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Sample records for impaired cellular responses

  1. Impaired cellular immune response to diphtheria and tetanus vaccines in children after thoracic transplantation.

    Science.gov (United States)

    Urschel, Simon; Rieck, Birgit D; Birnbaum, Julia; Dalla Pozza, Robert; Rieber, Nikolaus; Januszewska, Katarzyna; Fuchs, Alexandra; West, Lori J; Netz, Heinrich; Belohradsky, Bernd H

    2011-05-01

    Safety and immunogenicity of diphtheria and tetanus booster vaccination were evaluated in 28 children after thoracic transplantation. Adverse events were documented in a patient diary. Blood was collected prior to and four wk after vaccination. Specific antibody concentrations were measured by ELISA. Lymphocytes were investigated for expression of activation markers (CD25, HLA-DR) by flow cytometry and proliferation assays with and without stimulation. Post-vaccination antibody titers were higher than prevaccination (p antibody levels against diphtheria (p antibodies was negatively correlated with tacrolimus dose, and impaired cellular immunity was associated with higher tacrolimus dose and steroid use. Adverse events were similar to the general population; serious adverse events and rejection did not occur. Vaccination with inactivated vaccines can be performed safely in immunosuppressed children after thoracic transplantation and induces protective antibody levels in the majority of patients. Impaired induction of specific cellular immunity is correlated with intensity of immunosuppression and may explain reduced sustainability of antibodies.

  2. Microbial Degradation of Cellular Kinases Impairs Innate Immune Signaling and Paracrine TNFα Responses.

    Science.gov (United States)

    Barth, Kenneth; Genco, Caroline Attardo

    2016-10-04

    The NFκB and MAPK signaling pathways are critical components of innate immunity that orchestrate appropriate immune responses to control and eradicate pathogens. Their activation results in the induction of proinflammatory mediators, such as TNFα a potent bioactive molecule commonly secreted by recruited inflammatory cells, allowing for paracrine signaling at the site of an infection. In this study we identified a novel mechanism by which the opportunistic pathogen Porphyromonas gingivalis dampens innate immune responses by disruption of kinase signaling and degradation of inflammatory mediators. The intracellular immune kinases RIPK1, TAK1, and AKT were selectively degraded by the P. gingivalis lysine-specific gingipain (Kgp) in human endothelial cells, which correlated with dysregulated innate immune signaling. Kgp was also observed to attenuate endothelial responsiveness to TNFα, resulting in a reduction in signal flux through AKT, ERK and NFκB pathways, as well as a decrease in downstream proinflammatory mRNA induction of cytokines, chemokines and adhesion molecules. A deficiency in Kgp activity negated decreases to host cell kinase protein levels and responsiveness to TNFα. Given the essential role of kinase signaling in immune responses, these findings highlight a unique mechanism of pathogen-induced immune dysregulation through inhibition of cell activation, paracrine signaling, and dampened cellular proinflammatory responses.

  3. Impaired cellular immune response to tetanus toxoid but not to cytomegalovirus in effectively HAART-treated HIV-infected children.

    Science.gov (United States)

    Alsina, Laia; Noguera-Julian, Antoni; Fortuny, Clàudia

    2013-05-07

    Despite of highly active antiretroviral therapy, the response to vaccines in HIV-infected children is poor and short-lived, probably due to a defect in cellular immune responses. We compared the cellular immune response (assessed in terms of IFN-γ production) to tetanus toxoid and to cytomegalovirus in a series of 13 HIV-perinatally-infected children and adolescents with optimal immunovirological response to first line antiretroviral therapy, implemented during chronic infection. A stronger cellular response to cytomegalovirus (11 out of 13 patients) was observed, as compared to tetanus toxoid (1 out of 13; p=0.003). These results suggest that the repeated exposition to CMV, as opposed to the past exposition to TT, is able to maintain an effective antigen-specific immune response in stable HIV-infected pediatric patients and strengthen current recommendations on immunization practices in these children.

  4. Cellular immune responses to HIV

    Science.gov (United States)

    McMichael, Andrew J.; Rowland-Jones, Sarah L.

    2001-04-01

    The cellular immune response to the human immunodeficiency virus, mediated by T lymphocytes, seems strong but fails to control the infection completely. In most virus infections, T cells either eliminate the virus or suppress it indefinitely as a harmless, persisting infection. But the human immunodeficiency virus undermines this control by infecting key immune cells, thereby impairing the response of both the infected CD4+ T cells and the uninfected CD8+ T cells. The failure of the latter to function efficiently facilitates the escape of virus from immune control and the collapse of the whole immune system.

  5. Cellular Response to Irradiation

    Institute of Scientific and Technical Information of China (English)

    LIU Bo; YAN Shi-Wei

    2011-01-01

    To explore the nonlinear activities of the cellular signaling system composed of one transcriptional arm and one protein-interaction arm, we use an irradiation-response module to study the dynamics of stochastic interactions.It is shown that the oscillatory behavior could be described in a unified way when the radiation-derived signal and noise are incorporated.

  6. Low-level arsenic impairs glucose-stimulated insulin secretion in pancreatic beta cells: involvement of cellular adaptive response to oxidative stress.

    Science.gov (United States)

    Fu, Jingqi; Woods, Courtney G; Yehuda-Shnaidman, Einav; Zhang, Qiang; Wong, Victoria; Collins, Sheila; Sun, Guifan; Andersen, Melvin E; Pi, Jingbo

    2010-06-01

    Chronic exposure of humans to inorganic arsenic, a potent environmental oxidative stressor, is associated with incidence of type 2 diabetes (T2D). A key driver in the pathogenesis of T2D is impairment of pancreatic beta-cell function, with the hallmark of beta-cell function being glucose-stimulated insulin secretion (GSIS). Reactive oxygen species (ROS) derived from glucose metabolism serve as one of the metabolic signals for GSIS. Nuclear factor-erythroid 2-related factor 2 (Nrf2) is a central transcription factor regulating cellular adaptive response to oxidative stress. We tested the hypothesis that activation of Nrf2 and induction of antioxidant enzymes in response to arsenic exposure impedes glucose-triggered ROS signaling and thus GSIS. Exposure of INS-1(832/13) cells to low levels of arsenite led to decreased GSIS in a dose- and time-dependent fashion. Consistent with our hypothesis, a significantly enhanced Nrf2 activity, determined by its nuclear accumulation and induction of its target genes, was observed in arsenite-exposed cells. In keeping with the activation of Nrf2-mediated antioxidant response, intracellular glutathione and intracellular hydrogen peroxide-scavenging activity was dose dependently increased by arsenite exposure. Although the basal cellular peroxide level was significantly enhanced, the net percentage increase in glucose-stimulated intracellular peroxide production was markedly inhibited in arsenite-exposed cells. In contrast, insulin synthesis and the consensus GSIS pathway, including glucose transport and metabolism, were not significantly reduced by arsenite exposure. Our studies suggest that low levels of arsenic provoke a cellular adaptive oxidative stress response that increases antioxidant levels, dampens ROS signaling involved in GSIS, and thus disturbs beta-cell function.

  7. Complex cisplatin-double strand break (DSB) lesions directly impair cellular non-homologous end-joining (NHEJ) independent of downstream damage response (DDR) pathways.

    Science.gov (United States)

    Sears, Catherine R; Turchi, John J

    2012-07-13

    The treatment for advanced stage non-small cell lung cancer (NSCLC) often includes platinum-based chemotherapy and IR. Cisplatin and IR combination therapy display schedule and dose-dependent synergy, the mechanism of which is not completely understood. In a series of in vitro and cell culture assays in a NSCLC model, we investigated both the downstream and direct treatment and damage effects of cisplatin on NHEJ catalyzed repair of a DNA DSB. The results demonstrate that extracts prepared from cisplatin-treated cells are fully capable of NHEJ catalyzed repair of a DSB using a non-cisplatin-damaged DNA substrate in vitro. Similarly, using two different host cell reactivation assays, treatment of cells prior to transfection of a linear, undamaged reporter plasmid revealed no reduction in NHEJ compared with untreated cells. In contrast, transfection of a linear GFP-reporter plasmid containing site-specific, cisplatin lesions 6-bp from the termini revealed a significant impairment in DSB repair of the cisplatin-damaged DNA substrates in the absence of cellular treatment with cisplatin. Together, these data demonstrate that impaired NHEJ in combined cisplatin-IR treated cells is likely the result of a direct effect of cisplatin-DNA lesions near a DSB and that the indirect cellular effects of cisplatin treatment are not significant contributors to the synergistic cytotoxicity observed with combination cisplatin-IR treatment.

  8. The insect cellular immune response

    Institute of Scientific and Technical Information of China (English)

    Michael R. Strand

    2008-01-01

    The innate immune system of insects is divided into humoral defenses that include the production of soluble effector molecules and cellular defenses like phagocytosis and encapsulation that are mediated by hemocytes. This review summarizes current understanding of the cellular immune response. Insects produce several terminally differentiated types of hemocytes that are distinguished by morphology, molecular and antigenic markers, and function. The differentiated hemocytes that circulate in larval or nymphal stage insects arise from two sources: progenitor cells produced during embryogenesis and mesodermally derived hematopoietic organs. Regulation of hematopoiesis and hemocyte differentiation also involves several different signaling pathways. Phagocytosis and encapsulation require that hemocytes first recognize a given target as foreign followed by activation of downstream signaling and effector responses. A number of humoral and cellular receptors have been identified that recognize different microbes and multicellular parasites. In turn, activation of these receptors stimulates a number of signaling pathways that regulate different hemocyte functions. Recent studies also identify hemocytes as important sources of a number of humoral effector molecules required for killing different foreign invaders.

  9. Immune cellular response to HPV: current concepts

    Directory of Open Access Journals (Sweden)

    Maria Alice Guimarães Gonçalves

    Full Text Available Although cellular immunity is essential for the elimination of human papillomavirus (HPV, the mechanisms involved are still poorly understood. We summarize the main mechanisms involved in cellular immune response to infections caused by HPV. Immunotherapies for HPV-related cancers require the disruption of T-cell response control mechanisms, associated with the stimulation of the Th1 cytokine response.

  10. Cellular responses to environmental DNA damage

    Energy Technology Data Exchange (ETDEWEB)

    1994-08-01

    This volume contains the proceedings of the conference entitled Cellular Responses to Environmental DNA Damage held in Banff,Alberta December 1--6, 1991. The conference addresses various aspects of DNA repair in sessions titled DNA repair; Basic Mechanisms; Lesions; Systems; Inducible Responses; Mutagenesis; Human Population Response Heterogeneity; Intragenomic DNA Repair Heterogeneity; DNA Repair Gene Cloning; Aging; Human Genetic Disease; and Carcinogenesis. Individual papers are represented as abstracts of about one page in length.

  11. Characterizing heterogeneous cellular responses to perturbations.

    Science.gov (United States)

    Slack, Michael D; Martinez, Elisabeth D; Wu, Lani F; Altschuler, Steven J

    2008-12-01

    Cellular populations have been widely observed to respond heterogeneously to perturbation. However, interpreting the observed heterogeneity is an extremely challenging problem because of the complexity of possible cellular phenotypes, the large dimension of potential perturbations, and the lack of methods for separating meaningful biological information from noise. Here, we develop an image-based approach to characterize cellular phenotypes based on patterns of signaling marker colocalization. Heterogeneous cellular populations are characterized as mixtures of phenotypically distinct subpopulations, and responses to perturbations are summarized succinctly as probabilistic redistributions of these mixtures. We apply our method to characterize the heterogeneous responses of cancer cells to a panel of drugs. We find that cells treated with drugs of (dis-)similar mechanism exhibit (dis-)similar patterns of heterogeneity. Despite the observed phenotypic diversity of cells observed within our data, low-complexity models of heterogeneity were sufficient to distinguish most classes of drug mechanism. Our approach offers a computational framework for assessing the complexity of cellular heterogeneity, investigating the degree to which perturbations induce redistributions of a limited, but nontrivial, repertoire of underlying states and revealing functional significance contained within distinct patterns of heterogeneous responses.

  12. Dynamics of active cellular response under stress

    Science.gov (United States)

    de, Rumi; Zemel, Assaf; Safran, Samuel

    2008-03-01

    Forces exerted by and on adherent cells are important for many physiological processes such as wound healing and tissue formation. In addition, recent experiments have shown that stem cell differentiation is controlled, at least in part, by the elasticity of the surrounding matrix. Using a simple theoretical model that includes the forces due to both the mechanosensitive nature of cells and the elastic response of the matrix, we predict the dynamics of orientation of cells. The model predicts many features observed in measurements of cellular forces and orientation including the increase with time of the forces generated by cells in the absence of applied stress and the consequent decrease of the force in the presence of quasi-static stresses. We also explain the puzzling observation of parallel alignment of cells for static and quasi-static stresses and of nearly perpendicular alignment for dynamically varying stresses. In addition, we predict the response of the cellular orientation to a sinusoidally varying applied stress as a function of frequency. The dependence of the cell orientation angle on the Poisson ratio of the surrounding material can be used to distinguish systems in which cell activity is controlled by stress from those where cell activity is controlled by strain. Reference: Nature Physics, vol. 3, pp 655 (2007).

  13. Complex cellular responses to reactive oxygen species.

    Science.gov (United States)

    Temple, Mark D; Perrone, Gabriel G; Dawes, Ian W

    2005-06-01

    Genome-wide analyses of yeast provide insight into cellular responses to reactive oxygen species (ROS). Many deletion mutants are sensitive to at least one ROS, but no one oxidant is representative of 'oxidative stress' despite the widespread use of a single compound such as H(2)O(2). This has major implications for studies of pathological situations. Cells have a range of mechanisms for maintaining resistance that involves either induction or repression of many genes and extensive remodeling of the transcriptome. Cells have constitutive defense systems that are largely unique to each oxidant, but overlapping, inducible repair systems. The pattern of the transcriptional response to a particular ROS depends on its concentration, and 'classical' antioxidant systems that are induced by high concentrations of ROS can be repressed when cells adapt to low concentrations of ROS.

  14. Cellular immune responses towards regulatory cells.

    Science.gov (United States)

    Larsen, Stine Kiær

    2016-01-01

    This thesis describes the results from two published papers identifying spontaneous cellular immune responses against the transcription factors Foxp3 and Foxo3. The tumor microenvironment is infiltrated by cells that hinder effective tumor immunity from developing. Two of these cell types, which have been linked to a bad prognosis for patients, are regulatory T cells (Treg) and tolerogenic dendritic cells (DC). Tregs inhibit effector T cells from attacking the tumor through various mechanisms, including secreted factors and cell-to-cell contact. Tregs express the transcription factor Foxp3, which is necessary for their development and suppressive activities. Tolerogenic DCs participate in creating an environment in the tumor where effector T cells become tolerant towards the tumor instead of attacking it. The transcription factor Foxo3 was recently described to be highly expressed by tolerogenic DCs and to programme their tolerogenic influence. This thesis describes for the first time the existence of spontaneous cellular immune responses against peptides derived from Foxp3 and Foxo3. We have detected the presence of cytotoxic T cells that recognise these peptides in an HLA-A2 restricted manner in cancer patients and for Foxp3 in healthy donors as well. In addition, we have demonstrated that the Foxp3- and Foxo3-specific CTLs recognize Foxp3- and Foxo3-expressing cancer cell lines and importantly, suppressive immune cells, namely Tregs and in vitro generated DCs. Cancer immunotherapy is recently emerging as an important treatment modality improving the survival of selected patients. The current progress is largely owing to targeting of the immune suppressive milieu that is dominating the tumor microenvironment. This is being done through immune checkpoint blockade with CTLA-4 and PD-1/PD-L1 antibodies and through lymphodepleting conditioning of patients and ex vivo activation of TILs in adoptive cell transfer. Several strategies are being explored for depletion of

  15. Vibrio campbellii hmgA-mediated pyomelanization impairs quorum sensing, virulence and cellular fitness

    Directory of Open Access Journals (Sweden)

    Zheng eWang

    2013-12-01

    Full Text Available Melanization due to the inactivation of the homogentisate-1,2-dioxygenase gene (hmgA has been demonstrated to increase stress resistance, persistence and virulence in some bacterial species but such pigmented mutants have not been observed in pathogenic members of the Vibrio Harveyi clade. In this study, we used Vibrio campbellii ATCC BAA-1116 as model organism to understand how melanization affected cellular phenotype, metabolism and virulence. An in-frame deletion of the hmgA gene resulted in the overproduction of a pigment in cell culture supernatants and cellular membranes that was identified as pyomelanin. Unlike previous demonstrations in Vibrio cholerae, Burkholderia cepacia and Pseudomonas aeruginosa, the pigmented V. campbellii mutant did not show increased UV resistance and was found to be ~2.7 times less virulent than the wild type strain in Penaeus monodon shrimp virulence assays. However, the extracted pyomelanin pigment did confer a higher resistance to oxidative stress when incubated with wild type cells. Microarray-based transcriptomic analyses revealed that the hmgA gene deletion and subsequent pyomelanin production negatively effected the expression of 129 genes primarily involved in energy production, amino acid and lipid metabolism, and protein translation and turnover. This transcriptional response was mediated in part by an impairment of the quorum sensing regulon as transcripts of the quorum sensing high cell density master regulator LuxR and other operonic members of this regulon were significantly repressed in the hmgA mutant. Taken together, the results suggest that the pyomelanization of V. campbellii sufficiently impairs the metabolic activities of this organism and renders it less fit and virulent than its isogenic wild type strain.

  16. Humoral and Cellular Immune Response in Canine Hypothyroidism.

    Science.gov (United States)

    Miller, J; Popiel, J; Chełmońska-Soyta, A

    2015-07-01

    Hypothyroidism is one of the most common endocrine diseases in dogs and is generally considered to be autoimmune in nature. In human hypothyroidism, the thyroid gland is destroyed by both cellular (i.e. autoreactive helper and cytotoxic T lymphocytes) and humoral (i.e. autoantibodies specific for thyroglobulin, thyroxine and triiodothyronine) effector mechanisms. Other suggested factors include impaired peripheral immune suppression (i.e. the malfunction of regulatory T cells) or an additional pro-inflammatory effect of T helper 17 lymphocytes. The aim of this study was to evaluate immunological changes in canine hypothyroidism. Twenty-eight clinically healthy dogs, 25 hypothyroid dogs without thyroglobulin antibodies and eight hypothyroid dogs with these autoantibodies were enrolled into the study. There were alterations in serum proteins in hypothyroid dogs compared with healthy controls (i.e. raised concentrations of α-globulins, β2- and γ-globulins) as well as higher concentration of acute phase proteins and circulating immune complexes. Hypothyroid animals had a lower CD4:CD8 ratio in peripheral blood compared with control dogs and diseased dogs also had higher expression of interferon γ (gene and protein expression) and CD28 (gene expression). Similar findings were found in both groups of hypothyroid dogs. Canine hypothyroidism is therefore characterized by systemic inflammation with dominance of a cellular immune response.

  17. Biophysical responses upon the interaction of nanomaterials with cellular interfaces.

    Science.gov (United States)

    Wu, Yun-Long; Putcha, Nirupama; Ng, Kee Woei; Leong, David Tai; Lim, Chwee Teck; Loo, Say Chye Joachim; Chen, Xiaodong

    2013-03-19

    The explosion of study of nanomaterials in biological applications (the nano-bio interface) can be ascribed to nanomaterials' growing importance in diagnostics, therapeutics, theranostics (therapeutic diagnostics), and targeted modulation of cellular processes. However, a growing number of critics have raised concerns over the potential risks of nanomaterials to human health and safety. It is essential to understand nanomaterials' potential toxicity before they are tested in humans. These risks are complicated to unravel, however, because of the complexity of cells and their nanoscale macromolecular components, which enable cells to sense and respond to environmental cues, including nanomaterials. In this Account, we explore these risks from the perspective of the biophysical interactions between nanomaterials and cells. Biophysical responses to the uptake of nanomaterials can include conformational changes in biomolecules like DNA and proteins, and changes to the cellular membrane and the cytoskeleton. Changes to the latter two, in particular, can induce changes in cell elasticity, morphology, motility, adhesion, and invasion. This Account reviews what is known about cells' biophysical responses to the uptake of the most widely studied and used nanoparticles, such as carbon-based, metal, metal-oxide, and semiconductor nanomaterials. We postulate that the biophysical structure impairment induced by nanomaterials is one of the key causes of nanotoxicity. The disruption of cellular structures is affected by the size, shape, and chemical composition of nanomaterials, which are also determining factors of nanotoxicity. Currently, popular nanotoxicity characterizations, such as the MTT and lactate dehydrogenase (LDH) assays, only provide end-point results through chemical reactions. Focusing on biophysical structural changes induced by nanomaterials, possibly in real-time, could deepen our understanding of the normal and altered states of subcellular structures and

  18. Cellular immune responses to respiratory viruses

    NARCIS (Netherlands)

    van Helden, M.J.G.

    2011-01-01

    When a respiratory virus successfully infects the lungs, cascades of immune responses are initiated aimed to remove the pathogen. Immediate non-specific protection is provided by the innate immune system and this reduces the viral load during the first days of infection. The adaptive immune response

  19. Endothelial Cellular Responses to Biodegradable Metal Zinc.

    Science.gov (United States)

    Ma, Jun; Zhao, Nan; Zhu, Donghui

    Biodegradable zinc (Zn) metals, a new generation of biomaterials, have attracted much attention due to their excellent biodegradability, bioabsorbability, and adaptability to tissue regeneration. Compared with magnesium (Mg) and iron (Fe), Zn exhibits better corrosion and mechanical behaviors in orthopedic and stent applications. After implantation, Zn containing material will slowly degrade, and Zn ions (Zn(2+)) will be released to the surrounding tissue. For stent applications, the local Zn(2+)concentration near endothelial tissue/cells could be high. However, it is unclear how endothelia will respond to such high concentrations of Zn(2+), which is pivotal to vascular remodeling and regeneration. Here, we evaluated the short-term cellular behaviors of primary human coronary artery endothelial cells (HCECs) exposed to a concentration gradient (0-140 μM) of extracellular Zn(2+). Zn(2+) had an interesting biphasic effect on cell viability, proliferation, spreading, and migration. Generally, low concentrations of Zn(2+) promoted viability, proliferation, adhesion, and migration, while high concentrations of Zn(2+) had opposite effects. For gene expression profiles, the most affected functional genes were related to cell adhesion, cell injury, cell growth, angiogenesis, inflammation, vessel tone, and coagulation. These results provide helpful information and guidance for Zn-based alloy design as well as the controlled release of Zn(2+)in stent and other related medical applications.

  20. Distinct cellular states determine calcium signaling response.

    Science.gov (United States)

    Yao, Jason; Pilko, Anna; Wollman, Roy

    2016-12-15

    The heterogeneity in mammalian cells signaling response is largely a result of pre-existing cell-to-cell variability. It is unknown whether cell-to-cell variability rises from biochemical stochastic fluctuations or distinct cellular states. Here, we utilize calcium response to adenosine trisphosphate as a model for investigating the structure of heterogeneity within a population of cells and analyze whether distinct cellular response states coexist. We use a functional definition of cellular state that is based on a mechanistic dynamical systems model of calcium signaling. Using Bayesian parameter inference, we obtain high confidence parameter value distributions for several hundred cells, each fitted individually. Clustering the inferred parameter distributions revealed three major distinct cellular states within the population. The existence of distinct cellular states raises the possibility that the observed variability in response is a result of structured heterogeneity between cells. The inferred parameter distribution predicts, and experiments confirm that variability in IP3R response explains the majority of calcium heterogeneity. Our work shows how mechanistic models and single-cell parameter fitting can uncover hidden population structure and demonstrate the need for parameter inference at the single-cell level. © 2016 The Authors. Published under the terms of the CC BY 4.0 license.

  1. Cellular stress responses for monitoring and modulating ageing

    DEFF Research Database (Denmark)

    Demirovic, Dino; Schnebert, Sylvianne; Nizard, Carine

    2013-01-01

    Cellular stress response is a crucial factor in maintaining efficient homeodynamics for survival, health and longevity. Both the immediate and delayed responses to external and internal stressors effectively determine the molecular biochemical and physiological stability in a dynamic and interact......Cellular stress response is a crucial factor in maintaining efficient homeodynamics for survival, health and longevity. Both the immediate and delayed responses to external and internal stressors effectively determine the molecular biochemical and physiological stability in a dynamic...... and interactive manner. There are three main aspects of stress responses: (i) immediate stress response involving extra- and intra-cellular signaling during the period of disturbance and exposure to the stressors; (ii) delayed stress response involving sensors and modulators in the presence of stressors or after......, development and ageing. Our aim is to define and establish the immediate and delayed stress profiles of normal human skin fibroblasts undergoing ageing in vitro. This is done efficiently by using various cellular, molecular and antibody-based detection methods, combined with functional assays, such as wound...

  2. Impaired CK1 delta activity attenuates SV40-induced cellular transformation in vitro and mouse mammary carcinogenesis in vivo.

    Directory of Open Access Journals (Sweden)

    Heidrun Hirner

    Full Text Available Simian virus 40 (SV40 is a powerful tool to study cellular transformation in vitro, as well as tumor development and progression in vivo. Various cellular kinases, among them members of the CK1 family, play an important role in modulating the transforming activity of SV40, including the transforming activity of T-Ag, the major transforming protein of SV40, itself. Here we characterized the effects of mutant CK1δ variants with impaired kinase activity on SV40-induced cell transformation in vitro, and on SV40-induced mammary carcinogenesis in vivo in a transgenic/bi-transgenic mouse model. CK1δ mutants exhibited a reduced kinase activity compared to wtCK1δ in in vitro kinase assays. Molecular modeling studies suggested that mutation N172D, located within the substrate binding region, is mainly responsible for impaired mutCK1δ activity. When stably over-expressed in maximal transformed SV-52 cells, CK1δ mutants induced reversion to a minimal transformed phenotype by dominant-negative interference with endogenous wtCK1δ. To characterize the effects of CK1δ on SV40-induced mammary carcinogenesis, we generated transgenic mice expressing mutant CK1δ under the control of the whey acidic protein (WAP gene promoter, and crossed them with SV40 transgenic WAP-T-antigen (WAP-T mice. Both WAP-T mice as well as WAP-mutCK1δ/WAP-T bi-transgenic mice developed breast cancer. However, tumor incidence was lower and life span was significantly longer in WAP-mutCK1δ/WAP-T bi-transgenic animals. The reduced CK1δ activity did not affect early lesion formation during tumorigenesis, suggesting that impaired CK1δ activity reduces the probability for outgrowth of in situ carcinomas to invasive carcinomas. The different tumorigenic potential of SV40 in WAP-T and WAP-mutCK1δ/WAP-T tumors was also reflected by a significantly different expression of various genes known to be involved in tumor progression, specifically of those involved in wnt-signaling and DNA

  3. Modeling In Vitro Cellular Responses to Silver Nanoparticles

    Directory of Open Access Journals (Sweden)

    Dwaipayan Mukherjee

    2014-01-01

    Full Text Available Engineered nanoparticles (NPs have been widely demonstrated to induce toxic effects to various cell types. In vitro cell exposure systems have high potential for reliable, high throughput screening of nanoparticle toxicity, allowing focusing on particular pathways while excluding unwanted effects due to other cells or tissue dosimetry. The work presented here involves a detailed biologically based computational model of cellular interactions with NPs; it utilizes measurements performed in human cell culture systems in vitro, to develop a mechanistic mathematical model that can support analysis and prediction of in vivo effects of NPs. The model considers basic cellular mechanisms including proliferation, apoptosis, and production of cytokines in response to NPs. This new model is implemented for macrophages and parameterized using in vitro measurements of changes in cellular viability and mRNA levels of cytokines: TNF, IL-1b, IL-6, IL-8, and IL-10. The model includes in vitro cellular dosimetry due to nanoparticle transport and transformation. Furthermore, the model developed here optimizes the essential cellular parameters based on in vitro measurements, and provides a “stepping stone” for the development of more advanced in vivo models that will incorporate additional cellular and NP interactions.

  4. Simulating Quantitative Cellular Responses Using Asynchronous Threshold Boolean Network Ensembles

    Science.gov (United States)

    With increasing knowledge about the potential mechanisms underlying cellular functions, it is becoming feasible to predict the response of biological systems to genetic and environmental perturbations. Due to the lack of homogeneity in living tissues it is difficult to estimate t...

  5. Cellular response of Campylobacter jejuni to trisodium phosphate

    DEFF Research Database (Denmark)

    Riedel, Charlotte Tandrup; Cohn, M. T.; Stabler, R. A.

    2012-01-01

    The highly alkaline compound trisodium phosphate (TSP) is used as an intervention to reduce the load of Campylobacter on poultry meat in U.S. poultry slaughter plants. The aim of the present study was to investigate the cellular responses of Campylobacter jejuni NCTC11168 when exposed to sublethal...

  6. Neuroendocrine system response modulates oxidative cellular damage in burn patients.

    Science.gov (United States)

    Xie, Xiao-Qi; Shinozawa, Yotaro; Sasaki, Junichi; Takuma, Kiyotsugu; Akaishi, Satoshi; Yamanouchi, Satoshi; Endo, Tomoyuki; Nomura, Ryosuke; Kobayashi, Michio; Kudo, Daisuke; Hojo, Nobuko

    2007-02-01

    Oxygen-derived free radicals play important roles in pathophysiological processes in critically ill patients, but the data characterizing relationships between radicals and neuroendocrine system response are sparse. To search the cue to reduce the oxidative cellular damage from the point of view of neuroendocrine system response, we studied the indicators of neuroendocrine and inflammatory responses excreted in urine in 14 burn patients (42.3 +/- 31.4 years old, and 32.3 +/- 27.6% burn of total body surface area [%TBSA]) during the first seven days post burn. The daily mean amounts of urinary excretion of 8-hydroxy-2'-deoxy-guanosine (8-OHdG), a marker of oxidative cellular damage, were above the upper limit of the standard value during the studied period. The total amount of urinary excretion of 8-OHdG in the first day post burn correlated with burn severity indices: %TBSA (r = 0.63, p = 0.021) and burn index (r = 0.70, p = 0.008). The daily urinary excretion of 8-OHdG correlated with the daily urinary excretion of norepinephrine and nitrite plus nitrate (NOx) during the studied period except day 2 post burn, and correlated with the daily urinary excretion of 17-hydroxycorticosteriod (17-OHCS) in days 2, 3, and 7 post burn. These data suggest that oxidative cellular damage correlates with burn severity and neuroendocrine system response modulates inflammation and oxidative cellular damage. Modulation of neuroendocrine system response and inflammation in the treatment in the early phase of burn may be useful to reduce the oxidative cellular damage and to prevent multiple organ failures in patients with extensive burn.

  7. Silencing of nicotinamide nucleotide transhydrogenase impairs cellular redox homeostasis and energy metabolism in PC12 cells.

    Science.gov (United States)

    Yin, Fei; Sancheti, Harsh; Cadenas, Enrique

    2012-03-01

    Mitochondrial NADPH generation is largely dependent on the inner-membrane nicotinamide nucleotide transhydrogenase (NNT), which catalyzes the reduction of NADP(+) to NADPH utilizing the proton gradient as the driving force and NADH as the electron donor. Small interfering RNA (siRNA) silencing of NNT in PC12 cells results in decreased cellular NADPH levels, altered redox status of the cell in terms of decreased GSH/GSSG ratios and increased H(2)O(2) levels, thus leading to an increased redox potential (a more oxidized redox state). NNT knockdown results in a decrease of oxidative phosphorylation while anaerobic glycolysis levels remain unchanged. Decreased oxidative phosphorylation was associated with a) inhibition of mitochondrial pyruvate dehydrogenase (PDH) and succinyl-CoA:3-oxoacid CoA transferase (SCOT) activity; b) reduction of NADH availability, c) decline of mitochondrial membrane potential, and d) decrease of ATP levels. Moreover, the alteration of redox status actually precedes the impairment of mitochondrial bioenergetics. A possible mechanism could be that the activation of the redox-sensitive c-Jun N-terminal kinase (JNK) and its translocation to the mitochondrion leads to the inhibition of PDH (upon phosphorylation) and induction of intrinsic apoptosis, resulting in decreased cell viability. This study supports the notion that oxidized cellular redox state and decline in cellular bioenergetics - as a consequence of NNT knockdown - cannot be viewed as independent events, but rather as an interdependent relationship coordinated by the mitochondrial energy-redox axis. Disruption of electron flux from fuel substrates to redox components due to NNT suppression induces not only mitochondrial dysfunction but also cellular disorders through redox-sensitive signaling.

  8. Protein aggregation as a mechanism of adaptive cellular responses.

    Science.gov (United States)

    Saarikangas, Juha; Barral, Yves

    2016-11-01

    Coalescence of proteins into different types of intracellular bodies has surfaced as a widespread adaptive mechanism to re-organize cells and cellular functions in response to specific cues. These structures, composed of proteins or protein-mRNA-complexes, regulate cellular processes through modulating enzymatic activities, gene expression or shielding macromolecules from damage. Accordingly, such bodies are associated with a wide-range of processes, including meiosis, memory-encoding, host-pathogen interactions, cancer, stress responses, as well as protein quality control, DNA replication stress and aneuploidy. Importantly, these distinct coalescence responses are controlled, and in many cases regulated by chaperone proteins. While cells can tolerate and proficiently coordinate numerous distinct types of protein bodies, some of them are also intimately linked to diseases or the adverse effects of aging. Several protein bodies that differ in composition, packing, dynamics, size, and localization were originally discovered in budding yeast. Here, we provide a concise and comparative review of their nature and nomenclature.

  9. KSR2 mutations are associated with obesity, insulin resistance, and impaired cellular fuel oxidation.

    Science.gov (United States)

    Pearce, Laura R; Atanassova, Neli; Banton, Matthew C; Bottomley, Bill; van der Klaauw, Agatha A; Revelli, Jean-Pierre; Hendricks, Audrey; Keogh, Julia M; Henning, Elana; Doree, Deon; Jeter-Jones, Sabrina; Garg, Sumedha; Bochukova, Elena G; Bounds, Rebecca; Ashford, Sofie; Gayton, Emma; Hindmarsh, Peter C; Shield, Julian P H; Crowne, Elizabeth; Barford, David; Wareham, Nick J; O'Rahilly, Stephen; Murphy, Michael P; Powell, David R; Barroso, Ines; Farooqi, I Sadaf

    2013-11-07

    Kinase suppressor of Ras 2 (KSR2) is an intracellular scaffolding protein involved in multiple signaling pathways. Targeted deletion of Ksr2 leads to obesity in mice, suggesting a role in energy homeostasis. We explored the role of KSR2 in humans by sequencing 2,101 individuals with severe early-onset obesity and 1,536 controls. We identified multiple rare variants in KSR2 that disrupt signaling through the Raf-MEKERK pathway and impair cellular fatty acid oxidation and glucose oxidation in transfected cells; effects that can be ameliorated by the commonly prescribed antidiabetic drug, metformin. Mutation carriers exhibit hyperphagia in childhood, low heart rate, reduced basal metabolic rate and severe insulin resistance. These data establish KSR2 as an important regulator of energy intake, energy expenditure, and substrate utilization in humans. Modulation of KSR2-mediated effects may represent a novel therapeutic strategy for obesity and type 2 diabetes.

  10. KSR2 Mutations Are Associated with Obesity, Insulin Resistance, and Impaired Cellular Fuel Oxidation

    Science.gov (United States)

    Pearce, Laura R.; Atanassova, Neli; Banton, Matthew C.; Bottomley, Bill; van der Klaauw, Agatha A.; Revelli, Jean-Pierre; Hendricks, Audrey; Keogh, Julia M.; Henning, Elana; Doree, Deon; Jeter-Jones, Sabrina; Garg, Sumedha; Bochukova, Elena G.; Bounds, Rebecca; Ashford, Sofie; Gayton, Emma; Hindmarsh, Peter C.; Shield, Julian P.H.; Crowne, Elizabeth; Barford, David; Wareham, Nick J.; O’Rahilly, Stephen; Murphy, Michael P.; Powell, David R.; Barroso, Ines; Farooqi, I. Sadaf

    2013-01-01

    Summary Kinase suppressor of Ras 2 (KSR2) is an intracellular scaffolding protein involved in multiple signaling pathways. Targeted deletion of Ksr2 leads to obesity in mice, suggesting a role in energy homeostasis. We explored the role of KSR2 in humans by sequencing 2,101 individuals with severe early-onset obesity and 1,536 controls. We identified multiple rare variants in KSR2 that disrupt signaling through the Raf-MEK-ERK pathway and impair cellular fatty acid oxidation and glucose oxidation in transfected cells; effects that can be ameliorated by the commonly prescribed antidiabetic drug, metformin. Mutation carriers exhibit hyperphagia in childhood, low heart rate, reduced basal metabolic rate and severe insulin resistance. These data establish KSR2 as an important regulator of energy intake, energy expenditure, and substrate utilization in humans. Modulation of KSR2-mediated effects may represent a novel therapeutic strategy for obesity and type 2 diabetes. PaperFlick PMID:24209692

  11. Dynamical theory of active cellular response to external stress

    Science.gov (United States)

    de, Rumi; Safran, Samuel A.

    2008-09-01

    We present a comprehensive, theoretical treatment of the orientational response to external stress of active, contractile cells embedded in a gel-like elastic medium. The theory includes both the forces that arise from the deformation of the matrix as well as forces due to the internal regulation of the stress fibers and focal adhesions of the cell. We calculate the time-dependent response of both the magnitude and the direction of the elastic dipole that characterizes the active forces exerted by the cell, for various situations. For static or quasistatic external stress, cells orient parallel to the stress while for high frequency dynamic external stress, cells orient nearly perpendicular. Both numerical and analytical calculations of these effects are presented. In addition we predict the relaxation time for the cellular response for both slowly and rapidly varying external stresses; several characteristic scaling regimes for the relaxation time as a function of applied frequency are predicted. We also treat the case of cells for which the regulation of the stress fibers and focal adhesions is controlled by strain (instead of stress) and show that the predicted dependence of the cellular orientation on the Poisson ratio of the matrix can differentiate strain vs stress regulation of cellular response.

  12. Dynamical theory of active cellular response to external stress.

    Science.gov (United States)

    De, Rumi; Safran, Samuel A

    2008-09-01

    We present a comprehensive, theoretical treatment of the orientational response to external stress of active, contractile cells embedded in a gel-like elastic medium. The theory includes both the forces that arise from the deformation of the matrix as well as forces due to the internal regulation of the stress fibers and focal adhesions of the cell. We calculate the time-dependent response of both the magnitude and the direction of the elastic dipole that characterizes the active forces exerted by the cell, for various situations. For static or quasistatic external stress, cells orient parallel to the stress while for high frequency dynamic external stress, cells orient nearly perpendicular. Both numerical and analytical calculations of these effects are presented. In addition we predict the relaxation time for the cellular response for both slowly and rapidly varying external stresses; several characteristic scaling regimes for the relaxation time as a function of applied frequency are predicted. We also treat the case of cells for which the regulation of the stress fibers and focal adhesions is controlled by strain (instead of stress) and show that the predicted dependence of the cellular orientation on the Poisson ratio of the matrix can differentiate strain vs stress regulation of cellular response.

  13. Dynamic modeling of cellular response to DNA damage based on p53 stress response networks

    Institute of Scientific and Technical Information of China (English)

    Jinpeng Qi; Yongsheng Ding; Shihuang Shao

    2009-01-01

    Under acute perturbations from the outside, cells can trigger self-defensive mechanisms to fight against genome stress. To investigate the cellular response to continuous ion radiation (IR), a dynamic model for p53 stress response networks at the cellular level is proposed. The model can successfully be used to simulate the dynamic processes of double-strand breaks (DSBs) generation and their repair, switch-like ataxia telangiectasia mutated (ATM) activation, oscillations occurring in the p53-MDM2 feedback loop, as well as toxins elimination triggered by p53 stress response networks. Especially, the model can predict the plausible outcomes of cellular response under different IR dose regimes.

  14. Amyloid-beta leads to impaired cellular respiration, energy production and mitochondrial electron chain complex activities in human neuroblastoma cells.

    Science.gov (United States)

    Rhein, V; Baysang, G; Rao, S; Meier, F; Bonert, A; Müller-Spahn, F; Eckert, A

    2009-09-01

    Evidence suggests that amyloid-beta (Abeta) protein is a key factor in the pathogenesis of Alzheimer's disease (AD) and it has been recently proposed that mitochondria are involved in the biochemical pathway by which Abeta can lead to neuronal dysfunction. Here we investigated the specific effects of Abeta on mitochondrial function under physiological conditions. Mitochondrial respiratory functions and energy metabolism were analyzed in control and in human wild-type amyloid precursor protein (APP) stably transfected human neuroblastoma cells (SH-SY5Y). Mitochondrial respiratory capacity of mitochondrial electron transport chain (ETC) in vital cells was measured with a high-resolution respirometry system (Oxygraph-2k). In addition, we determined the individual activities of mitochondrial complexes I-IV that compose ETC and ATP cellular levels. While the activities of complexes I and II did not change between cell types, complex IV activity was significantly reduced in APP cells. In contrast, activity of complex III was significantly enhanced in APP cells, as compensatory response in order to balance the defect of complex IV. However, this compensatory mechanism could not prevent the strong impairment of total respiration in vital APP cells. As a result, the respiratory control ratio (state3/state4) together with ATP production decreased in the APP cells in comparison with the control cells. Chronic exposure to soluble Abeta protein may result in an impairment of energy homeostasis due to a decreased respiratory capacity of mitochondrial electron transport chain which, in turn, may accelerate neurons demise.

  15. Antioxidant responses and cellular adjustments to oxidative stress

    Science.gov (United States)

    Espinosa-Diez, Cristina; Miguel, Verónica; Mennerich, Daniela; Kietzmann, Thomas; Sánchez-Pérez, Patricia; Cadenas, Susana; Lamas, Santiago

    2015-01-01

    Redox biological reactions are now accepted to bear the Janus faceted feature of promoting both physiological signaling responses and pathophysiological cues. Endogenous antioxidant molecules participate in both scenarios. This review focuses on the role of crucial cellular nucleophiles, such as glutathione, and their capacity to interact with oxidants and to establish networks with other critical enzymes such as peroxiredoxins. We discuss the importance of the Nrf2-Keap1 pathway as an example of a transcriptional antioxidant response and we summarize transcriptional routes related to redox activation. As examples of pathophysiological cellular and tissular settings where antioxidant responses are major players we highlight endoplasmic reticulum stress and ischemia reperfusion. Topologically confined redox-mediated post-translational modifications of thiols are considered important molecular mechanisms mediating many antioxidant responses, whereas redox-sensitive microRNAs have emerged as key players in the posttranscriptional regulation of redox-mediated gene expression. Understanding such mechanisms may provide the basis for antioxidant-based therapeutic interventions in redox-related diseases. PMID:26233704

  16. Innate Cellular Immune Responses in Aedes caspius (Diptera: Culicidae) Mosquitoes.

    Science.gov (United States)

    Soliman, D E; Farid, H A; Hammad, R E; Gad, A M; Bartholomay, L C

    2016-03-01

    Mosquitoes transmit a variety of pathogens that have devastating consequences for global public and veterinary health. Despite their capacity to serve as vectors, these insects have a robust capacity to respond to invading organisms with strong cellular and humoral immune responses. In Egypt, Aedes caspius (Pallas, 1771) has been suspected to act as a bridge vector of Rift Valley Fever virus between animals and humans. Microscopic analysis of Ae. caspius hemolymph revealed the presence of phagocytic cells called granulocytes. We further evaluated cellular immune responses produced by Ae. caspius as a result of exposure to a Gram-negative, and Gram-positive bacterium, and to latex beads. After challenge, a rapid and strong phagocytic response against either a natural or synthetic invader was evident. Hemocyte integrity in bacteria-inoculated mosquitoes was not morphologically affected. The number of circulating granulocytes decreased with age, reducing the overall phagocytic capacity of mosquitoes over time. The magnitude and speed of the phagocytic response suggested that granulocytes act as an important force in the battle against foreign invaders, as has been characterized in other important mosquito vector species.

  17. Antioxidant responses and cellular adjustments to oxidative stress.

    Science.gov (United States)

    Espinosa-Diez, Cristina; Miguel, Verónica; Mennerich, Daniela; Kietzmann, Thomas; Sánchez-Pérez, Patricia; Cadenas, Susana; Lamas, Santiago

    2015-12-01

    Redox biological reactions are now accepted to bear the Janus faceted feature of promoting both physiological signaling responses and pathophysiological cues. Endogenous antioxidant molecules participate in both scenarios. This review focuses on the role of crucial cellular nucleophiles, such as glutathione, and their capacity to interact with oxidants and to establish networks with other critical enzymes such as peroxiredoxins. We discuss the importance of the Nrf2-Keap1 pathway as an example of a transcriptional antioxidant response and we summarize transcriptional routes related to redox activation. As examples of pathophysiological cellular and tissular settings where antioxidant responses are major players we highlight endoplasmic reticulum stress and ischemia reperfusion. Topologically confined redox-mediated post-translational modifications of thiols are considered important molecular mechanisms mediating many antioxidant responses, whereas redox-sensitive microRNAs have emerged as key players in the posttranscriptional regulation of redox-mediated gene expression. Understanding such mechanisms may provide the basis for antioxidant-based therapeutic interventions in redox-related diseases.

  18. Symptoms of Problematic Cellular Phone Use, Functional Impairment and Its Association with Depression among Adolescents in Southern Taiwan

    Science.gov (United States)

    Yen, Cheng-Fang; Tang, Tze-Chun; Yen, Ju-Yu; Lin, Huang-Chi; Huang, Chi-Fen; Liu, Shu-Chun; Ko, Chih-Hung

    2009-01-01

    The aims of this study were: (1) to examine the prevalence of symptoms of problematic cellular phone use (CPU); (2) to examine the associations between the symptoms of problematic CPU, functional impairment caused by CPU and the characteristics of CPU; (3) to establish the optimal cut-off point of the number of symptoms for functional impairment…

  19. Symptoms of Problematic Cellular Phone Use, Functional Impairment and Its Association with Depression among Adolescents in Southern Taiwan

    Science.gov (United States)

    Yen, Cheng-Fang; Tang, Tze-Chun; Yen, Ju-Yu; Lin, Huang-Chi; Huang, Chi-Fen; Liu, Shu-Chun; Ko, Chih-Hung

    2009-01-01

    The aims of this study were: (1) to examine the prevalence of symptoms of problematic cellular phone use (CPU); (2) to examine the associations between the symptoms of problematic CPU, functional impairment caused by CPU and the characteristics of CPU; (3) to establish the optimal cut-off point of the number of symptoms for functional impairment…

  20. Longevity and composition of cellular immune responses following experimental Plasmodium falciparum malaria infection in humans.

    NARCIS (Netherlands)

    Teirlinck, A.C.; McCall, M.B.B.; Roestenberg, M.; Scholzen, A.; Woestenenk, R.M.; Mast, Q. de; Ven, A.J.A.M. van der; Hermsen, C.C.; Luty, A.J.F.; Sauerwein, R.W.

    2011-01-01

    Cellular responses to Plasmodium falciparum parasites, in particular interferon-gamma (IFNgamma) production, play an important role in anti-malarial immunity. However, clinical immunity to malaria develops slowly amongst naturally exposed populations, the dynamics of cellular responses in relation

  1. Impaired innate, humoral, and cellular immunity despite a take in smallpox vaccine recipients.

    Science.gov (United States)

    Kennedy, Richard B; Poland, Gregory A; Ovsyannikova, Inna G; Oberg, Ann L; Asmann, Yan W; Grill, Diane E; Vierkant, Robert A; Jacobson, Robert M

    2016-06-14

    Smallpox vaccine is highly effective, inducing protective immunity to smallpox and diseases caused by related orthopoxviruses. Smallpox vaccine efficacy was historically defined by the appearance of a lesion or "take" at the vaccine site, which leaves behind a characteristic scar. Both the take and scar are readily recognizable and were used during the eradication effort to indicate successful vaccination and to categorize individuals as "protected." However, the development of a typical vaccine take may not equate to the successful development of a robust, protective immune response. In this report, we examined two large (>1000) cohorts of recipients of either Dryvax(®) or ACAM2000 using a testing and replication study design and identified subgroups of individuals who had documented vaccine takes, but who failed to develop robust neutralizing antibody titers. Examination of these individuals revealed that they had suboptimal cellular immune responses as well. Further testing indicated these low responders had a diminished innate antiviral gene expression pattern (IFNA1, CXCL10, CXCL11, OASL) upon in vitro stimulation with vaccinia virus, perhaps indicative of a dysregulated innate response. Our results suggest that poor activation of innate antiviral pathways may result in suboptimal immune responses to the smallpox vaccine. These genes and pathways may serve as suitable targets for adjuvants in new attenuated smallpox vaccines and/or effective antiviral therapy targets against poxvirus infections.

  2. Impaired antiviral response of adenovirus-transformed cell lines supports virus replication.

    Science.gov (United States)

    Bachmann, Mandy; Breitwieser, Theresa; Lipps, Christoph; Wirth, Dagmar; Jordan, Ingo; Reichl, Udo; Frensing, Timo

    2016-02-01

    Activation of the innate immune response represents one of the most important cellular mechanisms to limit virus replication and spread in cell culture. Here, we examined the effect of adenoviral gene expression on the antiviral response in adenovirus-transformed cell lines; HEK293, HEK293SF and AGE1.HN. We demonstrate that the expression of the early region protein 1A in these cell lines impairs their ability to activate antiviral genes by the IFN pathway. This property may help in the isolation of newly emerging viruses and the propagation of interferon-sensitive virus strains.

  3. The cellular bases of antibody responses during dengue virus infection

    Directory of Open Access Journals (Sweden)

    Juan Carlos Yam-Puc

    2016-06-01

    Full Text Available Dengue virus (DENV is one of the most significant human viral pathogens transmitted by mosquitoes and can cause from an asymptomatic disease to mild undifferentiated fever, classical dengue, and severe dengue. Neutralizing memory antibody (Ab responses are one of the most important mechanisms that counteract reinfections and are therefore the main aim of vaccination. However, it has also been proposed that in dengue, some of these class-switched (IgG memory Abs might worsen the disease. Although these memory Abs derive from B cells by T-cell dependent processes, we know rather little about the (acute, chronic or memory B cell responses and the complex cellular mechanisms generating these Abs during DENV infections.This review aims to provide an updated and comprehensive perspective of the B cell responses during DENV infection, starting since the very early events like the cutaneous DENV entrance and the arrival into draining lymph nodes, to the putative B cell activation, proliferation and germinal centers (GCs formation (the source of affinity-matured class-switched memory Abs, till the outcome of GC reactions such as the generation of plasmablasts, Ab-secreting plasma cells and memory B cells. We discuss topics very poorly explored such as the possibility of B cell infection by DENV or even activation-induced B cell death. The current information about the nature of the Ab responses to DENV is also illustrated.

  4. Simulating Quantitative Cellular Responses Using Asynchronous Threshold Boolean Network Ensembles

    Directory of Open Access Journals (Sweden)

    Shah Imran

    2011-07-01

    Full Text Available Abstract Background With increasing knowledge about the potential mechanisms underlying cellular functions, it is becoming feasible to predict the response of biological systems to genetic and environmental perturbations. Due to the lack of homogeneity in living tissues it is difficult to estimate the physiological effect of chemicals, including potential toxicity. Here we investigate a biologically motivated model for estimating tissue level responses by aggregating the behavior of a cell population. We assume that the molecular state of individual cells is independently governed by discrete non-deterministic signaling mechanisms. This results in noisy but highly reproducible aggregate level responses that are consistent with experimental data. Results We developed an asynchronous threshold Boolean network simulation algorithm to model signal transduction in a single cell, and then used an ensemble of these models to estimate the aggregate response across a cell population. Using published data, we derived a putative crosstalk network involving growth factors and cytokines - i.e., Epidermal Growth Factor, Insulin, Insulin like Growth Factor Type 1, and Tumor Necrosis Factor α - to describe early signaling events in cell proliferation signal transduction. Reproducibility of the modeling technique across ensembles of Boolean networks representing cell populations is investigated. Furthermore, we compare our simulation results to experimental observations of hepatocytes reported in the literature. Conclusion A systematic analysis of the results following differential stimulation of this model by growth factors and cytokines suggests that: (a using Boolean network ensembles with asynchronous updating provides biologically plausible noisy individual cellular responses with reproducible mean behavior for large cell populations, and (b with sufficient data our model can estimate the response to different concentrations of extracellular ligands. Our

  5. The DNA damage response in viral-induced cellular transformation.

    Science.gov (United States)

    Nikitin, P A; Luftig, M A

    2012-01-31

    The DNA damage response (DDR) has emerged as a critical tumour suppressor pathway responding to cellular DNA replicative stress downstream of aberrant oncogene over-expression. Recent studies have now implicated the DDR as a sensor of oncogenic virus infection. In this review, we discuss the mechanisms by which tumour viruses activate and also suppress the host DDR. The mechanism of tumour virus induction of the DDR is intrinsically linked to the need for these viruses to promote an S-phase environment to replicate their nucleic acid during infection. However, inappropriate expression of viral oncoproteins can also activate the DDR through various mechanisms including replicative stress, direct interaction with DDR components and induction of reactive oxygen species. Given the growth-suppressive consequences of activating the DDR, tumour viruses have also evolved mechanisms to attenuate these pathways. Aberrant expression of viral oncoproteins may therefore promote tumourigenesis through increased somatic mutation and aneuploidy due to DDR inactivation. This review will focus on the interplay between oncogenic viruses and the DDR with respect to cellular checkpoint control and transformation.

  6. Local Cellular Responses to Titanium Dioxide from Orthopedic Implants

    Directory of Open Access Journals (Sweden)

    Jie J. Yao

    2017-07-01

    Full Text Available We evaluated recently published articles relevant to the biological effects of titanium dioxide (TiO2 particles on local endogenous cells required for normal bone homeostasis, repair, and implant osseointegration. Structural characteristics, size, stability, and agglomeration of TiO2 particles alter the viability and behavior of multiple bone-related cell types. Resulting shifts in bone homeostasis may increase bone resorption and lead to clinical incidents of osteolysis, implant loosening, and joint pain. TiO2 particles that enter cells (through endocytosis or Trojan horse mechanism may further disrupt implant retention. We propose that cellular responses to titanium-based nanoparticles contribute to pathological mechanisms underlying the aseptic loosening of titanium-based metal implants.

  7. Innate and Adaptive Cellular Immune Responses to Mycobacterium tuberculosis Infection.

    Science.gov (United States)

    Mayer-Barber, Katrin D; Barber, Daniel L

    2015-07-17

    Host resistance to Mycobacterium tuberculosis (Mtb) infection requires the coordinated efforts of innate and adaptive immune cells. Diverse pulmonary myeloid cell populations respond to Mtb with unique contributions to both host-protective and potentially detrimental inflammation. Although multiple cell types of the adaptive immune system respond to Mtb infection, CD4 T cells are the principal antigen-specific cells responsible for containment of Mtb infection, but they can also be major contributors to disease during Mtb infection in several different settings. Here, we will discuss the role of different myeloid populations as well as the dual nature of CD4 T cells in Mtb infection with a primary focus on data generated using in vivo cellular immunological studies in experimental animal models and in humans when available. Copyright © 2015 Cold Spring Harbor Laboratory Press; all rights reserved.

  8. MOF maintains transcriptional programs regulating cellular stress response.

    Science.gov (United States)

    Sheikh, B N; Bechtel-Walz, W; Lucci, J; Karpiuk, O; Hild, I; Hartleben, B; Vornweg, J; Helmstädter, M; Sahyoun, A H; Bhardwaj, V; Stehle, T; Diehl, S; Kretz, O; Voss, A K; Thomas, T; Manke, T; Huber, T B; Akhtar, A

    2016-05-01

    MOF (MYST1, KAT8) is the major H4K16 lysine acetyltransferase (KAT) in Drosophila and mammals and is essential for embryonic development. However, little is known regarding the role of MOF in specific cell lineages. Here we analyze the differential role of MOF in proliferating and terminally differentiated tissues at steady state and under stress conditions. In proliferating cells, MOF directly binds and maintains the expression of genes required for cell cycle progression. In contrast, MOF is dispensable for terminally differentiated, postmitotic glomerular podocytes under physiological conditions. However, in response to injury, MOF is absolutely critical for podocyte maintenance in vivo. Consistently, we detect defective nuclear, endoplasmic reticulum and Golgi structures, as well as presence of multivesicular bodies in vivo in podocytes lacking Mof following injury. Undertaking genome-wide expression analysis of podocytes, we uncover several MOF-regulated pathways required for stress response. We find that MOF, along with the members of the non-specific lethal but not the male-specific lethal complex, directly binds to genes encoding the lysosome, endocytosis and vacuole pathways, which are known regulators of podocyte maintenance. Thus, our work identifies MOF as a key regulator of cellular stress response in glomerular podocytes.

  9. Insights into the cellular responses to hypoxia in filamentous fungi.

    Science.gov (United States)

    Hillmann, Falk; Shekhova, Elena; Kniemeyer, Olaf

    2015-08-01

    Most eukaryotes require molecular oxygen for growth. In general, oxygen is the terminal electron acceptor of the respiratory chain and represents an important substrate for the biosynthesis of cellular compounds. However, in their natural environment, such as soil, and also during the infection, filamentous fungi are confronted with low levels of atmospheric oxygen. Transcriptome and proteome studies on the hypoxic response of filamentous fungi revealed significant alteration of the gene expression and protein synthesis upon hypoxia. These analyses discovered not only common but also species-specific responses to hypoxia with regard to NAD(+) regeneration systems and other metabolic pathways. A surprising outcome was that the induction of oxidative and nitrosative stress defenses during oxygen limitation represents a general trait of adaptation to hypoxia in many fungi. The interplay of these different stress responses is poorly understood, but recent studies have shown that adaptation to hypoxia contributes to virulence of pathogenic fungi. In this review, results on metabolic changes of filamentous fungi during adaptation to hypoxia are summarized and discussed.

  10. Mechano-biological Coupling of Cellular Responses to Microgravity

    Science.gov (United States)

    Long, Mian; Wang, Yuren; Zheng, Huiqiong; Shang, Peng; Duan, Enkui; Lü, Dongyuan

    2015-11-01

    Cellular response to microgravity is a basic issue in space biological sciences as well as space physiology and medicine. It is crucial to elucidate the mechano-biological coupling mechanisms of various biological organisms, since, from the principle of adaptability, all species evolved on the earth must possess the structure and function that adapts their living environment. As a basic element of an organism, a cell usually undergoes mechanical and chemical remodeling to sense, transmit, transduce, and respond to the alteration of gravitational signals. In the past decades, new computational platforms and experimental methods/techniques/devices are developed to mimic the biological effects of microgravity environment from the viewpoint of biomechanical approaches. Mechanobiology of plant gravisensing in the responses of statolith movements along the gravity vector and the relevant signal transduction and molecular regulatory mechanisms are investigated at gene, transcription, and protein levels. Mechanotransduction of bone or immune cell responses and stem cell development and tissue histogenesis are elucidated under microgravity. In this review, several important issues are briefly discussed. Future issues on gravisensing and mechanotransducing mechanisms are also proposed for ground-based studies as well as space missions.

  11. Different Candida parapsilosis clinical isolates and lipase deficient strain trigger an altered cellular immune response

    Directory of Open Access Journals (Sweden)

    Renata eToth

    2015-10-01

    Full Text Available Numerous human diseases can be associated with fungal infections either as potential causative agents or as a result of changed immune status due to a primary disease. Fungal infections caused by Candida species can vary from mild to severe dependent upon the site of infection, length of exposure and past medical history. Patients with impaired immune status are at increased risk for chronic fungal infections. Recent epidemiologic studies have revealed the increasing incidence of candidiasis caused by non-albicans species such as C. parapsilosis. Due to its increasing relevance we chose two distinct C. parapsilosis strains, to describe the cellular innate immune response towards this species. In the first section of our study we compared the interaction of CLIB 214 and GA1 cells with murine and human macrophages. Both strains are commonly used to investigate C. parapsilosis virulence properties. CLIB 214 is a rapidly pseudohyphae-forming strain and GA1 is an isolate that mainly exists in a yeast form. Our results showed, that the phagocyte response was similar in terms of overall uptake, however differences were observed in macrophage migration and engulfment of fungal cells. As C. parapsilosis releases extracellular lipases in order to promote host invasion we further investigated the role of these secreted components during the distinct stages of the phagocytic process. Using a secreted lipase deficient mutant strain and the parental strain GA1 individually and simultaneously, we confirmed that fungal secreted lipases influence the fungi’s virulence by detecting altered innate cellular responses.In this study we report that two isolates of a single species can trigger markedly distinct host responses and that lipase secretion plays a role on the cellular level of host pathogen interactions.

  12. Robust network topologies for generating switch-like cellular responses.

    Directory of Open Access Journals (Sweden)

    Najaf A Shah

    2011-06-01

    Full Text Available Signaling networks that convert graded stimuli into binary, all-or-none cellular responses are critical in processes ranging from cell-cycle control to lineage commitment. To exhaustively enumerate topologies that exhibit this switch-like behavior, we simulated all possible two- and three-component networks on random parameter sets, and assessed the resulting response profiles for both steepness (ultrasensitivity and extent of memory (bistability. Simulations were used to study purely enzymatic networks, purely transcriptional networks, and hybrid enzymatic/transcriptional networks, and the topologies in each class were rank ordered by parametric robustness (i.e., the percentage of applied parameter sets exhibiting ultrasensitivity or bistability. Results reveal that the distribution of network robustness is highly skewed, with the most robust topologies clustering into a small number of motifs. Hybrid networks are the most robust in generating ultrasensitivity (up to 28% and bistability (up to 18%; strikingly, a purely transcriptional framework is the most fragile in generating either ultrasensitive (up to 3% or bistable (up to 1% responses. The disparity in robustness among the network classes is due in part to zero-order ultrasensitivity, an enzyme-specific phenomenon, which repeatedly emerges as a particularly robust mechanism for generating nonlinearity and can act as a building block for switch-like responses. We also highlight experimentally studied examples of topologies enabling switching behavior, in both native and synthetic systems, that rank highly in our simulations. This unbiased approach for identifying topologies capable of a given response may be useful in discovering new natural motifs and in designing robust synthetic gene networks.

  13. Ethanol cellular defense induce unfolded protein response in yeast

    Directory of Open Access Journals (Sweden)

    Elisabet eNavarro-Tapia

    2016-02-01

    Full Text Available Ethanol is a valuable industrial product and a common metabolite used by many cell types. However, this molecule produces high levels of cytotoxicity affecting cellular performance at several levels. In the presence of ethanol, cells must adjust some of their components, such as the membrane lipids to maintain homeostasis. In the case of microorganism as Saccharomyces cerevisiae, ethanol is one of the principal products of their metabolism and is the main stress factor during fermentation. Although many efforts have been made, mechanisms of ethanol tolerance are not fully understood and very little evidence is available to date for specific signaling by ethanol in the cell. This work studied two Saccharomyces cerevisiae strains, CECT10094 and Temohaya-MI26, isolated from flor wine and agave fermentation (a traditional fermentation from Mexico respectively, which differ in ethanol tolerance, in order to understand the molecular mechanisms underlying the ethanol stress response and the reasons for different ethanol tolerance. The transcriptome was analyzed after ethanol stress and, among others, an increased activation of genes related with the unfolded protein response (UPR and its transcription factor, Hac1p, was observed in the tolerant strain CECT10094. We observed that this strain also resist more UPR agents than Temohaya-MI26 and the UPR-ethanol stress correlation was corroborated observing growth of 15 more strains and discarding UPR correlation with other stresses as thermal or oxidative stress. Furthermore, higher activation of UPR pathway in the tolerant strain CECT10094 was observed using a UPR mCherry reporter. Finally, we observed UPR activation in response to ethanol stress in other S. cerevisiae ethanol tolerant strains as the wine strains T73 and EC1118. This work demonstrates that the UPR pathway is activated under ethanol stress occurring in a standard fermentation and links this response to an enhanced ethanol tolerance. Thus

  14. Conversational Responsiveness and Assertiveness in Language-Impaired Children.

    Science.gov (United States)

    Rosinski-McClendon, Mary Kay; Newhoff, Marilyn

    1987-01-01

    The conversational responsiveness and assertiveness of 10 language-disordered children (4:1 to 5:9 years old) was compared to that of 10 non-impaired younger children matched for language ability. Results indicated that the handicapped children responded to questions less often but were as assertive in conversation as normal children. (DB)

  15. Care Partner Responses to the Onset of Mild Cognitive Impairment

    Science.gov (United States)

    Blieszner, Rosemary; Roberto, Karen A.

    2010-01-01

    Purpose: We examined characteristics, responses, and psychological well-being of care partners who support and assist older adults recently diagnosed with mild cognitive impairment (MCI). Design and Methods: Based on a sample of 106 care partners of community residents diagnosed with MCI at memory clinics, we conducted face-to-face interviews…

  16. Cellular Mechanisms of Gravitropic Response in Higher Plants

    Science.gov (United States)

    Medvedev, Sergei; Smolikova, Galina; Pozhvanov, Gregory; Suslov, Dmitry

    The evolutionary success of land plants in adaptation to the vectorial environmental factors was based mainly on the development of polarity systems. In result, normal plant ontogenesis is based on the positional information. Polarity is a tool by which the developing plant organs and tissues are mapped and the specific three-dimensional structure of the organism is created. It is due to their polar organization plants are able to orient themselves relative to the gravity vector and different vectorial cues, and to respond adequately to various stimuli. Gravitation is one of the most important polarized environmental factor that guides the development of plant organisms in space. Every plant can "estimate" its position relative to the gravity vector and correct it, if necessary, by means of polarized growth. The direction and the magnitude of gravitational stimulus are constant during the whole plant ontogenesis. The key plant response to the action of gravity is gravitropism, i.e. the directed growth of organs with respect to the gravity vector. This response is a very convenient model to study the mechanisms of plant orientation in space. The present report is focused on the main cellular mechanisms responsible for graviropic bending in higher plants. These mechanisms and structures include electric polarization of plant cells, Ca ({2+) }gradients, cytoskeleton, G-proteins, phosphoinositides and the machinery responsible for asymmetric auxin distribution. Those mechanisms tightly interact demonstrating some hierarchy and multiple feedbacks. The Ca (2+) gradients provide the primary physiological basis of polarity in plant cells. Calcium ions influence on the bioelectric potentials, the organization of actin cytoskeleton, the activity of Ca (2+) -binding proteins and Ca (2+) -dependent protein kinases. Protein kinases modulate transcription factors activity thereby regulating the gene expression and switching the developmental programs. Actin cytoskeleton affects

  17. Semantic annotation of biological concepts interplaying microbial cellular responses

    Directory of Open Access Journals (Sweden)

    Carreira Rafael

    2011-11-01

    Full Text Available Abstract Background Automated extraction systems have become a time saving necessity in Systems Biology. Considerable human effort is needed to model, analyse and simulate biological networks. Thus, one of the challenges posed to Biomedical Text Mining tools is that of learning to recognise a wide variety of biological concepts with different functional roles to assist in these processes. Results Here, we present a novel corpus concerning the integrated cellular responses to nutrient starvation in the model-organism Escherichia coli. Our corpus is a unique resource in that it annotates biomedical concepts that play a functional role in expression, regulation and metabolism. Namely, it includes annotations for genetic information carriers (genes and DNA, RNA molecules, proteins (transcription factors, enzymes and transporters, small metabolites, physiological states and laboratory techniques. The corpus consists of 130 full-text papers with a total of 59043 annotations for 3649 different biomedical concepts; the two dominant classes are genes (highest number of unique concepts and compounds (most frequently annotated concepts, whereas other important cellular concepts such as proteins account for no more than 10% of the annotated concepts. Conclusions To the best of our knowledge, a corpus that details such a wide range of biological concepts has never been presented to the text mining community. The inter-annotator agreement statistics provide evidence of the importance of a consolidated background when dealing with such complex descriptions, the ambiguities naturally arising from the terminology and their impact for modelling purposes. Availability is granted for the full-text corpora of 130 freely accessible documents, the annotation scheme and the annotation guidelines. Also, we include a corpus of 340 abstracts.

  18. Herpesviral microRNAs in Cellular Metabolism and Immune Responses

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    Hyoji Kim

    2017-07-01

    Full Text Available The microRNAs (miRNAs function as a key regulator in many biological processes through post-transcriptional suppression of messenger RNAs. Recent advancements have revealed that miRNAs are involved in many biological functions of cells. Not only host cells, but also some viruses encode miRNAs in their genomes. Viral miRNAs regulate cell proliferation, differentiation, apoptosis, and the cell cycle to establish infection and produce viral progeny. Particularly, miRNAs encoded by herpes virus families play integral roles in persistent viral infection either by regulation of metabolic processes or the immune response of host cells. The life-long persistent infection of gamma herpes virus subfamilies, such as Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus, induces host cells to malignant transformation. The unbalanced metabolic processes and evasion from host immune surveillance by viral miRNAs are induced either by direct targeting of key proteins or indirect regulation of multiple signaling pathways. We provide an overview of the pathogenic roles of viral miRNAs in cellular metabolism and immune responses during herpesvirus infection.

  19. Ploidy influences cellular responses to gross chromosomal rearrangements in saccharomyces cerevisiae

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    Lemoine Sophie

    2011-06-01

    Full Text Available Abstract Background Gross chromosomal rearrangements (GCRs such as aneuploidy are key factors in genome evolution as well as being common features of human cancer. Their role in tumour initiation and progression has not yet been completely elucidated and the effects of additional chromosomes in cancer cells are still unknown. Most previous studies in which Saccharomyces cerevisiae has been used as a model for cancer cells have been carried out in the haploid context. To obtain new insights on the role of ploidy, the cellular effects of GCRs were compared between the haploid and diploid contexts. Results A total number of 21 haploid and diploid S. cerevisiae strains carrying various types of GCRs (aneuploidies, nonreciprocal translocations, segmental duplications and deletions were studied with a view to determining the effects of ploidy on the cellular responses. Differences in colony and cell morphology as well as in the growth rates were observed between mutant and parental strains. These results suggest that cells are impaired physiologically in both contexts. We also investigated the variation in genomic expression in all the mutants. We observed that gene expression was significantly altered. The data obtained here clearly show that genes involved in energy metabolism, especially in the tricarboxylic acid cycle, are up-regulated in all these mutants. However, the genes involved in the composition of the ribosome or in RNA processing are down-regulated in diploids but up-regulated in haploids. Over-expression of genes involved in the regulation of the proteasome was found to occur only in haploid mutants. Conclusion The present comparisons between the cellular responses of strains carrying GCRs in different ploidy contexts bring to light two main findings. First, GCRs induce a general stress response in all studied mutants, regardless of their ploidy. Secondly, the ploidy context plays a crucial role in maintaining the stoichiometric balance

  20. Cellular Pathways in Response to Ionizing Radiation and Their Targetability for Tumor Radiosensitization.

    Science.gov (United States)

    Maier, Patrick; Hartmann, Linda; Wenz, Frederik; Herskind, Carsten

    2016-01-14

    During the last few decades, improvements in the planning and application of radiotherapy in combination with surgery and chemotherapy resulted in increased survival rates of tumor patients. However, the success of radiotherapy is impaired by two reasons: firstly, the radioresistance of tumor cells and, secondly, the radiation-induced damage of normal tissue cells located in the field of ionizing radiation. These limitations demand the development of drugs for either radiosensitization of tumor cells or radioprotection of normal tissue cells. In order to identify potential targets, a detailed understanding of the cellular pathways involved in radiation response is an absolute requirement. This review describes the most important pathways of radioresponse and several key target proteins for radiosensitization.

  1. Cellular Pathways in Response to Ionizing Radiation and Their Targetability for Tumor Radiosensitization

    Directory of Open Access Journals (Sweden)

    Patrick Maier

    2016-01-01

    Full Text Available During the last few decades, improvements in the planning and application of radiotherapy in combination with surgery and chemotherapy resulted in increased survival rates of tumor patients. However, the success of radiotherapy is impaired by two reasons: firstly, the radioresistance of tumor cells and, secondly, the radiation-induced damage of normal tissue cells located in the field of ionizing radiation. These limitations demand the development of drugs for either radiosensitization of tumor cells or radioprotection of normal tissue cells. In order to identify potential targets, a detailed understanding of the cellular pathways involved in radiation response is an absolute requirement. This review describes the most important pathways of radioresponse and several key target proteins for radiosensitization.

  2. A Computational Model of Cellular Response to Modulated Radiation Fields

    Energy Technology Data Exchange (ETDEWEB)

    McMahon, Stephen J., E-mail: stephen.mcmahon@qub.ac.uk [Centre for Cancer Research and Cell Biology, Queen' s University Belfast, Belfast, Northern Ireland (United Kingdom); Butterworth, Karl T. [Centre for Cancer Research and Cell Biology, Queen' s University Belfast, Belfast, Northern Ireland (United Kingdom); McGarry, Conor K. [Centre for Cancer Research and Cell Biology, Queen' s University Belfast, Belfast, Northern Ireland (United Kingdom); Radiotherapy Physics, Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Northern Ireland (United Kingdom); Trainor, Colman [Centre for Cancer Research and Cell Biology, Queen' s University Belfast, Belfast, Northern Ireland (United Kingdom); O' Sullivan, Joe M. [Centre for Cancer Research and Cell Biology, Queen' s University Belfast, Belfast, Northern Ireland (United Kingdom); Clinical Oncology, Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Belfast, Northern Ireland (United Kingdom); Hounsell, Alan R. [Centre for Cancer Research and Cell Biology, Queen' s University Belfast, Belfast, Northern Ireland (United Kingdom); Radiotherapy Physics, Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Northern Ireland (United Kingdom); Prise, Kevin M. [Centre for Cancer Research and Cell Biology, Queen' s University Belfast, Belfast, Northern Ireland (United Kingdom)

    2012-09-01

    Purpose: To develop a model to describe the response of cell populations to spatially modulated radiation exposures of relevance to advanced radiotherapies. Materials and Methods: A Monte Carlo model of cellular radiation response was developed. This model incorporated damage from both direct radiation and intercellular communication including bystander signaling. The predictions of this model were compared to previously measured survival curves for a normal human fibroblast line (AGO1522) and prostate tumor cells (DU145) exposed to spatially modulated fields. Results: The model was found to be able to accurately reproduce cell survival both in populations which were directly exposed to radiation and those which were outside the primary treatment field. The model predicts that the bystander effect makes a significant contribution to cell killing even in uniformly irradiated cells. The bystander effect contribution varies strongly with dose, falling from a high of 80% at low doses to 25% and 50% at 4 Gy for AGO1522 and DU145 cells, respectively. This was verified using the inducible nitric oxide synthase inhibitor aminoguanidine to inhibit the bystander effect in cells exposed to different doses, which showed significantly larger reductions in cell killing at lower doses. Conclusions: The model presented in this work accurately reproduces cell survival following modulated radiation exposures, both in and out of the primary treatment field, by incorporating a bystander component. In addition, the model suggests that the bystander effect is responsible for a significant portion of cell killing in uniformly irradiated cells, 50% and 70% at doses of 2 Gy in AGO1522 and DU145 cells, respectively. This description is a significant departure from accepted radiobiological models and may have a significant impact on optimization of treatment planning approaches if proven to be applicable in vivo.

  3. Cellular basis for the olfactory response to nicotine.

    Science.gov (United States)

    Bryant, Bruce; Xu, Jiang; Audige, Valery; Lischka, Fritz W; Rawson, Nancy E

    2010-03-17

    Smokers regulate their smoking behavior on the basis of sensory stimuli independently of the pharmacological effects of nicotine (Rose J. E., et al. (1993) Pharmacol., Biochem. Behav.44 (4), 891-900). A better understanding of sensory mechanisms underlying smoking behavior may help to develop more effective smoking alternatives. Olfactory stimulation by nicotine makes up a considerable part of the flavor of tobacco smoke, yet our understanding of the cellular mechanisms responsible for olfactory detection of nicotine remains incomplete. We used biophysical methods to characterize the nicotine sensitivity and response mechanisms of neurons from olfactory epithelium. In view of substantial differences in the olfactory receptor repertoire between rodent and human (Mombaerts P. (1999) Annu. Rev. Neurosci.22, 487-509), we studied biopsied human olfactory sensory neurons (OSNs), cultured human olfactory cells (Gomez G., et al. (2000) J. Neurosci. Res.62 (5), 737-749), and rat olfactory neurons. Rat and human OSNs responded to S(-)-nicotine with a concentration dependent influx of calcium and activation of adenylate cyclase. Some rat OSNs displayed some stereoselectivity, with neurons responding to either enantiomer alone or to both. Freshly biopsied and primary cultured human olfactory neurons were less stereoselective. Nicotinic cholinergic antagonists had no effect on the responses of rat or human OSNs to nicotine. Patch clamp recording of rat OSNs revealed a nicotine-activated, calcium-sensitive nonspecific cation channel. These results indicate that nicotine activates a canonical olfactory receptor pathway rather than nicotinic cholinergic receptors on OSNs. Further, because the nicotine-sensitive mechanisms of rodents appear generally similar to those of humans, this animal model is an appropriate one for studies of nicotine sensation.

  4. Investigating the Cellular and Metabolic Responses of World-Class Canoeists Training: A Sportomics Approach

    Science.gov (United States)

    Coelho, Wagner Santos; Viveiros de Castro, Luis; Deane, Elizabeth; Magno-França, Alexandre; Bassini, Adriana; Cameron, Luiz-Claudio

    2016-01-01

    (1) Background: We have been using the Sportomics approach to evaluate biochemical and hematological changes in response to exercise. The aim of this study was to evaluate the metabolic and hematologic responses of world-class canoeists during a training session; (2) Methods: Blood samples were taken at different points and analyzed for their hematological properties, activities of selected enzymes, hormones, and metabolites; (3) Results: Muscle stress biomarkers were elevated in response to exercise which correlated with modifications in the profile of white blood cells, where a leukocyte rise was observed after the canoe session. These results were accompanied by an increase in other exercise intensity parameters such as lactatemia and ammonemia. Adrenocorticotropic hormone and cortisol increased during the exercise sessions. The acute rise in both erythrocytes and white blood profile were probably due to muscle cell damage, rather than hepatocyte integrity impairment; (4) Conclusion: The cellular and metabolic responses found here, together with effective nutrition support, are crucial to understanding the effects of exercise in order to assist in the creation of new training and recovery planning. Also we show that Sportomics is a primal tool for training management and performance improvement, as well as to the understanding of metabolic response to exercise. PMID:27845704

  5. Investigating the Cellular and Metabolic Responses of World-Class Canoeists Training: A Sportomics Approach

    Directory of Open Access Journals (Sweden)

    Wagner Santos Coelho

    2016-11-01

    Full Text Available (1 Background: We have been using the Sportomics approach to evaluate biochemical and hematological changes in response to exercise. The aim of this study was to evaluate the metabolic and hematologic responses of world-class canoeists during a training session; (2 Methods: Blood samples were taken at different points and analyzed for their hematological properties, activities of selected enzymes, hormones, and metabolites; (3 Results: Muscle stress biomarkers were elevated in response to exercise which correlated with modifications in the profile of white blood cells, where a leukocyte rise was observed after the canoe session. These results were accompanied by an increase in other exercise intensity parameters such as lactatemia and ammonemia. Adrenocorticotropic hormone and cortisol increased during the exercise sessions. The acute rise in both erythrocytes and white blood profile were probably due to muscle cell damage, rather than hepatocyte integrity impairment; (4 Conclusion: The cellular and metabolic responses found here, together with effective nutrition support, are crucial to understanding the effects of exercise in order to assist in the creation of new training and recovery planning. Also we show that Sportomics is a primal tool for training management and performance improvement, as well as to the understanding of metabolic response to exercise.

  6. The importance of the cellular stress response in the pathogenesis and treatment of type 2 diabetes.

    Science.gov (United States)

    Hooper, Philip L; Balogh, Gabor; Rivas, Eric; Kavanagh, Kylie; Vigh, Laszlo

    2014-07-01

    Organisms have evolved to survive rigorous environments and are not prepared to thrive in a world of caloric excess and sedentary behavior. A realization that physical exercise (or lack of it) plays a pivotal role in both the pathogenesis and therapy of type 2 diabetes mellitus (t2DM) has led to the provocative concept of therapeutic exercise mimetics. A decade ago, we attempted to simulate the beneficial effects of exercise by treating t2DM patients with 3 weeks of daily hyperthermia, induced by hot tub immersion. The short-term intervention had remarkable success, with a 1 % drop in HbA1, a trend toward weight loss, and improvement in diabetic neuropathic symptoms. An explanation for the beneficial effects of exercise and hyperthermia centers upon their ability to induce the cellular stress response (the heat shock response) and restore cellular homeostasis. Impaired stress response precedes major metabolic defects associated with t2DM and may be a near seminal event in the pathogenesis of the disease, tipping the balance from health into disease. Heat shock protein inducers share metabolic pathways associated with exercise with activation of AMPK, PGC1-a, and sirtuins. Diabetic therapies that induce the stress response, whether via heat, bioactive compounds, or genetic manipulation, improve or prevent all of the morbidities and comorbidities associated with the disease. The agents reduce insulin resistance, inflammatory cytokines, visceral adiposity, and body weight while increasing mitochondrial activity, normalizing membrane structure and lipid composition, and preserving organ function. Therapies restoring the stress response can re-tip the balance from disease into health and address the multifaceted defects associated with the disease.

  7. Microtubule modification influences cellular response to amyloid-β exposure

    Directory of Open Access Journals (Sweden)

    Nicole Shamitko-Klingensmith

    2016-05-01

    Full Text Available During the normal aging process, cytoskeletal changes such as a reduction in density or disruption of cytoskeletal components occur that can affect neuronal function. As aging is the biggest risk factor for Alzheimer's disease (AD, this study sought to determine how microtubule (MT modification influences cellular response upon exposure to β-amyloid1-42 (Aβ1-42, which is implicated in AD. The MT networks of hypothalamic GT1-7 neurons were modified by common disrupting or stabilizing drugs, and then the physical and mechanical properties of the modified neurons were determined. The MT modified neurons were then exposed to Aβ1-42 and the ability of the neurons to cope with this exposure was determined by a variety of biochemical assays. Flow cytometry studies indicated that MT disruption reduced the binding of Aβ1-42 to the plasma membrane by 45% per cell compared to neurons with stabilized or unaltered MTs. Although the cells with disrupted MTs experienced less peptide-membrane binding, they experienced similar or increased levels of cytotoxicity caused by the Aβ1-42 exposure. In contrast, MT stabilization delayed toxicity caused by Aβ1-42. These results demonstrate that MT modification significantly influences the ability of neurons to cope with toxicity induced by Aβ1-42.

  8. Psychophysical evidence for impaired Magno, Parvo, and Konio-cellular pathways in dyslexic children

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    Khazar Ahmadi

    2015-01-01

    Conclusion: We may suggest that dyslexic subjects might suffer from both magnocellular and parvocellular deficits. Moreover, our results show partial impairment of the koniocellular pathway. Thus, dyslexia might be associated with deficits in all three visual pathways.

  9. Prostaglandin E2 promotes intestinal repair through an adaptive cellular response of the epithelium.

    Science.gov (United States)

    Miyoshi, Hiroyuki; VanDussen, Kelli L; Malvin, Nicole P; Ryu, Stacy H; Wang, Yi; Sonnek, Naomi M; Lai, Chin-Wen; Stappenbeck, Thaddeus S

    2017-01-04

    Adaptive cellular responses are often required during wound repair. Following disruption of the intestinal epithelium, wound-associated epithelial (WAE) cells form the initial barrier over the wound. Our goal was to determine the critical factor that promotes WAE cell differentiation. Using an adaptation of our in vitro primary epithelial cell culture system, we found that prostaglandin E2 (PGE2) signaling through one of its receptors, Ptger4, was sufficient to drive a differentiation state morphologically and transcriptionally similar to in vivo WAE cells. WAE cell differentiation was a permanent state and dominant over enterocyte differentiation in plasticity experiments. WAE cell differentiation was triggered by nuclear β-catenin signaling independent of canonical Wnt signaling. Creation of WAE cells via the PGE2-Ptger4 pathway was required in vivo, as mice with loss of Ptger4 in the intestinal epithelium did not produce WAE cells and exhibited impaired wound repair. Our results demonstrate a mechanism by which WAE cells are formed by PGE2 and suggest a process of adaptive cellular reprogramming of the intestinal epithelium that occurs to ensure proper repair to injury. © 2016 The Authors.

  10. Mechanisms of impaired gallbladder contractile response in chronic acalculous cholecystitis.

    Science.gov (United States)

    Merg, Anders R; Kalinowski, Scott E; Hinkhouse, Marilyn M; Mitros, Frank A; Ephgrave, Kimberly S; Cullen, Joseph J

    2002-01-01

    The mechanisms involved in the impaired gallbladder contractile response in chronic acalculous cholecystitis are unknown. To determine the mechanisms that may lead to impaired gallbladder emptying in chronic acalculous cholecystitis, gallbladder specimens removed during hepatic resection (controls) and after cholecystectomy for chronic acalculous cholecystitis were attached to force transducers and placed in tissue baths with oxygenated Krebs solution. Electrical field stimulation (EFS) (1 to 10 Hz, 0.1 msec, 70 V) or the contractile agonists, CCK-8 (10(-9) to 10(-5)) or K(+) (80 mmol/L), were placed separately in the tissue baths and changes in tension were determined. Patients with chronic acalculous cholecystitis had a mean gallbladder ejection fraction of 12% +/- 4%. Pathologic examination of all gallbladders removed for chronic acalculous cholecystitis revealed chronic cholecystitis. Spontaneous contractile activity was present in gallbladder strips in 83% of control specimens but only 29% of gallbladder strips from patients with chronic acalculous cholecystitis (P < 0.05 vs. controls). CCK-8 contractions were decreased by 54% and EFS-stimulated contractions were decreased by 50% in the presence of chronic acalculous cholecystitis (P < 0.05 vs. controls). K(+)-induced contractions were similar between control and chronic acalculous cholecystitis gallbladder strips. The impaired gallbladder emptying in chronic acalculous cholecystitis appears to be due to diminished spontaneous contractile activity and decreased contractile responsiveness to both CCK and EFS.

  11. Pramipexole Impairs Stimulus-Response Learning in Healthy Young Adults.

    Science.gov (United States)

    Gallant, Haley; Vo, Andrew; Seergobin, Ken N; MacDonald, Penny A

    2016-01-01

    Dopaminergic therapy has paradoxical effects on cognition in Parkinson's disease (PD) patients, with some functions worsened and others improved. The dopamine overdose hypothesis is proposed as an explanation for these opposing effects of medication taking into account the varying levels of dopamine within different brain regions in PD. The detrimental effects of medication on cognition have been attributed to exogenous dopamine overdose in brain regions with spared dopamine levels in PD. It has been demonstrated that learning is most commonly worsened by dopaminergic medication. The current study aimed to investigate whether the medication-related learning impairment exhibited in PD patients is due to a main effect of medication by evaluating the dopamine overdose hypothesis in healthy young adults. Using a randomized, double-blind, placebo-controlled design, 40 healthy young undergraduate students completed a stimulus-response learning task. Half of the participants were treated with 0.5 mg of pramipexole, a dopamine agonist, whereas the other half were treated with a placebo. We found that stimulus-response learning was significantly impaired in participants on pramipexole relative to placebo controls. These findings are consistent with the dopamine overdose hypothesis and suggest that dopaminergic medication impairs learning independent of PD pathology. Our results have important clinical implications for conditions treated with pramipexole, particularly PD, restless leg syndrome, some forms of dystonia, and potentially depression.

  12. Gain of cellular adaptation due to prolonged p53 impairment leads to functional switchover from p53 to p73 during DNA damage in acute myeloid leukemia cells.

    Science.gov (United States)

    Chakraborty, Juni; Banerjee, Shuvomoy; Ray, Pallab; Hossain, Dewan Md Sakib; Bhattacharyya, Sankar; Adhikary, Arghya; Chattopadhyay, Sreya; Das, Tanya; Sa, Gaurisankar

    2010-10-22

    Tumor suppressor p53 plays the central role in regulating apoptosis in response to genotoxic stress. From an evolutionary perspective, the activity of p53 has to be backed up by other protein(s) in case of any functional impairment of this protein, to trigger DNA damage-induced apoptosis in cancer cells. We adopted multiple experimental approaches to demonstrate that in p53-impaired cancer cells, DNA damage caused accumulation of p53 paralogue p73 via Chk-1 that strongly impacted Bax expression and p53-independent apoptosis. On the contrary, when p53 function was restored by ectopic expression, Chk-2 induced p53 accumulation that in turn overshadowed p73 activity, suggesting an antagonistic interaction between p53 family members. To understand such interaction better, p53-expressing cells were impaired differentially for p53 activity. In wild-type p53-expressing cancer cells that were silenced for p53 for several generations, p73 was activated, whereas no such trend was observed when p53 was transiently silenced. Prolonged p53 interference, even in functional p53 settings, therefore, leads to the "gain of cellular adaptation" in a way that alters the cellular microenvironment in favor of p73 activation by altering p73-regulatory proteins, e.g. Chk1 activation and dominant negative p73 down-regulation. These findings not only unveil a hitherto unexplained mechanism underlying the functional switchover from p53 to p73, but also validate p73 as a promising and potential target for cancer therapy in the absence of functional p53.

  13. Impaired autonomic responses to emotional stimuli in autoimmune limbic encephalitis

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    Olga eSchröder

    2015-11-01

    Full Text Available Limbic encephalitis (LE is an autoimmune-mediated disorder that affects structures of the limbic system, in particular the amygdala. The amygdala constitutes a brain area substantial for processing of emotional, especially fear-related signals. The amygdala is also involved in neuroendocrine and autonomic functions, including skin conductance responses (SCRs to emotionally arousing stimuli. This study investigates behavioral and autonomic responses to discrete emotion-evoking and neutral film clips in a patient suffering from LE associated with contactin-associated protein-2 (CASPR2-antibodies as compared to a healthy control group. Results show a lack of SCRs in the patient while watching the film clips, with significant differences compared to healthy controls in the case of fear-inducing videos. There was no comparable impairment in behavioral data (emotion report, valence and arousal ratings. The results point to a defective modulation of sympathetic responses during emotional stimulation in patients with LE, probably due to impaired functioning of the amygdala.

  14. Treatment of Glucocorticoids Inhibited Early Immune Responses and Impaired Cardiac Repair in Adult Zebrafish.

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    Wei-Chang Huang

    Full Text Available Myocardial injury, such as myocardial infarction (MI, can lead to drastic heart damage. Zebrafish have the extraordinary ability to regenerate their heart after a severe injury. Upon ventricle resection, fibrin clots seal the wound and serve as a matrix for recruiting myeloid-derived phagocytes. Accumulated neutrophils and macrophages not only reduce the risk of infection but also secrete cytokines and growth factors to promote tissue repair. However, the underlying cellular and molecular mechanisms for how immune responses are regulated during the early stages of cardiac repair are still unclear. We investigated the role and programming of early immune responses during zebrafish heart regeneration. We found that zebrafish treated with an anti-inflammatory glucocorticoid had significantly reduced heart regenerative capacities, consistent with findings in other higher vertebrates. Moreover, inhibiting the inflammatory response led to excessive collagen deposition. A microarray approach was used to assess the differential expression profiles between zebrafish hearts with normal or impaired healing. Combining cytokine profiling and immune-staining, our data revealed that impaired heart regeneration could be due to reduced phagocyte recruitment, leading to diminished angiogenesis and cell proliferation post-cardiac injury. Despite their robust regenerative ability, our study revealed that glucocorticoid treatment could effectively hinder cardiac repair in adult zebrafish by interfering with the inflammatory response. Our findings may help to clarify the initiation of cardiac repair, which could be used to develop a therapeutic intervention that may enhance cardiac repair in humans to compensate for the loss of cardiomyocytes after an MI.

  15. Transaldolase inhibition impairs mitochondrial respiration and induces a starvation-like longevity response in Caenorhabditis elegans.

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    Christopher F Bennett

    2017-03-01

    Full Text Available Mitochondrial dysfunction can increase oxidative stress and extend lifespan in Caenorhabditis elegans. Homeostatic mechanisms exist to cope with disruptions to mitochondrial function that promote cellular health and organismal longevity. Previously, we determined that decreased expression of the cytosolic pentose phosphate pathway (PPP enzyme transaldolase activates the mitochondrial unfolded protein response (UPRmt and extends lifespan. Here we report that transaldolase (tald-1 deficiency impairs mitochondrial function in vivo, as evidenced by altered mitochondrial morphology, decreased respiration, and increased cellular H2O2 levels. Lifespan extension from knockdown of tald-1 is associated with an oxidative stress response involving p38 and c-Jun N-terminal kinase (JNK MAPKs and a starvation-like response regulated by the transcription factor EB (TFEB homolog HLH-30. The latter response promotes autophagy and increases expression of the flavin-containing monooxygenase 2 (fmo-2. We conclude that cytosolic redox established through the PPP is a key regulator of mitochondrial function and defines a new mechanism for mitochondrial regulation of longevity.

  16. Impaired Memory Retrieval Correlates with Individual Differences in Cortisol Response but Not Autonomic Response

    Science.gov (United States)

    Tranel, Daniel; Adolphs, Ralph; Buchanan, Tony W.

    2006-01-01

    Stress can enhance or impair memory performance. Both cortisol release and sympathetic nervous system responses have been implicated in these differential effects. Here we investigated how memory retrieval might be affected by stress-induced cortisol release, independently of sympathetic nervous system stress responses. Thirty-two healthy…

  17. Effect of Gold Nanorod Surface Chemistry on Cellular Response

    Science.gov (United States)

    2011-03-15

    Recombi - nation DNA Repair Network for Targeted Cancer Therapy. World J. Clin. Oncol. 2011, 2, 73–79. 36. Higashi, H.; Vallb€ohmer, D.; Warnecke-Eberz, U...cellular morphology, mitochondrial function, mitochondrial membrane potential (MMP), intracellular calcium levels, DNA damage-related gene expression, and of...observed in the MMP and Ca++ levels, up or down regulation of DNA damage related gene expression suggested a differential cell death mechanism based on

  18. Marine molluscs in environmental monitoring. I. Cellular and molecular responses

    Science.gov (United States)

    Bresler, Vladimir; Abelson, Avigdor; Fishelson, Lev; Feldstein, Tamar; Rosenfeld, Michael; Mokady, Ofer

    2003-10-01

    The study reported here is part of an ongoing effort to establish sensitive and reliable biomonitoring markers for probing the coastal marine environment. Here, we report comparative measurements of a range of histological, cellular and sub-cellular parameters in molluscs sampled in polluted and reference sites along the Mediterranean coast of Israel and in the northern tip of the Gulf of Aqaba, Red Sea. Available species enabled an examination of conditions in two environmental 'compartments': benthic (Donax trunculus) and intertidal (Brachidontes pharaonis, Patella caerulea) in the Mediterranean; pelagic (Pteria aegyptia) and intertidal (Cellana rota) in the Red Sea. The methodology used provides rapid results by combining specialized fluorescent probes and contact microscopy, by which all parameters are measured in unprocessed animal tissue. The research focused on three interconnected levels. First, antixenobiotic defence mechanisms aimed at keeping hazardous agents outside the cell. Paracellular permeability was 70-100% higher in polluted sites, and membrane pumps (MXRtr and SATOA) activity was up to 65% higher in polluted compared to reference sites. Second, intracellular defence mechanisms that act to minimize potential damage by agents having penetrated the first line of defence. Metallothionein expression and EROD activity were 160-520% higher in polluted sites, and lysosomal functional activity (as measured by neutral red accumulation) was 25-50% lower. Third, damage caused by agents not sufficiently eliminated by the above mechanisms (e.g. single-stranded DNA breaks, chromosome damage and other pathological alterations). At this level, the most striking differences were observed in the rate of micronuclei formation and DNA breaks (up to 150% and 400% higher in polluted sites, respectively). The different mollusc species used feature very similar trends between polluted and reference sites in all measured parameters. Concentrating on relatively basic

  19. p53-Mediated Cellular Response to DNA Damage in Cells with Replicative Hepatitis B Virus

    Science.gov (United States)

    Puisieux, Alain; Ji, Jingwei; Guillot, Celine; Legros, Yann; Soussi, Thierry; Isselbacher, Kurt; Ozturk, Mehmet

    1995-02-01

    Wild-type p53 acts as a tumor suppressor gene by protecting cells from deleterious effects of genotoxic agents through the induction of a G_1/S arrest or apoptosis as a response to DNA damage. Transforming proteins of several oncogenic DNA viruses inactivate tumor suppressor activity of p53 by blocking this cellular response. To test whether hepatitis B virus displays a similar effect, we studied the p53-mediated cellular response to DNA damage in 2215 hepatoma cells with replicative hepatitis B virus. We demonstrate that hepatitis B virus replication does not interfere with known cellular functions of p53 protein.

  20. Functional connectivity correlates of response inhibition impairment in anorexia nervosa.

    Science.gov (United States)

    Collantoni, Enrico; Michelon, Silvia; Tenconi, Elena; Degortes, Daniela; Titton, Francesca; Manara, Renzo; Clementi, Maurizio; Pinato, Claudia; Forzan, Monica; Cassina, Matteo; Santonastaso, Paolo; Favaro, Angela

    2016-01-30

    Anorexia nervosa (AN) is a disorder characterized by high levels of cognitive control and behavioral perseveration. The present study aims at exploring inhibitory control abilities and their functional connectivity correlates in patients with AN. Inhibitory control - an executive function that allows the realization of adaptive behavior according to environmental contingencies - has been assessed by means of the Stop-Signal paradigm. The study involved 155 patients with lifetime AN and 102 healthy women. A subsample underwent resting-state functional magnetic resonance imaging and was genotyped for COMT and 5-HTTLPR polymorphisms. AN patients showed an impaired response inhibition and a disruption of the functional connectivity of the ventral attention circuit, a neural network implicated in behavioral response when a stimulus occurs unexpected. The 5-HTTLPR genotype appears to significantly interact with the functional connectivity of ventral attention network in explaining task performance in both patients and controls, suggesting a role of the serotoninergic system in mechanisms of response selection. The disruption of the ventral attention network in patients with AN suggests lower efficiency of bottom-up signal filtering, which might be involved in difficulties to adapt behavioral responses to environmental needs. Our findings deserve further research to confirm their scientific and therapeutic implications.

  1. Cellular Responses to the Metal-Binding Properties of Metformin

    Science.gov (United States)

    Logie, Lisa; Harthill, Jean; Patel, Kashyap; Bacon, Sandra; Hamilton, D. Lee; Macrae, Katherine; McDougall, Gordon; Wang, Huan-Huan; Xue, Lin; Jiang, Hua; Sakamoto, Kei; Prescott, Alan R.; Rena, Graham

    2012-01-01

    In recent decades, the antihyperglycemic biguanide metformin has been used extensively in the treatment of type 2 diabetes, despite continuing uncertainty over its direct target. In this article, using two independent approaches, we demonstrate that cellular actions of metformin are disrupted by interference with its metal-binding properties, which have been known for over a century but little studied by biologists. We demonstrate that copper sequestration opposes known actions of metformin not only on AMP-activated protein kinase (AMPK)-dependent signaling, but also on S6 protein phosphorylation. Biguanide/metal interactions are stabilized by extensive π-electron delocalization and by investigating analogs of metformin; we provide evidence that this intrinsic property enables biguanides to regulate AMPK, glucose production, gluconeogenic gene expression, mitochondrial respiration, and mitochondrial copper binding. In contrast, regulation of S6 phosphorylation is prevented only by direct modification of the metal-liganding groups of the biguanide structure, supporting recent data that AMPK and S6 phosphorylation are regulated independently by biguanides. Additional studies with pioglitazone suggest that mitochondrial copper is targeted by both of these clinically important drugs. Together, these results suggest that cellular effects of biguanides depend on their metal-binding properties. This link may illuminate a better understanding of the molecular mechanisms enabling antihyperglycemic drug action. PMID:22492524

  2. Evolutionary principles underlying structure and response dynamics of cellular networks.

    Science.gov (United States)

    Steinacher, Arno; Soyer, Orkun S

    2012-01-01

    The network view in systems biology, in conjunction with the continuing development of experimental technologies, is providing us with the key structural and dynamical features of both cell-wide and pathway-level regulatory, signaling and metabolic systems. These include for example modularity and presence of hub proteins at the structural level and ultrasensitivity and feedback control at the level of dynamics. The uncovering of such features, and the seeming commonality of some of them, makes many systems biologists believe that these could represent design principles that underpin cellular systems across organisms. Here, we argue that such claims on any observed feature requires an understanding of how it has emerged in evolution and how it can shape subsequent evolution. We review recent and past studies that aim to achieve such evolutionary understanding for observed features of cellular networks. We argue that this evolutionary framework could lead to deciphering evolutionary origin and relevance of proposed design principles, thereby allowing to predict their presence or absence in an organism based on its environment and biochemistry and their effect on its future evolution.

  3. Mutations in Bruton's tyrosine kinase impair IgA responses.

    Science.gov (United States)

    Mitsuiki, Noriko; Yang, Xi; Bartol, Sophinus J W; Grosserichter-Wagener, Christina; Kosaka, Yoshiyuki; Takada, Hidetoshi; Imai, Kohsuke; Kanegane, Hirokazu; Mizutani, Shuki; van der Burg, Mirjam; van Zelm, Menno C; Ohara, Osamu; Morio, Tomohiro

    2015-03-01

    X-linked agammaglobulinemia (XLA) is a primary immunodeficiency caused by mutations in Bruton's tyrosine kinase (BTK), and is characterized by markedly decreased numbers of blood B cells and an absence of all immunoglobulin isotypes. We performed whole exome sequencing in a male pediatric patient with dysgammaglobulinemia with IgA deficiency. Genetic analysis revealed a BTK missense mutation (Thr316Ala). To investigate whether a BTK mutation underlay this antibody deficiency with marked decrease of IgA in this patient, we performed functional analyses of B cells and phagocytes, and molecular analyses of somatic hypermutation and class switch recombination. The BTK missense mutation resulted in B cells with reduced BTK and high IgM expression. Equal proportions of CD19(low) and CD19(normal) fractions were observed, and both included naïve and memory B cells. Calcium influx and phospholipase Cγ2 phosphorylation upon IgM stimulation were marginally impaired in CD19(low), but not in CD19(+) B cells. Similar to XLA patients, IgA transcripts showed low SHM levels, whereas IgG transcripts were hardly affected. Our analyses suggest that the BTK mutation likely underlies the disease in this case, and that hypomorphic BTK mutations can result in normal circulating B cell numbers, but specifically impair IgA responses.

  4. Impaired macrophage autophagy increases the immune response in obese mice by promoting proinflammatory macrophage polarization.

    Science.gov (United States)

    Liu, Kun; Zhao, Enpeng; Ilyas, Ghulam; Lalazar, Gadi; Lin, Yu; Haseeb, Muhammad; Tanaka, Kathryn E; Czaja, Mark J

    2015-01-01

    Recent evidence that excessive lipid accumulation can decrease cellular levels of autophagy and that autophagy regulates immune responsiveness suggested that impaired macrophage autophagy may promote the increased innate immune activation that underlies obesity. Primary bone marrow-derived macrophages (BMDM) and peritoneal macrophages from high-fat diet (HFD)-fed mice had decreased levels of autophagic flux indicating a generalized impairment of macrophage autophagy in obese mice. To assess the effects of decreased macrophage autophagy on inflammation, mice with a Lyz2-Cre-mediated knockout of Atg5 in macrophages were fed a HFD and treated with low-dose lipopolysaccharide (LPS). Knockout mice developed systemic and hepatic inflammation with HFD feeding and LPS. This effect was liver specific as knockout mice did not have increased adipose tissue inflammation. The mechanism by which the loss of autophagy promoted inflammation was through the regulation of macrophage polarization. BMDM and Kupffer cells from knockout mice exhibited abnormalities in polarization with both increased proinflammatory M1 and decreased anti-inflammatory M2 polarization as determined by measures of genes and proteins. The heightened hepatic inflammatory response in HFD-fed, LPS-treated knockout mice led to liver injury without affecting steatosis. These findings demonstrate that autophagy has a critical regulatory function in macrophage polarization that downregulates inflammation. Defects in macrophage autophagy may underlie inflammatory disease states such as the decrease in macrophage autophagy with obesity that leads to hepatic inflammation and the progression to liver injury.

  5. Development of second generation peptides modulating cellular adiponectin receptor responses

    Science.gov (United States)

    Otvos, Laszlo; Knappe, Daniel; Hoffmann, Ralf; Kovalszky, Ilona; Olah, Julia; Hewitson, Tim; Stawikowska, Roma; Stawikowski, Maciej; Cudic, Predrag; Lin, Feng; Wade, John; Surmacz, Eva; Lovas, Sandor

    2014-10-01

    The adipose tissue participates in the regulation of energy homeostasis as an important endocrine organ that secretes a number of biologically active adipokines, including adiponectin. Recently we developed and characterized a first-in-class peptide-based adiponectin receptor agonist by using in vitro and in vivo models of glioblastoma and breast cancer (BC). In the current study, we further explored the effects of peptide ADP355 in additional cellular models and found that ADP355 inhibited chronic myeloid leukemia (CML) cell proliferation and renal myofibroblast differentiation with mid-nanomolar IC50 values. According to molecular modeling calculations, ADP355 was remarkably flexible in the global minimum with a turn present in the middle of the peptide. Considering these structural features of ADP355 and the fact that adiponectin normally circulates as multimeric complexes, we developed and tested the activity of a linear branched dimer (ADP399). The dimer exhibited approximately 20-fold improved cellular activity inhibiting K562 CML and MCF-7 cell growth with high pM - low nM relative IC50 values. Biodistribution studies suggested superior tissue dissemination of both peptides after subcutaneous administration relative to intraperitoneal inoculation. After screening of a 397-member adiponectin active site library, a novel octapeptide (ADP400) was designed that counteracted 10-1000 nM ADP355- and ADP399-mediated effects on CML and BC cell growth at nanomolar concentrations. ADP400 induced mitogenic effects in MCF-7 BC cells perhaps due to antagonizing endogenous adiponectin actions or acting as an inverse agonist. While the linear dimer agonist ADP399 meets pharmacological criteria of a contemporary peptide drug lead, the peptide showing antagonist activity (ADP400) at similar concentrations will be an important target validation tool to study adiponectin functions.

  6. Development of second generation peptides modulating cellular adiponectin receptor responses

    Directory of Open Access Journals (Sweden)

    Laszlo eOtvos

    2014-10-01

    Full Text Available The adipose tissue participates in the regulation of energy homeostasis as an important endocrine organ that secretes a number of biologically active adipokines, including adiponectin. Recently we developed and characterized a first-in-class peptide-based adiponectin receptor agonist by using in vitro and in vivo models of glioblastoma and breast cancer (BC. In the current study, we further explored the effects of peptide ADP355 in additional cellular models and found that ADP355 inhibited chronic myeloid leukemia (CML cell proliferation and renal myofibroblast differentiation with mid-nanomolar IC50 values. According to molecular modeling calculations, ADP355 was remarkably flexible in the global minimum with a turn present in the middle of the peptide. Considering these structural features of ADP355 and the fact that adiponectin normally circulates as multimeric complexes, we developed and tested the activity of a linear branched dimer (ADP399. The dimer exhibited approximately 20-fold improved cellular activity inhibiting K562 CML and MCF-7 cell growth with high pM - low nM relative IC50 values. Biodistribution studies suggested superior tissue dissemination of both peptides after subcutaneous administration relative to intraperitoneal inoculation. After screening of a 397-member adiponectin active site library, a novel octapeptide (ADP400 was designed that counteracted 10-1000 nM ADP355- and ADP399-mediated effects on CML and BC cell growth at nanomolar concentrations. ADP400 induced mitogenic effects in MCF-7 BC cells perhaps due to antagonizing endogenous adiponectin actions or acting as an inverse agonist. While the linear dimer agonist ADP399 meets pharmacological criteria of a contemporary peptide drug lead, the peptide showing antagonist activity (ADP400 at similar concentrations will be an important target validation tool to study adiponectin functions.

  7. The Inhibitor of Apoptosis (IAPs) in Adaptive Response to Cellular Stress.

    Science.gov (United States)

    Marivin, Arthur; Berthelet, Jean; Plenchette, Stéphanie; Dubrez, Laurence

    2012-10-10

    Cells are constantly exposed to endogenous and exogenous cellular injuries. They cope with stressful stimuli by adapting their metabolism and activating various "guardian molecules." These pro-survival factors protect essential cell constituents, prevent cell death, and possibly repair cellular damages. The Inhibitor of Apoptosis (IAPs) proteins display both anti-apoptotic and pro-survival properties and their expression can be induced by a variety of cellular stress such as hypoxia, endoplasmic reticular stress and DNA damage. Thus, IAPs can confer tolerance to cellular stress. This review presents the anti-apoptotic and survival functions of IAPs and their role in the adaptive response to cellular stress. The involvement of IAPs in human physiology and diseases in connection with a breakdown of cellular homeostasis will be discussed.

  8. Acute, regional inflammatory response after traumatic brain injury: Implications for cellular therapy

    OpenAIRE

    Harting, Matthew T.; jimenez, fernando; Adams, Sasha D.; Mercer, David W.; Cox, Charles S.

    2008-01-01

    While cellular therapy has shown promise in the management of traumatic brain injury (TBI), microenvironment interactions between the intracerebral milieu and therapeutic stem cells are poorly understood. We sought to characterize the acute, regional inflammatory response after TBI.

  9. A new cellular stress response that triggers centriolar satellite reorganization and ciliogenesis

    DEFF Research Database (Denmark)

    Villumsen, Bine H; Danielsen, Jannie R; Povlsen, Lou;

    2013-01-01

    Centriolar satellites are small, granular structures that cluster around centrosomes, but whose biological function and regulation are poorly understood. We show that centriolar satellites undergo striking reorganization in response to cellular stresses such as UV radiation, heat shock...

  10. SaeRS Is Responsive to Cellular Respiratory Status and Regulates Fermentative Biofilm Formation in Staphylococcus aureus.

    Science.gov (United States)

    Mashruwala, Ameya A; Gries, Casey M; Scherr, Tyler D; Kielian, Tammy; Boyd, Jeffrey M

    2017-08-01

    Biofilms are multicellular communities of microorganisms living as a quorum rather than as individual cells. The bacterial human pathogen Staphylococcus aureus uses oxygen as a terminal electron acceptor during respiration. Infected human tissues are hypoxic or anoxic. We recently reported that impaired respiration elicits a programmed cell lysis (PCL) phenomenon in S. aureus leading to the release of cellular polymers that are utilized to form biofilms. PCL is dependent upon the AtlA murein hydrolase and is regulated, in part, by the SrrAB two-component regulatory system (TCRS). In the current study, we report that the SaeRS TCRS also governs fermentative biofilm formation by positively influencing AtlA activity. The SaeRS-modulated factor fibronectin-binding protein A (FnBPA) also contributed to the fermentative biofilm formation phenotype. SaeRS-dependent biofilm formation occurred in response to changes in cellular respiratory status. Genetic evidence presented suggests that a high cellular titer of phosphorylated SaeR is required for biofilm formation. Epistasis analyses found that SaeRS and SrrAB influence biofilm formation independently of one another. Analyses using a mouse model of orthopedic implant-associated biofilm formation found that both SaeRS and SrrAB govern host colonization. Of these two TCRSs, SrrAB was the dominant system driving biofilm formation in vivo We propose a model wherein impaired cellular respiration stimulates SaeRS via an as yet undefined signal molecule(s), resulting in increasing expression of AtlA and FnBPA and biofilm formation. Copyright © 2017 American Society for Microbiology.

  11. Impaired memory retrieval correlates with individual differences in cortisol response but not autonomic response

    OpenAIRE

    Buchanan, Tony W.; Tranel, Daniel; Adolphs, Ralph

    2006-01-01

    Stress can enhance or impair memory performance. Both cortisol release and sympathetic nervous system responses have been implicated in these differential effects. Here we investigated how memory retrieval might be affected by stress-induced cortisol release, independently of sympathetic nervous system stress responses. Thirty-two healthy participants (16 women) learned emotionally arousing and neutral words. One hour later, half of the participants underwent a stressor (cold pressor test) an...

  12. Systems microscopy to unravel cellular stress response signalling in drug induced liver injury

    NARCIS (Netherlands)

    Wink, Steven

    2015-01-01

    Toxicological insults are met by cellular adaptive stress response pathway activation. We find that activation of adaptive stress responses occur well before the typical ultimate outcome of chemical cell injury. To increase our understanding of chemically-induced adaptive stress response pathway act

  13. Telomere shortening impairs regeneration of the olfactory epithelium in response to injury but not under homeostatic conditions.

    Directory of Open Access Journals (Sweden)

    Masami Watabe-Rudolph

    Full Text Available Atrophy of the olfactory epithelium (OE associated with impaired olfaction and dry nose represents one of the most common phenotypes of human aging. Impairment in regeneration of a functional olfactory epithelium can also occur in response to injury due to infection or nasal surgery. These complications occur more frequently in aged patients. Although age is the most unifying risk factor for atrophic changes and functional decline of the olfactory epithelium, little is known about molecular mechanisms that could influence maintenance and repair of the olfactory epithelium. Here, we analyzed the influence of telomere shortening (a basic mechanism of cellular aging on homeostasis and regenerative reserve in response to chemical induced injury of the OE in late generation telomere knockout mice (G3 mTerc(-/- with short telomeres compared to wild type mice (mTerc(+/+ with long telomeres. The study revealed no significant influence of telomere shortening on homeostatic maintenance of the OE during mouse aging. In contrast, the regenerative response to chemical induced injury of the OE was significantly impaired in G3 mTerc(-/- mice compared to mTerc(+/+ mice. Seven days after chemical induced damage, G3 mTerc(-/- mice exhibited significantly enlarged areas of persisting atrophy compared to mTerc(+/+ mice (p = 0.031. Telomere dysfunction was associated with impairments in cell proliferation in the regenerating epithelium. Deletion of the cell cycle inhibitor, Cdkn1a (p21 rescued defects in OE regeneration in telomere dysfunctional mice. Together, these data indicate that telomere shortening impairs the regenerative capacity of the OE by impairing cell cycle progression in a p21-dependent manner. These findings could be relevant for the impairment in OE function in elderly people.

  14. Iron Deficiency Impairs Intra-Hepatic Lymphocyte Mediated Immune Response.

    Directory of Open Access Journals (Sweden)

    Eliano Bonaccorsi-Riani

    Full Text Available Hepatic expression of iron homeostasis genes and serum iron parameters predict the success of immunosuppression withdrawal following clinical liver transplantation, a phenomenon known as spontaneous operational tolerance. In experimental animal models, spontaneous liver allograft tolerance is established through a process that requires intra-hepatic lymphocyte activation and deletion. Our aim was to determine if changes in systemic iron status regulate intra-hepatic lymphocyte responses. We used a murine model of lymphocyte-mediated acute liver inflammation induced by Concanavalin A (ConA injection employing mice fed with an iron-deficient (IrDef or an iron-balanced diet (IrRepl. While the mild iron deficiency induced by the IrDef diet did not significantly modify the steady state immune cell repertoire and systemic cytokine levels, it significantly dampened inflammatory liver damage after ConA challenge. These findings were associated with a marked decrease in T cell and NKT cell activation following ConA injection in IrDef mice. The decreased liver injury observed in IrDef mice was independent from changes in the gut microflora, and was replicated employing an iron specific chelator that did not modify intra-hepatic hepcidin secretion. Furthermore, low-dose iron chelation markedly impaired the activation of isolated T cells in vitro. All together, these results suggest that small changes in iron homeostasis can have a major effect in the regulation of intra-hepatic lymphocyte mediated responses.

  15. Effect of Compound Glycyrrhizin Injection on Liver Function and Cellular Immunity of Children with Infectious Mononucleosis Complicated Liver Impairment

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective: To investigate the effects of Compound Glycyrrhizin Injection (CGI) on liver function and cellular immunity of children with infectious mononucleosis complicated liver impairment (IM-LI) and to explore its clinical therapeutic effect. Methods: Forty-two patients with IM-LI were randomly assigned, according to the randomizing number table, to two groups, 20 in the control group and 22 in the treated group.All the patients were treated with conventional treatment, but to those in the treated group, CGI was given additionally once a day, at the dosage of 10 ml for children aged below 2 years, 20 ml for 2-4 years old, 30 ml for 5-7 years old and 40 ml for 8- 12 years old, in 100-200 ml of 5% glucose solution by intravenous dripping. The treatment lasted for 2 weeks. T lymphocyte subsets and serum levels of alanine transaminase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBil) were detected before and after treatment. Besides, a normal control group consisting of 20 healthy children was also set up. Results: Baseline of the percentage of CD3 + , CD8 + lymphocyte and serum levels of ALT, AST, TBiL in the children with IM-LI were markedly higher, while the percentage of CD4 + lymphocyte and the CD4 +/CD8 + ratio was markedly lower in IM-LI children as compared with the corresponding indices in the healthy children ( P<0.01 ). These indices were improved after treatment in both groups of patients, but the improvement in the treated group was better than that in the control group (P<0.01). Conclusion: Cellular immunity dysfunction often occurs in patients with IM-LI, and CGI treatment can not only obviously promote the recovery of liver function, but also regulate the immune function in organism.

  16. The cellular response to curvature-induced stress

    Science.gov (United States)

    Biton, Y. Y.; Safran, S. A.

    2009-12-01

    We present a theoretical model to explain recent observations of the orientational response of cells to unidirectional curvature. Experiments show that some cell types when plated on a rigid cylindrical surface tend to reorient their shape and stress fibers along the axis of the cylinder, while others align their stress fibers perpendicular to that axis. Our model focuses on the competition of the shear stress—that results from cell adhesion and active contractility—and the anisotropic bending stiffness of the stress fibers. We predict the cell orientation angle that results from the balance of these two forces in a mechanical equilibrium. The conditions under which the different experimental observations can be obtained are discussed in terms of the theory.

  17. Cellular Responses to Cisplatin-Induced DNA Damage

    Directory of Open Access Journals (Sweden)

    Alakananda Basu

    2010-01-01

    Full Text Available Cisplatin is one of the most effective anticancer agents widely used in the treatment of solid tumors. It is generally considered as a cytotoxic drug which kills cancer cells by damaging DNA and inhibiting DNA synthesis. How cells respond to cisplatin-induced DNA damage plays a critical role in deciding cisplatin sensitivity. Cisplatin-induced DNA damage activates various signaling pathways to prevent or promote cell death. This paper summarizes our current understandings regarding the mechanisms by which cisplatin induces cell death and the bases of cisplatin resistance. We have discussed various steps, including the entry of cisplatin inside cells, DNA repair, drug detoxification, DNA damage response, and regulation of cisplatin-induced apoptosis by protein kinases. An understanding of how various signaling pathways regulate cisplatin-induced cell death should aid in the development of more effective therapeutic strategies for the treatment of cancer.

  18. The cellular inflammatory response in human spinal cords after injury.

    Science.gov (United States)

    Fleming, Jennifer C; Norenberg, Michael D; Ramsay, David A; Dekaban, Gregory A; Marcillo, Alexander E; Saenz, Alvaro D; Pasquale-Styles, Melissa; Dietrich, W Dalton; Weaver, Lynne C

    2006-12-01

    Spinal cord injury (SCI) provokes an inflammatory response that generates substantial secondary damage within the cord but also may contribute to its repair. Anti-inflammatory treatment of human SCI and its timing must be based on knowledge of the types of cells participating in the inflammatory response, the time after injury when they appear and then decrease in number, and the nature of their actions. Using post-mortem spinal cords, we evaluated the time course and distribution of pathological change, infiltrating neutrophils, monocytes/macrophages and lymphocytes, and microglial activation in injured spinal cords from patients who were 'dead at the scene' or who survived for intervals up to 1 year after SCI. SCI caused zones of pathological change, including areas of inflammation and necrosis in the acute cases, and cystic cavities with longer survival (Zone 1), mantles of less severe change, including axonal swellings, inflammation and Wallerian degeneration (Zone 2) and histologically intact areas (Zone 3). Zone 1 areas increased in size with time after injury whereas the overall injury (size of the Zones 1 and 2 combined) remained relatively constant from the time (1-3 days) when damage was first visible. The distribution of inflammatory cells correlated well with the location of Zone 1, and sometimes of Zone 2. Neutrophils, visualized by their expression of human neutrophil alpha-defensins (defensin), entered the spinal cord by haemorrhage or extravasation, were most numerous 1-3 days after SCI, and were detectable for up to 10 days after SCI. Significant numbers of activated CD68-immunoreactive ramified microglia and a few monocytes/macrophages were in injured tissue within 1-3 days of SCI. Activated microglia, a few monocytes/macrophages and numerous phagocytic macrophages were present for weeks to months after SCI. A few CD8(+) lymphocytes were in the injured cords throughout the sampling intervals. Expression by the inflammatory cells of the oxidative

  19. Adjuvant activity of peanut, cottonseed and rice oils on cellular and humoral response

    Directory of Open Access Journals (Sweden)

    Erika Freitas

    2013-04-01

    Full Text Available The potentiality of the usage of vegetable oils such as soybean, corn, olive, sesame, murici seed, rapeseed, linseed, rice and cashew nuts as adjuvant of the humoral and cellular immune response has been recently shown. In the present work, besides of evaluating the adjuvant action of peanut, cottonseed and rice oils on humoral and cellular immune responses against ovalbumin (OVA we also evaluated the protective immune response induced by Leishmania antigens. The peanut oil significantly increased the synthesis of anti-ovalbumin antibodies in the primary response, but it did not favor cellular response. Concerning mice immunized with L. amazonensis antigens emulsified with peanut oil exacerbated skin lesions and lymph node parasite load what suggests stimulation of the Th2 immune response and down regulation of Th1 response. The cottonseed oil was shown to have adjuvant effect to the humoral response, stimulating a secondary response and also favored the delayed-type hypersensitivity (DTH response to OVA. The rice oil stimulated a strong DTH reaction to OVA and enhanced the synthesis of antibodies after the third dose. Mice immunized with L. amazonensis antigens emulsified with rice oil or cotton seed oil were protected from developing skin lesions and lymph node parasite load. These results emphasize the interest and importance of the vegetable oils as tools in different procedures of immunization and their differential role in relation to the other adjuvant under usage.

  20. Helicobacter pylori impairs murine dendritic cell responses to infection.

    Directory of Open Access Journals (Sweden)

    Ya-Hui Wang

    Full Text Available BACKGROUND: Helicobacter pylori, a human pathogen associated with chronic gastritis, peptic ulcer and gastric malignancies, is generally viewed as an extracellular microorganism. Here, we show that H. pylori replicates in murine bone marrow derived-dendritic cells (BMDCs within autophagosomes. METHODOLOGY/PRINCIPAL FINDINGS: A 10-fold increase of CFU is found between 2 h and 6 h p.i. in H. pylori-infected BMDCs. Autophagy is induced around the bacterium and participates at late time points of infection for the clearance of intracellular H. pylori. As a consequence of infection, LC3, LAMP1 and MHC class II molecules are retained within the H. pylori-containing vacuoles and export of MHC class II molecules to cell surface is blocked. However, formalin-fixed H. pylori still maintain this inhibitory activity in BMDC derived from wild type mice, but not in from either TLR4 or TLR2-deficient mice, suggesting the involvement of H. pylori-LPS in this process. TNF-alpha, IL-6 and IL-10 expression was also modulated upon infection showing a TLR2-specific dependent IL-10 secretion. No IL-12 was detected favoring the hypothesis of a down modulation of DC functions during H. pylori infection. Furthermore, antigen-specific T cells proliferation was also impaired upon infection. CONCLUSIONS/SIGNIFICANCE: H. pylori can infect and replicate in BMDCs and thereby affects DC-mediated immune responses. The implication of this new finding is discussed for the biological life cycle of H. pylori in the host.

  1. The cellular energization state affects peripheral stalk stability of plant vacuolar H+-ATPase and impairs vacuolar acidification.

    Science.gov (United States)

    Schnitzer, Daniel; Seidel, Thorsten; Sander, Tim; Golldack, Dortje; Dietz, Karl-Josef

    2011-05-01

    The plant vacuolar H(+)-ATPase takes part in acidifying compartments of the endomembrane system including the secretory pathway and the vacuoles. The structural variability of the V-ATPase complex as well as its presence in different compartments and tissues involves multiple isoforms of V-ATPase subunits. Furthermore, a versatile regulation is essential to allow for organelle- and tissue-specific fine tuning. In this study, results from V-ATPase complex disassembly with a chaotropic reagent, immunodetection and in vivo fluorescence resonance energy transfer (FRET) analyses point to a regulatory mechanism in plants, which depends on energization and involves the stability of the peripheral stalks as well. Lowering of cellular ATP by feeding 2-deoxyglucose resulted in structural alterations within the V-ATPase, as monitored by changes in FRET efficiency between subunits VHA-E and VHA-C. Potassium iodide-mediated disassembly revealed a reduced stability of V-ATPase after 2-deoxyglucose treatment of the cells, but neither the complete V(1)-sector nor VHA-C was released from the membrane in response to 2-deoxyglucose treatment, precluding a reversible dissociation mechanism like in yeast. These data suggest the existence of a regulatory mechanism of plant V-ATPase by modification of the peripheral stator structure that is linked to the cellular energization state. This mechanism is distinct from reversible dissociation as reported for the yeast V-ATPase, but might represent an evolutionary precursor of reversible dissociation.

  2. In vivo imaging of C. elegans ASH neurons: cellular response and adaptation to chemical repellents

    OpenAIRE

    Hilliard, Massimo A.; Apicella, Alfonso J.; Kerr, Rex; Suzuki, Hiroshi; Bazzicalupo, Paolo; Schafer, William R

    2004-01-01

    ASH sensory neurons are required in Caenorhabditis elegans for a wide range of avoidance behaviors in response to chemical repellents, high osmotic solutions and nose touch. The ASH neurons are therefore hypothesized to be polymodal nociceptive neurons. To understand the nature of polymodal sensory response and adaptation at the cellular level, we expressed the calcium indicator protein cameleon in ASH and analyzed intracellular Ca2+ responses following stimulation with chemical repellents, o...

  3. Isoniazid suppresses antioxidant response element activities and impairs adipogenesis in mouse and human preadipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yanyan [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); The First Affiliated Hospital, China Medical University, Shenyang 110001 (China); Xue, Peng [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); Key Laboratory of the Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai (China); Hou, Yongyong [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); School of Public Health, China Medical University, Shenyang 110001 (China); Zhang, Hao [Key Laboratory of the Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai (China); Zheng, Hongzhi [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); The First Affiliated Hospital, China Medical University, Shenyang 110001 (China); Zhou, Tong [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); Qu, Weidong [Key Laboratory of the Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai (China); Teng, Weiping [The First Affiliated Hospital, China Medical University, Shenyang 110001 (China); Zhang, Qiang; Andersen, Melvin E. [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); Pi, Jingbo, E-mail: jingbopi@gmail.com [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); School of Public Health, China Medical University, Shenyang 110001 (China)

    2013-12-15

    Transcriptional signaling through the antioxidant response element (ARE), orchestrated by the Nuclear factor E2-related factor 2 (Nrf2), is a major cellular defense mechanism against oxidative or electrophilic stress. Here, we reported that isoniazid (INH), a widely used antitubercular drug, displays a substantial inhibitory property against ARE activities in diverse mouse and human cells. In 3T3-L1 preadipocytes, INH concentration-dependently suppressed the ARE-luciferase reporter activity and mRNA expression of various ARE-dependent antioxidant genes under basal and oxidative stressed conditions. In keeping with our previous findings that Nrf2-ARE plays a critical role in adipogenesis by regulating expression of CCAAT/enhancer-binding protein β (C/EBPβ) and peroxisome proliferator-activated receptor γ (PPARγ), suppression of ARE signaling by INH hampered adipogenic differentiation of 3T3-L1 cells and human adipose-derived stem cells (ADSCs). Following adipogenesis induced by hormonal cocktails, INH-treated 3T3-L1 cells and ADSCs displayed significantly reduced levels of lipid accumulation and attenuated expression of C/EBPα and PPARγ. Time-course studies in 3T3-L1 cells revealed that inhibition of adipogenesis by INH occurred in the early stage of terminal adipogenic differentiation, where reduced expression of C/EBPβ and C/EBPδ was observed. To our knowledge, the present study is the first to demonstrate that INH suppresses ARE signaling and interrupts with the transcriptional network of adipogenesis, leading to impaired adipogenic differentiation. The inhibition of ARE signaling may be a potential underlying mechanism by which INH attenuates cellular antioxidant response contributing to various complications. - Highlights: • Isoniazid suppresses ARE-mediated transcriptional activity. • Isoniazid inhibits adipogenesis in preadipocytes. • Isoniazid suppresses adipogenic gene expression during adipogenesis.

  4. Lymphocyte transformation assay for C neoformans antigen is not reliable for detecting cellular impairment in patients with Neurocryptococcosis

    Directory of Open Access Journals (Sweden)

    Rocha Katya C

    2012-10-01

    Full Text Available Abstract Background Cryptococcus neoformans causes meningitis and disseminated infection in healthy individuals, but more commonly in hosts with defective immune responses. Cell-mediated immunity is an important component of the immune response to a great variety of infections, including yeast infections. We aimed to evaluate a specific lymphocyte transformation assay to Cryptococcus neoformans in order to identify immunodeficiency associated to neurocryptococcosis (NCC as primary cause of the mycosis. Methods Healthy volunteers, poultry growers, and HIV-seronegative patients with neurocryptococcosis were tested for cellular immune response. Cryptococcal meningitis was diagnosed by India ink staining of cerebrospinal fluid and cryptococcal antigen test (Immunomycol-Inc, SP, Brazil. Isolated peripheral blood mononuclear cells were stimulated with C. neoformans antigen, C. albicans antigen, and pokeweed mitogen. The amount of 3H-thymidine incorporated was assessed, and the results were expressed as stimulation index (SI and log SI, sensitivity, specificity, and cut-off value (receiver operating characteristics curve. We applied unpaired Student t tests to compare data and considered significant differences for p Results The lymphotoxin alpha showed a low capacity with all the stimuli for classifying patients as responders and non-responders. Lymphotoxin alpha stimulated by heated-killed antigen from patients with neurocryptococcosis was not affected by TCD4+ cell count, and the intensity of response did not correlate with the clinical evolution of neurocryptococcosis. Conclusion Response to lymphocyte transformation assay should be analyzed based on a normal range and using more than one stimulator. The use of a cut-off value to classify patients with neurocryptococcosis is inadequate. Statistical analysis should be based on the log transformation of SI. A more purified antigen for evaluating specific response to C. neoformans is needed.

  5. Treatment with 1,25-dihydroxyvitamin D3 reduces impairment of human osteoblast functions during cellular aging in culture

    DEFF Research Database (Denmark)

    Kveiborg, Marie; Rattan, Suresh; Clark, Brian F.C.

    2001-01-01

    of alkaline phosphatase (AP: 68%), osteocalcin (OC: 67%), and collagen type I (ColI: 76%) in in vitro senescent late-passage cells compared to early-passage cells, suggesting an in vitro age-related impairment of osteoblast functions. We hypothesized that decreased osteoblast functions with in vitro aging......Adequate responses to various hormones, such as 1,25-dihydroxyvitamin D(3) (calcitriol) are a prerequisite for optimal osteoblast functions. We have previously characterized several human diploid osteoblastic cell lines that exhibit typical in vitro aging characteristics during long......-term subculturing. In order to study in vitro age-related changes in osteoblast functions, we compared constitutive mRNA levels of osteoblast-specific genes in early-passage ( 90% lifespan completed). We found a significant reduction in mRNA levels...

  6. Immunotoxicity of aflatoxin B1: impairment of the cell-mediated response to vaccine antigen and modulation of cytokine expression.

    Science.gov (United States)

    Meissonnier, Guylaine M; Pinton, Philippe; Laffitte, Joëlle; Cossalter, Anne-Marie; Gong, Yun Yun; Wild, Christopher P; Bertin, Gérard; Galtier, Pierre; Oswald, Isabelle P

    2008-09-01

    Aflatoxin B1 (AFB1), a mycotoxin produced by Aspergillus flavus or A. parasiticus, is a frequent contaminant of food and feed. This toxin is hepatotoxic and immunotoxic. The present study analyzed in pigs the influence of AFB1 on humoral and cellular responses, and investigated whether the immunomodulation observed is produced through interference with cytokine expression. For 28 days, pigs were fed a control diet or a diet contaminated with 385, 867 or 1807 microg pure AFB1/kg feed. At days 4 and 15, pigs were vaccinated with ovalbumin. AFB1 exposure, confirmed by an observed dose-response in blood aflatoxin-albumin adduct, had no major effect on humoral immunity as measured by plasma concentrations of total IgA, IgG and IgM and of anti-ovalbumin IgG. Toxin exposure did not impair the mitogenic response of lymphocytes but delayed and decreased their specific proliferation in response to the vaccine antigen, suggesting impaired lymphocyte activation in pigs exposed to AFB1. The expression level of pro-inflammatory (TNF-alpha, IL-1beta, IL-6, IFN-gamma) and regulatory (IL-10) cytokines was assessed by real-time PCR in spleen. A significant up-regulation of all 5 cytokines was observed in spleen from pigs exposed to the highest dose of AFB1. In pigs exposed to the medium dose, IL-6 expression was increased and a trend towards increased IFN-gamma and IL-10 was observed. In addition we demonstrate that IL-6 impaired in vitro the antigenic- but not the mitogenic-induced proliferation of lymphocytes from control pigs vaccinated with ovalbumin. These results indicate that AFB1 dietary exposure decreases cell-mediated immunity while inducing an inflammatory response. These impairments in the immune response could participate in failure of vaccination protocols and increased susceptibility to infections described in pigs exposed to AFB1.

  7. Cellular dysfunction in diabetes as maladaptive response to mitochondrial oxidative stress.

    Science.gov (United States)

    Naudi, Alba; Jove, Mariona; Ayala, Victoria; Cassanye, Anna; Serrano, Jose; Gonzalo, Hugo; Boada, Jordi; Prat, Joan; Portero-Otin, Manuel; Pamplona, Reinald

    2012-01-01

    Oxidative stress has been implicated in diabetes long-term complications. In this paper, we summarize the growing evidence suggesting that hyperglycemia-induced overproduction of superoxide by mitochondrial electron transport chain triggers a maladaptive response by affecting several metabolic and signaling pathways involved in the pathophysiology of cellular dysfunction and diabetic complications. In particular, it is our goal to describe physiological mechanisms underlying the mitochondrial free radical production and regulation to explain the oxidative stress derived from a high intracellular glucose concentration and the resulting maladaptive response that leads to a cellular dysfunction and pathological state. Finally, we outline potential therapies for diabetes focused to the prevention of mitochondrial oxidative damage.

  8. The Yin-Yang of DNA Damage Response: Roles in Tumorigenesis and Cellular Senescence

    Directory of Open Access Journals (Sweden)

    Sang Soo Kim

    2013-01-01

    Full Text Available Senescent cells are relatively stable, lacking proliferation capacity yet retaining metabolic activity. In contrast, cancer cells are rather invasive and devastating, with uncontrolled proliferative capacity and resistance to cell death signals. Although tumorigenesis and cellular senescence are seemingly opposite pathological events, they are actually driven by a unified mechanism: DNA damage. Integrity of the DNA damage response (DDR network can impose a tumorigenesis barrier by navigating abnormal cells to cellular senescence. Compromise of DDR, possibly due to the inactivation of DDR components, may prevent cellular senescence but at the expense of tumor formation. Here we provide an overview of the fundamental role of DDR in tumorigenesis and cellular senescence, under the light of the Yin-Yang concept of Chinese philosophy. Emphasis is placed on discussing DDR outcome in the light of in vivo models. This information is critical as it can help make better decisions for clinical treatments of cancer patients.

  9. The cellular response of Saccharomyces cerevisiae to multi-walled carbon nanotubes (MWCNTs

    Directory of Open Access Journals (Sweden)

    Chantelle L. Phillips

    2015-03-01

    Full Text Available Nanoparticles (NPs especially those of carbon nanotubes (CNTs have remarkable properties that are very desirable in various biological and biomedical applications. This has necessitated the rapid study of CNT toxicities, to augment their safe use, particularly, in yeast cells. The yeast cell; Saccharomyces cerevisiae is a widely used industrial and biological organism with very limited data regarding their cellular behaviour in NPs. The current study examines the cellular response of S. cerevisiae to MWCNTs. The CNTs were produced by the swirled floating catalytic chemical vapour deposition (SFCCVD method and covalently functionalised using 1,3-dipolar cycloaddition. The CNT properties such as size, surface area, quality and surface vibrations were characterized using TEM, SEM, BET, TGA and Raman spectroscopy, respectively. The cellular uptake was confirmed with a FITC functionalised MWCNTs using 1H NMR, SEM and TEM. The CNT concentrations of 2–40 μg/ml were used to determine the cellular response through cell growth phases and cell viability characteristics. The TEM and SEM analyses showed the production of MWCNTs with an average diameter of 53 ± 12 nm and a length of 2.5 ± 0.5 μm. The cellular uptake of FITC-MWCNTs showed 100% internalisation in the yeast cells. The growth curve responses to the MWCNT doses showed no significant differences at P > 0.05 on the growth rate and viability of the S. cerevisiae cells.

  10. Dynamics of cellular immune responses in the acute phase of dengue virus infection.

    Science.gov (United States)

    Yoshida, Tomoyuki; Omatsu, Tsutomu; Saito, Akatsuki; Katakai, Yuko; Iwasaki, Yuki; Kurosawa, Terue; Hamano, Masataka; Higashino, Atsunori; Nakamura, Shinichiro; Takasaki, Tomohiko; Yasutomi, Yasuhiro; Kurane, Ichiro; Akari, Hirofumi

    2013-06-01

    In this study, we examined the dynamics of cellular immune responses in the acute phase of dengue virus (DENV) infection in a marmoset model. Here, we found that DENV infection in marmosets greatly induced responses of CD4/CD8 central memory T and NKT cells. Interestingly, the strength of the immune response was greater in animals infected with a dengue fever strain than in those infected with a dengue hemorrhagic fever strain of DENV. In contrast, when animals were re-challenged with the same DENV strain used for primary infection, the neutralizing antibody induced appeared to play a critical role in sterilizing inhibition against viral replication, resulting in strong but delayed responses of CD4/CD8 central memory T and NKT cells. The results in this study may help to better understand the dynamics of cellular and humoral immune responses in the control of DENV infection.

  11. Longevity and composition of cellular immune responses following experimental Plasmodium falciparum malaria infection in humans.

    Directory of Open Access Journals (Sweden)

    Anne C Teirlinck

    2011-12-01

    Full Text Available Cellular responses to Plasmodium falciparum parasites, in particular interferon-gamma (IFNγ production, play an important role in anti-malarial immunity. However, clinical immunity to malaria develops slowly amongst naturally exposed populations, the dynamics of cellular responses in relation to exposure are difficult to study and data about the persistence of such responses are controversial. Here we assess the longevity and composition of cellular immune responses following experimental malaria infection in human volunteers. We conducted a longitudinal study of cellular immunological responses to sporozoites (PfSpz and asexual blood-stage (PfRBC malaria parasites in naïve human volunteers undergoing single (n = 5 or multiple (n = 10 experimental P. falciparum infections under highly controlled conditions. IFNγ and interleukin-2 (IL-2 responses following in vitro re-stimulation were measured by flow-cytometry prior to, during and more than one year post infection. We show that cellular responses to both PfSpz and PfRBC are induced and remain almost undiminished up to 14 months after even a single malaria episode. Remarkably, not only 'adaptive' but also 'innate' lymphocyte subsets contribute to the increased IFNγ response, including αβT cells, γδT cells and NK cells. Furthermore, results from depletion and autologous recombination experiments of lymphocyte subsets suggest that immunological memory for PfRBC is carried within both the αβT cells and γδT compartments. Indeed, the majority of cytokine producing T lymphocytes express an CD45RO(+ CD62L(- effector memory (EM phenotype both early and late post infection. Finally, we demonstrate that malaria infection induces and maintains polyfunctional (IFNγ(+IL-2(+ EM responses against both PfRBC and PfSpz, previously found to be associated with protection. These data demonstrate that cellular responses can be readily induced and are long-lived following infection with P

  12. Cellular responses to elevated light levels in Fucus spiralis embryos during the first days after fertilization

    NARCIS (Netherlands)

    Coelho, S.; Rijstenbil, J.W.; Sousa-Pinto, I.; Brown, M.

    2001-01-01

    Cellular responses of 1-, 2- and 4-d-old Fucus spiralis embryos subjected to a single dose of elevated photosynthetically active photon flux density (PPFD), with or without ultraviolet (U-V) radiation, were investigated by measuring the effects on the effective quantum yield of photosystem II

  13. Cellular response of mucociliary differentiated primary bronchial epithelial cells to diesel exhaust

    NARCIS (Netherlands)

    Zarcone, M.C.; Duistermaat, E.; Schadewijk, A. van; Jedynksa, A.D.; Hiemstra, P.S.; Kooter, I.M.

    2016-01-01

    Cellular response of mucociliary differentiated primary bronchial epithelial cells to diesel exhaust. Am J Physiol Lung Cell Mol Physiol 311: L111–L123, 2016. First published May 17, 2016; doi:10.1152/ajplung.00064.2016.—Diesel emissions are the main source of air pollution in urban areas, and diese

  14. A mathematical model representing cellular immune development and response to Salmonella of chicken intestinal tissue

    NARCIS (Netherlands)

    Schokker, D.; Bannink, A.; Smits, M.A.; Rebel, J.M.J.

    2013-01-01

    The aim of this study was to create a dynamic mathematical model of the development of the cellular branch of the intestinal immune system of poultry during the first 42 days of life and of its response towards an oral infection with Salmonella enterica serovar Enteritidis. The system elements were

  15. Cellular response of mucociliary differentiated primary bronchial epithelial cells to diesel exhaust

    NARCIS (Netherlands)

    Zarcone, M.C.; Duistermaat, E.; Schadewijk, A. van; Jedynksa, A.D.; Hiemstra, P.S.; Kooter, I.M.

    2016-01-01

    Cellular response of mucociliary differentiated primary bronchial epithelial cells to diesel exhaust. Am J Physiol Lung Cell Mol Physiol 311: L111–L123, 2016. First published May 17, 2016; doi:10.1152/ajplung.00064.2016.—Diesel emissions are the main source of air pollution in urban areas, and

  16. Role of p53 in the cellular response following oleic acid accumulation in Chang liver cells.

    Science.gov (United States)

    Park, Eun-Jung; Lee, Ah Young; Chang, Seung-Hee; Yu, Kyeong-Nam; Kim, Jae-Ho; Cho, Myung-Haing

    2014-01-03

    Abnormal accumulation of fatty acids triggers the harmful cellular response called lipotoxicity. In this study, we investigated the cellular response following accumulation of oleic acid (OA), a monounsaturated fatty acid, in human Chang liver cells. OA droplets were distributed freely in the cytoplasm and/or degraded within lysosomes. OA exposure increased ATP production and concomitantly dilated mitochondria. At 24h after OA exposure, cell viability decreased slightly and was coupled with a reduction in mitochondrial Ca(2+) concentration, the alteration in cell viability was also associated with the generation of reactive oxygen species and changes in the cell cycle. Moreover, OA treatment increased the expression of autophagy- and apoptotic cell death-related proteins in a dose-dependent manner. Furthermore, we investigated the role of p53, a tumor suppressor protein, in the cellular response elicited by OA accumulation. OA-induced changes in cell viability and ATP production were rescued to control levels when cells were pretreated with pifithrin-alpha (PTA), a p53 inhibitor. By contrast, the expressions of LC3-II and perilipin, proteins required for lipophagy, were down-regulated by PTA pretreatment. Taken together, our results suggest that p53 plays a key role in the cellular response elicited by OA accumulation in Chang liver cells.

  17. Glucocorticoids mediate stress-induced impairment of retrieval of stimulus-response memory.

    Science.gov (United States)

    Atsak, Piray; Guenzel, Friederike M; Kantar-Gok, Deniz; Zalachoras, Ioannis; Yargicoglu, Piraye; Meijer, Onno C; Quirarte, Gina L; Wolf, Oliver T; Schwabe, Lars; Roozendaal, Benno

    2016-05-01

    Acute stress and elevated glucocorticoid hormone levels are well known to impair the retrieval of hippocampus-dependent 'declarative' memory. Recent findings suggest that stress might also impair the retrieval of non-hippocampal memories. In particular, stress shortly before retention testing was shown to impair the retrieval of striatal stimulus-response associations in humans. However, the mechanism underlying this stress-induced retrieval impairment of non-hippocampal stimulus-response memory remains elusive. In the present study, we investigated whether an acute elevation in glucocorticoid levels mediates the impairing effects of stress on retrieval of stimulus-response memory. Male Sprague-Dawley rats were trained on a stimulus-response task in an eight-arm radial maze until they learned to associate a stimulus, i.e., cue, with a food reward in one of the arms. Twenty-four hours after successful acquisition, they received a systemic injection of vehicle, corticosterone (1mg/kg), the corticosterone-synthesis inhibitor metyrapone (35mg/kg) or were left untreated 1h before retention testing. We found that the corticosterone injection impaired the retrieval of stimulus-response memory. We further found that the systemic injection procedure per se was stressful as the vehicle administration also increased plasma corticosterone levels and impaired the retrieval of stimulus-response memory. However, memory retrieval was not impaired when rats were tested 2min after the systemic vehicle injection, before any stress-induced elevation in corticosterone levels had occurred. Moreover, metyrapone treatment blocked the effect of injection stress on both plasma corticosterone levels and memory retrieval impairment, indicating that the endogenous corticosterone response mediates the stress-induced memory retrieval impairment. None of the treatments affected rats' locomotor activity or motivation to search for the food reward within the maze. These findings show that stress

  18. Cellular and humoral local immune responses in sheep experimentally infected with Oestrus ovis (Diptera: Oestridae).

    Science.gov (United States)

    Tabouret, Guillaume; Lacroux, Caroline; Andreoletti, Olivier; Bergeaud, Jean Paul; Hailu-Tolosa, Yacob; Hoste, Hervé; Prevot, Françoise; Grisez, Christelle; Dorchies, Philippe; Jacquiet, Philippe

    2003-01-01

    Cellular and humoral local responses were investigated following repetitive artificial Oestrus ovis infections in lambs. The presence of larvae induced a huge local recruitment of either leucocytes (T and B lymphocytes, macrophages) or granulocytes (eosinophils, mast cells and globule leucocytes). This cellular response was more pronounced in the ethmoid and sinus (development sites of second and third instar larvae) than in the septum or turbinates where first instar larvae migrate. Infected lambs produced Oestrus ovis specific IgG and IgA antibodies in their mucus. This local humoral response was mainly directed against larval salivary gland antigens and not against larval digestive tract antigens. Compared to the control animals, the sinusal mucosa of infected animals was extremely thickened and the epithelium exhibited hyperplasia, metaplasia and eosinophilic exocytosis. The possible roles of these local immune responses in the regulation of O. ovis larvae populations in sheep are discussed.

  19. Involvement of Noxa in mediating cellular ER stress responses to lytic virus infection

    OpenAIRE

    2011-01-01

    Noxa is a Bcl-2 homology domain-containing pro-apoptotic mitochondrial protein. Noxa mRNA and protein expression are upregulated by dsRNA or virus, and ectopic Noxa expression enhances cellular sensitivity to virus or dsRNA-induced apoptosis. Here we demonstrate that Noxa null baby mouse kidney (BMK) cells are deficient in normal cytopathic response to lytic viruses, and that reconstitution of the knockout cells with wild type Noxa restored normal cytopathic responses. Noxa regulation by viru...

  20. Metabolic autofluorescence imaging of head and neck cancer organoids quantifies cellular heterogeneity and treatment response (Conference Presentation)

    Science.gov (United States)

    Shah, Amy T.; Heaster, Tiffany M.; Skala, Melissa C.

    2017-02-01

    Treatment options for head and neck cancer are limited, and can cause an impaired ability to eat, talk, and breathe. Therefore, optimized and personalized therapies could reduce unnecessary toxicities from ineffective treatments. Organoids are generated from primary tumor tissue and provide a physiologically-relevant in vitro model to measure drug response. Additionally, multiphoton fluorescence lifetime imaging (FLIM) of the metabolic cofactors NAD(P)H and FAD can resolve dynamic cellular response to anti-cancer treatment. This study applies FLIM of NAD(P)H and FAD to head and neck cancer organoids. Head and neck cancer tissue was digested and grown in culture as three-dimensional organoids. Gold standard measures of therapeutic response in vivo indicate stable disease after treatment with cetuximab (antibody therapy) or cisplatin (chemotherapy), and treatment response after combination treatment. In parallel, organoids were treated with cetuximab, cisplatin, or combination therapy for 24 hours. Treated organoids exhibit decreased NAD(P)H lifetime (pquality of life and treatment outcomes for head and neck cancer patients.

  1. Intraspecies variability in the dose-response relationship for Salmonella Enteritidis associated with genetic differences in cellular immune response.

    NARCIS (Netherlands)

    Havelaar, A.H.; Garssen, J.; Takumi, K.; Koedam, M.I.; Ritmeester, W.; Fonteyne, L. de la; Bousema, T.; Vos, J.

    2004-01-01

    To evaluate the effects of differences in host cellular immunity, we studied the dose-response relationship for infection with Salmonella enterica serovar Enteritidis (SE) in two different rat strains, skewed towards T helper 1 (Th1, Lewis rats) or T helper 2 (Th2, Brown Norway rats) immunoregulatio

  2. Global functional analyses of cellular responses to pore-forming toxins.

    Directory of Open Access Journals (Sweden)

    Cheng-Yuan Kao

    2011-03-01

    Full Text Available Here we present the first global functional analysis of cellular responses to pore-forming toxins (PFTs. PFTs are uniquely important bacterial virulence factors, comprising the single largest class of bacterial protein toxins and being important for the pathogenesis in humans of many Gram positive and Gram negative bacteria. Their mode of action is deceptively simple, poking holes in the plasma membrane of cells. The scattered studies to date of PFT-host cell interactions indicate a handful of genes are involved in cellular defenses to PFTs. How many genes are involved in cellular defenses against PFTs and how cellular defenses are coordinated are unknown. To address these questions, we performed the first genome-wide RNA interference (RNAi screen for genes that, when knocked down, result in hypersensitivity to a PFT. This screen identifies 106 genes (∼0.5% of genome in seven functional groups that protect Caenorhabditis elegans from PFT attack. Interactome analyses of these 106 genes suggest that two previously identified mitogen-activated protein kinase (MAPK pathways, one (p38 studied in detail and the other (JNK not, form a core PFT defense network. Additional microarray, real-time PCR, and functional studies reveal that the JNK MAPK pathway, but not the p38 MAPK pathway, is a key central regulator of PFT-induced transcriptional and functional responses. We find C. elegans activator protein 1 (AP-1; c-jun, c-fos is a downstream target of the JNK-mediated PFT protection pathway, protects C. elegans against both small-pore and large-pore PFTs and protects human cells against a large-pore PFT. This in vivo RNAi genomic study of PFT responses proves that cellular commitment to PFT defenses is enormous, demonstrates the JNK MAPK pathway as a key regulator of transcriptionally-induced PFT defenses, and identifies AP-1 as the first cellular component broadly important for defense against large- and small-pore PFTs.

  3. Abnormal Cell Responses and Role of TNF-α in Impaired Diabetic Wound Healing

    Directory of Open Access Journals (Sweden)

    Fanxing Xu

    2013-01-01

    Full Text Available Impaired diabetic wound healing constitutes a major health problem. The impaired healing is caused by complex factors such as abnormal keratinocyte and fibroblast migration, proliferation, differentiation, and apoptosis, abnormal macrophage polarization, impaired recruitment of mesenchymal stem cells (MSCs and endothelial progenitor cells (EPCs, and decreased vascularization. Diabetes-enhanced and prolonged expression of TNF-α also contributes to impaired healing. In this paper, we discuss the abnormal cell responses in diabetic wound healing and the contribution of TNF-α.

  4. Silver Nanoparticle-Mediated Cellular Responses in Various Cell Lines: An in Vitro Model

    Science.gov (United States)

    Zhang, Xi-Feng; Shen, Wei; Gurunathan, Sangiliyandi

    2016-01-01

    Silver nanoparticles (AgNPs) have attracted increased interest and are currently used in various industries including medicine, cosmetics, textiles, electronics, and pharmaceuticals, owing to their unique physical and chemical properties, particularly as antimicrobial and anticancer agents. Recently, several studies have reported both beneficial and toxic effects of AgNPs on various prokaryotic and eukaryotic systems. To develop nanoparticles for mediated therapy, several laboratories have used a variety of cell lines under in vitro conditions to evaluate the properties, mode of action, differential responses, and mechanisms of action of AgNPs. In vitro models are simple, cost-effective, rapid, and can be used to easily assess efficacy and performance. The cytotoxicity, genotoxicity, and biocompatibility of AgNPs depend on many factors such as size, shape, surface charge, surface coating, solubility, concentration, surface functionalization, distribution of particles, mode of entry, mode of action, growth media, exposure time, and cell type. Cellular responses to AgNPs are different in each cell type and depend on the physical and chemical nature of AgNPs. This review evaluates significant contributions to the literature on biological applications of AgNPs. It begins with an introduction to AgNPs, with particular attention to their overall impact on cellular effects. The main objective of this review is to elucidate the reasons for different cell types exhibiting differential responses to nanoparticles even when they possess similar size, shape, and other parameters. Firstly, we discuss the cellular effects of AgNPs on a variety of cell lines; Secondly, we discuss the mechanisms of action of AgNPs in various cellular systems, and try to elucidate how AgNPs interact with different mammalian cell lines and produce significant effects; Finally, we discuss the cellular activation of various signaling molecules in response to AgNPs, and conclude with future perspectives

  5. Silver Nanoparticle-Mediated Cellular Responses in Various Cell Lines: An in Vitro Model

    Directory of Open Access Journals (Sweden)

    Xi-Feng Zhang

    2016-09-01

    Full Text Available Silver nanoparticles (AgNPs have attracted increased interest and are currently used in various industries including medicine, cosmetics, textiles, electronics, and pharmaceuticals, owing to their unique physical and chemical properties, particularly as antimicrobial and anticancer agents. Recently, several studies have reported both beneficial and toxic effects of AgNPs on various prokaryotic and eukaryotic systems. To develop nanoparticles for mediated therapy, several laboratories have used a variety of cell lines under in vitro conditions to evaluate the properties, mode of action, differential responses, and mechanisms of action of AgNPs. In vitro models are simple, cost-effective, rapid, and can be used to easily assess efficacy and performance. The cytotoxicity, genotoxicity, and biocompatibility of AgNPs depend on many factors such as size, shape, surface charge, surface coating, solubility, concentration, surface functionalization, distribution of particles, mode of entry, mode of action, growth media, exposure time, and cell type. Cellular responses to AgNPs are different in each cell type and depend on the physical and chemical nature of AgNPs. This review evaluates significant contributions to the literature on biological applications of AgNPs. It begins with an introduction to AgNPs, with particular attention to their overall impact on cellular effects. The main objective of this review is to elucidate the reasons for different cell types exhibiting differential responses to nanoparticles even when they possess similar size, shape, and other parameters. Firstly, we discuss the cellular effects of AgNPs on a variety of cell lines; Secondly, we discuss the mechanisms of action of AgNPs in various cellular systems, and try to elucidate how AgNPs interact with different mammalian cell lines and produce significant effects; Finally, we discuss the cellular activation of various signaling molecules in response to AgNPs, and conclude with

  6. Intraspecific variation in cellular and biochemical heat response strategies of Mediterranean Xeropicta derbentina [Pulmonata, Hygromiidae].

    Directory of Open Access Journals (Sweden)

    Sandra Troschinski

    Full Text Available Dry and hot environments challenge the survival of terrestrial snails. To minimize overheating and desiccation, physiological and biochemical adaptations are of high importance for these animals. In the present study, seven populations of the Mediterranean land snail species Xeropicta derbentina were sampled from their natural habitat in order to investigate the intraspecific variation of cellular and biochemical mechanisms, which are assigned to contribute to heat resistance. Furthermore, we tested whether genetic parameters are correlated with these physiological heat stress response patterns. Specimens of each population were individually exposed to elevated temperatures (25 to 52°C for 8 h in the laboratory. After exposure, the health condition of the snails' hepatopancreas was examined by means of qualitative description and semi-quantitative assessment of histopathological effects. In addition, the heat-shock protein 70 level (Hsp70 was determined. Generally, calcium cells of the hepatopancreas were more heat resistant than digestive cells - this phenomenon was associated with elevated Hsp70 levels at 40°C.We observed considerable variation in the snails' heat response strategy: Individuals from three populations invested much energy in producing a highly elevated Hsp70 level, whereas three other populations invested energy in moderate stress protein levels - both strategies were in association with cellular functionality. Furthermore, one population kept cellular condition stable despite a low Hsp70 level until 40°C exposure, whereas prominent cellular reactions were observed above this thermal limit. Genetic diversity (mitochondrial cytochrome c oxidase subunit I gene within populations was low. Nevertheless, when using genetic indices as explanatory variables in a multivariate regression tree (MRT analysis, population structure explained mean differences in cellular and biochemical heat stress responses, especially in the group

  7. The binding of NCAM to FGFR1 induces a specific cellular response mediated by receptor trafficking

    DEFF Research Database (Denmark)

    Francavilla, Chiara; Cattaneo, Paola; Berezin, Vladimir

    2009-01-01

    different from that elicited by FGF-2. In contrast to FGF-induced degradation of endocytic FGFR1, NCAM promotes the stabilization of the receptor, which is recycled to the cell surface in a Rab11- and Src-dependent manner. In turn, FGFR1 recycling is required for NCAM-induced sustained activation of various...... effectors. Furthermore, NCAM, but not FGF-2, promotes cell migration, and this response depends on FGFR1 recycling and sustained Src activation. Our results implicate NCAM as a nonconventional ligand for FGFR1 that exerts a peculiar control on the intracellular trafficking of the receptor, resulting...... in a specific cellular response. Besides introducing a further level of complexity in the regulation of FGFR1 function, our findings highlight the link of FGFR recycling with sustained signaling and cell migration and the critical role of these events in dictating the cellular response evoked by receptor...

  8. Immunologic Monitoring of Cellular Responses by Dendritic/Tumor Cell Fusion Vaccines

    Directory of Open Access Journals (Sweden)

    Shigeo Koido

    2011-01-01

    Full Text Available Although dendritic cell (DC- based cancer vaccines induce effective antitumor activities in murine models, only limited therapeutic results have been obtained in clinical trials. As cancer vaccines induce antitumor activities by eliciting or modifying immune responses in patients with cancer, the Response Evaluation Criteria in Solid Tumors (RECIST and WHO criteria, designed to detect early effects of cytotoxic chemotherapy in solid tumors, may not provide a complete assessment of cancer vaccines. The problem may, in part, be resolved by carrying out immunologic cellular monitoring, which is one prerequisite for rational development of cancer vaccines. In this review, we will discuss immunologic monitoring of cellular responses for the evaluation of cancer vaccines including fusions of DC and whole tumor cell.

  9. Dehydroepiandrosterone and metyrapone partially restore the adaptive humoral and cellular immune response in endotoxin immunosuppressed mice.

    Science.gov (United States)

    Rearte, Bárbara; Maglioco, Andrea; Machuca, Damián; Greco, Daiana Martire; Landoni, Verónica I; Rodriguez-Rodrigues, Nahuel; Meiss, Roberto; Fernández, Gabriela C; Isturiz, Martín A

    2014-08-01

    Prior exposure to endotoxins renders the host temporarily refractory to subsequent endotoxin challenge (endotoxin tolerance). Clinically, this state has also been pointed out as the initial cause of the non-specific humoral and cellular immunosuppression described in these patients. We recently demonstrated the restoration of immune response with mifepristone (RU486), a receptor antagonist of glucocorticoids. Here we report the treatment with other modulators of glucocorticoids, i.e. dehydroepiandrosterone (DHEA), a hormone with anti-glucocorticoid properties, or metyrapone (MET) an inhibitor of corticosterone synthesis. These drugs were able to partially, but significantly, restore the humoral immune response in immunosuppressed mice. A significant recovery of proliferative responsiveness was also observed when splenocytes were obtained from DHEA- or MET-treated immunosuppressed mice. In addition, these treatments restored the hypersensitivity response in immunosuppressed mice. Finally, although neither DHEA nor MET improved the reduced CD4 lymphocyte count in spleen from immunosuppressed mice, both treatments promoted spleen architecture reorganization, partially restoring the distinct cellular components and their localization in the spleen. The results from this study indicate that DHEA and MET could play an important role in the restoration of both adaptive humoral and cellular immune response in LPS-immunosuppressed mice, reinforcing the concept of a central involvement of endogenous glucocorticoids on this phenomenon. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  10. Function of Membrane Rafts in Viral Lifecycles and Host Cellular Response

    Directory of Open Access Journals (Sweden)

    Tadanobu Takahashi

    2011-01-01

    Full Text Available Membrane rafts are small (10–200 nm sterol- and sphingolipid-enriched domains that compartmentalize cellular processes. Membrane rafts play an important role in viral infection cycles and viral virulence. Viruses are divided into four main classes, enveloped DNA virus, enveloped RNA virus, nonenveloped DNA virus, and nonenveloped RNA virus. General virus infection cycle is also classified into two sections, the early stage (entry process and the late stage (assembly, budding, and release processes of virus particles. In the viral cycle, membrane rafts act as a scaffold of many cellular signal transductions, which are associated with symptoms caused by viral infections. In this paper, we describe the functions of membrane rafts in viral lifecycles and host cellular response according to each virus classification, each stage of the virus lifecycle, and each virus-induced signal transduction.

  11. Relative roles of the cellular and humoral responses in the Drosophila host defense against three gram-positive bacterial infections.

    Directory of Open Access Journals (Sweden)

    Nadine T Nehme

    Full Text Available BACKGROUND: Two NF-kappaB signaling pathways, Toll and immune deficiency (imd, are required for survival to bacterial infections in Drosophila. In response to septic injury, these pathways mediate rapid transcriptional activation of distinct sets of effector molecules, including antimicrobial peptides, which are important components of a humoral defense response. However, it is less clear to what extent macrophage-like hemocytes contribute to host defense. METHODOLOGY/PRINCIPAL FINDINGS: In order to dissect the relative importance of humoral and cellular defenses after septic injury with three different gram-positive bacteria (Micrococcus luteus, Enterococcus faecalis, Staphylococcus aureus, we used latex bead pre-injection to ablate macrophage function in flies wildtype or mutant for various Toll and imd pathway components. We found that in all three infection models a compromised phagocytic system impaired fly survival--independently of concomitant Toll or imd pathway activation. Our data failed to confirm a role of the PGRP-SA and GNBP1 Pattern Recognition Receptors for phagocytosis of S. aureus. The Drosophila scavenger receptor Eater mediates the phagocytosis by hemocytes or S2 cells of E. faecalis and S. aureus, but not of M. luteus. In the case of M. luteus and E. faecalis, but not S. aureus, decreased survival due to defective phagocytosis could be compensated for by genetically enhancing the humoral immune response. CONCLUSIONS/SIGNIFICANCE: Our results underscore the fundamental importance of both cellular and humoral mechanisms in Drosophila immunity and shed light on the balance between these two arms of host defense depending on the invading pathogen.

  12. Cellular response to low dose radiation: Role of phosphatidylinositol-3 kinase like kinases

    Energy Technology Data Exchange (ETDEWEB)

    Balajee, A.S.; Meador, J.A.; Su, Y.

    2011-03-24

    It is increasingly realized that human exposure either to an acute low dose or multiple chronic low doses of low LET radiation has the potential to cause different types of cancer. Therefore, the central theme of research for DOE and NASA is focused on understanding the molecular mechanisms and pathways responsible for the cellular response to low dose radiation which would not only improve the accuracy of estimating health risks but also help in the development of predictive assays for low dose radiation risks associated with tissue degeneration and cancer. The working hypothesis for this proposal is that the cellular mechanisms in terms of DNA damage signaling, repair and cell cycle checkpoint regulation are different for low and high doses of low LET radiation and that the mode of action of phosphatidylinositol-3 kinase like kinases (PIKK: ATM, ATR and DNA-PK) determines the dose dependent cellular responses. The hypothesis will be tested at two levels: (I) Evaluation of the role of ATM, ATR and DNA-PK in cellular response to low and high doses of low LET radiation in simple in vitro human cell systems and (II) Determination of radiation responses in complex cell microenvironments such as human EpiDerm tissue constructs. Cellular responses to low and high doses of low LET radiation will be assessed from the view points of DNA damage signaling, DNA double strand break repair and cell cycle checkpoint regulation by analyzing the activities (i.e. post-translational modifications and kinetics of protein-protein interactions) of the key target proteins for PI-3 kinase like kinases both at the intra-cellular and molecular levels. The proteins chosen for this proposal are placed under three categories: (I) sensors/initiators include ATM ser1981, ATR, 53BP1, gamma-H2AX, MDC1, MRE11, Rad50 and Nbs1; (II) signal transducers include Chk1, Chk2, FANCD2 and SMC1; and (III) effectors include p53, CDC25A and CDC25C. The primary goal of this proposal is to elucidate the

  13. The involvement of XPC protein in the cisplatin DNA damaging treatment-mediated cellular response

    Institute of Scientific and Technical Information of China (English)

    Gan WANG; Alan DOMBKOWSKI; Lynn CHUANG; Xiao Xin S XU

    2004-01-01

    Recognition of DNA damage is a critical step for DNA damage-mediated cellular response. XPC is an important DNA damage recognition protein involved in nucleotide excision repair (NER). We have studied the XPC protein in cisplatin DNA damaging treatment-mediated cellular response. Comparison of the microarray data from both normal and XPCdefective human fibroblasts identified 861 XPC-responsive genes in the cisplatin treatment (with minimum fold change≥1.5).The cell cycle and cell proliferation-related genes are the most affected genes by the XPC defect in the treatment. Many other cellular function genes, especially the DNA repair and signal transduction-related genes, were also affected by the XPC defect in the treatment. To validate the microarray data, the transcription levels of some microarray-identified genes were also determined by an RT-PCR based real time PCR assay. The real time PCR results are consistent with the microarray data for most of the tested genes, indicating the reliability of the microarray data. To further validate the microarray data, the cisplatin treatment-mediated caspase-3 activation was also determined. The Western blot hybridization results indicate that the XPC defect greatly attenuates the cisplatin treatment-mediated Caspase-3 activation. We elucidated the role of p53 protein in the XPC protein DNA damage recognition-mediated signaling process. The XPC defect reduces the cisplatin treatment-mediated p53 response. These results suggest that the XPC protein plays an important role in the cisplatin treatment-mediated cellular response. It may also suggest a possible mechanism of cancer cell drug resistance.

  14. Elucidating the molecular mechanisms underlying cellular response to biophysical cues using synthetic biology approaches.

    Science.gov (United States)

    Denning, Denise; Roos, Wouter H

    2016-09-02

    The use of synthetic surfaces and materials to influence and study cell behavior has vastly progressed our understanding of the underlying molecular mechanisms involved in cellular response to physicochemical and biophysical cues. Reconstituting cytoskeletal proteins and interfacing them with a defined microenvironment has also garnered deep insight into the engineering mechanisms existing within the cell. This review presents recent experimental findings on the influence of several parameters of the extracellular environment on cell behavior and fate, such as substrate topography, stiffness, chemistry and charge. In addition, the use of synthetic environments to measure physical properties of the reconstituted cytoskeleton and their interaction with intracellular proteins such as molecular motors is discussed, which is relevant for understanding cell migration, division and structural integrity, as well as intracellular transport. Insight is provided regarding the next steps to be taken in this interdisciplinary field, in order to achieve the global aim of artificially directing cellular response.

  15. Review on Impedance Detection of Cellular Responses in Micro/Nano Environment

    Directory of Open Access Journals (Sweden)

    Kin Fong Lei

    2014-01-01

    Full Text Available In general, cell culture-based assays, investigations of cell number, viability, and metabolic activities during culture periods, are commonly performed to study the cellular responses under various culture conditions explored. Quantification of cell numbers can provide the information of cell proliferation. Cell viability study can understand the percentage of cell death under a specific tested substance. Monitoring of the metabolic activities is an important index for the study of cell physiology. Based on the development of microfluidic technology, microfluidic systems incorporated with impedance measurement technique, have been reported as a new analytical approach for cell culture-based assays. The aim of this article is to review recent developments on the impedance detection of cellular responses in micro/nano environment. These techniques provide an effective and efficient technique for cell culture-based assays.

  16. JAK/STAT signaling in Drosophila muscles controls the cellular immune response against parasitoid infection.

    Science.gov (United States)

    Yang, Hairu; Kronhamn, Jesper; Ekström, Jens-Ola; Korkut, Gül Gizem; Hultmark, Dan

    2015-12-01

    The role of JAK/STAT signaling in the cellular immune response of Drosophila is not well understood. Here, we show that parasitoid wasp infection activates JAK/STAT signaling in somatic muscles of the Drosophila larva, triggered by secretion of the cytokines Upd2 and Upd3 from circulating hemocytes. Deletion of upd2 or upd3, but not the related os (upd1) gene, reduced the cellular immune response, and suppression of the JAK/STAT pathway in muscle cells reduced the encapsulation of wasp eggs and the number of circulating lamellocyte effector cells. These results suggest that JAK/STAT signaling in muscles participates in a systemic immune defense against wasp infection.

  17. Network analysis of oyster transcriptome revealed a cascade of cellular responses during recovery after heat shock.

    Directory of Open Access Journals (Sweden)

    Lingling Zhang

    Full Text Available Oysters, as a major group of marine bivalves, can tolerate a wide range of natural and anthropogenic stressors including heat stress. Recent studies have shown that oysters pretreated with heat shock can result in induced heat tolerance. A systematic study of cellular recovery from heat shock may provide insights into the mechanism of acquired thermal tolerance. In this study, we performed the first network analysis of oyster transcriptome by reanalyzing microarray data from a previous study. Network analysis revealed a cascade of cellular responses during oyster recovery after heat shock and identified responsive gene modules and key genes. Our study demonstrates the power of network analysis in a non-model organism with poor gene annotations, which can lead to new discoveries that go beyond the focus on individual genes.

  18. Cytokine, antibody and proliferative cellular responses elicited by Taenia solium calreticulin upon experimental infection in hamsters.

    Science.gov (United States)

    Mendlovic, Fela; Cruz-Rivera, Mayra; Ávila, Guillermina; Vaughan, Gilberto; Flisser, Ana

    2015-01-01

    Taenia solium causes two diseases in humans, cysticercosis and taeniosis. Tapeworm carriers are the main risk factor for neurocysticercosis. Limited information is available about the immune response elicited by the adult parasite, particularly the induction of Th2 responses, frequently associated to helminth infections. Calreticulin is a ubiquitous, multifunctional protein involved in cellular calcium homeostasis, which has been suggested to play a role in the regulation of immune responses. In this work, we assessed the effect of recombinant T. solium calreticulin (rTsCRT) on the cytokine, humoral and cellular responses upon experimental infection in Syrian Golden hamsters (Mesocricetus auratus). Animals were infected with T. solium cysticerci and euthanized at different times after infection. Specific serum antibodies, proliferative responses in mesenteric lymph nodes and spleen cells, as well as cytokines messenger RNA (mRNA) were analyzed. The results showed that one third of the infected animals elicited anti-rTsCRT IgG antibodies. Interestingly, mesenteric lymph node (MLN) cells from either infected or non-infected animals did not proliferate upon in vitro stimulation with rTsCRT. Additionally, stimulation with a tapeworm crude extract resulted in increased expression of IL-4 and IL-5 mRNA. Upon stimulation, rTsCRT increased the expression levels of IL-10 in spleen and MLN cells from uninfected and infected hamsters. The results showed that rTsCRT favors a Th2-biased immune response characterized by the induction of IL-10 in mucosal and systemic lymphoid organs. Here we provide the first data on the cytokine, antibody and cellular responses to rTsCRT upon in vitro stimulation during taeniasis.

  19. Cellular graded responses and ventricular vulnerability to reentry by a premature stimulus in isolated canine ventricle.

    Science.gov (United States)

    Gotoh, M; Uchida, T; Mandel, W J; Fishbein, M C; Chen, P S; Karagueuzian, H S

    1997-04-15

    The cellular mechanism by which a point strong premature stimulus (S2) induces reentry is unknown. We hypothesized that cellular graded responses induced by an S2 mediate and control tissue vulnerability to reentry. Reentry is induced in normal canine ventricular epicardial slices (30x38x2 mm, n=30) by an S2 at intervals shorter than the effective refractory period. The S1 is applied at the edge and the S2 at the center of the tissue. The line connecting the S1-S2 sites is parallel to the long axis of the fiber orientation. Isochronal activation maps were constructed with 56 to 480 bipolar electrodes, and the activation pattern was visualized dynamically. Reentry induced by an S2 is mediated by the graded responses as follows: The induced graded responses propagate with decrement toward recovered cells. When the amplitude of the propagated depolarizing graded responses reaches threshold relative to the recovering cells, an action potential is initiated along the fiber 2 to 3 mm away from the cathode of the S2. The distally initiated activation wave front blocks near the S2 site because the same S2-induced graded response prolongs the refractory period. The "broken" wave front then circulates around both sides of the block and reenters when the site of block recovers its excitability, completing the first figure-eight reentry cycle. Reentry cannot be induced when the S2 strength is >72+/-21 mA (upper limit of vulnerability) because these strong S2-induced graded responses convert the unidirectional block to bidirectional block by excess prolongation of the refractoriness. We conclude that the magnitude and the propagation of S2-induced cellular graded responses mediate and control vulnerability to reentry in the ventricular epicardium.

  20. Cytokine, antibody and proliferative cellular responses elicited by Taenia solium calreticulin upon experimental infection in hamsters.

    Directory of Open Access Journals (Sweden)

    Fela Mendlovic

    Full Text Available Taenia solium causes two diseases in humans, cysticercosis and taeniosis. Tapeworm carriers are the main risk factor for neurocysticercosis. Limited information is available about the immune response elicited by the adult parasite, particularly the induction of Th2 responses, frequently associated to helminth infections. Calreticulin is a ubiquitous, multifunctional protein involved in cellular calcium homeostasis, which has been suggested to play a role in the regulation of immune responses. In this work, we assessed the effect of recombinant T. solium calreticulin (rTsCRT on the cytokine, humoral and cellular responses upon experimental infection in Syrian Golden hamsters (Mesocricetus auratus. Animals were infected with T. solium cysticerci and euthanized at different times after infection. Specific serum antibodies, proliferative responses in mesenteric lymph nodes and spleen cells, as well as cytokines messenger RNA (mRNA were analyzed. The results showed that one third of the infected animals elicited anti-rTsCRT IgG antibodies. Interestingly, mesenteric lymph node (MLN cells from either infected or non-infected animals did not proliferate upon in vitro stimulation with rTsCRT. Additionally, stimulation with a tapeworm crude extract resulted in increased expression of IL-4 and IL-5 mRNA. Upon stimulation, rTsCRT increased the expression levels of IL-10 in spleen and MLN cells from uninfected and infected hamsters. The results showed that rTsCRT favors a Th2-biased immune response characterized by the induction of IL-10 in mucosal and systemic lymphoid organs. Here we provide the first data on the cytokine, antibody and cellular responses to rTsCRT upon in vitro stimulation during taeniasis.

  1. Cellular Response of the Amoeba Acanthamoeba castellanii to Chlorine, Chlorine Dioxide, and Monochloramine Treatments ▿

    OpenAIRE

    Mogoa, Emerancienne; Bodet, Charles; Morel, Franck; Rodier, Marie-Hélène; Legube, Bernard; Héchard, Yann

    2011-01-01

    Acanthamoeba castellanii is a free-living amoebae commonly found in water systems. Free-living amoebae might be pathogenic but are also known to bear phagocytosis-resistant bacteria, protecting these bacteria from water treatments. The mode of action of these treatments is poorly understood, particularly on amoebae. It is important to examine the action of these treatments on amoebae in order to improve them. The cellular response to chlorine, chlorine dioxide, and monochloramine was tested o...

  2. Psychedelics Recruit Multiple Cellular Types and Produce Complex Transcriptional Responses Within the Brain

    OpenAIRE

    Martin, David A.; Nichols, Charles D.

    2016-01-01

    There has recently been a resurgence of interest in psychedelics, substances that profoundly alter perception and cognition and have recently demonstrated therapeutic efficacy to treat anxiety, depression, and addiction in the clinic. The receptor mechanisms that drive their molecular and behavioral effects involve activation of cortical serotonin 5-HT2A receptors, but the responses of specific cellular populations remain unknown. Here, we provide evidence that a small subset of 5-HT2A-expres...

  3. A nonstandard finite difference scheme for a basic model of cellular immune response to viral infection

    Science.gov (United States)

    Korpusik, Adam

    2017-02-01

    We present a nonstandard finite difference scheme for a basic model of cellular immune response to viral infection. The main advantage of this approach is that it preserves the essential qualitative features of the original continuous model (non-negativity and boundedness of the solution, equilibria and their stability conditions), while being easy to implement. All of the qualitative features are preserved independently of the chosen step-size. Numerical simulations of our approach and comparison with other conventional simulation methods are presented.

  4. Metal oxide nanoparticles interact with immune cells and activate different cellular responses

    OpenAIRE

    Simón-Vázquez R; Lozano-Fernández T; Dávila-Grana A; González-Fernández A

    2016-01-01

    Rosana Simón-Vázquez, Tamara Lozano-Fernández, Angela Dávila-Grana, Africa González-Fernández Immunology Laboratory, Biomedical Research Center (CINBIO) and Institute of Biomedical Research of Ourense-Pontevedra-Vigo (IBI), University of Vigo, Campus Lagoas Marcosende, Vigo, Pontevedra, Spain Abstract: Besides cell death, nanoparticles (Nps) can induce other cellular responses such as inflammation. The potential immune respon...

  5. Cellular responses and cytokine profiles in Ascaris lumbricoides and Trichuris trichiura infected patients.

    Science.gov (United States)

    Geiger, Stefan M; Massara, Cristiano L; Bethony, Jeffrey; Soboslay, Peter T; Carvalho, Omar S; Corrêa-Oliveira, Rodrigo

    2002-01-01

    The impact of intestinal helminth infection, i.e. Ascaris lumbricoides and Trichuris trichiura, on cellular responsiveness and cytokine production was investigated in young adults. Ascaris-specific cellular responsiveness was higher in parasite-free endemic controls than in patients infected with T. trichiura, or A. lumbricoides, or patients co-infected with both parasites. Also, mitogen-induced tumour necrosis factor (TNF)-alpha, interleukin (IL)-12 and interferon (IFN)-gamma secretion by peripheral blood mononuclear cells (PBMC) was higher in negative endemic controls than in infected individuals. Ascaris antigen-specific production of TNF-alpha, IL-12 and IFN-gamma was low in singly Ascaris as well as in co-infected patients, whereas secretion of IL-10 and IL-13 was elevated and similarly high in all patient groups. The detection of Trichuris-specific and Ascaris-specific IgG4 revealed significantly higher serum antibody levels in Trichuris or Ascaris patients when compared to endemic controls (P Trichuris patients with a high parasite load presented reduced cellular reactivity and lower type 1 TNF-alpha, IFN-gamma and IL-12 responses when compared with endemic controls, whereas type 2 IL-10 and IL-13 productions were similar in all groups from the endemic area. The former may support parasite persistence, whereas substantial type 2 cytokine release may promote protective immunity, suggesting an adaptation of the host to control the parasite burden while minimizing immune-mediated host self-damage.

  6. In vivo and in vitro cellular response to PEG-based hydrogels for wound repair

    Science.gov (United States)

    Waldeck, Heather

    Biomaterials are continuously being explored as a means to support, improve, or influence wound healing processes. Understanding the determining factors controlling the host response to biomaterials is crucial in developing strategies to employ materials for biomedical uses. In order to evaluate the host response to poly(ethylene glycol) (PEG)-based hydrogels, both in vivo and in vitro studies were performed to determine its efficacy as a dermal wound treatment and to investigate the mechanisms controlling cell-material interaction, respectively. The results of an in vivo study using a full thickness wound in a rat model demonstrated that both soluble and immobilized bioactive factors could be incorporated into a PEG-based semi-interpenetrating network (sIPN) to enhance the rate and the quality of dermal wound healing. To gain a better understanding of the results observed in vivo, in vitro studies were then conducted to examine the dynamics and mechanisms of the cell-material interaction. Degradation of the sIPN was explored as an influential factor in both mediating cellular response and controlling solute transport from the material. As degradation through gelatin dissolution could be influenced by simple alterations to the material formulation, these results provide facile guidelines to control the delivery of high molecular weight compounds. Further investigation of the cellular response to PEG-based biomaterials focused on key factors influencing cell-material interaction. Specifically, the role of the beta1 integrin subunit and several serum proteins (TGF-aalpha, IL-1beta and PDGF-BB) in mediating cellular response was explored. As cell-material interactions are based on commonly occurring interfaces between cells and molecules of the native extracellular environment, these studies provided insight into the mechanisms controlling the observed cellular response. Finally, the inflammatory response of primary monocytes to biomaterials was examined. Monocytes

  7. Various eicosanoids modulate the cellular and humoral immune responses of the beet armyworm, Spodoptera exigua.

    Science.gov (United States)

    Shrestha, Sony; Kim, Yonggyun

    2009-09-01

    Cyclooxygenase (COX) and lipoxygenase (LOX) can catalyze the oxidation of C20 fatty acids to produce certain eicosanoids, which play roles in mediating immune responses in insects. Despite their critical role in insect immunity, there have been few studies of the unique effects of different eicosanoids on immune responses. This study analyzed cellular and humoral immune responses of the beet armyworm, Spodoptera exigua, using seven eicosanoids selected from two major eicosanoid subgroups: prostaglandin (PG) and leukotriene (LT), derived from catalytic activities of COX and LOX respectively. Upon bacterial challenge, all seven eicosanoids (PGA(1), PGB(2), PGD(2), PGE(1), PGE(2), PGF(1alpha), and LTB(4)) significantly induced hemocyte nodulation and phagocytosis in the presence of dexamethasone, an eicosanoid biosynthesis inhibitor. However, only PGs induced cell lysis of oenocytoids to release prophenoloxidase, which resulted in an increase in phenoloxidase activity. These seven eicosanoids also induced expression of humoral immune-associated genes, including prophenoloxidase, serpin, dopa decarboxylase, cecropin, and lysozyme, in which PGB(2) and PGE(1) did not induce gene expression of prophenoloxidase. To understand the interactions between different eicosanoids, mixture effects of these eicosanoids were compared with their individual eicosanoid effects on mediating nodule formation in response to bacterial challenge. All six single PGs showed increases in nodule formation in a dose-dependent manner without significant difference among the different types. LTB(4) was more potent than the tested PGs in mediating the cellular immune response. At low doses, all combinations of two eicosanoids showed significant additive effects on nodule formation. These results indicate that immune target cells, such as hemocyte and fat body, of S. exigua can respond to different COX and LOX products to express cellular and humoral immune responses, and their overlapping, additive

  8. C/EBPγ Is a Critical Regulator of Cellular Stress Response Networks through Heterodimerization with ATF4.

    Science.gov (United States)

    Huggins, Christopher J; Mayekar, Manasi K; Martin, Nancy; Saylor, Karen L; Gonit, Mesfin; Jailwala, Parthav; Kasoji, Manjula; Haines, Diana C; Quiñones, Octavio A; Johnson, Peter F

    2015-12-14

    The integrated stress response (ISR) controls cellular adaptations to nutrient deprivation, redox imbalances, and endoplasmic reticulum (ER) stress. ISR genes are upregulated in stressed cells, primarily by the bZIP transcription factor ATF4 through its recruitment to cis-regulatory C/EBP:ATF response elements (CAREs) together with a dimeric partner of uncertain identity. Here, we show that C/EBPγ:ATF4 heterodimers, but not C/EBPβ:ATF4 dimers, are the predominant CARE-binding species in stressed cells. C/EBPγ and ATF4 associate with genomic CAREs in a mutually dependent manner and coregulate many ISR genes. In contrast, the C/EBP family members C/EBPβ and C/EBP homologous protein (CHOP) were largely dispensable for induction of stress genes. Cebpg(-/-) mouse embryonic fibroblasts (MEFs) proliferate poorly and exhibit oxidative stress due to reduced glutathione levels and impaired expression of several glutathione biosynthesis pathway genes. Cebpg(-/-) mice (C57BL/6 background) display reduced body size and microphthalmia, similar to ATF4-null animals. In addition, C/EBPγ-deficient newborns die from atelectasis and respiratory failure, which can be mitigated by in utero exposure to the antioxidant, N-acetyl-cysteine. Cebpg(-/-) mice on a mixed strain background showed improved viability but, upon aging, developed significantly fewer malignant solid tumors than WT animals. Our findings identify C/EBPγ as a novel antioxidant regulator and an obligatory ATF4 partner that controls redox homeostasis in normal and cancerous cells.

  9. The CK1 family: contribution to cellular stress response and its role in carcinogenesis

    Directory of Open Access Journals (Sweden)

    Uwe eKnippschild

    2014-05-01

    Full Text Available Members of the highly conserved and ubiquitously expressed pleiotropic CK1 family play major regulatory roles in many cellular processes including DNA-processing and repair, proliferation, cytoskeleton dynamics, vesicular trafficking, apoptosis, and cell differentiation. As a consequence of cellular stress conditions, interaction of CK1 with the mitotic spindle is manifold increased pointing to regulatory functions at the mitotic checkpoint. Furthermore, CK1 is able to alter the activity of key regulatory proteins and signal integration molecules and is tightly connected to the regulation of β-catenin, p53- and MDM2-specific functions and degradation. Considering the importance of CK1 for accurate cell division and regulation of tumor suppressor functions it is not surprising that mutations and alterations in the expression and/or activity of CK1 isoforms are often detected in various tumor entities including cancer of the kidney, choriocarcinomas, breast carcinomas, oral cancer, adenocarcinomas of the pancreas, and ovarian cancer. Therefore, effort has enormously increased (i to understand the regulation of CK1 and its involvement in tumorigenesis- and tumor progression-related signal transduction pathways and (ii to develop CK1-specific inhibitors for the use in personalized therapy concepts. In this review we summarize the current knowledge regarding the regulation, functions, and interactions of CK1 family members with cellular proteins playing central roles in cellular stress-responses and carcinogenesis.

  10. Cellular adaptive response to glutathione depletion modulates endothelial dysfunction triggered by TNF-α.

    Science.gov (United States)

    Speciale, Antonio; Anwar, Sirajudheen; Ricciardi, Elisabetta; Chirafisi, Joselita; Saija, Antonella; Cimino, Francesco

    2011-12-15

    Several interrelated cellular signaling molecules are involved in modulating adaptive compensatory changes elicited by low exposures to toxins and other stressors. The most prominent example of signaling pathway typically involved in this adaptive stress response, is represented by the activation of a redox-sensitive gene regulatory network mediated by the NF-E2-related factor-2 (Nrf2) which is intimately involved in mediating the Antioxidant Responsive Element (ARE)-driven response to oxidative stress and xenobiotics. We investigated if Nrf2 pathway activation following intracellular glutathione depletion through buthionine sulfoximine (BSO) exposure, might be able to alter the response to TNF-α, a proinflammatory cytokine, in cultured human umbilical vein endothelial cells. Herein, we revealed that such a change in the cellular redox status is able to reduce TNF-α induced endothelial activation (as shown by a decreased gene expression of adhesion molecules) by activating an adaptive response mediated by an increased Nrf2 nuclear translocation and overexpression of the ARE genes HO-1 and NQO-1. Furthermore, we have demonstrated the involvement of ERK1/2 kinases in Nrf2 nuclear translocation activated by BSO-induced glutathione depletion. The coordinate induction of endogenous cytoprotective proteins through adaptive activation of Nrf2 pathway is a field of great interest for potential application in prevention and therapy of inflammatory diseases such as atherosclerosis. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  11. A Review on Hemeoxygenase-2: Focus on Cellular Protection and Oxygen Response

    Directory of Open Access Journals (Sweden)

    Jorge Muñoz-Sánchez

    2014-01-01

    Full Text Available Hemeoxygenase (HO system is responsible for cellular heme degradation to biliverdin, iron, and carbon monoxide. Two isoforms have been reported to date. Homologous HO-1 and HO-2 are microsomal proteins with more than 45% residue identity, share a similar fold and catalyze the same reaction. However, important differences between isoforms also exist. HO-1 isoform has been extensively studied mainly by its ability to respond to cellular stresses such as hemin, nitric oxide donors, oxidative damage, hypoxia, hyperthermia, and heavy metals, between others. On the contrary, due to its apparently constitutive nature, HO-2 has been less studied. Nevertheless, its abundance in tissues such as testis, endothelial cells, and particularly in brain, has pointed the relevance of HO-2 function. HO-2 presents particular characteristics that made it a unique protein in the HO system. Since attractive results on HO-2 have been arisen in later years, we focused this review in the second isoform. We summarize information on gene description, protein structure, and catalytic activity of HO-2 and particular facts such as its cellular impact and activity regulation. Finally, we call attention on the role of HO-2 in oxygen sensing, discussing proposed hypothesis on heme binding motifs and redox/thiol switches that participate in oxygen sensing as well as evidences of HO-2 response to hypoxia.

  12. [Regulatory role of mechanical stress response in cellular function: development of new drugs and tissue engineering].

    Science.gov (United States)

    Momose, Kazutaka; Matsuda, Takehisa; Oike, Masahiro; Obara, Kazuo; Laher, Ismail; Sugiura, Seiryo; Ohata, Hisayuki; Nakayama, Koichi

    2003-02-01

    The investigation of mechanotransduction in the cardiovascular system is essentially important for elucidating the cellular and molecular mechanisms involved in not only the maintenance of hemodynamic homeostasis but also etiology of cardiovascular diseases including arteriosclerosis. The present review summarizes the latest research performed by six academic groups, and presented at the 75th Annual Meeting of the Japanese Pharmacological Society. Technology of cellular biomechanics is also required for research and clinical application of a vascular hybrid tissue responding to pulsatile stress. 1) Vascular tissue engineering: Design of pulsatile stress-responsive scaffold and in vivo vascular wall reconstruction (T. Matsuda); 2) Cellular mechanisms of mechanosensitive calcium transients in vascular endothelium (M. Oike et al.); 3) Cross-talk of stimulation with fluid flow and lysophosphatidic acid in vascular endothelial cells (K. Momose et al.); 4) Mechanotransduction of vascular smooth muscles: Rate-dependent stretch-induced protein phosphorylations and contractile activation (K. Obara et al.); 5) Lipid mediators in vascular myogenic tone (I. Laher et al.); and 6) Caldiomyocyte regulates its mechanical output in response to mechanical load (S. Sugiura et al.).

  13. The cellular magnetic response and biocompatibility of biogenic zinc- and cobalt-doped magnetite nanoparticles

    Science.gov (United States)

    Moise, Sandhya; Céspedes, Eva; Soukup, Dalibor; Byrne, James M.; El Haj, Alicia J.; Telling, Neil D.

    2017-01-01

    The magnetic moment and anisotropy of magnetite nanoparticles can be optimised by doping with transition metal cations, enabling their properties to be tuned for different biomedical applications. In this study, we assessed the suitability of bacterially synthesized zinc- and cobalt-doped magnetite nanoparticles for biomedical applications. To do this we measured cellular viability and activity in primary human bone marrow-derived mesenchymal stem cells and human osteosarcoma-derived cells. Using AC susceptibility we studied doping induced changes in the magnetic response of the nanoparticles both as stable aqueous suspensions and when associated with cells. Our findings show that the magnetic response of the particles was altered after cellular interaction with a reduction in their mobility. In particular, the strongest AC susceptibility signal measured in vitro was from cells containing high-moment zinc-doped particles, whilst no signal was observed in cells containing the high-anisotropy cobalt-doped particles. For both particle types we found that the moderate dopant levels required for optimum magnetic properties did not alter their cytotoxicity or affect osteogenic differentiation of the stem cells. Thus, despite the known cytotoxicity of cobalt and zinc ions, these results suggest that iron oxide nanoparticles can be doped to sufficiently tailor their magnetic properties without compromising cellular biocompatibility.

  14. The use and analysis of multiple responses in multicompartment cellular systems.

    Science.gov (United States)

    Allen, D J; Reimers, H J; Feuerstein, I A; Mustard, J F

    1975-12-01

    Within multicompartment cellular systems in the steady state the distrubution of tracer as a function of time is described by sums of exponentials. A design for data collection and analysis is set forward to deal with the problems of lumping and ill-conditioning inherent in such a mathematical description. This design requires the provision of multiple responses and can be analyzed by a Bayesian multivariate technique. Although only one response may be capable of completely characterizing the system, there is much to be gained from additional responses in terms of precision in parameter estimation. A time series is used to account for autocorrelated error in the responses. The design is compared to other least squares approaches and is demonstrated in an investigation of the transport and storage of serotonin in blood platelets. The kinetic parameters describing serotinin movement are estimated and their joint confidnece regions plotted.

  15. Interactions between glucocorticoid treatment and cis-regulatory polymorphisms contribute to cellular response phenotypes.

    Directory of Open Access Journals (Sweden)

    Joseph C Maranville

    2011-07-01

    Full Text Available Glucocorticoids (GCs mediate physiological responses to environmental stress and are commonly used as pharmaceuticals. GCs act primarily through the GC receptor (GR, a transcription factor. Despite their clear biomedical importance, little is known about the genetic architecture of variation in GC response. Here we provide an initial assessment of variability in the cellular response to GC treatment by profiling gene expression and protein secretion in 114 EBV-transformed B lymphocytes of African and European ancestry. We found that genetic variation affects the response of nearby genes and exhibits distinctive patterns of genotype-treatment interactions, with genotypic effects evident in either only GC-treated or only control-treated conditions. Using a novel statistical framework, we identified interactions that influence the expression of 26 genes known to play central roles in GC-related pathways (e.g. NQO1, AIRE, and SGK1 and that influence the secretion of IL6.

  16. Modeling of time-dose-LET effects in the cellular response to radiation

    Energy Technology Data Exchange (ETDEWEB)

    Herr, Lisa Antje

    2015-07-20

    This work is dedicated to the elucidation of time-dose- and if applicable linear energy transfer (LET) effects in the cellular response to ion or photon radiation. In particular, the common concept of the Local Effect Model (LEM) and the Giant Loop Binary Lesion (GLOBLE) model, which explains cell survival probabilities on the hand of clustering of double-strand breaks (DSB) in micrometer-sized sub-structural units of the DNA, was investigated with regard to temporal aspects. In previous studies with the LEM and GLOBLE model, it has been demonstrated that the definition of two lesion classes, characterized by single or multiple DSB in a DNA giant loop, with two repair fidelities is adequate to comprehensively describe the dose dependence of the cellular response to instantaneous photon irradiation or ion irradiation with varying LET. Furthermore, with the GLOBLE model for photon radiation, it has been shown that the assignment of two repair time scales to the two lesion classes allows to adequately reproduce time-dose effects after photon irradiation with an arbitrary constant dose-rate. In this work, the results of four projects that strengthen the mechanistic consistency and the practical applicability of the LEM and GLOBLE model will be presented. First, it was found that the GLOBLE model is applicable to describe time-dose effects in the cellular response to two split photon doses and in the occurrence of deterministic radiation effects. Second, in a comparison of ten models for the temporal course of DSB rejoining, it was revealed that a bi-exponential approach, as suggested by the LEM and GLOBLE model, finds a relatively large support by 61 experimental data sets. Third, in a comparison of four kinetic photon cell survival models that was based on fits to 13 dose-rate experiments, it was shown that the GLOBLE model performs well with respect to e.g. accuracy, parsimony, reliability and other factors that characterize a good approach. Last but not least, the

  17. Pteromalus puparum venom impairs host cellular immune responses by decreasing expression of its scavenger receptor gene

    Science.gov (United States)

    Insect host/parasitoid interactions are co-evolved systems in which host defenses are balanced by parasitoid mechanisms to disable or hide from host immune effectors. Although there is a rich literature on these systems, parasitoid immune-disabling mechanisms have not been fully elucidated. Here we ...

  18. Impaired cellular immune response in harbour seals (Phoca vitulina) feeding on environmentally contaminated herring.

    NARCIS (Netherlands)

    R.L. de Swart (Rik); P.S. Ross (Peter); H.H. Timmerman (Helga); H.W. Vos (Helma); P.J.H. Reijnders; J.G. Vos (Joseph); A.D.M.E. Osterhaus (Albert)

    1995-01-01

    textabstractIn a 2.5-year immunotoxicological study, two groups of captive harbour seals (Phoca vitulina) were fed herring from the heavily polluted Baltic Sea or from the relatively uncontaminated Atlantic Ocean. Blood samples were collected at regular intervals, and functional immunological parame

  19. Impaired Cytokine Responses to Epstein-Barr Virus Antigens in Systemic Lupus Erythematosus Patients

    DEFF Research Database (Denmark)

    Draborg, Anette Holck; Sandhu, Noreen; Larsen, Nanna

    2016-01-01

    We analyzed cytokine responses against latent and lytic Epstein-Barr virus (EBV) antigens in systemic lupus erythematosus (SLE) patients and healthy controls (HCs) to obtain an overview of the distinctive immune regulatory response in SLE patients and to expand the previously determined impaired...

  20. Immune responses in human infections with Brugia malayi: specific cellular unresponsiveness to filarial antigens.

    Science.gov (United States)

    Piessens, W F; McGreevy, P B; Piessens, P W; McGreevy, M; Koiman, I; Saroso, J S; Dennis, D T

    1980-01-01

    We evaluated the cellular immune competence of 101 subjects living in an area of South Kalimantan (Borneo) where Malayan filariasis is endemic. All patients with elephantiasis but none with other clinical stages of filariasis reacted with adult worm antigens. The majority of subjects without clinical or parasitological evidence of filariasis and approximately one-half of those with amicrofilaremic filariasis reacted with microfilarial antigens. In contrast, most patients with patent microfilaremia did not respond to microfilarial antigens. The in vitro reactivity of all patient categories to nonparasite antigens was similar to that of the distant control group. These results indicate that patent microfilaremia is associated with a state of specific cellular immune unresponsiveness and are consistent with the current hypothesis that the various clinical manifestations of filariasis result from different types of immune responses to distinct antigens associated with different developmental stages of filarial worms. PMID:7350196

  1. On the effects of geometry, defects, and material asymmetry on the mechanical response of shape memory alloy cellular lattice structures

    Science.gov (United States)

    Karamooz Ravari, M. R.; Nasr Esfahani, S.; Taheri Andani, M.; Kadkhodaei, M.; Ghaei, A.; Karaca, H.; Elahinia, M.

    2016-02-01

    Shape memory alloy (such as NiTi) cellular lattice structures are a new class of advanced materials with many potential applications. The cost of fabrication of these structures however is high. It is therefore necessary to develop modeling methods to predict the functional behavior of these alloys before fabrication. The main aim of the present study is to assess the effects of geometry, microstructural imperfections and material asymmetric response of dense shape memory alloys on the mechanical response of cellular structures. To this end, several cellular and dense NiTi samples are fabricated using a selective laser melting process. Both cellular and dense specimens were tested in compression in order to obtain their stress-strain response. For modeling purposes, a three -dimensional (3D) constitutive model based on microplane theory which is able to describe the material asymmetry was employed. Five finite element models based on unit cell and multi-cell methods were generated to predict the mechanical response of cellular lattices. The results show the considerable effects of the microstructural imperfections on the mechanical response of the cellular lattice structures. The asymmetric material response of the bulk material also affects the mechanical response of the corresponding cellular structure.

  2. Electrolyte effects on the surface chemistry and cellular response of anodized titanium

    Energy Technology Data Exchange (ETDEWEB)

    Ohtsu, Naofumi, E-mail: nohtsu@mail.kitami-it.ac.jp [Instrumental Analysis Center, Kitami Institute of Technology, 165 Koen-cho, Kitami, Hokkaido 090-8507 (Japan); Kozuka, Taro; Hirano, Mitsuhiro [Instrumental Analysis Center, Kitami Institute of Technology, 165 Koen-cho, Kitami, Hokkaido 090-8507 (Japan); Arai, Hirofumi [Department of Biotechnology and Environmental Chemistry, Kitami Institute of Technology, Kitami, Hokkaido 090-8507 (Japan)

    2015-09-15

    Highlights: • Ti samples were anodized using various electrolytes. • Anodization decreased carbon adsorption, improving hydrophilicity. • Improved hydrophilicity led to improved cellular attachment. • Only one electrolyte showed any heteroatom incorporation into the TiO{sub 2} layer. • Choice of electrolyte played no role on the effects of anodization. - Abstract: Anodic oxidation of titanium (Ti) material is used to enhance biocompatibility, yet the effects of various electrolytes on surface characteristics and cellular behavior have not been completely elucidated. To investigate this topic, oxide layers were produced on Ti substrates by anodizing them in aqueous electrolytes of (NH{sub 4}){sub 2}O·5B{sub 2}O{sub 3}, (NH{sub 4}){sub 2}SO{sub 4}, or (NH{sub 4}){sub 3}PO{sub 4}, after which their surface characteristics and cellular responses were examined. Overall, no surface differences between the electrolytes were visually observed. X-ray photoelectron spectroscopy (XPS) revealed that the anodized surfaces are composed of titanium dioxide (TiO{sub 2}), while incorporation from electrolyte was only observed for (NH{sub 4}){sub 3}PO{sub 4}. Surface adsorption of carbon contaminants during sterilization was suppressed by anodization, leading to lower water contact angles. The attachment of MC3T3-E1 osteoblast-like cells was also improved by anodization, as evidenced by visibly enlarged pseudopods. This improved attachment performance is likely due to TiO{sub 2} formation. Overall, electrolyte selection showed no effect on either surface chemistry or cellular response of Ti materials.

  3. Transition between immune and disease states in a cellular automaton model of clonal immune response

    CERN Document Server

    Bezzi, M; Ruffo, S; Seiden, P E; Bezzi, Michele; Celada, Franco; Ruffo, Stefano; Seiden, Philip E.

    1997-01-01

    In this paper we extend the Celada-Seiden (CS) model of the humoral immune response to include infectious virus and cytotoxic T lymphocytes (cellular response). The response of the system to virus involves a competition between the ability of the virus to kill the host cells and the host's ability to eliminate the virus. We find two basins of attraction in the dynamics of this system, one is identified with disease and the other with the immune state. There is also an oscillating state that exists on the border of these two stable states. Fluctuations in the population of virus or antibody can end the oscillation and drive the system into one of the stable states. The introduction of mechanisms of cross-regulation between the two responses can bias the system towards one of them. We also study a mean field model, based on coupled maps, to investigate virus-like infections. This simple model reproduces the attractors for average populations observed in the cellular automaton. All the dynamical behavior connect...

  4. Distinctive behavioral and cellular responses to fluoxetine in the mouse model for Fragile X syndrome

    Directory of Open Access Journals (Sweden)

    Marko eUutela

    2014-05-01

    Full Text Available Fluoxetine is used as a therapeutic agent for autism spectrum disorder (ASD, including Fragile X syndrome (FXS. The treatment often associates with disruptive behaviors such as agitation and disinhibited behaviors in FXS. To identify mechanisms that increase the risk to poor treatment outcome, we investigated the behavioral and cellular effects of fluoxetine on adult Fmr1 knockout (KO mice, a mouse model for FXS. We found that fluoxetine reduced anxiety-like behavior of both wild type and Fmr1 KO mice seen as shortened latency to enter the center area in the open field test. In Fmr1 KO mice, fluoxetine normalized locomotor hyperactivity but abnormally increased exploratory activity. Reduced Brain-derived neurotrophic factor (BDNF and increased TrkB receptor expression levels in the hippocampus of Fmr1 KO mice associated with inappropriate coping responses under stressful condition and abolished antidepressant activity of fluoxetine. Fluoxetine response in the cell proliferation was also missing in the hippocampus of Fmr1 KO mice when compared with wild type controls. The postnatal expression of serotonin transporter was reduced in the thalamic nuclei of Fmr1 KO mice during the time of transient innervation of somatosensory neurons suggesting that developmental changes of serotonin transporter (SERT expression were involved in the differential cellular and behavioral responses to fluoxetine in wild type and Fmr1 mice. The results indicate that changes of BDNF/TrkB signaling contribute to differential behavioral responses to fluoxetine among individuals with ASD.

  5. Quantitative high content imaging of cellular adaptive stress response pathways in toxicity for chemical safety assessment.

    Science.gov (United States)

    Wink, Steven; Hiemstra, Steven; Huppelschoten, Suzanna; Danen, Erik; Niemeijer, Marije; Hendriks, Giel; Vrieling, Harry; Herpers, Bram; van de Water, Bob

    2014-03-17

    Over the past decade, major leaps forward have been made on the mechanistic understanding and identification of adaptive stress response landscapes underlying toxic insult using transcriptomics approaches. However, for predictive purposes of adverse outcome several major limitations in these approaches exist. First, the limited number of samples that can be analyzed reduces the in depth analysis of concentration-time course relationships for toxic stress responses. Second these transcriptomics analysis have been based on the whole cell population, thereby inevitably preventing single cell analysis. Third, transcriptomics is based on the transcript level, totally ignoring (post)translational regulation. We believe these limitations are circumvented with the application of high content analysis of relevant toxicant-induced adaptive stress signaling pathways using bacterial artificial chromosome (BAC) green fluorescent protein (GFP) reporter cell-based assays. The goal is to establish a platform that incorporates all adaptive stress pathways that are relevant for toxicity, with a focus on drug-induced liver injury. In addition, cellular stress responses typically follow cell perturbations at the subcellular organelle level. Therefore, we complement our reporter line panel with reporters for specific organelle morphometry and function. Here, we review the approaches of high content imaging of cellular adaptive stress responses to chemicals and the application in the mechanistic understanding and prediction of chemical toxicity at a systems toxicology level.

  6. Signaling pathways implicated in the cellular innate immune responses of Drosophila

    Directory of Open Access Journals (Sweden)

    AJ Nappi

    2004-06-01

    Full Text Available The phylogenetically conserved innate immune systems of insects and other invertebrates employblood cells (hemocytes that are functionally reminiscent of vertebrate macrophages, attesting to theimportance of phagocytosis and other cell-mediated responses in eliminating various pathogens. Receptorligandbinding activates signaling cascades that promote collaborative cellular interactions and theproduction of pathogen-specific cytotoxic responses. Numerous comparative genetic and molecularstudies have shown the cytotoxic effector responses made by cells of the innate immune system to beevolutionarily conserved. Comparative analyses of genomic sequences provide convincing evidence thatmany of the biochemical processes manifested by immune-activated hemocytes are similar to thosemade by activated vertebrate macrophages. Included in this genomic repertoire are enzymes associatedwith reactive intermediates of oxygen and nitrogen, cellular redox homeostasis, and apoptosis, thesynthesis of extracellular matrix, cell adhesion and pattern recognition molecules. Surprisingly, little isknown of the types of cytotoxic molecules produced by invertebrate hemocytes, and the signaling andtranscriptional events associated with their collaborative interactions when engaging pathogens andparasites. This review examines certain aspects of the blood cell-mediated defense responses ofDrosophila, and some of the signaling pathways that have been implicated in hemocyte activation,differentiation, and the regulation of hematopoiesis.

  7. Fructose-1,6-bisphosphatase mediates cellular responses to DNA damage and aging in Saccharomyces cerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Kitanovic, Ana [Institut fuer Pharmazie und Molekulare Biotechnologie, Ruprecht-Karls-Universitaet Heidelberg, Im Neuenheimer Feld 364, D-69120 Heidelberg (Germany); Woelfl, Stefan [Institut fuer Pharmazie und Molekulare Biotechnologie, Ruprecht-Karls-Universitaet Heidelberg, Im Neuenheimer Feld 364, D-69120 Heidelberg (Germany)]. E-mail: wolfl@uni-hd.de

    2006-02-22

    Response to DNA damage, lack of nutrients and other stress conditions is an essential property of living systems. The coordinate response includes DNA damage repair, activation of alternate biochemical pathways, adjustment of cellular proliferation and cell cycle progression as well as drastic measures like cellular suicide which prevents proliferation of severely damaged cells. Investigating the transcriptional response of Saccharomyces cerevisiae to low doses of the alkylating agent methylmethane sulfonate (MMS) we observed induction of genes involved in glucose metabolism. RT-PCR analysis showed that the expression of the key enzyme in gluconeogenesis fructose-1,6-bisphosphatase (FBP1) was clearly up-regulated by MMS in glucose-rich medium. Interestingly, deletion of FBP1 led to reduced sensitivity to MMS, but not to other DNA-damaging agents, such as 4-NQO or phleomycin. Reintroduction of FBP1 in the knockout restored the wild-type phenotype while overexpression increased MMS sensitivity of wild-type, shortened life span and increased induction of RNR2 after treatment with MMS. Deletion of FBP1 reduced production of reactive oxygen species (ROS) in response to MMS treatment and in untreated aged cells, and increased the amount of cells able to propagate and to form colonies, but had no influence on the genotoxic effect of MMS. Our results indicate that FBP1 influences the connection between DNA damage, aging and oxidative stress through either direct signalling or an intricate adaptation in energy metabolism.0.

  8. A candidate DNA vaccine elicits HCV specific humoral and cellular immune responses

    Institute of Scientific and Technical Information of China (English)

    Li-Xin Zhu; Jing Liu; Ye Ye; You-Hua Xie; Yu-Ying Kong; Guang-Di Li; Yuan Wang

    2004-01-01

    AIM: To investigate the immunogenicity of candidate DNA vaccine against hepatitis C virus (HCV) delivered by two plasmids expressing HCV envelope protein 1 (E1) and envelope protein 2 (E2) antigens respectively and to study the effect of CpG adjuvant on this candidate vaccine.METHODS: Recombinant plasmids expressing HCV E1 and E2 antigens respectively were used to simultaneously inoculate mice with or without CpG adjuvant. Antisera were then collected and titers of anti-HCV antibodies were analyzed by ELISA. One month after the last injection, animals were sacrificed to prepare single-cell suspension of splenocytes.These cells were subjected to HCVantigen specific proliferation assays and cytokine secretion assays to evaluate the cellular immune responses of the vaccinated animals.RESULTS: Antibody responses to HCV E1 and E2 antigens were detected in vaccinated animals. Animals receiving CpG adjuvant had slightly lower titers of anti-HCV antibodies in the sera, while the splenocytes from these animals showed higher HCV-antigen specific proliferation. Analysis of cytokine secretion from the splenocytes was consistent with the above results. While no antigen-specific IL-4 secretion was detected for all vaccinated animals, HCV antigen-specific INF-γ secretion was detected for the splenocytes of vaccinated animals. CpG adjuvant enhanced the secretion of INF-γ but did not change the profile of IL-4 secretion.CONCLUSION: Vaccination of mice with plasmids encoding HCV E1 and E2 antigens induces humoral and cellular immune responses. CpG adjuvant significantly enhances the cellular immune response.

  9. Hfe deficiency impairs pulmonary neutrophil recruitment in response to inflammation.

    Directory of Open Access Journals (Sweden)

    Karolina Benesova

    Full Text Available Regulation of iron homeostasis and the inflammatory response are tightly linked to protect the host from infection. Here we investigate how imbalanced systemic iron homeostasis in a murine disease model of hereditary hemochromatosis (Hfe(-/- mice affects the inflammatory responses of the lung. We induced acute pulmonary inflammation in Hfe(-/- and wild-type mice by intratracheal instillation of 20 µg of lipopolysaccharide (LPS and analyzed local and systemic inflammatory responses and iron-related parameters. We show that in Hfe(-/- mice neutrophil recruitment to the bronchoalveolar space is attenuated compared to wild-type mice although circulating neutrophil numbers in the bloodstream were elevated to similar levels in Hfe(-/- and wild-type mice. The underlying molecular mechanisms are likely multifactorial and include elevated systemic iron levels, alveolar macrophage iron deficiency and/or hitherto unexplored functions of Hfe in resident pulmonary cell types. As a consequence, pulmonary cytokine expression is out of balance and neutrophils fail to be recruited efficiently to the bronchoalveolar compartment, a process required to protect the host from infections. In conclusion, our findings suggest a novel role for Hfe and/or imbalanced iron homeostasis in the regulation of the inflammatory response in the lung and hereditary hemochromatosis.

  10. The role of nuclear factor κB in the cellular response to different radiation qualities

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Kristina

    2013-04-11

    Radiation is currently one of the most important limiting factors for manned space flight. During such missions, there is a constant exposure to low doses of galactic cosmic radiation and in particular high-energy heavy ions. Together this is associated with an increased cancer risk which currently cannot be sufficiently reduced by shielding. As such, cellular radiation response needs to be further studied in order to improve risk estimation and develop appropriate countermeasures. It has been shown that exposure of human cells to accelerated heavy ions, in fluences that can be reached during long-term missions, leads to activation of the Nuclear Factor κB (NF-κB) pathway. Heavy ions with a linear energy transfer (LET) of 90 to 300 keV/μm were most effective in activating NF-κB. NF-κB as an important modulating factor in the cellular radiation response could improve cellular survival after heavy ion exposure, thereby influencing the cancer risk of astronauts. The NF-κB pathway may be a potential pharmacological target in the mitigation of radiation response during space missions; such as the prevention of massive cell death after high dose irradiation (acute effects), in addition to neoplastic cell transformation during chronic low-dose exposure (late effects). The aim of this work was to examine the role of NF-κB in the cellular response to space-relevant radiation. Firstly, NF-κB activation in human embryonic kidney cells (HEK) after exposure to different radiation qualities and quantities was investigated. Key elements of different NF-κB sub-pathways were chemically inhibited to analyze their role in NF-κB activation induced by low and high LET ionizing radiation. Finally a cell line, stably transfected with a plasmid coding for a short-hairpin RNA (shRNA) for a knockdown of the NF-κB subunit RelA, was established to assess the role of RelA in the cellular response to space-relevant radiation. The knockdown was verified on several levels and the cell

  11. Classifying performance impairment in response to sleep loss using pattern recognition algorithms on single session testing.

    Science.gov (United States)

    St Hilaire, Melissa A; Sullivan, Jason P; Anderson, Clare; Cohen, Daniel A; Barger, Laura K; Lockley, Steven W; Klerman, Elizabeth B

    2013-01-01

    There is currently no "gold standard" marker of cognitive performance impairment resulting from sleep loss. We utilized pattern recognition algorithms to determine which features of data collected under controlled laboratory conditions could most reliably identify cognitive performance impairment in response to sleep loss using data from only one testing session, such as would occur in the "real world" or field conditions. A training set for testing the pattern recognition algorithms was developed using objective Psychomotor Vigilance Task (PVT) and subjective Karolinska Sleepiness Scale (KSS) data collected from laboratory studies during which subjects were sleep deprived for 26-52h. The algorithm was then tested in data from both laboratory and field experiments. The pattern recognition algorithm was able to identify performance impairment with a single testing session in individuals studied under laboratory conditions using PVT, KSS, length of time awake and time of day information with sensitivity and specificity as high as 82%. When this algorithm was tested on data collected under real-world conditions from individuals whose data were not in the training set, accuracy of predictions for individuals categorized with low performance impairment were as high as 98%. Predictions for medium and severe performance impairment were less accurate. We conclude that pattern recognition algorithms may be a promising method for identifying performance impairment in individuals using only current information about the individual's behavior. Single testing features (e.g., number of PVT lapses) with high correlation with performance impairment in the laboratory setting may not be the best indicators of performance impairment under real-world conditions. Pattern recognition algorithms should be further tested for their ability to be used in conjunction with other assessments of sleepiness in real-world conditions to quantify performance impairment in response to sleep loss.

  12. The p53 Codon 72 Polymorphism Modifies the Cellular Response to Inflammatory Challenge in the Liver.

    Science.gov (United States)

    Leu, Julia I-Ju; Murphy, Maureen E; George, Donna L

    2013-01-01

    The p53 protein is a critical stress-response mediator and signal coordinator in cellular metabolism and environmental exposure to deleterious agents. In human populations, the p53 gene contains a common single nucleotide polymorphism (SNP) affecting codon 72 that determines whether a proline (P72) or an arginine (R72) is present at this amino acid position of the polypeptide. Previous studies carried out using human populations, mouse models, and cell culture analyses have provided evidence that this amino acid difference can alter p53 functional activities, and potentially also can affect clinical presentation of disease. The clinical presentation associated with many forms of liver disease is variable, but few of the responsible underlying genetic factors or molecular pathways have been identified. The aim of the present study was to investigate whether the p53 codon 72 polymorphism influences the cellular response to hepatic stresses. A humanized p53 knock-in (Hupki) mouse model was used to address this issue. Mice expressing either the P72 or R72 normal variation of p53 were given an acute-, intermittent- or a chronic challenge, associated with exposure to lipopolysaccharide, D-galactosamine, or a high-fat diet. The results reveal that the livers of the P72 and R72 mice exhibit notable differences in inflammatory and apoptotic response to these distinct forms of stress. Interestingly the influence of this polymorphism on the response to stress is context dependent, with P72 showing increased response to liver toxins (lipopolysaccharide and D-galactosamine), but R72 showing increased response to metabolic stress (high fat diet). When taken together, these data point to the p53 codon 72 polymorphism as an important molecular mediator of events contributing to hepatic inflammation and metabolic homeostasis.

  13. Expression patterns and action analysis of genes associated with physiological responses during rat liver regeneration: Cellular immune response

    Institute of Scientific and Technical Information of China (English)

    Lian-Xing Zhang; Li-Feng Zhao; An-Shi Zhang; Xiao-Guang Chen; Cun-Shuan Xu

    2006-01-01

    AIM: To study the cellular immune response during rat liver regeneration (LR) at a transcriptional level.METHODS: Genes associated with the cellular immune response were obtained by collecting the data from databases and retrieving articles. Gene expression changes during LR were detected by rat genome 230 2.0 array.RESULTS: A total of 127 genes were found to be associated with LR. The number of initially and totally expressing genes in the initial phase of LR [0.5-4 h after partial hepatectomy (PH)], transition from G0-G1(4-6 h after PH), cell proliferation (6-66 h after PH),cell differentiation and structure-function reconstruction (66-168 h after PH) was 54, 11, 34, 3 and 54, 49, 70, 49 respectively, illustrating that the associated genes were mainly triggered at the initiation of LR, and worked at different phases. According to their expression similarity,these genes were classified into 41 up-regulated, 21 predominantly up-regulated, 41 down-regulated, 14 predominantly down-regulated, 10 similarly up-regulated and down-regulated genes, respectively. The total upand down-regulated expression times were 419 and 274,respectively, demonstrating that the expression of most genes was increased while the expression of a small number of genes was decreased. Their time relevance was classified into 14 groups, showing that the cellular physiological and biochemical activities were staggered during LR. According to the gene expression patterns,they were classified into 21 types, showing the activities were diverse and complicated during LR.CONCLUSION: Antigen processing and presentation are enhanced mainly in the forepart, prophase and anaphase of LR. T-cell activation and antigen elimination are enhanced mainly in the forepart and prophase of LR. A total of 127 genes associated with LR play an important role in cellular immunity.

  14. Capturing the dynamic nascent transcriptome during acute cellular responses: The serum response

    Directory of Open Access Journals (Sweden)

    Killeen S. Kirkconnell

    2016-06-01

    Full Text Available Dynamic regulation of gene expression via signal transduction pathways is of fundamental importance during many biological processes such as cell state transitioning, cell cycle progression and stress responses. In this study we used serum stimulation as a cell response paradigm to apply the nascent RNA Bru-seq technique in order to capture early dynamic changes in the nascent transcriptome. Our data provides an unprecedented view of the dynamics of genome-wide transcription during the first two hours of serum stimulation in human fibroblasts. While some genes showed sustained induction or repression, other genes showed transient or delayed responses. Surprisingly, the dynamic patterns of induction and suppression of response genes showed a high degree of similarity, suggesting that these opposite outcomes are triggered by a common set of signals. As expected, early response genes such as those encoding components of the AP-1 transcription factor and those involved in the circadian clock were immediately but transiently induced. Surprisingly, transcription of important DNA damage response genes and histone genes were rapidly repressed. We also show that RNA polymerase II accelerates as it transcribes large genes and this was independent of whether the gene was induced or not. These results provide a unique genome-wide depiction of dynamic patterns of transcription of serum response genes and demonstrate the utility of Bru-seq to comprehensively capture rapid and dynamic changes of the nascent transcriptome.

  15. The cellular and genetic basis of olfactory responses in Caenorhabditis elegans.

    Science.gov (United States)

    Sengupta, P; Colbert, H A; Kimmel, B E; Dwyer, N; Bargmann, C I

    1993-01-01

    The small soil nematode Caenorhabditis elegans has only 302 neurons in its entire nervous system, so it is possible to analyse the functions of individual neurons in the animal's behaviour. We are using behavioural, cellular and genetic analyses of chemotactic responses to find out how olfactory behaviour patterns are generated and regulated. Single chemosensory neurons in C. elegans can recognize several different attractive odorants that are distinguished by the animal. Distinct sets of chemosensory neurons detect high and low concentrations of a single odorant. Odorant responses adapt after prolonged exposure to an odorant; this adaptation is odorant specific and reversible. Mutants with defects in odorant responses have been identified. Some genes appear to be necessary for the development or function of particular kinds of sensory neurons. Other genes have effects that suggest that they participate in odorant reception or signal transduction.

  16. Cellular immune response of humans to the circumsporozoite protein of Plasmodium vivax

    Directory of Open Access Journals (Sweden)

    Mauricio M. Rodrigues

    1991-06-01

    Full Text Available The cellular immune response to the circumsporozoite (CS protein of plasmodium vivax of individuals from malaria-endemic areas of Brazil was studied. We examined the in vitro proliferative response of the peripheral blood mononuclear cells (PBMC of 22 individuals when stimulated with a CS recombinant protein (rPvCS-2 and two other synthetic peptides based on the sequenceof the P. vivax CS protein. Seven of the individuals from malaria-endemic area displayed an antigen specific in vitro proliferative responseto the recombinant protein PvCS-2 and one out of 6, proliferative response to the peptide 308-320. In contrast, none of the individuals displayed a proliferative reponse when stimulated with the D/A peptide which represent some of the repeated units present in this CS protein. Our study, therefore, provides evidence for the presence, withinthe major surface antigen of P. vivax sporozoites, of epitopes capble to induce proliferation of human PBMC.

  17. Cellular and biomolecular responses of human ovarian cancer cells to cytostatic dinuclear platinum(II) complexes.

    Science.gov (United States)

    Lin, Miaoxin; Wang, Xiaoyong; Zhu, Jianhui; Fan, Damin; Zhang, Yangmiao; Zhang, Junfeng; Guo, Zijian

    2011-03-01

    Polynuclear platinum(II) complexes represent a class of potential anticancer agents that have shown promising pharmacological properties in preclinical studies. The nature of cellular responses induced by these complexes, however, is poorly understood. In this research, the cellular responses of human ovarian cancer COC1 cells to dinuclear platinum(II) complexes {[cis-Pt(NH₃)₂Cl]₂L¹}(NO₃)₂ (1) and {[cis-Pt(NH₃)₂Cl]₂L²}(NO₃)₂ (2) (L¹ = α,α'-diamino-p-xylene, L² = 4,4'-methylenedianiline) has been studied using cisplatin as a reference. The effect of platinum complexes on the proliferation, death mode, mitochondrial membrane potential, and cell cycle progression has been examined by MTT assay and flow cytometry. The activation of cell cycle checkpoint kinases (CHK1/2), extracellular signal-regulated kinases (ERK1/2), and p38 mitogen-activated protein kinase (p38 MAPK) of the cells by the complexes has also been analyzed using phospho-specific flow cytometry. Complex 1 is more cytotoxic than complex 2 and cisplatin at most concentrations; complex 2 and cisplatin are comparably cytotoxic. These complexes kill the cells through an apoptotic or apoptosis-like pathway characterized by exposure of phosphatidylserine and dissipation of mitochondrial membrane potential. Complex 1 shows the strongest inductive effect on the morphological changes of the cells, followed by cisplatin and complex 2. Complexes 1 and 2 arrest the cell cycle in G2 or M phase, while cisplatin arrests the cell cycle in S phase. The influence of these complexes on CHK1/2, ERK1/2, and p38 MAPK varies with the dose of the drugs or reaction time. Activation of phospho-ERK1/2 and phospho-p38 MAPK by these complexes is closely related to the cytostatic activity. The results demonstrate that dinuclear platinum(II) complexes can induce some cellular responses different from those caused by cisplatin.

  18. Psychedelics Recruit Multiple Cellular Types and Produce Complex Transcriptional Responses Within the Brain.

    Science.gov (United States)

    Martin, David A; Nichols, Charles D

    2016-09-01

    There has recently been a resurgence of interest in psychedelics, substances that profoundly alter perception and cognition and have recently demonstrated therapeutic efficacy to treat anxiety, depression, and addiction in the clinic. The receptor mechanisms that drive their molecular and behavioral effects involve activation of cortical serotonin 5-HT2A receptors, but the responses of specific cellular populations remain unknown. Here, we provide evidence that a small subset of 5-HT2A-expressing excitatory neurons is directly activated by psychedelics and subsequently recruits other select cell types including subpopulations of inhibitory somatostatin and parvalbumin GABAergic interneurons, as well as astrocytes, to produce distinct and regional responses. To gather data regarding the response of specific neuronal populations, we developed methodology for fluorescence-activated cell sorting (FACS) to segregate and enrich specific cellular subtypes in the brain. These methods allow for robust neuronal sorting based on cytoplasmic epitopes followed by downstream nucleic acid analysis, expanding the utility of FACS in neuroscience research.

  19. Psychedelics Recruit Multiple Cellular Types and Produce Complex Transcriptional Responses Within the Brain

    Directory of Open Access Journals (Sweden)

    David A. Martin

    2016-09-01

    Full Text Available There has recently been a resurgence of interest in psychedelics, substances that profoundly alter perception and cognition and have recently demonstrated therapeutic efficacy to treat anxiety, depression, and addiction in the clinic. The receptor mechanisms that drive their molecular and behavioral effects involve activation of cortical serotonin 5-HT2A receptors, but the responses of specific cellular populations remain unknown. Here, we provide evidence that a small subset of 5-HT2A-expressing excitatory neurons is directly activated by psychedelics and subsequently recruits other select cell types including subpopulations of inhibitory somatostatin and parvalbumin GABAergic interneurons, as well as astrocytes, to produce distinct and regional responses. To gather data regarding the response of specific neuronal populations, we developed methodology for fluorescence-activated cell sorting (FACS to segregate and enrich specific cellular subtypes in the brain. These methods allow for robust neuronal sorting based on cytoplasmic epitopes followed by downstream nucleic acid analysis, expanding the utility of FACS in neuroscience research.

  20. Immunostimulating effect of aqueous extract of Amphypterygium adstringens on immune cellular response in immunosuppressed mice.

    Science.gov (United States)

    Ramírez-León, Adriana; Barajas-Martinez, Héctor; Flores-Torales, Edgardo; Orozco-Barocio, Arturo

    2012-01-01

    Amphypterygium adstringens is a Mexican tree known as cuachalalate whose bark is habitually used for the treatment of fresh wounds, gastric ulcers, gastrointestinal cancer and various inflammatory conditions. The aim of this study was to evaluate the immunostimulant effect of the aqueous extract of A. adstringens on immune cellular response in immunosuppressed mice. An aqueous extract from the bark of cuachalalate was administered into BALB/c mice for 10 days. We assessed their immunostimmulant activity on cellular immune response by Delayed Type Hypersensitivity Response (DHT) to dinitrofluorobencene (DNFB) and by MTT assay. L5178Y lymphoma was used as immunossuppression model. An increase in DHT was observed after treatment with 10 and 100 mg/kg of the aqueous extract from A. adstringens oral treatment in lymphoma bearing mice. Splenocyte proliferation rate was significantly increased (2.5 time) in immunosuppresed mice treated with 10 mg/kg oral treatment compared with group that received vehicle only. The present study showed for the first time the aqueous extract from A. adstringens as a positive immunostimulant agent in lymphoma bearing mice and we demonstrated evidence to support the traditionally use of cuachalalate in conditions in which the immune system is depressed.

  1. Differential Cellular Responses to Hedgehog Signalling in Vertebrates—What is the Role of Competence?

    Directory of Open Access Journals (Sweden)

    Clemens Kiecker

    2016-12-01

    Full Text Available A surprisingly small number of signalling pathways generate a plethora of cellular responses ranging from the acquisition of multiple cell fates to proliferation, differentiation, morphogenesis and cell death. These diverse responses may be due to the dose-dependent activities of signalling factors, or to intrinsic differences in the response of cells to a given signal—a phenomenon called differential cellular competence. In this review, we focus on temporal and spatial differences in competence for Hedgehog (HH signalling, a signalling pathway that is reiteratively employed in embryos and adult organisms. We discuss the upstream signals and mechanisms that may establish differential competence for HHs in a range of different tissues. We argue that the changing competence for HH signalling provides a four-dimensional framework for the interpretation of the signal that is essential for the emergence of functional anatomy. A number of diseases—including several types of cancer—are caused by malfunctions of the HH pathway. A better understanding of what provides differential competence for this signal may reveal HH-related disease mechanisms and equip us with more specific tools to manipulate HH signalling in the clinic.

  2. Interactions of the p53 protein family in cellular stress response in gastrointestinal tumors.

    Science.gov (United States)

    Vilgelm, Anna E; Washington, Mary K; Wei, Jinxiong; Chen, Heidi; Prassolov, Vladimir S; Zaika, Alexander I

    2010-03-01

    p53, p63, and p73 are members of the p53 protein family involved in regulation of cell cycle, apoptosis, differentiation, and other critical cellular processes. Here, we investigated the contribution of the entire p53 family in chemotherapeutic drug response in gastrointestinal tumors. Real-time PCR and immunohistochemistry revealed complexity and variability of expression profiles of the p53 protein family. Using colon and esophageal cancer cells, we found that the integral transcription activity of the entire p53 family, as measured by the reporter analysis, associated with response to drug treatment in studied cells. We also found that p53 and p73, as well as p63 and p73, bind simultaneously to the promoters of p53 target genes. Taken together, our results support the view that the p53 protein family functions as an interacting network of proteins and show that cellular responses to chemotherapeutic drug treatment are determined by the total activity of the entire p53 family rather than p53 alone.

  3. Functional recognition imaging using artificial neural networks: applications to rapid cellular identification via broadband electromechanical response

    Energy Technology Data Exchange (ETDEWEB)

    Nikiforov, M P; Guo, S; Kalinin, S V; Jesse, S [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN 37831 (United States); Reukov, V V; Thompson, G L; Vertegel, A A, E-mail: sergei2@ornl.go [Department of Bioengineering, Clemson University, Clemson, SC 29634 (United States)

    2009-10-07

    Functional recognition imaging in scanning probe microscopy (SPM) using artificial neural network identification is demonstrated. This approach utilizes statistical analysis of complex SPM responses at a single spatial location to identify the target behavior, which is reminiscent of associative thinking in the human brain, obviating the need for analytical models. We demonstrate, as an example of recognition imaging, rapid identification of cellular organisms using the difference in electromechanical activity over a broad frequency range. Single-pixel identification of model Micrococcus lysodeikticus and Pseudomonas fluorescens bacteria is achieved, demonstrating the viability of the method.

  4. Gain of Cellular Adaptation Due to Prolonged p53 Impairment Leads to Functional Switchover from p53 to p73 during DNA Damage in Acute Myeloid Leukemia Cells*

    OpenAIRE

    2010-01-01

    Tumor suppressor p53 plays the central role in regulating apoptosis in response to genotoxic stress. From an evolutionary perspective, the activity of p53 has to be backed up by other protein(s) in case of any functional impairment of this protein, to trigger DNA damage-induced apoptosis in cancer cells. We adopted multiple experimental approaches to demonstrate that in p53-impaired cancer cells, DNA damage caused accumulation of p53 paralogue p73 via Chk-1 that strongly impacted Bax expressi...

  5. Systems analysis of protein modification and cellular responses induced by electrophile stress.

    Science.gov (United States)

    Jacobs, Aaron T; Marnett, Lawrence J

    2010-05-18

    Biological electrophiles result from oxidative metabolism of exogenous compounds or endogenous cellular constituents, and they contribute to pathophysiologies such as toxicity and carcinogenicity. The chemical toxicology of electrophiles is dominated by covalent addition to intracellular nucleophiles. Reaction with DNA leads to the production of adducts that block replication or induce mutations. The chemistry and biology of electrophile-DNA reactions have been extensively studied, providing in many cases a detailed understanding of the relation between adduct structure and mutational consequences. By contrast, the linkage between protein modification and cellular response is poorly understood. In this Account, we describe our efforts to define the chemistry of protein modification and its biological consequences using lipid-derived alpha,beta-unsaturated aldehydes as model electrophiles. In our global approach, two large data sets are analyzed: one represents the identity of proteins modified over a wide range of electrophile concentrations, and the second comprises changes in gene expression observed under similar conditions. Informatics tools show theoretical connections based primarily on transcription factors hypothetically shared between the two data sets, downstream of adducted proteins and upstream of affected genes. This method highlights potential electrophile-sensitive signaling pathways and transcriptional processes for further evaluation. Peroxidation of cellular phospholipids generates a complex mixture of both membrane-bound and diffusible electrophiles. The latter include reactive species such as malondialdehyde, 4-oxononenal, and 4-hydroxynonenal (HNE). Enriching HNE-adducted proteins for proteomic analysis was a technical challenge, solved with click chemistry that generated biotin-tagged protein adducts. For this purpose, HNE analogues bearing terminal azide or alkyne functionalities were synthesized. Cellular lysates were first exposed to a

  6. Alcohol impairs predation risk response and communication in zebrafish.

    Directory of Open Access Journals (Sweden)

    Thiago Acosta Oliveira

    Full Text Available The effects of ethanol exposure on Danio rerio have been studied from the perspectives of developmental biology and behavior. However, little is known about the effects of ethanol on the prey-predator relationship and chemical communication of predation risk. Here, we showed that visual contact with a predator triggers stress axis activation in zebrafish. We also observed a typical stress response in zebrafish receiving water from these conspecifics, indicating that these fish chemically communicate predation risk. Our work is the first to demonstrate how alcohol effects this prey-predator interaction. We showed for the first time that alcohol exposure completely blocks stress axis activation in both fish seeing the predator and in fish that come in indirect contact with a predator by receiving water from these conspecifics. Together with other research results and with the translational relevance of this fish species, our data points to zebrafish as a promising animal model to study human alcoholism.

  7. Cellular and humoral immune responses to Borrelia burgdorferi antigens in patients with culture-positive early Lyme disease.

    Science.gov (United States)

    Vaz, A; Glickstein, L; Field, J A; McHugh, G; Sikand, V K; Damle, N; Steere, A C

    2001-12-01

    We determined cellular and humoral immune responses to Borrelia burgdorferi lysate and to recombinant flagellin (FlaB), OspC, and OspA in acute- and convalescent-phase samples from 39 culture-positive patients with erythema migrans and in 20 healthy control subjects. During the acute illness, a median of 4 days after the onset of erythema migrans, 51% of the patients had proliferative cellular responses and 72% had antibody responses to at least one of the borrelial antigens tested. During convalescence, at the conclusion of antibiotic therapy, 64% of the patients had proliferative cellular reactivity and 95% had antibody reactivity with at least one of the spirochetal antigens tested. In both acute- and convalescent-phase samples, cellular immune responses were found as frequently to OspA as to OspC and FlaB. Although antibody responses were also frequently seen to OspC and FlaB, only a few patients had marginal antibody reactivity with OspA. The percentage of patients with proliferative responses was similar in those with clinical evidence of localized or disseminated infection, whereas humoral reactivity was found more often in those with disseminated disease. We conclude that cellular and humoral responses to B. burgdorferi antigens are often found among patients with early Lyme disease. In contrast with the other antigens tested, cellular but not humoral reactivity was often found with OspA.

  8. Hormesis, cellular stress response and vitagenes as critical determinants in aging and longevity.

    Science.gov (United States)

    Calabrese, Vittorio; Cornelius, Carolin; Cuzzocrea, Salvatore; Iavicoli, Ivo; Rizzarelli, Enrico; Calabrese, Edward J

    2011-08-01

    Understanding mechanisms of aging and determinants of life span will help to reduce age-related morbidity and facilitate healthy aging. Average lifespan has increased over the last centuries, as a consequence of medical and environmental factors, but maximal life span remains unchanged. Extension of maximal life span is currently possible in animal models with measures such as genetic manipulations and caloric restriction (CR). CR appears to prolong life by reducing reactive oxygen species (ROS)-mediated oxidative damage. But ROS formation, which is positively implicated in cellular stress response mechanisms, is a highly regulated process controlled by a complex network of intracellular signaling pathways. By sensing the intracellular nutrient and energy status, the functional state of mitochondria, and the concentration of ROS produced in mitochondria, the longevity network regulates life span across species by co-ordinating information flow along its convergent, divergent and multiply branched signaling pathways, including vitagenes which are genes involved in preserving cellular homeostasis during stressful conditions. Vitagenes encode for heat shock proteins (Hsp) Hsp32, Hsp70, the thioredoxin and the sirtuin protein systems. Dietary antioxidants, such as carnosine, carnitines or polyphenols, have recently been demonstrated to be neuroprotective through the activation of hormetic pathways, including vitagenes. The hormetic dose-response, challenges long-standing beliefs about the nature of the dose-response in a lowdose zone, having the potential to affect significantly the design of pre-clinical studies and clinical trials as well as strategies for optimal patient dosing in the treatment of numerous diseases. Given the broad cytoprotective properties of the heat shock response there is now strong interest in discovering and developing pharmacological agents capable of inducing stress responses. In this review we discuss the most current and up to date

  9. Evaluation of cellular responses for a chimeric HBsAg-HCV core DNA vaccine in BALB/c mice

    Directory of Open Access Journals (Sweden)

    Maryam Yazdanian

    2015-01-01

    Conclusion: Fusion of HBsAg to HCVcp in the context of a DNA vaccine modality could augment Th1-oriented cellular and CTL responses toward a protective epitope, comparable to that of HCVcp (subunit HCV vaccine immunization.

  10. DNA-encapsulated magnesium phosphate nanoparticles elicit both humoral and cellular immune responses in mice

    Directory of Open Access Journals (Sweden)

    Gajadhar Bhakta

    2014-01-01

    Full Text Available The efficacy of pEGFP (plasmid expressing enhanced green fluorescent protein-encapsulated PEGylated (meaning polyethylene glycol coated magnesium phosphate nanoparticles (referred to as MgPi-pEGFP nanoparticles for the induction of immune responses was investigated in a mouse model. MgPi-pEGFP nanoparticles induced enhanced serum antibody and antigen-specific T-lymphocyte responses, as well as increased IFN-γ and IL-12 levels compared to naked pEGFP when administered via intravenous, intraperitoneal or intramuscular routes. A significant macrophage response, both in size and activity, was also observed when mice were immunized with the nanoparticle formulation. The response was highly specific for the antigen, as the increase in interaction between macrophages and lymphocytes as well as lymphocyte proliferation took place only when they were re-stimulated with recombinant green fluorescence protein (rGFP. Thus the nanoparticle formulation elicited both humoral as well as cellular responses. Cytokine profiling revealed the induction of Th-1 type responses. The results suggest DNA-encapsulated magnesium phosphate (MgPi nanoparticles may constitute a safer, more stable and cost-efficient DNA vaccine formulation.

  11. Impaired neuronal nitric oxide synthase-mediated vasodilator responses to mental stress in essential hypertension.

    Science.gov (United States)

    Khan, Sitara G; Geer, Amber; Fok, Henry W; Shabeeh, Husain; Brett, Sally E; Shah, Ajay M; Chowienczyk, Philip J

    2015-04-01

    Neuronal NO synthase (nNOS) regulates blood flow in resistance vasculature at rest and during mental stress. To investigate whether nNOS signaling is dysfunctional in essential hypertension, forearm blood flow responses to mental stress were examined in 88 subjects: 48 with essential hypertension (42±14 years; blood pressure, 141±17/85±15 mm Hg; mean±SD) and 40 normotensive controls (38±14 years; 117±13/74±9 mm Hg). A subsample of 34 subjects (17 hypertensive) participated in a single blind 2-phase crossover study, in which placebo or sildenafil 50 mg PO was administered before an intrabrachial artery infusion of the selective nNOS inhibitor S-methyl-l-thiocitrulline (SMTC, 0.05, 0.1, and 0.2 μmol/min) at rest and during mental stress. In a further subsample (n=21) with an impaired blood flow response to mental stress, responses were measured in the presence and absence of the α-adrenergic antagonist phentolamine. The blood flow response to mental stress was impaired in hypertensive compared with normotensive subjects (37±7% versus 70±8% increase over baseline; Phypertensive subjects (reduction of 40±11% versus 3.0±14%, respectively, P=0.01, between groups). Sildenafil reduced the blood flow response to stress in normotensive subjects from 89±14% to 43±14% (Phypertensive subjects. Phentolamine augmented impaired blood flow responses to mental stress from 39±8% to 67±13% (Phypertension is associated with impaired mental stress-induced nNOS-mediated vasodilator responses; this may relate to increased sympathetic outflow in hypertension. nNOS dysfunction may impair vascular homeostasis in essential hypertension and contribute to stress-induced cardiovascular events.

  12. Expression and cellular distribution of ubiquitin in response to injury in the developing spinal cord of Monodelphis domestica

    DEFF Research Database (Denmark)

    Noor, Natassya M; Møllgård, Kjeld; Wheaton, Benjamin J;

    2013-01-01

    Ubiquitin, an 8.5 kDa protein associated with the proteasome degradation pathway has been recently identified as differentially expressed in segment of cord caudal to site of injury in developing spinal cord. Here we describe ubiquitin expression and cellular distribution in spinal cord up to pos...... changes in ubiquitin expression and cellular distribution in development and response to spinal injury suggest an intricate regulatory system that modulates these responses which, when better understood, may lead to potential therapeutic targets....

  13. Molecular targets in cellular response to ionizing radiation and implications in space radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Belli, M.; Tabocchini, M.A. [Istituto Superiore di Sanita, Rome (Italy). Physics Lab.; Sapora, O. [Istituto Superiore di Sanita, Rome (Italy). Comparative Toxicology Lab.

    2002-12-01

    DNA repair systems and cell cycle checkpoints closely co-operate in the attempt of maintaining the genomic integrity of cells damaged by ionizing radiation. DNA double-strand breaks (DSB) are considered as the most biologically important radiation-induced damage. Their spatial distribution and association with other types of damage depend on radiation quality. It is believed these features affect damage reparability, thus explaining the higher efficiency for cellular effects of densely ionizing radiation with respect to {gamma}-rays. DSB repair systems identified in mammalian cells are homologous recombination (HR), single-strand annealing (SSA) and non-homologous end-joining (NHEJ). Some enzymes may participate in more than one of these repair systems. DNA damage also triggers biochemical signals activating checkpoints responsible for delay in cell cycle progression that allows more time for repair. Those at G1/S and S phases prevent replication of damaged DNA and those at G2/M phase prevent segregation of changed chromosomes. Individuals with lack or alterations of genes involved in DNA DSB repair and cell cycle checkpoints exhibit syndromes characterized by genome instability and predisposition to cancer. Information reviewed in this paper on the basic mechanisms of cellular response to ionizing radiation indicates their importance for a number of issues relevant to protection of astronauts from space radiation. (author)

  14. Hormesis, cellular stress response and neuroinflammation in schizophrenia: Early onset versus late onset state.

    Science.gov (United States)

    Calabrese, Vittorio; Giordano, James; Crupi, Rosalia; Di Paola, Rosanna; Ruggieri, Martino; Bianchini, Rio; Ontario, Maria Laura; Cuzzocrea, Salvatore; Calabrese, Edward J

    2017-05-01

    Abnormal redox homeostasis and oxidative stress have been proposed to play a role in the etiology of several neuropsychiatric spectrum disorders. Emerging interest has recently focused on markers of oxidative stress and neuroinflammation in schizophrenic spectrum disorders, at least in particular subgroups of patients. Altered expression of genes related to oxidative stress, oxidative damage to DNA, protein and lipids, as well as reduced glutathione levels in central and peripheral tissues could act synergistically, and contribute to the course of the disease.  Herein, we discuss cellular mechanisms that may be operative in neuroinflammation and contributory to schizophrenia. We address modulation of endogenous cellular defense mechanisms as a potentially innovative approach to therapeutics for schizophrenia, and other neuropsychiatric conditions that are associated with neuroinflammation. Specifically, we discuss the emerging role of heme oxygenase as prominent member of neuroprotective network in redox stress responsive mechanisms, as well as the importance of glutathione relevant in schizophrenia pathophysiology. Finally we introduce the hormetic dose response concept as relevant and important to neuroprotection, and review hormetic mechanisms as possible approaches to manipulation of neuroinflammatory targets that may be viable for treating schizophrenia spectrum disorders. © 2016 Wiley Periodicals, Inc.

  15. More Than a Pore: The Cellular Response to Cholesterol-Dependent Cytolysins

    Directory of Open Access Journals (Sweden)

    Sara K. B. Cassidy

    2013-04-01

    Full Text Available Targeted disruption of the plasma membrane is a ubiquitous form of attack used in all three domains of life. Many bacteria secrete pore-forming proteins during infection with broad implications for pathogenesis. The cholesterol-dependent cytolysins (CDC are a family of pore-forming toxins expressed predominately by Gram-positive bacterial pathogens. The structure and assembly of some of these oligomeric toxins on the host membrane have been described, but how the targeted cell responds to intoxication by the CDCs is not as clearly understood. Many CDCs induce lysis of their target cell and can activate apoptotic cascades to promote cell death. However, the extent to which intoxication causes cell death is both CDC- and host cell-dependent, and at lower concentrations of toxin, survival of intoxicated host cells is well documented. Additionally, the effect of CDCs can be seen beyond the plasma membrane, and it is becoming increasingly clear that these toxins are potent regulators of signaling and immunity, beyond their role in intoxication. In this review, we discuss the cellular response to CDC intoxication with emphasis on the effects of pore formation on the host cell plasma membrane and subcellular organelles and whether subsequent cellular responses contribute to the survival of the affected cell.

  16. Biosorption and biodegradation of pyrene by Brevibacillus brevis and cellular responses to pyrene treatment.

    Science.gov (United States)

    Liao, Liping; Chen, Shuona; Peng, Hui; Yin, Hua; Ye, Jinshao; Liu, Zehua; Dang, Zhi; Liu, Zhichen

    2015-05-01

    Biodegradation has been proposed as an effective approach to remove pyrene, however, the information regarding cellular responses to pyrene treatment is limited thus far. In this study, the biodegradation and biosorption of pyrene by Brevibacillus brevis, along with cellular responses caused by pollutant were investigated by means of flow cytometry assay and scanning electron microscopy. The experimental results showed that pyrene was initially adsorbed by B. brevis and subsequently transported and intracellularly degraded. During this process, pyrene removal was primarily dependent on biodegradation. Cell invagination and cell surface corrugation occurred due to pyrene exposure. Nevertheless, cell regrowth after 96h treatment was observed, and the proportion of necrotic cell was only 2.8% after pyrene exposure for 120h, confirming that B. brevis could utilize pyrene as a sole carbon source for growth. The removal and biodegradation amount of pyrene (1mg/L) at 168h were 0.75 and 0.69mg/L, respectively, and the biosorption amount by inactivated cells was 0.41mg/L at this time.

  17. Trichothiodystrophy, a human DNA repair disorder with heterogeneity in the cellular response to ultraviolet light

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, A.R.; Arlett, C.F.; Broughton, B.C.; Harcourt, S.A.; Steingrimsdottir, H.; Stefanini, M.; Malcolm, A.; Taylor, R.; Natarajan, A.T.; Green, S.

    1988-11-01

    Trichothiodystrophy (TTD) is an autosomal recessive disorder characterized by brittle hair with reduced sulfur content, ichthyosis, peculiar face, and mental and physical retardation. Some patients are photosensitive. A previous study by Stefanini et al. showed that cells from four photosensitive patients with TTD had a molecular defect in DNA repair, which was not complemented by cells from xeroderma pigmentosum, complementation group D. In a detailed molecular and cellular study of the effects of UV light on cells cultured from three further TTD patients who did not exhibit photosensitivity we have found an array of different responses. In cells from the first patient, survival, excision repair, and DNA and RNA synthesis following UV irradiation were all normal, whereas in cells from the second patient all these responses were similar to those of excision-defective xeroderma pigmentosum (group D) cells. With the third patient, cell survival measured by colony-forming ability was normal following UV irradiation, even though repair synthesis was only 50% of normal and RNA synthesis was severely reduced. The excision-repair defect in these cells was not complemented by other TTD cell strains. These cellular characteristics of patient 3 have not been described previously for any other cell line. The normal survival may be attributed to the finding that the deficiency in excision-repair is confined to early times after irradiation. Our results pose a number of questions about the relationship between the molecular defect in DNA repair and the clinical symptoms of xeroderma pigmentosum and TTD.

  18. Impaired response of mature adipocytes of diabetic mice to hypoxia

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Seok Jong, E-mail: seok-hong@northwestern.edu; Jin, Da P.; Buck, Donald W.; Galiano, Robert D.; Mustoe, Thomas A., E-mail: tmustoe@nmh.org

    2011-10-01

    Adipose tissue contains various cells such as infiltrated monocytes/macrophages, endothelial cells, preadipocytes, and adipocytes. Adipocytes have an endocrine function by secreting adipokines such as interleukin (IL)-6, tumor necrosis factor (TNF)-{alpha}, leptin, and adiponectin. Dysregulation of adipokines in adipose tissues leads to a chronic low-grade inflammation which could result in atherosclerosis, hypertension, and type 2 diabetes. A sustained inflammatory state, which is characterized by prolonged persistence of macrophages and neutrophils, is found in diabetic wounds. In addition, subcutaneous adipocytes are enormously increased in amount clinically in type 2 diabetes. However, the function of subcutaneous adipocytes, which play an important role in injured tissue subjected to hypoxia, has not been well characterized in vitro due to the difficulty of maintaining mature adipocytes in culture using conventional methods because of their buoyancy. In this study, we established a novel in vitro culture method of mature adipocytes by enclosing them in a hyaluronan (HA) based hydrogel to study their role in response to stress such as hypoxia. BrdU labeling and Ki67 immunostaining experiments showed that hydrogel enclosed mature adipocytes proliferate in vitro. Both mRNA and protein expression analyses for hypoxia regulated genes, such as vascular endothelial growth factor (VEGF) and heme oxygenase 1 (HO1), showed that mature adipocytes of wild type mice respond to hypoxia. In contrast, mature adipocytes of diabetic db/db and TallyHo mice did not efficiently respond to hypoxia. Our studies suggest that mature adipocytes are functionally active cells, and their abnormal function to hypoxia can be one of underlining mechanisms in type 2 diabetes.

  19. Targeting Anabolic Impairment in Response to Resistance Exercise in Older Adults with Mobility Impairments: Potential Mechanisms and Rehabilitation Approaches

    Directory of Open Access Journals (Sweden)

    Micah J. Drummond

    2012-01-01

    Full Text Available Muscle atrophy is associated with healthy aging (i.e., sarcopenia and may be compounded by comorbidities, injury, surgery, illness, and physical inactivity. While a bout of resistance exercise increases protein synthesis rates in healthy young skeletal muscle, the effectiveness of resistance exercise to mount a protein synthetic response is less pronounced in older adults. Improving anabolic sensitivity to resistance exercise, thereby enhancing physical function, is most critical in needy older adults with clinical conditions that render them “low responders”. In this paper, we discuss potential mechanisms contributing to anabolic impairment to resistance exercise and highlight the need to improve anabolic responsiveness in low responders. This is followed with evidence suggesting that the recovery period of resistance exercise provides an opportunity to amplify the exercise-induced anabolic response using protein/essential amino acid ingestion. This anabolic strategy, if repeated chronically, may improve lean muscle gains, decrease time to recovery of function during periods of rehabilitation, and overall, maintain/improve physical independence and reduce mortality rates in older adults.

  20. Lengthening our perspective: morphological, cellular, and molecular responses to eccentric exercise.

    Science.gov (United States)

    Hyldahl, Robert D; Hubal, Monica J

    2014-02-01

    The response of skeletal muscle to unaccustomed eccentric exercise has been studied widely, yet it is incompletely understood. This review is intended to provide an up-to-date overview of our understanding of how skeletal muscle responds to eccentric actions, with particular emphasis on the underlying molecular and cellular mechanisms of damage and recovery. This review begins by addressing the question of whether eccentric actions result in physical damage to muscle fibers and/or connective tissue. We next review the symptomatic manifestations of eccentric exercise (i.e., indirect damage markers, such as delayed onset muscle soreness), with emphasis on their relatively poorly understood molecular underpinnings. We then highlight factors that potentially modify the muscle damage response following eccentric exercise. Finally, we explore the utility of using eccentric training to improve muscle function in populations of healthy and aging individuals, as well as those living with neuromuscular disorders. Copyright © 2013 Wiley Periodicals, Inc.

  1. 7th International Workshop on Microbeam Probes of Cellular Radiation Response

    Energy Technology Data Exchange (ETDEWEB)

    Brenner, David J.

    2009-07-21

    The extended abstracts that follow present a summary of the Proceedings of the 7th International Workshop: Microbeam Probes of Cellular Radiation Response, held at Columbia University’s Kellogg Center in New York City on March 15–17, 2006. These International Workshops on Microbeam Probes of Cellular Radiation Response have been held regularly since 1993 (1–5). Since the first workshop, there has been a rapid growth (see Fig. 1) in the number of centers developing microbeams for radiobiological research, and worldwide there are currently about 30 microbeams in operation or under development. Single-cell/single-particle microbeam systems can deliver beams of different ionizing radiations with a spatial resolution of a few micrometers down to a few tenths of a micrometer. Microbeams can be used to addressquestions relating to the effects of low doses of radiation (a single radiation track traversing a cell or group of cells), to probe subcellular targets (e.g. nucleus or cytoplasm), and to address questions regarding the propagation of information about DNA damage (for example, the radiation-induced bystander effect). Much of the recent research using microbeams has been to study low-dose effects and ‘‘non-targeted’’ responses such as bystander effects, genomic instability and adaptive responses. This Workshop provided a forum to assess the current state of microbeam technology and current biological applications and to discuss future directions for development, both technological and biological. Over 100 participants reviewed the current state of microbeam research worldwide and reported on new technological developments in the fields of both physics and biology.

  2. Maize Prolamins Could Induce a Gluten-Like Cellular Immune Response in Some Celiac Disease Patients

    Science.gov (United States)

    Ortiz-Sánchez, Juan P.; Cabrera-Chávez, Francisco; Calderón de la Barca, Ana M.

    2013-01-01

    Celiac disease (CD) is an autoimmune-mediated enteropathy triggered by dietary gluten in genetically prone individuals. The current treatment for CD is a strict lifelong gluten-free diet. However, in some CD patients following a strict gluten-free diet, the symptoms do not remit. These cases may be refractory CD or due to gluten contamination; however, the lack of response could be related to other dietary ingredients, such as maize, which is one of the most common alternatives to wheat used in the gluten-free diet. In some CD patients, as a rare event, peptides from maize prolamins could induce a celiac-like immune response by similar or alternative pathogenic mechanisms to those used by wheat gluten peptides. This is supported by several shared features between wheat and maize prolamins and by some experimental results. Given that gluten peptides induce an immune response of the intestinal mucosa both in vivo and in vitro, peptides from maize prolamins could also be tested to determine whether they also induce a cellular immune response. Hypothetically, maize prolamins could be harmful for a very limited subgroup of CD patients, especially those that are non-responsive, and if it is confirmed, they should follow, in addition to a gluten-free, a maize-free diet. PMID:24152750

  3. Actin polymerization negatively regulates p53 function by impairing its nuclear import in response to DNA damage.

    Directory of Open Access Journals (Sweden)

    Ling Wang

    Full Text Available Actin, one of the most evolutionarily conservative proteins in eukaryotes, is distributed both in the cytoplasm and the nucleus, and its dynamics plays important roles in numerous cellular processes. Previous evidence has shown that actin interacts with p53 and this interaction increases in the process of p53 responding to DNA damage, but the physiological significance of their interaction remains elusive. Here, we show that DNA damage induces both actin polymerization and p53 accumulation. To further understand the implication of actin polymerization in p53 function, cells were treated with actin aggregation agent. We find that the protein level of p53 decrease. The change in p53 is a consequence of the polymeric actin anchoring p53 in the cytoplasm, thus impairing p53 nuclear import. Analysis of phosphorylation and ubiquitination of p53 reveals that actin polymerization promotes the p53 phosphorylation at Ser315 and reduces the stabilization of p53 by recruiting Aurora kinase A. Taken together, our results suggest that the actin polymerization serves as a negative modulator leading to the impairment of nuclear import and destabilization of p53. On the basis of our results, we propose that actin polymerization might be a factor participating in the process of orchestrating p53 function in response to DNA damage.

  4. The NRF2 Activation and Antioxidative Response Are Not Impaired Overall during Hyperoxia-Induced Lung Epithelial Cell Death

    Directory of Open Access Journals (Sweden)

    Haranatha R. Potteti

    2013-01-01

    Full Text Available Lung epithelial and endothelial cell death caused by pro-oxidant insults is a cardinal feature of acute lung injury/acute respiratory distress syndrome (ALI/ARDS patients. The NF-E2-related factor 2 (NRF2 activation in response to oxidant exposure is crucial to the induction of several antioxidative and cytoprotective enzymes that mitigate cellular stress. Since prolonged exposure to hyperoxia causes cell death, we hypothesized that chronic hyperoxia impairs NRF2 activation, resulting in cell death. To test this hypothesis, we exposed nonmalignant small airway epithelial cells (AECs to acute (1–12 h and chronic (36–48 h hyperoxia and evaluated cell death, NRF2 nuclear accumulation and target gene expression, and NRF2 recruitment to the endogenous HMOX1 and NQO1 promoters. As expected, hyperoxia gradually induced death in AECs, noticeably and significantly by 36 h; ~60% of cells were dead by 48 h. However, we unexpectedly found increased expression levels of NRF2-regulated antioxidative genes and nuclear NRF2 in AECs exposed to chronic hyperoxia as compared to acute hyperoxia. Chromatin Immunoprecipitation (ChIP assays revealed an increased recruitment of NRF2 to the endogenous HMOX1 and NQO1 promoters in AECs exposed to acute or chronic hyperoxia. Thus, our findings demonstrate that NRF2 activation and antioxidant gene expression are functional during hyperoxia-induced lung epithelial cell death and that chronic hyperoxia does not impair NRF2 signaling overall.

  5. Engineering Cellular Microenvironments with Photo- and Enzymatically Responsive Hydrogels: Toward Biomimetic 3D Cell Culture Models.

    Science.gov (United States)

    Tam, Roger Y; Smith, Laura J; Shoichet, Molly S

    2017-04-18

    Conventional cell culture techniques using 2D polystyrene or glass have provided great insight into key biochemical mechanisms responsible for cellular events such as cell proliferation, differentiation, and cell-cell interactions. However, the physical and chemical properties of 2D culture in vitro are dramatically different than those found in the native cellular microenvironment in vivo. Cells grown on 2D substrates differ significantly from those grown in vivo, and this explains, in part, why many promising drug candidates discovered through in vitro drug screening assays fail when they are translated to in vivo animal or human models. To overcome this obstacle, 3D cell culture using biomimetic hydrogels has emerged as an alternative strategy to recapitulate native cell growth in vitro. Hydrogels, which are water-swollen polymers, can be synthetic or naturally derived. Many methods have been developed to control the physical and chemical properties of the hydrogels to match those found in specific tissues. Compared to 2D culture, cells cultured in 3D gels with the appropriate physicochemical cues can behave more like they naturally do in vivo. While conventional hydrogels involve modifications to the bulk material to mimic the static aspects of the cellular microenvironment, recent progress has focused on using more dynamic hydrogels, the chemical and physical properties of which can be altered with external stimuli to better mimic the dynamics of the native cellular microenvironment found in vivo. In this Account, we describe our progress in designing stimuli-responsive, optically transparent hydrogels that can be used as biomimetic extracellular matrices (ECMs) to study cell differentiation and migration in the context of modeling the nervous system and cancer. Specifically, we developed photosensitive agarose and hyaluronic acid hydrogels that are activated by single or two-photon irradiation for biomolecule immobilization at specific volumes within the 3D

  6. Atypical Brain Responses to Sounds in Children with Specific Language and Reading Impairments

    Science.gov (United States)

    McArthur, Genevieve; Atkinson, Carmen; Ellis, Danielle

    2009-01-01

    This study tested if children with specific language impairment (SLI) or children with specific reading disability (SRD) have abnormal brain responses to sounds. We tested 6- to 12-year-old children with SLI (N = 19), children with SRD (N = 55), and age-matched controls (N = 36) for their passive auditory event-related potentials (ERPs) to tones,…

  7. Effect of functional electrostimulation on impaired skin vasodilator responses to local heating in spinal cord injury.

    NARCIS (Netherlands)

    Duijnhoven, N.T.L. van; Janssen, T.W.; Green, D.J.; Minson, C.T.; Hopman, M.T.E.; Thijssen, D.H.J.

    2009-01-01

    Spinal cord injury (SCI) induces vascular adaptations below the level of the lesion, such as impaired cutaneous vasodilation. However, the mechanisms underlying these differences are unclear. The aim of this study is to examine arm and leg cutaneous vascular conductance (CVC) responses to local heat

  8. Sleep deprivation impairs contextual fear conditioning and attenuates subsequent behavioural, endocrine and neuronal responses

    NARCIS (Netherlands)

    Hagewoud, Roelina; Bultsma, Lillian J.; Barf, R. Paulien; Koolhaas, Jaap M.; Meerlo, Peter

    2011-01-01

    Sleep deprivation (SD) affects hippocampus-dependent memory formation. Several studies in rodents have shown that brief SD immediately following a mild foot shock impairs consolidation of contextual fear memory as reflected in a reduced behavioural freezing response during re-exposure to the shock c

  9. Total Physical Response: An Instructional Strategy for Second-Language Learners Who Are Visually Impaired.

    Science.gov (United States)

    Conroy, Paula

    1999-01-01

    Describes Total Physical Response, a teaching technique that teachers of English-as-a-Second-Language (ESL) use to instruct students who are in the process of learning a second language and modifications that can be made to the program to teach students with visual impairments. (CR)

  10. Impaired dynamic cerebrovascular response to hypercapnia predicts development of white matter hyperintensities

    Directory of Open Access Journals (Sweden)

    Kevin Sam

    2016-01-01

    Conclusions: Vascular impairment in regions of NAWM that progresses to WMH consists not only of decreased magnitude of ssCVR, but also a pathological decrease in the speed of vascular response. These findings support the association between cerebrovascular dysregulation and the development of WMH.

  11. Associations between Responsible Beverage Service Laws and Binge Drinking and Alcohol-Impaired Driving

    Science.gov (United States)

    Linde, Ann C.; Toomey, Traci L.; Wolfson, Julian; Lenk, Kathleen M.; Jones-Webb, Rhonda; Erickson, Darin J.

    2016-01-01

    We explored potential associations between the strength of state Responsible Beverage Service (RBS) laws and self-reported binge drinking and alcohol-impaired driving in the U.S. A multi-level logistic mixed-effects model was used, adjusting for potential confounders. Analyses were conducted on the overall BRFSS sample and drinkers only. Seven…

  12. Differential effects of IL-15 on the generation, maintenance and cytotoxic potential of adaptive cellular responses induced by DNA vaccination.

    Science.gov (United States)

    Li, Jinyao; Valentin, Antonio; Ng, Sinnie; Beach, Rachel Kelly; Alicea, Candido; Bergamaschi, Cristina; Felber, Barbara K; Pavlakis, George N

    2015-02-25

    IL-15 is an important cytokine for the regulation of lymphocyte homeostasis. However, the role of IL-15 in the generation, maintenance and cytotoxic potential of antigen specific T cells is not fully understood. Because the route of antigenic delivery and the vaccine modality could influence the IL-15 requirement for mounting and preserving cytotoxic T cell responses, we have investigated the immunogenicity of DNA-based vaccines in IL-15 KO mice. DNA vaccination with SIV Gag induced antigen-specific CD4(+) and CD8(+) T cells in the absence of IL-15. However, the absolute number of antigen-specific CD8(+) T cells was decreased in IL-15 KO mice compared to WT animals, suggesting that IL-15 is important for the generation of maximal number of antigen-specific CD8(+) T cells. Interestingly, antigen-specific memory CD8 cells could be efficiently boosted 8 months after the final vaccination in both WT and KO strains of mice, suggesting that the maintenance of antigen-specific long-term memory T cells induced by DNA vaccination is comparable in the absence and presence of IL-15. Importantly, boosting by DNA 8-months after vaccination revealed severely reduced granzyme B content in CD8(+) T cells of IL-15 KO mice compared to WT mice. This suggests that the cytotoxic potential of the long-term memory CD8(+) T cells is impaired. These results suggest that IL-15 is not essential for the generation and maintenance of adaptive cellular responses upon DNA vaccination, but it is critical for the preservation of maximal numbers and for the activity of cytotoxic CD8(+) T cells. Published by Elsevier Ltd.

  13. C/EBPγ Is a Critical Regulator of Cellular Stress Response Networks through Heterodimerization with ATF4

    Science.gov (United States)

    Huggins, Christopher J.; Mayekar, Manasi K.; Martin, Nancy; Saylor, Karen L.; Gonit, Mesfin; Jailwala, Parthav; Kasoji, Manjula; Haines, Diana C.; Quiñones, Octavio A.

    2015-01-01

    The integrated stress response (ISR) controls cellular adaptations to nutrient deprivation, redox imbalances, and endoplasmic reticulum (ER) stress. ISR genes are upregulated in stressed cells, primarily by the bZIP transcription factor ATF4 through its recruitment to cis-regulatory C/EBP:ATF response elements (CAREs) together with a dimeric partner of uncertain identity. Here, we show that C/EBPγ:ATF4 heterodimers, but not C/EBPβ:ATF4 dimers, are the predominant CARE-binding species in stressed cells. C/EBPγ and ATF4 associate with genomic CAREs in a mutually dependent manner and coregulate many ISR genes. In contrast, the C/EBP family members C/EBPβ and C/EBP homologous protein (CHOP) were largely dispensable for induction of stress genes. Cebpg−/− mouse embryonic fibroblasts (MEFs) proliferate poorly and exhibit oxidative stress due to reduced glutathione levels and impaired expression of several glutathione biosynthesis pathway genes. Cebpg−/− mice (C57BL/6 background) display reduced body size and microphthalmia, similar to ATF4-null animals. In addition, C/EBPγ-deficient newborns die from atelectasis and respiratory failure, which can be mitigated by in utero exposure to the antioxidant, N-acetyl-cysteine. Cebpg−/− mice on a mixed strain background showed improved viability but, upon aging, developed significantly fewer malignant solid tumors than WT animals. Our findings identify C/EBPγ as a novel antioxidant regulator and an obligatory ATF4 partner that controls redox homeostasis in normal and cancerous cells. PMID:26667036

  14. Short-term cigarette smoke exposure induces reversible changes in energy metabolism and cellular redox status independent of inflammatory responses in mouse lungs.

    Science.gov (United States)

    Agarwal, Amit R; Zhao, Liqin; Sancheti, Harsh; Sundar, Isaac K; Rahman, Irfan; Cadenas, Enrique

    2012-11-15

    Cigarette smoking leads to alteration in cellular redox status, a hallmark in the pathogenesis of chronic obstructive pulmonary disease. This study examines the role of cigarette smoke (CS) exposure in the impairment of energy metabolism and, consequently, mitochondrial dysfunction. Male A/J mice were exposed to CS generated by a smoking machine for 4 or 8 wk. A recovery group was exposed to CS for 8 wk and allowed to recover for 2 wk. Acute CS exposure altered lung glucose metabolism, entailing a decrease in the rate of glycolysis and an increase in the pentose phosphate pathway, as evidenced by altered expression and activity of GAPDH and glucose-6-phosphate dehydrogenase, respectively. Impairment of GAPDH was found to be due to glutathionylation of its catalytic site cysteines. Metabolic changes were associated with changes in cellular and mitochondrial redox status, assessed in terms of pyridine nucleotides and glutathione. CS exposure elicited an upregulation of the expression of complexes II, III, IV, and V and of the activity of complexes II, IV, and V. Microarray analysis of gene expression in mouse lungs after exposure to CS for 8 wk revealed upregulation of a group of genes involved in metabolism, electron transfer chain, oxidative phosphorylation, mitochondrial transport and dynamics, and redox regulation. These changes occurred independently of inflammatory responses. These findings have implications for the early onset of alterations in energy and redox metabolism upon acute lung exposure to CS.

  15. Cellular immune responses and occult infection in seronegative heterosexual partners of chronic hepatitis C patients.

    Science.gov (United States)

    Roque-Cuéllar, M C; Sánchez, B; García-Lozano, J R; Praena-Fernández, J M; Núñez-Roldán, A; Aguilar-Reina, J

    2011-10-01

    It is unknown whether hepatitis C virus (HCV)-specific cellular immune responses can develop in seronegative sexual partners of chronically HCV-infected patients and whether they have occult infection. Thirty-one heterosexual partners of patients with chronic HCV were studied, fifteen of them with HCV transmission risks. Ten healthy individuals and 17 anti-HCV seropositive patients, without viremia, were used as controls. Virus-specific CD4+ and CD8+ T-cell responses were measured by flow cytometry against six HCV peptides, situated within the nonstructural (NS) proteins NS3, NS4 and NS5, through intracellular detection of gamma interferon (IFN-γ) or interleukin 4 (IL-4) production and CD69 expression. Sexual partners had a higher production of IFN-γ and IL-4 by CD4+ cells against NS3-p124 (P = 0.003), NS5b-p257 (P = 0.005) and NS5b-p294 (P = 0.012), and CD8+ cells against NS3-p124 (P = 0.002), NS4b-p177 (P = 0.001) and NS3-p294 (P = 0.004) as compared with healthy controls. We observed elevated IFN-γ production by CD4+ T cells against NS5b-p257 (P = 0.042) and NS5b-p294 (P = 0.009) in the sexual partners with HCV transmission risks (sexual, professional and familial altogether) than in those without risks. RNA was extracted from peripheral blood mononuclear cells (PBMC), and detection of HCV-RNA positive and replicative (negative) strands was performed by strand-specific real-time PCR. In four sexual partners, the presence of positive and negative HCV- RNA strands in PBMC was confirmed. Hence, we found an HCV-specific cellular immune response as well as occult HCV infection in seronegative and aviremic sexual partners of chronically HCV-infected patients.

  16. Pneumococcal polysaccharide vaccine responses are impaired in a subgroup of children with cystic fibrosis.

    Science.gov (United States)

    Browning, Michael J; Lim, Michael T C; Kenia, Priti; Whittle, Michelle; Doffinger, Rainer; Barcenas-Morales, Gabriela; Kumararatne, Dinakantha; Viskaduraki, Maria; O'Callaghan, Christopher; Gaillard, Erol A

    2014-12-01

    Pneumococcal immunization is recommended in children with cystic fibrosis (CF). To date, however, there are no published studies on the efficacy of pneumococcal vaccination in this group of patients. We carried out a retrospective study of serotype-specific pneumococcal antibody responses to immunization with Prevenar 7 and Pneumovax II in a cohort of children with CF. Nine children had been immunized with Prevenar 7, and all had serotype-specific pneumococcal antibody levels in the protective range (>0.35mg/L) to all 7 immunizing serotypes. In contrast, only 7 of 33 patients (21%) immunized with Pneumovax II made protective antibody responses to all 7 serotypes, and 3 failed to make protective antibodies to any of the serotypes. Controlling for age as a confounder in the analysis, children with impaired antibody responses to pneumococcal polysaccharide (Pneumovax II) immunization had lower Shwachman-Kulczycki scores than children with normal polysaccharide antibody responses. All isolates of Pseudomonas aeruginosa occurred in patients with impaired anti-pneumococcal antibody responses, and a broader range of respiratory pathogens was isolated from these children. Impaired antibody responses to immunization with Pneumovax II are common in children with CF and this may be associated with increased disease severity. Copyright © 2014 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

  17. Cellular Immune Responses Associated with Occult Hepatitis C Virus Infection of the Liver

    Science.gov (United States)

    Quiroga, Juan A.; Llorente, Silvia; Castillo, Inmaculada; Rodríguez-Iñigo, Elena; Pardo, Margarita; Carreño, Vicente

    2006-01-01

    Occult hepatitis C virus (HCV) infection is a type of recently identified chronic infection that is evidenced only by detection of HCV RNA in liver; patients consistently test negative for antibodies to HCV and HCV RNA in serum. Using ex vivo and in vitro measures of T-cell responses, we have identified functional virus-specific memory CD4+ and CD8+ T cells in the peripheral blood of patients with occult HCV infection. The features of the virus-specific T cells were consistent with immune surveillance functions, supporting previous exposure to HCV. In addition, the magnitudes of CD4+ and CD8+ T-cell responses were in parallel and correlated inversely with the extent of liver HCV infection. The detection of HCV-specific T cells in individuals in whom HCV RNA can persist in the liver despite the absence of viremia and antibodies indicates that HCV replication is prolonged in the face of virus-specific CD4+ and CD8+ T-cell responses. These findings demonstrate that HCV-specific cellular immune responses are markers not only of previous exposure to and recovery from HCV but also of ongoing occult HCV infection. PMID:17071928

  18. Vaccination with dengue virus-like particles induces humoral and cellular immune responses in mice

    Directory of Open Access Journals (Sweden)

    Zhang Quanfu

    2011-06-01

    Full Text Available Abstract Background The incidence of dengue, an infectious disease caused by dengue virus (DENV, has dramatically increased around the world in recent decades and is becoming a severe public health threat. However, there is currently no specific treatment for dengue fever, and licensed vaccine against dengue is not available. Vaccination with virus-like particles (VLPs has shown considerable promise for many viral diseases, but the effect of DENV VLPs to induce specific immune responses has not been adequately investigated. Results By optimizing the expression plasmids, recombinant VLPs of four antigenically different DENV serotypes DENV1-4 were successfully produced in 293T cells. The vaccination effect of dengue VLPs in mice showed that monovalent VLPs of each serotype stimulated specific IgG responses and potent neutralizing antibodies against homotypic virus. Tetravalent VLPs efficiently enhanced specific IgG and neutralizing antibodies against all four serotypes of DENV. Moreover, vaccination with monovalent or tetravalent VLPs resulted in the induction of specific cytotoxic T cell responses. Conclusions Mammalian cell expressed dengue VLPs are capable to induce VLP-specific humoral and cellular immune responses in mice, and being a promising subunit vaccine candidate for prevention of dengue virus infection.

  19. In vivo cellular uptake of glutamate is impaired in the rat hippocampus during and after transient cerebral ischemia

    DEFF Research Database (Denmark)

    Bruhn, T; Christensen, Thomas; Diemer, Nils Henrik

    2001-01-01

    added to the dialysis perfusate, and the cellular extraction of (3)H-D-aspartate was calculated from scintillation analysis of fractionated dialysate samples. The extraction of (3)H-D-aspartate was studied both in a tracer like condition with a perfusate concentration of 0.2 microM, and in a condition...... of high saturation level, with 1.0 mM D-aspartate added to the perfusate. In between radioisotope perfusions, dialysate was sampled for analysis of amino acid content by HPLC. During ischemia, extraction of (3)H-D-aspartate (0.2 microM) declined to a maximum reduction of 68%. In the hours after ischemia...

  20. Lysophosphatidic acid receptor-5 negatively regulates cellular responses in mouse fibroblast 3T3 cells

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Yan; Hirane, Miku; Araki, Mutsumi [Division of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan); Fukushima, Nobuyuki [Division of Molecular Neurobiology, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan); Tsujiuchi, Toshifumi, E-mail: ttujiuch@life.kindai.ac.jp [Division of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan)

    2014-04-04

    Highlights: • LPA{sub 5} inhibits the cell growth and motile activities of 3T3 cells. • LPA{sub 5} suppresses the cell motile activities stimulated by hydrogen peroxide in 3T3 cells. • Enhancement of LPA{sub 5} on the cell motile activities inhibited by LPA{sub 1} in 3T3 cells. • The expression and activation of Mmp-9 were inhibited by LPA{sub 5} in 3T3 cells. • LPA signaling via LPA{sub 5} acts as a negative regulator of cellular responses in 3T3 cells. - Abstract: Lysophosphatidic acid (LPA) signaling via G protein-coupled LPA receptors (LPA{sub 1}–LPA{sub 6}) mediates a variety of biological functions, including cell migration. Recently, we have reported that LPA{sub 1} inhibited the cell motile activities of mouse fibroblast 3T3 cells. In the present study, to evaluate a role of LPA{sub 5} in cellular responses, Lpar5 knockdown (3T3-L5) cells were generated from 3T3 cells. In cell proliferation assays, LPA markedly stimulated the cell proliferation activities of 3T3-L5 cells, compared with control cells. In cell motility assays with Cell Culture Inserts, the cell motile activities of 3T3-L5 cells were significantly higher than those of control cells. The activity levels of matrix metalloproteinases (MMPs) were measured by gelatin zymography. 3T3-L5 cells stimulated the activation of Mmp-2, correlating with the expression levels of Mmp-2 gene. Moreover, to assess the co-effects of LPA{sub 1} and LPA{sub 5} on cell motile activities, Lpar5 knockdown (3T3a1-L5) cells were also established from Lpar1 over-expressing (3T3a1) cells. 3T3a1-L5 cells increased the cell motile activities of 3T3a1 cells, while the cell motile activities of 3T3a1 cells were significantly lower than those of control cells. These results suggest that LPA{sub 5} may act as a negative regulator of cellular responses in mouse fibroblast 3T3 cells, similar to the case for LPA{sub 1}.

  1. Regulation of Vascular Tone, Angiogenesis and Cellular Bioenergetics by the 3-Mercaptopyruvate Sulfurtransferase/H2S Pathway: Functional Impairment by Hyperglycemia and Restoration by DL-α-Lipoic Acid.

    Science.gov (United States)

    Coletta, Ciro; Módis, Katalin; Szczesny, Bartosz; Brunyánszki, Attila; Oláh, Gábor; Rios, Ester C S; Yanagi, Kazunori; Ahmad, Akbar; Papapetropoulos, Andreas; Szabo, Csaba

    2015-02-18

    Hydrogen sulfide (H2S), as a reducing agent and an antioxidant molecule, exerts protective effects against hyperglycemic stress in the vascular endothelium. The mitochondrial enzyme 3-mercaptopyruvate sulfurtransferase (3-MST) is an important biological source of H2S. We have recently demonstrated that 3-MST activity is inhibited by oxidative stress in vitro and speculated that this may have an adverse effect on cellular homeostasis. In the current study, given the importance of H2S as a vasorelaxant, angiogenesis stimulator and cellular bioenergetic mediator, we first determined whether the 3-MST/H2S system plays a physiological regulatory role in endothelial cells. Next, we tested whether a dysfunction of this pathway develops during the development of hyperglycemia and μmol/L to diabetes-associated vascular complications. Intraperitoneal (IP) 3-MP (1 mg/kg) raised plasma H2S levels in rats. 3-MP (10 1 mmol/L) promoted angiogenesis in vitro in bEnd3 microvascular endothelial cells and in vivo in a Matrigel assay in mice (0.3-1 mg/kg). In vitro studies with bEnd3 cell homogenates demonstrated that the 3-MP-induced increases in H2S production depended on enzymatic activity, although at higher concentrations (1-3 mmol/L) there was also evidence for an additional nonenzymatic H2S production by 3-MP. In vivo, 3-MP facilitated wound healing in rats, induced the relaxation of dermal microvessels and increased mitochondrial bioenergetic function. In vitro hyperglycemia or in vivo streptozotocin diabetes impaired angiogenesis, attenuated mitochondrial function and delayed wound healing; all of these responses were associated with an impairment of the proangiogenic and bioenergetic effects of 3-MP. The antioxidants DL-α-lipoic acid (LA) in vivo, or dihydrolipoic acid (DHLA) in vitro restored the ability of 3-MP to stimulate angiogenesis, cellular bioenergetics and wound healing in hyperglycemia and diabetes. We conclude that diabetes leads to an impairment of the 3-MST

  2. Comparison of cellular responses induced by low level light in different cell types

    Science.gov (United States)

    Huang, Ying-Ying; Chen, Aaron C.-H.; Sharma, Sulbha K.; Wu, Qiuhe; Hamblin, Michael R.

    2010-02-01

    Discoveries are rapidly being made in multiple laboratories that shed "light" on the fundamental molecular and cellular mechanisms underlying the use of low level light therapy (LLLT) in vitro, in animal models and in clinical practice. Increases in cellular levels of respiration, in cytochrome c oxidase activity, in ATP levels and in cyclic AMP have been found. Increased expression of reactive oxygen species and release of nitric oxide have also been shown. In order for these molecular changes to have a major effect on cell behavior, it is likely that various transcription factors will be activated, possibly via different signal transduction pathways. In this report we compare and contrast the effects of LLLT in vitro on murine embryonic fibroblasts, primary cortical neurons, cardiomyocytes and bone-marrow derived dendritic cells. We also examined two human cell lines, HeLa cancer cells and HaCaT keratinocytes. The effects of 810-nm near-infra-red light delivered at low and high fluences were addressed. Reactive oxygen species generation, transcription factor activation and ATP increases are reported. The data has led to the hypothesis that cells with a high level of mitochondrial activity (mitochondrial membrane potential) have a higher response to light than cells with low mitochondrial activity.

  3. Metabolic Discrimination of Select List Agents by Monitoring Cellular Responses in a Multianalyte Microphysiometer

    Directory of Open Access Journals (Sweden)

    John Wikswo

    2009-03-01

    Full Text Available Harnessing the potential of cells as complex biosensors promises the potential to create sensitive and selective detectors for discrimination of biodefense agents. Here we present toxin detection and suggest discrimination using cells in a multianalyte microphysiometer (MMP that is capable of simultaneously measuring flux changes in four extracellular analytes (acidification rate, glucose uptake, oxygen uptake, and lactate production in real-time. Differential short-term cellular responses were observed between botulinum neurotoxin A and ricin toxin with neuroblastoma cells, alamethicin and anthrax protective antigen with RAW macrophages, and cholera toxin, muscarine, 2,4-dinitro-phenol, and NaF with CHO cells. These results and the post exposure dynamics and metabolic recovery observed in each case suggest the usefulness of cell-based detectors to discriminate between specific analytes and classes of compounds in a complex matrix, and furthermore to make metabolic inferences on the cellular effects of the agents. This may be particularly valuable for classifying unknown toxins.

  4. Modified arteriolar responses to ATP after impairment of endothelium by light-dye techniques in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Koller, A.; Rodenburg, J.M.; Wolin, M.S.; Messina, E.J.; Kaley, G. (Department of Physiology, New York Medical College, Valhalla (USA))

    1991-01-01

    In this study we investigated whether endothelial cells are involved in the dilation of third-order arterioles (14 to 22 microns) in response to adenosine triphosphate (ATP) in cremaster muscle of pentobarbital-anesthetized rats. Two light/dye (L/D) techniques were employed to achieve selective, local endothelial impairment. One of these techniques utilizes a mercury lamp and sodium fluorescein, the other a Helium-Neon laser and Evans blue dye. L/D treatment (illumination with the appropriate wavelengths of light in the presence of an intravascular dye) of a 20-to 100-microns segment of an arteriole resulted in a complete loss of arteriolar dilation in response to topical administration of acetylcholine (10(-6) M) and arachidonic acid (AA, 10(-5) M). These agents were applied in 100-microl aliquots without interrupting the continuous suffusion with Ringer-gelatin solution and caused a {approximately} 70% increase in vascular diameter before the L/D intervention. Selectivity of the impairment was assessed by arteriolar responses to the nonendothelium-dependent dilator agents adenosine (10(-5) M) and sodium nitroprusside (2 {times} 10(-7) M), which elicited the same degree of dilation before and after L/D treatment. Under control conditions ATP (10(-6), 10(-5), and 10(-4) M) elicited dose-dependent increases in arteriolar diameter (from 38 to 74%). After impairment of arteriolar endothelium, dilation in response to all doses of ATP was significantly reduced. Theophylline (30 microM) significantly inhibited arteriolar dilation in response to adenosine (10(-6), 10(-5), and 10(-4) M) but did not affect the responses to various doses of ATP. Moreover, impairment of endothelium enhanced constrictor responses of arterioles to norepinephrine (0.6 {times} 10(-8) M).

  5. Cellular mechanisms for response heterogeneity among L2/3 pyramidal cells in whisker somatosensory cortex.

    Science.gov (United States)

    Elstrott, Justin; Clancy, Kelly B; Jafri, Haani; Akimenko, Igor; Feldman, Daniel E

    2014-07-15

    Whisker deflection evokes sparse, low-probability spiking among L2/3 pyramidal cells in rodent somatosensory cortex (S1), with spiking distributed nonuniformly between more and less responsive cells. The cellular and local circuit factors that determine whisker responsiveness across neurons are unclear. To identify these factors, we used two-photon calcium imaging and loose-seal recording to identify more and less responsive L2/3 neurons in S1 slices in vitro, during feedforward recruitment of the L2/3 network by L4 stimulation. We observed a broad gradient of spike recruitment thresholds within local L2/3 populations, with low- and high-threshold cells intermixed. This recruitment gradient was significantly correlated across different L4 stimulation sites, and between L4-evoked and whisker-evoked responses in vivo, indicating that a substantial component of responsiveness is independent of tuning to specific feedforward inputs. Low- and high-threshold L2/3 pyramidal cells differed in L4-evoked excitatory synaptic conductance and intrinsic excitability, including spike threshold and the likelihood of doublet spike bursts. A gradient of intrinsic excitability was observed across neurons. Cells that spiked most readily to L4 stimulation received the most synaptic excitation but had the lowest intrinsic excitability. Low- and high-threshold cells did not differ in dendritic morphology, passive membrane properties, or L4-evoked inhibitory conductance. Thus multiple gradients of physiological properties exist across L2/3 pyramidal cells, with excitatory synaptic input strength best predicting overall spiking responsiveness during network recruitment. Copyright © 2014 the American Physiological Society.

  6. Dopaminergic medication impairs feedback-based stimulus-response learning but not response selection in Parkinson’s disease

    Directory of Open Access Journals (Sweden)

    Andrew eVo

    2014-10-01

    Full Text Available Cognitive dysfunction is a feature of Parkinson’s Disease (PD. Some cognitive functions are impaired by dopaminergic medications prescribed to address the movement symptoms that typify PD. Learning appears to be the cognitive function most frequently worsened by dopaminergic therapy. However, this result could reflect either impairments in learning (i.e., acquisition of associations among stimuli, responses, and outcomes or deficits in performance based on learning (e.g., selecting responses. We sought to clarify the specific effects of dopaminergic medication on i stimulus-response association learning from outcome feedback and ii response selection based on learning in PD. We tested 28 PD patients on and/or off dopaminergic medication along with 32 healthy, age- and education-matched controls. In Session 1, participants learned to associate abstract images with specific key-press responses through trial and error via outcome feedback. In Session 2, participants provided specific responses to abstract images learned in Session 1, without feedback, precluding new feedback-based learning. By separating Sessions 1 and 2 by 24 hours, we could distinguish the effect of dopaminergic medication on a feedback-based learning and response selection processes in Session 1 versus on b response selection processes without feedback-based learning in Session 2, when performance accuracy across sessions was comparable. PD patients on medication learned stimulus-response associations more poorly than PD patients off medication and controls. Medication did not influence decision performance in Session 2 in the absence of feedback-based learning. We confirm that dopaminergic therapy impairs feedback-based learning in PD, discounting an alternative explanation that warranted consideration.

  7. Thioredoxin-dependent Redox Regulation of Cellular Signaling and Stress Response through Reversible Oxidation of Methionines

    Energy Technology Data Exchange (ETDEWEB)

    Bigelow, Diana J.; Squier, Thomas C.

    2011-06-01

    Generation of reactive oxygen species (ROS) is a common feature of many forms of stress to which plants are exposed. Successful adaptation to changing environmental conditions requires sensitive sensors of ROS such as protein-bound methionines that are converted to their corresponding methionine sulfoxides, which in turn can influence cellular signaling pathways. Such a signaling protein is calmodulin, which represents an early and central point in calcium signaling pathways important to stress response in plants. We describe recent work elucidating fundamental mechanisms of reversible methionine oxidation within calmodulin, including the sensitivity of individual methionines within plant and animal calmodulin to ROS, the structural and functional consequences of their oxidation, and the interactions of oxidized calmodulin with methionine sulfoxide reductase enzymes.

  8. Cellular Responses of Resistant and Susceptible Soybean Genotypes Infected with Meloidogyne arenaria Races 1 and 2.

    Science.gov (United States)

    Pedrosa, E M; Hussey, R S; Boerma, H R

    1996-06-01

    The cellular responses induced by Meloidogyne arenaria races 1 and 2 in three soybean genotypes, susceptible CNS, resistant Jackson, and resistant PI 200538, were examined by light microscopy 20 days after inoculation. Differences in giant-cell development were greater between races than among the soybean genotypes. M. arenaria race 1 stimulated small, poorly formed giant-cells in contrast with M. arenaria race 2, which induced well-developed, thick-walled, multinucleate giant-cells. The number of nuclei per giant-celt was variable, but fewer nuclei were usually present in giant-cells induced by race 1 (mean 16 nuclei) than in giant-cells induced by race 2 (mean 41 nuclei). Differences observed in giant-cell development were related to differences in growth and maturation of M. arenaria races 1 and 2 and host suitability of the soybean genotypes.

  9. Cellular Responses Evoked by Different Surface Characteristics of Intraosseous Titanium Implants

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    Liviu Feller

    2015-01-01

    Full Text Available The properties of biomaterials, including their surface microstructural topography and their surface chemistry or surface energy/wettability, affect cellular responses such as cell adhesion, proliferation, and migration. The nanotopography of moderately rough implant surfaces enhances the production of biological mediators in the peri-implant microenvironment with consequent recruitment of differentiating osteogenic cells to the implant surface and stimulates osteogenic maturation. Implant surfaces with moderately rough topography and with high surface energy promote osteogenesis, increase the ratio of bone-to-implant contact, and increase the bonding strength of the bone to the implant at the interface. Certain features of implant surface chemistry are also important in enhancing peri-implant bone wound healing. It is the purpose of this paper to review some of the more important features of titanium implant surfaces which have an impact on osseointegration.

  10. Impaired Cytokine Responses to Epstein-Barr Virus Antigens in Systemic Lupus Erythematosus Patients

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    Anette Holck Draborg

    2016-01-01

    Full Text Available We analyzed cytokine responses against latent and lytic Epstein-Barr virus (EBV antigens in systemic lupus erythematosus (SLE patients and healthy controls (HCs to obtain an overview of the distinctive immune regulatory response in SLE patients and to expand the previously determined impaired EBV-directed T-cell response. The concentrations of 14 cytokines (IL2, IL4, IL5, IL6, IL10, IL12, IL17, IL18, IL1β, IFNγ, TNFα, TNFβ, TGFβ, and GM-CSF were quantified upon stimulation of whole blood with latent state antigen EBNA1, lytic cycle antigen EBV-EA/D, and the superantigen SEB. To avoid results affected by lack of lymphocytes, we focused on SLE patients with normal levels. Decreased induction of IL12, IFNγ, IL17, and IL6 upon EBNA1 stimulation and that of IFNγ, IL6, TNFβ, IL1β, and GM-CSF upon EBV-EA/D stimulation were detected in SLE patients compared to HCs. IFNγ responses, especially, were shown to be reduced. Induction of several cytokines was furthermore impaired in SLE patients upon SEB stimulation, but no difference was observed in basic levels. Results substantiate the previously proposed impaired regulation of the immune response against latent and lytic cycle EBV infection in SLE patients without lymphopenia. Furthermore, results indicate general dysfunction of leukocytes and their cytokine regulations in SLE patients.

  11. Human papillomavirus (HPV upregulates the cellular deubiquitinase UCHL1 to suppress the keratinocyte's innate immune response.

    Directory of Open Access Journals (Sweden)

    Rezaul Karim

    Full Text Available Persistent infection of basal keratinocytes with high-risk human papillomavirus (hrHPV may cause cancer. Keratinocytes are equipped with different pattern recognition receptors (PRRs but hrHPV has developed ways to dampen their signals resulting in minimal inflammation and evasion of host immunity for sustained periods of time. To understand the mechanisms underlying hrHPV's capacity to evade immunity, we studied PRR signaling in non, newly, and persistently hrHPV-infected keratinocytes. We found that active infection with hrHPV hampered the relay of signals downstream of the PRRs to the nucleus, thereby affecting the production of type-I interferon and pro-inflammatory cytokines and chemokines. This suppression was shown to depend on hrHPV-induced expression of the cellular protein ubiquitin carboxyl-terminal hydrolase L1 (UCHL1 in keratinocytes. UCHL1 accomplished this by inhibiting tumor necrosis factor receptor-associated factor 3 (TRAF3 K63 poly-ubiquitination which lead to lower levels of TRAF3 bound to TANK-binding kinase 1 and a reduced phosphorylation of interferon regulatory factor 3. Furthermore, UCHL1 mediated the degradation of the NF-kappa-B essential modulator with as result the suppression of p65 phosphorylation and canonical NF-κB signaling. We conclude that hrHPV exploits the cellular protein UCHL1 to evade host innate immunity by suppressing PRR-induced keratinocyte-mediated production of interferons, cytokines and chemokines, which normally results in the attraction and activation of an adaptive immune response. This identifies UCHL1 as a negative regulator of PRR-induced immune responses and consequently its virus-increased expression as a strategy for hrHPV to persist.

  12. Transcriptional and cellular responses of the green alga Chlamydomonas reinhardtii to perfluoroalkyl phosphonic acids.

    Science.gov (United States)

    Sanchez, David; Houde, Magali; Douville, Mélanie; De Silva, Amila O; Spencer, Christine; Verreault, Jonathan

    2015-03-01

    Perfluoroalkyl phosphonic acids (PFPAs), a new class of perfluoroalkyl substances used primarily in the industrial sector as surfactants, were recently detected in surface water and wastewater treatment plant effluents. Toxicological effects of PFPAs have as yet not been investigated in aquatic organisms. The objective of the present study was to evaluate the effects of perfluorooctylphosphonic acid (C8-PFPA) and perfluorodecylphosphonic acid (C10-PFPA) exposure (31-250μg/L) on Chlamydomonas reinhardtii using genomic (qRT-PCR), biochemical (reactive oxygen species production (ROS) and lipid peroxidation), and physiological (cellular viability) indicators. After 72h of exposure, no differences were observed in cellular viability for any of the two perfluorochemicals. However, increase in ROS concentrations (36% and 25.6% at 125 and 250μg/L, respectively) and lipid peroxidation (35.5% and 35.7% at 125 and 250μg/L, respectively) was observed following exposure to C10-PFPA. C8-PFPA exposure did not impact ROS production and lipid peroxidation in algae. To get insights into the molecular response and modes of action of PFPA toxicity, qRT-PCR-based assays were performed to analyze the transcription of genes related to antioxidant responses including superoxide dismutase (SOD-1), glutathione peroxidase (GPX), catalase (CAT), glutathione S-transferase (GST), and ascorbate peroxidase (APX I). Genomic analyses revealed that the transcription of CAT and APX I was up-regulated for all the C10-PFPA concentrations. In addition, PFPAs were quantified in St. Lawrence River surface water samples and detected at concentrations ranging from 250 to 850pg/L for C8-PFPA and 380 to 650pg/L for C10-PFPA. This study supports the prevalence of PFPAs in the aquatic environment and suggests potential impacts of PFPA exposure on the antioxidant defensive system in C. reinhardtii. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

  13. Monitoring cellular stress responses to nanoparticles using a lab-on-a-chip.

    Science.gov (United States)

    Richter, Lukas; Charwat, Verena; Jungreuthmayer, Christian; Bellutti, Florian; Brueckl, Hubert; Ertl, Peter

    2011-08-07

    As nanotechnology moves towards widespread commercialization, new technologies are needed to adequately address the potential health impact of nanoparticles (NPs). Assessing the safety of over 30,000 NPs through animal testing would not only be expensive, but it would also raise a number of ethical considerations. Furthermore, existing in vitro cell-based assays are not sufficient in scope to adequately address the complexity of cell-nanoparticle interactions including NP translocation, accumulation and co-transport of e.g. allergens. In particular, classical optical/fluorescent endpoint detection methods are known to provide irreproducible, inaccurate and unreliable results since these labels can directly react with the highly catalytic surfaces of NP. To bridge this technological gap we have developed a lab-on-a-chip capable of continuously and non-invasively monitoring the collagen production of primary human fibroblast cells (NHDF) using contactless dielectric microsensors. Human dermal fibroblast cells are responsible for the maintenance of soft tissue integrity, are found throughout the human body and their primary function is collagen expression. We show that cellular collagen production can be readily detected and used to assess cellular stress responses to a variety of external stimuli, including exposure to nanoparticles. Results of the study showed a 20% and 95% reduction of collagen production following 4 hour exposure to 10 μg mL(-1) gold and silver nanoparticles (dia.10 nm), respectively. Furthermore a prolonged perfusion of sub-toxic concentrations (0.1 μg mL(-1)) of silver NP reduced NHDF collagen production by 40% after 10 h indicating increased NP take up and accumulation. We demonstrate that the application of microfluidics for the tailored administration of different NP treatments constitutes a powerful new tool to study cell-nanoparticle interactions and nanoparticle accumulation effects in small cell populations.

  14. Potential for cellular stress response to hepatic factor VIII expression from AAV vector

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    Irene Zolotukhin

    2016-01-01

    Full Text Available Hemophilia A and B are coagulation disorders resulting from the loss of functional coagulation factor VIII (FVIII or factor IX proteins, respectively. Gene therapy for hemophilia with adeno-associated virus vectors has shown efficacy in hemophilia B patients. Although hemophilia A patients are more prevalent, the development of therapeutic adeno-associated virus vectors has been impeded by the size of the F8 cDNA and impaired secretion of FVIII protein. Further, it has been reported that over-expression of the FVIII protein induces endoplasmic reticulum stress and activates the unfolded protein response pathway both in vitro and in hepatocytes in vivo, presumably due to retention of misfolded FVIII protein within the endoplasmic reticulum. Engineering of the F8 transgene, including removal of the B domain (BDD-FVIII and codon optimization, now allows for the generation of adeno-associated virus vectors capable of expressing therapeutic levels of FVIII. Here we sought to determine if the risks of inducing the unfolded protein response in murine hepatocytes extend to adeno-associated virus gene transfer. Although our data show a mild activation of unfolded protein response markers following F8 gene delivery at a certain vector dose in C57BL/6 mice, it was not augmented upon further elevated dosing, did not induce liver pathology or apoptosis, and did not impact FVIII immunogenicity.

  15. Potential for cellular stress response to hepatic factor VIII expression from AAV vector

    Science.gov (United States)

    Zolotukhin, Irene; Markusic, David M; Palaschak, Brett; Hoffman, Brad E; Srikanthan, Meera A; Herzog, Roland W

    2016-01-01

    Hemophilia A and B are coagulation disorders resulting from the loss of functional coagulation factor VIII (FVIII) or factor IX proteins, respectively. Gene therapy for hemophilia with adeno-associated virus vectors has shown efficacy in hemophilia B patients. Although hemophilia A patients are more prevalent, the development of therapeutic adeno-associated virus vectors has been impeded by the size of the F8 cDNA and impaired secretion of FVIII protein. Further, it has been reported that over-expression of the FVIII protein induces endoplasmic reticulum stress and activates the unfolded protein response pathway both in vitro and in hepatocytes in vivo, presumably due to retention of misfolded FVIII protein within the endoplasmic reticulum. Engineering of the F8 transgene, including removal of the B domain (BDD-FVIII) and codon optimization, now allows for the generation of adeno-associated virus vectors capable of expressing therapeutic levels of FVIII. Here we sought to determine if the risks of inducing the unfolded protein response in murine hepatocytes extend to adeno-associated virus gene transfer. Although our data show a mild activation of unfolded protein response markers following F8 gene delivery at a certain vector dose in C57BL/6 mice, it was not augmented upon further elevated dosing, did not induce liver pathology or apoptosis, and did not impact FVIII immunogenicity. PMID:27738644

  16. Involvement of Noxa in mediating cellular ER stress responses to lytic virus infection.

    Science.gov (United States)

    Rosebeck, Shaun; Sudini, Kuladeep; Chen, Tiannan; Leaman, Douglas W

    2011-09-01

    Noxa is a Bcl-2 homology domain-containing pro-apoptotic mitochondrial protein. Noxa mRNA and protein expression are upregulated by dsRNA or virus, and ectopic Noxa expression enhances cellular sensitivity to virus or dsRNA-induced apoptosis. Here we demonstrate that Noxa null baby mouse kidney (BMK) cells are deficient in normal cytopathic response to lytic viruses, and that reconstitution of the knockout cells with wild-type Noxa restored normal cytopathic responses. Noxa regulation by virus mirrored its regulation by proteasome inhibitors or ER stress inducers and the ER stress response inhibitor salubrinal protected cells against viral cytopathic effects. Noxa mRNA and protein were synergistically upregulated by IFN or dsRNA when combined with ER stress inducers, leading to Noxa/Mcl-1 interaction, activation of Bax and pro-apoptotic caspases, degradation of Mcl-1, loss of mitochondrial membrane potential and initiation of apoptosis. These data highlight the importance of ER stress in augmenting the expression of Noxa following viral infection.

  17. Time-lapse analysis of potential cellular responsiveness to Johrei, a Japanese healing technique

    Directory of Open Access Journals (Sweden)

    Moore Dan

    2005-01-01

    Full Text Available Abstract Background Johrei is an alternative healing practice which involves the channeling of a purported universal healing energy to influence the health of another person. Despite little evidence to support the efficacy of such practices the use of such treatments is on the rise. Methods We assessed cultured human cancer cells for potential responsiveness to Johrei treatment from a short distance. Johrei treatment was delivered by practitioners who participated in teams of two, alternating every half hour for a total of four hours of treatment. The practitioners followed a defined set of mental procedures to minimize variability in mental states between experiments. An environmental chamber maintained optimal growth conditions for cells throughout the experiments. Computerized time-lapse microscopy allowed documentation of cancer cell proliferation and cell death before, during and after Johrei treatments. Results Comparing eight control experiments with eight Johrei intervention experiments, we found no evidence of a reproducible cellular response to Johrei treatment. Conclusion Cell death and proliferation rates of cultured human cancer cells do not appear responsive to Johrei treatment from a short distance.

  18. Cellular, physiological, and molecular adaptive responses of Erwinia amylovora to starvation.

    Science.gov (United States)

    Santander, Ricardo D; Oliver, James D; Biosca, Elena G

    2014-05-01

    Erwinia amylovora causes fire blight, a destructive disease of rosaceous plants distributed worldwide. This bacterium is a nonobligate pathogen able to survive outside the host under starvation conditions, allowing its spread by various means such as rainwater. We studied E. amylovora responses to starvation using water microcosms to mimic natural oligotrophy. Initially, survivability under optimal (28 °C) and suboptimal (20 °C) growth temperatures was compared. Starvation induced a loss of culturability much more pronounced at 28 °C than at 20 °C. Natural water microcosms at 20 °C were then used to characterize cellular, physiological, and molecular starvation responses of E. amylovora. Challenged cells developed starvation-survival and viable but nonculturable responses, reduced their size, acquired rounded shapes and developed surface vesicles. Starved cells lost motility in a few days, but a fraction retained flagella. The expression of genes related to starvation, oxidative stress, motility, pathogenicity, and virulence was detected during the entire experimental period with different regulation patterns observed during the first 24 h. Further, starved cells remained as virulent as nonstressed cells. Overall, these results provide new knowledge on the biology of E. amylovora under conditions prevailing in nature, which could contribute to a better understanding of the life cycle of this pathogen.

  19. Development of cross-protective influenza A vaccines based on cellular responses

    Directory of Open Access Journals (Sweden)

    Peter Christiaan Soema

    2015-05-01

    Full Text Available Seasonal influenza vaccines provide protection against matching influenza A virus (IAV strains mainly through the induction of neutralizing serum IgG antibodies. However, these antibodies fail to confer a protective effect against mismatched IAV. This lack of efficacy against heterologous influenza strains has spurred the vaccine development community to look for other influenza vaccine concepts, which have the ability to elicit cross-protective immune responses.One of the concepts that is currently been worked on are influenza vaccines inducing influenza-specific T cell responses. T cells are able to lyse infected host cells, thereby clearing the virus. More interestingly, these T cells can recognize highly conserved epitopes of internal influenza proteins, making cellular responses less vulnerable to antigenic variability. T cells are therefore cross-reactive against many influenza strains, and thus are a promising concept for future influenza vaccines. Despite their potential, there are currently no T cell based IAV vaccines on the market. Selection of the proper antigen, appropriate vaccine formulation and evaluation of the efficacy of T cell vaccines remains challenging, both in preclinical and clinical settings.In this review, we will discuss the current developments in influenza T cell vaccines, focusing on existing protein-based and novel peptide-based vaccine formulations. Furthermore, we will discuss the feasibility of influenza T cell vaccines and their possible use in the future.

  20. Cellular and molecular responses of E. fetida coelomocytes exposed to TiO{sub 2} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Bigorgne, Emilie, E-mail: emilie.bigorgne@univ-lorraine.fr; Foucaud, Laurent [Universite de Lorraine-Laboratoire des Interactions Ecotoxicologique Biodiversite Ecosystemes (LIEBE) (France); Caillet, Celine [Universite de Lorraine-Laboratoire Environnement et Mineralurgie (LEM) CNRS UMR7569 (France); Giamberini, Laure; Nahmani, Johanne [Universite de Lorraine-Laboratoire des Interactions Ecotoxicologique Biodiversite Ecosystemes (LIEBE) (France); Thomas, Fabien [Universite de Lorraine-Laboratoire Environnement et Mineralurgie (LEM) CNRS UMR7569 (France); Rodius, Francois [Universite de Lorraine-Laboratoire des Interactions Ecotoxicologique Biodiversite Ecosystemes (LIEBE) (France)

    2012-07-15

    An in vitro approach using coelomocytes of Eisenia fetida was investigated to evaluate toxicity of TiO{sub 2} nanoparticles. Coelomocytes were exposed to well-dispersed suspension of small aggregates (130 nm) of TiO{sub 2} nanoparticles (1-25 {mu}g/ml) during 4, 12 and 24 h. Intracellular localisation suggested that the main route of uptake was endocytosis. Cellular responses showed that TiO{sub 2} nanoparticles were not cytotoxic and had no effect on phagocytosis at any of the four concentrations for each time tested. Concerning molecular responses, an increase of fetidin and metallothionein mRNA expression was observed starting from 4 h of exposure. In contrast, expression of coelomic cytolytic factor mRNA decreased for 10 and 25 {mu}g/ml after 4 h. Superoxide dismutase, catalase and glutathione-S-transferase expression were not modified suggesting that oxidative stress was not induced by TiO{sub 2} in our experimental conditions. This in vitro approach showed that TiO{sub 2} nanoparticles were taken up by coelomocytes and they could modify the molecular response of immune and detoxification system.

  1. Modelling cross-reactivity and memory in the cellular adaptive immune response to influenza infection in the host.

    Science.gov (United States)

    Yan, Ada W C; Cao, Pengxing; Heffernan, Jane M; McVernon, Jodie; Quinn, Kylie M; La Gruta, Nicole L; Laurie, Karen L; McCaw, James M

    2017-01-21

    The cellular adaptive immune response plays a key role in resolving influenza infection. Experiments where individuals are successively infected with different strains within a short timeframe provide insight into the underlying viral dynamics and the role of a cross-reactive immune response in resolving an acute infection. We construct a mathematical model of within-host influenza viral dynamics including three possible factors which determine the strength of the cross-reactive cellular adaptive immune response: the initial naive T cell number, the avidity of the interaction between T cells and the epitopes presented by infected cells, and the epitope abundance per infected cell. Our model explains the experimentally observed shortening of a second infection when cross-reactivity is present, and shows that memory in the cellular adaptive immune response is necessary to protect against a second infection. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Impaired cardiovascular responsiveness to an acute cold wind stress in streptozotocin-diabetic rats.

    Science.gov (United States)

    Kilgour, R D; Williams, P A

    1994-03-01

    In vivo cardiovascular responses were measured using modified impedance cardiographic techniques in urethane-anesthetized (1.5 g/kg) streptozotocin-diabetic (STZ; 65 mg/kg) rats during acute (30 min) cold wind (0 degree C, 1 m/s) exposure. Both control (CON) and diabetic (STZ) groups experienced significant decreases (P wind stress as evidenced by the impaired responsiveness of the cardiovascular system to hypothermia. The pattern of responses for both the thermoregulatory and cardiovascular systems could be partially explained by beta-receptor insensitivity to catecholamine stimulation.

  3. Staphylococcus aureus Strain Newman Photoinactivation and Cellular Response to Sunlight Exposure.

    Science.gov (United States)

    McClary, Jill S; Sassoubre, Lauren M; Boehm, Alexandria B

    2017-09-01

    Sunlight influences microbial water quality of surface waters. Previous studies have investigated photoinactivation mechanisms and cellular photostress responses of fecal indicator bacteria (FIB), including Escherichia coli and enterococci, but further work is needed to characterize photostress responses of bacterial pathogens. Here we investigate the photoinactivation of Staphylococcus aureus (strain Newman), a pigmented, waterborne pathogen of emerging concern. We measured photodecay using standard culture-based assays and cellular membrane integrity and investigated photostress response by measuring the relative number of mRNA transcripts of select oxidative stress, DNA repair, and metabolism genes. Photoinactivation experiments were performed in both oxic and anoxic systems to further investigate the role of oxygen-mediated and non-oxygen-mediated photoinactivation mechanisms. S. aureus lost culturability much faster in oxic systems than in anoxic systems, indicating an important role for oxygen in photodecay mechanisms. S. aureus cell membranes were damaged by sunlight exposure in anoxic systems but not in oxic systems, as measured by cell membrane permeability to propidium iodide. After sunlight exposure, S. aureus increased expression of a gene coding for methionine sulfoxide reductase after 12 h of sunlight exposure in the oxic system and after 6 h of sunlight exposure in the anoxic system, suggesting that methionine sulfoxide reductase is an important enzyme for defense against both oxygen-dependent and oxygen-independent photostresses. This research highlights the importance of oxygen in bacterial photoinactivation in environmentally relevant systems and the complexity of the bacterial photostress response with respect to cell structure and transcriptional regulation.IMPORTANCEStaphylococcus aureus is a pathogenic bacterium that causes gastrointestinal, respiratory, and skin infections. In severe cases, S. aureus infection can lead to life

  4. Role of toll-like receptors 3, 4 and 7 in cellular uptake and response to titanium dioxide nanoparticles

    Directory of Open Access Journals (Sweden)

    Peng Chen, Koki Kanehira and Akiyoshi Taniguchi

    2013-01-01

    Full Text Available Innate immune response is believed to be among the earliest provisional cellular responses, and mediates the interactions between microbes and cells. Toll-like receptors (TLRs are critical to these interactions. We hypothesize that TLRs also play an important role in interactions between nanoparticles (NPs and cells, although little information has been reported concerning such an interaction. In this study, we investigated the role of TLR3, TLR4 and TLR7 in cellular uptake of titanium dioxide NP (TiO2 NP agglomerates and the resulting inflammatory responses to these NPs. Our data indicate that TLR4 is involved in the uptake of TiO2 NPs and promotes the associated inflammatory responses. The data also suggest that TLR3, which has a subcellular location distinct from that of TLR4, inhibits the denaturation of cellular protein caused by TiO2 NPs. In contrast, the unique cellular localization of TLR7 has middle-ground functional roles in cellular response after TiO2 NP exposure. These findings are important for understanding the molecular interaction mechanisms between NPs and cells.

  5. Using an integrated approach to link biomarker responses and physiological stress to growth impairment of cadmium-exposed larval topsmelt

    Energy Technology Data Exchange (ETDEWEB)

    Rose, Wendy L. [Bodega Marine Laboratory, University of California Davis, Bodega Bay, CA 94923 (United States)]. E-mail: Wendy.Rose@WestonSolutions.com; Nisbet, Roger M. [Department of Ecology, Evolution, and Marine Biology, University of California Santa Barbara, Santa Barbara, CA 93106 (United States); Green, Peter G. [Department of Civil and Environmental Engineering, University of California Davis, Davis, CA 95616 (United States); Norris, Sarah [Department of Land, Air, and Water Resources, University of California Davis, Davis, CA 95616 (United States); Fan, Teresa [Department of Land, Air, and Water Resources, University of California Davis, Davis, CA 95616 (United States); Department of Chemistry, University of Louisville, Louisville, KY 40208 (United States); Smith, Edmund H. [Bodega Marine Laboratory, University of California Davis, Bodega Bay, CA 94923 (United States); Smith and Associates, Sebastopol, CA 95472 (United States); Cherr, Gary N. [Bodega Marine Laboratory, University of California Davis, Bodega Bay, CA 94923 (United States); Departments of Environmental Toxicology and Nutrition, University of California Davis, Davis, CA 95616 (United States); Anderson, Susan L. [Bodega Marine Laboratory, University of California Davis, Bodega Bay, CA 94923 (United States)

    2006-12-01

    In this study, we used an integrated approach to determine whether key biochemical, cellular, and physiological responses were related to growth impairment of cadmium (Cd)-exposed larval topsmelt (Atherinops affinis). Food intake (Artemia franciscana nauplii), oxygen consumption rates, apoptotic DNA fragmentation (TUNEL assay), and metallothionein (MT)-like protein levels, were separately measured in relation to growth of larval topsmelt aqueously exposed to sublethal doses of Cd for 14 days. Cadmium accumulation and concentrations of abundant metals were also evaluated in a subset of fish. Fish in the highest Cd treatments (50 and 100 ppb Cd) were smaller in final mean weight and length, and consumed fewer A. franciscana nauplii than control fish. Food intake was positively correlated with final weight of larval topsmelt in Cd and control treatments; food intake increased as final weight of the fish increased. Oxygen consumption rates were positively correlated with Cd concentration and mean oxygen consumption rates were inversely correlated with final mean weight of topsmelt; the smallest fish were found in the highest Cd treatment and were respiring at higher rates than control fish. Apoptotic DNA fragmentation was concentration-dependent and was associated with diminished growth. Apoptotic DNA fragmentation was elevated in the gill of fish exposed to 50 ppb Cd, and in the gut, gill, and liver of fish exposed to 100 ppb Cd. Metallothionein (MT)-like protein levels in fish from 100 ppb Cd treatments were significantly higher than those in other treatments. Oxygen consumption rates may have increased as a compensatory response to Cd exposure. However, it is likely that the energy produced was allocated to an increased metabolic demand due to apoptosis, MT synthesis, and changes in ion regulation. This diversion of energy expenditures could contribute to growth impairment of Cd-exposed fish.

  6. Identification of feedback loops embedded in cellular circuits by investigating non-causal impulse response components.

    Science.gov (United States)

    Dong, Chao-Yi; Yoon, Tae-Woong; Bates, Declan G; Cho, Kwang-Hyun

    2010-02-01

    Feedback circuits are crucial dynamic motifs which occur in many biomolecular regulatory networks. They play a pivotal role in the regulation and control of many important cellular processes such as gene transcription, signal transduction, and metabolism. In this study, we develop a novel computationally efficient method to identify feedback loops embedded in intracellular networks, which uses only time-series experimental data and requires no knowledge of the network structure. In the proposed approach, a non-parametric system identification technique, as well as a spectral factor analysis, is applied to derive a graphical criterion based on non-causal components of the system's impulse response. The appearance of non-causal components in the impulse response sequences arising from stochastic output perturbations is shown to imply the presence of underlying feedback connections within a linear network. In order to extend the approach to nonlinear networks, we linearize the intracellular networks about an equilibrium point, and then choose the magnitude of the output perturbations sufficiently small so that the resulting time-series responses remain close to the chosen equilibrium point. In this way, the impulse response sequences of the linearized system can be used to determine the presence or absence of feedback loops in the corresponding nonlinear network. The proposed method utilizes the time profile data from intracellular perturbation experiments and only requires the perturbability of output nodes. Most importantly, the method does not require any a priori knowledge of the system structure. For these reasons, the proposed approach is very well suited to identifying feedback loops in large-scale biomolecular networks. The effectiveness of the proposed method is illustrated via two examples: a synthetic network model with a negative feedback loop and a nonlinear caspase function model of apoptosis with a positive feedback loop.

  7. Cellular responses in sea fan corals: granular amoebocytes react to pathogen and climate stressors.

    Directory of Open Access Journals (Sweden)

    Laura D Mydlarz

    Full Text Available BACKGROUND: Climate warming is causing environmental change making both marine and terrestrial organisms, and even humans, more susceptible to emerging diseases. Coral reefs are among the most impacted ecosystems by climate stress, and immunity of corals, the most ancient of metazoans, is poorly known. Although coral mortality due to infectious diseases and temperature-related stress is on the rise, the immune effector mechanisms that contribute to the resistance of corals to such events remain elusive. In the Caribbean sea fan corals (Anthozoa, Alcyonacea: Gorgoniidae, the cell-based immune defenses are granular acidophilic amoebocytes, which are known to be involved in wound repair and histocompatibility. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate for the first time in corals that these cells are involved in the organismal response to pathogenic and temperature stress. In sea fans with both naturally occurring infections and experimental inoculations with the fungal pathogen Aspergillus sydowii, an inflammatory response, characterized by a massive increase of amoebocytes, was evident near infections. Melanosomes were detected in amoebocytes adjacent to protective melanin bands in infected sea fans; neither was present in uninfected fans. In naturally infected sea fans a concurrent increase in prophenoloxidase activity was detected in infected tissues with dense amoebocytes. Sea fans sampled in the field during the 2005 Caribbean Bleaching Event (a once-in-hundred-year climate event responded to heat stress with a systemic increase in amoebocytes and amoebocyte densities were also increased by elevated temperature stress in lab experiments. CONCLUSIONS/SIGNIFICANCE: The observed amoebocyte responses indicate that sea fan corals use cellular defenses to combat fungal infection and temperature stress. The ability to mount an inflammatory response may be a contributing factor that allowed the survival of even infected sea fan corals during a

  8. DNA-damage response network at the crossroads of cell-cycle checkpoints,cellular senescence and apoptosis

    Institute of Scientific and Technical Information of China (English)

    SCHMITT Estelle; PAQUET Claudie; BEAUCHEMIN Myriam; BERTRAND Richard

    2007-01-01

    Tissue homeostasis requires a carefully-orchestrated balance between cell proliferation,cellular senescence and cell death.Cells proliferate through a cell cycle that is tightly regulated by cyclin-dependent kinase activities.Cellular senescence is a safeguard program limiting the proliferative competence of cells in living organisms.Apoptosis eliminates unwanted cells by the coordinated activity of gene products that regulate and effect cell death.The intimate link between the cell cycle,cellular senescence,apoptosis regulation,cancer development and tumor responses to cancer treatment has become eminently apparent.Extensive research on tumor suppressor genes,oncogenes,the cell cycle and apoptosis regulatory genes has revealed how the DNA damage-sensing and -signaling pathways,referred to as the DNA-damage response network,are tied to cell proliferation,cell-cycle arrest,cellular senescence and apoptosis.DNA-damage responses are complex,involving "sensor" proteins that sense the damage,and transmit signals to "transducer" proteins,which,in turn,convey the signals to numerous "effector" proteins implicated in specific cellular pathways,including DNA repair mechanisms,cell-cycle checkpoints,cellular senescence and apoptosis.The Bcl-2 family of proteins stands among the most crucial regulators of apoptosis and performs vital functions in deciding whether a cell will live or die after cancer chemotherapy and irradiation.In addition,several studies have now revealed that members of the Bcl-2 family also interface with the cell cycle,DNA repair/recombination and cellular senescence,effects that are generally distinct from their function in apoptosis.In this review,we report progress in understanding the molecular networks that regulate cell-cycle checkpoints,cellular senescence and apoptosis after DNA damage,and discuss the influence of some Bcl-2 family members on cell-cycle checkpoint regulation.

  9. Activation of the cellular unfolded protein response by recombinant adeno-associated virus vectors.

    Directory of Open Access Journals (Sweden)

    Balaji Balakrishnan

    Full Text Available The unfolded protein response (UPR is a stress-induced cyto-protective mechanism elicited towards an influx of large amount of proteins in the endoplasmic reticulum (ER. In the present study, we evaluated if AAV manipulates the UPR pathways during its infection. We first examined the role of the three major UPR axes, namely, endoribonuclease inositol-requiring enzyme-1 (IRE1α, activating transcription factor 6 (ATF6 and PKR-like ER kinase (PERK in AAV infected cells. Total RNA from mock or AAV infected HeLa cells were used to determine the levels of 8 different ER-stress responsive transcripts from these pathways. We observed a significant up-regulation of IRE1α (up to 11 fold and PERK (up to 8 fold genes 12-48 hours after infection with self-complementary (scAAV2 but less prominent with single-stranded (ssAAV2 vectors. Further studies demonstrated that scAAV1 and scAAV6 also induce cellular UPR in vitro, with AAV1 vectors activating the PERK pathway (3 fold while AAV6 vectors induced a significant increase on all the three major UPR pathways [6-16 fold]. These data suggest that the type and strength of UPR activation is dependent on the viral capsid. We then examined if transient inhibition of UPR pathways by RNA interference has an effect on AAV transduction. siRNA mediated silencing of PERK and IRE1α had a modest effect on AAV2 and AAV6 mediated gene expression (∼1.5-2 fold in vitro. Furthermore, hepatic gene transfer of scAAV2 vectors in vivo, strongly elevated IRE1α and PERK pathways (2 and 3.5 fold, respectively. However, when animals were pre-treated with a pharmacological UPR inhibitor (metformin during scAAV2 gene transfer, the UPR signalling and its subsequent inflammatory response was attenuated concomitant to a modest 2.8 fold increase in transgene expression. Collectively, these data suggest that AAV vectors activate the cellular UPR pathways and their selective inhibition may be beneficial during AAV mediated gene transfer.

  10. Impaired Cellular Immunity in the Murine Neural Crest Conditional Deletion of Endothelin Receptor-B Model of Hirschsprung's Disease.

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    Ankush Gosain

    Full Text Available Hirschsprung's disease (HSCR is characterized by aganglionosis from failure of neural crest cell (NCC migration to the distal hindgut. Up to 40% of HSCR patients suffer Hirschsprung's-associated enterocolitis (HAEC, with an incidence that is unchanged from the pre-operative to the post-operative state. Recent reports indicate that signaling pathways involved in NCC migration may also be involved in the development of secondary lymphoid organs. We hypothesize that gastrointestinal (GI mucosal immune defects occur in HSCR that may contribute to enterocolitis. EdnrB was deleted from the neural crest (EdnrBNCC-/- resulting in mutants with defective NCC migration, distal colonic aganglionosis and the development of enterocolitis. The mucosal immune apparatus of these mice was interrogated at post-natal day (P 21-24, prior to histological signs of enterocolitis. We found that EdnrBNCC-/- display lymphopenia of their Peyer's Patches, the major inductive site of GI mucosal immunity. EdnrBNCC-/- Peyer's Patches demonstrate decreased B-lymphocytes, specifically IgM+IgDhi (Mature B-lymphocytes, which are normally activated and produce IgA following antigen presentation. EdnrBNCC-/- animals demonstrate decreased small intestinal secretory IgA, but unchanged nasal and bronchial airway secretory IgA, indicating a gut-specific defect in IgA production or secretion. In the spleen, which is the primary source of IgA-producing Mature B-lymphocytes, EdnrBNCC-/- animals display decreased B-lymphocytes, but an increase in Mature B-lymphocytes. EdnrBNCC-/- spleens are also small and show altered architecture, with decreased red pulp and a paucity of B-lymphocytes in the germinal centers and marginal zone. Taken together, these findings suggest impaired GI mucosal immunity in EdnrBNCC-/- animals, with the spleen as a potential site of the defect. These findings build upon the growing body of literature that suggests that intestinal defects in HSCR are not restricted

  11. Neuronal cellular responses to extremely low frequency electromagnetic field exposure: implications regarding oxidative stress and neurodegeneration.

    Science.gov (United States)

    Reale, Marcella; Kamal, Mohammad A; Patruno, Antonia; Costantini, Erica; D'Angelo, Chiara; Pesce, Miko; Greig, Nigel H

    2014-01-01

    Neurodegenerative diseases comprise both hereditary and sporadic conditions characterized by an identifying progressive nervous system dysfunction and distinctive neuopathophysiology. The majority are of non-familial etiology and hence environmental factors and lifestyle play key roles in their pathogenesis. The extensive use of and ever increasing worldwide demand for electricity has stimulated societal and scientific interest on the environmental exposure to low frequency electromagnetic fields (EMFs) on human health. Epidemiological studies suggest a positive association between 50/60-Hz power transmission fields and leukemia or lymphoma development. Consequent to the association between EMFs and induction of oxidative stress, concerns relating to development of neurodegenerative diseases, such as Alzheimer disease (AD), have been voiced as the brain consumes the greatest fraction of oxygen and is particularly vulnerable to oxidative stress. Exposure to extremely low frequency (ELF)-EMFs are reported to alter animal behavior and modulate biological variables, including gene expression, regulation of cell survival, promotion of cellular differentiation, and changes in cerebral blood flow in aged AD transgenic mice. Alterations in inflammatory responses have also been reported, but how these actions impact human health remains unknown. We hence evaluated the effects of an electromagnetic wave (magnetic field intensity 1 mT; frequency, 50-Hz) on a well-characterized immortalized neuronal cell model, human SH-SY5Y cells. ELF-EMF exposure elevated the expession of NOS and O2(-), which were countered by compensatory changes in antioxidant catylase (CAT) activity and enzymatic kinetic parameters related to CYP-450 and CAT activity. Actions of ELF-EMFs on cytokine gene expression were additionally evaluated and found rapidly modified. Confronted with co-exposure to H2O2-induced oxidative stress, ELF-EMF proved not as well counteracted and resulted in a decline in CAT

  12. Expression of cellular components in granulomatous inflammatory response in Piaractus mesopotamicus model.

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    Wilson Gómez Manrique

    Full Text Available The present study aimed to describe and characterize the cellular components during the evolution of chronic granulomatous inflammation in the teleost fish pacus (P. mesopotamicus induced by Bacillus Calmette-Guerin (BCG, using S-100, iNOS and cytokeratin antibodies. 50 fish (120±5.0 g were anesthetized and 45 inoculated with 20 μL (40 mg/mL (2.0 x 10(6 CFU/mg and five inoculated with saline (0,65% into muscle tissue in the laterodorsal region. To evaluate the inflammatory process, nine fish inoculated with BCG and one control were sampled in five periods: 3rd, 7th, 14th, 21st and 33rd days post-inoculation (DPI. Immunohistochemical examination showed that the marking with anti-S-100 protein and anti-iNOS antibodies was weak, with a diffuse pattern, between the third and seventh DPI. From the 14th to the 33rd day, the marking became stronger and marked the cytoplasm of the macrophages. Positivity for cytokeratin was initially observed in the 14th DPI, and the stronger immunostaining in the 33rd day, period in which the epithelioid cells were more evident and the granuloma was fully formed. Also after the 14th day, a certain degree of cellular organization was observed, due to the arrangement of the macrophages around the inoculated material, with little evidence of edema. The arrangement of the macrophages around the inoculum, the fibroblasts, the lymphocytes and, in most cases, the presence of melanomacrophages formed the granuloma and kept the inoculum isolated in the 33rd DPI. The present study suggested that the granulomatous experimental model using teleost fish P. mesopotamicus presented a similar response to those observed in mammals, confirming its importance for studies of chronic inflammatory reaction.

  13. Graphene oxide scaffold accelerates cellular proliferative response and alveolar bone healing of tooth extraction socket.

    Science.gov (United States)

    Nishida, Erika; Miyaji, Hirofumi; Kato, Akihito; Takita, Hiroko; Iwanaga, Toshihiko; Momose, Takehito; Ogawa, Kosuke; Murakami, Shusuke; Sugaya, Tsutomu; Kawanami, Masamitsu

    2016-01-01

    Graphene oxide (GO) consisting of a carbon monolayer has been widely investigated for tissue engineering platforms because of its unique properties. For this study, we fabricated a GO-applied scaffold and assessed the cellular and tissue behaviors in the scaffold. A preclinical test was conducted to ascertain whether the GO scaffold promoted bone induction in dog tooth extraction sockets. For this study, GO scaffolds were prepared by coating the surface of a collagen sponge scaffold with 0.1 and 1 µg/mL GO dispersion. Scaffolds were characterized using scanning electron microscopy (SEM), physical testing, cell seeding, and rat subcutaneous implant testing. Then a GO scaffold was implanted into a dog tooth extraction socket. Histological observations were made at 2 weeks postsurgery. SEM observations show that GO attached to the surface of collagen scaffold struts. The GO scaffold exhibited an interconnected structure resembling that of control subjects. GO application improved the physical strength, enzyme resistance, and adsorption of calcium and proteins. Cytocompatibility tests showed that GO application significantly increased osteoblastic MC3T3-E1 cell proliferation. In addition, an assessment of rat subcutaneous tissue response revealed that implantation of 1 µg/mL GO scaffold stimulated cellular ingrowth behavior, suggesting that the GO scaffold exhibited good biocompatibility. The tissue ingrowth area and DNA contents of 1 µg/mL GO scaffold were, respectively, approximately 2.5-fold and 1.4-fold greater than those of the control. Particularly, the infiltration of ED2-positive (M2) macrophages and blood vessels were prominent in the GO scaffold. Dog bone-formation tests showed that 1 µg/mL GO scaffold implantation enhanced bone formation. New bone formation following GO scaffold implantation was enhanced fivefold compared to that in control subjects. These results suggest that GO was biocompatible and had high bone-formation capability for the scaffold

  14. Cellular stress response in Eca-109 cells inhibits apoptosis during early exposure to isorhamnetin.

    Science.gov (United States)

    Shi, C; Fan, L Y; Cai, Z; Liu, Y Y; Yang, C L

    2012-01-01

    The flavonol aglycone isorhamnetin shows anti-proliferative activity in a variety of cancer cells. Previous work, from our laboratory showed that isorhamnetin inhibits the proliferation of human esophageal squamous carcinoma Eca-109 cells in vitro, but only after 72 h of exposure. This led us to propose that isorhamnetin exposure induces a cellular stress response that inhibits the antiproliferative and apoptotic effects of the compound during early exposure. To test this hypothesis, the present study examined the effects of isorhamnetin on Eca-109 cells during the first 72 h of exposure. Cell growth was assessed using the trypan blue exclusion assay, and expression of IκBα, NF-κB/p65, NF-κB/p50, phospho-Akt, Bcl-2, COX-2, Mcl-1, Bax, p53 and Id-1 were analyzed by Western blot. During the first 72 h of exposure, NF-κB/p65 and NF-κB/p50 accumulated in nuclei and expression of COX-2, Bcl-2 and Mcl-1 increased. In contrast, expression of IκBα and Bax fell initially but later increased. Expression of phospho-Akt and p53 showed no detectable change during the first 48 h. Pretreatment with the NF-κB inhibitor MG132 before exposure to isorhamnetin blocked the nuclear accumulation of p50 and p65, thereby inhibiting cell proliferation. These results show that during early exposure of Eca-109 cells to isorhamnetin, the NF-κB signaling pathway is activated and COX-2 expression increases, and this increase in expression partially inhibits isorhamnetin-induced apoptosis. Beyond 72 h of exposure, however, the apoptotic effect of isorhamnetin dominates, leading to inhibition of the NF-κB pathway and of cellular proliferation. These results will need to be taken into account when exploring the use of isorhamnetin against cancer in vivo.

  15. Effects of dietary conjugated linoleic acids on cellular immune response of piglets after cyclosporin A injection.

    Science.gov (United States)

    Liu, Y X; Zhu, K Y; Liu, Y L; Jiang, D F

    2016-10-01

    The present study investigated the effects of dietary conjugated linoleic acid (CLA) on the cellular immune response of piglets after cyclosporin A (CsA) treatment. The experimental study had a 2×2 factorial design, and the main factors consisted of diets (0% or 2% CLA) and immunosuppression treatments (CsA or saline injection). CsA injection significantly increased feed : gain (F : G) of piglets (P<0.05); however, dietary CLA significantly decreased F : G of piglets (P<0.05). Dietary CLA partly ameliorated the deterioration of the feed conversion rate caused by CsA treatment (P<0.01). CsA treatment significantly decreased the percentages of CD4+ and CD8+ T lymphocytes in the thymus (P<0.01). Dietary CLA increased the percentages of CD4+ CD8+ double-positive and CD8+ single-positive T lymphocytes in the thymus (P<0.05), and had the trend to inhibit the decrease of CD4+ T lymphocytes in the thymus after CsA injection (P=0.07). CsA treatment significantly depleted the peripheral blood CD3+, CD4+ and CD8+ T lymphocytes (P<0.01). Dietary CLA significantly increased the number of peripheral blood CD8+ T lymphocytes and interleukin-2 (IL-2) production (P<0.05), and inhibited the decreases of peripheral blood CD3+, CD4+ and CD8+ T lymphocytes counts (P<0.01) as well as IL-2 production (P<0.05) after CsA treatment. Dietary CLA partly rescued the decrease of lymphocyte proliferation after CsA injection (P<0.05). In summary, dietary CLA effectively ameliorated CsA-induced cellular immunosuppression in piglets.

  16. Molecular deconstruction, detection, and computational prediction of microenvironment-modulated cellular responses to cancer therapeutics.

    Science.gov (United States)

    Labarge, Mark A; Parvin, Bahram; Lorens, James B

    2014-04-01

    The field of bioengineering has pioneered the application of new precision fabrication technologies to model the different geometric, physical or molecular components of tissue microenvironments on solid-state substrata. Tissue engineering approaches building on these advances are used to assemble multicellular mimetic-tissues where cells reside within defined spatial contexts. The functional responses of cells in fabricated microenvironments have revealed a rich interplay between the genome and extracellular effectors in determining cellular phenotypes and in a number of cases have revealed the dominance of microenvironment over genotype. Precision bioengineered substrata are limited to a few aspects, whereas cell/tissue-derived microenvironments have many undefined components. Thus, introducing a computational module may serve to integrate these types of platforms to create reasonable models of drug responses in human tissues. This review discusses how combinatorial microenvironment microarrays and other biomimetic microenvironments have revealed emergent properties of cells in particular microenvironmental contexts, the platforms that can measure phenotypic changes within those contexts, and the computational tools that can unify the microenvironment-imposed functional phenotypes with underlying constellations of proteins and genes. Ultimately we propose that a merger of these technologies will enable more accurate pre-clinical drug discovery. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Adaptive endoplasmic reticulum stress alters cellular responses to the extracellular milieu.

    Science.gov (United States)

    Liu, Yiting; Neely, Elizabeth; Simmons, Zachary; Connor, James R

    2015-05-01

    The ability to respond to perturbations in endoplasmic reticulum (ER) function is a critical property for all cells. In the presence of chronic ER stress, the cell must adapt so that cell survival is favored or the stress may promote apoptosis. In some pathological processes, such as neurodengeneration, persistent ER stress can be tolerated for an extended period, but eventually cell death occurs. It is not known how an adaptive response converts from survival into apoptosis. To gain a better understanding of the role of adaptive ER stress in neurodegeneration, in this study, with a neuronal cell line SH-SY5Y and primary motor neuron-glia cell mixed cultures, we induced adaptive ER stress and modified the extracellular environment with physiologically relevant changes that alone did not activate ER stress. Our data demonstrate that an adaptive ER stress favored neuronal cell survival, but when cells were exposed to additional physiological insults the level of ER stress was increased, followed by activation of the caspase pathway. Our results indicate that an adaptive ER stress response could be converted to apoptosis when the external cellular milieu changed, suggesting that the conversion from prosurvival to proapoptotic pathways can be driven by the external milieu. This conversion was due at least partially to an increased level of ER stress. © 2015 Wiley Periodicals, Inc.

  18. Cellular responses during morphological transformation in Azospirillum brasilense and Its flcA knockout mutant.

    Directory of Open Access Journals (Sweden)

    Xingsheng Hou

    Full Text Available FlcA is a response regulator controlling flocculation and the morphological transformation of Azospirillum cells from vegetative to cyst-like forms. To understand the cellular responses of Azospirillum to conditions that cause morphological transformation, proteins differentially expressed under flocculation conditions in A. brasilense Sp7 and its flcA knockout mutant were investigated. Comparison of 2-DE protein profiles of wild-type (Sp7 and a flcA deletion mutant (Sp7-flcAΔ revealed a total of 33 differentially expressed 2-DE gel spots, with 22 of these spots confidently separated to allow protein identification. Analysis of these spots by liquid chromatography-tandem mass spectrometry (LC-MS/MS and MASCOT database searching identified 48 proteins (≥10% emPAI in each spot. The functional characteristics of these proteins included carbon metabolism (beta-ketothiolase and citrate synthase, nitrogen metabolism (Glutamine synthetase and nitric oxide synthase, stress tolerance (superoxide dismutase, Alkyl hydroperoxidase and ATP-dependent Clp protease proteolytic subunit and morphological transformation (transducer coupling protein. The observed differences between Sp7 wild-type and flcA- strains enhance our understanding of the morphological transformation process and help to explain previous phenotypical observations. This work is a step forward in connecting the Azospirillum phenome and genome.

  19. Microfluidic chips for in vivo imaging of cellular responses to neural injury in Drosophila larvae.

    Directory of Open Access Journals (Sweden)

    Mostafa Ghannad-Rezaie

    Full Text Available With powerful genetics and a translucent cuticle, the Drosophila larva is an ideal model system for live imaging studies of neuronal cell biology and function. Here, we present an easy-to-use approach for high resolution live imaging in Drosophila using microfluidic chips. Two different designs allow for non-invasive and chemical-free immobilization of 3(rd instar larvae over short (up to 1 hour and long (up to 10 hours time periods. We utilized these 'larva chips' to characterize several sub-cellular responses to axotomy which occur over a range of time scales in intact, unanaesthetized animals. These include waves of calcium which are induced within seconds of axotomy, and the intracellular transport of vesicles whose rate and flux within axons changes dramatically within 3 hours of axotomy. Axonal transport halts throughout the entire distal stump, but increases in the proximal stump. These responses precede the degeneration of the distal stump and regenerative sprouting of the proximal stump, which is initiated after a 7 hour period of dormancy and is associated with a dramatic increase in F-actin dynamics. In addition to allowing for the study of axonal regeneration in vivo, the larva chips can be utilized for a wide variety of in vivo imaging applications in Drosophila.

  20. Signaling beyond Punching Holes: Modulation of Cellular Responses by Vibrio cholerae Cytolysin

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    Barkha Khilwani

    2015-08-01

    Full Text Available Pore-forming toxins (PFTs are a distinct class of membrane-damaging cytolytic proteins that contribute significantly towards the virulence processes employed by various pathogenic bacteria. Vibrio cholerae cytolysin (VCC is a prominent member of the beta-barrel PFT (beta-PFT family. It is secreted by most of the pathogenic strains of the intestinal pathogen V. cholerae. Owing to its potent membrane-damaging cell-killing activity, VCC is believed to play critical roles in V. cholerae pathogenesis, particularly in those strains that lack the cholera toxin. Large numbers of studies have explored the mechanistic basis of the cell-killing activity of VCC. Consistent with the beta-PFT mode of action, VCC has been shown to act on the target cells by forming transmembrane oligomeric beta-barrel pores, thereby leading to permeabilization of the target cell membranes. Apart from the pore-formation-induced direct cell-killing action, VCC exhibits the potential to initiate a plethora of signal transduction pathways that may lead to apoptosis, or may act to enhance the cell survival/activation responses, depending on the type of target cells. In this review, we will present a concise view of our current understanding regarding the multiple aspects of these cellular responses, and their underlying signaling mechanisms, evoked by VCC.

  1. Cellular model for studying accommodation to environmental stressors: a protective response to subtoxic exposure to cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Chin, B.; Lesowitz, G.S.; Bernstein, I.A.; Dinman, B.D.

    1978-01-01

    A model is described for testing the effect of exposure to subtoxic challenge upon cellular integrity. The model incorporates Physarum polycephalum as a biological assay system, the ability of the cell to traverse the cell cycle as an indicator of cell integrity, and the use of repeated challenge by cadmium ion as a mechanism for amplifying the response to subthreshold exposure. A sensitivity profile of Physarum, developed by periodic exposure to 5 x 10/sup -4/ M Cd/sup 2 +/ for 30 min throughout the cell cycle, contains two peaks of sensitivity resulting in mitotic delay, one in early S and the other in late G/sub 2/. Physarum accommodates to a subtoxic challenge of Cd/sup 2 +/ by developing a protective response: Exposure to 10/sup -4/ M Cd/sup 2 +/ for 30 min in early G/sub 2/ (0.45 cycle), which does not delay mitosis, protects Physarum against a mitotic delay of 105 min resulting from exposure to 4 x 10/sup -4/ M Cd/sup 2 +/ for 30 min in late G/sub 2/ (0.75 cycle). Protection persists for at least two cell cycles.

  2. The adaptor protein FHL2 enhances the cellular innate immune response to influenza A virus infection.

    Science.gov (United States)

    Nordhoff, Carolin; Hillesheim, Andrea; Walter, Beate M; Haasbach, Emanuel; Planz, Oliver; Ehrhardt, Christina; Ludwig, Stephan; Wixler, Viktor

    2012-07-01

    The innate immune response of influenza A virus-infected cells is predominantly mediated by type I interferon-induced proteins. Expression of the interferon β (IFNβ) itself is initiated by accumulating viral RNA and is transmitted by different signalling cascades that feed into activation of the three transcriptional elements located in the IFNβ promoter, AP-1, IRF-3 and NF-κB. FHL2 (four-and-a-half LIM domain protein 2) is an adaptor molecule that shuttles between membrane and nucleus regulating signalling cascades and gene transcription. Here we describe FHL2 as a novel regulator of influenza A virus propagation. Using mouse FHL2 wild-type, knockout and rescued cells and human epithelial cells with different expression levels of FHL2 we showed that FHL2 decreases influenza A virus propagation by regulating the intrinsic cellular antiviral immune response. On virus infection FHL2 translocates into the nucleus, potentiating the IRF-3-dependent transcription of the IFNβ gene.

  3. Toxicity of silver nanoparticles in human macrophages: uptake, intracellular distribution and cellular responses

    Energy Technology Data Exchange (ETDEWEB)

    Haase, A; Tentschert, J; Jungnickel, H; Goetz, M E; Luch, A [BfR - Federal Institute for Risk Assessment, Department of Product Safety, Thielallee 88-92, 14195 Berlin (Germany); Graf, P [University of Basel, Department of Chemistry, Klingelbergstrasse 80, 4056 Basel (Switzerland); Mantion, A; Thuenemann, A F [BAM - Federal Institute for Materials Research and Testing, Richard-Willstaetter-Strasse 11, 12489 Berlin (Germany); Draude, F; Galla, S; Arlinghaus, H F [University of Muenster, Institute of Physics, Wilhelm Klemm Strasse 10, 48149 Muenster (Germany); Plendl, J [Free University of Berlin, Department of Veterinary Medicine, Institute of Veterinary Anatomy, Koserstrasse 20, 14195 Berlin (Germany); Masic, A; Taubert, A, E-mail: andrea.haase@bfr.bund.de, E-mail: alexandre.mantion@bam.de [University of Potsdam, Institute of Chemistry, Karl- Liebknecht- Strasse 24-25, 14476 Potsdam-Golm (Germany)

    2011-07-06

    Silver nanoparticles (SNP) are among the most commercialized nanoparticles worldwide. They can be found in many diverse products, mostly because of their antibacterial properties. Despite its widespread use only little data on possible adverse health effects exist. It is difficult to compare biological data from different studies due to the great variety in sizes, coatings or shapes of the particles. Here, we applied a novel synthesis approach to obtain SNP, which are covalently stabilized by a small peptide. This enables a tight control of both size and shape. We applied these SNP in two different sizes of 20 or 40 nm (Ag20Pep and Ag40Pep) and analyzed responses of THP-1-derived human macrophages. Similar gold nanoparticles with the same coating (Au20Pep) were used for comparison and found to be non-toxic. We assessed the cytotoxicity of particles and confirmed their cellular uptake via transmission electron microscopy and confocal Raman microscopy. Importantly a majority of the SNP could be detected as individual particles spread throughout the cells. Furthermore we studied several types of oxidative stress related responses such as induction of heme oxygenase I or formation of protein carbonyls. In summary, our data demonstrate that even low doses of SNP exerted adverse effects in human macrophages.

  4. Metal oxide nanoparticles interact with immune cells and activate different cellular responses

    Directory of Open Access Journals (Sweden)

    Simón-Vázquez R

    2016-09-01

    Full Text Available Rosana Simón-Vázquez, Tamara Lozano-Fernández, Angela Dávila-Grana, Africa González-Fernández Immunology Laboratory, Biomedical Research Center (CINBIO and Institute of Biomedical Research of Ourense-Pontevedra-Vigo (IBI, University of Vigo, Campus Lagoas Marcosende, Vigo, Pontevedra, Spain Abstract: Besides cell death, nanoparticles (Nps can induce other cellular responses such as inflammation. The potential immune response mediated by the exposure of human lymphoid cells to metal oxide Nps (moNps was characterized using four different moNps (CeO2, TiO2, Al2O3, and ZnO to study the three most relevant mitogen-activated protein kinase subfamilies and the nuclear factor kappa-light-chain-enhancer of the activated B-cell inhibitor, IκBα, as well as the expression of several genes by immune cells incubated with these Nps. The moNps activated different signaling pathways and altered the gene expression in human lymphocyte cells. The ZnO Nps were the most active and the release of Zn2+ ions was the main mechanism of toxicity. CeO2 Nps induced the smallest changes in gene expression and in the IκBα protein. The effects of the particles were strongly dependent on the type and concentration of the Nps and on the cell activation status prior to Np exposure. Keywords: Jurkat, MAPK, NFκB, qPCR, inflammation, metabolism

  5. Cellular and humoral antibody responses of normal pastel and sapphire mink to goat erythrocytes.

    Science.gov (United States)

    Lodmell, D L; Bergman, R K; Hadlow, W J; Munoz, J J

    1971-02-01

    This study was undertaken to determine whether normal sapphire and royal pastel mink differ immunologically at the cellular and humoral levels. Two days after primary intraperitoneal (ip) inoculation of goat erythrocytes (GE), essentially no 19 or 7S plaque-forming cells (PFC) per 10(6) cells were detected in spleen or in abdominal and peripheral lymph nodes of either color phase. On the 4th day, more 19S PFC were detected in pastel than in sapphire tissues; pastel tissues also contained 7S PFC, whereas essentially none was present in sapphires until the 6th day. After an ip booster inoculation, the number of PFC was markedly different between the two color phases. These differences were most apparent in spleen and peripheral lymph nodes. In parallel with differences observed in PFC responses between the color phases, total hemolysin and 2-mercaptoethanol-resistant hemolysin titers of pastels exceeded those of sapphires in all but one interval after the primary, and at every interval after the booster, inoculation. These data indicate that sapphire mink are not immunological cripples, nor are they immunologically hyperactive, but that differences do exist between sapphire and royal pastel mink, especially in the response to booster injections of GE.

  6. Cellular responses during morphological transformation in Azospirillum brasilense and Its flcA knockout mutant.

    Science.gov (United States)

    Hou, Xingsheng; McMillan, Mary; Coumans, Joëlle V F; Poljak, Anne; Raftery, Mark J; Pereg, Lily

    2014-01-01

    FlcA is a response regulator controlling flocculation and the morphological transformation of Azospirillum cells from vegetative to cyst-like forms. To understand the cellular responses of Azospirillum to conditions that cause morphological transformation, proteins differentially expressed under flocculation conditions in A. brasilense Sp7 and its flcA knockout mutant were investigated. Comparison of 2-DE protein profiles of wild-type (Sp7) and a flcA deletion mutant (Sp7-flcAΔ) revealed a total of 33 differentially expressed 2-DE gel spots, with 22 of these spots confidently separated to allow protein identification. Analysis of these spots by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and MASCOT database searching identified 48 proteins (≥10% emPAI in each spot). The functional characteristics of these proteins included carbon metabolism (beta-ketothiolase and citrate synthase), nitrogen metabolism (Glutamine synthetase and nitric oxide synthase), stress tolerance (superoxide dismutase, Alkyl hydroperoxidase and ATP-dependent Clp protease proteolytic subunit) and morphological transformation (transducer coupling protein). The observed differences between Sp7 wild-type and flcA- strains enhance our understanding of the morphological transformation process and help to explain previous phenotypical observations. This work is a step forward in connecting the Azospirillum phenome and genome.

  7. Cyclophilin 20-3 relays a 12-oxo-phytodienoic acid signal during stress responsive regulation of cellular redox homeostasis.

    Science.gov (United States)

    Park, Sang-Wook; Li, Wei; Viehhauser, Andrea; He, Bin; Kim, Soonok; Nilsson, Anders K; Andersson, Mats X; Kittle, Joshua D; Ambavaram, Madana M R; Luan, Sheng; Esker, Alan R; Tholl, Dorothea; Cimini, Daniela; Ellerström, Mats; Coaker, Gitta; Mitchell, Thomas K; Pereira, Andy; Dietz, Karl-Josef; Lawrence, Christopher B

    2013-06-04

    The jasmonate family of phytohormones plays central roles in plant development and stress acclimation. However, the architecture of their signaling circuits remains largely unknown. Here we describe a jasmonate family binding protein, cyclophilin 20-3 (CYP20-3), which regulates stress-responsive cellular redox homeostasis. (+)-12-Oxo-phytodienoic acid (OPDA) binding promotes CYP20-3 to form a complex with serine acetyltransferase 1, which triggers the formation of a hetero-oligomeric cysteine synthase complex with O-acetylserine(thiol)lyase B in chloroplasts. The cysteine synthase complex formation then activates sulfur assimilation that leads to increased levels of thiol metabolites and the buildup of cellular reduction potential. The enhanced redox capacity in turn coordinates the expression of a subset of OPDA-responsive genes. Thus, we conclude that CYP20-3 is a key effector protein that links OPDA signaling to amino acid biosynthesis and cellular redox homeostasis in stress responses.

  8. Integrative analysis of miRNA and mRNA paired expression profiling of primary fibroblast derived from diabetic foot ulcers reveals multiple impaired cellular functions.

    Science.gov (United States)

    Liang, Liang; Stone, Rivka C; Stojadinovic, Olivera; Ramirez, Horacio; Pastar, Irena; Maione, Anna G; Smith, Avi; Yanez, Vanessa; Veves, Aristides; Kirsner, Robert S; Garlick, Jonathan A; Tomic-Canic, Marjana

    2016-11-01

    Diabetic foot ulcers (DFUs) are one of the major complications of diabetes. Its molecular pathology remains poorly understood, impeding the development of effective treatments. Although it has been established that multiple cell types, including fibroblasts, keratinocytes, macrophages, and endothelial cells, all contribute to inhibition of healing, less is known regarding contributions of individual cell type. Thus, we generated primary fibroblasts from nonhealing DFUs and evaluated their cellular and molecular properties in comparison to nondiabetic foot fibroblasts (NFFs). Specifically, we analyzed both micro-RNA and mRNA expression profiles of primary DFU fibroblasts. Paired genomic analyses identified a total of 331 reciprocal miRNA-mRNA pairs including 21 miRNAs (FC > 2.0) along with 239 predicted target genes (FC > 1.5) that are significantly and differentially expressed. Of these, we focused on three miRNAs (miR-21-5p, miR-34a-5p, miR-145-5p) that were induced in DFU fibroblasts as most differentially regulated. The involvement of these microRNAs in wound healing was investigated by testing the expression of their downstream targets as well as by quantifying cellular behaviors in prospectively collected and generated cell lines from 15 patients (seven DFUF and eight NFF samples). We found large number of downstream targets of miR-21-5p, miR-34a-5p, miR-145-5p to be coordinately regulated in mRNA profiles, which was confirmed by quantitative real-time PCR. Pathway analysis on paired miRNA-mRNA profiles predicted inhibition of cell movement and cell proliferation, as well as activation of cell differentiation and senescence in DFU fibroblasts, which was confirmed by cellular assays. We concluded that induction of miR-21-5p, miR-34a-5p, miR-145-5p in DFU dermal fibroblasts plays an important role in impairing multiple cellular functions, thus contributing to overall inhibition of healing in DFUs.

  9. The relationship between visual orienting responses and clinical characteristics in children attending special education for the visually impaired.

    Science.gov (United States)

    Kooiker, Marlou J G; Pel, Johan J M; van der Steen, Johannes

    2015-05-01

    We recently introduced a method based on quantification of orienting responses toward visual stimuli to assess the quality of visual information processing in children. In the present study, we examined the relationship between orienting responses and factors that are associated with visual processing impairments in current clinical practice. Response time and fixation quality to visual features such as form, contrast, motion, and color stimuli were assessed in 104 children from 1 to 12 years attending special education for the visually impaired. Using regression analysis, we investigated whether these parameters were affected by clinical characteristics of children. Response times significantly depended on stimulus type. Responses to high-contrast cartoons were significantly slower in children with a clinical diagnosis of cerebral visual impairment. Fixation quality was significantly affected by visual acuity and nystagmus. The results suggest that the quantitative measurement of orienting responses is strongly related to cerebral visual impairment in children.

  10. NR4A2 is regulated by gastrin and influences cellular responses of gastric adenocarcinoma cells.

    Directory of Open Access Journals (Sweden)

    Kristine Misund

    Full Text Available The peptide hormone gastrin is known to play a role in differentiation, growth and apoptosis of cells in the gastric mucosa. In this study we demonstrate that gastrin induces Nuclear Receptor 4A2 (NR4A2 expression in the adenocarcinoma cell lines AR42J and AGS-GR, which both possess the gastrin/CCK2 receptor. In vivo, NR4A2 is strongly expressed in the gastrin responsive neuroendocrine ECL cells in normal mucosa, whereas gastric adenocarcinoma tissue reveals a more diffuse and variable expression in tumor cells. We show that NR4A2 is a primary early transient gastrin induced gene in adenocarcinoma cell lines, and that NR4A2 expression is negatively regulated by inducible cAMP early repressor (ICER and zinc finger protein 36, C3H1 type-like 1 (Zfp36l1, suggesting that these gastrin regulated proteins exert a negative feedback control of NR4A2 activated responses. FRAP analyses indicate that gastrin also modifies the nucleus-cytosol shuttling of NR4A2, with more NR4A2 localized to cytoplasm upon gastrin treatment. Knock-down experiments with siRNA targeting NR4A2 increase migration of gastrin treated adenocarcinoma AGS-GR cells, while ectopically expressed NR4A2 increases apoptosis and hampers gastrin induced invasion, indicating a tumor suppressor function of NR4A2. Collectively, our results uncover a role of NR4A2 in gastric adenocarcinoma cells, and suggest that both the level and the localization of NR4A2 protein are of importance regarding the cellular responses of these cells.

  11. Space experiment "Cellular Responses to Radiation in Space (CellRad)": Hardware and biological system tests.

    Science.gov (United States)

    Hellweg, Christine E; Dilruba, Shahana; Adrian, Astrid; Feles, Sebastian; Schmitz, Claudia; Berger, Thomas; Przybyla, Bartos; Briganti, Luca; Franz, Markus; Segerer, Jürgen; Spitta, Luis F; Henschenmacher, Bernd; Konda, Bikash; Diegeler, Sebastian; Baumstark-Khan, Christa; Panitz, Corinna; Reitz, Günther

    2015-11-01

    One factor contributing to the high uncertainty in radiation risk assessment for long-term space missions is the insufficient knowledge about possible interactions of radiation with other spaceflight environmental factors. Such factors, e.g. microgravity, have to be considered as possibly additive or even synergistic factors in cancerogenesis. Regarding the effects of microgravity on signal transduction, it cannot be excluded that microgravity alters the cellular response to cosmic radiation, which comprises a complex network of signaling pathways. The purpose of the experiment "Cellular Responses to Radiation in Space" (CellRad, formerly CERASP) is to study the effects of combined exposure to microgravity, radiation and general space flight conditions on mammalian cells, in particular Human Embryonic Kidney (HEK) cells that are stably transfected with different plasmids allowing monitoring of proliferation and the Nuclear Factor κB (NF-κB) pathway by means of fluorescent proteins. The cells will be seeded on ground in multiwell plate units (MPUs), transported to the ISS, and irradiated by an artificial radiation source after an adaptation period at 0 × g and 1 × g. After different incubation periods, the cells will be fixed by pumping a formaldehyde solution into the MPUs. Ground control samples will be treated in the same way. For implementation of CellRad in the Biolab on the International Space Station (ISS), tests of the hardware and the biological systems were performed. The sequence of different steps in MPU fabrication (cutting, drilling, cleaning, growth surface coating, and sterilization) was optimized in order to reach full biocompatibility. Different coatings of the foil used as growth surface revealed that coating with 0.1 mg/ml poly-D-lysine supports cell attachment better than collagen type I. The tests of prototype hardware (Science Model) proved its full functionality for automated medium change, irradiation and fixation of cells. Exposure of

  12. Space experiment "Cellular Responses to Radiation in Space (CELLRAD)": Hardware and biological system tests

    Science.gov (United States)

    Hellweg, Christine E.; Dilruba, Shahana; Adrian, Astrid; Feles, Sebastian; Schmitz, Claudia; Berger, Thomas; Przybyla, Bartos; Briganti, Luca; Franz, Markus; Segerer, Jürgen; Spitta, Luis F.; Henschenmacher, Bernd; Konda, Bikash; Diegeler, Sebastian; Baumstark-Khan, Christa; Panitz, Corinna; Reitz, Günther

    2015-11-01

    One factor contributing to the high uncertainty in radiation risk assessment for long-term space missions is the insufficient knowledge about possible interactions of radiation with other spaceflight environmental factors. Such factors, e.g. microgravity, have to be considered as possibly additive or even synergistic factors in cancerogenesis. Regarding the effects of microgravity on signal transduction, it cannot be excluded that microgravity alters the cellular response to cosmic radiation, which comprises a complex network of signaling pathways. The purpose of the experiment "Cellular Responses to Radiation in Space" (CELLRAD, formerly CERASP) is to study the effects of combined exposure to microgravity, radiation and general space flight conditions on mammalian cells, in particular Human Embryonic Kidney (HEK) cells that are stably transfected with different plasmids allowing monitoring of proliferation and the Nuclear Factor κB (NF-κB) pathway by means of fluorescent proteins. The cells will be seeded on ground in multiwell plate units (MPUs), transported to the ISS, and irradiated by an artificial radiation source after an adaptation period at 0 × g and 1 × g. After different incubation periods, the cells will be fixed by pumping a formaldehyde solution into the MPUs. Ground control samples will be treated in the same way. For implementation of CELLRAD in the Biolab on the International Space Station (ISS), tests of the hardware and the biological systems were performed. The sequence of different steps in MPU fabrication (cutting, drilling, cleaning, growth surface coating, and sterilization) was optimized in order to reach full biocompatibility. Different coatings of the foil used as growth surface revealed that coating with 0.1 mg/ml poly-D-lysine supports cell attachment better than collagen type I. The tests of prototype hardware (Science Model) proved its full functionality for automated medium change, irradiation and fixation of cells. Exposure of

  13. Cognitive impairment predicts worse short-term response to spinal tap test in normal pressure hydrocephalus.

    Science.gov (United States)

    Wolfsegger, Thomas; Topakian, Raffi

    2017-08-15

    In patients with idiopathic normal pressure hydrocephalus (iNPH), the spinal tap test (STT) is commonly used to predict ventriculoperitoneal shunt responsiveness. Clinical improvement following STT usually is measured by testing gait function. In our study, we investigated the impact of cognitive impairment on gait improvement after STT. 22 patients with the clinical and radiological diagnosis of iNPH underwent gait analyses (mobile measuring system Medilogic) before and 2-4h after STT in self-paced gait velocity over 7m. Prior to STT, cognition was evaluated by the Mini Mental State Examination (MMSE). MMSESTT vs. after STT were analyzed with ANOVA with repeated measures. 1. Baseline gait parameters did not differ between the two groups: patients with iNPH and normal cognition (n=11) and patients with iNPH-CI (n=11). 2. Following STT, there was significant improvement of gait parameters in patients without cognitive impairment, while patients with iNPH-CI did not benefit from STT. Subjects with iNPH have a higher probability of lack of gait improvement 2-4h following STT, if cognitive impairment is present. Further studies are needed to elucidate the associations of cognitive impairment and quantitative gait parameters measured early and at later time points after STT. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. The molecular and cellular response of normal and progressed human bronchial epithelial cells to HZE particles

    Science.gov (United States)

    Story, Michael; Ding, Liang-Hao; Minna, John; Park, Seong-mi; Larsen, Jill

    We have used a model of non-oncogenically immortalized normal human bronchial epithelial cells to determine the response of such cells to particles found outside the protection of the earth’s electromagnetic field. We have identified an enhanced frequency of cellular transformation, as measured by growth in soft agar, for both 56Fe and 28Si (1 GeV/n) that is maximal (4-6 fold) at 0.25 Gy and 0.40 Gy, respectively. At 4 months post-irradiation 38 individual soft agar clones were isolated. These clones were characterized extensively for cellular and molecular changes. Gene expression analysis suggested that these clones had down-regulated several genes associated with anti-oxidant pathways including GLS2, GPX1 and 4, SOD2, PIG3, and NQO1 amongst others. As a result, many of these transformed clones were exposed to high levels of intracellular radical oxygen species (ROS), although there appeared not to be any enhanced mitochondrial ROS. DNA repair pathways associated with ATM/ATR signaling were also upregulated. However, these transformants do not develop into tumors when injected into immune-compromised mice, suggesting that they have not progressed sufficiently to become oncogenic. Therefore we chose 6 soft agar clones for continuous culture for an additional 14 months. Amongst the 6 clones, only one clone showed any significant change in phenotype. Clone 3kt-ff.2a, propagated for 18 months, were 2-fold more radioresistant, had a shortened doubling time and the background rate of transformation more than doubled. Furthermore, the morphology of transformed clones changed. Clones from this culture are being compared to the original clone as well as the parental HBEC3KT and will be injected into immune-compromised mice for oncogenic potential. Oncogenically progressed HBECs, HBEC3KT cells that overexpress a mutant RAS gene and where p53 has been knocked down, designated HBEC3KTR53, responded quite differently to HZE particle exposure. First, these cells are more

  15. Assessment of the cellular and electrophysiological response of cardiomyocytes to radiation

    Science.gov (United States)

    Helm, Alexander; Ritter, Sylvia; Durante, Marco; Friess, Johannes; Thielemann, Christiane; Mr; Frank, Simon

    Cardiac disease is considered as a late effect resulting from an exposure during long-term space missions. Yet, the underlying mechanisms and the impact of radiation quality and dose are not well understood. To address this topic, we used cardiomyocytes derived from mouse embryonic stem cells (mESC) as a model system. This model has already been successfully used for cardiotoxicity screening of new drugs. Both, the cellular and electrophysiological response to X-ray irradiation were examined. Cellular endpoints such as the induction of micronuclei, apoptosis, number of binucleated cells and expression of connexin43 (Cx 43) were analyzed by standard techniques. For electrophysiological studies a microelectrode array (MEA) was used allowing non-invasive recordings of electrical signals such as signal amplitude and shape, beat rate and conduction velocity. Data analysis was performed using the MATLAB based software DrCell. As a first approach, cardiomyocytes were generated by differentiation of mESC via the formation of embryoid bodies. However, the system proved to be unsuitable due to large intra- and inter-sample variations. In consecutive experiments we used commercially available Cor.At cells, i.e. a pure culture of mESC derived cardiomyocytes. For the analysis of cellular and electrophysiological endpoints Cor.At cells were seeded onto chamber slides or MEA chips, respectively. Irradiation with 0.5 and 2 Gy X-rays (250 kV, 16 mA) was performed two days after seeding. At that time cardiomyocytes are electrically coupled through gap junctions and form a spontaneously beating network. Samples were examined up to four days after exposure. Analysis of the electrophysiological data revealed only minor differences between controls and X-irradiated samples indicating the functionality of cardiomyocytes is not within the dose range examined. Currently, further experiments are performed to statistically verify this finding. Additionally, the expression of Cx 43, a major

  16. Hypothalamic S-nitrosylation contributes to the counter-regulatory response impairment following recurrent hypoglycemia.

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    Xavier Fioramonti

    Full Text Available AIMS: Hypoglycemia is a severe side effect of intensive insulin therapy. Recurrent hypoglycemia (RH impairs the counter-regulatory response (CRR which restores euglycemia. During hypoglycemia, ventromedial hypothalamus (VMH production of nitric oxide (NO and activation of its receptor soluble guanylyl cyclase (sGC are critical for the CRR. Hypoglycemia also increases brain reactive oxygen species (ROS production. NO production in the presence of ROS causes protein S-nitrosylation. S-nitrosylation of sGC impairs its function and induces desensitization to NO. We hypothesized that during hypoglycemia, the interaction between NO and ROS increases VMH sGC S-nitrosylation levels and impairs the CRR to subsequent episodes of hypoglycemia. VMH ROS production and S-nitrosylation were quantified following three consecutive daily episodes of insulin-hypoglycemia (RH model. The CRR was evaluated in rats in response to acute insulin-induced hypoglycemia or via hypoglycemic-hyperinsulinemic clamps. Pretreatment with the anti-oxidant N-acetyl-cysteine (NAC was used to prevent increased VMH S-nitrosylation. RESULTS: Acute insulin-hypoglycemia increased VMH ROS levels by 49±6.3%. RH increased VMH sGC S-nitrosylation. Increasing VMH S-nitrosylation with intracerebroventricular injection of the nitrosylating agent S-nitroso-L-cysteine (CSNO was associated with decreased glucagon secretion during hypoglycemic clamp. Finally, in RH rats pre-treated with NAC (0.5% in drinking water for 9 days hypoglycemia-induced VMH ROS production was prevented and glucagon and epinephrine production was not blunted in response to subsequent insulin-hypoglycemia. CONCLUSION: These data suggest that NAC may be clinically useful in preventing impaired CRR in patients undergoing intensive-insulin therapy.

  17. Genetic screening of new genes responsible for cellular adaptation to hypoxia using a genome-wide shRNA library.

    Science.gov (United States)

    Yoshino, Seiko; Hara, Toshiro; Weng, Jane S; Takahashi, Yuka; Seiki, Motoharu; Sakamoto, Takeharu

    2012-01-01

    Oxygen is a vital requirement for multi-cellular organisms to generate energy and cells have developed multiple compensatory mechanisms to adapt to stressful hypoxic conditions. Such adaptive mechanisms are intricately interconnected with other signaling pathways that regulate cellular functions such as cell growth. However, our understanding of the overall system governing the cellular response to the availability of oxygen remains limited. To identify new genes involved in the response to hypoxic stress, we have performed a genome-wide gene knockdown analysis in human lung carcinoma PC8 cells using an shRNA library carried by a lentiviral vector. The knockdown analysis was performed under both normoxic and hypoxic conditions to identify shRNA sequences enriched or lost in the resulting selected cell populations. Consequently, we identified 56 candidate genes that might contribute to the cellular response to hypoxia. Subsequent individual knockdown of each gene demonstrated that 13 of these have a significant effect upon oxygen-sensitive cell growth. The identification of BCL2L1, which encodes a Bcl-2 family protein that plays a role in cell survival by preventing apoptosis, validates the successful design of our screen. The other selected genes have not previously been directly implicated in the cellular response to hypoxia. Interestingly, hypoxia did not directly enhance the expression of any of the identified genes, suggesting that we have identified a new class of genes that have been missed by conventional gene expression analyses to identify hypoxia response genes. Thus, our genetic screening method using a genome-wide shRNA library and the newly-identified genes represent useful tools to analyze the cellular systems that respond to hypoxic stress.

  18. Cofilin/Twinstar phosphorylation levels increase in response to impaired coenzyme a metabolism.

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    Katarzyna Siudeja

    Full Text Available Coenzyme A (CoA is a pantothenic acid-derived metabolite essential for many fundamental cellular processes including energy, lipid and amino acid metabolism. Pantothenate kinase (PANK, which catalyses the first step in the conversion of pantothenic acid to CoA, has been associated with a rare neurodegenerative disorder PKAN. However, the consequences of impaired PANK activity are poorly understood. Here we use Drosophila and human neuronal cell cultures to show how PANK deficiency leads to abnormalities in F-actin organization. Cells with reduced PANK activity are characterized by abnormally high levels of phosphorylated cofilin, a conserved actin filament severing protein. The increased levels of phospho-cofilin coincide with morphological changes of PANK-deficient Drosophila S2 cells and human neuronal SHSY-5Y cells. The latter exhibit also markedly reduced ability to form neurites in culture--a process that is strongly dependent on actin remodeling. Our results reveal a novel and conserved link between a metabolic biosynthesis pathway, and regulation of cellular actin dynamics.

  19. P2X7 Cell Death Receptor Activation and Mitochondrial Impairment in Oxaliplatin-Induced Apoptosis and Neuronal Injury: Cellular Mechanisms and In Vivo Approach.

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    France Massicot

    Full Text Available Limited information is available regarding the cellular mechanisms of oxaliplatin-induced painful neuropathy during exposure of patients to this drug. We therefore determined oxidative stress in cultured cells and evaluated its occurrence in C57BL/6 mice. Using both cultured neuroblastoma (SH-SY5Y and macrophage (RAW 264.7 cell lines and also brain tissues of oxaliplatin-treated mice, we investigated whether oxaliplatin (OXA induces oxidative stress and apoptosis. Cultured cells were treated with 2-200 µM OXA for 24 h. The effects of pharmacological inhibitors of oxidative stress or inflammation (N-acetyl cysteine, ibuprofen, acetaminophen were also tested. Inhibitors were added 30 min before OXA treatment and then in combination with OXA for 24 h. In SH-SY5Y cells, OXA caused a significant dose-dependent decrease in viability, a large increase in ROS and NO production, lipid peroxidation and mitochondrial impairment as assessed by a drop in mitochondrial membrane potential, which are deleterious for the cell. An increase in levels of negatively charged phospholipids such as cardiolipin but also phosphatidylserine and phosphatidylinositol, was also observed. Additionally, OXA caused concentration-dependent P2X7 receptor activation, increased chromatin condensation and caspase-3 activation associated with TNF-α and IL-6 release. The majority of these toxic effects were equally observed in Raw 264.7 which also presented high levels of PGE2. Pretreatment of SH-SY5Y cells with pharmacological inhibitors significantly reduced or blocked all the neurotoxic OXA effects. In OXA-treated mice (28 mg/kg cumulated dose significant cold hyperalgesia and oxidative stress in the tested brain areas were shown. Our study suggests that targeting P2X7 receptor activation and mitochondrial impairment might be a potential therapeutic strategy against OXA-induced neuropathic pain.

  20. Inhibition of autophagy and glycolysis by nitric oxide during hypoxia-reoxygenation impairs cellular bioenergetics and promotes cell death in primary neurons.

    Science.gov (United States)

    Benavides, Gloria A; Liang, Qiuli; Dodson, Matthew; Darley-Usmar, Victor; Zhang, Jianhua

    2013-12-01

    Excessive nitric oxide (NO) production is known to damage mitochondrial proteins and the autophagy repair pathway and so can potentially contribute to neurotoxicity. Accordingly, we hypothesized that protection against protein damage from reactive oxygen and nitrogen species under conditions of low oxygen by the autophagy pathway in neurons would be impaired by NO and enhance bioenergetic dysfunction. Rat primary cortical neurons had the same basal cellular respiration in hypoxia as in normoxia, whereas NO-exposed cells exhibited a gradual decrease in mitochondrial respiration in hypoxia. Upon reoxygenation, the respiration in NO-treated cells did not recover to prehypoxic levels. Hypoxia-reoxygenation in the presence of NO was associated with inhibition of autophagy, and the inability to recover during reoxygenation was exacerbated by an inhibitor of autophagy, 3-methyladenine. The effects of hypoxia could be recapitulated by inhibiting glycolytic flux under normoxic conditions. Under both normoxic and hypoxic conditions NO exposure induced immediate stimulation of glycolysis, but prolonged NO exposure, associated with irreversible inhibition of mitochondrial respiration in hypoxia, inhibited glycolysis. Importantly, we found that NO inhibited basal respiration under normoxic conditions only when glucose was absent from the medium or glycolysis was inhibited by 2-deoxy-d-glucose, revealing a novel NO-dependent mechanism for the inhibition of mitochondrial respiration that is modulated by glycolysis. Taken together these data suggest an oxygen-dependent interaction between mitochondrial respiration, glycolysis, and autophagy in protecting neuronal cells exposed to NO. Importantly, they indicate that mitochondrial dysfunction is intimately linked to a failure of glycolytic flux induced by exposure to NO. In addition, these studies provide new insights into the understanding of how autophagy and NO may play interactive roles in neuroinflammation-induced cellular

  1. Plasmid DNA Vaccine Co-Immunisation Modulates Cellular and Humoral Immune Responses Induced by Intranasal Inoculation in Mice.

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    Deborah F L King

    Full Text Available An effective HIV vaccine will likely require induction of both mucosal and systemic cellular and humoral immune responses. We investigated whether intramuscular (IM delivery of electroporated plasmid DNA vaccine and simultaneous protein vaccinations by intranasal (IN and IM routes could be combined to induce mucosal and systemic cellular and humoral immune responses to a model HIV-1 CN54 gp140 antigen in mice.Co-immunisation of DNA with intranasal protein successfully elicited both serum and vaginal IgG and IgA responses, whereas DNA and IM protein co-delivery did not induce systemic or mucosal IgA responses. Cellular IFNγ responses were preserved in co-immunisation protocols compared to protein-only vaccination groups. The addition of DNA to IN protein vaccination reduced the strong Th2 bias observed with IN protein vaccination alone. Luminex analysis also revealed that co-immunisation with DNA and IN protein induced expression of cytokines that promote B-cell function, generation of TFH cells and CCR5 ligands that can reduce HIV infectivity.These data suggest that while IN inoculation alone elicits both cellular and humoral responses, co-administration with homologous DNA vaccination can tailor these towards a more balanced Th1/Th2 phenotype modulating the cellular cytokine profile while eliciting high-levels of antigen-specific antibody. This work provides insights on how to generate differential immune responses within the same vaccination visit, and supports co-immunisation with DNA and protein by a mucosal route as a potential delivery strategy for HIV vaccines.

  2. Nitrosative stress, cellular stress response, and thiol homeostasis in patients with Alzheimer's disease.

    Science.gov (United States)

    Calabrese, Vittorio; Sultana, Rukhsana; Scapagnini, Giovanni; Guagliano, Eleonora; Sapienza, Maria; Bella, Rita; Kanski, Jaroslaw; Pennisi, Giovanni; Mancuso, Cesare; Stella, Anna Maria Giuffrida; Butterfield, D A

    2006-01-01

    Alzheimer's disease (AD) is a neurodegenerative disorder with cognitive and memory decline, personality changes, and synapse loss. Increasing evidence indicates that factors such as oxidative and nitrosative stress, glutathione depletion, and impaired protein metabolism can interact in a vicious cycle, which is central to AD pathogenesis. In the present study, we demonstrate that brains of AD patients undergo oxidative changes classically associated with a strong induction of the so-called vitagenes, including the heat shock proteins (HSPs) heme oxygenase-1 (HO-1), HSP60, and HSP72, as well as thioredoxin reductase (TRXr). In inferior parietal brain of AD patients, a significant increase in the expression of HO-1 and TRXr was observed, whereas HO-2 expression was decreased, compared with controls. TRHr was not increased in AD cerebellum. Plasma GSH was decreased in AD patients, compared with the control group, and was associated with a significant increase in oxidative stress markers (i.e., GSSG, hydroxynonenal, protein carbonyl content, and nitrotyrosine). In AD lymphocytes, we observed an increased expression of inducible nitric oxide synthase, HO-1, Hsp72, HSP60, and TRXr. Our data support a role for nitrative stress in the pathogenesis of AD and indicate that the stress-responsive genes, such as HO-1 and TRXr, may represent important targets for novel cytoprotective strategies.

  3. Cellular Response of the Amoeba Acanthamoeba castellanii to Chlorine, Chlorine Dioxide, and Monochloramine Treatments ▿

    Science.gov (United States)

    Mogoa, Emerancienne; Bodet, Charles; Morel, Franck; Rodier, Marie-Hélène; Legube, Bernard; Héchard, Yann

    2011-01-01

    Acanthamoeba castellanii is a free-living amoebae commonly found in water systems. Free-living amoebae might be pathogenic but are also known to bear phagocytosis-resistant bacteria, protecting these bacteria from water treatments. The mode of action of these treatments is poorly understood, particularly on amoebae. It is important to examine the action of these treatments on amoebae in order to improve them. The cellular response to chlorine, chlorine dioxide, and monochloramine was tested on A. castellanii trophozoites. Doses of disinfectants leading to up to a 3-log reduction were compared by flow cytometry and electron microscopy. Chlorine treatment led to size reduction, permeabilization, and retraction of pseudopods. In addition, treatment with chlorine dioxide led to a vacuolization of the cytoplasm. Monochloramine had a dose-dependent effect. At the highest doses monochloramine treatment resulted in almost no changes in cell size and permeability, as shown by flow cytometry, but the cell surface became smooth and dense, as seen by electron microscopy. We show that these disinfectants globally induced size reduction, membrane permeabilization, and morphological modifications but that they have a different mode of action on A. castellanii. PMID:21602398

  4. Restriction of Receptor Movement Alters Cellular Response: Physical Force Sensing by EphA2

    Energy Technology Data Exchange (ETDEWEB)

    Salaita, Khalid; Nair, Pradeep M; Petit, Rebecca S; Neve, Richard M; Das, Debopriya; Gray, Joe W; Groves, Jay T

    2009-09-09

    Activation of the EphA2 receptor tyrosine kinase by ephrin-A1 ligands presented on apposed cell surfaces plays important roles in development and exhibits poorly understood functional alterations in cancer. We reconstituted this intermembrane signaling geometry between live EphA2-expressing human breast cancer cells and supported membranes displaying laterally mobile ephrin-A1. Receptor-ligand binding, clustering, and subsequent lateral transport within this junction were observed. EphA2 transport can be blocked by physical barriers nanofabricated onto the underlying substrate. This physical reorganization of EphA2 alters the cellular response to ephrin-A1, as observed by changes in cytoskeleton morphology and recruitment of a disintegrin and metalloprotease 10. Quantitative analysis of receptor-ligand spatial organization across a library of 26 mammary epithelial cell lines reveals characteristic differences that strongly correlate with invasion potential. These observations reveal a mechanism for spatio-mechanical regulation of EphA2 signaling pathways.

  5. Cellular Stress Response Gene Expression During Upper and Lower Body High Intensity Exercises

    Science.gov (United States)

    Kochanowicz, Andrzej; Sawczyn, Stanisław; Niespodziński, Bartłomiej; Mieszkowski, Jan; Kochanowicz, Kazimierz

    2017-01-01

    Objectives The aim was to compare the effect of upper and lower body high-intensity exercise on chosen genes expression in athletes and non-athletes. Method Fourteen elite male artistic gymnasts (EAG) aged 20.6 ± 3.3 years and 14 physically active men (PAM) aged 19.9 ± 1.0 years performed lower and upper body 30 s Wingate Tests. Blood samples were collected before, 5 and 30 minutes after each effort to assess gene expression via PCR. Results Significantly higher mechanical parameters after lower body exercise was observed in both groups, for relative power (8.7 ± 1.2 W/kg in gymnasts, 7.2 ± 1.2 W/kg in controls, p = 0.01) and mean power (6.7 ± 0.7 W/kg in gymnasts, 5.4 ± 0.8 W/kg in controls, p = 0.01). No differences in lower versus upper body gene expression were detected for all tested genes as well as between gymnasts and physical active man. For IL-6 m-RNA time-dependent effect was observed. Conclusions Because of no significant differences in expression of genes associated with cellular stress response the similar adaptive effect to exercise may be obtained so by lower and upper body exercise. PMID:28141870

  6. Cellular response of the amoeba Acanthamoeba castellanii to chlorine, chlorine dioxide, and monochloramine treatments.

    Science.gov (United States)

    Mogoa, Emerancienne; Bodet, Charles; Morel, Franck; Rodier, Marie-Hélène; Legube, Bernard; Héchard, Yann

    2011-07-01

    Acanthamoeba castellanii is a free-living amoebae commonly found in water systems. Free-living amoebae might be pathogenic but are also known to bear phagocytosis-resistant bacteria, protecting these bacteria from water treatments. The mode of action of these treatments is poorly understood, particularly on amoebae. It is important to examine the action of these treatments on amoebae in order to improve them. The cellular response to chlorine, chlorine dioxide, and monochloramine was tested on A. castellanii trophozoites. Doses of disinfectants leading to up to a 3-log reduction were compared by flow cytometry and electron microscopy. Chlorine treatment led to size reduction, permeabilization, and retraction of pseudopods. In addition, treatment with chlorine dioxide led to a vacuolization of the cytoplasm. Monochloramine had a dose-dependent effect. At the highest doses monochloramine treatment resulted in almost no changes in cell size and permeability, as shown by flow cytometry, but the cell surface became smooth and dense, as seen by electron microscopy. We show that these disinfectants globally induced size reduction, membrane permeabilization, and morphological modifications but that they have a different mode of action on A. castellanii.

  7. Bacterial formyl peptides affect the innate cellular antimicrobial responses of larval Galleria mellonella (Insecta: Lepidoptera).

    Science.gov (United States)

    Alavo, Thiery B C; Dunphy, Gary B

    2004-04-01

    The non-self cellular (hemocytic) responses of Galleria mellonella larvae, including the attachment to slides and the removal of the bacteria Xenorhabdus nematophila and Bacillus subtilis from the hemolymph, were affected by N-formyl peptides. Both N-formyl methionyl-leucyl-phenylalanine (fMLF) and the ester derivative decreased hemocyte adhesion in vitro, and both elevated hemocyte counts and suppressed the removal of both X. nematophila and B. subtilis from the hemolymph in vivo. The amide derivative and the antagonist tertiary-butoxy-carbonyl-methionyl-leucyl-phenylalanine (tBOC) increased hemocyte attachment to glass. The fMLF suppressed protein discharge from monolayers of granular cells with and without bacterial stimulation, while tBOC stimulated protein discharge. The peptide tBOC offset the effects of fMLF in vitro and in vivo. This is the first report implying the existence of formyl peptide receptors on insect hemocytes in which the compounds fMLF and tBOC inhibited and activated hemocyte activity, respectively.

  8. Metabolomic profiling of cellular responses to carvedilol enantiomers in vascular smooth muscle cells.

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    Mingxuan Wang

    Full Text Available Carvedilol is a non-selective β-blocker indicated in the treatment of hypertension and heart failure. Although the differential pharmacological effects of individual Carvedilol enantiomer is supported by preceding studies, the cellular response to each enantiomer is not well understood. Here we report the use of GC-MS metabolomic profiling to study the effects of Carvedilol enantiomers on vascular smooth muscle cells (A7r5 and to shed new light on molecular events underlying Carvedilol treatment. The metabolic analysis revealed alternations in the levels of 8 intracellular metabolites and 5 secreted metabolites in A7r5 cells incubated separately with S- and R-Carvedilol. Principal component analysis of the metabolite data demonstrated the characteristic metabolic signatures in S- and R-Carvedilol-treated cells. A panel of metabolites, including L-serine, L-threonine, 5-oxoproline, myristic acid, palmitic acid and inositol are closely correlated to the vascular smooth muscle contraction. Our findings reveal the differentiating metabolites for A7r5 cells incubated with individual enantiomer of Carvedilol, which opens new perspectives to employ metabolic profiling platform to study chiral drug-cell interactions and aid their incorporation into future improvement of β-blocker therapy.

  9. Temporal regulation of cerebellar EGL migration through a switch in cellular responsiveness to the meninges.

    Science.gov (United States)

    Zhu, Yan; Yu, Tao; Rao, Yi

    2004-03-01

    We have studied the temporal and spatial control of cell migration from the external germinal layer (EGL) in the mammalian cerebellum as a model for cortical migration. Our results have demonstrated that embryonic EGL cells do not migrate into internal layers because they respond to a diffusible attractant in the meninges, the nonneural tissues covering the nervous system, and to a repellent in the neuroepithelium. Two developmental changes are important for postnatal EGL migration: the disappearance of the repellent in the inner layers and a switch in cellular responsiveness of EGL cells so that the postnatal EGL cells respond to the repellent, but not the attractant in the meninges. Besides revealing the signaling role of meninges in cortical development, our study suggests that an active mechanism is required to prevent cell migration, and that mechanisms of cell migration should be studied even in the absence of apparent changes in cell positions. We propose a model for the developmental control of neuronal migration in the cerebellar cortex.

  10. Evidence for a regulatory role of diatom silicon transporters in cellular silicon responses.

    Science.gov (United States)

    Shrestha, Roshan P; Hildebrand, Mark

    2015-01-01

    The utilization of silicon by diatoms has both global and small-scale implications, from oceanic primary productivity to nanotechnological applications of their silica cell walls. The sensing and transport of silicic acid are key aspects of understanding diatom silicon utilization. At low silicic acid concentrations (silicon starvation. SIT1 and SIT2 were localized in the plasma membrane, and protein levels were generally inversely correlated with cellular silicon needs, with a distinct response being found when the two SITs were compared. We developed highly effective approaches for RNA interference and antisense knockdowns, the first such approaches developed for a centric diatom. SIT knockdown differentially affected the uptake of silicon and the incorporation of silicic acid and resulted in the induction of lipid accumulation under silicon starvation conditions far earlier than in the wild-type cells, suggesting that the cells were artificially sensing silicon limitation. The data suggest that the transport role of the SITs is relatively minor under conditions with sufficient silicic acid. Their primary role is to sense silicic acid levels to evaluate whether the cell can proceed with its cell wall formation and division processes.

  11. Beneficial effects of low dose radiation in response to the oncogenic KRAS induced cellular transformation.

    Science.gov (United States)

    Kim, Rae-Kwon; Kim, Min-Jung; Seong, Ki Moon; Kaushik, Neha; Suh, Yongjoon; Yoo, Ki-Chun; Cui, Yan-Hong; Jin, Young Woo; Nam, Seon Young; Lee, Su-Jae

    2015-10-30

    Recently low dose irradiation has gained attention in the field of radiotherapy. For lack of understanding of the molecular consequences of low dose irradiation, there is much doubt concerning its risks on human beings. In this article, we report that low dose irradiation is capable of blocking the oncogenic KRAS-induced malignant transformation. To address this hypothesis, we showed that low dose irradiation, at doses of 0.1 Gray (Gy); predominantly provide defensive response against oncogenic KRAS -induced malignant transformation in human cells through the induction of antioxidants without causing cell death and acts as a critical regulator for the attenuation of reactive oxygen species (ROS). Importantly, we elucidated that knockdown of antioxidants significantly enhanced ROS generation, invasive and migratory properties and abnormal acini formation in KRAS transformed normal as well as cancer cells. Taken together, this study demonstrates that low dose irradiation reduces the KRAS induced malignant cellular transformation through diminution of ROS. This interesting phenomenon illuminates the beneficial effects of low dose irradiation, suggesting one of contributory mechanisms for reducing the oncogene induced carcinogenesis that intensify the potential use of low dose irradiation as a standard regimen.

  12. CELLULAR RESPONSES TO DNA DAMAGE AND ONCOGENESIS BY THE p53 AND pRb/E2F PATHWAYS

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    Elza Ibrahim Auerkari

    2015-07-01

    Full Text Available Cellular responses to stress including DNA damage, show multiple options involving the mechanisms of growth arrest. DNA repair and programmed cell death or apoptosis. Failures in these mechanisms can result in oncogenesis or accelerated senescence. Much of the response is coordinated by p53, a nuclear phosphoprotein with a central role in the defences against physical, chemical and pathogenic agents which challenge the DNA integrity. The p53 pathways for mobilising the cellular defences are linked to the pRB/E2D pathways regulating the cell cycle progression. This paper aims to review the current understanding on the networks and main molecular machinery of these processes. In addition, the implications on cellular decision making for the defences as well as revolutionary aspects of these mechanisms are discussed in brief.

  13. Incorporation of a dietary omega 3 fatty acid impairs murine macrophage responses to Mycobacterium tuberculosis.

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    Diana L Bonilla

    Full Text Available BACKGROUND: Beside their health benefits, dietary omega 3 polyunsaturated fatty acids (n-3 PUFA might impair host resistance to Mycobacterium tuberculosis (Mtb by creating an immunosuppressive environment. We hypothesized that incorporation of n-3 PUFA suppresses activation of macrophage antimycobacterial responses and favors bacterial growth, in part, by modulating the IFNgamma-mediated signaling pathway. METHODOLOGY/PRINCIPAL FINDINGS: Murine macrophage-like J774A.1 cells were incubated with bovine serum albumin (BSA-conjugated docosahexaenoic acid (DHA; 22:6n-3 or BSA alone, activated with recombinant IFNgamma, and infected with a virulent strain (H37Rv of M. tuberculosis. The fatty acid composition of macrophage membranes was modified significantly by DHA treatment. DHA-treated macrophages were less effective in controlling intracellular mycobacteria and showed impaired oxidative metabolism and reduced phagolysosome maturation. Incorporation of DHA resulted in defective macrophage activation, as characterized by reduced production of pro-inflammatory cytokines (TNFalpha, IL-6 and MCP-1, and lower expression of co-stimulatory molecules (CD40 and CD86. DHA treatment impaired STAT1 phosphorylation and colocalization of the IFNgamma receptor with lipid rafts, without affecting surface expression of IFNgamma receptor. CONCLUSIONS/SIGNIFICANCE: We conclude that DHA reduces the ability of J774A.1 cells to control M. tuberculosis in response to activation by IFNgamma, by modulation of IFNgamma receptor signaling and function, suggesting that n-3 PUFA-enriched diets may have a detrimental effect on host immunity to tuberculosis.

  14. A new in vitro model to study cellular responses after thermomechanical damage in monolayer cultures.

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    Alice Hettler

    Full Text Available Although electrosurgical instruments are widely used in surgery to cut tissue layers or to achieve hemostasis by coagulation (electrocautery, only little information is available concerning the inflammatory or immune response towards the debris generated. Given the elevated local temperatures required for successful electrocautery, the remaining debris is likely to contain a plethora of compounds entirely novel to the intracorporal setting. A very common in vitro method to study cell migration after mechanical damage is the scratch assay, however, there is no established model for thermomechanical damage to characterise cellular reactions. In this study, we established a new in vitro model to investigate exposure to high temperature in a carefully controlled cell culture system. Heatable thermostat-controlled aluminium stamps were developed to induce local damage in primary human umbilical vein endothelial cells (HUVEC. The thermomechanical damage invoked is reproducibly locally confined, therefore allowing studies, under the same experimental conditions, of cells affected to various degrees as well as of unaffected cells. We show that the unaffected cells surrounding the thermomechanical damage zone are able to migrate into the damaged area, resulting in a complete closure of the 'wound' within 48 h. Initial studies have shown that there are significant morphological and biological differences in endothelial cells after thermomechanical damage compared to the mechanical damage inflicted by using the unheated stamp as a control. Accordingly, after thermomechanical damage, cell death as well as cell protection programs were activated. Mononuclear cells adhered in the area adjacent to thermomechanical damage, but not to the zone of mechanical damage. Therefore, our model can help to understand the differences in wound healing during the early phase of regeneration after thermomechanical vs. mechanical damage. Furthermore, this model lends itself

  15. Effect of MWCNT surface and chemical modification on in vitro cellular response

    Science.gov (United States)

    Fraczek-Szczypta, Aneta; Menaszek, Elzbieta; Syeda, Tahmina Bahar; Misra, Anil; Alavijeh, Mohammad; Adu, Jimi; Blazewicz, Stanislaw

    2012-10-01

    The aim of this study was to evaluate the impact of multi-walled carbon nanotubes (MWCNTs with diameter in the range of 10-30 nm) before and after chemical surface functionalisation on macrophages response. The study has shown that the detailed analysis of the physicochemical properties of this particular form of carbon nanomaterial is a crucial issue to interpret properly its impact on the cellular response. Effects of carbon nanotubes (CNTs) characteristics, including purity, dispersity, chemistry and dimension upon the nature of the cell environment-material interaction were investigated. Various techniques involving electron microscopy (SEM, TEM), infrared spectroscopy (FTIR), inductively coupled plasma optical emission spectrometry, X-ray photoelectron spectroscopy have been employed to evaluate the physicochemical properties of the materials. The results demonstrate that the way of CNT preparation prior to biological tests has a fundamental impact on their behavior, cell viability and the nature of cell-nanotube interaction. Chemical functionalisation of CNTs in an acidic ambient (MWCNT-Fs) facilitates interaction with cells by two possible mechanisms, namely, endocytosis/phagocytosis and by energy-independent passive process. The results indicate that MWCNT-F in macrophages may decrease the cell proliferation process by interfering with the mitotic apparatus without negative consequences on cell viability. On the contrary, the as-prepared MWCNTs, without any surface treatment produce the least reduction in cell proliferation with reference to control, and the viability of cells exposed to this sample was substantially reduced with respect to control. A possible explanation of such a phenomenon is the presence of MWCNT's agglomerates surrounded by numerous cells releasing toxic substances.

  16. Effect of MWCNT surface and chemical modification on in vitro cellular response

    Energy Technology Data Exchange (ETDEWEB)

    Fraczek-Szczypta, Aneta; Menaszek, Elzbieta [AGH-University of Science and Technology, Department of Biomaterials, Faculty of Materials Science and Ceramics (Poland); Syeda, Tahmina Bahar; Misra, Anil; Alavijeh, Mohammad [Pharmidex Pharmaceutical Services (United Kingdom); Adu, Jimi [University of Brighton, School of Pharmacy and Biomolecular Sciences (United Kingdom); Blazewicz, Stanislaw, E-mail: blazew@agh.edu.pl [AGH-University of Science and Technology, Department of Biomaterials, Faculty of Materials Science and Ceramics (Poland)

    2012-10-15

    The aim of this study was to evaluate the impact of multi-walled carbon nanotubes (MWCNTs with diameter in the range of 10-30 nm) before and after chemical surface functionalisation on macrophages response. The study has shown that the detailed analysis of the physicochemical properties of this particular form of carbon nanomaterial is a crucial issue to interpret properly its impact on the cellular response. Effects of carbon nanotubes (CNTs) characteristics, including purity, dispersity, chemistry and dimension upon the nature of the cell environment-material interaction were investigated. Various techniques involving electron microscopy (SEM, TEM), infrared spectroscopy (FTIR), inductively coupled plasma optical emission spectrometry, X-ray photoelectron spectroscopy have been employed to evaluate the physicochemical properties of the materials. The results demonstrate that the way of CNT preparation prior to biological tests has a fundamental impact on their behavior, cell viability and the nature of cell-nanotube interaction. Chemical functionalisation of CNTs in an acidic ambient (MWCNT-Fs) facilitates interaction with cells by two possible mechanisms, namely, endocytosis/phagocytosis and by energy-independent passive process. The results indicate that MWCNT-F in macrophages may decrease the cell proliferation process by interfering with the mitotic apparatus without negative consequences on cell viability. On the contrary, the as-prepared MWCNTs, without any surface treatment produce the least reduction in cell proliferation with reference to control, and the viability of cells exposed to this sample was substantially reduced with respect to control. A possible explanation of such a phenomenon is the presence of MWCNT's agglomerates surrounded by numerous cells releasing toxic substances.

  17. Persistent effects of chronic clozapine on the cellular and behavioral responses to LSD in mice.

    Science.gov (United States)

    Moreno, José L; Holloway, Terrell; Umali, Adrienne; Rayannavar, Vinayak; Sealfon, Stuart C; González-Maeso, Javier

    2013-01-01

    In schizophrenia patients, optimal treatment with antipsychotics requires weeks to months of sustained drug therapy. However, single administration of antipsychotic drugs can reverse schizophrenia-like behavioral alterations in rodent models of psychosis. This raises questions about the physiological relevance of such antipsychotic-like activity. This study evaluates the effects of chronic treatment with clozapine on the cellular and behavioral responses induced by the hallucinogenic serotonin 5-HT(2A) receptor agonist lysergic acid diethylamide (LSD) as a mouse model of psychosis. Mice were treated chronically (21 days) with 25 mg/kg/day clozapine. Experiments were conducted 1, 7, 14, and 21 days after the last clozapine administration. [(3)H]Ketanserin binding and 5-HT ( 2A ) mRNA expression were determined in mouse somatosensory cortex. Head-twitch behavior, expression of c-fos, which is induced by all 5-HT(2A) agonists, and expression of egr-1 and egr-2, which are LSD-like specific, were assayed. Head-twitch response was decreased and [(3)H]ketanserin binding was downregulated in 1, 7, and 14 days after chronic clozapine. 5-HT ( 2A ) mRNA was reduced 1 day after chronic clozapine. Induction of c-fos, but not egr-1 and egr-2, was rescued 7 days after chronic clozapine. These effects were not observed after short treatment (2 days) with clozapine or chronic haloperidol (1 mg/kg/day). Our findings provide a murine model of chronic atypical antipsychotic drug action and suggest downregulation of the 5-HT(2A) receptor as a potential mechanism involved in these persistent therapeutic-like effects.

  18. Coordination between p21 and DDB2 in the cellular response to UV radiation.

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    Hao Li

    Full Text Available The tumor suppressor p53 guides the cellular response to DNA damage mainly by regulating expression of target genes. The cyclin-dependent kinase inhibitor p21, which is induced by p53, can both arrest the cell cycle and inhibit apoptosis. Interestingly, p53-inducible DDB2 (damaged-DNA binding protein 2 promotes apoptosis by mediating p21 degradation after ultraviolet (UV-induced DNA damage. Here, we developed an integrated model of the p53 network to explore how the UV-irradiated cell makes a decision between survival and death and how the activities of p21 and DDB2 are modulated. By numerical simulations, we found that p53 is activated progressively and the promoter selectivity of p53 depends on its concentration. For minor DNA damage, p53 settles at an intermediate level. p21 is induced by p53 to arrest the cell cycle via inhibiting E2F1 activity, allowing for DNA repair. The proapoptotic genes are expressed at low levels. For severe DNA damage, p53 undergoes a two-phase behavior and accumulates to high levels in the second phase. Consequently, those proapoptotic proteins accumulate remarkably. Bax activates the release of cytochrome c, while DDB2 promotes the degradation of p21, which leads to activation of E2F1 and induction of Apaf-1. Finally, the caspase cascade is activated to trigger apoptosis. We revealed that the downregulation of p21 is necessary for apoptosis induction and PTEN promotes apoptosis by amplifying p53 activation. This work demonstrates that how the dynamics of the p53 network can be finely regulated through feed-forward and feedback loops within the network and emphasizes the importance of p21 regulation in the DNA damage response.

  19. Heat-shock-induced cellular responses to temperature elevations occurring during orthopaedic cutting.

    Science.gov (United States)

    Dolan, E B; Haugh, M G; Tallon, D; Casey, C; McNamara, L M

    2012-12-07

    Severe heat-shock to bone cells caused during orthopaedic procedures can result in thermal damage, leading to cell death and initiating bone resorption. By contrast, mild heat-shock has been proposed to induce bone regeneration. In this study, bone cells are exposed to heat-shock for short durations occurring during surgical cutting. Cellular viability, necrosis and apoptosis are investigated immediately after heat-shock and following recovery of 12, 24 h and 4 days, in osteocyte-like MLO-Y4 and osteoblast-like MC3T3-E1 cells, using flow cytometry. The regeneration capacity of heat-shocked Balb/c mesenchymal stem cells (MSCs) and MC3T3-E1s has been investigated following 7 and 14 day's recovery, by quantifying proliferation, differentiation and mineralization. An immediate necrotic response to heat-shock was shown in cells exposed to elevated temperatures (45°C, 47°C and most severe at 60°C). A longer-term apoptotic response is induced in MLO-Y4s and, to a lesser extent, in MC3T3-E1s. Heat-shock-induced differentiation and mineralization by MSCs. These findings indicate that heat-shock is more likely to induce apoptosis in osteocytes than osteoblasts, which might reflect their role as sensors detecting and communicating damage within bone. Furthermore, it is shown for the first time that mild heat-shock (less than equal to 47°C) for durations occurring during surgical cutting can positively enhance osseointegration by osteoprogenitors.

  20. Knowledge-based matrix factorization temporally resolves the cellular responses to IL-6 stimulation

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    Gretz Norbert

    2010-11-01

    Full Text Available Abstract Background External stimulations of cells by hormones, cytokines or growth factors activate signal transduction pathways that subsequently induce a re-arrangement of cellular gene expression. The analysis of such changes is complicated, as they consist of multi-layered temporal responses. While classical analyses based on clustering or gene set enrichment only partly reveal this information, matrix factorization techniques are well suited for a detailed temporal analysis. In signal processing, factorization techniques incorporating data properties like spatial and temporal correlation structure have shown to be robust and computationally efficient. However, such correlation-based methods have so far not be applied in bioinformatics, because large scale biological data rarely imply a natural order that allows the definition of a delayed correlation function. Results We therefore develop the concept of graph-decorrelation. We encode prior knowledge like transcriptional regulation, protein interactions or metabolic pathways in a weighted directed graph. By linking features along this underlying graph, we introduce a partial ordering of the features (e.g. genes and are thus able to define a graph-delayed correlation function. Using this framework as constraint to the matrix factorization task allows us to set up the fast and robust graph-decorrelation algorithm (GraDe. To analyze alterations in the gene response in IL-6 stimulated primary mouse hepatocytes, we performed a time-course microarray experiment and applied GraDe. In contrast to standard techniques, the extracted time-resolved gene expression profiles showed that IL-6 activates genes involved in cell cycle progression and cell division. Genes linked to metabolic and apoptotic processes are down-regulated indicating that IL-6 mediated priming renders hepatocytes more responsive towards cell proliferation and reduces expenditures for the energy metabolism. Conclusions GraDe provides

  1. Neuronal cellular responses to extremely low frequency electromagnetic field exposure: implications regarding oxidative stress and neurodegeneration.

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    Marcella Reale

    Full Text Available Neurodegenerative diseases comprise both hereditary and sporadic conditions characterized by an identifying progressive nervous system dysfunction and distinctive neuopathophysiology. The majority are of non-familial etiology and hence environmental factors and lifestyle play key roles in their pathogenesis. The extensive use of and ever increasing worldwide demand for electricity has stimulated societal and scientific interest on the environmental exposure to low frequency electromagnetic fields (EMFs on human health. Epidemiological studies suggest a positive association between 50/60-Hz power transmission fields and leukemia or lymphoma development. Consequent to the association between EMFs and induction of oxidative stress, concerns relating to development of neurodegenerative diseases, such as Alzheimer disease (AD, have been voiced as the brain consumes the greatest fraction of oxygen and is particularly vulnerable to oxidative stress. Exposure to extremely low frequency (ELF-EMFs are reported to alter animal behavior and modulate biological variables, including gene expression, regulation of cell survival, promotion of cellular differentiation, and changes in cerebral blood flow in aged AD transgenic mice. Alterations in inflammatory responses have also been reported, but how these actions impact human health remains unknown. We hence evaluated the effects of an electromagnetic wave (magnetic field intensity 1 mT; frequency, 50-Hz on a well-characterized immortalized neuronal cell model, human SH-SY5Y cells. ELF-EMF exposure elevated the expession of NOS and O2(-, which were countered by compensatory changes in antioxidant catylase (CAT activity and enzymatic kinetic parameters related to CYP-450 and CAT activity. Actions of ELF-EMFs on cytokine gene expression were additionally evaluated and found rapidly modified. Confronted with co-exposure to H2O2-induced oxidative stress, ELF-EMF proved not as well counteracted and resulted in a

  2. Graphene oxide scaffold accelerates cellular proliferative response and alveolar bone healing of tooth extraction socket

    Directory of Open Access Journals (Sweden)

    Nishida E

    2016-05-01

    Full Text Available Erika Nishida,1 Hirofumi Miyaji,1 Akihito Kato,1 Hiroko Takita,2 Toshihiko Iwanaga,3 Takehito Momose,1 Kosuke Ogawa,1 Shusuke Murakami,1 Tsutomu Sugaya,1 Masamitsu Kawanami11Department of Periodontology and Endodontology, Hokkaido University Graduate School of Dental Medicine, Sapporo, Japan; 2Support Section for Education and Research, Hokkaido University Graduate School of Dental Medicine, Sapporo, Japan; 3Laboratory of Histology and Cytology, Hokkaido University Graduate School of Medicine, Sapporo, JapanAbstract: Graphene oxide (GO consisting of a carbon monolayer has been widely investigated for tissue engineering platforms because of its unique properties. For this study, we fabricated a GO-applied scaffold and assessed the cellular and tissue behaviors in the scaffold. A preclinical test was conducted to ascertain whether the GO scaffold promoted bone induction in dog tooth extraction sockets. For this study, GO scaffolds were prepared by coating the surface of a collagen sponge scaffold with 0.1 and 1 µg/mL GO dispersion. Scaffolds were characterized using scanning electron microscopy (SEM, physical testing, cell seeding, and rat subcutaneous implant testing. Then a GO scaffold was implanted into a dog tooth extraction socket. Histological observations were made at 2 weeks postsurgery. SEM observations show that GO attached to the surface of collagen scaffold struts. The GO scaffold exhibited an interconnected structure resembling that of control subjects. GO application improved the physical strength, enzyme resistance, and adsorption of calcium and proteins. Cytocompatibility tests showed that GO application significantly increased osteoblastic MC3T3-E1 cell proliferation. In addition, an assessment of rat subcutaneous tissue response revealed that implantation of 1 µg/mL GO scaffold stimulated cellular ingrowth behavior, suggesting that the GO scaffold exhibited good biocompatibility. The tissue ingrowth area and DNA contents of 1

  3. Electrical brain responses in language-impaired children reveal grammar-specific deficits.

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    Elisabeth Fonteneau

    Full Text Available BACKGROUND: Scientific and public fascination with human language have included intensive scrutiny of language disorders as a new window onto the biological foundations of language and its evolutionary origins. Specific language impairment (SLI, which affects over 7% of children, is one such disorder. SLI has received robust scientific attention, in part because of its recent linkage to a specific gene and loci on chromosomes and in part because of the prevailing question regarding the scope of its language impairment: Does the disorder impact the general ability to segment and process language or a specific ability to compute grammar? Here we provide novel electrophysiological data showing a domain-specific deficit within the grammar of language that has been hitherto undetectable through behavioural data alone. METHODS AND FINDINGS: We presented participants with Grammatical(G-SLI, age-matched controls, and younger child and adult controls, with questions containing syntactic violations and sentences containing semantic violations. Electrophysiological brain responses revealed a selective impairment to only neural circuitry that is specific to grammatical processing in G-SLI. Furthermore, the participants with G-SLI appeared to be partially compensating for their syntactic deficit by using neural circuitry associated with semantic processing and all non-grammar-specific and low-level auditory neural responses were normal. CONCLUSIONS: The findings indicate that grammatical neural circuitry underlying language is a developmentally unique system in the functional architecture of the brain, and this complex higher cognitive system can be selectively impaired. The findings advance fundamental understanding about how cognitive systems develop and all human language is represented and processed in the brain.

  4. The jejunal cellular responses in chickens infected with a single dose of Ascaridia galli eggs

    DEFF Research Database (Denmark)

    Luna Olivares, Luz Adilia; Kyvsgaard, Niels Christian; Ferdushy, Tania

    2015-01-01

    This histopathological study was carried out in order to investigate the cellular response in the jejunum to Ascaridia galli during the first 7 weeks of infection. Fourty-two ISA Brown chickens (7 weeks old) were infected orally with 500 embryonated A. galli eggs each while 28 chickens were left ...

  5. Cellular and humoral immune responses in a population from the Baringo District, Kenya to Leishmania promastigote lipophosphoglycan

    DEFF Research Database (Denmark)

    Kurtzhals, J A; Hey, A S; Theander, T G

    1992-01-01

    In a cross-sectional house-to-house study in a leishmaniasis-endemic area in Kenya, the cellular and humoral immune response to Leishmania lipophosphoglycan (LPG) was determined. Clinical data, peripheral blood mononuclear cells, and plasma were obtained from 50 individuals over the age of eight...

  6. Comparative analysis of SIV-specific cellular immune responses induced by different vaccine platforms in rhesus macaques.

    Science.gov (United States)

    Valentin, Antonio; McKinnon, Katherine; Li, Jinyao; Rosati, Margherita; Kulkarni, Viraj; Pilkington, Guy R; Bear, Jenifer; Alicea, Candido; Vargas-Inchaustegui, Diego A; Jean Patterson, L; Pegu, Poonam; Liyanage, Namal P M; Gordon, Shari N; Vaccari, Monica; Wang, Yichuan; Hogg, Alison E; Frey, Blake; Sui, Yongjun; Reed, Steven G; Sardesai, Niranjan Y; Berzofsky, Jay A; Franchini, Genoveffa; Robert-Guroff, Marjorie; Felber, Barbara K; Pavlakis, George N

    2014-11-01

    To identify the most promising vaccine candidates for combinatorial strategies, we compared five SIV vaccine platforms including recombinant canary pox virus ALVAC, replication-competent adenovirus type 5 host range mutant RepAd, DNA, modified vaccinia Ankara (MVA), peptides and protein in distinct combinations. Three regimens used viral vectors (prime or boost) and two regimens used plasmid DNA. Analysis at necropsy showed that the DNA-based vaccine regimens elicited significantly higher cellular responses against Gag and Env than any of the other vaccine platforms. The T cell responses induced by most vaccine regimens disseminated systemically into secondary lymphoid tissues (lymph nodes, spleen) and effector anatomical sites (including liver, vaginal tissue), indicative of their role in viral containment at the portal of entry. The cellular and reported humoral immune response data suggest that combination of DNA and viral vectors elicits a balanced immunity with strong and durable responses able to disseminate into relevant mucosal sites.

  7. Effects of different transferrin forms on transferrin receptor expression, iron uptake, and cellular proliferation of human leukemic HL60 cells. Mechanisms responsible for the specific cytotoxicity of transferrin-gallium

    Energy Technology Data Exchange (ETDEWEB)

    Chitambar, C.R.; Seligman, P.A.

    1986-12-01

    We have previously shown that human leukemic cells proliferate normally in serum-free media containing various transferrin forms, but the addition of transferrin-gallium leads to inhibition of cellular proliferation. Because gallium has therapeutic potential, the effects of transferrin-gallium on leukemic cell proliferation, transferrin receptor expression, and cellular iron utilization were studied. The cytotoxicity of gallium is considerably enhanced by its binding to transferrin and cytotoxicity can be reversed by transferrin-iron but not by other transferrin forms. Exposure to transferrin-gallium leads to a marked increase in cell surface transferrin binding sites, but despite this, cellular /sup 59/Fe incorporation is inappropriately low. Although shunting of transferrin-gallium to another cellular compartment has not been ruled out, other studies suggest that transferrin-gallium impairs intracellular release of /sup 59/Fe from transferrin by interfering with processes responsible for intracellular acidification. These studies, taken together, demonstrate that inhibition of cellular iron incorporation by transferrin-gallium is a prerequisite for inhibition of cellular proliferation.

  8. Silencing of ribosomal protein S9 elicits a multitude of cellular responses inhibiting the growth of cancer cells subsequent to p53 activation.

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    Mikael S Lindström

    Full Text Available BACKGROUND: Disruption of the nucleolus often leads to activation of the p53 tumor suppressor pathway through inhibition of MDM2 that is mediated by a limited set of ribosomal proteins including RPL11 and RPL5. The effects of ribosomal protein loss in cultured mammalian cells have not been thoroughly investigated. Here we characterize the cellular stress response caused by depletion of ribosomal protein S9 (RPS9. METHODOLOGY/PRINCIPAL FINDINGS: Depletion of RPS9 impaired production of 18S ribosomal RNA and induced p53 activity. It promoted p53-dependent morphological differentiation of U343MGa Cl2:6 glioma cells as evidenced by intensified expression of glial fibrillary acidic protein and profound changes in cell shape. U2OS osteosarcoma cells displayed a limited senescence response with increased expression of DNA damage response markers, whereas HeLa cervical carcinoma cells underwent cell death by apoptosis. Knockdown of RPL11 impaired p53-dependent phenotypes in the different RPS9 depleted cell cultures. Importantly, knockdown of RPS9 or RPL11 also markedly inhibited cell proliferation through p53-independent mechanisms. RPL11 binding to MDM2 was retained despite decreased levels of RPL11 protein following nucleolar stress. In these settings, RPL11 was critical for maintaining p53 protein stability but was not strictly required for p53 protein synthesis. CONCLUSIONS: p53 plays an important role in the initial restriction of cell proliferation that occurs in response to decreased level of RPS9. Our results do not exclude the possibility that other nucleolar stress sensing molecules act upstream or in parallel to RPL11 to activate p53. Inhibiting the expression of certain ribosomal proteins, such as RPS9, could be one efficient way to reinitiate differentiation processes or to induce senescence or apoptosis in rapidly proliferating tumor cells.

  9. Transcriptome and Proteome Dynamics of the Cellular Response of Shewanella oneidensis to Chromium Stress

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, D.K.

    2005-04-18

    The overall goal of this DOE NABIR project is to characterize the molecular basis and regulation of hexavalent chromium [Cr(VI)] stress response and reduction by Shewanella oneidensis strain MR-1. Temporal genomic profiling and mass spectrometry-based proteomic analysis were employed to characterize the dynamic molecular response of S. oneidensis MR-1 to both acute and chronic Cr(VI) exposure. The acute stress response of aerobic, mid-exponential phase cells shocked to a final concentration of 1 mM potassium chromate (K2CrO4) was examined at post-exposure time intervals of 5, 30, 60, and 90 min relative to untreated cells. The transcriptome of mid-exponential cultures was also analyzed 30 min after shock doses of 0.3, 0.5, or 1 mM K{sub 2}CrO{sub 4}. The tonB1-exbB1-exbD1 genes comprising the TonB1 iron transport system were some of the most highly induced coding sequences (CDSs) after 90 min (up to {approx}240 fold), followed by other genes involved in heme transport, sulfate transport, and sulfur assimilation pathways. In addition, transcript levels for CDSs with annotated functions in DNA repair (dinP, recX, recA, recN) and detoxification processes (so3585, so3586) were substantially increased in Cr(VI)-exposed cells compared to untreated cells. By contrast, genes predicted to encode hydrogenases (HydA, HydB), oxidoreductases (SO0902-03-04, SO1911), iron-sulfur cluster binding proteins (SO4404), decaheme cytochrome c proteins (MtrA, OmcA, OmcB), and a number of LysR or TetR family transcriptional regulators were some of the most highly repressed CDSs following the 90-min shock period. Transcriptome profiles generated from MR-1 cells adapted to 0.3 mM Cr(VI) differed significantly from those characterizing cells exposed to acute Cr(VI) stress without adaptation. Parallel proteomic characterization of soluble protein and membrane protein fractions extracted from Cr(VI)-shocked and Cr(VI)-adapted MR-1 cells was performed using multidimensional HPLC-ESI-MS/MS (both

  10. Negative Regulation of IRF7 Activation by ATF4 Suggests a Cross Regulation Between the Interferon Responses and the Cellular Integrated Stress Responses

    OpenAIRE

    Liang, Qiming; Deng, Hongying; Sun, Chiao-Wang; Tim M. Townes; Zhu, Fanxiu

    2010-01-01

    Cells react to viral infection by exhibiting interferon (IFN)-based innate immune responses and integrated stress responses, but little is known about the interrelationships between the two. We here report a linkage between these two host protective cellular mechanisms. We found that IRF7, the master regulator of type I IFN gene expression, interacts with ATF4, a key component of the integrated stress responses whose translation is induced by viral infection and various stresses. We have demo...

  11. Comparison of Cellular Uptake and Inflammatory Response via Toll-Like Receptor 4 to Lipopolysaccharide and Titanium Dioxide Nanoparticles

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    Akiyoshi Taniguchi

    2013-06-01

    Full Text Available The innate immune response is the earliest cellular response to infectious agents and mediates the interactions between microbes and cells. Toll-like receptors (TLRs play an important role in these interactions. We have already shown that TLRs are involved with the uptake of titanium dioxide nanoparticles (TiO2 NPs and promote inflammatory responses. In this paper, we compared role of cellular uptake and inflammatory response via TLR 4 to lipopolysaccharide (LPS and TiO2 NPs. In the case of LPS, LPS binds to LPS binding protein (LBP and CD 14, and then this complex binds to TLR 4. In the case of TiO2 NPs, the necessity of LBP and CD 14 to induce the inflammatory response and for uptake by cells was investigated using over-expression, antibody blocking, and siRNA knockdown experiments. Our results suggested that for cellular uptake of TiO2 NPs, TLR 4 did not form a complex with LBP and CD 14. In the TiO2 NP-mediated inflammatory response, TLR 4 acted as the signaling receptor without protein complex of LPS, LBP and CD 14. The results suggested that character of TiO2 NPs might be similar to the complex of LPS, LBP and CD 14. These results are important for development of safer nanomaterials.

  12. Cellular responses to modified Plasmodium falciparum MSP119 antigens in individuals previously exposed to natural malaria infection

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    Awobode Henrietta O

    2009-11-01

    Full Text Available Abstract Background MSP1 processing-inhibitory antibodies bind to epitopes on the 19 kDa C-terminal region of the Plasmodium falciparum merozoite surface protein 1 (MSP119, inhibiting erythrocyte invasion. Blocking antibodies also bind to this antigen but prevent inhibitory antibodies binding, allowing invasion to proceed. Recombinant MSP119 had been modified previously to allow inhibitory but not blocking antibodies to continue to bind. Immunization with these modified proteins, therefore, has the potential to induce more effective protective antibodies. However, it was unclear whether the modification of MSP119 would affect critical T-cell responses to epitopes in this antigen. Methods The cellular responses to wild-type MSP119 and a panel of modified MSP119 antigens were measured using an in-vitro assay for two groups of individuals: the first were malaria-naïve and the second had been naturally exposed to Plasmodium falciparum infection. The cellular responses to the modified proteins were examined using cells from malaria-exposed infants and adults. Results Interestingly, stimulation indices (SI for responses induced by some of the modified proteins were at least two-fold higher than those elicited by the wild-type MSP119. A protein with four amino acid substitutions (Glu27→Tyr, Leu31→Arg, Tyr34→Ser and Glu43→Leu had the highest stimulation index (SI up to 360 and induced large responses in 64% of the samples that had significant cellular responses to the modified proteins. Conclusion This study suggests that specific MSP119 variants that have been engineered to improve their antigenicity for inhibitory antibodies, retain T-cell epitopes and the ability to induce cellular responses. These proteins are candidates for the development of MSP1-based malaria vaccines.

  13. Autoinflammatory syndromes and cellular responses to stress: pathophysiology, diagnosis and new treatment perspectives.

    Science.gov (United States)

    Savic, Sinisa; Dickie, Laura J; Wittmann, Miriam; McDermott, Michael F

    2012-08-01

    The term 'autoinflammatory disease' was first proposed in 1999 to encompass some of the distinct clinicopathologic features of a group of monogenic conditions, characterised by recurrent episodes of inflammation, without high-titre autoantibodies or antigen-specific T cells. It was subsequently observed that several of these conditions were caused by mutations in proteins involved in the innate immune response, including, among others, components of the NLRP3 inflammasome, cytokine receptors (tumour necrosis factor receptor 1 (TNFR1)) and receptor antagonists (interleukin 1 receptor antagonist (IL-1RA)). More recently, additional mechanisms linking innate immune-mediated inflammation with a variety of cellular processes, including protein misfolding, oxidative stress and mitochondrial dysfunction, have been recognised to play a role in the pathogenesis of some monogenic autoinflammatory conditions, and also in more common diseases such as type 2 diabetes (T2D), previously perceived as a metabolic disorder, but reclassified as a chronic inflammatory condition. NLRP3 inflammasome activation is induced by islet amyloid polypeptides (IAPPs) in T2D and this condition may, in future, be more commonly treated with targeted anti-cytokine therapies. Caspase 1 activation and release of IL-1β/IL-1 family members is central to the pathogenesis of many autoinflammatory syndromes, as evidenced by the effectiveness of anti-IL-1 biologics in treating these disorders. However, many patients continue to experience symptoms of chronic inflammation, and it will be necessary to translate discoveries on the immunopathology of these conditions into more effective therapies. For example, in tumour necrosis factor receptor-associated periodic fever syndrome (TRAPS), the pathogenesis may vary with each mutation and therefore future approaches to treatment of individual patients will require a more tailored approach based on genetic and functional studies. Copyright © 2012 Elsevier Ltd

  14. The cellular stress response of rat skeletal muscle following lengthening contractions.

    Science.gov (United States)

    Pollock-Tahiri, Evan; Locke, Marius

    2017-07-01

    The cellular stress response of the rat tibialis anterior (TA) muscle was investigated following 20, 40, or 60 lengthening contractions (LCs) using an in vivo model of electrical stimulation. Muscles were removed at 0, 1, 3, or 24 h after LCs and assessed for heat shock transcription factor (HSF) activation, heat shock protein (HSP) content, and/or morphological evidence of muscle fibre damage. When compared with the first muscle contraction, peak muscle torque was reduced by 26% (p < 0.05) after 20 LCs and further reduced to 56% and 60% (p < 0.001) after 40 and 60 LCs, respectively. Following 60 LCs, HSF activation was detected at 0, 1, and 3 h but was undetectable at 24 h. Hsp72 content was elevated at 24 h after 20 LCs (2.34 ± 0.37 fold, p < 0.05), 40 LCs (3.02 ± 0.31 fold, p < 0.01), and 60 LCs (3.37 ± 0.21 fold, p < 0.001). Hsp25 content increased after 40 (2.36 ± 0.24 fold, p < 0.01) and 60 LCs (2.80 ± 0.37 fold, p < 0.01). Morphological assessment of TA morphology revealed that very few fibres were damaged following 20 LCs while multiple sets of LCs (40 and 60) caused greater amounts of fibre damage. Electron microscopy showed disrupted Z-lines and sarcomeres were detectable in some muscles fibres following 20 LCs but were more prevalent and severe in muscles subjected to 40 or 60 LCs. These results suggest LCs elevate HSP content by an HSF-mediated mechanism (60 LC) and a single set of 20 LCs is capable of increasing muscle HSP content without causing significant muscle fibre damage.

  15. The nucleotidohydrolases DCTPP1 and dUTPase are involved in the cellular response to decitabine.

    Science.gov (United States)

    Requena, Cristina E; Pérez-Moreno, Guiomar; Horváth, András; Vértessy, Beáta G; Ruiz-Pérez, Luis M; González-Pacanowska, Dolores; Vidal, Antonio E

    2016-09-01

    Decitabine (5-aza-2'-deoxycytidine, aza-dCyd) is an anti-cancer drug used clinically for the treatment of myelodysplastic syndromes and acute myeloid leukaemia that can act as a DNA-demethylating or genotoxic agent in a dose-dependent manner. On the other hand, DCTPP1 (dCTP pyrophosphatase 1) and dUTPase are two 'house-cleaning' nucleotidohydrolases involved in the elimination of non-canonical nucleotides. In the present study, we show that exposure of HeLa cells to decitabine up-regulates the expression of several pyrimidine metabolic enzymes including DCTPP1, dUTPase, dCMP deaminase and thymidylate synthase, thus suggesting their contribution to the cellular response to this anti-cancer nucleoside. We present several lines of evidence supporting that, in addition to the formation of aza-dCTP (5-aza-2'-deoxycytidine-5'-triphosphate), an alternative cytotoxic mechanism for decitabine may involve the formation of aza-dUMP, a potential thymidylate synthase inhibitor. Indeed, dUTPase or DCTPP1 down-regulation enhanced the cytotoxic effect of decitabine producing an accumulation of nucleoside triphosphates containing uracil as well as uracil misincorporation and double-strand breaks in genomic DNA. Moreover, DCTPP1 hydrolyses the triphosphate form of decitabine with similar kinetic efficiency to its natural substrate dCTP and prevents decitabine-induced global DNA demethylation. The data suggest that the nucleotidohydrolases DCTPP1 and dUTPase are factors involved in the mode of action of decitabine with potential value as enzymatic targets to improve decitabine-based chemotherapy.

  16. Mitochondrial GPX1 silencing triggers differential photosynthesis impairment in response to salinity in rice plants.

    Science.gov (United States)

    Lima-Melo, Yugo; Carvalho, Fabricio E L; Martins, Márcio O; Passaia, Gisele; Sousa, Rachel H V; Neto, Milton C Lima; Margis-Pinheiro, Márcia; Silveira, Joaquim A G

    2016-08-01

    The physiological role of plant mitochondrial glutathione peroxidases is scarcely known. This study attempted to elucidate the role of a rice mitochondrial isoform (GPX1) in photosynthesis under normal growth and salinity conditions. GPX1 knockdown rice lines (GPX1s) were tested in absence and presence of 100 mM NaCl for 6 d. Growth reduction of GPX1s line under non-stressful conditions, compared with non-transformed (NT) plants occurred in parallel to increased H2 O2 and decreased GSH contents. These changes occurred concurrently with photosynthesis impairment, particularly in Calvin cycle's reactions, since photochemical efficiency did not change. Thus, GPX1 silencing and downstream molecular/metabolic changes modulated photosynthesis differentially. In contrast, salinity induced reduction in both phases of photosynthesis, which were more impaired in silenced plants. These changes were associated with root morphology alterations but not shoot growth. Both studied lines displayed increased GPX activity but H2 O2 content did not change in response to salinity. Transformed plants exhibited lower photorespiration, water use efficiency and root growth, indicating that GPX1 could be important to salt tolerance. Growth reduction of GPX1s line might be related to photosynthesis impairment, which in turn could have involved a cross talk mechanism between mitochondria and chloroplast originated from redox changes due to GPX1 deficiency.

  17. The effect of oral consumption of shark cartilage on the cellular immune responses of cancer patients

    Directory of Open Access Journals (Sweden)

    somaye Shahrokhi

    2006-11-01

    Conclusion: It seems that shark cartilage could help strengthen cellular immunity which is important in tumor regression in breast cancer patients. So we suppose that it could be a good candidate for cancer treatment along with conventional medicine.

  18. Responsiveness of the Multiple Sclerosis Impairment Scale in comparison with the Expanded Disability Status Scale

    DEFF Research Database (Denmark)

    Ravnborg, M; Blinkenberg, M; Sellebjerg, F;

    2005-01-01

    The Multiple Sclerosis Impairment Scale (MSIS) is a measure of accumulated deficits assessed by means of a standard neurological examination. We compared the responsiveness of the MSIS with that of the Expanded Disability Status Scale (EDSS). We reviewed 4300 records collected systematically from...... 1995 to 2003 and identified 534 patients who had clinically definite multiple sclerosis and had had at least two clinical assessments with a time interval of 2-5 years. The rate of deterioration was significantly higher on the MSIS than on the EDSS. The annualized change in EDSS exhibited a maximum...

  19. Physiological, molecular, and cellular mechanisms of impaired seawater tolerance following exposure of Atlantic salmon, Salmo salar, smolts to acid and aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Monette, Michelle Y., E-mail: michelle.monette@yale.edu [Organismic and Evolutionary Biology Program, University of Massachusetts, Amherst, MA 01003 (United States); USGS, Conte Anadromous Fish Research Center, Turners Falls, MA 01376 (United States); Yada, Takashi [Freshwater Fisheries Research Department, National Research Institute of Fisheries Science, Nikko (Japan); Matey, Victoria [Department of Biology, San Diego State University, San Diego, CA 92182 (United States); McCormick, Stephen D. [Organismic and Evolutionary Biology Program, University of Massachusetts, Amherst, MA 01003 (United States); USGS, Conte Anadromous Fish Research Center, Turners Falls, MA 01376 (United States)

    2010-08-01

    We examined the physiological, molecular, and cellular mechanisms of impaired ion regulation in Atlantic salmon, Salmo salar, smolts following acute acid and aluminum (Al) exposure. Smolts were exposed to: control (pH 6.5, 3.4 {mu}g l{sup -1} Al), acid and low Al (LAl: pH 5.4, 11 {mu}g l{sup -1} Al), acid and moderate Al (MAl: pH 5.3, 42 {mu}g l{sup -1} Al), and acid and high Al (HAl: pH 5.4, 56 {mu}g l{sup -1} Al) for two and six days. At each time-point, smolts were sampled directly from freshwater treatment tanks and after a 24 h seawater challenge. Exposure to acid/MAl and acid/HAl led to accumulation of gill Al, substantial alterations in gill morphology, reduced gill Na{sup +}/K{sup +}-ATPase (NKA) activity, and impaired ion regulation in both freshwater and seawater. Exposure to acid/MAl for six days also led to a decrease in gill mRNA expression of the apical Cl{sup -} channel (cystic fibrosis transmembrane conductance regulator I), increased apoptosis upon seawater exposure, an increase in the surface expression of mitochondria-rich cells (MRCs) within the filament epithelium of the gill, but reduced abundance of gill NKA-positive MRCs. By contrast, smolts exposed to acid and the lowest Al concentration exhibited minor gill Al accumulation, slight morphological modifications in the gill, and impaired seawater tolerance in the absence of a detectable effect on freshwater ion regulation. These impacts were accompanied by decreased cell proliferation, a slight increase in the surface expression of MRCs within the filament epithelium, but no impact on gill apoptosis or total MRC abundance was observed. However, MRCs in the gills of smolts exposed to acid/LAl exhibited morphological alterations including decreased size, staining intensity, and shape factor. We demonstrate that the seawater tolerance of Atlantic salmon smolts is extremely sensitive to acute exposure to acid and low levels of Al, and that the mechanisms underlying this depend on the time

  20. Activation of WIP1 phosphatase by HTLV-1 Tax mitigates the cellular response to DNA damage.

    Directory of Open Access Journals (Sweden)

    Tajhal Dayaram

    Full Text Available Genomic instability stemming from dysregulation of cell cycle checkpoints and DNA damage response (DDR is a common feature of many cancers. The cancer adult T cell leukemia (ATL can occur in individuals infected with human T cell leukemia virus type 1 (HTLV-1, and ATL cells contain extensive chromosomal abnormalities, suggesting that they have defects in the recognition or repair of DNA damage. Since Tax is the transforming protein encoded by HTLV-1, we asked whether Tax can affect cell cycle checkpoints and the DDR. Using a combination of flow cytometry and DNA repair assays we showed that Tax-expressing cells exit G(1 phase and initiate DNA replication prematurely following damage. Reduced phosphorylation of H2AX (γH2AX and RPA2, phosphoproteins that are essential to properly initiate the DDR, was also observed in Tax-expressing cells. To determine the cause of decreased DDR protein phosphorylation in Tax-expressing cells, we examined the cellular phosphatase, WIP1, which is known to dephosphorylate γH2AX. We found that Tax can interact with Wip1 in vivo and in vitro, and that Tax-expressing cells display elevated levels of Wip1 mRNA. In vitro phosphatase assays showed that Tax can enhance Wip1 activity on a γH2AX peptide target by 2-fold. Thus, loss of γH2AX in vivo could be due, in part, to increased expression and activity of WIP1 in the presence of Tax. siRNA knockdown of WIP1 in Tax-expressing cells rescued γH2AX in response to damage, confirming the role of WIP1 in the DDR. These studies demonstrate that Tax can disengage the G(1/S checkpoint by enhancing WIP1 activity, resulting in reduced DDR. Premature G(1 exit of Tax-expressing cells in the presence of DNA lesions creates an environment that tolerates incorporation of random mutations into the host genome.

  1. Effects of levamisole hydrochloride on cellular immune response and flock performance of commercial broilers

    Directory of Open Access Journals (Sweden)

    OA Oladele

    2012-12-01

    Full Text Available Levamisole hydrochloride (Lev.HCl has been acclaimed to boost immune response particularly in immunocompromised state. Its routine use as an immunomodulator in poultry production is yet to be well embraced, thus its effects of on cellular immunity and flock performance of commercial broilers were evaluated. One hundred and fifty Anak broiler chicks were separated into two groups of 75 each. Broilers in group 1 were sensitized with 150µg of Staphylococcus aureus antigen each at 4 and 5 weeks, while those in group 2 were not sensitized. Each group was further divided into subgroups A, B, and C. Levamisole hydrochloride (40 mg/kg was administered orally to 1A and 2A at 45 and 46 days of age and to 1B and 2B at 47 and 48 days of age, while 1C and 2C were not treated. At 47 days of age, 12 broilers from all subgroups were challenged with 75µg of S. aureus antigen each at the right wattle. Wattle thickness was measured till 72 hours post challenge (pc and delayed wattle reaction (DWR was determined. Tissues were harvested at 72 hours pc for histopathology. Morbidity, mortality and live weights at 8 weeks of age were recorded. DWR peaked at 4 hours pc in 1A (2.22 ± 0.21 mm and 1B (2.96 ± 0.21 mm and 24 hours pc in 1C (3.39 ± 0.34 mm, the difference being significant (p<0.05. Inflammatory lesions were observed in wattles of sensitized subgroups and were more severe in 1C. Mortality rates were 4.17% and 29.17% in 1A and 1C respectively. Mean live weights in A and B i.e. 1.57± 0.06 kg and 1.56 ± 0.06 kg respectively, were significantly higher (p<0.0 than 1.43 ± 0.08 kg in C. Levamisole enhanced DTH via an early response, improved broiler liveability, and its anti-inflammatory property was confirmed.

  2. The cellular immune response plays an important role in protecting against dengue virus in the mouse encephalitis model.

    Science.gov (United States)

    Gil, Lázaro; López, Carlos; Blanco, Aracelys; Lazo, Laura; Martín, Jorge; Valdés, Iris; Romero, Yaremis; Figueroa, Yassel; Guillén, Gerardo; Hermida, Lisset

    2009-02-01

    For several years, researchers have known that the generation of neutralizing antibodies is a prerequisite for attaining adequate protection against dengue virus. Nevertheless, the cellular immune response is the principal arm of the adaptive immune system against non-cytopathic viruses such as dengue, as once the virus enters into the cell it is necessary to destroy it to eliminate the virus. To define the role of the cellular immune response in the protection against dengue, we selected the mouse encephalitis model. Mice were immunized with a single dose of infective dengue 2 virus and different markers of both branches of the induced adaptive immunity were measured. Animals elicited a broad antibody response against the four dengue virus serotypes, but neutralizing activity was only detected against the homologous serotype. On the other hand, the splenocytes of the infected animals strongly proliferated after in vitro stimulation with the homologous virus, and specifically the CD8 T-cell subset was responsible for the secretion of the cytokine IFN-gamma. Finally, to define the role of T cells in in vivo protection, groups of animals were inoculated with the depleting monoclonal antibodies anti-CD4 or anti-CD8. Only depletion with anti-CD8 decreased to 50% the level of protection reached in the non-depleted mice. The present work constitutes the first report defining the role of the cellular immune response in protection against dengue virus in the mouse model.

  3. Adaptive Posttranslational Control in Cellular Stress Response Pathways and Its Relationship to Toxicity Testing and Safety Assessment.

    Science.gov (United States)

    Zhang, Qiang; Bhattacharya, Sudin; Pi, Jingbo; Clewell, Rebecca A; Carmichael, Paul L; Andersen, Melvin E

    2015-10-01

    Although transcriptional induction of stress genes constitutes a major cellular defense program against a variety of stressors, posttranslational control directly regulating the activities of preexisting stress proteins provides a faster-acting alternative response. We propose that posttranslational control is a general adaptive mechanism operating in many stress pathways. Here with the aid of computational models, we first show that posttranslational control fulfills two roles: (1) handling small, transient stresses quickly and (2) stabilizing the negative feedback transcriptional network. We then review the posttranslational control pathways for major stress responses-oxidative stress, metal stress, hyperosmotic stress, DNA damage, heat shock, and hypoxia. Posttranslational regulation of stress protein activities occurs by reversible covalent modifications, allosteric or non-allosteric enzymatic regulations, and physically induced protein structural changes. Acting in feedback or feedforward networks, posttranslational control may establish a threshold level of cellular stress. Sub-threshold stresses are handled adequately by posttranslational control without invoking gene transcription. With supra-threshold stress levels, cellular homeostasis cannot be maintained and transcriptional induction of stress genes and other gene programs, eg, those regulating cell metabolism, proliferation, and apoptosis, takes place. The loss of homeostasis with consequent changes in cellular function may lead to adverse cellular outcomes. Overall, posttranslational and transcriptional control pathways constitute a stratified cellular defense system, handling stresses coherently across time and intensity. As cell-based assays become a focus for chemical testing anchored on toxicity pathways, examination of proteomic and metabolomic changes as a result of posttranslational control occurring in the absence of transcriptomic alterations deserves more attention. © The Author 2015

  4. Interleukin-27 inhibits vaccine-enhanced pulmonary disease following respiratory syncytial virus infection by regulating cellular memory responses.

    Science.gov (United States)

    Zeng, Ruihong; Zhang, Huixian; Hai, Yan; Cui, Yuxiu; Wei, Lin; Li, Na; Liu, Jianxun; Li, Caixia; Liu, Ying

    2012-04-01

    Respiratory syncytial virus (RSV) is the most important cause of lower respiratory tract disease in young children. In the 1960s, infants vaccinated with formalin-inactivated RSV developed a more severe disease characterized by excessive inflammatory immunopathology in lungs upon natural RSV infection. The fear of causing the vaccine-enhanced disease (VED) is an important obstacle for development of safe and effective RSV vaccines. The recombinant vaccine candidate G1F/M2 immunization also led to VED. It has been proved that cellular memory induced by RSV vaccines contributed to VED. Interleukin-27 (IL-27) and IL-23 regulate Th1, Th17, and/or Th2 cellular immune responses. In this study, mice coimmunized with pcDNA3-IL-27 and G1F/M2 were fully protected and, importantly, did not develop vaccine-enhanced inflammatory responses and immunopathology in lungs after RSV challenge, which was correlated with moderate Th1-, suppressed Th2-, and Th17-like memory responses activated by RSV. In contrast, G1F/M2- or pcDNA3-IL-23+G1F/M2-immunized mice, in which robust Th2- and Th17-like memory responses were induced, developed enhanced pulmonary inflammation and severe immunopathology. Mice coimmunized with G1F/M2 and the two cytokine plasmids exhibited mild inflammatory responses as well as remarkable Th1-, suppressed Th2-, and Th17-like memory responses. These results suggested that Th1-, Th2-, and Th17-like memory responses and, in particular, excessive Th2- and Th17-like memory responses were closely associated with VED; IL-27 may inhibit VED following respiratory syncytial virus infection by regulating cellular memory responses.

  5. The interplay among chromatin dynamics, cell cycle checkpoints and repair mechanisms modulates the cellular response to DNA damage.

    Science.gov (United States)

    Lazzaro, Federico; Giannattasio, Michele; Muzi-Falconi, Marco; Plevani, Paolo

    2007-06-01

    Cells are continuously under the assault of endogenous and exogenous genotoxic stress that challenges the integrity of DNA. To cope with such a formidable task cells have evolved surveillance mechanisms, known as checkpoints, and a variety of DNA repair systems responding to different types of DNA lesions. These lesions occur in the context of the chromatin structure and, as expected for all DNA transactions, the cellular response to DNA damage is going to be influenced by the chromatin enviroment. In this review, we will discuss recent studies implicating chromatin remodelling factors and histone modifications in the response to DNA double-strand breaks (DSBs) and in checkpoint activation in response to UV lesions.

  6. Toxicity potentials from waste cellular phones, and a waste management policy integrating consumer, corporate, and government responsibilities.

    Science.gov (United States)

    Lim, Seong-Rin; Schoenung, Julie M

    2010-01-01

    Cellular phones have high environmental impact potentials because of their heavy metal content and current consumer attitudes toward purchasing new phones with higher functionality and neglecting to return waste phones into proper take-back systems. This study evaluates human health and ecological toxicity potentials from waste cellular phones; highlights consumer, corporate, and government responsibilities for effective waste management; and identifies key elements needed for an effective waste management strategy. The toxicity potentials are evaluated by using heavy metal content, respective characterization factors, and a pathway and impact model for heavy metals that considers end-of-life disposal in landfills or by incineration. Cancer potentials derive primarily from Pb and As; non-cancer potentials primarily from Cu and Pb; and ecotoxicity potentials primarily from Cu and Hg. These results are not completely in agreement with previous work in which leachability thresholds were the metric used to establish priority, thereby indicating the need for multiple or revised metrics. The triple bottom line of consumer, corporate, and government responsibilities is emphasized in terms of consumer attitudes, design for environment (DfE), and establishment and implementation of waste management systems including recycling streams, respectively. The key strategic elements for effective waste management include environmental taxation and a deposit-refund system to motivate consumer responsibility, which is linked and integrated with corporate and government responsibilities. The results of this study can contribute to DfE and waste management policy for cellular phones. 2010 Elsevier Ltd. All rights reserved.

  7. Frontal White Matter Damage Impairs Response Inhibition in Children Following Traumatic Brain Injury

    Science.gov (United States)

    Lipszyc, Jonathan; Levin, Harvey; Hanten, Gerri; Hunter, Jill; Dennis, Maureen; Schachar, Russell

    2014-01-01

    Inhibition, the ability to suppress inappropriate cognitions or behaviors, can be measured using computer tasks and questionnaires. Inhibition depends on the frontal cortex, but the role of the underlying white matter (WM) is unclear. We assessed the specific impact of frontal WM damage on inhibition in 29 children with moderate-to-severe traumatic brain injury (15 with and 14 without frontal WM damage), 21 children with orthopedic injury, and 29 population controls. We used the Stop Signal Task to measure response inhibition, the Behavior Rating Inventory of Executive Function to assess everyday inhibition, and T2 fluid-attenuated inversion recovery magnetic resonance imaging to identify lesions. Children with frontal WM damage had impaired response inhibition compared with all other groups and poorer everyday inhibition than the orthopedic injury group. Frontal WM lesions most often affected the superior frontal gyrus. These results provide evidence for the critical role of frontal WM in inhibition. PMID:24618405

  8. 5-Lipoxygenase deficiency impairs innate and adaptive immune responses during fungal infection.

    Directory of Open Access Journals (Sweden)

    Adriana Secatto

    Full Text Available 5-Lipoxygenase-derived products have been implicated in both the inhibition and promotion of chronic infection. Here, we sought to investigate the roles of endogenous 5-lipoxygenase products and exogenous leukotrienes during Histoplasma capsulatum infection in vivo and in vitro. 5-LO deficiency led to increased lung CFU, decreased nitric oxide production and a deficient primary immune response during active fungal infection. Moreover, H. capsulatum-infected 5-LO(-/- mice showed an intense influx of neutrophils and an impaired ability to generate and recruit effector T cells to the lung. The fungal susceptibility of 5-LO(-/- mice correlated with a lower rate of macrophage ingestion of IgG-H. capsulatum relative to WT macrophages. Conversely, exogenous LTB4 and LTC4 restored macrophage phagocytosis in 5-LO deficient mice. Our results demonstrate that leukotrienes are required to control chronic fungal infection by amplifying both the innate and adaptive immune response during histoplasmosis.

  9. Impaired glucose-induced thermogenesis and arterial norepinephrine response persist after weight reduction in obese humans

    DEFF Research Database (Denmark)

    Astrup, A; Andersen, T; Christensen, N J;

    1990-01-01

    A reduced thermic response and an impaired activation of the sympathetic nervous system (SNS) has been reported after oral glucose in human obesity. It is, however, not known whether the reduced SNS activity returns to normal along with weight reduction. The thermic effect of glucose was lower...... in eight obese patients than in matched control subjects (1.7% vs 9.2%, p less than 0.002). The increase in arterial norepinephrine after glucose was also blunted in the obese patients. After a 30-kg weight loss their glucose and lipid profiles were markedly improved but the thermic effect of glucose...... was still lower than that of the control subjects (4.2%, p less than 0.001). The glucose-induced arterial norepinephrine response remained diminished in the reduced obese patients whereas the changes in plasma epinephrine were similar in all three groups. The results suggest that a defective SNS may...

  10. Transient Dysregulation of Dopamine Signaling in a Developing Drosophila Arousal Circuit Permanently Impairs Behavioral Responsiveness in Adults

    Science.gov (United States)

    Ferguson, Lachlan; Petty, Alice; Rohrscheib, Chelsie; Troup, Michael; Kirszenblat, Leonie; Eyles, Darryl W.; van Swinderen, Bruno

    2017-01-01

    The dopamine ontogeny hypothesis for schizophrenia proposes that transient dysregulation of the dopaminergic system during brain development increases the likelihood of this disorder in adulthood. To test this hypothesis in a high-throughput animal model, we have transiently manipulated dopamine signaling in the developing fruit fly Drosophila melanogaster and examined behavioral responsiveness in adult flies. We found that either a transient increase of dopamine neuron activity or a transient decrease of dopamine receptor expression during fly brain development permanently impairs behavioral responsiveness in adults. A screen for impaired responsiveness revealed sleep-promoting neurons in the central brain as likely postsynaptic dopamine targets modulating these behavioral effects. Transient dopamine receptor knockdown during development in a restricted set of ~20 sleep-promoting neurons recapitulated the dopamine ontogeny phenotype, by permanently reducing responsiveness in adult animals. This suggests that disorders involving impaired behavioral responsiveness might result from defective ontogeny of sleep/wake circuits. PMID:28243212

  11. Old age and the associated impairment of bones' adaptation to loading are associated with transcriptomic changes in cellular metabolism, cell-matrix interactions and the cell cycle.

    Science.gov (United States)

    Galea, Gabriel L; Meakin, Lee B; Harris, Marie A; Delisser, Peter J; Lanyon, Lance E; Harris, Stephen E; Price, Joanna S

    2017-01-30

    In old animals, bone's ability to adapt its mass and architecture to functional load-bearing requirements is diminished, resulting in bone loss characteristic of osteoporosis. Here we investigate transcriptomic changes associated with this impaired adaptive response. Young adult (19-week-old) and aged (19-month-old) female mice were subjected to unilateral axial tibial loading and their cortical shells harvested for microarray analysis between 1h and 24h following loading (36 mice per age group, 6 mice per loading group at 6 time points). In non-loaded aged bones, down-regulated genes are enriched for MAPK, Wnt and cell cycle components, including E2F1. E2F1 is the transcription factor most closely associated with genes down-regulated by ageing and is down-regulated at the protein level in osteocytes. Genes up-regulated in aged bone are enriched for carbohydrate metabolism, TNFα and TGFβ superfamily components. Loading stimulates rapid and sustained transcriptional responses in both age groups. However, genes related to proliferation are predominantly up-regulated in the young and down-regulated in the aged following loading, whereas those implicated in bioenergetics are down-regulated in the young and up-regulated in the aged. Networks of inter-related transcription factors regulated by E2F1 are loading-responsive in both age groups. Loading regulates genes involved in similar signalling cascades in both age groups, but these responses are more sustained in the young than aged. From this we conclude that cells in aged bone retain the capability to sense and transduce loading-related stimuli, but their ability to translate acute responses into functionally relevant outcomes is diminished.

  12. SINGLE-CELL LEVEL INVESTIGATION OF CYTOSKELETAL/CELLULAR RESPONSE TO EXTERNAL STIMULI

    Energy Technology Data Exchange (ETDEWEB)

    Hiddessen, A L

    2007-02-26

    A detailed understanding of the molecular mechanisms by which chemical signals control cell behavior is needed if the complex biological processes of embryogenesis, development, health and disease are to be completely understood. Yet, if we are to fully understand the molecular mechanisms controlling cell behavior, measurements at the single cell level are needed to supplement information gained from population level studies. One of the major challenges to accomplishing studies at the single cell level has been a lack of physical tools to complement the powerful molecular biological assays which have provided much of what we currently know about cell behavior. The goal of this exploratory project is the development of an experimental platform that facilitates integrated observation, tracking and analysis of the responses of many individual cells to controlled environmental factors (e.g. extracellular signals). Toward this goal, we developed chemically-patterned microarrays of both adherent and suspension mammalian cell types. A novel chemical patterning methodology, based on photocatalytic lithography, was developed to construct biomolecule and cell arrays that facilitate analysis of biological function. Our patterning techniques rely on inexpensive stamp materials and visible light, and do not necessitate mass transport or specified substrates. Patterned silicon and glass substrates are modified such that there is a non-biofouling polymer matrix surrounding the adhesive regions that target biomolecules and cells. Fluorescence and reflectance microscopy reveal successful patterning of proteins and single to small clusters of mammalian cells. In vitro assays conducted upon cells on the patterned arrays demonstrate the viability of cells interfacing with this synthetic system. Hence, we have successfully established a versatile cell measurement platform which can be used to characterize the molecular regulators of cellular behavior in a variety of important

  13. Regulation of Cellular Response Pattern to Phosphorus Ion is a New Target for the Design of Tissue-Engineered Blood Vessel.

    Science.gov (United States)

    Chen, Wen; Wang, Fangjuan; Zeng, Wen; Sun, Jun; Li, Li; Yang, Mingcan; Sun, Jiansen; Wu, Yangxiao; Zhao, Xiaohui; Zhu, Chuhong

    2015-05-01

    Regulation of cellular response pattern to phosphorus ion (PI) is a new target for the design of tissue-engineered materials. Changing cellular response pattern to high PI can maintain monocyte/macrophage survival in TEBV and the signal of increasing PI can be converted by klotho to the adenosine signals through the regulation of energy metabolism in monocytes/macrophages.

  14. A cellular stress response (CSR) that interacts with NADPH-P450 reductase (NPR) is a new regulator of hypoxic response.

    Science.gov (United States)

    Oguro, Ami; Koyama, Chika; Xu, Jing; Imaoka, Susumu

    2014-02-28

    NADPH-P450 reductase (NPR) was previously found to contribute to the hypoxic response of cells, but the mechanism was not clarified. In this study, we identified a cellular stress response (CSR) as a new factor interacting with NPR by a yeast two-hybrid system. Overexpression of CSR enhanced the induction of erythropoietin and hypoxia response element (HRE) activity under hypoxia in human hepatocarcinoma cell lines (Hep3B), while knockdown of CSR suppressed them. This new finding regarding the interaction of NPR with CSR provides insight into the function of NPR in hypoxic response.

  15. Sublethal pesticide doses negatively affect survival and the cellular responses in American foulbrood-infected honeybee larvae

    Science.gov (United States)

    López, Javier Hernández; Krainer, Sophie; Engert, Antonia; Schuehly, Wolfgang; Riessberger-Gallé, Ulrike; Crailsheim, Karl

    2017-02-01

    Disclosing interactions between pesticides and bee infections is of most interest to understand challenges that pollinators are facing and to which extent bee health is compromised. Here, we address the individual and combined effect that three different pesticides (dimethoate, clothianidin and fluvalinate) and an American foulbrood (AFB) infection have on mortality and the cellular immune response of honeybee larvae. We demonstrate for the first time a synergistic interaction when larvae are exposed to sublethal doses of dimethoate or clothianidin in combination with Paenibacillus larvae, the causative agent of AFB. A significantly higher mortality than the expected sum of the effects of each individual stressor was observed in co-exposed larvae, which was in parallel with a drastic reduction of the total and differential hemocyte counts. Our results underline that characterizing the cellular response of larvae to individual and combined stressors allows unmasking previously undetected sublethal effects of pesticides in colony health.

  16. Familial Parkinson's disease iPSCs show cellular deficits in mitochondrial responses that can be pharmacologically rescued

    Science.gov (United States)

    Cooper, Oliver; Seo, Hyemyung; Andrabi, Shaida; Guardia-Laguarta, Cristina; Graziotto, John; Sundberg, Maria; McLean, Jesse R.; Carrillo-Reid, Luis; Xie, Zhong; Osborn, Teresia; Hargus, Gunnar; Deleidi, Michela; Lawson, Tristan; Bogetofte, Helle; Perez-Torres, Eduardo; Clark, Lorraine; Moskowitz, Carol; Mazzulli, Joseph; Chen, Li; Volpicelli-Daley, Laura; Romero, Norma; Jiang, Houbo; Uitti, Ryan J.; Huang, Zhigao; Opala, Grzegorz; Scarffe, Leslie A.; Dawson, Valina L.; Klein, Christine; Feng, Jian; Ross, Owen A.; Trojanowski, John Q.; Lee, Virginia M.-Y.; Marder, Karen; Surmeier, D. James; Wszolek, Zbigniew K.; Przedborski, Serge; Krainc, Dimitri; Dawson, Ted M.; Isacson, Ole

    2012-01-01

    Parkinson's disease (PD) is a common neurodegenerative disease caused by genetic and environmental factors. We analyzed induced pluripotent stem cell (iPSC)-derived neural cells from PD patients and presymptomatic individuals carrying mutations in the PINK1 and LRRK2 genes, and healthy control subjects. We measured several aspects of mitochondrial responses in the iPSC-derived neural cells including production of reactive oxygen species, mitochondrial respiration, proton leakage and intraneuronal movement of mitochondria. Cellular vulnerability associated with mitochondrial function in iPSC-derived neural cells from PD patients and at-risk individuals could be rescued with coenzyme Q10, rapamycin or the LRRK2 kinase inhibitor GW5074. Analysis of mitochondrial responses in iPSC-derived neural cells from PD patients carrying different mutations provides insights into convergence of cellular disease mechanisms between different familial forms of PD and highlights the importance of oxidative stress and mitochondrial dysfunction in PD. PMID:22764206

  17. Development of mechano-responsive polymeric scaffolds using functionalized silica nano-fillers for the control of cellular functions.

    Science.gov (United States)

    Griffin, Michelle; Nayyer, Leila; Butler, Peter E; Palgrave, Robert G; Seifalian, Alexander M; Kalaskar, Deepak M

    2016-08-01

    We demonstrate an efficient method to produce mechano-responsive polymeric scaffolds which can alter cellular functions using two different functionalized (OH and NH2) silica nano-fillers. Fumed silica-hydroxyl and fumed silica-amine nano-fillers were mixed with a biocompatible polymer (POSS-PCU) at various wt% to produce scaffolds. XPS and mechanical testing demonstrate that bulk mechanical properties are modified without changing the scaffold's surface chemistry. Mechanical testing showed significant change in bulk properties of POSS-PCU scaffolds with an addition of silica nanofillers as low as 1% (PScaffolds modified with NH2 silica showed significantly higher bulk mechanical properties compared to the one modified with the OH group. Enhanced cell adhesion, proliferation and collagen production over 14days were observed on scaffolds with higher bulk mechanical properties (NH2) compared to those with lower ones (unmodified and OH modified) (Ppolymeric scaffolds, which can help to customize cellular responses for biomaterial applications.

  18. Sublethal pesticide doses negatively affect survival and the cellular responses in American foulbrood-infected honeybee larvae

    Science.gov (United States)

    López, Javier Hernández; Krainer, Sophie; Engert, Antonia; Schuehly, Wolfgang; Riessberger-Gallé, Ulrike; Crailsheim, Karl

    2017-01-01

    Disclosing interactions between pesticides and bee infections is of most interest to understand challenges that pollinators are facing and to which extent bee health is compromised. Here, we address the individual and combined effect that three different pesticides (dimethoate, clothianidin and fluvalinate) and an American foulbrood (AFB) infection have on mortality and the cellular immune response of honeybee larvae. We demonstrate for the first time a synergistic interaction when larvae are exposed to sublethal doses of dimethoate or clothianidin in combination with Paenibacillus larvae, the causative agent of AFB. A significantly higher mortality than the expected sum of the effects of each individual stressor was observed in co-exposed larvae, which was in parallel with a drastic reduction of the total and differential hemocyte counts. Our results underline that characterizing the cellular response of larvae to individual and combined stressors allows unmasking previously undetected sublethal effects of pesticides in colony health. PMID:28145462

  19. Proteomic analysis of cellular response induced by boron neutron capture reaction in human squamous cell carcinoma SAS cells.

    Science.gov (United States)

    Sato, Akira; Itoh, Tasuku; Imamichi, Shoji; Kikuhara, Sota; Fujimori, Hiroaki; Hirai, Takahisa; Saito, Soichiro; Sakurai, Yoshinori; Tanaka, Hiroki; Nakamura, Hiroyuki; Suzuki, Minoru; Murakami, Yasufumi; Baiseitov, Diaz; Berikkhanova, Kulzhan; Zhumadilov, Zhaxybay; Imahori, Yoshio; Itami, Jun; Ono, Koji; Masunaga, Shinichiro; Masutani, Mitsuko

    2015-12-01

    To understand the mechanism of cell death induced by boron neutron capture reaction (BNCR), we performed proteome analyses of human squamous tumor SAS cells after BNCR. Cells were irradiated with thermal neutron beam at KUR after incubation under boronophenylalanine (BPA)(+) and BPA(-) conditions. BNCR mainly induced typical apoptosis in SAS cells 24h post-irradiation. Proteomic analysis in SAS cells suggested that proteins functioning in endoplasmic reticulum, DNA repair, and RNA processing showed dynamic changes at early phase after BNCR and could be involved in the regulation of cellular response to BNCR. We found that the BNCR induces fragments of endoplasmic reticulum-localized lymphoid-restricted protein (LRMP). The fragmentation of LRMP was also observed in the rat tumor graft model 20 hours after BNCT treatment carried out at the National Nuclear Center of the Republic of Kazakhstan. These data suggest that dynamic changes of LRMP could be involved during cellular response to BNCR.

  20. Different decision deficits impair response inhibition in progressive supranuclear palsy and Parkinson's disease.

    Science.gov (United States)

    Zhang, Jiaxiang; Rittman, Timothy; Nombela, Cristina; Fois, Alessandro; Coyle-Gilchrist, Ian; Barker, Roger A; Hughes, Laura E; Rowe, James B

    2016-01-01

    Progressive supranuclear palsy and Parkinson's disease have distinct underlying neuropathology, but both diseases affect cognitive function in addition to causing a movement disorder. They impair response inhibition and may lead to impulsivity, which can occur even in the presence of profound akinesia and rigidity. The current study examined the mechanisms of cognitive impairments underlying disinhibition, using horizontal saccadic latencies that obviate the impact of limb slowness on executing response decisions. Nineteen patients with clinically diagnosed progressive supranuclear palsy (Richardson's syndrome), 24 patients with clinically diagnosed Parkinson's disease and 26 healthy control subjects completed a saccadic Go/No-Go task with a head-mounted infrared saccadometer. Participants were cued on each trial to make a pro-saccade to a horizontal target or withhold their responses. Both patient groups had impaired behavioural performance, with more commission errors than controls. Mean saccadic latencies were similar between all three groups. We analysed behavioural responses as a binary decision between Go and No-Go choices. By using Bayesian parameter estimation, we fitted a hierarchical drift-diffusion model to individual participants' single trial data. The model decomposes saccadic latencies into parameters for the decision process: decision boundary, drift rate of accumulation, decision bias, and non-decision time. In a leave-one-out three-way classification analysis, the model parameters provided better discrimination between patients and controls than raw behavioural measures. Furthermore, the model revealed disease-specific deficits in the Go/No-Go decision process. Both patient groups had slower drift rate of accumulation, and shorter non-decision time than controls. But patients with progressive supranuclear palsy were strongly biased towards a pro-saccade decision boundary compared to Parkinson's patients and controls. This indicates a prepotency of

  1. Integrative analysis of large scale expression profiles reveals core transcriptional response and coordination between multiple cellular processes in a cyanobacterium

    Directory of Open Access Journals (Sweden)

    Bhattacharyya-Pakrasi Maitrayee

    2010-08-01

    Full Text Available Abstract Background Cyanobacteria are the only known prokaryotes capable of oxygenic photosynthesis. They play significant roles in global biogeochemical cycles and carbon sequestration, and have recently been recognized as potential vehicles for production of renewable biofuels. Synechocystis sp. PCC 6803 has been extensively used as a model organism for cyanobacterial studies. DNA microarray studies in Synechocystis have shown varying degrees of transcriptome reprogramming under altered environmental conditions. However, it is not clear from published work how transcriptome reprogramming affects pre-existing networks of fine-tuned cellular processes. Results We have integrated 163 transcriptome data sets generated in response to numerous environmental and genetic perturbations in Synechocystis. Our analyses show that a large number of genes, defined as the core transcriptional response (CTR, are commonly regulated under most perturbations. The CTR contains nearly 12% of Synechocystis genes found on its chromosome. The majority of genes in the CTR are involved in photosynthesis, translation, energy metabolism and stress protection. Our results indicate that a large number of differentially regulated genes identified in most reported studies in Synechocystis under different perturbations are associated with the general stress response. We also find that a majority of genes in the CTR are coregulated with 25 regulatory genes. Some of these regulatory genes have been implicated in cellular responses to oxidative stress, suggesting that reactive oxygen species are involved in the regulation of the CTR. A Bayesian network, based on the regulation of various KEGG pathways determined from the expression patterns of their associated genes, has revealed new insights into the coordination between different cellular processes. Conclusion We provide here the first integrative analysis of transcriptome data sets generated in a cyanobacterium. This

  2. Increased cellular proliferation in rat skeletal muscle and tendon in response to exercise

    DEFF Research Database (Denmark)

    Skovgaard, Dorthe; Bayer, Monika L; Mackey, Abigail

    2010-01-01

    PURPOSE: The purpose of this study is to investigate exercise-induced cellular proliferation in rat skeletal muscle/tendon with the use of 3'-[F-18]fluoro-3'deoxythymidine (FLT) and to quantitatively study concomitant changes in the proliferation-associated factor, Ki67. PROCEDURES: Wistar rats (...

  3. Airway cellular response to two different immunosuppressive regimens in lung transplant recipients

    NARCIS (Netherlands)

    Slebos, DJ; Kauffman, HF; Koeter, GH; Verschuuren, EAM; van der Bij, W; Postma, DS

    2005-01-01

    A number of new immunosuppressive drugs have become available in transplant medicine. We investigated the effects of two different immunosuppressive protocols on bronchoalveolar lavage fluid cellular characteristics in 34 lung transplant recipients who were treated with anti-thymocyte globulin induc

  4. Adult neurogenesis and the unfolded protein response; new cellular and molecular avenues in sleep research

    NARCIS (Netherlands)

    Lucassen, P.J.; Scheper, W.; van Someren, E.J.W.

    2009-01-01

    Two recent publications in this journal highlight the impact of new developments for our understanding of the mechanisms underlying the consequences of sleep disturbance and sleep loss. Meerlo et al. discuss effects of sleep disturbance at the cellular level, focusing mainly on adult neurogenesis an

  5. Chemical Genomics Identifies the PERK-Mediated Unfolded Protein Stress Response as a Cellular Target for Influenza Virus Inhibition

    Directory of Open Access Journals (Sweden)

    Sara Landeras-Bueno

    2016-04-01

    Full Text Available Influenza A viruses generate annual epidemics and occasional pandemics of respiratory disease with important consequences for human health and the economy. Therefore, a large effort has been devoted to the development of new anti-influenza virus drugs directed to viral targets, as well as to the identification of cellular targets amenable to anti-influenza virus therapy. Here we have addressed the identification of such potential cellular targets by screening collections of drugs approved for human use. We reasoned that screening with a green fluorescent protein-based recombinant replicon system would identify cellular targets involved in virus transcription/replication and/or gene expression and hence address an early stage of virus infection. By using such a strategy, we identified Montelukast (MK as an inhibitor of virus multiplication. MK inhibited virus gene expression but did not alter viral RNA synthesis in vitro or viral RNA accumulation in vivo. The low selectivity index of MK prevented its use as an antiviral, but it was sufficient to identify a new cellular pathway suitable for anti-influenza virus intervention. By deep sequencing of RNA isolated from mock- and virus-infected human cells, treated with MK or left untreated, we showed that it stimulates the PERK-mediated unfolded protein stress response. The phosphorylation of PERK was partly inhibited in virus-infected cells but stimulated in MK-treated cells. Accordingly, pharmacological inhibition of PERK phosphorylation led to increased viral gene expression, while inhibition of PERK phosphatase reduced viral protein synthesis. These results suggest the PERK-mediated unfolded protein response as a potential cellular target to modulate influenza virus infection.

  6. IFI16, an amplifier of DNA-damage response: Role in cellular senescence and aging-associated inflammatory diseases.

    Science.gov (United States)

    Choubey, Divaker; Panchanathan, Ravichandran

    2016-07-01

    DNA-damage induces a DNA-damage response (DDR) in mammalian cells. The response, depending upon the cell-type and the extent of DNA-damage, ultimately results in cell death or cellular senescence. DDR-induced signaling in cells activates the ATM-p53 and ATM-IKKα/β-interferon (IFN)-β signaling pathways, thus leading to an induction of the p53 and IFN-inducible IFI16 gene. Further, upon DNA-damage, DNA accumulates in the cytoplasm, thereby inducing the IFI16 protein and STING-dependent IFN-β production and activation of the IFI16 inflammasome, resulting in the production of proinflammatory cytokines (e.g., IL-1β and IL-18). Increased expression of IFI16 protein in a variety of cell-types promotes cellular senescence. However, reduced expression of IFI16 in cells promotes cell proliferation. Because expression of the IFI16 gene is induced by activation of DNA-damage response in cells and increased levels of IFI16 protein in cells potentiate the p53-mediated transcriptional activation of genes and p53 and pRb-mediated cell cycle arrest, we discuss how an improved understanding of the role of IFI16 protein in cellular senescence and associated inflammatory secretory phenotype is likely to identify the molecular mechanisms that contribute to the development of aging-associated human inflammatory diseases and a failure to cancer therapy.

  7. Impaired leukocyte trafficking and skin inflammatory responses in hamsters lacking a functional circadian system.

    Science.gov (United States)

    Prendergast, Brian J; Cable, Erin J; Patel, Priyesh N; Pyter, Leah M; Onishi, Kenneth G; Stevenson, Tyler J; Ruby, Norman F; Bradley, Sean P

    2013-08-01

    The immune system is under strong circadian control, and circadian desynchrony is a risk factor for metabolic disorders, inflammatory responses and cancer. Signaling pathways that maintain circadian rhythms (CRs) in immune function in vivo, and the mechanisms by which circadian desynchrony impairs immune function, remain to be fully identified. These experiments tested the hypothesis that the hypothalamic circadian pacemaker in the suprachiasmatic nucleus (SCN) drives CRs in the immune system, using a non-invasive model of SCN circadian arrhythmia. Robust CRs in blood leukocyte trafficking, with a peak during the early light phase (ZT4) and nadir in the early dark phase (ZT18), were absent in arrhythmic hamsters, as were CRs in spleen clock gene (per1, bmal1) expression, indicating that a functional pacemaker in the SCN is required for the generation of CRs in leukocyte trafficking and for driving peripheral clocks in secondary lymphoid organs. Pinealectomy was without effect on CRs in leukocyte trafficking, but abolished CRs in spleen clock gene expression, indicating that nocturnal melatonin secretion is necessary for communicating circadian time information to the spleen. CRs in trafficking of antigen presenting cells (CD11c(+) dendritic cells) in the skin were abolished, and antigen-specific delayed-type hypersensitivity skin inflammatory responses were markedly impaired in arrhythmic hamsters. The SCN drives robust CRs in leukocyte trafficking and lymphoid clock gene expression; the latter of which is not expressed in the absence of melatonin. Robust entrainment of the circadian pacemaker provides a signal critical to diurnal rhythms in immunosurveilliance and optimal memory T-cell dependent immune responses. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Impaired mastication reduced newly generated neurons at the accessory olfactory bulb and pheromonal responses in mice.

    Science.gov (United States)

    Utsugi, Chizuru; Miyazono, Sadaharu; Osada, Kazumi; Matsuda, Mitsuyoshi; Kashiwayanagi, Makoto

    2014-12-01

    A large number of neurons are generated at the subventricular zone (SVZ) even during adulthood. In a previous study, we have shown that a reduced mastication impairs both neurogenesis in the SVZ and olfactory functions. Pheromonal signals, which are received by the vomeronasal organ, provide information about reproductive and social states. Vomeronasal sensory neurons project to the accessory olfactory bulb (AOB) located on the dorso-caudal surface of the main olfactory bulb. Newly generated neurons at the SVZ migrate to the AOB and differentiate into granule cells and periglomerular cells. This study aimed to explore the effects of changes in mastication on newly generated neurons and pheromonal responses. Bromodeoxyuridine-immunoreactive (BrdU-ir; a marker of DNA synthesis) and Fos-ir (a marker of neurons excited) structures in sagittal sections of the AOB after exposure to urinary odours were compared between the mice fed soft and hard diets. The density of BrdU-ir cells in the AOB in the soft-diet-fed mice after 1 month was essentially similar to that of the hard-diet-fed mice, while that was lower in the soft-diet-fed mice for 3 or 6 months than in the hard-diet-fed mice. The density of Fos-ir cells in the soft-diet-fed mice after 2 months was essentially similar to that in the hard-diet-fed mice, while that was lower in the soft-diet-fed mice for 4 months than in the hard-diet-fed mice. The present results suggest that impaired mastication reduces newly generated neurons at the AOB, which in turn impairs olfactory function at the AOB. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Identification of genes that regulate multiple cellular processes/responses in the context of lipotoxicity to hepatoma cells

    Directory of Open Access Journals (Sweden)

    Yedwabnick Matthew

    2007-10-01

    Full Text Available Abstract Background In order to devise efficient treatments for complex, multi-factorial diseases, it is important to identify the genes which regulate multiple cellular processes. Exposure to elevated levels of free fatty acids (FFAs and tumor necrosis factor alpha (TNF-α alters multiple cellular processes, causing lipotoxicity. Intracellular lipid accumulation has been shown to reduce the lipotoxicity of saturated FFA. We hypothesized that the genes which simultaneously regulate lipid accumulation as well as cytotoxicity may provide better targets to counter lipotoxicity of saturated FFA. Results As a model system to test this hypothesis, human hepatoblastoma cells (HepG2 were exposed to elevated physiological levels of FFAs and TNF-α. Triglyceride (TG accumulation, toxicity and the genomic responses to the treatments were measured. Here, we present a framework to identify such genes in the context of lipotoxicity. The aim of the current study is to identify the genes that could be altered to treat or ameliorate the cellular responses affected by a complex disease rather than to identify the causal genes. Genes that regulate the TG accumulation, cytotoxicity or both were identified by a modified genetic algorithm partial least squares (GA/PLS analysis. The analyses identified NADH dehydrogenase and mitogen activated protein kinases (MAPKs as important regulators of both cytotoxicity and lipid accumulation in response to FFA and TNF-α exposure. In agreement with the predictions, inhibiting NADH dehydrogenase and c-Jun N-terminal kinase (JNK reduced cytotoxicity significantly and increased intracellular TG accumulation. Inhibiting another MAPK pathway, the extracellular signal regulated kinase (ERK, on the other hand, improved the cytotoxicity without changing TG accumulation. Much greater reduction in the toxicity was observed upon inhibiting the NADH dehydrogenase and MAPK (which were identified by the dual-response analysis, than for the

  10. Postsplenectomy cytomegaloviral mononucleosis: marked lymphocytosis, TCRgamma gene rearrangements, and impaired IgM response.

    Science.gov (United States)

    Han, Xiang Y; Lin, Pei; Amin, Hesham M; Ferrajoli, Alessandra

    2005-04-01

    People who have undergone splenectomy mount a poor IgM response to bacterial polysaccharide vaccines. Whether this defect is true during natural bacterial and viral infections is unknown. We present 2 cases of postsplenectomy cytomegalovirus (CMV)-induced mononucleosis with impaired IgM but normal to augmented IgG response. The cases presented initial diagnostic challenges owing to a prolonged course of infection, marked lymphocytosis (peak lymphocyte count, 27,900/microL [27.9 10(9)/L]), clonal T-cell proliferation with T-cell receptor g gene rearrangements, and remote history of splenectomy. However, the acute nature of the infections, serial determinations of the anti-CMV IgM and IgG, exclusion of other causes, and detection of CMV in the blood established the diagnosis and revealed the deranged antibody response. The infections resolved without specific treatment. These cases suggest that the spleen might be a primary site for specific anti-CMV IgM response.

  11. Markedly impaired humoral immune response in mice deficient in complement receptors 1 and 2.

    Science.gov (United States)

    Molina, H; Holers, V M; Li, B; Fung, Y; Mariathasan, S; Goellner, J; Strauss-Schoenberger, J; Karr, R W; Chaplin, D D

    1996-04-16

    Complement receptor 1 (CR1, CD35) and complement receptor 2 (CR2, CD21) have been implicated as regulators of B-cell activation. We explored the role of these receptors in the development of humoral immunity by generating CR1- and CR2-deficient mice using gene-targeting techniques. These mice have normal basal levels of IgM and of IgG isotypes. B- and T-cell development are overtly normal. Nevertheless, B-cell responses to low and high doses of a T-cell-dependent antigen are impaired with decreased titers of antigen-specific IgM and IgG isotypes. This defect is not complete because there is still partial activation of B lymphocytes during the primary immune response, with generation of splenic germinal centers and a detectable, although reduced, secondary antibody response. These data suggest that certain T-dependent antigens manifest an absolute dependence on complement receptors for the initiation of a normally robust immune response.

  12. Cellular Immune Responses in Humans Induced by Two Serogroup B Meningococcal Outer Membrane Vesicle Vaccines Given Separately and in Combination.

    Science.gov (United States)

    Oftung, Fredrik; Korsvold, Gro Ellen; Aase, Audun; Næss, Lisbeth M

    2016-04-01

    MenBvac and MeNZB are safe and efficacious outer membrane vesicle (OMV) vaccines against serogroup B meningococcal disease. Antibody responses have previously been investigated in a clinical trial with these two OMV vaccines given separately (25 μg/dose) or in combination (12.5 and 12.5 μg/dose) in three doses administered at 6-week intervals. Here, we report the results from analyzing cellular immune responses against MenBvac and MeNZB OMVs in terms of antigen-specific CD4(+)T cell proliferation and secretion of cytokines. The proliferative CD4(+)T cell responses to the combined vaccine were of the same magnitude as the homologous responses observed for each individual vaccine. The results also showed cross-reactivity in the sense that both vaccine groups receiving separate vaccines responded to both homologous and heterologous OMV antigen when assayed for antigen-specific cellular proliferation. In addition, a multiplex bead array assay was used to analyze the presence of Th1 and Th2 cytokines in cell culture supernatants. The results showed that gamma interferon, interleukin-4 (IL-4), and IL-10 responses could be detected as a result of vaccination with both the MenBvac and the MeNZB vaccines given separately, as well as when given in combination. With respect to cross-reactivity, the cytokine results paralleled the observations made for proliferation. In conclusion, the results demonstrate that cross-reactive cellular immune responses involving both Th1 and Th2 cytokines can be induced to the same extent by different tailor-made OMV vaccines given either separately or in combination with half the dose of each vaccine. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  13. The nitric oxide redox sibling nitroxyl partially circumvents impairment of platelet nitric oxide responsiveness.

    Science.gov (United States)

    Dautov, R F; Ngo, D T M; Licari, G; Liu, S; Sverdlov, A L; Ritchie, R H; Kemp-Harper, B K; Horowitz, J D; Chirkov, Y Y

    2013-11-30

    Impaired platelet responsiveness to nitric oxide (NO resistance) is a common characteristic of many cardiovascular disease states and represents an independent risk factor for cardiac events and mortality. NO resistance reflects both scavenging of NO by superoxide (O2(-)), and impairment of the NO receptor, soluble guanylate cyclase (sGC). There is thus an urgent need for circumvention of NO resistance in order to improve clinical outcomes. Nitroxyl (HNO), like NO, produces vasodilator and anti-aggregatory effects, largely via sGC activation, but is not inactivated by O2(-). We tested the hypothesis that HNO circumvents NO resistance in human platelets. In 57 subjects with or without ischemic heart disease, platelet responses to the HNO donor isopropylamine NONOate (IPA/NO) and the NO donor sodium nitroprusside (SNP) were compared. While SNP (10μM) induced 29±3% (p<0.001) inhibition of platelet aggregation, IPA/NO (10μM) caused 75±4% inhibition (p<0.001). In NO-resistant subjects (n=28), the IPA/NO:SNP response ratio was markedly increased (p<0.01), consistent with partial circumvention of NO resistance. Similarly, cGMP accumulation in platelets was greater (p<0.001) with IPA/NO than with SNP stimulation. The NO scavenger carboxy-PTIO (CPTIO, 200μM) inhibited SNP and IPA/NO responses by 92±7% and 17±4% respectively (p<0.001 for differential inhibition), suggesting that effects of IPA/NO are only partially NO-mediated. ODQ (10μM) inhibited IPA/NO responses by 36±8% (p<0.001), consistent with a contribution of sGC/haem to IPA/NO inhibition of aggregation. There was no significant relationship between whole blood ROS content and IPA/NO responses. Thus the HNO donor IPA/NO substantially circumvents platelet NO resistance while acting, at least partially, as a haem-mediated sGC activator.

  14. Changes in Stoichiometry, Cellular RNA, and Alkaline Phosphatase Activity of Chlamydomonas in Response to Temperature and Nutrients.

    Science.gov (United States)

    Hessen, Dag O; Hafslund, Ola T; Andersen, Tom; Broch, Catharina; Shala, Nita K; Wojewodzic, Marcin W

    2017-01-01

    Phytoplankton may respond both to elevated temperatures and reduced nutrients by changing their cellular stoichiometry and cell sizes. Since increased temperatures often cause increased thermal stratification and reduced vertical flux of nutrients into the mixed zone, it is difficult to disentangle these drivers in nature. In this study, we used a factorial design with high and low levels of phosphorus (P) and high and low temperature to assess responses in cellular stoichiometry, levels of RNA, and alkaline phosphatase activity (APA) in the chlorophyte Chlamydomonas reinhardtii. Growth rate, C:P, C:N, N:P, RNA, and APA all responded primarily to P treatment, but except for N:P and APA, also temperature contributed significantly. For RNA, the contribution from temperature was particularly strong with higher cellular levels of RNA at low temperatures, suggesting a compensatory allocation to ribosomes to maintain protein synthesis and growth. These experiments suggest that although P-limitation is the major determinant of growth rate and cellular stoichiometry, there are pronounced effects of temperature also via interaction with P. At the ecosystem level, nutrients and temperature will thus interact, but temperatures would likely exert a stronger impact on these phytoplankton traits indirectly via its force on stratification regimes and vertical nutrient fluxes.

  15. Changes in Stoichiometry, Cellular RNA, and Alkaline Phosphatase Activity of Chlamydomonas in Response to Temperature and Nutrients

    Science.gov (United States)

    Hessen, Dag O.; Hafslund, Ola T.; Andersen, Tom; Broch, Catharina; Shala, Nita K.; Wojewodzic, Marcin W.

    2017-01-01

    Phytoplankton may respond both to elevated temperatures and reduced nutrients by changing their cellular stoichiometry and cell sizes. Since increased temperatures often cause increased thermal stratification and reduced vertical flux of nutrients into the mixed zone, it is difficult to disentangle these drivers in nature. In this study, we used a factorial design with high and low levels of phosphorus (P) and high and low temperature to assess responses in cellular stoichiometry, levels of RNA, and alkaline phosphatase activity (APA) in the chlorophyte Chlamydomonas reinhardtii. Growth rate, C:P, C:N, N:P, RNA, and APA all responded primarily to P treatment, but except for N:P and APA, also temperature contributed significantly. For RNA, the contribution from temperature was particularly strong with higher cellular levels of RNA at low temperatures, suggesting a compensatory allocation to ribosomes to maintain protein synthesis and growth. These experiments suggest that although P-limitation is the major determinant of growth rate and cellular stoichiometry, there are pronounced effects of temperature also via interaction with P. At the ecosystem level, nutrients and temperature will thus interact, but temperatures would likely exert a stronger impact on these phytoplankton traits indirectly via its force on stratification regimes and vertical nutrient fluxes. PMID:28167934

  16. Proteomic analysis of cellular response induced by multi-walled carbon nanotubes exposure in A549 cells.

    Directory of Open Access Journals (Sweden)

    Li Ju

    Full Text Available The wide application of multi-walled carbon nanotubes (MWCNT has raised serious concerns about their safety on human health and the environment. However, the potential harmful effects of MWCNT remain unclear and contradictory. To clarify the potentially toxic effects of MWCNT and to elucidate the associated underlying mechanisms, the effects of MWCNT on human lung adenocarcinoma A549 cells were examined at both the cellular and the protein level. Cytotoxicity and genotoxicity were examined, followed by a proteomic analysis (2-DE coupled with LC-MS/MS of the cellular response to MWCNT. Our results demonstrate that MWCNT induces cytotoxicity in A549 cells only at relatively high concentrations and longer exposure time. Within a relatively low dosage range (30 µg/ml and short time period (24 h, MWCNT treatment does not induce significant cytotoxicity, cell cycle changes, apoptosis, or DNA damage. However, at these low doses and times, MWCNT treatment causes significant changes in protein expression. A total of 106 proteins show altered expression at various time points and dosages, and of these, 52 proteins were further identified by MS. Identified proteins are involved in several cellular processes including proliferation, stress, and cellular skeleton organization. In particular, MWCNT treatment causes increases in actin expression. This increase has the potential to contribute to increased migration capacity and may be mediated by reactive oxygen species (ROS.

  17. Acidic mist reduces foliar membrane-associated calcium and impairs stomatal responsiveness in red spruce

    Energy Technology Data Exchange (ETDEWEB)

    Borer, C. H.; DeHayes, D. H. [University of Vermont, Rubinstein School of Environment and Natural Resources, Burlington, VT (United States); Schaberg, P. G. [USDA Forest Service, Northeastern Research Station, South Burlington, VT (United States)

    2005-06-01

    The possibility of impairment of stomatal responsiveness due to acidic mist-induced depletion of foliar membrane calcium (mCa) was investigated by exposing red spruce seedlings to either pH 3.0 or pH 5.0 mist treatments for one growing season. Foliar nutrition was assessed following each treatment, and declines in stomatal conductance and net photosynthesis were measured on current year shoots following stem excision. Seedlings subjected to pH 3.0 acidic mist treatment had reduced mCa, and exhibited impaired stomatal function, including a smaller maximum aperture, slower closure, increased lag time between stomatal closure and photosynthetic decline following experimental water stress, relative to seedling treated with pH 5.0 acidic mist. The evidence supports the hypothesis that anthropogenetically caused depletion of mCa may disrupt physiological processes that depend on foliar Ca, in the process reducing the plants ability to respond adaptively to environmental stresses. 69 refs., 1 tab., 1 fig.

  18. p130Cas over-expression impairs mammary branching morphogenesis in response to estrogen and EGF.

    Directory of Open Access Journals (Sweden)

    Maria del Pilar Camacho Leal

    Full Text Available p130Cas adaptor protein regulates basic processes such as cell cycle control, survival and migration. p130Cas over-expression has been related to mammary gland transformation, however the in vivo consequences of p130Cas over-expression during mammary gland morphogenesis are not known. In ex vivo mammary explants from MMTV-p130Cas transgenic mice, we show that p130Cas impairs the functional interplay between Epidermal Growth Factor Receptor (EGFR and Estrogen Receptor (ER during mammary gland development. Indeed, we demonstrate that p130Cas over-expression upon the concomitant stimulation with EGF and estrogen (E2 severely impairs mammary morphogenesis giving rise to enlarged multicellular spherical structures with altered architecture and absence of the central lumen. These filled acinar structures are characterized by increased cell survival and proliferation and by a strong activation of Erk1/2 MAPKs and Akt. Interestingly, antagonizing the ER activity is sufficient to re-establish branching morphogenesis and normal Erk1/2 MAPK activity. Overall, these results indicate that high levels of p130Cas expression profoundly affect mammary morphogenesis by altering epithelial architecture, survival and unbalancing Erk1/2 MAPKs activation in response to growth factors and hormones. These results suggest that alteration of morphogenetic pathways due to p130Cas over-expression might prime mammary epithelium to tumorigenesis.

  19. Characterization of Cellular and Humoral Immune Responses After IBV Infection in Chicken Lines Differing in MBL Serum Concentration

    DEFF Research Database (Denmark)

    Kjærup, Rikke Munkholm; Dalgaard, Tina Sørensen; Norup, Liselotte Rothmann

    2014-01-01

    Chickens from two inbred lines selected for high (L10H) or low (L10L) mannose-binding lectin (MBL) serum concentrations were infected with infectious bronchitis virus (IBV), and innate as well as adaptive immunological parameters were measured throughout the experimental period. Chickens with high...... L10H chickens than in the infected and noninfected L10L chickens. Thus, these results indicate that MBL is produced locally and may be involved in the regulation of the cellular immune response after an IBV infection. However, MBL did not appear to influence the humoral immune response after IBV...

  20. Cellular biomarker responses of limpets (Mollusca as measure of sensitivity to cadmiumcontamination

    Directory of Open Access Journals (Sweden)

    Koot Reinecke

    2008-09-01

    Full Text Available Due to the availability and chemical nature of some heavy metals, sub-lethal toxicant levels may persist in the ocean waters and may cause physiological problems and toxicity in invertebrates and other marine organisms. Although studies of metal concentrations in False Bay showed relatively low mean concentrations of Cd, invertebrates such as molluscs, crustaceans and many other groups are able to accumulate high levels of heavy metals in their tissues and still survive in the heaviest polluted areas. They can accumulate numerous pollutants from natural waters in quantities that are many orders of magnitude higher than background levels. Bioaccumulation ofcadmium in intertidal species could cause stress which may be measurable at the cellular level. A variety of limpet species that may serve as suitable ecotoxicological monitoring species occur in abundance on rocky shores along the South African coastline. The aim of this study was to obtain sensitivity data which could contribute to the selection of a suitable monitoring species and the eventual establishment of a species sensitivity distribution model (SSD with a biomarker responseas endpoint. The limpets Cymbula oculus, Scutellastra longicosta, Cymbula granatina and Scutellastragranularis as well as water samples were collected at two localities in False Bay, South Africa. Analysis of water and biological samples were done by atomic absorption spectrometry. Exposures were done to three different sublethal concentrations of cadmium in the laboratory in static flow tanks over three days. There was a moderate increase in cadmium body concentrations over time. Results obtained at three exposure concentrations showed no significant differences in metal concentrations between the different C. oculus samples. Significant differences were obtained between the control and the exposure groups for each exposure time except between the control and the 1mg/L CdCl2 exposure group after 24 and 72 hours of

  1. Physiological cardiac remodelling in response to endurance exercise training: cellular and molecular mechanisms.

    Science.gov (United States)

    Ellison, Georgina M; Waring, Cheryl D; Vicinanza, Carla; Torella, Daniele

    2012-01-01

    Exercise training fosters the health and performance of the cardiovascular system, and represents nowadays a powerful tool for cardiovascular therapy. Exercise exerts its beneficial effects through reducing cardiovascular risk factors, and directly affecting the cellular and molecular remodelling of the heart. Traditionally, moderate endurance exercise training has been viewed to determine a balanced and revertible physiological growth, through cardiomyocyte hypertrophy accompanied by appropriate neoangiogenesis (the Athlete's Heart). These cellular adaptations are due to the activation of signalling pathways and in particular, the IGF-1/IGF-1R/Akt axis appears to have a major role. Recently, it has been shown that physical exercise determines cardiac growth also through new cardiomyocyte formation. Accordingly, burgeoning evidence indicates that exercise training activates circulating, as well as resident tissue-specific cardiac, stem/progenitor cells. Dissecting the mechanisms for stem/progenitor cell activation with exercise will be instrumental to devise new effective therapies, encompassing myocardial regeneration for a large spectrum of cardiovascular diseases.

  2. Interaction of cellular-localized signature modules in response to prostate cancer

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Rapid progress in high-throughput biotechnologies (e. g. microarrays) and exponential accumulation of gene functional knowledge makes it promising for systematic understanding of complex human diseases at the functional modules level. Current modular categorizations can be defined and selected more specifically and precisely in terms of both biological processes and cellular locations, aiming at uncovering the modular molecular networks highly relevant to cancers. Based on Gene Ontology, we identifed the functional modules enriched with differentially expressed genes and characterized by biological processes and specific cellular locations. Then, according to the ranking of the disease discriminating abilities of the pre-selected functional modules, we further defined and filtered signature modules which have higher relevance to the cancer under study. Applications of the proposed method to the analysis of a prostate cancer dataset revealed insightful biological modules.

  3. Discovering the cellular-localized functional modules and modular interactions in response to liver cancer

    Institute of Scientific and Technical Information of China (English)

    Zhu Jing; Guo Zheng; Yang Da; Zhang Min; Wang Jing; Wang Chenguang

    2008-01-01

    In this paper, we firstly identify the functional modules enriched with differentially expressed genes (DEGs) and characterized by biological processes in specific cellular locations, based on gene ontology (GO) and microarray data. Then, we further define and filter disease relevant signature modules according to the ranking of the disease discriminating abilities of the pre-selected functional modules. At last, we analyze the potential way by which they cooperate towards human disease. Application of the proposed method to the analysis of a liver cancer dataset shows that, using the same false discovery rate (FDR) threshold, we can find more biologically meaningful and detailed processes by using the cellular localization information. Some biological evidences support the relevancy of our biological modules to the disease mechanism.

  4. High cortisol awakening response is associated with an impairment of the effect of bright light therapy

    DEFF Research Database (Denmark)

    Martiny, Klaus Per Juul; Lunde, Marianne Anita; Undén, M;

    2009-01-01

    OBJECTIVE: We investigated the predictive validity of the cortisol awakening response (CAR) in patients with non-seasonal major depression. METHOD: Patients were treated with sertraline in combination with bright or dim light therapy for a 5-week period. Saliva cortisol levels were measured in 63...... patients, as an awakening profile, before medication and light therapy started. The CAR was calculated by using three time-points: awakening and 20 and 60 min after awakening. RESULTS: Patients with low CAR had a very substantial effect of bright light therapy compared with dim light therapy, whereas...... patients with a high CAR had no effect of bright light therapy compared with dim light therapy. CONCLUSION: High CAR was associated with an impairment of the effect of bright light therapy. This result raises the question of whether bright light acts through a mechanism different from...

  5. Responsiveness of the Multiple Sclerosis Impairment Scale in comparison with the Expanded Disability Status Scale

    DEFF Research Database (Denmark)

    Ravnborg, M; Blinkenberg, M; Sellebjerg, F

    2005-01-01

    The Multiple Sclerosis Impairment Scale (MSIS) is a measure of accumulated deficits assessed by means of a standard neurological examination. We compared the responsiveness of the MSIS with that of the Expanded Disability Status Scale (EDSS). We reviewed 4300 records collected systematically from...... 1995 to 2003 and identified 534 patients who had clinically definite multiple sclerosis and had had at least two clinical assessments with a time interval of 2-5 years. The rate of deterioration was significantly higher on the MSIS than on the EDSS. The annualized change in EDSS exhibited a maximum...... at baseline EDSS 4 and a subsequent rapid decline at higher baseline EDSS, while the annualized change in MSIS was fairly stable over a wide middle range of baseline MSIS. The variance of the annualized change in EDSS fluctuated markedly between the baseline EDSS categories, being highest at baseline EDSS 2...

  6. Analysis of the cellular stress response in MCF10A cells exposed to combined radio frequency radiation.

    Science.gov (United States)

    Kim, Han-Na; Han, Na-Kyung; Hong, Mi-Na; Chi, Sung-Gil; Lee, Yun-Sil; Kim, Taehong; Pack, Jeong-Ki; Choi, Hyung-Do; Kim, Nam; Lee, Jae-Seon

    2012-01-01

    Exposure to environmental stressors can be measured by monitoring the cellular stress response in target cells. Here, we used the cellular stress response to investigate whether single or combined radio frequency (RF) radiation could induce stress response in human cells. Cellular stress responses in MCF10A human breast epithelial cells were characterized after exposure to 4 h of RF radiation [code division multiple access (CDMA) or CDMA plus wideband CDMA (WCDMA)] or 2 h RF radiation on 3 consecutive days. Specific absorption rate (SAR) was 4.0 W/kg for CDMA signal alone exposure and 2.0 W/kg each, 4.0 W/kg in total for combined CDMA plus WCDMA signals. Expression levels and phosphorylation states of specific heat shock proteins (HSPs) and mitogen-activated protein kinases (MAPKs) were analyzed by Western blot. It was found that HSP27 and ERK1/2 phosphorylations are the most sensitive markers of the stress response in MCF10A cells exposed to heat shock or ionizing radiation. Using these markers, we demonstrated that neither one-time nor repeated single (CDMA alone) or combined (CDMA plus WCDMA) RF radiation exposure significantly altered HSP27 and ERK1/2 phosphorylations in MCF10A cells (p > 0.05). The lack of a statistically significant alteration in HSP27 and ERK1/2 phosphorylations suggests that single or combined RF radiation exposure did not elicit activation of HSP27 and ERK1/2 in MCF10A cells.

  7. Cellular Homeostasis and Antioxidant Response in Epithelial HT29 Cells on Titania Nanotube Arrays Surface

    Directory of Open Access Journals (Sweden)

    Rabiatul Basria SMN Mydin

    2017-01-01

    Full Text Available Cell growth and proliferative activities on titania nanotube arrays (TNA have raised alerts on genotoxicity risk. Present toxicogenomic approach focused on epithelial HT29 cells with TNA surface. Fledgling cell-TNA interaction has triggered G0/G1 cell cycle arrests and initiates DNA damage surveillance checkpoint, which possibly indicated the cellular stress stimuli. A profound gene regulation was observed to be involved in cellular growth and survival signals such as p53 and AKT expressions. Interestingly, the activation of redox regulator pathways (antioxidant defense was observed through the cascade interactions of GADD45, MYC, CHECK1, and ATR genes. These mechanisms furnish to protect DNA during cellular division from an oxidative challenge, set in motion with XRRC5 and RAD50 genes for DNA damage and repair activities. The cell fate decision on TNA-nanoenvironment has been reported to possibly regulate proliferative activities via expression of p27 and BCL2 tumor suppressor proteins, cogent with SKP2 and BCL2 oncogenic proteins suppression. Findings suggested that epithelial HT29 cells on the surface of TNA may have a positive regulation via cell-homeostasis mechanisms: a careful circadian orchestration between cell proliferation, survival, and death. This nanomolecular knowledge could be beneficial for advanced medical applications such as in nanomedicine and nanotherapeutics.

  8. Loss of transcription factor early growth response gene 1 results in impaired endochondral bone repair.

    Science.gov (United States)

    Reumann, Marie K; Strachna, Olga; Yagerman, Sarah; Torrecilla, Daniel; Kim, Jihye; Doty, Stephen B; Lukashova, Lyudmila; Boskey, Adele L; Mayer-Kuckuk, Philipp

    2011-10-01

    Transcription factors that play a role in ossification during development are expected to participate in postnatal fracture repair since the endochondral bone formation that occurs in embryos is recapitulated during fracture repair. However, inherent differences exist between bone development and fracture repair, including a sudden disruption of tissue integrity followed by an inflammatory response. This raises the possibility that repair-specific transcription factors participate in bone healing. Here, we assessed the consequence of loss of early growth response gene 1 (EGR-1) on endochondral bone healing because this transcription factor has been shown to modulate repair in vascularized tissues. Model fractures were created in ribs of wild type (wt) and EGR-1(-/-) mice. Differences in tissue morphology and composition between these two animal groups were followed over 28 post fracture days (PFDs). In wt mice, bone healing occurred in healing phases characteristic of endochondral bone repair. A similar healing sequence was observed in EGR-1(-/-) mice but was impaired by alterations. A persistent accumulation of fibrin between the disconnected bones was observed on PFD7 and remained pronounced in the callus on PFD14. Additionally, the PFD14 callus was abnormally enlarged and showed increased deposition of mineralized tissue. Cartilage ossification in the callus was associated with hyper-vascularity and -proliferation. Moreover, cell deposits located in proximity to the callus within skeletal muscle were detected on PFD14. Despite these impairments, repair in EGR-1(-/-) callus advanced on PFD28, suggesting EGR-1 is not essential for healing. Together, this study provides genetic evidence that EGR-1 is a pleiotropic regulator of endochondral fracture repair. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Cleavage of serum response factor mediated by enteroviral protease 2A contributes to impaired cardiac function

    Institute of Scientific and Technical Information of China (English)

    Jerry Wong; Jingchun Zhang; Bobby Yanagawa; Zongshu Luo; Xiangsheng Yang; Jiang Chang; Bruce McManus; Honglin Luo

    2012-01-01

    Enteroviral infection can lead to dilated cardiomyopathy (DCM),which is a major cause of cardiovascular mortality worldwide.However,the pathogenetic mechanisms have not been fully elucidated.Serum response factor (SRF) is a cardiac-enriched transcription regulator controlling the expression of a variety of target genes,including those involved in the contractile apparatus and immediate early response,as well as microRNAs that silence the expression of cardiac regulatory factors.Knockout of SRF in the heart results in downregulation of cardiac contractile gene expression and development of DCM.The goal of this study is to understand the role of SRF in enterovirus-induced cardiac dysfunction and progression to DCM.Here we report that SRF is cleaved following enteroviral infection of mouse heart and cultured cardiomyocytes.This cleavage is accompanied by impaired cardiac function and downregulation of cardiac-specific contractile and regulatory genes.Further investigation by antibody epitope mapping and site-directed mutagenesis demonstrates that SRF cleavage occurs at the region of its transactivation domain through the action of virus-encoded protease 2A.Moreover,we demonstrate that cleavage of SRF dissociates its transactivation domain from DNA-binding domain,resulting in the disruption of SRF-mediated gene transactivation.In addition to loss of functional SRF,finally we report that the N-terminal fragment of SRF cleavage products can also act as a dominant-negative transcription factor,which likely competes with the native SRF for DNA binding.Our results suggest a mechanism by which virus infection impairs heart function and may offer a new therapeutic strategy to ameliorate myocardial damage and progression to DCM.

  10. Adipose-Derived Mesenchymal Stem Cells Restore Impaired Mucosal Immune Responses in Aged Mice.

    Directory of Open Access Journals (Sweden)

    Kazuyoshi Aso

    Full Text Available It has been shown that adipose-derived mesenchymal stem cells (AMSCs can differentiate into adipocytes, chondrocytes and osteoblasts. Several clinical trials have shown the ability of AMSCs to regenerate these differentiated cell types. Age-associated dysregulation of the gastrointestinal (GI immune system has been well documented. Our previous studies showed that impaired mucosal immunity in the GI tract occurs earlier during agingthan is seen in the systemic compartment. In this study, we examined the potential of AMSCs to restore the GI mucosal immune system in aged mice. Aged (>18 mo old mice were adoptively transferred with AMSCs. Two weeks later, mice were orally immunized with ovalbumin (OVA plus cholera toxin (CT three times at weekly intervals. Seven days after the final immunization, when fecal extract samples and plasma were subjected to OVA- and CT-B-specific ELISA, elevated levels of mucosal secretory IgA (SIgA and plasma IgG antibody (Ab responses were noted in aged mouse recipients. Similar results were also seen aged mice which received AMSCs at one year of age. When cytokine production was examined, OVA-stimulated Peyer's patch CD4+ T cells produced increased levels of IL-4. Further, CD4+ T cells from the lamina propria revealed elevated levels of IL-4 and IFN-γ production. In contrast, aged mice without AMSC transfer showed essentially no OVA- or CT-B-specific mucosal SIgA or plasma IgG Ab or cytokine responses. Of importance, fecal extracts from AMSC transferred aged mice showed neutralization activity to CT intoxication. These results suggest that AMSCs can restore impaired mucosal immunity in the GI tract of aged mice.

  11. Receptor interacting protein kinase-2 inhibition by CYLD impairs anti-bacterial immune responses in macrophages

    Directory of Open Access Journals (Sweden)

    Katharina eWex

    2016-01-01

    Full Text Available Upon infection with intracellular bacteria, nucleotide oligomerization domain protein 2 (NOD2 recognizes bacterial muramyl dipeptide and binds, subsequently, to receptor-interacting serine/threonine kinase 2 (RIPK2. RIPK2 mediates the activation of immune responses via the nuclear factor-κB (NF-κB and extracellular-signal regulated kinase (ERK pathways. Previously, it has been shown that RIPK2 activation dependens on its K63-ubiquitination by the E3 ligases pellino-3 and ITCH, whereas the deubiquitinating enzyme A20 counter-regulates RIPK2 activity by cleaving K63-polyubiquitin chains from RIPK2. Here, we newly identify the deubiquitinating enzyme CYLD as a new interacting partner and inhibitor of RIPK2. We show that CYLD binds to and removes K63-polyubiquitin chains from RIPK2 in Listeria monocytogenes (Lm infected bone-marrow-derived macrophages (BMDM. CYLD-mediated K63-deubiquitination of RIPK2 resulted in an impaired activation of both NF-κB and ERK1/2 pathways, reduced production of proinflammatory cytokines (IL-6, IL-12, anti-listerial ROS and NO, and, finally, impaired pathogen control. In turn, RIPK2 inhibition by siRNA prevented activation of NF-κB and ERK1/2 and completely abolished the protective effect of CYLD-deficiency with respect to the production of IL-6, NO, ROS and pathogen control. Noteworthy, CYLD also inhibited autophagy of Listeria in a RIPK2-ERK1/2 dependent manner.The protective function of CYLD-deficiency was dependent on IFN-γ pre-stimulation of infected macrophages. Interestingly, the reduced NF-κB activation in CYLD-expressing macrophages limited the protective effect of IFN-γ by reducing NF-κB-dependent STAT1 activation. Taken together, our study identifies CYLD as an important inhibitor of RIPK2-dependent anti-bacterial immune responses in macrophages.

  12. Response of cellular stoichiometry and phosphorus storage of the cyanobacteria Aphanizomenon flos-aquae to small-scale turbulence

    Science.gov (United States)

    Li, Zhe; Xiao, Yan; Yang, Jixiang; Li, Chao; Gao, Xia; Guo, Jinsong

    2017-01-01

    Turbulent mixing, in particular on a small scale, affects the growth of microalgae by changing diffusive sublayers and regulating nutrient fluxes of cells. We tested the nutrient flux hypothesis by evaluating the cellular stoichiometry and phosphorus storage of microalgae under different turbulent mixing conditions. Aphanizomenon flos-aquae were cultivated in different stirring batch reactors with turbulent dissipation rates ranging from 0.001 51 m2/s3 to 0.050 58 m2/s3, the latter being the highest range observed in natural aquatic systems. Samples were taken in the exponential growth phase and compared with samples taken when the reactor was completely stagnant. Results indicate that, within a certain range, turbulent mixing stimulates the growth of A. flos-aquae. An inhibitory effect on growth rate was observed at the higher range. Photosynthesis activity, in terms of maximum effective quantum yield of PSII (the ratio of F v/F m) and cellular chlorophyll a, did not change significantly in response to turbulence. However, Chl a/C mass ratio and C/N molar ratio, showed a unimodal response under a gradient of turbulent mixing, similar to growth rate. Moreover, we found that increases in turbulent mixing might stimulate respiration rates, which might lead to the use of polyphosphate for the synthesis of cellular constituents. More research is required to test and verify the hypothesis that turbulent mixing changes the diffusive sublayer, regulating the nutrient flux of cells.

  13. Impaired Early-Response Inhibition in Overweight Females with and without Binge Eating Disorder.

    Directory of Open Access Journals (Sweden)

    Jennifer Svaldi

    Full Text Available Several studies report increased reward sensitivity towards food in overweight individuals. By contrast, data is inconclusive with respect to response inhibition in overweight individuals without binge eating disorder (BED. Hence, the latter was addressed in the present study in a group of overweight/obese females with and without BED and a normal-weight control group without eating disorders.A group of women with BED (n = 29, a group of overweight women without BED (n = 33 and normal-weight females (n = 30 participated in a pictorial priming paradigm, with food items (relevant primes and office utensils (neutral primes and color blobs (neutral primes as stimuli. Increased response priming effects (i.e. priming with switches between stimulus categories were taken as indicators of deficient behavioral inhibition.Priming effects for neutral primes were moderate and comparable across all groups. However, primes associated with the food task set lead to increased priming effects in both overweight groups. But, effects were comparable for overweight/obese participants with and without BED.Results suggest that early response inhibition in the context of food is impaired in overweight individuals compared to normal-weight individuals.

  14. Cell-directed assembly on an integrated nanoelectronic/nanophotonic device for probing cellular responses on the nanoscale.

    Energy Technology Data Exchange (ETDEWEB)

    Brinker, C. Jeffrey; Dunphy, Darren Robert; Ashley, Carlee E. (University of New Mexico, Albuquerque, NM); Fan, Hongyou; Lopez, DeAnna (University of New Mexico, Albuquerque, NM); Simpson, Regina Lynn; Tallant, David Robert; Burckel, David Bruce; Baca, Helen Kennicott (University of New Mexico, Albuquerque, NM); Carnes, Eric C. (University of New Mexico, Albuquerque, NM); Singh, Seema

    2006-01-01

    Our discovery that the introduction of living cells (Saccharomyces cerevisiae) alters dramatically the evaporation driven self-assembly of lipid-silica nanostructures suggested the formation of novel bio/nano interfaces useful for cellular interrogation at the nanoscale. This one year ''out of the box'' LDRD focused on the localization of metallic and semi-conducting nanocrystals at the fluid, lipid-rich interface between S. cerevisiae and the surrounding phospholipid-templated silica nanostructure with the primary goal of creating Surface Enhanced Raman Spectroscopy (SERS)-active nanostructures and platforms for cellular integration into electrode arrays. Such structures are of interest for probing cellular responses to the onset of disease, understanding of cell-cell communication, and the development of cell-based bio-sensors. As SERS is known to be sensitive to the size and shape of metallic (principally gold and silver) nanocrystals, various sizes and shapes of nanocrystals were synthesized, functionalized and localized at the cellular surface by our ''cell-directed assembly'' approach. Laser scanning confocal microscopy, SEM, and in situ grazing incidence small angle x-ray scattering (GISAXS) experiments were performed to study metallic nanocrystal localization. Preliminary Raman spectroscopy studies were conducted to test for SERS activity. Interferometric lithography was used to construct high aspect ratio cylindrical holes on patterned gold substrates and electro-deposition experiments were performed in a preliminary attempt to create electrode arrays. A new printing procedure was also developed for cellular integration into nanostructured platforms that avoids solvent exposure and may mitigate osmotic stress. Using a different approach, substrates comprised of self-assembled nanoparticles in a phospholipid templated silica film were also developed. When printed on top of these substrates, the cells integrate

  15. Brain 5-HT deficiency increases stress vulnerability and impairs antidepressant responses following psychosocial stress.

    Science.gov (United States)

    Sachs, Benjamin D; Ni, Jason R; Caron, Marc G

    2015-02-24

    Brain serotonin (5-HT) deficiency and exposure to psychosocial stress have both been implicated in the etiology of depression and anxiety disorders, but whether 5-HT deficiency influences susceptibility to depression- and anxiety-like phenotypes induced by psychosocial stress has not been formally established. Most clinically effective antidepressants increase the extracellular levels of 5-HT, and thus it has been hypothesized that antidepressant responses result from the reversal of endogenous 5-HT deficiency, but this hypothesis remains highly controversial. Here we evaluated the impact of brain 5-HT deficiency on stress susceptibility and antidepressant-like responses using tryptophan hydroxylase 2 knockin (Tph2KI) mice, which display 60-80% reductions in brain 5-HT. Our results demonstrate that 5-HT deficiency leads to increased susceptibility to social defeat stress (SDS), a model of psychosocial stress, and prevents the fluoxetine (FLX)-induced reversal of SDS-induced social avoidance, suggesting that 5-HT deficiency may impair antidepressant responses. In light of recent clinical and preclinical studies highlighting the potential of inhibiting the lateral habenula (LHb) to achieve antidepressant and antidepressant-like responses, we also examined whether LHb inhibition could achieve antidepressant-like responses in FLX-insensitive Tph2KI mice subjected to SDS. Our data reveal that using designer receptors exclusively activated by designer drugs (DREADDs) to inhibit LHb activity leads to reduced SDS-induced social avoidance behavior in both WT and Tph2KI mice. This observation provides additional preclinical evidence that inhibiting the LHb might represent a promising alternative therapeutic approach under conditions in which selective 5-HT reuptake inhibitors are ineffective.

  16. Response of C2C12 myoblasts to hypoxia: the relative roles of glucose and oxygen in adaptive cellular metabolism.

    Science.gov (United States)

    Li, Wei; Hu, Zhen-Fu; Chen, Bin; Ni, Guo-Xin

    2013-01-01

    Oxygen and glucose are two important nutrients for mammalian cell function. In this study, the effect of glucose and oxygen concentrations on C2C12 cellular metabolism was characterized with an emphasis on detecting whether cells show oxygen conformance (OC) in response to hypoxia. After C2C12 cells being cultured in the levels of glucose at 0.6 mM (LG), 5.6 mM (MG), or 23.3 mM(HG) under normoxic or hypoxic (1% oxygen) condition, cellular oxygen consumption, glucose consumption, lactate production, and metabolic status were determined. Short-term oxygen consumption was measured with a novel oxygen biosensor technique. Longer-term measurements were performed with standard glucose, lactate, and cell metabolism assays. It was found that oxygen depletion in normoxia is dependent on the glucose concentration in the medium. Cellular glucose uptake and lactate production increased significantly in hypoxia than those in normoxia. In hypoxia the cellular response to the level of glucose was different to that in normoxia. The metabolic activities decreased while glucose concentration increased in normoxia, while in hypoxia, metabolic activity was reduced in LG and MG, but unchanged in HG condition. The OC phenomenon was not observed in the present study. Our findings suggested that a combination of low oxygen and low glucose damages the viability of C2C12 cells more seriously than low oxygen alone. In addition, when there is sufficient glucose, C2C12 cells will respond to hypoxia by upregulating anaerobic respiration, as shown by lactate production.

  17. Characterisation of the p53-mediated cellular responses evoked in primary mouse cells following exposure to ultraviolet radiation.

    Directory of Open Access Journals (Sweden)

    Gillian D McFeat

    Full Text Available Exposure to ultraviolet (UV light can cause significant damage to mammalian cells and, although the spectrum of damage produced varies with the wavelength of UV, all parts of the UV spectrum are recognised as being detrimental to human health. Characterising the cellular response to different wavelengths of UV therefore remains an important aim so that risks and their moderation can be evaluated, in particular in relation to the initiation of skin cancer. The p53 tumour suppressor protein is central to the cellular response that protects the genome from damage by external agents such as UV, thus reducing the risk of tumorigenesis. In response to a variety of DNA damaging agents including UV light, wild-type p53 plays a role in mediating cell-cycle arrest, facilitating apoptosis and stimulating repair processes, all of which prevent the propagation of potentially mutagenic defects. In this study we examined the induction of p53 protein and its influence on the survival of primary mouse fibroblasts exposed to different wavelengths of UV light. UVC was found to elevate p53 protein and its sequence specific DNA binding capacity. Unexpectedly, UVA treatment failed to induce p53 protein accumulation or sequence specific DNA binding. Despite this, UVA exposure of wild-type cells induced a p53 dependent G1 cell cycle arrest followed by a wave of p53 dependent apoptosis, peaking 12 hours post-insult. Thus, it is demonstrated that the elements of the p53 cellular response evoked by exposure to UV radiation are wavelength dependent. Furthermore, the interrelationship between various endpoints is complex and not easily predictable. This has important implications not only for understanding the mode of action of p53 but also for the use of molecular endpoints in quantifying exposure to different wavelengths of UV in the context of human health protection.

  18. Synergistic and additive effects of cimetidine and levamisole on cellular immune responses to hepatitis B virus DNA vaccine in mice.

    Science.gov (United States)

    Niu, X; Yang, Y; Wang, J

    2013-02-01

    We and others have previously shown that both cimetidine (CIM) and levamisole (LMS) enhance humoral and cellular responses to DNA vaccines via different mechanisms. In this study, we investigated the synergistic and additive effects of CIM and LMS on the potency of antigen-specific immunities generated by a DNA vaccine encoding the hepatitis B surface antigen (HBsAg, pVax-S2). Compared with CIM or LMS alone, the combination of CIM and LMS elicited a robust HBsAg-specific cellular response that was characterized by higher IgG2a, but did not further increase HBsAg-specific antibody IgG and IgG1 production. Consistent with these results, the combination of CIM and LMS produced the highest level of IL-2 and IFN-γ in antigen-specific CD4(+) T cells, whereas the combination of CIM and LMS did not further increase IL-4 production. Significantly, a robust HBsAg-specific cytotoxic response was also observed in the animals immunized with pVax-S2 in the presence of the combination of CIM and LMS. Further mechanistic studies demonstrated that the combination of CIM and LMS promoted dendritic cell (DC) activation and blocked anti-inflammatory cytokine IL-10 and TGF-β production in CD4(+) CD25(+) T cells. These findings suggest that CIM and LMS have the synergistic and additive ability to enhance cellular response to hepatitis B virus DNA vaccine, which may be mediated by DC activation and inhibition of anti-inflammatory cytokine expression. Thus, the combination of cimetidine and levamisole may be useful as an effective adjuvant in DNA vaccinations for chronic hepatitis B virus infection.

  19. Enhanced cellular responses and distinct gene profiles in human fetoplacental artery endothelial cells under chronic low oxygen.

    Science.gov (United States)

    Jiang, Yi-Zhou; Wang, Kai; Li, Yan; Dai, Cai-Feng; Wang, Ping; Kendziorski, Christina; Chen, Dong-Bao; Zheng, Jing

    2013-12-01

    Fetoplacental endothelial cells are exposed to oxygen levels ranging from 2% to 8% in vivo. However, little is known regarding endothelial function within this range of oxygen because most laboratories use ambient air (21% O2) as a standard culture condition (SCN). We asked whether human umbilical artery endothelial cells (HUAECs) that were steadily exposed to the physiological chronic normoxia (PCN, 3% O2) for ∼20-25 days differed in their proliferative and migratory responses to FGF2 and VEGFA as well as in their global gene expression compared with those in the SCN. We observed that PCN enhanced FGF2- and VEGFA-stimulated cell proliferation and migration. In oxygen reversal experiments (i.e., when PCN cells were exposed to SCN for 24 h and vice versa), we found that preexposure to 21% O2 decreased the migratory ability, but not the proliferative ability, of the PCN-HUAECs in response to FGF2 and VEGFA. These PCN-enhanced cellular responses were associated with increased protein levels of HIF1A and NOS3, but not FGFR1, VEGFR1, and VEGFR2. Microarray analysis demonstrated that PCN up-regulated 74 genes and down-regulated 86, 14 of which were directly regulated by hypoxia-inducible factors as evaluated using in silico analysis. Gene function analysis further indicated that the PCN-regulated genes were highly related to cell proliferation and migration, consistent with the results from our functional assays. Given that PCN significantly alters cellular responses to FGF2 and VEGFA as well as transcription in HUAECs, it is likely that we may need to reexamine the current cellular and molecular mechanisms controlling fetoplacental endothelial functions, which were largely derived from endothelial models established under ambient O2.

  20. Cerebral blood flow response to hypoglycemia is altered in patients with type 1 diabetes and impaired awareness of hypoglycemia.

    Science.gov (United States)

    Wiegers, Evita C; Becker, Kirsten M; Rooijackers, Hanne M; von Samson-Himmelstjerna, Federico C; Tack, Cees J; Heerschap, Arend; de Galan, Bastiaan E; van der Graaf, Marinette

    2017-06-01

    It is unclear whether cerebral blood flow responses to hypoglycemia are altered in people with type 1 diabetes and impaired awareness of hypoglycemia. The aim of this study was to investigate the effect of hypoglycemia on both global and regional cerebral blood flow in type 1 diabetes patients with impaired awareness of hypoglycemia, type 1 diabetes patients with normal awareness of hypoglycemia and healthy controls ( n = 7 per group). The subjects underwent a hyperinsulinemic euglycemic-hypoglycemic glucose clamp in a 3 T MR system. Global and regional changes in cerebral blood flow were determined by arterial spin labeling magnetic resonance imaging, at the end of both glycemic phases. Hypoglycemia generated typical symptoms in patients with type 1 diabetes and normal awareness of hypoglycemia and healthy controls, but not in patients with impaired awareness of hypoglycemia. Conversely, hypoglycemia increased global cerebral blood flow in patients with impaired awareness of hypoglycemia, which was not observed in the other two groups. Regionally, hypoglycemia caused a redistribution of cerebral blood flow towards the thalamus of both patients with normal awareness of hypoglycemia and healthy controls, consistent with activation of brain regions associated with the autonomic response to hypoglycemia. No such redistribution was found in the patients with impaired awareness of hypoglycemia. An increase in global cerebral blood flow may enhance nutrient supply to the brain, hence suppressing symptomatic awareness of hypoglycemia. Altogether these results suggest that changes in cerebral blood flow during hypoglycemia contribute to impaired awareness of hypoglycemia.

  1. Specific cellular stimulation in the primary immune response: experimental test of a quantized model.

    OpenAIRE

    Dintzis, R Z; Vogelstein, B; Dintzis, H M

    1982-01-01

    Dose-response and dose-suppression curves have been measured for the primary immune response in mice, in vivo and in vitro, by using size-fractionated linear polymers of acrylamide substituted with hapten. The results are in general agreement with a simple theory based on the premise that the specific primary immunological response is quantized at some fundamental and limiting step, requiring a minimum number of linked antigen receptors for response.

  2. More than just scanning: the importance of cap-independent mRNA translation initiation for cellular stress response and cancer.

    Science.gov (United States)

    Lacerda, Rafaela; Menezes, Juliane; Romão, Luísa

    2017-05-01

    The scanning model for eukaryotic mRNA translation initiation states that the small ribosomal subunit, along with initiation factors, binds at the cap structure at the 5' end of the mRNA and scans the 5' untranslated region (5'UTR) until an initiation codon is found. However, under conditions that impair canonical cap-dependent translation, the synthesis of some proteins is kept by alternative mechanisms that are required for cell survival and stress recovery. Alternative modes of translation initiation include cap- and/or scanning-independent mechanisms of ribosomal recruitment. In most cap-independent translation initiation events there is a direct recruitment of the 40S ribosome into a position upstream, or directly at, the initiation codon via a specific internal ribosome entry site (IRES) element in the 5'UTR. Yet, in some cellular mRNAs, a different translation initiation mechanism that is neither cap- nor IRES-dependent seems to occur through a special RNA structure called cap-independent translational enhancer (CITE). Recent evidence uncovered a distinct mechanism through which mRNAs containing N (6)-methyladenosine (m(6)A) residues in their 5'UTR directly bind eukaryotic initiation factor 3 (eIF3) and the 40S ribosomal subunit in order to initiate translation in the absence of the cap-binding proteins. This review focuses on the important role of cap-independent translation mechanisms in human cells and how these alternative mechanisms can either act individually or cooperate with other cis-acting RNA regulons to orchestrate specific translational responses triggered upon several cellular stress states, and diseases such as cancer. Elucidation of these non-canonical mechanisms reveals the complexity of translational control and points out their potential as prospective novel therapeutic targets.

  3. Heat-shock-induced cellular responses to temperature elevations occurring during orthopaedic cutting

    OpenAIRE

    Dolan, E. B.; Haugh, M. G.; Tallon, D.; Casey, C.; McNamara, L.M.

    2012-01-01

    Severe heat-shock to bone cells caused during orthopaedic procedures can result in thermal damage, leading to cell death and initiating bone resorption. By contrast, mild heat-shock has been proposed to induce bone regeneration. In this study, bone cells are exposed to heat-shock for short durations occurring during surgical cutting. Cellular viability, necrosis and apoptosis are investigated immediately after heat-shock and following recovery of 12, 24 h and 4 days, in osteocyte-like MLO-Y4 ...

  4. Cellular Immune Responses and Viral Diversity in Individuals Treated during Acute and Early HIV-1 Infection

    Science.gov (United States)

    Altfeld, Marcus; Rosenberg, Eric S.; Shankarappa, Raj; Mukherjee, Joia S.; Hecht, Frederick M.; Eldridge, Robert L.; Addo, Marylyn M.; Poon, Samuel H.; Phillips, Mary N.; Robbins, Gregory K.; Sax, Paul E.; Boswell, Steve; Kahn, James O.; Brander, Christian; Goulder, Philip J.R.; Levy, Jay A.; Mullins, James I.; Walker, Bruce D.

    2001-01-01

    Immune responses induced during the early stages of chronic viral infections are thought to influence disease outcome. Using HIV as a model, we examined virus-specific cytotoxic T lymphocytes (CTLs), T helper cells, and viral genetic diversity in relation to duration of infection and subsequent response to antiviral therapy. Individuals with acute HIV-1 infection treated before seroconversion had weaker CTL responses directed at fewer epitopes than persons who were treated after seroconversion. However, treatment-induced control of viremia was associated with the development of strong T helper cell responses in both groups. After 1 yr of antiviral treatment initiated in acute or early infection, all epitope-specific CTL responses persisted despite undetectable viral loads. The breadth and magnitude of CTL responses remained significantly less in treated acute infection than in treated chronic infection, but viral diversity was also significantly less with immediate therapy. We conclude that early treatment of acute HIV infection leads to a more narrowly directed CTL response, stronger T helper cell responses, and a less diverse virus population. Given the need for T helper cells to maintain effective CTL responses and the ability of virus diversification to accommodate immune escape, we hypothesize that early therapy of primary infection may be beneficial despite induction of less robust CTL responses. These data also provide rationale for therapeutic immunization aimed at broadening CTL responses in treated primary HIV infection. PMID:11148221

  5. Gene Expression Profile Changes and Cellular Responses to Bleomycin-Induced DNA Damage in Human Fibroblast Cells in Space

    Science.gov (United States)

    Lu, Tao; Zhang, Ye; Kidane, Yared; Feiveson, Alan; Stodieck, Louis; Karouia, Fathi; Rohde, Larry; Wu, Honglu

    2016-01-01

    Living organisms are constantly exposed to space radiation that consists of energetic protons and other heavier charged particles. In addition, DNA in space can be damaged by toxic chemicals or reactive oxygen species generated due to increased levels of environmental and psychological stresses. Understanding the impact of spaceflight factors, microgravity in particular, on cellular responses to DNA damage affects the accuracy of the radiation risk assessment for astronauts and the mutation rate in microorganisms. Although possible synergistic effects of space radiation and microgravity have been investigated since the early days of the human space program, the published results were mostly conflicting and inconsistent. To investigate the effects of spaceflight on cellular responses to DNA damage, confluent human fibroblast cells (AG1522) flown on the International Space Station (ISS) were treated with bleomycin for three hours in the true microgravity environment, which induced DNA damages including double-strand breaks (DSB). Damages in the DNA were quantified by immunofluorescence staining for ?-H2AX, which showed similar percentages of different types of stained cells between flight and ground. However, there was a slight shift in the distribution of the ?-H2AX foci number in the flown cells with countable foci. Comparison of the cells in confluent and in exponential growth conditions indicated that the proliferation rate between flight and the ground may be responsible for such a shift. A microarray analysis of gene expressions in response to bleomycin treatment was also performed. Comparison of the responsive pathways between the flown and ground cells showed similar responses with the p53 network being the top upstream regulator. Similar responses at the RNA level between different gravity conditions were also observed with a PCR array analysis containing a set of genes involved in DNA damage signaling; with BBC3, CDKN1A, PCNA and PPM1D being significantly

  6. Older Age and Worse Nutritional State Were Related with Impaired Inflammatory Response in Elderly Patients

    Directory of Open Access Journals (Sweden)

    R.A. Tuty Kuswardhani

    2016-07-01

    Full Text Available Background: Ageing process is related with multisystem disorders. One of them is immune response impairment. It is imperative to evaluate the association between age and related nutritional status with inflammatory response in elderly patient. Methods: A cross sectional study to evaluate inflammatory response among elderly patients (≥60 years at Geriatric Out-patient Clinic, Sanglah Hospital was conducted. Seventy-two patients were enrolled in the study. Age, nutritional states (body mass index and mini nutritional assessment, and inflammatory markers (interleukin-2 [IL-2] and C-reactive protein [CRP] and other anthropometric as well as laboratory parameters were measured in the study. Results: In the study it was revealed that age has a moderately negative correlation with both of plasma IL-2 and serum CRP levels (R= -0.305, p=0.009; and R= -0.413, p=0.005, respectively. Plasma IL-2 levels were positively correlated with several variables like body mass index (R=0.282, p=0.016, mini nutritional assessment (R=0.237, p=0.045, biceps skin fold (R=0.291, p=0.013, and triceps skin fold (R=0.258, p=0.028. While serum CRP levels has positive correlation with lying diastolic blood pressure (R=0.345, p=0.020 and negative correlation with calf circumference (R=-0.312, p=0.037. No significant associations were found between diabetes and hypertension with inflammatory markers. Conclusion: This study concluded that older age and worse nutritional state were related to worse inflammatory response in the elderly patients.

  7. Impaired counterregulatory hormonal and metabolic response to exhaustive exercise in obese subjects.

    Science.gov (United States)

    Vettor, R; Macor, C; Rossi, E; Piemonte, G; Federspil, G

    1997-08-01

    A reduction of postprandial thermogenesis has been described in obesity; insulin resistance and/or decreased sympathetic nervous system activity seem to play the major role in its pathogenesis. On the other hand, a normal energy expenditure during exercise has been reported. At present, the response and the role of catecholamines in energy metabolism during exercise in obesity have not been well clarified yet. The aim of this work was to study the metabolic and hormonal changes caused by intense exercise in obesity. Nine obese subjects and ten normal weight controls were submitted to exhaustive exercise on a cycloergometer. Blood glucose, free fatty acids (FFA), glycerol, lactate, beta-OH-butyrate, insulin, glucagon, plasma growth hormone (HGH), catecholamine plasma levels were assayed before and at the end of exercise, and after a recovery period. The energy cost of exercise was evaluated by indirect calorimetry. In our experiment muscular exercise did not provoke any change in blood glucose and FFA plasma levels in either of our groups. In the obese subjects the insulin plasma levels were higher than in the controls. Glucagon plasma levels did not change. The exercise responses of norepinephrine (NE) (4.28 +/- 0.74 vs 8.81 +/- 1.35 nmol/l; P exercise, the thermic effect of exercise did not differ between obese and control subjects (0.335 +/- 0.038 vs 0.425 +/- 0.040 kJ/min x kg fat-free mass. Our findings indicate that an impaired counterregulatory hormone response to exercise exists in obese subjects. The thermic effect of exercise does not seem to be affected by either the reduced catecholamine response nor insulin resistance.

  8. Chronic Stress Impairs Prefrontal Cortex-Dependent Response Inhibition and Spatial Working Memory

    Science.gov (United States)

    Mika, Agnieszka; Mazur, Gabriel J.; Hoffman, Ann N.; Talboom, Joshua S.; Bimonte-Nelson, Heather A.; Sanabria, Federico; Conrad, Cheryl D.

    2012-01-01

    Chronic stress leads to neurochemical and structural alterations in the prefrontal cortex (PFC) that correspond to deficits in PFC-mediated behaviors. The present study examined the effects of chronic restraint stress on response inhibition (using a response-withholding task, fixed-minimum interval schedule of reinforcement, or FMI), and working memory (using a radial arm water maze, RAWM). Adult male Sprague Dawley rats were first trained on the RAWM and subsequently trained on FMI. Following acquisition of FMI, rats were assigned to a restraint stress (6h/d/28d in wire mesh restrainers) or control condition. Immediately after chronic stress, rats were tested on FMI and subsequently on RAWM. FMI results suggest that chronic stress reduces response inhibition capacity and motivation to initiate the task on selective conditions when food reward was not obtained on the preceding trial. RAWM results suggest that chronic stress produces transient deficits in working memory without altering previously consolidated reference memory. Behavioral measures from FMI failed to correlate with metrics from RAWM except for one in which changes in FMI timing precision negatively correlated with changes in RAWM working memory errors for the controls, a finding that was not observed following chronic stress. Fisher’s r to z transformation revealed no significant differences between control and stress with correlation coefficients. These findings are the first to show that chronic stress impairs both response inhibition and working memory, two behaviors that have never been direct compared within the same animals following chronic stress, using FMI, an appetitive task, and RAWM, a non-appetitive task. PMID:22905921

  9. Chronic stress impairs prefrontal cortex-dependent response inhibition and spatial working memory.

    Science.gov (United States)

    Mika, Agnieszka; Mazur, Gabriel J; Hoffman, Ann N; Talboom, Joshua S; Bimonte-Nelson, Heather A; Sanabria, Federico; Conrad, Cheryl D

    2012-10-01

    Chronic stress leads to neurochemical and structural alterations in the prefrontal cortex (PFC) that correspond to deficits in PFC-mediated behaviors. The present study examined the effects of chronic restraint stress on response inhibition (using a response-withholding task, the fixed-minimum interval schedule of reinforcement, or FMI), and working memory (using a radial arm water maze, RAWM). Adult male Sprague-Dawley rats were first trained on the RAWM and subsequently trained on FMI. After acquisition of FMI, rats were assigned to a restraint stress (6h/d/28d in wire mesh restrainers) or control condition. Immediately after chronic stress, rats were tested on FMI and subsequently on RAWM. FMI results suggest that chronic stress reduces response inhibition capacity and motivation to initiate the task on selective conditions when sucrose reward was not obtained on the preceding trial. RAWM results suggest that chronic stress produces transient deficits in working memory without altering previously consolidated reference memory. Behavioral measures from FMI failed to correlate with metrics from RAWM except for one in which changes in FMI timing imprecision negatively correlated with changes in RAWM working memory errors for the controls, a finding that was not observed following chronic stress. Fisher's r-to-z transformation revealed no significant differences between control and stress groups with correlation coefficients. These findings are the first to show that chronic stress impairs both response inhibition and working memory, two behaviors that have never been directly compared within the same animals after chronic stress, using FMI, an appetitive task, and RAWM, a nonappetitive task.

  10. High content analysis at single cell level identifies different cellular responses dependent on nanomaterial concentrations.

    Science.gov (United States)

    Manshian, Bella B; Munck, Sebastian; Agostinis, Patrizia; Himmelreich, Uwe; Soenen, Stefaan J

    2015-09-08

    A mechanistic understanding of nanomaterial (NM) interaction with biological environments is pivotal for the safe transition from basic science to applied nanomedicine. NM exposure results in varying levels of internalized NM in different neighboring cells, due to variances in cell size, cell cycle phase and NM agglomeration. Using high-content analysis, we investigated the cytotoxic effects of fluorescent quantum dots on cultured cells, where all effects were correlated with the concentration of NMs at the single cell level. Upon binning the single cell data into different categories related to NM concentration, this study demonstrates, for the first time, that quantum dots activate both cytoprotective and cytotoxic mechanisms, resulting in a zero net result on the overall cell population, yet with significant effects in cells with higher cellular NM levels. Our results suggest that future NM cytotoxicity studies should correlate NM toxicity with cellular NM numbers on the single cell level, as conflicting mechanisms in particular cell subpopulations are commonly overlooked using classical toxicological methods.

  11. High content analysis at single cell level identifies different cellular responses dependent on nanomaterial concentrations

    Science.gov (United States)

    Manshian, Bella B.; Munck, Sebastian; Agostinis, Patrizia; Himmelreich, Uwe; Soenen, Stefaan J.

    2015-09-01

    A mechanistic understanding of nanomaterial (NM) interaction with biological environments is pivotal for the safe transition from basic science to applied nanomedicine. NM exposure results in varying levels of internalized NM in different neighboring cells, due to variances in cell size, cell cycle phase and NM agglomeration. Using high-content analysis, we investigated the cytotoxic effects of fluorescent quantum dots on cultured cells, where all effects were correlated with the concentration of NMs at the single cell level. Upon binning the single cell data into different categories related to NM concentration, this study demonstrates, for the first time, that quantum dots activate both cytoprotective and cytotoxic mechanisms, resulting in a zero net result on the overall cell population, yet with significant effects in cells with higher cellular NM levels. Our results suggest that future NM cytotoxicity studies should correlate NM toxicity with cellular NM numbers on the single cell level, as conflicting mechanisms in particular cell subpopulations are commonly overlooked using classical toxicological methods.

  12. Evaluation of the Response Bias Scale and Improbable Failure Scale in assessing feigned cognitive impairment.

    Science.gov (United States)

    Grossi, Laura M; Green, Debbie; Einzig, Shanah; Belfi, Brian

    2017-05-01

    The present study evaluated the Response Bias scale (RBS), a symptom validity test embedded within the Minnesota Multiphasic Personality Inventory (MMPI)-2 Restructured Form (MMPI-2-RF) that assesses for feigned neurocognitive complaints, in a sample of pretrial incompetent to stand trial (IST) criminal defendants. Additionally, we examined the Improbable Failure (IF) scale, a performance validity test embedded within the Structured Interview of Reported Symptoms, Second Edition (SIRS-2), which similarly assesses for feigned cognitive impairment (FCI). Results indicated that both the RBS (area under the curve [AUC] = .76) and IF scale (AUC = .72) achieved moderate classification accuracy using the Test of Memory Malingering (TOMM) as the criterion. Further, the RBS and IF scale appeared to be most useful for screening out those defendants who presented as genuine (specificity = 99% and 88%, respectively), and less effective at classifying those defendants suspected of feigning according to the TOMM (sensitivity = 29% and 46%, respectively). In order to identify a significant proportion of IST defendants who may be feigning impairment, considerably lower cutoff scores than those recommended in each measure's manual were evaluated. An RBS T score of 63 (sensitivity = 86%; specificity = 37%), and IF scale raw score of 2 (sensitivity = 80%; specificity = 43%), was required to achieve ≥80% sensitivity; these alternate cutoff scores may therefore be useful when screening inpatient forensic psychiatric IST defendants. Further, the 2 scales effectively predicted TOMM classification in combination, although only the RBS significantly contributed to the model. Implications for the assessment of FCI in forensic psychiatric settings are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  13. Cannabidiol reduces host immune response and prevents cognitive impairments in Wistar rats submitted to pneumococcal meningitis.

    Science.gov (United States)

    Barichello, Tatiana; Ceretta, Renan A; Generoso, Jaqueline S; Moreira, Ana Paula; Simões, Lutiana R; Comim, Clarissa M; Quevedo, João; Vilela, Márcia Carvalho; Zuardi, Antonio Waldo; Crippa, José A; Teixeira, Antônio Lucio

    2012-12-15

    Pneumococcal meningitis is a life-threatening disease characterized by an acute infection affecting the pia matter, arachnoid and subarachnoid space. The intense inflammatory response is associated with a significant mortality rate and neurologic sequelae, such as, seizures, sensory-motor deficits and impairment of learning and memory. The aim of this study was to evaluate the effects of acute and extended administration of cannabidiol on pro-inflammatory cytokines and behavioral parameters in adult Wistar rats submitted to pneumococcal meningitis. Male Wistar rats underwent a cisterna magna tap and received either 10μl of sterile saline as a placebo or an equivalent volume of S. pneumoniae suspension. Rats subjected to meningitis were treated by intraperitoneal injection with cannabidiol (2.5, 5, or 10mg/kg once or daily for 9 days after meningitis induction) or a placebo. Six hours after meningitis induction, the rats that received one dose were killed and the hippocampus and frontal cortex were obtained to assess cytokines/chemokine and brain-derived neurotrophic factor levels. On the 10th day, the rats were submitted to the inhibitory avoidance task. After the task, the animals were killed and samples from the hippocampus and frontal cortex were obtained. The extended administration of cannabidiol at different doses reduced the TNF-α level in frontal cortex. Prolonged treatment with canabidiol, 10mg/kg, prevented memory impairment in rats with pneumococcal meningitis. Although descriptive, our results demonstrate that cannabidiol has anti-inflammatory effects in pneumococcal meningitis and prevents cognitive sequel.

  14. Screening of hearing impairment in the newborn using the auditory response cradle.

    Science.gov (United States)

    Tucker, S M; Bhattacharya, J

    1992-01-01

    The Auditory Response Cradle (ARC) is a fully automated microprocessor controlled machine that was designed for the hearing screening of full term neonates. In order to evaluate the ARC, 6000 babies were screened at a district maternity hospital over a period of three years. Every infant subsequently entered a three year follow up programme. One hundred and two babies (1.7%) failed the ARC screen (that is, they failed two ARC tests) and 20 of these were found to have some hearing impairment: in 10 it was severe (80-90 dBHL), in seven moderate (45-60 dBHL), and in three it was mild to moderate (less than 45 dBHL). In addition, of the 20 babies who failed a first test and were discharged before a second could be performed, two were confirmed to have a severe hearing loss; 79 infants failing the screen were cleared on further testing, giving the ARC a false positive rate of 1.3%. On following up all 6000 infants for three years, seven children who passed the neonatal screen were subsequently found to have a hearing loss. For two babies the aetiology was unknown but for five the hearing impairment was either due to a hereditary progressive loss or definite postnatal factors. Progressive and acquired hearing losses cannot be detected at a neonatal screen and this emphasises the need for follow up screens at other stages in the child's life. In this long term study the ARC has been found to have a high detection rate for severe hearing loss and confirms the practical possibility of using a behavioural technique for the universal screening of hearing in neonates. Images Figure 1 Figure 2 PMID:1519957

  15. Inhibiting the NF-kappaB pathway to assess its function in the cellular response to space radiation

    Science.gov (United States)

    Koch, Kristina; Baumstark-Khan, Christa; Hellweg, Christine; Testard, Isabelle; Reitz, Guenther

    2012-07-01

    Radiation is regarded as one of the limiting factors for space missions. Therefore the cellular radiation response needs to be studied in order to estimate risks and to develop appropriate countermeasures. Exposure of human cells to ionizing radiation can provoke cell cycle arrest, leading to cellular senescence or premature differentiation, and different types of cell death. Previous heavy ion experiments have shown that the Nuclear Factor κB (NF-κB) pathway is activated by fluences that can be reached during long-term missions and thereby NF-κB was identified as an important modulating factor in the cellular radiation response. It could improve cellular survival after exposure to high radiation doses and influence the cancer risk of astronauts. The classical and the genotoxic stress induced NF-κB pathway result in nuclear translocation of the p65/p50 dimer. Both pathways might contribute to the cellular radiation response. Chemical inhibitors were tested to suppress the NF-κB pathway in recombinant HEK-pNF-κB-d2EGFP/Neo cells. The efficacy and cytotoxicity of the inhibitors targeting different elements of the NF-κB pathway were analyzed and found mostly inappropriate as inhibitors were partly cytotoxic or unspecific. Alternatively a functional knock-out of RelA (p65) was used to identify the contribution of the NF-κB pathway to different cellular outcomes. Small hairpin RNA constructs (shRNA) were transfected into the HEK-pNF-κB-d2EGFP/Neo cell line. Their functionality was assessed by quantitative Reverse Transcriptase real-time PCR (qRT-PCR) to verify that the RelA mRNA amount was reduced by more than 80% in the knock-down cells The original cell line had been stably transfected with a reporter system to monitor NF-κB activation by measuring destabilized Enhanced Green Fluorescent Protein (d2EGFP)-expression. It was shown that after 18 hours d2EGFP reaches its highest expression level after activation of NF-κB and can be measured by FACS analysis

  16. Oxidative stress impairs the heat stress response and delays unfolded protein recovery.

    Directory of Open Access Journals (Sweden)

    Masaaki Adachi

    Full Text Available BACKGROUND: Environmental changes, air pollution and ozone depletion are increasing oxidative stress, and global warming threatens health by heat stress. We now face a high risk of simultaneous exposure to heat and oxidative stress. However, there have been few studies investigating their combined adverse effects on cell viability. PRINCIPAL FINDINGS: Pretreatment of hydrogen peroxide (H(2O(2 specifically and highly sensitized cells to heat stress, and enhanced loss of mitochondrial membrane potential. H(2O(2 exposure impaired the HSP40/HSP70 induction as heat shock response (HSR and the unfolded protein recovery, and enhanced eIF2alpha phosphorylation and/or XBP1 splicing, land marks of ER stress. These H(2O(2-mediated effects mimicked enhanced heat sensitivity in HSF1 knockdown or knockout cells. Importantly, thermal preconditioning blocked H(2O(2-mediated inhibitory effects on refolding activity and rescued HSF1 +/+ MEFs, but neither blocked the effects nor rescued HSF1 -/- MEFs. These data strongly suggest that inhibition of HSR and refolding activity is crucial for H(2O(2-mediated enhanced heat sensitivity. CONCLUSIONS: H(2O(2 blocks HSR and refolding activity under heat stress, thereby leading to insufficient quality control and enhancing ER stress. These uncontrolled stress responses may enhance cell death. Our data thus highlight oxidative stress as a crucial factor affecting heat tolerance.

  17. Impaired ventilatory and thermoregulatory responses to hypoxic stress in newborn Phox2b heterozygous knockout mice

    Directory of Open Access Journals (Sweden)

    Nelina eRamanantsoa

    2011-09-01

    Full Text Available The Phox2b gene is necessary for the development of the autonomic nervous system, and especially, of respiratory neuronal circuits. In the present study, we examined the role of Phox2b in ventilatory and thermoregulatory responses to hypoxic stress, which are closely related in the postnatal period. Hypoxic stress was generated by strong thermal stimulus, combined or not with reduced inspired O2. To this end, we exposed 6-day-old Phox2b+/- pups and their wild-type littermates (Phox2b+/+ to hypoxia (10% O2 or hypercapnia (8% CO2 under thermoneutral (33°C or cold (26°C conditions. We found that Phox2b+/- pups showed less normoxic ventilation (VE in the cold than Phox2b+/+ pups. Phox2b+/- pups also showed lower oxygen consumption (VO2 in the cold, reflecting reduced thermogenesis and a lower body temperature. Furthermore, while the cold depressed ventilatory responses to hypoxia and hypercapnia in both genotype groups, this effect was less pronounced in Phox2b+/- pups. Finally, because serotonin (5-HT neurons are pivotal to respiratory and thermoregulatory circuits and depend on Phox2b for their differentiation, we studied 5-HT metabolism using high-pressure liquid chromatography, and found that it was altered in Phox2b+/- pups. We conclude that Phox2b haploinsufficiency alters the ability of newborns to cope with metabolic challenges, possibly due to 5-HT signaling impairments.

  18. Impaired innate immune response of leukocytes from ascitic fluid of patients with spontaneous bacterial peritonitis.

    Science.gov (United States)

    Nieto, Juan Camilo; Sánchez, Elisabet; Romero, Cristina; Román, Eva; Poca, Maria; Guarner, Carlos; Juárez, Cándido; Soriano, Germán; Vidal, Silvia

    2015-11-01

    An ascitic microenvironment can condition the immune response of cells from cirrhotic patients with spontaneous bacterial peritonitis. To characterize this response, we determined the cytokine concentrations in ascitic fluid and analyzed the phenotype and function of ascitic leukocytes at diagnosis and after antibiotic-induced resolution in sterile ascites and ascitic fluid of 2 spontaneous bacterial peritonitis variants: positive and negative bacteriological culture. At diagnosis, a high concentration was found of IL-6 and IL-10 in the ascitic fluid from negative and positive bacteriological culture. The IL-6 concentration correlated with the percentage of neutrophils (R = 0.686, P peritonitis burst was fully recovered. Higher concentrations of IL-6 and IL-10 correlated with the presence of low granular CD 14(low) macrophages (R = -0.436, P = 0.005 and R = 0.414, P = 0.007, respectively). Positive culture spontaneous bacterial peritonitis macrophages expressed the lowest levels of CD16, CD86, CD11b and CD206, and HLA-DR, suggesting an impaired global function. Treatment increased all markers on the positive culture macrophages and CD11b and CD86 on negative culture macrophages. In negative culture spontaneous bacterial peritonitis, this increase was accompanied by phagocytic function recovery. The antibiotics then reverted the marker levels on positive and negative culture macrophages to the levels on sterile ascitis macrophages and restored ascitic negative culture cell function.

  19. Salmonella enterica serovar Typhi impairs CD4 T cell responses by reducing antigen availability.

    Science.gov (United States)

    Atif, Shaikh M; Winter, Sebastian E; Winter, Maria G; McSorley, Stephen J; Bäumler, Andreas J

    2014-06-01

    Salmonella enterica serovar Typhi is associated with a disseminated febrile illness in humans, termed typhoid fever, while Salmonella enterica serovar Typhimurium causes localized gastroenteritis in immunocompetent individuals. One of the genetic differences between both pathogens is the presence in S. Typhi of TviA, a regulatory protein that shuts down flagellin (FliC) expression when bacteria transit from the intestinal lumen into the intestinal mucosa. Here we investigated the consequences of TviA-mediated flagellum gene regulation on flagellin-specific CD4 T cell responses in a mouse model of S. Typhimurium infection. Introduction of the S. Typhi tviA gene into S. Typhimurium suppressed antigen presentation of dendritic cells to flagellin-specific CD4 T cells in vitro. Furthermore, TviA-mediated repression of flagellin expression impaired the activation and proliferation of naive flagellin-specific CD4 T cells in Peyer's patches and mesenteric lymph nodes, which was accompanied by increased bacterial dissemination to the spleen. We conclude that TviA-mediated repression of flagellin expression reduces antigen availability, thereby weakening flagellin-specific CD4 T cell responses.

  20. Shp2 Deficiency Impairs the Inflammatory Response Against Haemophilus influenzae by Regulating Macrophage Polarization.

    Science.gov (United States)

    Zhao, Lifang; Xia, Jingyan; Li, Tiantian; Zhou, Hui; Ouyang, Wei; Hong, Zhuping; Ke, Yuehai; Qian, Jing; Xu, Feng

    2016-08-15

    Macrophages can polarize and differentiate to regulate initiation, development, and cessation of inflammation during pulmonary infection with nontypeable Haemophilus influenzae (NTHi). However, the underlying molecular mechanisms driving macrophage phenotypic differentiation are largely unclear. Our study investigated the role of Shp2, a Src homology 2 domain-containing phosphatase, in the regulation of pulmonary inflammation and bacterial clearance. Shp2 levels were increased upon NTHi stimulation. Selective inhibition of Shp2 in mice led to an attenuated inflammatory response by skewing macrophages toward alternatively activated macrophage (M2) polarization. Upon pulmonary NTHi infection, Shp2(-/-) mice, in which the gene encoding Shp2 in monocytes/macrophages was deleted, showed an impaired inflammatory response and decreased antibacterial ability, compared with wild-type controls. In vitro data demonstrated that Shp2 regulated activated macrophage (M1) gene expression via activation of p65-nuclear factor-κB signaling, independent of p38 and extracellular regulated kinase-mitogen-activated proteins kinase signaling pathways. Taken together, our study indicates that Shp2 is required to orchestrate macrophage function and regulate host innate immunity against pulmonary bacterial infection.

  1. Preserved hippocampal novelty responses following anterior temporal-lobe resection that impairs familiarity but spares recollection.

    Science.gov (United States)

    Bowles, Ben; O'Neil, Edward B; Mirsattari, Seyed M; Poppenk, Jordan; Köhler, Stefan

    2011-08-01

    Although it is well established that the integrity of the medial temporal lobe (MTL) is critical for declarative memory, the functional organization of the MTL remains a matter of intense debate. One issue that has received little consideration so far is whether the hippocampus can function normally in the presence of a lesion to perirhinal cortex that produces noticeable memory impairments. This question is intriguing as the MTL forms a hierarchical system, in which perirhinal cortex represents one of the critical nodes in the reciprocal projections between neocortical association areas and the hippocampus. Here, we used functional magnetic resonance imaging to examine whether NB, an individual who underwent surgical resection of the left anterior temporal lobe that included large aspects of perirhinal and entorhinal cortex but spared the hippocampus, exhibits intact hippocampal novelty responses to auditory sentences. Our results revealed such evidence in NB's left and right hippocampus. They complement previous behavioral work in NB, indicating that recollective processes considered to rely on hippocampal integrity are also preserved. Further analyses revealed intact novelty responses in structures that provide neuroanatomical input to the hippocampus, including remaining perirhinal cortex and surgically spared parahippocampal cortex. These findings point to viable neuroanatomical mechanisms as to how functional integrity in the hippocampus may be maintained in the face of widespread, but incomplete removal of its input structures.

  2. Immunosuppressive activity of Semen Persicae ethanol extract on specific antibody and cellular response to ovalbumin in mice.

    Science.gov (United States)

    Zhang, Yi-Bin; Qin, Feng; Sun, Hong-Xiang

    2006-09-01

    The immunosuppressive activity of the ethanol extract of Semen Persicae (EESP) was studied with respect to specific antibody and cellular response to ovalbumin (OVA) in mice. The effects of EESP on mice splenocyte proliferation in vitro were measured. EESP significantly suppressed concanavalin A (ConA)- and lipopolysaccharide (LPS)-stimulated splenocyte proliferation in vitro in a concentration-dependent manner. Furthermore, the effects of EESP at three dose levels on the humoral and cellular immune responses in the OVA-immunized mice were examined. ICR Mice were immunized subcutaneously with OVA on day 0 and 14. Starting on the day of immunization, the mice were administered intraperitoneally with EESP at a single dose of 0.25, 0.5, and 1.0 mg, and cyclosporin A (CsA, positive drug) at a single dose of 0.1 mg at intervals of 7 days. On day 28, mitogen- and OVA-induced splenocyte proliferation and OVA-specific antibody level in serum were measured. EESP significantly decreased ConA-, LPS-, and OVA-induced splenocyte proliferation in the OVA-immunized mice at the dose of 1.0 mg. Meanwhile, the OVA-specific serum IgG, IgG1, and IgG2b antibody levels in the OVA-immunized mice were markedly reduced by EESP in a dose-dependent manner. The results suggest that EESP could suppress the cellular and humoral immune response in mice, and deserve further research to be developed as immunosuppressant.

  3. Cellular and antibody response to respiratory syncytial (RS) virus in human colostrum, maternal blood, and cord blood.

    Science.gov (United States)

    Scott, R; Scott, M; Toms, G L

    1981-01-01

    Samples of colostrum, maternal blood, and cord blood from a group of 21 women were examined for the presence of cellular reactivity to respiratory syncytial (RS) virus using a transformation assay and for the level of specific IgA, and IgG, and IgM antibodies to RS virus by membrane immunofluorescence. Six of the 18 colostral cell cultures and six of the 16 maternal blood cultures gave a significant proliferative response to RS virus antigen, although a positive response in both local and systemic cell cultures was found in only one another. In addition, one of 18 samples of cord blood gave a proliferative response to RS virus antigen. Detectable titres of IgA antibodies to RS virus were found in 15 of the 20 samples of colostral whey and in 13 of the 17 samples of maternal plasma examined. RS virus-specific IgG antibodies were detected in 10 of 20 colostral whey samples and in all samples of maternal cord plasma. In this study, it was not possible to demonstrate a relationship between a positive proliferative response of colostral cell cultures to RS virus and the level of specific IgA and IgG antibodies in colostral whey. Similarly, the proliferative response of material blood cultures was unrelated to the titre of specific IgA or IgG antibodies in maternal plasma. The relevance of the local cellular proliferative response to RS virus in colostral cell cultures to the protection afforded by breast-feeding is discussed.

  4. Novel metastasis-related gene CIM functions in the regulation of multiple cellular stress-response pathways.

    Science.gov (United States)

    Yanagisawa, Kiyoshi; Konishi, Hiroyuki; Arima, Chinatsu; Tomida, Shuta; Takeuchi, Toshiyuki; Shimada, Yukako; Yatabe, Yasushi; Mitsudomi, Tetsuya; Osada, Hirotaka; Takahashi, Takashi

    2010-12-01

    Various stresses of the tumor microenvironment produced by insufficient nutrients, pH, and oxygen can contribute to the generation of altered metabolic and proliferative states that promote the survival of metastatic cells. Among many cellular stress-response pathways activated under such conditions are the hypoxia-inducible factor (HIF) pathway and the unfolded protein response (UPR), which is elicited as a response to endoplasmic reticulum (ER) stress. In this study, we report the identification of a novel cancer invasion and metastasis-related gene (hereafter referred to as CIM, also called ERLEC1), which influences both of these stress-response pathways to promote metastasis. CIM was identified by comparing the gene expression profile of a highly metastatic human lung cancer cell line with its weakly metastatic parental clone. We showed that CIM is critical for metastatic properties in this system. Proteomic approaches combined with bioinformatic analyses revealed that CIM has multifaceted roles in controlling the response to hypoxia and ER stress. Specifically, CIM sequestered OS-9 from the HIF-1α complex and PHD2, permitting HIF-1α accumulation by preventing its degradation. Ectopic expression of CIM in lung cancer cells increased their tolerance to hypoxia. CIM also modulated UPR through interaction with the key ER stress protein BiP, influencing cell proliferation under ER stress conditions. Our findings shed light on how tolerance to multiple cellular stresses at a metastatic site can be evoked by an integrated mechanism involving CIM, which can function to coordinate those responses in a manner that promotes metastatic cell survival.

  5. Effects of Spaceflight on Molecular and Cellular Responses to Bleomycin-Induced DNA Damages in Confluent Human Fibroblasts

    Science.gov (United States)

    Lu, Tao; Zhang, Ye; Wong, Michael; Stodieck, Louis; Karouia, Fathi; Wu, Honglu

    2016-01-01

    Spaceflights expose human beings to various risk factors. Among them are microgravity related physiological stresses in immune, cytoskeletal, and cardiovascular systems, and space radiation related elevation of cancer risk. Cosmic radiation consists of energetic protons and other heavier charged particles that induce DNA damages. Effective DNA damage response and repair mechanism is important to maintain genomic integrity and reduce cancer risk. There were studies on effects of spaceflight and microgravity on DNA damage response in cell and animal models, but the published results were mostly conflicting and inconsistent. To investigate effects of spaceflight on molecular and cellular responses to DNA damages, bleomycin, an anti-cancer drug and radiomimetic reagent, was used to induce DNA damages in confluent human fibroblasts flown to the International Space Station (ISS) and on ground. After exposure to 1.0 µg/ml bleomycin for 3 hours, cells were fixed for immunofluorescence assays and for RNA preparation. Extents of DNA damages were quantified by foci and pattern counting of phosphorylated histone protein H2AX (?-H2AX). The cells on the ISS showed modestly increased average foci counts per nucleus while the distribution of patterns was similar to that on the ground. PCR array analysis showed that expressions of several genes, including CDKN1A and PCNA, were significantly changed in response to DNA damages induced by bleomycin in both flight and ground control cells. However, there were no significant differences in the overall expression profile of DNA damage response genes between the flight and ground samples. Analysis of cellular proliferation status with Ki-67 staining showed a slightly higher proliferating population in cells on the ISS than those on ground. Our results suggested that the difference in ?-H2AX focus counts between flight and ground was due to the higher percentage of proliferating cells in space, but spaceflight did not significantly affect

  6. Mapping Variation in Cellular and Transcriptional Response to 1,25-Dihydroxyvitamin D3 in Peripheral Blood Mononuclear Cells.

    Directory of Open Access Journals (Sweden)

    Silvia N Kariuki

    Full Text Available The active hormonal form of vitamin D, 1,25-dihydroxyvitamin D (1,25D is an important modulator of the immune system, inhibiting cellular proliferation and regulating transcription of immune response genes. In order to characterize the genetic basis of variation in the immunomodulatory effects of 1,25D, we mapped quantitative traits of 1,25D response at both the cellular and the transcriptional level. We carried out a genome-wide association scan of percent inhibition of cell proliferation (Imax induced by 1,25D treatment of peripheral blood mononuclear cells from 88 healthy African-American individuals. Two genome-wide significant variants were identified: rs1893662 in a gene desert on chromosome 18 (p = 2.32 x 10-8 and rs6451692 on chromosome 5 (p = 2.55 x 10-8, which may influence the anti-proliferative activity of 1,25D by regulating the expression of nearby genes such as the chemokine gene, CCL28, and the translation initiation gene, PAIP1. We also identified 8 expression quantitative trait loci at a FDR<0.10 for transcriptional response to 1,25D treatment, which include the transcriptional regulator ets variant 3-like (ETV3L and EH-domain containing 4 (EHD4. In addition, we identified response eQTLs in vitamin D receptor binding sites near genes differentially expressed in response to 1,25D, such as FERM Domain Containing 6 (FRMD6, which plays a critical role in regulating both cell proliferation and apoptosis. Combining information from the GWAS of Imax and the response eQTL mapping enabled identification of putative Imax-associated candidate genes such as PAIP1 and the transcriptional repressor gene ZNF649. Overall, the variants identified in this study are strong candidates for immune traits and diseases linked to vitamin D, such as multiple sclerosis.

  7. Green propolis phenolic compounds act as vaccine adjuvants, improving humoral and cellular responses in mice inoculated with inactivated vaccines

    Directory of Open Access Journals (Sweden)

    Geferson Fischer

    2010-11-01

    Full Text Available Adjuvants play an important role in vaccine formulations by increasing their immunogenicity. In this study, the phenolic compound-rich J fraction (JFR of a Brazilian green propolis methanolic extract stimulated cellular and humoral immune responses when co-administered with an inactivated vaccine against swine herpesvirus type 1 (SuHV-1. When compared to control vaccines that used aluminium hydroxide as an adjuvant, the use of 10 mg/dose of JFR significantly increased (p < 0.05 neutralizing antibody titres against SuHV-1, as well as the percentage of protected animals following SuHV-1 challenge (p < 0.01. Furthermore, addition of phenolic compounds potentiated the performance of the control vaccine, leading to increased cellular and humoral immune responses and enhanced protection of animals after SuHV-1 challenge (p < 0.05. Prenylated compounds such as Artepillin C that are found in large quantities in JFR are likely to be the substances that are responsible for the adjuvant activity.

  8. DNA damage induction and/or repair as mammalian cell biomarker for the prediction of cellular radiation response

    Science.gov (United States)

    Baumstark-Khan, C.

    DNA damage and its repair processes are key factors in cancer induction and also in the treatment of malignancies. Cancer prevention during extended space missions becomes a topic of great importance for space radiobiology. The knowledge of individual responsiveness would allow the protection strategy to be tailored optimally in each case. Radiobiological analysis of cultured cells derived from tissue explants from individuals has shown that measurement of the surviving fraction after 2 Gy (SF2) may be used to predict the individual responsiveness. However, clonogenic assays are timeconsuming, thus alternative assays for the determination of radiore-sponse are being sought. For that reason CHO cell strains having different repair capacities were used for examining whether DNA strand break repair is a suitable experimental design to allow predictive statements. Cellular survival (CFA assay) and DNA strand breaks (total DNA strand breaks: FADU technique; DSBs: non-denaturing elution) were determined in parallel immediately after irradiation as well as after a 24 hour recovery period according to dose. There were no correlations between the dose-response curves of the initial level of DNA strand breaks and parameters that describe clonogenic survival curves (SF2). A good correlation exists between intrinsic cellular radioresistance and the extent of residual DNA strand breaks.

  9. Tetanus toxoid-loaded cationic non-aggregated nanostructured lipid particles triggered strong humoral and cellular immune responses.

    Science.gov (United States)

    Kaur, Amandeep; Jyoti, Kiran; Rai, Shweta; Sidhu, Rupinder; Pandey, Ravi Shankar; Jain, Upendra Kumar; Katyal, Anju; Madan, Jitender

    2016-05-01

    In the present investigation, non-aggregated cationic and unmodified nanoparticles (TT-C-NLPs4 and TT-NLPs1) were prepared of about 49.2 ± 6.8-nm and 40.8 ± 8.3-nm, respectively. In addition, spherical shape, crystalline architecture and cationic charge were also noticed. Furthermore, integrity and conformational stability of TT were maintained in both TT-C-NLPs4 and TT-NLPs1, as evidenced by symmetrical position of bands and superimposed spectra, respectively in SDS-PAGE and circular dichroism. Cellular uptake in RAW264.7 cells indicating the concentration-dependent internalisation of nanoparticles. Qualitatively, CLSM exhibited enhanced cellular uptake of non-aggregated TT-C-NLPs4 owing to interaction with negatively charged plasma membrane and clevaloe mediated/independent endocytosis. In last, in vivo immunisation with non-aggregated TT-C-NLPs4 elicited strong humoral (anti-TT IgG) and cellular (IFN-γ) immune responses at day 42, as compared to non-aggregated TT-NLPs1 and TT-Alum following booster immunisation at day 14 and 28. Thus, non-aggregated cationic lipid nanoparticles may be a potent immune-adjuvant for parenteral delivery of weak antigens.

  10. Specific cellular stimulation in the primary immune response: a quantized model.

    OpenAIRE

    1982-01-01

    A general theory for the initial phase of T cell independent immune response is derived from elementary physical-chemical considerations and from the premise that response entails a quantized linkage of cell surface receptors. The theory leads to the construction of explicit antigen dose--response and antigen dose--suppression curves, to the calculation of intrinsic affinities for receptors, and to the deduction that receptors are divalent in character. The theory may be applicable to other c...

  11. Sirtuin 7 promotes cellular survival following genomic stress by attenuation of DNA damage, SAPK activation and p53 response

    Energy Technology Data Exchange (ETDEWEB)

    Kiran, Shashi; Oddi, Vineesha [Laboratory of Cancer Biology, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana, 500001 (India); Ramakrishna, Gayatri, E-mail: gayatrirama1@gmail.com [Laboratory of Cancer Biology, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana, 500001 (India); Laboratory of Cancer Cell Biology, Department of Research, Institute of Liver and Biliary Sciences, Delhi 110070 (India)

    2015-02-01

    Maintaining the genomic integrity is a constant challenge in proliferating cells. Amongst various proteins involved in this process, Sirtuins play a key role in DNA damage repair mechanisms in yeast as well as mammals. In the present work we report the role of one of the least explored Sirtuin viz., SIRT7, under conditions of genomic stress when treated with doxorubicin. Knockdown of SIRT7 sensitized osteosarcoma (U2OS) cells to DNA damage induced cell death by doxorubicin. SIRT7 overexpression in NIH3T3 delayed cell cycle progression by causing delay in G1 to S transition. SIRT7 overexpressing cells when treated with low dose of doxorubicin (0.25 µM) showed delayed onset of senescence, lesser accumulation of DNA damage marker γH2AX and lowered levels of growth arrest markers viz., p53 and p21 when compared to doxorubicin treated control GFP expressing cells. Resistance to DNA damage following SIRT7 overexpression was also evident by EdU incorporation studies where cellular growth arrest was significantly delayed. When treated with higher dose of doxorubicin (>1 µM), SIRT7 conferred resistance to apoptosis by attenuating stress activated kinases (SAPK viz., p38 and JNK) and p53 response thereby shifting the cellular fate towards senescence. Interestingly, relocalization of SIRT7 from nucleolus to nucleoplasm together with its co-localization with SAPK was an important feature associated with DNA damage. SIRT7 mediated resistance to doxorubicin induced apoptosis and senescence was lost when p53 level was restored by nutlin treatment. Overall, we propose SIRT7 attenuates DNA damage, SAPK activation and p53 response thereby promoting cellular survival under conditions of genomic stress. - Highlights: • Knockdown of SIRT7 sensitized cells to DNA damage induced apoptosis. • SIRT7 delayed onset of premature senescence by attenuating DNA damage response. • Overexpression of SIRT7 delayed cell cycle progression by delaying G1/S transition. • Upon DNA damage SIRT

  12. MECANISMOS CELULARES EN RESPUESTA AL ESTRÉS:: SIRTUINAS Cellular mechanisms in response to stress: sirtuin

    Directory of Open Access Journals (Sweden)

    Nancy Paola Echeverri-Ruíz

    2010-07-01

    Full Text Available Desde hace algún tiempo se conoce el papel de la restricción calórica sobre la longevidad y la prevención de enfermedades crónicas, pero hasta hace poco los mecanismos celulares involucrados comienzan a ser elucidados. El estrés celular se podría definir como el estado en el que la célula no presenta las condiciones óptimas de supervivencia, siendo el oxidativo un tipo de estrés en el que se generan radicales libres nocivos para las estructuras celulares. La restricción calórica podría incrementar la resistencia celular a diferentes formas de estrés. Las sirtuinas, proteínas deacetilasas de histonas tipo III, están involucradas en la relación entre balance energético y transcripción génica, permitiendo que la célula responda a la restricción calórica y sobreviva a situaciones de estrés oxidativo. En esta relación las sirtuinas regulan genes de la familia FOXO, cMYC, hTERT, p53, entre otros. La activación o silenciamiento de estos genes es importante en los procesos de apoptosis, reparación y muerte celular.The role of caloric restriction on longevity and prevention of chronic diseases has been known for some time; recently, cellular mechanisms involved are beginning to be elucidated. Cellular stress could be defined as the state in which the cell does not present optimal survival conditions; oxidative stress is a type of stress in which free radicals harmful cell structures. Caloric restriction might increase cellular resistance to various forms of stress. Sirtuins, histone deacetylases type III proteins are involved in the relationship between energy balance and gene transcription, allowing cell to respond to caloric restriction and to survive to oxidative stress. In this relationship, sirtuins regulate FOXO family genes, cMYC, hTERT, p53, among others. Activation or silencing of those genes is important in the process of apoptosis, repair and cell death

  13. RETRACTED: The Nonlinear Compressive Response and Deformation of an Auxetic Cellular Structure under In-Plane Loading

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2015-01-01

    Full Text Available At the request of the Author, the following article Zhang, W, Hou, W, Hu, Ping and Ma, Z (2014 The Nonlinear Compressive Response and Deformation of an Auxetic Cellular Structure under In-Plane Loading Advances in Mechanical Engineering published 17 November 2014. doi: 10.1155/2014/214681has been retracted due to errors discovered by the authors. On Page 3, the definition of component force in Equation 4 is incorrect. (2 On Page 4, the definition of component force in Equation 11 is incorrect. Moreover this equation should not have parameterM(length of cell wall, because a mistake was made in the process of calculation. Because of the above reasons, the conclusion obtained from the mechanical model is incorrect and should instead state that the Elastic Buckling and Plastic Collapse are both yield modes of this structure (3 On Page 5, the FEA model used in this article is not appropriate, because the deformation of single cell is not homogeneous, which means that the geometrical non-linear effect on single cell model is greater. So in the actual whole structure we may not obtain the results that were described in Page 6 Paragraph 2. (4 The data in figures 8 (page 6 and 9 (page 7 is incorrect and the values of effective Young’s modulus and plateau stress are much larger than reasonable values. The definition of effective stress is wrong in the FEA model, which means the effective stress should be calculated by the total width of cell instead of length of horizontal cell wall. For example, in Figure 8, the plateau stress can reach 140Mpa, this is not reasonable because there are many holes in this cellular structure, and its mechanical properties should be much lower than material properties of cell wall. The reasonable plateau stress should be around 2Mpa. The authors takes responsibility for these errors and regret the publication of invalid results. The nonlinear compressive response and deformation of an auxetic cellular structure that has

  14. Comprehensive interrogation of the cellular response to fluorescent, detonation and functionalized nanodiamonds

    Science.gov (United States)

    Moore, Laura; Grobárová, Valéria; Shen, Helen; Man, Han Bin; Míčová, Júlia; Ledvina, Miroslav; Štursa, Jan; Nesladek, Milos; Fišerová, Anna; Ho, Dean

    2014-09-01

    Nanodiamonds (NDs) are versatile nanoparticles that are currently being investigated for a variety of applications in drug delivery, biomedical imaging and nanoscale sensing. Although initial studies indicate that these small gems are biocompatible, there is a great deal of variability in synthesis methods and surface functionalization that has yet to be evaluated. Here we present a comprehensive analysis of the cellular compatibility of an array of nanodiamond subtypes and surface functionalization strategies. These results demonstrate that NDs are well tolerated by multiple cell types at both functional and gene expression levels. In addition, ND-mediated delivery of daunorubicin is less toxic to multiple cell types than treatment with daunorubicin alone, thus demonstrating the ability of the ND agent to improve drug tolerance and decrease therapeutic toxicity. Overall, the results here indicate that ND biocompatibility serves as a promising foundation for continued preclinical investigation.

  15. Comprehensive interrogation of the cellular response to fluorescent, detonation and functionalized nanodiamonds.

    Science.gov (United States)

    Moore, Laura; Grobárová, Valéria; Shen, Helen; Man, Han Bin; Míčová, Júlia; Ledvina, Miroslav; Štursa, Jan; Nesladek, Milos; Fišerová, Anna; Ho, Dean

    2014-10-21

    Nanodiamonds (NDs) are versatile nanoparticles that are currently being investigated for a variety of applications in drug delivery, biomedical imaging and nanoscale sensing. Although initial studies indicate that these small gems are biocompatible, there is a great deal of variability in synthesis methods and surface functionalization that has yet to be evaluated. Here we present a comprehensive analysis of the cellular compatibility of an array of nanodiamond subtypes and surface functionalization strategies. These results demonstrate that NDs are well tolerated by multiple cell types at both functional and gene expression levels. In addition, ND-mediated delivery of daunorubicin is less toxic to multiple cell types than treatment with daunorubicin alone, thus demonstrating the ability of the ND agent to improve drug tolerance and decrease therapeutic toxicity. Overall, the results here indicate that ND biocompatibility serves as a promising foundation for continued preclinical investigation.

  16. Effect of tylosin tartrate (Tylan Soluble) on cellular immune responses in chickens.

    Science.gov (United States)

    Baba, T; Yamashita, N; Kodama, H; Mukamoto, M; Asada, M; Nakamoto, K; Nose, Y; McGruder, E D

    1998-09-01

    Although many antimicrobial agents have been reported to cause immunosuppression in animals, macrolide antibiotics enhance immune function. Tylosin is a macrolide antibiotic approved for the control of mycoplasmosis in poultry. The purpose of this investigation was to determine the effect of tylosin on cellular immune functions in chickens. There was no significant difference in adherent splenocyte chemotaxis between tylosin-treated and untreated (control) chickens. Tylosin increased splenocyte proliferation and splenocyte conditioned medium (CM) proliferative activity above control levels. Removal of adherent splenocytes before preparation of CM caused a reduction in CM proliferative activity. Tylosin also increased antitumor activity of splenocytes. These data are the first to suggest that the macrolide antibiotic, tylosin tartrate, has a modulatory effect in chickens on the immune parameters studied.

  17. Molecular and cellular response of earthworm Eisenia andrei (Oligochaeta, Lumbricidae) to PCDD/Fs exposure.

    Science.gov (United States)

    Nusair, Shreen Deeb; Abu Zarour, Yousef Sa'id

    2017-01-01

    The acute toxicity of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) was investigated in the earthworm Eisenia andrei using filter paper toxicity test. Protein content, catalase (CAT) activity, and histology of intestinal wall (chloragogen cells and intestinal epithelium) were investigated in earthworms exposed for 48 h to 0 (control), 0.5, 1.0, and 1.5 ng/cm(2) PCDD/Fs. The results showed an increase in the total protein content 1.56- (p = 0.104), 1.66- (p = 0.042), and 2.26-fold (p biomarkers of E. andrei within 48 h, the cellular and molecular alterations resulted from the filter paper contact test could be utilized as a rapid toxicity assessment tool of environmental contamination with dioxins/furans and to assess consequent potential adverse effects on soil biota and other organisms in the ecosystem.

  18. Polyacrylamide scaffolds for studying cellular response to substrate stiffness in three dimensions

    Science.gov (United States)

    Lin, Keng-Hui

    2013-03-01

    Recent developments in two-dimensional (2D) culture substrates with tunable stiffness and patterned adhesion ligands have demonstrated that biochemical and mechanical cues regulate the biological functions of living cells. We have extended these cell culture platforms into three dimensions (3D), as in complex biological systems, by producing highly ordered scaffolds of polyacrylamide coated with extracellular matrix proteins. We characterized parameters for the scaffold fabrication. We then grew individual fibroblasts in the identical pores of our scaffolds, examing cellular morphological, cytoskeletal, and adhesion properties. We have observed rich variety of morphologies and anchoring strategies assumed by cells growing on our tunable 3D polyacrylamide scaffolds to demonstrate the richness of cell-mciroenvironment interactions when cell adhesions are not confined to 2D surfaces.

  19. Molecular events basic to cellular radiation response. Progress report, July 1, 1976--September 30, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Kolodny, G.M.

    1977-01-01

    Progress is reported on studies of the effects of x irradiation at the cellular level that lead ultimately to either malignant transformation or cell death. Experimental results consistent with the primer hypothesis for the regulation of gene expression in eukaryotes are reported. It was found that oligonucleotides can be inserted en bloc into newly synthesized RNA. Studies on amino acid-nucleic acid interactions were continued by successfully synthesizing an amidate and beginning NMR studies on the interactions between its nucleic acid and amino acid moieties. In studies on radiation induced giant cells in 3T3 cells growing in culture, it was demonstrated that conditions which potentiate potential lethal damage repair and those which prevent radiation induced giant cell formation exist. In an examination of the in vitro effects of vasopressin, no direct effect was found of vasopressin on radiation sensitivity and significant effects of radiation on lysosomal enzyme activity in cultured cells were found.

  20. Redox regulation of human OGG1 activity in response to cellular oxidative stress.

    Science.gov (United States)

    Bravard, Anne; Vacher, Monique; Gouget, Barbara; Coutant, Alexandre; de Boisferon, Florence Hillairet; Marsin, Stéphanie; Chevillard, Sylvie; Radicella, J Pablo

    2006-10-01

    8-Oxoguanine (8-oxoG), a common and mutagenic form of oxidized guanine in DNA, is eliminated mainly through base excision repair. In human cells its repair is initiated by human OGG1 (hOGG1), an 8-oxoG DNA glycosylase. We investigated the effects of an acute cadmium exposure of human lymphoblastoid cells on the activity of hOGG1. We show that coinciding with alteration of the redox cellular status, the 8-oxoG DNA glycosylase activity of hOGG1 was nearly completely inhibited. However, the hOGG1 activity returned to normal levels once the redox cellular status was normalized. In vitro, the activity of purified hOGG1 was abolished by cadmium and could not be recovered by EDTA. In cells, however, the reversible inactivation of OGG1 activity by cadmium was strictly associated with reversible oxidation of the protein. Moreover, the 8-oxoG DNA glycosylase activity of purified OGG1 and that from crude extracts were modulated by cysteine-modifying agents. Oxidation of OGG1 by the thiol oxidant diamide led to inhibition of the activity and a protein migration pattern similar to that seen in cadmium-treated cells. These results suggest that cadmium inhibits hOGG1 activity mainly by indirect oxidation of critical cysteine residues and that excretion of the metal from the cells leads to normalization of the redox cell status and restoration of an active hOGG1. The results presented here unveil a novel redox-dependent mechanism for the regulation of OGG1 activity.

  1. Investigation of cellular and molecular responses to pulsed focused ultrasound in a mouse model.

    Directory of Open Access Journals (Sweden)

    Scott R Burks

    Full Text Available Continuous focused ultrasound (cFUS has been widely used for thermal ablation of tissues, relying on continuous exposures to generate temperatures necessary to induce coagulative necrosis. Pulsed FUS (pFUS employs non-continuous exposures that lower the rate of energy deposition and allow cooling to occur between pulses, thereby minimizing thermal effects and emphasizing effects created by non-thermal mechanisms of FUS (i.e., acoustic radiation forces and acoustic cavitation. pFUS has shown promise for a variety of applications including drug and nanoparticle delivery; however, little is understood about the effects these exposures have on tissue, especially with regard to cellular pro-homing factors (growth factors, cytokines, and cell adhesion molecules. We examined changes in murine hamstring muscle following pFUS or cFUS and demonstrate that pFUS, unlike cFUS, has little effect on the histological integrity of muscle and does not induce cell death. Infiltration of macrophages was observed 3 and 8 days following pFUS or cFUS exposures. pFUS increased expression of several cytokines (e.g., IL-1α, IL-1β, TNFα, INFγ, MIP-1α, MCP-1, and GMCSF creating a local cytokine gradient on days 0 and 1 post-pFUS that returns to baseline levels by day 3 post-pFUS. pFUS exposures induced upregulation of other signaling molecules (e.g., VEGF, FGF, PlGF, HGF, and SDF-1α and cell adhesion molecules (e.g., ICAM-1 and VCAM-1 on muscle vasculature. The observed molecular changes in muscle following pFUS may be utilized to target cellular therapies by increasing homing to areas of pathology.

  2. Estrogen receptor 2b deficiency impairs the antiviral response of zebrafish.

    Science.gov (United States)

    López-Muñoz, Azucena; Liarte, Sergio; Gómez-González, Nuria E; Cabas, Isabel; Meseguer, José; García-Ayala, Alfonsa; Mulero, Victoriano

    2015-11-01

    Although several studies have demonstrated the ability of some endocrine disruptive chemicals (EDCs) to alter the physiology of zebrafish, the immune-reproductive interaction has received little attention in this species. In this study, we used a homozygous line carrying an insertion of 8 amino acids in the ligand-binding domain of the estrogen receptor 2b gene (esr2b) to further understand the role of estrogen signaling on innate immunity. Adult mutant fish showed distorted sexual ratios related with alterations in testicular morphology and supraphysiological testosterone and 17β-estradiol (E2) levels. Immunity-wise, although esr2b mutant fish showed unaltered antibacterial responses, they were unable to mount an effective antiviral response upon viral challenge. RT-qPCR analysis demonstrated that mutant fish were able to induce the genes encoding major antiviral molecules, including Ifnphi1, Ifnphi2, Infphi3, Mxb and Mxc, and the negative feedback regulator of cytokine signaling Socs1. Notably, although esr2b mutant larvae showed a similar resistance to SVCV infection to their wild type siblings, waterborne E2 increased their viral susceptibility. Similarly, the exposure of adult wild type zebrafish to E2 also resulted in increased susceptibility to SVCV infection. Finally, the administration of recombinant Ifnphi1 hardly reversed the higher viral susceptibility of esr2b mutant zebrafish, suggesting that elevated socs1 levels impair Ifn signaling. All together, these results uncover an important role for E2 and Esr signaling in the fine-tuning of sexual hormone balance and the antiviral response of vertebrates.

  3. Sae regulator factor impairs the response to photodynamic inactivation mediated by Toluidine blue in Staphylococcus aureus.

    Science.gov (United States)

    Gándara, Lautaro; Mamone, Leandro; Dotto, Cristian; Buzzola, Fernanda; Casas, Adriana

    2016-12-01

    Photodynamic inactivation (PDI) involves the combined use of light and a photosensitizer, which, in the presence of oxygen, originates cytotoxic species capable of inactivating bacteria. Since the emergence of multi-resistant bacterial strains is becoming an increasing public health concern, PDI becomes an attractive choice. The aim of this work was to study the differential susceptibility to Toluidine blue (TB) mediated PDI (TB-PDI) of S. aureus mutants (RN6390 and Newman backgrounds) for different key regulators of virulence factors related to some extent to oxidative stress. Complete bacteria eradication of planktonic cultures of RN6390 S. aureus photosensitized with 13μM TB was obtained upon illumination with a low light dose of 4.2J/cm(2) from a non-coherent light source. Similarly, complete cell death was achieved applying 1.3μM TB and 19J/cm(2) light dose, showing that higher light doses can lead to equal cell death employing low photosensitizer concentrations. Interestingly, RN6390 in planktonic culture responded significantly better to TB-PDI than the Newman strain. We showed that deficiencies in rsbU, mgrA (transcription factors related to stress response) or agr (quorum sensing system involved in copper resistance to oxidative stress) did not modify the response of planktonic S. aureus to PDI. On the other hand, the two component system sae impaired the response to TB-PDI through a mechanism not related to the Eap adhesin. More severe conditions were needed to inactivate S. aureus biofilms (0.5mM TB, 157J/cm(2) laser light). In mutant sae biofilms, strain dependant differential susceptibilities are not noticed.

  4. Tumor Necrosis Factor-α -and Interleukin-1-Induced Cellular Responses: Coupling Proteomic and Genomic Information

    Science.gov (United States)

    Ott, Lee W.; Resing, Katheryn A.; Sizemore, Alecia W.; Heyen, Joshua W.; Cocklin, Ross R.; Pedrick, Nathan M.; Woods, H. Cary; Chen, Jake Y.; Goebl, Mark G.; Witzmann, Frank A.; Harrington, Maureen A.

    2010-01-01

    The pro-inflammatory cytokines, Tumor Necrosis Factor-alpha (TNFα) and Interleukin-1 (IL-1) mediate the innate immune response. Dysregulation of the innate immune response contributes to the pathogenesis of cancer, arthritis, and congestive heart failure. TNFα- and IL-1-induced changes in gene expression are mediated by similar transcription factors; however, TNFα and IL-1 receptor knock-out mice differ in their sensitivities to a known initiator (lipopolysaccharide, LPS) of the innate immune response. The contrasting responses to LPS indicate that TNFα and IL-1 regulate different processes. A large-scale proteomic analysis of TNFα- and IL-1-induced responses was undertaken to identify processes uniquely regulated by TNFα and IL-1. When combined with genomic studies, our results indicate that TNFα, but not IL-1, mediates cell cycle arrest. PMID:17503796

  5. Tumor Necrosis Factor-alpha- and interleukin-1-induced cellular responses: coupling proteomic and genomic information.

    Science.gov (United States)

    Ott, Lee W; Resing, Katheryn A; Sizemore, Alecia W; Heyen, Joshua W; Cocklin, Ross R; Pedrick, Nathan M; Woods, H Cary; Chen, Jake Y; Goebl, Mark G; Witzmann, Frank A; Harrington, Maureen A

    2007-06-01

    The pro-inflammatory cytokines, Tumor Necrosis Factor-alpha (TNFalpha) and Interleukin-1 (IL-1) mediate the innate immune response. Dysregulation of the innate immune response contributes to the pathogenesis of cancer, arthritis, and congestive heart failure. TNFalpha- and IL-1-induced changes in gene expression are mediated by similar transcription factors; however, TNFalpha and IL-1 receptor knock-out mice differ in their sensitivities to a known initiator (lipopolysaccharide, LPS) of the innate immune response. The contrasting responses to LPS indicate that TNFalpha and IL-1 regulate different processes. A large-scale proteomic analysis of TNFalpha- and IL-1-induced responses was undertaken to identify processes uniquely regulated by TNFalpha and IL-1. When combined with genomic studies, our results indicate that TNFalpha, but not IL-1, mediates cell cycle arrest.

  6. Respiratory Syncytial Virus Persistence in Murine Macrophages Impairs IFN-β Response but Not Synthesis

    Directory of Open Access Journals (Sweden)

    Evelyn Rivera-Toledo

    2015-10-01

    Full Text Available Type-I interferon (IFN-I production is an early response to viral infection and pathogenic viruses have evolved multiple strategies to evade this cellular defense. Some viruses can establish and maintain persistent infections by altering the IFN-I signaling pathway. Here, we studied IFN-I synthesis and response in an in vitro model of persistent infection by respiratory syncytial virus (RSV in a murine macrophage-like cell line. In this model, interferon regulatory factor 3 was constitutively active and located at nuclei of persistently infected cells, inducing expression of IFN-beta mRNA and protein. However, persistently infected macrophages did not respond in an autocrine manner to the secreted-IFN-beta or to recombinant-IFN-beta, since phosphorylated-STAT1 was not detected by western blot and transcription of the interferon-stimulated genes (ISGs Mx1 and ISG56 was not induced. Treatment of non-infected macrophages with supernatants from persistently infected cells induced STAT1 phosphorylation and ISGs expression, mediated by the IFN-I present in the supernatants, because blocking the IFN-I receptor inhibited STAT1 phosphorylation. Results suggest that the lack of autocrine response to IFN-I by the host cell may be one mechanism for maintenance of RSV persistence. Furthermore, STAT1 phosphorylation and ISGs expression induced in non-infected cells by supernatants from persistently infected macrophages suggest that RSV persistence may trigger a proinflammatory phenotype in non-infected cells as part of the pathogenesis of RSV infection.

  7. Humoral and Cellular Responses to a Single Dose of Fendrix in Renal Transplant Recipients with Non-response to Previous Hepatitis B Vaccination.

    Science.gov (United States)

    Lindemann, M; Zaslavskaya, M; Fiedler, M; Wilde, B; Heinemann, F M; Heinold, A; Horn, P A; Witzke, O

    2017-01-01

    Approximately 70% of kidney transplant recipients are non-responders to conventional hepatitis B virus (HBV) vaccines. We examined whether Fendrix™, an HBV vaccine containing 3-O-desacyl-4'-monophosphoryl lipid A (MPL) as adjuvant, could induce HBV immunity in these patients and compared their vaccination efficacy with healthy controls tested previously by the same assays. We selected 35 kidney transplant recipients who had been vaccinated at least thrice against HBV but had never displayed anti-HBs antibodies. We re-assessed their anti-HBs antibody titres and further determined cellular HBV immunity by proliferation assay and interferon (IFN)-γ ELISpot. Seventeen recipients did neither display humoral nor cellular immunity and could be tested prior to and at month 1 after vaccination. Of note, HLA antigens associated with non-response to HBV vaccination (HLA-DRB1*03 and HLA-DQB1*02) were over-represented in these 17 recipients. At month 1 after a single vaccination with Fendrix™, we observed a significant increase in anti-HBs antibodies (P = 0.02). In seven of 17 recipients, we detected anti-HBs antibodies ≥10 IU/l (10-264), in four HBV-specific lymphocyte proliferation (stimulation index of 2.6-8.7) and in one specific IFN-γ responses (12 spots increment). The vaccination response to Fendrix™ was significantly higher (P = 0.035) than the response to HBVaxPro™ in young healthy controls. In summary, the results show that a single vaccination with Fendrix(™) could already induce HBV-specific humoral and/or cellular responses in ten of 17 kidney transplant patients. Thus, Fendrix™ appears as an efficient vaccine in this patient cohort. © 2016 The Foundation for the Scandinavian Journal of Immunology.

  8. Modification to the capsid of the adenovirus vector that enhances dendritic cell infection and transgene-specific cellular immune responses.

    Science.gov (United States)

    Worgall, Stefan; Busch, Annette; Rivara, Michael; Bonnyay, David; Leopold, Philip L; Merritt, Robert; Hackett, Neil R; Rovelink, Peter W; Bruder, Joseph T; Wickham, Thomas J; Kovesdi, Imi; Crystal, Ronald G

    2004-03-01

    Adenovirus (Ad) gene transfer vectors can be used to transfer and express antigens and function as strong adjuvants and thus are useful platforms for the development of genetic vaccines. Based on the hypothesis that Ad vectors with enhanced infectibility of dendritic cells (DC) may be able to evoke enhanced immune responses against antigens encoded by the vector in vivo, the present study analyzes the vaccine potential of an Ad vector expressing beta-galactosidase as a model antigen and genetically modified with RGD on the fiber knob [AdZ.F(RGD)] to more selectively infect DC and consequently enhance immunity against the beta-galactosidase antigen. Infection of murine DC in vitro with AdZ.F(RGD) showed an eightfold-increased transgene expression following infection compared to AdZ (also expressing beta-galactosidase, but with a wild-type capsid). Binding, cellular uptake, and trafficking in DC were also increased with AdZ.F(RGD) compared to AdZ. To determine whether AdZ.F(RGD) could evoke enhanced immune responses to beta-galactosidase in vivo, C57BL/6 mice were immunized with AdZ.F(RGD) or AdZ subcutaneously via the footpad. Humoral responses with both vectors were comparable, with similar anti-beta-galactosidase antibody levels following vector administration. However, cellular responses to beta-galactosidase were significantly enhanced, with the frequency of CD4(+) as well as the CD8(+) beta-galactosidase-specific gamma interferon response in cells isolated from the draining lymph nodes increased following immunization with AdZ.F(RGD) compared to Ad.Z (P AdZ.F(RGD) vector was sufficient to evoke enhanced inhibition of the growth of preexisting tumors expressing beta-galactosidase: BALB/c mice implanted with the CT26 syngeneic beta-galactosidase-expressing colon carcinoma cell line and subsequently immunized with AdZ.F(RGD) showed decreased tumor growth and improved survival compared to mice immunized with AdZ. These data demonstrate that addition of an RGD motif

  9. Visual impairment secondary to congenital glaucoma in children: visual responses, optical correction and use of low vision AIDS.

    Science.gov (United States)

    Haddad, Maria Aparecida Onuki; Sampaio, Marcos Wilson; Oltrogge, Ernst Werner; Kara-José, Newton; Betinjane, Alberto Jorge

    2009-01-01

    Congenital glaucoma is frequently associated with visual impairment due to optic nerve damage, corneal opacities, cataracts and amblyopia. Poor vision in childhood is related to global developmental problems, and referral to vision habilitation/rehabilitation services should be without delay to promote efficient management of the impaired vision. To analyze data concerning visual response, the use of optical correction and prescribed low vision aids in a population of children with congenital glaucoma. The authors analyzed data from 100 children with congenital glaucoma to assess best corrected visual acuity, prescribed optical correction and low vision aids. Fifty-five percent of the sample were male, 43% female. The mean age was 6.3 years. Two percent presented normal visual acuity levels, 29% mild visual impairment, 28% moderate visual impairment, 15% severe visual impairment, 11% profound visual impairment, and 15% near blindness. Sixty-eight percent received optical correction for refractive errors. Optical low vision aids were adopted for distance vision in 34% of the patients and for near vision in 6%. A manual monocular telescopic system with 2.8 x magnification was the most frequently prescribed low vision aid for distance, and for near vision a +38 diopter illuminated stand magnifier was most frequently prescribed. Careful low vision assessment and the appropriate prescription of optical corrections and low vision aids are mandatory in children with congenital glaucoma, since this will assist their global development, improving efficiency in daily life activities and promoting social and educational inclusion.

  10. Comparison of two models of hemispheric specialization with unilaterally lesioned patients: material-specific impairment vs response-bias distortion.

    Science.gov (United States)

    Guimond, Anik; Braun, Claude M J; Daigneault, Sylvie; Farmer, Jean-Pierre

    2013-10-01

    Validity of two models of hemispheric specialization was compared. The "material-specific impairment" model was radicalized as postulating that left hemisphere (LH) lesions impair processing of verbal material and that right hemisphere (RH) lesions impair processing of visuospatial material, independently of response-bias distortions. The "response-bias distortion" model was radicalized as postulating that LH lesions distort response style toward omissiveness and that RH lesions distort response style toward commissiveness, regardless of material-specific impairments. Participants had comparable left (N=27) or right (N=24) hemisphere cortical lesions having occurred between birth and early adolescence. Four cognitive neuropsychological tests were adjusted to optimize applicability and comparability of the two theoretical models: Rey Complex Figure, Kimura's Recurring Figures, the Story Recall subtest of the Children's Memory Scale, and the California Verbal Learning Test. Both models significantly, independently, and equally distinguished the LH from the RH patients. Both these forms of hemispheric specialization seemed to be implemented very early in life and very rigidly. Intrahemispheric lesion sites, e.g., frontal vs nonfrontal, held no significant relation to the effects described above.

  11. Social communication impairments in children and adolescents with Asperger syndrome: Slow response time and the impact of prompting

    DEFF Research Database (Denmark)

    Kaland, Nils; Mortensen, Erik Lykke; Smith, Lars

    2011-01-01

    , and understanding intentions. The participants in the AS group showed significant impairments in social communication. They needed significantly longer response times to solve the tasks and required significantly more prompt questions than the control persons. When analyzing the AS participants' performances before...

  12. Overproduction of a Model Sec- and Tat-Dependent Secretory Protein Elicits Different Cellular Responses in Streptomyces lividans.

    Directory of Open Access Journals (Sweden)

    Sonia Gullón

    Full Text Available Streptomyces lividans is considered an efficient host for the secretory production of homologous and heterologous proteins. To identify possible bottlenecks in the protein production process, a comparative transcriptomic approach was adopted to study cellular responses during the overproduction of a Sec-dependent model protein (alpha-amylase and a Tat-dependent model protein (agarase in Streptomyces lividans. The overproduction of the model secretory proteins via the Sec or the Tat route in S. lividans does elicit a different major cell response in the bacterium. The stringent response is a bacterial response to nutrients' depletion, which naturally occurs at late times of the bacterial cell growth. While the induction of the stringent response at the exponential phase of growth may limit overall productivity in the case of the Tat route, the induction of that response does not take place in the case of the Sec route, which comparatively is an advantage in secretory protein production processes. Hence, this study identifies a potential major drawback in the secretory protein production process depending on the secretory route, and provides clues to improving S. lividans as a protein production host.

  13. Overproduction of a Model Sec- and Tat-Dependent Secretory Protein Elicits Different Cellular Responses in Streptomyces lividans.

    Science.gov (United States)

    Gullón, Sonia; Marín, Silvia; Mellado, Rafael P

    2015-01-01

    Streptomyces lividans is considered an efficient host for the secretory production of homologous and heterologous proteins. To identify possible bottlenecks in the protein production process, a comparative transcriptomic approach was adopted to study cellular responses during the overproduction of a Sec-dependent model protein (alpha-amylase) and a Tat-dependent model protein (agarase) in Streptomyces lividans. The overproduction of the model secretory proteins via the Sec or the Tat route in S. lividans does elicit a different major cell response in the bacterium. The stringent response is a bacterial response to nutrients' depletion, which naturally occurs at late times of the bacterial cell growth. While the induction of the stringent response at the exponential phase of growth may limit overall productivity in the case of the Tat route, the induction of that response does not take place in the case of the Sec route, which comparatively is an advantage in secretory protein production processes. Hence, this study identifies a potential major drawback in the secretory protein production process depending on the secretory route, and provides clues to improving S. lividans as a protein production host.

  14. Effects of lactoferrin on elicitation of the antigen-specific cellular and humoral cutaneous response in mice

    Directory of Open Access Journals (Sweden)

    Michał Zimecki

    2012-01-01

    Full Text Available Immune contact dermatitis is an inflammation of the skin resulting from exposure to allergens in the environment. The aim of this study was to compare the actions of lactoferrin (LF, a natural immunomodulator, on the elicitation phases of the cellular and humoral, cutaneous immune responses to oxazolone and toluene diisocyanate (TDI, respectively. LF was given i.v. in a 10 mg/mouse dose, together with the eliciting doses of the antigens. The ear edema and the number of lymphocytes in the draining lymph nodes were measured. In addition, the production of IL-2 in the cultures of lymph node cells and the content of IL-4 in lymph node cells were determined. LF had a profound inhibitory effect on the eliciting phase of the immune response to oxazolone as measured by the ear edema and lymph node cell number. The suppressive effect of LF on the effector phase of the immune response to TDI was moderate. LF had some stimulatory effect on the ex vivo content of IL-4 in lymphocytes in the immune response to TDI. On the other hand, it significantly inhibited IL-2 in vitro production in the immune response to oxazolone. The data strongly suggest that LF exerted differential actions on the activities of antigen-specific Th1 and Th2 cells involved in respective types of the cutaneous immune responses.

  15. Overproduction of a Model Sec- and Tat-Dependent Secretory Protein Elicits Different Cellular Responses in Streptomyces lividans

    Science.gov (United States)

    Gullón, Sonia; Marín, Silvia; Mellado, Rafael P.

    2015-01-01

    Streptomyces lividans is considered an efficient host for the secretory production of homologous and heterologous proteins. To identify possible bottlenecks in the protein production process, a comparative transcriptomic approach was adopted to study cellular responses during the overproduction of a Sec-dependent model protein (alpha-amylase) and a Tat-dependent model protein (agarase) in Streptomyces lividans. The overproduction of the model secretory proteins via the Sec or the Tat route in S. lividans does elicit a different major cell response in the bacterium. The stringent response is a bacterial response to nutrients’ depletion, which naturally occurs at late times of the bacterial cell growth. While the induction of the stringent response at the exponential phase of growth may limit overall productivity in the case of the Tat route, the induction of that response does not take place in the case of the Sec route, which comparatively is an advantage in secretory protein production processes. Hence, this study identifies a potential major drawback in the secretory protein production process depending on the secretory route, and provides clues to improving S. lividans as a protein production host. PMID:26200356

  16. Skin Blood Perfusion and Cellular Response to Insertion of Insulin Pen Needles With Different Diameters

    DEFF Research Database (Denmark)

    Præstmark, Kezia Ann; Stallknecht, Bente Merete; Bo Jensen, Casper

    2014-01-01

    Today most research on pen needle design revolves around pain perception statements through clinical trials, but these are both costly, timely, and require high sample sizes. The purpose of this study was to test if tissue damage, caused by different types of needles, can be assessed by evaluating...... skin blood perfusion response around needle insertion sites. Three common sized pen needles of 28G, 30G, and 32G as well as hooked 32G needles, were inserted into the neck skin of pigs and then removed. Laser Speckle Contrast Analysis was used to measure skin blood perfusion for 20 minutes after......, but there was a trend of an increased response with increasing needle diameter. Skin blood perfusion response to pen needle insertions rank according to needle diameter, and the tissue response caused by hooked 32G needles corresponds to that of 28G needles. The relation between needle diameter and trauma when...

  17. Vaccination with dengue virus-like particles induces humoral and cellular immune responses in mice

    National Research Council Canada - National Science Library

    Zhang, Shuo; Liang, Mifang; Gu, Wen; Li, Chuan; Miao, Fang; Wang, Xiaofang; Jin, Cong; Zhang, Li; Zhang, Fushun; Zhang, Quanfu; Jiang, Lifang; Li, Mengfeng; Li, Dexin

    2011-01-01

    .... Vaccination with virus-like particles (VLPs) has shown considerable promise for many viral diseases, but the effect of DENV VLPs to induce specific immune responses has not been adequately investigated...

  18. Establishing cellular stress response profiles as biomarkers of homeodynamics, health, and hormesis

    OpenAIRE

    Demirovic, Dino; Rattan, Suresh

    2013-01-01

    Aging is the progressive shrinkage of the homeodynamic space. A crucial component of the homeodynamic space is the stress response (SR), by virtue of which a living system senses disturbance and initiates a series of events for maintenance, repair, adaptation, remodeling and survival. Here we discuss the main intracellular SR pathways in human cells, and argue for the need to define and establish the immediate and delayed stress response profiles (SRP) during aging. Such SRP are required to b...

  19. Tumor Necrosis Factor-α -and Interleukin-1-Induced Cellular Responses: Coupling Proteomic and Genomic Information

    OpenAIRE

    2007-01-01

    The pro-inflammatory cytokines, Tumor Necrosis Factor-alpha (TNFα) and Interleukin-1 (IL-1) mediate the innate immune response. Dysregulation of the innate immune response contributes to the pathogenesis of cancer, arthritis, and congestive heart failure. TNFα- and IL-1-induced changes in gene expression are mediated by similar transcription factors; however, TNFα and IL-1 receptor knock-out mice differ in their sensitivities to a known initiator (lipopolysaccharide, LPS) of the innate immune...

  20. Transcriptomal profiling of the cellular response to DNA damage mediated by Slug (Snai2)

    OpenAIRE

    Pérez-Caro, M.; Bermejo-Rodríguez, C.; González-Herrero, I; Sánchez-Beato, M; Piris, M. A.; Sánchez-García, I

    2008-01-01

    Snai2-deficient cells are radiosensitive to DNA damage. The function of Snai2 in response to DNA damage seems to be critical for its function in normal development and cancer. Here, we applied a functional genomics approach that combined gene-expression profiling and computational molecular network analysis to obtain global dissection of the Snai2-dependent transcriptional response to DNA damage in primary mouse embryonic fibroblasts (MEFs), which undergo p53-dependent growth arrest in respon...

  1. A biphasic endothelial stress-survival mechanism regulates the cellular response to vascular endothelial growth factor A

    Energy Technology Data Exchange (ETDEWEB)

    Latham, Antony M.; Odell, Adam F. [Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT (United Kingdom); Mughal, Nadeem A. [Leeds Vascular Institute, Leeds General Infirmary, Great George Street, Leeds LS1 3EX (United Kingdom); Issitt, Theo; Ulyatt, Clare; Walker, John H. [Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT (United Kingdom); Homer-Vanniasinkam, Shervanthi [Leeds Vascular Institute, Leeds General Infirmary, Great George Street, Leeds LS1 3EX (United Kingdom); Ponnambalam, Sreenivasan, E-mail: s.ponnambalam@leeds.ac.uk [Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2012-11-01

    Vascular endothelial growth factor A (VEGF-A) is an essential cytokine that regulates endothelial function and angiogenesis. VEGF-A binding to endothelial receptor tyrosine kinases such as VEGFR1 and VEGFR2 triggers cellular responses including survival, proliferation and new blood vessel sprouting. Increased levels of a soluble VEGFR1 splice variant (sFlt-1) correlate with endothelial dysfunction in pathologies such as pre-eclampsia; however the cellular mechanism(s) underlying the regulation and function of sFlt-1 are unclear. Here, we demonstrate the existence of a biphasic stress response in endothelial cells, using serum deprivation as a model of endothelial dysfunction. The early phase is characterized by a high VEGFR2:sFlt-1 ratio, which is reversed in the late phase. A functional consequence is a short-term increase in VEGF-A-stimulated intracellular signaling. In the late phase, sFlt-1 is secreted and deposited at the extracellular matrix. We hypothesized that under stress, increased endothelial sFlt-1 levels reduce VEGF-A bioavailability: VEGF-A treatment induces sFlt-1 expression at the cell surface and VEGF-A silencing inhibits sFlt-1 anchorage to the extracellular matrix. Treatment with recombinant sFlt-1 inhibits VEGF-A-stimulated in vitro angiogenesis and sFlt-1 silencing enhances this process. In this response, increased VEGFR2 levels are regulated by the phosphatidylinositol-3-kinase and PKB/Akt signaling pathways and increased sFlt-1 levels by the ERK1/2 signaling pathway. We conclude that during serum withdrawal, cellular sensing of environmental stress modulates sFlt-1 and VEGFR2 levels, regulating VEGF-A bioavailability and ensuring cell survival takes precedence over cell proliferation and migration. These findings may underpin an important mechanism contributing to endothelial dysfunction in pathological states. -- Highlights: Black-Right-Pointing-Pointer Endothelial cells mount a stress response under conditions of low serum. Black

  2. Cellular responses to chlorin-based photosensitizer DH-II-24 under darkness in human gastric adenocarcinoma AGS cells.

    Science.gov (United States)

    Lim, Young-Cheol; Yoo, Je-Ok; Kang, Seong-Sik; Kim, Young-Myeong; Ha, Kwon-Soo

    2011-03-01

    We investigated cellular responses to chlorin-based photosensitizer DH-II-24 under darkness in human gastric adenocarcinoma AGS cells. Cells were loaded with 0.5-10 μg/mL DH-II-24 for 12 h, and intracellular reactive oxygen species (ROS) and intracellular Ca(2+) levels, in situ tissue transglutaminase (tTGase) activity, cell viability, cell morphology and cell cycle were examined. DH-II-24 treatment had no effect on intracellular ROS production or cell morphology, and did not induce cell detachment at any concentrations tested. In addition, cell viability and cell cycle progression were not altered by the photosensitizer. However, DH-II-24 treatment elevated the basal level of intracellular Ca(2+) in a dose-dependent manner and inhibited tTGase activity without affecting tTGase expression levels. Furthermore, DH-II-24 inhibited lysophosphatidic acid-induced activation of tTGase in a dose-dependent manner. In contrast, photodynamic therapy (PDT) with 1 μg/mL DH-II-24 significantly elevated intracellular ROS and in situ tTGase activity in parallel with a rapid and large increase in intracellular Ca(2+) levels. DH-II-24-mediated PDT decreased cell viability and induced cell detachment. These results demonstrate that DH-II-24 treatment alone under darkness induced different cellular responses to DH-II-24-mediated PDT.

  3. Tetanus toxoid-loaded layer-by-layer nanoassemblies for efficient systemic, mucosal, and cellular immunostimulatory response following oral administration.

    Science.gov (United States)

    Harde, Harshad; Agrawal, Ashish Kumar; Jain, Sanyog

    2015-10-01

    The present study reports the tetanus toxoid (TT)-loaded layer-by-layer nanoassemblies (layersomes) with enhanced protection, permeation, and presentation for comprehensive oral immunization. The stable and lyophilized TT-loaded layersomes were prepared by a thin-film hydration method followed by alternate layer-by-layer coating of an electrolyte. The developed system was assessed for in vitro stability of antigen and formulation, cellular uptake, ex vivo intestinal uptake, and immunostimulatory response using a suitable experimental protocol. Layersomes improved the stability in simulated biological media as well as protected the integrity/conformation and native 3D structure of TT as confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), circular dichroism (CD), and fluorescence spectroscopy, respectively. The cell culture studies demonstrated a 3.8-fold higher permeation of layersomes in Caco-2 cells and an 8.5-fold higher uptake by antigen-presenting cells (RAW 264.7). The TT-loaded layersomes elicited a complete immunostimulatory profile consisting of higher systemic (serum IgG titer), mucosal (sIgA titer), and cellular (interleukin-2 (IL-2) and interferon-γ (IFN-γ) levels) immune response after peroral administration in mice. The modified TT inhibition assay further confirmed the elicitation of complete protective levels of anti-TT antibody (>0.1 IU/mL) by layersomes. In conclusion, the proposed strategy is expected to contribute significantly in the field of stable liposome technology for mass immunization through the oral route.

  4. A possible role for extra-cellular ATP in plant responses to high frequency, low amplitude electromagnetic field.

    Science.gov (United States)

    Roux, David; Faure, Catherine; Bonnet, Pierre; Girard, Sébastien; Ledoigt, Gérard; Davies, Eric; Gendraud, Michel; Paladian, Françoise; Vian, Alain

    2008-06-01

    In parallel to evoking the accumulation of stress-related transcripts, exposure to low level 900 MHz EMF affected the levels of ATP, the main energy molecule of the cell. Its concentration dropped rapidly (27% after 30 min) in response to EMF exposure, along with a 18% decrease in the adenylate energy charge (AEC), a good marker of cell energy status. One could interpret this decrease in ATP and AEC in a classical way, i.e., as the result of an increase in cellular energy usage, but recent work brings exciting new insights in pointing out a signalling function for ATP, especially in the stress physiology context where it could trigger both reactive oxygen species and calcium movement (this latter being involved in plant responses to EMF exposure). In this addendum, we discuss our results within this new perspective for ATP function.

  5. Blood Group O-Dependent Cellular Responses to Cholera Toxin: Parallel Clinical and Epidemiological Links to Severe Cholera.

    Science.gov (United States)

    Kuhlmann, F Matthew; Santhanam, Srikanth; Kumar, Pardeep; Luo, Qingwei; Ciorba, Matthew A; Fleckenstein, James M

    2016-08-03

    Because O blood group has been associated with more severe cholera infections, it has been hypothesized that cholera toxin (CT) may bind non-O blood group antigens of the intestinal mucosae, thereby preventing efficient interaction with target GM1 gangliosides required for uptake of the toxin and activation of cyclic adenosine monophosphate (cAMP) signaling in target epithelia. Herein, we show that after exposure to CT, human enteroids expressing O blood group exhibited marked increase in cAMP relative to cells derived from blood group A individuals. Likewise, using CRISPR/Cas9 engineering, a functional group O line (HT-29-A(-/-)) was generated from a parent group A HT-29 line. CT stimulated robust cAMP responses in HT-29-A(-/-) cells relative to HT-29 cells. These findings provide a direct molecular link between blood group O expression and differential cellular responses to CT, recapitulating clinical and epidemiologic observations.

  6. High cortisol awakening response is associated with impaired error monitoring and decreased post-error adjustment.

    Science.gov (United States)

    Zhang, Liang; Duan, Hongxia; Qin, Shaozheng; Yuan, Yiran; Buchanan, Tony W; Zhang, Kan; Wu, Jianhui

    2015-01-01

    The cortisol awakening response (CAR), a rapid increase in cortisol levels following morning awakening, is an important aspect of hypothalamic-pituitary-adrenocortical axis activity. Alterations in the CAR have been linked to a variety of mental disorders and cognitive function. However, little is known regarding the relationship between the CAR and error processing, a phenomenon that is vital for cognitive control and behavioral adaptation. Using high-temporal resolution measures of event-related potentials (ERPs) combined with behavioral assessment of error processing, we investigated whether and how the CAR is associated with two key components of error processing: error detection and subsequent behavioral adjustment. Sixty university students performed a Go/No-go task while their ERPs were recorded. Saliva samples were collected at 0, 15, 30 and 60 min after awakening on the two consecutive days following ERP data collection. The results showed that a higher CAR was associated with slowed latency of the error-related negativity (ERN) and a higher post-error miss rate. The CAR was not associated with other behavioral measures such as the false alarm rate and the post-correct miss rate. These findings suggest that high CAR is a biological factor linked to impairments of multiple steps of error processing in healthy populations, specifically, the automatic detection of error and post-error behavioral adjustment. A common underlying neural mechanism of physiological and cognitive control may be crucial for engaging in both CAR and error processing.

  7. Developmental programming in response to intrauterine growth restriction impairs myoblast function and skeletal muscle metabolism.

    Science.gov (United States)

    Yates, D T; Macko, A R; Nearing, M; Chen, X; Rhoads, R P; Limesand, S W

    2012-01-01

    Fetal adaptations to placental insufficiency alter postnatal metabolic homeostasis in skeletal muscle by reducing glucose oxidation rates, impairing insulin action, and lowering the proportion of oxidative fibers. In animal models of intrauterine growth restriction (IUGR), skeletal muscle fibers have less myonuclei at birth. This means that myoblasts, the sole source for myonuclei accumulation in fibers, are compromised. Fetal hypoglycemia and hypoxemia are complications that result from placental insufficiency. Hypoxemia elevates circulating catecholamines, and chronic hypercatecholaminemia has been shown to reduce fetal muscle development and growth. We have found evidence for adaptations in adrenergic receptor expression profiles in myoblasts and skeletal muscle of IUGR sheep fetuses with placental insufficiency. The relationship of β-adrenergic receptors shifts in IUGR fetuses because Adrβ2 expression levels decline and Adrβ1 expression levels are unaffected in myofibers and increased in myoblasts. This adaptive response would suppress insulin signaling, myoblast incorporation, fiber hypertrophy, and glucose oxidation. Furthermore, this β-adrenergic receptor expression profile persists for at least the first month in IUGR lambs and lowers their fatty acid mobilization. Developmental programming of skeletal muscle adrenergic receptors partially explains metabolic and endocrine differences in IUGR offspring, and the impact on metabolism may result in differential nutrient utilization.

  8. Developmental Programming in Response to Intrauterine Growth Restriction Impairs Myoblast Function and Skeletal Muscle Metabolism

    Directory of Open Access Journals (Sweden)

    D. T. Yates

    2012-01-01

    Full Text Available Fetal adaptations to placental insufficiency alter postnatal metabolic homeostasis in skeletal muscle by reducing glucose oxidation rates, impairing insulin action, and lowering the proportion of oxidative fibers. In animal models of intrauterine growth restriction (IUGR, skeletal muscle fibers have less myonuclei at birth. This means that myoblasts, the sole source for myonuclei accumulation in fibers, are compromised. Fetal hypoglycemia and hypoxemia are complications that result from placental insufficiency. Hypoxemia elevates circulating catecholamines, and chronic hypercatecholaminemia has been shown to reduce fetal muscle development and growth. We have found evidence for adaptations in adrenergic receptor expression profiles in myoblasts and skeletal muscle of IUGR sheep fetuses with placental insufficiency. The relationship of β-adrenergic receptors shifts in IUGR fetuses because Adrβ2 expression levels decline and Adrβ1 expression levels are unaffected in myofibers and increased in myoblasts. This adaptive response would suppress insulin signaling, myoblast incorporation, fiber hypertrophy, and glucose oxidation. Furthermore, this β-adrenergic receptor expression profile persists for at least the first month in IUGR lambs and lowers their fatty acid mobilization. Developmental programming of skeletal muscle adrenergic receptors partially explains metabolic and endocrine differences in IUGR offspring, and the impact on metabolism may result in differential nutrient utilization.

  9. Nitric oxide synthase inhibitor, aminoguanidine reduces intracerebroventricular colchicine induced neurodegeneration, memory impairments and changes of systemic immune responses in rats.

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    Sil, Susmita; Ghosh, Tusharkanti; Ghosh, Rupsa; Gupta, Pritha

    2017-02-15

    Intracerebroventricular (i.c.v.) injection of colchicine induces neurodegeneration, memory impairments and changes of some systemic immune responses in rats. Though the role of cox 2 in these colchicine induced changes have been evaluated, the influence of nitric oxide synthase (NOS) remains to be studied. The present study was designed to assess the role of NOS on the i.c.v. colchicine induced neurodegeneration, memory impairments and changes of some systemic immune responses by inhibiting its activity with aminoguanidine. In the present study the impairments of working and reference memories, neurodegeneration (chromatolysis and plaque formation) and changes of neuroinflammatory markers in the hippocampus (increased TNF α, IL 1β, ROS and nitrite) along with changes of serum inflammatory markers (TNF α, IL 1β, ROS and nitrite) and alteration of systemic immune responses (higher phagocytic activity of blood WBC and splenic PMN, higher cytotoxicity and lower leukocyte adhesion inhibition index of splenic MNC) were measured in the intracerebroventricular colchicine injected rats (ICIR). Administration of aminoguanidine (p.o. 30/50mg/kg body weight) to ICIR resulted in recovery of neuroinflammation and partial prevention of neurodegeneration which could be corroborated with the partial recovery of memory impairments in this model. The recovery of serum inflammatory markers and the systemic immune responses in ICIR was also observed after administration of aminoguanidine. Therefore, the present study shows that aminoguanidine can protect the colchicine induced neurodegeneration, memory impairments, and changes of systemic immune systemic responses in ICIR by inhibiting the iNOS. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Alcohol-induced impairment of inhibitory control is linked to attenuated brain responses in right fronto-temporal cortex

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    Gan, Gabriela; Guevara, Alvaro; Marxen, Michael; Neumann, Maike; Jünger, Elisabeth; Kobiella, Andrea; Mennigen, Eva; Pilhatsch, Maximilian; Schwarz, Daniel; Zimmermann, Ulrich S.; Smolka, Michael N.

    2014-01-01

    Background A self-enhancing loop between impaired inhibitory control under alcohol and alcohol consumption has been proposed as a possible mechanism underlying dysfunctional drinking in susceptible people. However, the neural underpinnings of alcohol-induced impairment of inhibitory control are widely unknown. Methods We measured inhibitory control in fifty young adults with a stop-signal task (SST) during functional magnetic resonance imaging (fMRI). In a single-blind placebo-controlled cross-over design, all participants performed the SST once under alcohol with a breath alcohol concentration (BrAC) of 0.6 g/kg, and once under placebo. In addition, alcohol consumption was assessed using a free-access alcohol self-administration (ASA) paradigm in the same participants. Results Inhibitory control was robustly decreased under alcohol compared to placebo indicated by longer stop-signal reaction times (SSRTs). On the neural level, impaired inhibitory control under alcohol was associated with attenuated brain responses in the right fronto-temporal portion of the inhibition network that supports the attentional capture of infrequent stop-signals, and subsequent updating of action plans from response execution to inhibition. Furthermore, the extent of alcohol-induced impairment of inhibitory control predicted free-access alcohol consumption. Conclusion We suggest that during inhibitory control alcohol affects cognitive processes preceding actual motor inhibition. Under alcohol, decreased brain responses in right fronto-temporal areas might slow down the attentional capture of infrequent stop-signals and subsequent updating of action plans which leads to impaired inhibitory control. In turn, pronounced alcohol-induced impairment of inhibitory control may enhance alcohol consumption in young adults which might promote future alcohol problems. PMID:24560581

  11. Alcohol-induced impairment of inhibitory control is linked to attenuated brain responses in right fronto-temporal cortex.

    Science.gov (United States)

    Gan, Gabriela; Guevara, Alvaro; Marxen, Michael; Neumann, Maike; Jünger, Elisabeth; Kobiella, Andrea; Mennigen, Eva; Pilhatsch, Maximilian; Schwarz, Daniel; Zimmermann, Ulrich S; Smolka, Michael N

    2014-11-01

    A self-enhancing loop between impaired inhibitory control under alcohol and alcohol consumption has been proposed as a possible mechanism underlying dysfunctional drinking in susceptible people. However, the neural underpinnings of alcohol-induced impairment of inhibitory control are widely unknown. We measured inhibitory control in 50 young adults with a stop-signal task during functional magnetic resonance imaging. In a single-blind placebo-controlled cross-over design, all participants performed the stop-signal task once under alcohol with a breath alcohol concentration of .6 g/kg and once under placebo. In addition, alcohol consumption was assessed with a free-access alcohol self-administration paradigm in the same participants. Inhibitory control was robustly decreased under alcohol compared with placebo, indicated by longer stop-signal reaction times. On the neural level, impaired inhibitory control under alcohol was associated with attenuated brain responses in the right fronto-temporal portion of the inhibition network that supports the attentional capture of infrequent stop-signals and subsequent updating of action plans from response execution to inhibition. Furthermore, the extent of alcohol-induced impairment of inhibitory control predicted free-access alcohol consumption. We suggest that during inhibitory control alcohol affects cognitive processes preceding actual motor inhibition. Under alcohol, decreased brain responses in right fronto-temporal areas might slow down the attentional capture of infrequent stop-signals and subsequent updating of action plans, which leads to impaired inhibitory control. In turn, pronounced alcohol-induced impairment of inhibitory control might enhance alcohol consumption in young adults, which might promote future alcohol problems. Copyright © 2014 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  12. OSTEOPOROSIS AND ALZHEIMER PATHOLOGY: ROLE OF CELLULAR STRESS RESPONSE AND HORMETIC REDOX SIGNALING IN AGING AND BONE REMODELING

    Directory of Open Access Journals (Sweden)

    Vittorio eCalabrese

    2014-06-01

    Full Text Available Alzheimer’s disease (AD as well as osteoporosis are multifactorial progressive degenerative disorders characterized by low parenchymal density and microarchitectural deterioration of tissue. Though not referred to as one of the major complications of AD, osteoporosis and hip fracture are commonly observed in patients with AD, however, the mechanisms underlying this association remain poorly understood. Reactive oxygen species (ROS are generally recognized as intracellular redox signaling molecules involved in the regulation of bone metabolism, including receptor activator of nuclear factor-kB ligand (RANKL-dependent osteoclast differentiation, but they also have cytotoxic effects that include peroxidation of lipids and oxidative damage to proteins and DNA. ROS formation, which is positively implicated in cellular stress response mechanisms, is a highly regulated process controlled by a complex network of intracellular signaling pathways which regulate life span across species including vitagenes which are genes involved in preserving cellular homeostasis during stressful conditions. Vitagenes encode for heat shock proteins (Hsp Hsp32, Hsp70, the thioredoxin and the sirtuin protein systems. Dietary antioxidants, have recently been demonstrated to be neuroprotective through the activation of hormetic pathways, including vitagenes. The hormetic dose–response, has the potential to affect significantly the design of pre-clinical studies and clinical trials as well as strategies for optimal patient dosing in the treatment of numerous diseases. Given the broad cytoprotective properties of the heat shock response there is now strong interest in discovering and developing pharmacological agents capable of inducing stress responses. Here we focus on possible signaling mechanisms involved in bone remodeling and activation of vitagenes resulting in enhanced defense against energy and stress resistance homeostasis dysruption with consequent impact on

  13. Design and synthesis of temperature-responsive polymer/silica hybrid nanoparticles and application to thermally controlled cellular uptake.

    Science.gov (United States)

    Hiruta, Yuki; Nemoto, Ryo; Kanazawa, Hideko

    2017-05-01

    This study reports the development of temperature-responsive polymer/silica hybrid nanoparticles and their application to temperature-dependent intracellular uptake of hydrophobic encapsulated fluorescence molecules. Amphiphilic diblock copolymer comprising a temperature-responsive segment, poly(N-isopropylacrylamide-co-N,N-dimethylacrylamide) [P(NIPAAm-co-DMAAm)] and a trimethyoxysilyl-containing hydrophobic segment was synthesized (PBM-b-ND); this amphiphilic diblock copolymer self-assembled in an aqueous solution, and temperature-responsive polymer/silica hybrid fluorescence nanoparticles were fabricated via a base-catalyzed sol-gel process. The fluorescence probe rhodamine DHPE or boron dipyrromethene derivative was encapsulated into the polymer core with a silica network in a stable manner. Other types of polymer/silica hybrid fluorescence nanoparticles were also developed using either homo-PNIPAAm (PBM-b-N) or homo-PDMAAm (PBM-b-D) segments, instead of P(NIPAAm-co-DMAAm). While PBM-b-D did not exhibit a temperature-dependent phase transition (hydrophilic characteristic), PBM-b-N and PBM-b-ND exhibited temperature-dependent phase transition (hydrophilic/hydrophobic) at 32°C and 38°C, respectively. The cellular uptake of PBM-b-N was clearly observed at both 37°C and 42°C, while the cellular uptake of PBM-b-D was minimal at these temperatures. On the other hand, significant enhancement in the intracellular uptake of PBM-b-ND was observed at 42°C, compared to its uptake at a lower temperature of 37°C. These results indicated that temperature-responsive polymer/silica hybrid nanoparticle, PBM-b-ND demonstrate potential for applications in theranostics with cancer the