of an effective Young’s modulus. The increase in effective Young’s modulus with Ang II administration was abolished with the addition of BAPN, suggesting that the material properties are a major controlling element in vascular stiffness. BAPN inhibited the Ang II induced collagen cross-link formation by 2-fold and PWV by 44% (P<0.05). Consistent with this observation, morphometric analysis showed that BAPN did not affect the Ang II mediated increase in medial thickness but significantly reduced the adventitial thickness. Since the hypertensive state contributes to the measured in vivo PWV stiffness, we removed the Ang II infusion pumps on Day 14 and achieved normal arterial blood pressures. With pump removal we observed a decrease of the PWV in the Ang II group to 25% above that of the control values (P=0.002), with a complete return to control values in the Ang II plus BAPN group. In conclusion, we have shown that the increase in vascular stiffness with 14 day Ang II administration results from a combination of hypertension-induced wall strain, adventitial wall thickening and Ang II mediated LOX ECM cross-linking, which is a major material source of vascular stiffening, and that the increased PWV was significantly inhibited with co-administration of BAPN. PMID:25875748

  13. Effects of fenofibrate on cardiac remodeling in aldosterone-induced hypertension.

    PubMed

    Lebrasseur, Nathan K; Duhaney, Toni-Ann S; De Silva, Deepa S; Cui, Lei; Ip, Peter C; Joseph, Lija; Sam, Flora

    2007-09-01

    Hypertension and cardiac remodeling are associated with myocardial fibrosis, left ventricular (LV) hypertrophy, and diastolic heart failure. Fenofibrate suppresses aldosterone-mediated increases in myocyte matrix metalloproteinase activity and extracellular signal-regulated kinase phosphorylation. It is unknown whether the peroxisome proliferator-activated receptor-alpha agonist, fenofibrate, improves cardiac remodeling in a model of aldosterone-induced hypertension and LV hypertrophy. Twelve-week-old uninephrectomized FVB mice received 1% NaCl drinking water. Miniosmotic pumps delivered saline or aldosterone for 4 weeks. Mice were either untreated (n=14) or treated with fenofibrate 100 mg/kg per day (n=12) for 1 week before and 4 weeks after surgery. Aldosterone increased systolic blood pressure in untreated mice versus saline-untreated mice (134+/-3 versus 91+/-3 mm Hg; P<0.01). This was unaffected by fenofibrate (131+/-3 mm Hg). Aldosterone increased LV end-diastolic and end-systolic dimensions, which were significantly attenuated by fenofibrate (3.8+/-0.1 versus 3.5+/-0.1 mm, and 1.5+/-0.1 versus 1.15+/-0.1 mm, respectively). Fenofibrate also decreased aldosterone-induced LV hypertrophy (LV weight/body weight, 4.1+/-0.2 versus 4.6+/-0.1 mg/g) and improved percent LV fractional shortening (67+/-7% versus 60+/-2%). Additionally, fenofibrate ameliorated the increased matrix metalloproteinase-2/tissue inhibitors of metalloproteinase-2 ratio and fibrosis seen in aldosterone-untreated hearts (P<0.05 for both). Furthermore, in aldosterone-untreated hearts, fenofibrate decreased transforming growth factor-beta, collagen type III (P<0.05 for both), and collagen type I (P<0.01) protein expression. Conversely fenofibrate increased peroxisome proliferator-activated receptor-alpha, peroxisome proliferator-activated receptor-gamma coactivator-1alpha expression, and acetyl coenzyme A carboxylase phosphorylation (P<0.05 for all) in aldosterone-infused hearts; uncoupling

  14. Endothelial nitric oxide synthase mediates lymphangiogenesis and lymphatic metastasis

    PubMed Central

    Lahdenranta, Johanna; Hagendoorn, Jeroen; Padera, Timothy P.; Hoshida, Tohru; Nelson, Gregory; Kashiwagi, Satoshi; Jain, Rakesh K.; Fukumura, Dai

    2009-01-01

    Lymphatic metastasis is a critical determinant of cancer prognosis. Recently, several lymphangiogenic molecules such as vafscular endothelial growth factor (VEGF)-C and -D were identified. However, the mechanistic understanding of lymphatic metastasis is still in infancy. Nitric oxide (NO) plays a crucial role in regulating blood vessel growth and function as well as lymphatic vessel function. NOS expression correlates with lymphatic metastasis. However, causal relationship between NOS and lymphatic metastasis has not been documented. To this end, we first show that both VEGF receptor-2 and -3 stimulation activate eNOS in lymphatic endothelial cells and that NO donors induce proliferation and/or survival of cultured lymphatic endothelial cells in a dose dependent manner. We find that an NOS inhibitor L-NMMA blocked regeneration of lymphatic vessels. Using intravital microscopy that allows us to visualize the steps of lymphatic metastasis, we show that genetic deletion of eNOS as well as NOS blockade attenuates peritumor lymphatic hyperplasia of VEGF-C-overexpressing T241 fibrosarcomas and decreases the delivery of metastatic tumor cells to the draining lymph nodes. Genetic deletion of eNOS in the host also leads to a decrease in T241 tumor cell dissemination to the lymph nodes and macroscopic lymph node metastasis of B16F10 melanoma. These findings indicate that eNOS mediates VEGF-C induced lymphangiogenesis and, consequently, plays a critical role in lymphatic metastasis. Our findings explain the correlation between NOS and lymphatic metastasis seen in a number of human tumors and open the door for potential therapies exploiting NO signaling to treat diseases of the lymphatic system. PMID:19318557

  15. Tissue Engineering of Dermal Blood and Lymphatic Microvascular Networks

    DTIC Science & Technology

    2014-03-06

    SECURITY CLASSIFICATION OF: This proposal focused on establishing the conditions necessary to induce lymphatic endothelial cell (EC) tube...morphogenesis in 3D collagen matrices with the long-term goal of establishing separate networks of lymphatic tubes and co-existing, but not interconnecting...networks of blood EC-lined tubes. In addition, we hoped that pericytes, which support blood EC tube networks, but not lymphatic vessel networks, would

  16. Intermittent Hypoxia-Induced Cardiovascular Remodeling Is Reversed by Normoxia in a Mouse Model of Sleep Apnea.

    PubMed

    Castro-Grattoni, Anabel L; Alvarez-Buvé, Roger; Torres, Marta; Farré, Ramon; Montserrat, Josep M; Dalmases, Mireia; Almendros, Isaac; Barbé, Ferran; Sánchez-de-la-Torre, Manuel

    2016-06-01

    Intermittent hypoxia (IH) is the principal injurious factor involved in the cardiovascular morbidity and mortality associated with OSA. The gold standard for treatment is CPAP, which eliminates IH and appears to reduce cardiovascular risk. There is no experimental evidence on the reversibility of cardiovascular remodeling after IH withdrawal. The objective of the present study is to assess the reversibility of early cardiovascular structural remodeling induced by IH after resumption of normoxic breathing in a novel recovery animal model mimicking OSA treatment. We investigated cardiovascular remodeling in C57BL/6 mice exposed to IH for 6 weeks vs the normoxia group and its spontaneous recovery after 6 subsequent weeks under normoxia. Aortic expansive remodeling was induced by IH, with intima-media thickening and without lumen perimeter changes. Elastic fiber network disorganization, fragmentation, and estrangement between the end points of disrupted fibers were increased by IH. Extracellular matrix turnover was altered, as visualized by collagen and mucoid interlaminar accumulation. Furthermore, left ventricular perivascular fibrosis was increased by IH, whereas cardiomyocytes size was unaffected. These cardiovascular remodeling events induced by IH were normalized after recovery in normoxia, mimicking CPAP treatment. The early structural cardiovascular remodeling induced by IH was normalized after IH removal, revealing a novel recovery model for studying the effects of OSA treatment. Our findings suggest the clinical relevance of early detection and effective treatment of OSA in patients to prevent the natural course of cardiovascular diseases. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  17. Particle-induced osteolysis is not accompanied by systemic remodeling but is reflected by systemic bone biomarkers.

    PubMed

    Ross, R D; Virdi, A S; Liu, S; Sena, K; Sumner, D R

    2014-07-01

    Particle-induced osteolysis is caused by an imbalance in bone resorption and formation, often leading to loss of implant fixation. Bone remodeling biomarkers may be useful for identification of osteolysis and studying pathogenesis, but interpretation of biomarker data could be confounded if local osteolysis engenders systemic bone remodeling. Our goal was to determine if remote bone remodeling contributes to biomarker levels. Serum concentrations of eight biomarkers and bone remodeling rates at local (femur), contiguous (tibia), and remote (humerus and lumbar vertebra) sites were evaluated in a rat model of particle-induced osteolysis. Serum CTX-1, cathepsin K, PINP, and OPG were elevated and osteocalcin was suppressed in the osteolytic group, but RANKL, TRAP 5b, and sclerostin were not affected at the termination of the study at 12 weeks. The one marker tested longitudinally (CTX-1) was elevated by 3 weeks. We found increased bone resorption and decreased bone formation locally, subtle differences in contiguous sites, but no differences remotely at 12 weeks. Thus, the skeletal response to local particle challenge was not systemic, implying that the observed differences in serum biomarker levels reflect differences in local remodeling. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  18. Hypoxia-Induced Pulmonary Vascular Remodeling Requires Recruitment of Circulating Mesenchymal Precursors of a Monocyte/Macrophage Lineage

    PubMed Central

    Frid, Maria G.; Brunetti, Jacqueline A.; Burke, Danielle L.; Carpenter, Todd C.; Davie, Neil J.; Reeves, John T.; Roedersheimer, Mark T.; van Rooijen, Nico; Stenmark, Kurt R.

    2006-01-01

    Vascular remodeling in chronic hypoxic pulmonary hypertension includes marked fibroproliferative changes in the pulmonary artery (PA) adventitia. Although resident PA fibroblasts have long been considered the primary contributors to these processes, we tested the hypothesis that hypoxia-induced pulmonary vascular remodeling requires recruitment of circulating mesenchymal precursors of a monocyte/macrophage lineage, termed fibrocytes. Using two neonatal animal models (rats and calves) of chronic hypoxic pulmonary hypertension, we demonstrated a dramatic perivascular accumulation of mononuclear cells of a monocyte/macrophage lineage (expressing CD45, CD11b, CD14, CD68, ED1, ED2). Many of these cells produced type I collagen, expressed α-smooth muscle actin, and proliferated, thus exhibiting mesenchymal cell characteristics attributed to fibrocytes. The blood-borne origin of these cells was confirmed in experiments wherein circulating monocytes/macrophages of chronically hypoxic rats were in vivo-labeled with DiI fluorochrome via liposome delivery and subsequently identified in the remodeled pulmonary, but not systemic, arterial adventitia. The DiI-labeled cells that appeared in the vessel wall expressed monocyte/macrophage markers and procollagen. Selective depletion of this monocytic cell population, using either clodronate-liposomes or gadolinium chloride, prevented pulmonary adventitial remodeling (ie, production of collagen, fibronectin, and tenascin-C and accumulation of myofibroblasts). We conclude that circulating mesenchymal precursors of a monocyte/macrophage lineage, including fibrocytes, are essential contributors to hypoxia-induced pulmonary vascular remodeling. PMID:16436679

  19. The muscle contraction mode determines lymphangiogenesis differentially in rat skeletal and cardiac muscles by modifying local lymphatic extracellular matrix microenvironments.

    PubMed

    Greiwe, L; Vinck, M; Suhr, F

    2016-05-01

    Lymphatic vessels are of special importance for tissue homeostasis, and increases of their density may foster tissue regeneration. Exercise could be a relevant tool to increase lymphatic vessel density (LVD); however, a significant lack of knowledge remains to understand lymphangiogenesis in skeletal muscles upon training. Interestingly, training-induced lymphangiogenesis has never been studied in the heart. We studied lymphangiogenesis and LVD upon chronic concentric and chronic eccentric muscle contractions in both rat skeletal (Mm. Edl and Sol) and cardiac muscles. We found that LVD decreased in both skeletal muscles specifically upon eccentric training, while this contraction increased LVD in cardiac tissue. These observations were supported by opposing local remodelling of lymphatic vessel-specific extracellular matrix components in skeletal and cardiac muscles and protein levels of lymphatic markers (Lyve-1, Pdpn, Vegf-C/D). Confocal microscopy further revealed transformations of lymphatic vessels into vessels expressing both blood (Cav-1) and lymphatic (Vegfr-3) markers upon eccentric training specifically in skeletal muscles. In addition and phenotype supportive, we found increased inflammation (NF-κB/p65, Il-1β, Ifn-γ, Tnf-α and MPO(+) cells) in eccentrically stressed skeletal, but decreased levels in cardiac muscles. Our data provide novel mechanistic insights into lymphangiogenic processes in skeletal and cardiac muscles upon chronic muscle contraction modes and demonstrate that both tissues adapt in opposing manners specifically to eccentric training. These data are highly relevant for clinical applications, because eccentric training serves as a sufficient strategy to increase LVD and to decrease inflammation in cardiac tissue, for example in order to reduce tissue abortion in transplantation settings. © 2015 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

  20. Titin, a Central Mediator for Hypertrophic Signaling, Exercise-Induced Mechanosignaling and Skeletal Muscle Remodeling

    PubMed Central

    Krüger, Martina; Kötter, Sebastian

    2016-01-01

    Titin is a giant scaffold protein with multiple functions in striated muscle physiology. Due to the elastic I-band domains and the filament-like integration in the half-sarcomere titin is an important factor for sarcomere assembly and serves as an adaptable molecular spring that determines myofilament distensibility. Protein-interactions e.g., with muscle ankyrin repeat proteins or muscle LIM-protein link titin to hypertrophic signaling and via p62 and Muscle Ring Finger proteins to mechanisms that control protein quality control. This review summarizes our current knowledge on titin as a central node for exercise-induced mechanosignaling and remodeling and further highlights the pathophysiological implications. PMID:26973541

  1. Autophagy inhibition and mitochondrial remodeling join forces to amplify apoptosis in activation-induced cell death.

    PubMed

    Mauro, Corrado; Silvia, Campello

    2016-12-01

    Mitochondrial structural and functional changes and the autophagy pathway crosstalk under several stress conditions. However, their interplay under physiological cell death stimulation has been unclear. In our recent report, we show that during activation-induced cell death (AICD), the T-cell receptor (TCR)-dependent pathway that controls immune tolerance, autophagy is inhibited at an early stage. Further, we found that this inhibition is coupled with mitochondria fragmentation and cristae remodeling to unleash the apoptotic program. Last, we dissected the role of macroautophagy/autophagy versus mitophagy in the context of this physiological cell death, and bulk autophagy turned out to be able to remove dysfunctional and depolarized mitochondria. Our data suggest new possible approaches to modulate the immune function in the context of autoimmunity or immunotherapy.

  2. AID-induced remodeling of immunoglobulin genes and B cell fate.

    PubMed

    Laffleur, Brice; Denis-Lagache, Nicolas; Péron, Sophie; Sirac, Christophe; Moreau, Jeanne; Cogné, Michel

    2014-03-15

    Survival and phenotype of normal and malignant B lymphocytes are critically dependent on constitutive signals by the B cell receptor (BCR) for antigen. In addition, either antigen ligation of the BCR or various mitogenic stimuli result in B cell activation and induction of activation-induced deaminase (AID). AID activity can in turn mediate somatic hypermutation (SHM) of immunoglobulin (Ig) V regions and also deeply remodel the Ig heavy chain locus through class switch recombination (CSR) or locus suicide recombination (LSR). In addition to changes linked to affinity for antigen, modifying the class/isotype (i.e. the structure and function) of the BCR or suddenly deleting BCR expression also modulates the fate of antigen-experienced B cells.

  3. Back to the future: transgenerational transmission of xenobiotic-induced epigenetic remodeling.

    PubMed

    Jiménez-Chillarón, Josep C; Nijland, Mark J; Ascensão, António A; Sardão, Vilma A; Magalhães, José; Hitchler, Michael J; Domann, Frederick E; Oliveira, Paulo J

    2015-01-01

    Epigenetics, or regulation of gene expression independent of DNA sequence, is the missing link between genotype and phenotype. Epigenetic memory, mediated by histone and DNA modifications, is controlled by a set of specialized enzymes, metabolite availability, and signaling pathways. A mostly unstudied subject is how sub-toxic exposure to several xenobiotics during specific developmental stages can alter the epigenome and contribute to the development of disease phenotypes later in life. Furthermore, it has been shown that exposure to low-dose xenobiotics can also result in further epigenetic remodeling in the germ line and contribute to increase disease risk in the next generation (multigenerational and transgenerational effects). We here offer a perspective on current but still incomplete knowledge of xenobiotic-induced epigenetic alterations, and their possible transgenerational transmission. We also propose several molecular mechanisms by which the epigenetic landscape may be altered by environmental xenobiotics and hypothesize how diet and physical activity may counteract epigenetic alterations.

  4. Back to the future: transgenerational transmission of xenobiotic-induced epigenetic remodeling

    PubMed Central

    Jiménez-Chillarón, Josep C; Nijland, Mark J; Ascensão, António A; Sardão, Vilma A; Magalhães, José; Hitchler, Michael J; Domann, Frederick E; Oliveira, Paulo J

    2015-01-01

    Epigenetics, or regulation of gene expression independent of DNA sequence, is the missing link between genotype and phenotype. Epigenetic memory, mediated by histone and DNA modifications, is controlled by a set of specialized enzymes, metabolite availability, and signaling pathways. A mostly unstudied subject is how sub-toxic exposure to several xenobiotics during specific developmental stages can alter the epigenome and contribute to the development of disease phenotypes later in life. Furthermore, it has been shown that exposure to low-dose xenobiotics can also result in further epigenetic remodeling in the germ line and contribute to increase disease risk in the next generation (multigenerational and transgenerational effects). We here offer a perspective on current but still incomplete knowledge of xenobiotic-induced epigenetic alterations, and their possible transgenerational transmission. We also propose several molecular mechanisms by which the epigenetic landscape may be altered by environmental xenobiotics and hypothesize how diet and physical activity may counteract epigenetic alterations. PMID:25774863

  5. The orphan nuclear receptor Nur77 inhibits low shear stress-induced carotid artery remodeling in mice.

    PubMed

    Yu, Ying; Cai, Zhaohua; Cui, Mingli; Nie, Peng; Sun, Zhe; Sun, Shiqun; Chu, Shichun; Wang, Xiaolei; Hu, Liuhua; Yi, Jing; Shen, Linghong; He, Ben

    2015-12-01

    Shear stress, particularly low and oscillatory shear stress, plays a critical pathophysiological role in vascular remodeling-related cardiovascular diseases. Growing evidence suggests that the orphan nuclear receptor Nur77 [also known as TR3 or nuclear receptor subfamily 4, group A, member 1 (NR4A1)] is expressed in diseased human vascular tissue and plays an important role in vascular physiology and pathology. In the present study, we used a mouse model of flow-dependent remodeling by partial ligation of the left common carotid artery (LCCA) to define the exact role of Nur77 in vascular remodeling induced by low shear stress. Following vascular remodeling, Nur77 was highly expressed in neointimal vascular smooth muscle cells (VSMCs) in the ligated carotid arteries. The reactive oxygen species (ROS) levels were elevated in the remodeled arteries in vivo and in primary rat VSMCs in vitro following stimulation with platelet-derived growth factor (PDGF). Further in vitro experiments revealed that Nur77 expression was rapidly increased in the VSMCs following stimulation with PDGF and H2O2, whereas treatment with N-acetyl cysteine (NAC, a ROS scavenger) reversed the increase in the protein level of Nur77 induced by H2O2. Moreover, Nur77 overexpression markedly inhibited the proliferation and migration of VSMCs, induced by PDGF. Finally, to determine the in vivo role of Nur77 in low shear stress-induced vascular remodeling, wild-type (WT) and Nur77-deficient mice were subjected to partial ligation of the LCCA. Four weeks following surgery, in the LCCAs of the Nur77‑deficient mice, a significant increase in the intima-media area and carotid intima-media thickness was noted, as well as more severe elastin disruption and collagen deposition compared to the WT mice. Immunofluorescence staining revealed an increase in VSMC proliferation [determined by the expression of proliferating cell nuclear antigen (PCNA)] and matrix metalloproteinase 9 (MMP-9) production in the Nur77

  6. Imidapril inhibits right ventricular remodeling induced by low ambient temperature in broiler chickens.

    PubMed

    Hao, Xue-Qin; Zhang, Shou-Yan; Cheng, Xiang-Chao; Li, Meng; Sun, Tong-Wen; Zhang, Ji-Liang; Guo, Wen; Li, Li

    2013-06-01

    This study explored the effect of imidapril on the right ventricular remodeling induced by low ambient temperature in broiler chickens. Twenty-four broiler chickens were randomly divided into 3 groups (n = 8), including the control group, low temperature group, and imidapril group. Chickens in the control group were raised at normal temperature, whereas chickens in the low temperature group and imidapril group were exposed to low ambient temperature (12 to 18°C) from 14 d of age until 45 d of age. At the same time, chickens in the imidapril group were gavaged with imidapril at 3 mg/kg once daily for 30 d. The thickness of the right ventricular wall was observed with echocardiography. The BW and wet lung weight as well as weight of right and left ventricles and ventricular septum were measured. Both wet lung weight index and right ventricular hypertrophy index were calculated. Pulmonary arterial systolic pressure was assessed according to echocardiography. The expression of ACE and ACE2 mRNA in the right ventricular myocardial tissue was quantified by real-time PCR. Proliferating cell nuclear antigen-positive cells were detected by immunohistostaining. The concentration of angiotensin (Ang) II and Ang (1-7) in the right ventricular myocardial tissue was measured with ELISA. The results showed that right ventricular hypertrophy index, wet lung weight index, pulmonary arterial systolic pressure, expression of ACE mRNA in the right ventricular tissue, Ang II concentration, and the thickness of the right ventricular wall in the low temperature group increased significantly compared with those in the control group and imidapril group. The ACE2 mRNA expression increased 36%, whereas Ang (1-7) concentration decreased significantly in the low temperature group compared with that in the control group and imidapril group. In conclusion, imidapril inhibits right ventricular remodeling induced by low ambient temperature in broiler chickens.

  7. Drinking citrus fruit juice inhibits vascular remodeling in cuff-induced vascular injury mouse model.

    PubMed

    Ohnishi, Arika; Asayama, Rie; Mogi, Masaki; Nakaoka, Hirotomo; Kan-No, Harumi; Tsukuda, Kana; Chisaka, Toshiyuki; Wang, Xiao-Li; Bai, Hui-Yu; Shan, Bao-Shuai; Kukida, Masayoshi; Iwanami, Jun; Horiuchi, Masatsugu

    2015-01-01

    Citrus fruits are thought to have inhibitory effects on oxidative stress, thereby attenuating the onset and progression of cancer and cardiovascular disease; however, there are few reports assessing their effect on vascular remodeling. Here, we investigated the effect of drinking the juice of two different citrus fruits on vascular neointima formation using a cuff-induced vascular injury mouse model. Male C57BL6 mice were divided into five groups as follows: 1) Control (water) (C), 2) 10% Citrus unshiu (CU) juice (CU10), 3) 40% CU juice (CU40), 4) 10% Citrus iyo (CI) juice (CI10), and 5) 40% CI juice (CI40). After drinking them for 2 weeks from 8 weeks of age, cuff injury was induced by polyethylene cuff placement around the femoral artery. Neointima formation was significantly attenuated in CU40, CI10 and CI40 compared with C; however, no remarkable preventive effect was observed in CU10. The increases in levels of various inflammatory markers including cytokines such as monocyte chemotactic protein-1, interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α in response to vascular injury did not differ significantly between C, CU10 and CI10. The increases in cell proliferation and superoxide anion production were markedly attenuated in CI10, but not in CU10 compared with C. The increase in phosphorylated ERK expression was markedly attenuated both in CU10 and CI10 without significant difference between CU10 and CI10. Accumulation of immune cells did not differ between CU10 and CI10. These results indicate that drinking citrus fruit juice attenuates vascular remodeling partly via a reduction of oxidative stress. Interestingly, the preventive efficacy on neointima formation was stronger in CI than in CU at least in part due to more prominent inhibitory effects on oxidative stress by CI.

  8. Drinking Citrus Fruit Juice Inhibits Vascular Remodeling in Cuff-Induced Vascular Injury Mouse Model

    PubMed Central

    Ohnishi, Arika; Asayama, Rie; Mogi, Masaki; Nakaoka, Hirotomo; Kan-no, Harumi; Tsukuda, Kana; Chisaka, Toshiyuki; Wang, Xiao-Li; Bai, Hui-Yu; Shan, Bao-Shuai; Kukida, Masayoshi; Iwanami, Jun; Horiuchi, Masatsugu

    2015-01-01

    Citrus fruits are thought to have inhibitory effects on oxidative stress, thereby attenuating the onset and progression of cancer and cardiovascular disease; however, there are few reports assessing their effect on vascular remodeling. Here, we investigated the effect of drinking the juice of two different citrus fruits on vascular neointima formation using a cuff-induced vascular injury mouse model. Male C57BL6 mice were divided into five groups as follows: 1) Control (water) (C), 2) 10% Citrus unshiu (CU) juice (CU10), 3) 40% CU juice (CU40), 4) 10% Citrus iyo (CI) juice (CI10), and 5) 40% CI juice (CI40). After drinking them for 2 weeks from 8 weeks of age, cuff injury was induced by polyethylene cuff placement around the femoral artery. Neointima formation was significantly attenuated in CU40, CI10 and CI40 compared with C; however, no remarkable preventive effect was observed in CU10. The increases in levels of various inflammatory markers including cytokines such as monocyte chemotactic protein-1, interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α in response to vascular injury did not differ significantly between C, CU10 and CI10. The increases in cell proliferation and superoxide anion production were markedly attenuated in CI10, but not in CU10 compared with C. The increase in phosphorylated ERK expression was markedly attenuated both in CU10 and CI10 without significant difference between CU10 and CI10. Accumulation of immune cells did not differ between CU10 and CI10. These results indicate that drinking citrus fruit juice attenuates vascular remodeling partly via a reduction of oxidative stress. Interestingly, the preventive efficacy on neointima formation was stronger in CI than in CU at least in part due to more prominent inhibitory effects on oxidative stress by CI. PMID:25692290

  9. Stress-Induced Sensitization To Cocaine: Actin Cytoskeleton Remodeling Within Mesocorticolimbic Nuclei

    PubMed Central

    Esparza, Maria A; Bollati, Flavia; Garcia-Keller, Constanza; Virgolini, Miriam B; Lopez, Lidia M; Brusco, Alicia; Shen, Hao-Wei; Kalivas, Peter W; Cancela, Liliana M

    2015-01-01

    This study investigated the consequence of repeated stress on actin cytoskeleton remodeling in the nucleus accumbens (NAc) and prefrontal cortex (Pfc), and the involvement of this remodeling in the expression of stress-induced motor cross-sensitization with cocaine. Wistar rats were restrained daily (2 hours) for 7 days and, three weeks later, their NAc and Pfc were dissected 45 min after acute saline or cocaine (30 mg/kg i.p.). F-actin, actin-binding proteins (ABP) and GluR1 were quantified by western blotting, and dendritic spines and PSD size measured by electron microscopy. In the NAc from the stress plus cocaine group we observed a decrease in the phosphorylation of two ABPs, cofilin and cortactin, and an increase in the PSD size and the surface expression of GluR1, consistent with a more highly branched actin cytoskeleton. The Pfc also showed evidence of increased actin polymerization after stress as an increase was observed in Arp2, and in the number of spines. Inhibiting actin cycling and polymerization with latrunculin A into the NAc, but not the Pfc, inhibited the expression of cross-sensitization to cocaine (15 mg/kg i.p.) and restored the expression of GluR1 to control levels. This study shows that a history of repeated stress alters the ability of a subsequent cocaine injection to modulate dendritic spine morphology, actin dynamics and GluR1 expression in the NAc. Furthermore, by regulating GluR1 expression in the NAc, elevated actin cycling contributes to the expression of cross-sensitization between stress and cocaine, while stress-induced changes in the Pfc were not associated with cross-sensitization. PMID:22882295

  10. Interleukin-10 deficiency aggravates angiotensin II-induced cardiac remodeling in mice.

    PubMed

    Kwon, Woo-Young; Cha, Hye-Na; Heo, Jung-Yoon; Choi, Jung-Hyun; Jang, Byung Ik; Lee, In-Kye; Park, So-Young

    2016-02-01

    This study examined the role of interleukin (IL)-10 in angiotensin II-induced cardiac remodeling. Angiotensin II was infused subcutaneously (1.1mg/kg/day) for one week in IL-10 knockout and wild-type mice, after which cardiac function and hypertrophy were assessed by echocardiogram. IL-10 gene expression in the heart was increased by angiotensin II infusion. Plasma levels of brain natriuretic peptide (BNP) and gene expression of BNP in the heart were increased by IL-10 deficiency or angiotensin II, and plasma BNP levels were further increased by IL-10 deficiency with angiotensin II. IL-10 deficiency increased the left ventricular dimension, whereas treatment with angiotensin II increased heart weight. Angiotensin II significantly reduced cardiac function in IL-10 knockout mice compared with wild-type mice. Gene expression of tumor necrosis factor-α and interleukin-6 was increased by IL-10 deficiency or angiotensin II infusion, and these increases were further enhanced by IL-10 deficiency with angiotensin II. Gene expression of collagen I/III and collagen III protein levels were increased by angiotensin II but not by IL-10 deficiency. Gene expression of matrix metalloproteinase2/9 was increased by IL-10 deficiency or angiotensin II, and this expression was further increased by IL-10 deficiency with angiotensin II. Akt phosphorylation was increased by IL-10 deficiency or angiotensin II and further increased by IL-10 deficiency with angiotensin II. Phosphorylation of p38 was increased by IL-10 deficiency. These results suggest that IL-10 deficiency causes deterioration in cardiac functions in angiotensin II-infused mice, suggesting that IL-10 plays a protective role against angiotensin II-induced cardiac remodeling. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. PLC-gamma1 and Rac1 coregulate EGF-induced cytoskeleton remodeling and cell migration.

    PubMed

    Li, Siwei; Wang, Qian; Wang, Yi; Chen, Xinmei; Wang, Zhixiang

    2009-06-01

    It is well established that epidermal growth factor (EGF) induces the cytoskeleton reorganization and cell migration through two major signaling cascades: phospholipase C-gamma1 (PLC-gamma1) and Rho GTPases. However, little is known about the cross talk between PLC-gamma1 and Rho GTPases. Here we showed that PLC-gamma1 forms a complex with Rac1 in response to EGF. This interaction is direct and mediated by PLC-gamma1 Src homology 3 (SH3) domain and Rac1 (106)PNTP(109) motif. This interaction is critical for EGF-induced Rac1 activation in vivo, and PLC-gamma1 SH3 domain is actually a potent and specific Rac1 guanine nucleotide exchange factor in vitro. We have also demonstrated that the interaction between PLC-gamma1 SH3 domain and Rac1 play a significant role in EGF-induced F-actin formation and cell migration. We conclude that PLC-gamma1 and Rac1 coregulate EGF-induced cell cytoskeleton remodeling and cell migration by a direct functional interaction.

  12. A joined role of canopy and reversal cells in bone remodeling--lessons from glucocorticoid-induced osteoporosis.

    PubMed

    Jensen, Pia Rosgaard; Andersen, Thomas Levin; Hauge, Ellen-Margrethe; Bollerslev, Jens; Delaissé, Jean-Marie

    2015-04-01

    Successful bone remodeling demands that osteoblasts restitute the bone removed by osteoclasts. In human cancellous bone, a pivotal role in this restitution is played by the canopies covering the bone remodeling surfaces, since disruption of canopies in multiple myeloma, postmenopausal- and glucocorticoid-induced osteoporosis is associated with the absence of progression of the remodeling cycle to bone formation, i.e., uncoupling. An emerging concept explaining this critical role of canopies is that they represent a reservoir of osteoprogenitors to be delivered to reversal surfaces. In postmenopausal osteoporosis, this concept is supported by the coincidence between the absence of canopies and scarcity of cells on reversal surfaces together with abortion of the remodeling cycle. Here we tested whether this concept holds true in glucocorticoid-induced osteoporosis. A histomorphometric analysis of iliac crest biopsies from patients exposed to long-term glucocorticoid treatment revealed a subpopulation of reversal surfaces corresponding to the characteristics of arrest found in postmenopausal osteoporosis. Importantly, these arrested reversal surfaces were devoid of canopy coverage in almost all biopsies, and their prevalence correlated with a deficiency in bone forming surfaces. Taken together with the other recent data, the functional link between canopies, reversal surface activity, and the extent of bone formation surface in postmenopausal- and glucocorticoid-induced osteoporosis, supports a model where bone restitution during remodeling demands recruitment of osteoprogenitors from the canopy onto reversal surfaces. These data suggest that securing the presence of functional local osteoprogenitors deserves attention in the search of strategies to prevent the bone loss that occurs during bone remodeling in pathological situations.

  13. Intercellular Adhesion Molecule-1 and Vascular Cell Adhesion Molecule Are Induced by Ionizing Radiation on Lymphatic Endothelium.

    PubMed

    Rodriguez-Ruiz, María E; Garasa, Saray; Rodriguez, Inmaculada; Solorzano, Jose Luis; Barbes, Benigno; Yanguas, Alba; Teijeira, Alvaro; Etxeberria, Iñaki; Aristu, José Javier; Halin, Cornelia; Melero, Ignacio; Rouzaut, Ana

    2017-02-01

    The goal of this study was to assess the effects of ionizing radiation on the expression of the integrin ligands ICAM-1 and VCAM that control leucocyte transit by lymphatic endothelial cells. Confluent monolayers of primary human lymphatic endothelial cells (LEC) were irradiated with single dose of 2, 5, 10 or 20 Gy, with 6 MeV-x-rays using a Linear-Accelerator. ICAM-1 and VCAM expression was determined by flow cytometry. Human tissue specimens received a single dose of 20 Gy with 15 MeV-x-rays. MC38, B16-OVA or B16-VEGF-C tumors grown in C57BL/6 mice were irradiated with single dose of 20Gy using a Linear-Accelerator fitted with a 10mm Radiosurgery collimator. Clinical samples were obtained from patients previous and 4 weeks after complete standard radiotherapy. ICAM-1 and VCAM expression was detected in all tissue specimens by confocal microscopy. To understand the role of TGFβ in this process anti-TGFβ blocking mAb were injected i.p. 30min before radiotherapy. Cell adhesion to irradiated LEC was analyzed in adhesion experiments performed in the presence or in the absence of anti- TGFβ and /or anti-ICAM1 blocking mAb. We demonstrate that lymphatic endothelial cells in tumor samples experience induction of surface ICAM-1 and VCAM when exposed to ionizing radiation in a dose- and time-dependent manner. These effects can be recapitulated in cultured LEC, and are in part mediated by TGFβ. These data are consistent with increases in ICAM-1 and VCAM expression on LYVE-1+ endothelial cells in freshly explanted human tumor tissue and in mouse transplanted tumors after radiotherapy. Finally, ICAM-1 and VCAM expression accounts for enhanced adherence of human T lymphocytes to irradiated LEC. Our results show induction of ICAM-1 and VCAM on LVs in irradiated lesions and offer a starting point for elucidating the biological and therapeutic implications of targeting leukocyte traffic in combination to immunotherapy. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Insights into the pathogenesis of disease in human lymphatic filariasis.

    PubMed

    Nutman, Thomas B

    2013-09-01

    Although two thirds of the 120 million people infected with lymph-dwelling filarial parasites have subclinical infections, ∼40 million have lymphedema and/or other pathologic manifestations including hydroceles (and other forms of urogenital disease), episodic adenolymphangitis, lymphedema, and (in its most severe form) elephantiasis. Adult filarial worms reside in the lymphatics and lymph nodes and induce lymphatic dilatation. Progressive lymphatic damage and pathology results primarily from the host inflammatory response to the parasites but also perhaps from the host inflammatory response to the parasite's Wolbachia endosymbiont and as a consequence of superimposed bacterial or fungal infections. This review will attempt to shed light on disease pathogenesis in lymphatic filariasis.

  15. Epac1 and Epac2 are differentially involved in inflammatory and remodeling processes induced by cigarette smoke

    PubMed Central

    Oldenburger, Anouk; Timens, Wim; Bos, Sophie; Smit, Marieke; Smrcka, Alan V.; Laurent, Anne-Coline; Cao, Junjun; Hylkema, Machteld; Meurs, Herman; Maarsingh, Harm; Lezoualc'h, Frank; Schmidt, Martina

    2014-01-01

    Cigarette smoke (CS) induces inflammatory responses characterized by increase of immune cells and cytokine release. Remodeling processes, such as mucus hypersecretion and extracellular matrix protein production, are also directly or indirectly induced by CS. Recently, we showed that activation of the exchange protein directly activated by cAMP (Epac) attenuates CS extract-induced interleukin (IL)-8 release from cultured airway smooth muscle cells. Using an acute, short-term model of CS exposure, we now studied the role of Epac1, Epac2, and the Epac effector phospholipase-Cε (PLCε) in airway inflammation and remodeling in vivo. Compared to wild-type mice exposed to CS, the number of total inflammatory cells, macrophages, and neutrophils and total IL-6 release was lower in Epac2−/− mice, which was also the case for neutrophils and IL-6 in PLCε−/− mice. Taken together, Epac2, acting partly via PLCε, but not Epac1, enhances CS-induced airway inflammation in vivo. In total lung homogenates of Epac1−/− mice, MUC5AC and matrix remodeling parameters (transforming growth factor-β1, collagen I, and fibronectin) were increased at baseline. Our findings suggest that Epac1 primarily is capable of inhibiting remodeling processes, whereas Epac2 primarily increases inflammatory processes in vivo.—Oldenburger, A., Timens, W., Bos, S., Smit, M., Smrcka, A. V., Laurent, A.-C., Cao, J., Hylkema, M., Meurs, H., Maarsingh, H., Lezoualc'h, F., and Schmidt, M. Epac1 and Epac2 are differentially involved in inflammatory and remodeling processes induced by cigarette smoke. PMID:25103224

  16. Vitamin D attenuates cytokine-induced remodeling in human fetal airway smooth muscle cells.

    PubMed

    Britt, Rodney D; Faksh, Arij; Vogel, Elizabeth R; Thompson, Michael A; Chu, Vivian; Pandya, Hitesh C; Amrani, Yassine; Martin, Richard J; Pabelick, Christina M; Prakash, Y S

    2015-06-01

    Asthma in the pediatric population remains a significant contributor to morbidity and increasing healthcare costs. Vitamin D3 insufficiency and deficiency have been associated with development of asthma. Recent studies in models of adult airway diseases suggest that the bioactive Vitamin D3 metabolite, calcitriol (1,25-dihydroxyvitamin D3 ; 1,25(OH)2 D3 ), modulates responses to inflammation; however, this concept has not been explored in developing airways in the context of pediatric asthma. We used human fetal airway smooth muscle (ASM) cells as a model of the early postnatal airway to explore how calcitriol modulates remodeling induced by pro-inflammatory cytokines. Cells were pre-treated with calcitriol and then exposed to TNFα or TGFβ for up to 72 h. Matrix metalloproteinase (MMP) activity, production of extracellular matrix (ECM), and cell proliferation were assessed. Calcitriol attenuated TNFα enhancement of MMP-9 expression and activity. Additionally, calcitriol attenuated TNFα and TGFβ-induced collagen III expression and deposition, and separately, inhibited proliferation of fetal ASM cells induced by either inflammatory mediator. Analysis of signaling pathways suggested that calcitriol effects in fetal ASM involve ERK signaling, but not other major inflammatory pathways. Overall, our data demonstrate that calcitriol can blunt multiple effects of TNFα and TGFβ in developing airway, and point to a potentially novel approach to alleviating structural changes in inflammatory airway diseases of childhood.

  17. Olmesartan ameliorates pressure overload-induced cardiac remodeling through inhibition of TAK1/p38 signaling in mice.

    PubMed

    Wu, Lianpin; Mei, Liqin; Chong, Lin; Huang, Yinqing; Li, Yuechun; Chu, Maoping; Yang, Xiangjun

    2016-01-15

    Many studies have demonstrated the potent effects of ARB administration on heart failure. However, the mechanism of the potent effects of ARB on cardiac remodeling is less well understood. We investigated the role of Olmesartan on the fibrosis and hypertrophy in mouse heart. We employed TAC surgery, a mouse model of chronic cardiac failure. All the mice were separated into three groups: the sham group, TAC group and TAC plus Olmesartan group (given Olmesartan treatment after TAC). We analyzed left ventricle remodeling, and function by echocardiography or pathology. We further detected the level of marker genes involved in fibrosis and hypertrophy and in cultured neonatal rat cardiac fibroblasts and myocytes infected by constitutively active TAK1 and p38MAPK. After TAC, all the mice developed hypertrophy, worse cardiac function and malignant remodeling in left ventricle. Olmesartan improved heart remodeling and function without changing pressure of blood. Moreover, Olmesartan reduced the level of transforming growth factor β activated kinase-1 (TAK1) and phospho-p38MAPK. In neonatal rat cardiac fibroblast cells and cardiomyocytes, Olmesartan also decreased TAK1 and p38MAPK activation triggered by TGFβ1 or AngII. The inhibitory effect of Olmesartan was abrogated by overexpression of constitutively active TAK1 and p38MAPK by adenovirus system. Our results suggest Olmesartan improves heart remodeling and function induced by pressure overload. P38MAPK inactivation attenuated by olmesartan via inhibition of TAK1 pathway plays an important role in the process. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Nanoscale analysis of caspofungin-induced cell surface remodelling in Candida albicans

    NASA Astrophysics Data System (ADS)

    El-Kirat-Chatel, Sofiane; Beaussart, Audrey; Alsteens, David; Jackson, Desmond N.; Lipke, Peter N.; Dufrêne, Yves F.

    2013-01-01

    The advent of fungal pathogens that are resistant to the classic repertoire of antifungal drugs has increased the need for new therapeutic agents. A prominent example of such a novel compound is caspofungin, known to alter cell wall biogenesis by inhibiting β-1,3-d-glucan synthesis. Although much progress has been made in understanding the mechanism of action of caspofungin, little is known about its influence on the biophysical properties of the fungal cells. Here, we use atomic force microscopy (AFM) to demonstrate that caspofungin induces major remodelling of the cell surface properties of Candida albicans. Caspofungin causes major morphological and structural alterations of the cells, which correlate with a decrease of the cell wall mechanical strength. Moreover, we find that the drug induces the massive exposure of the cell adhesion protein Als1 on the cell surface and leads to increased cell surface hydrophobicity, two features that trigger cell aggregation. This behaviour is not observed in yeast species lacking Als1, demonstrating the key role that the protein plays in determining the aggregation phenotype of C. albicans. The results show that AFM opens up new avenues for understanding the molecular bases of microbe-drug interactions and for developing new therapeutic agents.The advent of fungal pathogens that are resistant to the classic repertoire of antifungal drugs has increased the need for new therapeutic agents. A prominent example of such a novel compound is caspofungin, known to alter cell wall biogenesis by inhibiting β-1,3-d-glucan synthesis. Although much progress has been made in understanding the mechanism of action of caspofungin, little is known about its influence on the biophysical properties of the fungal cells. Here, we use atomic force microscopy (AFM) to demonstrate that caspofungin induces major remodelling of the cell surface properties of Candida albicans. Caspofungin causes major morphological and structural alterations of the

  19. Genetics of lymphatic anomalies

    PubMed Central

    Brouillard, Pascal; Boon, Laurence; Vikkula, Miikka

    2014-01-01

    Lymphatic anomalies include a variety of developmental and/or functional defects affecting the lymphatic vessels: sporadic and familial forms of primary lymphedema, secondary lymphedema, chylothorax and chylous ascites, lymphatic malformations, and overgrowth syndromes with a lymphatic component. Germline mutations have been identified in at least 20 genes that encode proteins acting around VEGFR-3 signaling but also downstream of other tyrosine kinase receptors. These mutations exert their effects via the RAS/MAPK and the PI3K/AKT pathways and explain more than a quarter of the incidence of primary lymphedema, mostly of inherited forms. More common forms may also result from multigenic effects or post-zygotic mutations. Most of the corresponding murine knockouts are homozygous lethal, while heterozygotes are healthy, which suggests differences in human and murine physiology and the influence of other factors. PMID:24590274

  20. Improvement of cardiac function and neurological remodeling in a patient with tachycardia-induced cardiomyopathy after catheter ablation.

    PubMed

    Omichi, Chikaya; Tanaka, Takeshi; Kakizawa, Yoshiko; Yamada, Ayako; Ishii, Yasuhiro; Nagashima, Hirotaka; Kanmatsuse, Katsuo; Endo, Masahiro

    2009-08-01

    Incessant ventricular tachycardia and long-standing ectopic beats lead to tachycardia-induced cardiomyopathy. Catheter ablation eliminates ventricular tachycardia and reverses left ventricular (LV) dysfunction. 201-Thallium ((201)Tl) scintigraphy demonstrates perfusion defects with ischemic cardiomyopathy. Reversible perfusion defects are observed even in non-ischemic cardiomyopathy, related to regional flow or metabolism derangements. 123-I-metaiodobezylguanidine ((123)I-MIBG) scintigraphy delineates regional cardiac sympathetic denervation and heterogeneity. We demonstrated the progression of tachycardia-induced cardiomyopathy in a patient with idiopathic LV outflow tract tachycardia using (201)Tl and (123)I-MIBG scintigraphic findings. Regional defects were reversed predominantly in the basal interventricular septal wall in (201)Tl scintigraphy and (123)I-MIBG scintigraphic findings. This report suggests that incessant ventricular tachycardia or long-standing ventricular ectopic beats may develop adverse myocardial remodeling and sympathetic neurological remodeling. Treatment with catheter ablation for tachycardia-induced cardiomyopathy can reverse sympathetic neurological remodeling as well as myocardial structural remodeling.

  1. P2y12 Receptor Promotes Pressure Overload-Induced Cardiac Remodeling via Platelet-Driven Inflammation in Mice.

    PubMed

    Wu, Lujin; Zhao, Fujie; Dai, Meiyan; Li, Huaping; Chen, Chen; Nie, Jiali; Wang, Peihua; Wang, Dao Wen

    2017-10-01

    Inflammation plays a critical role in adverse cardiac remodeling and heart failure. The P2y12 receptor is one of the predominant activating receptors for platelets, thus initiating inflammatory responses under various diseases. In this study, we investigated the functional significance of P2y12-mediated platelet activation in pressure overload-induced cardiac remodeling. Notably, P2y12 knockout (P2y12(-/-)) mice exhibited suppressed transverse aortic constriction-induced changes in cardiac hypertrophy, collagen synthesis, inflammatory cell recruitment, and cardiac dysfunction. Activated platelets and platelet-leukocyte aggregates were markedly downregulated in P2y12 knockout mice compared with wild-type counterparts after transverse aortic constriction. Moreover, bone marrow chimera experiments revealed that wild-type recipients of P2y12 knockout bone marrow markedly improved cardiac function and attenuated cardiac remodeling, reversed by wild-type platelets reinjection. Platelet depletion and P-selectin inhibition mimicked these protective effects by limiting the interaction between activated platelets and leukocytes. Furthermore, activated wild-type platelets directly induced cardiomyocyte hypertrophy and collagen synthesis via α-granule exocytosis, vanished in P2y12 knockout platelets or those administered anti-NSF (N-ethlymalimide-sensitive factor) antibodies. The results suggest that P2y12-mediated platelet activation promotes cardiac remodeling by triggering a series of inflammatory changes and interacting with leukocytes and endotheliocytes. © 2017 American Heart Association, Inc.

  2. Glucocorticoid-induced p11 over-expression and chromatin remodeling: a novel molecular mechanism of traumatic stress?

    PubMed

    Zhang, Lei; Li, He; Hu, Xianzhang; Li, Xiao Xia; Smerin, Stanley; Ursano, Robert

    2011-06-01

    While the actions of glucocorticoids on brain function have been comprehensively studied, understanding of the underlying genomic mechanisms is advancing slowly. Recently, it was found that p11 is associated with traumatic stress and depression, and glucocorticoids regulate expression of the p11 gene. The ligand-activated glucocorticoid receptor (GR) interacts with two glucocorticoid response elements (GREs) in the p11 promoter region to up-regulate the p11 gene. RU486, a glucocorticoid receptor antagonist, and mutation of GREs both block glucocorticoid-induced p11 over-expression, suggesting that glucocorticoid-induced p11 over-expression is mediated by GR and GREs. Thus, the p11 gene can be transcriptionally activated. There is evidence that this transcriptional activation is mediated by the remodeling of chromatin complexes in response to glucocorticoid receptor-regulated promotors. The regulation of eukaryotic gene expression by chromatin remodeling is complex and is essential for numerous cellular processes. The association of linker-histone, non-histone and heterochromatin-specific proteins plays a key role in the generation of higher-order chromatin structures. Understanding the chromatin remodeling involved in the glucocorticoid-mediated increase of p11 expression by stress may clarify stress-induced over-expression of p11 and also identify a new therapeutic target for post-traumatic disorder and depressive disorders, i.e., chromatin remodeling.

  3. Dietary nitrite supplementation attenuates cardiac remodeling in l-NAME-induced hypertensive rats.

    PubMed

    Sonoda, Kunihiro; Ohtake, Kazuo; Uchida, Hiroyuki; Ito, Junta; Uchida, Masaki; Natsume, Hideshi; Tamada, Hazuki; Kobayashi, Jun

    2017-07-01

    Loss of nitric oxide (NO) bioavailability underlies the development of hypertensive heart disease. We investigated the effects of dietary nitrite on N(G)-nitro-l-arginine methyl ester (l-NAME)-induced hypertension. Sprague-Dawley rats were divided into five groups: an untreated control group, an l-NAME-treated group, and three other l-NAME-treated groups supplemented with 10 mg/L or 100 mg/L of nitrite or 100 mg/L of captopril in drinking water. After the 8-week experimental period, mean arterial blood pressure was measured, followed by sampling of blood and heart tissue for assessment of nitrite/nitrate levels in the plasma and heart, the plasma level of angiotensin II (AT II), and the heart transcriptional levels of AT II type 1 receptor (AT1R), transforming growth factor-β1 (TGF-β1), and connective tissue proteins such as type 1 collagen and fibronectin. Heart tissue was analyzed by histopathological morphometry, including assessments of ventricular and coronary vascular hypertrophy and fibrosis, as well as immunohistochemistry analyses of myocardial expression of AT1R. l-NAME treatment reduced the plasma nitrate level and led to the development of hypertension, with increased plasma levels of AT II and increased heart transcriptional levels of AT1R and TGF-β1-mediated connective tissue proteins, showing myocardial and coronary arteriolar hypertrophy and fibrosis. However, dietary nitrite supplementation inhibited TGF-β1-mediated cardiac remodeling by suppressing AT II and AT1R. These results suggest that dietary nitrite levels achievable via a daily high-vegetable diet could improve hypertensive heart disease by inhibiting AT II-AT1R-mediated cardiac remodeling. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. A transcriptome signature of endothelial lymphatic cells coexists with the chronic oxidative stress signature in radiation-induced post-radiotherapy breast angiosarcomas.

    PubMed

    Hadj-Hamou, Nabila-Sandra; Laé, Marick; Almeida, Anna; de la Grange, Pierre; Kirova, Youlia; Sastre-Garau, Xavier; Malfoy, Bernard

    2012-07-01

    Radiation-induced breast angiosarcomas are rare but recognized complication of breast cancer radiotherapy and are of poor prognosis. Little is known about the genetic abnormalities present in these secondary tumors. Herein, we investigated the differences in the genome and in the transcriptome that discriminate these tumors as a function of their etiology. Seven primary breast angiosarcomas and 18 secondary breast angiosarcomas arising in the irradiation field of a radiotherapy were analyzed. Copy number alterations and gene expression were analyzed using Affymetrix SNP 6.0 Array and Affymetrix Exon Arrays, respectively. We showed that two transcriptome signatures of the radiation tumorigenesis coexisted in these tumors. One was histology specific and correctly discriminated 100% of the primary tumors from the radiation-induced tumors. The deregulation of marker genes, including podoplanin (PDPN), prospero homeobox 1 (PROX-1), vascular endothelial growth factor 3 (VEGFR3) and endothelin receptor A (EDNRA), suggests that the radiation-induced breast angiosarcomas developed from radiation-stimulated lymphatic endothelial cells. None of the genes of the histology-specific signature were present in our previously published signature of the radiation tumorigenesis which shows the presence of a chronic oxidative stress in radiation-induced sarcomas of various histologies. Nevertheless, this oxidative stress signature classified correctly 88% of the breast angiosarcomas as a function of the etiology. In contrast, MYC amplification, which is observed in all radiation-induced tumors but also at a low rate in primary tumors, was not a marker of the radiation tumorigenesis.

  5. Functional and structural remodeling of glutamate synapses in prefrontal and frontal cortex induced by behavioral stress.

    PubMed

    Musazzi, Laura; Treccani, Giulia; Popoli, Maurizio

    2015-01-01

    Increasing evidence has shown that the pathophysiology of neuropsychiatric disorders, including mood disorders, is associated with abnormal function and regulation of the glutamatergic system. Consistently, preclinical studies on stress-based animal models of pathology showed that glucocorticoids and stress exert crucial effects on neuronal excitability and function, especially in cortical and limbic areas. In prefrontal and frontal cortex, acute stress was shown to induce enhancement of glutamate release/transmission dependent on activation of corticosterone receptors. Although the mechanisms whereby stress affects glutamate transmission have not yet been fully understood, it was shown that synaptic, non-genomic action of corticosterone is required to increase the readily releasable pool of glutamate vesicles, but is not sufficient to enhance transmission in prefrontal and frontal cortex. Slower, partly genomic mechanisms are probably necessary for the enhancement of glutamate transmission induced by stress. Combined evidence has suggested that the changes in glutamate release and transmission are responsible for the dendritic remodeling and morphological changes induced by stress and it has been argued that sustained alterations of glutamate transmission may play a key role in the long-term structural/functional changes associated with mood disorders in patients. Intriguingly, modifications of the glutamatergic system induced by stress in the prefrontal cortex seem to be biphasic. Indeed, while the fast response to stress suggests an enhancement in the number of excitatory synapses, synaptic transmission and working memory, long-term adaptive changes - including those consequent to chronic stress - induce opposite effects. Better knowledge of the cellular effectors involved in this biphasic effect of stress may be useful to understand the pathophysiology of stress-related disorders, and open new paths for the development of therapeutic approaches.

  6. Functional and Structural Remodeling of Glutamate Synapses in Prefrontal and Frontal Cortex Induced by Behavioral Stress

    PubMed Central

    Musazzi, Laura; Treccani, Giulia; Popoli, Maurizio

    2015-01-01

    Increasing evidence has shown that the pathophysiology of neuropsychiatric disorders, including mood disorders, is associated with abnormal function and regulation of the glutamatergic system. Consistently, preclinical studies on stress-based animal models of pathology showed that glucocorticoids and stress exert crucial effects on neuronal excitability and function, especially in cortical and limbic areas. In prefrontal and frontal cortex, acute stress was shown to induce enhancement of glutamate release/transmission dependent on activation of corticosterone receptors. Although the mechanisms whereby stress affects glutamate transmission have not yet been fully understood, it was shown that synaptic, non-genomic action of corticosterone is required to increase the readily releasable pool of glutamate vesicles, but is not sufficient to enhance transmission in prefrontal and frontal cortex. Slower, partly genomic mechanisms are probably necessary for the enhancement of glutamate transmission induced by stress. Combined evidence has suggested that the changes in glutamate release and transmission are responsible for the dendritic remodeling and morphological changes induced by stress and it has been argued that sustained alterations of glutamate transmission may play a key role in the long-term structural/functional changes associated with mood disorders in patients. Intriguingly, modifications of the glutamatergic system induced by stress in the prefrontal cortex seem to be biphasic. Indeed, while the fast response to stress suggests an enhancement in the number of excitatory synapses, synaptic transmission and working memory, long-term adaptive changes – including those consequent to chronic stress – induce opposite effects. Better knowledge of the cellular effectors involved in this biphasic effect of stress may be useful to understand the pathophysiology of stress-related disorders, and open new paths for the development of therapeutic approaches. PMID

  7. Effect of gender on training-induced vascular remodeling in SHR.

    PubMed

    Amaral, S L; Michelini, L C

    2011-09-01

    There is accumulating evidence that physical inactivity, associated with the modern sedentary lifestyle, is a major determinant of hypertension. It represents the most important modifiable risk factor for cardiovascular diseases, which are the leading cause of morbidity and mortality for both men and women. In addition to involving sympathetic overactivity that alters hemodynamic parameters, hypertension is accompanied by several abnormalities in the skeletal muscle circulation including vessel rarefaction and increased arteriole wall-to-lumen ratio, which contribute to increased total peripheral resistance. Low-intensity aerobic training is a promising tool for the prevention, treatment and control of high blood pressure, but its efficacy may differ between men and women and between male and female animals. This review focuses on peripheral training-induced adaptations that contribute to a blood pressure-lowering effect, with special attention to differential responses in male and female spontaneously hypertensive rats (SHR). Heart, diaphragm and skeletal muscle arterioles (but not kidney arterioles) undergo eutrophic outward remodeling in trained male SHR, which contributed to a reduction of peripheral resistance and to a pressure fall. In contrast, trained female SHR showed no change in arteriole wall-to-lumen ratio and no pressure fall. On the other hand, training-induced adaptive changes in capillaries and venules (increased density) were similar in male and female SHR, supporting a similar hyperemic response to exercise.

  8. Increasing mitochondrial muscle fatty acid oxidation induces skeletal muscle remodeling toward an oxidative phenotype.

    PubMed

    Hénique, Carole; Mansouri, Abdelhak; Vavrova, Eliska; Lenoir, Véronique; Ferry, Arnaud; Esnous, Catherine; Ramond, Elodie; Girard, Jean; Bouillaud, Frédéric; Prip-Buus, Carina; Cohen, Isabelle

    2015-06-01

    Adult skeletal muscle is a dynamic, remarkably plastic tissue, which allows myofibers to switch from fast/glycolytic to slow/oxidative types and to increase mitochondrial fatty acid oxidation (mFAO) capacity and vascularization in response to exercise training. mFAO is the main muscle energy source during endurance exercise, with carnitine palmitoyltransferase 1 (CPT1) being the key regulatory enzyme. Whether increasing muscle mFAO affects skeletal muscle physiology in adulthood actually remains unknown. To investigate this, we used in vivo electrotransfer technology to express in mouse tibialis anterior (TA), a fast/glycolytic muscle, a mutated CPT1 form (CPT1mt) that is active but insensitive to malonyl-CoA, its physiologic inhibitor. In young (2-mo-old) adult mice, muscle CPT1mt expression enhanced mFAO (+40%), but also increased the percentage of oxidative fibers (+28%), glycogen content, and capillary-to-fiber density (+45%). This CPT1mt-induced muscle remodeling, which mimicked exercise-induced oxidative phenotype, led to a greater resistance to muscle fatigue. In the context of aging, characterized by sarcopenia and reduced oxidative capacity, CPT1mt expression in TAs from aged (20-mo-old) mice partially reversed aging-associated sarcopenia and fiber-type transition, and increased muscle capillarity. These findings provide evidence that mFAO regulates muscle phenotype and may be a potential target to combat age-related decline in muscle function.

  9. Nanoscale analysis of caspofungin-induced cell surface remodelling in Candida albicans

    PubMed Central

    El-Kirat-Chatel, Sofiane; Beaussart, Audrey; Alsteens, David; Jackson, Desmond N.; Lipke, Peter N.; Dufrêne, Yves F.

    2013-01-01

    The advent of fungal pathogens that are resistant to the classic repertoire of antifungal drugs has increased the need for new therapeutic agents. A prominent example of such novel compound is caspofungin, known to alter cell wall biogenesis by inhibiting β-1,3 D-glucan synthesis. Although much progress has been made in understanding the mechanism of action of caspofungin, little is known about its influence on the biophysical properties of the fungal cells. Here, we use atomic force microscopy to demonstrate that caspofungin induces major remodeling of the cell surface properties of Candida albicans. Caspofungin causes major morphological and structural alterations of the cells, which correlate with a decrease of the cell wall mechanical strength. Moreover, we find that the drug induces the massive exposure of the cell adhesion protein Als1 on the cell surface and leads to increased cell surface hydrophobicity, two features that trigger cell aggregation. This behaviour is not observed in yeast species lacking Als1, demonstrating the key role that the protein plays in determining the aggregation phenotype of C. albicans. The results show that AFM opens up new avenues for understanding the molecular bases of microbe-drug interactions and for developing new therapeutic agents. PMID:23262781

  10. Salt-Induced Remodeling of Spatially Restricted Clathrin-Independent Endocytic Pathways in Arabidopsis Root

    PubMed Central

    Baral, Anirban; Irani, Niloufer G.; Fujimoto, Masaru; Nakano, Akihiko; Mayor, Satyajit; Mathew, M.K.

    2015-01-01

    Endocytosis is a ubiquitous cellular process that is characterized well in animal cells in culture but poorly across intact, functioning tissue. Here, we analyze endocytosis throughout the Arabidopsis thaliana root using three classes of probes: a lipophilic dye, tagged transmembrane proteins, and a lipid-anchored protein. We observe a stratified distribution of endocytic processes. A clathrin-dependent endocytic pathway that internalizes transmembrane proteins functions in all cell layers, while a sterol-dependent, clathrin-independent pathway that takes up lipid and lipid-anchored proteins but not transmembrane proteins is restricted to the epidermal layer. Saline stress induces a third pathway that is clathrin-independent, nondiscriminatory in its choice of cargo, and operates across all layers of the root. Concomitantly, small acidic compartments in inner cell layers expand to form larger vacuole-like structures. Plants lacking function of the Rab-GEF (guanine nucleotide exchange factor) VPS9a (vacuolar protein sorting 9A) neither induce the third endocytic pathway nor expand the vacuolar system in response to salt stress. The plants are also hypersensitive to salt. Thus, saline stress reconfigures clathrin-independent endocytosis and remodels endomembrane systems, forming large vacuoles in the inner cell layers, both processes correlated by the requirement of VPS9a activity. PMID:25901088

  11. Loss of progesterone receptor-mediated actions induce preterm cellular and structural remodeling of the cervix and premature birth.

    PubMed

    Yellon, Steven M; Dobyns, Abigail E; Beck, Hailey L; Kurtzman, James T; Garfield, Robert E; Kirby, Michael A

    2013-01-01

    A decline in serum progesterone or antagonism of progesterone receptor function results in preterm labor and birth. Whether characteristics of premature remodeling of the cervix after antiprogestins or ovariectomy are similar to that at term was the focus of the present study. Groups of pregnant rats were treated with vehicle, a progesterone receptor antagonist (onapristone or mifepristone), or ovariectomized on day 17 postbreeding. As expected, controls given vehicle delivered at term while rats delivered preterm after progesterone receptor antagonist treatment or ovariectomy. Similar to the cervix before term, the preterm cervix of progesterone receptor antagonist-treated rats was characterized by reduced cell nuclei density, decreased collagen content and structure, as well as a greater presence of macrophages per unit area. Thus, loss of nuclear progesterone receptor-mediated actions promoted structural remodeling of the cervix, increased census of resident macrophages, and preterm birth much like that found in the cervix at term. In contrast to the progesterone receptor antagonist-induced advance in characteristics associated with remodeling, ovariectomy-induced loss of systemic progesterone did not affect hypertrophy, extracellular collagen, or macrophage numbers in the cervix. Thus, the structure and macrophage census in the cervix appear sufficient for premature ripening and birth to occur well before term. With progesterone receptors predominantly localized on cells other than macrophages, the findings suggest that interactions between cells may facilitate the loss of progesterone receptor-mediated actions as part of a final common mechanism that remodels the cervix in certain etiologies of preterm and with parturition at term.

  12. Mas receptor contributes to pregnancy-induced cardiac remodeling.

    PubMed

    Carmos-Silva, Cintia; Almeida, Jônathas Fernandes Queiroz de; Macedo, Larissa Matuda; Melo, Marcos Barrouin B; Pedrino, Gustavo Rodrigues; Santos, Fernanda Fernanda Cristina Alcantara; Biancardi, Manoel Francisco; Santos, Robson Augusto Souza Dos Augusto Souza; Carvalho, Adryano Augustto; Mendes, Elizabeth Pereira; Colugnati, Diego Basile; Mazaro-Costa, Renata; Castro, Carlos Henrique de

    2016-09-13

    Previous studies have demonstrated a protective effect of the Ang-(1-7)/Mas receptor axis on pathological cardiac hypertrophy. Also, the involvement of Mas receptor in the exercise-induced cardiac hypertrophy has been suggested. However, the role of the Ang-(1-7)/Mas receptor on pregnancy-induced cardiac remodeling remains unknown. The objective of this study was to evaluate the participation of the Mas receptor in the development of the cardiac hypertrophy and fibrosis induced by gestation. Female Wistar rats were shared in 3 groups: control , pregnant , and pregnant treated with Mas receptor antagonist A-779 . Wild type (WT) and Mas-knockout mice (KO) were distributed in non-pregnant  and pregnant  groups. Systolic blood pressure (SBP) was measured by tail-cuff plethysmography. The medial part of the left ventricle (LV) was collected for histological analysis. Echocardiographic analysis was used to evaluate the cardiac function. SBP was not changed by pregnancy or A-779 treatment in the Wistar rats. Pharmacological blockade or genetic deletion of Mas receptor attenuates the pregnancy-induced myocyte hypertrophy. The treatment with A-779 or genetic deletion of the Mas receptor increased the collagen III deposition in LV from pregnant animals without changing the fibroblast proliferation. KO mice presented a lower ejection fraction, fraction shortening, stroke volume and higher end systolic volume compared to WT. Interestingly, the pregnancy restored these parameters. In conclusion, these data show that while Mas receptor blockade or deletion decreases physiological hypertrophy of pregnancy, it is associated with more extracellular matrix deposition. These alterations are associated with improvement of the cardiac function through Mas-independent mechanism. ©2016 The Author(s).

  13. Lattice Boltzmann simulations of lymphatic pumping

    NASA Astrophysics Data System (ADS)

    Kunert, Christian; Padera, Tim P.; Munn, Lance L.

    2012-02-01

    Lymphatic flow plays an important role in the progress of many diseases, including lymphedema and metastasis. However lymphatic pumping and flow is poorly understood. Here, we present a computer model that is based on biological observations of lymphatic pumping. Fluid flow is simulated by a D2Q9 lattice Boltzmann model. The boundary of the vessels moves according to shear-induced nitric oxide production, and wall motion transfers momentum to the fluid to induce flow. Because the model only includes local properties, it can be highly parallelized. In our case we utilize graphic processors (GPU) to achieve high performance computation. We show that the model provides stable pumping over a wide range of parameter values, with optimum flow achieved in the biological ranges. Furthermore, we investigate the efficiency by analyzing the flow rate and pumping frequency in order to compare the behavior of the model with existing in vivo data.

  14. Roles of Caveolin-1 in Angiotensin II-Induced Hypertrophy and Inward Remodeling of Cerebral Pial Arterioles.

    PubMed

    Umesalma, Shaikamjad; Houwen, Frederick Keith; Baumbach, Gary L; Chan, Siu-Lung

    2016-03-01

    Angiotensin II (Ang II) is a major determinant of inward remodeling and hypertrophy in pial arterioles that may have an important role in stroke during chronic hypertension. Previously, we found that epidermal growth factor receptor is critical in Ang II-mediated hypertrophy that may involve caveolin-1 (Cav-1). In this study, we examined the effects of Cav-1 and matrix metalloproteinase-9 (MMP9) on Ang II-mediated structural changes in pial arterioles. Cav-1-deficient (Cav-1(-/-)), MMP9-deficient (MMP9(-/-)), and wild-type mice were infused with either Ang II (1000 ng/kg per minute) or saline via osmotic minipumps for 28 days (n=6-8 per group). Systolic arterial pressure was measured by a tail-cuff method. Pressure and diameter of pial arterioles were measured through an open cranial window in anesthetized mice. Cross-sectional area of the wall was determined histologically in pressurized fixed pial arterioles. Expression of Cav-1, MMP9, phosphorylated epidermal growth factor receptor, and Akt was determined by Western blotting and immunohistochemistry. Deficiency of Cav-1 or MMP9 did not affect Ang II-induced hypertension. Ang II increased the expression of Cav-1, phosphorylated epidermal growth factor receptor, and Akt in wild-type mice, which was attenuated in Cav-1(-/-) mice. Ang II-induced hypertrophy, inward remodeling, and increased MMP9 expression in pial arterioles were prevented in Cav-1(-/-) mice. Ang II-mediated increases in MMP9 expression and inward remodeling, but not hypertrophy, were prevented in MMP9(-/-) mice. In conclusion, Cav-1 is essential in Ang II-mediated inward remodeling and hypertrophy in pial arterioles. Cav-1-induced MMP9 is exclusively involved in inward remodeling, not hypertrophy. Further studies are needed to determine the role of Akt in Ang II-mediated hypertrophy. © 2016 American Heart Association, Inc.

  15. Regular endurance exercise induces expansive arterial remodelling in the trained limbs of healthy men

    PubMed Central

    Dinenno, Frank A; Tanaka, Hirofumi; Monahan, Kevin D; Clevenger, Christopher M; Eskurza, Iratxe; DeSouza, Christopher A; Seals, Douglas R

    2001-01-01

    In experimental animals chronic elevations in arterial blood flow increase the lumen diameter and reduce the intima-media thickness (IMT) of the arterial segment involved. We determined whether intermittent elevations in active muscle blood flow associated with regular aerobic leg exercise induced such expansive arterial remodelling in the common femoral artery of humans. In the cross-sectional study 53 sedentary (47 ± 2 years) and 55 endurance exercise-trained (47 ± 2 years) men were studied. Common femoral artery lumen diameter (B-mode ultrasound) was 7 % greater (9.62 ± 0.12 vs. 9.03 ± 0.13 mm), and femoral IMT (0.46 ± 0.02 vs. 0.55 ± 0.02 mm) and IMT/lumen ratio were 16–21 % smaller in the endurance-trained men (all P < 0.001). Basal femoral artery blood flow (duplex ultrasound) was not different, shear stress tended to be lower (P = 0.08), and mean femoral tangential wall stress was 30 % higher in the endurance-trained men (P < 0.001). In the intervention study 22 men (51 ± 2 years) were studied before and after 3 months of regular aerobic leg exercise (primarily walking). After training, the femoral diameter increased by 9 % (8.82 ± 0.18 vs. 9.60 ± 0.20 mm), and IMT (0.65 ± 0.05 vs. 0.56 ± 0.05 mm) and the IMT/lumen ratio were ≈15–20 % smaller (all P < 0.001). Basal femoral blood flow and shear stress were not different after training, whereas the mean femoral tangential wall stress increased by 31 %. The changes in arterial structure were not related to changes in risk factors for atherosclerosis. Our results are consistent with the concept that regular aerobic leg exercise induces expansive arterial remodelling in the femoral artery of healthy men. This adaptive process is produced by even a moderate training stimulus, is not obviously dependent on corresponding improvements in risk factors for atherosclerosis, and is robust, occurring in healthy men of different ages. PMID:11433009

  16. Spleen and Lymphatic System (For Parents)

    MedlinePlus

    ... Your 1- to 2-Year-Old Spleen and Lymphatic System KidsHealth > For Parents > Spleen and Lymphatic System A ... help fight off infection. About the Spleen and Lymphatic System One of the lymphatic system's major jobs is ...

  17. Spleen and Lymphatic System (For Parents)

    MedlinePlus

    ... TV, Video Games, and the Internet Spleen and Lymphatic System KidsHealth > For Parents > Spleen and Lymphatic System Print ... help fight off infection. About the Spleen and Lymphatic System One of the lymphatic system's major jobs is ...

  18. Gold nanoparticle-filled biodegradable photopolymer scaffolds induced muscle remodeling: in vitro and in vivo findings.

    PubMed

    Zsedenyi, Adam; Farkas, Balazs; Abdelrasoul, Gaser N; Romano, Ilaria; Gyukity-Sebestyen, Edina; Nagy, Katalin; Harmati, Maria; Dobra, Gabriella; Kormondi, Sandor; Decsi, Gabor; Nemeth, Istvan Balazs; Diaspro, Alberto; Brandi, Fernando; Beke, Szabolcs; Buzas, Krisztina

    2017-03-01

    Therapeutic stem cell transplantation bears the promise of new directions in organ and tissue replacement, but a number of its difficulties and perils are also well known. Our goal was to develop a method of transplantation by which the transplanted cells remain confined to the transplantation site and induce favorable processes. With the help of mask-projection excimer laser stereolithography, 3D hybrid nanoscaffolds were fabricated from biodegradable, photocurable PPF:DEF resin with incorporated gold nanoparticles (Au NPs). The scaffolds were tested in vitro and in vivo in order to find out about their biocompatibility and fitness for our purposes. In vitro, macrophages and mouse autologous adipose stem cells (ASCs) were seeded over the hybrid scaffolds and non-hybrid (with Au NPs) scaffolds for 4days. The hybrid nanocomposite greater stem cell dispension and stem cell adhesion than PPF scaffolds without Au NPs, but such a difference was not seen in the case of macrophages. In vivo, stem cells, scaffoldings and scaffoldings covered in stem cells were transplanted under the back skin of mice. After 14days, blood samples were taken and the affected skin area was excised. Cytokine and chemokine profiling did not indicate elevated immunomediators in the sera of experimental animals. Interestingly, the autologous-stem-cell-seeded hybrid nanocomposite scaffold induced muscle tissue regeneration after experimental wound generation in vivo. We could not observe such stem cell-induced tissue regeneration when no scaffolding was used. We conclude that PPF:DEF resin nanoscaffolds with incorporated gold nanoparticles offer a safe and efficient alternative for the enhancement of local tissue remodeling. The results also support the idea that adipose derived stem cells are an optimal cell type for the purposes of regenerative musculoskeletal tissue engineering.

  19. Remodeling of heterochromatin induced by heavy metals in extreme old age.

    PubMed

    Lezhava, Teimuraz; Monaselidze, Jamlet; Jokhadze, Tinatin; Gorgoshidze, Maia; Kiladze, Maia; Gaiozishvili, Maia

    2011-09-01

    The levels of chromosome instability and heat absorption of chromatin have been studied in cultured lymphocytes derived from blood of 80-93- and 18-30-year-old individuals, under the effect of heavy metal Cu(II) and Cd(II) salts. The analysis of the results obtained indicates that 50 μM Cu(II) induced a significantly higher level of cells with chromosome aberrations in old donors (13.8 ± 1.5% vs control, 3.8 ± 1.7%), whereas treatment with 100 μM Cd(II) did not induce any changes in the background index. Analysis of the lymphocyte melting curves showed that Cu(II) ions caused more effective condensation of heterochromatin in old healthy individuals compared with young donors, which was expressed by the increase of the T (m) of elderly chromatin by ~3°C compared with the norm. Treatment of lymphocyte chromatin of old individuals with 100 μM Cd(II) caused decondensation (deheterochromatinization) of both the facultative and constitutive domains of heterochromatin. The deheterochromatinization T (m) was decreased by ~3-3.5°C compared with the T (m) observed for young individuals. Thus, the chromatin of cultured lymphocytes from the old-aged individuals underwent modification under the influence of copper and cadmium salts. Cu(II) caused additional heterochromatinization of heterochromatin, and Cd(II) caused deheterochromatinization of facultative and constitutive heterochromatin. Our data may be important as new information on the remodeling of constitutive and facultative heterochromatin induced by heavy metals in aging, aging pathology, and pathology linked with metal ions.

  20. Neural network remodeling underlying motor map reorganization induced by rehabilitative training after ischemic stroke.

    PubMed

    Okabe, Naohiko; Shiromoto, Takashi; Himi, Naoyuki; Lu, Feng; Maruyama-Nakamura, Emi; Narita, Kazuhiko; Iwachidou, Nobuhisa; Yagita, Yoshiki; Miyamoto, Osamu

    2016-12-17

    Motor map reorganization is believed to be one mechanism underlying rehabilitation-induced functional recovery. Although the ipsilesional secondary motor area has been known to reorganize motor maps and contribute to rehabilitation-induced functional recovery, it is unknown how the secondary motor area is reorganized by rehabilitative training. In the present study, using skilled forelimb reaching tasks, we investigated neural network remodeling in the rat rostral forelimb area (RFA) of the secondary motor area during 4weeks of rehabilitative training. Following photothrombotic stroke in the caudal forelimb area (CFA), rehabilitative training led to task-specific recovery and motor map reorganization in the RFA. A second injury to the RFA resulted in reappearance of motor deficits. Further, when both the CFA and RFA were destroyed simultaneously, rehabilitative training no longer improved task-specific recovery. In neural tracer studies, although rehabilitative training did not alter neural projection to the RFA from other brain areas, rehabilitative training increased neural projection from the RFA to the lower spinal cord, which innervates the muscles in the forelimb. Double retrograde tracer studies revealed that rehabilitative training increased the neurons projecting from the RFA to both the upper cervical cord, which innervates the muscles in the neck, trunk, and part of the proximal forelimb, and the lower cervical cord. These results suggest that neurons projecting to the upper cervical cord provide new connections to the denervated forelimb area of the spinal cord, and these new connections may contribute to rehabilitation-induced task-specific recovery and motor map reorganization in the secondary motor area.

  1. Regulatory mechanism of gallic acid against advanced glycation end products induced cardiac remodeling in experimental rats.

    PubMed

    Umadevi, Subramanian; Gopi, Venkatachalam; Elangovan, Vellaichamy

    2014-02-05

    Advanced glycation end products (AGEs) play a major role in the development of cardiovascular disorders in diabetic patients. Recent studies evidenced the beneficial role of phytochemicals in reducing the risk of cardiovascular diseases. Hence the present study was framed to investigate the protective role of Gallic acid (GA) on AGEs induced cardiac fibrosis. Rats were infused with in vitro prepared AGEs (50mg/kg BW-intravenous injection) for 30 days. Further, GA (25mg/kgBW) was administered to rats along with AGEs. On infusion of AGEs, induction of fibrotic markers, collagen deposition, oxidative marker NADPH oxidase (NOX-p47 phox subunit), AGE receptor (RAGE) and cytokines expression was evaluated in the heart tissues using RT-PCR, Western blot and immunostaining methods. AGEs infusion significantly (P<0.01) increased the HW/BW ratio and fibrosis (4-fold) with increased expression of matrix genes MMP-2 and -9 (P<0.01, respectively) in the heart tissues. Whereas, administration of GA along with AGEs infusion prevented the fibrosis induced by AGEs. Further, GA treatment effectively prevented the AGEs mediated up-regulation of pro-fibrotic genes and ECM proteins such as TNF-α, TGF-β, MMP-2 and -9 expression. In addition, the increased expression of NOX (P<0.01), RAGE (P<0.01), NF-κB (P<0.01) and ERK 1/2 on AGEs infusion were normalized by GA treatment. Thus the present study shows the protective effect of GA on the fibrotic response and cardiac remodeling process induced by advanced glycation end products from external sources. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. Role of epidermal growth factor receptor and endoplasmic reticulum stress in vascular remodeling induced by angiotensin II.

    PubMed

    Takayanagi, Takehiko; Kawai, Tatsuo; Forrester, Steven J; Obama, Takashi; Tsuji, Toshiyuki; Fukuda, Yamato; Elliott, Katherine J; Tilley, Douglas G; Davisson, Robin L; Park, Joon-Young; Eguchi, Satoru

    2015-06-01

    The mechanisms by which angiotensin II (AngII) elevates blood pressure and enhances end-organ damage seem to be distinct. However, the signal transduction cascade by which AngII specifically mediates vascular remodeling such as medial hypertrophy and perivascular fibrosis remains incomplete. We have previously shown that AngII-induced epidermal growth factor receptor (EGFR) transactivation is mediated by disintegrin and metalloproteinase domain 17 (ADAM17), and that this signaling is required for vascular smooth muscle cell hypertrophy but not for contractile signaling in response to AngII. Recent studies have implicated endoplasmic reticulum (ER) stress in hypertension. Interestingly, EGFR is capable of inducing ER stress. The aim of this study was to test the hypothesis that activation of EGFR and ER stress are critical components required for vascular remodeling but not hypertension induced by AngII. Mice were infused with AngII for 2 weeks with or without treatment of EGFR inhibitor, erlotinib, or ER chaperone, 4-phenylbutyrate. AngII infusion induced vascular medial hypertrophy in the heart, kidney and aorta, and perivascular fibrosis in heart and kidney, cardiac hypertrophy, and hypertension. Treatment with erlotinib as well as 4-phenylbutyrate attenuated vascular remodeling and cardiac hypertrophy but not hypertension. In addition, AngII infusion enhanced ADAM17 expression, EGFR activation, and ER/oxidative stress in the vasculature, which were diminished in both erlotinib-treated and 4-phenylbutyrate-treated mice. ADAM17 induction and EGFR activation by AngII in vascular cells were also prevented by inhibition of EGFR or ER stress. In conclusion, AngII induces vascular remodeling by EGFR activation and ER stress via a signaling mechanism involving ADAM17 induction independent of hypertension. © 2015 American Heart Association, Inc.

  3. Mechanical Forces and Lymphatic Transport

    PubMed Central

    Breslin, Jerome W.

    2014-01-01

    This review examines current understanding of how the lymphatic vessel network can optimize lymph flow in response to various mechanical forces. Lymphatics are organized as a vascular tree, with blind-ended initial lymphatics, precollectors, prenodal collecting lymphatics, lymph nodes, postnodal collecting lymphatics and the larger trunks (thoracic duct and right lymph duct) that connect to the subclavian veins. The formation of lymph from interstitial fluid depends heavily on oscillating pressure gradients to drive fluid into initial lymphatics. Collecting lymphatics are segmented vessels with unidirectional valves, with each segment, called a lymphangion, possessing an intrinsic pumping mechanism. The lymphangions propel lymph forward against a hydrostatic pressure gradient. Fluid is returned to the central circulation both at lymph nodes and via the larger lymphatic trunks. Several recent developments are discussed, including: evidence for the active role of endothelial cells in lymph formation; recent developments on how inflow pressure, outflow pressure, and shear stress affect pump function of the lymphangion; lymphatic valve gating mechanisms; collecting lymphatic permeability; and current interpretations of the molecular mechanisms within lymphatic endothelial cells and smooth muscle. Improved understanding of the physiological mechanisms by lymphatic vessels sense mechanical stimuli, integrate the information, and generate the appropriate response is key for determining the pathogenesis of lymphatic insufficiency and developing treatments for lymphedema. PMID:25107458

  4. miR-222 is Necessary for Exercise-induced Cardiac Growth and Protects Against Pathological Cardiac Remodeling

    PubMed Central

    Liu, Xiaojun; Xiao, Junjie; Zhu, Han; Wei, Xin; Platt, Colin; Damilano, Federico; Xiao, Chunyang; Bezzerides, Vassilios; Boström, Pontus; Che, Lin; Zhang, Chunxiang; Spiegelman, Bruce M; Rosenzweig, Anthony

    2015-01-01

    SUMMARY Exercise induces physiological cardiac growth and protects the heart against pathological remodeling. Recent work suggests exercise also enhances the heart’s capacity for repair, which could be important for regenerative therapies. While microRNAs are important in certain cardiac pathologies, less is known about their functional roles in exercise-induced cardiac phenotypes. We profiled cardiac microRNA expression in two distinct models of exercise and found microRNA-222 (miR-222) was upregulated in both. Downstream miR-222 targets modulating cardiomyocyte phenotype were identified, including HIPK1 and Homeobox-1. Inhibition of miR-222 in vivo completely blocked cardiac and cardiomyocyte growth in response to exercise, while reducing markers of cardiomyocyte proliferation. Importantly, mice with inducible cardiomyocyte miR-222 expression were resistant to adverse cardiac remodeling and dysfunction after ischemic injury. These studies implicate miR-222 as necessary for exercise-induced cardiomyocyte growth and proliferation in the adult mammalian heart and show that it is sufficient to protect the heart against adverse remodeling. PMID:25863248

  5. miR-222 is necessary for exercise-induced cardiac growth and protects against pathological cardiac remodeling.

    PubMed

    Liu, Xiaojun; Xiao, Junjie; Zhu, Han; Wei, Xin; Platt, Colin; Damilano, Federico; Xiao, Chunyang; Bezzerides, Vassilios; Boström, Pontus; Che, Lin; Zhang, Chunxiang; Spiegelman, Bruce M; Rosenzweig, Anthony

    2015-04-07

    Exercise induces physiological cardiac growth and protects the heart against pathological remodeling. Recent work suggests exercise also enhances the heart's capacity for repair, which could be important for regenerative therapies. While microRNAs are important in certain cardiac pathologies, less is known about their functional roles in exercise-induced cardiac phenotypes. We profiled cardiac microRNA expression in two distinct models of exercise and found microRNA-222 (miR-222) was upregulated in both. Downstream miR-222 targets modulating cardiomyocyte phenotypes were identified, including HIPK1 and HMBOX1. Inhibition of miR-222 in vivo completely blocked cardiac and cardiomyocyte growth in response to exercise while reducing markers of cardiomyocyte proliferation. Importantly, mice with inducible cardiomyocyte miR-222 expression were resistant to adverse cardiac remodeling and dysfunction after ischemic injury. These studies implicate miR-222 as necessary for exercise-induced cardiomyocyte growth and proliferation in the adult mammalian heart and show that it is sufficient to protect the heart against adverse remodeling.

  6. Soy protein hydrolysate ameliorates cardiovascular remodeling in rats with L-NAME-induced hypertension.

    PubMed

    Yang, Hsin-Yi; Yang, Suh-Ching; Chen, Shu-Tzu; Chen, Jiun-Rong

    2008-12-01

    Pepsin-digested soy protein hydrolysate has been reported to be responsible for many of the physiological benefits associated with soy protein consumption. In the present study, we investigated the effects of soy protein hydrolysate with angiotensin-converting enzyme (ACE) inhibitory potential on the blood pressure and cardiovascular remodeling in rats with N(omega)-nitro-L-arginine methyl ester hydrochloride (L-NAME)-induced hypertension. Rats were fed a diet containing L-NAME (50 mg/kg body weight) with or without soy protein hydrolysate (1%, 3% or 5%) for 6 weeks. We found that ingestion of soy protein hydrolysate retarded the development of hypertension during the 6-week experimental period without affecting the amount of food intake. Although there was no difference in plasma ACE activity or tissue nitric oxide levels, ACE activity in the heart of rats consuming soy protein hydrolysate was significantly lower than that of the control group. Moreover, cardiac malonaldehyde and tumor necrosis factor-alpha concentrations were also lower in the soy protein hydrolysate group. No difference in plasminogen activator inhibitor-1 level was found in plasma or cardiovascular tissue. In the histopathological analysis, we also found that soy protein hydrolysate ameliorated inflammation and left ventricle hypertrophy in the heart. These findings suggest that soy protein hydrolysate might not only improve the balance between circulating nitric oxide and renin-angiotensin system but also show beneficial effects on cardiovascular tissue through its ACE inhibitory activity.

  7. Rapamycin transiently induces mitochondrial remodeling to reprogram energy metabolism in old hearts

    PubMed Central

    Chiao, Ying Ann; Kolwicz, Stephen C.; Basisty, Nathan; Gagnidze, Arni; Zhang, Julia; Gu, Haiwei; Djukovic, Danijel; Beyer, Richard P.; Raftery, Daniel; MacCoss, Michael; Tian, Rong; Rabinovitch, Peter S.

    2016-01-01

    Rapamycin, an inhibitor of mTOR signaling, has been shown to reverse diastolic dysfunction in old mice in 10 weeks, highlighting its therapeutic potential for a poorly treatable condition. However, the mechanisms and temporal regulation of its cardiac benefits remain unclear. We show that improved diastolic function in old mice begins at 2-4 weeks, progressing over the course of 10-week treatment. While TORC1-mediated S6 phosphorylation and TORC2 mediated AKT and PKCα phosphorylation are inhibited throughout the course of treatment, rapamycin inhibits ULK phosphorylation and induces autophagy during just the first week of treatment, returning to baseline at two weeks and after. Concordantly, markers of mitochondrial biogenesis increase over the first two weeks of treatment and return to control levels thereafter. This transient induction of autophagy and mitochondrial biogenesis suggests that damaged mitochondria are replaced by newly synthesized ones to rejuvenate mitochondrial homeostasis. This remodeling is shown to rapidly reverse the age-related reduction in fatty acid oxidation to restore a more youthful substrate utilization and energetic profile in old isolated perfused hearts, and modulates the myocardial metabolome in vivo. This study demonstrates the differential and dynamic mechanisms following rapamycin treatment and highlights the importance of understanding the temporal regulation of rapamycin effects. PMID:26872208

  8. Low Carbohydrate/High Fat Diet Attenuates Pressure Overload Induced Ventricular Remodeling and Dysfunction

    PubMed Central

    Duda, Monika K.; O’Shea, Karen M.; Lei, Biao; Barrows, Brian R.; Azimzadeh, Agnes M.; McElfresh, Tracy E.; Hoit, Brian D.; Kop, Willem J.; Stanley, William C.

    2009-01-01

    Background It is not known how carbohydrate and fat intake impact the development of left ventricular (LV) hypertrophy and contractile dysfunction in response to pressure overload. We hypothesized that a low carbohydrate/high fat diet prevents LV hypertrophy and dysfunction compared to high carbohydrate diets. Methods and Results Rats were fed high carbohydrate diets comprised of either starch or sucrose, or a low carbohydrate/high fat diet, and underwent abdominal aortic banding (AAB) for two months. AAB increased LV mass with all diets. LV end diastolic and systolic volumes, and the ratio of the mRNA for myosin heavy chainβ/α were increased with both high carbohydrate diets, but not with the low carbohydrate/high fat diet. Circulating levels of insulin and leptin, both stimulants for cardiac growth, were lower, and free fatty acids higher, with the low carbohydrate/high fat diet compared to high carbohydrate diets. Among AAB animals LV volumes were positively correlated with insulin, and LV mass correlated with leptin. Conclusion A low carbohydrate/high fat diet attenuated pressure overload-induced LV remodeling compared to high carbohydrate diets. This effect corresponded to lower insulin and leptin concentrations, suggesting they may contribute to the development of LV hypertrophy and dysfunction under conditions of pressure overload. PMID:18474346

  9. Selective presynaptic terminal remodeling induced by spatial, but not cued, learning: a quantitative confocal study.

    PubMed

    McGonigal, R; Tabatadze, N; Routtenberg, A

    2012-06-01

    The hippocampal mossy fibers (MFs) are capable of behaviorally selective, use-dependent structural remodeling. Indeed, we previously observed a new layer of Timm's staining induced in the stratum oriens (SO) in CA3 after spatial but not cued water maze learning (Rekart et al., (2007) Learn Mem 14:416-421). This led to the prediction that there is a learning-specific induction of presynaptic terminal plasticity of MF axons. This study confirms this prediction demonstrating, at the confocal level of analysis, terminal-specific, and behavior-selective presynaptic structural plasticity linked to long-term memory. Male adult Wistar rats were trained for 5 days to locate a hidden or visible platform in a water maze and a retention test was performed 7 days later. MF terminal subtypes, specifically identified by an antibody to zinc transporter 3 (ZnT3), were counted from confocal z-stacks in the stratum lucidum (SL) and the SO. In hidden platform trained rats, there was a significant increase in the number of large MF terminals (LMTs, 2.5-10 μm diameter, >2 μm(2) area) compared to controls both in the proximal SL (P < 0.05) and in the SO (P < 0.01). Surprisingly, there was no detectable increase in small MF terminals (SMTs, 0.5-2 μm diameter, <2 μm(2) area) in either SL or SO as a consequence of training. This distinction of the two MF terminal types is functionally important as LMTs synapse on CA3 pyramidal neurons, while SMTs are known to target inhibitory interneurons. The present findings highlight the pivotal role in memory of presynaptic structural plasticity. Because the "sprouting" observed is specific to the LMT, with no detectable change in the number of the SMT, learning may enhance net excitatory input to CA3 pyramidal neurons. Given the sparse coding of the MF-CA3 connection, and the role that granule cells play in pattern separation, the remodeling observed here may be expected to have a major impact on the long-term integration of spatial context into

  10. Selective presynaptic terminal remodeling induced by spatial, but not cued, learning: a quantitative confocal study

    PubMed Central

    McGonigal, R.; Tabatadze, N.; Routtenberg, A.

    2011-01-01

    The hippocampal mossy fibers (MFs) are capable of behaviorally-selective, use-dependent structural remodeling. Indeed, we previously observed a new layer of Timm’s staining induced in the stratum oriens (SO) in CA3 after spatial but not cued water maze learning (Rekart et al., Learn. Mem. 2007; 14:416–421). This led to the prediction that there is a learning-specific induction of presynaptic terminal plasticity of MF axons. The present study confirms this prediction demonstrating, at the confocal level of analysis, terminal-specific and behavior-selective presynaptic structural plasticity linked to long-term memory. Male adult Wistar rats were trained for 5d to locate a hidden or visible platform in a water maze and a retention test was performed 7d later. MF terminal subtypes, specifically identified by an antibody to zinc transporter 3 (ZnT3), were counted from confocal z-stacks in the stratum lucidum (SL) and the SO. In hidden platform trained rats there was a significant increase in the number of large MF terminals (LMTs, 2.5–10µm diameter, >2µm2 area) compared to controls both in the proximal SL (p <0.05) and in the SO (p < 0.01). Surprisingly, there was no detectable increase in small MF terminals (SMTs, 0.5–2µm diameter, <2µm2 area) in either SL or SO as a consequence of training. This distinction of the two MF terminal types is functionally important as LMTs synapse on CA3 pyramidal neurons, while SMTs are known to target inhibitory interneurons. The present findings highlight the pivotal role in memory of presynaptic structural plasticity. Because the ‘sprouting’ observed is specific to the LMT, with no detectable change in the number of the SMT, learning may enhance net excitatory input to CA3 pyramidal neurons. Given the sparse coding of the MF-CA3 connection, and the role that granule cells play in pattern separation, the remodeling observed here may be expected to have a major impact on the long-term integration of spatial context into

  11. Influences of rapid pacing-induced electrical remodeling on pharmacological manipulation of the atrial refractoriness in rabbits.

    PubMed

    Chiba, Toshiki; Kondo, Naoto; Takahara, Akira

    2016-03-01

    Electrical remodeling plays a pivotal role in maintaining the reentry during atrial fibrillation. In this study, we assessed influence of electrical remodeling on pharmacological manipulation of the atrial refractoriness in rabbits. We used an atrial electrical remodeling model of the rabbit, subjected to rapid atrial pacing (RAP; 600 beats/min) for 2-4 weeks, leading to shortening of atrial effective refractory period (AERP). Intravenous administration of dl-sotalol (6 mg/kg), bepridil (1 mg/kg), amiodarone (10 mg/kg) or vernakalant (3 mg/kg) significantly prolonged the AERP both in the control and RAP rabbits. The extents in the RAP rabbits were similar to those in the control animals. On the other hand, prolonging effects of intravenously administered ranolazine (10 mg/kg) or tertiapin-Q (0.03 mg/kg) on the AERP in the RAP rabbits were more potent than those in the control animals. These results suggest that rapid pacing-induced electrical remodeling effectively modified the prolonging effects of ranolazine and tertiapin-Q on the AERP in contrast to those of clinically available antiarrhythmic drugs, dl-sotalol, bepridil amiodarone and vernakalant.

  12. What Is the Lymphatic System?

    MedlinePlus

    ... 9) 2017 NLN International Conference What is the Lymphatic System? To better understand lymphedema , we first must understand the normal lymphatic system (see diagram) . This system functions parallel to the ...

  13. What Is the Lymphatic System?

    MedlinePlus

    ... information and to apply now! What is the Lymphatic System? To better understand lymphedema , we first must understand the normal lymphatic system (see diagram) . This system functions parallel to the ...

  14. Dynamic remodeling of the guinea pig intrinsic cardiac plexus induced by chronic myocardial infarction.

    PubMed

    Hardwick, Jean C; Ryan, Shannon E; Beaumont, Eric; Ardell, Jeffrey L; Southerland, E Marie

    2014-04-01

    Myocardial infarction (MI) is associated with remodeling of the heart and neurohumoral control systems. The objective of this study was to define time-dependent changes in intrinsic cardiac (IC) neuronal excitability, synaptic efficacy, and neurochemical modulation following MI. MI was produced in guinea pigs by ligation of the coronary artery and associated vein on the dorsal surface of the heart. Animals were recovered for 4, 7, 14, or 50 days. Intracellular voltage recordings were obtained in whole mounts of the cardiac neuronal plexus to determine passive and active neuronal properties of IC neurons. Immunohistochemical analysis demonstrated an immediate and persistent increase in the percentage of IC neurons immunoreactive for neuronal nitric oxide synthase. Examination of individual neuronal properties demonstrated that after hyperpolarizing potentials were significantly decreased in both amplitude and time course of recovery at 7 days post-MI. These parameters returned to control values by 50 days post-MI. Synaptic efficacy, as determined by the stimulation of axonal inputs, was enhanced at 7 days post-MI only. Neuronal excitability in absence of agonist challenge was unchanged following MI. Norepinephrine increased IC excitability to intracellular current injections, a response that was augmented post-MI. Angiotensin II potentiation of norepinephrine and bethanechol-induced excitability, evident in controls, was abolished post-MI. This study demonstrates that MI induces both persistent and transient changes in IC neuronal functions immediately following injury. Alterations in the IC neuronal network, which persist for weeks after the initial insult, may lead to alterations in autonomic signaling and cardiac control.

  15. Tauroursodeoxycholic acid (TUDCA) attenuates pressure overload-induced cardiac remodeling by reducing endoplasmic reticulum stress.

    PubMed

    Rani, Shilpa; Sreenivasaiah, Pradeep Kumar; Kim, Jin Ock; Lee, Mi Young; Kang, Wan Seok; Kim, Yong Sook; Ahn, Youngkeun; Park, Woo Jin; Cho, Chunghee; Kim, Do Han

    2017-01-01

    Pressure overload in the heart induces pathological hypertrophy and is associated with cardiac dysfunction. Apoptosis and fibrosis signaling initiated by the endoplasmic reticulum stress (ERS) is known to contribute to these maladaptive effects. The aim of this study was to investigate whether reduction of ERS by a known chemical chaperone, tauroursodeoxycholic acid (TUDCA) can attenuate pressure overload-induced cardiac remodeling in a mouse model of transverse aortic constriction (TAC). Oral administration of TUDCA at a dose of 300 mg/kg body weight (BW) in the TUDCA-TAC group reduced ERS markers (GRP78, p-PERK, and p-eIf2α), compared to the Vehicle (Veh)-TAC group. TUDCA administration, for 4 weeks after TAC significantly reduced cardiac hypertrophy as shown by the reduced heart weight (HW) to BW ratio, and expression of hypertrophic marker genes (ANF, BNP, and α-SKA). Masson's trichrome staining showed that myocardial fibrosis and collagen deposition were also significantly reduced in the TUDCA-TAC group. We also found that TUDCA significantly decreased expression of TGF-β signaling proteins and collagen isoforms. TUDCA administration also reduced cardiac apoptosis and the related proteins in the TUDCA-TAC group. Microarray analysis followed by gene ontology (GO) and pathway analysis demonstrated that extracellular matrix genes responsible for hypertrophy and fibrosis, and mitochondrial genes responsible for apoptosis and fatty acid metabolism were significantly altered in the Veh-TAC group, but the alterations were normalized in the TUDCA-TAC group, suggesting potential of TUDCA in treatment of heart diseases related to pressure-overload.

  16. Long-term in vivo Resistin Overexpression Induces Myocardial Dysfunction and Remodeling in Rats

    PubMed Central

    Chemaly, Elie R.; Hadri, Lahouaria; Zhang, Shihong; Kim, Maengjo; Kohlbrenner, Erik; Sheng, Jipo; Liang, Lifan; Chen, Jiqiu; K-Raman, Purushothaman; Hajjar, Roger J.; Lebeche, Djamel

    2011-01-01

    We have previously reported that resistin induces hypertrophy and impairs contractility in isolated rat cardiomyocytes. To examine the long-term cardiovascular effects of resistin, we induced in vivo overexpression of resistin using adeno-associated virus serotype 9 injected by tail vein in rats and compared to control animals. Ten weeks after viral injection, overexpression of resistin was associated with increased ratio of left ventricular (LV) weight/body weight increased end-systolic LV volume and significant decrease in LV contractility, measured by the end-systolic pressure volume relationship slope in LV pressure volume loops, compared to controls. At the molecular level, mRNA expression of ANF and β-MHC, and protein levels of phospholamban were increased in the resistin group without a change in the level of SERCA2a protein expression. Increased fibrosis by histology, associated with increased mRNA levels of collagen, fibronectin and connective tissue growth factor were observed in the resistin-overexpressing hearts. Resistin overexpression was also associated with increased apoptosis in vivo, along with an apoptotic molecular phenotype in vivo and in vitro. Resistin-overexpressing LV tissue had higher levels of TNF-α receptor 1 and iNOS, and reduced levels of eNOS. Cardiomyocytes overexpressing resistin in vitro produced larger amounts of TNFα in the medium, had increased phosphorylation of IκBα and displayed increased intracellular reactive oxygen species (ROS) content with increased expression and activity of ROS-producing NADPH oxidases compared to controls. Long-term resistin overexpression is associated with a complex phenotype of oxidative stress, inflammation, fibrosis, apoptosis and myocardial remodeling and dysfunction in rats. This phenotype recapitulates key features of diabetic cardiomyopathy. PMID:21549710

  17. Tauroursodeoxycholic acid (TUDCA) attenuates pressure overload-induced cardiac remodeling by reducing endoplasmic reticulum stress

    PubMed Central

    Rani, Shilpa; Sreenivasaiah, Pradeep Kumar; Kim, Jin Ock; Lee, Mi Young; Kang, Wan Seok; Kim, Yong Sook; Ahn, Youngkeun; Park, Woo Jin; Cho, Chunghee

    2017-01-01

    Pressure overload in the heart induces pathological hypertrophy and is associated with cardiac dysfunction. Apoptosis and fibrosis signaling initiated by the endoplasmic reticulum stress (ERS) is known to contribute to these maladaptive effects. The aim of this study was to investigate whether reduction of ERS by a known chemical chaperone, tauroursodeoxycholic acid (TUDCA) can attenuate pressure overload-induced cardiac remodeling in a mouse model of transverse aortic constriction (TAC). Oral administration of TUDCA at a dose of 300 mg/kg body weight (BW) in the TUDCA-TAC group reduced ERS markers (GRP78, p-PERK, and p-eIf2α), compared to the Vehicle (Veh)-TAC group. TUDCA administration, for 4 weeks after TAC significantly reduced cardiac hypertrophy as shown by the reduced heart weight (HW) to BW ratio, and expression of hypertrophic marker genes (ANF, BNP, and α-SKA). Masson's trichrome staining showed that myocardial fibrosis and collagen deposition were also significantly reduced in the TUDCA-TAC group. We also found that TUDCA significantly decreased expression of TGF-β signaling proteins and collagen isoforms. TUDCA administration also reduced cardiac apoptosis and the related proteins in the TUDCA-TAC group. Microarray analysis followed by gene ontology (GO) and pathway analysis demonstrated that extracellular matrix genes responsible for hypertrophy and fibrosis, and mitochondrial genes responsible for apoptosis and fatty acid metabolism were significantly altered in the Veh-TAC group, but the alterations were normalized in the TUDCA-TAC group, suggesting potential of TUDCA in treatment of heart diseases related to pressure-overload. PMID:28426781

  18. Human recombinant RNASET2-induced inflammatory response and connective tissue remodeling in the medicinal leech.

    PubMed

    Baranzini, Nicolò; Pedrini, Edoardo; Girardello, Rossana; Tettamanti, Gianluca; de Eguileor, Magda; Taramelli, Roberto; Acquati, Francesco; Grimaldi, Annalisa

    2017-01-09

    In recent years, several studies have demonstrated that the RNASET2 gene is involved in the control of tumorigenicity in ovarian cancer cells. Furthermore, a role in establishing a functional cross-talk between cancer cells and the surrounding tumor microenvironment has been unveiled for this gene, based on its ability to act as an inducer of the innate immune response. Although several studies have reported on the molecular features of RNASET2, the details on the mechanisms by which this evolutionarily conserved ribonuclease regulates the immune system are still poorly defined. In the effort to clarify this aspect, we report here the effect of recombinant human RNASET2 injection and its role in regulating the innate immune response after bacterial challenge in an invertebrate model, the medicinal leech. We found that recombinant RNASET2 injection induces fibroplasias, connective tissue remodeling and the recruitment of numerous infiltrating cells expressing the specific macrophage markers CD68 and HmAIF1. The RNASET2-mediated chemotactic activity for macrophages has been further confirmed by using a consolidated experimental approach based on injection of the Matrigel biomatrice (MG) supplemented with recombinant RNASET2 in the leech body wall. One week after injection, a large number of CD68(+) and HmAIF-1(+) macrophages massively infiltrated MG sponges. Finally, in leeches challenged with lipopolysaccharides (LPS) or with the environmental bacteria pathogen Micrococcus nishinomiyaensis, numerous macrophages migrating to the site of inoculation expressed high levels of endogenous RNASET2. Taken together, these results suggest that RNASET2 is likely involved in the initial phase of the inflammatory response in leeches.

  19. Forebrain CRHR1 deficiency attenuates chronic stress-induced cognitive deficits and dendritic remodeling

    PubMed Central

    Wang, Xiao-Dong; Chen, Yuncai; Wolf, Miriam; Wagner, Klaus V.; Liebl, Claudia; Scharf, Sebastian H.; Harbich, Daniela; Mayer, Bianca; Wurst, Wolfgang; Holsboer, Florian; Deussing, Jan M.; Baram, Tallie Z.; Müller, Marianne B.; Schmidt, Mathias V.

    2011-01-01

    Chronic stress evokes profound structural and molecular changes in the hippocampus, which may underlie spatial memory deficits. Corticotropin-releasing hormone (CRH) and CRH receptor 1 (CRHR1) mediate some of the rapid effects of stress on dendritic spine morphology and modulate learning and memory, thus providing a potential molecular basis for impaired synaptic plasticity and spatial memory by repeated stress exposure. Using adult male mice with CRHR1 conditionally inactivated in the forebrain regions, we investigated the role of CRH-CRHR1 signaling in the effects of chronic social defeat stress on spatial memory, the dendritic morphology of hippocampal CA3 pyramidal neurons, and the hippocampal expression of nectin-3, a synaptic cell adhesion molecule important in synaptic remodeling. In chronically stressed wild-type mice, spatial memory was disrupted, and the complexity of apical dendrites of CA3 neurons reduced. In contrast, stressed mice with forebrain CRHR1 deficiency exhibited normal dendritic morphology of CA3 neurons and mild impairments in spatial memory. Additionally, we showed that the expression of nectin-3 in the CA3 area was regulated by chronic stress in a CRHR1-dependent fashion and associated with spatial memory and dendritic complexity. Moreover, forebrain CRHR1 deficiency prevented the down-regulation of hippocampal glucocorticoid receptor expression by chronic stress but induced increased body weight gain during persistent stress exposure. These findings underscore the important role of forebrain CRH-CRHR1 signaling in modulating chronic stress-induced cognitive, structural and molecular adaptations, with implications for stress-related psychiatric disorders. PMID:21296667

  20. Neural Cell Adhesion Molecule NrCAM Regulates Semaphorin 3F-Induced Dendritic Spine Remodeling

    PubMed Central

    Demyanenko, Galina P.; Mohan, Vishwa; Zhang, Xuying; Brennaman, Leann H.; Dharbal, Katherine E.S.; Tran, Tracy S.; Manis, Paul B.

    2014-01-01

    Neuron-glial related cell adhesion molecule (NrCAM) is a regulator of axon growth and repellent guidance, and has been implicated in autism spectrum disorders. Here a novel postsynaptic role for NrCAM in Semaphorin3F (Sema3F)-induced dendritic spine remodeling was identified in pyramidal neurons of the primary visual cortex (V1). NrCAM localized to dendritic spines of star pyramidal cells in postnatal V1, where it was coexpressed with Sema3F. NrCAM deletion in mice resulted in elevated spine densities on apical dendrites of star pyramidal cells at both postnatal and adult stages, and electron microscopy revealed increased numbers of asymmetric synapses in layer 4 of V1. Whole-cell recordings in cortical slices from NrCAM-null mice revealed increased frequency of mEPSCs in star pyramidal neurons. Recombinant Sema3F-Fc protein induced spine retraction on apical dendrites of wild-type, but not NrCAM-null cortical neurons in culture, while re-expression of NrCAM rescued the spine retraction response. NrCAM formed a complex in brain with Sema3F receptor subunits Neuropilin-2 (Npn-2) and PlexinA3 (PlexA3) through an Npn-2-binding sequence (TARNER) in the extracellular Ig1 domain. A trans heterozygous genetic interaction test demonstrated that Sema3F and NrCAM pathways interacted in vivo to regulate spine density in star pyramidal neurons. These findings reveal NrCAM as a novel postnatal regulator of dendritic spine density in cortical pyramidal neurons, and an integral component of the Sema3F receptor complex. The results implicate NrCAM as a contributor to excitatory/inhibitory balance in neocortical circuits. PMID:25143608

  1. Lymphatic endothelial cells induce tolerance via PD-L1 and lack of costimulation leading to high-level PD-1 expression on CD8 T cells

    PubMed Central

    Tewalt, Eric F.; Cohen, Jarish N.; Rouhani, Sherin J.; Guidi, Cynthia J.; Qiao, Hui; Fahl, Shawn P.; Conaway, Mark R.; Bender, Timothy P.; Tung, Kenneth S.; Vella, Anthony T.; Adler, Adam J.; Chen, Lieping

    2012-01-01

    Lymphatic endothelial cells (LECs) induce peripheral tolerance by direct presentation to CD8 T cells (TCD8). We demonstrate that LECs mediate deletion only via programmed cell death-1 (PD-1) ligand 1, despite expressing ligands for the CD160, B- and T-lymphocyte attenuator, and lymphocyte activation gene-3 inhibitory pathways. LECs induce activation and proliferation of TCD8, but lack of costimulation through 4-1BB leads to rapid high-level expression of PD-1, which in turn inhibits up-regulation of the high-affinity IL-2 receptor that is necessary for TCD8 survival. Rescue of tyrosinase-specific TCD8 by interference with PD-1 or provision of costimulation results in autoimmune vitiligo, demonstrating that LECs are significant, albeit suboptimal, antigen-presenting cells. Because LECs express numerous peripheral tissue antigens, lack of costimulation coupled to rapid high-level up-regulation of inhibitory receptors may be generally important in systemic peripheral tolerance. PMID:22993390

  2. Neither normal nor diseased placentas contain lymphatic vessels.

    PubMed

    Castro, E; Tony Parks, W; Galambos, C

    2011-04-01

    Scant data on placental lymphatic vessels have pointed to the absence of lymphatic circulation. A recent study on mesenchymal dysplasia (MD), however, has identified pathologic lymphangiogenesis using the D2-40 lymphatic marker. These conflicting data have prompted us to investigate whether lymphatic vessels are present in normal developing placentas and in placental disorders characterized by cistern formation. Seventeen human placentas without significant pathological abnormality ranging from 12 to 39 weeks of gestational age were studied. Cisternal placental disorders were represented by mesenchymal dysplasia (n = 1), partial hydatitiform mole (n = 2), spontaneous abortion (n = 3) and complete hydatiform mole (n = 2). To identify lymphatic vessels, we used lymphatic endothelial markers Prox-1 and D2-40. The pan-endothelial marker CD31 was used to highlight overall placental vasculature and to determine if the lining cells of cisterns were of endothelial origin. Lymphatic marker positivity was assessed in maternal (decidual) as well as in fetal (chorionic villous) vasculature. No staining with Prox-1 or D2-40 was identified in fetal vessels in developing or term placentas, or in selected cisternal placental disorders, although both markers highlighted a number of thin-walled decidual vessels. Cistern lining cells were negative for Prox-1, D2-40 and CD31. D2-40 consistently marked stromal cells in chorionic villi and highlighted perivascular/pericellular extracellular matrix. We established that no lymphatic vasculature is present in the chorionic villi during development, at term or in selected edematous placental disorders. The cisternal lining cells are not endothelial cells; most likely they are of stromal cell origin. Lymphangiogenesis is a part of decidual vascular remodeling during gestation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Interleukin-6 Induces Vascular Endothelial Growth Factor-C Expression via Src-FAK-STAT3 Signaling in Lymphatic Endothelial Cells

    PubMed Central

    Huang, Shiu-Wen; Ou, George; Hsu, Ya-Fen; Hsu, Ming-Jen

    2016-01-01

    Elevated serum interleukin-6 (IL-6) levels correlates with tumor grade and poor prognosis in cancer patients. IL-6 has been shown to promote tumor lymphangiogenesis through vascular endothelial growth factor-C (VEGF-C) induction in tumor cells. We recently showed that IL-6 also induced VEGF-C expression in lymphatic endothelial cells (LECs). However, the signaling mechanisms involved in IL-6-induces VEGF-C induction in LECs remain incompletely understood. In this study, we explored the causal role of focal adhesion kinase (FAK) in inducing VEGF-C expression in IL-6-stimulated murine LECs (SV-LECs). FAK signaling blockade by NSC 667249 (a FAK inhibitor) attenuated IL-6-induced VEGF-C expression and VEGF-C promoter-luciferase activities. IL-6’s enhancing effects of increasing FAK, ERK1/2, p38MAPK, C/EBPβ, p65 and STAT3 phosphorylation as well as C/EBPβ-, κB- and STAT3-luciferase activities were reduced in the presence of NSC 667249. STAT3 knockdown by STAT3 siRNA abrogated IL-6’s actions in elevating VEGF-C mRNA and protein levels. Moreover, Src-FAK signaling blockade reduced IL-6’s enhancing effects of increasing STAT3 binding to the VEGF-C promoter region, cell migration and endothelial tube formation of SV-LECs. Together these results suggest that IL-6 increases VEGF-C induction and lymphangiogenesis may involve, at least in part, Src-FAK-STAT3 cascade in LECs. PMID:27383632

  4. Lymphatics and the breast

    MedlinePlus Videos and Cool Tools

    ... a very worrisome role in the spread of breast cancer. Components of the lymphatic system called lymph nodes ... may result in the formation of a secondary cancer mass in a different location of the body. Regular breast self examinations can help to detect tumors earlier ...

  5. [Pleural lymphatics and effusions].

    PubMed

    Mordant, P; Arame, A; Legras, A; Le Pimpec Barthes, F; Riquet, M

    2013-06-01

    The pleural lymphatic system has a great absorption capacity. Its most known function is fluid resorption. The pleura which cover the lungs (visceral pleura), the mediastinum, diaphragm and thoracic wall (parietal pleura) are formed by a mesothelial cell layer (mesothelium). This permeable layer is in direct contact with the vascular endothelium. The mesothelium is based over a connective tissue (interstitium) containing the blood and lymphatic vessels. The primary lymphatic vessels drain interstitium but are also in direct contact with pleural space by the stoma or openings, situated in the lower parts of parietal pleura, i.e: diaphragm, over lower ribs and mediastinum but not existing in the adjacent visceral pleura. In addition, a part of interstitial pulmonary fluid entered in the pleural cavity by passing the visceral pleura would be absorbed by these openings. The resorption process is active and directly related to the function of smooth muscles of lymphatic vessels. Besides resorption, we must emphasize that this "pumping" activity is permanent and the origin of negative pressure (the pleural void) in pleural cavity, a unique property. The other resorbed elements are molecules, bacterial and cellular debris, cells, red blood and cancer cells. Copyright © 2013. Published by Elsevier Masson SAS.

  6. Vibration induced osteogenic commitment of mesenchymal stem cells is enhanced by cytoskeletal remodeling but not fluid shear.

    PubMed

    Uzer, Gunes; Pongkitwitoon, Suphannee; Ete Chan, M; Judex, Stefan

    2013-09-03

    Consistent across studies in humans, animals and cells, the application of vibrations can be anabolic and/or anti-catabolic to bone. The physical mechanisms modulating the vibration-induced response have not been identified. Recently, we developed an in vitro model in which candidate parameters including acceleration magnitude and fluid shear can be controlled independently during vibrations. Here, we hypothesized that vibration induced fluid shear does not modulate mesenchymal stem cell (MSC) proliferation and mineralization and that cell's sensitivity to vibrations can be promoted via actin stress fiber formation. Adipose derived human MSCs were subjected to vibration frequencies and acceleration magnitudes that induced fluid shear stress ranging from 0.04 Pa to 5 Pa. Vibrations were applied at magnitudes of 0.15 g, 1g, and 2g using frequencies of both 100 Hz and 30 Hz. After 14 d and under low fluid shear conditions associated with 100 Hz oscillations, mineralization was greater in all vibrated groups than in controls. Greater levels of fluid shear produced by 30 Hz vibrations enhanced mineralization only in the 2g group. Over 3d, vibrations led to the greatest increase in total cell number with the frequency/acceleration combination that induced the smallest level of fluid shear. Acute experiments showed that actin remodeling was necessary for early mechanical up-regulation of RUNX-2 mRNA levels. During osteogenic differentiation, mechanically induced up-regulation of actin remodeling genes including Wiskott-Aldrich syndrome (WAS) protein, a critical regulator of Arp2/3 complex, was related to the magnitude of the applied acceleration but not to fluid shear. These data demonstrate that fluid shear does not regulate vibration induced proliferation and mineralization and that cytoskeletal remodeling activity may play a role in MSC mechanosensitivity.

  7. Disease Modification of Breast Cancer–Induced Bone Remodeling by Cannabinoid 2 Receptor Agonists

    PubMed Central

    Symons-Liguori, Ashley M; Largent-Milnes, Tally M; Havelin, Josh J; Ferland, Henry L; Chandramouli, Anupama; Owusu-Ankomah, Mabel; Nikolich-Zugich, Tijana; Bloom, Aaron P; Jimenez-Andrade, Juan Miguel; King, Tamara; Porreca, Frank; Nelson, Mark A; Mantyh, Patrick W; Vanderah, Todd W

    2015-01-01

    Most commonly originating from breast malignancies, metastatic bone cancer causes bone destruction and severe pain. Although novel chemotherapeutic agents have increased life expectancy, patients are experiencing higher incidences of fracture, pain, and drug-induced side effects; furthermore, recent findings suggest that patients are severely undertreated for their cancer pain. Strong analgesics, namely opiates, are first-line therapy in alleviating cancer-related pain despite the severe side effects, including enhanced bone destruction with sustained administration. Bone resorption is primarily treated with bisphosphonates, which are associated with highly undesirable side effects, including nephrotoxicity and osteonecrosis of the jaw. In contrast, cannabinoid receptor 2 (CB2) receptor-specific agonists have been shown to reduce bone loss and stimulate bone formation in a model of osteoporosis. CB2 agonists produce analgesia in both inflammatory and neuropathic pain models. Notably, mixed CB1/CB2 agonists also demonstrate a reduction in ErbB2-driven breast cancer progression. Here we demonstrate for the first time that CB2 agonists reduce breast cancer–induced bone pain, bone loss, and breast cancer proliferation via cytokine/chemokine suppression. Studies used the spontaneously-occurring murine mammary cell line (66.1) implanted into the femur intramedullary space; measurements of spontaneous pain, bone loss, and cancer proliferation were made. The systemic administration of a CB2 agonist, JWH015, for 7 days significantly attenuated bone remodeling, assuaged spontaneous pain, and decreased primary tumor burden. CB2-mediated effects in vivo were reversed by concurrent treatment with a CB2 antagonist/inverse agonist but not with a CB1 antagonist/inverse agonist. In vitro, JWH015 reduced cancer cell proliferation and inflammatory mediators that have been shown to promote pain, bone loss, and proliferation. Taken together, these results suggest CB2 agonists as a

  8. Aged Lymphatic Vessels and Mast Cells in Perilymphatic Tissues.

    PubMed

    Pal, Sarit; Meininger, Cynthia J; Gashev, Anatoliy A

    2017-05-03

    This review provides a comprehensive summary of research on aging-associated alterations in lymphatic vessels and mast cells in perilymphatic tissues. Aging alters structure (by increasing the size of zones with low muscle cell investiture), ultrastructure (through loss of the glycocalyx), and proteome composition with a concomitant increase in permeability of aged lymphatic vessels. The contractile function of aged lymphatic vessels is depleted with the abolished role of nitric oxide and an increased role of lymphatic-born histamine in flow-dependent regulation of lymphatic phasic contractions and tone. In addition, aging induces oxidative stress in lymphatic vessels and facilitates the spread of pathogens from these vessels into perilymphatic tissues. Aging causes the basal activation of perilymphatic mast cells, which, in turn, restricts recruitment/activation of immune cells in perilymphatic tissues. This aging-associated basal activation of mast cells limits proper functioning of the mast cell/histamine/NF-κB axis that is essential for the regulation of lymphatic vessel transport and barrier functions as well as for both the interaction and trafficking of immune cells near and within lymphatic collecting vessels. Cumulatively, these changes play important roles in the pathogenesis of alterations in inflammation and immunity associated with aging.

  9. Vascularization in tissue remodeling after rat hepatic necrosis induced by dimethylnitrosamine.

    PubMed

    Jin, Yu-Lan; Enzan, Hideaki; Kuroda, Naoto; Hayashi, Yoshihiro; Toi, Makoto; Miyazaki, Eriko; Hamauzu, Tadashi; Hiroi, Makoto; Guo, Li-Mei; Shen, Zhe-Shi; Saibara, Toshiji

    2006-03-01

    We observed postnecrotic tissue remodeling to examine vascularization in adult rat livers. Livers, bone marrow, and peripheral blood from rats at 24 h to 14 days after an injection of dimethylnitrosamine (DMN) were examined by light microscopic, immunohistochemical, and ultrastructural methods. Numerous ED-1 (a marker for rat monocytes/macrophages)-positive round mononuclear cells infiltrated in the necrotic areas at 36 h after DMN treatment. On day 5, when necrotic tissues were removed, some of the cells were transformed from round to spindle in shape. On day 7, these cells were contacted with residual reticulin fibers and became positive for SE-1, a marker of hepatic sinusoidal endothelial cells and Tie-1, an endothelial cell-specific surface receptor, associated with frequent occurrence of ED-1/SE-1 and ED-1/Tie-1 double-positive spindle cells. Ultrastructurally, the spindle cells simultaneously showed phagocytosis and endothelial cell-like morphology. With time necrotic areas diminished, and on day 14, the necrotic tissues were almost replaced by regenerated liver tissues and thin bundles of central-to-central bridging fibrosis. Bone marrow from 12 h to day 2 showed an increase of BrdU-positive mononuclear cells. Some of them were positive for ED-1. The BrdU-labeled and ED-1-positive cells appeared as early as 12 h after DMN injection and reached a peak in number at 36 h. They were similar in structure to ED-1-positive cells in necrotic liver tissues. These findings suggest that round mononuclear ED-1-positive cells proliferate first in bone marrow after DMN treatment, reach necrotic areas of the liver through the circulation, and differentiate to sinusoidal endothelial cells. Namely, hepatic sinusoids in DMN-induced necrotic areas may partly be reorganized possibly by vasculogenesis.

  10. Impact of bone marrow-derived mesenchymal stem cells on remodeling the lung injury induced by lipopolysaccharides in mice

    PubMed Central

    Mohi El-Din, Mouchira M; Rashed, Laila A; Mahmoud Haridy, Mohi A; Khalil, Atef Mohamed; Mohamed Albadry, Mohamed A

    2017-01-01

    Aim: This study evaluated the potential of bone marrow derived mesenchymal stem cells (MSCs) to regulate cytokines and remodel the lung induced by lipopolysaccharide (LPS; O-antigen). Materials & methods: A group of mice (n = 21) was inoculated intraperitoneally with one dose 0.1 ml containing 0.025 mg LPS/mouse, and another treated intravenously with one dose of labeling bone marrow derived MSCs at 7.5 × 105 cell/mouse 4 h after LPS injection. All animals were sacrificed on the 1st, 7th and 14th days post-injection. Results: MSCs increased the level of IL-10 with suppression of TNF-α, decrease of collagen fibers and renewal of alveolar type I cells, together with lung tissue remodeling. Conclusion: MSCs were shown to modulate inflammatory cytokines (TNF-α and IL-10) and to differentiate into alveolar type I cells, which prevented fibrosis in lung tissue from LPS-treated mice. PMID:28344826

  11. Experimental Myocardial Infarction Induces Altered Regulatory T Cell Hemostasis, and Adoptive Transfer Attenuates Subsequent Remodeling

    PubMed Central

    Sharir, Rinat; Semo, Jonathan; Shimoni, Sara; Ben-Mordechai, Tamar; Landa-Rouben, Natalie; Maysel-Auslender, Sofia; Shaish, Aviv; Entin–Meer, Michal; Keren, Gad; George, Jacob

    2014-01-01

    Background Ischemic cardiac damage is associated with upregulation of cardiac pro-inflammatory cytokines, as well as invasion of lymphocytes into the heart. Regulatory T cells (Tregs) are known to exert a suppressive effect on several immune cell types. We sought to determine whether the Treg pool is influenced by myocardial damage and whether Tregs transfer and deletion affect cardiac remodeling. Methods and Results The number and functional suppressive activity of Tregs were assayed in mice subjected to experimental myocardial infarction. The numbers of splenocyte-derived Tregs in the ischemic mice were significantly higher after the injury than in the controls, and their suppressive properties were significantly compromised. Compared with PBS, adoptive Treg transfer to mice with experimental infarction reduced infarct size and improved LV remodeling and functional performance by echocardiography. Treg deletion with blocking anti-CD25 antibodies did not influence infarct size or echocardiographic features of cardiac remodeling. Conclusion Treg numbers are increased whereas their function is compromised in mice with that underwent experimental infarction. Transfer of exogeneous Tregs results in attenuation of myocardial remodeling whereas their ablation has no effect. Thus, Tregs may serve as interesting potential interventional targets for attenuating left ventricular remodeling. PMID:25436994

  12. Loss of Progesterone Receptor-Mediated Actions Induce Preterm Cellular and Structural Remodeling of the Cervix and Premature Birth

    PubMed Central

    Yellon, Steven M.; Dobyns, Abigail E.; Beck, Hailey L.; Kurtzman, James T.; Garfield, Robert E.; Kirby, Michael A.

    2013-01-01

    A decline in serum progesterone or antagonism of progesterone receptor function results in preterm labor and birth. Whether characteristics of premature remodeling of the cervix after antiprogestins or ovariectomy are similar to that at term was the focus of the present study. Groups of pregnant rats were treated with vehicle, a progesterone receptor antagonist (onapristone or mifepristone), or ovariectomized on day 17 postbreeding. As expected, controls given vehicle delivered at term while rats delivered preterm after progesterone receptor antagonist treatment or ovariectomy. Similar to the cervix before term, the preterm cervix of progesterone receptor antagonist-treated rats was characterized by reduced cell nuclei density, decreased collagen content and structure, as well as a greater presence of macrophages per unit area. Thus, loss of nuclear progesterone receptor-mediated actions promoted structural remodeling of the cervix, increased census of resident macrophages, and preterm birth much like that found in the cervix at term. In contrast to the progesterone receptor antagonist-induced advance in characteristics associated with remodeling, ovariectomy-induced loss of systemic progesterone did not affect hypertrophy, extracellular collagen, or macrophage numbers in the cervix. Thus, the structure and macrophage census in the cervix appear sufficient for premature ripening and birth to occur well before term. With progesterone receptors predominantly localized on cells other than macrophages, the findings suggest that interactions between cells may facilitate the loss of progesterone receptor-mediated actions as part of a final common mechanism that remodels the cervix in certain etiologies of preterm and with parturition at term. PMID:24339918

  13. The MAPK pathway is involved in the regulation of rapid pacing-induced ionic channel remodeling in rat atrial myocytes.

    PubMed

    Cheng, Wei; Zhu, Yun; Wang, Haidong

    2016-03-01

    Alterations to the expression L‑type calcium channels (LTCCs) and Kv4.3 potassium channels form the possible basis of atrial electrical remodeling during rapid pacing. The mitogen‑activated protein kinase (MAPK) pathway is affected by increases in cytoplasmic Ca2+, and therefore represents an attractive candidate for the regulation and mediation of Ca2+‑induced ion channel remodeling. The present study aimed to investigate alterations to the ion channel‑MAPK axis, and to determine its influence on ion channel remodeling during atrial fibrillation. Rat atrial myocytes were isolated, cultured, and in vitro rapid pacing was established. Intracellular Ca2+ signals were monitored using the Fluo‑3/AM Ca2+ indicator. Verapamil, PD98058 and SB203580 were added to the culture medium of various groups at specific time‑points. The mRNA expression levels of LTCC‑α1c and Kv4.3 potassium channels were detected by reverse transcription‑polymerase chain reaction. Western blotting was performed to determine the expression levels of channel and signaling proteins. The results demonstrated that fast pacing significantly increased the intracellular Ca2+ concentration in atrial myocytes, whereas treatment with verapamil markedly inhibited this increase. In addition, verapamil significantly antagonized the rapid pacing‑induced activation of extracellular signal‑regulated kinase (ERK) and p38MAPK. These results indicated that the MAPK pathway may have an important role in the opening of LTCCs, and alterations to MAPK molecule expression could affect the expression and remodeling of ion channels.

  14. Anti-inflammatory, Antithrombotic and Cardiac Remodeling Preventive Effects of Eugenol in Isoproterenol-Induced Myocardial Infarction in Wistar Rat.

    PubMed

    Mnafgui, Kais; Hajji, Raouf; Derbali, Fatma; Gammoudi, Anis; Khabbabi, Gaddour; Ellefi, Hedi; Allouche, Noureddine; Kadri, Adel; Gharsallah, Neji

    2016-10-01

    This study aimed to evaluate the antithrombotic, anti-inflammatory and anti-cardiac remodeling properties of eugenol in isoproterenol-induced myocardial infarction in rats. Male Wistar rats were randomly divided into four groups, control, iso [100 mg/kg body weight was injected subcutaneously into rats at an interval of 24 h for 2 days (6th and 7th day) to induce MI] and pretreated animals with clopidogrel (0.2 mg/kg) and eugenol (50 mg/kg) orally for 7 days and intoxicated with isoproterenol (Iso + Clop) and (Iso + EG) groups. Isoproterenol-induced myocardial infarcted rats showed notable changes in the ECG pattern, increase in heart weight index, deterioration in the hemodynamic function and rise in plasma level of troponin-T, CK-MB and LDH and ALT by 316, 74, 172 and 45 %, respectively, with histological myocardium necrosis and cells inflammatory infiltration. In addition, significant increases in plasma levels of inflammatory biomarkers such as fibrinogen, α1, α2, β1, β2 and γ globulins with decrease level of albumin were observed in infarcted rats as compared to normal ones. Else, the angiotensin-converting enzyme (ACE) activity in plasma, kidney and heart of the isoproterenol-induced rats was significantly increased by 34, 47 and 93 %, respectively, as compared to normal group. However, the administration of eugenol induced a clear improvement in cardiac biomarkers injury, reduced inflammatory mediators proteins, increased heart activities of superoxide dismutase and glutathione peroxidase with reduce in thiobarbituric acid-reactive substances content and inhibition of ventricular remodeling process through inhibition of ACE activity. Overall, eugenol evidences high preventive effects from cardiac remodeling process.

  15. AAV Delivery of TNF-α shRNA Attenuates Cold-induced Pulmonary Hypertension and Pulmonary Arterial Remodeling

    PubMed Central

    Crosswhite, Patrick; Chen, Kai; Sun, Zhongjie

    2014-01-01

    Cold temperatures are associated with increased mortality and morbidity of cardiovascular and pulmonary disease. Cold exposure causes lung inflammation, pulmonary hypertension (PH) and right ventricle (RV) hypertrophy, but there is no effective therapy due to unknown mechanism. Here we investigated if RNAi silencing of TNF-α decreases cold-induced macrophage infiltration, PH, and pulmonary arterial (PA) remodeling. We found for the first time that continuous cold exposure (5.0°C) increased TNF-α expression and macrophage infiltration in the lungs and pulmonary arteries (PAs) right before elevation of RV systolic pressure. The in vivo RNAi silencing of TNF-α was achieved by IV delivery of recombinant AAV-2 carrying TNFα short hairpin siRNA (TNFshRNA) 24 hours prior to cold exposure. Cold exposure for eight weeks significantly increased RV pressure compared to the warm controls (40.19±4.9 vs. 22.9±1.1 mmHg), indicating that cold exposure caused PH. Cold exposure increased TNF-α, IL-6 and phosphodierterase-1C (PDE-1C) protein expression in the lungs and PAs and increased lung macrophage infiltration. Notably, TNFshRNA prevented the cold-induced increases in TNF-α, IL-6 and PDE-1C protein expression, abolished lung macrophage infiltration, and attenuated PH (26.28±1.6 mmHg), PA remodeling, and RV hypertrophy. PA SMCs isolated from cold-exposed animals showed increased intracellular superoxide levels and cell proliferation along with decreased intracellular cGMP. These cold-induced changes were prevented by TNFshRNA. Conclusions Upregulation of TNF-α played a critical role in the pathogenesis of cold-induced PH by promoting pulmonary macrophage infiltration and inflammation. AAV delivery of TNFshRNA may be an effective therapeutic approach for cold-induced PH and PA remodeling. PMID:25185133

  16. Orphan Nuclear Receptor Nur77 Inhibits Angiotensin II-Induced Vascular Remodeling via Downregulation of β-Catenin.

    PubMed

    Cui, Mingli; Cai, Zhaohua; Chu, Shichun; Sun, Zhe; Wang, Xiaolei; Hu, Liuhua; Yi, Jing; Shen, Linghong; He, Ben

    2016-01-01

    Angiotensin II (Ang II) is the predominant effector peptide of the renin-angiotensin system. Ang II contributes to vascular remodeling in many cardiovascular diseases (eg, hypertension, atherosclerosis, restenosis, and aneurysm). Orphan nuclear receptor Nur77 has a crucial role in the functional regulation of vascular cells. The objective of this study was to define the specific role of Nur77 in Ang II-induced vascular remodeling. Nur77 expression was initially found to be elevated in medial vascular smooth muscle cells (VSMCs) of thoracic aortas from mice continuously infused with Ang II for 2 weeks using a subcutaneous osmotic minipump. Cellular studies revealed that Nur77 expression was upregulated by Ang II via the MAPK/PKA-CREB signaling pathway. Ang II-induced proliferation, migration, and phenotypic switching were significantly enhanced in VSMCs isolated from Nur77(-/-) mice compared with wild-type VSMCs. Consistent with the role in VSMCs, we found that compared with wild-type mice, Nur77(-/-) mice had elevated aortic medial areas and luminal diameters, more severe elastin disruption and collagen deposition, increased VSMC proliferation and matrix metalloproteinase production, and decreased VSMC-specific genes SM-22α and α-actin expression, after 2 weeks of exogenous Ang II administration. The results of additional experiments suggested that Nur77 suppressed Ang II-induced β-catenin signaling pathway activation by promoting β-catenin degradation and inhibiting its transcriptional activity. Our findings indicated that Nur77 is a critical negative regulator of Ang II-induced VSMC proliferation, migration, and phenotypic switching via the downregulation of β-catenin activity. Nur77 may reduce Ang II-induced vascular remodeling involved in many cardiovascular diseases. © 2015 American Heart Association, Inc.

  17. Viral infection of the marine alga Emiliania huxleyi triggers lipidome remodeling and induces the production of highly saturated triacylglycerol.

    PubMed

    Malitsky, Sergey; Ziv, Carmit; Rosenwasser, Shilo; Zheng, Shuning; Schatz, Daniella; Porat, Ziv; Ben-Dor, Shifra; Aharoni, Asaph; Vardi, Assaf

    2016-04-01

    Viruses that infect marine photosynthetic microorganisms are major ecological and evolutionary drivers of microbial food webs, estimated to turn over more than a quarter of the total photosynthetically fixed carbon. Viral infection of the bloom-forming microalga Emiliania huxleyi induces the rapid remodeling of host primary metabolism, targeted towards fatty acid metabolism. We applied a liquid chromatography-mass spectrometry (LC-MS)-based lipidomics approach combined with imaging flow cytometry and gene expression profiling to explore the impact of viral-induced metabolic reprogramming on lipid composition. Lytic viral infection led to remodeling of the cellular lipidome, by predominantly inducing the biosynthesis of highly saturated triacylglycerols (TAGs), coupled with a significant accumulation of neutral lipids within lipid droplets. Furthermore, TAGs were found to be a major component (77%) of the lipidome of isolated virions. Interestingly, viral-induced TAGs were significantly more saturated than TAGs produced under nitrogen starvation. This study highlights TAGs as major products of the viral-induced metabolic reprogramming during the host-virus interaction and indicates a selective mode of membrane recruitment during viral assembly, possibly by budding of the virus from specialized subcellular compartments. These findings provide novel insights into the role of viruses infecting microalgae in regulating metabolism and energy transfer in the marine environment and suggest their possible biotechnological application in biofuel production.

  18. Allergen-induced airway remodeling is impaired in galectin-3 deficient mice1

    PubMed Central

    Ge, Xiao Na; Bahaie, Nooshin S.; Kang, Bit Na; Hosseinkhani, Reza M.; Ha, Sung Gil; Frenzel, Elizabeth M.; Liu, Fu-Tong; Rao, Savita P.; Sriramarao, P.

    2010-01-01

    The role played by the β-galactoside-binding lectin galectin-3 (Gal-3) in airway remodeling, a characteristic feature of asthma that leads to airway dysfunction and poor clinical outcome in humans, was investigated in a murine model of chronic allergic airway inflammation. Wild-type (WT) and Gal-3 knock-out (KO) mice were subjected to repetitive allergen challenge with ovalbumin (OVA) up to 12 weeks and bronchoalveolar lavage fluid (BALF) and lung tissue collected after the last challenge were evaluated for cellular features associated with airway remodeling. Compared to WT mice, chronic OVA challenge in Gal-3 KO mice resulted in diminished remodeling of the airways with significantly reduced mucus secretion, sub-epithelial fibrosis, smooth muscle thickness, and peribronchial angiogenesis. The higher degree of airway remodeling in WT mice was associated with higher Gal-3 expression in the BALF as well as lung tissue. Cell counts in BALF and lung immunohistology demonstrated that eosinophil infiltration in OVA-challenged Gal-3 KO mice was significantly reduced compared to WT mice. Evaluation of cellular mediators associated with eosinophil recruitment and airway remodeling revealed that levels of eotaxin-1, IL-5, IL-13, FIZZ1 and TGF-β were substantially lower in Gal-3 KO mice. Finally, leukocytes from Gal-3 KO mice demonstrated decreased trafficking (rolling) on vascular endothelial adhesion molecules compared to WT cells. Overall, these studies demonstrate that Gal-3 is an important lectin that promotes airway remodeling via airway recruitment of inflammatory cells, specifically eosinophils, and the development of a Th2 phenotype as well as increased expression of eosinophil-specific chemokines, pro-fibrogenic and angiogenic mediators. PMID:20543100

  19. α-Synuclein Senses Lipid Packing Defects and Induces Lateral Expansion of Lipids Leading to Membrane Remodeling*

    PubMed Central

    Ouberai, Myriam M.; Wang, Juan; Swann, Marcus J.; Galvagnion, Celine; Guilliams, Tim; Dobson, Christopher M.; Welland, Mark E.

    2013-01-01

    There is increasing evidence for the involvement of lipid membranes in both the functional and pathological properties of α-synuclein (α-Syn). Despite many investigations to characterize the binding of α-Syn to membranes, there is still a lack of understanding of the binding mode linking the properties of lipid membranes to α-Syn insertion into these dynamic structures. Using a combination of an optical biosensing technique and in situ atomic force microscopy, we show that the binding strength of α-Syn is related to the specificity of the lipid environment (the lipid chemistry and steric properties within a bilayer structure) and to the ability of the membranes to accommodate and remodel upon the interaction of α-Syn with lipid membranes. We show that this interaction results in the insertion of α-Syn into the region of the headgroups, inducing a lateral expansion of lipid molecules that can progress to further bilayer remodeling, such as membrane thinning and expansion of lipids out of the membrane plane. We provide new insights into the affinity of α-Syn for lipid packing defects found in vesicles of high curvature and in planar membranes with cone-shaped lipids and suggest a comprehensive model of the interaction between α-Syn and lipid bilayers. The ability of α-Syn to sense lipid packing defects and to remodel membrane structure supports its proposed role in vesicle trafficking. PMID:23740253

  20. Long-Term Effects of Chromatin Remodeling and DNA Damage in Stem Cells Induced by Environmental and Dietary Agents

    PubMed Central

    Bariar, Bhawana; Vestal, C. Greer; Richardson, Christine

    2014-01-01

    The presence of histones acts as a barrier to protein access; thus chromatin remodeling must occur for essential processes such as transcription and replication. In conjunction with histone modifications, DNA methylation plays critical roles in gene silencing through chromatin remodeling. Chromatin remodeling is also interconnected with the DNA damage response, maintenance of stem cell properties, and cell differentiation programs. Chromatin modifications have increasingly been shown to produce long-lasting alterations in chromatin structure and transcription. Recent studies have shown environmental exposures in utero have the potential to alter normal developmental signaling networks, physiologic responses, and disease susceptibility later in life during a process known as developmental reprogramming. In this review we discuss the long-term impact of exposure to environmental compounds, the chromatin modifications that they induce, and the differentiation and developmental programs of multiple stem and progenitor cell types altered by exposure. The main focus is to highlight agents present in the human lifestyle that have the potential to promote epigenetic changes that impact developmental programs of specific cell types, may promote tumorigenesis through altering epigenetic marks, and may be transgenerational, for example, those able to be transmitted through multiple cell divisions. PMID:24579784

  1. Role of Hyperplasia of Gingival Lymphatics in Periodontal Inflammation.

    PubMed

    Papadakou, P; Bletsa, A; Yassin, M A; Karlsen, T V; Wiig, H; Berggreen, E

    2017-04-01

    Lymphatic vessels are important for maintenance of tissue fluid homeostasis and afferent antigen transport. In chronic inflammation, lymphangiogenesis takes place and is characterized by lymphatic endothelial cell proliferation and lymphatic hyperplasia. Vascular endothelial growth factor C (VEGFC) is the main known lymphangiogenic growth factor, and its expression is increased in periodontitis, a common chronic infectious disease that results in tissue destruction and alveolar bone loss. The role of lymphangiogenesis during development of periodontitis is unknown. Here, we test if transgenic overexpression of epithelial VEGFC in a murine model is followed by hyperplasia of lymphatic vessels in oral mucosa and if the lymphatic drainage capacity is altered. We also test if lymphatic hyperplasia protects against periodontal disease development. Transgenic keratin 14 (K14)-VEGFC mice had significant hyperplasia of lymphatics in oral mucosa, including gingiva, without changes in blood vessel vasculature. The basal lymph flow was normal but slightly lower than in wild-type mice when oral mucosa was challenged with lipopolysaccharide from Porphyromonas gingivalis. Under normal conditions, K14-VEGFC mice exhibited an increased number of neutrophils in gingiva, demonstrated enhanced phagocyte recruitment in the cervical lymph nodes, and had more alveolar bone when compared with their wild-type littermates. After induction of periodontitis, no strain differences were observed in the periodontal tissues with respect to granulocyte recruitment, bone resorption, angiogenesis, cytokines, and bone-related protein expressions or in draining lymph node immune cell proportions and vascularization. We conclude that overexpression of VEGFC results in hyperplastic lymphatics, which do not enhance lymphatic drainage capacity but facilitate phagocyte transport to draining lymph nodes. Hyperplasia of lymphatics does not protect against development of ligature-induced periodontitis.

  2. Mesoscale computational studies of membrane bilayer remodeling by curvature-inducing proteins

    NASA Astrophysics Data System (ADS)

    Ramakrishnan, N.; Sunil Kumar, P. B.; Radhakrishnan, Ravi

    2014-10-01

    Biological membranes constitute boundaries of cells and cell organelles. These membranes are soft fluid interfaces whose thermodynamic states are dictated by bending moduli, induced curvature fields, and thermal fluctuations. Recently, there has been a flood of experimental evidence highlighting active roles for these structures in many cellular processes ranging from trafficking of cargo to cell motility. It is believed that the local membrane curvature, which is continuously altered due to its interactions with myriad proteins and other macromolecules attached to its surface, holds the key to the emergent functionality in these cellular processes. Mechanisms at the atomic scale are dictated by protein-lipid interaction strength, lipid composition, lipid distribution in the vicinity of the protein, shape and amino acid composition of the protein, and its amino acid contents. The specificity of molecular interactions together with the cooperativity of multiple proteins induce and stabilize complex membrane shapes at the mesoscale. These shapes span a wide spectrum ranging from the spherical plasma membrane to the complex cisternae of the Golgi apparatus. Mapping the relation between the protein-induced deformations at the molecular scale and the resulting mesoscale morphologies is key to bridging cellular experiments across various length scales. In this review, we focus on the theoretical and computational methods used to understand the phenomenology underlying protein-driven membrane remodeling. Interactions at the molecular scale can be computationally probed by all atom and coarse grained molecular dynamics (MD, CGMD), as well as dissipative particle dynamics (DPD) simulations, which we only describe in passing. We choose to focus on several continuum approaches extending the Canham-Helfrich elastic energy model for membranes to include the effect of curvature-inducing proteins and explore the conformational phase space of such systems. In this description, the

  3. Mesoscale computational studies of membrane bilayer remodeling by curvature-inducing proteins

    PubMed Central

    Ramakrishnan, N.; Sunil Kumar, P. B.; Radhakrishnan, Ravi

    2014-01-01

    Biological membranes constitute boundaries of cells and cell organelles. These membranes are soft fluid interfaces whose thermodynamic states are dictated by bending moduli, induced curvature fields, and thermal fluctuations. Recently, there has been a flood of experimental evidence highlighting active roles for these structures in many cellular processes ranging from trafficking of cargo to cell motility. It is believed that the local membrane curvature, which is continuously altered due to its interactions with myriad proteins and other macromolecules attached to its surface, holds the key to the emergent functionality in these cellular processes. Mechanisms at the atomic scale are dictated by protein-lipid interaction strength, lipid composition, lipid distribution in the vicinity of the protein, shape and amino acid composition of the protein, and its amino acid contents. The specificity of molecular interactions together with the cooperativity of multiple proteins induce and stabilize complex membrane shapes at the mesoscale. These shapes span a wide spectrum ranging from the spherical plasma membrane to the complex cisternae of the Golgi apparatus. Mapping the relation between the protein-induced deformations at the molecular scale and the resulting mesoscale morphologies is key to bridging cellular experiments across the various length scales. In this review, we focus on the theoretical and computational methods used to understand the phenomenology underlying protein-driven membrane remodeling. Interactions at the molecular scale can be computationally probed by all atom and coarse grained molecular dynamics (MD, CGMD), as well as dissipative particle dynamics (DPD) simulations, which we only describe in passing. We choose to focus on several continuum approaches extending the Canham - Helfrich elastic energy model for membranes to include the effect of curvature-inducing proteins and explore the conformational phase space of such systems. In this

  4. Mesoscale computational studies of membrane bilayer remodeling by curvature-inducing proteins.

    PubMed

    Ramakrishnan, N; Sunil Kumar, P B; Radhakrishnan, Ravi

    2014-10-01

    Biological membranes constitute boundaries of cells and cell organelles. These membranes are soft fluid interfaces whose thermodynamic states are dictated by bending moduli, induced curvature fields, and thermal fluctuations. Recently, there has been a flood of experimental evidence highlighting active roles for these structures in many cellular processes ranging from trafficking of cargo to cell motility. It is believed that the local membrane curvature, which is continuously altered due to its interactions with myriad proteins and other macromolecules attached to its surface, holds the key to the emergent functionality in these cellular processes. Mechanisms at the atomic scale are dictated by protein-lipid interaction strength, lipid composition, lipid distribution in the vicinity of the protein, shape and amino acid composition of the protein, and its amino acid contents. The specificity of molecular interactions together with the cooperativity of multiple proteins induce and stabilize complex membrane shapes at the mesoscale. These shapes span a wide spectrum ranging from the spherical plasma membrane to the complex cisternae of the Golgi apparatus. Mapping the relation between the protein-induced deformations at the molecular scale and the resulting mesoscale morphologies is key to bridging cellular experiments across the various length scales. In this review, we focus on the theoretical and computational methods used to understand the phenomenology underlying protein-driven membrane remodeling. Interactions at the molecular scale can be computationally probed by all atom and coarse grained molecular dynamics (MD, CGMD), as well as dissipative particle dynamics (DPD) simulations, which we only describe in passing. We choose to focus on several continuum approaches extending the Canham - Helfrich elastic energy model for membranes to include the effect of curvature-inducing proteins and explore the conformational phase space of such systems. In this

  5. Arginase inhibition prevents bleomycin-induced pulmonary hypertension, vascular remodeling, and collagen deposition in neonatal rat lungs.

    PubMed

    Grasemann, Hartmut; Dhaliwal, Rupinder; Ivanovska, Julijana; Kantores, Crystal; McNamara, Patrick J; Scott, Jeremy A; Belik, Jaques; Jankov, Robert P

    2015-03-15

    Arginase is an enzyme that limits substrate L-arginine bioavailability for the production of nitric oxide by the nitric oxide synthases and produces L-ornithine, which is a precursor for collagen formation and tissue remodeling. We studied the pulmonary vascular effects of arginase inhibition in an established model of repeated systemic bleomycin sulfate administration in neonatal rats that results in pulmonary hypertension and lung injury mimicking the characteristics typical of bronchopulmonary dysplasia. We report that arginase expression is increased in the lungs of bleomycin-exposed neonatal rats and that treatment with the arginase inhibitor amino-2-borono-6-hexanoic acid prevented the bleomycin-induced development of pulmonary hypertension and deposition of collagen. Arginase inhibition resulted in increased L-arginine and L-arginine bioavailability and increased pulmonary nitric oxide production. Arginase inhibition also normalized the expression of inducible nitric oxide synthase, and reduced bleomycin-induced nitrative stress while having no effect on bleomycin-induced inflammation. Our data suggest that arginase is a promising target for therapeutic interventions in neonates aimed at preventing lung vascular remodeling and pulmonary hypertension.

  6. Bone remodelling in the natural acetabulum is influenced by muscle force-induced bone stress.

    PubMed

    Fernandez, Justin; Sartori, Massimo; Lloyd, David; Munro, Jacob; Shim, Vickie

    2014-01-01

    A modelling framework using the international Physiome Project is presented for evaluating the role of muscles on acetabular stress patterns in the natural hip. The novel developments include the following: (i) an efficient method for model generation with validation; (ii) the inclusion of electromyography-estimated muscle forces from gait; and (iii) the role that muscles play in the hip stress pattern. The 3D finite element hip model includes anatomically based muscle area attachments, material properties derived from Hounsfield units and validation against an Instron compression test. The primary outcome from this study is that hip loading applied as anatomically accurate muscle forces redistributes the stress pattern and reduces peak stress throughout the pelvis and within the acetabulum compared with applying the same net hip force without muscles through the femur. Muscle forces also increased stress where large muscles have small insertion sites. This has implications for the hip where bone stress and strain are key excitation variables used to initiate bone remodelling based on the strain-based bone remodelling theory. Inclusion of muscle forces reduces the predicted sites and degree of remodelling. The secondary outcome is that the key muscles that influenced remodelling in the acetabulum were the rectus femoris, adductor magnus and iliacus. Copyright © 2013 John Wiley & Sons, Ltd.

  7. Mechanism of Tissue Remodeling in Sepsis-Induced Acute Lung Injury

    DTIC Science & Technology

    2005-04-01

    acute lung injury have been identified (e.g., infection, trauma ), little is known about the factors that control the tissue remodeling response. This...in fibroblasts. This suggests that the main player in this process is acetaldehyde . To test this, we exposed cells to acetaldehyde and found that this

  8. Microdamage induced by in vivo Reference Point Indentation in mice is repaired by osteocyte-apoptosis mediated remodeling.

    PubMed

    Kennedy, Oran D; Lendhey, Matin; Mauer, Peter; Philip, Anaya; Basta-Pljakic, Jelena; Schaffler, Mitchell B

    2017-02-01

    Reference Point Indentation (RPI) is a technology that is designed to measure mechanical properties that relate to bone toughness, or its ability to resist crack growth, in vivo. Independent of the mechanical parameters generated by RPI, its ability to initiate and propagate microcracks in bone is itself an interesting issue. Microcracks have a crucial biological relevance in bone, are central to its ability to maintain homeostasis. In healthy tissues, a process of targeted remodeling routinely repairs microcracks in a process mediated by osteocyte apoptosis. However, in diseases such as osteoporosis this process becomes deficient and microcracks can accumulate. Small animal models such are crucial for the study of such diseases, but it is technically challenging to create microcracks in these animals without causing outright failure. Therefore we sought to use RPI as a focal microdamage placement tool, to introduce microcracks to mouse long bones and investigate whether the same pathway mediates their repair as that described in other microdamage systems. We first used SEM to confirm that microdamage is formed RPI in mouse bone. Then, since RPI is carried out transdermally, we sought to confirm that no periosteal response occurred at the indented region. We then used a pan-caspase inhibitor (QVD) to determine whether osteocyte apoptosis plays the same pivotal role in microdamage repair in this model, as has been demonstrated in others. In conclusion, we validated that the microdamage-apoptosis-remodeling pathway is maintained with this method of microdamage induction in mice. We show that RPI can be used as a reliable and reproducible microdamage placement tool in living mouse long bones without inducing a periosteal response. We also used a caspase inhibitor, to block osteocyte apoptosis and thus abrogate the remodeling response to microdamage. This demonstrates that the well described microdamage repair system, involving targeted remodeling mediated by osteocyte

  9. INDUCED REMODELING OF PORCINE TENDONS TO HUMAN ANTERIOR CRUCIATE LIGAMENTS BY α-GAL EPITOPE REMOVAL AND PARTIAL CROSSLINKING.

    PubMed

    Stone, Kevin Robert; Walgenbach, Ann; Galili, Uri

    2017-01-09

    This review describes a novel method developed for processing porcine tendon and other ligament implants which enables in situ remodeling into autologous ligaments in humans. The method differs from methods using extracellular matrices (ECM) which provide post-operative ortho-biologic support (i.e. augmentation grafts) for healing of injured ligaments, in that the porcine bone-patellar-tendon-bone itself serves as the graft replacing ruptured anterior cruciate ligament (ACL). The method allows for gradual remodeling of porcine tendon into autologous human ACL while maintaining the biomechanical integrity. The method was first evaluated in a pre-clinical model of monkeys and subsequently in patients. The method overcomes detrimental effects of the natural anti-Gal antibody and harnesses anti-non gal antibodies for the remodeling process in two steps: Step 1. Elimination of α-gal epitopes- This epitope which is abundant in pigs (as in other non-primate mammals) binds the natural anti-Gal antibody which is the most abundant natural antibody in humans. This interaction, which can induce fast resorption of the porcine implant, is avoided by enzymatic elimination of α-gal epitopes from the implant with recombinant α-galactosidase. Step 2. Partial crosslinking of porcine tendon with glutaraldehyde- This crosslinking generates covalent bonds in the ECM which slow infiltration of macrophages into the implant. Anti-non gal antibodies are produced in recipients against the multiple porcine antigenic proteins and proteoglycans because of sequence differences between human and porcine homologous proteins. Anti-non gal antibodies bind to the implant ECM, recruit macrophages and induce the implant destruction by directing proteolytic activity of macrophages. Partial crosslinking of the tendon ECM decreases the extent of macrophage infiltration and degradation of the implant and enables concomitant infiltration of fibroblasts which follow the infiltrating macrophages. These

  10. Immunolocalization of lymphatic vessels in human fetal knee joint tissues.

    PubMed

    Melrose, James; Little, Christopher B

    2010-08-01

    We immunolocalized lymphatic and vascular blood vessels in 12- and 14-week-old human fetal knee joint tissues using a polyclonal antibody to a lymphatic vascular endothelium specific hyaluronan receptor (LYVE-1) and a monoclonal antibody to podoplanin (mAb D2-40). A number of lymphatic vessels were identified in the stratified connective tissues surrounding the cartilaginous knee joint femoral and tibial rudiments. These tissues also contained small vascular vessels with entrapped red blood cells which were imaged using Nomarsky DIC microscopy. Neither vascular nor lymphatic vessels were present in the knee joint cartilaginous rudiments. The menisci in 12-week-old fetal knees were incompletely demarcated from the adjacent tibial and femoral cartilaginous rudiments which was consistent with the ongoing joint cavitation process at the femoral-tibial junction. At 14 weeks of age the menisci were independent structural entities; they contained a major central blood vessel containing red blood cells and numerous communicating vessels at the base of the menisci but no lymphatic vessels. In contrast to the 12-week-old menisci, the 14-week meniscal rudiments contained abundant CD-31 and CD-34 positive but no lymphatic vessels. Isolated 14-week-old meniscal cells also were stained with the CD-31 and CD 34 antibodies; CD-68 +ve cells, also abundant in the 14-week-old menisci, were detectable to a far lesser degree in the 12-week menisci and were totally absent from the femoral and tibial rudiments. The distribution of lymphatic vessels and tissue macrophages in the fetal joint tissues was consistent with their roles in the clearance of metabolic waste and extracellular matrix breakdown products arising from the rapidly remodelling knee joint tissues.

  11. Lymphatic Vessels, Inflammation, and Immunity in Skin Cancer

    PubMed Central

    Lund, Amanda W.; Medler, Terry R.; Leachman, Sancy A.; Coussens, Lisa M.

    2015-01-01

    Skin is a highly ordered immune organ that coordinates rapid responses to external insult while maintaining self-tolerance. In healthy tissue, lymphatic vessels drain fluid and coordinate local immune responses; however, environmental factors induce lymphatic vessel dysfunction, leading to lymph stasis and perturbed regional immunity. These same environmental factors drive the formation of local malignancies, which are also influenced by local inflammation. Herein, we discuss clinical and experimental evidence supporting the tenet that lymphatic vessels participate in regulation of cutaneous inflammation and immunity, are important contributors to malignancy and potential biomarkers and targets for immunotherapy. PMID:26552413

  12. Lymphatic filariasis and onchocerciasis.

    PubMed

    Taylor, Mark J; Hoerauf, Achim; Bockarie, Moses

    2010-10-02

    Lymphatic filariasis and onchocerciasis are parasitic helminth diseases that constitute a serious public health issue in tropical regions. The filarial nematodes that cause these diseases are transmitted by blood-feeding insects and produce chronic and long-term infection through suppression of host immunity. Disease pathogenesis is linked to host inflammation invoked by the death of the parasite, causing hydrocoele, lymphoedema, and elephantiasis in lymphatic filariasis, and skin disease and blindness in onchocerciasis. Most filarial species that infect people co-exist in mutualistic symbiosis with Wolbachia bacteria, which are essential for growth, development, and survival of their nematode hosts. These endosymbionts contribute to inflammatory disease pathogenesis and are a target for doxycycline therapy, which delivers macrofilaricidal activity, improves pathological outcomes, and is effective as monotherapy. Drugs to treat filariasis include diethylcarbamazine, ivermectin, and albendazole, which are used mostly in combination to reduce microfilariae in blood (lymphatic filariasis) and skin (onchocerciasis). Global programmes for control and elimination have been developed to provide sustained delivery of drugs to affected communities to interrupt transmission of disease and ultimately eliminate this burden on public health. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Preliminary evidence of the presence of lymphatic vessels immunoreactive for D2-40 and Prox-1 in human pterygium.

    PubMed

    Cimpean, Anca Maria; Poenaru Sava, Mihai; Raica, Marius; Ribatti, Domenico

    2011-11-01

    Human pterygium is a benign fibrovascular outgrowth of the corneo-conjunctival junction, characterized by tissue remodeling, cellular proliferation, angiogenesis and inflammation. No data are available concerning the presence of lymphatic vessels in this pathological condition. The aim of this study was to evaluate by immunohistochemistry, using antibodies against D2-40, Prox-1 and Ki-67, the presence and the proliferative activity of lymphatic vessels in human pterygium. An increased lymphatic microvessel density was observed in the human pterygium compared to the normal conjunctiva. Moreover, D2-40-positive lymphatic endothelial cells were also actively proliferating, as assessed by Ki-67 immunostaining, while in normal conjunctiva proliferating lymphatic endothelial cells were not detectable. Overall, these data clearly indicate the presence of active proliferating lymphatic vessels in human pterygium, suggesting that active lymphangiogenesis occurs in this pathological condition.

  14. The lymphatic vasculature in disease.

    PubMed

    Alitalo, Kari

    2011-11-07

    Blood vessels form a closed circulatory system, whereas lymphatic vessels form a one-way conduit for tissue fluid and leukocytes. In most vertebrates, the main function of lymphatic vessels is to collect excess protein-rich fluid that has extravasated from blood vessels and transport it back into the blood circulation. Lymphatic vessels have an important immune surveillance function, as they import various antigens and activated antigen-presenting cells into the lymph nodes and export immune effector cells and humoral response factors into the blood circulation. Defects in lymphatic function can lead to lymph accumulation in tissues, dampened immune responses, connective tissue and fat accumulation, and tissue swelling known as lymphedema. This review highlights the most recent developments in lymphatic biology and how the lymphatic system contributes to the pathogenesis of various diseases involving immune and inflammatory responses and its role in disseminating tumor cells.

  15. Temporal Dynamics of Acute Stress-Induced Dendritic Remodeling in Medial Prefrontal Cortex and the Protective Effect of Desipramine.

    PubMed

    Nava, Nicoletta; Treccani, Giulia; Alabsi, Abdelrahman; Kaastrup Mueller, Heidi; Elfving, Betina; Popoli, Maurizio; Wegener, Gregers; Nyengaard, Jens Randel

    2015-11-01

    Stressful events are associated with increased risk of mood disorders. Volumetric reductions have been reported in brain areas critical for the stress response, such as medial prefrontal cortex (mPFC), and dendritic remodeling has been proposed as an underlying factor. Here, we investigated the time-dependent effects of acute stress on dendritic remodeling within the prelimbic (PL) region of the PFC, and whether treatment with the antidepressant desipramine (DMI) may interfere. Rodents were subjected to foot-shock stress: dendritic length and spine density were analyzed 1 day, 7 days, and 14 days after stress. Acute stress produced increased spine density and decreased cofilin phosphorylation at 1 day, paralleled with dendritic retraction. An overall shift in spine population was observed at 1 day, resulting in a stress-induced increase in small spines. Significant atrophy of apical dendrites was observed at 1 day, which was prevented by chronic DMI, and at 14 days after stress exposure. Chronic DMI resulted in dendritic elaboration at 7 days but did not prevent the effects of FS-stress. Collectively, these data demonstrate that 1) acute stressors may induce rapid and sustained changes of PL neurons; and 2) chronic DMI may protect neurons from rapid stress-induced synaptic changes.

  16. Interaction of tumor cells and lymphatic vessels in cancer progression.

    PubMed

    Alitalo, A; Detmar, M

    2012-10-18

    Metastatic spread of cancer through the lymphatic system affects hundreds of thousands of patients yearly. Growth of new lymphatic vessels, lymphangiogenesis, is activated in cancer and inflammation, but is largely inactive in normal physiology, and therefore offers therapeutic potential. Key mediators of lymphangiogenesis have been identified in developmental studies. During embryonic development, lymphatic endothelial cells derive from the blood vascular endothelium and differentiate under the guidance of lymphatic-specific regulators, such as the prospero homeobox 1 transcription factor. Vascular endothelial growth factor-C (VEGF-C) and VEGF receptor 3 signaling are essential for the further development of lymphatic vessels and therefore they provide a promising target for inhibition of tumor lymphangiogenesis. Lymphangiogenesis is important for the progression of solid tumors as shown for melanoma and breast cancer. Tumor cells may use chemokine gradients as guidance cues and enter lymphatic vessels through intercellular openings between endothelial cell junctions or, possibly, by inducing larger discontinuities in the endothelial cell layer. Tumor-draining sentinel lymph nodes show enhanced lymphangiogenesis even before cancer metastasis and they may function as a permissive 'lymphovascular niche' for the survival of metastatic cells. Although our current knowledge indicates that the development of anti-lymphangiogenic therapies may be beneficial for the treatment of cancer patients, several open questions remain with regard to the frequency, mechanisms and biological importance of lymphatic metastases.

  17. Itching for answers: how histamine relaxes lymphatic vessels.

    PubMed

    Scallan, Joshua P; Davis, Michael J

    2014-10-01

    In the current issue of Microcirculation, studies by Kurtz et al. and Nizamutdinova et al. together provide new evidence supporting a role for histamine as an endothelial-derived molecule that inhibits lymphatic muscle contraction. In particular, Nizamutdinova et al. show that the effects of flow-induced shear stress on lymphatic endothelium are mediated by both nitric oxide and histamine, since only blockade of both prevents contraction strength and frequency from being altered by flow. Separately, Kurtz et al. used confocal microscopy to determine a preferential expression of histamine receptors on the lymphatic endothelium and demonstrated that histamine applied to spontaneously contracting collecting lymphatics inhibits contractions. Previous studies disagreed on whether histamine stimulates or inhibits lymphatic contractions, but also used differing concentrations, species, and preparations. Together these new reports shed light on how histamine acts within the lymphatic vasculature, but also raise important questions about the cell type on which histamine exerts its effects and the signaling pathways involved. This editorial briefly discusses the contribution of each study and its relevance to lymphatic biology. © 2014 John Wiley & Sons Ltd.

  18. Adipose Mesenchymal Stem Cell Secretome Modulated in Hypoxia for Remodeling of Radiation-Induced Salivary Gland Damage

    PubMed Central

    An, Hye-Young; Shin, Hyun-Soo; Choi, Jeong-Seok; Kim, Hun Jung

    2015-01-01

    Background and Purpose This study was conducted to determine whether a secretome from mesenchymal stem cells (MSC) modulated by hypoxic conditions to contain therapeutic factors contributes to salivary gland (SG) tissue remodeling and has the potential to improve irradiation (IR)-induced salivary hypofunction in a mouse model. Materials and Methods Human adipose mesenchymal stem cells (hAdMSC) were isolated, expanded, and exposed to hypoxic conditions (O2 < 5%). The hypoxia-conditioned medium was then filtered to a high molecular weight fraction and prepared as a hAdMSC secretome. The hAdMSC secretome was subsequently infused into the tail vein of C3H mice immediately after local IR once a day for seven consecutive days. The control group received equal volume (500 μL) of vehicle (PBS) only. SG function and structural tissue remodeling by the hAdMSC secretome were investigated. Human parotid epithelial cells (HPEC) were obtained, expanded in vitro, and then irradiated and treated with either the hypoxia-conditioned medium or a normoxic control medium. Cell proliferation and IR-induced cell death were examined to determine the mechanism by which the hAdMSC secretome exerted its effects. Results The conditioned hAdMSC secretome contained high levels of GM-CSF, VEGF, IL-6, and IGF-1. Repeated systemic infusion with the hAdMSC secretome resulted in improved salivation capacity and increased levels of salivary proteins, including amylase and EGF, relative to the PBS group. The microscopic structural integrity of SG was maintained and salivary epithelial (AQP-5), endothelial (CD31), myoepithelial (α-SMA) and SG progenitor cells (c-Kit) were successfully protected from radiation damage and remodeled. The hAdMSC secretome strongly induced proliferation of HPEC and led to a significant decrease in cell death in vivo and in vitro. Moreover, the anti-apoptotic effects of the hAdMSC secretome were found to be promoted after hypoxia-preconditioning relative to normoxia

  19. Estrogen attenuates chronic volume overload induced structural and functional remodeling in male rat hearts.

    PubMed

    Gardner, Jason D; Murray, David B; Voloshenyuk, Tetyana G; Brower, Gregory L; Bradley, Jessica M; Janicki, Joseph S

    2010-02-01

    We have previously reported gender differences in ventricular remodeling and development of heart failure using the aortocaval fistula model of chronic volume overload in rats. In contrast to males, female rats exhibited no adverse ventricular remodeling and less mortality in response to volume overload. This gender-specific cardioprotection was lost following ovariectomy and was partially restored using estrogen replacement. However, it is not known if estrogen treatment would be as effective in males. The purpose of this study was to evaluate the structural and functional effects of estrogen in male rats subjected to chronic volume overload. Four groups of male rats were studied at 3 days and 8 wk postsurgery as follows: fistula and sham-operated controls, with and without estrogen treatment. Biochemical and histological studies were performed at 3 days postsurgery, with chronic structural and functional effects studied at 8 wk. Measurement of systolic and diastolic pressure-volume relationships was obtained using a blood-perfused isolated heart preparation. Both fistula groups developed significant ventricular hypertrophy after 8 wk of volume overload. Untreated rats with fistula exhibited extensive ventricular dilatation, which was coupled with a loss of systolic function. Estrogen attenuated left ventricular dilatation and maintained function in treated rats. Estrogen treatment was also associated with a reduction in oxidative stress and circulating endothelin-1 levels, as well as prevention of matrix metalloproteinase-2 and -9 activation and breakdown of ventricular collagen in the early stage of remodeling. These data demonstrate that estrogen attenuates ventricular remodeling and disease progression in male rats subjected to chronic volume overload.

  20. Cigarette smoke selectively enhances viral PAMP- and virus-induced pulmonary innate immune and remodeling responses in mice.

    PubMed

    Kang, Min-Jong; Lee, Chun Geun; Lee, Jae-Young; Dela Cruz, Charles S; Chen, Zhijian J; Enelow, Richard; Elias, Jack A

    2008-08-01

    Viral infections have more severe consequences in patients who have been exposed to cigarette smoke (CS) than in those not exposed to CS. For example, in chronic obstructive pulmonary disease (COPD), viruses cause more severe disease exacerbation, heightened inflammation, and accelerated loss of lung function compared with other causes of disease exacerbation. Symptomatology and mortality in influenza-infected smokers is also enhanced. To test the hypothesis that these outcomes are caused by CS-induced alterations in innate immunity, we defined the effects of CS on pathogen-associated molecular pattern-induced (PAMP-induced) pulmonary inflammation and remodeling in mice. CS was found to enhance parenchymal and airway inflammation and apoptosis induced by the viral PAMP poly(I:C). CS and poly(I:C) also induced accelerated emphysema and airway fibrosis. The effects of a combination of CS and poly(I:C) were associated with early induction of type I IFN and IL-18, later induction of IL-12/IL-23 p40 and IFN-gamma, and the activation of double-stranded RNA-dependent protein kinase (PKR) and eukaryotic initiation factor-2alpha (eIF2alpha). Further analysis using mice lacking specific proteins indicated a role for TLR3-dependent and -independent pathways as well as a pathway or pathways that are dependent on mitochondrial antiviral signaling protein (MAVS), IL-18Ralpha, IFN-gamma, and PKR. Importantly, CS enhanced the effects of influenza but not other agonists of innate immunity in a similar fashion. These studies demonstrate that CS selectively augments the airway and alveolar inflammatory and remodeling responses induced in the murine lung by viral PAMPs and viruses.

  1. Remodeling of left circumflex coronary arterial tree in pacing-induced heart failure

    PubMed Central

    Huo, Yunlong

    2015-01-01

    Congestive heart failure (CHF) is a very serious heart disease that manifests an imbalance between left ventricle supply and demand. Although the mechanical demand of the failing heart has been well characterized, the systematic remodeling of the entire coronary arterial tree that constitutes the supply of the myocardium is lacking. We hypothesize that the well-known increase in ventricle wall stress during CHF causes coronary vascular rarefaction to increase the vascular flow resistance, which in turn compromises the perfusion of the heart. Morphometric (diameters, length, and numbers) data of the swine left circumflex (LCx) arterial tree were measured in both CHF (n = 6) and control (n = 6) groups, from which a computer reconstruction of the entire LCx tree was implemented down to the capillary level to enable a hemodynamic analysis of coronary circulation. The vascular flow resistance was increased by ∼75% due to a significant decrease of vessel numbers (∼45%) and diameters in the first capillary segments (∼10%) of the LCx arterial tree after 3-4 wk of pacing. The structural remodeling significantly changed the wall shear stress in vessel segments of the entire LCx arterial tree of CHF animals. This study enhances our knowledge of coronary arterial tree remodeling in heart failure, which provides a deeper understanding of the deterioration of supply-demand relation in left ventricle. PMID:26159756

  2. Cellular FLICE-inhibitory protein protects against cardiac remodeling induced by angiotensin II in mice.

    PubMed

    Li, Hongliang; Tang, Qi-Zhu; Liu, Chen; Moon, Mark; Chen, Manyin; Yan, Ling; Bian, Zhou-Yan; Zhang, Yan; Wang, Ai-Bing; Nghiem, Mai P; Liu, Peter P

    2010-12-01

    The development of cardiac hypertrophy in response to increased hemodynamic load and neurohormonal stress is initially a compensatory response that may eventually lead to ventricular dilatation and heart failure. Cellular FLICE-inhibitory protein (cFLIP) is a homologue of caspase 8 without caspase activity that inhibits apoptosis initiated by death receptor signaling. Previous studies showed that cFLIP expression was markedly decreased in the ventricular myocardium of patients with end-stage heart failure. However, the critical role of cFLIP on cardiac remodeling remains unclear. To specifically determine the role of cFLIP in pathological cardiac remodeling, we used heterozygote cFLIP(+/-) mice and transgenic mice with cardiac-specific overexpression of the human cFLIP(L) gene. Our results demonstrated that the cFLIP(+/-) mice were susceptible to cardiac hypertrophy and fibrosis through inhibition of mitogen-activated protein kinase kinase-extracellular signal-regulated kinase 1/2 signaling, whereas the transgenic mice displayed the opposite phenotype in response to angiotensin II stimulation. These studies indicate that cFLIP protein is a crucial component of the signaling pathway involved in cardiac remodeling and heart failure.

  3. Temperature induced remodeling of the photosynthetic machinery tunes photosynthesis in a thermophyllic alga.

    PubMed

    Nikolova, Denitsa; Weber, Dieter; Scholz, Martin; Bald, Till; Scharsack, Jörn Peter; Hippler, Michael

    2017-03-07

    The thermophilic alga C. merolae thrives in extreme environments (low pH and temperature between 40 and 56{degree sign}C. In this study we investigated the acclimation process of the alga to a colder temperature (25{degree sign}C). A long-term cell growth experiment revealed an extensive remodeling of the photosynthetic apparatus in the first 250 h of acclimation, which was followed by cell growth to an even higher density than the control (grown at 42{degree sign}C) cell density. Once the cells were shifted to the lower temperature, the proteins of the light-harvesting antenna were greatly down regulated and the phycobilisome (PBS) composition was altered. The amount of photosystem I and II (PSI and PSII) subunits was also decreased, but the chlorophyll to photosystems ratio remained unchanged. The 25{degree sign}C cells possessed a less efficient photon to oxygen conversion rate and require a 2.5 times higher light intensity to reach maximum photosynthetic efficiency. With respect to chlorophyll however the photosynthetic oxygen evolution rate of the 25{degree sign}C culture was 2 times higher than the control. Quantitative proteomics revealed that acclimation requires, beside remodeling of the photosynthetic apparatus, also adjustment of the machinery for protein folding, degradation and homeostasis In summary, these remodeling processes tuned photosynthesis according to the demands placed on the system and revealed the capability of C.merolae to grow under a broad range of temperatures.

  4. Numerical simulation of load-induced bone structural remodelling using stress-limit criterion.

    PubMed

    Marzban, Ali; Nayeb-Hashemi, Hamid; Vaziri, Ashkan

    2015-01-01

    A simple and efficient numerical method for predicting the remodelling of adaptive materials and structures under applied loading was presented and implemented within a finite element framework. The model uses the trajectorial architecture theory of optimisation to predict the remodelling of material microstructure and structural organisation under mechanical loading. We used the proposed model to calculate the density distribution of proximal femur in the frontal plane. The loading considered was the hip joint contact forces and muscular forces at the attachment sites of the muscles to the bone. These forces were estimated from a separate finite element calculation using a heterogeneous three-dimensional model of the proximal femur. The density distributions obtained by this procedure has a qualitative similarity with in vivo observations. Solutions displayed the characteristic high-density channels that are evident in the Dual X-ray Absorptiometry scan. There is also evidence of the intramedullary canal, as well as low-density regions in the femoral neck. Several parametric studies were carried out to highlight the advantages of the proposed method, which includes fast convergence and low-computational cost. The potential applications of the proposed method in predicting bone structural remodelling in cancer are also briefly discussed.

  5. Multiphoton microscopy of engineered dermal substitutes: assessment of 3D collagen matrix remodeling induced by fibroblasts contraction

    NASA Astrophysics Data System (ADS)

    Pena, A.-M.; Olive, C.; Michelet, J.-F.; Galey, J.-B.; Fagot, D.; Leroy, F.; Martin, J.-L.; Colonna, A.; Schanne-Klein, M.-C.

    2010-02-01

    One of the main functions of dermal fibroblasts is the generation of mechanical forces within their surrounding extracellular matrix. Investigating molecules that could modulate fibroblast contraction and act as potent anti aging ingredients requires the development of three-dimensional in situ imaging methodologies for dermal substitute analysis. Here we use multiphoton microscopy in order to investigate the fibroblast-induced collagen matrix reorganization in engineered dermal tissue and to evaluate the effect of Y27632, a RhoA kinase inhibitor on dermal substitutes contraction. We observe that collagen fibrils rearrange around fibroblast with increasing density in control samples, whereas collagen fibrils show no remodeling in the samples containing the RhoA kinase inhibitor. Moreover, when the culture medium containing the inhibitor was replaced with a control medium, the dermal substitutes presented the same 3D reorganization as the control samples, which indicates that the inhibitory effects are reversible. In conclusion, our study demonstrates the relevance of multiphoton microscopy to visualize three-dimensional remodeling of the matrix induced by fibroblast contraction.

  6. Multiphoton microscopy of engineered dermal substitutes: assessment of 3-D collagen matrix remodeling induced by fibroblast contraction

    NASA Astrophysics Data System (ADS)

    Pena, Ana-Maria; Fagot, Dominique; Olive, Christian; Michelet, Jean-François; Galey, Jean-Baptiste; Leroy, Frédéric; Beaurepaire, Emmanuel; Martin, Jean-Louis; Colonna, Anne; Schanne-Klein, Marie-Claire

    2010-09-01

    Dermal fibroblasts are responsible for the generation of mechanical forces within their surrounding extracellular matrix and can be potentially targeted by anti-aging ingredients. Investigation of the modulation of fibroblast contraction by these ingredients requires the implementation of three-dimensional in situ imaging methodologies. We use multiphoton microscopy to visualize unstained engineered dermal tissue by combining second-harmonic generation that reveals specifically fibrillar collagen and two-photon excited fluorescence from endogenous cellular chromophores. We study the fibroblast-induced reorganization of the collagen matrix and quantitatively evaluate the effect of Y-27632, a RhoA-kinase inhibitor, on dermal substitute contraction. We observe that collagen fibrils rearrange around fibroblasts with increasing density in control samples, whereas collagen fibrils show no remodeling in the samples containing the RhoA-kinase inhibitor. Moreover, we show that the inhibitory effects are reversible. Our study demonstrates the relevance of multiphoton microscopy to visualize three-dimensional remodeling of the extracellular matrix induced by fibroblast contraction or other processes.

  7. Anti-VEGF therapy induces ECM remodeling and mechanical barriers to therapy in colorectal cancer liver metastases.

    PubMed

    Rahbari, Nuh N; Kedrin, Dmitriy; Incio, Joao; Liu, Hao; Ho, William W; Nia, Hadi T; Edrich, Christina M; Jung, Keehoon; Daubriac, Julien; Chen, Ivy; Heishi, Takahiro; Martin, John D; Huang, Yuhui; Maimon, Nir; Reissfelder, Christoph; Weitz, Jurgen; Boucher, Yves; Clark, Jeffrey W; Grodzinsky, Alan J; Duda, Dan G; Jain, Rakesh K; Fukumura, Dai

    2016-10-12

    The survival benefit of anti-vascular endothelial growth factor (VEGF) therapy in metastatic colorectal cancer (mCRC) patients is limited to a few months because of acquired resistance. We show that anti-VEGF therapy induced remodeling of the extracellular matrix with subsequent alteration of the physical properties of colorectal liver metastases. Preoperative treatment with bevacizumab in patients with colorectal liver metastases increased hyaluronic acid (HA) deposition within the tumors. Moreover, in two syngeneic mouse models of CRC metastasis in the liver, we show that anti-VEGF therapy markedly increased the expression of HA and sulfated glycosaminoglycans (sGAGs), without significantly changing collagen deposition. The density of these matrix components correlated with increased tumor stiffness after anti-VEGF therapy. Treatment-induced tumor hypoxia appeared to be the driving force for the remodeling of the extracellular matrix. In preclinical models, we show that enzymatic depletion of HA partially rescued the compromised perfusion in liver mCRCs after anti-VEGF therapy and prolonged survival in combination with anti-VEGF therapy and chemotherapy. These findings suggest that extracellular matrix components such as HA could be a potential therapeutic target for reducing physical barriers to systemic treatments in patients with mCRC who receive anti-VEGF therapy.

  8. Functional blockade of α5β1 integrin induces scattering and genomic landscape remodeling of hepatic progenitor cells

    PubMed Central

    2010-01-01

    Background Cell scattering is a physiological process executed by stem and progenitor cells during embryonic liver development and postnatal organ regeneration. Here, we investigated the genomic events occurring during this process induced by functional blockade of α5β1 integrin in liver progenitor cells. Results Cells treated with a specific antibody against α5β1 integrin exhibited cell spreading and scattering, over-expression of liver stem/progenitor cell markers and activation of the ERK1/2 and p38 MAPKs signaling cascades, in a similar manner to the process triggered by HGF/SF1 stimulation. Gene expression profiling revealed marked transcriptional changes of genes involved in cell adhesion and migration, as well as genes encoding chromatin remodeling factors. These responses were accompanied by conspicuous spatial reorganization of centromeres, while integrin genes conserved their spatial positioning in the interphase nucleus. Conclusion Collectively, our results demonstrate that α5β1 integrin functional blockade induces cell migration of hepatic progenitor cells, and that this involves a dramatic remodeling of the nuclear landscape. PMID:20958983

  9. Bone Microenvironment Specific Roles of ITAM Adapter Signaling during Bone Remodeling Induced by Acute Estrogen-Deficiency

    PubMed Central

    Wu, Yalei; Torchia, James; Yao, Wei; Lane, Nancy E.; Lanier, Lewis L.; Nakamura, Mary C.; Humphrey, Mary Beth

    2007-01-01

    Immunoreceptor tyrosine-based activation motif (ITAM) signaling mediated by DAP12 or Fcε receptor Iγ chain (FcRγ) have been shown to be critical for osteoclast differentiation and maturation under normal physiological conditions. Their function in pathological conditions is unknown. We studied the role of ITAM signaling during rapid bone remodeling induced by acute estrogen-deficiency in wild-type (WT), DAP12-deficient (DAP12-/-), FcRγ-deficient (FcRγ-/-) and double-deficient (DAP12-/-FcRγ-/-) mice. Six weeks after ovariectomy (OVX), DAP12-/-FcRγ-/- mice showed resistance to lumbar vertebral body (LVB) trabecular bone loss, while WT, DAP12-/- and FcRγ-/- mice had significant LVB bone loss. In contrast, all ITAM adapter-deficient mice responded to OVX with bone loss in both femur and tibia of approximately 40%, relative to basal bone volumes. Only WT mice developed significant cortical bone loss after OVX. In vitro studies showed microenvironmental changes induced by OVX are indispensable for enhanced osteoclast formation and function. Cytokine changes, including TGFβ and TNFα, were able to induce osteoclastogenesis independent of RANKL in BMMs from WT but not DAP12-/- and DAP12-/-FcRγ-/- mice. FSH stimulated RANKL-induced osteoclast differentiation from BMMs in WT, but not DAP12-/- and DAP12-/-FcRγ-/- mice. Our study demonstrates that although ITAM adapter signaling is critical for normal bone remodeling, estrogen-deficiency induces an ITAM adapter-independent bypass mechanism allowing for enhanced osteoclastogenesis and activation in specific bony microenvironments. PMID:17611621

  10. Cisplatin-induced apoptosis involves a Fas-ROCK-ezrin-dependent actin remodelling in human colon cancer cells.

    PubMed

    Rebillard, Amélie; Jouan-Lanhouet, Sandrine; Jouan, Elodie; Legembre, Patrick; Pizon, Mathieu; Sergent, Odile; Gilot, David; Tekpli, Xavier; Lagadic-Gossmann, Dominique; Dimanche-Boitrel, Marie-Thérèse

    2010-05-01

    In human colon cancer cells, cisplatin-induced apoptosis involves the Fas death receptor pathway independent of Fas ligand. The present study explores the role of ezrin and actin cytoskeleton in relation with Fas receptor in this cell death pathway. In response to cisplatin treatment, a rapid and transient actin reorganisation is observed at the cell membrane by fluorescence microscopy after Phalloidin-FITC staining. This event is dependent on the membrane fluidification studied by electron paramagnetic resonance and necessary for apoptosis induction. Moreover, early after the onset of cisplatin treatment, ezrin co-localised with Fas at the cell membrane was visualised by membrane microscopy and was redistributed with Fas, FADD and procaspase-8 into membrane lipid rafts as shown on Western blots. In fact, cisplatin exposure results in an early small GTPase RhoA activation demonstrated by RhoA-GTP pull down, Rho kinase (ROCK)-dependent ezrin phosphorylation and actin microfilaments remodelling. Pretreatment with latrunculin A, an inhibitor of actin polymerisation, or specific extinction of ezrin or ROCK by RNA interference prevents both cisplatin-induced actin reorganisation and apoptosis. Interestingly, specific extinction of Fas receptor by RNA interference abrogates cisplatin-induced ROCK-dependent ezrin phosphorylation, actin reorganisation and apoptosis suggesting that Fas is a key regulator of cisplatin-induced actin remodelling and is indispensable for apoptosis. Thus, these findings show for the first time that phosphorylation of ezrin by ROCK via Fas receptor is involved in the early steps of cisplatin-induced apoptosis. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  11. [The macrophage contribution for maintaining lymphatic vessel in cornea].

    PubMed

    Maruyama, Kazuichi

    2014-11-01

    The presence of antigen-presenting cells and hem- and lymphangiogenesis in the cornea are risk factors for the rejection of corneal transplants. We previously reported that antigen-presenting cells such as macrophages (MPs) play an important role in the induction of lymphatic endothelial cells during inflammation. This prompted us to inquire whether the existence of lymphatic vessels in the cornea is associated with the activation of MPs during inflammation. To investigate this question, we performed suture placement on the cornea to induce inflammation. We found that a large number of MPs were recruited and that lymphatic vessels were formed in response. Next, as C57BL/6 mice have a higher rejection rate after corneal transplantation than BALB/c mice, we compared the corneas of C57BL/6 and BALB/c mice under normal and inflamed conditions. We found that the number of spontaneously formed lymphatic vessels in the C57BL/6 corneas was significantly greater than in the BALB/c corneas, and that there were more activated MPs in the C57BL/6 corneas than in the BALB/c corneas. Additionally, to confirm that activated MPs induced and maintained lymphatic vessels in the cornea, we depleted the number of MPs in C57BL/6 mice via clodronate liposomes. We found that MP depletion reduced the spontaneous formation of lymphatic vessels and reduced inflammation-induced lymphangiogenesis relative to control mice. Finally, we found that mice deficient in MP markers had fewer spontaneously formed lymphatic vessels and less lymphangiogenesis than control C57BL/6 mice. The evidence gathered in this study leads us to conclude that activated MPs appear to play an important role in the formation of new lymphatic vessels and in their maintenance.

  12. Blockade of FLT4 suppresses metastasis of melanoma cells by impaired lymphatic vessels.

    PubMed

    Lee, Ji Yoon; Hong, Seok-Ho; Shin, Minsang; Heo, Hye-Ryeon; Jang, In Ho

    2016-09-16

    The metastatic spread of tumor cells via lymphatic vessels affects the relapse of tumor patients. New lymphatic vessel formation, including lymphangiogenesis, is promoted in the tumor environment. The lymphangiogenic factor VEGF-C can mediate lymphatic vessel formation and induce tumor metastasis by binding with FLT4. In melanoma, metastasis via lymphatics such as lymph nodes is one of the main predictors of poor outcome. Thus, we investigated whether blockade of FLT4 can reduce metastasis via the suppression of lymphatic capillaries. Proliferative lymphatic capillaries in melanoma were estimated by immunohistochemistry using FLT4 antibody after the injection of the FLT4 antagonist MAZ51. The numbers of tumor modules in metastasised lungs were calculated by gross examination and lymphatic related factors were examined by qRT-PCR. MAZ51 injection resulted in the suppression of tumor size and module number and the inhibition of proliferative lymphatic vessels in the intratumoral region in the lung and proliferating melanoma cells in the lung compared to those of untreated groups. Additionally, high FLT4 and TNF-alpha were detected in melanoma-induced tissue, while lymphatic markers such as VEGF-C, FLT4 and Prox-1 were significantly decreased in MAZ51 treated groups, implying that anti-lymphangiogenesis by MAZ51 may provide a potential strategy to prevent tumor metastasis in melanoma and high number of lymphatic capillaries could be used diagnosis for severe metastasis. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Vagus nerve stimulation mitigates intrinsic cardiac neuronal remodeling and cardiac hypertrophy induced by chronic pressure overload in guinea pig

    PubMed Central

    Beaumont, Eric; Wright, Gary L.; Southerland, Elizabeth M.; Li, Ying; Chui, Ray; KenKnight, Bruce H.; Armour, J. Andrew

    2016-01-01

    Our objective was to determine whether chronic vagus nerve stimulation (VNS) mitigates pressure overload (PO)-induced remodeling of the cardioneural interface. Guinea pigs (n = 48) were randomized to right or left cervical vagus (RCV or LCV) implant. After 2 wk, chronic left ventricular PO was induced by partial (15–20%) aortic constriction. Of the 31 animals surviving PO induction, 10 were randomized to RCV VNS, 9 to LCV VNS, and 12 to sham VNS. VNS was delivered at 20 Hz and 1.14 ± 0.03 mA at a 22% duty cycle. VNS commenced 10 days after PO induction and was maintained for 40 days. Time-matched controls (n = 9) were evaluated concurrently. Echocardiograms were obtained before and 50 days after PO. At termination, intracellular current-clamp recordings of intrinsic cardiac (IC) neurons were studied in vitro to determine effects of therapy on soma characteristics. Ventricular cardiomyocyte sizes were assessed with histology along with immunoblot analysis of selected proteins in myocardial tissue extracts. In sham-treated animals, PO increased cardiac output (34%, P < 0.004), as well as systolic (114%, P < 0.04) and diastolic (49%, P < 0.002) left ventricular volumes, a hemodynamic response prevented by VNS. PO-induced enhancements of IC synaptic efficacy and muscarinic sensitivity of IC neurons were mitigated by chronic VNS. Increased myocyte size, which doubled in PO (P < 0.05), was mitigated by RCV. PO hypertrophic myocardium displayed decreased glycogen synthase (GS) protein levels and accumulation of the phosphorylated (inactive) form of GS. These PO-induced changes in GS were moderated by left VNS. Chronic VNS targets IC neurons accompanying PO to obtund associated adverse cardiomyocyte remodeling. PMID:26993230

  14. Vagus nerve stimulation mitigates intrinsic cardiac neuronal remodeling and cardiac hypertrophy induced by chronic pressure overload in guinea pig.

    PubMed

    Beaumont, Eric; Wright, Gary L; Southerland, Elizabeth M; Li, Ying; Chui, Ray; KenKnight, Bruce H; Armour, J Andrew; Ardell, Jeffrey L

    2016-05-15

    Our objective was to determine whether chronic vagus nerve stimulation (VNS) mitigates pressure overload (PO)-induced remodeling of the cardioneural interface. Guinea pigs (n = 48) were randomized to right or left cervical vagus (RCV or LCV) implant. After 2 wk, chronic left ventricular PO was induced by partial (15-20%) aortic constriction. Of the 31 animals surviving PO induction, 10 were randomized to RCV VNS, 9 to LCV VNS, and 12 to sham VNS. VNS was delivered at 20 Hz and 1.14 ± 0.03 mA at a 22% duty cycle. VNS commenced 10 days after PO induction and was maintained for 40 days. Time-matched controls (n = 9) were evaluated concurrently. Echocardiograms were obtained before and 50 days after PO. At termination, intracellular current-clamp recordings of intrinsic cardiac (IC) neurons were studied in vitro to determine effects of therapy on soma characteristics. Ventricular cardiomyocyte sizes were assessed with histology along with immunoblot analysis of selected proteins in myocardial tissue extracts. In sham-treated animals, PO increased cardiac output (34%, P < 0.004), as well as systolic (114%, P < 0.04) and diastolic (49%, P < 0.002) left ventricular volumes, a hemodynamic response prevented by VNS. PO-induced enhancements of IC synaptic efficacy and muscarinic sensitivity of IC neurons were mitigated by chronic VNS. Increased myocyte size, which doubled in PO (P < 0.05), was mitigated by RCV. PO hypertrophic myocardium displayed decreased glycogen synthase (GS) protein levels and accumulation of the phosphorylated (inactive) form of GS. These PO-induced changes in GS were moderated by left VNS. Chronic VNS targets IC neurons accompanying PO to obtund associated adverse cardiomyocyte remodeling.

  15. NFATc3 Mediates Chronic Hypoxia-induced Pulmonary Arterial Remodeling with α-Actin Up-regulation

    PubMed Central

    de Frutos, S.; Spangler, R.; Alò, D.; González Bosc, L. V.

    2009-01-01

    Physiological responses to chronic hypoxia include polycythemia, pulmonary arterial remodeling and vasoconstriction. Chronic hypoxia causes pulmonary arterial hypertension leading to right ventricular hypertrophy and heart failure. During pulmonary hypertension, pulmonary arteries exhibit increased expression of smooth muscle-α-actin and -myosin heavy chain. NFATc3 (nuclear factor of activated T cells isoform c3), which is a Ca2+-dependent transcription factor, has been recently linked to smooth muscle phenotypic maintenance through the regulation of the expression of α-actin. The aim of this study was to determine if: a) NFATc3 is expressed in murine pulmonary arteries, b) hypoxia induces NFAT activation, c) NFATc3 mediates the up-regulation of α-actin during chronic hypoxia, and d) NFATc3 is involved in chronic hypoxia-induced pulmonary vascular remodeling. NFATc3 transcript and protein were found in pulmonary arteries. NFAT-luciferase reporter mice were exposed to normoxia (630 torr) or hypoxia (380 torr) for 2, 7 or 21 days. Exposure to hypoxia elicited a significant increase in luciferase activity and pulmonary arterial smooth muscle nuclear NFATc3 localization, demonstrating NFAT activation. Hypoxia induced up-regulation of α-actin and was prevented by the calcineurin/NFAT inhibitor, cyclosporin A (25 mg/Kg/day s.c.). In addition, NFATc3 knockout mice did not showed increased α-actin levels and arterial wall thickness after hypoxia. These results strongly suggest that NFATc3 plays a role in the chronic hypoxia-induced vascular changes that underlie pulmonary hypertension. PMID:17403661

  16. Lymphatic System in Cardiovascular Medicine.

    PubMed

    Aspelund, Aleksanteri; Robciuc, Marius R; Karaman, Sinem; Makinen, Taija; Alitalo, Kari

    2016-02-05

    The mammalian circulatory system comprises both the cardiovascular system and the lymphatic system. In contrast to the blood vascular circulation, the lymphatic system forms a unidirectional transit pathway from the extracellular space to the venous system. It actively regulates tissue fluid homeostasis, absorption of gastrointestinal lipids, and trafficking of antigen-presenting cells and lymphocytes to lymphoid organs and on to the systemic circulation. The cardinal manifestation of lymphatic malfunction is lymphedema. Recent research has implicated the lymphatic system in the pathogenesis of cardiovascular diseases including obesity and metabolic disease, dyslipidemia, inflammation, atherosclerosis, hypertension, and myocardial infarction. Here, we review the most recent advances in the field of lymphatic vascular biology, with a focus on cardiovascular disease. © 2016 American Heart Association, Inc.

  17. Lymphatic vessel density and function in experimental bladder cancer

    PubMed Central

    Saban, Marcia R; Towner, Rheal; Smith, Nataliya; Abbott, Andrew; Neeman, Michal; Davis, Carole A; Simpson, Cindy; Maier, Julie; Mémet, Sylvie; Wu, Xue-Ru; Saban, Ricardo

    2007-01-01

    Background The lymphatics form a second circulatory system that drains the extracellular fluid and proteins from the tumor microenvironment, and provides an exclusive environment in which immune cells interact and respond to foreign antigen. Both cancer and inflammation are known to induce lymphangiogenesis. However, little is known about bladder lymphatic vessels and their involvement in cancer formation and progression. Methods A double transgenic mouse model was generated by crossing a bladder cancer-induced transgenic, in which SV40 large T antigen was under the control of uroplakin II promoter, with another transgenic mouse harboring a lacZ reporter gene under the control of an NF-κB-responsive promoter (κB-lacZ) exhibiting constitutive activity of β-galactosidase in lymphatic endothelial cells. In this new mouse model (SV40-lacZ), we examined the lymphatic vessel density (LVD) and function (LVF) during bladder cancer progression. LVD was performed in bladder whole mounts and cross-sections by fluorescent immunohistochemistry (IHC) using LYVE-1 antibody. LVF was assessed by real-time in vivo imaging techniques using a contrast agent (biotin-BSA-Gd-DTPA-Cy5.5; Gd-Cy5.5) suitable for both magnetic resonance imaging (MRI) and near infrared fluorescence (NIRF). In addition, IHC of Cy5.5 was used for time-course analysis of co-localization of Gd-Cy5.5 with LYVE-1-positive lymphatics and CD31-positive blood vessels. Results SV40-lacZ mice develop bladder cancer and permitted visualization of lymphatics. A significant increase in LVD was found concomitantly with bladder cancer progression. Double labeling of the bladder cross-sections with LYVE-1 and Ki-67 antibodies indicated cancer-induced lymphangiogenesis. MRI detected mouse bladder cancer, as early as 4 months, and permitted to follow tumor sizes during cancer progression. Using Gd-Cy5.5 as a contrast agent for MRI-guided lymphangiography, we determined a possible reduction of lymphatic flow within the

  18. Identification of transcription factors and gene clusters in rabbit smooth muscle cells during high flow-induced vascular remodeling via microarray.

    PubMed

    Zhang, Zhaolong; Yang, Pengfei; Yao, Pengfei; Dai, Dongwei; Yu, Ying; Zhou, Yu; Huang, Qinghai; Liu, Jianmin

    2016-01-10

    Sustained blood flow, especially high blood flow causes the remodeling of arteries. The molecular mechanism of vascular remodeling has been mainly investigated in cultured cells. However, the in vivo molecular mechanism is poorly understood. In this study, we performed microarray analysis to explore the gene expression profile of smooth muscle cells (SMCs) during vascular remodeling. Transcriptional profiles indicated that 947 genes were differentially expressed in SMCs responding to high flow compared with the sham control, of which 617 genes were up-regulated and 330 genes were down-regulated. Gene ontology analysis revealed the special participation of extracellular matrix related genes during high flow-induced vascular remodeling. KEGG pathway analysis showed the enrichment of metabolism and immune function associated genes in SMCs exposed to high flow. Besides, we also identified 25 differentially expressed transcription factors potentially impacted by hemodynamic insult. Finally, we revealed FOXN4 as a novel transcription factor that could modulate MMP2 and MMP9 transcriptional activity. Collectively, our results revealed major gene clusters and transcription factors in SMCs during vascular remodeling which may provide an insight into the molecular mechanism of vascular remodeling and facilitate the screening of candidate genes for vascular diseases.

  19. Wine lees modulate lipid metabolism and induce fatty acid remodelling in zebrafish.

    PubMed

    Caro, M; Sansone, A; Amezaga, J; Navarro, V; Ferreri, C; Tueros, I

    2017-03-21

    This study investigates the ability of a polyphenolic extract obtained from a wine lees by-product to modulate zebrafish lipid metabolism. Lees from a Spanish winery were collected and the polyphenolic extract was chemically characterised in terms of antioxidant capacity, total phenolic content and the individual main phenolic compounds. The effects of the extract on lipid metabolism were evaluated using a zebrafish animal model. Lees are rich in polyphenols (42.33 mg gallic acid equivalent per g dry matter) with high antioxidant capacity (56.04 mg Trolox equivalent per g dry matter), rutin and quercetin being their main identified polyphenols. The biological effects of lees extract included (i) a reduction in zebrafish embryos' fat reserve (40%), (ii) changes in the expression of lipid metabolism key genes, (iii) remodelling of the fatty acid content in phospholipid and triglyceride fractions of zebrafish embryos and (iv) reduction in the trans fatty acid content. On the whole, wine lees polyphenolic extract was effective at modulating zebrafish lipid metabolism evidencing remodelling effects and antioxidant properties that can be further developed for food innovation.

  20. Cyclooxygenase-2-derived prostanoids reduce inward arterial remodeling induced by blood flow reduction in old obese Zucker rat mesenteric arteries.

    PubMed

    Vessières, Emilie; Belin de Chantemèle, Eric J; Guihot, Anne-Laure; Jardel, Alain; Toutain, Bertrand; Loufrani, Laurent; Henrion, Daniel

    2013-01-01

    Obesity is associated with altered arterial structure and function leading to arterial narrowing in most vascular beds, especially when associated with aging. Nevertheless, mesenteric blood flow remains elevated in obese rats, although the effect of aging remains unknown. We investigated mesenteric artery narrowing following blood flow reduction in vivo in 3- and 12-month-old obese Zucker rats. After 21 days, inward remodeling occurred in low flow (LF) arteries in young and old lean rats and in young obese rats (30% diameter reduction). Diameter did not significantly decrease in old obese rats. Phenylephrine-mediated contraction was reduced by approximately 20% in LF arteries in all groups but in old obese rat arteries in which the decrease reached 80%. LF arteries expressed cyclooxygenase-2 and blood 6-keto-PGF1alpha (prostacyclin metabolite) was elevated in old obese rats. In old obese rats, acute cyclooxygenase-2 blockade restored phenylephrine-mediated contraction in LF arteries and chronic cyclooxygenase-2 blockade restored inward remodeling and contractility to control level. Thus, in old obese rats, cyclooxygenase-2-derived prostacyclin prevented the diameter reduction induced by a chronic decrease in blood flow. This adaptation is in favor of a preserved perfusion of the mesentery by contrast with other vascular territories, possibly amplifying the vascular disorders occurring in obesity.

  1. An Arabidopsis ABC Transporter Mediates Phosphate Deficiency-Induced Remodeling of Root Architecture by Modulating Iron Homeostasis in Roots.

    PubMed

    Dong, Jinsong; Piñeros, Miguel A; Li, Xiaoxuan; Yang, Haibing; Liu, Yu; Murphy, Angus S; Kochian, Leon V; Liu, Dong

    2017-02-13

    The remodeling of root architecture is a major developmental response of plants to phosphate (Pi) deficiency and is thought to enhance a plant's ability to forage for the available Pi in topsoil. The underlying mechanism controlling this response, however, is poorly understood. In this study, we identified an Arabidopsis mutant, hps10 (hypersensitive to Pi starvation 10), which is morphologically normal under Pi sufficient condition but shows increased inhibition of primary root growth and enhanced production of lateral roots under Pi deficiency. hps10 is a previously identified allele (als3-3) of the ALUMINUM SENSITIVE3 (ALS3) gene, which is involved in plant tolerance to aluminum toxicity. Our results show that ALS3 and its interacting protein AtSTAR1 form an ABC transporter complex in the tonoplast. This protein complex mediates a highly electrogenic transport in Xenopus oocytes. Under Pi deficiency, als3 accumulates higher levels of Fe(3+) in its roots than the wild type does. In Arabidopsis, LPR1 (LOW PHOSPHATE ROOT1) and LPR2 encode ferroxidases, which when mutated, reduce Fe(3+) accumulation in roots and cause root growth to be insensitive to Pi deficiency. Here, we provide compelling evidence showing that ALS3 cooperates with LPR1/2 to regulate Pi deficiency-induced remodeling of root architecture by modulating Fe homeostasis in roots.

  2. Hepatitis B virus X induces inflammation and cancer in mice liver through dysregulation of cytoskeletal remodeling and lipid metabolism

    PubMed Central

    Xu, Zhongwei; Zhai, Linghui; Yi, Tailong; Gao, Huiying; Fan, Fengxu; Li, Yanchang; Wang, Youliang; Li, Ning; Xing, Xiaohua; Su, Na; Wu, Feilin; Chang, Lei; Chen, Xiuli; Dai, Erhei; Zhao, Chao; Yang, Xiao; Cui, Chunping; Xu, Ping

    2016-01-01

    Hepatitis B virus X protein (HBx) participates in the occurrence and development processes of hepatocellular carcinoma (HCC) as a multifunctional regulation factor. However, the underlying molecular mechanism remains obscure. Here, we describe the use of p21HBx/+ mouse and SILAM (Stable Isotope Labeling in Mammals) strategy to define the pathological mechanisms for the occurrence and development of HBx induced liver cancer. We systematically compared a series of proteome samples from regular mice, 12- and 24-month old p21HBx/+ mice representing the inflammation and HCC stages of liver disease respectively and their nontransgenic wild-type (WT) littermates. Totally we identified 22 and 97 differentially expressed proteins out of a total of 2473 quantified proteins. Bioinformatics analysis suggested that the lipid metabolism and CDC42-induced cytoskeleton remodeling pathways were strongly activated by the HBx transgene. Interestingly, the protein-protein interaction MS study revealed that HBx directly interacted with multiple proteins in these two pathways. The same effect of up-regulation of cytoskeleton and lipid metabolism related proteins, including CDC42, CFL1, PPARγ and ADFP, was also observed in the Huh-7 cells transfected with HBx. More importantly, CFL1 and ADFP were specifically accumulated in HBV-associated HCC (HBV-HCC) patient samples, and their expression levels were positively correlated with the severity of HBV-related liver disease. These results provide evidence that HBx induces the dysregulation of cytoskeleton remodeling and lipid metabolism and leads to the occurrence and development of liver cancer. The CFL1 and ADFP might be served as potential biomarkers for prognosis and diagnosis of HBV-HCC. PMID:27708241

  3. Bone marrow transplantation transfers age-related susceptibility to neovascular remodeling in murine laser-induced choroidal neovascularization.

    PubMed

    Espinosa-Heidmann, Diego G; Malek, Goldis; Mettu, Priyatham S; Caicedo, Alejandro; Saloupis, Peter; Gach, Sarah; Dunnon, Askia K; Hu, Peng; Spiga, Maria-Grazia; Cousins, Scott W

    2013-11-13

    Neovascular remodeling (NVR), the progression of small capillaries into large-caliber arterioles with perivascular fibrosis, represents a major therapeutic challenge in neovascular age-related macular degeneration (AMD). Neovascular remodeling occurs after laser-induced choroidal neovascularization (CNV) in aged but not young mice. Additionally, bone marrow-derived cells, including macrophages, endothelial precursor cells, and mesenchymal precursor cells, contribute to CNV severity. In this study, we investigated the impact of aged bone marrow transplantation (BMT) on the degree of fibrosis, size, and vascular morphology of CNV lesions in a mouse model of laser-induced CNV. Young (2 months) and old (16 months) mice were transplanted with green fluorescent protein (GFP)-labeled bone marrow isolated from either young or old donors. Laser CNV was induced 1 month following transplant, and eyes were analyzed via choroidal flat mounts and immunohistochemistry 1 month postlaser. The identity of cells infiltrating CNV lesions was determined using specific markers for the labeled transplanted cells (GFP+), macrophages (F4/80+), perivascular mesenchymal-derived cells (smooth muscle actin, SMA+), and endothelial cells (CD31+). Bone marrow transplantation from aged mice transferred susceptibility to NVR into young recipients. Inversely, transplantation of young marrow into old mice prevented NVR, preserving small size and minimal fibrosis. Mice with NVR demonstrated a greater relative contribution of marrow-derived SMA+ perivascular mesenchymal cells as compared to other cells. Our findings indicate that the status of bone marrow is an important determining factor of neovascular severity. Furthermore, we find that perivascular mesenchymal cells, rather than endothelial cells, derived from aged bone marrow may contribute to increased CNV severity in this murine model of experimental neovascularization.

  4. Bone Marrow Transplantation Transfers Age-Related Susceptibility to Neovascular Remodeling in Murine Laser-Induced Choroidal Neovascularization

    PubMed Central

    Espinosa-Heidmann, Diego G.; Malek, Goldis; Mettu, Priyatham S.; Caicedo, Alejandro; Saloupis, Peter; Gach, Sarah; Dunnon, Askia K.; Hu, Peng; Spiga, Maria-Grazia; Cousins, Scott W.

    2013-01-01

    Purpose. Neovascular remodeling (NVR), the progression of small capillaries into large-caliber arterioles with perivascular fibrosis, represents a major therapeutic challenge in neovascular age-related macular degeneration (AMD). Neovascular remodeling occurs after laser-induced choroidal neovascularization (CNV) in aged but not young mice. Additionally, bone marrow–derived cells, including macrophages, endothelial precursor cells, and mesenchymal precursor cells, contribute to CNV severity. In this study, we investigated the impact of aged bone marrow transplantation (BMT) on the degree of fibrosis, size, and vascular morphology of CNV lesions in a mouse model of laser-induced CNV. Methods. Young (2 months) and old (16 months) mice were transplanted with green fluorescent protein (GFP)-labeled bone marrow isolated from either young or old donors. Laser CNV was induced 1 month following transplant, and eyes were analyzed via choroidal flat mounts and immunohistochemistry 1 month postlaser. The identity of cells infiltrating CNV lesions was determined using specific markers for the labeled transplanted cells (GFP+), macrophages (F4/80+), perivascular mesenchymal-derived cells (smooth muscle actin, SMA+), and endothelial cells (CD31+). Results. Bone marrow transplantation from aged mice transferred susceptibility to NVR into young recipients. Inversely, transplantation of young marrow into old mice prevented NVR, preserving small size and minimal fibrosis. Mice with NVR demonstrated a greater relative contribution of marrow-derived SMA+ perivascular mesenchymal cells as compared to other cells. Conclusions. Our findings indicate that the status of bone marrow is an important determining factor of neovascular severity. Furthermore, we find that perivascular mesenchymal cells, rather than endothelial cells, derived from aged bone marrow may contribute to increased CNV severity in this murine model of experimental neovascularization. PMID:24135751

  5. The SWI/SNF chromatin remodeling complex regulates myocardin-induced smooth muscle-specific gene expression

    PubMed Central

    Zhou, Jiliang; Zhang, Min; Fang, Hong; El-Mounayri, Omar; Rodenberg, Jennifer M.; Imbalzano, Anthony N.; Herring, B. Paul

    2009-01-01

    Objective Transcription regulatory complexes comprising myocardin and serum response factor (SRF) are critical for the transcriptional regulation of many smooth muscle-specific genes. However, little is known about the epigenetic mechanisms that regulate the activity of these complexes. In the current study, we investigated the role of SWI/SNF ATP-dependent chromatin remodeling enzymes in regulating the myogenic activity of myocardin. Methods and Results We found that both Brg1 and Brm are required for maintaining expression of several smooth muscle-specific genes in primary cultures of aortic smooth muscle cells. Furthermore, the ability of myocardin to induce expression of smooth muscle-specific genes is abrogated in cells expressing dominant negative Brg1. In SW13 cells, that lack endogenous Brg1 and Brm1, myocardin is unable to induce expression of smooth muscle-specific genes. Whereas, reconstitution of wild type, or bromodomain mutant forms Brg1 or Brm1, into SW13 cells restored their responsiveness to myocardin. SWI/SNF complexes were found to be required for myocardin to increase SRF binding to the promoters of smooth muscle-specific genes. Brg1 and Brm directly bind to the N-terminus of myocardin, in vitro, through their ATPase domains and Brg1 forms a complex with SRF and myocardin in vivo in smooth muscle cells. Conclusion These data demonstrate that the ability of myocardin to induce smooth muscle-specific gene expression is dependent on its interaction with SWI/SNF ATP-dependent chromatin remodeling complexes. PMID:19342595

  6. Visualisation and stereological assessment of blood and lymphatic vessels.

    PubMed

    Lokmic, Zerina; Mitchell, Geraldine M

    2011-06-01

    The physiological processes involved in tissue development and regeneration also include the parallel formation of blood and lymphatic vessel circulations which involves their growth, maturation and remodelling. Both vascular systems are also frequently involved in the development and progression of pathological conditions in tissues and organs. The blood vascular system circulates oxygenated blood and nutrients at appropriate physiological levels for tissue survival, and efficiently removes all waste products including carbon dioxide. This continuous network consists of the heart, aorta, arteries, arterioles, capillaries, post-capillary venules, venules, veins and vena cava. This system exists in an interstitial environment together with the lymphatic vascular system, including lymph nodes, which aids maintenance of body fluid balance and immune surveillance. To understand the process of vascular development, vascular network stability, remodelling and/or regression in any research model under any experimental conditions, it is necessary to clearly and unequivocally identify and quantify all elements of the vascular network. By utilising stereological methods in combination with cellular markers for different vascular cell components, it is possible to estimate parameters such as surface density and surface area of blood vessels, length density and length of blood vessels as well as absolute vascular volume. This review examines the current strategies used to visualise blood vessels and lymphatic vessels in two- and three-dimensions and the basic principles of vascular stereology used to quantify vascular network parameters.

  7. Radiation therapy causes loss of dermal lymphatic vessels and interferes with lymphatic function by TGF-β1-mediated tissue fibrosis

    PubMed Central

    Avraham, Tomer; Yan, Alan; Zampell, Jamie C.; Daluvoy, Sanjay V.; Haimovitz-Friedman, Adriana; Cordeiro, Andrew P.

    2010-01-01

    Although radiation therapy is a major risk factor for the development of lymphedema following lymphadenectomy, the mechanisms responsible for this effect remain unknown. The purpose of this study was therefore to determine the effects of radiation on lymphatic endothelial cells (LECs) and lymphatic function. The tails of wild-type or acid sphingomyelinase (ASM)-deficient mice were treated with 0, 15, or 30 Gy of radiation and then analyzed for LEC apoptosis and lymphatic function at various time points. To analyze the effects of radiation fibrosis on lymphatic function, we determined the effects of transforming growth factor (TGF)-β1 blockade after radiation in vivo. Finally, we determined the effects of radiation and exogenous TGF-β1 on LECs in vitro. Radiation caused mild edema that resolved after 12–24 wk. Interestingly, despite resolution of tail edema, irradiated animals displayed persistent lymphatic dysfunction. Radiation caused loss of capillary lymphatics and was associated with a dose-dependent increase in LEC apoptosis. ASM−/− mice had significantly less LEC apoptosis; however, this finding did not translate to improved lymphatic function at later time points. Short-term blockade of TGF-β1 function after radiation markedly decreased tissue fibrosis and significantly improved lymphatic function but did not alter LEC apoptosis. Radiation therapy decreases lymphatic reserve by causing depletion of lymphatic vessels and LECs as well as promoting soft tissue fibrosis. Short-term inhibition of TGF-β1 activity following radiation improves lymphatic function and is associated with decreased soft tissue fibrosis. ASM deficiency confers LEC protection from radiation-induced apoptosis but does not prevent lymphatic dysfunction. PMID:20519446

  8. The role of the reduction of spiral artery remodeling and heme oxygenase 1 in mediating AT1-AA-induced hypertension and intrauterine growth restriction in pregnant rats.

    PubMed

    Zhang, Dan; Wang, Leilei; Qiao, Chong; Yu, Yang; Fu, Lihua; Shang, Tao

    2014-11-01

    Recently, emerging evidence has indicated that preeclamptic women who have angiotensin receptor agonistic autoantibodies (AT1-AA), these antibodies contribute to features of the disease. The purpose of this study was to determine the role of spiral artery remodeling in mediating AT1-AA-induced hypertension and intrauterine growth restriction in pregnant rats. We hypothesized that AT1-AA-mediated heme oxygenase 1 (HO-1) reduction contributes to decreased spiral artery remodeling. Rat AT1-AA and an HO-1 inducer were administered to pregnant rats. Mean arterial pressure (MAP) increased from 98 ± 4 mm Hg in normal pregnant rats to 113 ± 6 mm Hg in AT1-AA-infused rats (p < 0.05), which was significantly attenuated by the HO-1 inducer (103 ± 2 mm Hg). Fetal weight was also attenuated by HO-1 inducer, and kidney and liver development was adversely affected. Spiral artery remodeling was significantly reduced in AT1-AA-treated pregnant rats compared with that in normal pregnant rats, and this was significantly ameliorated by an HO-1 inducer. Our findings demonstrate that AT1-AA-mediated HO-1 reduction contributes to reduced spiral artery remodeling, and is one mechanism whereby AT1-AA mediates hypertension and intrauterine growth retardation. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  9. Green tea induces annexin-I expression in human lung adenocarcinoma A549 cells: involvement of annexin-I in actin remodeling.

    PubMed

    Lu, Qing-Yi; Jin, Yu Sheng; Zhang, Zuo-Feng; Le, Anh D; Heber, David; Li, Frederick P; Dubinett, Steven M; Rao, Jian Yu

    2007-05-01

    Green tea polyphenols exhibit multiple antitumor activities in various in vitro and in vivo tumor models, and the mechanisms of action are not clear. Previously, we found that green tea extract (GTE) regulates actin remodeling in different cell culture systems. Actin remodeling plays an important role in cancer cell morphology, cell adhesion, motility, and invasion. Using proteomic approaches, we found GTE-induced expression of annexin-I, a multifunctional actin binding protein, in these cell lines. In this study, we aimed to further define the functional role of GTE-induced annexin-I expression in actin remodeling, cell adhesion, and motility in lung adenocarcinoma A549 cells. We found that GTE stimulates the expression of annexin-I in a dose-dependent fashion. The GTE-induced annexin-I expression appears to be at the transcription level, and the increased annexin-I expression mediates actin polymerization, resulting in enhanced cell adhesion and decreased motility. Annexin-I specific interference resulted in loss of GTE-induced actin polymerization and cell adhesion, but not motility. In fact, annexin-I specific interference itself inhibited motility even without GTE. Together, annexin-I plays an important role in GTE-induced actin remodeling, and it may serve as a potential molecular target associated with the anticancer activities of green tea.

  10. Mechanosensitive transient receptor potential vanilloid 4 regulates Dermatophagoides farinae-induced airway remodeling via 2 distinct pathways modulating matrix synthesis and degradation.

    PubMed

    Gombedza, Farai; Kondeti, Vinay; Al-Azzam, Nosayba; Koppes, Stephanie; Duah, Ernest; Patil, Prachi; Hexter, Madison; Phillips, Daniel; Thodeti, Charles K; Paruchuri, Sailaja

    2017-04-01

    Contributions of mechanical signals to airway remodeling during asthma are poorly understood. Transient receptor potential vanilloid 4 (TRPV4), a mechanosensitive ion channel, has been implicated in cardiac and pulmonary fibrosis; however, its role in asthma remains elusive. Employing a Dermatophagoides farinae-induced asthma model, we report here that TRPV4-knockout mice were protected from D. farinae-induced airway remodeling. Furthermore, lung fibroblasts that were isolated from TRPV4-knockout mice showed diminished differentiation potential compared with wild-type mice. Fibroblasts from asthmatic lung exhibited increased TRPV4 activity and enhanced differentiation potential compared with normal human lung fibroblasts. Of interest, TGF-β1 treatment enhanced TRPV4 activation in a PI3K-dependent manner in normal human lung fibroblasts in vitro Mechanistically, TRPV4 modulated matrix remodeling in the lung via 2 distinct but dependent pathways: one enhances matrix deposition by fibrotic gene activation, whereas the other slows down matrix degradation by increased plasminogen activator inhibitor 1. Of importance, both pathways are regulated by Rho/myocardin-related transcription factor-A and contribute to fibroblast differentiation and matrix remodeling in the lung. Thus, our results support a unique role for TRPV4 in D. farinae-induced airway remodeling and warrant further studies in humans for it to be used as a novel therapeutic target in the treatment of asthma.-Gombedza, F., Kondeti, V., Al-Azzam, N., Koppes, S., Duah, E., Patil, P., Hexter, M., Phillips, D., Thodeti, C. K., Paruchuri, S. Mechanosensitive transient receptor potential vanilloid 4 regulates Dermatophagoides farinae-induced airway remodeling via 2 distinct pathways modulating matrix synthesis and degradation. © FASEB.

  11. Bicuspid aortic valve hemodynamics induces abnormal medial remodeling in the convexity of porcine ascending aortas.

    PubMed

    Atkins, Samantha K; Cao, Kai; Rajamannan, Nalini M; Sucosky, Philippe

    2014-11-01

    The type-I bicuspid aortic valve (BAV), which differs from the normal tricuspid aortic valve (TAV) most commonly by left-right coronary cusp fusion, is frequently associated with secondary aortopathies. While BAV aortic dilation has been linked to a genetic predisposition, hemodynamics has emerged as a potential alternate etiology. However, the link between BAV hemodynamics and aortic medial degeneration has not been established. The objective of this study was to compare the regional wall shear stresses (WSS) in a TAV and BAV ascending aorta (AA) and to isolate ex vivo their respective impact on aortic wall remodeling. The WSS environments generated in the convex region of a TAV and BAV AA were predicted through fluid-structure interaction (FSI) simulations in an aorta model subjected to both valvular flows. Remodeling of porcine aortic tissue exposed to TAV and BAV AA WSS for 48 h in a cone-and-plate bioreactor was investigated via immunostaining, immunoblotting and zymography. FSI simulations revealed the existence of larger and more unidirectional WSS in the BAV than in the TAV AA convexity. Exposure of normal aortic tissue to BAV AA WSS resulted in increased MMP-2 and MMP-9 expressions and MMP-2 activity but similar fibrillin-1 content and microfibril organization relative to the TAV AA WSS treatment. This study confirms the sensitivity of aortic tissue to WSS abnormalities and demonstrates the susceptibility of BAV hemodynamic stresses to focally mediate aortic medial degradation. The results provide compelling support to the important role of hemodynamics in BAV secondary aortopathy.

  12. Novel role of immature myeloid cells in formation of new lymphatic vessels associated with inflammation and tumors.

    PubMed

    Ran, Sophia; Wilber, Andrew

    2017-04-13

    Inflammation triggers an immune cell-driven program committed to restoring homeostasis to injured tissue. Central to this process is vasculature restoration, which includes both blood and lymphatic networks. Generation of new vessels or remodeling of existing vessels are also important steps in metastasis-the major cause of death for cancer patients. Although roles of the lymphatic system in regulation of inflammation and cancer metastasis are firmly established, the mechanisms underlying the formation of new lymphatic vessels remain a subject of debate. Until recently, generation of new lymphatics in adults was thought to occur exclusively through sprouting of existing vessels without help from recruited progenitors. However, emerging findings from clinical and experimental studies show that lymphoendothelial progenitors, particularly those derived from immature myeloid cells, play an important role in this process. This review summarizes current evidence for the existence and significant roles of myeloid-derived lymphatic endothelial cell progenitors (M-LECPs) in generation of new lymphatics. We describe specific markers of M-LECPs and discuss their biologic behavior in culture and in vivo, as well as currently known molecular mechanisms of myeloid-lymphatic transition (MLT). We also discuss the implications of M-LECPs for promoting adaptive immunity, as well as cancer metastasis. We conclude that improved mechanistic understanding of M-LECP differentiation and its role in adult lymphangiogenesis may lead to new therapeutic approaches for correcting lymphatic insufficiency or excessive formation of lymphatic vessels in human disorders.

  13. Altered Liver Proteoglycan/Glycosaminoglycan Structure as a Manifestation of Extracellular Matrix Remodeling upon BCG-induced Granulomatosis in Mice.

    PubMed

    Kim, L B; Shkurupy, V A; Putyatina, A N

    2017-01-01

    Experimental BCG-induced granulomatosis in mice was used to study changes in the dynamics of individual liver proteoglycan components reflecting phasic extracellular matrix remodeling, determined by the host-parasite interaction and associated with granuloma development. In the early BCG-granulomatosis period, the increase in individual proteoglycan components promotes granuloma formation, providing conditions for mycobacteria adhesion to host cells, migration of phagocytic cells from circulation, and cell-cell interaction leading to granuloma development and fibrosis. Later, reduced reserve capacity of the extracellular matrix, development of interstitial fibrosis and granuloma fibrosis can lead to trophic shortage for cells within the granulomas, migration of macrophages out of them, and development of spontaneous necrosis and apoptosis typical of tuberculosis.

  14. The poly(ADP-ribose)-dependent chromatin remodeler Alc1 induces local chromatin relaxation upon DNA damage

    PubMed Central

    Sellou, Hafida; Lebeaupin, Théo; Chapuis, Catherine; Smith, Rebecca; Hegele, Anna; Singh, Hari R.; Kozlowski, Marek; Bultmann, Sebastian; Ladurner, Andreas G.; Timinszky, Gyula; Huet, Sébastien

    2016-01-01

    Chromatin relaxation is one of the earliest cellular responses to DNA damage. However, what determines these structural changes, including their ATP requirement, is not well understood. Using live-cell imaging and laser microirradiation to induce DNA lesions, we show that the local chromatin relaxation at DNA damage sites is regulated by PARP1 enzymatic activity. We also report that H1 is mobilized at DNA damage sites, but, since this mobilization is largely independent of poly(ADP-ribosyl)ation, it cannot solely explain the chromatin relaxation. Finally, we demonstrate the involvement of Alc1, a poly(ADP-ribose)- and ATP-dependent remodeler, in the chromatin-relaxation process. Deletion of Alc1 impairs chromatin relaxation after DNA damage, while its overexpression strongly enhances relaxation. Altogether our results identify Alc1 as an important player in the fast kinetics of the NAD+- and ATP-dependent chromatin relaxation upon DNA damage in vivo. PMID:27733626

  15. Mechanics of interstitial-lymphatic fluid transport: theoretical foundation and experimental validation.

    PubMed

    Swartz, M A; Kaipainen, A; Netti, P A; Brekken, C; Boucher, Y; Grodzinsky, A J; Jain, R K

    1999-12-01

    Interstitial fluid movement is intrinsically linked to lymphatic drainage. However, their relationship is poorly understood, and associated pathologies are mostly untreatable. In this work we test the hypothesis that bulk tissue fluid movement can be evaluated in situ and described by a linear biphasic theory which integrates the regulatory function of the lymphatics with the mechanical stresses of the tissue. To accomplish this, we develop a novel experimental and theoretical model using the skin of the mouse tail. We then use the model to demonstrate how interstitial-lymphatic fluid movement depends on a balance between the elasticity, hydraulic conductivity, and lymphatic conductance as well as to demonstrate how chronic swelling (edema) alters the equipoise between tissue fluid balance parameters. Specifically, tissue fluid equilibrium is perturbed with a continuous interstitial infusion of saline into the tip of the tail. The resulting gradients in tissue stress are measured in terms of interstitial fluid pressure using a servo-null system. These measurements are then fit to the theory to provide in vivo estimates of the tissue hydraulic conductivity, elastic modulus, and overall resistance to lymphatic drainage. Additional experiments are performed on edematous tails to show that although chronic swelling causes an increase in the hydraulic conductivity, its greatly increased distensibility (due to matrix remodeling) dampens the driving forces for fluid movement and leads to fluid stagnation. This model is useful for examining potential treatments for edema and lymphatic disorders as well as substances which may alter tissue fluid balance and/or lymphatic drainage.

  16. Sensitivity analysis of near-infrared functional lymphatic imaging

    NASA Astrophysics Data System (ADS)

    Weiler, Michael; Kassis, Timothy; Dixon, J. Brandon

    2012-06-01

    Near-infrared imaging of lymphatic drainage of injected indocyanine green (ICG) has emerged as a new technology for clinical imaging of lymphatic architecture and quantification of vessel function, yet the imaging capabilities of this approach have yet to be quantitatively characterized. We seek to quantify its capabilities as a diagnostic tool for lymphatic disease. Imaging is performed in a tissue phantom for sensitivity analysis and in hairless rats for in vivo testing. To demonstrate the efficacy of this imaging approach to quantifying immediate functional changes in lymphatics, we investigate the effects of a topically applied nitric oxide (NO) donor glyceryl trinitrate ointment. Premixing ICG with albumin induces greater fluorescence intensity, with the ideal concentration being 150 μg/mL ICG and 60 g/L albumin. ICG fluorescence can be detected at a concentration of 150 μg/mL as deep as 6 mm with our system, but spatial resolution deteriorates below 3 mm, skewing measurements of vessel geometry. NO treatment slows lymphatic transport, which is reflected in increased transport time, reduced packet frequency, reduced packet velocity, and reduced effective contraction length. NIR imaging may be an alternative to invasive procedures measuring lymphatic function in vivo in real time.

  17. FOXC2 and fluid shear stress stabilize postnatal lymphatic vasculature

    PubMed Central

    Sabine, Amélie; Bovay, Esther; Demir, Cansaran Saygili; Kimura, Wataru; Jaquet, Muriel; Agalarov, Yan; Zangger, Nadine; Scallan, Joshua P.; Graber, Werner; Gulpinar, Elgin; Kwak, Brenda R.; Mäkinen, Taija; Martinez-Corral, Inés; Ortega, Sagrario; Delorenzi, Mauro; Kiefer, Friedemann; Davis, Michael J.; Djonov, Valentin; Miura, Naoyuki; Petrova, Tatiana V.

    2015-01-01

    Biomechanical forces, such as fluid shear stress, govern multiple aspects of endothelial cell biology. In blood vessels, disturbed flow is associated with vascular diseases, such as atherosclerosis, and promotes endothelial cell proliferation and apoptosis. Here, we identified an important role for disturbed flow in lymphatic vessels, in which it cooperates with the transcription factor FOXC2 to ensure lifelong stability of the lymphatic vasculature. In cultured lymphatic endothelial cells, FOXC2 inactivation conferred abnormal shear stress sensing, promoting junction disassembly and entry into the cell cycle. Loss of FOXC2-dependent quiescence was mediated by the Hippo pathway transcriptional coactivator TAZ and, ultimately, led to cell death. In murine models, inducible deletion of Foxc2 within the lymphatic vasculature led to cell-cell junction defects, regression of valves, and focal vascular lumen collapse, which triggered generalized lymphatic vascular dysfunction and lethality. Together, our work describes a fundamental mechanism by which FOXC2 and oscillatory shear stress maintain lymphatic endothelial cell quiescence through intercellular junction and cytoskeleton stabilization and provides an essential link between biomechanical forces and endothelial cell identity that is necessary for postnatal vessel homeostasis. As FOXC2 is mutated in lymphedema-distichiasis syndrome, our data also underscore the role of impaired mechanotransduction in the pathology of this hereditary human disease. PMID:26389677

  18. Sensitivity analysis of near-infrared functional lymphatic imaging

    PubMed Central

    Weiler, Michael; Kassis, Timothy

    2012-01-01

    Abstract. Near-infrared imaging of lymphatic drainage of injected indocyanine green (ICG) has emerged as a new technology for clinical imaging of lymphatic architecture and quantification of vessel function, yet the imaging capabilities of this approach have yet to be quantitatively characterized. We seek to quantify its capabilities as a diagnostic tool for lymphatic disease. Imaging is performed in a tissue phantom for sensitivity analysis and in hairless rats for in vivo testing. To demonstrate the efficacy of this imaging approach to quantifying immediate functional changes in lymphatics, we investigate the effects of a topically applied nitric oxide (NO) donor glyceryl trinitrate ointment. Premixing ICG with albumin induces greater fluorescence intensity, with the ideal concentration being 150  μg/mL ICG and 60  g/L albumin. ICG fluorescence can be detected at a concentration of 150  μg/mL as deep as 6 mm with our system, but spatial resolution deteriorates below 3 mm, skewing measurements of vessel geometry. NO treatment slows lymphatic transport, which is reflected in increased transport time, reduced packet frequency, reduced packet velocity, and reduced effective contraction length. NIR imaging may be an alternative to invasive procedures measuring lymphatic function in vivo in real time. PMID:22734775

  19. Lymphatic Vessels, Inflammation, and Immunity in Skin Cancer.

    PubMed

    Lund, Amanda W; Medler, Terry R; Leachman, Sancy A; Coussens, Lisa M

    2016-01-01

    Skin is a highly ordered immune organ that coordinates rapid responses to external insult while maintaining self-tolerance. In healthy tissue, lymphatic vessels drain fluid and coordinate local immune responses; however, environmental factors induce lymphatic vessel dysfunction, leading to lymph stasis and perturbed regional immunity. These same environmental factors drive the formation of local malignancies, which are also influenced by local inflammation. Herein, we discuss clinical and experimental evidence supporting the tenet that lymphatic vessels participate in regulation of cutaneous inflammation and immunity, and are important contributors to malignancy and potential biomarkers and targets for immunotherapy. The tumor microenvironment and tumor-associated inflammation are now appreciated not only for their role in cancer progression but also for their response to therapy. The lymphatic vasculature is a less-appreciated component of this microenvironment that coordinates local inflammation and immunity and thereby critically shapes local responses. A mechanistic understanding of the complexities of lymphatic vessel function in the unique context of skin provides a model to understand how regional immune dysfunction drives cutaneous malignancies, and as such lymphatic vessels represent a biomarker of cutaneous immunity that may provide insight into cancer prognosis and effective therapy. ©2015 American Association for Cancer Research.

  20. SIZ1 regulation of phosphate starvation-induced root architecture remodeling involves the control of auxin accumulation.

    PubMed

    Miura, Kenji; Lee, Jiyoung; Gong, Qingqiu; Ma, Shisong; Jin, Jing Bo; Yoo, Chan Yul; Miura, Tomoko; Sato, Aiko; Bohnert, Hans J; Hasegawa, Paul M

    2011-02-01

    Phosphate (Pi) limitation causes plants to modulate the architecture of their root systems to facilitate the acquisition of Pi. Previously, we reported that the Arabidopsis (Arabidopsis thaliana) SUMO E3 ligase SIZ1 regulates root architecture remodeling in response to Pi limitation; namely, the siz1 mutations cause the inhibition of primary root (PR) elongation and the promotion of lateral root (LR) formation. Here, we present evidence that SIZ1 is involved in the negative regulation of auxin patterning to modulate root system architecture in response to Pi starvation. The siz1 mutations caused greater PR growth inhibition and LR development of seedlings in response to Pi limitation. Similar root phenotypes occurred if Pi-deficient wild-type seedlings were supplemented with auxin. N-1-Naphthylphthalamic acid, an inhibitor of auxin efflux activity, reduced the Pi starvation-induced LR root formation of siz1 seedlings to a level equivalent to that seen in the wild type. Monitoring of the auxin-responsive reporter DR5::uidA indicated that auxin accumulates in PR tips at early stages of the Pi starvation response. Subsequently, DR5::uidA expression was observed in the LR primordia, which was associated with LR elongation. The time-sequential patterning of DR5::uidA expression occurred earlier in the roots of siz1 as compared with the wild type. In addition, microarray analysis revealed that several other auxin-responsive genes, including genes involved in cell wall loosening and biosynthesis, were up-regulated in siz1 relative to wild-type seedlings in response to Pi starvation. Together, these results suggest that SIZ1 negatively regulates Pi starvation-induced root architecture remodeling through the control of auxin patterning.

  1. Fluoxetine induces input-specific hippocampal dendritic spine remodeling along the septotemporal axis in adulthood and middle age.

    PubMed

    McAvoy, Kathleen; Russo, Craig; Kim, Shannen; Rankin, Genelle; Sahay, Amar

    2015-11-01

    Fluoxetine, a selective serotonin-reuptake inhibitor (SSRI), is known to induce structural rearrangements and changes in synaptic transmission in hippocampal circuitry. In the adult hippocampus, structural changes include neurogenesis, dendritic, and axonal plasticity of pyramidal and dentate granule neurons, and dedifferentiation of dentate granule neurons. However, much less is known about how chronic fluoxetine affects these processes along the septotemporal axis and during the aging process. Importantly, studies documenting the effects of fluoxetine on density and distribution of spines along different dendritic segments of dentate granule neurons and CA1 pyramidal neurons along the septotemporal axis of hippocampus in adulthood and during aging are conspicuously absent. Here, we use a transgenic mouse line in which mature dentate granule neurons and CA1 pyramidal neurons are genetically labeled with green fluorescent protein (GFP) to investigate the effects of chronic fluoxetine treatment (18 mg/kg/day) on input-specific spine remodeling and mossy fiber structural plasticity in the dorsal and ventral hippocampus in adulthood and middle age. In addition, we examine levels of adult hippocampal neurogenesis, maturation state of dentate granule neurons, neuronal activity, and glutamic acid decarboxylase-67 expression in response to chronic fluoxetine in adulthood and middle age. Our studies reveal that while chronic fluoxetine fails to augment adult hippocampal neurogenesis in middle age, the middle-aged hippocampus retains high sensitivity to changes in the dentate gyrus (DG) such as dematuration, hypoactivation, and increased glutamic acid decarboxylase 67 (GAD67) expression. Interestingly, the middle-aged hippocampus shows greater sensitivity to fluoxetine-induced input-specific synaptic remodeling than the hippocampus in adulthood with the stratum-oriens of CA1 exhibiting heightened structural plasticity. The input-specific changes and circuit

  2. Fluoxetine induces input-specific hippocampal dendritic spine remodeling along the septo-temporal axis in adulthood and middle age

    PubMed Central

    McAvoy, Kathleen; Russo, Craig; Kim, Shannen; Rankin, Genelle; Sahay, Amar

    2015-01-01

    Fluoxetine, a selective serotonin-reuptake inhibitor (SSRI), is known to induce structural rearrangements and changes in synaptic transmission in hippocampal circuitry. In the adult hippocampus, structural changes include neurogenesis, dendritic and axonal plasticity of pyramidal and dentate granule neurons, and dedifferentiation of dentate granule neurons. However, much less is known about how chronic fluoxetine affects these processes along the septo-temporal axis and during the aging process. Importantly, studies documenting the effects of fluoxetine on density and distribution of spines along different dendritic segments of dentate granule neurons and CA1 pyramidal neurons along the septo-temporal axis of hippocampus in adulthood and during aging are conspicuously absent. Here, we use a transgenic mouse line in which mature dentate granule neurons and CA1 pyramidal neurons are genetically labeled with green fluorescent protein (GFP) to investigate the effects of chronic fluoxetine treatment (18mg/kg/day) on input-specific spine remodeling and mossy fiber structural plasticity in the dorsal and ventral hippocampus in adulthood and middle age. In addition, we examine levels of adult hippocampal neurogenesis, maturation state of dentate granule neurons, neuronal activity and glutamic acid decarboxylase-67 expression in response to chronic fluoxetine in adulthood and middle age. Our studies reveal that while chronic fluoxetine fails to augment adult hippocampal neurogenesis in middle age, the middle-aged hippocampus retains high sensitivity to changes in the dentate gyrus (DG) such as dematuration, hypoactivation, and increased glutamic acid decarboxylase 67 (GAD67) expression. Interestingly, the middle-aged hippocampus shows greater sensitivity to fluoxetine-induced input-specific synaptic remodeling than the hippocampus in adulthood with the stratum-oriens of CA1 exhibiting heightened structural plasticity. The input-specific changes and circuit

  3. Impact of Leucine Supplementation on Exercise Training Induced Anti-Cardiac Remodeling Effect in Heart Failure Mice

    PubMed Central

    de Moraes, Wilson Max Almeida Monteiro; Melara, Thaís Plasti; de Souza, Pamella Ramona Moraes; de Salvi Guimarães, Fabiana; Bozi, Luiz Henrique Marchesi; Brum, Patricia Chakur; Medeiros, Alessandra

    2015-01-01

    Leucine supplementation potentiates the effects of aerobic exercise training (AET) on skeletal muscle; however, its potential effects associated with AET on cardiac muscle have not been clarified yet. We tested whether leucine supplementation would potentiate the anti-cardiac remodeling effect of AET in a genetic model of sympathetic hyperactivity-induced heart failure in mice (α2A/α2CARKO). Mice were assigned to five groups: wild type mice treated with placebo and sedentary (WT, n = 11), α2A/α2CARKO treated with placebo and sedentary (KO, n = 9), α2A/α2CARKO treated with leucine and sedentary (KOL, n = 11), α2A/α2CARKO treated with placebo and AET (KOT, n = 12) or α2A/α2CARKO treated with leucine and AET (KOLT, n = 12). AET consisted of four weeks on a treadmill with 60 min sessions (six days/week, 60% of maximal speed) and administration by gavage of leucine (1.35 g/kg/day) or placebo (distilled water). The AET significantly improved exercise capacity, fractional shortening and re-established cardiomyocytes’ diameter and collagen fraction in KOT. Additionally, AET significantly prevented the proteasome hyperactivity, increased misfolded proteins and HSP27 expression. Isolated leucine supplementation displayed no effect on cardiac function and structure (KOL), however, when associated with AET (KOLT), it increased exercise tolerance to a higher degree than isolated AET (KOT) despite no additional effects on AET induced anti-cardiac remodeling. Our results provide evidence for the modest impact of leucine supplementation on cardiac structure and function in exercised heart failure mice. Leucine supplementation potentiated AET effects on exercise tolerance, which might be related to its recognized impact on skeletal muscle. PMID:25988767

  4. Impact of leucine supplementation on exercise training induced anti-cardiac remodeling effect in heart failure mice.

    PubMed

    de Moraes, Wilson Max Almeida Monteiro; Melara, Thaís Plasti; de Souza, Pamella Ramona Moraes; Guimarães, Fabiana de Salvi; Bozi, Luiz Henrique Marchesi; Brum, Patricia Chakur; Medeiros, Alessandra

    2015-05-15

    Leucine supplementation potentiates the effects of aerobic exercise training (AET) on skeletal muscle; however, its potential effects associated with AET on cardiac muscle have not been clarified yet. We tested whether leucine supplementation would potentiate the anti-cardiac remodeling effect of AET in a genetic model of sympathetic hyperactivity-induced heart failure in mice (α2A/α2CARKO). Mice were assigned to five groups: wild type mice treated with placebo and sedentary (WT, n = 11), α2A/α2CARKO treated with placebo and sedentary (KO, n = 9), α2A/α2CARKO treated with leucine and sedentary (KOL, n = 11), α2A/α2CARKO treated with placebo and AET (KOT, n = 12) or α2A/α2CARKO treated with leucine and AET (KOLT, n = 12). AET consisted of four weeks on a treadmill with 60 min sessions (six days/week, 60% of maximal speed) and administration by gavage of leucine (1.35 g/kg/day) or placebo (distilled water). The AET significantly improved exercise capacity, fractional shortening and re-established cardiomyocytes' diameter and collagen fraction in KOT. Additionally, AET significantly prevented the proteasome hyperactivity, increased misfolded proteins and HSP27 expression. Isolated leucine supplementation displayed no effect on cardiac function and structure (KOL), however, when associated with AET (KOLT), it increased exercise tolerance to a higher degree than isolated AET (KOT) despite no additional effects on AET induced anti-cardiac remodeling. Our results provide evidence for the modest impact of leucine supplementation on cardiac structure and function in exercised heart failure mice. Leucine supplementation potentiated AET effects on exercise tolerance, which might be related to its recognized impact on skeletal muscle.

  5. Targeting TRAF3IP2 by Genetic and Interventional Approaches Inhibits Ischemia/Reperfusion-induced Myocardial Injury and Adverse Remodeling.

    PubMed

    Erikson, John M; Valente, Anthony J; Mummidi, Srinivas; Kandikattu, Hemanth Kumar; DeMarco, Vincent G; Bender, Shawn B; Fay, William P; Siebenlist, Ulrich; Chandrasekar, Bysani

    2017-02-10

    Re-establishing blood supply is the primary goal for reducing myocardial injury in subjects with ischemic heart disease. Paradoxically, reperfusion results in nitroxidative stress and a marked inflammatory response in the heart. TRAF3IP2 (TRAF3 Interacting Protein 2; previously known as CIKS or Act1) is an oxidative stress-responsive cytoplasmic adapter molecule that is an upstream regulator of both IκB kinase (IKK) and c-Jun N-terminal kinase (JNK), and an important mediator of autoimmune and inflammatory responses. Here we investigated the role of TRAF3IP2 in ischemia/reperfusion (I/R)-induced nitroxidative stress, inflammation, myocardial dysfunction, injury, and adverse remodeling. Our data show that I/R up-regulates TRAF3IP2 expression in the heart, and its gene deletion, in a conditional cardiomyocyte-specific manner, significantly attenuates I/R-induced nitroxidative stress, IKK/NF-κB and JNK/AP-1 activation, inflammatory cytokine, chemokine, and adhesion molecule expression, immune cell infiltration, myocardial injury, and contractile dysfunction. Furthermore, Traf3ip2 gene deletion blunts adverse remodeling 12 weeks post-I/R, as evidenced by reduced hypertrophy, fibrosis, and contractile dysfunction. Supporting the genetic approach, an interventional approach using ultrasound-targeted microbubble destruction-mediated delivery of phosphorothioated TRAF3IP2 antisense oligonucleotides into the LV in a clinically relevant time frame significantly inhibits TRAF3IP2 expression and myocardial injury in wild type mice post-I/R. Furthermore, ameliorating myocardial damage by targeting TRAF3IP2 appears to be more effective to inhibiting its downstream signaling intermediates NF-κB and JNK. Therefore, TRAF3IP2 could be a potential therapeutic target in ischemic heart disease.

  6. The potential effect of the angiotensin II receptor blocker telmisartan in regulating OVA-induced airway remodeling in experimental rats.

    PubMed

    Abdel-Fattah, Maha M; Salama, Abeer A A; Shehata, Basim A; Ismaiel, Ismaiel E

    2015-10-01

    Bronchial asthma is a true ascending clinical problem. Angiotensin II is now accused to be potentially implicated in its pathogenesis, being a potent pro-inflammatory mediator with remodeling effects. This study aims to evaluate the possible protective effect of telmisartan, an angiotensin II receptor blocker, on experimentally-induced bronchial asthma. Animals were divided into 5 groups; a normal control group, an asthma control group, a reference treatment group, receiving dexamethasone, and two treatment groups, receiving telmisartan in two dose levels. Bronchial asthma was induced by intraperitoneal sensitization followed by intranasal challenge with ovalbumin (OVA). Test agents were administered prior to each intranasal OVA challenge. Lung function tests, namely tidal volume (TV) and peak expiratory flow rate (PEF) were assessed 1h after the last challenge. One day after the last challenge, absolute eosinophil counts (AEC) in blood and bronchoalveolar lavage fluids (BALF) were assessed. Serum immunoglobulin E (IgE) as well as BALF total nitrate/nitrite (NOx) were assessed. Oxidative and inflammatory biomarkers, namely lung tissue superoxide dismutase (SOD), glutathione reduced (GSH), tumor necrosis factor-alpha (TNF-α) and interleukin-5 (IL-5), were also assessed, in addition to histopathological study. Telmisartan administration in both doses significantly improved TV, PEF, AEC, IgE, NOx, GSH, SOD, TNF-α and IL-5 values compared to asthma control values. Histopathological study strongly supported the results of biochemical estimations, particularly regarding airway remodeling. These results suggest that telmisartan may have potential protecting effects against experimental bronchial asthma, probably due to its bronchodilator, antioxidant and anti-inflammatory effects. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  7. Sensitivity analysis of near-infrared functional lymphatic imaging

    NASA Astrophysics Data System (ADS)

    Weiler, Michael; Kassis, Timothy; Dixon, J. Brandon

    2012-03-01

    Background - Near-infrared (NIR) imaging of lymphatic drainage of injected indocyanine green (ICG) has emerged as a new technology for clinical imaging of lymphatic architecture and quantification of vessel function, offering better spatial and temporal resolution than competing imaging modalities. While NIR lymphatic imaging has begun to be reported in the literature, the technology is still in its infancy and its imaging capabilities have yet to be quantitatively characterized. The objective of this study, therefore, was to characterize the parameters of NIR lymphatic imaging to quantify its capabilities as a diagnostic tool for evaluating lymphatic disease. Methods - An NIR imaging system was developed using a laser diode for excitation, ICG as a fluorescent agent, and a CCD camera to detect emission. A tissue phantom with mock lymphatic vessels of known depths and diameters was used as an alternative to in vivo lymphatic vessels due to the greater degree of control with the phantom. Results and Conclusions - When dissolved in an albumin physiological salt solution (APSS) to mimic interstitial fluid, ICG experiences shifts in the excitation/emission wavelengths such that it is maximally excited at 805nm and produces peak fluorescence at 840nm. Premixing ICG with albumin induces greater fluorescence intensity, with the ideal concentration being: 900μM (60g/L) albumin and 193.5μM (150μg/mL) ICG. ICG fluorescence can be detected as deep as 6mm, but spatial resolution deteriorates severely below 3mm, thus skewing vessel geometry measurements. ICG packet travel, a common measure of lymphatic transport, can be detected as deep as 5mm.

  8. Postnatal Deletion of Podoplanin in Lymphatic Endothelium Results in Blood Filling of the Lymphatic System and Impairs Dendritic Cell Migration to Lymph Nodes.

    PubMed

    Bianchi, Roberta; Russo, Erica; Bachmann, Samia B; Proulx, Steven T; Sesartic, Marko; Smaadahl, Nora; Watson, Steve P; Buckley, Christopher D; Halin, Cornelia; Detmar, Michael

    2017-01-01

    The lymphatic vascular system exerts major physiological functions in the transport of interstitial fluid from peripheral tissues back to the blood circulation and in the trafficking of immune cells to lymph nodes. Previous studies in global constitutive knockout mice for the lymphatic transmembrane molecule podoplanin reported perinatal lethality and a complex phenotype with lung abnormalities, cardiac defects, lymphedema, blood-filled lymphatic vessels, and lack of lymph node organization, reflecting the importance of podoplanin expression not only by the lymphatic endothelium but also by a variety of nonendothelial cell types. Therefore, we aimed to dissect the specific role of podoplanin expressed by adult lymphatic vessels. We generated an inducible, lymphatic-specific podoplanin knockout mouse model (Pdpn(ΔLEC)) and induced gene deletion postnatally. Pdpn(ΔLEC) mice were viable, and their lymphatic vessels appeared morphologically normal with unaltered fluid drainage function. Intriguingly, Pdpn(ΔLEC) mice had blood-filled lymph nodes and vessels, most frequently in the neck and axillary region, and displayed a blood-filled thoracic duct, suggestive of retrograde filling of blood from the blood circulation into the lymphatic system. Histological and fluorescence-activated cell sorter analyses revealed normal lymph node organization with the presence of erythrocytes within lymph node lymphatic vessels but not surrounding high endothelial venules. Moreover, fluorescein isothiocyanate painting experiments revealed reduced dendritic cell migration to lymph nodes in Pdpn(ΔLEC) mice. These results reveal an important role of podoplanin expressed by lymphatic vessels in preventing postnatal blood filling of the lymphatic vascular system and in contributing to efficient dendritic cell migration to the lymph nodes. © 2016 American Heart Association, Inc.

  9. Mapping superficial lymphatic territories in the rabbit.

    PubMed

    Soto-Miranda, Miguel A; Suami, Hiroo; Chang, David W

    2013-06-01

    Little is known about the anatomy of the lymphatic system in the rabbit with regard to relationships between the lymphatic vessel and lymph node. According to our previous studies in human cadavers and canines, the superficial lymphatic system could be divided into lymphatic territories. The aim of this study was to completely map the superficial lymphatic system in the rabbit. We used our microinjection technique and histological analysis for dissecting studies and recently developed indocyanine green (ICG) fluorescent lymphography for demonstrating dynamic lymph flow in living rabbits. Real-time ICG fluorescent lymphography was performed in two living New Zealand White rabbits, and direct dye microinjection of the lymphatic vessels was performed in eight dead rabbits. To assess the relationships between the vascular and lymphatic systems in rabbits, we performed radiocontrast injection into arteries in two dead rabbits prior to the lymphatic injection. The ICG fluorescent lymphography revealed eight lymphatic territories in the preauricular, submandibular, root of the lateral neck, axillary, lumbar, inguinal, root of the tail, and popliteal regions. We injected blue acrylic dye into every lymphatic vessel 0.1 mm in diameter or larger. We then dissected and chased the stained lymphatic vessels proximally until the vessels connected to the first tier lymph node. This procedure was repeated throughout the body until all the relationships between the lymphatic vessels and lymph nodes were defined. The lymphatic system of the rabbit could be defined as eight lymphatic territories, each with its own lymphatic vessels and lymph node.

  10. Endogenous TNFα orchestrates the trafficking of neutrophils into and within lymphatic vessels during acute inflammation

    PubMed Central

    Arokiasamy, Samantha; Zakian, Christian; Dilliway, Jessica; Wang, Wen; Nourshargh, Sussan; Voisin, Mathieu-Benoit

    2017-01-01

    Neutrophils are recognised to play a pivotal role at the interface between innate and acquired immunities following their recruitment to inflamed tissues and lymphoid organs. While neutrophil trafficking through blood vessels has been extensively studied, the molecular mechanisms regulating their migration into the lymphatic system are still poorly understood. Here, we have analysed neutrophil-lymphatic vessel interactions in real time and in vivo using intravital confocal microscopy applied to inflamed cremaster muscles. We show that antigen sensitisation of the tissues induces a rapid but transient entry of tissue-infiltrated neutrophils into lymphatic vessels and subsequent crawling along the luminal side of the lymphatic endothelium. Interestingly, using mice deficient in both TNF receptors p55 and p75, chimeric animals and anti-TNFα antibody blockade we demonstrate that tissue-release of TNFα governs both neutrophil migration through the lymphatic endothelium and luminal crawling. Mechanistically, we show that TNFα primes directly the neutrophils to enter the lymphatic vessels in a strictly CCR7-dependent manner; and induces ICAM-1 up-regulation on lymphatic vessels, allowing neutrophils to crawl along the lumen of the lymphatic endothelium in an ICAM-1/MAC-1-dependent manner. Collectively, our findings demonstrate a new role for TNFα as a key regulator of neutrophil trafficking into and within lymphatic system in vivo. PMID:28287124

  11. Endogenous TNFα orchestrates the trafficking of neutrophils into and within lymphatic vessels during acute inflammation.

    PubMed

    Arokiasamy, Samantha; Zakian, Christian; Dilliway, Jessica; Wang, Wen; Nourshargh, Sussan; Voisin, Mathieu-Benoit

    2017-03-13

    Neutrophils are recognised to play a pivotal role at the interface between innate and acquired immunities following their recruitment to inflamed tissues and lymphoid organs. While neutrophil trafficking through blood vessels has been extensively studied, the molecular mechanisms regulating their migration into the lymphatic system are still poorly understood. Here, we have analysed neutrophil-lymphatic vessel interactions in real time and in vivo using intravital confocal microscopy applied to inflamed cremaster muscles. We show that antigen sensitisation of the tissues induces a rapid but transient entry of tissue-infiltrated neutrophils into lymphatic vessels and subsequent crawling along the luminal side of the lymphatic endothelium. Interestingly, using mice deficient in both TNF receptors p55 and p75, chimeric animals and anti-TNFα antibody blockade we demonstrate that tissue-release of TNFα governs both neutrophil migration through the lymphatic endothelium and luminal crawling. Mechanistically, we show that TNFα primes directly the neutrophils to enter the lymphatic vessels in a strictly CCR7-dependent manner; and induces ICAM-1 up-regulation on lymphatic vessels, allowing neutrophils to crawl along the lumen of the lymphatic endothelium in an ICAM-1/MAC-1-dependent manner. Collectively, our findings demonstrate a new role for TNFα as a key regulator of neutrophil trafficking into and within lymphatic system in vivo.

  12. Krypton laser photocoagulation induces retinal vascular remodeling rather than choroidal neovascularization.

    PubMed

    Behar-Cohen, F; Benezra, D; Soubrane, G; Jonet, L; Jeanny, J C

    2006-08-01

    photocoagulation site and around it. Confocal microscopy demonstrates that the vessels throughout the path lesion are located within the neuroretina while in the choroid (after separation of the neural retina) only GFAP-positive but no lectin-positive cells can be seen. The involvement of infiltrating inflammatory cells in these remodeling and healing processes remained minimal throughout the study period. During the 4 weeks following krypton laser photocoagulation in the mouse eye, processes of wound healing and remodeling appear to be driven by cells (and vessels) originating from the retina.

  13. Surgical thoracic sympathectomy induces structural and biomechanical remodeling of the thoracic aorta in a porcine model.

    PubMed

    Angouras, Dimitrios C; Dosios, Theodosios J; Dimitriou, Constantinos A; Chamogeorgakis, Themistocles P; Rokkas, Chris K; Manos, Themistoklis A; Sokolis, Dimitrios P

    2012-01-01

    Sympathetic innervation exerts marked effects on vascular smooth muscle cells, including a short-term homeostatic (vasoconstrictor) and a direct trophic action promoting differentiation. However, the role of sympathetic nervous system in long-term structural and functional modulation of the aortic wall is yet undefined. Six Landrace pigs underwent bilateral thoracic sympathectomy from the stellate to T8 ganglion, whereas 10 pigs underwent sham operation. Animals were sacrificed 3 mo postoperatively. Histometrical examination was performed on specimens from the thoracic (TA) and abdominal aorta (AA) utilizing an image-processing system. A uniaxial tensile tester was utilized for biomechanical evaluation; parameters of extensibility, strength, and stiffness of aortic tissue were calculated. Structural aortic remodeling of sympathectomized animals was observed, including increased inner aortic diameter in TA (15.3 ± 0.4 versus 10.4 ± 0.2 mm, P < 0.001) and AA (6.7 ± 0.3 versus 5.3 ± 0.2 mm, P = 0.002), and increased wall thickness in TA (2.0 ± 0.1 versus 1.6 ± 0.1 mm, P < 0.001) but not AA. Microscopic image analysis revealed increased elastin (TA: 50.1 ± 1.1 versus 29.7% ± 0.6%, P < 0.001; AA: 20.4 ± 2.1 versus 16.3% ± 0.6%, P = 0.03) and collagen density (only in TA: 22.0 ± 0.9 versus 15.4% ± 0.5%, P < 0.001), and decreased smooth muscle density (TA: 27.6 ± 1.3 versus 54.9% ± 0.7%, P < 0.001; AA: 57.2 ± 1.5 versus 63.4% ± 0.8%, P < 0.001). Sophisticated biomechanical analysis demonstrated that following sympathectomy, TA was equally extensible but manifested augmented strength (1344 ± 73 versus 1071 ± 52 kPa, P = 0.004) and stiffness (6738 ± 478 versus 5026 ± 273 kPa, P = 0.003), in accordance with extracellular matrix protein accumulation in that region. Differences in the AA were non-significant. Chronic thoracic sympathetic denervation causes significant structural and biomechanical remodeling of the thoracic aorta. Possible clinical

  14. Lymphatic Biodistribution of Polylactide Nanoparticles

    PubMed Central

    Chaney, Eric J.; Tang, Li; Tong, Rong; Cheng, Jianjun; Boppart, Stephen A.

    2013-01-01

    Tumor metastases occur through both the cardiovascular and lymphatic circulations. However, the majority of nanoparticle biodistribution studies have been focused on the cardiovascular circulation. In this study, we report the formulation of Cy5-labeled polylactide (Cy5-PLA) nanoparticles with controlled size and surface features and the subsequent evaluation of their lymphatic biodistribution. Cy5-PLA nanoparticles were formulated through Cy5/(BDI)ZnN(TMS)2-mediated [(BDI) = 2-((2,6-diisopropylphenyl) amido)-4-((2,6-diisopropylphenyl)-imino)-2-pentene] ring-opening polymerization of lactide followed by nanoprecipitation. Their lymphatic biodistribution was evaluated by using whole-body fluorescence imaging of nude mice and ex vivo fluorescence imaging of the resected organs. This technique has the potential for providing optical contrast and drug delivery through the lymphatic circulation for the treatment of metastatic cancer. PMID:20487681

  15. Aberrant lung remodeling in a mouse model of surfactant dysregulation induced by modulation of the Abca3 gene✩

    PubMed Central

    Beers, Michael F.; Knudsen, Lars; Tomer, Yaniv; Maronn, Julian; Zhao, Ming; Ochs, Matthias; Mulugeta, Surafel

    2017-01-01

    vulnerable to exogenous injury. Three weeks following intratracheal bleomycin challenge, mAbca3–rNeo mice demonstrated allele-dependent susceptibility to bleomycin including enhanced weight loss, augmented airspace destruction, and increased fibrosis. Removal of the rNeo cassette from mAbca3 alleles resulted in restoration of BAL PL content to wild-type levels and an absence of changes in lung histology up to 32 weeks of age. These results support the importance of surfactant PL homeostasis as a susceptibility factor for both intrinsic and exogenously induced lung injury/remodeling. PMID:28034695

  16. Aberrant lung remodeling in a mouse model of surfactant dysregulation induced by modulation of the Abca3 gene.

    PubMed

    Beers, Michael F; Knudsen, Lars; Tomer, Yaniv; Maronn, Julian; Zhao, Ming; Ochs, Matthias; Mulugeta, Surafel

    2017-03-01

    were rendered more vulnerable to exogenous injury. Three weeks following intratracheal bleomycin challenge, mAbca3-rNeo mice demonstrated allele-dependent susceptibility to bleomycin including enhanced weight loss, augmented airspace destruction, and increased fibrosis. Removal of the rNeo cassette from mAbca3 alleles resulted in restoration of BAL PL content to wild-type levels and an absence of changes in lung histology up to 32 weeks of age. These results support the importance of surfactant PL homeostasis as a susceptibility factor for both intrinsic and exogenously induced lung injury/remodeling.

  17. Lidocaine Injections Targeting CA3 Hippocampus Impair Long-Term Spatial Memory and Prevent Learning-Induced Mossy Fiber Remodeling

    PubMed Central

    Holahan, Matthew R.; Routtenberg, Aryeh

    2010-01-01

    Learning a spatial location induces remodeling of the mossy fiber terminal field (MFTF) in the CA3 subfield of the dorsal hippocampus (Holahan et al., 2006; Ramirez-Amaya et al., 2001; Rekart et al., 2007a). These fibers appear to grow from the stratum lucidum (SL) into distal stratum oriens (dSO). Is this axonal growth dependent on ‘repeated and persistent’ neural activity in the CA3 region during training? To address this issue, we targeted local inactivation of the MFTF region in a post-training, consolidation paradigm. Male Wistar rats, bilaterally implanted with chronic indwelling cannulae aimed at the MFTF CA3 region, were trained on a hidden platform water maze task (10 trials per day for 5 days). Immediately after the 10th trial on each training day, rats were injected with lidocaine (4% w/V; 171 mM; n = 7) or phosphate-buffered saline (PBS; n = 7). Behavioral measures of latency, path length and thigmotaxis were recorded, as was directional heading. A retention test (probe trial) was given 7 days after the last training day and brains were subsequently processed for MFTF distribution (Timm’s stain) and cannula location. Lidocaine treatment was found to block the learning-associated structural remodeling of the MFTF that was reported previously and observed in the PBS-injected controls. During training, the lidocaine group showed elevated latencies and a misdirected heading to locate the platform on the first trial of each training day. On the 7-day retention probe trial, the lidocaine-injected group showed poor retention indicated by the absence of a search bias in the area where the platform had been located during training. These data suggest that reduction of neuronal activity in the CA3 region impairs long-term storage of spatial information. As this was associated with reduced MFTF structural remodeling, it provides initial anatomical and behavioral evidence for an activity – dependent, presynaptic growth model of memory. PMID:20865723

  18. A Plant Proteinase Inhibitor from Enterolobium contortisiliquum Attenuates Pulmonary Mechanics, Inflammation and Remodeling Induced by Elastase in Mice

    PubMed Central

    Theodoro-Júnior, Osmar Aparecido; Righetti, Renato Fraga; Almeida-Reis, Rafael; Martins-Oliveira, Bruno Tadeu; Oliva, Leandro Vilela; Prado, Carla Máximo; Saraiva-Romanholo, Beatriz Mangueira; Leick, Edna Aparecida; Pinheiro, Nathalia Montouro; Lobo, Yara Aparecida; Martins, Mílton de Arruda; Oliva, Maria Luiza Vilela; Tibério, Iolanda de Fátima Lopes Calvo

    2017-01-01

    Proteinase inhibitors have been associated with anti-inflammatory and antioxidant activities and may represent a potential therapeutic treatment for emphysema. Our aim was to evaluate the effects of a plant Kunitz proteinase inhibitor, Enterolobium contortisiliquum trypsin inhibitor (EcTI), on several aspects of experimental elastase-induced pulmonary inflammation in mice. C57/Bl6 mice were intratracheally administered elastase (ELA) or saline (SAL) and were treated intraperitoneally with EcTI (ELA-EcTI, SAL-EcTI) on days 1, 14 and 21. On day 28, pulmonary mechanics, exhaled nitric oxide (ENO) and number leucocytes in the bronchoalveolar lavage fluid (BALF) were evaluated. Subsequently, lung immunohistochemical staining was submitted to morphometry. EcTI treatment reduced responses of the mechanical respiratory system, number of cells in the BALF, and reduced tumor necrosis factor-α (TNF-α), matrix metalloproteinase-9 (MMP-9), matrix metalloproteinase-12 (MMP-12), tissue inhibitor of matrix metalloproteinase (TIMP-1), endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS)-positive cells and volume proportion of isoprostane, collagen and elastic fibers in the airways and alveolar walls compared with the ELA group. EcTI treatment reduced elastase induced pulmonary inflammation, remodeling, oxidative stress and mechanical alterations, suggesting that this inhibitor may be a potential therapeutic tool for chronic obstructive pulmonary disease (COPD) management. PMID:28216579

  19. A Plant Proteinase Inhibitor from Enterolobium contortisiliquum Attenuates Pulmonary Mechanics, Inflammation and Remodeling Induced by Elastase in Mice.

    PubMed

    Theodoro-Júnior, Osmar Aparecido; Righetti, Renato Fraga; Almeida-Reis, Rafael; Martins-Oliveira, Bruno Tadeu; Oliva, Leandro Vilela; Prado, Carla Máximo; Saraiva-Romanholo, Beatriz Mangueira; Leick, Edna Aparecida; Pinheiro, Nathalia Montouro; Lobo, Yara Aparecida; Martins, Mílton de Arruda; Oliva, Maria Luiza Vilela; Tibério, Iolanda de Fátima Lopes Calvo

    2017-02-14

    Proteinase inhibitors have been associated with anti-inflammatory and antioxidant activities and may represent a potential therapeutic treatment for emphysema. Our aim was to evaluate the effects of a plant Kunitz proteinase inhibitor, Enterolobium contortisiliquum trypsin inhibitor (EcTI), on several aspects of experimental elastase-induced pulmonary inflammation in mice. C57/Bl6 mice were intratracheally administered elastase (ELA) or saline (SAL) and were treated intraperitoneally with EcTI (ELA-EcTI, SAL-EcTI) on days 1, 14 and 21. On day 28, pulmonary mechanics, exhaled nitric oxide (ENO) and number leucocytes in the bronchoalveolar lavage fluid (BALF) were evaluated. Subsequently, lung immunohistochemical staining was submitted to morphometry. EcTI treatment reduced responses of the mechanical respiratory system, number of cells in the BALF, and reduced tumor necrosis factor-α (TNF-α), matrix metalloproteinase-9 (MMP-9), matrix metalloproteinase-12 (MMP-12), tissue inhibitor of matrix metalloproteinase (TIMP-1), endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS)-positive cells and volume proportion of isoprostane, collagen and elastic fibers in the airways and alveolar walls compared with the ELA group. EcTI treatment reduced elastase induced pulmonary inflammation, remodeling, oxidative stress and mechanical alterations, suggesting that this inhibitor may be a potential therapeutic tool for chronic obstructive pulmonary disease (COPD) management.

  20. S-diclofenac Protects against Doxorubicin-Induced Cardiomyopathy in Mice via Ameliorating Cardiac Gap Junction Remodeling

    PubMed Central

    Zhang, Huili; Zhang, Alian; Guo, Changfa; Shi, Chunzhi; Zhang, Yang; Liu, Qing; Sparatore, Anna; Wang, Changqian

    2011-01-01

    Hydrogen sulfide (H2S), as a novel gaseous mediator, plays important roles in mammalian cardiovascular tissues. In the present study, we investigated the cardioprotective effect of S-diclofenac (2-[(2,6-dichlorophenyl)amino] benzeneacetic acid 4-(3H-1,2,dithiol-3-thione-5-yl)phenyl ester), a novel H2S-releasing derivative of diclofenac, in a murine model of doxorubicin-induced cardiomyopathy. After a single dose injection of doxorubicin (15 mg/kg, i.p.), male C57BL/6J mice were given daily treatment of S-diclofenac (25 and 50 µmol/kg, i.p.), diclofenac (25 and 50 µmol/kg, i.p.), NaHS (50 µmol/kg, i.p.), or same volume of vehicle. The cardioprotective effect of S-diclofenac was observed after 14 days. It showed that S-diclofenac, but not diclofenac, dose-dependently inhibited the doxorubicin-induced downregulation of cardiac gap junction proteins (connexin 43 and connexin 45) and thus reversed the remodeling of gap junctions in hearts. It also dose-dependently suppressed doxorubicin-induced activation of JNK in hearts. Furthermore, S-diclofenac produced a dose-dependent anti-inflammatory and anti-oxidative effect in this model. As a result, S-diclofenac significantly attenuated doxorubicin-related cardiac injury and cardiac dysfunction, and improved the survival rate of mice with doxorubicin-induced cardiomyopathy. These effects of S-diclofenac were mimicked in large part by NaHS. Therefore, we propose that H2S released from S-diclofenac in vivo contributes to the protective effect in doxorubicin-induced cardiomyopathy. These data also provide evidence for a critical role of H2S in the pathogenesis of doxorubicin-induced cardiomyopathy. PMID:22039489

  1. PTP-PEST controls EphA3 activation and ephrin-induced cytoskeletal remodelling.

    PubMed

    Mansour, Mariam; Nievergall, Eva; Gegenbauer, Kristina; Llerena, Carmen; Atapattu, Lakmali; Hallé, Maxime; Tremblay, Michel L; Janes, Peter W; Lackmann, Martin

    2016-01-15

    Eph receptors and their corresponding membrane-bound ephrin ligands regulate cell positioning and establish tissue patterns during embryonic and oncogenic development. Emerging evidence suggests that assembly of polymeric Eph signalling clusters relies on cytoskeletal reorganisation and underlies regulation by protein tyrosine phosphatases (PTPs). PTP-PEST (also known as PTPN12) is a central regulator of actin cytoskeletal dynamics. Here, we demonstrate that an N-terminal fragment of PTP-PEST, generated through an ephrinA5-triggered and spatially confined cleavage mediated by caspase-3, attenuates EphA3 receptor activation and its internalisation. Isolation of EphA3 receptor signalling clusters within intact plasma membrane fragments obtained by detergent-free cell fractionation reveals that stimulation of cells with ephrin triggers effective recruitment of this catalytically active truncated form of PTP-PEST together with key cytoskeletal and focal adhesion proteins. Importantly, modulation of actin polymerisation using pharmacological and dominant-negative approaches affects EphA3 phosphorylation in a similar manner to overexpression of PTP-PEST. We conclude that PTP-PEST regulates EphA3 activation both by affecting cytoskeletal remodelling and through its direct action as a PTP controlling EphA3 phosphorylation, indicating its multifaceted regulation of Eph signalling. © 2016. Published by The Company of Biologists Ltd.

  2. Physically-Induced Cytoskeleton Remodeling of Cells in Three-Dimensional Culture

    PubMed Central

    Lee, Sheng-Lin; Nekouzadeh, Ali; Butler, Boyd; Pryse, Kenneth M.; McConnaughey, William B.; Nathan, Adam C.; Legant, Wesley R.; Schaefer, Pascal M.; Pless, Robert B.

    2012-01-01

    Characterizing how cells in three-dimensional (3D) environments or natural tissues respond to biophysical stimuli is a longstanding challenge in biology and tissue engineering. We demonstrate a strategy to monitor morphological and mechanical responses of contractile fibroblasts in a 3D environment. Cells responded to stretch through specific, cell-wide mechanisms involving staged retraction and reinforcement. Retraction responses occurred for all orientations of stress fibers and cellular protrusions relative to the stretch direction, while reinforcement responses, including extension of cellular processes and stress fiber formation, occurred predominantly in the stretch direction. A previously unreported role of F-actin clumps was observed, with clumps possibly acting as F-actin reservoirs for retraction and reinforcement responses during stretch. Responses were consistent with a model of cellular sensitivity to local physical cues. These findings suggest mechanisms for global actin cytoskeleton remodeling in non-muscle cells and provide insight into cellular responses important in pathologies such as fibrosis and hypertension. PMID:23300512

  3. From Slow to Fast: Hypogravity-Induced Remodeling of Muscle Fiber Myosin Phenotype

    PubMed Central

    Shenkman, B. S.

    2016-01-01

    Skeletal muscle consists of different fiber types arranged in a mosaic pattern. These fiber types are characterized by specific functional properties. Slow-type fibers demonstrate a high level of fatigue resistance and prolonged contraction duration, but decreased maximum contraction force and velocity. Fast-type fibers demonstrate high contraction force and velocity, but profound fatigability. During the last decades, it has been discovered that all these properties are determined by the predominance of slow or fast myosin-heavy-chain (MyHC) isoforms. It was observed that gravitational unloading during space missions and simulated microgravity in ground-based experiments leads to the transformation of some slow-twitch muscle fibers into fast-twitch ones due to changes in the patterns of MyHC gene expression in the postural soleus muscle. The present review covers the facts and mechanistic speculations regarding myosin phenotype remodeling under conditions of gravitational unloading. The review considers the neuronal mechanisms of muscle fiber control and molecular mechanisms of regulation of myosin gene expression, such as inhibition of the calcineurin/NFATc1 signaling pathway, epigenomic changes, and the behavior of specific microRNAs. In the final portion of the review, we discuss the adaptive role of myosin phenotype transformations. PMID:28050266

  4. Ultrasound Enhances Dentoalveolar Remodeling in an Ex Vivo Orthodontic, Ovariectomy-Induced Osteoporotic Model.

    PubMed

    Alhazmi, Khuloud S; El-Bialy, Tarek; Afify, Ahmed R; Merdad, Leena A; Hassan, Ali H

    2017-09-01

    The aim of the study was to investigate the effects of low-intensity pulsed ultrasound (LIPUS) on dentoalveolar structures during application of force to a cultured mandible slice taken from an ovariectomized rat model of osteoporosis. Rats were divided based on whether they had ovariectomy and/or LIPUS application into four groups: control osteoporosis group, control normal group, ultrasound-treated osteoporosis group and ultrasound-treated normal group. The mandibles were dissected, sliced and cultured before application of a 0.5-N force. Tissue specimens from five rats per group received LIPUS; the remaining rats served as untreated controls. Tissue sections were evaluated histologically and histomorphometrically. Osteoporosis significantly affected the alveolar bone without any effect on the dentin-pulp complex. LIPUS enhanced osteoporotic alveolar bone remodeling and increased cementum and predentin thickness. Furthermore, LIPUS application significantly increased odontoblast and periodontal ligament cell counts (p < 0.05) in both groups. Therefore, LIPUS enhances alveolar bone remolding and increases cementum and predentin formation in osteoporotic rat mandible slice organ cultures. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

  5. In vivo single branch axotomy induces GAP-43-dependent sprouting and synaptic remodeling in cerebellar cortex.

    PubMed

    Allegra Mascaro, Anna Letizia; Cesare, Paolo; Sacconi, Leonardo; Grasselli, Giorgio; Mandolesi, Georgia; Maco, Bohumil; Knott, Graham W; Huang, Lieven; De Paola, Vincenzo; Strata, Piergiorgio; Pavone, Francesco S

    2013-06-25

    Plasticity in the central nervous system in response to injury is a complex process involving axonal remodeling regulated by specific molecular pathways. Here, we dissected the role of growth-associated protein 43 (GAP-43; also known as neuromodulin and B-50) in axonal structural plasticity by using, as a model, climbing fibers. Single axonal branches were dissected by laser axotomy, avoiding collateral damage to the adjacent dendrite and the formation of a persistent glial scar. Despite the very small denervated area, the injured axons consistently reshape the connectivity with surrounding neurons. At the same time, adult climbing fibers react by sprouting new branches through the intact surroundings. Newly formed branches presented varicosities, suggesting that new axons were more than just exploratory sprouts. Correlative light and electron microscopy reveals that the sprouted branch contains large numbers of vesicles, with varicosities in the close vicinity of Purkinje dendrites. By using an RNA interference approach, we found that downregulating GAP-43 causes a significant increase in the turnover of presynaptic boutons. In addition, silencing hampers the generation of reactive sprouts. Our findings show the requirement of GAP-43 in sustaining synaptic stability and promoting the initiation of axonal regrowth.

  6. The Role of the Rho/ROCK Pathway in Ang II and TGF-β1-Induced Atrial Remodeling

    PubMed Central

    Lu, Gui-Hua; Xu, Cheng-Gui; Xu, Zhe; Tang, Kai; Cheng, Yun-Jiu; Gao, Xiu-Ren; Wu, Su-Hua

    2016-01-01

    Objectives To study the role of the Rho/ROCK pathway in Ang II and TGF-β1-induced atrial remodeling. Methods and Results A canine atrial fibrillation (AF) model was established by rapid atrial pacing (RAP) of the left atrium. The roles of TGF-β1, the RhoA/ROCK signaling pathway and connective tissue growth factor (CTGF) in atrial remodeling were studied via both in vitro and in vivo experiments. Each of the dogs that received RAP developed persistent AF within 4 weeks. The mRNA expression levels of TGF-β1 (1.32±0.38), Collagen-I(1.33±0.91), CTGF(5.83±3.71), RhoA(1.23±0.57) and ROCK-1 (1.02±0.27) in the left atrium were significantly increased following 4 weeks of RAP. Angiotensin II (Ang II) induced the proliferation of atrial fibroblasts and up-regulated the expression of both CTGF and ROCK-1 in a dose-dependent manner. Simvastatin and Y27632 reversed Ang II-induced CFs proliferation, as well as ROCK-1(0.89±0.05 and 1.27±0.03, respectively) and CTGF (0.87±0.04 and 0.91±0.02, respectively) expression. The expression mRNA of ROCK-1(1.74±0.13) and CTGF (2.28±0.11) can upregulated by TGF-β1, and down-regulated by Simvastatin (1.22±0.03 vs 2.27±0.11), Y27632 (1.01±0.04 vs 1.64±0.03), Los (1.04±0.11 vs 1.26±0.05), respectively. Losartan and Simvastatin attenuated the effects of TGF-β1, inhibited RhoA activity as opposed to RhoA protein expression. Y27632 had no effect on either the expression or the activity of RhoA. Conclusions The increased expression of profibrotic factors (CTGF, ROCK1 and Smad2/3) played an important role in our RAP-induced AF model. Increased atrial profibrotic factors involve the activation of either the TGF-β1/RhoA/ROCK-1 or the TGF-β1/Smad2/3 signaling pathway. PMID:27611832

  7. The Role of the Rho/ROCK Pathway in Ang II and TGF-β1-Induced Atrial Remodeling.

    PubMed

    Liu, Li-Juan; Yao, Feng-Juan; Lu, Gui-Hua; Xu, Cheng-Gui; Xu, Zhe; Tang, Kai; Cheng, Yun-Jiu; Gao, Xiu-Ren; Wu, Su-Hua

    2016-01-01

    To study the role of the Rho/ROCK pathway in Ang II and TGF-β1-induced atrial remodeling. A canine atrial fibrillation (AF) model was established by rapid atrial pacing (RAP) of the left atrium. The roles of TGF-β1, the RhoA/ROCK signaling pathway and connective tissue growth factor (CTGF) in atrial remodeling were studied via both in vitro and in vivo experiments. Each of the dogs that received RAP developed persistent AF within 4 weeks. The mRNA expression levels of TGF-β1 (1.32±0.38), Collagen-I(1.33±0.91), CTGF(5.83±3.71), RhoA(1.23±0.57) and ROCK-1 (1.02±0.27) in the left atrium were significantly increased following 4 weeks of RAP. Angiotensin II (Ang II) induced the proliferation of atrial fibroblasts and up-regulated the expression of both CTGF and ROCK-1 in a dose-dependent manner. Simvastatin and Y27632 reversed Ang II-induced CFs proliferation, as well as ROCK-1(0.89±0.05 and 1.27±0.03, respectively) and CTGF (0.87±0.04 and 0.91±0.02, respectively) expression. The expression mRNA of ROCK-1(1.74±0.13) and CTGF (2.28±0.11) can upregulated by TGF-β1, and down-regulated by Simvastatin (1.22±0.03 vs 2.27±0.11), Y27632 (1.01±0.04 vs 1.64±0.03), Los (1.04±0.11 vs 1.26±0.05), respectively. Losartan and Simvastatin attenuated the effects of TGF-β1, inhibited RhoA activity as opposed to RhoA protein expression. Y27632 had no effect on either the expression or the activity of RhoA. The increased expression of profibrotic factors (CTGF, ROCK1 and Smad2/3) played an important role in our RAP-induced AF model. Increased atrial profibrotic factors involve the activation of either the TGF-β1/RhoA/ROCK-1 or the TGF-β1/Smad2/3 signaling pathway.

  8. Lymphatic Regulation of Cellular Trafficking

    PubMed Central

    Jackson, David G.

    2016-01-01

    Lymphatic vessels play vital roles in immune surveillance and immune regulation by conveying antigen loaded dendritic cells, memory T cells, macrophages and neutrophils from the peripheral tissues to draining lymph nodes where they initiate as well as modify immune responses. Until relatively recently however, there was little understanding of how entry and migration through lymphatic vessels is organized or the specific molecular mechanisms that might be involved. Within the last decade, the situation has been transformed by an explosion of knowledge generated largely through the application of microscopic imaging, transgenic animals, specific markers and function blocking mAbs that is beginning to provide a rational conceptual framework. This article provides a critical review of the recent literature, highlighting seminal discoveries that have revealed the fascinating ultrastructure of leucocyte entry sites in lymphatic vessels, as well as generating controversies over the involvement of integrin adhesion, chemotactic and haptotactic mechanisms in DC entry under normal and inflamed conditions. It also discusses the major changes in lymphatic architecture that occur during inflammation and the different modes of leucocyte entry and trafficking within inflamed lymphatic vessels, as well as presenting a timely update on the likely role of hyaluronan and the major lymphatic endothelial hyaluronan receptor LYVE-1 in leucocyte transit. PMID:27808282

  9. Adipose tissue remodeling in late-lactation dairy cows during feed-restriction-induced negative energy balance.

    PubMed

    Contreras, G Andres; Thelen, Kyan; Schmidt, Sarah E; Strieder-Barboza, Clarissa; Preseault, Courtney L; Raphael, William; Kiupel, Matti; Caron, John; Lock, Adam L

    2016-12-01

    Excessive rates of demand lipolysis in the adipose tissue (AT) during periods of negative energy balance (NEB) are associated with increased susceptibility to disease and limited lactation performance. Lipolysis induces a remodeling process within AT that is characterized by an inflammatory response, cellular proliferation, and changes in the extracellular matrix (ECMT). The adipose tissue macrophage (ATM) is a key component of the inflammatory response. Infiltration of ATM-forming cellular aggregates was demonstrated in transition cows, suggesting that ATM trafficking and phenotype changes may be associated with disease. However, it is currently unknown if ATM infiltration occurs in dairy cows only during NEB states related to the transition period or also during NEB-induced lipolysis at other stages of lactation. The objective of this study was to evaluate changes in ATM trafficking and inflammatory phenotypes, and the expression of genetic markers of AT remodeling in healthy late-lactation cows during feed restriction-induced NEB. After a 14-d (d -14 to d -1) preliminary period, Holstein cows were randomly assigned to 1 of 2 feeding protocols, ad libitum (AL) or feed restriction (FR), for 4 d (d 1-4). Caloric intake was reduced in FR to achieve a targeted energy balance of -15 Mcal/d of net energy for lactation. Omental and subcutaneous AT samples were collected laparoscopically to harvest stromal vascular fraction (SVF) cells on d -3 and 4. The FR induced a NEB of -14.1±0.62 Mcal/d of net energy for lactation, whereas AL cows remained in positive energy balance (3.2±0.66 Mcal/d of NEL). The FR triggered a lipolytic response reflected in increased plasma nonesterified fatty acids (0.65±0.05 mEq/L on d 4), enhanced phosphorylation of hormone sensitive lipase, and reduced adipocyte diameter. Flow cytometry and immunohistochemistry analysis revealed that on d 4, FR cows had increased numbers of CD172a(+), an ATM (M1 and M2) surface marker, cells in SVF that were

  10. Sigma-1 receptor mediates cocaine-induced transcriptional regulation by recruiting chromatin-remodeling factors at the nuclear envelope.

    PubMed

    Tsai, Shang-Yi A; Chuang, Jian-Ying; Tsai, Meng-Shan; Wang, Xiao-Fei; Xi, Zheng-Xiong; Hung, Jan-Jong; Chang, Wen-Chang; Bonci, Antonello; Su, Tsung-Ping

    2015-11-24

    The sigma-1 receptor (Sig-1R) chaperone at the endoplasmic reticulum (ER) plays important roles in cellular regulation. Here we found a new function of Sig-1R, in that it translocates from the ER to the nuclear envelope (NE) to recruit chromatin-remodeling molecules and regulate the gene transcription thereof. Sig-1Rs mainly reside at the ER-mitochondrion interface. However, on stimulation by agonists such as cocaine, Sig-1Rs translocate from ER to the NE, where Sig-1Rs bind NE protein emerin and recruit chromatin-remodeling molecules, including lamin A/C, barrier-to-autointegration factor (BAF), and histone deacetylase (HDAC), to form a complex with the gene repressor specific protein 3 (Sp3). Knockdown of Sig-1Rs attenuates the complex formation. Cocaine was found to suppress the gene expression of monoamine oxidase B (MAOB) in the brain of wild-type but not Sig-1R knockout mouse. A single dose of cocaine (20 mg/kg) in rats suppresses the level of MAOB at nuclear accumbens without affecting the level of dopamine transporter. Daily injections of cocaine in rats caused behavioral sensitization. Withdrawal from cocaine in cocaine-sensitized rats induced an apparent time-dependent rebound of the MAOB protein level to about 200% over control on day 14 after withdrawal. Treatment of cocaine-withdrawn rats with the MAOB inhibitor deprenyl completely alleviated the behavioral sensitization to cocaine. Our results demonstrate a role of Sig-1R in transcriptional regulation and suggest cocaine may work through this newly discovered genomic action to achieve its addictive action. Results also suggest the MAOB inhibitor deprenyl as a therapeutic agent to block certain actions of cocaine during withdrawal.

  11. Ablation of IL-33 gene exacerbate myocardial remodeling in mice with heart failure induced by mechanical stress.

    PubMed

    Veeraveedu, Punniyakoti T; Sanada, Shoji; Okuda, Keiji; Fu, Hai Ying; Matsuzaki, Takashi; Araki, Ryo; Yamato, Masaki; Yasuda, Koubun; Sakata, Yasushi; Yoshimoto, Tomohiro; Minamino, Tetsuo

    2017-08-15

    ST2 is one of the interleukin (IL)-1 receptor family members comprising of membrane-bound (ST2L) and soluble (sST2) isoforms. Clinical trials have revealed that serum sST2 levels predict outcome in patient with myocardial infarction or chronic heart failure (HF). Meanwhile, we and others have reported that ablation of ST2 caused exaggerated cardiac remodeling in both ischemic and non-ischemic HF. Here, we tested whether IL-33, the ligand for ST2, protects myocardium against HF induced by mechanical overload using ligand specific knockout (IL-33(-/-)) mice. Transverse aortic constriction (TAC)/sham surgery were carried out in both IL-33 and WT-littermates. Echocardiographic measurements were performed at frequent interval during the study period. Heart was harvested for RNA and histological measurements. Following mechanical overload by TAC, myocardial mRNA expressions of Th1 cytokines, such as TNF-α were enhanced in IL-33(-/-) mice than in WT mice. After 8-weeks, IL-33(-/-) mice exhibited exacerbated left ventricular hypertrophy, increased chamber dilation, reduced fractional shortening, aggravated fibrosis, inflammation, and impaired survival compared with WT littermates. Accordingly, myocardial mRNA expressions of hypertrophic (c-Myc/BNP) molecular markers were also significantly enhanced in IL-33(-/-) mice than those in WT mice. We report for the first time that ablation of IL-33 directly and significantly leads to exacerbate cardiac remodeling with impaired cardiac function and survival upon mechanical stress. These data highlight the cardioprotective role of IL-33/ST2 system in the stressed myocardium and reveal a potential therapeutic role for IL-33 in non-ischemic HF. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Sigma-1 receptor mediates cocaine-induced transcriptional regulation by recruiting chromatin-remodeling factors at the nuclear envelope

    PubMed Central

    Tsai, Shang-Yi A.; Chuang, Jian-Ying; Tsai, Meng-Shan; Wang, Xiao-fei; Hung, Jan-Jong; Chang, Wen-Chang; Bonci, Antonello; Su, Tsung-Ping

    2015-01-01

    The sigma-1 receptor (Sig-1R) chaperone at the endoplasmic reticulum (ER) plays important roles in cellular regulation. Here we found a new function of Sig-1R, in that it translocates from the ER to the nuclear envelope (NE) to recruit chromatin-remodeling molecules and regulate the gene transcription thereof. Sig-1Rs mainly reside at the ER–mitochondrion interface. However, on stimulation by agonists such as cocaine, Sig-1Rs translocate from ER to the NE, where Sig-1Rs bind NE protein emerin and recruit chromatin-remodeling molecules, including lamin A/C, barrier-to-autointegration factor (BAF), and histone deacetylase (HDAC), to form a complex with the gene repressor specific protein 3 (Sp3). Knockdown of Sig-1Rs attenuates the complex formation. Cocaine was found to suppress the gene expression of monoamine oxidase B (MAOB) in the brain of wild-type but not Sig-1R knockout mouse. A single dose of cocaine (20 mg/kg) in rats suppresses the level of MAOB at nuclear accumbens without affecting the level of dopamine transporter. Daily injections of cocaine in rats caused behavioral sensitization. Withdrawal from cocaine in cocaine-sensitized rats induced an apparent time-dependent rebound of the MAOB protein level to about 200% over control on day 14 after withdrawal. Treatment of cocaine-withdrawn rats with the MAOB inhibitor deprenyl completely alleviated the behavioral sensitization to cocaine. Our results demonstrate a role of Sig-1R in transcriptional regulation and suggest cocaine may work through this newly discovered genomic action to achieve its addictive action. Results also suggest the MAOB inhibitor deprenyl as a therapeutic agent to block certain actions of cocaine during withdrawal. PMID:26554014

  13. Altered lymphatics in an ovine model of congenital heart disease with increased pulmonary blood flow.

    PubMed

    Datar, Sanjeev A; Johnson, Eric G; Oishi, Peter E; Johengen, Michael; Tang, Eric; Aramburo, Angela; Barton, Jubilee; Kuo, Hsuan-Chang; Bennett, Stephen; Xoinis, Konstantine; Reel, Bhupinder; Kalkan, Gokhan; Sajti, Eniko; Osorio, Oscar; Raff, Gary W; Matthay, Michael A; Fineman, Jeffrey R

    2012-03-15

    Abnormalities of the lymphatic circulation are well recognized in patients with congenital heart defects. However, it is not known how the associated abnormal blood flow patterns, such as increased pulmonary blood flow (PBF), might affect pulmonary lymphatic function and structure. Using well-established ovine models of acute and chronic increases in PBF, we cannulated the efferent lymphatic duct of the caudal mediastinal node and collected and analyzed lymph effluent from the lungs of lambs with acutely increased PBF (n = 6), chronically increased PBF (n = 6), and age-matched normal lambs (n = 8). When normalized to PBF, we found that lymph flow was unchanged following acute increases in PBF but decreased following chronic increases in PBF. The lymph:plasma protein ratio decreased with both acute and chronic increases in PBF. Lymph bioavailable nitric oxide increased following acute increases in PBF but decreased following chronic increases in PBF. In addition, we found perturbations in the transit kinetics of contrast material through the pleural lymphatics of lambs with chronic increases in PBF. Finally, there were structural changes in the pulmonary lymphatic system in lambs with chronic increases in PBF: lymphatics from these lambs were larger and more dilated, and there were alterations in the expression of vascular endothelial growth factor-C, lymphatic vessel endothelial hyaluronan receptor-1, and Angiopoietin-2, proteins known to be important for lymphatic growth, development, and remodeling. Taken together these data suggest that chronic increases in PBF lead to both functional and structural aberrations of lung lymphatics. These findings have important therapeutic implications that warrant further study.

  14. Repeated allergen exposure of sensitized Brown-Norway rats induces airway cell DNA synthesis and remodelling.

    PubMed

    Salmon, M; Walsh, D A; Koto, H; Barnes, P J; Chung, K F

    1999-09-01

    Chronic inflammation in asthmatic airways can lead to characteristic airway smooth muscle (ASM) thickening and pathological changes within the airway wall. This study assessed the effect of repeated allergen exposure on ASM and epithelial cell deoxyribonucleic acid (DNA) synthesis, cell recruitment and airway wall pathology. Brown-Norway rats were sensitized and then exposed to ovalbumin or saline aerosol every 3 days on six occasions. After the final exposure, rats were administered twice daily for 7 days with the DNA S-phase marker bromodeoxyuridine (BrdU). Using a triple immunohistochemical staining technique, BrdU incorporation into ASM and epithelium was quantified employing computer-assisted image analysis. There were >3-fold mean increases in BrdU incorporation into ASM from 1.3% of cells (95% confidence interval (CI) 1.0-1.6) in saline controls to 4.7% (95% CI 2.6-6.7) after allergen exposure (p<0.001), and in airway epithelium, from 1.3 (95% CI 0.6-2.0) BrdU-positive cells x mm basement membrane(-1) in saline controls to 4.9 (95% CI 3.0-6.7) after allergen exposure (p<0.001). There was increased subepithelial collagen deposition and mucus secretion along with a significant eosinophil and lymphocyte recruitment to the airways. Increased rates of deoxyribonucleic acid synthesis in both airway smooth muscle and epithelial cells along with changes to the airway wall pathology may precede the establishment of smooth muscle thickening and airway remodelling after repeated allergen exposure in rats. This model seems to be appropriate for studying structural changes within the airways as observed in asthma.

  15. Chronic administration of quercetin induces biomechanical and pharmacological remodeling in the rat coronary arteries.

    PubMed

    Monori-Kiss, A; Kiss, F; Restifo, J M; Monos, E; Nadasy, G L

    2017-09-22

    Acute dilation brought about by the dietary flavonoid quercetin in coronary arterioles has been described earlier, but no information is available on its chronic effects. Male Wistar rats (body weight about 190 g) were divided to two groups: the quercetin-treated group (n=22) had quercetin supplementation of approximately 30 mg/kg/day, whereas the control group (n=20) had none. After eight weeks of treatment, intramural coronary arterioles with identical passive diameters (178+/-14 microm and 171+/-9 microm) were prepared and their biomechanics and pharmacological reactivities were tested using pressure arteriography ex vivo. The spontaneous tone of quercetin-treated arteries was higher (16.5+/-1.9 % vs. 12.9+/-0.9 %), which resulted in a reduced lumen size (144+/-9 microm vs. 167+/-12 microm), thicker vascular wall (22.6+/-1.8 microm vs. 17.4+/-1.6 microm) and decreased tangential wall stress (16.8+/-1.1 kPa vs. 20.5+/-1.6 kPa) in supplemented animals (in spontaneous tone at 50 mm Hg, p<0.01 in all these comparisons). Elevated basal NO release resulted in increased endothelial dilation in quercetin-treated animals, especially at higher intraluminal pressures (10.8+/-2.5 % vs. 5.7+/-1.3 % at 70 mm Hg, p<0.01). We found remodeling of the geometry of coronary arterioles to ensure higher dilatory reserve and nitrogen monoxide production, as well as lowered elastic stress of the vessel wall.

  16. Use of a whole-slide imaging system to assess the presence and alteration of lymphatic vessels in joint sections of arthritic mice

    PubMed Central

    Shi, J; Liang, Q; Wang, Y; Mooney, RA; Boyce, BF; Xing, L

    2013-01-01

    We investigated the presence and alteration of lymphatic vessels in joints of arthritic mice using a whole-slide imaging system. Joints and long bone sections were cut from paraffin blocks of two mouse models of arthritis: meniscal-ligamentous injury (MLI)-induced osteoarthritis (OA) and TNF transgene (TNF-Tg)-induced rheumatoid arthritis (RA). MLI-OA mice were fed a high fat diet to accelerate OA development. TNF-Tg mice were treated with lymphatic growth factor VEGF-C virus to stimulate lymphangiogenesis. Sections were double immunofluorescence stained with anti-podoplanin and alpha-smooth muscle action. The area and number of lymphatic capillaries and mature lymphatic vessels were determined using a whole-slide imaging system and its associated software. Lymphatic vessels in joints were distributed in soft tissues mainly around the joint capsule, ligaments, fat pads and muscles. In long bones, enriched lymphatic vessels were present in the periosteal areas adjacent to the blood vessels. Occasionally, lymphatic vessels were observed in the cortical bone. Increased lymphatic capillaries, but decreased mature lymphatic vessels, were detected in both OA and RA joints. VEGF-C treatment increased lymphatic capillary and mature vessel formation in RA joints. We demonstrated decreased mature lymphatic vessels in the joints of mouse models of severe OA and RA. VEGF-C treatment increased the lymphatic vessel number and area in RA joints. Our findings suggest that the lymphatic system may play an important role in arthritis pathogenesis and treatment. PMID:23173750

  17. Differential expression of extracellular matrix remodeling genes in a murine model of bleomycin-induced pulmonary fibrosis.

    PubMed Central

    Swiderski, R. E.; Dencoff, J. E.; Floerchinger, C. S.; Shapiro, S. D.; Hunninghake, G. W.

    1998-01-01

    Exposure to the chemotherapeutic drug bleomycin leads to pulmonary fibrosis in humans and has been widely used in animal models of the disease. Using C57BL/6 bleomycin-sensitive mice, pulmonary fibrosis was induced by multiple intraperitoneal injections of the drug. An increase in the relative amounts of steady-state alpha1(I) procollagen, alpha1(III) procollagen, and fibronectin mRNA as well as histopathological evidence of fibrosis was observed. The effect of bleomycin on the expression of the enzymes responsible for extracellular matrix degradation, the matrix metalloproteinases (MMPs), and their inhibitors (TIMPs), was selective and showed temporal differences during the development of fibrosis. Of the MMPs tested, bleomycin treatment resulted in the up-regulation of gelatinase A and macrophage metalloelastase gene expression in whole-lung homogenates, whereas gelatinase B, stromelysin-1, and interstitial collagenase gene expression was not significantly changed. Timp2 and Timp3, the murine homologues of the respective TIMP genes, were constitutively expressed, whereas Timp1 was markedly up-regulated during fibrosis. The strong correlation between enhanced extracellular matrix gene expression, differential MMP and TIMP gene expression, and histopathological evidence of fibrosis suggest that dysregulated matrix remodeling is likely to contribute to the pathology of bleomycin-induced pulmonary fibrosis. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:9502424

  18. Adaptation of Candida albicans to environmental pH induces cell wall remodelling and enhances innate immune recognition

    PubMed Central

    Sorsby, Eleanor; Mahtey, Nabeel; Brown, Ian

    2017-01-01

    Candida albicans is able to proliferate in environments that vary dramatically in ambient pH, a trait required for colonising niches such as the stomach, vaginal mucosal and the GI tract. Here we show that growth in acidic environments involves cell wall remodelling which results in enhanced chitin and β-glucan exposure at the cell wall periphery. Unmasking of the underlying immuno-stimulatory β-glucan in acidic environments enhanced innate immune recognition of C. albicans by macrophages and neutrophils, and induced a stronger proinflammatory cytokine response, driven through the C-type lectin-like receptor, Dectin-1. This enhanced inflammatory response resulted in significant recruitment of neutrophils in an intraperitoneal model of infection, a hallmark of symptomatic vaginal colonisation. Enhanced chitin exposure resulted from reduced expression of the cell wall chitinase Cht2, via a Bcr1-Rim101 dependent signalling cascade, while increased β-glucan exposure was regulated via a non-canonical signalling pathway. We propose that this “unmasking” of the cell wall may induce non-protective hyper activation of the immune system during growth in acidic niches, and may attribute to symptomatic vaginal infection. PMID:28542528

  19. 18-HEPE, an n-3 fatty acid metabolite released by macrophages, prevents pressure overload-induced maladaptive cardiac remodeling.

    PubMed

    Endo, Jin; Sano, Motoaki; Isobe, Yosuke; Fukuda, Keiichi; Kang, Jing X; Arai, Hiroyuki; Arita, Makoto

    2014-07-28

    N-3 polyunsaturated fatty acids (PUFAs) have potential cardiovascular benefit, although the mechanisms underlying this effect remain poorly understood. Fat-1 transgenic mice expressing Caenorhabditis elegans n-3 fatty acid desaturase, which is capable of producing n-3 PUFAs from n-6 PUFAs, exhibited resistance to pressure overload-induced inflammation and fibrosis, as well as reduced cardiac function. Lipidomic analysis revealed selective enrichment of eicosapentaenoic acid (EPA) in fat-1 transgenic bone marrow (BM) cells and EPA-metabolite 18-hydroxyeicosapentaenoic acid (18-HEPE) in fat-1 transgenic macrophages. BM transplantation experiments revealed that fat-1 transgenic BM cells, but not fat-1 transgenic cardiac cells, contributed to the antiremodeling effect and that the 18-HEPE-rich milieu in the fat-1 transgenic heart was generated by BM-derived cells, most likely macrophages. 18-HEPE inhibited macrophage-mediated proinflammatory activation of cardiac fibroblasts in culture, and in vivo administration of 18-HEPE reproduced the fat-1 mice phenotype, including resistance to pressure overload-induced maladaptive cardiac remodeling. © 2014 Endo et al.

  20. 18-HEPE, an n-3 fatty acid metabolite released by macrophages, prevents pressure overload–induced maladaptive cardiac remodeling

    PubMed Central

    Endo, Jin; Sano, Motoaki; Isobe, Yosuke; Fukuda, Keiichi; Kang, Jing X.; Arai, Hiroyuki

    2014-01-01

    N-3 polyunsaturated fatty acids (PUFAs) have potential cardiovascular benefit, although the mechanisms underlying this effect remain poorly understood. Fat-1 transgenic mice expressing Caenorhabditis elegans n-3 fatty acid desaturase, which is capable of producing n-3 PUFAs from n-6 PUFAs, exhibited resistance to pressure overload–induced inflammation and fibrosis, as well as reduced cardiac function. Lipidomic analysis revealed selective enrichment of eicosapentaenoic acid (EPA) in fat-1 transgenic bone marrow (BM) cells and EPA-metabolite 18-hydroxyeicosapentaenoic acid (18-HEPE) in fat-1 transgenic macrophages. BM transplantation experiments revealed that fat-1 transgenic BM cells, but not fat-1 transgenic cardiac cells, contributed to the antiremodeling effect and that the 18-HEPE–rich milieu in the fat-1 transgenic heart was generated by BM-derived cells, most likely macrophages. 18-HEPE inhibited macrophage-mediated proinflammatory activation of cardiac fibroblasts in culture, and in vivo administration of 18-HEPE reproduced the fat-1 mice phenotype, including resistance to pressure overload–induced maladaptive cardiac remodeling. PMID:25049337

  1. The biological role of the unique molecule RCAS1: a bioactive marker that induces connective tissue remodeling and lymphocyte apoptosis.

    PubMed

    Sonoda, Kenzo; Miyamoto, Shingo; Nakashima, Manabu; Wake, Norio

    2008-01-01

    RCAS1 is a receptor-binding cancer antigen which is expressed on human uterine cervical adenocarcinoma cell line (SiSo). Finding a correlation between the expression of this gene and the overall survival of patients with 14 different types of cancer points to the clinical significance of this gene. Moreover, the expression RCAS1 correlates with other clinicopathological parameters including the histological type of cancer, its differentiation, tumor size, clinical stage, the depth of invasion, lymphovascular space involvement, lymph node metastasis, and positive peritoneal cytological results. RCAS1 can induce apoptosis in peripheral lymphocytes in vitro as well as in an increased number of apoptotic tumor-infiltrating lymphocytes. RCAS1 is also believed to contribute to the escape of tumor cells from immune surveillance. RCAS1 is secreted via ectodomain shedding, and its expression is related to changes in the characteristics of the extracellular matrix and to a reduced number of vimentin-positive tumor stromal cells, findings that suggest that RCAS1 may induce connective tissue remodeling. The concentration of RCAS1 in serum or pleural effusions has been found to be significantly higher in patients with several different types of cancer as compared to normal controls. Together, the available data shows that RCAS1 may have value as a biomarker for monitoring therapeutic efficacy. Further exploration of the biological function of RCAS1 should help in the development of new therapeutic strategies against human malignancies.

  2. Restoration of lymphatic function rescues obesity in Prox1-haploinsufficient mice

    PubMed Central

    Proulx, Steven T.; Dillard, Miriam E.; Johnson, Nicole; Detmar, Michael

    2016-01-01

    Prox1 heterozygous mice have a defective lymphatic vasculature and develop late-onset obesity. Chyle abnormally leaks from those vessels, accumulates in the surrounding tissues, and causes an increase in adipose tissue. We characterized the lymphatics of Prox1+/– mice to determine whether the extent of obesity correlated with the severity of lymphatic defects. The lymphatic vasculature in Prox1+/– mice exhibited reduced tracer clearance from the ear skin, dysfunctional perfusion of the lower legs, and reduced tracer uptake into the deep lymphatic collectors during mechanostimulation prior to the onset of obesity. Ear lymphatic vessels and leg collectors in Prox1+/– mice were disorganized and irregular, further confirming that defective lymphatic vessels are associated with obesity in Prox1+/– mice. We now provide conclusive in vivo evidence that demonstrates that leaky lymphatics mediate obesity in Prox1+/– mice, as restoration of lymphatic vasculature function was sufficient to rescue the obesity features in Prox1+/– mice. Finally, depth-lipomic profiling of lymph contents showed that free fatty acids induce adipogenesis in vitro. PMID:26973883

  3. New model of macrophage acquisition of the lymphatic endothelial phenotype.

    PubMed

    Hall, Kelly L; Volk-Draper, Lisa D; Flister, Michael J; Ran, Sophia

    2012-01-01

    Macrophage-derived lymphatic endothelial cell progenitors (M-LECPs) contribute to new lymphatic vessel formation, but the mechanisms regulating their differentiation, recruitment, and function are poorly understood. Detailed characterization of M-LECPs is limited by low frequency in vivo and lack of model systems allowing in-depth molecular analyses in vitro. Our goal was to establish a cell culture model to characterize inflammation-induced macrophage-to-LECP differentiation under controlled conditions. Time-course analysis of diaphragms from lipopolysaccharide (LPS)-treated mice revealed rapid mobilization of bone marrow-derived and peritoneal macrophages to the proximity of lymphatic vessels followed by widespread (∼50%) incorporation of M-LECPs into the inflamed lymphatic vasculature. A differentiation shift toward the lymphatic phenotype was found in three LPS-induced subsets of activated macrophages that were positive for VEGFR-3 and many other lymphatic-specific markers. VEGFR-3 was strongly elevated in the early stage of macrophage transition to LECPs but undetectable in M-LECPs prior to vascular integration. Similar transient pattern of VEGFR-3 expression was found in RAW264.7 macrophages activated by LPS in vitro. Activated RAW264.7 cells co-expressed VEGF-C that induced an autocrine signaling loop as indicated by VEGFR-3 phosphorylation inhibited by a soluble receptor. LPS-activated RAW264.7 macrophages also showed a 68% overlap with endogenous CD11b(+)/VEGFR-3(+) LECPs in the expression of lymphatic-specific genes. Moreover, when injected into LPS- but not saline-treated mice, GFP-tagged RAW264.7 cells massively infiltrated the inflamed diaphragm followed by integration into 18% of lymphatic vessels. We present a new model for macrophage-LECP differentiation based on LPS activation of cultured RAW264.7 cells. This system designated here as the "RAW model" mimics fundamental features of endogenous M-LECPs. Unlike native LECPs, this model is

  4. General surgery, translational lymphology and lymphatic surgery.

    PubMed

    Campisi, C; Witte, M H; Fulcheri, E; Campisi, C; Bellini, C; Villa, G; Campisi, C; Santi, P L; Parodi, A; Murdaca, G; Puppo, F; Boccardo, F

    2011-12-01

    A wide clinical experience in General Surgery has brought about a remarkable knowledge about lymphatic disorders both primary and secondary ones. Diagnostic and histopathological studies of lymphatic diseases allowed to better understand etiological aspects and pathophysiological mechanisms responsible of complex clinical features correlated to lymphatic dysfunctions. Translational lymphologic basic and clinical researches permitted to improve therapeutical approaches both from the medical and surgical point of view. Thus, strategies of treatment were proposed to prevent lymphatic injuries, to avoid lymphatic complications and to treat lymphatic diseases early in order to be able even to cure these pathologies.

  5. Dilated Thin-Walled Blood and Lymphatic Vessels in Human Endometrium: A Potential Role for VEGF-D in Progestin-Induced Break-Through Bleeding

    PubMed Central

    Donoghue, Jacqueline F.; McGavigan, C. Jay; Lederman, Fiona L.; Cann, Leonie M.; Fu, Lulu; Dimitriadis, Eva; Girling, Jane E.; Rogers, Peter A. W.

    2012-01-01

    Progestins provide safe, effective and cheap options for contraception as well as the treatment of a variety of gynaecological disorders. Episodes of irregular endometrial bleeding or breakthrough bleeding (BTB) are a major unwanted side effect of progestin treatment, such that BTB is the leading cause for discontinued use of an otherwise effective and popular medication. The cellular mechanisms leading to BTB are poorly understood. In this study, we make the novel finding that the large, dilated, thin walled vessels characteristic of human progestin-treated endometrium include both blood and lymphatic vessels. Increased blood and lymphatic vessel diameter are features of VEGF-D action in other tissues and we show by immunolocalisation and Western blotting that stromal cell decidualisation results in a significant increase in VEGF-D protein production, particularly of the proteolytically processed 21 kD form. Using a NOD/scid mouse model with xenografted human endometrium we were able to show that progestin treatment causes decidualisation, VEGF-D production and endometrial vessel dilation. Our results lead to a novel hypothesis to explain BTB, with stromal cell decidualisation rather than progestin treatment per se being the proposed causative event, and VEGF-D being the proposed effector agent. PMID:22383980

  6. Bone morphogenic protein-2 regulates the myogenic differentiation of PMVECs in CBDL rat serum-induced pulmonary microvascular remodeling.

    PubMed

    Liu, Chang; Chen, Lin; Zeng, Jing; Cui, Jian; Ning, Jiao-Nin; Wang, Guan-Song; Belguise, Karine; Wang, Xiaobo; Qian, Gui-Sheng; Lu, Kai-Zhi; Yi, Bin

    2015-08-01

    Hepatopulmonary syndrome (HPS) is characterized by an arterial oxygenation defect induced by intrapulmonary vasodilation (IPVD) that increases morbidity and mortality. In our previous study, it was determined that both the proliferation and the myogenic differentiation of pulmonary microvascular endothelial cells (PMVECs) play a key role in the development of IPVD. However, the molecular mechanism underlying the relationship between IPVD and the myogenic differentiation of PMVECs remains unknown. Additionally, it has been shown that bone morphogenic protein-2 (BMP2), via the control of protein expression, may regulate cell differentiation including cardiomyocyte differentiation, neuronal differentiation and odontoblastic differentiation. In this study, we observed that common bile duct ligation (CBDL)-rat serum induced the upregulation of the expression of several myogenic proteins (SM-α-actin, calponin, SM-MHC) and enhanced the expression levels of BMP2 mRNA and protein in PMVECs. We also observed that both the expression levels of Smad1/5 and the activation of phosphorylated Smad1/5 were significantly elevated in PMVECs following exposure to CBDL-rat serum, which was accompanied by the down-regulation of Smurf1. The blockage of the BMP2/Smad signaling pathway with Noggin inhibited the myogenic differentiation of PMVECs, a process that was associated with relatively low expression levels of both SM-α-actin and calponin in the setting of CBDL-rat serum exposure, although SM-MHC expression was not affected. These findings suggested that the BMP2/Smad signaling pathway is involved in the myogenic differentiation of the PMVECs. In conclusion, our data highlight the pivotal role of BMP2 in the CBDL-rat serum-induced myogenic differentiation of PMVECs via the activation of both Smad1 and Smad5 and the down-regulation of Smurf1, which may represent a potential therapy for HPS-induced pulmonary vascular remodeling.

  7. Combination Treatment With Antihypertensive Agents Enhances the Effect of Qiliqiangxin on Chronic Pressure Overload-induced Cardiac Hypertrophy and Remodeling in Male Mice.

    PubMed

    Ye, Yong; Gong, Hui; Wang, Xingxu; Wu, Jian; Wang, Shijun; Yuan, Jie; Yin, Peipei; Jiang, Guoliang; Li, Yang; Ding, Zhiwen; Zhang, Weijing; Zhou, Jingmin; Ge, Junbo; Zou, Yunzeng

    2015-06-01

    We previously showed that Qiliqiangxin (QL) capsules could ameliorate cardiac hypertrophy and remodeling in a mouse model of pressure overload. Here, we compared the effects of QL alone with those of QL combined with the following 3 types of antihypertensive drugs on cardiac remodeling and dysfunction induced by pressure overload for 4 weeks in mice: an angiotensin II type 1 receptor (AT1-R) blocker (ARB), an angiotensin-converting enzyme inhibitor (ACEI), and a β-adrenergic receptor (β-AR) blocker (BB). Adult male mice (C57B/L6) were subjected to either transverse aortic constriction or sham operation for 4 weeks, and the drugs (or saline) were orally administered through gastric tubes. Cardiac function and remodeling were evaluated through echocardiography, catheterization, histology, and analysis of hypertrophic gene expression. Cardiomyocyte apoptosis and autophagy, AT1-R and β1-AR expression, and cell proliferation-related molecules were also examined. Although pressure overload-induced cardiac remodeling and dysfunction, hypertrophic gene reprogramming, AT1-R and β1-AR expression, and ERK phosphorylation were significantly attenuated by QL alone, QL + ARB, QL + ACEI, and QL + BB, the attenuation was stronger in the combination treatment groups. Moreover, apoptosis was reduced to a larger extent by each combination treatment than by QL alone, whereas autophagy was more strongly attenuated by either QL + ARB or QL + ACEI. None of the treatments significantly upregulated ErbB2 or ErbB4 phosphorylation, and none significantly downregulated C/EBPβ expression. Therefore, the effects of QL on chronic pressure overload-induced cardiac remodeling may be significantly increased when QL is combined with an ARB, an ACEI, or a BB.

  8. The effect of CCL3 and CCR1 in bone remodeling induced by mechanical loading during orthodontic tooth movement in mice.

    PubMed

    Taddei, Silvana R de Albuquerque; Queiroz-Junior, Celso M; Moura, Adriana P; Andrade, Ildeu; Garlet, Gustavo P; Proudfoot, Amanda E I; Teixeira, Mauro M; da Silva, Tarcília A

    2013-01-01

    Bone remodeling is affected by mechanical loading and inflammatory mediators, including chemokines. The chemokine (C-C motif) ligand 3 (CCL3) is involved in bone remodeling by binding to C-C chemokine receptors 1 and 5 (CCR1 and CCR5) expressed on osteoclasts and osteoblasts. Our group has previously demonstrated that CCR5 down-regulates mechanical loading-induced bone resorption. Thus, the present study aimed to investigate the role of CCR1 and CCL3 in bone remodeling induced by mechanical loading during orthodontic tooth movement in mice. Our results showed that bone remodeling was significantly decreased in CCL3(-/-) and CCR1(-/-) mice and in animals treated with Met-RANTES (an antagonist of CCR5 and CCR1). mRNA levels of receptor activator of nuclear factor kappa-B (RANK), its ligand RANKL, tumor necrosis factor alpha (TNF-α) and RANKL/osteoprotegerin (OPG) ratio were diminished in the periodontium of CCL3(-/-) mice and in the group treated with Met-RANTES. Met-RANTES treatment also reduced the levels of cathepsin K and metalloproteinase 13 (MMP13). The expression of the osteoblast markers runt-related transcription factor 2 (RUNX2) and periostin was decreased, while osteocalcin (OCN) was augmented in CCL3(-/-) and Met-RANTES-treated mice. Altogether, these findings show that CCR1 is pivotal for bone remodeling induced by mechanical loading during orthodontic tooth movement and these actions depend, at least in part, on CCL3. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. IL-17A induces chromatin remodeling promoting IL-8 release in bronchial epithelial cells: Effect of Tiotropium.

    PubMed

    Anzalone, Giulia; Gagliardo, Rosalia; Bucchieri, Fabio; Albano, Giusy Daniela; Siena, Liboria; Montalbano, Angela Marina; Bonanno, Anna; Riccobono, Loredana; Pieper, Michael Paul; Gjomarkaj, Mark; Profita, Mirella

    2016-05-01

    IL-17A plays a key role in the persistence of airway inflammation, oxidative stress, and reduction of steroid-sensitivity in COPD. We studied the effect of IL-17A on chromatin remodeling and IL-8 production. We measured the levels of IL-8 and IL-17A in induced sputum supernatants (ISS) from healthy controls (HCs), healthy smokers (HSs), and COPD patients by enzyme-linked immunosorbent assay (ELISA). A human bronchial epithelial cell line (16HBE) was stimulated with ISS from HCs, HSs, or COPD subjects. IL-8 was evaluated in 16HBE by Western blot and real-time polymerase chain reaction (PCR). Histone deacetylase 2 (HDAC2), acetyl histone H3 (Ac-His H3) (k9) and inhibitor kappa kinase alpha (IKKα) levels were evaluated in the nuclear extract by Western blot. Finally, we evaluated the effect of IL-17A depletion in ISS, the silencing of IKKα, and the anti-inflammatory effects of Tiotropium Spiriva® (100nM) on 16HBE. IL-8 and IL-17A levels were higher in ISS from COPD patients and HSs than from HCs. IL-8 protein and messenger RNA (mRNA) levels were increased in 16HBE stimulated with ISS from COPD patients compared with untreated cells. Furthermore, ISS from COPD patients reduced the nuclear levels of HDAC2 while increasing the activity of both Ac-His H3 (k9) and IKKα in stimulated 16HBE. IL-17A depletion in ISS and the IKKα silencing in 16HBE significantly increased the nuclear levels of HDAC2, reduced Ac-His H3 (k9), and promoted IL-8 synthesis in stimulated 16HBE. Tiotropium controls the proinflammatory activity generated by ISS from COPD patients in 16HBE. IL-17A present in the airway of COPD patients, which induces chromatin remodeling, promotes the release of IL-8 in the bronchial epithelium. Tiotropium is able to control this proinflammatory activity. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Substrate stiffness influences TGF-β1-induced differentiation of bronchial fibroblasts into myofibroblasts in airway remodeling.

    PubMed

    Shi, Yanling; Dong, Yuhui; Duan, Yiyuan; Jiang, Xuemei; Chen, Cheng; Deng, Linhong

    2013-02-01

    Chronic inflammation and remodeling of the bronchial wall are basic hallmarks of asthma. During the process of bronchial wall remodeling, inflammatory factors, such as transforming growth factor-β1 (TGF-β1), are known to induce the differentiation of fibroblasts into myofibroblasts, which leads to excessive synthesis and secretion of extracellular matrix (ECM) proteins, thus thickening and stiffening the basement membrane. However, it has not been thoroughly studied whether or not substrate stiffening affects the TGF-β1‑induced myofibroblast differentiation. In the present study, the influence of substrate stiffness on the process of bronchial fibroblast differentiation into myofibroblasts in the presence of TGF-β1 was investigated. To address this question, we synthesized polydimethylsiloxane (PDMS) substrates with varying degrees of stiffness (Young's modulus of 1, 10 and 50 kPa, respectively). We cultured bronchial fibroblasts on the substrates of varying stiffness in media containing TGF-β1 (10 ng/ml) to stimulate the differentiation of fibroblasts into myofibroblasts. Myofibroblast differentiation was examined using semi-quantitative RT-PCR for the expression of α-smooth muscle actin (α-SMA) mRNA and collagen I mRNA, the enzyme-linked immunosorbent assay method was used to assess the expression of collagen I protein and western blotting to assess the expression of α-SMA protein. The optical magnetic twisting cytometry (OMTC) method was used for the changing of cell mechanical properties. Our findings suggest that when fibroblasts were incubated with TGF-β1 (10 ng/ml) on substrate of varying stiffness, the differentiation of fibroblasts into myofibroblasts was enhanced by increasing substrate stiffness. Compared with those cultured on substrate with Young's modulus of 1 kPa, the mRNA and protein expression of collagen I and α-SMA of fibroblasts cultured on substrates with Young's modulus of 10 and 50 kPa were increased. Furthermore, with the

  11. Alcohol-induced electrical remodeling: effects of sustained short-term ethanol infusion on ion currents in rabbit atrium.

    PubMed

    Laszlo, Roman; Eick, Christian; Schwiebert, Mareike; Schreiner, Birgit; Weig, Hans-Joerg; Weretka, Slawomir; Bosch, Ralph F; Schreieck, Juergen

    2009-10-01

    In some patients, above-average alcohol consumption before occurrence of atrial fibrillation (AF) in terms of a "holiday heart syndrome" (HHS) can be determined. There is evidence that long before development of apparent alcohol-induced cardiomyopathy, above-average alcohol consumption generates an arrhythmogenic substrate which abets the onset of AF. Changes of atrial current densities in terms of an electrical remodeling after sustained short-term ethanol infusion in rabbits as a potential part of HHS pathophysiology were examined in this study. Rabbits of the ethanol group (EG) received sustained short-term intravenous alcohol infusion for 120 hours (during infusion period, blood alcohol level did not fall below 158 mg/dl), whereas NaCl 0.9% was infused in the placebo group (PG). Using patch clamp technique in whole-cell mode, atrial current densities were measured and compared between both groups. Ethanol infusion did not alter current densities of I(to) [58.7 +/- 5.0 pA/pF (PG, n = 20 cells) vs. 53.9 +/- 5.0 pA/pF (EG, n = 24)], I(sus) [11.3 +/- 1.4 pA/pF (PG, n = 20) vs. 10.2 +/- 1.0 pA/pF (EG, n = 24)], and I(K1) [-1.6 +/- 0.3 pA/pF (PG, n = 17) vs. -2.0 +/- 0.3 pA/pF (EG, n = 22)]. However, alcohol infusion resulted in a remarkable reduction of I(Ca,L) current densities [-28.4 +/- 1.8 pA/pF (PG, n = 20) vs. -15.2 +/- 1.4 pA/pF (EG, n = 22)] and I(Na) [-75.4 +/- 3.6 pA/pF (PG, n = 17) vs. -35.4 +/- 4.4 pA/pF (EG, n = 21)], respectively. Sustained short-term ethanol infusion in rabbits alters atrial current densities. HHS might be favored by alcohol-induced atrial electrical remodeling.

  12. Structural and biochemical remodelling in catecholamine-induced cardiomyopathy: comparative and ontogenetic aspects.

    PubMed

    Ostádal, B; Pelouch, V; Ostádalová, I; Nováková, O

    Excessive release or administration of beta-mimetic catecholamines may induce cardiomegaly, necrotic lesions and accumulation of connective tissue in the heart of adult homoiotherms. It was examined here whether similar changes can also be observed at different stages of evolution of the cardiovascular system, i.e. in poikilotherms and in homoiotherms during embryonic life. Sensitivity of the poikilothermic hearts (carp, frog, turtle) to isoproterenol (IPRO) was significantly lower than in the homoiotherms. Necrotic lesions, if present, were localized in the inner spongious musculature which has no vascular supply but which exhibits higher activities of enzymes connected with aerobic oxidation. Moreover, the IPRO-induced decrease of the phospholipid content was also significantly more expressed in the spongious layer. IPRO treatment did not influence the total weight of the fish heart but the proportion of the outer compact layer was significantly higher. These changes were accompanied by an increase of collagen, higher water content and an increase of isomyosin with a lower ATPase activity. The response of the poikilothermic heart to IPRO-induced overload thus differs significantly from that in the homoiotherms. The administration of IPRO during embryonic life of homoiotherms (chick) induces serious cardiovascular disturbances, including cardiomegaly and cellular oedema. Necroses of myofibrils, characteristic of IPRO-induced lesions of adults, were, however, rather exceptional. IPRO did not elevate the concentration of 85Sr (as a calcium homologue) in the immature myocardium; it seems, therefore, that IPRO-induced changes of the embryonic heart are not necessarily due to an intracellular calcium overload. It may be concluded that the character of catecholamine-induced cardiomyopathy is not uniform and depends strictly on the stage of cardiac development.

  13. Lymphatic regulation in nonmammalian vertebrates.

    PubMed

    Hedrick, Michael S; Hillman, Stanley S; Drewes, Robert C; Withers, Philip C

    2013-08-01

    All vertebrate animals share in common the production of lymph through net capillary filtration from their closed circulatory system into their tissues. The balance of forces responsible for net capillary filtration and lymph formation is described by the Starling equation, but additional factors such as vascular and interstitial compliance, which vary markedly among vertebrates, also have a significant impact on rates of lymph formation. Why vertebrates show extreme variability in rates of lymph formation and how nonmammalian vertebrates maintain plasma volume homeostasis is unclear. This gap hampers our understanding of the evolution of the lymphatic system and its interaction with the cardiovascular system. The evolutionary origin of the vertebrate lymphatic system is not clear, but recent advances suggest common developmental factors for lymphangiogenesis in teleost fishes, amphibians, and mammals with some significant changes in the water-land transition. The lymphatic system of anuran amphibians is characterized by large lymphatic sacs and two pairs of lymph hearts that return lymph into the venous circulation but no lymph vessels per se. The lymphatic systems of reptiles and some birds have lymph hearts, and both groups have extensive lymph vessels, but their functional role in both lymph movement and plasma volume homeostasis is almost completely unknown. The purpose of this review is to present an evolutionary perspective in how different vertebrates have solved the common problem of the inevitable formation of lymph from their closed circulatory systems and to point out the many gaps in our knowledge of this evolutionary progression.

  14. Connective tissue growth factor inhibition attenuates left ventricular remodeling and dysfunction in pressure overload-induced heart failure.

    PubMed

    Szabó, Zoltán; Magga, Johanna; Alakoski, Tarja; Ulvila, Johanna; Piuhola, Jarkko; Vainio, Laura; Kivirikko, Kari I; Vuolteenaho, Olli; Ruskoaho, Heikki; Lipson, Kenneth E; Signore, Pierre; Kerkelä, Risto

    2014-06-01

    Connective tissue growth factor (CTGF) is involved in the pathogenesis of various fibrotic disorders. However, its role in the heart is not clear. To investigate the role of CTGF in regulating the development of cardiac fibrosis and heart failure, we subjected mice to thoracic aortic constriction (TAC) or angiotensin II infusion, and antagonized the function of CTGF with CTGF monoclonal antibody (mAb). After 8 weeks of TAC, mice treated with CTGF mAb had significantly better preserved left ventricular (LV) systolic function and reduced LV dilatation compared with mice treated with control immunoglobulin G. CTGF mAb-treated mice exhibited significantly smaller cardiomyocyte cross-sectional area and reduced expression of hypertrophic marker genes. CTGF mAb treatment reduced the TAC-induced production of collagen 1 but did not significantly attenuate TAC-induced accumulation of interstitial fibrosis. Analysis of genes regulating extracellular matrix proteolysis showed decreased expression of plasminogen activator inhibitor-1 and matrix metalloproteinase-2 in mice treated with CTGF mAb. In contrast to TAC, antagonizing the function of CTGF had no effect on LV dysfunction or LV hypertrophy in mice subjected to 4-week angiotensin II infusion. Further analysis showed that angiotensin II-induced expression of hypertrophic marker genes or collagens was not affected by treatment with CTGF mAb. In conclusion, CTGF mAb protects from adverse LV remodeling and LV dysfunction in hearts subjected to pressure overload by TAC. Antagonizing the function of CTGF may offer protection from cardiac end-organ damage in patients with hypertension.

  15. Retinal remodeling.

    PubMed

    Jones, B W; Kondo, M; Terasaki, H; Lin, Y; McCall, M; Marc, R E

    2012-07-01

    Retinal photoreceptor degeneration takes many forms. Mutations in rhodopsin genes or disorders of the retinal pigment epithelium, defects in the adenosine triphosphate binding cassette transporter, ABCR gene defects, receptor tyrosine kinase defects, ciliopathies and transport defects, defects in both transducin and arrestin, defects in rod cyclic guanosine 3',5'-monophosphate phosphodiesterase, peripherin defects, defects in metabotropic glutamate receptors, synthetic enzymatic defects, defects in genes associated with signaling, and many more can all result in retinal degenerative disease like retinitis pigmentosa (RP) or RP-like disorders. Age-related macular degeneration (AMD) and AMD-like disorders are possibly due to a constellation of potential gene targets and gene/gene interactions, while other defects result in diabetic retinopathy or glaucoma. However, all of these insults as well as traumatic insults to the retina result in retinal remodeling. Retinal remodeling is a universal finding subsequent to retinal degenerative disease that results in deafferentation of the neural retina from photoreceptor input as downstream neuronal elements respond to loss of input with negative plasticity. This negative plasticity is not passive in the face of photoreceptor degeneration, with a phased revision of retinal structure and function found at the molecular, synaptic, cell, and tissue levels involving all cell classes in the retina, including neurons and glia. Retinal remodeling has direct implications for the rescue of vision loss through bionic or biological approaches, as circuit revision in the retina corrupts any potential surrogate photoreceptor input to a remnant neural retina. However, there are a number of potential opportunities for intervention that are revealed through the study of retinal remodeling, including therapies that are designed to slow down photoreceptor loss, interventions that are designed to limit or arrest remodeling events, and

  16. Adiponectin Attenuates Angiotensin II-Induced Vascular Smooth Muscle Cell Remodeling through Nitric Oxide and the RhoA/ROCK Pathway

    PubMed Central

    Nour-Eldine, Wared; Ghantous, Crystal M.; Zibara, Kazem; Dib, Leila; Issaa, Hawraa; Itani, Hana A.; El-Zein, Nabil; Zeidan, Asad

    2016-01-01

    Introduction: Adiponectin (APN), an adipocytokine, exerts protective effects on cardiac remodeling, while angiotensin II (Ang II) induces hypertension and vascular remodeling. The potential protective role of APN on the vasculature during hypertension has not been fully elucidated yet. Here, we evaluate the molecular mechanisms of the protective role of APN in the physiological response of the vascular wall to Ang II. Methods and Results: Rat aortic tissues were used to investigate the effect of APN on Ang II-induced vascular remodeling and hypertrophy. We investigated whether nitric oxide (NO), the RhoA/ROCK pathway, actin cytoskeleton remodeling, and reactive oxygen species (ROS) mediate the anti-hypertrophic effect of APN. Ang II-induced protein synthesis was attenuated by pre-treatment with APN, NO donor S-nitroso-N-acetylpenicillamine (SNAP), or cGMP. The hypertrophic response to Ang II was associated with a significant increase in RhoA activation and vascular force production, which were prevented by APN and SNAP. NO was also associated with inhibition of Ang II-induced phosphorylation of cofilin. In addition, immunohistochemistry revealed that 24 h Ang II treatment increased the F- to G-actin ratio, an effect that was inhibited by SNAP. Ang II-induced ROS formation and upregulation of p22phox mRNA expression were inhibited by APN and NO. Both compounds failed to inhibit Nox1 and p47phox expression. Conclusion: Our results suggest that the anti-hypertrophic effects of APN are due, in part, to NO-dependent inhibition of the RhoA/ROCK pathway and ROS formation. PMID:27092079

  17. Diet-induced Obesity Alters Bone Remodeling Leading to Decreased Femoral Trabecular Bone Mass in Mice

    USDA-ARS?s Scientific Manuscript database

    Body mass derived from an obesity condition may be detrimental to bone health but the mechanism is unknown. This study was to examine changes in bone structure and serum cytokines related to bone metabolism in obese mice induced by a high-fat diet(HFD). Mice fed the HFD were obese and had higher ser...

  18. Fluid-solid modeling of lymphatic valves

    NASA Astrophysics Data System (ADS)

    Caulk, Alexander; Ballard, Matthew; Nepiyushchikh, Zhanna; Dixon, Brandon; Alexeev, Alexander

    2015-11-01

    The lymphatic system performs important physiological functions such as the return of interstitial fluid to the bloodstream to maintain tissue fluid balance, as well as the transport of immune cells in the body. It utilizes contractile lymphatic vessels, which contain valves that open and close to allow flow in only one direction, to directionally pump lymph against a pressure gradient. We develop a fluid-solid model of geometrically representative lymphatic valves. Our model uses a hybrid lattice-Boltzmann lattice spring method to capture fluid-solid interactions with two-way cou