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Sample records for cellular responses induced

  1. Hyaluronic Acid Inhibits Polycation Induced Cellular Responses

    OpenAIRE

    lalenti, A.; Lanaro, A.; Brignola, G.; Marotta, P; Di Rosa, M.

    1994-01-01

    Positively charged macromolecules cause a variety of pathological events through their electrostatic interaction with anionic sites present on the membrane of target cells. In the present study we have investigated the effect of hyaluronic acid, a negatively charged molecule, on rat paw oedema induced by poly-L-lysine as well as on histamine release from rat mast cells and nitric oxide formation from rabbit aorta, both induced by this polycation. The results indicate that hyaluronic acid is a...

  2. 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.

  3. Ethanol Cellular Defense Induce Unfolded Protein Response in Yeast.

    Science.gov (United States)

    Navarro-Tapia, Elisabet; Nana, Rebeca K; Querol, Amparo; Pérez-Torrado, Roberto

    2016-01-01

    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 S. 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, our data suggest that there

  4. 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

  5. Nonlinear dose-response relationships and inducible cellular defence mechanisms

    International Nuclear Information System (INIS)

    With the inclusion of inducible radioprotective mechanisms in a radiobiological state-vector model it was possible to explain plateaus in dose-response relationships for neoplastic transformation produced by in vitro irradiation of different cell lines with low-LET irradiation at high dose rates. The current study repeated the simulation of one data set that contains a plateau at mid doses. In contrast to earlier studies, the new one did not model the repair of double-strand breaks (DSBs) located in bulk DNA (likely via non-homologous end joining) as being inducible. Repair of specific DSBs located in actively transcribed genes was assumed to occur via homologous recombination and was considered to be inducible. This reduced the number of parameters that have to be determined by fitting the model to data. In addition, all types of radical scavengers were formerly considered to be inducible by radiation. This was redefined in the current work and the effectiveness of scavengers was implemented in a refined way. The current work investigated whether these and other model adjustments lead to an improved fit of the data set. (author)

  6. Study on cellular survival adaptive response induced by low dose irradiation of 153Sm

    International Nuclear Information System (INIS)

    The present study engages in determining whether low dose irradiation of 153Sm could cut down the responsiveness of cellular survival to subsequent high dose exposure of 153Sm so as to make an inquiry into approach the protective action of adaptive response by second irradiation of 153Sm. Experimental results indicate that for inductive low dose of radionuclide 153Sm 3.7 kBq/ml irradiated beforehand to cells has obvious resistant effect in succession after high dose irradiation of 153Sm 3.7 x 102 kBq/ml was observed. Cells exposed to low dose irradiation of 153Sm become adapted and therefore the subsequent cellular survival rate induced by high dose of 153Sm is sufficiently higher than high dose of 153Sm merely. It is evident that cellular survival adaptive response could be induced by pure low dose irradiation of 153Sm only

  7. 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

  8. Cellular Response to Bleomycin-Induced DNA Damage in Human Fibroblast Cells in Space

    Science.gov (United States)

    Lu, Tao; Zhang, Ye; Wong, Michael; Stodieck, Louis; Karouia, Fathi; Wu, Honglu

    2015-01-01

    Outside the protection of the geomagnetic field, astronauts and other living organisms are constantly exposed to space radiation that consists of energetic protons and other heavier charged particles. Whether spaceflight factors, microgravity in particular, have effects on cellular responses to DNA damage induced by exposure to radiation or cytotoxic chemicals is still unknown, as is their impact on the radiation risks for astronauts and on the mutation rate in microorganisms. Although possible synergistic effects of space radiation and other spaceflight factors have been investigated since the early days of the human space program, the published results were mostly conflicting and inconsistent. To investigate effects of spaceflight on cellular responses to DNA damages, human fibroblast cells flown to 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) similar to the ionizing radiation. Damages in the DNA were measured by the phosphorylation of a histone protein H2AX (g-H2AX), which showed slightly more foci in the cells on ISS than in the ground control. The expression of genes involved in DNA damage response was also analyzed using the PCR array. Although a number of the genes, including CDKN1A and PCNA, were significantly altered in the cells after bleomycin treatment, no significant difference in the expression profile of DNA damage response genes was found between the flight and ground samples. At the time of the bleomycin treatment, the cells on the ISS were found to be proliferating faster than the ground control as measured by the percentage of cells containing positive Ki-67 signals. Our results suggested that the difference in g-H2AX focus counts between flight and ground was due to the faster growth rate of the cells in space, but spaceflight did not affect initial transcriptional responses of the DNA damage response genes to

  9. 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.

  10. 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

    2012-12-01

    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 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. PMID:22915633

  11. Exposure to low infective doses of HCV induces cellular immune responses without consistently detectable viremia or seroconversion in chimpanzees

    International Nuclear Information System (INIS)

    In hepatitis C virus (HCV) infection, there is accumulating data suggesting the presence of cellular immune responses to HCV in exposed but seemingly uninfected populations. Some studies have suggested cross-reactive antigens rather than prior HCV exposure as the main reason for the immune responses. In this study we address this question by analyzing the immune response of chimpanzees that have been sequentially exposed to increasing doses of HCV virions. The level of viremia, as well as the immune responses to HCV at different times after virus inoculation, were examined. Our data indicate that HCV infective doses as low as 1-10 RNA (+) virions induce detectable cellular immune responses in chimpanzees without consistently detectable viremia or persistent seroconversion. However, increasing the infective doses of HCV to 100 RNA (+) virions overcame the low-inoculum-induced immune response and produced high-level viremia followed by seroconversion

  12. Posintro™-HBsAg, a modified ISCOM including HBsAg, induces strong cellular and humoral responses

    DEFF Research Database (Denmark)

    Schiött, Asa; Larsson, Kristina; Manniche, Søren;

    2011-01-01

    HBsAg vaccine formulation, Posintro™-HBsAg, was compared to two commercial hepatitis B vaccines including aluminium or monophosphoryl lipid A (MPL) and the two adjuvant systems MF59 and QS21 in their efficiency to prime both cellular and humoral immune responses. The Posintro™-HBsAg induced...

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

    OpenAIRE

    E.B Dolan; 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 ...

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

    OpenAIRE

    Zhang Quanfu; Zhang Fushun; Zhang Li; Jin Cong; Wang Xiaofang; Miao Fang; Li Chuan; Gu Wen; Liang Mifang; Zhang Shuo; Jiang Lifang; Li Mengfeng; Li Dexin

    2011-01-01

    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...

  15. Staphylococcus aureus avirulent mutant vaccine induces humoral and cellular immune responses on pregnant heifers.

    Science.gov (United States)

    Pellegrino, M; Rodriguez, N; Vivas, A; Giraudo, J; Bogni, C

    2016-06-17

    Bovine mastitis produces economic losses, attributable to the decrease in milk production, reduced milk quality, costs of treatment and replacement of animals. A successful prophylactic vaccine against Staphylococcus aureus should elicit both humoral and cellular immune responses. In a previous report we evaluated the effectiveness of a live vaccine to protect heifers against challenge with a virulent strain. In the present study the immunological response of heifers after combined immunization schedule was investigated. In a first experimental trial, heifers were vaccinated with 3 subcutaneous doses of avirulent mutant S. aureus RC122 before calving and one intramammary dose (IMD) after calving. Antibodies concentration in blood, bactericidal effect of serum from vaccinated animals and lymphocyte proliferation was determined. The levels of total IgG, IgG1 and IgG2 in colostrum and the lymphocyte proliferation index were significantly higher in vaccinated respect to non-vaccinated group throughout the experiment. The second trial, where animals were inoculated with different vaccination schedules, was carried out to determine the effect of the IMD on the level of antibodies in blood and milk, cytokines (IL-13 and IFN-γ) concentration and milk's SCC and bacteriology. The bacterial growth of the S. aureus strains was totally inhibited at 1-3×10(6) and 1-3×10(3)cfu/ml, when the strains were mixed with pooled serum diluted 1/40. The results shown that IMD has not a significant effect on the features determinate. In conclusion, a vaccination schedule involving three SC doses before calving would be enough to stimulate antibodies production in milk without an IMD. Furthermore, the results showed a bactericidal effect of serum from vaccinated animals and this provides further evidence about serum functionality. Immune responses, humoral (antigen-specific antibodies and Th2 type cytokines) and cellular (T-lymphocyte proliferation responses and Th1 type cytokines), were

  16. Hemin activation of innate cellular response blocks human immunodeficiency virus type-1-induced osteoclastogenesis

    International Nuclear Information System (INIS)

    The normal skeletal developmental and homeostatic process termed osteoclastogenesis is exacerbated in numerous pathological conditions and causes excess bone loss. In cancer and HIV-1-infected patients, this disruption of homeostasis results in osteopenia and eventual osteoporesis. Counteracting the factors responsible for these metabolic disorders remains a challenge for preventing or minimizing this co-morbidity associated with these diseases. In this report, we demonstrate that a hemin-induced host protection mechanism not only suppresses HIV-1 associated osteoclastogenesis, but it also exhibits anti-osteoclastogenic activity for non-infected cells. Since the mode of action of hemin is both physiological and pharmacological through induction of heme oxygenase-1 (HO-1), an endogenous host protective response to an FDA-licensed therapeutic used to treat another disease, our study suggests an approach to developing novel, safe and effective therapeutic strategies for treating bone disorders, because hemin administration in humans has previously met required FDA safety standards. - Highlights: • HIV-1 infection induced osteoclastogenesis in primary human macrophages. • Heme oxygenase-1 (HO-1) induction inhibited HIV-1-induced osteoclastogenesis in macrophages. • HO-1 induction suppressed RANKL-enhanced osteoclastogenesis in HIV-1-infected macrophages. • This inverse relationship between HO-1 and HIV-1 pathogenesis may define a novel host defense response against HIV-1 infection

  17. Hemin activation of innate cellular response blocks human immunodeficiency virus type-1-induced osteoclastogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Kazuyo [Microscopy and Imaging Core Facility, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD (United States); Adhikari, Rewati [Division of Transfusion Transmitted Diseases, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD (United States); Yamada, Kenneth M. [National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Dhawan, Subhash, E-mail: subhash.dhawan@fda.hhs.gov [Division of Transfusion Transmitted Diseases, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD (United States)

    2015-08-14

    The normal skeletal developmental and homeostatic process termed osteoclastogenesis is exacerbated in numerous pathological conditions and causes excess bone loss. In cancer and HIV-1-infected patients, this disruption of homeostasis results in osteopenia and eventual osteoporesis. Counteracting the factors responsible for these metabolic disorders remains a challenge for preventing or minimizing this co-morbidity associated with these diseases. In this report, we demonstrate that a hemin-induced host protection mechanism not only suppresses HIV-1 associated osteoclastogenesis, but it also exhibits anti-osteoclastogenic activity for non-infected cells. Since the mode of action of hemin is both physiological and pharmacological through induction of heme oxygenase-1 (HO-1), an endogenous host protective response to an FDA-licensed therapeutic used to treat another disease, our study suggests an approach to developing novel, safe and effective therapeutic strategies for treating bone disorders, because hemin administration in humans has previously met required FDA safety standards. - Highlights: • HIV-1 infection induced osteoclastogenesis in primary human macrophages. • Heme oxygenase-1 (HO-1) induction inhibited HIV-1-induced osteoclastogenesis in macrophages. • HO-1 induction suppressed RANKL-enhanced osteoclastogenesis in HIV-1-infected macrophages. • This inverse relationship between HO-1 and HIV-1 pathogenesis may define a novel host defense response against HIV-1 infection.

  18. 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

  19. 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. PMID:26865595

  20. Mycoplasma hyopneumoniae and Mycoplasma flocculare differential domains from orthologous surface proteins induce distinct cellular immune responses in mice.

    Science.gov (United States)

    Leal, Fernanda Munhoz Dos Anjos; Virginio, Veridiana Gomes; Martello, Carolina Lumertz; Paes, Jéssica Andrade; Borges, Thiago J; Jaeger, Natália; Bonorino, Cristina; Ferreira, Henrique Bunselmeyer

    2016-07-15

    Mycoplasma hyopneumoniae and Mycoplasma flocculare are two genetically close species found in the swine respiratory tract. Despite their similarities, while M. hyopneumoniae is the causative agent of porcine enzootic pneumonia, M. flocculare is a commensal bacterium. Genomic and transcriptional comparative analyses so far failed to explain the difference in pathogenicity between these two species. We then hypothesized that such difference might be, at least in part, explained by amino acid sequence and immunological or functional differences between ortholog surface proteins. In line with that, it was verified that approximately 85% of the ortholog surface proteins from M. hyopneumoniae 7448 and M. flocculare present one or more differential domains. To experimentally assess possible immunological implications of this kind of difference, the extracellular differential domains from one pair of orthologous surface proteins (MHP7448_0612, from M. hyopneumoniae, and MF_00357, from M. flocculare) were expressed in E. coli and used to immunize mice. The recombinant polypeptides (rMHP61267-169 and rMF35767-196, respectively) induced distinct cellular immune responses. While, rMHP61267-169 induced both Th1 and Th2 responses, rMF35767-196 induced just an early pro-inflammatory response. These results indicate that immunological properties determined by differential domains in orthologous surface protein might play a role in pathogenicity, contributing to elicit specific and differential immune responses against each species. PMID:27283856

  1. 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

  2. Dengue encephalitis-associated immunopathology in the mouse model: Implications for vaccine developers and antigens inducer of cellular immune response.

    Science.gov (United States)

    Marcos, Ernesto; Lazo, Laura; Gil, Lázaro; Izquierdo, Alienys; Suzarte, Edith; Valdés, Iris; Blanco, Aracelys; Ancizar, Julio; Alba, José Suárez; Pérez, Yusleydis de la C; Cobas, Karen; Romero, Yaremis; Guillén, Gerardo; Guzmán, María G; Hermida, Lisset

    2016-08-01

    Despite the many efforts made by the scientific community in the development of vaccine candidates against dengue virus (DENV), no vaccine has been licensed up to date. Although the immunopathogenesis associated to the disease is a key factor to take into account by vaccine developers, the lack of animal models that reproduce the clinical signs of the disease has hampered the vaccine progress. Non-human primates support viral replication, but they are very expensive and do not show signs of disease. Immunocompromised mice develop viremia and some signs of the disease; however, they are not valuable for vaccine testing. Nowadays, immunocompetent mice are the most used model to evaluate the immunogenicity of vaccine candidates. These animals are resistant to DENV infection; therefore, the intracranial inoculation with neuroadapted virus, which provokes viral encephalitis, represents an alternative to evaluate the protective capacity of vaccine candidates. Previous results have demonstrated the crucial role of cellular immune response in the protection induced by the virus and vaccine candidates in this mouse encephalitis model. However, in the present work we are proposing that the magnitude of the cell-mediated immunity and the inflammatory response generated by the vaccine can modulate the survival rate after viral challenge. We observed that the intracranial challenge of naïve mice with DENV-2 induces the recruitment of immune cells that contribute to the reduction of viral load, but does not increase the survival rate. On the contrary, animals treated with cyclophosphamide, an immunosuppressive drug that affects proliferating lymphocytes, had a higher viral load but a better survival rate than untreated animals. These results suggest that the immune system is playing an immunopathogenic role in this model and the survival rate may not be a suitable endpoint in the evaluation of vaccine candidates based on antigens that induce a strong cellular immune response

  3. Lentiviral vector encoding ubiquitinated hepatitis B core antigen induces potent cellular immune responses and therapeutic immunity in HBV transgenic mice.

    Science.gov (United States)

    Dai, Shenglan; Zhuo, Meng; Song, Linlin; Chen, Xiaohua; Yu, Yongsheng; Zang, Guoqing; Tang, Zhenghao

    2016-07-01

    Predominant T helper cell type 1 (Th1) immune responses accompanied by boosted HBV-specific cytotoxic T lymphocyte (CTL) activity are essential for the clearance of hepatitis B virus (HBV) in chronic hepatitis B (CHB) patients. Ubiquitin (Ub) serves as a signal for the target protein to be recognized and degraded through the ubiquitin-proteasome system (UPS). Ubiquitinated hepatitis B core antigen (Ub-HBcAg) has been proved to be efficiently degraded into the peptides, which can be presented by major histocompatibility complex (MHC) class I resulting in stimulating cell-mediated responses. In the present study, lentiviral vectors encoding Ub-HBcAg (LV-Ub-HBcAg) were designed and constructed as a therapeutic vaccine for immunotherapy. HBcAg-specific cellular immune responses and anti-viral effects induced by LV-Ub-HBcAg were evaluated in HBV transgenic mice. We demonstrated that immunization with LV-Ub-HBcAg promoted the secretion of cytokines interleukin-2 (IL-2), interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α), generated remarkably high percentages of IFN-γ-secreting CD8(+) T cells and CD4(+) T cells, and enhanced HBcAg-specific CTL activity in HBV transgenic mice. More importantly, vaccination with LV-Ub-HBcAg could efficiently decreased the levels of serum hepatitis B surface antigen (HBsAg), HBV DNA and the expression of HBsAg and HBcAg in liver tissues of HBV transgenic mice. In addition, LV-Ub-HBcAg could upregulate the expression of T cell-specific T-box transcription factor (T-bet) and downregulate the expression of GATA-binding protein 3 (GATA-3) in spleen T lymphocytes. The therapeutic vaccine LV-Ub-HBcAg could break immune tolerance, and induce potent HBcAg specific cellular immune responses and therapeutic effects in HBV transgenic mice. PMID:26874581

  4. Effects of Spaceflight on Molecular and Cellular Responses to Bleomycin-induced DNA Damages in Confluent Human Fibroblasts

    Science.gov (United States)

    Lu, Tao; Wu, Honglu; Karouia, Fathi; Stodieck, Louis; Zhang, Ye; Wong, Michael

    2016-07-01

    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 mg/ml bleomycin for 3 hours, cells were fixed for immunofluorescence assays and for RNA preparation. Extents of DNA damages were quantified by focus pattern and focus number counting of phosphorylated histone protein H2AX (γg-H2AX). The cells on the ISS showed modestly increased average focus 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 profiles 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 γg-H2AX focus counts between flight and ground was due to the higher percentage of proliferating cells in space, but spaceflight did not

  5. THE HUMORAL AND CELLULAR IMMUNE RESPONSES INDUCED BY HPV18L1-E6/E7 DNA VACCINES IN MICE

    Institute of Scientific and Technical Information of China (English)

    Yang Jin; Li Xu; Li Ang; Wang Yili; Si Lüsheng

    2006-01-01

    Objective To construct eukaryotic expression vector of HPV18 L1- E6, E7 chimeric gene and examine the humoral and cellular immune responses induced by this DNA vaccines in mice. Methods The C-terminal of major capsid protein L1 gene and mutant zinc finger domains of early E6/7 oncogenes in HPV18 were integrated and inserted into eukaryotic expression vector pVAX1 to generate vaccines pVAX1-L1E6Mxx, E7Mxx. CHO cells were transiently transfected with the individual construct. Target protein expressions in the lysate of the transfected cells were measured by ELISA and immunocytochemistry. After BALB/c mice were vaccinated with various recombinant plasmids(pVAX1-L1-E6M3 or pVAX1-L1-E7M3) and immunie adjuvants (pLXHDmB7-2 or LTB) through different administration routes (intramuscular or intranasal) , the great cellular immune responses were produced as revealed by delayed-type hypersensitivity (DTH) and lymphocyte proliferation, and the expression of IL-4 and IFN- γ cells in CD4+ and CD8+subpopulations. Results The highly efficient expression of pVAX1-L1E6Mxx, E7Mxx vector in host eukaryotic cells were demonstrated both by ELISA and immunocytochemistry. The level of specific serum IgG against HPV in experiment groups mice was much higher than that of control group, and intranuscular immunization group had the highest antibody level. Intramuscular immunization groups were superior to intranasal immunization groups in DTH response, splenocyte proliferation and CD8+ IFN-γ + cells number, but CD4+ IL4+ cell number was higher in intranasal immunization groups. The immunization groups using pLXHDmB7-2 as adjuvant were superior to other groups in immunoresponse. Conclusion These DNA vaccines produce remarkable cellular and humoral immuneresponses in the mouse and may provide as prophylatic and therapeutic candidates for HPV induced cancer treatment.

  6. Hyaluronic Acid-Modified Cationic Lipid-PLGA Hybrid Nanoparticles as a Nanovaccine Induce Robust Humoral and Cellular Immune Responses.

    Science.gov (United States)

    Liu, Lanxia; Cao, Fengqiang; Liu, Xiaoxuan; Wang, Hai; Zhang, Chao; Sun, Hongfan; Wang, Chun; Leng, Xigang; Song, Cunxian; Kong, Deling; Ma, Guilei

    2016-05-18

    Here, we investigated the use of hyaluronic acid (HA)-decorated cationic lipid-poly(lactide-co-glycolide) acid (PLGA) hybrid nanoparticles (HA-DOTAP-PLGA NPs) as vaccine delivery vehicles, which were originally developed for the cytosolic delivery of genes. Our results demonstrated that after the NPs uptake by dendritic cells (DCs), some of the antigens that were encapsulated in HA-DOTAP-PLGA NPs escaped to the cytosolic compartment, and whereas some of the antigens remained in the endosomal/lysosomal compartment, where both MHC-I and MHC-II antigen presentation occurred. Moreover, HA-DOTAP-PLGA NPs led to the up-regulation of MHC, costimulatory molecules, and cytokines. In vivo experiments further revealed that more powerful immune responses were induced from mice immunized with HA-DOTAP-PLGA NPs when compared with cationic lipid-PLGA nanoparticles and free ovalbumin (OVA); the responses included antigen-specific CD4(+) and CD8(+) T-cell responses, the production of antigen-specific IgG antibodies and the generation of memory CD4(+) and CD8(+) T cells. Overall, these data demonstrate the high potential of HA-DOTAP-PLGA NPs for use as vaccine delivery vehicles to elevate cellular and humoral immune responses. PMID:27088457

  7. Cellular immune responses in patients with hepatitis B surface antigen seroclearance induced by antiviral therapy

    Directory of Open Access Journals (Sweden)

    Zhu Xiaolin

    2011-02-01

    Full Text Available Abstract Background The mechanisms by which chronic hepatitis B is completely resolved through antiviral therapy are unknown, and the contribution of acquired T cell immunity to hepatitis B surface antigen (HBsAg seroclearance has not been investigated. Therefore, we measured the T-cell responses to core and envelope antigens in patients with HBsAg seroclearance. Methods Fourteen subjects with HBsAg seroclearance following antiviral treatment for chronic hepatitis B, 7 HBeAg-positive immunotolerant HBV carriers and 9 HBeAg-negative inactive HBsAg carriers were recruited. HBV-specific T-cell responses to recombinant HBV core (rHBcAg and envelope (rHBsAg proteins and pools of core and envelope peptides were measured using an ELISPOT assay detecting interferon-gamma and intracellular cytokine staining (ICS assays detecting interferon-gamma or interleukin 2. Results Interferon-gamma ELISPOT assays showed a low frequency of weak responses to the rHBsAg and S peptide pool in the HBsAg seroclearance group, and the response frequency to the rHBcAg and the C peptide pool was higher than to the rHBsAg (P P = 0.001 respectively. A higher response frequency to C than S peptide pools was confirmed in the interferon-gamma ICS assays for both CD4+ (P = 0.033 and CD8+ (P = 0.040 T cells in the HBsAg seroclearance group. The responses to C and S antigens in the inactive carriers were similar. Conclusions There was a low frequency of CD4+ and CD8+ T cell immune responses to envelope antigens in Chinese subjects with HBsAg seroclearance following antiviral therapy. It is unlikely that these immune responses are responsible for HBsAg seroclearance in these subjects.

  8. 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

    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...

  9. Role of Humoral versus Cellular Responses Induced by a Protective Dengue Vaccine Candidate

    OpenAIRE

    Zellweger, Raphaël M.; Miller, Robyn; Eddy, William E.; White, Laura J.; Johnston, Robert E.; Shresta, Sujan

    2013-01-01

    Author Summary Dengue virus is an escalating public health threat for over 2.5 billion people worldwide. The disease caused by dengue virus ranges from mild (dengue fever) to lethal (dengue hemorrhagic fever, dengue shock syndrome). To date, there is no cure or vaccine for dengue. One of the challenges to developing a safe and efficient dengue vaccine is that antibodies, usually induced by vaccines to protect the host from re-infection, can increase the severity of dengue disease if they are ...

  10. Early Cellular Responses of Purine Nucleoside-mediated Protection of Hypoxia-induced Injuries of Neuronal PC12 Cells

    Directory of Open Access Journals (Sweden)

    Bettina Tomaselli

    2005-01-01

    Full Text Available Hypoxia in brain may lead to cell death by apoptosis and necrosis. In parallel adenosine, a powerful endogenous neuroprotectant is formed. We wanted to investigate the effect of adenosine and its purine nucleoside relatives, inosine and guanosine on early cellular responses to hypoxia. O2-sensitive neuronal PC12-cells were subjected to chemical hypoxia induced with rotenone, an inhibitor of mitochondrial complex I. Loss of viability after hypoxic insult was impressively rescued by adenosine, guanosine and inosine. PC12-cells mainly express the A2A adenosine receptor. Its inhibition with a specific antagonist (CSC induced cell death of PC12-cells, which could be salvaged by adenosine but not with guanosine or inosine. We have previously demonstrated the important role of mitogen activated protein kinases 1/2 (p42/44 MAPK in purine-mediated rescue. In this study we were interested in the involvement of protein kinases whose activities mediate these processes, including protein kinase A (PKA, phosphoinositide 3-kinase (PI3-K and protein kinase C-related kinases (PRK 1/2. Pharmacological inhibition of PKA and PI3-K increased hypoxia-induced toxicity and likewise also affected the rescue by purine nucleosides. Nerve growth factor (NGF and purine nucleosides induced an activation of PRK 1/2, which to our knowledge indicates for the first time that these kinases are potentially involved in purine nucleoside-mediated rescue of hypoxic neuronal cells. Results suggest that A2A receptor expressing cells are mainly dependent on the purine nucleoside adenosine for their rescue after hypoxic insult. In addition to PKA, PI3-K is an important effector molecule in A2A-mediated signaling and for the rescue of PC12-cells after hypoxic insult.

  11. 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.

  12. Trans-cellular introduction of HIV-1 protein Nef induces pathogenic response in Caenorhabditis elegans.

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    Aamir Nazir

    Full Text Available BACKGROUND: Caenorhabditis elegans has emerged as a very powerful model for studying the host pathogen interactions. Despite the absence of a naturally occurring viral infection for C. elegans, the model is now being exploited experimentally to study the basic aspects of virus-host interplay. The data generated from recent studies suggests that the virus that infects mammalian cells does infect, replicate and accumulate in C. elegans. METHODOLOGY/PRINCIPAL FINDINGS: We took advantage of the easy-to-achieve protein introduction in C. elegans and employing the methodology, we administered HIV-1 protein Nef into live worms. Nef is known to be an important protein for exacerbating HIV-1 pathogenesis in host by enhancing viral replication. The deletion of nef from the viral genome has been reported to inhibit its replication in the host, thereby leading to delayed pathogenesis. Our studies, employing Nef introduction into C. elegans, led to creation of an in-vivo model that allowed us to study, whether or not, the protein induces effect in the whole organism. We observed a marked lipodystrophy, effect on neuromuscular function, impaired fertility and reduced longevity in the worms exposed to Nef. The observed effects resemble to those observed in Nef transgenic mice and most interestingly the effects also relate to some of the pathogenic aspects exhibited by human AIDS patients. CONCLUSIONS/SIGNIFICANCE: Our studies underline the importance of this in vivo model for studying the interactions of Nef with host proteins, which could further be used for identifying possible inhibitors of such interactions.

  13. A mathematical model of radiation-induced responses in a cellular population including cell-to-cell communications

    International Nuclear Information System (INIS)

    Cell-to-cell communication is an important factor for understanding the mechanisms of radiation-induced responses such as bystander effects. In this study, a new mathematical model of intercellular signalling between individual cells in a cellular population is proposed. The authors considered two types of transmission of signals: via culture medium and via gap junction. They focus on the effects that radiation and intercellular signalling have on cell-cycle modification. The cell cycle is represented as a virtual clock that includes several checkpoint pathways within a cyclic process. They also develop a grid model and set up diffusion equations to model the propagation of signals to and from spatially located cells. The authors have also considered the role that DNA damage plays in the cycle of cells which can progress through the cell cycle or stop at the G1, S, G2 or M-phase checkpoints. Results of testing show that the proposed model can simulate intercellular signalling and cell-cycle progression in individual cells during and after irradiation. (authors)

  14. Pathogen-Mimicking Polymeric Nanoparticles based on Dopamine Polymerization as Vaccines Adjuvants Induce Robust Humoral and Cellular Immune Responses.

    Science.gov (United States)

    Liu, Qi; Jia, Jilei; Yang, Tingyuan; Fan, Qingze; Wang, Lianyan; Ma, Guanghui

    2016-04-01

    Aiming to enhance the immunogenicity of subunit vaccines, a novel antigen delivery and adjuvant system based on dopamine polymerization on the surface of poly(D,L-lactic-glycolic-acid) nanoparticles (NPs) with multiple mechanisms of immunity enhancement is developed. The mussel-inspired biomimetic polydopamine (pD) not only serves as a coating to NPs but also functionalizes NP surfaces. The method is facile and mild including simple incubation of the preformed NPs in the weak alkaline dopamine solution, and incorporation of hepatitis B surface antigen and TLR9 agonist unmethylated cytosine-guanine (CpG) motif with the pD surface. The as-constructed NPs possess pathogen-mimicking manners owing to their size, shape, and surface molecular immune-activating properties given by CpG. The biocompatibility and biosafety of these pathogen-mimicking NPs are confirmed using bone marrow-derived dendritic cells. Pathogen-mimicking NPs hold great potential as vaccine delivery and adjuvant system due to their ability to: 1) enhance cytokine secretion and immune cell recruitment at the injection site; 2) significantly activate and maturate dendritic cells; 3) induce stronger humoral and cellular immune responses in vivo. Furthermore, this simple and versatile dopamine polymerization method can be applicable to endow NPs with characteristics to mimic pathogen structure and function, and manipulate NPs for the generation of efficacious vaccine adjuvants. PMID:26849717

  15. Near-infrared dye loaded polymeric nanoparticles for cancer imaging and therapy and cellular response after laser-induced heating

    Directory of Open Access Journals (Sweden)

    Tingjun Lei

    2014-03-01

    Full Text Available Background: In the past decade, researchers have focused on developing new biomaterials for cancer therapy that combine imaging and therapeutic agents. In our study, we use a new biocompatible and biodegradable polymer, termed poly(glycerol malate co-dodecanedioate (PGMD, for the synthesis of nanoparticles (NPs and loading of near-infrared (NIR dyes. IR820 was chosen for the purpose of imaging and hyperthermia (HT. HT is currently used in clinical trials for cancer therapy in combination with radiotherapy and chemotherapy. One of the potential problems of HT is that it can up-regulate hypoxia-inducible factor-1 (HIF-1 expression and enhance vascular endothelial growth factor (VEGF secretion.Results: We explored cellular response after rapid, short-term and low thermal dose laser-IR820-PGMD NPs (laser/NPs induced-heating, and compared it to slow, long-term and high thermal dose heating by a cell incubator. The expression levels of the reactive oxygen species (ROS, HIF-1 and VEGF following the two different modes of heating. The cytotoxicity of NPs after laser/NP HT resulted in higher cell killing compared to incubator HT. The ROS level was highly elevated under incubator HT, but remained at the baseline level under the laser/NP HT. Our results show that elevated ROS expression inside the cells could result in the promotion of HIF-1 expression after incubator induced-HT. The VEGF secretion was also significantly enhanced compared to laser/NP HT, possibly due to the promotion of HIF-1. In vitro cell imaging and in vivo healthy mice imaging showed that IR820-PGMD NPs can be used for optical imaging.Conclusion: IR820-PGMD NPs were developed and used for both imaging and therapy purposes. Rapid and short-term laser/NP HT, with a low thermal dose, does not up-regulate HIF-1 and VEGF expression, whereas slow and long term incubator HT, with a high thermal dose, enhances the expression of both transcription factors.

  16. Quillaja brasiliensis saponins induce robust humoral and cellular responses in a bovine viral diarrhea virus vaccine in mice.

    Science.gov (United States)

    Cibulski, Samuel Paulo; Silveira, Fernando; Mourglia-Ettlin, Gustavo; Teixeira, Thais Fumaco; dos Santos, Helton Fernandes; Yendo, Anna Carolina; de Costa, Fernanda; Fett-Neto, Arthur Germano; Gosmann, Grace; Roehe, Paulo Michel

    2016-04-01

    A saponin fraction extracted from Quillaja brasiliensis leaves (QB-90) and a semi-purified aqueous extract (AE) were evaluated as adjuvants in a bovine viral diarrhea virus (BVDV) vaccine in mice. Animals were immunized on days 0 and 14 with antigen plus either QB-90 or AE or an oil-adjuvanted vaccine. Two-weeks after boosting, antibodies were measured by ELISA; cellular immunity was evaluated by DTH, lymphoproliferation, cytokine release and single cell IFN-γ production. Serum anti-BVDV IgG, IgG1 and IgG2b were significantly increased in QB-90- and AE-adjuvanted vaccines. A robust DTH response, increased splenocyte proliferation, Th1-type cytokines and enhanced production of IFN-γ by CD4(+) and CD8(+) T lymphocytes were detected in mice that received QB-90-adjuvanted vaccine. The AE-adjuvanted preparation stimulated humoral responses but not cellular immune responses. These findings reveal that QB-90 is capable of stimulating both cellular and humoral immune responses when used as adjuvant. PMID:27012913

  17. A single dose of inactivated hepatitis A vaccine promotes HAV-specific memory cellular response similar to that induced by a natural infection.

    Science.gov (United States)

    Melgaço, Juliana Gil; Morgado, Lucas Nóbrega; Santiago, Marta Almeida; Oliveira, Jaqueline Mendes de; Lewis-Ximenez, Lia Laura; Hasselmann, Bárbara; Cruz, Oswaldo Gonçalves; Pinto, Marcelo Alves; Vitral, Claudia Lamarca

    2015-07-31

    Based on current studies on the effects of single dose vaccines on antibody production, Latin American countries have adopted a single dose vaccine program. However, no data are available on the activation of cellular response to a single dose of hepatitis A. Our study investigated the functional reactivity of the memory cell phenotype after hepatitis A virus (HAV) stimulation through administration of the first or second dose of HAV vaccine and compared the response to that of a baseline group to an initial natural infection. Proliferation assays showed that the first vaccine dose induced HAV-specific cellular response; this response was similar to that induced by a second dose or an initial natural infection. Thus, from the first dose to the second dose, increase in the frequencies of classical memory B cells, TCD8 cells, and central memory TCD4 and TCD8 cells were observed. Regarding cytokine production, increased IL-6, IL-10, TNF, and IFNγ levels were observed after vaccination. Our findings suggest that a single dose of HAV vaccine promotes HAV-specific memory cell response similar to that induced by a natural infection. The HAV-specific T cell immunity induced by primary vaccination persisted independently of the protective plasma antibody level. In addition, our results suggest that a single dose immunization system could serve as an alternative strategy for the prevention of hepatitis A in developing countries. PMID:26144899

  18. Intradermal DNA Electroporation Induces Cellular and Humoral Immune Response and Confers Protection against HER2/neu Tumor

    Directory of Open Access Journals (Sweden)

    Alessia Lamolinara

    2015-01-01

    Full Text Available Skin represents an attractive target for DNA vaccine delivery because of its natural richness in APCs, whose targeting may potentiate the effect of vaccination. Nevertheless, intramuscular electroporation is the most common delivery method for ECTM vaccination. In this study we assessed whether intradermal administration could deliver the vaccine into different cell types and we analyzed the evolution of tissue infiltrate elicited by the vaccination protocol. Intradermal electroporation (EP vaccination resulted in transfection of different skin layers, as well as mononuclear cells. Additionally, we observed a marked recruitment of reactive infiltrates mainly 6–24 hours after treatment and inflammatory cells included CD11c+. Moreover, we tested the efficacy of intradermal vaccination against Her2/neu antigen in cellular and humoral response induction and consequent protection from a Her2/neu tumor challenge in Her2/neu nontolerant and tolerant mice. A significant delay in transplantable tumor onset was observed in both BALB/c (p≤0,0003 and BALB-neuT mice (p=0,003. Moreover, BALB-neuT mice displayed slow tumor growth as compared to control group (p<0,0016. In addition, while in vivo cytotoxic response was observed only in BALB/c mice, a significant antibody response was achieved in both mouse models. Our results identify intradermal EP vaccination as a promising method for delivering Her2/neu DNA vaccine.

  19. Epithelial Adhesion Mediated by Pilin SpaC Is Required for Lactobacillus rhamnosus GG-Induced Cellular Responses

    OpenAIRE

    Ardita, Courtney S.; Mercante, Jeffrey W; Kwon, Young Man; Luo, Liping; Crawford, Madelyn E.; Powell, Domonica N.; Jones, Rheinallt M.; Neish, Andrew S.

    2014-01-01

    Lactobacillus rhamnosus GG is a widely used probiotic, and the strain's salutary effects on the intestine have been extensively documented. We previously reported that strain GG can modulate inflammatory signaling, as well as epithelial migration and proliferation, by activating NADPH oxidase 1-catalyzed generation of reactive oxygen species (ROS). However, how strain GG induces these responses is unknown. Here, we report that strain GG's probiotic benefits are dependent on the bacterial-epit...

  20. Immunopotentiation of Different Adjuvants on Humoral and Cellular Immune Responses Induced by HA1-2 Subunit Vaccines of H7N9 Influenza in Mice.

    Directory of Open Access Journals (Sweden)

    Li Song

    Full Text Available In spring 2013, human infections with a novel avian influenza A (H7N9 virus were reported in China. The number of cases has increased with over 200 mortalities reported to date. However, there is currently no vaccine available for the H7 subtype of influenza A virus. Virus-specific cellular immune responses play a critical role in virus clearance during influenza infection. In this study, we undertook a side-by-side evaluation of two different adjuvants, Salmonella typhimurium flagellin (fliC and polyethyleneimine (PEI, through intraperitoneal administration to assess their effects on the immunogenicity of the recombinant HA1-2 subunit vaccine of H7N9 influenza. The fusion protein HA1-2-fliC and HA1-2 combined with PEI could induce significantly higher HA1-2-specific IgG and hemagglutination inhibition titers than HA1-2 alone at 12 days post-boost, with superior HA1-2 specific IgG titers in the HA1-2-fliC group compared with the PEI adjuvanted group. The PEI adjuvanted vaccine induced higher IgG1/IgG2a ratio and significantly increased numbers of IFN-γ- and IL-4-producing cells than HA1-2 alone, suggesting a mixed Th1/Th2-type cellular immune response with a Th2 bias. Meanwhile, the HA1-2-fliC induced higher IgG2a and IgG1 levels, which is indicative of a mixed Th1/Th2-type profile. Consistent with this, significant levels, and equal numbers, of IFN-γ- and IL-4-producing cells were detected after HA1-2-fliC vaccination. Moreover, the marked increase in CD69 expression and the proliferative index with the HA1-2-fliC and PEI adjuvanted vaccines indicated that both adjuvanted vaccine candidates effectively induced antigen-specific cellular immune responses. Taken together, our findings indicate that the two adjuvanted vaccine candidates elicit effective and HA1-2-specific humoral and cellular immune responses, offering significant promise for the development of a successful recombinant HA1-2 subunit vaccine for H7N9 influenza.

  1. Immune cellular response to HPV: current concepts

    Directory of Open Access Journals (Sweden)

    Maria Alice Guimarães Gonçalves

    2004-02-01

    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.

  2. Barrier protective effects of withaferin A in HMGB1-induced inflammatory responses in both cellular and animal models

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Wonhwa [College of Pharmacy, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University (Korea, Republic of); Kim, Tae Hoon [Department of Herbal Medicinal Pharmacology, Daegu Haany University (Korea, Republic of); Ku, Sae-Kwang [Department of Anatomy and Histology, College of Oriental Medicine, Daegu Haany University, Gyeongsan 712-715 (Korea, Republic of); Min, Kyoung-jin [Department of Immunology, School of Medicine, Keimyung University, Daegu 704-701 (Korea, Republic of); Lee, Hyun-Shik [School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kwon, Taeg Kyu [Department of Immunology, School of Medicine, Keimyung University, Daegu 704-701 (Korea, Republic of); Bae, Jong-Sup, E-mail: baejs@knu.ac.kr [College of Pharmacy, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of)

    2012-07-01

    Withaferin A (WFA), an active compound from Withania somnifera, is widely researched for its anti-inflammatory, cardioactive and central nervous system effects. In this study, we first investigated the possible barrier protective effects of WFA against pro-inflammatory responses in human umbilical vein endothelial cells (HUVECs) and in mice induced by high mobility group box 1 protein (HMGB1) and the associated signaling pathways. The barrier protective activities of WFA were determined by measuring permeability, leukocytes adhesion and migration, and activation of pro-inflammatory proteins in HMGB1-activated HUVECs. We found that WFA inhibited lipopolysaccharide (LPS)-induced HMGB1 release and HMGB1-mediated barrier disruption, expression of cell adhesion molecules (CAMs) and adhesion/transendothelial migration of leukocytes to human endothelial cells. WFA also suppressed acetic acid-induced hyperpermeability and carboxymethylcellulose-induced leukocytes migration in vivo. Further studies revealed that WFA suppressed the production of interleukin 6, tumor necrosis factor-α (TNF-α) and activation of nuclear factor-κB (NF-κB) by HMGB1. Collectively, these results suggest that WFA protects vascular barrier integrity by inhibiting hyperpermeability, expression of CAMs, adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapy for vascular inflammatory diseases. -- Highlights: ► Withaferin A inhibited LPS induced HMGB1 release. ► Withaferin A reduced HMGB1-mediated hyperpermeability. ► Withaferin A inhibited HMGB1-mediated adhesion and migration of leukocytes. ► Withaferin A inhibited HMGB1-mediated activation of NF-κB, IL-6 and TNF-α.

  3. Hypoxia-inducible factors in T lymphocyte differentiation and function. A Review in the Theme: Cellular Responses to Hypoxia.

    Science.gov (United States)

    Tao, Jin-Hui; Barbi, Joseph; Pan, Fan

    2015-11-01

    Low oxygen concentrations or hypoxia is a trait common to inflamed tissues. Therefore it is not surprising that pathways of hypoxic stress response, largely governed by hypoxia-inducible factors (HIF), are highly relevant to the proper function of immune cells. HIF expression and stabilization in immune cells can be triggered not only by hypoxia, but also by a variety of stimuli and pathological stresses associated with leukocyte activation and inflammation. In addition to its role as a sensor of oxygen scarcity, HIF is also a major regulator of immune cell metabolic function. Rapid progress is being made in elucidating the roles played by HIF in diverse aspects of both innate and adaptive immunity. Here we discuss a number of breakthroughs that have shed light on how HIF expression and activity impact the differentiation and function of diverse T cell populations. The insights gained from these findings may serve as the foundation for future therapies aimed at fine-tuning the immune response. PMID:26354751

  4. Cellular immune responses of BALB/c mice induced by intramuscular injection of PRRSV-ORF5 DNA vaccine with different doses

    Institute of Scientific and Technical Information of China (English)

    CHENG Anchun; WANG Mingshu; CHEN Xiwen; XINI Nigen; DOU Wenbo; LI Xuemei; LIU Wumei; WANG Gang; ZHANG Pingying

    2007-01-01

    BALB/c mice were immunized with 50 μg,100 μg,200 μg of pcDNA-PRRSV-ORF5 DNA vaccine respectively by intramuscular injection,with PBS and pcDNA3.1(+)as controls.Fluorescence activated cell Sorter (FACS)was used to detect the number of CD4+ and CD8+T-lymphocytes.T-lymphocyte proliferation test was used to detect proliferation of the T-lymphocyte cells in peripheral blood lymphocytes of mice vaccinated with pcDNA-PRRSV-ORF5 DNA vaccine.The results showed that the difference in ConA response to T-lymphocytes in blood was highly significant between all experimental groups and the control group(P<0.01).The number of CD4+T-lymphocytes in experimental groups was significantly higher than that of the control group 7d after vaccination.The number of CD8+ T-lymphocytes in the experimental groups was higher than that of the control group 28 d after vaccination.Mice immunized with a higher dose(200 μg)of DNA vaccine demonstrated higher cellular immune response than those immunized with a lower dose(100 μg,50 μg)of DNA vaccine.The results demonstrated that pcDNA-PRRSV-ORF5 DNA vaccine could induce a good cellular immune response which may be dose-dependent.

  5. Regulation of N-methyl-D-aspartate receptor expression and N-methyl-D-aspartate-induced cellular response during chronic hypoxia in differentiated rat PC12 cells.

    Science.gov (United States)

    Kobayashi, S; Millhorn, D E

    2000-01-01

    The purpose of the present study was to examine the effect of chronic hypoxia on N-methyl-D-aspartate-mediated cellular responses in differentiated PC12 cells. PC12 cells were differentiated by treatment with nerve growth factor. Patch-clamp analysis in differentiated PC12 cells showed that extracellularly applied N-methyl-D-aspartate induced an inward current that was abolished by the presence of the N-methyl-D-aspartate receptor antagonist MK-801. Results from Ca(2+) imaging experiments showed that N-methyl-D-aspartate induced an elevation in intracellular free Ca(2+) which was also abolished by MK-801. We also examined the effect of hypoxia on the N-methyl-D-aspartate-induced current in nerve growth factor-treated cells. We found that the N-methyl-D-aspartate-induced inward current and the N-methyl-D-aspartate-induced elevation in intracellular free Ca(2+) were markedly attenuated by chronic hypoxia. We next examined the possibility that the reduced N-methyl-D-aspartate responsiveness was due to down-regulation of N-methyl-D-aspartate receptor levels. Northern blot and immunoblot analyses showed that both messenger RNA and protein levels for N-methyl-D-aspartate receptor subunit 1 were markedly decreased during hypoxia. However, the messenger RNA for N-methyl-D-aspartate receptor subunit 2C was increased, whereas the protein level for subunit 2C did not change. Our results indicate that differentiated PC12 cells express functional N-methyl-D-aspartate receptors and that chronic exposure to hypoxia attenuates the N-methyl-D-aspartate-induced Ca(2+) accumulation in these cells via down-regulation of N-methyl-D-aspartate receptor subunit 1. This mechanism may play an important role in protecting PC12 cells against hypoxic stress. PMID:11113364

  6. DNA-based vaccination induces humoral and cellular immune responses against hepatitis B virus surface antigen in mice without activation of Cmyc

    Institute of Scientific and Technical Information of China (English)

    Lian San Zhao; Shan Qin; Tao You Zhou; Hong Tang; Li Liu; Bing Jun Lei

    2000-01-01

    AIM To develop a safe and effective DNA vaccine for inducing humoral and cellular immunological responses against hepatitis B virus surface antigen (HBsAg). METHODS BALB/c mice were inoculated with NV-HB/s, a recombinant plasmid that had been inserted S gene of hepatitis B virus genome and could express HBsAg in eukaryotes. HBsAg expression was measured by ABC immunohistochemical assay, generation of anti-HBs by ELISA and cytotoxic T lymphocyte (CTL), by MTT method, existence of vaccine DNA by Southern blot hybridization and activation of oncogene C-myc by in situ hybridization.RESULTS With NV-HB/s vaccination by intramuscular injection, anti-HBs was initially positive 2 weeks after inoculation while all mice tested were HBsAg positive in the muscles. The titers and seroconversion rate of anti-HBs were steadily increasing as time went on and were dose-dependent. All the mice inoculated with 100 μg NV-HB/ s were anti-HBs positive one month after inoculation, the titer was 1:1024 or more. The humoral immune response was similar induced by either intramuscular or intradermal injection. CTL activities were much stronger (45.26%) in NV-HB/s DNA immunized mice as compared with those (only 6%) in plasmaderived HBsAg vaccine immunized mice. Two months after inoculation, all muscle samples were positive by Southern-blot hybridization for NV-HB/s DNA detection, but decreased to 25%and all were undetectable by in situ hybridization after 6 months. No oncogene Cmyc activation was found in the muscle of inoculation site. CONCLUSION NV-HB/s could generate humoral and cellular immunological responses against HBsAg that had been safely expressed in situ by NV-HB/s vaccination.

  7. Studies of cell-surface glorin receptors, glorin degradation, and glorin-induced cellular responses during development of Polysphondylium violaceum.

    Science.gov (United States)

    De Wit, R J; van Bemmelen, M X; Penning, L C; Pinas, J E; Calandra, T D; Bonner, J T

    1988-12-01

    The chemoattractant mediating cell aggregation in the slime mold Polysphondylium violaceum is N-propionyl-gamma-L-glutamyl-L-ornithine-delta-lactam ethylester (glorin). Here we examine the binding properties of tritiated glorin to intact P. violaceum cells. Scatchard analysis of binding data yielded slightly curvilinear plots with Kd values in the range of 20 and 100 nM. The number of glorin receptors increased from 35,000 in the vegetative stage to 45,000 per cell during aggregation. Later, during culmination receptor numbers decreased to undetectable levels (less than 1000). The receptor binding kinetics show binding equilibrium within 30 s at 0 degrees C, and ligand dissociation occurs from two kinetically distinct receptors whose half-times were 2 s for 72% of the bound glorin and 28 s for the remainder. The enzymatic degradation of glorin did not affect binding data during incubations of up to 1 min at 0 degrees C. Two glorinase activities were observed. An ornithine delta-lactam cleaving activity with a Km of ca. 10(-4) M and a propionic acid removing activity (Km 10(-5) M), both of which were detected mainly on the cell surface. Cleavage of the lactam occurred at a higher rate than removal of propionic acid. Lactam-cleaved glorin showed no chemotactic activity nor did it bind to cell-surface glorin receptors. Cell-surface-bound glorinase activity and glorin-induced cGMP synthesis were developmentally regulated, peaking at aggregation. In the most sensitive stage half-maximal responses (cGMP synthesis, chemotaxis, light-scattering) were elicited in the 10-100 nM range. Neither cAMP synthesis nor glorin-induced glorin synthesis was observed. Guanine nucleotides specifically modulated glorin receptor binding on isolated membranes, and, conversely, glorin modulated GTP gamma S binding to membrane preparations. Our results support the notion that glorin mediates chemotactic cell aggregation in P. violaceum acting via cell-surface receptors, G-proteins, and c

  8. Sulfur and nitrogen mustards induce characteristic poly(ADP-ribosyl)ation responses in HaCaT keratinocytes with distinctive cellular consequences.

    Science.gov (United States)

    Mangerich, Aswin; Debiak, Malgorzata; Birtel, Matthias; Ponath, Viviane; Balszuweit, Frank; Lex, Kirsten; Martello, Rita; Burckhardt-Boer, Waltraud; Strobelt, Romano; Siegert, Markus; Thiermann, Horst; Steinritz, Dirk; Schmidt, Annette; Bürkle, Alexander

    2016-02-26

    Mustard agents are potent DNA alkylating agents with mutagenic, cytotoxic and vesicant properties. They include bi-functional agents, such as sulfur mustard (SM) or nitrogen mustard (mustine, HN2), as well as mono-functional agents, such as "half mustard" (CEES). Whereas SM has been used as a chemical warfare agent, several nitrogen mustard derivatives, such as chlorambucil and cyclophosphamide, are being used as established chemotherapeutics. Upon induction of specific forms of genotoxic stimuli, several poly(ADP-ribose) polymerases (PARPs) synthesize the nucleic acid-like biopolymer poly(ADP-ribose) (PAR) by using NAD(+) as a substrate. Previously, it was shown that SM triggers cellular poly(ADP-ribosyl) ation (PARylation), but so far this phenomenon is poorly characterized. In view of the protective effects of PARP inhibitors, the latter have been proposed as a treatment option of SM-exposed victims. In an accompanying article (Debiak et al., 2016), we have provided an optimized protocol for the analysis of the CEES-induced PARylation response in HaCaT keratinocytes, which forms an experimental basis to further analyze mustard-induced PARylation and its functional consequences, in general. Thus, in the present study, we performed a comprehensive characterization of the PARylation response in HaCaT cells after treatment with four different mustard agents, i.e., SM, CEES, HN2, and chlorambucil, on a qualitative, quantitative and functional level. In particular, we recorded substance-specific as well as dose- and time-dependent PARylation responses using independent bioanalytical methods based on single-cell immuno-fluorescence microscopy and quantitative isotope dilution mass spectrometry. Furthermore, we analyzed if and how PARylation contributes to mustard-induced toxicity by treating HaCaT cells with CEES, SM, and HN2 in combination with the clinically relevant PARP inhibitor ABT888. As evaluated by a novel immunofluorescence-based protocol for the detection of

  9. Cellular host responses to gliomas.

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    Joseph Najbauer

    Full Text Available BACKGROUND: Glioblastoma multiforme (GBM is the most aggressive type of malignant primary brain tumors in adults. Molecular and genetic analysis has advanced our understanding of glioma biology, however mapping the cellular composition of the tumor microenvironment is crucial for understanding the pathology of this dreaded brain cancer. In this study we identified major cell populations attracted by glioma using orthotopic rodent models of human glioma xenografts. Marker-specific, anatomical and morphological analyses revealed a robust influx of host cells into the main tumor bed and tumor satellites. METHODOLOGY/PRINCIPAL FINDINGS: Human glioma cell lines and glioma spheroid orthotopic implants were used in rodents. In both models, the xenografts recruited large numbers of host nestin-expressing cells, which formed a 'network' with glioma. The host nestin-expressing cells appeared to originate in the subventricular zone ipsilateral to the tumor, and were clearly distinguishable from pericytes that expressed smooth muscle actin. These distinct cell populations established close physical contact in a 'pair-wise' manner and migrated together to the deeper layers of tumor satellites and gave rise to tumor vasculature. The GBM biopsy xenografts displayed two different phenotypes: (a low-generation tumors (first in vivo passage in rats were highly invasive and non-angiogenic, and host nestin-positive cells that infiltrated into these tumors displayed astrocytic or elongated bipolar morphology; (b high-generation xenografts (fifth passage had pronounced cellularity, were angiogenic with 'glomerulus-like' microvascular proliferations that contained host nestin-positive cells. Stromal cell-derived factor-1 and its receptor CXCR4 were highly expressed in and around glioma xenografts, suggesting their role in glioma progression and invasion. CONCLUSIONS/SIGNIFICANCE: Our data demonstrate a robust migration of nestin-expressing host cells to glioma, which

  10. Nine μg intradermal influenza vaccine and 15 μg intramuscular influenza vaccine induce similar cellular and humoral immune responses in adults

    Science.gov (United States)

    Nougarede, Nolwenn; Bisceglia, Hélène; Rozières, Aurore; Goujon, Catherine; Boudet, Florence; Laurent, Philippe; Vanbervliet, Beatrice; Rodet, Karen; Hennino, Ana; Nicolas, Jean-François

    2014-01-01

    Intanza® 9 μg (Sanofi Pasteur), a trivalent split-virion vaccine administered by intradermal (ID) injection, was approved in Europe in 2009 for the prevention of seasonal influenza in adults 18 to 59 years. Here, we examined the immune responses induced in adults by the ID 9 μg vaccine and the standard trivalent intramuscular (IM) vaccine (Vaxigrip® 15 μg, Sanofi Pasteur). This trial was a randomized, controlled, single-center, open-label study in healthy adults 18 to 40 years of age during the 2007/8 influenza season. Subjects received a single vaccination with the ID 9 μg (n = 38) or IM 15 μg (n = 42) vaccine. Serum, saliva, and peripheral blood mononuclear cells were collected up to 180 days post-vaccination. Geometric mean hemagglutination inhibition titers, seroprotection rates, seroconversion rates, and pre-vaccination-to-post-vaccination ratios of geometric mean hemagglutination inhibition titers did not differ between the two vaccines. Compared with pre-vaccination, the vaccines induced similar increases in vaccine-specific circulating B cells at day 7 but did not induce significant increases in vaccine-specific memory B cells at day 180. Cell-mediated immunity to all three vaccine strains, measured in peripheral blood mononuclear cells, was high at baseline and not increased by either vaccine. Neither vaccine induced a mucosal immune response. These results show that the humoral and cellular immune responses to the ID 9 μg vaccine are similar to those to the standard IM 15 μg vaccine. PMID:25483667

  11. Dietary turmeric modulates DMBA-induced p21ras, MAP kinases and AP-1/NF-κB pathway to alter cellular responses during hamster buccal pouch carcinogenesis

    International Nuclear Information System (INIS)

    The chemopreventive efficacy of turmeric has been established in experimental systems. However, its mechanism(s) of action are not fully elucidated in vivo. The present study investigates the mechanism of turmeric-mediated chemoprevention in 7,12-dimethylbenz(a)anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis at 2, 4, 6, 10 and 12 weeks. Dietary turmeric (1%) led to decrease in DMBA-induced tumor burden and multiplicity, and enhanced the latency period in parallel, to its modulatory effects on oncogene products and various cellular responses during HBP tumorigenesis. DMBA-induced expression of ras oncogene product, p21 and downstream target, the mitogen-activated protein kinases were significantly decreased by turmeric during HBP carcinogenesis. Turmeric also diminished the DMBA-induced mRNA expression of proto-oncogenes (c-jun, c-fos) and NF-κB, leading to decreased protein levels and in further attenuation of DMBA-induced AP-1/NF-κB DNA-binding in the buccal pouch nuclear extracts. Besides, buccal pouch of hamsters receiving turmeric diet showed significant alterations in DMBA-induced effects: (a) decrease in cell proliferation (diminished PCNA and Bcl2 expression), (b) enhanced apoptosis (increased expression of Bax, caspase-3 and apoptotic index), (c) decrease in inflammation (levels of Cox-2, the downstream target of AP-1/NF-κB, and PGE2) and (d) aberrant expression of differentiation markers, the cytokeratins (1, 5, 8, and 18). Together, the protective effects of dietary turmeric converge on augmenting apoptosis of the initiated cells and decreasing cell proliferation in DMBA-treated animals, which in turn, is reflected in decreased tumor burden, multiplicity and enhanced latency period. Some of these biomarkers are likely to be helpful in monitoring clinical trials and evaluating drug effect measurements

  12. Cellular basis of radiation-induced fibrosis

    International Nuclear Information System (INIS)

    Fibrosis is a common sequela of both cancer treatment by radiotherapy and accidental irradiation and has been described in many tissues including skin, lung, heart and liver. The underlying mechanisms of the radiation-induced fibrosis still remain to be resolved. In the present review we tried to illustrate the basic cellular mechanisms of radiation-induced fibrosis based on the newest findings arising from molecular radiobiology and cell biology. Based on these findings the cellular mechanism of radiation-induced fibrosis can be seen as a multicellular process involving various interacting cell systems in the target organ resulting in the fibrotic phenotype of the fibroblast/fibrocyte cell system

  13. Paraquat induces epithelial-mesenchymal transition-like cellular response resulting in fibrogenesis and the prevention of apoptosis in human pulmonary epithelial cells.

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    Atsushi Yamada

    Full Text Available The aim of this study is to investigate the molecular mechanisms underlying delayed progressive pulmonary fibrosis, a characteristic of subacute paraquat (PQ poisoning. Epithelial-mesenchymal transition (EMT has been proposed as a cause of organ fibrosis, and transforming growth factor-β (TGF-β is suggested to be a powerful mediator of EMT. We thus examined the possibility that EMT is involved in pulmonary fibrosis during PQ poisoning using A549 human alveolar epithelial cells in vitro. The cells were treated with various concentrations of PQ (0-500 μM for 2-12 days. Short-term (2 days high-dose (>100 μM treatments with PQ induced cell death accompanied by the activation of caspase9 as well as a decrease in E-cadherin (an epithelial cell marker, suggesting apoptotic cell death with the features of anoikis (cell death due to the loss of cell-cell adhesion. In contrast, long-term (6-12 days low-dose (30 μM treatments with PQ resulted in a transformation into spindle-shaped mesenchymal-like cells with a decrease of E-cadherin as well as an increase of α-smooth muscle actin (α-SMA. The mesenchymal-like cells also secreted the extracellular matrix (ECM protein fibronectin into the culture medium. The administration of a TGF-β1 receptor antagonist, SB431542, almost completely attenuated the mesenchymal transformation as well as fibronectin secretion, suggesting a crucial role of TGF-β1 in EMT-like cellular response and subsequent fibrogenesis. It is noteworthy that despite the suppression of EMT-fibrogenesis, apoptotic death was observed in cells treated with PQ+SB431542. EMT-like cellular response and subsequent fibrogenesis were also observed in normal human bronchial epithelial (NHBE cells exposed to PQ in a TGF-β1-dependent manner. Taken together, our experimental model reflects well the etiology of PQ poisoning in human and shows the involvement of EMT-like cellular response in both fibrogenesis and resistance to cell death during

  14. Phagocytosis, a cellular immune response in insects

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    C Rosales

    2011-06-01

    Full Text Available Insects like many other organisms are exposed to a wide range of infectious agents. Defense against these agents is provided by innate immune systems, which include physical barriers, humoral responses, and cellular responses. The humoral responses are characterized by the production of antimicrobial peptides, while the cellular defense responses include nodulation, encapsulation, melanization and phagocytosis. The phagocytic process, whereby cells ingest large particles, is of fundamental importance for insects’ development and survival. Phagocytic cells recognize foreign particles through a series of receptors on their cell membrane for pathogen-associated molecules. These receptors in turn initiate a series of signaling pathways that instruct the cell to ingest and eventually destroy the foreign particle. This review describes insect innate humoral and cellular immune functions with emphasis on phagocytosis. Recent advances in our understanding of the phagocytic cell types in various insect species; the receptors involved and the signaling pathways activated during phagocytosis are discussed.

  15. Cellular responses induced in vitro by pestheic acid, a fungal metabolite, in a gastric adenocarcinoma cell line (PG100).

    Science.gov (United States)

    Sousa, J M C; Matos, L A; Alcântara, D F A; Ribeiro, H F; Santos, L S; Oliveira, M N; Brito-Junior, L C; Khayat, A S; Guimarães, A C; Cunha, L A; Burbano, R R; Bahia, M O

    2013-01-01

    There is a constant search for new cancer treatments that are less aggressive and economically affordable. In this context, natural products extracted from plants, fungi, and microorganisms are of great interest. Pestheic acid, or dihidromaldoxin, is a chlorinated diphenylic ether extracted from the phytopathogenic fungus Pestalotiopsis guepinii (Amphisphaeriaceae). We assessed the cytotoxic, cytostatic, and genotoxic effects of pestheic acid in a gastric adenocarcinoma cell line (PG100). A decrease in clonogenic survival was observed. Pestheic acid also induced significant increases in both micronucleus and nucleoplasmic bridge frequency. However, we did not observe changes in cell cycle kinetics or apoptosis induction. Reactive oxygen species induced by diphenylic ethers may explain the genotoxicity and mutagenicity of pestheic acid. The absence of repair checkpoints that we observed is probably due to the fact that the PG100 cell line lacks the TP53 gene, which is common in gastric cancers. Even though pestheic acid has had a clear cytotoxic effect, the minimal inhibitory concentration was high, which shows that pestheic acid is not an active anticancer compound under these conditions. PMID:24114206

  16. The bradykinin B2 receptor induces multiple cellular responses leading to the proliferation of human renal carcinoma cell lines

    International Nuclear Information System (INIS)

    The vasoactive peptide bradykinin (BK) acts as a potent growth factor for normal kidney cells, but there have been few studies on the role of BK in renal cell carcinomas. In this study, we tested the hypothesis that BK also acts as a mitogen in kidney carcinomas, and explored the effects of BK in human renal carcinoma A498 cells. The presence of mRNAs for BK B1 and BK B2 receptors in A498 cells was demonstrated by reverse transcription–polymerase chain reaction. To study BK signaling pathways, we employed fluorescent measurements of intracellular Ca2+, measured changes in extracellular pH as a reflection of Na+/H+ exchange (NHE) with a Cytosensor microphysiometer, and assessed extracellular signal-regulated kinase (ERK) activation by Western blotting. Exposure to 100 nM of BK resulted in the rapid elevation of intracellular Ca2+, caused a ≥30% increase in NHE activity, and a ≥300% increase in ERK phosphorylation. All BK signals were blocked by HOE140, a BK B2 receptor antagonist, but not by a B1 receptor antagonist. Inhibitor studies suggest that BK-induced ERK activation requires phospholipase C and protein kinase C activities, and is Ca2+/calmodulin-dependent. The amiloride analog 5-(N-methyl-N-isobutyl)-amiloride (MIA) blocked short-term NHE activation and inhibited ERK phosphorylation, suggesting that NHE is critical for ERK activation by BK. BK induced an approximately 40% increase in the proliferation of A498 cells as assessed by bromodeoxyuridine uptake. This effect was blocked by the ERK inhibitor PD98059, and was dependent on NHE activity. We conclude that BK exerts mitogenic effects in A498 cells via the BK B2 receptor activation of growth-associated NHE and ERK

  17. The bradykinin B2 receptor induces multiple cellular responses leading to the proliferation of human renal carcinoma cell lines

    Directory of Open Access Journals (Sweden)

    Kramarenko II

    2012-07-01

    Full Text Available Inga I Kramarenko1, Thomas A Morinelli1,2, Marlene A Bunni1,2, John R Raymond Sr3, Maria N Garnovskaya11Department of Medicine (Nephrology Division, Medical University of South Carolina, Charleston, SC, USA; 2Medical and Research Services of the Ralph H Johnson Veterans Affairs Medical Center, Charleston, SC, USA; 3Medical College of Wisconsin, Milwaukee, WI, USABackground: The vasoactive peptide bradykinin (BK acts as a potent growth factor for normal kidney cells, but there have been few studies on the role of BK in renal cell carcinomas.Purpose: In this study, we tested the hypothesis that BK also acts as a mitogen in kidney carcinomas, and explored the effects of BK in human renal carcinoma A498 cells.Methods: The presence of mRNAs for BK B1 and BK B2 receptors in A498 cells was demonstrated by reverse transcription–polymerase chain reaction. To study BK signaling pathways, we employed fluorescent measurements of intracellular Ca2+, measured changes in extracellular pH as a reflection of Na+/H+ exchange (NHE with a Cytosensor microphysiometer, and assessed extracellular signal-regulated kinase (ERK activation by Western blotting.Results: Exposure to 100 nM of BK resulted in the rapid elevation of intracellular Ca2+, caused a ≥30% increase in NHE activity, and a ≥300% increase in ERK phosphorylation. All BK signals were blocked by HOE140, a BK B2 receptor antagonist, but not by a B1 receptor antagonist. Inhibitor studies suggest that BK-induced ERK activation requires phospholipase C and protein kinase C activities, and is Ca2+/calmodulin-dependent. The amiloride analog 5-(N-methyl-N-isobutyl-amiloride (MIA blocked short-term NHE activation and inhibited ERK phosphorylation, suggesting that NHE is critical for ERK activation by BK. BK induced an approximately 40% increase in the proliferation of A498 cells as assessed by bromodeoxyuridine uptake. This effect was blocked by the ERK inhibitor PD98059, and was dependent on NHE activity

  18. Epitope-based vaccines with the Anaplasma marginale MSP1a functional motif induce a balanced humoral and cellular immune response in mice.

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    Paula S Santos

    Full Text Available Bovine anaplasmosis is a hemoparasitic disease that causes considerable economic loss to the dairy and beef industries. Cattle immunized with the Anaplasma marginale MSP1 outer membrane protein complex presents a protective humoral immune response; however, its efficacy is variable. Immunodominant epitopes seem to be a key-limiting factor for the adaptive immunity. We have successfully demonstrated that critical motifs of the MSP1a functional epitope are essential for antibody recognition of infected animal sera, but its protective immunity is yet to be tested. We have evaluated two synthetic vaccine formulations against A. marginale, using epitope-based approach in mice. Mice infection with bovine anaplasmosis was demonstrated by qPCR analysis of erythrocytes after 15-day exposure. A proof-of-concept was obtained in this murine model, in which peptides conjugated to bovine serum albumin were used for immunization in three 15-day intervals by intraperitoneal injections before challenging with live bacteria. Blood samples were analyzed for the presence of specific IgG2a and IgG1 antibodies, as well as for the rickettsemia analysis. A panel containing the cytokines' transcriptional profile for innate and adaptive immune responses was carried out through qPCR. Immunized BALB/c mice challenged with A. marginale presented stable body weight, reduced number of infected erythrocytes, and no mortality; and among control groups mortality rates ranged from 15% to 29%. Additionally, vaccines have significantly induced higher IgG2a than IgG1 response, followed by increased expression of pro-inflammatory cytokines. This is a successful demonstration of epitope-based vaccines, and protection against anaplasmosis may be associated with elicitation of effector functions of humoral and cellular immune responses in murine model.

  19. Sumo and the cellular stress response

    OpenAIRE

    Enserink, Jorrit M.

    2015-01-01

    The ubiquitin family member Sumo has important functions in many cellular processes including DNA repair, transcription and cell division. Numerous studies have shown that Sumo is essential for maintaining cell homeostasis when the cell encounters endogenous or environmental stress, such as osmotic stress, hypoxia, heat shock, genotoxic stress, and nutrient stress. Regulation of transcription is a key component of the Sumo stress response, and multiple mechanisms have been described by which ...

  20. Combinatorial approaches to evaluate nanodiamond uptake and induced cellular fate

    Science.gov (United States)

    Eldawud, Reem; Reitzig, Manuela; Opitz, Jörg; Rojansakul, Yon; Jiang, Wenjuan; Nangia, Shikha; Zoica Dinu, Cerasela

    2016-02-01

    Nanodiamonds (NDs) are an emerging class of engineered nanomaterials that hold great promise for the next generation of bionanotechnological products to be used for drug and gene delivery, or for bio-imaging and biosensing. Previous studies have shown that upon their cellular uptake, NDs exhibit high biocompatibility in various in vitro and in vivo set-ups. Herein we hypothesized that the increased NDs biocompatibility is a result of minimum membrane perturbations and their reduced ability to induce disruption or damage during cellular translocation. Using multi-scale combinatorial approaches that simulate ND-membrane interactions, we correlated NDs real-time cellular uptake and kinetics with the ND-induced membrane fluctuations to derive energy requirements for the uptake to occur. Our discrete and real-time analyses showed that the majority of NDs internalization occurs within 2 h of cellular exposure, however, with no effects on cellular viability, proliferation or cellular behavior. Furthermore, our simulation analyses using coarse-grained models identified key changes in the energy profile, membrane deformation and recovery time, all functions of the average ND or ND-based agglomerate size. Understanding the mechanisms responsible for ND-cell membrane interactions could possibly advance their implementation in various biomedical applications.

  1. Rapid Cellular Identification by Dynamic Electromechanical Response

    Energy Technology Data Exchange (ETDEWEB)

    Nikiforov, Maxim [ORNL; Jesse, Stephen [ORNL; Kalinin, Sergei V [ORNL; Reukov, Vladimir V [ORNL; Vertegel, Alexey [ORNL; Thompson, Gary L [ORNL

    2009-01-01

    Coupling between electrical and mechanical phenomena is ubiquitous in living systems. Here, we demonstrate rapid identification of cellular organisms using difference in electromechanical activity in a broad frequency range. Principal component analysis of the dynamic electromechanical response spectra bundled with neural network based recognition provides a robust identification algorithm based on their electromechanical signature, and allows unambiguous differentiation of model Micrococcus Lysodeikticus and Pseudomonas Fluorescens system. This methodology provides a universal pathway for biological identification obviating the need for well-defined analytical models of Scanning Probe Microscopy response.

  2. Modeling In Vitro Cellular Responses to Silver Nanoparticles

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    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.

  3. Effect of cellular mobility on immune response

    Science.gov (United States)

    Pandey, R. B.; Mannion, R.; Ruskin, H. J.

    2000-08-01

    Mobility of cell types in our HIV immune response model is subject to an intrinsic mobility and an explicit directed mobility, which is governed by Pmob. We investigate how restricting the explicit mobility, while maintaining the innate mobility of a viral-infected cell, affects the model's results. We find that increasing the explicit mobility of the immune system cells leads to viral dominance for certain levels of viral mutation. We conclude that increasing immune system cellular mobility indirectly increases the virus’ inherent mobility.

  4. Cellular responses induced by environmental stress factors in Arctic Seabird chicks : Responses of the antioxidant defense system and autophagic lysosomal processes related to contaminant exposure and food restriction

    OpenAIRE

    Hegseth, Marit Nøst

    2011-01-01

    The papers of this thesis are not available in Munin: 1. Marit Nøst Hegseth, Lionel Camus, Lisa Bjørnsdatter Helgason, Raffaella Bocchetti, Geir Wing Gabrielsen and Francesco Regoli: 'Hepatic antioxidant responses related to levels of PCBs and metals in chicks of three Arctic seabird species', Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology (2011) 154: 28-35. Available at http://dx.doi.org/10.1016/j.cbpc.2011.02.008 2. Marit Nøst Hegseth, Lionel Camus, Stefania Go...

  5. Glafenine-induced intestinal injury in zebrafish is ameliorated by μ-opioid signaling via enhancement of Atf6-dependent cellular stress responses.

    Science.gov (United States)

    Goldsmith, Jason R; Cocchiaro, Jordan L; Rawls, John F; Jobin, Christian

    2013-01-01

    Beside their analgesic properties, opiates exert beneficial effects on the intestinal wound healing response. In this study, we investigated the role of μ-opioid receptor (MOR) signaling on the unfolded protein response (UPR) using a novel zebrafish model of NSAID-induced intestinal injury. The NSAID glafenine was administered to zebrafish larvae at 5 days post-fertilization (dpf) for up to 24 hours in the presence or absence of the MOR-specific agonist DALDA. By analysis with histology, transmission electron microscopy and vital dye staining, glafenine-treated zebrafish showed evidence of endoplasmic reticulum and mitochondrial stress, with disrupted intestinal architecture and halted cell stress responses, alongside accumulation of apoptotic intestinal epithelial cells in the lumen. Although the early UPR marker BiP was induced with glafenine-induced injury, downstream atf6 and s-xbp1 expression were paradoxically not increased, explaining the halted cell stress responses. The μ-opioid agonist DALDA protected against glafenine-induced injury through induction of atf6-dependent UPR. Our findings show that DALDA prevents glafenine-induced epithelial damage through induction of effective UPR. PMID:22917923

  6. Proteomic characterization of an isolated fraction of synthetic proteasome inhibitor (PSI-induced inclusions in PC12 cells might offer clues to aggresomes as a cellular defensive response against proteasome inhibition by PSI

    Directory of Open Access Journals (Sweden)

    Li Xing'an

    2010-08-01

    Full Text Available Abstract Background Cooperation of constituents of the ubiquitin proteasome system (UPS with chaperone proteins in degrading proteins mediate a wide range of cellular processes, such as synaptic function and neurotransmission, gene transcription, protein trafficking, mitochondrial function and metabolism, antioxidant defence mechanisms, and apoptotic signal transduction. It is supposed that constituents of the UPS and chaperone proteins are recruited into aggresomes where aberrant and potentially cytotoxic proteins may be sequestered in an inactive form. Results To determinate the proteomic pattern of synthetic proteasome inhibitor (PSI-induced inclusions in PC12 cells after proteasome inhibition by PSI, we analyzed a fraction of PSI-induced inclusions. A proteomic feature of the isolated fraction was characterized by identification of fifty six proteins including twenty previously reported protein components of Lewy bodies, twenty eight newly identified proteins and eight unknown proteins. These proteins, most of which were recognized as a profile of proteins within cellular processes mediated by the UPS, a profile of constituents of the UPS and a profile of chaperone proteins, are classed into at least nine accepted categories. In addition, prolyl-4-hydroxylase beta polypeptide, an endoplasmic reticulum member of the protein disulfide isomerase family, was validated in the developmental process of PSI-induced inclusions in the cells. Conclusions It is speculated that proteomic characterization of an isolated fraction of PSI-induced inclusions in PC12 cells might offer clues to appearance of aggresomes serving as a cellular defensive response against proteasome inhibition.

  7. Cellular and biochemical responses induced by Biotherapics prepared from intact influenza A (H3N2 and inactivated influenza A (H3N2 virus at 12x and 30x in the MDCK cells

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    Mariah Marcondes

    2011-09-01

    Full Text Available Biotherapics are homeopathic remedies prepared from organic products that are chemically undefined and can be used for treatment of diseases like influenza. There are several classes of biotherapics and, among these, there are some called "living biotherapics" or "Roberto Costa’s Biotherapics". This study aimed to compare the cellular and biochemical effects of biotherapics prepared from intact influenza virus diluted in water and the one obtained from the same viral sample inactivated by ethanol 70% (v / v, both in the potencies of 12x and 30x. Transmission electron microscopy (TEM analyses were performed on both preparations to assess the integrity of viral particles, which showed that ethanol 70% (v/v induced a complete denaturation of viral particles. In contrast, the integrity of virus particles was preserved when water was used as the biotherapic solvent. Cellular and biochemical alterations induced by the preparations on MDCK cells were analyzed and compared with those induced by respective controls (water 30x-treated and untreated cells. Cellular viability analyzed by MTT method showed statistically significant differences (p <0.05 in MDCK cells treated with intact biotherapic for 5 (3 stimuli and 30 (18 stimuli days in comparison with untreated control. TEM analysis did not show significant cellular changes when the different experimental groups were compared. The enzymatic activity of phosphofructokinase 1 (PFK, an important enzyme in the glycolytic pathway, presented a statistically significant increase (p <0.05 after 30 days of treatment when compared to control groups. The results obtained suggest that inactivation of viral sample with ethanol 70% induces lysis and disruption of viral particles. In addition, preliminary results indicated that treatment with intact biotherapic seems to induce higher variations on MDCK cells responses when compared to inactivated-biotherapic-treated cells. Further analyses are ongoing

  8. Metal-induced stress in bivalves living along a gradient of Cd contamination: relating sub-cellular metal distribution to population-level responses

    International Nuclear Information System (INIS)

    The use of biomarkers to assess the impacts of contaminants on aquatic ecosystems has noticeably increased over the past few years. Few of these studies, however, have contributed to the prediction of ecologically significant effects (i.e., at the population or community levels). The present field study was designed to evaluate the potential of metallothionein (MT) and sub-cellular metal partitioning measurements for predicting toxic effects at higher levels of the biological organization in freshwater bivalves (Pyganodon grandis) chronically exposed to Cd. For that purpose, we quantitatively sampled P. grandis populations in the littoral zone of nine lakes on the Precambrian Canadian Shield during two consecutive summers (1998 and 1999); lakes were characterized by contrasting Cd levels but similar trophic status. We tested relationships between the population status of P. grandis (i.e., growth parameters, density, biomass, secondary production, turnover ratio and cumulative fecundity) and (i) ambient Cd concentrations, (ii) sub-organismal responses (MT concentrations in the gill cytosol of individuals and Cd concentrations in three metal-ligand pools identified as M-HMW, the high molecular weight pool, M-MT, the metallothionein-like pool and M-LMW, the low molecular weight pool) and (iii) ecological confounding factors (food resources, presence of host fishes for the obligatory parasitic larval stage of P. grandis). Our results show that littoral density, live weight, dry viscera biomass, production and cumulative fecundity decreased with increasing concentrations of the free-cadmium ion in the environment (Pearson's r ranging from -0.63 to -0.78). On the other hand, theoretical maximum shell lengths (L∞) in our populations were related to both the dissolved Ca concentration and food quality (sestonic C and N concentrations). Overall, Cd concentrations in the gill cytosolic HMW pool of the individual molluscs were the biomarker response that was most frequently

  9. Repair and mutagenesis in procaryotes as cellular responses to ambiental agents

    International Nuclear Information System (INIS)

    The correct and incorrect mechanisms of DNA repair are discussed, as well as the cellular responses induced by the DNA lesions; the reductone mollecular effects; the cellular interactions among irradiated populations of microorganisms and the utilization of microbial assays for the detection of oncogenic activities of chemicals. (M.A.)

  10. Silymarin Suppresses Cellular Inflammation By Inducing Reparative Stress Signaling

    Energy Technology Data Exchange (ETDEWEB)

    Lovelace, Erica S.; Wagoner, Jessica; MacDonald, James; Bammler, Theo; Bruckner, Jacob; Brownell, Jessica; Beyer, Richard; Zink, Erika M.; Kim, Young-Mo; Kyle, Jennifer E.; Webb-Robertson, Bobbie-Jo M.; Waters, Katrina M.; Metz, Thomas O.; Farin, Federico; Oberlies, Nicholas H.; Polyak, Steve

    2015-08-28

    Silymarin (SM), a natural product, is touted as a liver protectant and preventer of both chronic inflammation and diseases. To define how SM elicits these effects at a systems level, we performed transcriptional profiling, metabolomics, and signaling studies in human liver and T cell lines. Multiple pathways associated with cellular stress and metabolism were modulated by SM treatment within 0.5 to four hours: activation of Activating Transcription Factor 4 (ATF-4) and adenosine monophosphate protein kinase (AMPK) and inhibition of mammalian target of rapamycin (mTOR) signaling, the latter being associated with induction of DNA-damage-inducible transcript 4 (DDIT4). Metabolomics analyses revealed suppression of glycolytic, TCA cycle, and amino acid metabolism by SM treatment. Antiinflammatory effects arose with prolonged (i.e. 24 hours) SM exposure, with suppression of multiple proinflammatory mRNAs and nuclear factor kappa B (NF-κB) and forkhead box O (FOXO) signaling. Studies with murine knock out cells revealed that SM inhibition of both mTOR and NF-κB was partially AMPK dependent, while SM inhibition of the mTOR pathway in part required DDIT4. Thus, SM activates stress and repair responses that culminate in an anti-inflammatory phenotype. Other natural products induced similar stress responses, which correlated with their ability to suppress inflammation. Therefore, natural products like SM may be useful as tools to define how metabolic, stress, and repair pathways regulate cellular inflammation.

  11. Cellular Stress Response to Engineered Nanoparticles: Effect of Size, Surface Coating, and Cellular Uptake

    Science.gov (United States)

    CELLULAR STRESS RESPONSE TO ENGINEERED NANOPARTICLES: EFFECT OF SIZE, SURFACE COATING, AND CELLULAR UPTAKE RY Prasad 1, JK McGee2, MG Killius1 D Ackerman2, CF Blackman2 DM DeMarini2 , SO Simmons2 1 Student Services Contractor, US EPA, RTP, NC 2 US EPA, RTP, NC The num...

  12. Cellular immune response following pre-exposure and postexposure rabies vaccination by intradermal and intramuscular routes

    OpenAIRE

    Venkataswamy, Manjunatha Muniswamappa; Madhusudana, Shampur Narayan; Sanyal, Sampada Sudarshan; Taj, Shaheen; Belludi, Ashwin Yajaman; Mani, Reeta Subramaniam; Hazra, Nandita

    2015-01-01

    Purpose Immunization against rabies in humans induces protective neutralizing antibodies; however, the induction of type 1 or type 2 cytokine mediated cellular immune responses following rabies vaccination is not understood. Hence, the present study investigated cellular cytokine responses in vaccinated individuals. Materials and Methods The study groups included healthy rabies antigen naive controls (n=10), individuals who received intradermal primary (n=10) or booster pre-exposure vaccinati...

  13. Phenylbutyric acid induces the cellular senescence through an Akt/p21WAF1 signaling pathway

    International Nuclear Information System (INIS)

    Highlights: ► Phenylbutyric acid induces cellular senescence. ► Phenylbutyric acid activates Akt kinase. ► The knockdown of PERK also can induce cellular senescence. ► Akt/p21WAF1 pathway activates in PERK knockdown induced cellular senescence. -- Abstract: It has been well known that three sentinel proteins – PERK, ATF6 and IRE1 – initiate the unfolded protein response (UPR) in the presence of misfolded or unfolded proteins in the ER. Recent studies have demonstrated that upregulation of UPR in cancer cells is required to survive and proliferate. Here, we showed that long exposure to 4-phenylbutyric acid (PBA), a chemical chaperone that can reduce retention of unfolded and misfolded proteins in ER, induced cellular senescence in cancer cells such as MCF7 and HT1080. In addition, we found that treatment with PBA activates Akt, which results in p21WAF1 induction. Interestingly, the depletion of PERK but not ATF6 and IRE1 also induces cellular senescence, which was rescued by additional depletion of Akt. This suggests that Akt pathway is downstream of PERK in PBA induced cellular senescence. Taken together, these results show that PBA induces cellular senescence via activation of the Akt/p21WAF1 pathway by PERK inhibition.

  14. Early cellular signaling responses to axonal injury

    Directory of Open Access Journals (Sweden)

    Wang Ai

    2009-03-01

    Full Text Available Abstract Background We have used optic nerve injury as a model to study early signaling events in neuronal tissue following axonal injury. Optic nerve injury results in the selective death of retinal ganglion cells (RGCs. The time course of cell death takes place over a period of days with the earliest detection of RGC death at about 48 hr post injury. We hypothesized that in the period immediately following axonal injury, there are changes in the soma that signal surrounding glia and neurons and that start programmed cell death. In the current study, we investigated early changes in cellular signaling and gene expression that occur within the first 6 hrs post optic nerve injury. Results We found evidence of cell to cell signaling within 30 min of axonal injury. We detected differences in phosphoproteins and gene expression within the 6 hrs time period. Activation of TNFα and glutamate receptors, two pathways that can initiate cell death, begins in RGCs within 6 hrs following axonal injury. Differential gene expression at 6 hrs post injury included genes involved in cytokine, neurotrophic factor signaling (Socs3 and apoptosis (Bax. Conclusion We interpret our studies to indicate that both neurons and glia in the retina have been signaled within 30 min after optic nerve injury. The signals are probably initiated by the RGC soma. In addition, signals activating cellular death pathways occur within 6 hrs of injury, which likely lead to RGC degeneration.

  15. The Cellular Bases of Antibody Responses during Dengue Virus Infection

    Science.gov (United States)

    Yam-Puc, Juan Carlos; Cedillo-Barrón, Leticia; Aguilar-Medina, Elsa Maribel; Ramos-Payán, Rosalío; Escobar-Gutiérrez, Alejandro; Flores-Romo, Leopoldo

    2016-01-01

    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 such as 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. PMID:27375618

  16. 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.

  17. P53 family and cellular stress responses in cancer

    Directory of Open Access Journals (Sweden)

    Johanna ePflaum

    2014-10-01

    Full Text Available p53 is an important tumor suppressor gene, which is stimulated by cellular stress like ionizing radiation, hypoxia, carcinogens and oxidative stress. Upon activation p53 leads to cell cycle arrest and promotes DNA repair or induces apoptosis via several pathways. p63 and p73 are structural homologs of p53 that can act similarly to the protein but also hold functions distinct from p53. Today more than forty different isoforms of the p53 family members are known. They result from transcription via different promoters and alternative splicing. Some isoforms have carcinogenic properties and mediate resistance to chemotherapy. Therefore, expression patterns of the p53 family genes can offer prognostic information in several malignant tumors. Furthermore, the p53 family constitutes a potential target for cancer therapy. Small molecules (e.g. Nutlins, RITA, PRIMA-1, and MIRA-1 among others have been objects of intense research interest in recent years. They restore pro-apoptotic wild-type p53 function and were shown to break chemotherapeutic resistance. Due to p53 family interactions small molecules also influence p63 and p73 activity. Thus, the members of the p53 family are key players in the cellular stress response in cancer and are expected to grow in importance as therapeutic targets.

  18. Molecular events basic to cellular radiation response

    International Nuclear Information System (INIS)

    The initiation and control of the division process in normal cells is studied to gain insight into changes in these regards caused by x-irradiation and neoplasia. The Primer Hypothesis for eukaryotic gene regulation proposes that small molecular weight RNA acts as primer for new RNA synthesis by hybridizing with DNA and there initiating the transcription of a new RNA chain. The experiments reported here indicate that small molecular weight RNA will induce the production of new proteins. These results are consistent with the Primer Hypothesis, and demonstrate that RNA can be taken up from the media by cells in culture and can induce in vitro the production of differentiated cell products

  19. Cellular responses of BRCA1-defective and triple-negative breast cancer cells and in vitro BRCA1 interactions induced by metallo-intercalator ruthenium(II) complexes containing chloro-substituted phenylazopyridine

    International Nuclear Information System (INIS)

    Triple-negative breast cancer (TNBC) is defined by the absence of expression of estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2. Breast cancers with a BRCA1 mutation are also frequently triple-negative. Currently, there is a lack of effective therapies and known specific molecular targets for this aggressive breast cancer subtype. To address this concern, we have explored the cellular responses of BRCA1-defective and triple-negative breast cancer cells, and in vitro BRCA1 interactions induced by the ruthenium(II) complexes containing the bidentate ligand, 5-chloro-2-(phenylazo)pyridine. Triple-negative MDA-MB-231, BRCA1-defective HCC1937 and BRCA1-competent MCF-7 breast cancer cell lines were treated with ruthenium(II) complexes. The cytoxoxicity of ruthenium-induced breast cancer cells was evaluated by a real time cellular analyzer (RTCA). Cellular uptake of ruthenium complexes was determined by ICP-MS. Cell cycle progression and apoptosis were assessed using propidium iodide and Annexin V flow cytometry. The N-terminal BRCA1 RING protein was used for conformational and functional studies using circular dichroism and in vitro ubiquitination. HCC1937 cells were significantly more sensitive to the ruthenium complexes than the MDA-MB-231 and MCF-7 cells. Treatment demonstrated a higher degree of cytotoxicity than cisplatin against all three cell lines. Most ruthenium atoms were retained in the nuclear compartment, particularly in HCC1937 cells, after 24 h of incubation, and produced a significant block at the G2/M phase. An increased induction of apoptotic cells as well as an upregulation of p53 mRNA was observed in all tested breast cancer cells. It was of interest that BRCA1 mRNA and replication of BRCA1-defective cells were downregulated. Changes in the conformation and binding constants of ruthenium-BRCA1 adducts were observed, causing inactivation of the RING heterodimer BRCA1/BARD1-mediated E3 ubiquitin ligase activity

  20. Molecular events basic to cellular radiation response

    Energy Technology Data Exchange (ETDEWEB)

    Kolodny, G. M.

    1979-09-01

    The initiation and control of the division process in normal cells is studied to gain insight into changes in these regards caused by x-irradiation and neoplasia. The Primer Hypothesis for eukaryotic gene regulation proposes that small molecular weight RNA acts as primer for new RNA synthesis by hybridizing with DNA and there initiating the transcription of a new RNA chain. The experiments reported here indicate that small molecular weight RNA will induce the production of new proteins. These results are consistent with the Primer Hypothesis, and demonstrate that RNA can be taken up from the media by cells in culture and can induce in vitro the production of differentiated cell products. (ACR)

  1. Summarizing cellular responses as biological process networks

    OpenAIRE

    Lasher, Christopher D; Rajagopalan, Padmavathy; Murali, T.M.

    2013-01-01

    Abstract Background Microarray experiments can simultaneously identify thousands of genes that show significant perturbation in expression between two experimental conditions. Response networks, computed through the integration of gene interaction networks with expression perturbation data, may themselves contain tens of thousands of interactions. Gene set enrichment has become standard for summarizing the results of these analyses in te...

  2. Elucidation of lead-induced oxidative stress in Talinum triangulare roots by analysis of antioxidant responses and DNA damage at cellular level.

    Science.gov (United States)

    Kumar, Abhay; Prasad, M N V; Mohan Murali Achary, V; Panda, Brahma B

    2013-07-01

    Hydroponic experiments were performed with Talinum triangulare (Jacq.) Willd. focusing the root cellular biochemistry with special emphasis on DNA damage, structural, and elemental analyses in Pb(NO3)2 exposed with 0, 0.25, 0.5, 0.75, 1.0, and 1.25 mM for 7 days. Lead (Pb) increased reactive oxygen species production, lipid peroxidation, protein oxidation, cell death, and DNA damage and decreased the protein content in a dose-dependent manner. Likewise, a dose-dependent induction of antioxidative enzymes superoxide dismutase and catalase by Pb was evident. Ascorbate peroxidase on the other hand responded biphasically to Pb treatments by showing induction at low (0.25 and 0.50) and repression at high (0.75-1.25 mM) concentrations. The estimation of proline content also indicated a similar biphasic trend. Scanning electron microscope and energy-dispersive X-ray spectroscopy analysis showed that 1.25 mM Pb treatment resulted in ultrastructural modifications in roots and stem tissue that was marked by the change in the elemental profile. The findings pointed to the role of oxidative stress in the underlying Pb phytotoxicity and genotoxicity in T. triangulare. PMID:23263755

  3. Peroxisomes are platforms for cytomegalovirus’ evasion from the cellular immune response

    OpenAIRE

    Magalhães, Ana Cristina; Ferreira, Ana Rita; Gomes, Sílvia; Vieira, Marta; Gouveia, Ana; Valença, Isabel; Islinger, Markus; Nascimento, Rute; Schrader, Michael; Kagan, Jonathan C.; Ribeiro, Daniela

    2016-01-01

    The human cytomegalovirus developed distinct evasion mechanisms from the cellular antiviral response involving vMIA, a virally-encoded protein that is not only able to prevent cellular apoptosis but also to inhibit signalling downstream from mitochondrial MAVS. vMIA has been shown to localize at mitochondria and to trigger their fragmentation, a phenomenon proven to be essential for the signalling inhibition. Here, we demonstrate that vMIA is also localized at peroxisomes, induces their fragm...

  4. Expression of MPB83 from Mycobacterium bovis in Brucella abortus S19 induces specific cellular immune response against the recombinant antigen in BALB/c mice.

    Science.gov (United States)

    Sabio y García, Julia V; Bigi, Fabiana; Rossetti, Osvaldo; Campos, Eleonora

    2010-12-01

    Immunodominant MPB83 antigen from Mycobacterium bovis was expressed as a chimeric protein fused to either β-galactosidase, outer membrane lipoprotein OMP19 or periplasmic protein BP26 in gram-negative Brucella abortus S19, in all cases driven by each gene's own promoter. All fusion proteins were successfully expressed and localized in the expected subcellular fraction. Moreover, OMP19-MPB83 was processed as a lipoprotein when expressed in B. abortus. Splenocytes from BALB/c mice immunized with the recombinant S19 strains carrying the genes coding for the heterologous antigens in replicative plasmids, showed equally specific INF-γ production in response to MPB83 stimulation. Association to the lipid moiety of OMP19 presented no advantage in terms of immunogenicity for MPB83. In contrast, fusion to BP26, which was encoded by an integrative plasmid, resulted in a weaker immune response. None of the constructions affected the survival rate or the infection pattern of Brucella. We concluded that B. abortus S19 is an appropriate candidate for the expression of M. bovis antigens both associated to the membrane or cytosolic fraction and may provide the basis for a future combined vaccine for bovine brucellosis and tuberculosis. PMID:20888425

  5. Investigation of cellular responses upon interaction with silver nanoparticles

    Directory of Open Access Journals (Sweden)

    Subbiah R

    2015-08-01

    Full Text Available Ramesh Subbiah,1,2 Seong Beom Jeon,3,4 Kwideok Park,1,2 Sang Jung Ahn,4,5 Kyusik Yun3 1Center for Biomaterials, Korea Institute of Science and Technology, Seoul, 2Department of Biomedical Engineering, Korea University of Science and Technology, Daejon, 3Department of Bionanotechnology, Gachon University, Gyeonggi-do, 4Centre for Advanced Instrumentation, Korea Research Institute of Standard and Science, 5Major of Nano Science, Korea University of Science and Technology, Daejeon, Republic of Korea Abstract: In order for nanoparticles (NPs to be applied in the biomedical field, a thorough investigation of their interactions with biological systems is required. Although this is a growing area of research, there is a paucity of comprehensive data in cell-based studies. To address this, we analyzed the physicomechanical responses of human alveolar epithelial cells (A549, mouse fibroblasts (NIH3T3, and human bone marrow stromal cells (HS-5, following their interaction with silver nanoparticles (AgNPs. When compared with kanamycin, AgNPs exhibited moderate antibacterial activity. Cell viability ranged from ≤80% at a high AgNPs dose (40 µg/mL to >95% at a low dose (10 µg/mL. We also used atomic force microscopy-coupled force spectroscopy to evaluate the biophysical and biomechanical properties of cells. This revealed that AgNPs treatment increased the surface roughness (P<0.001 and stiffness (P<0.001 of cells. Certain cellular changes are likely due to interaction of the AgNPs with the cell surface. The degree to which cellular morphology was altered directly proportional to the level of AgNP-induced cytotoxicity. Together, these data suggest that atomic force microscopy can be used as a potential tool to develop a biomechanics-based biomarker for the evaluation of NP-dependent cytotoxicity and cytopathology. Keywords: AFM, roughness, nanoindentation, biomarker, cytotoxicity, biomechanics

  6. WORTMANNIN affect cellular response by radiation

    International Nuclear Information System (INIS)

    Objective: To observe radiation Response of cells by WORTMANNIN (WT), which is inhibitor for Phosphatidylinositol-3 Kinase (PI-3K). Methods: LP3 cells are prepared with different concentration of WT for 1 hour and receive different dose γ irradiation. To continue the cell for clone culture, and get the production of dose-survival curve. 1800 pulsed-field gel electrophoresis is used to detect DNA double-strand breaks after the 20 Gy γ irradiation. Continue to use the mobility shift assays (Electrophoresis Mobility Shift Assay, EMSA) to observe NF-kB transcription factor of the corresponding changes. Result: WT can be found to increase the radiation sensitivity of SP3 cells, the best sensitizer concentration in 20 μmol /L or more, obvious sensitizing effect within 6 h time; the electrophoresis experiments showed that after irradiation with time, by 50 μmol /L WT group DNA the gel is higher than that of the simple exposure group; transcription factor NF-kB binding activity in the 6 hours after exposure experiences a low-rise and then the process of rising with its the peak of the change reaching after about 3 hours after irradiation. Conclusion: It suggests the existence of PI-3K-mediated radiation sensitizer pathways. Ionizing radiation may activate NF-kB, which caused some DNA damage repair and other defense mechanisms and cell-related gene activity in order to reduce radiation damage. WT may block this process through the early stages of radiation-sensitizing effect. (authors)

  7. New insights into the cellular response to radiation using microbeams

    Science.gov (United States)

    Folkard, Melvyn; Prise, Kevin; Schettino, Giuseppe; Shao, Chunlin; Gilchrist, Stuart; Vojnovic, Boris

    2005-04-01

    Micro-irradiation techniques continue to be highly relevant to a number of radiobiological studies, due to their ability to deliver precise doses of radiation to selected individual cells (or sub-cellular targets) in vitro. The Gray cancer institute (GCI) ion microbeam uses a 1 μm diameter bore glass capillary to vertically collimate protons, or helium ions accelerated by a 4 MV Van de Graaff. Using 3He2+ ions, 99% of cells are targeted with an accuracy of ±2 μm, and with a particle counting accuracy >99%. Using automated cell finding and irradiation procedures, up to 10,000 cells per hour can be individually irradiated. Microbeams are now being used to study a number of novel 'non-targeted' responses that do not follow the standard radiation model based on direct DNA damage and are now known to occur when living cells and tissues are irradiated. One such response is the so-called 'bystander effect' where unirradiated cells are damaged through signalling pathways initiated by a nearby irradiated cell. This effect predominates at low doses and profoundly challenges our understanding of environmental radiation risk. Furthermore, we now have evidence that simple molecules (such as nitric oxide) are involved in the signalling process, such that it may be possible to chemically influence the bystander response. If so, then this could eventually lead to improvements in the treatment of cancer by radiotherapy. Other studies have shown that the bystander effect is induced with equal effectiveness if either the nucleus or the cytoplasm of a cell is targeted.

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

    International Nuclear Information System (INIS)

    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.

  9. Exercise Prevents Diet-Induced Cellular Senescence in Adipose Tissue.

    Science.gov (United States)

    Schafer, Marissa J; White, Thomas A; Evans, Glenda; Tonne, Jason M; Verzosa, Grace C; Stout, Michael B; Mazula, Daniel L; Palmer, Allyson K; Baker, Darren J; Jensen, Michael D; Torbenson, Michael S; Miller, Jordan D; Ikeda, Yasuhiro; Tchkonia, Tamara; van Deursen, Jan M; Kirkland, James L; LeBrasseur, Nathan K

    2016-06-01

    Considerable evidence implicates cellular senescence in the biology of aging and chronic disease. Diet and exercise are determinants of healthy aging; however, the extent to which they affect the behavior and accretion of senescent cells within distinct tissues is not clear. Here we tested the hypothesis that exercise prevents premature senescent cell accumulation and systemic metabolic dysfunction induced by a fast-food diet (FFD). Using transgenic mice that express EGFP in response to activation of the senescence-associated p16(INK4a) promoter, we demonstrate that FFD consumption causes deleterious changes in body weight and composition as well as in measures of physical, cardiac, and metabolic health. The harmful effects of the FFD were associated with dramatic increases in several markers of senescence, including p16, EGFP, senescence-associated β-galactosidase, and the senescence-associated secretory phenotype (SASP) specifically in visceral adipose tissue. We show that exercise prevents the accumulation of senescent cells and the expression of the SASP while nullifying the damaging effects of the FFD on parameters of health. We also demonstrate that exercise initiated after long-term FFD feeding reduces senescent phenotype markers in visceral adipose tissue while attenuating physical impairments, suggesting that exercise may provide restorative benefit by mitigating accrued senescent burden. These findings highlight a novel mechanism by which exercise mediates its beneficial effects and reinforces the effect of modifiable lifestyle choices on health span. PMID:26983960

  10. Dose dependent rearrangement of cellular membranes induced by ionizing radiation

    International Nuclear Information System (INIS)

    The radiation-induced effects at dose rate of 0.35 Gy/min (in vivo) and of ultra-low doses (in vitro) on the cell membranes structural state were shown. The modifications of the membrane protein and lipid components and their dynamic state were revealed at experimental irradiation conditions by fluorescent probe analysis. The principal component analysis of the research data indicates the dose-dependent decrease of plasma membrane structural orderliness of the small intestine enterocytes with the increase of the ionizing irradiation acute dose of 0.5, 1.0, 2.0, 3.0 Gy at dose rate of 0.35 Gy/min. The complex response of the biological structure - the erythrocytes plasma membrane, on the ionizing radiation action at ultra-low doses that occurred through macromolecular structural rearrangements was also demonstrated. The features of the structural rearrangement of the cellular membranes depending on the ionizing radiation dose (dose rate) are found out

  11. 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...

  12. Cellular Mechanisms of L-arginine Induced Experimental Acute Pancreatitis

    OpenAIRE

    Masood, Omar

    2013-01-01

    AbstractThe University Of ManchesterOmar MasoodMD Thesis 2013Cellular Mechanisms of L-arginine Induced Experimental Acute Pancreatitis. IntroductionImpairment of cytosolic calcium ([Ca2+]i) signaling and in particular calcium overload has emerged as a possible unifying mechanism for precipitating acute pancreatitis (AP.)In the L-arginine (L-arg) experimental model of AP, nitric oxide (NO) has been implicated however the disease progression is largely unaffected by nitric oxide synthase (NOS) ...

  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. 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.

  15. Extended abstracts: Microbeam Probes of Cellular Radiation Response [final report

    International Nuclear Information System (INIS)

    In July 1999, we organized the 4th International Workshop: Microbeam Probes of Cellular Radiation Response, held in Killiney Bay, Dublin, Ireland, on July 17-18. Roughly 75 scientists (about equal numbers of physicists and biologists) attended the workshop, the fourth in a bi-annual series. Extended abstracts from the meeting were published in the Radiation Research journal, vol. 153, iss. 2, pp. 220-238 (February 2000)(attached). All the objectives in the proposal were met

  16. Ubiquitin Metabolism Affects Cellular Response to Volatile Anesthetics in Yeast

    OpenAIRE

    Wolfe, Darren; Reiner, Thomas; Keeley, Jessica L.; Pizzini, Mark; Keil, Ralph L.

    1999-01-01

    To investigate the mechanism of action of volatile anesthetics, we are studying mutants of the yeast Saccharomyces cerevisiae that have altered sensitivity to isoflurane, a widely used clinical anesthetic. Several lines of evidence from these studies implicate a role for ubiquitin metabolism in cellular response to volatile anesthetics: (i) mutations in the ZZZ1 gene render cells resistant to isoflurane, and the ZZZ1 gene is identical to BUL1 (binds ubiquitin ligase), which appears to be invo...

  17. Glucose supplement reverses the fasting-induced suppression of cellular immunity in Mongolian gerbils (Meriones unguiculatus).

    Science.gov (United States)

    Xu, De-Li; Wang, De-Hua

    2011-10-01

    Glucose plays an important role in immunity. Three day fasting will decrease cellular immunity and blood glucose levels in Mongolian gerbils (Meriones unguiculatus). In the present study, we tested the hypothesis that glucose supplement can reverse the fasting-induced suppression in cellular immunity in gerbils. Twenty-eight male gerbils were selected and randomly divided into fed and fasting groups. Half of the gerbils in each group were then provided with either 10% glucose water or pure water. After 66 h, each gerbil was injected with phytohaemagglutinin (PHA) solution to challenge cellular immunity. Results showed that glucose supplement restored blood glucose levels in fasted gerbils to those of the fed controls. It also recovered cellular immunity, body fat mass and serum leptin levels in fasted gerbils to the values of the fed controls. Blood glucose levels were positively correlated with body fat mass, leptin levels and cellular immune responses. Thymus and spleen masses, and white blood cells in fasted gerbils were not affected by glucose supplement. In general, our data demonstrate that glucose supplement could reverse fasting-induced suppression of cellular immunity in Mongolian gerbils. PMID:21885265

  18. HBV和HIV的复合型DNA免疫可诱发BALB/c小鼠的细胞免疫应答%Vaccination of BALB/c Mice with Chimeric HBV and HIV DNA can Induce Cellular Immune Responses

    Institute of Scientific and Technical Information of China (English)

    和绍清; 董承红; 孙明; 李琦涵

    2001-01-01

    本研究是通过细胞免疫检测来研究含有两种不同病毒基因的复合型DNA免疫的效果,同时和单一病毒基因的DNA免疫作比较。在本实验中,将HBV的S基因和(或)HⅣ-1的gp120基因插入到真核表达载体pcDNA3中,得到能表达HBsAg和gp120融合蛋白的重组体pcDNA-S-120,和能表达HBsAg的重组体pcDNA-S。在实验中,将重组质粒DNA直接注射到BALB/c小鼠股四头肌内,按每只小鼠100μg/100μl的剂量经3次免疫后,在T细胞增殖实验中,用HBsAg蛋白刺激体外培养的被免疫小鼠T细胞后,出现了明显的T细胞增殖。采用”cr释放法检测特异性CTL杀伤作用时,发现致敏的CTL对HIV gp120多肽孵育后的靶细胞P815有明显的杀伤作用。%Recent studies support the notion that vaccination with plasmid DNA encording genes for viral or bacterial antigens can elicite both humoral and cellular immune responses in rodents and non-human primates, but their major advantage at immunologic level are their capacity to induce antigen-specific CD8 + T cell responses. In the present study,BALB/c mice were immunilized intramuscularly with recombinant plasmid pcDNA-S-120 in which the S gene of HBV and gp120 gene of HIV-1 were cloned into pcDNA3 in fusion form, and also with pcDNA-S in which the S gene of HBV had been cloned into pcDNA3. Mice were immunilized 3 times with 100 μg/100 μi per mouse. In the T cell proliferation assays, it was showed that T cells proliferated in vitro obviously after stimulation with pcDNA-S and pcDNA-S-120. The sensitized CTL could specifically kill the target cell P815 which were pulsed by 10-AA peptide of HIV. It concludes that cellular immune responses could be elicited in the experimental animals after direct injections of recombinatant plasmid DNA in which the S gene and gp120 gene were cloned in fusion form.

  19. Involvement of oxygen reactive species in the cellular response of carcinoma cells to irradiation

    International Nuclear Information System (INIS)

    After a presentation of oxygen reactive species and their sources, the author describes the enzymatic and non-enzymatic anti-oxidative defenses, the physiological roles of oxygen reactive species, the oxidative stress, the water radiolysis, the anti-oxidative enzymes and the effects of ionizing radiations. The author then reports an investigation on the contribution of oxygen reactive species in the cellular response to irradiation, and an investigation on the influence of the breathing chain on the persistence of a radio-induced oxidative stress. He also reports a research on molecular mechanisms involved in the cellular radio-sensitivity

  20. Cellular automaton model of cell response to targeted radiation

    International Nuclear Information System (INIS)

    It has been shown that the response of cells to low doses of radiation is not linear and cannot be accurately extrapolated from the high dose response. To investigate possible mechanisms involved in the behaviour of cells under very low doses of radiation, a cellular automaton (CA) model was created. The diffusion and consumption of glucose in the culture dish were computed in parallel to the growth of cells. A new model for calculating survival probability was introduced; the communication between targeted and non-targeted cells was also included. Early results on the response of non-confluent cells to targeted irradiation showed the capability of the model to take account for the non-linear response in the low-dose domain

  1. Phenylbutyric acid induces the cellular senescence through an Akt/p21{sup WAF1} signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hag Dong [Laboratory of Biochemistry, School of Life Sciences and Biotechnology, and BioInstitute, Korea University, Seoul 136-701 (Korea, Republic of); Jang, Chang-Young [Research Center for Cell Fate Control, College of Pharmacy, Sookmyung Women' s University, Seoul 140-742 (Korea, Republic of); Choe, Jeong Min [Laboratory of Biochemistry, School of Life Sciences and Biotechnology, and BioInstitute, Korea University, Seoul 136-701 (Korea, Republic of); Department of Biochemistry, Korea University College of Medicine, Seoul 136-705 (Korea, Republic of); Korean Institute of Molecular Medicine and Nutrition, Seoul 136-705 (Korea, Republic of); Sohn, Jeongwon, E-mail: biojs@korea.ac.kr [Department of Biochemistry, Korea University College of Medicine, Seoul 136-705 (Korea, Republic of); Korean Institute of Molecular Medicine and Nutrition, Seoul 136-705 (Korea, Republic of); Kim, Joon, E-mail: joonkim@korea.ac.kr [Laboratory of Biochemistry, School of Life Sciences and Biotechnology, and BioInstitute, Korea University, Seoul 136-701 (Korea, Republic of)

    2012-06-01

    Highlights: Black-Right-Pointing-Pointer Phenylbutyric acid induces cellular senescence. Black-Right-Pointing-Pointer Phenylbutyric acid activates Akt kinase. Black-Right-Pointing-Pointer The knockdown of PERK also can induce cellular senescence. Black-Right-Pointing-Pointer Akt/p21{sup WAF1} pathway activates in PERK knockdown induced cellular senescence. -- Abstract: It has been well known that three sentinel proteins - PERK, ATF6 and IRE1 - initiate the unfolded protein response (UPR) in the presence of misfolded or unfolded proteins in the ER. Recent studies have demonstrated that upregulation of UPR in cancer cells is required to survive and proliferate. Here, we showed that long exposure to 4-phenylbutyric acid (PBA), a chemical chaperone that can reduce retention of unfolded and misfolded proteins in ER, induced cellular senescence in cancer cells such as MCF7 and HT1080. In addition, we found that treatment with PBA activates Akt, which results in p21{sup WAF1} induction. Interestingly, the depletion of PERK but not ATF6 and IRE1 also induces cellular senescence, which was rescued by additional depletion of Akt. This suggests that Akt pathway is downstream of PERK in PBA induced cellular senescence. Taken together, these results show that PBA induces cellular senescence via activation of the Akt/p21{sup WAF1} pathway by PERK inhibition.

  2. 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. PMID:26792848

  3. Investigation of the Cellular and Molecular Mechanisms of Radiation-induced Bystander Effects

    OpenAIRE

    Furlong, Hayley

    2014-01-01

    The overall aim of this study was to investigate the cellular and molecular mechanisms involved in radiation-induced bystander effects in HaCaT cells, predominantly at low-doses of irradiation. They do not follow the original dose-response theory and exhibit a unique cascade of signalling events, which are under intense investigation for radiation risk purposes. An in vitro system was first used to observe the bystander effect, comparing two cell viability assays while measuring apoptotic cel...

  4. Cellular automata simulation of medication-induced autoimmune diseases

    Science.gov (United States)

    Stauffer, Dietrich; Proykova, Ana

    2004-01-01

    We implement the cellular automata model proposed by Stauffer and Weisbuch in 1992 to describe the response of the immune system to antigens in the presence of medications. The model contains two thresholds, θ1 and θ2, suggested by de Boer, Segel, and Perelson to present the minimum field needed to stimulate the proliferation of the receptors and to suppress it, respectively. The influence of the drug is mimicked by increasing the second threshold, thus enhancing the immune response. If this increase is too strong, the immune response is triggered in the whole immune repertoire, causing it to attack the own body. This effect is seen in our simulations to depend both on the ratio of the thresholds and on their absolute values.

  5. Cellular Bases of Light-regulated Gravity Responses

    Science.gov (United States)

    Roux, Stanley J.

    2003-01-01

    This report summarizes the most significant research accomplished in our NAG2-1347 project on the cellular bases of light-regulated gravity responses, It elaborates mainly on our discovery of the role of calcium currents in gravity-directed polar development in single germinating spore cells of the fern Ceratopteris, our development of RNA silencing as a viable method of suppressing the expression of specific genes in Ceratopteris, and on the structure, expression and distribution of members of the annexin family in flowering plants, especially Arabidopsis.

  6. HSV-I and the cellular DNA damage response

    OpenAIRE

    Smith, Samantha; Weller, Sandra K.

    2015-01-01

    Peter Wildy first observed genetic recombination between strains of HSV in 1955. At the time, knowledge of DNA repair mechanisms was limited, and it has only been in the last decade that particular DNA damage response (DDR) pathways have been examined in the context of viral infections. One of the first reports addressing the interaction between a cellular DDR protein and HSV-1 was the observation by Lees-Miller et al. that DNA-dependent protein kinase catalytic subunit levels were depleted i...

  7. Cellular response within the periodontal ligament on application of orthodontic forces

    Directory of Open Access Journals (Sweden)

    Nazeer Ahmed Meeran

    2013-01-01

    Full Text Available During application of controlled orthodontic force on teeth, remodeling of the periodontal ligament (PDL and the alveolar bone takes place. Orthodontic forces induce a multifaceted bone remodeling response. Osteoclasts responsible for bone resorption are mainly derived from the macrophages and osteoblasts are produced by proliferations of the cells of the periodontal ligament. Orthodontic force produces local alterations in vascularity, as well as cellular and extracellular matrix reorganization, leading to the synthesis and release of various neurotransmitters, cytokines, growth factors, colony-stimulating factors, and metabolites of arachidonic acid. Although many studies have been reported in the orthodontic and related scientific literature, research is constantly being done in this field resulting in numerous current updates in the biology of tooth movement, in response to orthodontic force. Therefore, the aim of this review is to describe the mechanical and biological processes taking place at the cellular level during orthodontic tooth movement.

  8. 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.

  9. Scolopendin 2 leads to cellular stress response in Candida albicans.

    Science.gov (United States)

    Lee, Heejeong; Hwang, Jae-Sam; Lee, Dong Gun

    2016-07-01

    Centipedes, a kind of arthropod, have been reported to produce antimicrobial peptides as part of an innate immune response. Scolopendin 2 (AGLQFPVGRIGRLLRK) is a novel antimicrobial peptide derived from the body of the centipede Scolopendra subspinipes mutilans by using RNA sequencing. To investigate the intracellular responses induced by scolopendin 2, reactive oxygen species (ROS) and glutathione accumulation and lipid peroxidation were monitored over sublethal and lethal doses. Intracellular ROS and antioxidant molecule levels were elevated and lipids were peroxidized at sublethal concentrations. Moreover, the Ca(2+) released from the endoplasmic reticulum accumulated in the cytosol and mitochondria. These stress responses were considered to be associated with yeast apoptosis. Candida albicans cells exposed to scolopendin 2 were identified using diagnostic markers of apoptotic response. Various responses such as phosphatidylserine externalization, chromatin condensation, and nuclear fragmentation were exhibited. Scolopendin 2 disrupted the mitochondrial membrane potential and activated metacaspase, which was mediated by cytochrome c release. In conclusion, treatment of C. albicans with scolopendin 2 induced the apoptotic response at sublethal doses, which in turn led to mitochondrial dysfunction, metacaspase activation, and cell death. The cationic antimicrobial peptide scolopendin 2 from the centipede is a potential antifungal peptide, triggering the apoptotic response. PMID:27207682

  10. Cellular responses of embryonic hyaline cartilage to experimental wounding in vitro.

    Science.gov (United States)

    Walker, E A; Verner, A; Flannery, C R; Archer, C W

    2000-01-01

    It is well established that the reparative potential of many tissues is greatest during embryonic development. Despite the extensive literature documenting repair in nonembryonic cartilage models, there is no comparable wealth of experience relating to embryonic cartilage repair. With the embryonic chick sternum as a model of hyaline cartilage, this paper accounts cellular responses and alterations in extracellular matrix composition in response to experimental wounding in vitro. Creation of an experimental lesion induced a rapid (apoptosis and the expression of alpha5 and alpha6 integrin subunits. PMID:10716275

  11. Cellular mechanisms of cadmium-induced toxicity: a review.

    Science.gov (United States)

    Rani, Anju; Kumar, Anuj; Lal, Ankita; Pant, Manu

    2014-08-01

    Cadmium is a widespread toxic pollutant of occupational and environmental concern because of its diverse toxic effects: extremely protracted biological half-life (approximately 20-30 years in humans), low rate of excretion from the body and storage predominantly in soft tissues (primarily, liver and kidneys). It is an extremely toxic element of continuing concern because environmental levels have risen steadily due to continued worldwide anthropogenic mobilization. Cadmium is absorbed in significant quantities from cigarette smoke, food, water and air contamination and is known to have numerous undesirable effects in both humans and animals. Cadmium has a diversity of toxic effects including nephrotoxicity, carcinogenicity, teratogenicity and endocrine and reproductive toxicities. At the cellular level, cadmium affects cell proliferation, differentiation, apoptosis and other cellular activities. Current evidence suggests that exposure to cadmium induces genomic instability through complex and multifactorial mechanisms. Most important seems to be cadmium interaction with DNA repair mechanism, generation of reactive oxygen species and induction of apoptosis. In this article, we have reviewed recent developments and findings on cadmium toxicology. PMID:24117228

  12. Complex cellular responses to tooth wear in rodent molar.

    Science.gov (United States)

    Mahdee, A; Alhelal, A; Eastham, J; Whitworth, J; Gillespie, J I

    2016-01-01

    The arrangement and roles of the odontoblast and its process in sensing and responding to injuries such as tooth wear are incompletely understood. Evidence is presented that dentine exposure by tooth wear triggers structural and functional changes that aim to maintain tooth integrity. Mandibular first molars from freshly culled 8 week Wistar rats were prepared for light microscopy ground-sections (n=6), or fixed in 4% paraformaldehyde, decalcified in 17% EDTA, sectioned and stained with antibodies to cyto-skeletal proteins (vimentin (vim), α-tubulin (tub) and α-actin), cellular homeostatic elements (sodium potassium ATPase (NaK-ATPase) and sodium hydrogen exchanger (NHE-1)), and sensory nerve fibres (CGRP) (n=10) for fluorescence microscopy of worn and unworn regions of the mesial cusp. Immunoreactivity (IR) to vim, actin, NaK-ATPase and CGRP was confined to the pulpal third of odontoblast processes (OPs). IR to tub and nhe-1 was expressed by OPs in full dentine thickness. In areas associated with dentine exposure, the tubules contained no OPs. In regions with intact dentine, odontoblasts were arranged in a single cell layer and easily distinguished from the sub-odontoblast cells. In regions with open tubules, the odontoblasts were in stratified or pseudo-stratified in arrangement. Differences in structural antibody expression suggest a previously unreported heterogeneity of the odontoblast population and variations in different regions of the OP. This combined with differences in OPs extension and pulp cellular arrangement in worn and unworn regions suggests active and dynamic cellular responses to the opening of dentinal tubules by tooth wear. PMID:26547699

  13. Naringin abrogated radiation induced oxidative stress through modulation of redox regulated cellular signaling system

    International Nuclear Information System (INIS)

    Ionizing radiation is widely used as major diagnostic and therapeutic applications. However, the deleterious effects of ionizing radiation are due to generation of reactive oxygen species. The amounts of ionizing radiation that can be given to treat malignant tumours are often limited by toxicity in the surrounding normal tissues and organs. The aim of this study was to investigate the role of Naringin (NG), a natural flavonoid, present in many plant parts against radiation induced oxidative stress with an evidence based exploration of the mechanism involved. Isolated murine splenocyte were irradiated with γ radiation (6 Gy) along with/without different concentrations of NG (50 and 100 μM). Biochemical, immunoblot, flow cytometry and immunofluorescence study was subject to be performed to observe its molecular mechanisms of action. Pretreatment with NG significantly prevented the radiation induced intracellular ROS generation, therefore prevented cellular TBARS formation and development of cellular nitrite. NG showed the significant reduction in nuclear DNA damage with respect to irradiated splenocyte through inhibition of DNA-PKcs and p-γH2AX. It recovered radiation induced reduced cell viability through modulation of redox regulated cell signaling system. It resulted in significant inhibition of radiation induced G1/S phase cell cycle arrest mediated by modulation of p53 dependent p21/WAF1 expression followed by Cyclin E and CDK2 expression. NG was involved in blocking radiation induced p38 function; reversed radiation mediated differential stress response through inhibition of NF-κB pathway. It prevented p-IKKα/β, p-IκBα, p-p65, COX2 expression. It also reversed the radiation induced p38/NF-κB guided inflammatory development. Thus it down regulated radiation induced CRP, MCP-1, and iNOS2 gene expression. This novel role of naringin provides a basis for therapeutic applications in future against radiation induced molecular and cellular functional

  14. 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.

  15. 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

  16. Cellular responses of Prochilodus lineatus hepatocytes after cylindrospermopsin exposure.

    Science.gov (United States)

    Liebel, S; Oliveira Ribeiro, C A; Silva, R C; Ramsdorf, W A; Cestari, M M; Magalhães, V F; Garcia, J R E; Esquivel, B M; Filipak Neto, F

    2011-10-01

    Cylindrospermopsin is a potent toxicant for eukaryotic cells produced by several cyanobacteria. Recently, primary hepatocyte cultures of Neotropical fish have been established, demonstrating to be a quite efficient in vitro model for cellular toxicology studies. In the current study, a protocol for culture of Prochilodus lineatus hepatocytes was established and utilized to investigate the cellular responses to purified cylindrospermopsin exposure. Hepatocytes were successfully dissociated with dispase, resulting in a cell yield of 6.36 × 10(7)cells g(-1) of liver, viability of 97% and attachment on uncoated culture flasks. For investigation of cylindrospermopsin effects, hepatocytes were dissociated, cultured during 96 h and exposed to three concentrations of the toxin (0.1, 1.0 or 10 μgl(-1)) for 72 h. Cylindrospermopsin exposure significantly decreased cell viability (0.1 and 1 μgl(-1)) and multixenobiotic resistance mechanism, MXR (all exposed groups), but increased reactive oxygen/nitrogen species levels (all exposed groups) and lipid peroxidation (10 μgl(-1)). On the other hand no significant alterations were observed for other biochemical biomarkers as 2GSH/GSSG ratio, protein carbonyl levels and DNA strand breaks or glutathione S-transferase and glucose 6-phosphate dehydrogenase activities. In conclusion, hepatocytes might be made sensitive to cylindrospermopsin, at least in part, due to reduction of xenobiotics and endobiotics efflux capacity by MXR. Additionally, the toxin exposure suggests important issues regarding hepatocytes survival at the lowest cylindrospermopsin concentrations. PMID:21600976

  17. Modified cellular immune responses in dogs infected with Echinococcus multilocularis.

    Science.gov (United States)

    Kato, Naoko; Nonaka, Nariaki; Oku, Yuzaburo; Kamiya, Masao

    2005-03-01

    Parasite-specific antigen responses and lymphocyte blastogenesis in dogs orally inoculated with Echinococcus multilocuralis metacestodes were examined. Serum IgG1 (Th2-oriented) and IgG2 (Th 1-oriented) levels against somatic and excretory-secretory (ES) antigens of protoscoleces and adult worms increased from 7 days post-infection (DPI), with the highest responses against protoscolex excretory-secretory antigen (PES). Specific blastogenesis of peripheral blood mononuclear cells (PBMC) against the parasite antigens was not observed during the 21-day infection period, but Peyer's patches cells from one out of two dogs at 21 DPI showed blastogenesis against PES (stimulation index: 4.65). Interestingly, only at 7 DPI were concanavalin A (ConA)-induce proliferative responses of PBMC reduced. Moreover, ConA-induced proliferative responses of lymphocytes from various origins were suppressed by the addition of parasite antigens, especially with PES. These data suggest that although both Th1- and Th2-oriented humoral immune responses were observed in E. multilocularis infected dogs, the parasite antigens, especially PES, may have incompletely suppressed lymphocyte responses in these dogs. PMID:15719262

  18. Cellular response to titanium discs coated with polyelectrolyte multilayer films

    Institute of Scientific and Technical Information of China (English)

    Jing Zhan; Qiao-jie Luo; Ying Huang; Xiao-dong Li

    2014-01-01

    The purpose of this study was to investigate the effects of polyelectrolyte multilayer (PEM) coatings on the biological behavior of titanium (Ti) substrates. Collagen typeΙ/hyaluronic acid (Col/HA) and chitosan/hyaluronic acid (Chi/HA) multilayer PEM coatings were in-troduced onto Ti substrates using layer-by-layer assembly. Contact angle instruments and quartz crystal microbalance were used for film characterization. The results obtained showed that both Col/HA and Chi/HA surfaces had high hydrophilicity and promoted cell adhesion in MC3T3-E1 pre-osteoblast and human gingival fibroblast cells. In addition, the synthesis of function-related proteins and gene expression levels in both MC3T3-E1 and fibroblast cells was higher for the Col/HA coating compared with the Chi/HA coating, indicating better cellu-lar response to the Col/HA coating.

  19. 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.

  20. Role of natural antioxidant mediated cellular radiation response

    International Nuclear Information System (INIS)

    Need for the development of radioprotector was felt after witnessing the disastrous effects of ionizing radiation since World War II. Ionizing radiation is fatal for all living beings. Formation of free radicals (reactive oxygen species) are believed to be the prime reason for various cellular and molecular damages and death of cells. Different chemical agents having ability to quench these free radicals were selected logically for the development of radiation counter measure agents. WR2712 is the first FDA approved clinical cytoprotector, however acute toxicity necessitated search of safe chemical radiation countermeasure agents. Natural antioxidants possess strong antiradical properties and relatively less toxic and therefore currently persuaded for development of radioprotector. The objectives were to undertake a comprehensive mechanism based selection of suitable natural antioxidant compounds and evaluate their antiradical properties using standard assays. Further, validation of the radioprotective efficacy of selected antioxidant in vitro models and investigation in cell lines for elucidation of mechanism underlying radioprotection. Results of modified antiradical assays (ABTS, DPPH, ORAC and FRAP) suggested strong potential of sesamol in comparison to fifteen different antioxidants. Further comparative in vitro studies, prior treatment of antioxidant showed strong potential of sesamol with dose modifying factors of 10 (plasmid DNA) and 3 (V79 cells). The corresponding dose modifying factor of melatonin was 5 and 1.3 respectively. Furthermore, sesamol decreased radiation induced apoptosis, chromosomal aberration, cell cycle arrest, oxidative damages, mitochondrial depolarization in HEK293 cells. The mechanism of radioprotection proposed to be due to enhanced antioxidant enzyme activity and balance in cellular redox together with scavenging of free radicals by sesamol. Due to these potential of sesamol, further evaluation in preclinical models are required for

  1. 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.

  2. 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.

  3. PTTG1 attenuates drug-induced cellular senescence.

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    Yunguang Tong

    Full Text Available As PTTG1 (pituitary tumor transforming gene abundance correlates with adverse outcomes in cancer treatment, we determined mechanisms underlying this observation by assessing the role of PTTG1 in regulating cell response to anti-neoplastic drugs. HCT116 cells devoid of PTTG1 (PTTG1(-/- exhibited enhanced drug sensitivity as assessed by measuring BrdU incorporation in vitro. Apoptosis, mitosis catastrophe or DNA damage were not detected, but features of senescence were observed using low doses of doxorubicin and TSA. The number of drug-induced PTTG1(-/- senescent cells increased ∼4 fold as compared to WT PTTG1-replete cells (p<0.001. p21, an important regulator of cell senescence, was induced ∼3 fold in HCT116 PTTG1(-/- cells upon doxorubicin or Trichostatin A treatment. Binding of Sp1, p53 and p300 to the p21 promoter was enhanced in PTTG1(-/- cells after treatment, suggesting transcriptional regulation of p21. p21 knock down abrogated the observed senescent effects of these drugs, indicating that PTTG1 likely suppresses p21 to regulate drug-induced senescence. PTTG1 also regulated SW620 colon cancer cells response to doxorubicin and TSA mediated by p21. Subcutaneously xenografted PTTG1(-/- HCT116 cells developed smaller tumors and exhibited enhanced responses to doxorubicin. PTTG1(-/- tumor tissue derived from excised tumors exhibited increased doxorubicin-induced senescence. As senescence is a determinant of cell responses to anti-neoplastic treatments, these findings suggest PTTG1 as a tumor cell marker to predict anti-neoplastic treatment outcomes.

  4. Cocaine-induced adaptations in cellular redox balance contributes to enduring behavioral plasticity.

    Science.gov (United States)

    Uys, Joachim D; Knackstedt, Lori; Hurt, Phelipe; Tew, Kenneth D; Manevich, Yefim; Hutchens, Steven; Townsend, Danyelle M; Kalivas, Peter W

    2011-11-01

    Impaired glutamate homeostasis in the nucleus accumbens has been linked to cocaine relapse in animal models, and results in part from cocaine-induced downregulation of the cystine-glutamate exchanger. In addition to regulating extracellular glutamate, the uptake of cystine by the exchanger is a rate-limiting step in the synthesis of glutathione (GSH). GSH is critical for balancing cellular redox in response to oxidative stress. Cocaine administration induces oxidative stress, and we first determined if downregulated cystine-glutamate exchange alters redox homeostasis in rats withdrawn from daily cocaine injections and then challenged with acute cocaine. Among the daily cocaine-induced changes in redox homeostasis were an increase in protein S-glutathionylation and a decrease in expression of GSH-S-transferase pi (GSTpi). To mimic reduced GSTpi, a genetic mouse model of GSTpi deletion or pharmacological inhibition of GSTpi by administering ketoprofen during daily cocaine administration was used. The capacity of cocaine to induce conditioned place preference or locomotor sensitization was augmented, indicating that reducing GSTpi may contribute to cocaine-induced behavioral neuroplasticity. Conversely, an acute cocaine challenge after withdrawal from daily cocaine elicited a marked increase in accumbens GSTpi, and the expression of behavioral sensitization to a cocaine challenge injection was inhibited by ketoprofen pretreatment; supporting a protective effect by the acute cocaine-induced rise in GSTpi. Together, these data indicate that cocaine-induced oxidative stress induces changes in GSTpi that contribute to cocaine-induced behavioral plasticity. PMID:21796101

  5. 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.

  6. Relationship between cellular response models and biochemical mechanisms

    International Nuclear Information System (INIS)

    In most cellular response experiments, survival reflects the kinetics of a variety of damage and repair processes. Unfortunately, biochemical studies of molecular repair deal with mechanisms which cannot be readily correlated with these kinetic observations. The difference in these approaches sometimes leads to confusion over terms such as potentially-lethal and sublethal damage. These terms were introduced with operation definitions, derived from kinetic studies of cell survival, but some researchers have since attempted to associate them with specific biochemical mechanisms. Consequently, the terms are often used in totally different ways be different investigators. The use of carefully constructed models originating either out of assumptions based on mechanisms, or on kinetics, can be used to design experiments to eliminate some alternative kinetic schemes. In turn, some mechanisms may also be eliminated, resulting in a reduction in the number of mechanisms which must be investigated biochemically. One must take advantage of a wide range of specialized radiation procedures in order to accomplish this. Examples of the use of such specialized experimental designs, which have led to a more detailed understanding of the kinetics of both algal and mammalian cell responses, are discussed

  7. The surgically induced stress response.

    Science.gov (United States)

    Finnerty, Celeste C; Mabvuure, Nigel Tapiwa; Ali, Arham; Kozar, Rosemary A; Herndon, David N

    2013-09-01

    The stress response to surgery, critical illness, trauma, and burns encompasses derangements of metabolic and physiological processes that induce perturbations in the inflammatory, acute phase, hormonal, and genomic responses. Hypermetabolism and hypercatabolism result, leading to muscle wasting, impaired immune function and wound healing, organ failure, and death. The surgery-induced stress response is largely similar to that triggered by traumatic injuries; the duration of the stress response, however, varies according to the severity of injury (surgical or traumatic). This spectrum of injuries and insults ranges from small lacerations to severe insults such as large poly-traumatic and burn injuries. Burn injuries provide an extreme model of trauma induced stress responses that can be used to study the long-term effects of a prolonged stress response. Although the stress response to acute trauma evolved to confer improved chances of survival following injury, in modern surgical practice the stress response can be detrimental. PMID:24009246

  8. Curcumin enhances recovery of pancreatic islets from cellular stress induced inflammation and apoptosis in diabetic rats

    Energy Technology Data Exchange (ETDEWEB)

    Rashid, Kahkashan; Sil, Parames C., E-mail: parames@jcbose.ac.in

    2015-02-01

    The phytochemical, curcumin, has been reported to play many beneficial roles. However, under diabetic conditions, the detail mechanism of its beneficial action in the glucose homeostasis regulatory organ, pancreas, is poorly understood. The present study has been designed and carried out to explore the role of curcumin in the pancreatic tissue of STZ induced and cellular stress mediated diabetes in eight weeks old male Wistar rats. Diabetes was induced with a single intraperitoneal dose of STZ (65 mg/kg body weight). Post to diabetes induction, animals were treated with curcumin at a dose of 100 mg/kg body weight for eight weeks. Underlying molecular and cellular mechanism was determined using various biochemical assays, DNA fragmentation, FACS, histology, immunoblotting and ELISA. Treatment with curcumin reduced blood glucose level, increased plasma insulin and mitigated oxidative stress related markers. In vivo and in vitro experimental results revealed increased levels of proinflammatory cytokines (TNF-α, IL1-β and IFN-γ), reduced level of cellular defense proteins (Nrf-2 and HO-1) and glucose transporter (GLUT-2) along with enhanced levels of signaling molecules of ER stress dependent and independent apoptosis (cleaved Caspase-12/9/8/3) in STZ administered group. Treatment with curcumin ameliorated all the adverse changes and helps the organ back to its normal physiology. Results suggest that curcumin protects pancreatic beta-cells by attenuating inflammatory responses, and inhibiting ER/mitochondrial dependent and independent pathways of apoptosis and crosstalk between them. This uniqueness and absence of any detectable adverse effect proposes the possibility of using this molecule as an effective protector in the cellular stress mediated diabetes mellitus. - Highlights: • STZ induced cellular stress plays a vital role in pancreatic dysfunction. • Cellular stress causes inflammation, pancreatic islet cell death and diabetes. • Deregulation of Nrf-2

  9. Curcumin enhances recovery of pancreatic islets from cellular stress induced inflammation and apoptosis in diabetic rats

    International Nuclear Information System (INIS)

    The phytochemical, curcumin, has been reported to play many beneficial roles. However, under diabetic conditions, the detail mechanism of its beneficial action in the glucose homeostasis regulatory organ, pancreas, is poorly understood. The present study has been designed and carried out to explore the role of curcumin in the pancreatic tissue of STZ induced and cellular stress mediated diabetes in eight weeks old male Wistar rats. Diabetes was induced with a single intraperitoneal dose of STZ (65 mg/kg body weight). Post to diabetes induction, animals were treated with curcumin at a dose of 100 mg/kg body weight for eight weeks. Underlying molecular and cellular mechanism was determined using various biochemical assays, DNA fragmentation, FACS, histology, immunoblotting and ELISA. Treatment with curcumin reduced blood glucose level, increased plasma insulin and mitigated oxidative stress related markers. In vivo and in vitro experimental results revealed increased levels of proinflammatory cytokines (TNF-α, IL1-β and IFN-γ), reduced level of cellular defense proteins (Nrf-2 and HO-1) and glucose transporter (GLUT-2) along with enhanced levels of signaling molecules of ER stress dependent and independent apoptosis (cleaved Caspase-12/9/8/3) in STZ administered group. Treatment with curcumin ameliorated all the adverse changes and helps the organ back to its normal physiology. Results suggest that curcumin protects pancreatic beta-cells by attenuating inflammatory responses, and inhibiting ER/mitochondrial dependent and independent pathways of apoptosis and crosstalk between them. This uniqueness and absence of any detectable adverse effect proposes the possibility of using this molecule as an effective protector in the cellular stress mediated diabetes mellitus. - Highlights: • STZ induced cellular stress plays a vital role in pancreatic dysfunction. • Cellular stress causes inflammation, pancreatic islet cell death and diabetes. • Deregulation of Nrf-2

  10. The Surgically Induced Stress Response

    OpenAIRE

    Finnerty, Celeste C.; Mabvuure, Nigel Tapiwa; Ali, Arham; Kozar, Rosemary A.; Herndon, David N

    2013-01-01

    The stress response to surgery, critical illness, trauma, and burns encompasses derangements of metabolic and physiological processes which induce perturbations in the inflammatory, acute phase, hormonal, and genomic responses. Hypermetabolism and hypercatabolism result, leading to muscle wasting, impaired immune function and wound healing, organ failure, and death. The surgery-induced stress response is largely similar to that triggered by traumatic injuries; the duration of the stress respo...

  11. Neu1 sialidase and matrix metalloproteinase-9 cross-talk regulates nucleic acid-induced endosomal TOLL-like receptor-7 and -9 activation, cellular signaling and pro-inflammatory responses.

    Science.gov (United States)

    Abdulkhalek, Samar; Szewczuk, Myron R

    2013-11-01

    The precise mechanism(s) by which intracellular TOLL-like receptors (TLRs) become activated by their ligands remains unclear. Here, we report a molecular organizational G-protein coupled receptor (GPCR) signaling platform to potentiate a novel mammalian neuraminidase-1 (Neu1) and matrix metalloproteinase-9 (MMP-9) cross-talk in alliance with neuromedin B GPCR, all of which form a tripartite complex with TLR-7 and -9. siRNA silencing Neu1, MMP-9 and neuromedin-B GPCR in RAW-blue macrophage cells significantly reduced TLR7 imiquimod- and TLR9 ODN1826-induced NF-κB (NF-κB-pSer(536)) activity. Tamiflu, specific MMP-9 inhibitor, neuromedin B receptor specific antagonist BIM23127, and the selective inhibitor of whole heterotrimeric G-protein complex BIM-46174 significantly block nucleic acid-induced TLR-7 and -9 MyD88 recruitment, NF-κB activation and proinflammatory TNFα and MCP-1 cytokine responses. For the first time, Neu1 clearly plays a central role in mediating nucleic acid-induced intracellular TLR activation, and the interactions involving NMBR-MMP9-Neu1 cross-talk constitute a novel intracellular TLR signaling platform that is essential for NF-κB activation and pro-inflammatory responses. PMID:23827939

  12. 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

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

    International Nuclear Information System (INIS)

    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

  14. Antioxidant Activity of Lawsonia inermis Extracts Inhibits Chromium(VI-Induced Cellular and DNA Toxicity

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    Gunjan Guha

    2011-01-01

    Full Text Available Hexavalent chromium Cr(VI is a very strong oxidant which consequently causes high cytotoxicity through oxidative stress. Prevention of Cr(VI-induced cellular damage has been sought in this study in aqueous and methanolic extracts of Lawsonia inermis Linn. (Lythraceae, commonly known as Henna. The extracts showed significant (P < .05 potential in scavenging free radicals (DPPH• and ABTS•+ and Fe3+, and in inhibiting lipid peroxidation. DNA damage caused by exposure of pBR322 to Cr(VI-UV is markedly inhibited by both extracts in varying degrees. A distinct decline in Cr(VI-induced cytotoxicity was noticed in MDA-MB-435S (human breast carcinoma cells with an increase in dosage of both extracts individually. Furthermore, both extracts proved to contain a high content of phenolic compounds which were found to have a strong and significant (P < .05 positive correlation to the radical scavenging potential, lipid peroxidation inhibition capacity and cyto-protective efficiency against Cr(VI-induced oxidative cellular damage. HPLC analysis identified some of the major phenolic compounds in both extracts, which might be responsible for the antioxidant potential and the properties of DNA and cyto-protection. This study contributes to the search for natural resources that might yield potent therapeutic drugs against Cr(VI-induced oxidative cell damage.

  15. Calculation of impulse responses with a cellular automata algorithm

    Science.gov (United States)

    Barjau, Ana

    2001-05-01

    The air columns in musical instruments usually have a predominant dimension and thus are very often modeled as 1D systems where uniparametric waves propagate. Different algorithms can be found in the literature to simulate this propagation. The more widely used are finite difference schemes and delay lines. A finite difference scheme (FD) is a numerical integration of a differential formulation (the wave equation), while delay lines (DL) use analytical exact solutions of the wave equation over finite lengths. A new and different approach is that of a cellular automaton (CA) scheme. The underlying philosophy is opposite those of FD and DL, as the starting point is not the wave equation. In a CA approach, the phenomenon to be studied is reduced to a few simple physical laws that are applied to a set of cells representing the physical system (in the present case, the propagation medium). In this paper, a CA will be proposed to obtain the impulse response of different bore geometries. The results will be compared to those obtained with other algorithms.

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

    Science.gov (United States)

    Luna-Olivares, Luz Adilia; Kyvsgaard, Niels Chr; Ferdushy, Tania; Nejsum, Peter; Thamsborg, Stig Milan; Roepstorff, Allan; Iburg, Tine Moesgaard

    2015-07-01

    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 as uninfected controls. Six infected and four control chickens were necropsied at each time point 3, 7, 10, 14, 21, 28 and 42 days post-infection (dpi). Samples for histopathology were taken from three sites of the jejunoileum. Significantly higher eosinophil counts were seen in infected chickens compared to uninfected at 3, 7, 10, 14 and 28 dpi (P galli infection induced changes in the mucosal thickness as reduced villi length at 7, 10, 14, 21 and 28 dpi and in the degree of general cellular infiltration in the lamina propria of the mucosal layer. No adult worms were seen during the experiment; therefore, A. galli larvae have elicited a moderate cellular response in the lamina propria, mainly consisting of eosinophils in the early phase and later of mast cells. PMID:25877388

  17. JC virus induces altered patterns of cellular gene expression: Interferon-inducible genes as major transcriptional targets

    International Nuclear Information System (INIS)

    Human polyomavirus JC (JCV) infects 80% of the population worldwide. Primary infection, typically occurring during childhood, is asymptomatic in immunocompetent individuals and results in lifelong latency and persistent infection. However, among the severely immunocompromised, JCV may cause a fatal demyelinating disease, progressive multifocal leukoencephalopathy (PML). Virus-host interactions influencing persistence and pathogenicity are not well understood, although significant regulation of JCV activity is thought to occur at the level of transcription. Regulation of the JCV early and late promoters during the lytic cycle is a complex event that requires participation of both viral and cellular factors. We have used cDNA microarray technology to analyze global alterations in gene expression in JCV-permissive primary human fetal glial cells (PHFG). Expression of more than 400 cellular genes was altered, including many that influence cell proliferation, cell communication and interferon (IFN)-mediated host defense responses. Genes in the latter category included signal transducer and activator of transcription 1 (STAT1), interferon stimulating gene 56 (ISG56), myxovirus resistance 1 (MxA), 2'5'-oligoadenylate synthetase (OAS), and cig5. The expression of these genes was further confirmed in JCV-infected PHFG cells and the human glioblastoma cell line U87MG to ensure the specificity of JCV in inducing this strong antiviral response. Results obtained by real-time RT-PCR and Western blot analyses supported the microarray data and provide temporal information related to virus-induced changes in the IFN response pathway. Our data indicate that the induction of an antiviral response may be one of the cellular factors regulating/controlling JCV replication in immunocompetent hosts and therefore constraining the development of PML

  18. MF59- and Al(OH3-adjuvanted Staphylococcus aureus (4C-Staph vaccines induce sustained protective humoral and cellular immune responses, with a critical role for effector CD4 T cells at low antibody titers.

    Directory of Open Access Journals (Sweden)

    Elisabetta eMonaci

    2015-09-01

    Full Text Available Staphylococcus aureus (S. aureus is an important opportunistic pathogen that may cause invasive life-threatening infections like sepsis and pneumonia. Due to increasing antibiotic-resistance, the development of an effective vaccine against S. aureus is needed. Although a correlate of protection against staphylococcal diseases is not yet established, several findings suggest that both antibodies and CD4 T cells might contribute to optimal immunity. In this study, we show that adjuvanting a multivalent vaccine (4C-Staph with MF59, an oil-in-water emulsion licensed in human vaccines, further potentiated antigen-specific IgG titers and CD4 T cell responses compared to alum and conferred protection in the peritonitis model of S. aureus infection. Moreover, we showed that MF59- and alum-adjuvanted 4C-Staph vaccines induced persistent antigen-specific humoral and T cell responses, and protected mice from infection up to 4 months after immunization. Furthermore, 4C-Staph formulated with MF59 was used to investigate which immune compartment is involved in vaccine-induced protection. Using CD4 T cell-depleted mice or B cell deficient mice, we demonstrated that both T and B cell responses contributed to 4C-Staph vaccine-mediated protective immunity. However, the role of CD4 T cells seemed more evident in the presence of low antibody responses. This study provides preclinical data further supporting the use of the adjuvanted 4C-Staph vaccines against S. aureus diseases, and provides critical insights on the correlates of protective immunity necessary to combat this pathogen.

  19. PI3K/AKT and ERK regulate retinoic acid-induced neuroblastoma cellular differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, Jingbo [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Paul, Pritha; Lee, Sora [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Qiao, Lan; Josifi, Erlena; Tiao, Joshua R. [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Chung, Dai H., E-mail: dai.chung@vanderbilt.edu [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN 37232 (United States)

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer Retinoic acid (RA) induces neuroblastoma cells differentiation, which is accompanied by G0/G1 cell cycle arrest. Black-Right-Pointing-Pointer RA resulted in neuroblastoma cell survival and inhibition of DNA fragmentation; this is regulated by PI3K pathway. Black-Right-Pointing-Pointer RA activates PI3K and ERK1/2 pathway; PI3K pathway mediates RA-induced neuroblastoma cell differentiation. Black-Right-Pointing-Pointer Upregulation of p21 is necessary for RA-induced neuroblastoma cell differentiation. -- Abstract: Neuroblastoma, the most common extra-cranial solid tumor in infants and children, is characterized by a high rate of spontaneous remissions in infancy. Retinoic acid (RA) has been known to induce neuroblastoma differentiation; however, the molecular mechanisms and signaling pathways that are responsible for RA-mediated neuroblastoma cell differentiation remain unclear. Here, we sought to determine the cell signaling processes involved in RA-induced cellular differentiation. Upon RA administration, human neuroblastoma cell lines, SK-N-SH and BE(2)-C, demonstrated neurite extensions, which is an indicator of neuronal cell differentiation. Moreover, cell cycle arrest occurred in G1/G0 phase. The protein levels of cyclin-dependent kinase inhibitors, p21 and p27{sup Kip}, which inhibit cell proliferation by blocking cell cycle progression at G1/S phase, increased after RA treatment. Interestingly, RA promoted cell survival during the differentiation process, hence suggesting a potential mechanism for neuroblastoma resistance to RA therapy. Importantly, we found that the PI3K/AKT pathway is required for RA-induced neuroblastoma cell differentiation. Our results elucidated the molecular mechanism of RA-induced neuroblastoma cellular differentiation, which may be important for developing novel therapeutic strategy against poorly differentiated neuroblastoma.

  20. Cellular and humoral responses to Leishmania major virulence factors in healed cutaneous leishmaniasis and Mediterranean visceral leishmaniasis patients.

    OpenAIRE

    Lakhal-Naouar, Inès; Boussoffara, Thouraya; Meddeb-Garnaoui, Amel; Ben Achour-Chenik, Yosser; Louzir, Hechmi; Chenik, Mehdi

    2009-01-01

    Cellular and humoral immune responses of healed cutaneous leishmaniasis and Mediterranean visceral leishmaniasis patients were evaluated against results for Leishmania major virulence proteins L. major protein disulfide isomerase (LmPDI) and mitogen-activated protein kinase kinase (MAPKK). Only MAPKK induces significant peripheral blood mononuclear cell proliferation with gamma interferon production as well as antibody responses. Thus, MAPKK may be of interest in Leishmania vaccination and se...

  1. Molecular events basic to cellular radiation response. Progress report

    International Nuclear Information System (INIS)

    Work during the past year has been focused on three areas related to the cellular effects of radiation. Radiation effects on RNA and the regulation of gene expression and amino acid-nucleic acid interactions were studied. Studies on the radiation response of RNA in growing and confluent cells were continued. We have derived radiation survival curves and demonstrated repair of potentially lethal damage in 3T3 cells. Studies of giant cell formation and turnover of ribosomal RNA in irradiated cells has demonstrated differences in growing and confluent cells. We have sought evidence consistent with our hypothesis for regulation of eukaryotic gene expression with segments of RNA reutilized to prime new RNA synthesis. Data derived from the turnover of ribosomal RNA and the methylation pattern of ribosomal RNA during turnover are consistent with the possibility that a segment of 18s ribosomal RNA is being conserved during new RNA synthesis. We were unable to show reutilization of the 5' trinucleotide of 18s and 28s ribosomal RNA but did find a ribonuclease resistant oligonucleotide in 18s RNA which appeared to be reutilized. In studies of amino acid nucleic-acid interactions using nuclear magnetic resonance spectroscopy we have been able to successfully synthesize an amidate and begin an examination of the intramolecular interactions. We have also studied intermolecular interactions betweentryptophan and nucleoside monophosphates and found upfield shifts which provide evidence for preferential stacking of the 6-membered ring of tryptophan with adenine and evidence for specific geometry of interactions of tryptophan with cytosine. (U.S.)

  2. Studies on cellular immunity in patients with renal carcinoma: radiation-induced inhibition of leukocyte migration

    International Nuclear Information System (INIS)

    Thirty-two patients with hypernephroma (renal carcinoma) untreated or preoperatively exposed to local radiotherapy, were examined for tumor-directed cellular hypersensitivity by means of the indirect leukocyte migration test (LMT). (a) When soluble tumor extracts from preoperatively radiated hypernephromas were tested with autologous lymphocytes, 17 of 19 cancer patients gave a positive response; 10 of 11 were positive with allogenic lymphocytes from hypernephroma patients. In no instance could migration inhibition be induced with allogenic lymphocytes from 14 normal donors. Similarly, in 9 of 10 patients there was no significant inhibition with allogenic lymphocytes from patients with histologically different types of malignant tumors other than hypernephroma. (b) Tissue extracts from untreated hypernephromas failed to react in 12 of 13 patients when treated with autologous lymphocytes. LMT's, however, became positive in 6 of 7 patients from this group by in vitro-radiation of tumor samples (60Co or electrons) before preparation of tissue extracts. This radiation-induced effect was dose-related and specific, since radiation of normal kidney tissue did not significantly influence the migratory activity of leukocytes. Our data indicating that an in vivo as well as in vitro- radiation of the hypernephroma will be suitable for the induction and the demonstration of a directed cellular immune response, may be considered as an additional perspective in the integration of radiotherapy in the management of this neoplasm. (author)

  3. 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.

  4. Interferon-γ: biological function and application for study of cellular immune response

    Directory of Open Access Journals (Sweden)

    A. A. Lutckii

    2015-01-01

    Full Text Available Cellular immune response plays a central role in control of intracellular pathogens like viruses, some bacteria and parasites. Evaluation of presence, specificity and strength of cellular immune response can be done by investigation of reaction of immune cells to specific stimulus, like antigen. The major cellular reactions to antigen stimulation are production of cytokines, proliferation and cytotoxicity. This review is focused on interferon-gamma as one of the central Th1 cytokines: its biology, immunological role and application as marker of cellular immune response.

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

    Directory of Open Access Journals (Sweden)

    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.

  6. The Surgically Induced Stress Response

    Science.gov (United States)

    Finnerty, Celeste C.; Mabvuure, Nigel Tapiwa; Ali, Arham; Kozar, Rosemary A.; Herndon, David N.

    2013-01-01

    The stress response to surgery, critical illness, trauma, and burns encompasses derangements of metabolic and physiological processes which induce perturbations in the inflammatory, acute phase, hormonal, and genomic responses. Hypermetabolism and hypercatabolism result, leading to muscle wasting, impaired immune function and wound healing, organ failure, and death. The surgery-induced stress response is largely similar to that triggered by traumatic injuries; the duration of the stress response, however, varies according to the severity of injury (surgical or traumatic). This spectrum of injuries and insults ranges from small lacerations to severe insults such as large poly-traumatic and burn injuries. Although the stress response to acute trauma evolved to improve chances of survival following injury, in modern surgical practice the stress response can be detrimental. PMID:24009246

  7. Both Complexity and Location of DNA Damage Contribute to Cellular Senescence Induced by Ionizing Radiation

    OpenAIRE

    Xurui Zhang; Caiyong Ye; Fang Sun; Wenjun Wei; Burong Hu; Jufang Wang

    2016-01-01

    Persistent DNA damage is considered as a main cause of cellular senescence induced by ionizing radiation. However, the molecular bases of the DNA damage and their contribution to cellular senescence are not completely clear. In this study, we found that both heavy ions and X-rays induced senescence in human uveal melanoma 92-1 cells. By measuring senescence associated-β-galactosidase and cell proliferation, we identified that heavy ions were more effective at inducing senescence than X-rays. ...

  8. 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

  9. Cellular membrane accommodation of copper-induced oxidative conditions in the coral Seriatopora caliendrum

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Chuan-Ho, E-mail: chtang@nmmba.gov.tw [Institute of Marine Biodiversity and Evolutionary Biology, National Dong Hwa University, Pingtung, Taiwan, ROC (China); National Museum of Marine Biology and Aquarium, Pingtung, Taiwan, ROC (China); Lin, Ching-Yu [Institute of Environmental Health, National Taiwan University, Taipei City, Taiwan, ROC (China); Lee, Shu-Hui [Center of General Education, National Kaohsiung Marine University, Kaohsiung, Taiwan, ROC (China); Wang, Wei-Hsien [National Museum of Marine Biology and Aquarium, Pingtung, Taiwan, ROC (China); Department of Marine Biotechnology and Resources and Asia-Pacific Ocean Research Center, National Sun Yat-sen University, Kaohsiung, Taiwan, ROC (China)

    2014-03-01

    Highlights: • Coral cells alter membrane lipid to accommodate copper-induce oxidative conditions • Coral membrane repair occur due to lipid alterations • Zooxanthellae release results from membrane repair by symbiosome fusion • Copper-induced lipid alterations perturb membrane-related functions in coral cells • Copper chronic effect on coral fitness are related to long-term membrane perturbation - Abstract: Oxidative stress has been associated with copper-induced toxicity in scleractinian corals. To gain insight into the accommodation of the cellular membrane to oxidative conditions, a pocilloporid coral, Seriatopora caliendrum, was exposed to copper at distinct, environmentally relevant dose for various lengths of time. Glycerophosphocholine profiling of the response of the coral to copper exposure was characterized using a validated method. The results indicate that coral lipid metabolism is programmed to induce membrane alterations in response to the cellular deterioration that occurs during the copper exposure period. Decreasing lyso-phosphatidylcholines and exchanging polyunsaturated phosphatidylcholines for polyunsaturated plasmanylcholines were the initial actions taken to prevent membrane permeabilization. To relax/resist the resulting membrane strain caused by cell/organelle swelling, the coral cells inversely exchanged polyunsaturated plasmanylcholines for polyunsaturated phosphatidylcholines and further increased the levels of monounsaturated glycerophosphocholines. At the same time, the levels of saturated phosphatidylcholines were also increased to increase membrane rigidity and protect against oxidative attack. Interestingly, such alterations in lipid metabolism were also required for membrane fusion to repair the deteriorated membranes by repopulating them with proximal lipid reservoirs, similar to symbiosome membranes. Additionally, increasing saturated and monounsaturated plasmanylcholines and inhibiting the suppression of saturated lyso

  10. 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.

  11. Cellular responses to low dose heavy-ion exposure in human cell

    Energy Technology Data Exchange (ETDEWEB)

    Morimoto, S.; Goto, S.; Kato, T.; Izumi, M.; Komiyama-Kobayashi, M.; Fukunishi, N.; Honma, M.; Hanaoka, F.; Yatagai, F

    2002-07-01

    The human lymphoblastoid cell line TK6 was used to study the cellular responses after low-dose (100, 200, 500 mGy) or high-dose (3 Gy) of X rays, C (22 keV.{mu}m{sup -1}) and Fe (1000 keV.{mu}m{sup -1}) ion exposures, p53 protein induction in individual cells was determined by indirect immunofluorescence staining. Cell-cycle progression after heavy-ion exposure was determined by using a laser scanning cytometer. A characteristic pattern of cell-cycle progression was observed with 3 Gy exposure of Fe ions but not with 100 mGy. Similarly such a pattern with 100 mGy C ion exposure did not match that with 3 Gy. The proportion of p53-induced cells is proportional to the probability of cell being hit by a primary heavy ion. The observed low-dose effect can be reflected in the probability of a hit, although detailed nature about their energy deposition must be considered for more precise estimation of such an effect. New detection methodology must be developed for identification of heavy-ion specific cellular responses. (author)

  12. Cellular responses to low dose heavy-ion exposure in human cell

    International Nuclear Information System (INIS)

    The human lymphoblastoid cell line TK6 was used to study the cellular responses after low-dose (100, 200, 500 mGy) or high-dose (3 Gy) of X rays, C (22 keV.μm-1) and Fe (1000 keV.μm-1) ion exposures, p53 protein induction in individual cells was determined by indirect immunofluorescence staining. Cell-cycle progression after heavy-ion exposure was determined by using a laser scanning cytometer. A characteristic pattern of cell-cycle progression was observed with 3 Gy exposure of Fe ions but not with 100 mGy. Similarly such a pattern with 100 mGy C ion exposure did not match that with 3 Gy. The proportion of p53-induced cells is proportional to the probability of cell being hit by a primary heavy ion. The observed low-dose effect can be reflected in the probability of a hit, although detailed nature about their energy deposition must be considered for more precise estimation of such an effect. New detection methodology must be developed for identification of heavy-ion specific cellular responses. (author)

  13. Aldolase B knockdown prevents high glucose-induced methylglyoxal overproduction and cellular dysfunction in endothelial cells.

    Directory of Open Access Journals (Sweden)

    Jianghai Liu

    Full Text Available We used cultured endothelial cells as a model to examine whether up-regulation of aldolase B and enhanced methylglyoxal (MG formation play an important role in high glucose-induced overproduction of advanced glycosylation endproducts (AGEs, oxidative stress and cellular dysfunction. High glucose (25 mM incubation up-regulated mRNA levels of aldose reductase (an enzyme converting glucose to fructose and aldolase B (a key enzyme that catalyzes MG formation from fructose and enhanced MG formation in human umbilical vein endothelial cells (HUVECs and HUVEC-derived EA. hy926 cells. High glucose-increased MG production in EA. hy926 cells was completely prevented by siRNA knockdown of aldolase B, but unaffected by siRNA knockdown of aldolase A, an enzyme responsible for MG formation during glycolysis. In addition, inhibition of cytochrome P450 2E1 or semicarbazide-sensitive amine oxidase which produces MG during the metabolism of lipid and proteins, respectively, did not alter MG production. Both high glucose (25 mM and MG (30, 100 µM increased the formation of N(ε-carboxyethyl-lysine (CEL, a MG-induced AGE, oxidative stress (determined by the generation of oxidized DCF, H(2O(2, protein carbonyls and 8-oxo-dG, O-GlcNAc modification (product of the hexosamine pathway, membrane protein kinase C activity and nuclear translocation of NF-κB in EA. hy926 cells. However, the above metabolic and signaling alterations induced by high glucose were completely prevented by knockdown of aldolase B and partially by application of aminoguanidine (a MG scavenger or alagebrium (an AGEs breaker. In conclusion, efficient inhibition of aldolase B can prevent high glucose-induced overproduction of MG and related cellular dysfunction in endothelial cells.

  14. Cellular response after irradiation: Cell cycle control and apoptosis

    International Nuclear Information System (INIS)

    The importance of apoptotic death was assessed in a set of experiments, involving eight human tumour cell lines (breast cancer, bladder carcinoma, medulloblastoma). Various aspects of the quantitative study of apoptosis and methods based on the detection of DNA fragmentation (in situ tailing and comet assay) are described and discussed. Data obtained support the hypothesis that apoptosis is not crucial for cellular radiosensitivity and that the relationship between p53 functionality or clonogenic survival and apoptosis may bee cell type specific. (author)

  15. Cellular and deafness mechanisms underlying connexin mutation induced hearing loss – A common hereditary deafness

    Directory of Open Access Journals (Sweden)

    Hong-Bo Zhao

    2015-05-01

    Full Text Available Hearing loss due to mutations in the connexin gene family which encodes gap junctional proteins is a common form of hereditary deafness. In particular, connexin 26 (Cx26, GJB2 mutations are responsible for ~50% of nonsyndromic hearing loss, which is the highest incidence of genetic disease. In the clinic, Cx26 mutations cause various auditory phenotypes ranging from profound congenital deafness at birth to mild, progressive hearing loss in late childhood. Recent experiments demonstrate that congenital deafness mainly results from cochlear developmental disorders rather than hair cell degeneration and endocochlear potential (EP reduction, while late-onset hearing loss results from reduction of active cochlear amplification, even though cochlear hair cells have no connexin expression. Moreover, new experiments further demonstrate that the hypothesized K+-recycling disruption is not a principal deafness mechanism for connexin deficiency induced hearing loss. Additionally, there is no clear relationship between specific changes in connexin (channel functions and the phenotypes of mutation-induced hearing loss. Cx30, Cx29, Cx31, and Cx43 mutations can also cause hearing loss with distinct pathological changes in the cochlea. These new studies provide invaluable information about deafness mechanisms underlying connexin mutation induced hearing loss and also provide important information for developing new protective and therapeutic strategies for this common deafness. However, the detailed cellular mechanisms underlying these pathological changes and pathogeneses of specific-mutation induced hearing loss remain unclear. Finally, little information is available for humans. Further studies to address these deficiencies are urgently required.

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

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    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.

  17. 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.

  18. 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.

  19. 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

  20. A celiac cellular phenotype, with altered LPP sub-cellular distribution, is inducible in controls by the toxic gliadin peptide P31-43.

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    Merlin Nanayakkara

    Full Text Available Celiac disease (CD is a frequent inflammatory intestinal disease, with a genetic background, caused by gliadin-containing food. Undigested gliadin peptides P31-43 and P57-68 induce innate and adaptive T cell-mediated immune responses, respectively. Alterations in the cell shape and actin cytoskeleton are present in celiac enterocytes, and gliadin peptides induce actin rearrangements in both the CD mucosa and cell lines. Cell shape is maintained by the actin cytoskeleton and focal adhesions, sites of membrane attachment to the extracellular matrix. The locus of the human Lipoma Preferred Partner (LPP gene was identified as strongly associated with CD using genome-wide association studies (GWAS. The LPP protein plays an important role in focal adhesion architecture and acts as a transcription factor in the nucleus. In this study, we examined the hypothesis that a constitutive alteration of the cell shape and the cytoskeleton, involving LPP, occurs in a cell compartment far from the main inflammation site in CD fibroblasts from skin explants. We analyzed the cell shape, actin organization, focal adhesion number, focal adhesion proteins, LPP sub-cellular distribution and adhesion to fibronectin of fibroblasts obtained from CD patients on a Gluten-Free Diet (GFD and controls, without and with treatment with A-gliadin peptide P31-43. We observed a "CD cellular phenotype" in these fibroblasts, characterized by an altered cell shape and actin organization, increased number of focal adhesions, and altered intracellular LPP protein distribution. The treatment of controls fibroblasts with gliadin peptide P31-43 mimics the CD cellular phenotype regarding the cell shape, adhesion capacity, focal adhesion number and LPP sub-cellular distribution, suggesting a close association between these alterations and CD pathogenesis.

  1. Toxicity of cadmium in Japanese quail: Evaluation of body weight, hepatic and renal function, and cellular immune response

    International Nuclear Information System (INIS)

    Cadmium (Cd) is an environmental pollutant that is able to alter the immune function. Previous studies have shown that, in mammals, chronic exposure to Cd decreases the release of macrophagic cytokines such as IL1 and TNα and decreases phagocytosis activity. On the other hand contradictory results showed an increase in the humoral response. The cellular response could be decreased by exposure to Cd. These alterations were observed in mammals. The present study aimed to investigate some of the toxic effects of Cd exposure in birds. In particular, the main objective of this work was to elucidate the effects of exposure to this pollutant on the cellular immune function of the Japanese quail as a model for the study of toxicity in animals exposed in nature. The animals were exposed to the metal (100 ppm, per os) during development, i.e., from 1 to 28 days old. Body weight, biochemical parameters, and cellular immune response were measured during and at the end of treatment. The results showed that the exposure to Cd for 28 days significantly reduced the body weight and induced hepatic toxicity. The kidney function and cellular immune response were not affected by the Cd exposure

  2. Cytokine expression and signaling in drug-induced cellular senescence

    Czech Academy of Sciences Publication Activity Database

    Nováková, Zora; Hubáčková, Soňa; Košař, Martin; Janderová-Rossmeislová, Lenka; Dobrovolná, Jana; Vašicová, Pavla; Vančurová, Markéta; Hořejší, Zuzana; Hozák, Pavel; Bartek, Jiří; Hodný, Zdeněk

    2010-01-01

    Roč. 29, č. 2 (2010), s. 273-284. ISSN 0950-9232 R&D Projects: GA AV ČR IAA500390501; GA ČR GA204/08/1418; GA MŠk LC545 Grant ostatní: EC(XE) TRIREME Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z50200510 Keywords : cellular senescence * cytokines * JAK/STAT signaling pathway Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 7.414, year: 2010

  3. Radiation-induced preventive bystander response and adaptive response

    International Nuclear Information System (INIS)

    Radiation-induced bystander response (BR) is a phenomenon not observed in cells irradiated directly but in cells nearby. Recently, the relationship between BR and adaptive response (AR) has been studied and BR is suggested to be one of important mechanisms involved in AR induction through key molecules like reactive oxygen (RO) and nitrogen species. In this paper, the possible contribution of BR to AR is discussed on recent findings including author's ones. Many biological responses in bystander cells, cultured tissues and mice by cell-cell communication molecules such as cytokines and nitrogen oxide (NO) have been elucidated for BR to involve the cell death, sister chromatid exchange, chromosome instability, mutation, increased/ decreased p53 level, etc. However, BR has been recently found to contain biologically favorable events like the increase of radio-resistance and of cellular take rate and decrease of micronucleus formation through NO by X-ray and HIMAC C-ion. AR is observed in irradiated cell population with previous exposure to low dose and involves the above mentioned biologically favorable responses, which having lead to the possible interrelationship between BR and AR. Together with findings obtained hitherto, hypothesized is that AR is induced in bystander cells through a sequence of signals of evoked radicals like RO/ NO by pre-irradiation, and of consequent intermediating molecules like transforming growth factor (TGF)-1, tumor necrosis factor (TNF), interleukin (IL)-1 and estrogen to activate NF-KB for inducing COX-2 and NO synthase, which resulting in stimulation of damaged DNA repairing mechanism and of mitogen-activated protein kinase (MAPK) cascade that constructs the signaling between plasma membrane and nucleus. (K.T.)

  4. Sand fly salivary proteins induce strong cellular immunity in a natural reservoir of visceral leishmaniasis with adverse consequences for Leishmania.

    Science.gov (United States)

    Collin, Nicolas; Gomes, Regis; Teixeira, Clarissa; Cheng, Lily; Laughinghouse, Andre; Ward, Jerrold M; Elnaiem, Dia-Eldin; Fischer, Laurent; Valenzuela, Jesus G; Kamhawi, Shaden

    2009-05-01

    Immunity to a sand fly salivary protein protects against visceral leishmaniasis (VL) in hamsters. This protection was associated with the development of cellular immunity in the form of a delayed-type hypersensitivity response and the presence of IFN-gamma at the site of sand fly bites. To date, there are no data available regarding the cellular immune response to sand fly saliva in dogs, the main reservoirs of VL in Latin America, and its role in protection from this fatal disease. Two of 35 salivary proteins from the vector sand fly Lutzomyia longipalpis, identified using a novel approach termed reverse antigen screening, elicited strong cellular immunity in dogs. Immunization with either molecule induced high IgG(2) antibody levels and significant IFN-gamma production following in vitro stimulation of PBMC with salivary gland homogenate (SGH). Upon challenge with uninfected or infected flies, immunized dogs developed a cellular response at the bite site characterized by lymphocytic infiltration and IFN-gamma and IL-12 expression. Additionally, SGH-stimulated lymphocytes from immunized dogs efficiently killed Leishmania infantum chagasi within autologous macrophages. Certain sand fly salivary proteins are potent immunogens obligatorily co-deposited with Leishmania parasites during transmission. Their inclusion in an anti-Leishmania vaccine would exploit anti-saliva immunity following an infective sand fly bite and set the stage for a protective anti-Leishmania immune response. PMID:19461875

  5. Sand fly salivary proteins induce strong cellular immunity in a natural reservoir of visceral leishmaniasis with adverse consequences for Leishmania.

    Directory of Open Access Journals (Sweden)

    Nicolas Collin

    2009-05-01

    Full Text Available Immunity to a sand fly salivary protein protects against visceral leishmaniasis (VL in hamsters. This protection was associated with the development of cellular immunity in the form of a delayed-type hypersensitivity response and the presence of IFN-gamma at the site of sand fly bites. To date, there are no data available regarding the cellular immune response to sand fly saliva in dogs, the main reservoirs of VL in Latin America, and its role in protection from this fatal disease. Two of 35 salivary proteins from the vector sand fly Lutzomyia longipalpis, identified using a novel approach termed reverse antigen screening, elicited strong cellular immunity in dogs. Immunization with either molecule induced high IgG(2 antibody levels and significant IFN-gamma production following in vitro stimulation of PBMC with salivary gland homogenate (SGH. Upon challenge with uninfected or infected flies, immunized dogs developed a cellular response at the bite site characterized by lymphocytic infiltration and IFN-gamma and IL-12 expression. Additionally, SGH-stimulated lymphocytes from immunized dogs efficiently killed Leishmania infantum chagasi within autologous macrophages. Certain sand fly salivary proteins are potent immunogens obligatorily co-deposited with Leishmania parasites during transmission. Their inclusion in an anti-Leishmania vaccine would exploit anti-saliva immunity following an infective sand fly bite and set the stage for a protective anti-Leishmania immune response.

  6. Interaction of heavy ions with nuclear chromatin: Spatiotemporal investigations of biological responses in a cellular environment

    International Nuclear Information System (INIS)

    Ion beams offer the possibility to generate strictly localized DNA lesions within subregions of a cell nucleus. The distribution of the ion-induced damage can be indirectly visualized by immunocytochemical detection of repair-related proteins as radiation-induced foci. The proteins analyzed here were the double-strand break marker γ-H2AX, the excision repair and replication protein PCNA and the cell cycle regulator CDKN1A. A newly developed adjustable sample holder is now used to apply an irradiation geometry characterized by a small angle between the plane of the cellular monolayer and the incoming ion beam. This allows the spatial analysis of protein accumulations along ion trajectories, revealing an unexpected clustering after irradiation with low-energy zinc ions. The patterns of protein aggregation observed show considerable intrinsic variability, but similar patterns of protein clustering were obtained for functionally different proteins irrespective of the type of ion beam applied, confirming previous observations for lower and higher LET beams. Foci sizes within ion tracks were found to be larger for γ-H2AX foci in comparison to CDKN1A foci, in agreement with the known histone H2AX phosphorylation response. The results suggest that not the pattern of dose deposition but the underlying chromatin structure determines the distribution of protein clusters along tracks. Therefore, the requirement of time-lapse studies using live cells is emphasized for future studies on chromatin movement as a potential component of the DNA damage response

  7. Cellular responses to disruption of the permeability barrier in a three-dimensional organotypic epidermal model

    International Nuclear Information System (INIS)

    Repeated injury to the stratum corneum of mammalian skin (caused by friction, soaps, or organic solvents) elicits hyperkeratosis and epidermal thickening. Functionally, these changes serve to restore the cutaneous barrier and protect the organism. To better understand the molecular and cellular basis of this response, we have engineered an in vitro model of acetone-induced injury using organotypic epidermal cultures. Rat epidermal keratinocytes (REKs), grown on a collagen raft in the absence of any feeder fibroblasts, developed all the hallmarks of a true epidermis including a well-formed cornified layer. To induce barrier injury, REK cultures were treated with intermittent 30-s exposures to acetone then were fixed and paraffin-sectioned. After two exposures, increased proliferation (Ki67 and BrdU staining) was observed in basal and suprabasal layers. After three exposures, proliferation became confined to localized buds in the basal layer and increased terminal differentiation was observed (compact hyperkeratosis of the stratum corneum, elevated levels of K10 and filaggrin, and heightened transglutaminase activity). Thus, barrier disruption causes epidermal hyperplasia and/or enhances differentiation, depending upon the extent and duration of injury. Given that no fibroblasts are present in the model, the ability to mount a hyperplastic response to barrier injury is an inherent property of keratinocytes

  8. Response of MICROTOX organisms to leachates of autoclaved cellular concrete

    International Nuclear Information System (INIS)

    The MICROTOX bioassay, a toxicity test involving bioluminescent microorganisms, was conducted on aqueous leachates derived from a construction material made using coal fly ash as the key siliceous ingredient. The material is known as autoclaved cellular concrete (ACC). The test indicated an absence of toxic effects attributable to soluble species, which included the priority heavy metals in the filtered leachates. Toxic or inhibitive effects on the test bacteria were observed for the toxicity characteristic leaching procedure (TCLP) leachates, but this was probably due to acetic acid in the extractant rather than the solubilized metals. The ASTM (distilled-deionized water extractant) and simulated acid rain leachates, by comparison, produced a repeatable stimulative effect. Stimulation observed in the form of enhanced light output may be a manifestation of hormesis, a phenomenon reportedly caused by exposure to extremely low concentrations (part-per-billion range) of otherwise toxic agents such as heavy metals

  9. Response of MICROTOX organisms to leachates of autoclaved cellular concrete

    Energy Technology Data Exchange (ETDEWEB)

    Latona, M.C.; Neufeld, R.D.; Hu, W.; Kelly, C.; Vallejo, L.E. [Univ. of Pittsburgh, PA (United States). Dept. of Civil and Environmental Engineering

    1997-08-01

    The MICROTOX bioassay, a toxicity test involving bioluminescent microorganisms, was conducted on aqueous leachates derived from a construction material made using coal fly ash as the key siliceous ingredient. The material is known as autoclaved cellular concrete (ACC). The test indicated an absence of toxic effects attributable to soluble species, which included the priority heavy metals in the filtered leachates. Toxic or inhibitive effects on the test bacteria were observed for the toxicity characteristic leaching procedure (TCLP) leachates, but this was probably due to acetic acid in the extractant rather than the solubilized metals. The ASTM (distilled-deionized water extractant) and simulated acid rain leachates, by comparison, produced a repeatable stimulative effect. Stimulation observed in the form of enhanced light output may be a manifestation of hormesis, a phenomenon reportedly caused by exposure to extremely low concentrations (part-per-billion range) of otherwise toxic agents such as heavy metals.

  10. Injury-induced immune responses in Hydra.

    Science.gov (United States)

    Wenger, Yvan; Buzgariu, Wanda; Reiter, Silke; Galliot, Brigitte

    2014-08-01

    The impact of injury-induced immune responses on animal regenerative processes is highly variable, positive or negative depending on the context. This likely reflects the complexity of the innate immune system that behaves as a sentinel in the transition from injury to regeneration. Early-branching invertebrates with high regenerative potential as Hydra provide a unique framework to dissect how injury-induced immune responses impact regeneration. A series of early cellular events likely require an efficient immune response after amputation, as antimicrobial defence, epithelial cell stretching for wound closure, migration of interstitial progenitors toward the wound, cell death, phagocytosis of cell debris, or reconstruction of the extracellular matrix. The analysis of the injury-induced transcriptomic modulations of 2636 genes annotated as immune genes in Hydra identified 43 genes showing an immediate/early pulse regulation in all regenerative contexts examined. These regulations point to an enhanced cytoprotection via ROS signaling (Nrf, C/EBP, p62/SQSMT1-l2), TNFR and TLR signaling (TNFR16-like, TRAF2l, TRAF5l, jun, fos-related, SIK2, ATF1/CREB, LRRC28, LRRC40, LRRK2), proteasomal activity (p62/SQSMT1-l1, Ced6/Gulf, NEDD8-conjugating enzyme Ubc12), stress proteins (CRYAB1, CRYAB2, HSP16.2, DnaJB9, HSP90a1), all potentially regulating NF-κB activity. Other genes encoding immune-annotated proteins such as NPYR4, GTPases, Swap70, the antiproliferative BTG1, enzymes involved in lipid metabolism (5-lipoxygenase, ACSF4), secreted clotting factors, secreted peptidases are also pulse regulated upon bisection. By contrast, metalloproteinases and antimicrobial peptide genes largely follow a context-dependent regulation, whereas the protease inhibitor α2macroglobulin gene exhibits a sustained up-regulation. Hence a complex immune response to injury is linked to wound healing and regeneration in Hydra. PMID:25086685

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

    Directory of Open Access Journals (Sweden)

    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. Repeatedly administered antidepressant drugs modulate humoral and cellular immune response in mice through action on macrophages.

    Science.gov (United States)

    Nazimek, Katarzyna; Kozlowski, Michael; Bryniarski, Pawel; Strobel, Spencer; Bryk, Agata; Myszka, Michal; Tyszka, Anna; Kuszmiersz, Piotr; Nowakowski, Jaroslaw; Filipczak-Bryniarska, Iwona

    2016-08-01

    Depression is associated with an altered immune response, which could be normalized by antidepressant drugs. However, little is known about the influence of antidepressants on the peripheral immune response and function of macrophages in individuals not suffering from depression. Our studies were aimed at determining the influence of antidepressant drugs on the humoral and cellular immune response in mice. Mice were treated intraperitoneally with imipramine, fluoxetine, venlafaxine, or moclobemide and contact immunized with trinitrophenyl hapten followed by elicitation and measurement of contact sensitivity by ear swelling response. Peritoneal macrophages from drug-treated mice were either pulsed with sheep erythrocytes or conjugated with trinitrophenyl and transferred into naive recipients to induce humoral or contact sensitivity response, respectively. Secretion of reactive oxygen intermediates, nitric oxide, and cytokines by macrophages from drug-treated mice was assessed, respectively, in chemiluminometry, Griess-based colorimetry and enzyme-linked immunosorbent assay, and the expression of macrophage surface markers was analyzed cytometrically. Treatment of mice with fluoxetine, venlafaxine, and moclobemide results in suppression of humoral and cell-mediated immunity with a reduction of the release of macrophage proinflammatory mediators and the expression of antigen-presentation markers. In contrast, treatment with imipramine enhanced the humoral immune response and macrophage secretory activity but slightly suppressed active contact sensitivity. Our studies demonstrated that systemically delivered antidepressant drugs modulate the peripheral humoral and cell-mediated immune responses, mostly through their action on macrophages. Imipramine was rather proinflammatory, whereas other tested drugs expressed immunosuppressive potential. Current observations may be applied to new therapeutic strategies dedicated to various disorders associated with excessive

  13. 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.

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

    Science.gov (United States)

    Kirkconnell, Killeen S; Paulsen, Michelle T; Magnuson, Brian; Bedi, Karan; Ljungman, Mats

    2016-01-01

    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. PMID:27230646

  15. Engagement of CD81 induces ezrin tyrosine phosphorylation and its cellular redistribution with filamentous actin

    Energy Technology Data Exchange (ETDEWEB)

    Coffey, Greg P.; Rajapaksa, Ranjani; Liu, Raymond; Sharpe, Orr; Kuo, Chiung-Chi; Wald Krauss, Sharon; Sagi, Yael; Davis, R. Eric; Staudt, Louis M.; Sharman, Jeff P.; Robinson, William H.; Levy, Shoshana

    2009-06-09

    CD81 is a tetraspanin family member involved in diverse cellular interactions in the immune and nervous systems and in cell fusion events. However, the mechanism of action of CD81 and of other tetraspanins has not been defined. We reasoned that identifying signaling molecules downstream of CD81 would provide mechanistic clues. We engaged CD81 on the surface of Blymphocytes and identified the induced tyrosine-phosphorylated proteins by mass spectrometry. This analysis showed that the most prominent tyrosine phosphorylated protein was ezrin, an actin binding protein and a member of the ezrin-radixin-moesin family. We also found that CD81 engagement induces spleen tyrosine kinase (Syk) and that Syk was involved in tyrosine phosphorylation of ezrin. Ezrin colocalized with CD81 and F-actin upon stimulation and this association was disrupted when Syk activation was blocked. Taken together, these studies suggest a model in which CD81 interfaces between the plasma membrane and the cytoskeleton by activating Syk, mobilizing ezrin, and recruiting F-actin to facilitate cytoskeletal reorganization and cell signaling. This may be a mechanism explaining the pleiotropic effects induced in response to stimulating cells by anti-CD81 antibodies or by the hepatitis C virus, which uses this molecule as its key receptor.

  16. Hyperglycemia Induces Cellular Hypoxia through Production of Mitochondrial ROS Followed by Suppression of Aquaporin-1.

    Directory of Open Access Journals (Sweden)

    Kiminori Sada

    Full Text Available We previously proposed that hyperglycemia-induced mitochondrial reactive oxygen species (mtROS generation is a key event in the development of diabetic complications. Interestingly, some common aspects exist between hyperglycemia and hypoxia-induced phenomena. Thus, hyperglycemia may induce cellular hypoxia, and this phenomenon may also be involved in the pathogenesis of diabetic complications. In endothelial cells (ECs, cellular hypoxia increased after incubation with high glucose (HG. A similar phenomenon was observed in glomeruli of diabetic mice. HG-induced cellular hypoxia was suppressed by mitochondria blockades or manganese superoxide dismutase (MnSOD overexpression, which is a specific SOD for mtROS. Overexpression of MnSOD also increased the expression of aquaporin-1 (AQP1, a water and oxygen channel. AQP1 overexpression in ECs suppressed hyperglycemia-induced cellular hypoxia, endothelin-1 and fibronectin overproduction, and apoptosis. Therefore, hyperglycemia-induced cellular hypoxia and mtROS generation may promote hyperglycemic damage in a coordinated manner.

  17. Radiation-induced changes in cellularity and proliferation in human oral mucosa

    International Nuclear Information System (INIS)

    Purpose: To quantify the oral mucosal cell density and proliferation rate during conventional radiotherapy of head-and-neck tumors and to compare these parameters with clinical scoring of oral mucositis. Methods and Materials: Between 1996 and 1999, 22 patients were included in this study. Mucosal biopsies were taken before or during the radiotherapy course (5 x 2 Gy/wk). Biopsies were incubated in vitro with tritiated thymidine immediately after excision to label DNA-synthesizing cells. Results: Epithelial cell density followed a biphasic radiation response. A steep decrease to about 50% of the preirradiation value (1000 cells/mm epithelium) during Week 1 was followed by a more gradual loss to about 400 cells at the end of treatment. The initial phase was based on the depression of proliferation, with 5-10 labeled cells/mm at the end of Week 1 vs. 60 labeled cells/mm in controls. Subsequently, proliferation was partially restituted at 20 labeled cells/mm. A significant difference in cell numbers was seen between Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Grade 0 (∼850 cell/mm) and Grade 2 (325/mm) or Grade 3 (370/mm). No significant differences were observed between reaction grades 1, 2, and 3. Conclusion: Conventionally fractionated radiotherapy induces a rapid suppression in cell production in Week 1, which results in a prompt reduction in cell numbers. Subsequently, a partial restoration of proliferation significantly reduces the rate of cell loss. These processes clearly precede the clinical response. Regeneration, defined as restoration of cellularity, is already under way when the maximal clinical response is observed. Clinical reaction grading corresponds poorly to cellular density measures during conventional fractionation

  18. Inhibition of hypochlorous acid-induced cellular toxicity by nitrite

    Science.gov (United States)

    Whiteman, Matthew; Hooper, D. Craig; Scott, Gwen S.; Koprowski, Hilary; Halliwell, Barry

    2002-09-01

    Chronic inflammation results in increased nitrogen monoxide (NO) formation and the accumulation of nitrite (NO). Neutrophils stimulated by various inflammatory mediators release myeloperoxidase to produce the cytotoxic agent hypochlorous acid (HOCl). Exposure of chondrocytic SW1353 cells to HOCl resulted in a concentration- and time-dependent loss in viability, ATP, and glutathione levels. Treatment of cells with NO but not nitrate (NO) substantially decreased HOCl-dependent cellular toxicity even when NO was added at low (μM) concentrations. In contrast, NO alone (even at 1 mM concentrations) did not affect cell viability or ATP and glutathione levels. These data suggest that NO accumulation at chronic inflammatory sites, where both HOCl and NO are overproduced, may be cytoprotective against damage caused by HOCl. We propose that this is because HOCl is removed by reacting with NO to give nitryl chloride (NO2Cl), which is less damaging in our cell system. inflammation | cell toxicity | nitryl chloride | nitric oxide | arthritis

  19. 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.

  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. 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. PMID:24476337

  2. Hexachlorobenzene induces deregulation of cellular growth in rat liver

    International Nuclear Information System (INIS)

    Hexachlorobenzene (HCB) is an organochlorine pesticide widely distributed in the biosphere. The aim of the present study was to investigate the effect of HCB on the homeostasis of liver cell growth, analyzing parameters of cell proliferation and apoptosis, in HCB (0.1, 1, 10 and 100 mg/kg body weight)-treated rats, during 4 weeks. Cell proliferation and ERK1/2 phosphorylation, associated with survival mechanisms, were increased at HCB 100 mg/kg. The pesticide increased the number of apoptotic cells, and the activation of caspase-3, -9 and -8, in a dose-dependent manner, suggesting that HCB-induced apoptosis is mediated by caspases. Increased Fas and FasL protein levels indicate that the death receptor pathway is also involved. This process is associated with decreased Bid, and increased cytosolic cytochrome c protein levels. Transforming growth factor-beta1 (TGF-β1) intervenes in apoptotic and/or proliferative processes in hepatocytes. TGF-β1 cDNA and protein levels are dose-dependently increased, suggesting that this cytokine might be involved in HCB-induced dysregulation of cell proliferation and apoptosis. In conclusion, this study reports for the first time that HCB induces loss of the homeostatic balance between cell growth and cell death in rat liver. Induced apoptosis occurs by mechanisms involving signals emanating from death receptors, and the mitochondrial pathway.

  3. Beyond annexin V: fluorescence response of cellular membranes to apoptosis.

    Science.gov (United States)

    Demchenko, Alexander P

    2013-03-01

    Dramatic changes in the structure of cell membranes on apoptosis allow easy, sensitive and non-destructive analysis of this process with the application of fluorescence methods. The strong plasma membrane asymmetry is present in living cells, and its loss on apoptosis is commonly detected with the probes interacting strongly and specifically with phosphatidylserine (PS). This phospholipid becomes exposed to the cell surface, and the application of annexin V labeled with fluorescent dye is presently the most popular tool for its detection. Several methods have been suggested recently that offer important advantages over annexin V assay with the ability to study apoptosis by spectroscopy of cell suspensions, flow cytometry and confocal or two-photon microscopy. The PS exposure marks the integrated changes in the outer leaflet of cell membrane that involve electrostatic potential and hydration, and the attempts are being made to provide direct probing of these changes. This review describes the basic mechanisms underlying the loss of membrane asymmetry during apoptosis and discusses, in comparison with the annexin V-binding assay, the novel fluorescence techniques of detecting apoptosis on cellular membrane level. In more detail we describe the detection method based on smart fluorescent dye F2N12S incorporated into outer leaflet of cell membrane and reporting on apoptotic cell transformation by easily detectable change of the spectral distribution of fluorescent emission. It can be adapted to any assay format. PMID:22797774

  4. Adult Drosophila melanogaster evolved for antibacterial defense invest in infection-induced expression of both humoral and cellular immunity genes

    Directory of Open Access Journals (Sweden)

    McGraw Elizabeth A

    2011-08-01

    Full Text Available Abstract Background While the transcription of innate immunity genes in response to bacterial infection has been well-characterised in the Drosophila model, we recently demonstrated the capacity for such transcription to evolve in flies selected for improved antibacterial defense. Here we use this experimental system to examine how insects invest in constitutive versus infection-induced transcription of immunity genes. These two strategies carry with them different consequences with respect to energetic and pleiotropic costs and may be more or less effective in improving defense depending on whether the genes contribute to humoral or cellular aspects of immunity. Findings Contrary to expectation we show that selection preferentially increased the infection-induced expression of both cellular and humoral immunity genes. Given their functional roles, infection induced increases in expression were expected for the humoral genes, while increases in constitutive expression were expected for the cellular genes. We also report a restricted ability to improve transcription of immunity genes that is on the order of 2-3 fold regardless of total transcription level of the gene. Conclusions The evolved increases in infection-induced expression of the cellular genes may result from specific cross talk with humoral pathways or from generalised strategies for enhancing immunity gene transcription. A failure to see improvements in constitutive expression of the cellular genes suggests either that increases might come at too great a cost or that patterns of expression in adults are decoupled from the larval phase where increases would be most effective. The similarity in fold change increase across all immunity genes may suggest a shared mechanism for the evolution of increased transcription in small, discrete units such as duplication of cis-regulatory elements.

  5. Characterization of humoral and cellular immune responses in patients with human papilloma virus

    International Nuclear Information System (INIS)

    A descriptive and cross-sectional study was carried out in 30 females infected with the human papilloma virus, attended in the office of Immunology of the Specialty Polyclinic belonging to 'Saturnino Lora' Provincial Clinical Surgical Teaching Hospital in Santiago de Cuba, from June 2009 to June 2010, in order to characterize them according to immune response. To evaluate the humoral and cellular immune response rosetting assay and quantification of immunoglobulins were used respectively. Women between 25-36 years of age (40 %) infected with this virus, especially those coming from urban areas, prevailed in the series, and a significant decrease of the cellular response as compared to the humoral response was evidenced

  6. Cellular stress responses for monitoring and modulating ageing

    DEFF Research Database (Denmark)

    Demirovic, Dino; Schnebert, Sylvianne; Nizard, Carine;

    2013-01-01

    protectors and stimulators of homeodynamics, and create a kind of “gold-standard” for monitoring the efficacy of other potential antiageing and pro-survival natural and synthetic compounds. We have so far standardised an effective method for detecting all seven stress response pathways, by several...

  7. Programming and Reprogramming Cellular Age in the Era of Induced Pluripotency.

    Science.gov (United States)

    Studer, Lorenz; Vera, Elsa; Cornacchia, Daniela

    2015-06-01

    The ability to reprogram adult somatic cells back to pluripotency presents a powerful tool for studying cell-fate identity and modeling human disease. However, the reversal of cellular age during reprogramming results in an embryonic-like state of induced pluripotent stem cells (iPSCs) and their derivatives, which presents specific challenges for modeling late onset disease. This age reset requires novel methods to mimic age-related changes but also offers opportunities for studying cellular rejuvenation in real time. Here, we discuss how iPSC research may transform studies of aging and enable the precise programming of cellular age in parallel to cell-fate specification. PMID:26046759

  8. Identification of human genes involved in cellular responses to ionizing radiation: molecular and cellular studies of gene encoding the p68 helicase in mammalian cells

    International Nuclear Information System (INIS)

    Cells submitted to genotoxic factors -like IR- activate several and important mechanisms such as repair, cell cycle arrest or 'apoptosis' to maintain genetic integrity. So, the damaged cells will induce many and different genes. The human transcriptome analysis by 'SSH' method in a human breast carcinoma cell line MCF7 γ-irradiated versus not irradiated, allowed to identify about one hundred genes. Among of these genes, we have focused our study on a radio-induced gene encoding the p68 helicase. In the conditions of irradiation used, our results show that the kinetic and the regulation of this gene expression differs between the nature of radiations used. Indeed, in γ-irradiated mammalian cells, ATM, a protein kinase activated by DSB and IR, is required to induce quickly P68 gene via the important transcription factor p53 stabilized by IR. In the case of UVC-irradiated cells, the P68 gene induction is late and the intracellular signalling pathway that lead to this induction is independent from the p53 protein. Finally, we show that the p68 protein under-expression is responsible for an increased radiosensitivity of MCF7 cells. Consequently, we can postulate that the p68 protein is involved in cellular responses to radiations to reduce the increased radiosensitivity of cells exposed to γ-rays. (author)

  9. The mucosal cellular response to infection with Ancylostoma ceylanicum

    OpenAIRE

    Alkazmi, L.M.M.; Dehlawi, M.S.; BEHNKE, J. M.

    2008-01-01

    Although hookworms are known to stimulate inflammatory responses in the intestinal mucosa of their hosts, there is little quantitative data on this aspect of infection. Here we report the results of experiments conducted in hamsters infected with Ancylostoma ceylanicum. Infection resulted in a marked increase in goblet cells in the intestinal mucosa, which was dependent on the number of adult worms present and was sustained as long as worms persisted (over 63 days) but returned to baseline le...

  10. Human T-cell leukemia virus type 1 tax attenuates the ATM-mediated cellular DNA damage response.

    Science.gov (United States)

    Chandhasin, Chandtip; Ducu, Razvan I; Berkovich, Elijahu; Kastan, Michael B; Marriott, Susan J

    2008-07-01

    Genomic instability, a hallmark of leukemic cells, is associated with malfunctioning cellular responses to DNA damage caused by defective cell cycle checkpoints and/or DNA repair. Adult T-cell leukemia, which can result from infection with human T-cell leukemia virus type 1 (HTLV-1), is associated with extensive genomic instability that has been attributed to the viral oncoprotein Tax. How Tax influences cellular responses to DNA damage to mediate genomic instability, however, remains unclear. Therefore, we investigated the effect of Tax on cellular pathways involved in recognition and repair of DNA double-strand breaks. Premature attenuation of ATM kinase activity and reduced association of MDC1 with repair foci were observed in Tax-expressing cells. Following ionizing radiation-induced S-phase checkpoint activation, Tax-expressing cells progressed more rapidly than non-Tax-expressing cells toward DNA replication. These results demonstrate that Tax expression may allow premature DNA replication in the presence of genomic lesions. Attempts to replicate in the presence of these lesions would result in gradual accumulation of mutations, leading to genome instability and cellular transformation. PMID:18434398

  11. Gadd45a, a p53- and BRCA1-regulated stress protein, in cellular response to DNA damage

    International Nuclear Information System (INIS)

    Mammalian cells exhibit complex, but intricate cellular responses to genotoxic stress, including cell cycle checkpoints, DNA repair and apoptosis. Inactivation of these important biological events may result in genomic instability and cell transformation, as well as alterations of therapeutic sensitivity. Gadd45a, a p53- and BRCA1-regulated stress-inducible gene, has been characterized as one of the important players that participate in cellular response to a variety of DNA damage agents. Interestingly, the signaling machinery that regulates Gadd45a induction by genotoxic stress involves both p53-dependent and -independent pathways; the later may employ BRCA1-related or MAP kinase-mediated signals. Gadd45a protein has been reported to interact with multiple important cellular proteins, including Cdc2 protein kinase, proliferating cell nuclear antigen (PCNA), p21Waf1/Cip1 protein, core histone protein and MTK/MEKK4, an up-stream activator of the JNK/SAPK pathway, indicating that Gadd45a may play important roles in the control of cell cycle checkpoint, DNA repair process, and signaling transduction. The importance of Gadd45a in maintaining genomic integrity is well manifested by the demonstration that disruption of endogenous Gadd45a in mice results in genomic instability and increased carcinogenesis. Therefore, Gadd45a appears to be an important component in the cellular defense network that is required for maintenance of genomic stability

  12. Cellular response to low Gamma-ray doses

    International Nuclear Information System (INIS)

    Lymphocytes, obtained from healthy donors, were exposed to a low strength gamma-ray field to determine heat shock protein expression in function of radiation dose. Protein identification was carried out using mAb raised against Hsp70 and Hsc70.Hsp70 protein was detected after lymphocyte irradiation. In all cases, an increasing trend of relative amounts of Hsp70 in function to irradiation time was observed. After 1.25 c Gy gamma-ray dose, lymphocytes expressed Hsp70 protein, indicating a threshold response to gamma rays. (Author)

  13. Effect of the nano-bio interface on the genotoxicity of titanium dioxide nanoparticles and associated cellular responses

    Science.gov (United States)

    Prasad, Raju Yashaswi

    Several toxicological studies have shown that titanium dioxide nanoparticles (nano-TiO2), one of the most widely produced engineered nanoparticles, can induce genotoxicity; however, potential adverse health effects associated with their physicochemical properties are not fully understood. Proteins in a biological medium can adsorb to the surface of the nanoparticle resulting in the formation of a protein corona that can alter the physicochemical properties of the particle. Furthermore, the protein corona may impact the interaction between nanoparticles and cells, referred to as the nano-bio interface, effecting the uptake, distribution, and toxicity of the particles. Despite the potential influence of the composition of the biological medium on the physicochemical properties and genotoxicity of titanium dioxide nanoparticles, the majority of studies have not examined systematically the influence of medium composition on protein corona, genotoxicity, and cellular responses. In this dissertation we tested the overall hypothesis that titanium dioxide nanoparticles in medium that produces the smallest agglomerates would be taken up into cells and induce genotoxicity, and that exposure would initiate the signaling of key mediators of a DNA damage and inflammation response. Three major findings were shown in this study: 1) Protein corona formation on the surface of nano-TiO2 can impact the nano-bio interface and change cellular interaction. 2) Smaller agglomerates of nano-TiO2 are taken up more by cells without inducing cell cycle arrest, thereby allowing induced DNA damage to be processed into micronuclei in BEAS-2B cells. 3) Nano-TiO 2 in medium that facilitates increased cellular interaction induces the upregulation of the ATM-Chk2 DNA damage response (similar to ionizing radiation) and NF-kappaB inflammation pathways. Taken together, our research provides a systematic examination of the physicochemical properties, genotoxicity, and cellular responses induced by

  14. Cellular adaptation as an important response during chemical carcinogenesis

    International Nuclear Information System (INIS)

    Since disease processes are largely expressions of how living organisms react and respond to perturbations in the external and internal environments, adaptive or protective responses and their modulations and mechanisms are of the greatest concern in fundamental studies of disease pathogenesis. Such considerations are also of the greatest relevance in toxicology, including how living organisms respond to low levels of single and multiple xenobiotics and radiations. As the steps and mechanisms during cancer development are studied in greater depth, phenomena become apparent that suggest that adaptive reactions and responses may play important or even critical roles in the process of carcinogenesis. The question becomes whether the process of carcinogenesis is fundamentally an adversarial one (i.e., an abnormal cell in a vulnerable host), or is it more in the nature of a physiological selection or differentiation, which has survival value for the host as an adaptive phenomena? The very early initial interactions of mutagenic chemical carcinogens, radiations and viruses with DNA prejudice most to consider the adversarial 'abnormal' view as the appropriate one. Yet, the unusually common nature of the earliest altered rare cells that appear during carcinogenesis, their unusually bland nature, and their spontaneous differentiation to normal-appearing adult liver should be carefully considered

  15. Tumor suppressor BTG1 promotes PRMT1-mediated ATF4 function in response to cellular stress

    Science.gov (United States)

    Tijchon, Esther; van Ingen Schenau, Dorette; van Emst, Liesbeth; Levers, Marloes; Palit, Sander A.L.; Rodenbach, Caroline; Poelmans, Geert; Hoogerbrugge, Peter M.; Shan, Jixiu; Kilberg, Michael S.; Scheijen, Blanca; van Leeuwen, Frank N.

    2016-01-01

    Cancer cells are frequently exposed to physiological stress conditions such as hypoxia and nutrient limitation. Escape from stress-induced apoptosis is one of the mechanisms used by malignant cells to survive unfavorable conditions. B-cell Translocation Gene 1 (BTG1) is a tumor suppressor that is frequently deleted in acute lymphoblastic leukemia and recurrently mutated in diffuse large B cell lymphoma. Moreover, low BTG1 expression levels have been linked to poor outcome in several solid tumors. How loss of BTG1 function contributes to tumor progression is not well understood. Here, using Btg1 knockout mice, we demonstrate that loss of Btg1 provides a survival advantage to primary mouse embryonic fibroblasts (MEFs) under stress conditions. This pro-survival effect involves regulation of Activating Transcription Factor 4 (ATF4), a key mediator of cellular stress responses. We show that BTG1 interacts with ATF4 and positively modulates its activity by recruiting the protein arginine methyl transferase PRMT1 to methylate ATF4 on arginine residue 239. We further extend these findings to B-cell progenitors, by showing that loss of Btg1 expression enhances stress adaptation of mouse bone marrow-derived B cell progenitors. In conclusion, we have identified the BTG1/PRMT1 complex as a new modifier of ATF4 mediated stress responses. PMID:26657730

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

    Directory of Open Access Journals (Sweden)

    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.

  17. Avian renal proximal tubule urate secretion is inhibited by cellular stress-induced AMP-activated protein kinase.

    Science.gov (United States)

    Bataille, Amy M; Maffeo, Carla L; Renfro, J Larry

    2011-06-01

    Urate is a potent antioxidant at high concentrations but it has also been associated with a wide variety of health risks. Plasma urate concentration is determined by ingestion, production, and urinary excretion; however, factors that regulate urate excretion remain uncertain. The objective of this study was to determine whether cellular stress, which has been shown to affect other renal transport properties, modulates urate secretion in the avian renal proximal tubule. Chick kidney proximal tubule epithelial cell primary culture monolayers were used to study the transepithelial transport of radiolabeled urate. This model allowed examination of the processes, such as multidrug resistance protein 4 (Mrp4, Abcc4), which subserve urate secretion in a functional, intact, homologous system. Our results show that the recently implicated urate efflux transporter, breast cancer resistance protein (ABCG2), does not significantly contribute to urate secretion in this system. Exposure to a high concentration of zinc for 6 h induced a cellular stress response and a striking decrease in transepithelial urate secretion. Acute exposure to zinc had no effect on transepithelial urate secretion or isolated membrane vesicle urate transport, suggesting involvement of a cellular stress adaptation. Activation of AMP-activated protein kinase (AMPK), a candidate modulator of ATP-dependent urate efflux, by 5'-aminoimidazole-4-carboxamide 1-β-d-ribo-furanoside caused a decrease in urate secretion similar to that seen with zinc-induced cellular stress. This effect was prevented with the AMPK inhibitor compound C. Notably, the decrease in urate secretion seen with zinc-induced cellular stress was also prevented by compound C, implicating AMPK in regulation of renal uric acid excretion. PMID:21429974

  18. Lethal cellular changes induced by near ultraviolet radiation

    International Nuclear Information System (INIS)

    There is clear evidence that significant quantities of lesions are induced in DNA by near UV radiation and that these lesions, although susceptible to repair, may lead to cell death because of the simultaneous disruption of DNA repair systems by the same wavelengths. No particular DNA lesion can be linked to cell death in wild type strains. However, there are good grounds for speculating that a type of near UV lesion exists which is rapidly 'fixed' as a lethal event in cells as a result of the oxygen-dependent disruption of repair. There is a strong indication that the relative ability of various near UV wavelengths to sensitize cells to heat, chemicals or other radiations is directly related to their efficiency in disrupting DNA repair systems in general. (author)

  19. The Nrf2 Activator Vinylsulfone Reduces High Glucose-Induced Neural Tube Defects by Suppressing Cellular Stress and Apoptosis.

    Science.gov (United States)

    Dong, Daoyin; Reece, E Albert; Yang, Peixin

    2016-08-01

    The nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway is one of the primary pathways responsible for the cellular defense system against oxidative stress. Oxidative stress-induced apoptosis is a causal event in diabetic embryopathy. Thus, the Nrf2 pathway may play an important role in the induction of diabetic embryopathy. In the present study, we investigated the potentially protective effect of the Nrf2 activator, vinylsulfone, on high glucose-induced cellular stress, apoptosis, and neural tube defects (NTDs). Embryonic day 8.5 (E8.5) whole mouse embryos were cultured in normal (5 mmol/L) or high (16.7 mmol/L) glucose conditions, with or without vinylsulfone. At a concentration of 10 μmol/L, vinylsulfone had an inhibitory effect on high glucose-induced NTD formation, but it was not significant. At a concentration of 20 μmol/L, vinylsulfone significantly reduced high glucose-induced NTDs. In addition, 20 μmol/L vinylsulfone abrogated the high glucose-induced oxidative stress markers lipid hydroperoxide (LPO), 4-hydroxynonenal (4-HNE), and nitrotyrosine-modified proteins. The high glucose-induced endoplasmic reticulum (ER) stress biomarkers were also suppressed by 20 μmol/L vinylsulfone through the inhibition of phosphorylated protein kinase RNA-like ER kinase (PERK), inositol requiring protein 1α (IRE1a), eukaryotic initiation factor 2α (eIF2a), upregulated C/EBP-homologous protein (CHOP), binding immunoglobulin protein (BiP), and x-box binding protein 1 (XBP1) messenger RNA splicing. Furthermore, 20 μmol/L vinylsulfone abolished caspase 3 and caspase 8 cleavage, markers of apoptosis, in embryos cultured under high glucose conditions. The Nrf2 activator, vinylsulfone, is protective against high glucose-induced cellular stress, caspase activation, and subsequent NTD formation. Our data suggest that vinylsulfone supplementation is a potential therapy for diabetes-associated neurodevelopmental defects. PMID:26802109

  20. Both Complexity and Location of DNA Damage Contribute to Cellular Senescence Induced by Ionizing Radiation

    Science.gov (United States)

    Zhang, Xurui; Ye, Caiyong; Sun, Fang; Wei, Wenjun; Hu, Burong; Wang, Jufang

    2016-01-01

    Persistent DNA damage is considered as a main cause of cellular senescence induced by ionizing radiation. However, the molecular bases of the DNA damage and their contribution to cellular senescence are not completely clear. In this study, we found that both heavy ions and X-rays induced senescence in human uveal melanoma 92–1 cells. By measuring senescence associated-β-galactosidase and cell proliferation, we identified that heavy ions were more effective at inducing senescence than X-rays. We observed less efficient repair when DNA damage was induced by heavy ions compared with X-rays and most of the irreparable damage was complex of single strand breaks and double strand breaks, while DNA damage induced by X-rays was mostly repaired in 24 hours and the remained damage was preferentially associated with telomeric DNA. Our results suggest that DNA damage induced by heavy ion is often complex and difficult to repair, thus presents as persistent DNA damage and pushes the cell into senescence. In contrast, persistent DNA damage induced by X-rays is preferentially associated with telomeric DNA and the telomere-favored persistent DNA damage contributes to X-rays induced cellular senescence. These findings provide new insight into the understanding of high relative biological effectiveness of heavy ions relevant to cancer therapy and space radiation research. PMID:27187621

  1. Both Complexity and Location of DNA Damage Contribute to Cellular Senescence Induced by Ionizing Radiation.

    Science.gov (United States)

    Zhang, Xurui; Ye, Caiyong; Sun, Fang; Wei, Wenjun; Hu, Burong; Wang, Jufang

    2016-01-01

    Persistent DNA damage is considered as a main cause of cellular senescence induced by ionizing radiation. However, the molecular bases of the DNA damage and their contribution to cellular senescence are not completely clear. In this study, we found that both heavy ions and X-rays induced senescence in human uveal melanoma 92-1 cells. By measuring senescence associated-β-galactosidase and cell proliferation, we identified that heavy ions were more effective at inducing senescence than X-rays. We observed less efficient repair when DNA damage was induced by heavy ions compared with X-rays and most of the irreparable damage was complex of single strand breaks and double strand breaks, while DNA damage induced by X-rays was mostly repaired in 24 hours and the remained damage was preferentially associated with telomeric DNA. Our results suggest that DNA damage induced by heavy ion is often complex and difficult to repair, thus presents as persistent DNA damage and pushes the cell into senescence. In contrast, persistent DNA damage induced by X-rays is preferentially associated with telomeric DNA and the telomere-favored persistent DNA damage contributes to X-rays induced cellular senescence. These findings provide new insight into the understanding of high relative biological effectiveness of heavy ions relevant to cancer therapy and space radiation research. PMID:27187621

  2. Both Complexity and Location of DNA Damage Contribute to Cellular Senescence Induced by Ionizing Radiation.

    Directory of Open Access Journals (Sweden)

    Xurui Zhang

    Full Text Available Persistent DNA damage is considered as a main cause of cellular senescence induced by ionizing radiation. However, the molecular bases of the DNA damage and their contribution to cellular senescence are not completely clear. In this study, we found that both heavy ions and X-rays induced senescence in human uveal melanoma 92-1 cells. By measuring senescence associated-β-galactosidase and cell proliferation, we identified that heavy ions were more effective at inducing senescence than X-rays. We observed less efficient repair when DNA damage was induced by heavy ions compared with X-rays and most of the irreparable damage was complex of single strand breaks and double strand breaks, while DNA damage induced by X-rays was mostly repaired in 24 hours and the remained damage was preferentially associated with telomeric DNA. Our results suggest that DNA damage induced by heavy ion is often complex and difficult to repair, thus presents as persistent DNA damage and pushes the cell into senescence. In contrast, persistent DNA damage induced by X-rays is preferentially associated with telomeric DNA and the telomere-favored persistent DNA damage contributes to X-rays induced cellular senescence. These findings provide new insight into the understanding of high relative biological effectiveness of heavy ions relevant to cancer therapy and space radiation research.

  3. Effects of localized radiotherapy upon the cellular immune response

    International Nuclear Information System (INIS)

    We delivered two regimens of fractionated doses, one of 700 rad three times in 1 week, and one of 400 rad three times a week for 3 weeks, to the left hind limbs of tumor-bearing mice. We then assessed the effect of this localized radiotherapy on tumor growth and immunological function. The first protocol only slightly delayed tumor growth and was accompanied by a decrease in cytotoxic activity of the splenocytes. The second protocol enabled 50% of the tumor-bearing group to survive for more than 6 months. At the same time, there was no decrease in cytotoxic activity of the spleen even after the full course of nine irradiations. We assumed that the depressive effect of 700 rad was due to the scatter, and elicited a threshold dose of 12 to 15 rad from the dose-response studies in cytotoxicity

  4. Recognition of chemical compounds in contaminated water using time-dependent multiple dose cellular responses

    International Nuclear Information System (INIS)

    Highlights: ► Dose- and time-dependent cellular responses are used to evaluate the cytotoxicity. ► The CI can reflect the cell number, cell viability, morphological change, etc. ► The CSVID can capture the dynamic information after cells exposed to toxins. ► The multi-class classification can distinguish the compounds using multi-doses. ► The majority vote strategy (fingerprint) can improve the classification accuracy. - Abstract: An early determination of toxicant compounds of water contaminations can gain critical time to protect citizens’ health and save substantial amounts of medical costs. To determine toxins in real time, a multi-dose classification algorithm using cellular state variable identification (CSVID) is developed in this paper. First, the dynamic cytotoxicity response profiles of living cells are measured using a real-time cell electronic sensing (RT-CES) system. Changes in cell number expressed as cell index (CI) are recorded on-line as time series. Then CSVID, which reflects the cell killing, cell lysis and certain cellular pathological changes, is extracted from those dynamic cellular responses. Finally, a support vector machine (SVM) algorithm based on CSVID is employed to classify chemical compounds and determine their analogous cellular response pathway. In order to increase the classification accuracy, a majority vote of the class labels is also proposed. Several validation studies demonstrate that CSVID-based classification algorithm has great potential in distinguishing the cytotoxicity response of the cells in the presence of toxins.

  5. A germline polymorphism of thymine DNA glycosylase induces genomic instability and cellular transformation.

    Directory of Open Access Journals (Sweden)

    Ashley Sjolund

    2014-11-01

    Full Text Available Thymine DNA glycosylase (TDG functions in base excision repair, a DNA repair pathway that acts in a lesion-specific manner to correct individual damaged or altered bases. TDG preferentially catalyzes the removal of thymine and uracil paired with guanine, and is also active on 5-fluorouracil (5-FU paired with adenine or guanine. The rs4135113 single nucleotide polymorphism (SNP of TDG is found in 10% of the global population. This coding SNP results in the alteration of Gly199 to Ser. Gly199 is part of a loop responsible for stabilizing the flipped abasic nucleotide in the active site pocket. Biochemical analyses indicate that G199S exhibits tighter binding to both its substrate and abasic product. The persistent accumulation of abasic sites in cells expressing G199S leads to the induction of double-strand breaks (DSBs. Cells expressing the G199S variant also activate a DNA damage response. When expressed in cells, G199S induces genomic instability and cellular transformation. Together, these results suggest that individuals harboring the G199S variant may have increased risk for developing cancer.

  6. Oxidative stress-induced proteome alterations target different cellular pathways in human myoblasts

    DEFF Research Database (Denmark)

    Baraibar, Martin A; Hyzewicz, Janek; Rogowska-Wrzesinska, Adelina;

    2011-01-01

    Although increased oxidative stress has been associated with the impairment of proliferation and function of adult human muscle stem cells, proteins either involved in the stress response or damaged by oxidation have not been identified. A parallel proteomics approach was performed for analyzing...... are mainly cytosolic and involved in carbohydrate metabolism, cellular assembly, cellular homeostasis, and protein synthesis and degradation. Pathway analysis revealed skeletal and muscular disorders, cell death, and cancer-related as the main molecular networks altered. Interestingly, these pathways...

  7. Physicochemical determinants in the cellular responses to nanostructured amorphous silicas.

    Science.gov (United States)

    Gazzano, Elena; Ghiazza, Mara; Polimeni, Manuela; Bolis, Vera; Fenoglio, Ivana; Attanasio, Angelo; Mazzucco, Gianna; Fubini, Bice; Ghigo, Dario

    2012-07-01

    Amorphous silicas, opposite to crystalline polymorphs, have been regarded so far as nonpathogenic, but few studies have addressed the toxicity of the wide array of amorphous silica forms. With the advent of nanotoxicology, there has been a rising concern about the safety of silica nanoparticles to be used in nanomedicine. Here, we report a study on the toxicity of amorphous nanostructured silicas obtained with two different preparation procedures (pyrolysis vs. precipitation), the pyrogenic in two very different particle sizes, in order to assess the role of size and origin on surface properties and on the cell damage, oxidative stress, and inflammatory response elicited in murine alveolar macrophages. A quartz dust was employed as positive control and monodispersed silica spheres as negative control. Pyrogenic silicas were remarkably more active than the precipitated one as to cytotoxicity, reactive oxygen species production, lipid peroxidation, nitric oxide synthesis, and production of tumor necrosis factor-α, when compared both per mass and per unit surface. Between the two pyrogenic silicas, the larger one was the more active. Silanols density is the major difference in surface composition among the three silicas, being much larger than the precipitated one as indicated by joint calorimetric and infrared spectroscopy analysis. We assume here that full hydroxylation of a silica surface, with consequent stable coverage by water molecules, reduces/inhibits toxic behavior. The preparation route appears thus determinant in yielding potentially toxic materials, although the smallest size does not always correspond to an increased toxicity. PMID:22491428

  8. RRM2 induces NF-κB-dependent MMP-9 activation and enhances cellular invasiveness

    International Nuclear Information System (INIS)

    Ribonucleotide reductase is a dimeric enzyme that catalyzes conversion of ribonucleotide 5'-diphosphates to their 2'-deoxynucleotide forms, a rate-limiting step in the production of 2'-deoxyribonucleoside 5'-triphosphates required for DNA synthesis. The ribonucleotide reductase M2 subunit (RRM2) is a determinant of malignant cellular behavior in a range of human cancers. We examined the effect of RRM2 overexpression on pancreatic adenocarcinoma cellular invasiveness and nuclear factor-κB (NF-κB) transcription factor activity. RRM2 overexpression increases pancreatic adenocarcinoma cellular invasiveness and MMP-9 expression in a NF-κB-dependent manner. RNA interference (RNAi)-mediated silencing of RRM2 expression attenuates cellular invasiveness and NF-κB activity. NF-κB is a key mediator of the invasive phenotypic changes induced by RRM2 overexpression

  9. Opportunities for nutritional amelioration of radiation-induced cellular damage

    Science.gov (United States)

    Turner, Nancy D.; Braby, Leslie A.; Ford, John; Lupton, Joanne R.

    2002-01-01

    The closed environment and limited evasive capabilities inherent in space flight cause astronauts to be exposed to many potential harmful agents (chemical contaminants in the environment and cosmic radiation exposure). Current power systems used to achieve space flight are prohibitively expensive for supporting the weight requirements to fully shield astronauts from cosmic radiation. Therefore, radiation poses a major, currently unresolvable risk for astronauts, especially for long-duration space flights. The major detrimental radiation effects that are of primary concern for long-duration space flights are damage to the lens of the eye, damage to the immune system, damage to the central nervous system, and cancer. In addition to the direct damage to biological molecules in cells, radiation exposure induces oxidative damage. Many natural antioxidants, whether consumed before or after radiation exposure, are able to confer some level of radioprotection. In addition to achieving beneficial effects from long-known antioxidants such as vitamins E and C and folic acid, some protection is conferred by several recently discovered antioxidant molecules, such as flavonoids, epigallocatechin, and other polyphenols. Somewhat counterintuitive is the protection provided by diets containing elevated levels of omega-3 polyunsaturated fatty acids, considering they are thought to be prone to peroxidation. Even with the information we have at our disposal, it will be difficult to predict the types of dietary modifications that can best reduce the risk of radiation exposure to astronauts, those living on Earth, or those enduring diagnostic or therapeutic radiation exposure. Much more work must be done in humans, whether on Earth or, preferably, in space, before we are able to make concrete recommendations.

  10. Extracytoplasmic Stress Responses Induced by Antimicrobial Cationic Polyethylenimines

    OpenAIRE

    Lander, Blaine A.; Checchi, Kyle D.; Koplin, Stephen A.; Smith, Virginia F.; Domanski, Tammy L.; Isaac, Daniel D.; Lin, Shirley

    2012-01-01

    The ability of an antimicrobial, cationic polyethylenimine (PEI+) to induce the three known extracytoplasmic stress responses of Escherichia coli was quantified. Exposure of E. coli to PEI+ in solution revealed specific, concentration-dependent induction of the Cpx extracytoplasmic cellular stress response, ~2.0-2.5 fold at 320 μg/mL after 1.5 hours without significant induction of the σE or Bae stress responses. In comparison, exposure of E. coli to a non-antimicrobial polymer, polyethylene ...

  11. Cellular Adhesion Tripeptide RGD Inhibits Growth of Human Ileocecal Adenocarcinoma Cells HCT-8 and Induces Apoptosis

    Institute of Scientific and Technical Information of China (English)

    WANG Hua; ZENG Hong-bin; YANG Shao-juan; GAO Shen; HUANG Yi-bing; HOU Rui-zhen; ZHAO Mi-feng; XU Li; ZHANG Xue-zhong

    2007-01-01

    The tripeptide, Arg-Gly-Asp(RGD) motif is an integrin-recognition site found in adhesive proteins present in extracellular matrices(ECM) and in the blood. HCT-8 cells were treated with cellular adhesion tripeptide RGD at various concentrations. MTT assay was performed to examine the growth and proliferation of HCT-8 cells after treatment with RGD for 48 h. Haematoxylin and Eosin(HE) staining and electromicroscope were used to observe the morphology of apoptotic cells. Survivin and flow cytometry were also used to analyze the HCT-8 apoptosis. Cellular adhesion tripeptide RGD significantly inhibits the growth and proliferation of HCT-8 cells in a dose-dependent manner and induces apoptosis of HCT-8. These results indicate that cellular adhesion tripeptide RGD inhibits the growth and proliferation of tumor HCT-8 cell, probably by the aid of inducing apoptosis of HCT-8 cell.

  12. Cellular response to DNA damage. Link between p53 and DNA-PK

    International Nuclear Information System (INIS)

    Cells which lack DNA-activated protein kinase (DNA-PK) are very susceptible to ionizing radiation and display an inability to repair double-strand DNA breaks. DNA-PK is a member of a protein kinase family that includes ATR and ATM which have strong homology in their carboxy-terminal kinase domain with Pl-3 kinase. ATM has been proposed to act upstream of p53 in cellular response to ionizing radiation. DNA-PK may similarly interact with p53 in cellular growth control and in mediation of the response to ionizing radiation. (author)

  13. Region-Specific Diet-induced and Leptin-Induced Cellular Leptin Resistance Includes the Ventral Tegmental Area in Rats

    OpenAIRE

    Matheny, M.; Shapiro, A.; Tümer, N.; Scarpace, P. J.

    2010-01-01

    Diet-induced obesity (DIO) results in region-specific cellular leptin resistance in the arcuate nucleus (ARC) of the hypothalamus in one strain of mice and in several medial basal hypothalamic regions in another. We hypothesized that the ventral tegmental area (VTA) is also likely susceptible to diet-induced and leptin-induced leptin resistance in parallel to that in hypothalamic areas. We examined two forms of leptin resistance in F344xBN rats, that induced by 6-months of high fat (HF) feedi...

  14. 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; Nejsum, Peter; Thamsborg, Stig Milan; Roepstorff, Allan Knud; Iburg, Tine Moesgaard

    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 as.......001), 28 (P < 0.01) and 42 dpi (P < 0.05). A. galli infection induced changes in the mucosal thickness as reduced villi length at 7, 10, 14, 21 and 28 dpi and in the degree of general cellular infiltration in the lamina propria of the mucosal layer. No adult worms were seen during the experiment; therefore...

  15. 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

    -derived standardized uptake values were calculated for Achilles tendons and calf muscles and compared to gene expression and immunohistochemical evaluations of Ki67. RESULTS: Treadmill running induced increased uptake of FLT uptake in calf muscles (30%; p < 0.001) and in Achilles tendon (21%, p < 0.001). The image......-derived results were supported by a correlation in calf muscle to Ki67 (protein and mRNA level), while this coherence was not found in tendon. CONCLUSION: FLT-PET seems to be a promising tool for imaging of exercise-induced cellular proliferation in musculo-tendinous tissue.......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 (n...

  16. 应用含CpG基序的寡核苷酸增强乙型肝炎病毒基因疫苗诱导的细胞免疫应答%CpG oligodeoxyribonucleotide potently enhances cellular immune responses induced by hepatitis B virus gene vaccines

    Institute of Scientific and Technical Information of China (English)

    李文波; 姚志强; 周永兴; 冯志华

    2000-01-01

    Objective To investigate the effects of CpG oligodeoxyribonucleotide(ODN)as adju-vants on cellular immune responses in mice immunized with hepatitis B virus(HBV)gene vaccines.Meth-ods Recombinant eukaryotic expression plasmids of pCR3.1-S encoding S protein of HBV were construct-ed as gene vaccines.Phosphorothioate oligodeoxynueleotides containing one CpG motif were synthesized as adiuvants.Then Balb/c mice were inoculated so that the immune responses to HBV could be studied.Lym-phocyte proliferation reactions and cytotoxic T lymphocyte activities were detected through3 H-TdR incor-potation and 4-hour 51Cr release assays. Results Compared with plasmid vectors of pCR3.1,HBV gene vaccines could induce strong lymphocyte proliferation reactions and cytotoxic T lymphocyte activities in im-munized mice(P<0.05).Immunized mice with CpG ODN showed higher specific cellular responses to HBV than those without CpG 0DN(P<0.05). Conclusion CpG ODN can act as adjuvants to enhence cellular immune responses in mice immunized with HBV gene vaccines.%目的 探讨人工合成的含CpG基序的寡核苷酸(ODN)作为佐剂对乙型肝炎病毒(HBV)基因疫苗诱导小鼠产生细胞免疫应答的影响.方法 构建编码HBV表面抗原蛋白S的重组真核表达质粒pCR3.1-S作为HBV基因疫苗,人工合成含CpG基序(motif)的硫代磷酸寡核苷酸作为佐剂,以Balb/c小鼠作为实验动物进行免疫接种;采用3H-TdR法、51Cr 4 h释放法等分别检测免疫小鼠的淋巴细胞增殖和杀伤功能.结果 与空载体对照组相比较,HBV基因疫苗诱发Balb/c小鼠产生较好的HBV特异的淋巴细胞增殖及杀伤效应(P<0.05);应用CpG ODN组与未应用组相比较,免疫小鼠产生更强的HBV特异性细胞免疫应答(P<0.05).结论 CpG ODN作为佐剂可增强HBV基因疫苗诱导Balb/c小鼠产生细胞免疫应答.

  17. CYCLOPHOSPHAMIDE TERATOGENESIS: EVIDENCE FOR COMPENSATORY RESPONSES TO INDUCED CELLULAR TOXICITY

    Science.gov (United States)

    Cyclophosphamide (CP) administered ip to pregnant mice on day 10 og gestation causes severe malformations at 20 mg/kg and is embryolethal at higher doses. n the present study, CP was administered at 1, 5, 10 or 20 mg/kg. mbryos were removed at 8 and 28 hrs post dosing for immedia...

  18. EICOSANOIDS MEDIATE MANDUCA SEXTA CELLULAR RESPONSE TO BEAUVERIA BASSIANA: A ROLE FOR THE LIPOXYGENASE PATHWAY

    Science.gov (United States)

    Many studies have documented the involvement of eicosanoids in insect cellular immune responses to bacteria. The use of Beauveria bassiana as a nodulation elicitor, with inhibition of phospholipase A2 by dexamethasone extends the principal to fungi. This study also provides the first evidence of i...

  19. Induction of stress responses by polluting agents which dis-regulate cellular homeostasis

    International Nuclear Information System (INIS)

    There is growing concern both in the scientific community and among the general public about the effects of exposure to low levels of radiation and environmental chemicals. The increased incidence of cancer, reproduction disorders and allergies have been associated with ambient environmental exposure to these pollutants. The pollution burden is generally made up of a mixture of agents, occurring at concentrations of the individual compounds which are not considered harmful and which are below the action level. Individual pollutants can act through a variety of primary toxicity mechanisms. However the resulting secondary and tertiary toxicity mechanisms which affect cellular homeostasis might be more common. These resulting stress responses, including oxidative stress, have been associated with effects that include increased level of death during cell division, increased levels of mutation and increased tolerance of mutations in cell populations, increased levels of cytogenetic abnormalities and many other symptoms. These effects are linked to a persistent increase in (oxidative) stress and are particularly evident in the haematopoietic system (possibly due to the high rate self of renewal in that system). Therefore prolonged exposure to mixtures of chemicals and radiation might result in additive and synergistic stress responses which can induce long-term delayed effects, often in progeny or in cells not directly exposed to the agent/s. The existence of a common (oxidative) stress mechanism means that the effects of individual pollutants may not be considered in isolation. Rather the total pollution burden may need to be measured using a response rather than a dose based scoring or ranking system. Improved understanding of toxicity mechanisms and effects underpins improved risk assessment and identification of biomarkers. The immune system plays a pivotal role in maintaining health status, and disruption of immune functions can lead to increased susceptibility to

  20. Embryonic exposure to lead: comparison of immune and cellular responses in unchallenged and virally stressed chickens

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji-Eun; Kao, Elizabeth; Dietert, Rodney R. [Institute for Comparative and Environmental Toxicology, College of Veterinary Medicine, Cornell University, Ithaca, NY (United States); Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (United States); Naqi, Syed A. [Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY (United States)

    2002-01-01

    Lead, a ubiquitous environmental contaminant, has been shown to modulate various functions of the immune system and decrease host resistance to infectious disease. However, limited information is available concerning the direct effects of lead on the host immune response to an infectious agent after developmental exposure. The current study utilized chickens to examine the effect of embryonic lead exposure on immune and cellular responses during viral challenge. Sublethal doses of lead were introduced into fertilized Cornell K Strain White Leghorn chicken eggs via the air sac at day 5 or day 12 of embryonic development (designated as E5 and E12, respectively). Four-week-old female chickens were inoculated with infectious bronchitis virus (IBV) strain M41. Antibody titer to IBV, delayed-type hypersensitivity (DTH) response against bovine serum albumin (BSA), the absolute number and percentage of leukocyte subpopulations, and interferon-{gamma} (IFN-{gamma})-like cytokine production by splenocytes were evaluated at 5-6 weeks of age. While antibody response to IBV in juvenile chicks was unaffected by the in ovo lead exposure, IFN-{gamma}-like cytokine production by splenocytes was significantly depressed following lead exposure at both developmental stages. In contrast with this pattern, the DTH response against BSA was unaffected following E5 exposure, but was significantly decreased after E12 exposure to lead. These changes were similar to those previously reported in chickens not exposed to IBV. While lead exposure at E5 induced significant changes in the percentage of circulating heterophils at 1 day postinfection (dpi), lead did not cause any change in relative leukocyte counts after E12 exposure. At 7 dpi, E5 lead exposure resulted in decreased absolute number and percentage of circulating lymphocytes, while total leukocyte counts, and the absolute number and percentage of circulating monocytes and heterophils were significantly reduced in E12 lead

  1. SEX DIFFERENCES AND ESTROGEN MODULATION OF THE CELLULAR IMMUNE RESPONSE AFTER INJURY

    OpenAIRE

    Bird, Melanie D.; Karavitis, John; Kovacs, Elizabeth J

    2008-01-01

    Cell-mediated immunity is extremely important for resolution of infection and for proper healing from injury. However, the cellular immune response is dysregulated following injuries such as burn and hemorrhage. Sex hormones are known to regulate immunity, and a well-documented dichotomy exists in the immune response to injury between the sexes. This disparity is caused by differences in immune cell activation, infiltration, and cytokine production during and after injury. Estrogen and testos...

  2. Cellular Levels of Oxidative Stress Affect the Response of Cervical Cancer Cells to Chemotherapeutic Agents

    OpenAIRE

    Maria Filippova; Valery Filippov; Williams, Vonetta M; Kangling Zhang; Anatolii Kokoza; Svetlana Bashkirova; Penelope Duerksen-Hughes

    2014-01-01

    Treatment of advanced and relapsed cervical cancer is frequently ineffective, due in large part to chemoresistance. To examine the pathways responsible, we employed the cervical carcinoma-derived SiHa and CaSki cells as cellular models of resistance and sensitivity, respectively, to treatment with chemotherapeutic agents, doxorubicin, and cisplatin. We compared the proteomic profiles of SiHa and CaSki cells and identified pathways with the potential to contribute to the differential response....

  3. Gestational Zinc Deficiency Impairs Humoral and Cellular Immune Responses to Hepatitis B Vaccination in Offspring Mice

    OpenAIRE

    Ning Zhao; Xuelian Wang; Ying Zhang; Qiuhong Gu; Fen Huang; Wei Zheng; Zhiwei Li

    2013-01-01

    BACKGROUND: Gestational zinc deficiency has been confirmed to impair the infant immune function. However, knowledge about effects of maternal mild zinc deficiency during pregnancy on hepatitis B vaccine responsiveness in offspring is limited. In this report, we aimed to examine how maternal zinc deficiency during pregnancy influences humoral and cellular immune responses to hepatitis B vaccination in offspring of BALB/c mice. METHODOLOGY/PRINCIPAL FINDINGS: From day 1 of pregnancy upon delive...

  4. Cellular Responses during Morphological Transformation in Azospirillum brasilense and Its flcA Knockout Mutant

    OpenAIRE

    Hou, Xingsheng; McMillan, Mary; Joëlle V. F. Coumans; 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 to...

  5. Sirtuin 7 promotes cellular survival following genomic stress by attenuation of DNA damage, SAPK activation and p53 response

    International Nuclear Information System (INIS)

    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

  6. 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

  7. Recognition of chemical compounds in contaminated water using time-dependent multiple dose cellular responses

    Energy Technology Data Exchange (ETDEWEB)

    Pan, T.H., E-mail: thpan@ujs.edu.cn [School of Electrical and Information Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013 (China); Department of Chemical and Material Engineering, University of Alberta, Edmonton, Alberta T6G 2G6 (Canada); Huang, B., E-mail: biao.huang@ualberta.ca [Department of Chemical and Material Engineering, University of Alberta, Edmonton, Alberta T6G 2G6 (Canada); Xing, J.Z., E-mail: jzxing@ualberta.ca [Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta T6G 2S2 (Canada); Zhang, W.P., E-mail: weiping.zhang@gov.ab.ca [Alberta Health and Wellness, Edmonton, Alberta T5J 1S6 (Canada); Gabos, S., E-mail: stephan.gabos@gov.ab.ca [Alberta Health and Wellness, Edmonton, Alberta T5J 1S6 (Canada); Chen, J., E-mail: jchen@ece.ualberta.ca [Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta T6G 2S2 (Canada)

    2012-04-29

    Highlights: Black-Right-Pointing-Pointer Dose- and time-dependent cellular responses are used to evaluate the cytotoxicity. Black-Right-Pointing-Pointer The CI can reflect the cell number, cell viability, morphological change, etc. Black-Right-Pointing-Pointer The CSVID can capture the dynamic information after cells exposed to toxins. Black-Right-Pointing-Pointer The multi-class classification can distinguish the compounds using multi-doses. Black-Right-Pointing-Pointer The majority vote strategy (fingerprint) can improve the classification accuracy. - Abstract: An early determination of toxicant compounds of water contaminations can gain critical time to protect citizens' health and save substantial amounts of medical costs. To determine toxins in real time, a multi-dose classification algorithm using cellular state variable identification (CSVID) is developed in this paper. First, the dynamic cytotoxicity response profiles of living cells are measured using a real-time cell electronic sensing (RT-CES) system. Changes in cell number expressed as cell index (CI) are recorded on-line as time series. Then CSVID, which reflects the cell killing, cell lysis and certain cellular pathological changes, is extracted from those dynamic cellular responses. Finally, a support vector machine (SVM) algorithm based on CSVID is employed to classify chemical compounds and determine their analogous cellular response pathway. In order to increase the classification accuracy, a majority vote of the class labels is also proposed. Several validation studies demonstrate that CSVID-based classification algorithm has great potential in distinguishing the cytotoxicity response of the cells in the presence of toxins.

  8. Novel Adenovirus type 5 vaccine platform induces cellular immunity against HIV-1 Gag, Pol, Nef despite the presence of Ad5 immunity

    OpenAIRE

    Gabitzsch, Elizabeth S; Xu, Younong; Yoshida, Lois H.; Balint, Joseph; Amalfitano, Andrea; Jones, Frank R.

    2009-01-01

    Recombinant Adenovirus serotype 5 (Ad5) vectors have been used as vaccine platforms in numerous animal and human clinical studies. The immune response induced by Ad5 vaccines can be mitigated due to pre-existing Ad5 immunity. We report here the use of a novel Ad5 platform to induce cellular immune responses (CMI) in Ad5 hyper immunized mice. The effectiveness of the Ad5 [E1−, E2b−] vaccine platform was evaluated using HIV-1 Gag, Pol, and Nef as antigenic transgenes. Broad CMI was induced foll...

  9. A magnetically actuated cellular strain assessment tool for quantitative analysis of strain induced cellular reorientation and actin alignment

    Science.gov (United States)

    Khademolhosseini, F.; Liu, C.-C.; Lim, C. J.; Chiao, M.

    2016-08-01

    Commercially available cell strain tools, such as pneumatically actuated elastomer substrates, require special culture plates, pumps, and incubator setups. In this work, we present a magnetically actuated cellular strain assessment tool (MACSAT) that can be implemented using off-the-shelf components and conventional incubators. We determine the strain field on the MACSAT elastomer substrate using numerical models and experimental measurements and show that a specific region of the elastomer substrate undergoes a quasi-uniaxial 2D stretch, and that cells confined to this region of the MACSAT elastomer substrate undergo tensile, compressive, or zero axial strain depending on their angle of orientation. Using the MACSAT to apply cyclic strain on endothelial cells, we demonstrate that actin filaments within the cells reorient away from the stretching direction, towards the directions of minimum axial strain. We show that the final actin orientation angles in strained cells are spread over a region of compressive axial strain, confirming previous findings on the existence of a varied pre-tension in the actin filaments of the cytoskeleton. We also demonstrate that strained cells exhibit distinctly different values of actin alignment coherency compared to unstrained cells and therefore propose that this parameter, i.e., the coherency of actin alignment, can be used as a new readout to determine the occurrence/extent of actin alignment in cell strain experiments. The tools and methods demonstrated in this study are simple and accessible and can be easily replicated by other researchers to study the strain response of other adherent cells.

  10. Cell damage from radiation-induced bystander effects for different cell densities simulated by a mathematical model via cellular automata

    Energy Technology Data Exchange (ETDEWEB)

    Meireles, Sincler P. de; Santos, Adriano M.; Grynberg, Suely Epsztein, E-mail: spm@cdtn.b, E-mail: amsantos@cdtn.b, E-mail: seg@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Nunes, Maria Eugenia S., E-mail: mariaeugenia@iceb.ufop.b [Universidade Federal de Ouro Preto (UFOP), MG (Brazil)

    2011-07-01

    During recent years, there has been a shift from an approach focused entirely on DNA as the main target of ionizing radiation to a vision that considers complex signaling pathways in cells and among cells within tissues. Several newly recognized responses were classified as the so-called non-target responses in which the biological effects are not directly related to the amount of energy deposited in the DNA of cells that were traversed by radiation. In 1992 the bystander effect was described referring to a series of responses such as death, chromosomal instability or other abnormalities that occur in non-irradiated cells that came into contact with irradiated cells or medium from irradiated cells. In this work, we have developed a mathematical model via cellular automata, to quantify cell death induced by the bystander effect. The model is based on experiments with irradiated cells conditioned medium which suggests that irradiated cells secrete molecules in the medium that are capable of damaging other cells. The computational model consists of two-dimensional cellular automata which is able to simulate the transmission of bystander signals via extrinsic route and via Gap junctions. The model has been validated by experimental results in the literature. The time evolution of the effect and the dose-response curves were obtained in good accordance to them. Simulations were conducted for different values of bystander and irradiated cell densities with constant dose. From this work, we have obtained a relationship between cell density and effect. (author)

  11. Cell damage from radiation-induced bystander effects for different cell densities simulated by a mathematical model via cellular automata

    International Nuclear Information System (INIS)

    During recent years, there has been a shift from an approach focused entirely on DNA as the main target of ionizing radiation to a vision that considers complex signaling pathways in cells and among cells within tissues. Several newly recognized responses were classified as the so-called non-target responses in which the biological effects are not directly related to the amount of energy deposited in the DNA of cells that were traversed by radiation. In 1992 the bystander effect was described referring to a series of responses such as death, chromosomal instability or other abnormalities that occur in non-irradiated cells that came into contact with irradiated cells or medium from irradiated cells. In this work, we have developed a mathematical model via cellular automata, to quantify cell death induced by the bystander effect. The model is based on experiments with irradiated cells conditioned medium which suggests that irradiated cells secrete molecules in the medium that are capable of damaging other cells. The computational model consists of two-dimensional cellular automata which is able to simulate the transmission of bystander signals via extrinsic route and via Gap junctions. The model has been validated by experimental results in the literature. The time evolution of the effect and the dose-response curves were obtained in good accordance to them. Simulations were conducted for different values of bystander and irradiated cell densities with constant dose. From this work, we have obtained a relationship between cell density and effect. (author)

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

    Directory of Open Access Journals (Sweden)

    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

  13. 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

  14. In vitro cellular response to hydroxyapatite scaffolds with oriented pore architectures

    International Nuclear Information System (INIS)

    The objective of the present work was to evaluate the in vitro cellular response to hydroxyapatite (HA) scaffolds with oriented pore architectures. Hydroxyapatite scaffolds with approximately the same porosity (65-70%) but two different oriented microstructures, described as 'columnar' (pore diameter = 90-110 μm) and 'lamellar' (pore width = 20-30 μm), were prepared by unidirectional freezing of suspensions. The response of murine MLO-A5 cells, an osteogenic cell line, to these scaffolds was evaluated using assays of MTT hydrolysis, alkaline phosphatase (ALP) activity, and alizarin red staining. While the cellular response to both groups of scaffolds was better than control wells, the columnar scaffolds with the larger pore width provided the most favorable substrate for cell proliferation and function. These results indicate that HA scaffolds with the columnar microstructure could be used for bone repair applications in vivo.

  15. Cellular and molecular response to irradiation in ataxia telangiectasia and in Fanconi's anemia

    International Nuclear Information System (INIS)

    Ataxia telangiectasia (AT) and Fanconi anemia (FA) are recessive genetic diseases featuring chromosomal instability, increased predisposition to cancer and in vitro hypersensitivity to ionizing radiation (AT) or DNA cross-linking agents (FA). Moreover, an in vivo hypersensitivity to γ-rays exposure was reported in both syndromes. Cellular response to irradiation includes growth arrest (cell cycle modification) and cell death (by apoptosis or necrosis). Since it is generally accepted that apoptosis modulates cellular sensitivity to genotoxic stress, it was of interest to investigate the contribution of apoptosis in determining FA and AT responses to DNA Damaging Agents. The results support the contention that the in vivo hypersensitivity to radiation in these syndromes is not related to a higher rate of apoptotic cells but could be to a higher necrotic response triggering inflammatory reactions in the patients affected by this syndromes. (authors)

  16. Submicron and nano formulations of titanium dioxide and zinc oxide stimulate unique cellular toxicological responses in the green microalga Chlamydomonas reinhardtii

    International Nuclear Information System (INIS)

    Highlights: • Uptake of TiO2 solids by C. reinhardtii generates ROS as an early stress response. • Submicron and nanoTiO2 exhibit benign effect on cell proliferation. • Uptake of ZnO solids and leached zinc by C. reinhardtii inhibit the alga growth. • No cellular oxidative stress is detected with submicron and nano ZnO exposure. • The toxicity of particles is not necessarily mediated by cellular oxidative stress. -- Abstract: The work investigates the eco-cytoxicity of submicron and nano TiO2 and ZnO, arising from the unique interactions of freshwater microalga Chlamydomonas reinhardtii to soluble and undissolved components of the metal oxides. In a freshwater medium, submicron and nano TiO2 exist as suspended aggregates with no-observable leaching. Submicron and nano ZnO undergo comparable concentration-dependent fractional leaching, and exist as dissolved zinc and aggregates of undissolved ZnO. Cellular internalisation of solid TiO2 stimulates cellular ROS generation as an early stress response. The cellular redox imbalance was observed for both submicron and nano TiO2 exposure, despite exhibiting benign effects on the alga proliferation (8-day EC50 > 100 mg TiO2/L). Parallel exposure of C. reinhardtii to submicron and nano ZnO saw cellular uptake of both the leached zinc and solid ZnO and resulting in inhibition of the alga growth (8-day EC50 ≥ 0.01 mg ZnO/L). Despite the sensitivity, no zinc-induced cellular ROS generation was detected, even at 100 mg ZnO/L exposure. Taken together, the observations confront the generally accepted paradigm of cellular oxidative stress-mediated cytotoxicity of particles. The knowledge of speciation of particles and the corresponding stimulation of unique cellular responses and cytotoxicity is vital for assessment of the environmental implications of these materials

  17. Submicron and nano formulations of titanium dioxide and zinc oxide stimulate unique cellular toxicological responses in the green microalga Chlamydomonas reinhardtii

    Energy Technology Data Exchange (ETDEWEB)

    Gunawan, Cindy, E-mail: c.gunawan@unsw.edu.au [ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Engineering, The University of New South Wales, Sydney, NSW (Australia); Sirimanoonphan, Aunchisa [ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Engineering, The University of New South Wales, Sydney, NSW (Australia); Teoh, Wey Yang [Clean Energy and Nanotechnology (CLEAN) Laboratory, School of Energy and Environment, City University of Hong Kong, Kowloon, Hong Kong Special Administrative Region (Hong Kong); Marquis, Christopher P., E-mail: c.marquis@unsw.edu.au [School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW (Australia); Amal, Rose [ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Engineering, The University of New South Wales, Sydney, NSW (Australia)

    2013-09-15

    Highlights: • Uptake of TiO{sub 2} solids by C. reinhardtii generates ROS as an early stress response. • Submicron and nanoTiO{sub 2} exhibit benign effect on cell proliferation. • Uptake of ZnO solids and leached zinc by C. reinhardtii inhibit the alga growth. • No cellular oxidative stress is detected with submicron and nano ZnO exposure. • The toxicity of particles is not necessarily mediated by cellular oxidative stress. -- Abstract: The work investigates the eco-cytoxicity of submicron and nano TiO{sub 2} and ZnO, arising from the unique interactions of freshwater microalga Chlamydomonas reinhardtii to soluble and undissolved components of the metal oxides. In a freshwater medium, submicron and nano TiO{sub 2} exist as suspended aggregates with no-observable leaching. Submicron and nano ZnO undergo comparable concentration-dependent fractional leaching, and exist as dissolved zinc and aggregates of undissolved ZnO. Cellular internalisation of solid TiO{sub 2} stimulates cellular ROS generation as an early stress response. The cellular redox imbalance was observed for both submicron and nano TiO{sub 2} exposure, despite exhibiting benign effects on the alga proliferation (8-day EC50 > 100 mg TiO{sub 2}/L). Parallel exposure of C. reinhardtii to submicron and nano ZnO saw cellular uptake of both the leached zinc and solid ZnO and resulting in inhibition of the alga growth (8-day EC50 ≥ 0.01 mg ZnO/L). Despite the sensitivity, no zinc-induced cellular ROS generation was detected, even at 100 mg ZnO/L exposure. Taken together, the observations confront the generally accepted paradigm of cellular oxidative stress-mediated cytotoxicity of particles. The knowledge of speciation of particles and the corresponding stimulation of unique cellular responses and cytotoxicity is vital for assessment of the environmental implications of these materials.

  18. Rhizobacterial Strain Bacillus megaterium BOFC15 Induces Cellular Polyamine Changes that Improve Plant Growth and Drought Resistance

    Science.gov (United States)

    Zhou, Cheng; Ma, Zhongyou; Zhu, Lin; Xiao, Xin; Xie, Yue; Zhu, Jian; Wang, Jianfei

    2016-01-01

    Plant-growth-promoting rhizobacteria can improve plant growth, development, and stress adaptation. However, the underlying mechanisms are still largely unclear. We investigated the effects of Bacillus megaterium BOFC15 on Arabidopsis plants. BOFC15 produced and secreted spermidine (Spd), a type of polyamine (PA) that plays an important role in plant growth. Moreover, BOFC15 induced changes in the cellular PAs of plants that promoted an increase of free Spd and spermine levels. However, these effects were remarkably abolished by the addition of dicyclohexylamine (DCHA), a Spd biosynthetic inhibitor. Additionally, the inoculation with BOFC15 remarkably increased plant biomass, improved root system architecture, and augmented photosynthetic capacity. Inoculated plants also displayed stronger ability to tolerate drought stress than non-inoculated (control) plants. Abscisic acid (ABA) content was notably higher in the inoculated plants than in the control plants under drought stress and polyethylene glycol (PEG)-induced stress conditions. However, the BOFC15-induced ABA synthesis was markedly inhibited by DCHA. Thus, microbial Spd participated in the modulation of the ABA levels. The Spd-producing BOFC15 improved plant drought tolerance, which was associated with altered cellular ABA levels and activated adaptive responses. PMID:27338359

  19. Agonistic encounters and cellular angst: social interactions induce heat shock proteins in juvenile salmonid fish

    OpenAIRE

    Currie, Suzanne; LeBlanc, Sacha; Watters, M. Alexandrea; Gilmour, Kathleen M.

    2009-01-01

    Juvenile salmonid fish readily form dominance hierarchies when faced with limited resources. While these social interactions may result in profound behavioural and physiological stress, it is unknown if this social stress is evident at the level of the cellular stress response—specifically, the induction of stress or heat shock proteins (Hsps). Thus, the goal of our study was to determine if Hsps are induced during hierarchy formation in juvenile rainbow trout (Oncorhynchus mykiss). To this e...

  20. Cell fusion induced by ERVWE1 or measles virus causes cellular senescence

    OpenAIRE

    Chuprin, Anna; Gal, Hilah; BIRON-SHENTAL, Tal; Biran, Anat; Amiel, Aliza; Rozenblatt, Shmuel; Krizhanovsky, Valery

    2013-01-01

    Cellular senescence limits proliferation of potentially detrimental cells, preventing tumorigenesis and restricting tissue damage. However, the function of senescence in nonpathological conditions is unknown. Here, Krizhanovsky and colleagues discover a new pathway to activate senescence cell fusion. The authors find that fusion-induced senescence occurs during embryonic development in the placenta. A counterpart of this process is also observed after infection by the measles virus. The resul...

  1. 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

  2. A signature microRNA expression profile for the cellular response to thermal stress

    Science.gov (United States)

    Wilmink, Gerald J.; Roth, Caleb C.; Ketchum, Norma; Ibey, Bennett L.; Waterworth, Angela; Suarez, Maria; Roach, William P.

    2009-02-01

    Recently, an extensive layer of intra-cellular signals was discovered that was previously undetected by genetic radar. It is now known that this layer consists primarily of a class of short noncoding RNA species that are referred to as microRNAs (miRNAs). MiRNAs regulate protein synthesis at the post-transcriptional level, and studies have shown that they are involved in many fundamental cellular processes. In this study, we hypothesized that miRNAs may be involved in cellular stress response mechanisms, and that cells exposed to thermal stress may exhibit a signature miRNA expression profile indicative of their functional involvement in such mechanisms. To test our hypothesis, human dermal fibroblasts were exposed to an established hyperthermic protocol, and the ensuing miRNA expression levels were evaluated 4 hr post-exposure using microRNA microarray gene chips. The microarray data shows that 123 miRNAs were differentially expressed in cells exposed to thermal stress. We collectively refer to these miRNAs as thermalregulated microRNAs (TRMs). Since miRNA research is in its infancy, it is interesting to note that only 27 of the 123 TRMs are currently annotated in the Sanger miRNA registry. Prior to publication, we plan to submit the remaining novel 96 miRNA gene sequences for proper naming. Computational and thermodynamic modeling algorithms were employed to identify putative mRNA targets for the TRMs, and these studies predict that TRMs regulate the mRNA expression of various proteins that are involved in the cellular stress response. Future empirical studies will be conducted to validate these theoretical predictions, and to further examine the specific role that TRMs play in the cellular stress response.

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

    International Nuclear Information System (INIS)

    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 TiO2 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 (NH4)2O·5B2O3, (NH4)2SO4, or (NH4)3PO4, 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 (TiO2), while incorporation from electrolyte was only observed for (NH4)3PO4. 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 TiO2 formation. Overall, electrolyte selection showed no effect on either surface chemistry or cellular response of Ti materials

  4. 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.

  5. Activity against Mycobacterium tuberculosis with concomitant induction of cellular immune responses by a tetraaza-macrocycle with acetate pendant arms.

    Science.gov (United States)

    David, S; Ordway, D; Arroz, M J; Costa, J; Delgado, R

    2001-01-01

    The novel tetraaza-macrocyclic compound 3,7,11-tris(carboxymethyl)-3,7,11,17-tetraaza-bicyclo[11.3.1]heptadeca-1(17),13,15-triene, abbreviated as ac3py14, was investigated for its activity against Mycobacterium tuberculosis and for induction of protective cellular immune responses. Perspective results show that ac3py14 and its Fe3+ 1:1 complex, [Fe(ac3py14)], inhibited radiometric growth of several strains of M. tuberculosis. Inhibition with 25 microg/mL varied from 99% for H37Rv to 80% and above for multiple drug-resistant clinical isolates. The capacity of ac3py14 to elicit a beneficial immune response without cellular apoptosis was assessed and compared to the effects of virulent M. tuberculosis. The present study produces evidence that after stimulation with ac3py14 there was significant production of interferon gamma (IFN-gamma), whereas the production of interleukin-5 (IL-5) remained low, and there was development of a memory population (CD45RO). The level of binding of Annexin V, a marker of apoptosis, was not sufficient to result in toxic effects toward alphabeta and gammadelta T cells and CD14+ macrophages. This preliminary study is the first report of a compound that simultaneously exerts an inhibitory effect against M. tuberculosis and induces factors associated with protective immune responses. PMID:11501675

  6. Skeletal muscle plasticity: cellular and molecular responses to altered physical activity paradigms

    Science.gov (United States)

    Baldwin, Kenneth M.; Haddad, Fadia

    2002-01-01

    The goal of this article is to examine our current understanding of the chain of events known to be involved in the adaptive process whereby specific genes and their protein products undergo altered expression; specifically, skeletal muscle adaptation in response to altered loading states will be discussed, with a special focus on the regulation of the contractile protein, myosin heavy chain gene expression. This protein, which is both an important structural and regulatory protein comprising the contractile apparatus, can be expressed as different isoforms, thereby having an impact on the functional diversity of the muscle. Because the regulation of the myosin gene family is under the control of a complex set of processes including, but not limited to, activity, hormonal, and metabolic factors, this protein will serve as a cellular "marker" for studies of muscle plasticity in response to various mechanical perturbations in which the quantity and type of myosin isoform, along with other important cellular proteins, are altered in expression.

  7. Cellular and molecular players in adipose tissue inflammation in the development of obesity-induced insulin resistance.

    Science.gov (United States)

    Lee, Byung-Cheol; Lee, Jongsoon

    2014-03-01

    There is increasing evidence showing that inflammation is an important pathogenic mediator of the development of obesity-induced insulin resistance. It is now generally accepted that tissue-resident immune cells play a major role in the regulation of this obesity-induced inflammation. The roles that adipose tissue (AT)-resident immune cells play have been particularly extensively studied. AT contains most types of immune cells and obesity increases their numbers and activation levels, particularly in AT macrophages (ATMs). Other pro-inflammatory cells found in AT include neutrophils, Th1 CD4 T cells, CD8 T cells, B cells, DCs, and mast cells. However, AT also contains anti-inflammatory cells that counter the pro-inflammatory immune cells that are responsible for the obesity-induced inflammation in this tissue. These anti-inflammatory cells include regulatory CD4 T cells (Tregs), Th2 CD4 T cells, and eosinophils. Hence, AT inflammation is shaped by the regulation of pro- and anti-inflammatory immune cell homeostasis, and obesity skews this balance towards a more pro-inflammatory status. Recent genetic studies revealed several molecules that participate in the development of obesity-induced inflammation and insulin resistance. In this review, the cellular and molecular players that participate in the regulation of obesity-induced inflammation and insulin resistance are discussed, with particular attention being placed on the roles of the cellular players in these pathogeneses. This article is part of a Special Issue entitled: Modulation of Adipose Tissue in Health and Disease. PMID:23707515

  8. Phenyl 2-pyridyl ketoxime induces cellular senescence-like alterations via nitric oxide production in human diploid fibroblasts.

    Science.gov (United States)

    Yang, Kyeong Eun; Jang, Hyun-Jin; Hwang, In-Hu; Chung, Young-Ho; Choi, Jong-Soon; Lee, Tae-Hoon; Chung, Yun-Jo; Lee, Min-Seung; Lee, Mi Young; Yeo, Eui-Ju; Jang, Ik-Soon

    2016-04-01

    Phenyl-2-pyridyl ketoxime (PPKO) was found to be one of the small molecules enriched in the extracellular matrix of near-senescent human diploid fibroblasts (HDFs). Treatment of young HDFs with PPKO reduced the viability of young HDFs in a dose- and time-dependent manner and resulted in senescence-associated β-galactosidase (SA-β-gal) staining and G2/M cell cycle arrest. In addition, the levels of some senescence-associated proteins, such as phosphorylated ERK1/2, caveolin-1, p53, p16(ink4a) , and p21(waf1) , were elevated in PPKO-treated cells. To monitor the effect of PPKO on cell stress responses, reactive oxygen species (ROS) production was examined by flow cytometry. After PPKO treatment, ROS levels transiently increased at 30 min but then returned to baseline at 60 min. The levels of some antioxidant enzymes, such as catalase, peroxiredoxin II and glutathione peroxidase I, were transiently induced by PPKO treatment. SOD II levels increased gradually, whereas the SOD I and III levels were biphasic during the experimental periods after PPKO treatment. Cellular senescence induced by PPKO was suppressed by chemical antioxidants, such as N-acetylcysteine, 2,2,6,6-tetramethylpiperidinyloxy, and L-buthionine-(S,R)-sulfoximine. Furthermore, PPKO increased nitric oxide (NO) production via inducible NO synthase (iNOS) in HDFs. In the presence of NOS inhibitors, such as L-NG-nitroarginine methyl ester and L-NG-monomethylarginine, PPKO-induced transient NO production and SA-β-gal staining were abrogated. Taken together, these results suggest that PPKO induces cellular senescence in association with transient ROS and NO production and the subsequent induction of senescence-associated proteins. PMID:26696133

  9. 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...

  10. Humoral and Cellular Immune Responses to Yersinia pestis Infection in Long-Term Recovered Plague Patients

    OpenAIRE

    Li, Bei; Du, Chunhong; Zhou, Lei; Bi, Yujing; Wang, Xiaoyi; Wen, Li; Guo, Zhaobiao; Song, Zhizhong; Yang, Ruifu

    2012-01-01

    Plague is one of the most dangerous diseases and is caused by Yersinia pestis. Effective vaccine development requires understanding of immune protective mechanisms against the bacterium in humans. In this study, the humoral and memory cellular immune responses in plague patients (n = 65) recovered from Y. pestis infection during the past 16 years were investigated using a protein microarray and an enzyme-linked immunosorbent spot assay (ELISpot). The seroprevalence to the F1 antigen in all re...

  11. Independence of Measles-Specific Humoral and Cellular Immune Responses to Vaccination

    OpenAIRE

    Jacobson, Robert M.; Ovsyannikova, Inna G.; Vierkant, Robert A.; Pankratz, V. Shane; Poland, Gregory A.

    2012-01-01

    With a larger, independent cohort and more sophisticated measures, we sought to confirm our work that indicated independence of humoral and cellular immunity following measles vaccination. We recruited an age-stratified random cohort of 764 healthy subjects from all socio-economic strata, all with medical-record documentation of two age-appropriate doses of measles-containing vaccine. We quantified measles-specific neutralizing antibody levels and assayed the IFN-γ ELISPOT response to measles...

  12. 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. PMID:21118962

  13. Mitochondrial dysfunction induced by frataxin deficiency is associated with cellular senescence and abnormal calcium metabolism

    Directory of Open Access Journals (Sweden)

    Francesc Palau

    2014-05-01

    Full Text Available Friedreich ataxia is considered a neurodegenerative disorder involving both the peripheral and central nervous systems. Dorsal root ganglia (DRG are the major target tissue structures. This neuropathy is caused by mutations in the FXN gene that encodes frataxin. Here, we investigated the mitochondrial and cell consequences of frataxin depletion in a cellular model based on frataxin silencing in SH-SY5Y human neuroblastoma cells, a cell line that has been used widely as in vitro models for studies on neurological diseases. We showed that the reduction of frataxin induced mitochondrial dysfunction due to a bioenergetic deficit and abnormal Ca2+ homeostasis in the mitochondria that were associated with oxidative and endoplasmic reticulum stresses. The depletion of frataxin did not cause cell death but increased autophagy, which may have a cytoprotective effect against cellular insults such as oxidative stress. Frataxin silencing provoked slow cell growth associated with cellular senescence, as demonstrated by increased SA-βgal activity and cell cycle arrest at the G1 phase. We postulate that cellular senescence might be related to a hypoplastic defect in the DRG during neurodevelopment, as suggested by necropsy studies.

  14. CpG ODN佐剂对呼吸道合胞病毒重组疫苗诱导的细胞免疫应答的作用%Role of CpG ODN adjuvant in the cellular immune response induced by recombinant vaccine of respiratory syncytial virus

    Institute of Scientific and Technical Information of China (English)

    李娜; 刘建勋; 曾瑞红

    2011-01-01

    Objective :To investigate the role of CpG ODN adjuvant in the cellular immune responses induced by recombinant protein vaccine of respiratory syncytial virus (RSV ) .Methods :BALB /c mice were immunized i .n .or i .p .with G1F/M2+ CpG or G1F/M2+Al+ CpG three times .Spleens from the immunized mice were removed two weeks after the third immunization .Specific lytic activity was assessed using a LDH Cytotoxicity Assay Kit .IFN-γ-and IL-4-secreting cells were quantified using a ELISPOT kit .Percentages of CD4+ /CD8+ effector cells or LDH memory cells in the splenic cells of mice were analyzed with flow cytometer .Results :Immunization with G1F/M2+ CpG i .n .or i .p .induced significant specific lytic activity compared to G1F/M2 .The specific lytic activity induced by G1F/M2+Al+CpG (i .p . ) was significantly higher than that by G1F/M2+CpG (i .p .) .G1F/M2+CpG i .n .or i .p .induced significant more IFn-γ-secreting cells and IL-4secreting cells than G1F/M2 i .n .or i .p .significantly .The level of IFN-γ-secreting cells or IL-4-secreting cells in G1F/M2+Al+CpG (i .p . ) group was higher than that in G1F/M2+CpG (i .p . ) group .In addition ,the level of IFN-γ-secreting cells was remarkably higher than that of IL-4-secreting cells in each group ,suggesting a Th1 biased response ,which benefited for defensing virus .G1F/M2+CpG (i .n . ) induced only CD44+ CD62L - cells .G1F/M2+Al+ CpG (i.p .) or G1F/M2+CpG (i.p .) elicited both CD44+ CD62L- cells and CD44 + CD62L+ cells . Conclusion :CpG2216 ,as an adjuvant ,can enhance significantly the cellular immune responses of RSV recombinant vaccine G1F/M2 .%目的:研究CpG2216佐剂对呼吸道合胞病毒(RSV)重组蛋白疫苗诱导的细胞免疫应答的作用.方法:重组RSV疫苗G1F/M2与CpG2216佐剂混合,或与CpG2216及常规佐剂Al(OH)3混合,鼻腔(i.n.)或腹腔注射(i.p.)免疫BALB/c小鼠三次,最后一次免疫后2周杀小鼠,取脾细胞,用乳酸脱氢酶(LDH)释放法检测脾

  15. 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

  16. Glucose Oxidase Induces Cellular Senescence in Immortal Renal Cells through ILK by Downregulating Klotho Gene Expression.

    Science.gov (United States)

    Troyano-Suárez, Nuria; del Nogal-Avila, María; Mora, Inés; Sosa, Patricia; López-Ongil, Susana; Rodriguez-Puyol, Diego; Olmos, Gemma; Ruíz-Torres, María Piedad

    2015-01-01

    Cellular senescence can be prematurely induced by oxidative stress involved in aging. In this work, we were searching for novel intermediaries in oxidative stress-induced senescence, focusing our interest on integrin-linked kinase (ILK), a scaffold protein at cell-extracellular matrix (ECM) adhesion sites, and on the Klotho gene. Cultured renal cells were treated with glucose oxidase (GOx) for long time periods. GOx induced senescence, increasing senescence associated β-galactosidase activity and the expression of p16. In parallel, GOx increased ILK protein expression and activity. Ectopic overexpression of ILK in cells increased p16 expression, even in the absence of GOx, whereas downregulation of ILK inhibited the increase in p16 due to oxidative stress. Additionally, GOx reduced Klotho gene expression and cells overexpressing Klotho protein did not undergo senescence after GOx addition. We demonstrated a direct link between ILK and Klotho since silencing ILK expression in cells and mice increases Klotho expression and reduces p53 and p16 expression in renal cortex. In conclusion, oxidative stress induces cellular senescence in kidney cells by increasing ILK protein expression and activity, which in turn reduces Klotho expression. We hereby present ILK as a novel downregulator of Klotho gene expression. PMID:26583057

  17. Role of membrane and cellular oxidative damage in gamma radiation induced apoptotic death in mouse thymocytes

    International Nuclear Information System (INIS)

    Full text: Involvement of plasma membrane in the molecular mechanism of radiation-induced apoptotic death has increasingly been recognized by radiobiologists in the recent years. In present investigation, alterations in plasma membrane and the associated cytoplasmic / nuclear events were studied in apoptotic mouse thymocytes after gamma radiation exposure. The membrane oxidative damage in irradiated thymocytes was determined by thiobarbituric acid reactive species (TBARS) method and change in membrane permeability was estimated employing fluorescein diacetate (FDA) as fluorescent probe. Radiation-induced apoptotic thymocytes showed an increase in membrane permeability as observed by leakage of FDA, while trypan blue failed to respond. Moreover, using fluorescence technique, the changes in thymocytes membrane permeability could be sensitively determined within low to moderate radiation doses (2 cGy to 2 Gy). The dose dependent increase in intra-cellular reactive oxygen species (ROS) generation was found in irradiated thymocytes determined by fluorescence method, which could sensitively detect the radiation exposure in sub cGy range. Radiation induced membrane changes were found correlated with induction of apoptotic death determined by annexin-V method, caspase-3 assay, measuring nuclear diameter using propidium iodide (PI) staining and DNA fragmentation by gel electrophoresis. It has been also shown that membrane associated events observed in radiation induced apoptotic thymocytes are prior to nuclear / cytosolic processes. The membrane lipid peroxidation, cellular oxidative damage and apoptosis in radiation treated thymocytes were significantly inhibited by membrane-localized antioxidants suggesting significant contribution of membrane damage and oxidative stress in radiation mediated apoptosis in thymocytes

  18. Furfural induces reactive oxygen species accumulation and cellular damage in Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Slininger Patricia J

    2010-01-01

    Full Text Available Abstract Background Biofuels offer a viable alternative to petroleum-based fuel. However, current methods are not sufficient and the technology required in order to use lignocellulosic biomass as a fermentation substrate faces several challenges. One challenge is the need for a robust fermentative microorganism that can tolerate the inhibitors present during lignocellulosic fermentation. These inhibitors include the furan aldehyde, furfural, which is released as a byproduct of pentose dehydration during the weak acid pretreatment of lignocellulose. In order to survive in the presence of furfural, yeast cells need not only to reduce furfural to the less toxic furan methanol, but also to protect themselves and repair any damage caused by the furfural. Since furfural tolerance in yeast requires a functional pentose phosphate pathway (PPP, and the PPP is associated with reactive oxygen species (ROS tolerance, we decided to investigate whether or not furfural induces ROS and its related cellular damage in yeast. Results We demonstrated that furfural induces the accumulation of ROS in Saccharomyces cerevisiae. In addition, furfural was shown to cause cellular damage that is consistent with ROS accumulation in cells which includes damage to mitochondria and vacuole membranes, the actin cytoskeleton and nuclear chromatin. The furfural-induced damage is less severe when yeast are grown in a furfural concentration (25 mM that allows for eventual growth after an extended lag compared to a concentration of furfural (50 mM that prevents growth. Conclusion These data suggest that when yeast cells encounter the inhibitor furfural, they not only need to reduce furfural into furan methanol but also to protect themselves from the cellular effects of furfural and repair any damage caused. The reduced cellular damage seen at 25 mM furfural compared to 50 mM furfural may be linked to the observation that at 25 mM furfural yeast were able to exit the furfural-induced

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

    Directory of Open Access Journals (Sweden)

    UweKnippschild

    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.

  20. General aspects of the cellular response to low- and high-LET radiation

    International Nuclear Information System (INIS)

    Radiobiological studies have shown for some time that the effects of ionising radiation on cells are mainly explained by modification of the DNA. Numerous studies over the past 50 years have accumulated clear evidence of the cause-effect relationship between damage to DNA and the cytotoxic and mutagenic effects of ionising radiation. However, the path from irradiation of the cells to the induction of biological effects comprises several complex steps. The first step involves interactions between the radiation and the cellular environment. These consist of physical and chemical reactions which produce ions, excited molecules and radical species. Excitations and ionisations are complete in about 10-15 s, and are followed by a chemical thermal equilibrium of the species produced within 10-12 s. These species then diffuse from their site of production and provoke alterations to a variety of cellular components. This damage is detected by cellular surveillance systems, which in turn activate signalling cascades, gene transcription and enzyme recruitment, which participate in the cellular response. In most cases, cell cycle arrest occurs, allowing, according to the biological relevance of the DNA damage, either a process of DNA repair or programmed cell death (apoptosis). The accuracy of the DNA repair which is performed depends on the complexity of the DNA lesion and on the DNA repair machinery fidelity itself. Improper DNA repair can lead to mutation, chromosome aberration, genetic instability, oncogenic transformation and, ultimately, cell death. (orig.)

  1. Immune Responses to AAV in Canine Muscle Monitored by Cellular Assays and Noninvasive Imaging

    OpenAIRE

    Wang, Zejing; Storb, Rainer; Lee, Donghoon; Kushmerick, Martin J.; Chu, Baocheng; Berger, Carolina; Arnett, Andrea; Allen, James; Chamberlain, Jeffrey S.; Riddell, Stanley R.; Tapscott, Stephen J.

    2009-01-01

    We previously demonstrated that direct intramuscular injection of rAAV2 or rAAV6 in wild-type dogs resulted in robust T-cell responses to viral capsid proteins, and others have shown that cellular immunity to adeno-associated virus (AAV) capsid proteins coincided with liver toxicity and elimination of transgene expression in a human trial of hemophilia B. Here, we show that the heparin-binding ability of a given AAV serotype does not determine the induction of T-cell responses following intra...

  2. Dosimetric techniques for the evaluation of the EM power absorption induced by cellular phones

    International Nuclear Information System (INIS)

    International guidelines, ICNIRP, and proposed standards, IEEE-ANSI, define basic restrictions in terms of rate of power absorbed for mass unit (SAR) for localised exposure of electromagnetic fields such as in the near field region of cellular phones. Compliance tests of cellular phones consist in checking that emitted power from mobile telecommunication equipment (MTE) is below the reference levels and they are performed by assessing the absorbed power in specific head phantoms. The outcome of this work is the description of experimental procedures for evaluating SAR induced into the head by localised exposure. The set up instituted for compliance testing of MTE is described with the different components: dielectric simulators, electric field sensors, scanning system, remote control and data recording. Calibration procedures of E sensors and uncertainty evaluation of measures are presented. Finally the results of a comparison among a few European laboratories and of a test of some hand-set devices are shown. (author)

  3. A novel method to assess human population exposure induced by a wireless cellular network.

    Science.gov (United States)

    Varsier, Nadège; Plets, David; Corre, Yoann; Vermeeren, Günter; Joseph, Wout; Aerts, Sam; Martens, Luc; Wiart, Joe

    2015-09-01

    This paper presents a new metric to evaluate electromagnetic exposure induced by wireless cellular networks. This metric takes into account the exposure induced by base station antennas as well as exposure induced by wireless devices to evaluate average global exposure of the population in a specific geographical area. The paper first explains the concept and gives the formulation of the Exposure Index (EI). Then, the EI computation is illustrated through simple phone call scenarios (indoor office, in train) and a complete macro urban data long-term evolution scenario showing how, based on simulations, radio-planning predictions, realistic population statistics, user traffic data, and specific absorption rate calculations can be combined to assess the index. Bioelectromagnetics. 36:451-463, 2015. © 2015 Wiley Periodicals, Inc. PMID:26113174

  4. Autophagy induced by HIF1α overexpression supports trophoblast invasion by supplying cellular energy.

    Directory of Open Access Journals (Sweden)

    Mikiko Yamanaka-Tatematsu

    Full Text Available Extravillous trophoblasts (EVTs characterize the invasion of the maternal decidua under low oxygen and poor nutrition at the early feto-maternal interface to establish a successful pregnancy. We previously reported that autophagy in EVTs was activated under 2% O2 in vitro, and autophagy activation was also observed in EVTs at the early feto-maternal interface in vivo. Here, we show that autophagy is an energy source for the invasion of EVTs. Cobalt chloride (CoCl2, which induces hypoxia inducible factor 1α (HIF1α overexpression, activated autophagy in HTR8/SVneo cells, an EVT cell line. The number of invading HTR8-ATG4B(C74A cells, an autophagy-deficient EVT cell line, was markedly reduced by 81 percent with the CoCl2 treatment through the suppression of MMP9 level, although CoCl2 did not affect the cellular invasion of HTR8-mStrawberry cells, a control cell line. HTR8-ATG4B(C74A cells treated with CoCl2 showed a decrease in cellular adenosine triphosphate (ATP levels and a compensatory increase in the expression of purinergic receptor P2X ligand-gated ion channel 7 (P2RX7, which is stimulated with ATP, whereas HTR8-mStrawberry cells maintained cellular ATP levels and did not affect P2RX7 expression. Furthermore, the decreased invasiveness of HTR8-ATG4B(C74A cells treated with CoCl2 was neutralized by ATP supplementation to the level of HTR8-ATG4B(C74A cells treated without CoCl2. These results suggest that autophagy plays a role in maintaining homeostasis by countervailing HIF1α-mediated cellular energy consumption in EVTs.

  5. Analysis of cellular responses of macrophages to zinc ions and zinc oxide nanoparticles: a combined targeted and proteomic approach

    Science.gov (United States)

    Triboulet, Sarah; Aude-Garcia, Catherine; Armand, Lucie; Gerdil, Adèle; Diemer, Hélène; Proamer, Fabienne; Collin-Faure, Véronique; Habert, Aurélie; Strub, Jean-Marc; Hanau, Daniel; Herlin, Nathalie; Carrière, Marie; van Dorsselaer, Alain; Rabilloud, Thierry

    2014-05-01

    Two different zinc oxide nanoparticles, as well as zinc ions, are used to study the cellular responses of the RAW 264 macrophage cell line. A proteomic screen is used to provide a wide view of the molecular effects of zinc, and the most prominent results are cross-validated by targeted studies. Furthermore, the alteration of important macrophage functions (e.g. phagocytosis) by zinc is also investigated. The intracellular dissolution/uptake of zinc is also studied to further characterize zinc toxicity. Zinc oxide nanoparticles dissolve readily in the cells, leading to high intracellular zinc concentrations, mostly as protein-bound zinc. The proteomic screen reveals a rather weak response in the oxidative stress response pathway, but a strong response both in the central metabolism and in the proteasomal protein degradation pathway. Targeted experiments confirm that carbohydrate catabolism and proteasome are critical determinants of sensitivity to zinc, which also induces DNA damage. Conversely, glutathione levels and phagocytosis appear unaffected at moderately toxic zinc concentrations.Two different zinc oxide nanoparticles, as well as zinc ions, are used to study the cellular responses of the RAW 264 macrophage cell line. A proteomic screen is used to provide a wide view of the molecular effects of zinc, and the most prominent results are cross-validated by targeted studies. Furthermore, the alteration of important macrophage functions (e.g. phagocytosis) by zinc is also investigated. The intracellular dissolution/uptake of zinc is also studied to further characterize zinc toxicity. Zinc oxide nanoparticles dissolve readily in the cells, leading to high intracellular zinc concentrations, mostly as protein-bound zinc. The proteomic screen reveals a rather weak response in the oxidative stress response pathway, but a strong response both in the central metabolism and in the proteasomal protein degradation pathway. Targeted experiments confirm that carbohydrate

  6. Characterization of the cellular response triggered by gold nanoparticle-mediated laser manipulation

    Science.gov (United States)

    Kalies, Stefan; Keil, Sebastian; Sender, Sina; Hammer, Susanne C.; Antonopoulos, Georgios C.; Schomaker, Markus; Ripken, Tammo; Escobar, Hugo Murua; Meyer, Heiko; Heinemann, Dag

    2015-11-01

    Laser-based transfection techniques have proven high applicability in several cell biologic applications. The delivery of different molecules using these techniques has been extensively investigated. In particular, new high-throughput approaches such as gold nanoparticle-mediated laser transfection allow efficient delivery of antisense molecules or proteins into cells preserving high cell viabilities. However, the cellular response to the perforation procedure is not well understood. We herein analyzed the perforation kinetics of single cells during resonant gold nanoparticle-mediated laser manipulation with an 850-ps laser system at a wavelength of 532 nm. Inflow velocity of propidium iodide into manipulated cells reached a maximum within a few seconds. Experiments based on the inflow of FM4-64 indicated that the membrane remains permeable for a few minutes for small molecules. To further characterize the cellular response postmanipulation, we analyzed levels of oxidative heat or general stress. Although we observed an increased formation of reactive oxygen species by an increase of dichlorofluorescein fluorescence, heat shock protein 70 was not upregulated in laser-treated cells. Additionally, no evidence of stress granule formation was visible by immunofluorescence staining. The data provided in this study help to identify the cellular reactions to gold nanoparticle-mediated laser manipulation.

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

    International Nuclear Information System (INIS)

    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

  8. 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

  9. 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.

  10. Enhancing cellular immune response to HBV M DNA vaccine in mice by codelivery of interleukin-18 recombinant

    Institute of Scientific and Technical Information of China (English)

    陈建忠; 朱海红; 刘克洲; 陈智

    2004-01-01

    Objective: To investigate the effect of interleukin-18 (IL-18) on immune response induced by plasmid encoding hepatitis B virus middle protein antigen and to explore new strategies for prophylactic and therapeutic HBV DNA vaccines. Methods: BALB/c mice were immunized with pCMV-M alone or co-immunized with pcDNA3-18 and pCMV-M and then their sera were collected for analysing anti-HBsAg antibody by ELISA; splenocytes were isolated for detecting specific CTL response and cytokine assay in vitro. Results: The anti-HBs antibody level of mice co-immunized with pcDNA3-18 and pCMV-M was slightly higher than that of mice immunized with pCMV-M alone, but there was not significantly different (P>0.05). Compared with mice injected with pCMV-M, the specific CTL cytotoxity activity of mice immunized with pcDNA3-18 and pCMV-M was significantly enhanced (P0.05). Conclusion: The plasmid encoding IL-18 together with HBV M gene DNA vaccines may enhance specific TH1 cells and CTL cellular immune response induced in mice, so that IL-18 is a promising immune adjuvant.

  11. Enhancing cellular immune response to HBV M DNA vaccine in mice by codelivery of interleukin-18 recombinant

    Institute of Scientific and Technical Information of China (English)

    陈建忠; 朱海红; 刘克洲; 陈智

    2004-01-01

    Objective:To investigate the effect of interleukin-18 (IL-18) on immune response induced by plasmid encoding hepatitis B virus middle protein antigen and to explore new strategies for prophylactic and therapeutic HBV DNA vaccines.Methods:BALB/c mice were immunized with pCMV-M alone or co-immunized with pcDNA3-18 and pCMV-M and then their sera were collected for analysing anti-HBsAg antibody by ELISA;splenocytes were isolated for detecting specific CTL response and cytokine assay in vitro.Results:The anti-HBs antibody level of mice co-immunized with pcDNA3-18 and pCMV-M was slightly higher than that of mice immunized with pCMV-M alone,but there was not significantly different (P>0.05).Compared with mice injected with pCMV-M, the specific CTL cytotoxity activity of mice immunized with pcDNA3-18 and pCMV-M was significantly enhanced (P0.05).Conclusion:The plasmid encoding IL-18 together with HBV M gene DNA vaccines may enhance specific TH1 cells and CTL cellular immune response induced in mice, so that IL-18 is a promising immune adjuvant.

  12. Cytokines, Chaperones and Neuroinflammatory Responses in Heroin-Related Death: What Can We Learn from Different Patterns of Cellular Expression?

    Directory of Open Access Journals (Sweden)

    Vittorio Fineschi

    2013-09-01

    Full Text Available Heroin (3,6-diacetylmorphine has various effects on the central nervous system with several neuropathological alterations including hypoxic-ischemic brain damage from respiratory depressing effects and neuroinflammatory response. Both of these mechanisms induce the release of cytokines, chemokines and other inflammatory mediators by the activation of many cell types such as leucocytes and endothelial and glial cells, especially microglia, the predominant immunocompetent cell type within the central nervous system. The aim of this study is to clarify the correlation between intravenous heroin administration in heroin related death and the neuroinflammatory response. We selected 45 cases among autopsies executed for heroin-related death (358 total cases; immunohistochemical studies and Western blotting analyses were used to investigate the expression of brain markers such as tumor necrosis factor-α, oxygen-regulated protein 150, (interleukins IL-1β, IL-6, IL-8, IL-10, IL-15, cyclooxygenase-2, heat shock protein 70, and CD68 (MAC387. Findings demonstrated that morphine induces inflammatory response and cytokine release. In particular, oxygen-regulated protein 150, cyclooxygenase-2, heat shock protein 70, IL-6 and IL-15 cytokines were over-expressed with different patterns of cellular expression.

  13. The relationship between cellular radiosensitivity and radiation-induced DNA damage measured by the comet assay

    International Nuclear Information System (INIS)

    The relationship between deoxyribonucleic acid (DNA) damage and the cell death induced by γ-irradiation was examined in three kinds of cells, Chinese hamster ovary fibroblast CHO-K1, human melanoma HMV-II and mouse leukemia L5178Y. Cell survival was determined by a clonogenic assay. The induction and rejoining of DNA strand breaks induced by radiation were measured by the alkaline and neutral comet assay. L5178Y cells were the most radiosensitive, while CHO-K1 cells and HMV-II cells were radioresistant. There was an inverse relationship between the survival fraction at 2 Gy (SF2) and the yield of initial DNA strand breaks per unit dose under the alkaline condition of the comet assay, and also a relationship between SF2 and the residual DNA strand breaks (for 4 hr after irradiation) under the neutral condition for the comet assay, the latter being generally considered to be relative to cellular radiosensitivity. In the present analysis, it was considered that the alkaline condition for the comet assay was optimal for evaluating the initial DNA strand breaks, while the neutral condition was optimal for evaluating the residual DNA strand breaks. Since the comet assay is simpler and more rapid than other methods for detecting radiation-induced DNA damage, this assay appears to be a useful predictive assay for evaluating cellular clonogenic radiosensitivity of tumor cells. (author)

  14. Strain variations in the murine cellular immune response to the phenolic glycolipid I antigen of Mycobacterium leprae.

    Science.gov (United States)

    Koster, F T; Teuscher, C; Matzner, P; Umland, E; Yanagihara, D; Brennan, P J; Tung, K S

    1986-01-01

    The cellular immune response to the Mycobacterium leprae-specific phenolic glycolipid I was examined in inbred mice immunized with M. leprae by in vivo delayed cutaneous hypersensitivity and in vitro lymphocyte proliferation. Whereas all mouse strains responded to M.leprae-induced delayed-type hypersensitivity and lymphocyte proliferation, only BALB.K was responsive in both assays to the glycolipid. Responsiveness was determined in part by non-H-2 genes, while the influence of H-2 genes was not apparent. Among congenic BALB/c mice differing only at Igh-C allotype loci, variations in responsiveness were found in both delayed-type hypersensitivity and lymphocytes proliferation assays, indicating a possible role for Igh-C loci-linked genes. Unresponsiveness in the lymphocyte proliferation assay to the glycolipid was inherited as a dominant trait in one set of responder X nonresponder F1 progeny. We conclude that after immunization with M. leprae organisms, the cell-mediated responses to the glycolipid, endowed with a single carbohydrate epitope, are under polygenic control, predominantly non-H-2-linked genes. PMID:3510979

  15. Strategies to Potentiate the Cellular Poly(ADP-ribosyl)ation Response to DNA Damage

    OpenAIRE

    Kunzmann, Andrea

    2009-01-01

    Poly(ADP-ribosyl)ation is a posttranslational modification of cellular proteins, which is mainly catalyzed by poly(ADP-ribose) polymerase 1 (PARP1) by using NAD+ as substrate. The catalytic activity of PARP1 is known to be triggered by the binding of PARP1 to broken DNA via its two aminoterminal zinc finger motifs. DNA strand break-induced poly(ADP-ribosyl)ation is linked to DNA repair and maintenance of genomic stability.Up to now, little information exists on the biological consequences of ...

  16. Enhancing repair of radiation-induced strand breaks in cellular DNA as a radiotherapeutic potential

    International Nuclear Information System (INIS)

    Protection of mammalian organisms including man from deleterious effects of ionizing radiation is of paramount importance and development of effective approaches to combat radiation damages using non-toxic radioprotectors is of considerable interest for defence, nuclear industries, radiation accidents, space travels, etc., besides the protection of normal tissues during radiotherapy of tumours. Many synthetic as well as natural compounds have been investigated in the recent past for their efficacy to protect the biological systems from radiation induced damages. They include sulfhydryl compounds, antioxidants, plant extracts, immune-modulators, and other agents. However, the inherent toxicity of many of the synthetic agents at the effective radio-protective concentration warranted further search for safer and more effective radio-protectors. In this context, therapeutic radioprotectors which are effective on post irradiation administration are of special relevance. One of the property that can be applied while screening for such radiation protective therapeutics is their ability to enhance repair of radiation-induced lesions in cellular DNA in terms of cellular repair index based on the parameters of the DNA following comet assay. Post irradiation administration of some natural and synthetic agents have shown their potential to enhance repair of radiation-induced strand breaks in cellular DNA in mice. These include phytoceuticals such as gallic acid, sesamol etc., extracts of medicinal plants such as Andrographis panniculata, and a few synthetic compounds such as tocopherol-mono-glucoside. The talk will give an overview of the work on DNA repair enhancement by a few natural and synthetic agents. (author)

  17. Radioadaptive response viewed from the relationship with reactive oxygen species and anti oxidative cellular capability

    International Nuclear Information System (INIS)

    Radiation-induced adaptive response (PAR) is a phenomenon manifesting as a priming low dose-induced resistance against a subsequent irradiation at higher dose. To understand this biological defensive phenomenon against radiation, it is important to study from the mechanistic point of view of two basic aspects: One is the antioxidative capability to scavenge the reactive oxygen species generated by radiation, and the other is the capability to repair radiation-induced damages. In this review, we summarize the knowledge of reactive oxygen species, and discuss the relationship between the low dose-induced increase in antioxidative activity and PAR. (author)

  18. 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.

  19. 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...

  20. 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.

  1. 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.

  2. Protein tyrosine phosphatase is possibly involved in cellular signal transduction and the regulation of ABA accumulation in response to water deficit in Maize L. coleoptile

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Water deficit-induced ABA accumulation is an ideal model or "stimulus-response" system to investigate cellular stress signaling in plant cells, using such a model the cellular stress signaling triggered by water deficit was investigated in Maize L. coleoptile. Water deficit-induced ABA accumulation was sensitively blocked by NaVO3, a potent inhibitor both to plasma membrane H+-ATPase (PM-H+- ATPase) and protein tyrosine phosphatase (PTPase). However, while PM- H+-ATPase activity was unaffected under water deficit and PM- H+-ATPase activator did not induce an ABA accumulation instead of water deficit, water deficit induced an increase in the protein phosphatase activity, and furthermore, ABA accumulation was inhibited by PAO, a specific inhibitor of PTPase. These results indicate that protein phosphtases may be involved in the cellular signaling in response to water deficit. Further studies identified at least four species of protein phosphtase as assayed by using pNPP as substrate, among which one component was especially sensitive to NaVO3. The NaVO3-sensitive enzyme was purified and finally showed a protein band about 66 kD on SDS/PAGE. The purified enzyme showed a great activity to some specific PTPase substrates at pH 6.0. In addition to NaVO3, the enzyme was also sensitive to some other PTPase inhibitors such as Zn2+ and MO33+, but not to Ca2+ and Mg2+, indicating that it might be a protein tyrosine phosphatase. Interestingly, the purified enzyme could be deactivated by some reducing agent DTT, which was previously proved to be an inhibitor of water deficit-induced ABA accumulation. This result further proved that PTPase might be involved in the cellular signaling of ABA accumulation in response to water deficit.

  3. Mapping Variation in Cellular and Transcriptional Response to 1,25-Dihydroxyvitamin D3 in Peripheral Blood Mononuclear Cells.

    Science.gov (United States)

    Kariuki, Silvia N; Maranville, Joseph C; Baxter, Shaneen S; Jeong, Choongwon; Nakagome, Shigeki; Hrusch, Cara L; Witonsky, David B; Sperling, Anne I; Di Rienzo, Anna

    2016-01-01

    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 FDRvitamin 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. PMID:27454520

  4. Molecular events basic to cellular radiation response. Progress report, July 1, 1976--September 30, 1977

    International Nuclear Information System (INIS)

    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

  5. Polyhydroxylated fullerene attenuates oxidative stress-induced apoptosis via a fortifying Nrf2-regulated cellular antioxidant defence system

    Directory of Open Access Journals (Sweden)

    Ye SF

    2014-04-01

    Full Text Available Shefang Ye,1 Min Chen,1 Yuanqin Jiang,1,2 Mingliang Chen,3 Tong Zhou,1 Yange Wang,1 Zhenqing Hou,1 Lei Ren11Department of Biomaterials, Research Center of Biomedical Engineering, College of Materials, Xiamen University, Xiamen, People's Republic of China; 2First Affiliated Hospital of Xiamen University, Xiamen, People's Republic of China; 3Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen, People's Republic of ChinaAbstract: Polyhydroxylated derivatives of fullerene C60, named fullerenols (C60[OH]n, have stimulated great interest because of their potent antioxidant properties in various chemical and biological systems, which enable them to be used as a new promising pharmaceutical for the future treatment of oxidative stress-related diseases, but the details remain unknown. Nuclear factor erythroid 2-related factor 2 (Nrf2 is a principal transcription factor that regulates expression of several antioxidant genes via binding to the antioxidant response element and plays a crucial role in cellular defence against oxidative stress. In this study we investigated whether activation of the Nrf2/antioxidant response element pathway contributes to the cytoprotective effects of C60(OH24. Our results showed that C60(OH24 enhanced nuclear translocation of Nrf2 and upregulated expression of phase II antioxidant enzymes, including heme oxygenase-1 (HO-1, NAD(PH: quinine oxidoreductase 1, and γ-glutamate cysteine ligase in A549 cells. Treatment with C60(OH24 resulted in phosphorylation of p38 mitogen-activated protein kinases (p38 MAPK, extracellular signal-regulated kinases, and c-Jun-N-terminal kinases. By using inhibitors of cellular kinases, we showed that pretreatment of A549 cells with SB203580, a specific inhibitor of p38 MAPK, abolished nuclear translocation of Nrf2 and induction of HO-1 protein induced by C60(OH24, indicating an involvement of p38 MAPK in Nrf2/HO-1 activation by C60

  6. ST1571 (imatinib mesylate) reduces bone marrow cellularity and normalizes morphologic features irrespective of cytogenetic response.

    Science.gov (United States)

    Hasserjian, Robert P; Boecklin, Federica; Parker, Sally; Chase, Andy; Dhar, Sunanda; Zaiac, Michael; Olavarria, Eduardo; Lampert, Irvin; Henry, Kristin; Apperley, Jane F; Goldman, John M

    2002-03-01

    The tyrosine kinase inhibitor STI571 (imatinib mesylate, Gleevec) is an effective treatment for chronic myeloid leukemia (CML). We examined bone marrow samples from 53 patients with CML who were receiving STI571 in 3 multicenter phase 2 trials to assess morphologic changes and cytogenetic response to this drug. In most patients with initially increased blasts, the bone marrow blast count rapidly decreased during STI571 therapy. Reductions in cellularity, the myeloid/erythroid ratio (commonly with relative erythroid hyperplasia), and reticulin fibrosis (if present pretreatment) also were seen in most patients, resulting in an appearance resembling normal marrow in many cases. Eighteen patients (34%) had some degree of cytogenetic response. Surprisingly, these striking morphologic changes occurred irrespective of any cytogenetic response to STI571. Thus, STI571 seems to affect the differentiation of CML cells in vivo, causing even extensively Philadelphia chromosome-positive hematopoiesis to exhibitfeatures resembling normal hematopoiesis. PMID:11888075

  7. 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, and...... transcription blocks, invoking acute and selective displacement of the factors AZI1/CEP131, PCM1, and CEP290 from this compartment triggered by activation of the stress-responsive kinase p38/MAPK14. We demonstrate that the E3 ubiquitin ligase MIB1 is a new component of centriolar satellites, which interacts...... with and ubiquitylates AZI1 and PCM1 and suppresses primary cilium formation. In response to cell stress, MIB1 is abruptly inactivated in a p38-independent manner, leading to loss of AZI1, PCM1, and CEP290 ubiquitylation and concomitant stimulation of ciliogenesis, even in proliferating cells...

  8. A biphasic endothelial stress-survival mechanism regulates the cellular response to vascular endothelial growth factor A

    International Nuclear Information System (INIS)

    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: ► Endothelial cells mount a stress response under conditions of low serum. ► Endothelial VEGFR levels are

  9. 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

  10. Advancing nanograined/ultrafine-grained structures for metal implant technology: Interplay between grooving of nano/ultrafine grains and cellular response

    International Nuclear Information System (INIS)

    Nanograined/ultrafine-grained (NG/UFG) metals provide surfaces that are different from conventional coarse-grained polycrystalline metals because of the high fraction of grain boundaries. In the context of osseointegration of metal implants, grooving of nanograins/ultrafine grains by electrochemical grooving is a potential approach to increase the biomechanical interlocking and anchorage with consequent enhancement of cellular response. The primary objective of the research described here is to advance science and technology of metal implants by making a relative comparison of osteoblast response of grain boundary grooved and planar NG/UFG surfaces. The NG/UFG substrates were obtained using an ingenious concept of controlled phase reversion and the grain boundaries were electrochemically treated to induce grooving of large fraction of grain boundaries of NG/UFG substrate. Experiments on the effect of grooving of grain boundaries of NG/UFG metal indicated that cell attachment, proliferation, viability, morphology, and spread are favorably modulated and significantly different from planar (non-grooved) NG/UFG substrates. Furthermore, immunofluorescence studies demonstrated stronger vinculin signals associated with actin stress fibers in the outer regions of the cells and cellular extensions on electrochemically grooved NG/UFG substrate. These observations are indicative of accelerated response of cell-substrate interaction and activity. The differences in the cellular response of planar and grain boundary grooved NG/UFG surface are attributed to favorable surface topography that accelerates the cellular activity.

  11. Advancing nanograined/ultrafine-grained structures for metal implant technology: Interplay between grooving of nano/ultrafine grains and cellular response

    Energy Technology Data Exchange (ETDEWEB)

    Venkatsurya, P.K.C; Thein-Han, W.W. [Biomaterials and Biomedical Engineering Research Laboratory, Center for Structural and Functional Materials, University of Louisiana at Lafayette, P.O. Box 44130, Lafayette, LA 70504 (United States); Misra, R.D.K., E-mail: dmisra@louisiana.edu [Biomaterials and Biomedical Engineering Research Laboratory, Center for Structural and Functional Materials, University of Louisiana at Lafayette, P.O. Box 44130, Lafayette, LA 70504 (United States); Somani, M.C.; Karjalainen, L.P. [Department of Mechanical Engineering, University of Oulu, P.O. Box 4200, 90014 Oulu (Finland)

    2010-08-30

    Nanograined/ultrafine-grained (NG/UFG) metals provide surfaces that are different from conventional coarse-grained polycrystalline metals because of the high fraction of grain boundaries. In the context of osseointegration of metal implants, grooving of nanograins/ultrafine grains by electrochemical grooving is a potential approach to increase the biomechanical interlocking and anchorage with consequent enhancement of cellular response. The primary objective of the research described here is to advance science and technology of metal implants by making a relative comparison of osteoblast response of grain boundary grooved and planar NG/UFG surfaces. The NG/UFG substrates were obtained using an ingenious concept of controlled phase reversion and the grain boundaries were electrochemically treated to induce grooving of large fraction of grain boundaries of NG/UFG substrate. Experiments on the effect of grooving of grain boundaries of NG/UFG metal indicated that cell attachment, proliferation, viability, morphology, and spread are favorably modulated and significantly different from planar (non-grooved) NG/UFG substrates. Furthermore, immunofluorescence studies demonstrated stronger vinculin signals associated with actin stress fibers in the outer regions of the cells and cellular extensions on electrochemically grooved NG/UFG substrate. These observations are indicative of accelerated response of cell-substrate interaction and activity. The differences in the cellular response of planar and grain boundary grooved NG/UFG surface are attributed to favorable surface topography that accelerates the cellular activity.

  12. Toll-like receptors: cellular signal transducers for exogenous molecular patterns causing immune responses.

    Science.gov (United States)

    Kirschning, C J; Bauer, S

    2001-09-01

    Innate immunity initiates protection of the host organism against invasion and subsequent multiplication of microbes by specific recognition. Germ line-encoded receptors have been identified for microbial products such as mannan, lipopeptide, peptidoglycan (PGN), lipoteichoic acid (LTA), lipopolysaccharide (LPS), and CpG-DNA. The Drosophila Toll protein has been shown to be involved in innate immune response of the adult fruitfly. Members of the family of Toll-like receptors (TLRs) in vertebrates have been implicated as pattern recognition receptors (PRRs). Ten TLRs are known and six of these have been demonstrated to mediate cellular activation by distinct microbial products. TLR4 has been implicated as activator of adaptive immunity, and analysis of systemic LPS responses in mice led to the identification of LPS-resistant strains instrumental in its identification as a transmembrane LPS signal transducer. Structural similarities between TLRs and receptor molecules involved in immune responses such as CD14 and the IL-1 receptors (IL-1Rs), as well as functional analysis qualified TLR2 as candidate receptor for LPS and other microbial products. Targeted disruption of the TLR9 gene in mice led to identification of TLR9 as CpG-DNA signal transducer. Involvement of TLR5 in cell activation by bacterial flagellin has been demonstrated. Further understanding of recognition and cellular signaling activated through the ancient host defense system represented by Toll will eventually lead to means for its therapeutic modulation. PMID:11680785

  13. Analysis of cellular responses of macrophages to zinc ions and zinc oxide nanoparticles: a combined targeted and proteomic approach.

    Science.gov (United States)

    Triboulet, Sarah; Aude-Garcia, Catherine; Armand, Lucie; Gerdil, Adèle; Diemer, Hélène; Proamer, Fabienne; Collin-Faure, Véronique; Habert, Aurélie; Strub, Jean-Marc; Hanau, Daniel; Herlin, Nathalie; Carrière, Marie; Van Dorsselaer, Alain; Rabilloud, Thierry

    2014-06-01

    Two different zinc oxide nanoparticles, as well as zinc ions, are used to study the cellular responses of the RAW 264 macrophage cell line. A proteomic screen is used to provide a wide view of the molecular effects of zinc, and the most prominent results are cross-validated by targeted studies. Furthermore, the alteration of important macrophage functions (e.g. phagocytosis) by zinc is also investigated. The intracellular dissolution/uptake of zinc is also studied to further characterize zinc toxicity. Zinc oxide nanoparticles dissolve readily in the cells, leading to high intracellular zinc concentrations, mostly as protein-bound zinc. The proteomic screen reveals a rather weak response in the oxidative stress response pathway, but a strong response both in the central metabolism and in the proteasomal protein degradation pathway. Targeted experiments confirm that carbohydrate catabolism and proteasome are critical determinants of sensitivity to zinc, which also induces DNA damage. Conversely, glutathione levels and phagocytosis appear unaffected at moderately toxic zinc concentrations. PMID:24788578

  14. Cellular Immune Response of Weaned Pigs Fed Diet Supplemented with an Essential Oil

    OpenAIRE

    János Tossenberger; Róbert Tóthi; Csaba Szabó; Zsuzsanna Pásti; Imre Nochta; Veronika Halas; László Babinszky

    2011-01-01

    The objective of the present study was to investigate the effect of an essential oil product on growth performance and cellular immune response of 28-day-old weaned piglets. A total of 348 piglets (50% gilts, 50% barrows) were assigned to three dietary treatments (6 pens/trt). Th e basal diet was a commercial feed that was supplemented without any growth promoter (NC), with antibiotic growth promoter of 40 ppm avilamycin (PC), or with 0.25 g of an essential oil product (EO) per kg of feed. Al...

  15. Comparison of Yarrowia lipolytica and Pichia pastoris cellular response to different agents of oxidative stress

    OpenAIRE

    Lopes, Marlene; Mota, M.; Belo, Isabel

    2013-01-01

    Yeast cells exposed to adverse conditions employ a number of defense mechanisms in order to respond effectively to the stress effects of reactive oxygen species. In this work, the cellular response of Yarrowia lipolytica and Pichia pastoris to the exposure to the ROSinducing agents’ paraquat, hydrogen peroxide, and increased air pressure was analyzed. Yeast cells at exponential phase were exposed for 3 h to 1 mM paraquat, to 50 mM H2O2, or to increased air pressure of 3 or 5 bar. For both str...

  16. 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.

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

    Science.gov (United States)

    Nikiforov, M. P.; Reukov, V. V.; Thompson, G. L.; Vertegel, A. A.; Guo, S.; Kalinin, S. V.; Jesse, S.

    2009-10-01

    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.

  18. A germline polymorphism of DNA polymerase beta induces genomic instability and cellular transformation.

    Directory of Open Access Journals (Sweden)

    Jennifer Yamtich

    Full Text Available Several germline single nucleotide polymorphisms (SNPs have been identified in the POLB gene, but little is known about their cellular and biochemical impact. DNA Polymerase β (Pol β, encoded by the POLB gene, is the main gap-filling polymerase involved in base excision repair (BER, a pathway that protects the genome from the consequences of oxidative DNA damage. In this study we tested the hypothesis that expression of the POLB germline coding SNP (rs3136797 in mammalian cells could induce a cancerous phenotype. Expression of this SNP in both human and mouse cells induced double-strand breaks, chromosomal aberrations, and cellular transformation. Following treatment with an alkylating agent, cells expressing this coding SNP accumulated BER intermediate substrates, including single-strand and double-strand breaks. The rs3136797 SNP encodes the P242R variant Pol β protein and biochemical analysis showed that P242R protein had a slower catalytic rate than WT, although P242R binds DNA similarly to WT. Our results suggest that people who carry the rs3136797 germline SNP may be at an increased risk for cancer susceptibility.

  19. 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.

  20. Induction of multixenobiotic defense mechanisms in resistant Daphnia magna clones as a general cellular response to stress.

    Science.gov (United States)

    Jordão, Rita; Campos, Bruno; Lemos, Marco F L; Soares, Amadeu M V M; Tauler, Romà; Barata, Carlos

    2016-06-01

    Multixenobiotic resistance mechanisms (MXR) were recently identified in Daphnia magna. Previous results characterized gene transcripts of genes encoding and efflux activities of four putative ABCB1 and ABCC transporters that were chemically induced but showed low specificity against model transporter substrates and inhibitors, thus preventing us from distinguishing between activities of different efflux transporter types. In this study we report on the specificity of induction of ABC transporters and of the stress protein hsp70 in clones selected to be genetically resistant to ABCB1 chemical substrates. Clones resistant to mitoxantrone, ivermectin and pentachlorophenol showed distinctive transcriptional responses of transporter protein coding genes and of putative transporter dye activities. Expression of hsp70 proteins also varied across resistant clones. Clones resistant to mitoxantrone and pentachlorophenol showed high constitutive levels of hsp70. Transcriptional levels of the abcb1 gene transporter and of putative dye transporter activity were also induced to a greater extent in the pentachlorophenol resistant clone. Observed higher dye transporter activities in individuals from clones resistant to mitoxantrone and ivermectin were unrelated with transcriptional levels of the studied four abcc and abcb1 transporter genes. These findings suggest that Abcb1 induction in D. magna may be a part of a general cellular stress response. PMID:27039215

  1. Quantitative PCR evaluation of cellular immune responses in Kenyan children vaccinated with a candidate malaria vaccine.

    Directory of Open Access Journals (Sweden)

    Jedidah Mwacharo

    Full Text Available BACKGROUND: The T-cell mediated immune response plays a central role in the control of malaria after natural infection or vaccination. There is increasing evidence that T-cell responses are heterogeneous and that both the quality of the immune response and the balance between pro-inflammatory and regulatory T-cells determines the outcome of an infection. As Malaria parasites have been shown to induce immunosuppressive responses to the parasite and non-related antigens this study examined T-cell mediated pro-inflammatory and regulatory immune responses induced by malaria vaccination in children in an endemic area to determine if these responses were associated with vaccine immunogenicity. METHODS: Using real-time RT- PCR we profiled the expression of a panel of key markers of immunogenecity at different time points after vaccination with two viral vector vaccines expressing the malaria TRAP antigen (FP9-TRAP and MVA-TRAP or following rabies vaccination as a control. PRINCIPAL FINDINGS: The vaccine induced modest levels of IFN-gamma mRNA one week after vaccination. There was also an increase in FoxP3 mRNA expression in both TRAP stimulated and media stimulated cells in the FFM ME-TRAP vaccine group; however, this may have been driven by natural exposure to parasite rather than by vaccination. CONCLUSION: Quantitative PCR is a useful method for evaluating vaccine induced cell mediated immune responses in frozen PBMC from children in a malaria endemic country. Future studies should seek to use vaccine vectors that increase the magnitude and quality of the IFN-gamma immune response in naturally exposed populations and should monitor the induction of a regulatory T cell response.

  2. Mycobacterium bovis BCG priming induces a strong potentiation of the antibody response induced by recombinant BCG expressing a foreign antigen.

    OpenAIRE

    Gheorghiu, M; Lagranderie, M R; Gicquel, B M; Leclerc, C D

    1994-01-01

    Several recent studies have demonstrated that strong cellular or humoral immune responses can be induced against foreign antigens expressed by recombinant Mycobacterium bovis BCG. It has therefore been suggested that BCG could represent one of the best candidate vectors for live recombinant vaccines. However, a large percentage of the human population has been immunized by BCG, and this priming could modify the immune response to future recombinant BCG vaccines. In the present study, we have ...

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

    OpenAIRE

    Elza Ibrahim Auerkari; Ismu Suharsono Suwelo; Achmad Tjarta; Santoso Cornain; T. W. Rahardjo; Eto, K; Ikeda, M.A

    2015-01-01

    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 l...

  4. Cellular immune responses to HPV-18, -31, and -53 in healthy volunteers immunized with recombinant HPV-16 L1 virus-like particles

    International Nuclear Information System (INIS)

    Human papillomavirus-like particles (HPV VLP) are candidate vaccines that have shown to be efficacious in reducing infection and inducing robust antiviral immunity. Neutralizing antibodies generated by vaccination are largely type-specific, but little is known about the type-specificity of cellular immune responses to VLP vaccination. To determine whether vaccination with HPV-16 L1VLP induces cellular immunity to heterologous HPV types (HPV-18, HPV-31, and HPV-53), we examined proliferative and cytokine responses in vaccine (n = 11) and placebo (n = 5) recipients. Increased proliferative and cytokine responses to heterologous types were observed postvaccination in some individuals. The proportion of women responding to heterologous types postvaccination (36%-55%) was lower than that observed in response to HPV-16 (73%). Response to HPV-16 VLP predicted response to other types. The strongest correlations in response were observed between HPV-16 and HPV-31, consistent with their phylogenetic relatedness. In summary, PBMC from HPV-16 VLP vaccine recipients can respond to L1VLP from heterologous HPV types, suggesting the presence of conserved T cell epitopes

  5. Radiation-induced gene responses

    International Nuclear Information System (INIS)

    In the process of identifying genes that are differentially regulated in cells exposed to ultraviolet radiation (UV), we identified a transcript that was repressed following the exposure of cells to a combination of UV and salicylate, a known inhibitor of NF-kappaB. Sequencing this band determined that it has identify to lactate dehydrogenase, and Northern blots confirmed the initial expression pattern. Analysis of the sequence of the LDH 5' region established the presence of NF-kappaB, Sp1, and two Ap-2 elements; two partial AP- 1; one partial RE, and two halves of E-UV elements were also found. Electromobility shift assays were then performed for the AP-1, NF- kappaB, and E-UV elements. These experiments revealed that binding to NF-kappaB was induced by UV but repressed with salicylic acid; UV did not affect AP-1 binding, but salicylic acid inhibited it alone or following UV exposure; and E-UV binding was repressed by UV, and salicylic acid had little effect. Since the binding of no single element correlated with the expression pattern of LDH, it is likely that multiple elements govern UV/salicylate-mediated expression

  6. A small molecule that induces reactive oxygen species via cellular glutathione depletion.

    Science.gov (United States)

    Kawamura, Tatsuro; Kondoh, Yasumitsu; Muroi, Makoto; Kawatani, Makoto; Osada, Hiroyuki

    2014-10-01

    Induction of excessive levels of reactive oxygen species (ROS) by small-molecule compounds has been considered a potentially effective therapeutic strategy against cancer cells, which are often subjected to chronic oxidative stress. However, to elucidate the mechanisms of action of bioactive compounds is generally a time-consuming process. We have recently identified NPD926, a small molecule that induces rapid cell death in cancer cells. Using a combination of two comprehensive and complementary approaches, proteomic profiling and affinity purification, together with the subsequent biochemical assays, we have elucidated the mechanism of action underlying NPD926-induced cell death: conjugation with glutathione mediated by GST, depletion of cellular glutathione and subsequent ROS generation. NPD926 preferentially induced effects in KRAS-transformed fibroblast cells, compared with their untransformed counterparts. Furthermore, NPD926 sensitized cells to inhibitors of system x(c)⁻, a cystine-glutamate antiporter considered to be a potential therapeutic target in cancers including cancer stem cells. These data show the effectiveness of a newly identified ROS inducer, which targets glutathione metabolism, in cancer treatment. PMID:25011393

  7. Cellular Response to a Novel Fetal Acellular Collagen Matrix: Implications for Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    Robert C. Rennert

    2013-01-01

    Full Text Available Introduction. PriMatrix (TEI Biosciences Inc., Boston, MA, USA is a novel acellular collagen matrix derived from fetal bovine dermis that is designed for use in partial- and full-thickness wounds. This study analyzes the cellular response to PriMatrix in vivo, as well as the ability of this matrix to facilitate normal tissue regeneration. Methods. Five by five mm squares of rehydrated PriMatrix were implanted in a subcutaneous fashion on the dorsum of wild-type mice. Implant site tissue was harvested for histology, immunohistochemistry (IHC, and flow cytometric analyses at multiple time points until day 28. Results. PriMatrix implants were found to go through a biological progression initiated by a transient infiltrate of inflammatory cells, followed by mesenchymal cell recruitment and vascular development. IHC analysis revealed that the majority of the implanted fetal dermal collagen fibers persisted through day 28 but underwent remodeling and cellular repopulation to form tissue with a density and morphology consistent with healthy dermis. Conclusions. PriMatrix implants undergo progressive in vivo remodeling, facilitating the regeneration of histologically normal tissue through a mild inflammatory and progenitor cell response. Regeneration of normal tissue is especially important in a wound environment, and these findings warrant further investigation of PriMatrix in this setting.

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

    International Nuclear Information System (INIS)

    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

  9. Meta-Analysis of High-Throughput Datasets Reveals Cellular Responses Following Hemorrhagic Fever Virus Infection

    Directory of Open Access Journals (Sweden)

    Gavin C. Bowick

    2011-05-01

    Full Text Available The continuing use of high-throughput assays to investigate cellular responses to infection is providing a large repository of information. Due to the large number of differentially expressed transcripts, often running into the thousands, the majority of these data have not been thoroughly investigated. Advances in techniques for the downstream analysis of high-throughput datasets are providing additional methods for the generation of additional hypotheses for further investigation. The large number of experimental observations, combined with databases that correlate particular genes and proteins with canonical pathways, functions and diseases, allows for the bioinformatic exploration of functional networks that may be implicated in replication or pathogenesis. Herein, we provide an example of how analysis of published high-throughput datasets of cellular responses to hemorrhagic fever virus infection can generate additional functional data. We describe enrichment of genes involved in metabolism, post-translational modification and cardiac damage; potential roles for specific transcription factors and a conserved involvement of a pathway based around cyclooxygenase-2. We believe that these types of analyses can provide virologists with additional hypotheses for continued investigation.

  10. Cellular Response to Doping of High Porosity Foamed Alumina with Ca, P, Mg, and Si

    Directory of Open Access Journals (Sweden)

    Edwin Soh

    2015-03-01

    Full Text Available Foamed alumina was previously synthesised by direct foaming of sulphate salt blends varying ammonium mole fraction (AMF, foaming heating rate and sintering temperature. The optimal product was produced with 0.33AMF, foaming at 100 °C/h and sintering at 1600 °C. This product attained high porosity of 94.39%, large average pore size of 300 µm and the highest compressive strength of 384 kPa. To improve bioactivity, doping of porous alumina by soaking in dilute or saturated solutions of Ca, P, Mg, CaP or CaP + Mg was done. Saturated solutions of Ca, P, Mg, CaP and CaP + Mg were made with excess salt in distilled water and decanted. Dilute solutions were made by diluting the 100% solution to 10% concentration. Doping with Si was done using the sol gel method at 100% concentration only. Cell culture was carried out with MG63 osteosarcoma cells. Cellular response to the Si and P doped samples was positive with high cell populations and cell layer formation. The impact of doping with phosphate produced a result not previously reported. The cellular response showed that both Si and P doping improved the biocompatibility of the foamed alumina.

  11. Dynamic deformation and fragmentation response of maraging steel linear cellular alloy

    Science.gov (United States)

    Jakus, Adam E.; Fredenberg, David A.; McCoy, Tammy; Thadhani, Naresh; Cochran, Joe K.

    2012-03-01

    The dynamic deformation and fragmentation response of 25% dense 9-cell linear cellular alloy (LCA) made of unaged 250 maraging steel, fabricated using a direct reduction and extrusion technique, is investigated. Explicit finite element simulations were implemented using AUTODYN finite element code. The maraging steel properties were defined using a Johnson-Cook strength model with previously validated parameters. Rod-on-anvil impact tests were performed using the 7.6mm helium gas gun and the transient deformation and fragmentation response was recorded with highspeed imaging. Analysis of observed deformation states of specimens and finite element simulations reveal that in the case of the 9-cell LCA, dissipation of stress and strain occurs along the interior cell wells resulting in significant and ubiquitous buckling prior to confined fragmentation.

  12. Procyanidins from grape seeds protect against phorbol ester-induced oxidative cellular and genotoxic damage

    Institute of Scientific and Technical Information of China (English)

    Yin LU; Wan-zhou ZHAO; Zai CHANG; Wen-xing CHEN; Lin LI

    2004-01-01

    AIM: To evaluate the inhibitory effects of Vitis vinifera procyanidins (PAs) on carcinogen-induced oxidative stress.METHODS: The single cell gel electrophoresis technique (comet assay) was employed to detect DNA damage induced by the carcinogen phorbol-12-myristate-13-acetate (PMA). The release of hydrogen peroxidase from polymorphonuclear leukocytes (PMNs) was assayed by the horseradish peroxidase-mediated oxidation of phenol red. The microplate assay was used to detect the presence of oxidative products by means of 2',7'-dichlorofiuorescindiacetate (DCFH-DA). The superoxide dismutase (SOD) activity of liver mitochondria was assayed, based on the ability of SOD to inhibit the generation of superoxidate anions by the xanthine-xanthine oxidase system. The malondialdehyde (MDA) level was determined by the thiobarbimric acid (TBA) assay. RESULTS: DNA of NIH3T3 cells was significantly damaged after addition of PMA. The length of the comet tail was observed ,while in normal cells the comet tail could not be observed. PAs showed significant protective effects on carcinogen PMA-induced DNA damage. Through assessment of DCFH-DA oxidation, PAs were shown to inhibit the PMA-induced release of hydrogen peroxide by PMNs, and to inhibit respiratory burst activity in NIH3T3 mouse fibroblasts. Ex vivo study showed that serum from rats administered with PAs displayed similar effects in a dose-dependent manner. In addition, PAs suppressed liver mitochondrial lipid peroxidation induced by PMA. PAs protected the activity of SOD and decreased the level of MDA in liver mitochondria damaged by PMA. CONCLUSION: Dietary PAs from grape seeds protect against carcinogen-induced oxidative cellular and genotoxic damage.

  13. Cellular and molecular responses of E. fetida cœlomocytes exposed to TiO2 nanoparticles

    International Nuclear Information System (INIS)

    An in vitro approach using cœlomocytes of Eisenia fetida was investigated to evaluate toxicity of TiO2 nanoparticles. Cœlomocytes were exposed to well-dispersed suspension of small aggregates (130 nm) of TiO2 nanoparticles (1–25 μg/ml) during 4, 12 and 24 h. Intracellular localisation suggested that the main route of uptake was endocytosis. Cellular responses showed that TiO2 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 μg/ml after 4 h. Superoxide dismutase, catalase and glutathione-S-transferase expression were not modified suggesting that oxidative stress was not induced by TiO2 in our experimental conditions. This in vitro approach showed that TiO2 nanoparticles were taken up by cœlomocytes and they could modify the molecular response of immune and detoxification system.

  14. scFv from Antibody That Mimics gp43 Modulates the Cellular and Humoral Immune Responses during Experimental Paracoccidioidomycosis.

    Directory of Open Access Journals (Sweden)

    Grasielle Pereira Jannuzzi

    Full Text Available Paracoccidioidomycosis (PCM, caused by Paracoccidioides species is a prevalent systemic and progressive mycosis that occurs in Latin America. It is caused by Paracoccidioides species. Immunization with dendritic cells transfected with a plasmid encoding the scFv (pMAC/PS-scFv that mimics the main antigen of P. brasiliensis (gp43 confers protection in experimental PCM. DCs link innate and adaptive immunity by recognizing invading pathogens and selecting the type of effector T cell to mediate the immune response. Here, we showed that DC-pMAC/PS-scFv induces the activation of CD4+ and CD8+ T cells. Moreover, our results demonstrated that BALB/c mice infected with P. brasiliensis and treated with DC-pMAC/PS-scFv showed the induction of specific IgG production against gp43 and IFN-γ, IL-12 and IL-4 cytokines. Analysis of regional lymph nodes revealed increases in the expression of clec7a, myd88, tlr2, gata3 and tbx21, which are involved in the immune response. Taken together, our results indicate that the scFv modulates the humoral and cellular immune responses and presents epitopes to CD4+ and CD8+ T cells.

  15. Cellular responses to HSV-1 infection are linked to specific types of alterations in the host transcriptome.

    Science.gov (United States)

    Hu, Benxia; Li, Xin; Huo, Yongxia; Yu, Yafen; Zhang, Qiuping; Chen, Guijun; Zhang, Yaping; Fraser, Nigel W; Wu, Dongdong; Zhou, Jumin

    2016-01-01

    Pathogen invasion triggers a number of cellular responses and alters the host transcriptome. Here we report that the type of changes to cellular transcriptome is related to the type of cellular functions affected by lytic infection of Herpes Simplex Virus type I in Human primary fibroblasts. Specifically, genes involved in stress responses and nuclear transport exhibited mostly changes in alternative polyadenylation (APA), cell cycle genes showed mostly alternative splicing (AS) changes, while genes in neurogenesis, rarely underwent these changes. Transcriptome wide, the infection resulted in 1,032 cases of AS, 161 incidences of APA, 1,827 events of isoform changes, and up regulation of 596 genes and down regulations of 61 genes compared to uninfected cells. Thus, these findings provided important and specific links between cellular responses to HSV-1 infection and the type of alterations to the host transcriptome, highlighting important roles of RNA processing in virus-host interactions. PMID:27354008

  16. Cellular responses to HSV-1 infection are linked to specific types of alterations in the host transcriptome

    Science.gov (United States)

    Hu, Benxia; Li, Xin; Huo, Yongxia; Yu, Yafen; Zhang, Qiuping; Chen, Guijun; Zhang, Yaping; Fraser, Nigel W.; Wu, Dongdong; Zhou, Jumin

    2016-01-01

    Pathogen invasion triggers a number of cellular responses and alters the host transcriptome. Here we report that the type of changes to cellular transcriptome is related to the type of cellular functions affected by lytic infection of Herpes Simplex Virus type I in Human primary fibroblasts. Specifically, genes involved in stress responses and nuclear transport exhibited mostly changes in alternative polyadenylation (APA), cell cycle genes showed mostly alternative splicing (AS) changes, while genes in neurogenesis, rarely underwent these changes. Transcriptome wide, the infection resulted in 1,032 cases of AS, 161 incidences of APA, 1,827 events of isoform changes, and up regulation of 596 genes and down regulations of 61 genes compared to uninfected cells. Thus, these findings provided important and specific links between cellular responses to HSV-1 infection and the type of alterations to the host transcriptome, highlighting important roles of RNA processing in virus-host interactions. PMID:27354008

  17. Cellular gene expression induced by parasite antigens and allergens in neonates from parasite-infected mothers.

    Science.gov (United States)

    Soboslay, Peter T; Orlikowsky, Thorsten; Huang, Xiangsheng; Gille, Christian; Spring, Bärbel; Kocherscheidt, Lars; Agossou, Abram; Banla, Meba; Bonin, Michael; Köhler, Carsten

    2016-05-01

    Prenatal exposure to parasite antigens or allergens will influence the profile and strength of postnatal immune responses, such contact may tolerize and increase susceptibility to future infections or sensitize to environmental allergens. Exposure in utero to parasite antigens will distinctly alter cellular gene expression in newborns. Gene microarrays were applied to study gene expression in umbilical cord blood cell (UCBC) from parasite-exposed (Para-POS) and non-exposed (Para-NEG) neonates. UCBC were activated with antigens of helminth (Onchocerca volvulus), amoeba (Entamoeba histolytica) or allergens of mite (Dermatophagoides farinae). When UCBC from Para-POS and Para-NEG newborns were exposed to helminth antigens or allergens consistent differences occurred in the expression of genes encoding for MHC class I and II alleles, signal transducers of activation and transcription (STATs), cytokines, chemokines, immunoglobulin heavy and light chains, and molecules associated with immune regulation (SOCS, TLR, TGF), inflammation (TNF, CCR) and apoptosis (CASP). Expression of genes associated with innate immune responses were enhanced in Para-NEG, while in Para-POS, the expression of MHC class II and STAT genes was reduced. Within functional gene networks for cellular growth, proliferation and immune responses, Para-NEG neonates presented with significantly higher expression values than Para-POS. In Para-NEG newborns, the gene cluster and pathway analyses suggested that gene expression profiles may predispose for the development of immunological, hematological and dermatological disorders upon postnatal helminth parasite infection or allergen exposure. Thus, prenatal parasite contact will sensitize without generating aberrant inflammatory immune responses, and increased pro-inflammatory but decreased regulatory gene expression profiles will be present in those neonates lacking prenatal parasite antigen encounter. PMID:27062712

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

    OpenAIRE

    Akiyoshi Taniguchi; Koki Kanehira; Sharmy Saimon Mano

    2013-01-01

    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 o...

  19. Fluorescent cDNA microarray hybridization reveals complexity and heterogeneity of cellular genotoxic stress responses.

    Science.gov (United States)

    Amundson, S A; Bittner, M; Chen, Y; Trent, J; Meltzer, P; Fornace, A J

    1999-06-17

    The fate of cells exposed to ionizing radiation (IR) may depend greatly on changes in gene expression, so that an improved view of gene induction profiles is important for understanding mechanisms of checkpoint control, repair and cell death following such exposures. We have used a quantitative fluorescent cDNA microarray hybridization approach to identify genes regulated in response to 7-irradiation in the p53 wild-type ML-1 human myeloid cell line. Hybridization of the array to fluorescently-labeled RNA from treated and untreated cells was followed by computer analysis to derive relative changes in expression levels of the genes present in the array, which agreed well with actual quantitative changes in expression. Forty-eight sequences, 30 not previously identified as IR-responsive, were significantly regulated by IR. Induction by IR and other stresses of a subset of these genes, including the previously characterized CIP1/ WAF1, MDM2 and BAX genes, as well as nine genes not previously reported to be IR-responsive, was examined in a panel of 12 human cell lines. Responses varied widely in cell lines with different tissues of origin and different genetic backgrounds, highlighting the importance of cellular context to genotoxic stress responses. Two of the newly identified IR-responsive genes, FRA-1 and ATF3, showed a p53-associated component to their IR-induction, and this was confirmed both in isogenic human cell lines and in mouse thymus. The majority of the IR-responsive genes, however, showed no indication of p53-dependent regulation, representing a potentially important class of stress-responsive genes in leukemic cells. PMID:10380890

  20. A cellular model to study drug-induced liver injury in nonalcoholic fatty liver disease: Application to acetaminophen.

    Science.gov (United States)

    Michaut, Anaïs; Le Guillou, Dounia; Moreau, Caroline; Bucher, Simon; McGill, Mitchell R; Martinais, Sophie; Gicquel, Thomas; Morel, Isabelle; Robin, Marie-Anne; Jaeschke, Hartmut; Fromenty, Bernard

    2016-02-01

    Obesity and nonalcoholic fatty liver disease (NAFLD) can increase susceptibility to hepatotoxicity induced by some xenobiotics including drugs, but the involved mechanisms are poorly understood. For acetaminophen (APAP), a role of hepatic cytochrome P450 2E1 (CYP2E1) is suspected since the activity of this enzyme is consistently enhanced during NAFLD. The first aim of our study was to set up a cellular model of NAFLD characterized not only by triglyceride accumulation but also by higher CYP2E1 activity. To this end, human HepaRG cells were incubated for one week with stearic acid or oleic acid, in the presence of different concentrations of insulin. Although cellular triglycerides and the expression of lipid-responsive genes were similar with both fatty acids, CYP2E1 activity was significantly increased only by stearic acid. CYP2E1 activity was reduced by insulin and this effect was reproduced in cultured primary human hepatocytes. Next, APAP cytotoxicity was assessed in HepaRG cells with or without lipid accretion and CYP2E1 induction. Experiments with a large range of APAP concentrations showed that the loss of ATP and glutathione was almost always greater in the presence of stearic acid. In cells pretreated with the CYP2E1 inhibitor chlormethiazole, recovery of ATP was significantly higher in the presence of stearate with low (2.5mM) or high (20mM) concentrations of APAP. Levels of APAP-glucuronide were significantly enhanced by insulin. Hence, HepaRG cells can be used as a valuable model of NAFLD to unveil important metabolic and hormonal factors which can increase susceptibility to drug-induced hepatotoxicity. PMID:26739624

  1. Nanoparticle-allergen interactions mediate human allergic responses: protein corona characterization and cellular responses

    OpenAIRE

    Radauer-Preiml, Isabella; Andosch, Ancuela; Hawranek, Thomas; Luetz-Meindl, Ursula; Wiederstein, Markus; Horejs-Hoeck, Jutta; Himly, Martin; Boyles, Matthew; Duschl, Albert

    2016-01-01

    Background Engineered nanomaterials (ENMs) interact with different biomolecules as soon as they are in contact, resulting in the formation of a biomolecule ‘corona’. Hence, the ‘corona’ defines the biological identity of the ENMs and could affect the response of the immune system to ENM exposure. With up to 40 % of the world population suffering from type I allergy, a possible modulation of allergen effects by binding to ENMs is highly relevant with respect to work place and consumer safety. ...

  2. Microscopic studies of cellular damage induced by compression waves in different environments

    Science.gov (United States)

    Bo, Chiara; Balzer, Jens; Brown, Katherine A.; Proud, William G.

    2011-06-01

    The cellular basis of induced-damage in biological samples under dynamic loading conditions is largely uncharacterized. In this study we propose a new approach to investigate the effects of compression waves on in-vitro grown Stem cells extracted from BALB/c mice. A modified split Hopkinson pressure bar system is used to simulate damage in the biological samples: the cells are inserted in a confinement chamber either in their growing media or on a 3D scaffold, they are subjected to compression waves and finally recovered for further analysis. The difference in mechanical impedance between the cells and the hosting environments is believed to be a key point in the generation of damage. To discriminate the effects of the different mechanical supports on cell morphology pre and after compression, membrane and cytoskeletal proteins disruptions are investigated using fluorescence confocal microscopy. Understanding the underlying mechanism of damage at the microscopic scale could set the basis for the development of therapeutic applications at the cellular level.

  3. Fungicidal Drugs Induce a Common Oxidative-Damage Cellular Death Pathway

    Directory of Open Access Journals (Sweden)

    Peter Belenky

    2013-02-01

    Full Text Available Amphotericin, miconazole, and ciclopirox are antifungal agents from three different drug classes that can effectively kill planktonic yeast, yet their complete fungicidal mechanisms are not fully understood. Here, we employ a systems biology approach to identify a common oxidative-damage cellular death pathway triggered by these representative fungicides in Candida albicans and Saccharomyces cerevisiae. This mechanism utilizes a signaling cascade involving the GTPases Ras1 and Ras2 and protein kinase A, and it culminates in death through the production of toxic reactive oxygen species in a tricarboxylic-acid-cycle- and respiratory-chain-dependent manner. We also show that the metabolome of C. albicans is altered by antifungal drug treatment, exhibiting a shift from fermentation to respiration, a jump in the AMP/ATP ratio, and elevated production of sugars; this coincides with elevated mitochondrial activity. Lastly, we demonstrate that DNA damage plays a critical role in antifungal-induced cellular death and that blocking DNA-repair mechanisms potentiates fungicidal activity.

  4. Cellular cooperation during in vivo anti-hapten antibody responses. I. The effect of cell number on the response

    International Nuclear Information System (INIS)

    Cellular interactions in adoptive secondary anti-hapten antibody responses to the hapten 2,4-dinitrophenyl (DNP) have been studied. It was shown that DNP-specific B cells must interact with carrier specific helper T cells to give optimal responses. Independent titration of B cell and helper cell activity in adoptive anti-DNP antibody responses gave the following results: Doubling the number of transferred B cells approximately doubled the subsequent antibody response. Doubling the number of helper cells leads to nearly 4 times as much anti-DNP antibody, measured 7 days after boosting (''premium effect''). This marked effect of helper cell number on the antibody response is thought to be due primarily to the interaction of two populations of carrier-specific cells in the helper effect, or to the interaction of two activities of a single population of helper cells, namely clone activation and clone expansion. Only a very small proportion of the premium effect given by helper cells could be attributed to increases in antibody affinity. (U.S.)

  5. Gymnemagenin-a triterpene saponin prevents γ-radiation induced cellular DNA damage

    International Nuclear Information System (INIS)

    Gymnema sylvestre an ethno-medicinally important plant was investigated for its protecting activity against radiation induced DNA damage. The major bioactive component present in Gymnema sylvestre such as gymnemic acid and gymnemagenin a triterpene saponin, were tested for its radioprotective effects against 60Co irradiation induced DNA damage in fish model using fresh water fish Pangasius sutchi. Fishes subjected to a dose of 133 Gy of gamma radiation and observed for eight days. The genotoxic assessment by micronucleus assay showed us that that the plant extract helped in reducing the frequency of micronucleated and binucleated erythrocytes compared to the irradiated control group. The genotoxic assessment by alkaline comet assay by single gel electrophoresis shows that pretreatment with the plant extract appreciably decreased the percentage of tail DNA towards the levels close to those of normal control group. The gradual increase in the level of the antioxidant enzymes: superoxide dismutase (SOD) and catalase (CAT) during the course of the experiment indicates that the antioxidant enzyme activities play an important role in protecting organisms against gamma radiation-induced cellular oxidative stress. In conclusion the leaf extracts of Gymnema sylvstre exerts its radio protective potential by suppressing the toxic assault of ROS generated by the ionizing radiation through its ability to boost the levels of antioxidant enzymes (CAT and SOD) due to the presence of its phytochemicals like gymnemgenenin- a Triterpene Saponin. (author)

  6. Drinking induced by cellular dehydration in the quail, Coturnix coturnix japonica.

    Science.gov (United States)

    Takei, Y; Okawara, Y; Kobayashi, H

    1988-01-01

    1. Drinking was induced in water-replete quail 5-10 min after intravenous injection of hypertonic NaCl (0.69 osmol/l) or sucrose (1.06 osmol/l), but hypertonic urea (2.78 osmol/l) failed to induce drinking. 2. The birds drank approximately the amount required to dilute the injected solutes to isotonicity for each given dose of NaCl or sucrose. 3. The plasma angiotensin II level decreased after injection of 7% NaCl (2.5 osmol/l), but it increased after injection of an equi-osmolar solution of sucrose (65%). 4. Plasma osmolality and Na+ concentration returned quickly to control levels, and then decreased further, after injection of 7% NaCl or 65% sucrose. 5. Blood volume and blood pressure increased immediately after injection of 7% NaCl or 65% sucrose. 6. These results show that drinking is induced after injection of hypertonic solutions exclusively by cellular dehydration, and other regulatory mechanisms for thirst, such as extracellular dehydration and the renin-angiotensin system, are rather inhibitory after injection of hypertonic NaCl. PMID:2900120

  7. Dynamics of uptake and metabolism of small molecules in cellular response systems.

    Directory of Open Access Journals (Sweden)

    Maria Werner

    Full Text Available BACKGROUND: Proper cellular function requires uptake of small molecules from the environment. In response to changes in extracellular conditions cells alter the import and utilization of small molecules. For a wide variety of small molecules the cellular response is regulated by a network motif that combines two feedback loops, one which regulates the transport and the other which regulates the subsequent metabolism. RESULTS: We analyze the dynamic behavior of two widespread but logically distinct two-loop motifs. These motifs differ in the logic of the feedback loop regulating the uptake of the small molecule. Our aim is to examine the qualitative features of the dynamics of these two classes of feedback motifs. We find that the negative feedback to transport is accompanied by overshoot in the intracellular amount of small molecules, whereas a positive feedback to transport removes overshoot by boosting the final steady state level. On the other hand, the negative feedback allows for a rapid initial response, whereas the positive feedback is slower. We also illustrate how the dynamical deficiencies of one feedback motif can be mitigated by an additional loop, while maintaining the original steady-state properties. CONCLUSIONS: Our analysis emphasizes the core of the regulation found in many motifs at the interface between the metabolic network and the environment of the cell. By simplifying the regulation into uptake and the first metabolic step, we provide a basis for elaborate studies of more realistic network structures. Particularly, this theoretical analysis predicts that FeS cluster formation plays an important role in the dynamics of iron homeostasis.

  8. Continuous cellularization of calcium phosphate hybrid scaffolds induced by plasma polymer activation.

    Science.gov (United States)

    Bergemann, Claudia; Cornelsen, Matthias; Quade, Antje; Laube, Thorsten; Schnabelrauch, Matthias; Rebl, Henrike; Weißmann, Volker; Seitz, Hermann; Nebe, Barbara

    2016-02-01

    The generation of hybrid materials based on β-tricalcium phosphate (TCP) and various biodegradable polymers like poly(l-lactide-co-d,l-lactide) (PLA) represents a common approach to overcoming the disadvantages of pure TCP devices. These disadvantages lie in TCP's mechanical properties, such as brittleness. The positive characteristic of PLA - improvement of compressive strength of calcium phosphate scaffolds - is diametrically opposed to its cell attractiveness. Therefore, the objective of this work was to optimize osteoblast migration and cellularization inside a three-dimensionally (3D) printed, PLA polymer stabilized TCP hybrid scaffold by a plasma polymer process depositing amino groups via allylamine. MG-63 osteoblastic cells inside the 10mm hybrid scaffold were dynamically cultivated for 14days in a 3D model system integrated in a perfusion reactor. The whole TCP/PLA hybrid scaffold was continuously colonized due to plasma polymerized allylamine activation inducing the migration potential of osteoblasts. PMID:26652403

  9. Cellular Changes during Renal Failure-Induced Inflammatory Aortic Valve Disease

    Science.gov (United States)

    Mustafa, Mahmoud; Duvdevan, Nitsan; Meir, Karen; Beeri, Ronen; Lotan, Chaim

    2015-01-01

    Background Aortic valve calcification (AVC) secondary to renal failure (RF) is an inflammation-regulated process, but its pathogenesis remains unknown. We sought to assess the cellular processes that are involved in the early phases of aortic valve disease using a unique animal model of RF-associated AVC. Methods Aortic valves were obtained from rats that were fed a uremia-inducing diet exclusively for 2, 3, 4, 5, and 6 weeks as well as from controls. Pathological examination of the valves included histological characterization, von Kossa staining, and antigen expression analyses. Results After 2 weeks, we noted a significant increase in urea and creatinine levels, reflecting RF. RF parameters exacerbated until the Week 5 and plateaued. Whereas no histological changes or calcification was observed in the valves of any study group, macrophage accumulation became apparent as early as 2 weeks after the diet was started and rose after 3 weeks. By western blot, osteoblast markers were expressed after 2 weeks on the diet and decreased after 6 weeks. Collagen 3 was up-regulated after 3 weeks, plateauing at 4 weeks, whereas collagen 1 levels peaked at 2 and 4 weeks. Fibronectin levels increased gradually until Week 5 and decreased at 6 weeks. We observed early activation of the ERK pathway, whereas other pathways remained unchanged. Conclusions We concluded that RF induces dramatic changes at the cellular level, including macrophage accumulation, activation of cell signaling pathway and extracellular matrix modification. These changes precede valve calcification and may increase propensity for calcification, and have to be investigated further. PMID:26070132

  10. Cellular mechanisms of tissue fibrosis. 6. Purinergic signaling and response in fibroblasts and tissue fibrosis.

    Science.gov (United States)

    Lu, David; Insel, Paul A

    2014-05-01

    Tissue fibrosis occurs as a result of the dysregulation of extracellular matrix (ECM) synthesis. Tissue fibroblasts, resident cells responsible for the synthesis and turnover of ECM, are regulated via numerous hormonal and mechanical signals. The release of intracellular nucleotides and their resultant autocrine/paracrine signaling have been shown to play key roles in the homeostatic maintenance of tissue remodeling and in fibrotic response post-injury. Extracellular nucleotides signal through P2 nucleotide and P1 adenosine receptors to activate signaling networks that regulate the proliferation and activity of fibroblasts, which, in turn, influence tissue structure and pathologic remodeling. An important component in the signaling and functional responses of fibroblasts to extracellular ATP and adenosine is the expression and activity of ectonucleotideases that attenuate nucleotide-mediated signaling, and thereby integrate P2 receptor- and subsequent adenosine receptor-initiated responses. Results of studies of the mechanisms of cellular nucleotide release and the effects of this autocrine/paracrine signaling axis on fibroblast-to-myofibroblast conversion and the fibrotic phenotype have advanced understanding of tissue remodeling and fibrosis. This review summarizes recent findings related to purinergic signaling in the regulation of fibroblasts and the development of tissue fibrosis in the heart, lungs, liver, and kidney. PMID:24352335

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

    International Nuclear Information System (INIS)

    Highlights: • LPA5 inhibits the cell growth and motile activities of 3T3 cells. • LPA5 suppresses the cell motile activities stimulated by hydrogen peroxide in 3T3 cells. • Enhancement of LPA5 on the cell motile activities inhibited by LPA1 in 3T3 cells. • The expression and activation of Mmp-9 were inhibited by LPA5 in 3T3 cells. • LPA signaling via LPA5 acts as a negative regulator of cellular responses in 3T3 cells. - Abstract: Lysophosphatidic acid (LPA) signaling via G protein-coupled LPA receptors (LPA1–LPA6) mediates a variety of biological functions, including cell migration. Recently, we have reported that LPA1 inhibited the cell motile activities of mouse fibroblast 3T3 cells. In the present study, to evaluate a role of LPA5 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 LPA1 and LPA5 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 LPA5 may act as a negative regulator of cellular responses in mouse fibroblast 3T3 cells, similar to the case for LPA1

  12. 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}.

  13. 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.

  14. Early cellular immune response to a new candidate mycobacterial vaccine antigen in childhood tuberculosis.

    Science.gov (United States)

    Schepers, K; Dirix, V; Mouchet, F; Verscheure, V; Lecher, S; Locht, C; Mascart, F

    2015-02-18

    The search for novel vaccines against tuberculosis (TB) would benefit from in-depths knowledge of the human immune responses to Mycobacterium tuberculosis (Mtb) infection. Here, we characterised in a low TB incidence country, the immune responses to a new candidate vaccine antigen against TB, the heparin-binding haemagglutinin (HBHA), in young children in contact with an active TB case (aTB). Children with no history of BCG vaccination were compared to those vaccinated at birth to compare the initial immune responses to HBHA with secondary immune responses. Fifty-eight children with aTB and 76 with latent TB infection (LTBI) were included and they were compared to 90 non-infected children. Whereas Mtb-infected children globally secreted more interferon-gamma (IFN-γ) in response to HBHA compared to the non-infected children, these IFN-γ concentrations were higher in previously BCG-vaccinated compared to non-vaccinated children. The IFN-γ concentrations were similar in LTBI and aTB children, but appeared to differ qualitatively. Whereas the IFN-γ secretion induced by native methylated and recombinant non-methylated HBHA were well correlated for aTB, this was not the case for LTBI children. Thus, Mtb-infected young children develop IFN-γ responses to HBHA that are enhanced by prior BCG vaccination, indicating BCG-induced priming, thereby supporting a prime-boost strategy for HBHA-based vaccines. The qualitative differences between aTB and LTBI in their HBHA-induced IFN-γ responses may perhaps be exploited for diagnostic purposes. PMID:25583385

  15. Epstein-Barr virus BGLF4 kinase retards cellular S-phase progression and induces chromosomal abnormality.

    Directory of Open Access Journals (Sweden)

    Yu-Hsin Chang

    Full Text Available Epstein-Barr virus (EBV induces an uncoordinated S-phase-like cellular environment coupled with multiple prophase-like events in cells replicating the virus. The EBV encoded Ser/Thr kinase BGLF4 has been shown to induce premature chromosome condensation through activation of condensin and topoisomerase II and reorganization of the nuclear lamina to facilitate the nuclear egress of nucleocapsids in a pathway mimicking Cdk1. However, the observation that RB is hyperphosphorylated in the presence of BGLF4 raised the possibility that BGLF4 may have a Cdk2-like activity to promote S-phase progression. Here, we investigated the regulatory effects of BGLF4 on cell cycle progression and found that S-phase progression and DNA synthesis were interrupted by BGLF4 in mammalian cells. Expression of BGLF4 did not compensate Cdk1 defects for DNA replication in S. cerevisiae. Using time-lapse microscopy, we found the fate of individual HeLa cells was determined by the expression level of BGLF4. In addition to slight cell growth retardation, BGLF4 elicits abnormal chromosomal structure and micronucleus formation in 293 and NCP-TW01 cells. In Saos-2 cells, BGLF4 induced the hyperphosphorylation of co-transfected RB, while E2F1 was not released from RB-E2F1 complexes. The E2F1 regulated activities of the cyclin D1 and ZBRK1 promoters were suppressed by BGLF4 in a dose dependent manner. Detection with phosphoamino acid specific antibodies revealed that, in addition to Ser780, phosphorylation of the DNA damage-responsive Ser612 on RB was enhanced by BGLF4. Taken together, our study indicates that BGLF4 may directly or indirectly induce a DNA damage signal that eventually interferes with host DNA synthesis and delays S-phase progression.

  16. Gestational zinc deficiency impairs humoral and cellular immune responses to hepatitis B vaccination in offspring mice.

    Directory of Open Access Journals (Sweden)

    Ning Zhao

    Full Text Available BACKGROUND: Gestational zinc deficiency has been confirmed to impair the infant immune function. However, knowledge about effects of maternal mild zinc deficiency during pregnancy on hepatitis B vaccine responsiveness in offspring is limited. In this report, we aimed to examine how maternal zinc deficiency during pregnancy influences humoral and cellular immune responses to hepatitis B vaccination in offspring of BALB/c mice. METHODOLOGY/PRINCIPAL FINDINGS: From day 1 of pregnancy upon delivery, maternal mice were given a standard diet (30 mg/kg/day zinc, zinc deficient diet (8 mg/kg/day zinc, or combination of zinc deficient diet (8 mg/kg/day zinc in the first 2 weeks of gestation and zinc supplement diet (150 mg/kg/day zinc for the last week of pregnancy, respectively. Newborn pups of these maternal mice were immunized with hepatitis B vaccine at postnatal weeks 0, 2 and 4. Then, splenocytes and blood samples from the offspring mice were harvested for detection of serum zinc concentrations, humoral and cell-mediated immune responses, expression of cytokines using ELISA, CCK-8 and flow cytometric analysis. Results from the present study demonstrated that gestational zinc deficiency inhibited antibody responses, and decreased the proliferative capacity of T cells in offsprings immunized with hepatitis B vaccine. Additionally, HBsAg-specific cytokines analysis revealed that gestational zinc deficiency could inhibit secretion of IFN-γ from splenocytes, and decrease IFN-γ expression of CD4(+ and CD8(+ T cells. CONCLUSIONS/SIGNIFICANCE: Gestational zinc deficiency can weaken the humoral and cell-mediated immune responses to hepatitis B vaccine via decreasing B cell counts and hepatitis B virus-specific immunoglobulin G production, as well as reducing T cell proliferation, CD4(+/CD8(+ T cell ratio, and Th1-type immune responses.

  17. Resveratrol induces cellular senescence with attenuated mono-ubiquitination of histone H2B in glioma cells

    International Nuclear Information System (INIS)

    Research highlights: → Resveratrol induces cellular senescence in glioma cell. → Resveratrol inhibits mono-ubiquitination of histone H2B at K120. → Depletion of RNF20, phenocopies the inhibitory effects of resveratrol. → Mono-ubiquitination of histone H2B at K120 is a novel target of resveratrol. → RNF20 inhibits cellular senescence in proliferating glioma cells. -- Abstract: Resveratrol (3,4',5-trihydroxy-trans-stilbene), a polyphenol naturally occurring in grapes and other plants, has cancer chemo-preventive effects and therapeutic potential. Although resveratrol modulates multiple pathways in tumor cells, how resveratrol or its affected pathways converge on chromatin to mediate its effects is not known. Using glioma cells as a model, we showed here that resveratrol inhibited cell proliferation and induced cellular hypertrophy by transforming spindle-shaped cells to enlarged, irregular and flatten-shaped ones. We further showed that resveratrol-induced hypertrophic cells expressed senescence-associated-β-galactosidase, suggesting that resveratrol-induced cellular senescence in glioma cells. Consistent with these observations, we demonstrated that resveratrol inhibited clonogenic efficiencies in vitro and tumor growth in a xenograft model. Furthermore, we found that acute treatment of resveratrol inhibited mono-ubiquitination of histone H2B at K120 (uH2B) in breast, prostate, pancreatic, lung, brain tumor cells as well as primary human cells. Chronic treatment with low doses of resveratrol also inhibited uH2B in the resveratrol-induced senescent glioma cells. Moreover, we showed that depletion of RNF20, a ubiquitin ligase of histone H2B, inhibited uH2B and induced cellular senescence in glioma cells in vitro, thereby recapitulated the effects of resveratrol. Taken together, our results suggest that uH2B is a novel direct or indirect chromatin target of resveratrol and RNF20 plays an important role in inhibiting cellular senescence programs that are

  18. Increased cellular proliferation in rat skeletal muscle and tendon in response to exercise: use of FLT and PET/CT

    DEFF Research Database (Denmark)

    Skovgaard, Dorthe Charlotte; Bayer, Monika L; Mackey, Abigail L;

    2010-01-01

    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.......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....

  19. Computer simulation of a cellular automata model for the immune response in a retrovirus system

    International Nuclear Information System (INIS)

    Immune response in a retrovirus system is modeled by a network of three binary cell elements to take into account some of the main functional features of T4 cells, T8 cells, and viruses. Two different intercell interactions are introduced, one of which leads to three fixed points while the other yields bistable fixed points oscillating between a healthy state and a sick state in a mean field treatment. Evolution of these cells is studied for quenched and annealed random interactions on a simple cubic lattice with a nearest neighbor interaction using inhomogenous cellular automata. Populations of T4 cells and viral cells oscillate together with damping (with constant amplitude) for annealed (quenched) interaction on increasing the value of mixing probability B from zero to a characteristic value Bca (Bcq). For higher B, the average number of T4 cells increases while that of the viral infected cells decreases monotonically on increasing B, suggesting a phase transition at Bca (Bcq)

  20. Unraveling the cellular response to oxidative stress in the endoplasmic reticulum

    DEFF Research Database (Denmark)

    Hansen, Henning Gram

    , disulfide bonds are predominantly generated by the two isoforms of the ER oxidoreductin-1 (Ero1) family: Ero1α and Ero1β. Both enzymes oxidize the active-site cysteines in protein disulfide isomerases (PDIs), which in turn introduce disulfide bonds into newly synthesized proteins. Ero1 is re......-oxidized by molecular oxygen and this step generates hydrogen peroxide: a reactive oxygen species. Intramolecular disulfide bonds tightly regulate the oxidase activity of Ero1α. Whereas the regulatory mechanisms that regulate Ero1α activity are well understood, the overall cellular response to oxidative stress...... that these enzymes are PDI peroxidases and may comprise an as yet unidentified pathway for disulfide bond formation in cells. However, the results presented here indicate that GPx7 and GPx8 do not comprise a major pathway for disulfide bond formation in the ER in cells deficient in Ero1 and peroxiredoxin-4...

  1. Mechanisms of protective immunity against Schistosoma mansoni infection in mice vaccinated with irradiated cercariae. V. Anamnestic cellular and humoral responses following challenge infection

    Energy Technology Data Exchange (ETDEWEB)

    Correa-Oliveira, R.; Sher, A.; James, S.L.

    1984-03-01

    Mice vaccinated with radiation-attenuated cercariae display low levels of cellular and humoral immune responses toward schistosomulum antigens, as measured in vitro by lymphocyte blastogenesis and quantitation of anti-larval antibodies by indirect immunofluorescence. Both responses wane with time after vaccination. However subsequent challenge infection provokes immune responses of classical anamnestic character, being both more rapid in appearance and of greater magnitude. Antigen responsive cells appear in lymph nodes draining the challenge site within 24 hours after infection. Both circulating anti-schistosomulum surface antibodies as well as cytophilic IgE anti-worm antigen antibodies increase substantially by 1 week after challenge. All of the anamnestic circulating antibodies belong to the IgG class. Those findings support the concept that vaccine-induced resistance to Schistosoma mansoni infection involves sensitized T and B lymphocytes, and point to the possible role of post-challenge anamnestic responses in the effector mechanism of parasite killing in this model.

  2. Mechanisms of protective immunity against Schistosoma mansoni infection in mice vaccinated with irradiated cercariae. V. Anamnestic cellular and humoral responses following challenge infection

    International Nuclear Information System (INIS)

    Mice vaccinated with radiation-attenuated cercariae display low levels of cellular and humoral immune responses toward schistosomulum antigens, as measured in vitro by lymphocyte blastogenesis and quantitation of anti-larval antibodies by indirect immunofluorescence. Both responses wane with time after vaccination. However subsequent challenge infection provokes immune responses of classical anamnestic character, being both more rapid in appearance and of greater magnitude. Antigen responsive cells appear in lymph nodes draining the challenge site within 24 hours after infection. Both circulating anti-schistosomulum surface antibodies as well as cytophilic IgE anti-worm antigen antibodies increase substantially by 1 week after challenge. All of the anamnestic circulating antibodies belong to the IgG class. Those findings support the concept that vaccine-induced resistance to Schistosoma mansoni infection involves sensitized T and B lymphocytes, and point to the possible role of post-challenge anamnestic responses in the effector mechanism of parasite killing in this model

  3. Humoral and cellular response to BoHV-1 in buffalo and cattle treated with an inactivated marker vaccine

    Directory of Open Access Journals (Sweden)

    A. Marocchi

    2010-02-01

    Full Text Available The study is aimed at assessing and comparing the immune response to BoHV-1 elicited by an inactivated marker vaccine in buffaloes and cattle. Vaccination did not produced any local or general reactions in buffaloes. Seroneutralizing antibodies and cellular response by IFN-γ- test have been detected in buffaloes and cattle after a prime/ booster vaccination strategy. Humoral and cellular responses were significantly higher in cattle than in buffaloes. Data pointed out the possibility to use the marker vaccine in buffaloes. However, further studies must be planned to assess the immune pressure of marker vaccines in terms of IBR eradicative attitude in infected buffalo herds.

  4. 3D scaffold alters cellular response to graphene in a polymer composite for orthopedic applications.

    Science.gov (United States)

    Kumar, Sachin; Azam, Dilkash; Raj, Shammy; Kolanthai, Elayaraja; Vasu, K S; Sood, A K; Chatterjee, Kaushik

    2016-05-01

    Graphene-based polymer nanocomposites are being studied for biomedical applications. Polymer nanocomposites can be processed differently to generate planar two-dimensional (2D) substrates and porous three-dimensional (3D) scaffolds. The objective of this work was to investigate potential differences in biological response to graphene in polymer composites in the form of 2D substrates and 3D scaffolds. Polycaprolactone (PCL) nanocomposites were prepared by incorporating 1% of graphene oxide (GO) and reduced graphene oxide (RGO). GO increased modulus and strength of PCL by 44 and 22% respectively, whereas RGO increased modulus and strength by 22 and 16%, respectively. RGO increased the water contact angle of PCL from 81° to 87° whereas GO decreased it to 77°. In 2D, osteoblast proliferated 15% more on GO composites than on PCL whereas RGO composite showed 17% decrease in cell proliferation, which may be attributed to differences in water wettability. In 3D, initial cell proliferation was markedly retarded in both GO (36% lower) and RGO (55% lower) composites owing to increased roughness due to the presence of the protruding nanoparticles. Cells organized into aggregates in 3D in contrast to spread and randomly distributed cells on 2D discs due to the macro-porous architecture of the scaffolds. Increased cell-cell contact and altered cellular morphology led to significantly higher mineralization in 3D. This study demonstrates that the cellular response to nanoparticles in composites can change markedly by varying the processing route and has implications for designing orthopedic implants such as resorbable fracture fixation devices and tissue scaffolds using such nanocomposites. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 732-749, 2016. PMID:26482196

  5. 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. PMID:25621396

  6. Cellular responses to 836 MHz and 1,765 GHz CDMA radiations

    International Nuclear Information System (INIS)

    The effect of radiofrequency (RF) radiation in the cellular phone communication range (836.5 MHz and 1.765 GHz code division multiple access, CDMA) on tumorigenesis and other health effect was measured using the in vitro cell culture system. To determine whether 836.5 MHz or 1.765 GHz CDMA radiations have any genotoxic effects to induce neoplastic transformation, C3H 10T1/2 cells were exposed to either of the above radiations at a specific absorption rate (SAR) of 35.6W/Kg (836.5 MHz) and 38.2 W/kg(1.765 GHz) or sham- exposed at the same time for 7 days. Cells were maintained in incubators and refed with fresh growth medium every 3 days. At this SAR, radiofrequency radiation did not induce neoplastic transformation in vitro. The extent of alteration in the kinetics of cell proliferation indicated no significant differences between RF-radiation- and sham-exposed cells with respect to MTS assay and 8-OHdG. Under this experimental conditions tested, there is no evidence for the induction of genotoxic indices in human and mouse cells exposed in vitro for 7 days to 836.5 MHz or 1.765 GHz RF radiation at SARs of up to 35.6 or 38.2 W/kg

  7. Nuclear and cytoplasmic signalling in the cellular response to ionising radiation

    International Nuclear Information System (INIS)

    DNA is the universal primary target for ionising radiation; however, the cellular response is highly diversified not only by differential DNA repair ability. The monitoring system for the ionising radiation-inflicted DNA damage consists of 3 apparently independently acting enzymes which are activated by DNA breaks: two protein kinases, ATM (ataxia telangiectasia mutated) and DNA-PK (DNA-dependent protein kinase) and a poly(ADP-ribose) polymerase, PARP-1. These 3 enzymes are the source of alarm signals, which affect to various extents DNA repair, progression through the cell cycle and eventually the pathway to cell death. Their functions probably are partly overlapping. On the side of DNA repair their role consists in recruiting and/or activating the repair enzymes, as well as preventing illegitimate recombination of the damaged sites. A large part of the nuclear signalling pathway, including the integrating role of TP53 has been revealed. Two main signalling pathways start at the plasma membrane: the MAPK/ERK (mitogen and extracellular signal regulated protein kinase family) 'survival pathway' and the SAPK/JNK (stress-activated protein kinase/c-Jun N-terminal kinase) 'cell death pathway'. The balance between them is likely to determine the cell's fate. An additional important 'survival pathway' starts at the insulin-like growth factor type I receptor (IGF-IR), involves phosphoinositide- 3 kinase and Akt kinase and is targeted at inactivation of the pro-apoptotic BAD protein. Interestingly, over-expression of IGF-IR almost entirely abrogates the extreme radiation sensitivity of ataxia telangiectasia cells. When DNA break rejoining is impaired, the cell is unconditionally radiation sensitive. The fate of a repair-competent cell is determined by the time factor: the cell cycle arrest should be long enough to ensure the completion of repair. Incomplete repair or misrepair may be tolerated, when generation of the death signal is prevented. So, the character and timing

  8. 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.

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

    Science.gov (United States)

    Chen, Peng; Kanehira, Koki; Taniguchi, Akiyoshi

    2013-02-01

    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.

  10. 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.

  11. No evident dose-response relationship between cellular ROS level and its cytotoxicity--a paradoxical issue in ROS-based cancer therapy.

    Science.gov (United States)

    Zhu, Chunpeng; Hu, Wei; Wu, Hao; Hu, Xun

    2014-01-01

    Targeting cancer via ROS-based mechanism has been proposed as a radical therapeutic approach. Cancer cells exhibit higher endogenous oxidative stress than normal cells and pharmacological ROS insults via either enhancing ROS production or inhibiting ROS-scavenging activity can selectively kill cancer cells. In this study, we randomly chose 4 cancer cell lines and primary colon or rectal cancer cells from 4 patients to test the hypothesis and obtained following paradoxical results: while piperlongumin (PL) and β-phenylethyl isothiocyanate (PEITC), 2 well-defined ROS-based anticancer agents, induced an increase of cellular ROS and killed effectively the tested cells, lactic acidosis (LA), a common tumor environmental factor that plays multifaceted roles in promoting cancer progression, induced a much higher ROS level in the tested cancer cells than PL and PEITC, but spared them; L-buthionine sulfoximine (L-BSO, 20 μM) depleted cellular GSH more effectively and increased higher ROS level than PL or PEITC but permitted progressive growth of the tested cancer cells. No evident dose-response relationship between cellular ROS level and cytotoxicity was observed. If ROS is the effecter, it should obey the fundamental therapeutic principle - the dose-response relationship. This is a major concern. PMID:24848642

  12. Tissue plasminogen activator modulates the cellular and behavioral response to cocaine

    OpenAIRE

    Maiya, Rajani; Zhou, Yan; Norris, Erin H.; Kreek, Mary Jeanne; Strickland, Sidney

    2009-01-01

    Cocaine exposure induces long-lasting molecular and structural adaptations in the brain. In this study, we show that tissue plasminogen activator (tPA), an extracellular protease involved in neuronal plasticity, modulates the biochemical and behavioral response to cocaine. When injected in the acute binge paradigm, cocaine enhanced tPA activity in the amygdala, which required activation of corticotropin-releasing factor type-1 (CRF-R1) receptors. Compared with WT mice, tPA−/− mice injected wi...

  13. Comparative Iron Oxide Nanoparticle Cellular Dosimetry and Response in Mice by the Inhalation and Liquid Cell Culture Exposure Routes

    Energy Technology Data Exchange (ETDEWEB)

    Teeguarden, Justin G.; Mikheev, Vladimir B.; Minard, Kevin R.; Forsythe, William C.; Wang, Wei; Sharma, Gaurav; Karin, Norman J.; Tilton, Susan C.; Waters, Katrina M.; Asgharian, Bahman; Price, Owen; Pounds, Joel G.; Thrall, Brian D.

    2014-01-01

    testing the rapidly growing number of nanomaterials requires large scale use of in vitro systems under the presumption that these systems are sufficiently predictive or descriptive of responses in in vivo systems for effective use in hazard ranking. We hypothesized that improved relationships between in vitro and in vivo models of experimental toxicology for nanomaterials would result from placing response data in vitro and in vivo on the same dose scale, the amount of material associated with cells (target cell dose). Methods: Balb/c mice were exposed nose-only to an aerosol of 12.8 nm (68.6 nm CMD, 19.9 mg/m3, 4 hours) super paramagnetic iron oxide particles, target cell doses were calculated and biomarkers of response anchored with histological evidence were identified by global transcriptomics. Representative murine epithelial and macrophage cell types were exposed in vitro to the same material in liquid suspension for four hours and levels nanoparticle regulated cytokine transcripts identified in vivo were quantified as a function of measured nanoparticle cellular dose. Results. Target tissue doses of 0.009-0.4 μg SPIO/cm2 lung led to an inflammatory response in the alveolar region characterized by interstitial inflammation and macrophage infiltration. In vitro, higher target tissue doses of ~1.2-4 μg SPIO/ cm2 of cells were required to induce transcriptional regulation of markers of inflammation, CXCL2 CCL3, in C10 lung epithelial cells. Estimated in vivo macrophage SPIO nanoparticle doses ranged from 1-100 pg/cell, and induction of inflammatory markers was observed in vitro in macrophages at doses of 8-35 pg/cell. Conclusions: Application of target tissue dosimetry revealed good correspondence between target cell doses triggering inflammatory processes in vitro and in vivo in the alveolar macrophage population, but not in the epithelial cells of the alveolar region. These findings demonstrate the potential for target tissue dosimetry to enable the more

  14. A priming dose of protons alters the early cardiac cellular and molecular response to 56Fe irradiation

    Science.gov (United States)

    Ramadan, Samy S.; Sridharan, Vijayalakshmi; Koturbash, Igor; Miousse, Isabelle R.; Hauer-Jensen, Martin; Nelson, Gregory A.; Boerma, Marjan

    2016-02-01

    Purpose: Recent evidence suggests that the heart may be injured by ionizing radiation at lower doses than was previously thought. This raises concerns about the cardiovascular risks from exposure to radiation during space travel. Since space travel is associated with exposure to both protons from solar particle events and heavy ions from galactic cosmic rays, we here examined the effects of a "priming" dose of protons on the cardiac cellular and molecular response to a "challenge" dose of 56Fe in a mouse model. Methods: Male C57BL/6 mice at 10 weeks of age were exposed to sham-irradiation, 0.1 Gy of protons (150 MeV), 0.5 Gy of 56Fe (600 MeV/n), or 0.1 Gy of protons 24 hours prior to 0.5 Gy of 56Fe. Hearts were obtained at 7 days post-irradiation and western-blots were used to determine protein markers of cardiac remodeling, inflammatory infiltration, and cell death. Results: Exposure to 56Fe caused an increase in expression of α-smooth muscle cell actin, collagen type III, the inflammatory cell markers mast cell tryptase, CD2 and CD68, the endothelial glycoprotein thrombomodulin, and cleaved caspase 3. Of all proteins investigated, protons at a dose of 0.1 Gy induced a small increase only in cleaved caspase 3 levels. On the other hand, exposure to protons 24 hours before 56Fe prevented all of the responses to 56Fe. Conclusions: This study shows that a low dose of protons may prime the heart to respond differently to a subsequent challenge dose of heavy ions. Further investigation is required to identify responses at additional time points, consequences for cardiac function, threshold dose levels, and mechanisms by which a proton priming dose may alter the response to heavy ions.

  15. Another Facet to the Anticancer Response to Lamellarin D: Induction of Cellular Senescence through Inhibition of Topoisomerase I and Intracellular Ros Production

    Directory of Open Access Journals (Sweden)

    Caroline Ballot

    2014-01-01

    Full Text Available Lamellarin D (LamD is a marine alkaloid with broad spectrum antitumor activities. Multiple intracellular targets of LamD, which affect cancer cell growth and induce apoptosis, have been identified. These include nuclear topoisomerase I, relevant kinases (such as cyclin-dependent kinase 2 and the mitochondrial electron transport chain. While we have previously demonstrated that LamD at micromolar range deploys strong cytotoxicity by inducing mitochondrial apoptosis, mechanisms of its cytostatic effect have not yet been characterized. Here, we demonstrated that induction of cellular senescence (depicted by cell cycle arrest in G2 associated with β-galactosidase activity is a common response to subtoxic concentrations of LamD. Cellular senescence is observed in a large panel of cancer cells following in vitro or in vivo exposure to LamD. The onset of cellular senescence is dependent on the presence of intact topoisomerase I since topoisomerase I-mutated cells are resistant to senescence induced by LamD. LamD-induced senescence occurs without important loss of telomere integrity. Instead, incubation with LamD results in the production of intracellular reactive oxygen species (ROS, which are critical for senescence as demonstrated by the inhibitory effect of antioxidants. In addition, cancer cells lacking mitochondrial DNA also exhibit cellular senescence upon LamD exposure indicating that LamD can trigger senescence, unlike apoptosis, in the absence of functional mitochondria. Overall, our results identify senescence-associated growth arrest as a powerful effect of LamD and add compelling evidence for the pharmacological interest of lamellarins as potential anticancer agents.

  16. Curcumin-induced inhibition of cellular reactive oxygen species generation: Novel therapeutic implications

    Indian Academy of Sciences (India)

    M Balasubramanyam; A Adaikala Koteswari; R Sampath Kumar; S Finny Monickaraj; J Uma Maheswari; V Mohan

    2003-12-01

    There is evidence for increased levels of circulating reactive oxygen species (ROS) in diabetics, as indirectly inferred by the findings of increased lipid peroxidation and decreased antioxidant status. Direct measurements of intracellular generation of ROS using fluorescent dyes also demonstrate an association of oxidative stress with diabetes. Although phenolic compounds attenuate oxidative stress-related tissue damage, there are concerns over toxicity of synthetic phenolic antioxidants and this has considerably stimulated interest in investigating the role of natural phenolics in medicinal applications. Curcumin (the primary active principle in turmeric, Curcuma longa Linn.) has been claimed to represent a potential antioxidant and antiinflammatory agent with phytonutrient and bioprotective properties. However there are lack of molecular studies to demonstrate its cellular action and potential molecular targets. In this study the antioxidant effect of curcumin as a function of changes in cellular ROS generation was tested. Our results clearly demonstrate that curcumin abolished both phorbol-12 myristate-13 acetate (PMA) and thapsigargin-induced ROS generation in cells from control and diabetic subjects. The pattern of these ROS inhibitory effects as a function of dose-dependency suggests that curcumin mechanistically interferes with protein kinase C (PKC) and calcium regulation. Simultaneous measurements of ROS and Ca2+ influx suggest that a rise in cytosolic Ca2+ may be a trigger for increased ROS generation. We suggest that the antioxidant and antiangeogenic actions of curcumin, as a mechanism of inhibition of Ca2+ entry and PKC activity, should be further exploited to develop suitable and novel drugs for the treatment of diabetic retinopathy and other diabetic complications.

  17. Novel Adenovirus type 5 vaccine platform induces cellular immunity against HIV-1 Gag, Pol, Nef despite the presence of Ad5 immunity.

    Science.gov (United States)

    Gabitzsch, Elizabeth S; Xu, Younong; Yoshida, Lois H; Balint, Joseph; Amalfitano, Andrea; Jones, Frank R

    2009-10-30

    Recombinant Adenovirus serotype 5 (Ad5) vectors have been used as vaccine platforms in numerous animal and human clinical studies. The immune response induced by Ad5 vaccines can be mitigated due to pre-existing Ad5 immunity. We previously reported the use of a novel Ad5 platform to induce cellular immune responses (CMI) against HIV-1 Gag in Ad5 hyper immune mice. Here, the effectiveness of the Ad5 [E1-, E2b-] vaccine platform was evaluated using a triad mixture of HIV-1 Gag, Pol, and Nef as antigenic transgenes. Broad CMI was induced following vaccination with the HIV-1 expressing vectors in Ad5 naïve and Ad5 immunized mice. A mixture of the three vaccines induced CMI against each transgene product even in the presence of hyper Ad5 immunity. These studies revealed that CMI responses to immunization with Ad5 [E1-, E2b-]-gag, Ad5 [E1-, E2b-]-pol or Ad5 [E1-, E2b-]-nef vectors were transgene specific and did not induce CMI responses against irrelevant antigens such as carcinoembryonic antigen (CEA), herpes simplex virus glycoprotein B (HSV), cytomegalovirus (CMV) or influenza virus antigens. We are evaluating this recombinant triad viral vector as an HIV-1 vaccine in a non-human primate model and the data indicate that the vaccine is worthy of clinical evaluation. PMID:19559110

  18. Midkine secretion protects Hep3B cells from cadmium induced cellular damage

    Institute of Scientific and Technical Information of China (English)

    Nuray Yazihan; Haluk Ataoglu; Ethem Akcil; Burcu Yener; Bulent Salman; Cengiz Aydin

    2008-01-01

    AIM:To evaluate role of midkine secretion during Cadmium (Cd) exposure in the human hepatocyte cell line Hep3B cells.METHODS: Different dosages of Cd (0.5-1-5-10 μg/mL) were applied to Hep3B cells and their effects to apoptosis, lactate dehydrogenase (LDH) leakage and midkine secretion were evaluated as time dependent manner. Same experiments were repeated with exogenously applied midkine (250-5000 pg/mL) and/or 5μg/mL Cd.RESULTS: Cd exposure induced prominent apoptosis and LDH leakage beginning from lower dosages at the 48th h. Cd induced midkine secretion with higher dosages (P < 0.001), (control, Cd 0.5-1-5-10μg/mL respectively: 1123±73, 1157±63, 1242±90, 1886± 175, 1712±166 pg/mL). Exogenous 500-5000 pg/mL midkine application during 5 μg/mL Cd toxicity prevented caspase-3 activation (control, Cd toxicity, 250, 500, 1000, 2500, 5000 pg/mL midkine+ Cd toxicity, respectively:374±64, 1786±156, 1545±179, 1203±113, 974±116, 646±56, 556±63 cfu) LDH leakage and cell death in Hep3B cells (P < 0.001).CONCLUSION: Our results showed that midkine secretion from Hep3B cells during Cd exposure protects liver cells from Cd induced cellular damage. Midkine has anti-apoptotic and cytoprotective role during Cd toxicity. Further studies are needed to explain the mechanism of midkine secretion and cytoprotective role of midkine during Cd exposure. Midkine may be a promising theurapatic agent in different toxic hepatic diseases.

  19. 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.

  20. Innate cellular sources of interleukin-17A regulate macrophage accumulation in cigarette- smoke-induced lung inflammation in mice.

    Science.gov (United States)

    Bozinovski, Steven; Seow, Huei Jiunn; Chan, Sheau Pyng Jamie; Anthony, Desiree; McQualter, Jonathan; Hansen, Michelle; Jenkins, Brendan J; Anderson, Gary P; Vlahos, Ross

    2015-11-01

    Cigarette smoke (CS) is the major cause of chronic obstructive pulmonary disease (COPD). Interleukin-17A (IL-17A) is a pivotal cytokine that regulates lung immunity and inflammation. The aim of the present study was to investigate how IL-17A regulates CS-induced lung inflammation in vivo. IL-17A knockout (KO) mice and neutralization of IL-17A in wild-type (WT) mice reduced macrophage and neutrophil recruitment and chemokine (C-C motif) ligand 2 (CCL2), CCL3 and matrix metalloproteinase (MMP)-12 mRNA expression in response to acute CS exposure. IL-17A expression was increased in non-obese diabetic (NOD) severe combined immunodeficiency SCID) mice with non-functional B- and T-cells over a 4-week CS exposure period, where macrophages accumulated to the same extent as in WT mice. Gene expression analysis by QPCR (quantitative real-time PCR) of isolated immune cell subsets detected increased levels of IL-17A transcript in macrophages, neutrophils and NK/NKT cells in the lungs of CS-exposed mice. In order to further explore the relative contribution of innate immune cellular sources, intracellular IL-17A staining was performed. In the present study, we demonstrate that CS exposure primes natural killer (NK), natural killer T (NKT) and γδ T-cells to produce more IL-17A protein and CS alone increased the frequency of IL17+ γδ T-cells in the lung, whereas IL-17A protein was not detected in macrophages and neutrophils. Our data suggest that activation of innate cellular sources of IL-17A is an essential mediator of macrophage accumulation in CS-exposed lungs. Targeting non-conventional T-cell sources of IL-17A may offer an alternative strategy to reduce pathogenic macrophages in COPD. PMID:26201093

  1. 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

  2. A Drosophila immune response against Ras-induced overgrowth

    Directory of Open Access Journals (Sweden)

    Thomas Hauling

    2014-03-01

    Full Text Available Our goal is to characterize the innate immune response against the early stage of tumor development. For this, animal models where genetic changes in specific cells and tissues can be performed in a controlled way have become increasingly important, including the fruitfly Drosophila melanogaster. Many tumor mutants in Drosophila affect the germline and, as a consequence, also the immune system itself, making it difficult to ascribe their phenotype to a specific tissue. Only during the past decade, mutations have been induced systematically in somatic cells to study the control of tumorous growth by neighboring cells and by immune cells. Here we show that upon ectopic expression of a dominant-active form of the Ras oncogene (RasV12, both imaginal discs and salivary glands are affected. Particularly, the glands increase in size, express metalloproteinases and display apoptotic markers. This leads to a strong cellular response, which has many hallmarks of the granuloma-like encapsulation reaction, usually mounted by the insect against larger foreign objects. RNA sequencing of the fat body reveals a characteristic humoral immune response. In addition we also identify genes that are specifically induced upon expression of RasV12. As a proof-of-principle, we show that one of the induced genes (santa-maria, which encodes a scavenger receptor, modulates damage to the salivary glands. The list of genes we have identified provides a rich source for further functional characterization. Our hope is that this will lead to a better understanding of the earliest stage of innate immune responses against tumors with implications for mammalian immunity.

  3. Frequent biphasic cellular responses of permanent fish cell cultures to deoxynivalenol (DON)

    International Nuclear Information System (INIS)

    Contamination of animal feed with mycotoxins is a major problem for fish feed mainly due to usage of contaminated ingredients for production and inappropriate storage of feed. The use of cereals for fish food production further increases the risk of a potential contamination. Potential contaminants include the mycotoxin deoxynivalenol (DON) which is synthesized by globally distributed fungi of the genus Fusarium. The toxicity of DON is well recognized in mammals. In this study, we confirm cytotoxic effects of DON in established permanent fish cell lines. We demonstrate that DON is capable of influencing the metabolic activity and cell viability in fish cells as determined by different assays to indicate possible cellular targets of this toxin. Evaluation of cell viability by measurement of membrane integrity, mitochondrial activity and lysosomal function after 24 h of exposure of fish cell lines to DON at a concentration range of 0-3000 ng ml-1 shows a biphasic effect on cells although differences in sensitivity occur. The cell lines derived from rainbow trout are particularly sensitive to DON. The focus of this study lies, furthermore, on the effects of DON at different concentrations on production of reactive oxygen species (ROS) in the different fish cell lines. The results show that DON mainly reduces ROS production in all cell lines that were used. Thus, our comparative investigations reveal that the fish cell lines show distinct species-related endpoint sensitivities that also depend on the type of tissue from which the cells were derived and the severity of exposure. - Highlights: → DON uptake by cells is not extensive. → All fish cell lines are sensitive to DON. → DON is most cytotoxic to rainbow trout cells. → Biphasic cellular responses were frequently observed. → Our results are similar to studies on mammalian cell lines.

  4. 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

  5. Cerium dioxide nanoparticles can interfere with the associated cellular mechanistic response to diesel exhaust exposure.

    Science.gov (United States)

    Steiner, Sandro; Mueller, Loretta; Popovicheva, Olga B; Raemy, David O; Czerwinski, Jan; Comte, Pierre; Mayer, Andreas; Gehr, Peter; Rothen-Rutishauser, Barbara; Clift, Martin J D

    2012-10-17

    The aim of this study was to compare the biological response of a sophisticated in vitro 3D co-culture model of the epithelial airway barrier to a co-exposure of CeO(2) NPs and diesel exhaust using a realistic air-liquid exposure system. Independent of the individual effects of either diesel exhaust or CeO(2) NPs investigation observed that a combined exposure of CeO(2) NPs and diesel exhaust did not cause a significant cytotoxic effect or alter cellular morphology after exposure to diesel exhaust for 2h at 20μg/ml (low dose) or for 6h at 60μg/ml (high dose), and a subsequent 6h exposure to an aerosolized solution of CeO(2) NPs at the same doses. A significant loss in the reduced intracellular glutathione level was recorded, although a significant increase in the oxidative marker HMOX-1 was found after exposure to a low and high dose respectively. Both the gene expression and protein release of tumour necrosis factor-α were significantly elevated after a high dose exposure only. In conclusion, CeO(2) NPs, in combination with diesel exhaust, can significantly interfere with the cell machinery, indicating a specific, potentially adverse role of CeO(2) NPs in regards to the biological response of diesel exhaust exposure. PMID:22960666

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

    International Nuclear Information System (INIS)

    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.

  7. 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.

  8. 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.

  9. Epitope specificity of human immunodeficiency virus-1 antibody dependent cellular cytotoxicity [ADCC] responses.

    Science.gov (United States)

    Pollara, Justin; Bonsignori, Mattia; Moody, M Anthony; Pazgier, Marzena; Haynes, Barton F; Ferrari, Guido

    2013-07-01

    Antibody dependent cellular cytotoxicity [ADCC] has been suggested to play an important role in control of Human Immunodeficiency Virus-1 [HIV-1] viral load and protection from infection. ADCC antibody responses have been mapped to multiple linear and conformational epitopes within the HIV-1 envelope glycoproteins gp120 and gp41. Many epitopes targeted by antibodies that mediate ADCC overlap with those recognized by antibodies capable of virus neutralization. In addition, recent studies conducted with human monoclonal antibodies derived from HIV-1 infected individuals and HIV-1 vaccine-candidate vaccinees have identified a number of antibodies that lack the ability to capture primary HIV-1 isolates or mediate neutralizing activity, but are able to bind to the surface of infected CD4+ T cells and mediate ADCC. Of note, the conformational changes in the gp120 that may not exclusively relate to binding of the CD4 molecule are important in exposing epitopes recognized by ADCC responses. Here we discuss the HIV-1 envelope epitopes targeted by ADCC antibodies in the context of the potential protective capacities of ADCC. PMID:24191939

  10. Cellular response to substrate rigidity is governed by either stress or strain.

    Science.gov (United States)

    Yip, Ai Kia; Iwasaki, Katsuhiko; Ursekar, Chaitanya; Machiyama, Hiroaki; Saxena, Mayur; Chen, Huiling; Harada, Ichiro; Chiam, Keng-Hwee; Sawada, Yasuhiro

    2013-01-01

    Cells sense the rigidity of their substrate; however, little is known about the physical variables that determine their response to this rigidity. Here, we report traction stress measurements carried out using fibroblasts on polyacrylamide gels with Young's moduli ranging from 6 to 110 kPa. We prepared the substrates by employing a modified method that involves N-acryloyl-6-aminocaproic acid (ACA). ACA allows for covalent binding between proteins and elastomers and thus introduces a more stable immobilization of collagen onto the substrate when compared to the conventional method of using sulfo-succinimidyl-6-(4-azido-2-nitrophenyl-amino) hexanoate (sulfo-SANPAH). Cells remove extracellular matrix proteins off the surface of gels coated using sulfo-SANPAH, which corresponds to lower values of traction stress and substrate deformation compared to gels coated using ACA. On soft ACA gels (Young's modulus 20 kPa), traction stress plateaus at a limiting value and the substrate deformation decreases with increasing substrate rigidity. Sustained substrate strain on soft substrates and sustained traction stress on stiff substrates suggest these may be factors governing cellular responses to substrate rigidity. PMID:23332055

  11. Sleep Loss as a Factor to Induce Cellular and Molecular Inflammatory Variations

    Directory of Open Access Journals (Sweden)

    Gabriela Hurtado-Alvarado

    2013-01-01

    Full Text Available A reduction in the amount of time spent sleeping occurs chronically in modern society. Clinical and experimental studies in humans and animal models have shown that immune function is impaired when sleep loss is experienced. Sleep loss exerts a strong regulatory influence on peripheral levels of inflammatory mediators of the immune response. An increasing number of research projects support the existence of reciprocal regulation between sleep and low-intensity inflammatory response. Recent studies show that sleep deficient humans and rodents exhibit a proinflammatory component; therefore, sleep loss is considered as a risk factor for developing cardiovascular, metabolic, and neurodegenerative diseases (e.g., diabetes, Alzheimer's disease, and multiple sclerosis. Circulating levels of proinflammatory mediators depend on the intensity and duration of the method employed to induce sleep loss. Recognizing the fact that the concentration of proinflammatory mediators is different between acute and chronic sleep-loss may expand the understanding of the relationship between sleep and the immune response. The aim of this review is to integrate data from recent published reports (2002–2013 on the effects of sleep loss on the immune response. This review may allow readers to have an integrated view of the mechanisms involved in central and peripheral deficits induced by sleep loss.

  12. Pb-induced cellular defense system in the root meristematic cells of Allium sativum L

    Directory of Open Access Journals (Sweden)

    Liu Donghua

    2010-03-01

    Full Text Available Abstract Background Electron microscopy (EM techniques enable identification of the main accumulations of lead (Pb in cells and cellular organelles and observations of changes in cell ultrastructure. Although there is extensive literature relating to studies on the influence of heavy metals on plants, Pb tolerance strategies of plants have not yet been fully explained. Allium sativum L. is a potential plant for absorption and accumulation of heavy metals. In previous investigations the effects of different concentrations (10-5 to 10-3 M of Pb were investigated in A. sativum, indicating a significant inhibitory effect on shoot and root growth at 10-3 to 10-4 M Pb. In the present study, we used EM and cytochemistry to investigate ultrastructural alterations, identify the synthesis and distribution of cysteine-rich proteins induced by Pb and explain the possible mechanisms of the Pb-induced cellular defense system in A. sativum. Results After 1 h of Pb treatment, dictyosomes were accompanied by numerous vesicles within cytoplasm. The endoplasm reticulum (ER with swollen cisternae was arranged along the cell wall after 2 h. Some flattened cisternae were broken up into small closed vesicles and the nuclear envelope was generally more dilated after 4 h. During 24-36 h, phenomena appeared such as high vacuolization of cytoplasm and electron-dense granules in cell walls, vacuoles, cytoplasm and mitochondrial membranes. Other changes included mitochondrial swelling and loss of cristae, and vacuolization of ER and dictyosomes during 48-72 h. In the Pb-treatment groups, silver grains were observed in cell walls and in cytoplasm, suggesting the Gomori-Swift reaction can indirectly evaluate the Pb effects on plant cells. Conclusions Cell walls can immobilize some Pb ions. Cysteine-rich proteins in cell walls were confirmed by the Gomori-Swift reaction. The morphological alterations in plasma membrane, dictyosomes and ER reflect the features of detoxification

  13. Inhibition of cellular proliferation by the Wilms tumor suppressor WT1 requires association with the inducible chaperone Hsp70

    OpenAIRE

    Maheswaran, Shyamala; Englert, Christoph; Zheng, Gang; Lee, Sean Bong; Wong, Jenise; Harkin, D Paul; Bean, James; Ezzell, Robert; Garvin, A. Julian; McCluskey, Robert T.; DeCaprio, James A.; Haber, Daniel A.

    1998-01-01

    The Wilms tumor suppressor WT1 encodes a zinc finger transcription factor that is expressed in glomerular podocytes during a narrow window in kidney development. By immunoprecipitation and protein microsequencing analysis, we have identified a major cellular protein associated with endogenous WT1 to be the inducible chaperone Hsp70. WT1 and Hsp70 are physically associated in embryonic rat kidney cells, in primary Wilms tumor specimens and in cultured cells with inducible expression of WT1. Co...

  14. The reconstitution of the thymus in immunosuppressed individuals restores CD4-specific cellular and humoral immune responses.

    Science.gov (United States)

    Plana, Montserrat; Garcia, Felipe; Darwich, Laila; Romeu, Joan; López, Anna; Cabrera, Cecilia; Massanella, Marta; Canto, Esther; Ruiz-Hernandez, Raul; Blanco, Julià; Sánchez, Marcelo; Gatell, Josep M; Clotet, Bonaventura; Ruiz, Lidia; Bofill, Margarita

    2011-07-01

    Infection with HIV-1 frequently results in the loss of specific cellular immune responses and an associated lack of antibodies. Recombinant growth hormone (rGH) administration reconstitutes thymic tissue and boosts the levels of peripheral T cells, so rGH therapy may be an effective adjuvant through promoting the recovery of lost cellular and T-cell-dependent humoral immune responses in immunosuppressed individuals. To test this concept, we administered rGH to a clinically defined group of HIV-1-infected subjects with defective cellular and serological immune responses to at least one of three commonly employed vaccines (hepatitis A, hepatitis B or tetanus toxoid). Of the original 278 HIV-1-infected patients entering the trial, only 20 conformed to these immunological criteria and were randomized into three groups: Group A (n = 8) receiving rGH and challenged with the same vaccine to which they were unresponsive and Groups B (n = 5) and C (n = 7) who received either rGH or vaccination alone, respectively. Of the eight subjects in Group A, five recovered CD4 cellular responses to vaccine antigen and four of these produced the corresponding antibodies. In the controls, three of the five in group B recovered cellular responses with two producing antibodies, whereas three of the seven in Group C recovered CD4 responses, with only two producing antibodies. Significantly, whereas seven of ten patients receiving rGH treatment in Group A (six patients) and B (one patient) recovered T-cell responses to HIVp24, only two of six in Group C responded similarly. In conclusion, reconstitution of the thymus in immunosuppressed adults through rGH hormone treatment restored both specific antibody and CD4 T-cell responses. PMID:21501161

  15. Sand fly salivary proteins induce strong cellular immunity in a natural reservoir of visceral leishmaniasis with adverse consequences for Leishmania.

    OpenAIRE

    Nicolas Collin; Regis Gomes; Clarissa Teixeira; Lily Cheng; Andre Laughinghouse; Ward, Jerrold M.; Dia-Eldin Elnaiem; Laurent Fischer; Valenzuela, Jesus G.; Shaden Kamhawi

    2009-01-01

    Immunity to a sand fly salivary protein protects against visceral leishmaniasis (VL) in hamsters. This protection was associated with the development of cellular immunity in the form of a delayed-type hypersensitivity response and the presence of IFN-gamma at the site of sand fly bites. To date, there are no data available regarding the cellular immune response to sand fly saliva in dogs, the main reservoirs of VL in Latin America, and its role in protection from this fatal disease. Two of 35...

  16. Curcumin Differs from Tetrahydrocurcumin for Molecular Targets, Signaling Pathways and Cellular Responses

    Directory of Open Access Journals (Sweden)

    Bharat B. Aggarwal

    2014-12-01

    Full Text Available Curcumin (diferuloylmethane, a golden pigment from turmeric, has been linked with antioxidant, anti-inflammatory, anticancer, antiviral, antibacterial, and antidiabetic properties. Most of the these activities have been assigned to methoxy, hydroxyl, α,β-unsaturated carbonyl moiety or to diketone groups present in curcumin. One of the major metabolites of curcumin is tetrahydrocurcumin (THC, which lacks α,β-unsaturated carbonyl moiety and is white in color. Whether THC is superior to curcumin on a molecular level is unclear and thus is the focus of this review. Various studies suggest that curcumin is a more potent antioxidant than THC; curcumin (but not THC can bind and inhibit numerous targets including DNA (cytosine-5-methyltransferase-1, heme oxygenase-1, Nrf2, β-catenin, cyclooxygenase-2, NF-kappaB, inducible nitric oxide synthase, nitric oxide, amyloid plaques, reactive oxygen species, vascular endothelial growth factor, cyclin D1, glutathione, P300/CBP, 5-lipoxygenase, cytosolic phospholipase A2, prostaglandin E2, inhibitor of NF-kappaB kinase-1, -2, P38MAPK, p-Tau, tumor necrosis factor-α, forkhead box O3a, CRAC; curcumin can inhibit tumor cell growth and suppress cellular entry of viruses such as influenza A virus and hepatitis C virus much more effectively than THC; curcumin affects membrane mobility; and curcumin is also more effective than THC in suppressing phorbol-ester-induced tumor promotion. Other studies, however, suggest that THC is superior to curcumin for induction of GSH peroxidase, glutathione-S-transferase, NADPH: quinone reductase, and quenching of free radicals. Most studies have indicated that THC exhibits higher antioxidant activity, but curcumin exhibits both pro-oxidant and antioxidant properties.

  17. CELLULAR AND POPULATION PLASTICITY OF HELPER CD4 T CELL RESPONSES

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    Gesham eMagombedze

    2013-08-01

    Full Text Available Vertebrates are constantly exposed to pathogens, and the adaptive immunity has most likely evolved to control and clear such infectious agents. CD4 T cells are the major players in the adaptive immune response to pathogens. Following recognition of pathogen-derived antigens naïve CD4 T cells differentiate into effectors which then control pathogen replication either directly by killing pathogen-infected cells or by assisting with generation of cytotoxic T lymphocytes or pathogen-specific antibodies. Pathogen-specific effector CD4 T cells are highly heterogeneous in terms of cytokines they produce. Three major subtypes of effector CD4 T cells have been identified: T-helper 1 (Th1 cells producing IFN-g and TNF-α, Th2 cells producing IL-4 and IL-10, and Th17 cells producing IL-17. How this heterogeneity is maintained and what regulates changes in effector T cell composition during chronic infections remains poorly understood. In this review we discuss recent advances in our understanding of CD4 T cell differentiation in response to microbial infections. We propose that a change in the phenotype of pathogen-specific effector CD4 T cells during chronic infections, for example, from Th1 to Th2 response as observed in Mycobacteriumavium ssp. paratuberculosis (MAP infection of ruminants, can be achieved by conversion of T cells from one effector subset to another (cellular plasticity or due to differences in kinetics (differentiation, proliferation, death of different effector T cell subsets (population plasticity. We also shortly review mathematical models aimed at describing CD4 T cell differentiation and outline areas for future experimental and theoretical research.

  18. HIV-1 transgenic rats display alterations in immunophenotype and cellular responses associated with aging.

    Directory of Open Access Journals (Sweden)

    Susan J Abbondanzo

    Full Text Available Advances in anti-retroviral therapy over the last two decades have allowed life expectancy in patients infected with the human immunodeficiency virus to approach that of the general population. The process of aging in mammalian species, including rats, results in immune response changes, alterations in immunological phenotypes, and ultimately increased susceptibility to many infectious diseases. In order to investigate the immunological pathologies associated with chronic HIV-1 disease, particularly in aging individuals, the HIV-1 transgenic (HIV-1Tg rat model was utilized. HIV-1Tg rats were challenged with lipopolysaccharide (LPS to determine immunological alterations during the aging process. LPS is known to cause an imbalance in cytokine and chemokine release, and provides a method to identify changes in immune responses to bacterial infection in an HIV animal model. An immune profile and accompanying cellular consequences as well as changes in inflammatory cytokine and chemokine release related to age and genotype were assessed in HIV-1Tg rats. The percentage of T cells decreased with age, particularly T cytotoxic cells, whereas T helper cells increased with age. Neutrophils and monocytes increased in HIV-1Tg rats during maturation compared to age-matched F344 control rats. Aging HIV-1Tg rats displayed a significant increase in the pro-inflammatory cytokines, IL-6 and TNF-α, along with an increase in the chemokine, KC/GRO, in comparison to age-matched controls. Our data indicate that immunophenotype and immune responses can change during aging in HIV-positive individuals. This information could be important in determining the most beneficial age-dependent therapeutic treatment for HIV patients.

  19. 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

  20. 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

  1. Propofol ameliorates doxorubicin-induced oxidative stress and cellular apoptosis in rat cardiomyocytes

    International Nuclear Information System (INIS)

    Background: Propofol is an anesthetic with pluripotent cytoprotective properties against various extrinsic insults. This study was designed to examine whether this agent could also ameliorate the infamous toxicity of doxorubicin, a widely-used chemotherapeutic agent against a variety of cancer diseases, on myocardial cells. Methods: Cultured neonatal rat cardiomyocytes were administrated with vehicle, doxorubicin (1 μM), propofol (1 μM), or propofol plus doxorubicin (given 1 h post propofol). After 24 h, cells were harvested and specific analyses regarding oxidative/nitrative stress and cellular apoptosis were conducted. Results: Trypan blue exclusion and MTT assays disclosed that viability of cardiomyocytes was significantly reduced by doxorubicin. Contents of reactive oxygen and nitrogen species were increased and antioxidant enzymes SOD1, SOD2, and GPx were decreased in these doxorubicin-treated cells. Mitochondrial dehydrogenase activity and membrane potential were also depressed, along with activation of key effectors downstream of mitochondrion-dependent apoptotic signaling. Besides, abundance of p53 was elevated and cleavage of PKC-δ was induced in these myocardial cells. In contrast, all of the above oxidative, nitrative and pro-apoptotic events could be suppressed by propofol pretreatment. Conclusions: Propofol could extensively counteract oxidative/nitrative and multiple apoptotic effects of doxorubicin in the heart; hence, this anesthetic may serve as an adjuvant agent to assuage the untoward cardiac effects of doxorubicin in clinical application. -- Highlights: ► We evaluate how propofol prevents doxorubicin-induced toxicity in cardiomyocytes. ► Propofol reduces doxorubicin-imposed nitrative and oxidative stress. ► Propofol suppresses mitochondrion-, p53- and PKC-related apoptotic signaling. ► Propofol ameliorates apoptosis and preserves viability of doxorubicin-treated cells. ► Thus, propofol could effectively antagonize doxorubicin

  2. Propofol ameliorates doxorubicin-induced oxidative stress and cellular apoptosis in rat cardiomyocytes

    Energy Technology Data Exchange (ETDEWEB)

    Lai, H.C. [Cardiovascular Center and Department of Anesthesiology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Department of Medicine and Cardiovascular Research Center, National Yang-Ming University School of Medicine, Taipei, Taiwan (China); Yeh, Y.C. [Graduate Institute of Natural Healing Sciences, Nanhua University, Chiayi, Taiwan (China); Wang, L.C. [Cardiovascular Center and Department of Anesthesiology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Ting, C.T.; Lee, W.L. [Cardiovascular Center and Department of Anesthesiology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Department of Medicine and Cardiovascular Research Center, National Yang-Ming University School of Medicine, Taipei, Taiwan (China); Lee, H.W. [Cardiovascular Center and Department of Anesthesiology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Wang, K.Y. [Cardiovascular Center and Department of Anesthesiology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Department of Medicine, Chung-Shan Medical University, Taichung, Taiwan (China); Wu, A. [College of Biological Science, University of California, Davis (United States); Su, C.S. [Cardiovascular Center and Department of Anesthesiology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Department of Medicine and Cardiovascular Research Center, National Yang-Ming University School of Medicine, Taipei, Taiwan (China); Liu, T.J., E-mail: trliu@vghtc.gov.tw [Cardiovascular Center and Department of Anesthesiology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Department of Medicine and Cardiovascular Research Center, National Yang-Ming University School of Medicine, Taipei, Taiwan (China)

    2011-12-15

    Background: Propofol is an anesthetic with pluripotent cytoprotective properties against various extrinsic insults. This study was designed to examine whether this agent could also ameliorate the infamous toxicity of doxorubicin, a widely-used chemotherapeutic agent against a variety of cancer diseases, on myocardial cells. Methods: Cultured neonatal rat cardiomyocytes were administrated with vehicle, doxorubicin (1 {mu}M), propofol (1 {mu}M), or propofol plus doxorubicin (given 1 h post propofol). After 24 h, cells were harvested and specific analyses regarding oxidative/nitrative stress and cellular apoptosis were conducted. Results: Trypan blue exclusion and MTT assays disclosed that viability of cardiomyocytes was significantly reduced by doxorubicin. Contents of reactive oxygen and nitrogen species were increased and antioxidant enzymes SOD1, SOD2, and GPx were decreased in these doxorubicin-treated cells. Mitochondrial dehydrogenase activity and membrane potential were also depressed, along with activation of key effectors downstream of mitochondrion-dependent apoptotic signaling. Besides, abundance of p53 was elevated and cleavage of PKC-{delta} was induced in these myocardial cells. In contrast, all of the above oxidative, nitrative and pro-apoptotic events could be suppressed by propofol pretreatment. Conclusions: Propofol could extensively counteract oxidative/nitrative and multiple apoptotic effects of doxorubicin in the heart; hence, this anesthetic may serve as an adjuvant agent to assuage the untoward cardiac effects of doxorubicin in clinical application. -- Highlights: Black-Right-Pointing-Pointer We evaluate how propofol prevents doxorubicin-induced toxicity in cardiomyocytes. Black-Right-Pointing-Pointer Propofol reduces doxorubicin-imposed nitrative and oxidative stress. Black-Right-Pointing-Pointer Propofol suppresses mitochondrion-, p53- and PKC-related apoptotic signaling. Black-Right-Pointing-Pointer Propofol ameliorates apoptosis and

  3. Stanniocalcin 2 alters PERK signalling and reduces cellular injury during cerulein induced pancreatitis in mice

    Directory of Open Access Journals (Sweden)

    DiMattia Gabriel E

    2011-05-01

    Full Text Available Abstract Background Stanniocalcin 2 (STC2 is a secreted protein activated by (PKR-like Endoplasmic Reticulum Kinase (PERK signalling under conditions of ER stress in vitro. Over-expression of STC2 in mice leads to a growth-restricted phenotype; however, the physiological function for STC2 has remained elusive. Given the relationship of STC2 to PERK signalling, the objective of this study was to examine the role of STC2 in PERK signalling in vivo. Results Since PERK signalling has both physiological and pathological roles in the pancreas, STC2 expression was assessed in mouse pancreata before and after induction of injury using a cerulein-induced pancreatitis (CIP model. Increased Stc2 expression was identified within four hours of initiating pancreatic injury and correlated to increased activation of PERK signalling. To determine the effect of STC2 over-expression on PERK, mice systemically expressing human STC2 (STC2Tg were examined. STC2Tg pancreatic tissue exhibited normal pancreatic morphology, but altered activation of PERK signalling, including increases in Activating Transcription Factor (ATF 4 accumulation and autophagy. Upon induction of pancreatic injury, STC2Tg mice exhibited limited increases in circulating amylase levels and increased maintenance of cellular junctions. Conclusions This study links STC2 to the pathological activation of PERK in vivo, and suggests involvement of STC2 in responding to pancreatic acinar cell injury.

  4. Cocaine and MDMA Induce Cellular and Molecular Changes in Adult Neurogenic Systems: Functional Implications

    Directory of Open Access Journals (Sweden)

    Vivian Capilla-Gonzalez

    2011-06-01

    Full Text Available The capacity of the brain to generate new adult neurons is a recent discovery that challenges the old theory of an immutable adult brain. A new and fascinating field of research now focuses on this regenerative process. The two brain systems that constantly produce new adult neurons, known as the adult neurogenic systems, are the dentate gyrus (DG of the hippocampus and the lateral ventricules/olfactory bulb system. Both systems are involved in memory and learning processes. Different drugs of abuse, such as cocaine and MDMA, have been shown to produce cellular and molecular changes that affect adult neurogenesis. This review summarizes the effects that these drugs have on the adult neurogenic systems. The functional relevance of adult neurogenesis is obscured by the functions of the systems that integrate adult neurons. Therefore, we explore the effects that cocaine and MDMA produce not only on adult neurogenesis, but also on the DG and olfactory bulbs. Finally, we discuss the possible role of new adult neurons in cocaine- and MDMA-induced impairments. We conclude that, although harmful drug effects are produced at multiple physiological and anatomical levels, the specific consequences of reduced hippocampus neurogenesis are unclear and require further exploration.

  5. Neuroprotective effects of protocatechuic aldehyde against neurotoxin-induced cellular and animal models of Parkinson's disease.

    Directory of Open Access Journals (Sweden)

    Xin Zhao

    Full Text Available Protocatechuic aldehyde (PAL has been reported to bind to DJ-1, a key protein involved in Parkinson's disease (PD, and exerts potential neuroprotective effects via DJ-1 in SH-SY5Y cells. In this study, we investigated the neuroprotective pharmacological effects of PAL against neurotoxin-induced cell and animal models of PD. In cellular models of PD, PAL markedly increased cell viability rates, mitochondrial oxidation-reduction activity and mitochondrial membrane potential, and reduced intracellular ROS levels to prevent neurotoxicity in PC12 cells. In animal models of PD, PAL reduced the apomorphine injection, caused turning in 6-OHDA treated rats, and increased the motor coordination and stride decreases in MPTP treated mice. Meanwhile, in an MPTP mouse model, PAL prevented a decrease of the contents of dopamine (DA and its metabolites in the striatum and TH-positive dopaminergic neuron loss in the substantia nigra (SN. In addition, PAL increased the protein expression of DJ-1 and reduced the level of α-synuclein in the SN of MPTP lesioned mice. PAL also increased the spine density in hippocampal CA1 neurons. The current study demonstrates that PAL can efficiently protect dopaminergic neurons against neurotoxin injury in vitro and in vivo, and that the potential mechanisms may be related to its effects in increasing DJ-1, decreasing α-synuclein and its growth-promoting effect on spine density.

  6. Colon Cancer-associated DNA Polymerase β Variant Induces Genomic Instability and Cellular Transformation*

    Science.gov (United States)

    Nemec, Antonia A.; Donigan, Katherine A.; Murphy, Drew L.; Jaeger, Joachim; Sweasy, Joann B.

    2012-01-01

    Rapidly advancing technology has resulted in the generation of the genomic sequences of several human tumors. We have identified several mutations of the DNA polymerase β (pol β) gene in human colorectal cancer. We have demonstrated that the expression of the pol β G231D variant increased chromosomal aberrations and induced cellular transformation. The transformed phenotype persisted in the cells even once the expression of G231D was extinguished, suggesting that it resulted as a consequence of genomic instability. Biochemical analysis revealed that its catalytic rate was 140-fold slower than WT pol β, and this was a result of the decreased binding affinity of nucleotides by G231D. Residue 231 of pol β lies in close proximity to the template strand of the DNA. Molecular modeling demonstrated that the change from a small and nonpolar glycine to a negatively charged aspartate resulted in a repulsion between the template and residue 231 leading to the distortion of the dNTP binding pocket. In addition, expression of G231D was insufficient to rescue pol β-deficient cells treated with chemotherapeutic agents suggesting that these agents may be effectively used to treat tumors harboring this mutation. More importantly, this suggests that the G231D variant has impaired base excision repair. Together, these data indicate that the G231D variant plays a role in driving cancer. PMID:22573322

  7. Inducible heat shock protein 70 (HSP70) Involves in radioadaptive response

    International Nuclear Information System (INIS)

    Radiation induced fibrosarcoma (RIF) cells did not show the adaptive response, i.e. a reduced effect from a higher challenging dose (4 Gy) of a radiation when a priming dose (1 cGy) had been applied 4 or 7 hrs earlier, but its thermoresistant clone (TR) did. Since inducible HSP70 expression was different between two cell lines, the role of inducible HSP70 in adaptive response was examined. When inducible hsp70 was transfected to RIF cells, the adaptive response was acquired. Inducible hsp70 transfected NIH3T3 mouse embryo cells also conferred radioresistance when detected by clonogenic survival, [3H]-thymidine incoporation, and ELISA cell death detection kit, as well as increased tendency of induction adaptive response. Interestingly, basal levels of Ca2+-dependent and Ca2+-independent PKC activities were increased by inducible HSP70, when compared to those of control vector cells. Irradiation of g-ray induced PKC activation within minutes in control vector cells, while it did not by inducible HSP70. Cellular redistribution to particulate fraction of PKCa, d and z by g-rays was not detected either. Furthermore, radioresistance by inducible HSP70 was disappeared by pre-treatment of PKC inhibitors, 1-(5-isoquinolinesulfomyI)-2-methylpepirazine (H7), prolonged treatment of 12-O-tetradecanoylphorbol-13-acetate (TPA), and GF109203X in clonogenic survival assay. Taken together, these data suggest that inducible HSP70-induced radioresistance is associated with its elevated level of PKC activity

  8. Galleria mellonella larvae are capable of sensing the extent of priming agent and mounting proportionatal cellular and humoral immune responses.

    Science.gov (United States)

    Wu, Gongqing; Xu, Li; Yi, Yunhong

    2016-06-01

    Larvae of Galleria mellonella are useful models for studying the innate immunity of invertebrates or for evaluating the virulence of microbial pathogens. In this work, we demonstrated that prior exposure of G. mellonella larvae to high doses (1×10(4), 1×10(5) or 1×10(6) cells/larva) of heat-killed Photorhabdus luminescens TT01 increases the resistance of larvae to a lethal dose (50 cells/larva) of viable P. luminescens TT01 infection administered 48h later. We also found that the changes in immune protection level were highly correlated to the changes in levels of cellular and humoral immune parameters when priming the larvae with different doses of heat-killed P. luminescens TT01. Priming the larvae with high doses of heat-killed P. luminescens TT01 resulted in significant increases in the hemocytes activities of phagocytosis and encapsulation. High doses of heat-killed P. luminescens TT01 also induced an increase in total hemocyte count and a reduction in bacterial density within the larval hemocoel. Quantitative real-time PCR analysis showed that genes coding for cecropin and gallerimycin and galiomycin increased in expression after priming G. mellonella with heat-killed P. luminescens TT01. All the immune parameters changed in a dose-dependent manner. These results indicate that the insect immune system is capable of sensing the extent of priming agent and mounting a proportionate immune response. PMID:27107784

  9. Neutralizing Antibody Response and Antibody-Dependent Cellular Cytotoxicity in HIV-1-Infected Individuals from Guinea-Bissau and Denmark.

    Science.gov (United States)

    Borggren, Marie; Jensen, Sanne Skov; Heyndrickx, Leo; Palm, Angelica A; Gerstoft, Jan; Kronborg, Gitte; Hønge, Bo Langhoff; Jespersen, Sanne; da Silva, Zacarias José; Karlsson, Ingrid; Fomsgaard, Anders

    2016-05-01

    The development of therapeutic and prophylactic HIV vaccines for African countries is urgently needed, but the question of what immunogens to use needs to be answered. One approach is to include HIV envelope immunogens derived from HIV-positive individuals from a geographically concentrated epidemic with more limited viral genetic diversity for a region-based vaccine. To address if there is a basis for a regional selected antibody vaccine, we have screened two regionally separate cohorts from Guinea-Bissau and Denmark for neutralizing antibody activity and antibody-dependent cellular cytotoxicity (ADCC) against local and nonlocal circulating HIV-1 strains. The neutralizing activity did not demonstrate higher potential against local circulating strains according to geography and subtype determination, but the plasma from Danish individuals demonstrated significantly higher inhibitory activity than that from Guinea-Bissau individuals against both local and nonlocal virus strains. Interestingly, an opposite pattern was observed with ADCC activity, where Guinea-Bissau individual plasma demonstrated higher activity than Danish plasma and was specifically against the local circulating subtype. Thus, on basis of samples from these two cohorts, no local-specific neutralizing activity was detected, but a local ADCC response was identified in the Guinea-Bissau samples, suggesting potential use of regional immunogens for an ADCC-inducing vaccine. PMID:26621287

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

    Directory of Open Access Journals (Sweden)

    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.

  11. An Inducible System for Rapid Degradation of Specific Cellular Proteins Using Proteasome Adaptors

    Science.gov (United States)

    Wilmington, Shameika R.; Matouschek, Andreas

    2016-01-01

    A common way to study protein function is to deplete the protein of interest from cells and observe the response. Traditional methods involve disrupting gene expression but these techniques are only effective against newly synthesized proteins and leave previously existing and stable proteins untouched. Here, we introduce a technique that induces the rapid degradation of specific proteins in mammalian cells by shuttling the proteins to the proteasome for degradation in a ubiquitin-independent manner. We present two implementations of the system in human culture cells that can be used individually to control protein concentration. Our study presents a simple, robust, and flexible technology platform for manipulating intracellular protein levels. PMID:27043013

  12. Electrospun PCL/Gelatin composite fibrous scaffolds: mechanical properties and cellular responses.

    Science.gov (United States)

    Yao, Ruijuan; He, Jing; Meng, Guolong; Jiang, Bo; Wu, Fang

    2016-06-01

    Electrospinning of hybrid polymer has gained widespread interest by taking advantages of the biological property of the natural polymer and the mechanical property of the synthetic polymer. However, the effect of the blend ratio on the above two properties has been less reported despite the importance to balance these two properties in various tissue engineering applications. To this aim, we investigated the electrospun PCL/Gelatin composite fibrous scaffolds with different blend ratios of 4:1, 2:1, 1:1, 1:2, 1:4, respectively. The morphology of the electrospun samples was observed by SEM and the result showed that the fiber diameter distribution became more uniform with the increase of the gelatin content. The mechanical testing results indicated that the 2:1 PCL/Gelatin sample had both the highest tensile strength of 3.7 MPa and the highest elongation rate of about 90%. Surprisingly, the 2:1 PCL/Gelatin sample also showed the best mesenchymal stem cell responses in terms of attachment, spreading, and cytoskeleton organization. Such correlation might be partly due to the fact that the enhanced mechanical property, an integral part of the physical microenvironment, likely played an important role in regulating the cellular functions. Overall, our results indicated that the PCL/Gelatin sample with the blend ratio of 2:1 was a superior candidate for scaffolds for tissue engineering applications. PMID:27044505

  13. Signaling pathways involved in PDGF-evoked cellular responses in human RPE cells

    International Nuclear Information System (INIS)

    We examined whether PDGF may directly stimulate the expression of VEGF by retinal pigment epithelial (RPE) cells in vitro, and the involvement of three signal transduction pathways in the regulation of PDGF-evoked cell proliferation, migration, and production of VEGF-A was investigated. PDGF stimulated the gene and protein expression of VEGF-A by RPE cells, and increased cell proliferation and chemotaxis. PDGF activated all signaling pathways investigated, as determined by increased phosphorylation levels of ERK1/2, p38, and Akt proteins. The three signaling pathways were involved in the mediation of PDGF-evoked cell proliferation, while p38 and PI3K mediated cell migration, and PI3K mediated secretion of VEGF-A. In addition to VEGF-A, the cells expressed mRNAs for various members of the VEGF family and for their receptors, including VEGF-B, -C, -D, flt-1, and KDR. The data indicate that PDGF selectively stimulates the expression of VEGF-A in RPE cells. PDGF evokes at least three signal transduction pathways which are differentially involved in various cellular responses

  14. Genomic interrogation of mechanism(s) underlying cellular responses to toxicants

    International Nuclear Information System (INIS)

    Assessment of the impact of xenobiotic exposure on human health and disease progression is complex. Knowledge of mode(s) of action, including mechanism(s) contributing to toxicity and disease progression, is valuable for evaluating compounds. Toxicogenomics, the subdiscipline which merges genomics with toxicology, holds the promise to contributing significantly toward the goal of elucidating mechanism(s) by studying genome-wide effects of xenobiotics. Global gene expression profiling, revolutionized by microarray technology and a crucial aspect of a toxicogenomic study, allows measuring transcriptional modulation of thousands of genes following exposure to a xenobiotic. We use our results from previous studies on compounds representing two different classes of xenobiotics (barbiturate and peroxisome proliferator) to discuss the application of computational approaches for analyzing microarray data to elucidate mechanism(s) underlying cellular responses to toxicants. In particular, our laboratory demonstrated that chemical-specific patterns of gene expression can be revealed using cDNA microarrays. Transcript profiling provides discrimination between classes of toxicants, as well as, genome-wide insight into mechanism(s) of toxicity and disease progression. Ultimately, the expectation is that novel approaches for predicting xenobiotic toxicity in humans will emerge from such information

  15. Computer simulation of a cellular automata model for the immune response in a retrovirus system

    Science.gov (United States)

    Pandey, R. B.

    1989-02-01

    Immune response in a retrovirus system is modeled by a network of three binary cell elements to take into account some of the main functional features of T4 cells, T8 cells, and viruses. Two different intercell interactions are introduced, one of which leads to three fixed points while the other yields bistable fixed points oscillating between a healthy state and a sick state in a mean field treatment. Evolution of these cells is studied for quenched and annealed random interactions on a simple cubic lattice with a nearest neighbor interaction using inhomogenous cellular automata. Populations of T4 cells and viral cells oscillate together with damping (with constant amplitude) for annealed (quenched) interaction on increasing the value of mixing probability B from zero to a characteristic value B ca ( B cq). For higher B, the average number of T4 cells increases while that of the viral infected cells decreases monotonically on increasing B, suggesting a phase transition at B ca ( B cq).

  16. 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.

  17. Cellular and molecular responses to increased skeletal muscle loading after irradiation

    Science.gov (United States)

    Adams, Gregory R.; Caiozzo, Vincent J.; Haddad, Fadia; Baldwin, Kenneth M.

    2002-01-01

    Irradiation of rat skeletal muscles before increased loading has been shown to prevent compensatory hypertrophy for periods of up to 4 wk, possibly by preventing satellite cells from proliferating and providing new myonuclei. Recent work suggested that stem cell populations exist that might allow irradiated muscles to eventually hypertrophy over time. We report that irradiation essentially prevented hypertrophy in rat muscles subjected to 3 mo of functional overload (OL-Ir). The time course and magnitude of changes in cellular and molecular markers of anabolic and myogenic responses were similar in the OL-Ir and the contralateral nonirradiated, overloaded (OL) muscles for the first 3-7 days. These markers then returned to control levels in OL-Ir muscles while remaining elevated in OL muscles. The number of myonuclei and amount of DNA were increased markedly in OL but not OL-Ir muscles. Thus it appears that stem cells were not added to the irradiated muscles in this time period. These data are consistent with the theory that the addition of new myonuclei may be required for compensatory hypertrophy in the rat.

  18. A mathematical framework for separating the direct and bystander components of cellular radiation response

    International Nuclear Information System (INIS)

    A mathematical model for fractional tumor cell survival was developed incorporating components of cell killing due to direct radiation interactions and bystander signals resulting from non-local dose deposition. Material and methods. Three possible mechanisms for signal production were tested by fitting predictions to available experimental results for tumor cells (non-small cell lung cancer NCI-H460 and melanoma MM576) exposed to gradient x-ray fields. The parameter fitting allowed estimation of the contribution of bystander signaling to cell death (20-50% for all models). Separation of the two components of cell killing allowed determination of the α and β parameters of the linear-quadratic model both with and without the presence of bystander signaling. Results and discussion. For both cell lines, cell death from bystander signaling and direct radiation interactions were comparable. For NCI-H460 cells, the values for α and β were 0.18 Gy-1 and 0.10 Gy-2 respectively when direct and bystander effects were combined, and 0.053 Gy-1 and 0.061 Gy-2 respectively when the signaling component was removed. For MM576, the corresponding respective values were 0.09 Gy-1 and 0.011 Gy-2 for the combined response, and 0.014 Gy-1 and 0.002 Gy-2 for the isolated direct radiation response. The bystander component in cell death was found to be significant and should not be ignored. Further experimental evidence is required to determine how these results translate to the in vivo situation where tumor control probability (TCP) models that currently assume cellular independence may need to be revised

  19. A mathematical framework for separating the direct and bystander components of cellular radiation response

    Energy Technology Data Exchange (ETDEWEB)

    Ebert, Martin A. (Dept. of Radiation Oncology, Sir Charles Gairdner Hospital, Western Australia (Australia)), E-mail: Martin.Ebert@health.wa.gov.au; Suchowerska, Natalka; Jackson, Michael A. (Dept. of Radiation Oncology, Royal Prince Alfred Hospital, New South Wales (Australia)); McKenzie, David R. (School of Physics, Univ. of Sydney, New South Wales (Australia))

    2010-11-15

    A mathematical model for fractional tumor cell survival was developed incorporating components of cell killing due to direct radiation interactions and bystander signals resulting from non-local dose deposition. Material and methods. Three possible mechanisms for signal production were tested by fitting predictions to available experimental results for tumor cells (non-small cell lung cancer NCI-H460 and melanoma MM576) exposed to gradient x-ray fields. The parameter fitting allowed estimation of the contribution of bystander signaling to cell death (20-50% for all models). Separation of the two components of cell killing allowed determination of the alpha and beta parameters of the linear-quadratic model both with and without the presence of bystander signaling. Results and discussion. For both cell lines, cell death from bystander signaling and direct radiation interactions were comparable. For NCI-H460 cells, the values for alpha and beta were 0.18 Gy-1 and 0.10 Gy-2 respectively when direct and bystander effects were combined, and 0.053 Gy-1 and 0.061 Gy-2 respectively when the signaling component was removed. For MM576, the corresponding respective values were 0.09 Gy-1 and 0.011 Gy-2 for the combined response, and 0.014 Gy-1 and 0.002 Gy-2 for the isolated direct radiation response. The bystander component in cell death was found to be significant and should not be ignored. Further experimental evidence is required to determine how these results translate to the in vivo situation where tumor control probability (TCP) models that currently assume cellular independence may need to be revised

  20. Single-cell bioelectrical impedance platform for monitoring cellular response to drug treatment

    International Nuclear Information System (INIS)

    The response of cells to a chemical or biological agent in terms of their impedance changes in real-time is a useful mechanism that can be utilized for a wide variety of biomedical and environmental applications. The use of a single-cell-based analytical platform could be an effective approach to acquiring more sensitive cell impedance measurements, particularly in applications where only diminutive changes in impedance are expected. Here, we report the development of an on-chip cell impedance biosensor with two types of electrodes that host individual cells and cell populations, respectively, to study its efficacy in detecting cellular response. Human glioblastoma (U87MG) cells were patterned on single- and multi-cell electrodes through ligand-mediated natural cell adhesion. We comparatively investigated how these cancer cells on both types of electrodes respond to an ion channel inhibitor, chlorotoxin (CTX), in terms of their shape alternations and impedance changes to exploit the fine detectability of the single-cell-based system. The detecting electrodes hosting single cells exhibited a significant reduction in the real impedance signal, while electrodes hosting confluent monolayer of cells showed little to no impedance change. When single-cell electrodes were treated with CTX of different doses, a dose-dependent impedance change was observed. This enables us to identify the effective dose needed for this particular treatment. Our study demonstrated that this single-cell impedance system may potentially serve as a useful analytical tool for biomedical applications such as environmental toxin detection and drug evaluation

  1. Cellular Immune Response of Weaned Pigs Fed Diet Supplemented with an Essential Oil

    Directory of Open Access Journals (Sweden)

    János Tossenberger

    2011-10-01

    Full Text Available The objective of the present study was to investigate the effect of an essential oil product on growth performance and cellular immune response of 28-day-old weaned piglets. A total of 348 piglets (50% gilts, 50% barrows were assigned to three dietary treatments (6 pens/trt. Th e basal diet was a commercial feed that was supplemented without any growth promoter (NC, with antibiotic growth promoter of 40 ppm avilamycin (PC, or with 0.25 g of an essential oil product (EO per kg of feed. All pigs were immunized by inactivated Aujeszky’s disease virus vaccine at week one and three of the experiment (28- and 44-days-age, respectively. Blood samples were taken four times (on day one, 16, 24, 32 of the experiment for lymphocyte stimulation (LST tests with ConA, PWM, PHA used as non-specific and Aujeszky virus used as specific mitogens from 2 pigs/pen. All piglets were individually weighed on day 0, 8, 16, 24 and 32 of the trial.There was no significant difference among average daily gain, feed intake and feed conversion ratio of piglets fed different dietary treatments. The non-specific LST test at the 4th blood sampling showed higher values in pigs received feeds with essential oil supplementation (EO than that of the positive (PC and negative control (NC groups (P<0.05. However, no significant difference in specific immune response of pigs in different dietary treatments was found. It can be concluded that essential oil supplementation may enhance the non-specific immunocompetence of 28-day-old weaning pigs without compromising their growth performance.

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

    International Nuclear Information System (INIS)

    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.

  3. Substance P: binding properties and studies on cellular responses in guinea pig macrophages

    International Nuclear Information System (INIS)

    The neuropeptide Substance P (SP) has been recognized to modulate functional activities of inflammatory cells. The authors have previously shown that it mediates macrophage activation. In this study they examined binding characteristics of SP and searched for additional evidence of heightened metabolic activity of guinea pig peritoneal macrophages upon challenge with this peptide. Radioligand studies indicated the existence of a homogeneous class of specific binding sites with high affinity for SP on macrophages. Scatchard analysis yielded an apparent K/sub D/ of 1.9 +/- 0.4 x 10-8 M (range: 1.4 to 2.4 x 10-8 M), which was confirmed by kinetic studies. Binding was dose related, saturable, reversible, and could be inhibited by the SP antagonist (D-Pro2, D-Phe7, D-Trp9)-SP. Examination of peptide structural requirements revealed that both the COOH- and NH2-terminus contribute to receptor-ligand interaction. Other members of the tachykinin group of peptides were devoid of stimulatory action on macrophages. Cellular responses after engagement of the receptor sites by SP included downregulation of the membrane-associated enzyme 5'-nucleotidase and stimulation of synthesis and release of arachidonic acid metabolites, as well as of the lysosomal enzyme ADGase. These actions were specific as evidenced by immunoabsorption experiments. The findings demonstrate that macrophage activation afforded by SP is effected through a receptor-mediated mechanism. Liberation of proinflammatory and immunomodulating substances in response to SP may be relevant to the pathogenesis of neuroinflammatory disease

  4. Effects of acclimation temperature and cadmium exposure on cellular energy budgets in the marine mollusk Crassostrea virginica: linking cellular and mitochondrial responses.

    Science.gov (United States)

    Cherkasov, Anton S; Biswas, Pradip K; Ridings, Daisy M; Ringwood, Amy H; Sokolova, Inna M

    2006-04-01

    In order to understand the role of metabolic regulation in environmental stress tolerance, a comprehensive analysis of demand-side effects (i.e. changes in energy demands for basal maintenance) and supply-side effects (i.e. metabolic capacity to provide ATP to cover the energy demand) of environmental stressors is required. We have studied the effects of temperature (12, 20 and 28 degrees C) and exposure to a trace metal, cadmium (50 microg l(-1)), on the cellular energy budget of a model marine poikilotherm, Crassostrea virginica (eastern oysters), using oxygen demand for ATP turnover, protein synthesis, mitochondrial proton leak and non-mitochondrial respiration in isolated gill and hepatopancreas cells as demand-side endpoints and mitochondrial oxidation capacity, abundance and fractional volume as supply-side endpoints. Cadmium exposure and high acclimation temperatures resulted in a strong increase of oxygen demand in gill and hepatopancreas cells of oysters. Cd-induced increases in cellular energy demand were significant at 12 and 20 degrees C but not at 28 degrees C, possibly indicating a metabolic capacity limitation at the highest temperature. Elevated cellular demand in cells from Cd-exposed oysters was associated with a 2-6-fold increase in protein synthesis and, at cold acclimation temperatures, with a 1.5-fold elevated mitochondrial proton leak. Cellular aerobic capacity, as indicated by mitochondrial oxidation capacity, abundance and volume, did not increase in parallel to compensate for the elevated energy demand. Mitochondrial oxidation capacity was reduced in 28 degrees C-acclimated oysters, and mitochondrial abundance decreased in Cd-exposed oysters, with a stronger decrease (by 20-24%) in warm-acclimated oysters compared with cold-acclimated ones (by 8-13%). These data provide a mechanistic basis for synergism between temperature and cadmium stress on metabolism of marine poikilotherms. Exposure to combined temperature and cadmium stress may

  5. The Cellular Prion Protein Prevents Copper-Induced Inhibition of P2X4 Receptors

    Directory of Open Access Journals (Sweden)

    Ramón A. Lorca

    2011-01-01

    Full Text Available Although the physiological function of the cellular prion protein (PrPC remains unknown, several evidences support the notion of its role in copper homeostasis. PrPC binds Cu2+ through a domain composed by four to five repeats of eight amino acids. Previously, we have shown that the perfusion of this domain prevents and reverses the inhibition by Cu2+ of the adenosine triphosphate (ATP-evoked currents in the P2X4 receptor subtype, highlighting a modulatory role for PrPC in synaptic transmission through regulation of Cu2+ levels. Here, we study the effect of full-length PrPC in Cu2+ inhibition of P2X4 receptor when both are coexpressed. PrPC expression does not significantly change the ATP concentration-response curve in oocytes expressing P2X4 receptors. However, the presence of PrPC reduces the inhibition by Cu2+ of the ATP-elicited currents in these oocytes, confirming our previous observations with the Cu2+ binding domain. Thus, our observations suggest a role for PrPC in modulating synaptic activity through binding of extracellular Cu2+.

  6. 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...

  7. New TLR7 agonists with improved humoral and cellular immune responses.

    Science.gov (United States)

    Upchurch, Katherine C; Boquín, José R; Yin, Wenjie; Xue, Yaming; Joo, HyeMee; Kane, Robert R; Oh, SangKon

    2015-11-01

    Toll-like receptor 7 (TLR7) agonists are of interest as vaccine adjuvants and cancer therapeutics. Therefore, development of new TLR7 agonists that can efficiently promote host immune responses without evoking side effects is of great importance. Here, we describe two new compounds, J4 and F4, which elicit intracellular signaling exclusively via TLR7. Interestingly, both J4 and F4 induced less cytokine secretion (IL-1β, IL-6, IL-10, IL-12p40, TNFα, and IL-12p70) from myeloid dendritic cells (mDCs) and monocytes than CL075 and R848; however, they all generated similar levels of phenotype maturation of antigen presenting cells (APCs), including plasmacytoid DCs. We further found that J4- and F4-induced APC activation was largely dependent on the activation of NF-κB and p38. Lastly, J4 and F4 could efficiently promote B cell proliferation and plasmablast differentiation as well as antigen-specific CD8(+) T cell responses in human in vitro. Therefore, these new TLR7 agonists could be employed to facilitate the development of new therapeutics and vaccine adjuvants against cancers and microbial infections. PMID:26381186

  8. 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

  9. Exercise-induced ROS in heat shock proteins response.

    Science.gov (United States)

    Dimauro, Ivan; Mercatelli, Neri; Caporossi, Daniela

    2016-09-01

    Cells have evolved multiple and sophisticated stress response mechanisms aiming to prevent macromolecular (including proteins, lipids, and nucleic acids) damage and to maintain or re-establish cellular homeostasis. Heat shock proteins (HSPs) are among the most highly conserved, ubiquitous, and abundant proteins in all organisms. Originally discovered more than 50 years ago through heat shock stress, they display multiple, remarkable roles inside and outside cells under a variety of stresses, including also oxidative stress and radiation, recognizing unfolded or misfolded proteins and facilitating their restructuring. Exercise consists in a combination of physiological stresses, such as metabolic disturbances, changes in circulating levels of hormones, increased temperature, induction of mild to severe inflammatory state, increased production of reactive oxygen and nitrogen species (ROS and RNS). As a consequence, exercise is one of the main stimuli associated with a robust increase in different HSPs in several tissues, which appears to be also fundamental in facilitating the cellular remodeling processes related to the training regime. Among all factors involved in the exercise-related modulation of HSPs level, the ROS production in the contracting muscle or in other tissues represents one of the most attracting, but still under discussion, mechanism. Following exhaustive or damaging muscle exercise, major oxidative damage to proteins and lipids is likely involved in HSP expression, together with mechanically induced damage to muscle proteins and the inflammatory response occurring several days into the recovery period. Instead, the transient and reversible oxidation of proteins by physiological concentrations of ROS seems to be involved in the activation of stress response following non-damaging muscle exercise. This review aims to provide a critical update on the role of HSPs response in exercise-induced adaptation or damage in humans, focusing on experimental

  10. Derepression of hTERT gene expression promotes escape from oncogene-induced cellular senescence.

    Science.gov (United States)

    Patel, Priyanka L; Suram, Anitha; Mirani, Neena; Bischof, Oliver; Herbig, Utz

    2016-08-23

    Oncogene-induced senescence (OIS) is a critical tumor-suppressing mechanism that restrains cancer progression at premalignant stages, in part by causing telomere dysfunction. Currently it is unknown whether this proliferative arrest presents a stable and therefore irreversible barrier to cancer progression. Here we demonstrate that cells frequently escape OIS induced by oncogenic H-Ras and B-Raf, after a prolonged period in the senescence arrested state. Cells that had escaped senescence displayed high oncogene expression levels, retained functional DNA damage responses, and acquired chromatin changes that promoted c-Myc-dependent expression of the human telomerase reverse transcriptase gene (hTERT). Telomerase was able to resolve existing telomeric DNA damage response foci and suppressed formation of new ones that were generated as a consequence of DNA replication stress and oncogenic signals. Inhibition of MAP kinase signaling, suppressing c-Myc expression, or inhibiting telomerase activity, caused telomere dysfunction and proliferative defects in cells that had escaped senescence, whereas ectopic expression of hTERT facilitated OIS escape. In human early neoplastic skin and breast tissue, hTERT expression was detected in cells that displayed features of senescence, suggesting that reactivation of telomerase expression in senescent cells is an early event during cancer progression in humans. Together, our data demonstrate that cells arrested in OIS retain the potential to escape senescence by mechanisms that involve derepression of hTERT expression. PMID:27503890

  11. PTH1 receptor is involved in mediating cellular response to long-chain polyunsaturated fatty acids.

    Directory of Open Access Journals (Sweden)

    Jose Candelario

    Full Text Available The molecular pathways by which long chain polyunsaturated fatty acids (LCPUFA influence skeletal health remain elusive. Both LCPUFA and parathyroid hormone type 1 receptor (PTH1R are known to be involved in bone metabolism while any direct link between the two is yet to be established. Here we report that LCPUFA are capable of direct, PTH1R dependent activation of extracellular ligand-regulated kinases (ERK. From a wide range of fatty acids studied, varying in chain length, saturation, and position of double bonds, eicosapentaenoic (EPA and docosahexaenoic fatty acids (DHA caused the highest ERK phosphorylation. Moreover, EPA potentiated the effect of parathyroid hormone (PTH(1-34 in a superagonistic manner. EPA or DHA dependent ERK phosphorylation was inhibited by the PTH1R antagonist and by knockdown of PTH1R. Inhibition of PTH1R downstream signaling molecules, protein kinases A (PKA and C (PKC, reduced EPA and DHA dependent ERK phosphorylation indicating that fatty acids predominantly activate G-protein pathway and not the β-arrestin pathway. Using picosecond time-resolved fluorescence microscopy and a genetically engineered PTH1R sensor (PTH-CC, we detected conformational responses to EPA similar to those caused by PTH(1-34. PTH1R antagonist blocked the EPA induced conformational response of the PTH-CC. Competitive binding studies using fluorescence anisotropy technique showed that EPA and DHA competitively bind to and alter the affinity of PTH1 receptor to PTH(1-34 leading to a superagonistic response. Finally, we showed that EPA stimulates protein kinase B (Akt phosphorylation in a PTH1R-dependent manner and affects the osteoblast survival pathway, by inhibiting glucocorticoid-induced cell death. Our findings demonstrate for the first time that LCPUFAs, EPA and DHA, can activate PTH1R receptor at nanomolar concentrations and consequently provide a putative molecular mechanism for the action of fatty acids in bone.

  12. Potential Mechanisms for Cancer Resistance in Elephants and Comparative Cellular Response to DNA Damage in Humans

    Science.gov (United States)

    Abegglen, Lisa M.; Caulin, Aleah F.; Chan, Ashley; Lee, Kristy; Robinson, Rosann; Campbell, Michael S.; Kiso, Wendy K.; Schmitt, Dennis L.; Waddell, Peter J; Bhaskara, Srividya; Jensen, Shane T.; Maley, Carlo C.; Schiffman, Joshua D.

    2016-01-01

    IMPORTANCE Evolutionary medicine may provide insights into human physiology and pathophysiology, including tumor biology. OBJECTIVE To identify mechanisms for cancer resistance in elephants and compare cellular response to DNA damage among elephants, healthy human controls, and cancer-prone patients with Li-Fraumeni syndrome (LFS). DESIGN, SETTING, AND PARTICIPANTS A comprehensive survey of necropsy data was performed across 36 mammalian species to validate cancer resistance in large and long-lived organisms, including elephants (n = 644). The African and Asian elephant genomes were analyzed for potential mechanisms of cancer resistance. Peripheral blood lymphocytes from elephants, healthy human controls, and patients with LFS were tested in vitro in the laboratory for DNA damage response. The study included African and Asian elephants (n = 8), patients with LFS (n = 10), and age-matched human controls (n = 11). Human samples were collected at the University of Utah between June 2014 and July 2015. EXPOSURES Ionizing radiation and doxorubicin. MAIN OUTCOMES AND MEASURES Cancer mortality across species was calculated and compared by body size and life span. The elephant genome was investigated for alterations in cancer-related genes. DNA repair and apoptosis were compared in elephant vs human peripheral blood lymphocytes. RESULTS Across mammals, cancer mortality did not increase with body size and/or maximum life span (eg, for rock hyrax, 1% [95%CI, 0%–5%]; African wild dog, 8%[95%CI, 0%–16%]; lion, 2%[95%CI, 0% –7%]). Despite their large body size and long life span, elephants remain cancer resistant, with an estimated cancer mortality of 4.81% (95%CI, 3.14%–6.49%), compared with humans, who have 11% to 25%cancer mortality. While humans have 1 copy (2 alleles) of TP53, African elephants have at least 20 copies (40 alleles), including 19 retrogenes (38 alleles) with evidence of transcriptional activity measured by reverse transcription polymerase chain

  13. Detection, characterization and measure of a new radiation-induced damage in isolated and cellular DNA

    International Nuclear Information System (INIS)

    Deoxyribonucleic acid (DNA) contains the genetic information and chemical injury to this macromolecule may have severe biological consequences. We report here the detection of 4 new radiation-induced DNA lesions by using a high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) approach. For that purpose, the characteristic fragmentation of most 2'-deoxy-ribo nucleosides, the loss of 116 Da corresponding to the loss of the 2-deoxyribose moiety, was used in the so-called neutral loss mode of the HPLC-MS/MS. One of the newly detected lesions, named dCyd341 because it is a 2'-deoxycytidine modification exhibiting a molecular weight of 341 Da, was also detected in cellular DNA. Characterization of this modified nucleoside was performed using NMR and exact mass determination of the product obtained by chemical synthesis. A mechanism of formation was then proposed, in which the first event is the H-abstraction at the C4 position of a 2-deoxyribose moiety. Then, the sugar modification produced exhibits a reactive aldehyde that, through reaction with a vicinal cytosine base, gives rise to dCyd341. dCyd341 could be considered as a complex damage since its formation involves a DNA strand break and a cross-link between a damaged sugar residue and a vicinal cytosine base located most probably on the complementary DNA strand. In addition to its characterization, preliminary biological studies revealed that cells are able to remove the lesion from DNA. Repair studies have revealed the ability of cells to excise the lesion. Identification of the repair systems involved could represent an interesting challenge. (author)

  14. Lung damage induced by butylated hydroxytoluene in mice. Biochemical, cellular, and morphologic characterization.

    Science.gov (United States)

    Smith, L J

    1984-11-01

    This study was designed to characterize the biochemical, cellular, and morphologic events produced in mice by butylated hydroxytoluene (BHT) and to relate these events to changes in extracellular angiotensin-converting enzyme (ACE) activity. On Day 1 after the administration of BHT, bronchoalveolar lavage (BAL) ACE activity increased 4-fold (p less than 0.001), its specific activity relative to BAL protein increased 3-fold (p less than 0.001), and both type 1 cell damage and endothelial cell damage were detected by electron microscopy. The early increase in BAL ACE activity preceded changes in plasma ACE levels, BAL cell number, protein, lactate, and lactate dehydrogenase (LDH) activity in both plasma and BAL, and the ACE content of alveolar macrophages. On Day 2, BAL ACE activity increased 9-fold, BAL protein increased 4-fold (p less than 0.001), BAL LDH activity increased 34% (p less than 0.05), and the BAL cell count doubled (p less than 0.01). Changes in each animal's appearance, body weight, wet and dry lung weights, and plasma ACE levels occurred between Days 3 and 5. The BAL differential cell count, which consisted of greater than 95% macrophages in uninjured mice, did not change until Day 5 when there was a small increase in polymorphonuclear leukocytes (PMN). On Day 7, the number of PMN peaked, and some of the other measures of lung injury began returning toward normal. These results indicate that BAL ACE activity is a sensitive, early marker of BHT-induced lung injury, which appears to reflect damage to the cells of the alveolar-capillary barrier. In addition, PMN do not appear to play a major role in this model of lung injury. Because of its effects on angiotensin, bradykinin, and prostaglandins, the early release of ACE from damaged cells may modulate the subsequent injury. PMID:6093659

  15. Atomic force microscopic neutron-induced alpha-autoradiography for boron imaging in detailed cellular histology

    International Nuclear Information System (INIS)

    The information on subcellular microdistribution of 10B compounds a cell is significant to evaluate the efficacy of boron neutron capture therapy (BNCT) because the damage brought by the released alpha/lithium particles is highly localized along their path, and radiation sensitivity is quite different among each cell organelles. In neutron-induced alpha-autoradiography (NIAR) technique, 10B can be measured as tracks for the energetic charged particles from 10B(n, alpha)7Li reactions in solid state track detectors. To perform the NIAR at intracellular structure level for research of 10B uptake and/or microdosimetry in BNCT, we have developed high-resolution NIAR method with an atomic force microscope (AFM). AFM has been used for analyses of biological specimens such as proteins, DNAs and surface of living cells have, however, intracellular detailed histology of cells has been hardly resolved with AFM since flat surface of sectioned tissue has quite less topographical contrast among each organelle. In our new sample preparation method using UV processing, materials that absorb UV in a semi-thin section are selectively eroded and vaporized by UV exposure, and then fine relief for cellular organelles such as mitochondria, endoplasmic reticulum, filament structure and so on reveals on flat surface of the section, which can be observed with an AFM. The imaging resolution was comparable to TEM imaging of cells. This new method provides fast and cost-effective observation of histological sections with an AFM. Combining this method with NIAR technique, intracellular boron mapping would be possible. (author)

  16. Acute dyskerin depletion triggers cellular senescence and renders osteosarcoma cells resistant to genotoxic stress-induced apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Ping; Mobasher, Maral E.; Alawi, Faizan, E-mail: falawi@upenn.edu

    2014-04-18

    Highlights: • Dyskerin depletion triggers cellular senescence in U2OS osteosarcoma cells. • Dyskerin-depleted cells are resistant to apoptosis induced by genotoxic stress. • Chromatin relaxation sensitizes dyskerin-depleted cells to apoptosis. - Abstract: Dyskerin is a conserved, nucleolar RNA-binding protein implicated in an increasing array of fundamental cellular processes. Germline mutation in the dyskerin gene (DKC1) is the cause of X-linked dyskeratosis congenita (DC). Conversely, wild-type dyskerin is overexpressed in sporadic cancers, and high-levels may be associated with poor prognosis. It was previously reported that acute loss of dyskerin function via siRNA-mediated depletion slowed the proliferation of transformed cell lines. However, the mechanisms remained unclear. Using human U2OS osteosarcoma cells, we show that siRNA-mediated dyskerin depletion induced cellular senescence as evidenced by proliferative arrest, senescence-associated heterochromatinization and a senescence-associated molecular profile. Senescence can render cells resistant to apoptosis. Conversely, chromatin relaxation can reverse the repressive effects of senescence-associated heterochromatinization on apoptosis. To this end, genotoxic stress-induced apoptosis was suppressed in dyskerin-depleted cells. In contrast, agents that induce chromatin relaxation, including histone deacetylase inhibitors and the DNA intercalator chloroquine, sensitized dyskerin-depleted cells to apoptosis. Dyskerin is a core component of the telomerase complex and plays an important role in telomere homeostasis. Defective telomere maintenance resulting in premature senescence is thought to primarily underlie the pathogenesis of X-linked DC. Since U2OS cells are telomerase-negative, this leads us to conclude that loss of dyskerin function can also induce cellular senescence via mechanisms independent of telomere shortening.

  17. Assessment of cellular immune responses of healthy and diseased Tasmanian devils (Sarcophilus harrisii).

    Science.gov (United States)

    Kreiss, Alexandre; Fox, Nolan; Bergfeld, Jemma; Quinn, Stephen J; Pyecroft, Stephen; Woods, Gregory M

    2008-01-01

    The Tasmanian devil (TD) (Sarcophilus harrisii) is under threat from devil facial tumour disease (DFTD), a cancer that is transmitted between devils by direct cell implantation. As no devil is known to have rejected the tumour allograft, an understanding of the immune status of this species is essential to help explain the unique infectious nature of this cancer. We analysed differential white blood cell counts, the phagocytic response of neutrophils as well as mitogen-induced lymphocyte proliferation. Devils analysed included healthy TDs kept in captivity, healthy devils from disease-free and diseased areas as well as diseased devils. Neutrophils isolated from the peripheral blood of healthy devils showed competent phagocytosis and peripheral blood mononuclear cells from healthy and diseased devils proliferated in response to Con A, PHA and PWM stimulation. Although a wide range of responses was observed and relatively high doses of mitogens were required, there was no significant difference between males and females, adults and juveniles or between normal and diseased animals, suggesting that transmission of DFTD is not a consequence of a severely impaired immune system. As lymphocytes from all TDs appear to require strong stimulation for activation, this threshold may contribute to all devils being susceptible to DFTD. PMID:17988737

  18. Nitric oxide produced endogenously is responsible for hypoxia-induced HIF-1α stabilization in colon carcinoma cells

    OpenAIRE

    Chowdhury, Rajdeep; Godoy, Luiz C.; Thiantanawat, Apinya; Trudel, Laura J.; Deen, William M.; Wogan, Gerald N.

    2012-01-01

    Hypoxia-inducible factor-1 alpha (HIF-1α) is a critical regulator of cellular responses to hypoxia. Under normoxic conditions, cellular HIF-1α level is regulated by hydroxylation by prolyl hydroxylases (PHDs), ubiquitylation and proteasomal degradation. During hypoxia, degradation decreases and its intracellular level is increased. Exogenously administered nitric oxide (NO)-donor drugs stabilize HIF-1α, and thus NO is suggested to mimic hypoxia. However, the role of low levels of endogenously...

  19. Mechanisms underlying cellular responses of cells from haemopoietic tissue to low dose/low LET radiation

    Energy Technology Data Exchange (ETDEWEB)

    Munira A Kadhim

    2010-03-05

    To accurately define the risks associated with human exposure to relevant environmental doses of low LET ionizing radiation, it is necessary to completely understand the biological effects at very low doses (i.e., less than 0.1 Gy), including the lowest possible dose, that of a single electron track traversal. At such low doses, a range of studies have shown responses in biological systems which are not related to the direct interaction of radiation tracks with DNA. The role of these “non-targeted” responses in critical tissues is poorly understood and little is known regarding the underlying mechanisms. Although critical for dosimetry and risk assessment, the role of individual genetic susceptibility in radiation risk is not satisfactorily defined at present. The aim of the proposed grant is to critically evaluate radiation-induced genomic instability and bystander responses in key stem cell populations from haemopoietic tissue. Using stem cells from two mouse strains (CBA/H and C57BL/6J) known to differ in their susceptibility to radiation effects, we plan to carefully dissect the role of genetic predisposition on two non-targeted radiation responses in these models; the bystander effect and genomic instability, which we believe are closely related. We will specifically focus on the effects of low doses of low LET radiation, down to doses approaching a single electron traversal. Using conventional X-ray and γ-ray sources, novel dish separation and targeted irradiation approaches, we will be able to assess the role of genetic variation under various bystander conditions at doses down to a few electron tracks. Irradiations will be carried out using facilities in routine operation for bystander targeted studies. Mechanistic studies of instability and the bystander response in different cell lineages will focus initially on the role of cytokines which have been shown to be involved in bystander signaling and the initiation of instability. These studies also aim

  20. Fire-Induced Response in Foam Encapsulants

    Energy Technology Data Exchange (ETDEWEB)

    Borek, T.T.; Chu, T.Y.; Erickson, K.L.; Gill, W.; Hobbs, M.L.; Humphries, L.L.; Renlund, A.M.; Ulibarri, T.A.

    1999-04-02

    The paper provides a concise overview of a coordinated experimental/theoretical/numerical program at Sandia National Laboratories to develop an experimentally validated model of fire-induced response of foam-filled engineered systems for nuclear and transportation safety applications. Integral experiments are performed to investigate the thermal response of polyurethane foam-filled systems exposed to fire-like heat fluxes. A suite of laboratory experiments is performed to characterize the decomposition chemistry of polyurethane. Mass loss and energy associated with foam decomposition and chemical structures of the virgin and decomposed foam are determined. Decomposition chemistry is modeled as the degradation of macromolecular structures by bond breaking followed by vaporization of small fragments of the macromolecule with high vapor pressures. The chemical decomposition model is validated against the laboratory data. Data from integral experiments is used to assess and validate a FEM foam thermal response model with the chemistry model developed from the decomposition experiments. Good agreement was achieved both in the progression of the decomposition front and the in-depth thermal response.

  1. Microstructures, mechanical behavior, cellular response, and hemocompatibility of bulk ultrafine-grained pure tantalum.

    Science.gov (United States)

    Nie, F L; Zheng, Y F; Wang, Y; Wang, J T

    2014-02-01

    Bulk ultrafine-grained (UFG) pure Ta had been successfully prepared by equal channel angular pressing (ECAP) technique till eight passes. The 1st, 2nd, 4th, and 8th ECAPed Ta samples were investigated in the current study, with the 0th ECAPed Ta sample as the microcrystalline counterpart control. The microstructure and grain size distribution were characterized by X-ray diffractometer patterns, scanning electron microscopy, and transmission electron microscopy analysis by means of histogram. Although the mechanical behavior of all the experimental samples were analyzed through uniaxial tensile measurement and microhardness test, in vitro biological interactions onto the substrates such as protein adsorption, cellular responses derived from different types of cell lines, and the activity of erythrocyte and platelets were further evaluated and specifically assessed by bicinchoninic acid assay, enzyme-linked immunosorbent assay, and the method of colorimetric reading. A superior percentage of protein adsorption can be observed on the substrate of the UFG 8th ECAPed Ta (around 90%), even above those on the tissue culture plate (control) and the other ECAPed Ta samples. Furthermore, the UFG 8th ECAPed Ta shows no cytotoxic within 4 days culture when incubated with the murine fibroblast cell lines (L929). In addition, a priority order in the growth of endothelial cells (ECV304) other than vascular smooth muscle cells was observed in the case of the UFG 8th ECAPed Ta. In terms of hemolysis rate and adhered platelets (both the amount and the individual morphology), an evolutionary outcome of preferentially enhanced hemocompatibility can be concluded for the case of the UFG 8th ECAPed Ta. PMID:23908098

  2. Visfatin induces sickness responses in the brain.

    Directory of Open Access Journals (Sweden)

    Byong Seo Park

    Full Text Available BACKGROUND/OBJECTIVE: Visfatin, also known as nicotiamide phosphoribosyltransferase or pre-B cell colony enhancing factor, is a pro-inflammatory cytokine whose serum level is increased in sepsis and cancer as well as in obesity. Here we report a pro-inflammatory role of visfatin in the brain, to mediate sickness responses including anorexia, hyperthermia and hypoactivity. METHODOLOGY: Rats were intracerebroventricularly (ICV injected with visfatin, and changes in food intake, body weight, body temperature and locomotor activity were monitored. Real-time PCR was applied to determine the expressions of pro-inflammatory cytokines, proopiomelanocortin (POMC and prostaglandin-synthesizing enzymes in their brain. To determine the roles of cyclooxygenase (COX and melanocortin in the visfatin action, rats were ICV-injected with visfatin with or without SHU9119, a melanocortin receptor antagonist, or indomethacin, a COX inhibitor, and their sickness behaviors were evaluated. PRINCIPAL FINDINGS: Administration of visfatin decreased food intake, body weight and locomotor activity and increased body temperature. Visfatin evoked significant increases in the levels of pro-inflammatory cytokines, prostaglandin-synthesizing enzymes and POMC, an anorexigenic neuropeptide. Indomethacin attenuated the effects of visfatin on hyperthermia and hypoactivity, but not anorexia. Further, SHU9119 blocked visfatin-induced anorexia but did not affect hyperthermia or hypoactivity. CONCLUSIONS: Visfatin induced sickness responses via regulation of COX and the melanocortin pathway in the brain.

  3. Viral oncogene-induced DNA damage response is activated in Kaposi sarcoma tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Sonja Koopal

    2007-09-01

    Full Text Available Kaposi sarcoma is a tumor consisting of Kaposi sarcoma herpesvirus (KSHV-infected tumor cells that express endothelial cell (EC markers and viral genes like v-cyclin, vFLIP, and LANA. Despite a strong link between KSHV infection and certain neoplasms, de novo virus infection of human primary cells does not readily lead to cellular transformation. We have studied the consequences of expression of v-cyclin in primary and immortalized human dermal microvascular ECs. We show that v-cyclin, which is a homolog of cellular D-type cyclins, induces replicative stress in ECs, which leads to senescence and activation of the DNA damage response. We find that antiproliferative checkpoints are activated upon KSHV infection of ECs, and in early-stage but not late-stage lesions of clinical Kaposi sarcoma specimens. These are some of the first results suggesting that DNA damage checkpoint response also functions as an anticancer barrier in virally induced cancers.

  4. Establishing cellular stress response profiles as biomarkers of homeodynamics, health, and hormesis

    DEFF Research Database (Denmark)

    Demirovic, Dino; Rattan, Suresh

    2013-01-01

    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 be established at several age-points, which can be the molecular biomarkers of homeodynamic space and...... effective strategy, which makes use of SRP for achieving healthy aging and extending the healthspan, is that of strengthening the homeodynamics through repeated mild stress-induced hormesis by physical, biological and nutritional hormetins. Furthermore, SRP can also be the basis for defining health as a...... state of having adequate physical and mental independence of activities of daily living, by identifying a set of measurable parameters at the most fundamental level of biological organization....

  5. Physiological and Cytological Similarities between Disease Resistance and Cellular Incompatibility Responses.

    Science.gov (United States)

    Teasdale, J; Daniels, D; Davis, W C; Eddy, R; Hadwiger, L A

    1974-11-01

    Excised pea pods responded similarly to both the invasion of plant pathogenic fungi and the presence of bean tissue, bean pollen, and mouse tumor cells by synthesizing pisatin and by developing a characteristic yellow-green fluorescence. Both responses were dependent on RNA and protein synthesis. Conversely, the foreign pollen and incompatible fungi were sensitive to the pea pod tissue and were subject to abnormal development.The induction of pisatin and the yellow-green fluorescence development were mediated by multiple compounds of varying sizes released by fungi or mouse tumor cells. The incompatibility between a bean pathogen, Fusarium solani f. sp. phaseoli, and pea pod tissue was hypothesized to occur as a result of the cross contamination of such inducing compounds. PMID:16658953

  6. DNMT3a epigenetic program regulates the HIF-2α oxygen-sensing pathway and the cellular response to hypoxia

    OpenAIRE

    Lachance, Gabriel; Uniacke, James; Audas, Timothy E.; Holterman, Chet E.; Franovic, Aleksandra; Payette, Josianne; Lee, Stephen

    2014-01-01

    DNA methyltransferase 3a (DNMT3a) mediates the de novo methylation of DNA to regulate gene expression and maintain cellular homeostasis. Mutations in DNMT3a in primary tumors suggest that the DNMT3a epigenetic program is modified during early tumorigenesis. We show that a major consequence of DNMT3a defects is the epigenetic deregulation and unscheduled activation of the EPAS1 (hypoxia-inducible factor 2α) gene that facilitates growth and viability under conditions of low oxygen availability....

  7. Identification of PM10 characteristics involved in cellular responses in human bronchial epithelial cells (Beas-2B).

    Science.gov (United States)

    Van Den Heuvel, Rosette; Den Hond, Elly; Govarts, Eva; Colles, Ann; Koppen, Gudrun; Staelens, Jeroen; Mampaey, Maja; Janssen, Nicole; Schoeters, Greet

    2016-08-01

    reduction in cell viability was significantly correlated with BC, Cd and Pb. The induction of IL-8 in Beas-2B cells was significantly associated with Cu, Ni and Zn and endotoxin. Endotoxin levels explained 33% of the variance in IL-8 induction. A significant interaction between ambient temperature and endotoxin on the pro-inflammatory activity was seen. No association was found between OP and the cellular responses. This study supports the hypothesis that, on an equal mass basis, PM10 induced biological effects differ due to differences in PM10 characteristics. Metals (Cd, Cu, Ni and Zn), BC, and endotoxin were among the main determinants for the observed biological responses. PMID:27177354

  8. Cellular adaptive immune response against porcine circovirus type 2 in subclinically infected pigs

    Directory of Open Access Journals (Sweden)

    Gerber Heidi

    2009-12-01

    Full Text Available Abstract Background Porcine circovirus type 2 (PCV2 is a dominant causative agent of postweaning multisystemic wasting syndrome (PMWS, a multifactorial disease complex with putative immunosuppressive characteristics. Little is known about adaptive PCV2-specific immune responses in infected pigs. Therefore, the T and B cell responses following PCV2 infection in 3-week old SPF piglets infected with PCV2 or PCV2 plus porcine parvovirus (PPV were studied. Results All animals were asymptomatically infected. At 7 days post infection (d p.i., B lymphocyte and T lymphocyte numbers decreased in the dual infected, but not in the single infected piglets. At this time point a transient PCV2 viraemia was noted in the PCV2 infected groups. Antibodies against the infecting virus were detectable at day 24-28 p.i. for anti-PCV2 antibodies and at day 10 p.i. for anti-PPV antibodies, with no apparent influence of PCV2 on the early PPV antibody development. In the animals infected with PPV alone, IFN-γ secreting cells (SC that were not specific for PCV2 were detected by ELISPOT assay at day 7 p.i. Interestingly, this response was absent in the PCV2/PPV dual infected animals. PCV2-specific IFN-γ SC were observed in the PCV2/PPV infected group at 7 d p.i. and in the PCV2 single infected group at 21 d p.i. A reduction in the numbers of IFN-γ SC was observed following anti-CD4 and anti-CD8 antibody treatment, suggesting roles for both CD4+ and CD8+ T cells in the response against PCV2 infection. This was supported by an observed increase in the percentage of IFN-γ positive CD8hi cytotoxic T cells as well as IFN-γ positive CD8-/low helper T cells after PCV2 in vitro re-stimulation. Conclusions Infection of weaned SPF piglets with PCV2 alone or combined with PPV does not induce disease and in both cases a relatively slow anti-PCV2 antibody response and weak T lymphocyte responses were found. Knowledge on such immunological characteristics is important for both PCV2

  9. Analysis of dose-rate effects on cellular responses to chronic radiation exposure

    International Nuclear Information System (INIS)

    The effects in the title were studied on their expression of various genes concerned with radiation exposure by the acute (1 Gy/min) and chronic (0.007-0.694 Gy/min) irradiations to various cell lines. Cell of human origin were the primarily cultured fibroblasts (F), their immortalized strain (imF) by transduction of human teromerase transcriptase (hTERT), breast cancer MCF-7, osteosarcoma U-20S, colon cancer HCT-116 and T-cell leukemia Jurkat. Acute irradiation was done in a gamma-cell with Cs-137 gamma-ray and chronic one, in a CO2-incubator with the Cs-137 source. Expression of genes was analyzed by mRNA sequence with Genome Analyzer. Proteins of p53, p53-Ser15-P, murine double minute 2 (MDM2), p21 and a/b-tubulin were analyzed by Western blotting. D0 values of acute irradiation were found in the range of 1.1-1.4 Gy, suggesting the similar sensitivity of used cells. However, responses to chronic exposure were different from cells to cells: particularly, at 0.347 mGy/min, no effect on growth was observed in cancer-derived cells until 10 days whereas a marked growth inhibition of F and imF cells was seen after 4 days. Arrest of proliferation of F cells after 10 days exposure at 0.347 mGy/min was tentative, but at 0.694 mGy/min, it was irreversible dependently on the exposure time. They were arrested at G0 stage. Gene expression analyzed by mRNA sequence was shown to be changed even by the lowest rate 0.007 mGy/min: levels of protein expressed under control of cancer-suppressing p53 were markedly altered. Western blotting showed an increased expression of examined proteins except for p53, at higher dose than 0.069 mGy/min. Results indicated that the cellular response to radiation involved not only DNA damage but also the process of yielding the damage. (T.T.)

  10. Diminazene aceturate (Berenil modulates the host cellular and inflammatory responses to Trypanosoma congolense infection.

    Directory of Open Access Journals (Sweden)

    Shiby Kuriakose

    Full Text Available BACKGROUND: Trypanosoma congolense are extracellular and intravascular blood parasites that cause debilitating acute or chronic disease in cattle and other domestic animals. Diminazene aceturate (Berenil has been widely used as a chemotherapeutic agent for trypanosomiasis in livestock since 1955. As in livestock, treatment of infected highly susceptible BALB/c mice with Berenil leads to rapid control of parasitemia and survival from an otherwise lethal infection. The molecular and biochemical mechanisms of action of Berenil are still not very well defined and its effect on the host immune system has remained relatively unstudied. Here, we investigated whether Berenil has, in addition to its trypanolytic effect, a modulatory effect on the host immune response to Trypanosoma congolense. METHODOLOGY/PRINCIPAL FINDINGS: BALB/c and C57BL/6 mice were infected intraperitoneally with T. congolense, treated with Berenil and the expression of CD25 and FoxP3 on splenic cells was assessed directly ex vivo. In addition, serum levels and spontaneous and LPS-induced production of pro-inflammatory cytokines by splenic and hepatic CD11b⁺ cells were determined by ELISA. Berenil treatment significantly reduced the percentages of CD25⁺ cells, a concomitant reduction in the percentage of regulatory (CD4⁺Foxp3⁺ T cells and a striking reduction in serum levels of disease exacerbating pro-inflammatory cytokines including IL-6, IL-12, TNF and IFN-γ. Furthermore, Berenil treatment significantly suppressed spontaneous and LPS-induced production of inflammatory cytokines by splenic and liver macrophages and significantly ameliorated LPS-induced septic shock and the associated cytokine storm. CONCLUSIONS/SIGNIFICANCE: Collectively, these results provide evidence that in addition to its direct trypanolytic effect, Berenil also modulates the host immune response to the parasite in a manner that dampen excessive immune activation and production of pathology

  11. Advanced Computational Approaches for Characterizing Stochastic Cellular Responses to Low Dose, Low Dose Rate Exposures

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Bobby, R., Ph.D.

    2003-06-27

    OAK - B135 This project final report summarizes modeling research conducted in the U.S. Department of Energy (DOE), Low Dose Radiation Research Program at the Lovelace Respiratory Research Institute from October 1998 through June 2003. The modeling research described involves critically evaluating the validity of the linear nonthreshold (LNT) risk model as it relates to stochastic effects induced in cells by low doses of ionizing radiation and genotoxic chemicals. The LNT model plays a central role in low-dose risk assessment for humans. With the LNT model, any radiation (or genotoxic chemical) exposure is assumed to increase one¡¯s risk of cancer. Based on the LNT model, others have predicted tens of thousands of cancer deaths related to environmental exposure to radioactive material from nuclear accidents (e.g., Chernobyl) and fallout from nuclear weapons testing. Our research has focused on developing biologically based models that explain the shape of dose-response curves for low-dose radiation and genotoxic chemical-induced stochastic effects in cells. Understanding the shape of the dose-response curve for radiation and genotoxic chemical-induced stochastic effects in cells helps to better understand the shape of the dose-response curve for cancer induction in humans. We have used a modeling approach that facilitated model revisions over time, allowing for timely incorporation of new knowledge gained related to the biological basis for low-dose-induced stochastic effects in cells. Both deleterious (e.g., genomic instability, mutations, and neoplastic transformation) and protective (e.g., DNA repair and apoptosis) effects have been included in our modeling. Our most advanced model, NEOTRANS2, involves differing levels of genomic instability. Persistent genomic instability is presumed to be associated with nonspecific, nonlethal mutations and to increase both the risk for neoplastic transformation and for cancer occurrence. Our research results, based on

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

    International Nuclear Information System (INIS)

    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.

  13. Phorbol ester promotes a sustained down-regulation of endothelin receptors and cellular responses to endothelin in human vascular smooth muscle cells.

    Science.gov (United States)

    Resink, T J; Scott-Burden, T; Weber, E; Bühler, F R

    1990-02-14

    The effect of phorbol ester pretreatment of human vascular smooth muscle cells (hVSMC) was studied with respect to regulation of endothelin (ET)-receptor binding and cellular responses to ET. The capacity of hVSMC to bind ET was decreased (by approximately 50% at maximum) after phorbol exposure, and this reductive effect was both rapid (t 1/2 approximately 10 min.) and sustained (for up to 24 hrs. of chronic phorbol exposure). Phorbol pretreatment inhibited both inositol phosphate and diacylclycerol production responses of hVSMC to ET in a manner that was time-dependent and sustained. Phorbol pretreatment also produced a persistent reduction in the ability of ET to release isotopically-labelled arachidonic and/or its metabolites from hVSMC, but importantly ionomycin-stimulated release was similarly negatively affected. Furthermore, ET-induced accumulation of the phospholipase A2/phospholipase B-derived inositol phospholipid metabolite, glycerophosphoinositol, was not different between control and phorbol-treated hVMSC. The mechanism whereby phorbol exerts differential, but notably sustained inhibitory effects on ET-promoted signal transduction pathways are thus complex and illustrative of the selectivity of protein kinase C in regulating cellular responses. PMID:2154974

  14. Reconstitution of the cellular response to DNA damage in vitro using damage-activated extracts from mammalian cells

    Energy Technology Data Exchange (ETDEWEB)

    Roper, Katherine; Coverley, Dawn, E-mail: dc17@york.ac.uk

    2012-03-10

    In proliferating mammalian cells, DNA damage is detected by sensors that elicit a cellular response which arrests the cell cycle and repairs the damage. As part of the DNA damage response, DNA replication is inhibited and, within seconds, histone H2AX is phosphorylated. Here we describe a cell-free system that reconstitutes the cellular response to DNA double strand breaks using damage-activated cell extracts and naieve nuclei. Using this system the effect of damage signalling on nuclei that do not contain DNA lesions can be studied, thereby uncoupling signalling and repair. Soluble extracts from G1/S phase cells that were treated with etoposide before isolation, or pre-incubated with nuclei from etoposide-treated cells during an in vitro activation reaction, restrain both initiation and elongation of DNA replication in naieve nuclei. At the same time, H2AX is phosphorylated in naieve nuclei in a manner that is dependent upon the phosphatidylinositol 3-kinase-like protein kinases. Notably, phosphorylated H2AX is not focal in naieve nuclei, but is evident throughout the nucleus suggesting that in the absence of DNA lesions the signal is not amplified such that discrete foci can be detected. This system offers a novel screening approach for inhibitors of DNA damage response kinases, which we demonstrate using the inhibitors wortmannin and LY294002. -- Highlights: Black-Right-Pointing-Pointer A cell free system that reconstitutes the response to DNA damage in the absence of DNA lesions. Black-Right-Pointing-Pointer Damage-activated extracts impose the cellular response to DNA damage on naieve nuclei. Black-Right-Pointing-Pointer PIKK-dependent response impacts positively and negatively on two separate fluorescent outputs. Black-Right-Pointing-Pointer Can be used to screen for inhibitors that impact on the response to damage but not on DNA repair. Black-Right-Pointing-Pointer LY294002 and wortmannin demonstrate the system's potential as a pathway focused screening

  15. Reconstitution of the cellular response to DNA damage in vitro using damage-activated extracts from mammalian cells

    International Nuclear Information System (INIS)

    In proliferating mammalian cells, DNA damage is detected by sensors that elicit a cellular response which arrests the cell cycle and repairs the damage. As part of the DNA damage response, DNA replication is inhibited and, within seconds, histone H2AX is phosphorylated. Here we describe a cell-free system that reconstitutes the cellular response to DNA double strand breaks using damage-activated cell extracts and naïve nuclei. Using this system the effect of damage signalling on nuclei that do not contain DNA lesions can be studied, thereby uncoupling signalling and repair. Soluble extracts from G1/S phase cells that were treated with etoposide before isolation, or pre-incubated with nuclei from etoposide-treated cells during an in vitro activation reaction, restrain both initiation and elongation of DNA replication in naïve nuclei. At the same time, H2AX is phosphorylated in naïve nuclei in a manner that is dependent upon the phosphatidylinositol 3-kinase-like protein kinases. Notably, phosphorylated H2AX is not focal in naïve nuclei, but is evident throughout the nucleus suggesting that in the absence of DNA lesions the signal is not amplified such that discrete foci can be detected. This system offers a novel screening approach for inhibitors of DNA damage response kinases, which we demonstrate using the inhibitors wortmannin and LY294002. -- Highlights: ► A cell free system that reconstitutes the response to DNA damage in the absence of DNA lesions. ► Damage-activated extracts impose the cellular response to DNA damage on naïve nuclei. ► PIKK-dependent response impacts positively and negatively on two separate fluorescent outputs. ► Can be used to screen for inhibitors that impact on the response to damage but not on DNA repair. ► LY294002 and wortmannin demonstrate the system's potential as a pathway focused screening approach.

  16. Aerosol vaccination with AERAS-402 elicits robust cellular immune responses in the lungs of rhesus macaques but fails to protect against high-dose Mycobacterium tuberculosis challenge.

    Science.gov (United States)

    Darrah, Patricia A; Bolton, Diane L; Lackner, Andrew A; Kaushal, Deepak; Aye, Pyone Pyone; Mehra, Smriti; Blanchard, James L; Didier, Peter J; Roy, Chad J; Rao, Srinivas S; Hokey, David A; Scanga, Charles A; Sizemore, Donata R; Sadoff, Jerald C; Roederer, Mario; Seder, Robert A

    2014-08-15

    Development of a vaccine against pulmonary tuberculosis may require immunization strategies that induce a high frequency of Ag-specific CD4 and CD8 T cells in the lung. The nonhuman primate model is essential for testing such approaches because it has predictive value for how vaccines elicit responses in humans. In this study, we used an aerosol vaccination strategy to administer AERAS-402, a replication-defective recombinant adenovirus (rAd) type 35 expressing Mycobacterium tuberculosis Ags Ag85A, Ag85B, and TB10.4, in bacillus Calmette-Guérin (BCG)-primed or unprimed rhesus macaques. Immunization with BCG generated low purified protein derivative-specific CD4 T cell responses in blood and bronchoalveolar lavage. In contrast, aerosolized AERAS-402 alone or following BCG induced potent and stable Ag85A/b-specific CD4 and CD8 effector T cells in bronchoalveolar lavage that largely produced IFN-γ, as well as TNF and IL-2. Such responses induced by BCG, AERAS-402, or both failed to confer overall protection following challenge with 275 CFUs M. tuberculosis Erdman, although vaccine-induced responses associated with reduced pathology were observed in some animals. Anamnestic T cell responses to Ag85A/b were not detected in blood of immunized animals after challenge. Overall, our data suggest that a high M. tuberculosis challenge dose may be a critical factor in limiting vaccine efficacy in this model. However, the ability of aerosol rAd immunization to generate potent cellular immunity in the lung suggests that using different or more immunogens, alternative rAd serotypes with enhanced immunogenicity, and a physiological challenge dose may achieve protection against M. tuberculosis. PMID:25024382

  17. 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. PMID:24491563

  18. 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

  19. Cellular fibronectin response to supervised moderate aerobic training in patients with type 2 diabetes.

    Science.gov (United States)

    Alghadir, Ahmad H; Gabr, Sami A; Al-Eisa, Einas

    2016-04-01

    [Purpose] Physical activity is one of the most pivotal targets for the prevention and management of vascular complications, especially endothelial dysfunctions. Cellular fibronectin is an endothelium-derived protein involved in subendothelial matrix assembly. Its plasma levels reflect matrix alterations and vessel wall destruction in patients with type II diabetes. This study investigated the influence of 12 weeks of supervised aerobic training on cellular fibronectin and its relationship with insulin resistance and body weight in type II diabetic subjects. [Subjects and Methods] This study included 50 men with type II diabetes who had a mean age of 48.8 ± 14.6 years and were randomly divided into two groups: an aerobic exercise group (12 weeks, three 50 minutes sessions per week) and control group. To examine changes in cellular fibronectin, glycosylated hemoglobin, insulin resistance, fasting insulin, fasting blood sugar, and lipid profile, 5 ml of blood was taken from the brachial vein of patients before and 48 hours after completion of the exercise period and after 12 hours of fasting at rest. Data analysis was performed using the SPSS-16 software with the independent and paired t-tests. [Results] A significant decrease was observed in body mass index and body fat percentage in the experimental group. Compared with the control group, the aerobic exercise group showed a significant decrease in cellular fibronectin, glycosylated hemoglobin, insulin resistance, fasting insulin, fasting blood sugar, and lipid profile after 12 weeks of aerobic exercise. The change in cellular fibronectin showed positive significant correlation with body mass index, diabetic biomarkers, and physical activity level. [Conclusion] The results showed that supervised aerobic exercise as a stimulus can change the levels of cellular fibronectin as matrix metalloproteinase protein a long with improvement of insulin sensitivity and glycosylated hemoglobin in order to prevent

  20. Nerve growth factor-induced alteration in the response of PC12 pheochromocytoma cells to epidermal growth factor

    OpenAIRE

    Huff, K; End, D; Guroff, G

    1981-01-01

    PC12 cells, which differentiate morphologically and biochemically into sympathetic neruonlike cells in response to nerve growth fact, also respond to epidermal growth factor. The response to epidermal growth factor is similar in certain respects to the response to nerve growth fact. Both peptides produce rapid increases in cellular adhesion and 2-deoxyglucose uptake and both induce ornithine decarboxylase. But nerve growth factor causes a decreased cell proliferation and a marked hypertrophy ...

  1. P53 activation, a key event of the cellular response to gamma irradiation

    International Nuclear Information System (INIS)

    The tumor suppressor gene p53 encodes a protein whose major function is to protect organisms from proliferation of potentially tumorigenic cells. In normal conditions (unstressed cells), the p53 protein is inert and maintained at low level through its association with the Mdm2 oncogene, causing its translocation from the nucleus into the cytoplasm and its degradation through ubiquitin/proteasome pathway. In response to damaged DNA or to a variety of stresses, p53 accumulates in the nucleus and is activated as a transcriptional trans-activator. Posttranslational modifications of p53 including multi-site phosphorylation and acetylation are the major mechanism of p53 regulation. After exposure to ionising radiation, p53 activation implicates ATM, ATR, Chk2 and Chk1 kinases that phosphorylate the N-terminal domain on Ser15 (ATM and/or ATR), and Ser20 (Chk2 and/or Chk1), causing the dissociation of the p53/Mdm2 complex and thereby the stabilisation of p53. The process initiated by γ-irradiation exposure involves also increased interaction of the p53 N-terminal domain with CBP/p300 and P/CAF leading to acetylation of the distant C-terminal domain at Lys 320, 373 and 382. In addition, the ATM-mediated dephosphorylation of Ser376 creates a fixation site for 14-3-3 protein. Taken together, phosphorylation, acetylation and association with co factors induce the stimulation of p53 transcriptional activity resulting in the expression of a set of genes involved, notably, in cell cycle arrest and apoptosis. This stress-induced p53 pathways lead to one of two outcomes: growth arrest or apoptosis and consequently protects the organism from the genotoxic effects of ionising radiation. (author)

  2. Loss of VHL in RCC reduces repair and alters cellular response to benzo[a]pyrene

    Directory of Open Access Journals (Sweden)

    MartenSchults

    2013-10-01

    Full Text Available Mutations of the von Hippel-Lindau (VHL tumor suppressor gene occur in the majority of sporadic renal-cell carcinomas (RCC. Loss of VHL function is associated with stabilization of hypoxia-inducible factor α (HIFα. We and others demonstrated that there is a two-way interaction between the aryl hydrocarbon receptor, which is an important mediator in the metabolic activation and detoxification of carcinogens, and the HIF1-pathway leading to an increased genetic instability when both pathways are simultaneously activated. The aim of this study was to investigate how environmental carcinogens, such as benzo[a]pyrene (BaP, which can be metabolically activated to BaP-7,8-diOH-9,10-epoxide (BPDE play a role in the etiology of renal-cell carcinomas (RCC. We exposed VHL deficient RCC4 cells, in which HIFα is stabilized regardless of oxygen tension, to 0.1µM BaP for 18 hours. The mutagenic BPDE-DNA adduct levels were increased in HIFα stabilized cells. Using qRT-PCR, we demonstrated that absence of VHL significantly induced the mRNA levels of AhR downstream target CYP1A1. Furthermore, HPLC analysis indicated that loss of VHL increased the concentration of BaP-7,8-dihydroxydiol, the pre-cursor metabolite of BPDE. Interestingly, the capacity to repair BPDE-DNA adducts in the HIFα stabilized RCC4 cells, was markedly reduced. Taken together, these data indicate that loss of VHL affects BaP-mediated genotoxic responses in renal-cell carcinoma and decreases repair capacity.

  3. Understanding the role of p53 in adaptive response to radiation-induced germline mutations

    International Nuclear Information System (INIS)

    Full text: Radiation-induced adaptive response is now a widely studied area of radiation biology. Studies have demonstrated reduced levels of radiation-induced biological damage when an 'adaptive dose' is given before a higher 'challenge dose' compared to when the challenge dose is given alone. It has been shown in some systems to be a result of inducible cellular repair systems. The adaptive response has been clearly demonstrated in many model systems, however its impact on heritable effects in the mammalian germline has never been studied. Expanded Simple Tandem Repeat (ESTR) loci have been used as markers demonstrating that induced heritable mutations in mice follow a dose-response relationship. Recent data in our laboratory show preliminary evidence of radiation-induced adaptive response suppressing germline mutations at ESTR loci in wild type mice. The frequency of heritable mutations was significantly reduced when a priming dose of 0.1 Gy was given 24 hours prior to a 1 Gy acute challenging dose. We are now conducting a follow-up study to attempt to understand the mechanism of this adaptive response. P53 is known to play a significant role in governing apoptosis, DNA repair and cancer induction. In order to determine what function p53 has in the adaptive response for heritable mutations, we have mated radiation treated Trp53+/- male mice (C57Bl) to untreated, normal females (C57Bl). Using DNA fingerprinting, we are investigating the rate of inherited radiation-induced mutations on pre- and post-meiotic radiation-treated gametocytes by examining mutation frequencies in offspring DNA. If p53 is integral in the mechanism of adaptive response, we should not see an adaptive response in radiation-induced heritable mutations in these mice. This research is significant in that it will provide insight to understanding the mechanism behind radiation-induced adaptive response in the mammalian germline

  4. Profiling human protein degradome delineates cellular responses to proteasomal inhibition and reveals a feedback mechanism in regulating proteasome homeostasis

    OpenAIRE

    Yu, Tao; Tao, Yonghui; Yang, Meiqiang; Chen, Peng; Gao, XiaoBo; Zhang, Yanbo; Zhang,Tao; Chen, Zi; Hou, Jian; Zhang, Yan; Ruan, Kangcheng; Wang, Hongyan; Hu, Ronggui

    2014-01-01

    Global change in protein turnover (protein degradome) constitutes a central part of cellular responses to intrinsic or extrinsic stimuli. However, profiling protein degradome remains technically challenging. Recently, inhibition of the proteasome, e.g., by using bortezomib (BTZ), has emerged as a major chemotherapeutic strategy for treating multiple myeloma and other human malignancies, but systematic understanding of the mechanisms for BTZ drug action and tumor drug resistance is yet to be a...

  5. 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

  6. Development of mechano-responsive polymeric scaffolds using functionalized silica nano-fillers for the control of cellular functions

    OpenAIRE

    Griffin, M.; Nayyer, L.; Butler, P. E.; R.G. Palgrave; Seifalian, A. M.; Kalaskar, D. M.

    2016-01-01

    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 s...

  7. Engineering an Integrated Cellular Interface in Three-Dimensional Hydrogel Cultures Permits Monitoring of Reciprocal Astrocyte and Neuronal Responses*

    OpenAIRE

    East, Emma; Golding, Jon P.; Phillips, James B.

    2012-01-01

    This study reports a new type of three-dimensional (3D) tissue model for studying interactions between cell types in collagen hydrogels. The aim was to create a 3D cell culture model containing separate cell populations in close proximity without the presence of a mechanical barrier, and demonstrate its relevance to modeling the axon growth-inhibitory cellular interfaces that develop in the central nervous system (CNS) in response to damage. This provides a powerful new tool to determine whic...

  8. Analysis of cellular responses of macrophages to zinc ions and zinc oxide nanoparticles: a combined targeted and proteomic approach

    OpenAIRE

    Triboulet, Sarah,; Aude-Garcia, Catherine; Armand, Lucie; Gerdil, Adèle; Diemer, Hélène; Proamer, Fabienne; Collin-Faure, Véronique; Habert, Aurélie; Strub, Jean-Marc; Hanau, Daniel; Herlin, Nathalie; Carrière, Marie; Van Dorsselaer, Alain; Rabilloud, Thierry

    2016-01-01

    Two different zinc oxide nanoparticles, as well as zinc ions, are used to study the cellular responses of the RAW 264 macrophage cell line. A proteomic screen is used to provide a wide view of the molecular effects of zinc, and the most prominent results are cross-validated by targeted studies. Furthermore, the alteration of important macrophage functions (e.g. phagocytosis) by zinc is also investigated. The intracellular dissolution/uptake of zinc is also studied to further characterize zinc...

  9. Highlighting a Need to Distinguish Cell Cycle Signatures from Cellular Responses to Chemotherapeutics in SR-FTIR Spectroscopy

    OpenAIRE

    C Hughes, M D Brown, P Dumas, N W Clarke, K R Flower and P Gardner

    2012-01-01

    Previous research has seen difficulties in establishing clear discrimination by principal component analysis (PCA) between drug-treated cells analysed by single point SR-FTIR spectroscopy, relative to multisampling cell monolayers by conventional FTIR. It is suggested that the issue arises due to signal mixing between cellular-response signatures and cell cycle phase contributions in individual cells. Consequently, chemometric distinction of cell spectra treated with multiple drugs is difficu...

  10. Cellular Immune Responses in HIV-Negative Immunodeficiency with Anti-Interferon-γ Antibodies and Opportunistic Intracellular Microorganisms

    OpenAIRE

    Wipasa, Jiraprapa; Wongkulab, Panuwat; Chawansuntati, Kriangkrai; Chaiwarit, Romanee; Supparatpinyo, Khuanchai

    2014-01-01

    Background Cell-mediated immunity plays a crucial role in resistance to intracellular infection. We previously reported antibodies against interferon-gamma (IFN-γ) in HIV− negative (HIV−) patients with acquired immunodeficiency presenting with repeated episodes of disseminated infection caused by uncommon opportunistic intracellular fungal, bacterial, and viral pathogens. This follow-up study aimed to investigate cellular immune responses in these unusual patients. Methods Twenty HIV− patient...

  11. Experimentally induced diabetes causes glial activation, glutamate toxicity and cellular damage leading to changes in motor function

    Directory of Open Access Journals (Sweden)

    Aarti eNagayach

    2014-10-01

    Full Text Available Behavioural impairments are the most empirical consequence of diabetes mellitus documented in both humans and animal models, but the underlying causes are still poorly understood. As the cerebellum plays a major role in coordination and execution of the motor functions, we investigated the possible involvement of glial activation, cellular degeneration and glutamate transportation in the cerebellum of rats, rendered diabetic by a single injection of streptozotocin (STZ; 45mg/ kg body weight; intraperitoneally. Motor function alterations were studied using Rotarod test (motor coordination and grip strength (muscle activity at 2nd, 4th, 6th, 8th, 10th and 12th week post diabetic confirmation. Scenario of glial (astroglia and microglia activation, cell death and glutamate transportation was gauged using immunohistochemistry, histological study and image analysis. Cellular degeneration was clearly demarcated in the diabetic cerebellum. Glial cells were showing sequential and marked activation following diabetes in terms of both morphology and cell number. Bergmann glial cells were hypertrophied and distorted. Active caspase-3 positive apoptotic cells were profoundly present in all three cerebellar layers. Reduced co-labelling of GLT-1 and GFAP revealed the altered glutamate transportation in cerebellum following diabetes. These results, exclusively derived from histology, immunohistochemistry and cellular quantification, provide first insight over the associative reciprocity between the glial activation, cellular degeneration and reduced glutamate transportation, which presumably lead to the behavioural alterations following STZ-induced diabetes.

  12. Development of cellular immune response of mice to infection with low doses of Trichinella spiralis, Trichinella britovi and Trichinella pseudospiralis larvae.

    Science.gov (United States)

    Dvorožňáková, Emília; Hurníková, Zuzana; Kołodziej-Sobocińska, Marta

    2011-01-01

    The murine cellular immune response to the infection with ten larvae of encapsulating (Trichinella spiralis, Trichinella britovi) and non-encapsulating species (Trichinella pseudospiralis) was studied. Both T. spiralis and T. britovi stimulated the proliferation of splenic T and B lymphocytes during the intestinal phase of infection, but T. spiralis activated the proliferative response also at the muscle phase, particularly in B cells. Non-encapsulating T. pseudospiralis stimulated the proliferation of T and B cells only on day 10 post-infection (p.i.) and later at the muscle phase. The numbers of splenic CD4 and CD8 T cells of T. spiralis infected mice were significantly increased till day 10 p.i., i.e., at the intestinal phase, and then at the late muscle phase, on day 60 p.i. T. britovi infection increased the CD4 and CD8 T cell numbers only on day 30 p.i. Decreased numbers of CD4 and CD8 T cells after T. pseudospiralis infection suggest a suppression of cellular immunity. Both encapsulating Trichinella species induced the Th2 response (cytokines interleukin-5 (IL-5) and interleukin-10) at the intestinal phase and the Th2 dominant response at the advanced muscle phase. Interferon-γ (IFN-γ) production (Th1 type) started to increase with migrating newborn larvae from day 15 p.i. till the end of the experiment. IL-5 production was suppressed during the intestinal phase of T. pseudospiralis infection. The immune response to T. pseudospiralis was directed more to the Th1 response at the muscle phase, the high IFN-γ production was found on day 10 p.i. and it peaked on days 45 and 60 p.i. PMID:20967464

  13. Mechanisms underlying cellular responses of cells from haemopoietic tissue to low

    Energy Technology Data Exchange (ETDEWEB)

    Kadhim, Munira A

    2012-08-22

    lineages will include the role of cytokines which have been shown to be in the initiation of instability. These studies also aim to uncover the possible mechanism of the initiation, perpetuation and delayed pathways of the instability response using relevant biological endpoints i.e. chromosomal instability, apoptosis induction, cytokine and gene array analysis. Integral to these studies will be an assessment of the role of genetic susceptibility in these responses, using CBA/CaH and C57BL/6J mice. The overall results suggest that low dose low LET X-irradiation induced delayed GI in both CBA/CaH and C57BL/6J haemopoeitic tissue. Using several biological approaches, some key strain and dose-specific differences have been identified in radiation-induced signalling in the initiation and perpetuation of the instability process. Furthermore, the induction of non-targeted radiation effects and genetic dependency may be linked to the use of alternative signalling pathways and mechanisms which have potential implications on evaluation of non-targeted effects in radiation risk assessment.

  14. Sucralose induces biochemical responses in Daphnia magna.

    Directory of Open Access Journals (Sweden)

    Ann-Kristin Eriksson Wiklund

    Full Text Available The intense artificial sweetener sucralose has no bioconcentration properties, and no adverse acute toxic effects have been observed in standard ecotoxicity tests, suggesting negligible environmental risk. However, significant feeding and behavioural alterations have been reported in non-standard tests using aquatic crustaceans, indicating possible sublethal effects. We hypothesized that these effects are related to alterations in acetylcholinesterase (AChE and oxidative status in the exposed animals and investigated changes in AChE and oxidative biomarkers (oxygen radical absorbing capacity, ORAC, and lipid peroxidation, TBARS in the crustacean Daphnia magna exposed to sucralose (0.0001-5 mg L(-1. The sucralose concentration was a significant positive predictor for ORAC, TBARS and AChE in the daphnids. Moreover, the AChE response was linked to both oxidative biomarkers, with positive and negative relationships for TBARS and ORAC, respectively. These joint responses support our hypothesis and suggest that exposure to sucralose may induce neurological and oxidative mechanisms with potentially important consequences for animal behaviour and physiology.

  15. 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....... Apparent 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....... postnatal day P35 in control opossums (Monodelphis domestica) and in response to complete spinal transection (T10) at P7, when axonal growth through site of injury occurs, and P28 when this is no longer possible. Cords were collected 1 or 7 days after injury, with age-matched controls and segments rostral......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...

  16. Overexpression of HDAC1 induces cellular senescence by Sp1/PP2A/pRb pathway

    Energy Technology Data Exchange (ETDEWEB)

    Chuang, Jian-Ying [Department of Pharmacology, National Cheng-Kung University, Tainan 701, Taiwan (China); Hung, Jan-Jong, E-mail: petehung@mail.ncku.edu.tw [Department of Pharmacology, National Cheng-Kung University, Tainan 701, Taiwan (China); Institute of Bioinformatics and Biosignal Transduction, National Cheng-Kung University, Tainan 701, Taiwan (China)

    2011-04-15

    Highlights: {yields} Overexpression of HDAC1 induces Sp1 deacetylation and raises Sp1/p300 complex formation to bind to PP2Ac promoter. {yields} Overexpression of HDAC1 strongly inhibits the phosphorylation of pRb through up-regulation of PP2A. {yields} Overexpressed HDAC1 restrains cell proliferaction and induces cell senescence though a novel Sp1/PP2A/pRb pathway. -- Abstract: Senescence is associated with decreased activities of DNA replication, protein synthesis, and cellular division, which can result in deterioration of cellular functions. Herein, we report that the growth and division of tumor cells were significantly repressed by overexpression of histone deacetylase (HDAC) 1 with the Tet-off induced system or transient transfection. In addition, HDAC1 overexpression led to senescence through both an accumulation of hypophosphorylated active retinoblastoma protein (pRb) and an increase in the protein level of protein phosphatase 2A catalytic subunit (PP2Ac). HDAC1 overexpression also increased the level of Sp1 deacetylation and elevated the interaction between Sp1 and p300, and subsequently that Sp1/p300 complex bound to the promoter of PP2Ac, thus leading to induction of PP2Ac expression. Similar results were obtained in the HDAC1-Tet-off stable clone. Taken together, these results indicate that HDAC1 overexpression restrained cell proliferation and induced premature senescence in cervical cancer cells through a novel Sp1/PP2A/pRb pathway.

  17. The Loss of Cellular Junctions in Epithelial Lung Cells Induced by Cigarette Smoke Is Attenuated by Corilagin

    Directory of Open Access Journals (Sweden)

    Ximena M. Muresan

    2015-01-01

    Full Text Available Cigarette smoke (CS contains over 4700 compounds, many of which can affect cellular redox balance through free radicals production or through the modulation of antioxidant enzymes. The respiratory tract is one of the organs directly exposed to CS and it is known that CS can damage the integrity of lung epithelium by affecting cell junctions and increasing epithelium permeability. In this study, we have used a human lung epithelial cell line, Calu-3, to evaluate the effect of CS on lung epithelial cell junctions levels, with special focus on the expression of two proteins involved in intercellular communication: connexins (Cx 40 and 43. CS exposure increased Cx40 gene expression but not of Cx43. CS also induced NFκB activation and the formation of 4HNE-Cxs adducts. Since corilagin, a natural polyphenol, is able to inhibit NFκB activation, we have determined whether corilagin could counteract the effect of CS on Cxs expression. Corilagin was able to diminish CS induced Cx40 gene expression, 4HNE-Cx40 adducts formation, and NFκB activation. The results of this study demonstrated that CS induced the loss of cellular junctions in lung epithelium, possibly as a consequence of Cx-4HNE adducts formation, and corilagin seems to be able to abolish these CS induced alterations.

  18. The role of glutathione in cellular response to a tertiary t-butlhydroperoxide

    International Nuclear Information System (INIS)

    Cellular nonprotein thiols (NPSH) consist of glutathione (GSH) and of other low molecular weight species. GSH's rate of depletion is partly dependent upon the cellular capacity for resynthesis. If resynthesis is blocked by L-buthionine sulfoximine (L-BSO), GSH is depleted more rapidly. Human carcinoma cells (A549) and small cell lung carcinoma (H-69) are quickly removed of their GSH by L-BSO [ Dimethylfumarate (DMF) and are very sensitive to radiation, to radical producing drugs such as misonidazole and to peroxide or hydroperoxides. The authors focused on the toxicity of cells to hydroperoxides such as t-butylhydroperoxide (T-BOOH) because similar chemicals may be either produced through drug metabolism or are by-products of radical reaction. Cellular toxicity to t-BOOH is enhanced if GSH is depleted by L-BSO + DMF. T-BOOH also caused fragmentation of cellular DNA. GSH depleted cells are much more sensitive to the radiosensitizing effects of t-BOOH. T-BOOH does not behave as a hypoxic cell radiosensitizing drug

  19. 8th international workshop on microbeam probes of cellular radiation response. Extended abstracts

    International Nuclear Information System (INIS)

    This meeting has been held regularly since 1993. In the past, these workshops have been highly successful in bringing together groups interested in developing and applying micro-irradiation techniques to the study of cell and tissue damage by ionizing radiations. Advances in microbeam technology are continuously occurring and have greatly contributed to the studies in various fields of life sciences in ways that can not be achieved using conventional broad field exposures. Microbeam irradiation can inactivate subcellular compartments and cell/tissue sub-populations, and can be used to investigate the spatial dynamics of sub-nuclear irradiation-induced DNA damage repair and non-targeted responses such as bystander effects, or as a tool in radio-microsurgery in eukaryotes including plants, silkworm, and nematode. At the last meeting held in 2006, about 30 microbeams were reported in operation or under development in the world. Now, only also in Tokyo metropolitan area, several different microbeams, using protons, heavy charged particles, synchrotron and Al-K X-rays, are available for cell-targeting irradiation. This Workshop will provide 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. (author)

  20. The effects of short hairpin RNA-mediated silencing Net1 on ionizing radiation-induced damage responses

    International Nuclear Information System (INIS)

    Objective: To study the biological roles of the neuroepithelioma transforming gene 1 (Netl) in the cellular responses to ionizing radiation (IR)-induced damage. Methods: Specific shRNA was used to deplete Netl in cells. The effects of Netl depletion on the cellular responses to ionizing radiation were investigated through the clonogenic survival assay and immunoblotting analysis of DNA damage response proteins' phosphorylation. Results: Netl-depleted cells were more sensitive to IR, with a significantly increased induction of apoptosis. In response to IR, the phosphorylation levels of ataxia-telangiectasia mutated and checkpoint kinase 2 were much higher in the Net1-depleted cells than that in the control cells. Conclusion: Net1 protects IR-treated cells from apoptosis and possibly plays an important role in IR-induced damage response and repair. (authors)

  1. 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

  2. Salvia fruticosa reduces intrinsic cellular and H2O2-induced DNA oxidation in HEK 293 cells; assessment using flow cytometry

    Directory of Open Access Journals (Sweden)

    Saleem Bani Hani

    2014-05-01

    Conclusions: The results from this study suggest that the water-soluble extract of S. fruticosa leaves protects against both H2O2-induced and intrinsic cellular DNA oxidation in human embryonic kidney 293 cells.

  3. Cellular cholesterol accumulation modulates high fat high sucrose (HFHS) diet-induced ER stress and hepatic inflammasome activation in the development of non-alcoholic steatohepatitis.

    Science.gov (United States)

    Bashiri, Amir; Nesan, Dinushan; Tavallaee, Ghazaleh; Sue-Chue-Lam, Ian; Chien, Kevin; Maguire, Graham F; Naples, Mark; Zhang, Jing; Magomedova, Lilia; Adeli, Khosrow; Cummins, Carolyn L; Ng, Dominic S

    2016-07-01

    Non-alcoholic steatohepatitis (NASH), is the form of non-alcoholic fatty liver disease posing risk to progress into serious long term complications. Human and pre-clinical models implicate cellular cholesterol dysregulation playing important role in its development. Mouse model studies suggest synergism between dietary cholesterol and fat in contributing to NASH but the mechanisms remain poorly understood. Our laboratory previously reported the primary importance of hepatic endoplasmic reticulum cholesterol (ER-Chol) in regulating hepatic ER stress by comparing the responses of wild type, Ldlr-/-xLcat+/+ and Ldlr-/-xLcat-/- mice, to a 2% high cholesterol diet (HCD). Here we further investigated the roles of ER-Chol and ER stress in HFHS diet-induced NASH using the same strains. With HFHS diet feeding, both WT and Ldlr-/-xLcat+/+ accumulate ER-Chol in association with ER stress and inflammasome activation but the Ldlr-/-xLcat-/- mice are protected. By contrast, all three strains accumulate cholesterol crystal, in correlation with ER-Chol, albeit less so in Ldlr-/-xLcat-/- mice. By comparison, HCD feeding per se (i) is sufficient to promote steatosis and activate inflammasomes, and (ii) results in dramatic accumulation of cholesterol crystal which is linked to inflammasome activation in Ldlr-/-xLcat-/- mice, independent of ER-Chol. Our data suggest that both dietary fat and cholesterol each independently promote steatosis, cholesterol crystal accumulation and inflammasome activation through distinct but complementary pathways. In vitro studies using palmitate-induced hepatic steatosis in HepG2 cells confirm the key roles by cellular cholesterol in the induction of steatosis and inflammasome activations. These novel findings provide opportunities for exploring a cellular cholesterol-focused strategy for treatment of NASH. PMID:27090939

  4. 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.

  5. Contrasting cellular stress responses of Baikalian and Palearctic amphipods upon exposure to humic substances: environmental implications.

    Science.gov (United States)

    Protopopova, Marina V; Pavlichenko, Vasiliy V; Menzel, Ralph; Putschew, Anke; Luckenbach, Till; Steinberg, Christian E W

    2014-12-01

    The species-rich, endemic amphipod fauna of Lake Baikal does not overlap with the common Palearctic fauna; however, the underlying mechanisms for this are poorly understood. Considering that Palearctic lakes have a higher relative input of natural organic compounds with a dominance of humic substances (HSs) than Lake Baikal, we addressed the question whether HSs are candidate factors that affect the different species compositions in these water bodies. We hypothesized that interspecies differences in stress defense might reveal that Baikalian amphipods are inferior to Palearctic amphipods in dealing with HS-mediated stress. In this study, two key mechanisms of general stress response were examined: heat-shock protein 70 (HSP70) and multixenobiotic resistance-associated transporters (ABCB1). The results of quantitative polymerase chain reaction (qPCR) showed that the basal levels (in 3-day acclimated animals) of hsp70 and abcb1 transcripts were lower in Baikalian species (Eulimnogammarus cyaneus, Eulimnogammarus verrucosus, Eulimnogammarus vittatus-the most typical littoral species) than in the Palearctic amphipod (Gammarus lacustris-the only Palearctic species distributed in the Baikalian region). In the amphipods, the stress response was induced using HSs at 10 mg L(-1) dissolved organic carbon, which was higher than in sampling sites of the studied species, but well within the range (3-10 mg L(-1)) in the surrounding water bodies populated by G. lacustris. The results of qPCR and western blotting (n = 5) showed that HS exposure led to increased hsp70/abcb1 transcripts and HSP70 protein levels in G. lacustris, whereas these transcript levels remained constant or decr