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Sample records for benzoapyrene induces intercellular

  1. Estimating intercellular surface tension by laser-induced cell fusion

    International Nuclear Information System (INIS)

    Intercellular surface tension is a key variable in understanding cellular mechanics. However, conventional methods are not well suited for measuring the absolute magnitude of intercellular surface tension because these methods require determination of the effective viscosity of the whole cell, a quantity that is difficult to measure. In this study, we present a novel method for estimating the intercellular surface tension at single-cell resolution. This method exploits the cytoplasmic flow that accompanies laser-induced cell fusion when the pressure difference between cells is large. Because the cytoplasmic viscosity can be measured using well-established technology, this method can be used to estimate the absolute magnitudes of tension. We applied this method to two-cell-stage embryos of the nematode Caenorhabditis elegans and estimated the intercellular surface tension to be in the 30–90 µN m−1 range. Our estimate was in close agreement with cell–medium surface tensions measured at single-cell resolution. (communication)

  2. Benzo(a)pyrene induced structural and functional modifications in lung cystatin.

    Science.gov (United States)

    Khan, Mohd Shahnawaz; Priyadarshini, Medha; Shah, Aaliya; Tabrez, Shams; Jagirdar, Haseeb; Alsenaidy, Abdulrahman M; Bano, Bilqees

    2013-10-01

    Cystatins are thiol proteinase inhibitors ubiquitously present in the mammalian body. They serve a protective function to regulate the activities of endogenous proteinases, which may cause uncontrolled proteolysis and damage. In the present study, the effect of benzo(a)pyrene [BaP] on lung cystatin was studied to explore the hazardous effects of environmental pollutant on structural and functional integrity of the protein. The basic binding interaction was studied by UV-absorption, FT-IR, and fluorescence spectroscopy. The enhancement of total protein fluorescence with a red shift of 5 nm suggests structural scratch of lung cystatin by benzo(a)pyrene. Further, ANS binding studies reaffirm the unfolding of the thiol protease inhibitor (GLC-I) after treating with benzo(a)pyrene. The results of FT-IR spectroscopy reflect perturbation of the secondary conformation (alpha-helix to β-sheet) in goat lung cystatin on interaction with BaP. Finally, functional inactivation of cystatin on association with BaP was checked by its papain inhibitory activity. Benzo(a)pyrene (10 μM) caused complete inactivation of goat lung cystatin. Benzo(a)pyrene-induced loss of structure and function in the thiol protease inhibitor could provide a caution for lung injury caused by the pollutants and smokers.

  3. Intercellular communications in experimental radio-pathology: the radio-induced inflammatory syndrome

    International Nuclear Information System (INIS)

    The monolithic image of radiation pathology, the physiopathological mechanisms of which are limited to the conventional concept of specific ' target cell ' with mitotic and apoptotic cell death, is changing owing to our increasing knowledge about intercellular communications. The cellular radiation biology is currently enriched by the ' humoral ' radiation biology with its concept of ' target network ' including cells and intercellular messengers. The radiation-induced disorders observed in these networks take shape in the inflammatory reaction, which is largely involved, in the physiopathological development of the acute radiation syndrome. The concepts of a perpetual cascade of cytokines, leading to radiation-induced late effects with no biological latent period, are especially illustrated by the radiation-induced pneumonitis and pulmonary fibrosis. (authors)

  4. Protective effects of baicalein and wogonin against benzo[a]pyrene- and aflatoxin B(1)-induced genotoxicities.

    Science.gov (United States)

    Ueng, Y F; Shyu, C C; Liu, T Y; Oda, Y; Lin, Y L; Liao, J F; Chen, C F

    2001-12-15

    To evaluate the protective effects of baicalein and wogonin against benzo[a]pyrene- and aflatoxin (AF) B(1)-induced toxicities, the effects of these flavonoids on the genotoxicities and oxidation of benzo[a]pyrene and AFB(1) were studied in C57BL/6J mice. Baicalein and wogonin reduced benzo[a]pyrene and AFB(1) genotoxicities as monitored by the umuC gene expression response in Salmonella typhimurium TA1535/pSK1002. Baicalein added in vitro decreased liver microsomal benzo[a]pyrene hydroxylation (AHH) activity with an ic(50) of 33.9 +/- 1.4 microM at 100 microM benzo[a]pyrene. Baicalein also inhibited AFQ(1) and AFB(1)-epoxide formation from AFB(1) (50 microM) oxidation (AFO) with ic(50) values of 22.8 +/- 1.4 and 5.3 +/- 0.8 microM, respectively. However, the in vitro inhibitory effects of wogonin on AHH and AFO activities in liver microsomes were less than those of baicalein as inhibition by 500 microM wogonin was only about 51-65%. Treatment of mice with liquid diets containing 5 mM baicalein and wogonin resulted in 22 and 49% decreases in hepatic AHH activities, respectively. Baicalein treatment resulted in 39 and 32% decreases in AFQ(1) and AFB(1)-epoxide formation from liver microsomal AFO, respectively. Wogonin treatment resulted in 39 and 47% decreases in AFQ(1) and AFB(1)-epoxide formation, respectively. A 1-week pretreatment with wogonin significantly decreased hepatic DNA adduct formation in mice treated with 200 mg/kg of benzo[a]pyrene via gastrogavage. These in vitro and in vivo effects suggested that baicalein and wogonin might have beneficial effects against benzo[a]pyrene- and AFB(1)-induced hepatic toxicities and that wogonin had a stronger protective effect in vivo. PMID:11755119

  5. Salt-inducible kinase 1 regulates E-cadherin expression and intercellular junction stability

    OpenAIRE

    Eneling, Kristina; Brion, Laura; Pinto, Vanda; Pinho, Maria J.; Sznajder, Jacob I.; Mochizuki , Naoki; Emoto, Kazuo; Soares-da-Silva, Patricio; Bertorello, Alejandro M.

    2012-01-01

    The protein kinase liver kinase B1 (LKB1) regulates cell polarity and intercellular junction stability. Also, LKB1 controls the activity of salt-inducible kinase 1 (SIK1). The role and relevance of SIK1 and its downstream effectors in linking the LKB1 signals within these processes are partially understood. We hypothesize that SIK1 may link LKB1 signals to the maintenance of epithelial junction stability by regulating E-cadherin expression. Results from our studies using a mouse lung alveolar...

  6. Methoxychlor and Vinclozolin Induce Rapid Changes in Intercellular and Intracellular Signaling in Liver Progenitor Cells.

    Science.gov (United States)

    Babica, Pavel; Zurabian, Rimma; Kumar, Esha R; Chopra, Rajus; Mianecki, Maxwell J; Park, Joon-Suk; Jaša, Libor; Trosko, James E; Upham, Brad L

    2016-09-01

    Methoxychlor (MXC) and vinclozolin (VIN) are well-recognized endocrine disrupting chemicals known to alter epigenetic regulations and transgenerational inheritance; however, non-endocrine disruption endpoints are also important. Thus, we determined the effects of MXC and VIN on the dysregulation of gap junctional intercellular communication (GJIC) and activation of mitogen-activated protein kinases (MAPKs) in WB-F344 rat liver epithelial cells. Both chemicals induced a rapid dysregulation of GJIC at non-cytotoxic doses, with 30 min EC50 values for GJIC inhibition being 10 µM for MXC and 126 µM for VIN. MXC inhibited GJIC for at least 24 h, while VIN effects were transient and GJIC recovered after 4 h. VIN induced rapid hyperphosphorylation and internalization of gap junction protein connexin43, and both chemicals also activated MAPK ERK1/2 and p38. Effects on GJIC were not prevented by MEK1/2 inhibitor, but by an inhibitor of phosphatidylcholine-specific phospholipase C (PC-PLC), resveratrol, and in the case of VIN, also, by a p38 inhibitor. Estrogen (ER) and androgen receptor (AR) modulators (estradiol, ICI 182,780, HPTE, testosterone, flutamide, VIN M2) did not attenuate MXC or VIN effects on GJIC. Our data also indicate that the effects were elicited by the parental compounds of MXC and VIN. Our study provides new evidence that MXC and VIN dysregulate GJIC via mechanisms involving rapid activation of PC-PLC occurring independently of ER- or AR-dependent genomic signaling. Such alterations of rapid intercellular and intracellular signaling events involved in regulations of gene expression, tissue development, function and homeostasis, could also contribute to transgenerational epigenetic effects of endocrine disruptors. PMID:27413106

  7. Intercellular Adhension Molecule-1 in the Pathogenesis of Heroin-induced Acute Lung Injury in Rats

    Institute of Scientific and Technical Information of China (English)

    周琼; 白明; 邹世清

    2004-01-01

    The expression of intercellular adhesion molecule-1 (ICAM-1) in the pathogenesis of heroin-induced acute lung injury (ALI) in rats was investigated. The model of ALI was established by intravenous injection of heroin into tail vein in rats. Thirty-six rats were randomly divided into heroin-treated groups (1 h, 2 h, 4 h, 6 h and 24 h) and normal control group. Changes in histopathologic morphology and biological markers of ALI were measured. The expression of ICAM-1in lung tissue was detected by using immunohistochemistry and RT-PCR. The results showed that the W/D ratio and protein contents in BALF of the heroin-treated groups were significantly higher than that of the control group (P<0.01). The histopathological changes in the lung tissue were more obvious in heroin-treated groups. The ICAM-1 protein and mRNA expression in the lung tissue of heroin-treated groups were significantly increased as compared with that of the control group (P<0.01), and correlated with the ALI parameters in a time-dependent manner. Increasing of ICAM-1 expression was involved in the formation of heroin-induced lung injury. Furthermore, the level of expression was positively correlated with the severity of lung injury.

  8. Intercellular heterogeneity of radiation-induced DNS damage in the Comet assay

    International Nuclear Information System (INIS)

    The Comet assay is a method for quantifying DNA damage at the level of the individual cell where the DNA damage inflicted on a cell population can be depicted in terms of a scattered frequency distribution. In this study experimental models were used to determine whether this measurable heterogeneity of damage is variable and to identify the causes of the heterogeneity of the initial DNA damage that is immediately manifest after irradiation. The influence of intercellular differences in extent of damage and the influence of the intercellular differences in damage complexity as well as the measurability of damage were evaluated

  9. Protective effect of curcumin and chlorophyllin against DNA mutation induced by cyclophosphamide or benzo[a]pyrene

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, M.A.; Elbehairy, A.M.; Ghoneim, M.A.; Amer, H.A. [Cairo Univ., Giza (Egypt). Biochemistry Dept. and Biotechnology Center

    2007-03-15

    The current study was carried out to evaluate the potency of curcumin and chlorophyllin as natural antioxidants to reduce the oxidative stress markers induced by cyclophosphamide (CP) and benzo[a]pyrene [B(a)P] which were used as free radical inducers. For this purpose, 126 male albino rats were used. The animals were assigned into 4 main groups: negative control group; oxidant-treated group (subdivided into two subgroups: cyclophosphamide- treated group and benzo[a]pyrene-treated group); curcumin-treated group; and chlorophyllin-treated group. Liver samples were collected after two days post the oxidant inoculation and at the end of the experimental period (10 weeks). These samples were examined for determination of liver microsomal malondialdehyde (MDA), DNA fragmentation, restriction fragment length polymorphism (RFLP) and 8-hydroxy deoxyguanosine (8-OHdG) concentration. Both CP and B(a)P caused increments in DNA fragmentation percentages, liver microsomal MDA, concentration of 8-OHdG and induced point mutation. Treatment of rats with either curcumin or chlorophyllin revealed lower DNA fragmentation percentages, liver microsomal MDA concentration, concentration of 8-OHdG and prevented induction of mutations, i. e., reversed the oxidative stress induced by CP and B(a)P and proved that they were capable of protecting rats against the oxidative damage evoked by these oxidants. (orig.)

  10. Punicalagin and Ellagic Acid Demonstrate Antimutagenic Activity and Inhibition of Benzo[a]pyrene Induced DNA Adducts

    Directory of Open Access Journals (Sweden)

    Maryam Zahin

    2014-01-01

    Full Text Available Punicalagin (PC is an ellagitannin found in the fruit peel of Punica granatum. We have demonstrated antioxidant and antigenotoxic properties of Punica granatum and showed that PC and ellagic acid (EA are its major constituents. In this study, we demonstrate the antimutagenic potential, inhibition of BP-induced DNA damage, and antiproliferative activity of PC and EA. Incubation of BP with rat liver microsomes, appropriate cofactors, and DNA in the presence of vehicle or PC and EA showed significant inhibition of the resultant DNA adducts, with essentially complete inhibition (97% at 40 μM by PC and 77% inhibition by EA. Antimutagenicity was tested by Ames test. PC and EA dose-dependently and markedly antagonized the effect of tested mutagens, sodium azide, methyl methanesulfonate, benzo[a]pyrene, and 2-aminoflourine, with maximum inhibition of mutagenicity up to 90 percent. Almost all the doses tested (50–500 μM exhibited significant antimutagenicity. A profound antiproliferative effect on human lung cancer cells was also shown with PC and EA. Together, our data show that PC and EA are pomegranate bioactives responsible for inhibition of BP-induced DNA adducts and strong antimutagenic, antiproliferative activities. However, these compounds are to be evaluated in suitable animal model to assess their therapeutic efficacy against cancer.

  11. Modulatory effects of catechin hydrate against genotoxicity, oxidative stress, inflammation and apoptosis induced by benzo(a)pyrene in mice.

    Science.gov (United States)

    Shahid, Ayaz; Ali, Rashid; Ali, Nemat; Hasan, Syed Kazim; Bernwal, Preeti; Afzal, Shekh Mohammad; Vafa, Abul; Sultana, Sarwat

    2016-06-01

    Benzo(a)pyrene [B(a)P], a polycyclic aromatic hydrocarbon (PAH) is a strong mutagen and potent carcinogen. The aim of the present study was to investigate the efficacy of catechin hydrate against B(a)P induced genotoxicity, oxidative stress, inflammation, apoptosis and to explore its underlying molecular mechanisms in the lungs of Swiss albino mice. Administration of B(a)P (125 mg/kg b. wt., p. o.) increased the activities of toxicity markers such as LPO, LDH and B(a)P metabolizing enzymes [NADPH-cytochrome P450 reductase (CYPOR) and microsomal epoxide hydrolase (mEH)] with subsequent decrease in the activities of tissue anti-oxidant armory (SOD, CAT, GPx, GR, GST, QR and GSH). It also caused DNA damage and activation of apoptotic and inflammatory pathway by upregulation of TNF-α, IL-6, NF-kB, COX-2, p53, bax, caspase-3 and down regulating Bcl-2. However, pre-treatment with catechin at a dose of 20 and 40 mg/kg significantly decreased LDH, LPO, B(a)P metabolizing enzymes and increased anti-oxidant armory as well as regulated apoptosis and inflammation in lungs. Histological results also supported the protective effects of catechin. The findings of the present studies suggested that catechin as an effective natural product attenuates B(a)P induced lung toxicity. PMID:27020533

  12. Metabolic and immune impairments induced by the endocrine disruptors benzo[a]pyrene and triclosan in Xenopus tropicalis.

    Science.gov (United States)

    Regnault, Christophe; Willison, John; Veyrenc, Sylvie; Airieau, Antinéa; Méresse, Patrick; Fortier, Marlène; Fournier, Michel; Brousseau, Pauline; Raveton, Muriel; Reynaud, Stéphane

    2016-07-01

    Despite numerous studies suggesting that amphibians are highly sensitive to cumulative anthropogenic stresses, the role played by endocrine disruptors (EDs) in the decline of amphibian populations remains unclear. EDs have been extensively studied in adult amphibians for their capacity to disturb reproduction by interfering with the sexual hormone axis. Here, we studied the in vivo responses of Xenopus tropicalis males exposed to environmentally relevant concentrations of each ED, benzo[a]pyrene (BaP) and triclosan (TCS) alone (10 μg L(-1)) or a mixture of the two (10 μg L(-1) each) over a 24 h exposure period by following the modulation of the transcription of key genes involved in metabolic, sexual and immunity processes and the cellular changes in liver, spleen and testis. BaP, TCS and the mixture of the two all induced a marked metabolic disorder in the liver highlighted by insulin resistance-like and non-alcoholic fatty liver disease (NAFLD)-like phenotypes together with hepatotoxicity due to the impairment of lipid metabolism. For TCS and the mixture, these metabolic disorders were concomitant with modulation of innate immunity. These results confirmed that in addition to the reproductive effects induced by EDs in amphibians, metabolic disorders and immune system disruption should also be considered. PMID:27153234

  13. Autophagy and gap junctional intercellular communication inhibition are involved in cadmium-induced apoptosis in rat liver cells

    International Nuclear Information System (INIS)

    Cadmium (Cd) is known to induce hepatotoxicity, yet the underlying mechanism of how this occurs is not fully understood. In this study, Cd-induced apoptosis was demonstrated in rat liver cells (BRL 3A) with apoptotic nuclear morphological changes and a decrease in cell index (CI) in a time- and concentration-dependent manner. The role of gap junctional intercellular communication (GJIC) and autophagy in Cd-induced apoptosis was investigated. Cd significantly induced GJIC inhibition as well as downregulation of connexin 43 (Cx43). The prototypical gap junction blocker carbenoxolone disodium (CBX) exacerbated the Cd-induced decrease in CI. Cd treatment was also found to cause autophagy, with an increase in mRNA expression of autophagy-related genes Atg-5, Atg-7, Beclin-1, and microtubule-associated protein light chain 3 (LC3) conversion from cytosolic LC3-I to membrane-bound LC3-II. The autophagic inducer rapamycin (RAP) prevented the Cd-induced CI decrease, while the autophagic inhibitor chloroquine (CQ) caused a further reduction in CI. In addition, CBX promoted Cd-induced autophagy, as well as changes in expression of Atg-5, Atg-7, Beclin-1 and LC3. CQ was found to block the Cd-induced decrease in Cx43 and GJIC inhibition, whereas RAP had opposite effect. These results demonstrate that autophagy plays a protective role during Cd-induced apoptosis in BRL 3A cells during 6 h of experiment, while autophagy exacerbates Cd-induced GJIC inhibition which has a negative effect on cellular fate. - Highlights: • GJIC and autophagy is crucial for biological processes. • Cd exposure causes GJIC inhibition and autophagy increase in BRL 3A cells. • Autophagy protects Cd induced BRL 3A cells apoptosis at an early stage. • Autophagy exacerbates Cd-induced GJIC inhibition. • GJIC plays an important role in autophagy induced cell death or survival

  14. Autophagy and gap junctional intercellular communication inhibition are involved in cadmium-induced apoptosis in rat liver cells

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Hui [College of Veterinary Medicine, Yangzhou University, and Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009 (China); Zhuo, Liling [College of Life Science, Zaozhuang University, Zaozhuang, Shandong, 277160 (China); Han, Tao; Hu, Di; Yang, Xiaokang; Wang, Yi; Yuan, Yan; Gu, Jianhong; Bian, Jianchun; Liu, Xuezhong [College of Veterinary Medicine, Yangzhou University, and Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009 (China); Liu, Zongping, E-mail: liuzongping@yzu.edu.cn [College of Veterinary Medicine, Yangzhou University, and Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009 (China)

    2015-04-17

    Cadmium (Cd) is known to induce hepatotoxicity, yet the underlying mechanism of how this occurs is not fully understood. In this study, Cd-induced apoptosis was demonstrated in rat liver cells (BRL 3A) with apoptotic nuclear morphological changes and a decrease in cell index (CI) in a time- and concentration-dependent manner. The role of gap junctional intercellular communication (GJIC) and autophagy in Cd-induced apoptosis was investigated. Cd significantly induced GJIC inhibition as well as downregulation of connexin 43 (Cx43). The prototypical gap junction blocker carbenoxolone disodium (CBX) exacerbated the Cd-induced decrease in CI. Cd treatment was also found to cause autophagy, with an increase in mRNA expression of autophagy-related genes Atg-5, Atg-7, Beclin-1, and microtubule-associated protein light chain 3 (LC3) conversion from cytosolic LC3-I to membrane-bound LC3-II. The autophagic inducer rapamycin (RAP) prevented the Cd-induced CI decrease, while the autophagic inhibitor chloroquine (CQ) caused a further reduction in CI. In addition, CBX promoted Cd-induced autophagy, as well as changes in expression of Atg-5, Atg-7, Beclin-1 and LC3. CQ was found to block the Cd-induced decrease in Cx43 and GJIC inhibition, whereas RAP had opposite effect. These results demonstrate that autophagy plays a protective role during Cd-induced apoptosis in BRL 3A cells during 6 h of experiment, while autophagy exacerbates Cd-induced GJIC inhibition which has a negative effect on cellular fate. - Highlights: • GJIC and autophagy is crucial for biological processes. • Cd exposure causes GJIC inhibition and autophagy increase in BRL 3A cells. • Autophagy protects Cd induced BRL 3A cells apoptosis at an early stage. • Autophagy exacerbates Cd-induced GJIC inhibition. • GJIC plays an important role in autophagy induced cell death or survival.

  15. Extracellular matrix scaffolding guides lumen elongation by inducing anisotropic intercellular mechanical tension.

    Science.gov (United States)

    Li, Qiushi; Zhang, Yue; Pluchon, Perrine; Robens, Jeffrey; Herr, Keira; Mercade, Myriam; Thiery, Jean-Paul; Yu, Hanry; Viasnoff, Virgile

    2016-03-01

    The de novo formation of secretory lumens plays an important role during organogenesis. It involves the establishment of a cellular apical pole and the elongation of luminal cavities. The molecular parameters controlling cell polarization have been heavily scrutinized. In particular, signalling from the extracellular matrix (ECM) proved essential to the proper localization of the apical pole by directed protein transport. However, little is known about the regulation of the shape and the directional development of lumen into tubes. We demonstrate that the spatial scaffolding of cells by ECM can control tube shapes and can direct their elongation. We developed a minimal organ approach comprising of hepatocyte doublets cultured in artificial microniches to precisely control the spatial organization of cellular adhesions in three dimensions. This approach revealed a mechanism by which the spatial repartition of integrin-based adhesion can elicit an anisotropic intercellular mechanical stress guiding the osmotically driven elongation of lumens in the direction of minimal tension. This mechanical guidance accounts for the different morphologies of lumen in various microenvironmental conditions. PMID:26878396

  16. Staphylococcus epidermidis polysaccharide intercellular adhesin induces IL-8 expression in human astrocytes via a mechanism involving TLR2.

    LENUS (Irish Health Repository)

    Stevens, Niall T

    2009-03-01

    Staphylococcus epidermidis is an opportunistic biofilm-forming pathogen associated with neurosurgical device-related meningitis. Expression of the polysaccharide intercellular adhesin (PIA) on its surface promotes S. epidermidis biofilm formation. Here we investigated the pro-inflammatory properties of PIA against primary and transformed human astrocytes. PIA induced IL-8 expression in a dose- and\\/or time-dependent manner from U373 MG cells and primary normal human astrocytes. This effect was inhibited by depletion of N-acetyl-beta-d-glucosamine polymer from the PIA preparation with Lycopersicon esculentum lectin or sodium meta-periodate. Expression of dominant-negative versions of the TLR2 and TLR4 adaptor proteins MyD88 and Mal in U373 MG cells inhibited PIA-induced IL-8 production. Blocking IL-1 had no effect. PIA failed to induce IL-8 production from HEK293 cells stably expressing TLR4. However, in U373 MG cells which express TLR2, neutralization of TLR2 impaired PIA-induced IL-8 production. In addition to IL-8, PIA also induced expression of other cytokines from U373 MG cells including IL-6 and MCP-1. These data implicate PIA as an important immunogenic component of the S. epidermidis biofilm that can regulate pro-inflammatory cytokine production from human astrocytes, in part, via TLR2.

  17. Benzo(a)pyrene Induced p53 Mediated Male Germ Cell Apoptosis: Synergistic Protective Effects of Curcumin and Resveratrol.

    Science.gov (United States)

    Banerjee, Bhaswati; Chakraborty, Supriya; Ghosh, Debidas; Raha, Sanghamitra; Sen, Parimal C; Jana, Kuladip

    2016-01-01

    Benzo(a)pyrene (B(a)P) is an environmental toxicant that induces male germ cell apoptosis. Curcumin and resveratrol are phytochemicals with cytoprotective and anti-oxidative properties. At the same time resveratrol is also a natural Aryl hydrocarbon Receptor (AhR) antagonist. Our present study in isolated testicular germ cell population from adult male Wistar rats, highlighted the synergistic protective effect of curcumin and resveratrol against B(a)P induced p53 mediated germ cell apoptosis. Curcumin-resveratrol significantly prevented B(a)P induced decrease in sperm cell count and motility, as well as increased serum testosterone level. Curcumin-resveratrol co-treatment actively protected B(a)P induced testicular germ cell apoptosis. Curcumin-resveratrol co-treatment decreased the expression of pro-apoptotic proteins like cleaved caspase 3, 8 and 9, cleaved PARP, Apaf1, FasL, tBid. Curcumin-resveratrol co-treatment decreased Bax/Bcl2 ratio, mitochondria to cytosolic translocation of cytochrome c and activated the survival protein Akt. Curcumin-resveratrol decreased the expression of p53 dependent apoptotic genes like Fas, FasL, Bax, Bcl2, and Apaf1. B(a)P induced testicular reactive oxygen species (ROS) generation and oxidative stress were significantly ameliorated with curcumin and resveratrol. Curcumin-resveratrol co-treatment prevented B(a)P induced nuclear translocation of AhR and CYP1A1 (Cytochrome P4501A1) expression. The combinatorial treatment significantly inhibited B(a)P induced ERK 1/2, p38 MAPK and JNK 1/2 activation. B(a)P treatment increased the expression of p53 and its phosphorylation (p53 ser 15). Curcumin-resveratrol co-treatment significantly decreased p53 level and its phosphorylation (p53 ser 15). The study concludes that curcumin-resveratrol synergistically modulated MAPKs and p53, prevented oxidative stress, regulated the expression of pro and anti-apoptotic proteins as well as the proteins involved in B(a)P metabolism thus protected germ

  18. Benzo(apyrene induces similar gene expression changes in testis of DNA repair proficient and deficient mice

    Directory of Open Access Journals (Sweden)

    van Steeg Harry

    2010-05-01

    Full Text Available Abstract Background Benzo [a]pyrene (B[a]P exposure induces DNA adducts at all stages of spermatogenesis and in testis, and removal of these lesions is less efficient in nucleotide excision repair deficient Xpc-/- mice than in wild type mice. In this study, we investigated by using microarray technology whether compromised DNA repair in Xpc-/- mice may lead to a transcriptional reaction of the testis to cope with increased levels of B[a]P induced DNA damage. Results Two-Way ANOVA revealed only 4 genes differentially expressed between wild type and Xpc-/- mice, and 984 genes between testes of B[a]P treated and untreated mice irrespective of the mouse genotype. However, the level in which these B[a]P regulated genes are expressed differs between Wt and Xpc-/- mice (p = 0.000000141, and were predominantly involved in the regulation of cell cycle, translation, chromatin structure and spermatogenesis, indicating a general stress response. In addition, analysis of cell cycle phase dependent gene expression revealed that expression of genes involved in G1-S and G2-M phase arrest was increased after B[a]P exposure in both genotypes. A slightly higher induction of average gene expression was observed at the G2-M checkpoint in Xpc-/- mice, but this did not reach statistical significance (P = 0.086. Other processes that were expected to have changed by exposure, like apoptosis and DNA repair, were not found to be modulated at the level of gene expression. Conclusion Gene expression in testis of untreated Xpc-/- and wild type mice were very similar, with only 4 genes differentially expressed. Exposure to benzo(apyrene affected the expression of genes that are involved in cell cycle regulation in both genotypes, indicating that the presence of unrepaired DNA damage in testis blocks cell proliferation to protect DNA integrity in both DNA repair proficient and deficient animals.

  19. 3H thymidine an indicator of benzo(a)pyrene induced lung carcinogenesis: role of quercetin and curcumin

    International Nuclear Information System (INIS)

    Full text: Lung cancer is responsible for most of the cancer related deaths and calls for new approaches to control the menace. In the present study chemopreventive efficacy of curcumin and quercetin was investigated against benzo(a)pyrene (BP) induced lung carcinogenesis. The mice were segregated into five groups which included normal control, BP treated, BP+curcumin treated, BP+quercetin treated and BP+curcumin+quercetin treated groups. The morphological and histological analyses of tumor nodules confirmed lung carcinogenesis, after 22 weeks of single i.p. injection of BP at a dose of 100 mg/Kg body weight to mice. Tumor incidence and tumor multiplicity were observed to be 88% and 1.75, respectively in the BP treated mice. A statistically significant increase in the uptake of 3H thymidine indicative of increased DNA synthesis which in turn is the marker of uncontrolled cancer cell proliferation, was observed in the lung slices of BP treated mice. Further, BP treatment resulted in marked disruption in the histoarchitecture of lungs. Nuclei were enlarged, thickening of epithelium was seen. Structure-less masses of cells were visible all over. Nuclear pleomorphism and decreased cytoplasmic contents were also observed in BP treated mice. Squamous epithelial metaplasia, severe epithelial thickening and alveolar vocuolizations in distal airways indicative of lung carcinogensis were also observed in the BP treated mice. Supplementation with curcumin alone resulted in a significant decrease in the tumor incidence as well as tumor multicity which were observed to be 77% and 1.42 respectively. Also, quercetin significantly decreased tumor incidence and tumor multiplicity to 70% and 1.28 respectively. However, upon combined supplementation with phytochemicals, an appreciable decrease in the tumor incidence and multiplicity was observed which was found to be 60% and 1.00 respectively. Further, Supplementation with curcumin alone to BP treated mice resulted in statistically

  20. Epigallocatechin-3-gallate reduces DNA damage induced by benzo[a]pyrene diol epoxide and cigarette smoke condensate in human mucosa tissue cultures.

    Science.gov (United States)

    Baumeister, Philipp; Reiter, Maximilian; Kleinsasser, Norbert; Matthias, Christoph; Harréus, Ulrich

    2009-06-01

    Although epidemiological studies indicate cancer preventive effects of diets rich in fruit and vegetables, large clinical intervention studies conducted to evaluate dietary supplementation with micronutrients, mostly vitamins, showed disappointing results in large parts. In contrast, there is encouraging epidemiologic data indicating great chemopreventive potential of a large group of phytochemicals, namely polyphenols. This study shows the DNA protective effect epigallocatechin-3-gallate, a tea catechin, and one of the best-studied substances within this group, on carcinogen-induced DNA fragmentation in upper aerodigestive tract cells. Cell cultures from fresh oropharyngeal mucosa biopsies were preincubated with epigallocatechin-3-gallate in different concentrations before DNA damage was introduced with the metabolically activated carcinogen benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide or cigarette smoke condensate. Effects on resulting DNA fragmentation were measured using the alkaline single-cell microgel electrophoresis (comet assay). Epigallocatechin-3-gallate significantly reduced benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide-induced DNA damage by up to 51% (Pculture model. PMID:19491610

  1. DNA polymerase eta participates in the mutagenic bypass of adducts induced by benzo[a]pyrene diol epoxide in mammalian cells.

    Directory of Open Access Journals (Sweden)

    Alden C Klarer

    Full Text Available Y-family DNA-polymerases have larger active sites that can accommodate bulky DNA adducts allowing them to bypass these lesions during replication. One member, polymerase eta (pol eta, is specialized for the bypass of UV-induced thymidine-thymidine dimers, correctly inserting two adenines. Loss of pol eta function is the molecular basis for xeroderma pigmentosum (XP variant where the accumulation of mutations results in a dramatic increase in UV-induced skin cancers. Less is known about the role of pol eta in the bypass of other DNA adducts. A commonly encountered DNA adduct is that caused by benzo[a]pyrene diol epoxide (BPDE, the ultimate carcinogenic metabolite of the environmental chemical benzo[a]pyrene. Here, treatment of pol eta-deficient fibroblasts from humans and mice with BPDE resulted in a significant decrease in Hprt gene mutations. These studies in mammalian cells support a number of in vitro reports that purified pol eta has error-prone activity on plasmids with site-directed BPDE adducts. Sequencing the Hprt gene from this work shows that the majority of mutations are G>T transversions. These data suggest that pol eta has error-prone activity when bypassing BPDE-adducts. Understanding the basis of environmental carcinogen-derived mutations may enable prevention strategies to reduce such mutations with the intent to reduce the number of environmentally relevant cancers.

  2. The role of intercellular communication and oxidative metabolism in the propagation of ionizing radiation-induced biological effects

    Science.gov (United States)

    Autsavapromporn, Narongchai

    Coordinated interactions of specific molecular and biochemical processes are likely involved in the cellular responses to stresses induced by different ionizing radiations with distinctive linear energy transfer (LET) properties. Here, we investigated the roles and mechanisms of gap junction intercellular communication and oxidative metabolism in modulating cell killing and repair of potentially lethal damage (PLDR) in confluent AG1522 human fibroblasts exposed to 1 GeV protons (LET˜0.2 keV/μm), 137Cs γ rays (LET˜0.9 keV/μm), 241Am α particles (LET˜122 keV/μm) or 1 GeV/u iron ions (LET˜151 keV/μm) at doses by which all cells in the exposed cultures are irradiated. As expected, α-particles and iron ions were more effective than protons and γ rays at inducing cell killing. Holding γ- or proton-irradiated cells in the confluent state for several hours after irradiation promoted increased survival and decreased chromosomal damage. However, maintaining α-particle or iron ion-irradiated cells in the confluent state for various times prior to subculture resulted in increased rather than decreased lethality, and was associated with. persistent DNA damage and increased protein oxidation and lipid peroxidation. Inhibiting gap junction communication with 18-α-glycyrrhetinic acid or by knockdown of connexin43, a constitutive protein of junctional channels in these cells, protected against the toxic effects expressed in these cells during confluent holding. Up-regulation of antioxidant defense by ectopic over-expression of glutathione peroxidase, protected against cell killing by α-particles when cells were analyzed shortly after exposure. However, it did not attenuate the decrease in survival during confluent holding. Together, these findings indicate that the damaging effect of α particles results in oxidative stress, and the toxic effects in the hours following irradiation are amplified by intercellular communication, but the communicated molecule(s) is

  3. Modulation of low-density lipoprotein-induced inhibition of intercellular communication by antioxidants and high-density lipoproteins

    NARCIS (Netherlands)

    Zwijsen, R M; de Haan, L H; Kuivenhoven, J A; Nusselder, I C

    1991-01-01

    In order to study the capacity of antioxidants and high-density lipoproteins (HDL) to modulate the effects of low-density lipoprotein (LDL) on intercellular communication, arterial smooth muscle cells and a dye transfer method were used. LDL, in contrast to HDL, inhibited the communication between a

  4. BENZO[A]PYRENE AND ITS K-REGION DIOL INDUCE DNA DAMAGE IN C3H10T1/2C18 CELLS AS MEASURED BY THE ALKALINE SINGLE CELL GEL (COMET) ASSAY

    Science.gov (United States)

    160. Benzo[a]pyrene and its K-region diol induce DNA damage in C3HlOTl/2Cl8 cells as measured by the alkaline single cell gel (Comet) assay In a continuing series of studies on the genotoxicity ofK-region dihydrodiols of polycyclic aromatic hydrocarbons, we have repo...

  5. CD50 (intercellular adhesion molecule 3) stimulation induces calcium mobilization and tyrosine phosphorylation through p59fyn and p56lck in Jurkat T cell line

    OpenAIRE

    1994-01-01

    The leukocyte differentiation antigen, CD50, has been recently identified as the intercellular adhesion molecule 3 (ICAM-3), the third counter-receptor of leukocyte function-associated antigen 1 (LFA-1). This molecule seems to be specially involved in the adhesion events of the initial phases of the immune response. To characterize the role of CD50 in leukocyte interactions, the different molecular events induced after cross-linking of CD50 on T cell-derived Jurkat cell line have been analyze...

  6. Influence of dietary fat type on benzo(a)pyrene [B(a)P] biotransformation in a B(a)P-induced mouse model of colon cancer.

    Science.gov (United States)

    Diggs, Deacqunita L; Myers, Jeremy N; Banks, Leah D; Niaz, Mohammad S; Hood, Darryl B; Roberts, L Jackson; Ramesh, Aramandla

    2013-12-01

    In the US alone, around 60,000 lives/year are lost due to colon cancer. Diet and environment have been implicated in the development of sporadic colon tumors. The objective of this study was to determine how dietary fat potentiates the development of colon tumors through altered B(a)P biotransformation, using the Adenomatous polyposis coli with Multiple intestinal neoplasia mouse model. Benzo(a)pyrene was administered to mice through tricaprylin, and unsaturated (USF; peanut oil) and saturated (SF; coconut oil) fats at doses of 50 and 100 μg/kg via oral gavage over a 60-day period. Blood, colon, and liver were collected at the end of exposure period. The expression of B(a)P biotransformation enzymes [cytochrome P450 (CYP)1A1, CYP1B1 and glutathione-S-transferase] in liver and colon were assayed at the level of protein, mRNA and activities. Plasma and tissue samples were analyzed by reverse phase high-performance liquid chromatography for B(a)P metabolites. Additionally, DNA isolated from colon and liver tissues was analyzed for B(a)P-induced DNA adducts by the (32)P-postlabeling method using a thin-layer chromatography system. Benzo(a)pyrene exposure through dietary fat altered its metabolic fate in a dose-dependent manner, with 100 μg/kg dose group registering an elevated expression of B(a)P biotransformation enzymes, and greater concentration of B(a)P metabolites, compared to the 50 μg/kg dose group (Pcolon and liver, whose concentrations also registered a dose-dependent increase. These metabolites were found to bind with DNA and form B(a)P-DNA adducts, which may have contributed to colon tumors in a subchronic exposure regimen.

  7. Black raspberry extracts inhibit benzo(a)pyrene diol-epoxide-induced activator protein 1 activation and VEGF transcription by targeting the phosphotidylinositol 3-kinase/Akt pathway.

    Science.gov (United States)

    Huang, Chuanshu; Li, Jingxia; Song, Lun; Zhang, Dongyun; Tong, Qiangsong; Ding, Min; Bowman, Linda; Aziz, Robeena; Stoner, Gary D

    2006-01-01

    Previous studies have shown that freeze-dried black raspberry extract fractions inhibit benzo(a)pyrene [B(a)P]-induced transformation of Syrian hamster embryo cells and benzo(a)pyrene diol-epoxide [B(a)PDE]-induced activator protein-1 (AP-1) activity in mouse epidermal Cl 41 cells. The phosphotidylinositol 3-kinase (PI-3K)/Akt pathway is critical for B(a)PDE-induced AP-1 activation in mouse epidermal Cl 41 cells. In the present study, we determined the potential involvement of PI-3K and its downstream kinases on the inhibition of AP-1 activation by black raspberry fractions, RO-FOO3, RO-FOO4, RO-ME, and RO-DM. In addition, we investigated the effects of these fractions on the expression of the AP-1 target genes, vascular endothelial growth factor (VEGF) and inducible nitric oxide synthase (iNOS). Pretreatment of Cl 41 cells with fractions RO-F003 and RO-ME reduced activation of AP-1 and the expression of VEGF, but not iNOS. In contrast, fractions RO-F004 and RO-DM had no effect on AP-1 activation or the expression of either VEGF or iNOS. Consistent with inhibition of AP-1 activation, the RO-ME fraction markedly inhibited activation of PI-3K, Akt, and p70 S6 kinase (p70(S6k)). In addition, overexpression of the dominant negative PI-3K mutant delta p85 reduced the induction of VEGF by B(a)PDE. It is likely that the inhibitory effects of fractions RO-FOO3 and RO-ME on B(a)PDE-induced AP-1 activation and VEGF expression are mediated by inhibition of the PI-3K/Akt pathway. In view of the important roles of AP-1 and VEGF in tumor development, one mechanism for the chemopreventive activity of black raspberries may be inhibition of the PI-3K/Akt/AP-1/VEGF pathway. PMID:16397275

  8. Black raspberry extracts inhibit benzo(a)pyrene diol-epoxide-induced activator protein 1 activation and VEGF transcription by targeting the phosphotidylinositol 3-kinase/Akt pathway.

    Science.gov (United States)

    Huang, Chuanshu; Li, Jingxia; Song, Lun; Zhang, Dongyun; Tong, Qiangsong; Ding, Min; Bowman, Linda; Aziz, Robeena; Stoner, Gary D

    2006-01-01

    Previous studies have shown that freeze-dried black raspberry extract fractions inhibit benzo(a)pyrene [B(a)P]-induced transformation of Syrian hamster embryo cells and benzo(a)pyrene diol-epoxide [B(a)PDE]-induced activator protein-1 (AP-1) activity in mouse epidermal Cl 41 cells. The phosphotidylinositol 3-kinase (PI-3K)/Akt pathway is critical for B(a)PDE-induced AP-1 activation in mouse epidermal Cl 41 cells. In the present study, we determined the potential involvement of PI-3K and its downstream kinases on the inhibition of AP-1 activation by black raspberry fractions, RO-FOO3, RO-FOO4, RO-ME, and RO-DM. In addition, we investigated the effects of these fractions on the expression of the AP-1 target genes, vascular endothelial growth factor (VEGF) and inducible nitric oxide synthase (iNOS). Pretreatment of Cl 41 cells with fractions RO-F003 and RO-ME reduced activation of AP-1 and the expression of VEGF, but not iNOS. In contrast, fractions RO-F004 and RO-DM had no effect on AP-1 activation or the expression of either VEGF or iNOS. Consistent with inhibition of AP-1 activation, the RO-ME fraction markedly inhibited activation of PI-3K, Akt, and p70 S6 kinase (p70(S6k)). In addition, overexpression of the dominant negative PI-3K mutant delta p85 reduced the induction of VEGF by B(a)PDE. It is likely that the inhibitory effects of fractions RO-FOO3 and RO-ME on B(a)PDE-induced AP-1 activation and VEGF expression are mediated by inhibition of the PI-3K/Akt pathway. In view of the important roles of AP-1 and VEGF in tumor development, one mechanism for the chemopreventive activity of black raspberries may be inhibition of the PI-3K/Akt/AP-1/VEGF pathway.

  9. Investigation on the Protective Effects of Cranberry Against the DNA Damage Induced by Benzo[a]pyrene

    Directory of Open Access Journals (Sweden)

    José A. Morales-González

    2012-04-01

    Full Text Available There are few reports that demonstrate the antigenotoxic potential of cranberries. Although the types of berry fruits consumed worldwide are many, this paper focuses on cranberries that are commonly consumed in Mexico (Vaccinium macrocarpon species. The purpose of the present study is to determine whether cranberry ethanolic extract (CEE can prevent the DNA damage produced by benzo[a]pyrene (B[a]P using an in vivo mouse peripheral blood micronucleus assay. The experimental groups were organized as follows: a negative control group (without treatment, a positive group treated with B[a]P (200 mg/kg, a group administered with 800 mg/kg of CEE, and three groups treated with B[a]P and CEE (200, 400, and 800 mg/kg respectively. The CEE and benzo[a]pyrene were administered orally for a week, on a daily basis. During this period the body weight, the feed intake, and the determination of antigenotoxic potential were quantified. At the end of this period, we continued with the same determinations for one week more (recovery period but anymore administration of the substances. The animals treated with B[a]P showed a weight increase after the first week of administration. The same phenomenon was observed in the lots combined with B[a]P and CEE (low and medium doses. The dose of 800 mg/kg of CEE showed similar values to the control group at the end of the treatment period. In the second part of the assay, when the substances were not administered, these experimental groups regained their normal weight. The dose of CEE (800 mg/kg was not genotoxic nor cytotoxic. On the contrary, the B[a]P increases the frequency of micronucleated normochromatic erythrocytes (MNNE and reduces the rate of polychromatic erythrocytes (PE at the end of the treatment period. With respect to the combined lots, a significant decrease in the MN rate was observed from the sixth to the eighth day of treatment with the two high doses applied; the highest protection (60% was obtained with

  10. The environmental carcinogen benzo[a]pyrene induces a Warburg-like metabolic reprogramming dependent on NHE1 and associated with cell survival

    Science.gov (United States)

    Hardonnière, Kévin; Saunier, Elise; Lemarié, Anthony; Fernier, Morgane; Gallais, Isabelle; Héliès-Toussaint, Cécile; Mograbi, Baharia; Antonio, Samantha; Bénit, Paule; Rustin, Pierre; Janin, Maxime; Habarou, Florence; Ottolenghi, Chris; Lavault, Marie-Thérèse; Benelli, Chantal; Sergent, Odile; Huc, Laurence; Bortoli, Sylvie; Lagadic-Gossmann, Dominique

    2016-01-01

    Cancer cells display alterations in many cellular processes. One core hallmark of cancer is the Warburg effect which is a glycolytic reprogramming that allows cells to survive and proliferate. Although the contributions of environmental contaminants to cancer development are widely accepted, the underlying mechanisms have to be clarified. Benzo[a]pyrene (B[a]P), the prototype of polycyclic aromatic hydrocarbons, exhibits genotoxic and carcinogenic effects, and it is a human carcinogen according to the International Agency for Research on Cancer. In addition to triggering apoptotic signals, B[a]P may induce survival signals, both of which are likely to be involved in cancer promotion. We previously suggested that B[a]P-induced mitochondrial dysfunctions, especially membrane hyperpolarization, might trigger cell survival signaling in rat hepatic epithelial F258 cells. Here, we further characterized these dysfunctions by focusing on energy metabolism. We found that B[a]P promoted a metabolic reprogramming. Cell respiration decreased and lactate production increased. These changes were associated with alterations in the tricarboxylic acid cycle which likely involve a dysfunction of the mitochondrial complex II. The glycolytic shift relied on activation of the Na+/H+ exchanger 1 (NHE1) and appeared to be a key feature in B[a]P-induced cell survival related to changes in cell phenotype (epithelial-to-mesenchymal transition and cell migration). PMID:27488617

  11. Stabilization of membrane bound ATPases and lipid peroxidation by carotenoids from Chlorococcum humicola in Benzo(a)pyrene induced toxicity

    Institute of Scientific and Technical Information of China (English)

    Bhagavathy S; Sumathi P

    2012-01-01

    Objective: To identify the alteration of the membrane potential and the effect of carotenoid extracts from Chlorococcum humicola (C. humicola) on membrane bound ATPases and lipid peroxidation. Methods: The total carotenoids were extracted from C. humicola. Four groups of Swiss albino mice were treated as control, Benzo(a)pyrene [B(a)P], total carotenoids, B(a)P +total carotenoids respectively for a period of 60 days. Membrane lipid peroxidation and ATPases (Total ATPases, Ca2+- ATPases, Mg2+ - ATPases, Na+K+ - ATPase) were determined in lung, liver and erythrocyte samples. Results: The activity of total ATPase was found to be significantly increased in the B(a)P treated liver and lung tissue. Erythrocyte membrane also showed higher ATPase activity which was significantly reverted on total carotenoid treatment. Conclusions:It can be concluded that the changes in membrane potential favour the functional deterioration of physiological system. The overall findings demonstrates that the animals post treated with carotenoid extract from C. humicola may maintains the alterations in membrane bound ATPase and lipid peroxidation in tissues against the carcinogenic chemical and hence aid in establishing the membrane potential action. Therefore C. humicola can be further extended to exploits its possible application for various health benefits as neutraceuticals and food additives.

  12. Cystic squamous cell carcinomas in the lungs of Syrian golden hamsters induced by coal oven flue exhaust mixed with pyrolized tar pitch in combination with benzo(a)pyrene.

    Science.gov (United States)

    Rittinghausen, S; Dungworth, D L; Dasenbrock, C; Ernst, H; Mohr, U

    1997-02-01

    Among a variety of induced pulmonary tumours, cystic squamous cell carcinomas were observed in five Syrian hamsters that inhaled a mixture of pyrolized tar pitch with coal oven flue exhaust (PCE) and additionally received intratracheal injections of benzo(a)pyrene. The histological appearance of these particular tumours is described, compared to similar tumour types in rats and the susceptibility of both species to inert particles is discussed.

  13. Enhancement of hypoxia-induced gene expression in fish liver by the aryl hydrocarbon receptor (AhR) ligand, benzo[a]pyrene (BaP).

    Science.gov (United States)

    Yu, Richard Man Kit; Ng, Patrick Kwok Shing; Tan, Tianfeng; Chu, Daniel Ling Ho; Wu, Rudolf Shiu Sun; Kong, Richard Yuen Chong

    2008-11-21

    Fish in polluted coastal habitats commonly suffer simultaneous exposure to both hypoxia and xenobiotics. Although the adaptive molecular responses to each stress have been described, little is known about the interaction between the signaling pathways mediating these responses. Previous studies in mammalian hepatoma cell lines have shown that hypoxia-inducible factor (HIF)- and/or aryl hydrocarbon receptor (AhR)-activated gene expression is suppressed following co-exposure to hypoxia and the hallmark AhR ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). However, whether similar crosstalk exists in the non-tumor liver tissues of fish and whether other non-TCDD ligands also play the same inhibitory role in this crosstalk remain unknown. Here, the in vivo hepatic mRNA expression profiles of multiple hypoxia- and AhR-responsive genes (later gene expression=mRNA expression of the gene) were examined in the orange-spotted grouper (Epinephelus coioides) upon single and combined exposures to hypoxia and benzo[a]pyrene (BaP). Combined exposure enhanced hypoxia-induced gene expression but did not significantly alter BaP-induced gene expression. Protein carbonyl content was markedly elevated in fish subjected to combined exposure, indicating accumulation of reactive oxygen species (ROS). Application of diethyldithiocarbamate (DDC) to hypoxia-treated grouper liver explants similarly exaggerated hypoxia-induced gene expression as in the combined stress tissues in vivo. These observations suggest that ROS derived from the combined hypoxia and BaP stress have a role in enhancing hypoxia-induced gene expression.

  14. CD54/intercellular adhesion molecule 1 and major histocompatibility complex II signaling induces B cells to express interleukin 2 receptors and complements help provided through CD40 ligation

    DEFF Research Database (Denmark)

    Poudrier, J; Owens, T

    1994-01-01

    We have examined signaling roles for CD54 intercellular adhesion molecule 1 and major histocompatibility complex (MHC) II as contact ligands during T help for B cell activation. We used a T helper 1 (Th1)-dependent helper system that was previously shown to be contact as well as interleukin 2 (IL-2......) dependent to demonstrate the relative roles of CD54, MHC II, and CD40 signaling in the events leading to the induction of B cell proliferation and responsiveness to IL-2. Paraformaldehyde-fixed activated Th1-induced expression of IL-2R alpha, IL-2R beta, and B7, and upregulated MHC II and CD54 on B cells...

  15. Evaluation of anti-cancer and anti-oxidative potential of Syzygium Cumini against benzo[a]pyrene (BaP) induced gastric carcinogenesis in mice.

    Science.gov (United States)

    Goyal, P K; Verma, Preeti; Sharma, Priyanka; Parmar, Jyoti; Agarwal, Annapurna

    2010-01-01

    Syzygium cummini extract (SCE) was used in the present study to explore anti-tumor promoting activity in a stomach carcinogenesis model in mice. For this purpose, Swiss albino mice were administered with 1 mg of benzo-a-pyrene (BaP) in 100?l sesame oil by oral gavage twice a week for 4 consecutive weeks. The animals were sacrificed 14 weeks after the last administration of BaP. Oral administration of the extract to pre-treated (i.e. SCE as 25mg/kg b. wt./ day before BaP application for 2 weeks), post-treated (i.e. SCE after BaP application for 8 weeks) and pre-post treated (i.e. SCE for 2 weeks before treatment of BaP followed by the concomitant treatment with SCE and BaP for 4 weeks during and 2 weeks after the last dose of BaP) groups provided a significant reduction in tumor incidence, tumor burden and cumulative number of gastric carcinomas along with a significant elevation of phase II detoxifying enzymes, and inhibition of lipid per oxidation in the stomach. Thus, the present data suggest that the Syzygium cummini extract has anti-tumor and anti-oxidative potential against chemical induced stomach carcinogenesis.

  16. Evaluation of anti-cancer and anti-oxidative potential of Syzygium Cumini against benzo[a]pyrene (BaP) induced gastric carcinogenesis in mice.

    Science.gov (United States)

    Goyal, P K; Verma, Preeti; Sharma, Priyanka; Parmar, Jyoti; Agarwal, Annapurna

    2010-01-01

    Syzygium cummini extract (SCE) was used in the present study to explore anti-tumor promoting activity in a stomach carcinogenesis model in mice. For this purpose, Swiss albino mice were administered with 1 mg of benzo-a-pyrene (BaP) in 100?l sesame oil by oral gavage twice a week for 4 consecutive weeks. The animals were sacrificed 14 weeks after the last administration of BaP. Oral administration of the extract to pre-treated (i.e. SCE as 25mg/kg b. wt./ day before BaP application for 2 weeks), post-treated (i.e. SCE after BaP application for 8 weeks) and pre-post treated (i.e. SCE for 2 weeks before treatment of BaP followed by the concomitant treatment with SCE and BaP for 4 weeks during and 2 weeks after the last dose of BaP) groups provided a significant reduction in tumor incidence, tumor burden and cumulative number of gastric carcinomas along with a significant elevation of phase II detoxifying enzymes, and inhibition of lipid per oxidation in the stomach. Thus, the present data suggest that the Syzygium cummini extract has anti-tumor and anti-oxidative potential against chemical induced stomach carcinogenesis. PMID:21039048

  17. Assessment of Industry-Induced Urban Human Health Risks Related to Benzo[a]pyrene based on a Multimedia Fugacity Model: Case Study of Nanjing, China

    Directory of Open Access Journals (Sweden)

    Linyu Xu

    2015-05-01

    Full Text Available Large amounts of organic pollutants emitted from industries have accumulated and caused serious human health risks, especially in urban areas with rapid industrialization. This paper focused on the carcinogen benzo[a]pyrene (BaP from industrial effluent and gaseous emissions, and established a multi-pathway exposure model based on a Level IV multimedia fugacity model to analyze the human health risks in a city that has undergone rapid industrialization. In this study, GIS tools combined with land-use data was introduced to analyze smaller spatial scales so as to enhance the spatial resolution of the results. An uncertainty analysis using a Monte Carlo simulation was also conducted to illustrate the rationale of the probabilistic assessment mode rather than deterministic assessment. Finally, the results of the case study in Nanjing, China indicated the annual average human cancer risk induced by local industrial emissions during 2002–2008 (lowest at 1.99´10–6 in 2008 and highest at 3.34´10–6 in 2004, which was lower than the USEPA prescriptive level (1´10–6–1´10–4 but cannot be neglected in the long term. The study results could not only instruct the BaP health risk management but also help future health risk prediction and control.

  18. Chronic Administration of Benzo(a)pyrene Induces Memory Impairment and Anxiety-Like Behavior and Increases of NR2B DNA Methylation

    Science.gov (United States)

    Zhang, Wenping; Tian, Fengjie; Zheng, Jinping; Li, Senlin; Qiang, Mei

    2016-01-01

    Background Recently, an increasing number of human and animal studies have reported that exposure to benzo(a)pyrene (BaP) induces neurological abnormalities and is also associated with adverse effects, such as tumor formation, immunosuppression, teratogenicity, and hormonal disorders. However, the exact mechanisms underlying BaP-induced impairment of neurological function remain unclear. The aim of this study was to examine the regulating mechanisms underlying the impact of chronic BaP exposure on neurobehavioral performance. Methods C57BL mice received either BaP in different doses (1.0, 2.5, 6.25 mg/kg) or olive oil twice a week for 90 days. Memory and emotional behaviors were evaluated using Y-maze and open-field tests, respectively. Furthermore, levels of mRNA expression were measured by using qPCR, and DNA methylation of NMDA receptor 2B subunit (NR2B) was examined using bisulfate pyrosequencing in the prefrontal cortex and hippocampus. Results Compared to controls, mice that received BaP (2.5, 6.25 mg/kg) showed deficits in short-term memory and an anxiety-like behavior. These behavioral alterations were associated with a down-regulation of the NR2B gene and a concomitant increase in the level of DNA methylation in the NR2B promoter in the two brain regions. Conclusions Chronic BaP exposure induces an increase in DNA methylation in the NR2B gene promoter and down-regulates NR2B expression, which may contribute to its neurotoxic effects on behavioral performance. The results suggest that NR2B vulnerability represents a target for environmental toxicants in the brain. PMID:26901155

  19. Chronic Administration of Benzo(apyrene Induces Memory Impairment and Anxiety-Like Behavior and Increases of NR2B DNA Methylation.

    Directory of Open Access Journals (Sweden)

    Wenping Zhang

    Full Text Available Recently, an increasing number of human and animal studies have reported that exposure to benzo(apyrene (BaP induces neurological abnormalities and is also associated with adverse effects, such as tumor formation, immunosuppression, teratogenicity, and hormonal disorders. However, the exact mechanisms underlying BaP-induced impairment of neurological function remain unclear. The aim of this study was to examine the regulating mechanisms underlying the impact of chronic BaP exposure on neurobehavioral performance.C57BL mice received either BaP in different doses (1.0, 2.5, 6.25 mg/kg or olive oil twice a week for 90 days. Memory and emotional behaviors were evaluated using Y-maze and open-field tests, respectively. Furthermore, levels of mRNA expression were measured by using qPCR, and DNA methylation of NMDA receptor 2B subunit (NR2B was examined using bisulfate pyrosequencing in the prefrontal cortex and hippocampus.Compared to controls, mice that received BaP (2.5, 6.25 mg/kg showed deficits in short-term memory and an anxiety-like behavior. These behavioral alterations were associated with a down-regulation of the NR2B gene and a concomitant increase in the level of DNA methylation in the NR2B promoter in the two brain regions.Chronic BaP exposure induces an increase in DNA methylation in the NR2B gene promoter and down-regulates NR2B expression, which may contribute to its neurotoxic effects on behavioral performance. The results suggest that NR2B vulnerability represents a target for environmental toxicants in the brain.

  20. Neonatal exposure to benzo[a]pyrene induces oxidative stress causing altered hippocampal cytomorphometry and behavior during early adolescence period of male Wistar rats.

    Science.gov (United States)

    Patel, Bhupesh; Das, Saroj Kumar; Das, Swagatika; Das, Lipsa; Patri, Manorama

    2016-05-01

    Environmental neurotoxicants like benzo[a]pyrene (B[a]P) have been well documented regarding their potential to induce oxidative stress. However, neonatal exposure to B[a]P and its subsequent effect on anti-oxidant defence system and hippocampal cytomorphometry leading to behavioral changes have not been fully elucidated. We investigated the effect of acute exposure of B[a]P on five days old male Wistar pups administered with single dose of B[a]P (0.2 μg/kg BW) through intracisternal mode. Control group was administered with vehicle i.e., DMSO and a separate group of rats without any treatment was taken as naive group. Behavioral analysis showed anxiolytic-like behavior with significant increase in time spent in open arm in elevated plus maze. Further, significant reduction in fall off time during rotarod test showing B[a]P induced locomotor hyperactivity and impaired motor co-ordination in adolescent rats. B[a]P induced behavioral changes were further associated with altered anti-oxidant defence system involving significant reduction in the total ATPase, Na(+) K(+) ATPase, Mg(2+) ATPase, GR and GPx activity with a significant elevation in the activity of catalase and GST as compared to naive and control groups. Cytomorphometry of hippocampus showed that the number of neurons and glia in B[a]P treated group were significantly reduced as compared to naive and control. Subsequent observation showed that the area and perimeter of hippocampus, hippocampal neurons and neuronal nucleus were significantly reduced in B[a]P treated group as compared to naive and control. The findings of the present study suggest that the alteration in hippocampal cytomorphometry and neuronal population associated with impaired antioxidant signaling and mood in B[a]P treated group could be an outcome of neuromorphological alteration leading to pyknotic cell death or impaired differential migration of neurons during early postnatal brain development. PMID:26946409

  1. Activation of transcription factor AP-2 mediates UVA radiation- and singlet oxygen-induced expression of the human intercellular adhesion molecule 1 gene

    Energy Technology Data Exchange (ETDEWEB)

    Grether-Beck, S.; Olaizola-Horn, S.; Schmitt, H.; Grewe, M. [Clinical and Experimental Photodermatology, Duesseldorf (Germany)] [and others

    1996-12-10

    UVA radiation is the major component of the UV solar spectrum that reaches the earth, and the therapeutic application of UVA radiation is increasing in medicine. Analysis of the cellular effects of UVA radiation has revealed that exposure of human cells to UVA radiation at physiological doses leads to increased gene expression and that this UVA response is primarily mediated through the generation of singlet oxygen. In this study, the mechanisms by which UVA radiation induces transcriptional activation of the human intercellular adhesion molecule 1 (ICAM-1) were examined. UVA radiation was capable of inducing activation of the human ICAM-1 promoter and increasing OCAM-1 mRNA and protein expression. These UVA radiation effects were inhibited by singlet oxygen quenchers, augmented by enhancement of singlet oxygen life-time, and mimicked in unirradiated cells by a singlet oxygen-generating system. UVA radiation as well as singlet oxygen-induced ICAM-1 promoter activation required activation of the transcription factor AP-2. Accordingly, both stimuli activated AP-2, and deletion of the putative AP-2-binding site abrogated ICAM-1 promoter activation in this system. This study identified the AP-2 site as the UVA radiation- and singlet oxygen-responsive element of the human ICAM-1 gene. The capacity of UVA radiation and/or singlet oxygen to induce human gene expression through activation of AP-2 indicates a previously unrecognized role of this transcription factor in the mammalian stress response. 38 refs., 3 figs., 3 tabs.

  2. Modulation of benzo[a]pyrene induced neurotoxicity in female mice actively immunized with a B[a]P–diphtheria toxoid conjugate

    Energy Technology Data Exchange (ETDEWEB)

    Schellenberger, Mario T.; Grova, Nathalie; Farinelle, Sophie; Willième, Stéphanie [Institute of Immunology, Centre de Recherche Public de la Santé/Laboratoire National de Santé, 20A rue Auguste Lumière, L-1950 Luxembourg, Grand-Duchy of Luxembourg (Luxembourg); Schroeder, Henri [University of Nancy, URAFPA, INRA UC340, F-54500 Vandoeuvre-lès-Nancy (France); Muller, Claude P., E-mail: claude.muller@crp-sante.lu [Institute of Immunology, Centre de Recherche Public de la Santé/Laboratoire National de Santé, 20A rue Auguste Lumière, L-1950 Luxembourg, Grand-Duchy of Luxembourg (Luxembourg)

    2013-09-01

    Benzo[a]pyrene (B[a]P) is a small molecular weight carcinogen and the prototype of polycyclic aromatic hydrocarbons (PAHs). While these compounds are primarily known for their carcinogenicity, B[a]P and its metabolites are also neurotoxic for mammalian species. To develop a prophylactic immune strategy against detrimental effects of B[a]P, female Balb/c mice immunized with a B[a]P–diphtheria toxoid (B[a]P–DT) conjugate vaccine were sub-acutely exposed to 2 mg/kg B[a]P and behavioral performances were monitored in tests related to learning and memory, anxiety and motor coordination. mRNA expression of the NMDA receptor (NR1, 2A and 2B subunits) involved in the above behavioral functions was measured in 5 brain regions. B[a]P induced NMDA1 expression in three (hippocampus, amygdala and cerebellum) of five brain regions investigated, and modulated NMDA2 in two of the five brain regions (frontal cortex and cerebellum). Each one of these B[a]P-effects was reversed in mice that were immunized against this PAH, with measurable consequences on behavior such as anxiety, short term learning and memory. Thus active immunization against B[a]P with a B[a]P–DT conjugate vaccine had a protective effect and attenuated the pharmacological and neurotoxic effects even of high concentrations of B[a]P. - Highlights: • B[a]P-antibodies attenuated B[a]P induced NMDA expression in several brain regions. • B[a]P had measurable consequences on anxiety, short term learning and memory. • B[a]P immunization attenuated the pharmacological and neurotoxic effects of B[a]P. • Vaccination may also provide some protection against chemical carcinogenesis.

  3. Neonatal Benzo[a]pyrene Exposure Induces Oxidative Stress and DNA Damage Causing Neurobehavioural Changes during the Early Adolescence Period in Rats.

    Science.gov (United States)

    Patel, Bhupesh; Das, Saroj Kumar; Patri, Manorama

    2016-01-01

    Humans are exposed to polycyclic aromatic hydrocarbons (PAHs) by ingestion of contaminated food and water. Prenatal exposure to benzo[a]pyrene (B[a]P) like PAHs through the placental barrier and neonatal exposure by breast milk and the environment may affect early brain development. In the present study, single intracisternal administration of B[a]P (0.2 and 2.0 µg/kg body weight) to male Wistar rat pups at postnatal day 5 (PND5) was carried out to study its specific effect on neonatal brain development and its consequences at PND30. B[a]P administration showed a significant increase in exploratory and anxiolytic-like behaviour with elevated hippocampal lipid peroxidation and protein oxidation at PND30. Further, DNA damage was estimated in vitro (Neuro2a and C6 cell lines) by the comet assay, and oxidative DNA damage of hippocampal sections was measured in vivo following exposure to B[a]P. DNA strand breaks (single and double) significantly increased due to B[a]P at PND30 in hippocampal neurons and increased the nuclear tail moment in Neuro2a cells. Hippocampal 8-oxo-2'-deoxyguanosine production was significantly elevated showing expression of more TUNEL-positive cells in both doses of B[a]P. Histological studies also revealed a significant reduction in mean area and perimeter of hippocampal neurons in rats treated with B[a]P 2.0 μg/kg, when compared to naïve and control rats. B[a]P significantly increased anxiolytic-like behaviour and oxidative DNA damage in the hippocampus causing apoptosis that may lead to neurodegeneration in adolescence. The findings of the present study address the potential role of B[a]P in inducing oxidative stress-mediated neurodegeneration in the hippocampus through oxidative DNA damage in the early adolescence period of rats. PMID:27271523

  4. Chemopreventive potential of Triphala (a composite Indian drug) on Benzo(a)pyrene induced forestomach tumorigenesis in murine tumor model system

    Energy Technology Data Exchange (ETDEWEB)

    Deep, G.; Dhirman, M.; Rao, A.R.; Kale, R.K. [Jawaharlan Nehru Univ., New Delhi (India). Radiation and Cancer Biology Laboratory

    2005-12-15

    The present work is probably the first report on cancer chemopreventive potential of Triphala, a combination of fruit powder of three different plants namely Terminalia chebula, Terminalia belerica and Emblica officinalis. Triphala is a popular formulation of the Ayurvedic system of medicine. Our findings have shown that Triphala in diet has significantly reduced the benzo(a)pyrene [B(a)P] induced forestomach papillomagenesis in mice. In the short term treatment groups, the tumor incidences were lowered to 77.77% by both doses of Triphala mixed diet. In the case of long-term treatment the tumor incidences were reduced to 66.66% and 62.50% respectively by 2.5% and 5% triphala containing diet. Tumor burden was 7.27{+-}1.16 in the B(a)P treated control group, whereas it reduced to 3.00{+-}0.82 (p<0.005) by 2.5% dose and 2.33 +/- 1.03 (p<0.001) by 5% dose of Triphala. In long-term studies the tumor burden was reduced to 2.17{+-}0.75 (p<0.001) and 2.00{+-}0.71 (p<0.001) by 2.5% and 5% diet of Triphala, respectively. It was important to observe that Triphala was more effective in reducing tumor incidences compared to its individual constituents. Triphala also significantly increased the antioxidant status of animals which might have contributed to the chemoprevention. It was inferred that the concomitant use of multiple agents seemed to have a high degree of chemoprevention potential.

  5. Red paprika (Capsicum annuum L.) and its main carotenoids, capsanthin and β-carotene, prevent hydrogen peroxide-induced inhibition of gap-junction intercellular communication.

    Science.gov (United States)

    Kim, Ji-Sun; Lee, Woo-Moon; Rhee, Han Cheol; Kim, Suna

    2016-07-25

    This study was conducted to investigate the protective effect of red paprika extract (RPE) and its main carotenoids, namely, capsanthin (CST) and β-carotene (BCT), on the H2O2-induced inhibition of gap-junction intercellular communication (GJIC) in WB-F344 rat liver epithelial cells (WB cells). We found that pre-treatment with RPE, CST and BCT protected WB cells from H2O2-induced inhibition of GJIC. RPE, CST and BCT not only recovered connexin 43 (Cx43) mRNA expression but also prevented phosphorylation of Cx43 protein by H2O2 treatment. RPE attenuated the phosphorylation of ERK, p38 and JNK, whereas pre-treatment with CST and BCT only attenuated the phosphorylation of ERK and p38 and did not affect JNK in H2O2-treated WB cells. RPE, CST and BCT significantly suppressed the formation of reactive oxygen species (ROS) in H2O2-treated cells compared to untreated WB cells. These results suggest that dietary intake of red paprika might be helpful for lowering the risk of diseases caused by oxidative stress. PMID:27154496

  6. The Expression of Integrin β3 and Intercellular Adhesion Molecule(ICAM-1)in Decidua and Chorionic Villi during Mifepristone Induced Abortion

    Institute of Scientific and Technical Information of China (English)

    李瑞珍; 王振海; 吴瑞芳

    1999-01-01

    The effects of mifepristone with misoprostol on the expression of the integrin β3 and intercellular adhesion motecule-1 (ICAM-1)in decidua and chorionic villi tissues in early pregnancy in 10 cases were investigated by immuno-ftow cytometry(the eyper-iment group).At the same time,the other 10 cases induced by mechanical vacuum as-piration were collected as the control.The results showed that,the positive rate of inte-grin β3 and ICAM-1 in decidua of the experiment group were 19.1±5. 01% and 20.61±6. 51%;while those in chorionic villi were 21.32±4. 38% and 20. 29±6. 49%,which were significantly lower than those in the control group.These results suggested that integrin β3 and ICAM-1 may take part in the maintenance of early pregnancy.The mechanism of mifepristone induced abortion may be mediated by the down-regulation of the integrin β3 and ICAM-1 expression in decidua and chorionic villi.

  7. Cardiotrophin-1 induces intercellular adhesion molecule-1 expression by nuclear factor κB activation in human umbilical vein endothelial cells

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Background In addition to elevated concentrations of cytokines, patients with congestive heart failure (CHF) show endothelial dysfunction and increased plasma concentrations of adhesion molecules like intercellular adhesion molecule-1 (ICAM-1). Furthermore, the concentration of cardiotrophin-1 (CT-1) - a cytokine of the interleukin-6 superfamily - is increased in CHF. We tested the hypothesis whether CT-1 is able to induce ICAM-1 in human umbilical vein endothelial cells (HUVEC). Furthermore we examined the signalling mechanisms of CT-1 mediated ICAM-1 expression. Methods Confluent layers of HUVEC were incubated with increasing concentrations of CT-1 (5 to 100 ng/ml) for different periods. ICAM-1 mRNA was determined by real-time polymerase chain reaction (PCR) and ICAM-1 surface expression by fluorescence-activated cell sorter (FACS) analysis and soluble ICAM-1 (slCAM-1) in the culture supematant by enzyme linked immunosorbent assay (ELISA). To clarify the signalling pathway of CT-1 induced ICAM-1 expression we used various inhibitors of possible signal transducing molecules, electromobility shift assay (EMSA) and Western blot analysis. Results CT-1 induced ICAM-1 mRNA (1.8i-0.8 fold increase compared to unstimulated cells after 6 hours) and protein (1.4~-0.2 fold increase compared to unstimulated cells after 48 hours) in HUVEC in a time- and concentration-dependent manner. EMSA experiments show that CT-1 causes nuclear factor (NF) KB activation. Because parthenolide could inhibit CT-1 induced ICAM-1 expression NFKB activation is required in this pathway. CT-1 did not activate extraceUular signal regulated kinases (ERK), c-Jun N-terminal kinase (JNK) and p38. Conclusion CT-1 is able to induce ICAM-1 in endothelial cells by NFKB activation. These results may explain in part elevated ICAM-1 concentrations in patients with CHF and endothelial dysfunction.

  8. Prostaglandins and their precursors can modify genetic damage-induced by gamma-radiation and benzo(a)pyrene

    International Nuclear Information System (INIS)

    Experiments were performed to study the effect of various prostaglandins (PGs) and their precursors, gamma-linolenic acid (GLA) and arachidonic acid (AA) on gamma-radiation and benzo (a) pyrene (BP)-induced genetic damage to the bone marrow cells of mice, using the sensitive micronucleus (MN) test. Thromboxane B2 prostaglandin E1 and GLA completely prevented BP-induced and reduced to a great degree radiation-induced genetic damage, where as PGE2, PGF2 alpha and AA were without any effect. Since GLA and AA are widely distributed in the cell membranes, and as PGs can be formed virtually in response to any type of stimulus, it is likely that GLA and PGE1 may function as endogenous anti-mutagenic chemicals

  9. Lack of contribution of covalent benzo[a]pyrene-7,8-quinone-DNA adducts in benzo[a]pyrene-induced mouse lung tumorigenesis

    Science.gov (United States)

    Benzo[a]pyrene (B[a]P) is a potent human and rodent lung carcinogen. This activity has been ascribed in part to the formation of anti-trans-B[a]P-7,8-diol-9,10-epoxide (BPDE)-DNA adducts. Other carcinogenic mechanisms have been proposed: 1.] The induction of apurinic sites from r...

  10. 14C glucose uptake and turnover, a biomarker in benzo(a)pyrene induced lung carcinogenesis: role of curcumin and resveratrol

    International Nuclear Information System (INIS)

    Full text: The aim of the present study was to explore the synergistic potential of curcumin and resveratrol in modulation of glucose metabolism by studying 14C glucose uptake, turnover in the lung slices and ultra-histoarchitectural changes during benzo(a)pyrene (BP) induced lung carcinogenesis in mice. The mice were segregated into five treatment groups which included group I (normal control), group II (BP treated), group III (BP+curcumin treated), group IV (BP+resveratrol treated) and group V (BP+curcumin+resveratrol treated). Animals in Group II were given a single intraperitoneal injection of Benzo(a)pyrene in corn oil at a dose level of 100mg/Kg body weight. Group III animals were given curcumin orally in drinking water at a dose level of 60 mg /Kg/ body weight, thrice a week. Animals in Group IV were given resveratrol orally at a dose level of 5.7 microgram/ml drinking water, thrice a week. Animals in group V were given a combined treatment of curcumin and resveratrol in a similar manner as was given to group III and group IV animals, respectively. All the animals had free access to the diet and water and the treatments continued for a total duration of 22 weeks. The morphological and ultra-histoachitectural analyses confirmed lung carcinogenesis, in the BP treated mice. Tumor incidence and tumor multiplicity were observed to be 88% and 1.75 respectively in the BP treated mice. A statistically significant increase in the uptake of 14C glucose was observed in the lung slices of BP treated mice. Further, radiorespirometric analyses of 14C turnover also showed a significant increase in the lung slices of BP treated mice. The ultra-histoarchitecture of the BP treated mice revealed disruption in cellular integrity along with nuclear deformation. Mitochondria were swollen and cytoplasm appeared granular along with extensive vacuolization. Further, spaces between the endothelium, epithelium and basement membrane indicative of lung injury and edema were observed in

  11. Vitamin C Attenuates Hemorrhagic Shock-induced Dendritic Cell-specific Intercellular Adhesion Molecule 3-grabbing Nonintegrin Expression in Tubular Epithelial Cells and Renal Injury in Rats

    Institute of Scientific and Technical Information of China (English)

    Li Ma; Jian Fei; Ying Chen; Bing Zhao; Zhi-Tao Yang; Lu Wang; Hui-Qiu Sheng

    2016-01-01

    Background:The expression of dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) in renal tubular epithelial cells has been thought to be highly correlated with the occurrence of several kidney diseases,but whether it takes place in renal tissues during hemorrhagic shock (HS) is unknown.The present study aimed to investigate this phenomenon and the inhibitory effect of Vitamin C (VitC).Methods:A Sprague-Dawley rat HS model was established in vivo in this study.The expression level and location of DC-SIGN were observed in kidneys.Also,the degree of histological damage,the concentrations of tumor necrosis factor-α and interleukin-6 in the renal tissues,and the serum concentration of blood urea nitrogen and creatinine at different times (2-24 h) after HS (six rats in each group),with or without VitC treatment before resuscitation,were evaluated.Results:HS induced DC-SIGN expression in rat tubular epithelial cells.The proinflammatory cytokine concentration,histological damage scores,and functional injury of kidneys had increased.All these phenomena induced by HS were relieved when the rats were treated with VitC before resuscitation.Conclusions:The results of the present study illustrated that HS could induce tubular epithelial cells expressing DC-SIGN,and the levels of proinflammatory cytokines in the kidney tissues improved correspondingly.The results also indicated that VitC could suppress the DC-SIGN expression in the tubular epithelial cells induced by HS and alleviate the inflammation and functional injury in the kidney.

  12. Circulating intercellular adhesion molecule-1 (ICAM-1) as an early and sensitive marker for virus-induced T cell activation

    DEFF Research Database (Denmark)

    Christensen, Jan Pravsgaard; Johansen, J; Marker, O;

    1995-01-01

    The effect of systemic virus infection on the level of circulating ICAM-1 (cICAM-1) in serum, and the role of virus-activated T cells in this context, were studied using the murine lymphocytic choriomeningitis virus infection as primary model system. A marked virus-induced elevation in cICAM-1...... in serum was revealed, the presence of which coincided with the phase of virus-induced T cell activation. However, high levels of cICAM-1 in serum were observed well before maximal T cell activation could be demonstrated. No increase in cICAM-1 was observed in the serum of infected T cell-deficient nude...... induce shedding of ICAM-1 into the circulation, and this parameter may be used as an early and sensitive marker for immune activation....

  13. Singlet oxygen treatment of tumor cells triggers extracellular singlet oxygen generation, catalase inactivation and reactivation of intercellular apoptosis-inducing signaling.

    Science.gov (United States)

    Riethmüller, Michaela; Burger, Nils; Bauer, Georg

    2015-12-01

    Intracellular singlet oxygen generation in photofrin-loaded cells caused cell death without discrimination between nonmalignant and malignant cells. In contrast, extracellular singlet oxygen generation caused apoptosis induction selectively in tumor cells through singlet oxygen-mediated inactivation of tumor cell protective catalase and subsequent reactivation of intercellular ROS-mediated apoptosis signaling through the HOCl and the NO/peroxynitrite signaling pathway. Singlet oxygen generation by extracellular photofrin alone was, however, not sufficient for optimal direct inactivation of catalase, but needed to trigger the generation of cell-derived extracellular singlet oxygen through the interaction between H2O2 and peroxynitrite. Thereby, formation of peroxynitrous acid, generation of hydroxyl radicals and formation of perhydroxyl radicals (HO2(.)) through hydroxyl radical/H2O2 interaction seemed to be required as intermediate steps. This amplificatory mechanism led to the formation of singlet oxygen at a sufficiently high concentration for optimal inactivation of membrane-associated catalase. At low initial concentrations of singlet oxygen, an additional amplification step needed to be activated. It depended on singlet oxygen-dependent activation of the FAS receptor and caspase-8, followed by caspase-8-mediated enhancement of NOX activity. The biochemical mechanisms described here might be considered as promising principle for the development of novel approaches in tumor therapy that specifically direct membrane-associated catalase of tumor cells and thus utilize tumor cell-specific apoptosis-inducing ROS signaling.

  14. Singlet oxygen treatment of tumor cells triggers extracellular singlet oxygen generation, catalase inactivation and reactivation of intercellular apoptosis-inducing signaling.

    Science.gov (United States)

    Riethmüller, Michaela; Burger, Nils; Bauer, Georg

    2015-12-01

    Intracellular singlet oxygen generation in photofrin-loaded cells caused cell death without discrimination between nonmalignant and malignant cells. In contrast, extracellular singlet oxygen generation caused apoptosis induction selectively in tumor cells through singlet oxygen-mediated inactivation of tumor cell protective catalase and subsequent reactivation of intercellular ROS-mediated apoptosis signaling through the HOCl and the NO/peroxynitrite signaling pathway. Singlet oxygen generation by extracellular photofrin alone was, however, not sufficient for optimal direct inactivation of catalase, but needed to trigger the generation of cell-derived extracellular singlet oxygen through the interaction between H2O2 and peroxynitrite. Thereby, formation of peroxynitrous acid, generation of hydroxyl radicals and formation of perhydroxyl radicals (HO2(.)) through hydroxyl radical/H2O2 interaction seemed to be required as intermediate steps. This amplificatory mechanism led to the formation of singlet oxygen at a sufficiently high concentration for optimal inactivation of membrane-associated catalase. At low initial concentrations of singlet oxygen, an additional amplification step needed to be activated. It depended on singlet oxygen-dependent activation of the FAS receptor and caspase-8, followed by caspase-8-mediated enhancement of NOX activity. The biochemical mechanisms described here might be considered as promising principle for the development of novel approaches in tumor therapy that specifically direct membrane-associated catalase of tumor cells and thus utilize tumor cell-specific apoptosis-inducing ROS signaling. PMID:26225731

  15. Hepcidin gene expression induced in the developmental stages of fish upon exposure to Benzo[a]pyrene (BaP).

    Science.gov (United States)

    Wang, Ke-Jian; Bo, Jun; Yang, Ming; Hong, Hua-Sheng; Wang, Xin-Hong; Chen, Fang-Yi; Yuan, Jian-Jun

    2009-04-01

    Hepcidin is known to be expressed in fish with bacterial challenge and iron overload. Here we first report the hepcidin expression induced in the developmental stages from embryo to fry of red sea bream (Pagarus major) and in juvenile black porgy (Acanthopagrus schlegelii B.) upon continuous waterborne exposure to BaP. The gene expression of CYP1A1 and IgL (immunoglobulin light chain) were both measured. Expression of the Pagarus major hepcidin gene (PM-hepc) was increased in post hatch fry at 24 h and 120 h exposure to BaP at concentrations of 0.1, 0.5 and 1.0 microg/l, respectively. The gene expression pattern was comparable to that of CYP1A1 but different from that of IgL. In addition, a high number of AS-hepc2 transcripts (Acanthopagrus schlegelii B. hepcidin gene) were detected in the liver upon exposure to 1.0 microg/l BaP. This study demonstrates that hepcidin gene expression is significantly induced in BaP-exposed red sea bream and black porgy.

  16. CKIP-1 ameliorates high glucose-induced expression of fibronectin and intercellular cell adhesion molecule-1 by activating the Nrf2/ARE pathway in glomerular mesangial cells.

    Science.gov (United States)

    Gong, Wenyan; Chen, Cheng; Xiong, Fengxiao; Yang, Zhiying; Wang, Yu; Huang, Junying; Liu, Peiqing; Huang, Heqing

    2016-09-15

    Glucose and lipid metabolism disorders as well as oxidative stress (OSS) play important roles in diabetic nephropathy (DN). Glucose and lipid metabolic dysfunctions are the basic pathological changes of chronic microvascular complications of diabetes mellitus, such as DN. OSS can lead to the accumulation of extracellular matrix and inflammatory factors which will accelerate the progress of DN. Casein kinase 2 interacting protein-1 (CKIP-1) mediates adipogenesis, cell proliferation and inflammation under many circumstances. However, whether CKIP-1 is involved in the development of DN remains unknown. Here, we show that CKIP-1 is a novel regulator of resisting the development of DN and the underlying molecular mechanism is related to activating the nuclear factor E2-related factor 2 (Nrf2)/antioxidant response element (ARE) antioxidative stress pathway. The following findings were obtained: (1) The treatment of glomerular mesangial cells (GMCs) with high glucose (HG) decreased CKIP-1 levels in a time-dependent manner; (2) CKIP-1 overexpression dramatically reduced fibronectin (FN) and intercellular adhesionmolecule-1 (ICAM-1) expression. Depletion of CKIP-1 further induced the production of FN and ICAM-1; (3) CKIP-1 promoted the nuclear accumulation, DNA binding, and transcriptional activity of Nrf2. Moreover, CKIP-1 upregulated the expression of Nrf2 downstream genes, heme oxygenase (HO-1) and superoxide dismutase 1 (SOD1); and ultimately decreased the levels of reactive oxygen species (ROS). The molecular mechanisms clarify that the advantageous effect of CKIP-1 on DN are well connected with the activation of the Nrf2/ARE antioxidative stress pathway. PMID:27481061

  17. Characterization of the oligodeoxynucleotide-mediated inhibition of interferon-gamma-induced major histocompatibility complex class I and intercellular adhesion molecule-1.

    Science.gov (United States)

    Ramanathan, M; Lantz, M; MacGregor, R D; Garovoy, M R; Hunt, C A

    1994-10-01

    The major histocompatibility complex (MHC) Class I and II genes and intercellular adhesion molecule-1 (ICAM-1) are regulated by interferon-gamma in a variety of cell types. We have previously shown that the oligodeoxynucleotide 5'-GGG GTT GGT TGT GTT GGG TGT TGT GT-RNH2 (oligo I) inhibits the interferon-gamma-mediated enhancement of MHC Class I and ICAM-1 proteins in the K562 cell line. We have now investigated the mechanism of action of oligo I and report that it acts by inhibiting the binding of interferon-gamma to cells. We also show that the dose-response curves, the selectivity profile, and the kinetics of oligo I are consistent with this novel mechanism of action. The dose-response curves for oligo I, obtained using antibodies against the MHC Class I heavy chain, beta 2-microglobulin, or ICAM-1, are almost superimposable at each observation time. MHC Class I induction by 6400 units/ml interferon-alpha or interferon-beta or ICAM-1 enhancement by 800 units/ml tumor necrosis factor-alpha is not inhibited by oligo I. However, the synergistic induction of MHC Class I by mixtures of tumor necrosis factor-alpha and interferon-gamma is inhibited. Oligo I belongs to a class of active oligodeoxynucleotides that inhibits interferon-gamma-induced MHC Class I and ICAM-1 in K562 cells. The activity and potency is sequence-dependent, but remarkably different sequences can have comparable effects. The activity of oligo I in the HeLa S3 cell line inhibits the interferon-gamma-mediated enhancement of both ICAM-1 and MHC Class II DR and the interferon-gamma-mediated reduction in transferrin receptor expression. Thus, oligo I appears to specifically inhibit interferon-gamma-induced changes in protein expression, which is consistent with oligo I acting at an early step(s) in the induction process. Taken together, our results show that oligo I exerts its effects by inhibiting the association of interferon-gamma with the cell surface, which is a novel mechanism of action for

  18. Retinal Vascular Endothelial Growth Factor Induces Intercellular Adhesion Molecule-1 and Endothelial Nitric Oxide Synthase Expression and Initiates Early Diabetic Retinal Leukocyte Adhesion in Vivo

    OpenAIRE

    Joussen, Antonia M; Poulaki, Vassiliki; Qin, Wenying; Kirchhof, Bernd; Mitsiades, Nicholas; Wiegand, Stanley J.; Rudge, John; Yancopoulos, George D.; Adamis, Anthony P.

    2002-01-01

    Leukocyte adhesion to the diabetic retinal vasculature results in early blood-retinal barrier breakdown, capillary nonperfusion, and endothelial cell injury and death. Previous work has shown that intercellular adhesion molecule-1 (ICAM-1) and CD18 are required for these processes. However the relevant in vivo stimuli for ICAM-1 and CD18 expression in diabetes remain unknown. The current study investigated the causal role of endogenous vascular endothelial growth factor (VEGF) and nitric oxid...

  19. Induction of benzo[a]pyrene Mono-oxygenase in liver cell culture by the photochemical generation of active oxygen species. Evidence for the involvement of singlet oxygen and the formation of a stable inducing intermediate.

    Science.gov (United States)

    Paine, A J

    1976-07-15

    1. The photochemical generation of excited states of oxygen in liver cell culture by the mild ilumination of culture medium containing riboflavin, results in stimulation of benzo[a]pyrene 3-mono-oxygenase, a cytochrome P-450-linked mono-oxygenase. 2. The same large increase in mono-oxygenase activity was found when medium containing riboflavin was illuminated in the absence of cells and then stored in the dark for 24h before contact with the cells. From this it may be inferred that stimulation is due to the formation of a stable inducer in the culture medium. Further experiments indicate that the stable inducer is due to the photo-oxidation of an amino acid. 3. Evidence that singlet oxygen is responsible for initiating the stimulation of the mono-oxygenase is based on the use of molecules that scavenge particular active oxygen species. Of all the scavengers tested, only those that scavenge single oxygen inhibited the stimulation. 4. A hypothesis is developed to relate the stimulation of the mono-oxygenase by singlet oxygen in cultured cells to the regulation of the cytochrome P-450 enzyme system in vivo. It is suggested that single oxygen generation within cells may be a common factor linking the many structurally diverse inducers of the enzyme system. PMID:962887

  20. Oral exposure to environmental pollutant benzo[a]pyrene impacts the intestinal epithelium and induces gut microbial shifts in murine model

    Science.gov (United States)

    Ribière, Céline; Peyret, Pierre; Parisot, Nicolas; Darcha, Claude; Déchelotte, Pierre J.; Barnich, Nicolas; Peyretaillade, Eric; Boucher, Delphine

    2016-01-01

    Gut microbiota dysbiosis are associated with a wide range of human diseases, including inflammatory bowel diseases. The physiopathology of these diseases has multifactorial aetiology in which environmental factors, particularly pollution could play a crucial role. Among the different pollutants listed, Polycyclic Aromatic Hydrocarbons (PAHs) are subject to increased monitoring due to their wide distribution and high toxicity on Humans. Here, we used 16S rRNA gene sequencing to investigate the impact of benzo[a]pyrene (BaP, most toxic PAH) oral exposure on the faecal and intestinal mucosa-associated bacteria in C57BL/6 mice. Intestinal inflammation was also evaluated by histological observations. BaP oral exposure significantly altered the composition and the abundance of the gut microbiota and led to moderate inflammation in ileal and colonic mucosa. More severe lesions were observed in ileal segment. Shifts in gut microbiota associated with moderate inflammatory signs in intestinal mucosa would suggest the establishment of a pro-inflammatory intestinal environment following BaP oral exposure. Therefore, under conditions of genetic susceptibility and in association with other environmental factors, exposure to this pollutant could trigger and/or accelerate the development of inflammatory pathologies. PMID:27503127

  1. Benzo(a)pyrene induces oxidative stress, pro-inflammatory cytokines, expression of nuclear factor-kappa B and deregulation of wnt/beta-catenin signaling in colons of BALB/c mice.

    Science.gov (United States)

    Ajayi, Babajide O; Adedara, Isaac A; Farombi, Ebenezer O

    2016-09-01

    The incidence of colonic toxicity has been epidemiologically linked to the consumption of foods contaminated with benzo(a)pyrene (B[a]P). The present study investigated the effects of B[a]P on biomarkers of oxidative stress, inflammation and wnt-signaling in colon of BALB/c mice following exposure to 62.5, 125 and 250 mg/kg of B[a]P for 7 days by oral gavage. Exposure to B[a]P significantly decreased the colonic antioxidant enzymes activities and glutathione level with concomitant significant increase in myeloperoxidase activity, nitric oxide and lipid peroxidation levels. Colon histopathology results showed treatment-related lesions characterized by atrophy, mucosal ulceration and gland erosion in the B[a]P-treated mice. Immunohistochemistry analysis showed that B[a]P treatment increased the protein expression of nuclear factor kappa B, pro-inflammatory cytokines namely tumor necrosis factor alpha and interleukin-1β, as well as cyclooxygenase-2 and inducible nitric oxide synthase in the mice colon. Altered canonical wnt-signaling was confirmed by strong diaminobenzidine staining for p38 mitogen activated protein kinase, β-catenin expression and absence of adenomatous polyposis coli following B[a]P administration. The present data highlight that exposure to B[a]P induces colon injury via induction of oxidative and nitrosative stress, inflammatory biomarkers and dsyregulation wnt/β-catenin signaling, thus confirming the role of B[a]P in the pathogenesis of colonic toxicity. PMID:27338711

  2. The ERCC2/XPD Lys751Gln polymorphism affects DNA repair of benzo[a]pyrene induced damage, tested in an in vitro model.

    Science.gov (United States)

    Xiao, Sha; Cui, Su; Lu, Xiaobo; Guan, Yangyang; Li, Dandan; Liu, Qiufang; Cai, Yuan; Jin, Cuihong; Yang, Jinghua; Wu, Shengwen; van der Straaten, Tahar

    2016-08-01

    Nucleotide excision repair (NER) is an important defense mechanism of the body to exogenous carcinogens and mutagens, such as benzo[a]pyrene (B[a]P). Genetic polymorphisms in ERCC2/XPD, a critical element in NER, are thought to be associated with individual's cancer susceptibility. Although ERCC2/XPD Lys751Gln (rs13181) is the most studied polymorphism, the impact of this polymorphism on DNA repair capacity to carcinogen remains unclear. In the present study, cDNA clones carrying different genotypes of ERCC2/XPD (Lys751Gln) were introduced into an ERCC2/XPD deficient cell line (UV5) in a well-controlled biological system. After B[a]P treatment, cell growth inhibition rates and DNA damage levels in all cells were detected respectively. As expected, we found that the DNA repair capacity in UV5 cells was restored to levels similar to wildtype parent AA8 cells upon introduction of the cDNA clone of ERCC2/XPD (Lys751). Interestingly, after B[a]P treatment, transfected cells expressing variant ERCC2/XPD (751Gln) showed an enhanced cellular sensitivity and a diminished DNA repair capacity. The wildtype genotype AA (Lys) was found to be associated with a higher DNA repair capacity as compared to its polymorphic genotype CC (Gln). These data indicate that ERCC2/XPD Lys751Gln polymorphism affects DNA repair capacity after exposure to environmental carcinogens such as B[a]P in this well-controlled in vitro system and could act as a biomarker to increase the predictive value to develop cancer. PMID:27139774

  3. Intercellular bridges in vertebrate gastrulation.

    Directory of Open Access Journals (Sweden)

    Luca Caneparo

    Full Text Available The developing zebrafish embryo has been the subject of many studies of regional patterning, stereotypical cell movements and changes in cell shape. To better study the morphological features of cells during gastrulation, we generated mosaic embryos expressing membrane attached Dendra2 to highlight cellular boundaries. We find that intercellular bridges join a significant fraction of epiblast cells in the zebrafish embryo, reaching several cell diameters in length and spanning across different regions of the developing embryos. These intercellular bridges are distinct from the cellular protrusions previously reported as extending from hypoblast cells (1-2 cellular diameters in length or epiblast cells (which were shorter. Most of the intercellular bridges were formed at pre-gastrula stages by the daughters of a dividing cell maintaining a membrane tether as they move apart after mitosis. These intercellular bridges persist during gastrulation and can mediate the transfer of proteins between distant cells. These findings reveal a surprising feature of the cellular landscape in zebrafish embryos and open new possibilities for cell-cell communication during gastrulation, with implications for modeling, cellular mechanics, and morphogenetic signaling.

  4. Single-Walled Carbon Nanotube (SWCNT-induced interstitial fibrosis in the lungs of rats is associated with increased levels of PDGF mRNA and the formation of unique intercellular carbon structures that bridge alveolar macrophages In Situ

    Directory of Open Access Journals (Sweden)

    Bermudez Edilberto

    2006-11-01

    Full Text Available Abstract Background Nanotechnology is a rapidly advancing industry with many new products already available to the public. Therefore, it is essential to gain an understanding of the possible health risks associated with exposure to nanomaterials and to identify biomarkers of exposure. In this study, we investigated the fibrogenic potential of SWCNT synthesized by chemical vapor deposition using cobalt (Co and molybdenum (Mo as catalysts. Following a single oropharyngeal aspiration of SWCNT in rats, we evaluated lung histopathology, cell proliferation, and growth factor mRNAs at 1 and 21 days post-exposure. Comparisons were made to vehicle alone (saline containing a biocompatible nonionic surfactant, inert carbon black (CB nanoparticles, or vanadium pentoxide (V2O5 as a known inducer of fibrosis. Results SWCNT or CB caused no overt inflammatory response at 1 or 21 days post-exposure as determined by histopathology and evaluation of cells (>95% macrophages in bronchoalveolar lavage (BAL fluid. However, SWCNT induced the formation of small, focal interstitial fibrotic lesions within the alveolar region of the lung at 21 days. A small fraction of alveolar macrophages harvested by BAL from the lungs of SWCNT-exposed rats at 21 days were bridged by unique intercellular carbon structures that extended into the cytoplasm of each macrophage. These "carbon bridge" structures between macrophages were also observed in situ in the lungs of SWCNT-exposed rats. No carbon bridges were observed in CB-exposed rats. SWCNT caused cell proliferation only at sites of fibrotic lesion formation as measured by bromodeoxyuridine uptake into alveolar cells. SWCNT increased platelet-derived growth factor (PDGF-A, PDGF-B, and PDGF-C mRNA levels significantly at 1 day as measured by Taqman quantitative real-time RT-PCR. At 21 days, SWCNT did not increase any mRNAs evaluated, while V2O5 significantly increased mRNAs encoding PDGF-A, -B, and -C chains, PDGF-Rα, osteopontin

  5. Aldosterone stimulates nuclear factor-kappa B activity and transcription of intercellular adhesion molecule-1 and connective tissue growth factor in rat mesangial cells via serum- and glucocorticoid-inducible protein kinase-1.

    Science.gov (United States)

    Terada, Yoshio; Ueda, Satoko; Hamada, Kazu; Shimamura, Yoshiko; Ogata, Koji; Inoue, Kosuke; Taniguchi, Yoshinori; Kagawa, Toru; Horino, Taro; Takao, Toshihiro

    2012-02-01

    Several clinical and experimental data support the hypothesis that aldosterone contributes to the progression of renal injury. To determine the signaling pathway of aldosterone in relation to fibrosis and inflammation in mesangial cells, we investigated the effects of aldosterone on expression and activation of serum- and glucocorticoid-inducible protein kinase-1 (SGK1), the activation of nuclear factor-kappa B (NF-κB activation, and the expressions of intercellular adhesion molecule-1 (ICAM-1) and connective tissue growth factor (CTGF). Aldosterone stimulated SGK1 expression, phosphorylation (Ser-256), and kinase activity. The increments of phosphorylation and expression of SGK1 induced by aldosterone were inhibited by mineralocorticoid receptor (MR) inhibitor (eplerenone). Aldosterone stimulated NF-κB activity measured by NF-κB responsive elements, luciferase assay, and the levels of inhibitor of kappa B (IκB) phosphorylation. This aldosterone-induced activation of NF-κB was inhibited by the transfection of dominant-negative SGK1. Furthermore, aldosterone augmented the promoter activities and protein expressions of ICAM-1 and CTGF. The effects of aldosterone on ICAM-1 and CTGF promoter activities and protein expressions were inhibited by the transfection of dominant-negative SGK1 and dominant-negative IκBα. We also found that the MR antagonist significantly ameliorated the glomerular injury and enhancements in SGK1, ICAM-1, and CTGF expressions induced by 1% sodium chloride and aldosterone in vivo. In conclusion, our findings suggest that aldosterone stimulates ICAM-1 and CTGF transcription via activation of SGK1 and NF-κB, which may be involved in the progression of aldosterone-induced mesangial fibrosis and inflammation. MR antagonists may serve as useful therapeutic targets for the treatment of glomerular inflammatory disease.

  6. Electrochemical detection of benzo(a)pyrene and related DNA damage using DNA/hemin/nafion–graphene biosensor

    International Nuclear Information System (INIS)

    Graphical abstract: A novel electrochemical biosensor, DNA/hemin/nafion–graphene/GCE, was constructed to quantitatively study the DNA damage induced by the metabolite of benzo(a)pyrene in the presence of H2O2. - Highlights: • Construction of a novel DNA/hemin/nafion-graphene/GCE biosensor. • DNA damage induced by the benzo(a)pyrene metabolite was detected. • DPV analysis of benzo(a)pyrene provided a quantitative estimate of DNA damage. • Hemin/H2O2 system could mimic the cytochrome P450 to metabolize benzo(a)pyrene. - Abstract: A novel electrochemical biosensor, DNA/hemin/nafion–graphene/GCE, was constructed for the analysis of the benzo(a)pyrene PAH, which can produce DNA damage induced by a benzo(a)pyrene (BaP) enzyme-catalytic product. This biosensor was assembled layer-by-layer, and was characterized with the use of cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and atomic force microscopy. Ultimately, it was demonstrated that the hemin/nafion–graphene/GCE was a viable platform for the immobilization of DNA. This DNA biosensor was treated separately in benzo(a)pyrene, hydrogen peroxide (H2O2) and in their mixture, respectively, and differential pulse voltammetry (DPV) analysis showed that an oxidation peak was apparent after the electrode was immersed in H2O2. Such experiments indicated that in the presence of H2O2, hemin could mimic cytochrome P450 to metabolize benzo(a)pyrene, and a voltammogram of its metabolite was recorded. The DNA damage induced by this metabolite was also detected by electrochemical impedance and ultraviolet spectroscopy. Finally, a novel, indirect DPV analytical method for BaP in aqueous solution was developed based on the linear metabolite versus BaP concentration plot; this method provided a new, indirect, quantitative estimate of DNA damage

  7. Mutations Induced by Benzo[a]pyrene and Dibenzo[a,l]pyrene in lacI Transgenic B6C3F1 Mouse Lung Result from Stable DNA Adducts

    Science.gov (United States)

    Dibenzo[a,l]pyrene (DB[a,l]P) and benzo[a]pyrene (B[a]P) are carcinogenic polycyclic aromatic hydrocarbons (PAH) that are each capable of forming a variety of covalent adducts with DNA. Some of the DNA adducts formed by these PAHs have been demonstrated to spontaneously depurina...

  8. Screening of anti-hypoxia/reoxygenation agents by an in vitro method. Part 2: Inhibition of tyrosine kinase activation prevented hypoxia/reoxygenation-induced injury in endothelial gap junctional intercellular communication.

    Science.gov (United States)

    Zhang, Y W; Morita, I; Zhang, L; Shao, G; Yao, X S; Murota, S

    2000-03-01

    In this study, we demonstrated that hypoxia/reoxygenation (H/R) induced an injury in gap junctional intercellular communication (GJIC) after 2 h of reoxygenation in cultured HUVEC. Free radical scavenger (DMSO) and antioxidant (SOD) did not prevent this GJIC injury at all. Protein kinase C inhibitor (calphostin C) partly blocked this injury. However, the protein tyrosine kinase (PTK) inhibitor genistein completely inhibited this GJIC injury. Compounds 1 [laxogenin-3-O-alpha-L-arabinosyl-(1-->6)- beta-D-glucopyranoside], 2 (macrostemososide A), 3 [laxogenin-3-O-beta-D-xylopyranosyl-(1-->4)-alpha- L-arabinopyranosyl-(1-->6)-beta-D-glucopyranoside], 4 (chinenoside II), 5 (beta-sitosterol), 6 (daucosterine), 7 (ginsenoside-Rd), 29 (isocumarine), 52 (icariin), 53 (icariside), and 54 (icaritin), which showed obvious influence on H/R-induced PTK activation as stated in Part 1 (except 1), were explored for their effects on GJIC. The results showed that compounds 2-7 and 52-57 partly protected H/R-induced GJIC injury. Compounds 5 and 6 (especially 5), which showed the strongest inhibitory effects on PTK activation, completely blocked H/R-provoked GJIC injury. Compound 1, which did not influence PTK activation, failed to prevent this GJIC injury. In contrast, compound 29, which significantly promoted PTK activation, enhanced this H/R-induced GJIC injury further. Western blotting of connexin 43, an important gap junctional protein for modulating GJIC in HUVEC, revealed that interference with the gap junctional protein might be the most direct mechanism for compounds 2, 5, 29, and 53 to affect H/R-injured GJIC. PMID:10763583

  9. hREV3 is essential for error-prone translesion synthesis past UV or benzo[a]pyrene diol epoxide-induced DNA lesions in human fibroblasts

    International Nuclear Information System (INIS)

    In S. cerevisiae, the REV3 gene, encoding the catalytic subunit of polymerase zeta, is involved in translesion synthesis and required for the production of mutations induced by ultraviolet radiation (UV) photoproducts and other DNA fork-blocking lesions, and for the majority of spontaneous mutations. To determine whether hREV3, the human homolog of yeast REV3, is similarly involved in error-prone translesion synthesis past UV photoproducts and other lesions that block DNA replication, an hREV3 antisense construct under the control of the TetP promoter was transfected into an infinite life span human fibroblast cell strain that expresses a high level of tTAk, the activator of that promoter. Three transfectant strains expressing high levels of hREV3 antisense RNA were identified and compared with their parental cell strain for sensitivity to the cytotoxic and mutagenic effects of UV. The three hREV3 antisense-expressing cell strains were not more sensitive than the parental strain to the cytotoxic effect of UV, but the frequency of mutants induced by UV in their HPRT gene was significantly reduced, i.e. to 14% that of the parent. Two of these hREV3 antisense-expressing cell strains were compared with the parental strain for sensitivity to (±)-7β,8α-dihydroxy-9α,10α-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE). They were not more sensitive than the parent strain to the cytotoxic effect of BPDE, but the frequency of mutants induced was significantly reduced, i.e. in one strain, to 17% that of the parent, and in the other, to 24%. DNA sequencing showed that the kinds of mutations induced by BPDE in the parental and the derivative strains did not differ and were similar to those found previously with finite life span human fibroblasts. The data strongly support the hypothesis that hRev3 plays a critical role in the induction of mutations by UV or BPDE. Because the level of hRev3 protein in human fibroblasts is below the level of antibody detection, it was not

  10. Hypoxia diminishes the detoxification of the environmental mutagen benzo[a]pyrene

    NARCIS (Netherlands)

    Schults, Marten A.; Sanen, Kathleen; Godschalk, Roger W.; Theys, Jan; van Schooten, Frederik J.; Chiu, Roland K.

    2014-01-01

    Hypoxia promotes genetic instability and is therefore an important factor in carcinogenesis. We have previously shown that activation of the hypoxia responsive transcription factor HIF alpha can enhance the mutagenic phenotype induced by the environmental mutagen benzo[a]pyrene (BaP). To further elu

  11. Topological, functional, and dynamic properties of the protein interaction networks rewired by benzo(a)pyrene

    Energy Technology Data Exchange (ETDEWEB)

    Ba, Qian [Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai (China); Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing (China); Li, Junyang; Huang, Chao [Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai (China); Li, Jingquan; Chu, Ruiai [Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai (China); Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing (China); Wu, Yongning, E-mail: wuyongning@cfsa.net.cn [Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing (China); Wang, Hui, E-mail: huiwang@sibs.ac.cn [Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai (China); Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing (China); School of Life Science and Technology, ShanghaiTech University, Shanghai (China)

    2015-03-01

    Benzo(a)pyrene is a common environmental and foodborne pollutant that has been identified as a human carcinogen. Although the carcinogenicity of benzo(a)pyrene has been extensively reported, its precise molecular mechanisms and the influence on system-level protein networks are not well understood. To investigate the system-level influence of benzo(a)pyrene on protein interactions and regulatory networks, a benzo(a)pyrene-rewired protein interaction network was constructed based on 769 key proteins derived from more than 500 literature reports. The protein interaction network rewired by benzo(a)pyrene was a scale-free, highly-connected biological system. Ten modules were identified, and 25 signaling pathways were enriched, most of which belong to the human diseases category, especially cancer and infectious disease. In addition, two lung-specific and two liver-specific pathways were identified. Three pathways were specific in short and medium-term networks (< 48 h), and five pathways were enriched only in the medium-term network (6 h–48 h). Finally, the expression of linker genes in the network was validated by Western blotting. These findings establish the overall, tissue- and time-specific benzo(a)pyrene-rewired protein interaction networks and provide insights into the biological effects and molecular mechanisms of action of benzo(a)pyrene. - Highlights: • Benzo(a)pyrene induced scale-free, highly-connected protein interaction networks. • 25 signaling pathways were enriched through modular analysis. • Tissue- and time-specific pathways were identified.

  12. Topological, functional, and dynamic properties of the protein interaction networks rewired by benzo(a)pyrene

    International Nuclear Information System (INIS)

    Benzo(a)pyrene is a common environmental and foodborne pollutant that has been identified as a human carcinogen. Although the carcinogenicity of benzo(a)pyrene has been extensively reported, its precise molecular mechanisms and the influence on system-level protein networks are not well understood. To investigate the system-level influence of benzo(a)pyrene on protein interactions and regulatory networks, a benzo(a)pyrene-rewired protein interaction network was constructed based on 769 key proteins derived from more than 500 literature reports. The protein interaction network rewired by benzo(a)pyrene was a scale-free, highly-connected biological system. Ten modules were identified, and 25 signaling pathways were enriched, most of which belong to the human diseases category, especially cancer and infectious disease. In addition, two lung-specific and two liver-specific pathways were identified. Three pathways were specific in short and medium-term networks (< 48 h), and five pathways were enriched only in the medium-term network (6 h–48 h). Finally, the expression of linker genes in the network was validated by Western blotting. These findings establish the overall, tissue- and time-specific benzo(a)pyrene-rewired protein interaction networks and provide insights into the biological effects and molecular mechanisms of action of benzo(a)pyrene. - Highlights: • Benzo(a)pyrene induced scale-free, highly-connected protein interaction networks. • 25 signaling pathways were enriched through modular analysis. • Tissue- and time-specific pathways were identified

  13. Electrochemical detection of benzo(a)pyrene and related DNA damage using DNA/hemin/nafion–graphene biosensor

    Energy Technology Data Exchange (ETDEWEB)

    Ni, Yongnian, E-mail: ynni@ncu.edu.cn [State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047 (China); Department of Chemistry, Nanchang University, Nanchang 330031 (China); Wang, Pingping; Song, Haiyan [Department of Chemistry, Nanchang University, Nanchang 330031 (China); Lin, Xiaoyun [State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047 (China); Department of Chemistry, Nanchang University, Nanchang 330031 (China); Kokot, Serge, E-mail: s.kokot@qut.edu.au [School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology, Brisbane 4001 (Australia)

    2014-04-01

    Graphical abstract: A novel electrochemical biosensor, DNA/hemin/nafion–graphene/GCE, was constructed to quantitatively study the DNA damage induced by the metabolite of benzo(a)pyrene in the presence of H{sub 2}O{sub 2}. - Highlights: • Construction of a novel DNA/hemin/nafion-graphene/GCE biosensor. • DNA damage induced by the benzo(a)pyrene metabolite was detected. • DPV analysis of benzo(a)pyrene provided a quantitative estimate of DNA damage. • Hemin/H{sub 2}O{sub 2} system could mimic the cytochrome P450 to metabolize benzo(a)pyrene. - Abstract: A novel electrochemical biosensor, DNA/hemin/nafion–graphene/GCE, was constructed for the analysis of the benzo(a)pyrene PAH, which can produce DNA damage induced by a benzo(a)pyrene (BaP) enzyme-catalytic product. This biosensor was assembled layer-by-layer, and was characterized with the use of cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and atomic force microscopy. Ultimately, it was demonstrated that the hemin/nafion–graphene/GCE was a viable platform for the immobilization of DNA. This DNA biosensor was treated separately in benzo(a)pyrene, hydrogen peroxide (H{sub 2}O{sub 2}) and in their mixture, respectively, and differential pulse voltammetry (DPV) analysis showed that an oxidation peak was apparent after the electrode was immersed in H{sub 2}O{sub 2}. Such experiments indicated that in the presence of H{sub 2}O{sub 2}, hemin could mimic cytochrome P450 to metabolize benzo(a)pyrene, and a voltammogram of its metabolite was recorded. The DNA damage induced by this metabolite was also detected by electrochemical impedance and ultraviolet spectroscopy. Finally, a novel, indirect DPV analytical method for BaP in aqueous solution was developed based on the linear metabolite versus BaP concentration plot; this method provided a new, indirect, quantitative estimate of DNA damage.

  14. Intercellular adhesion molecule-1 clusters during osteoclastogenesis

    NARCIS (Netherlands)

    V. Bloemen; T.J. de Vries; T. Schoenmaker; V. Everts

    2009-01-01

    Adhesion between osteoblasts and osteoclast precursors is established via an interaction involving intercellular adhesion molecule-1 (ICAM-1) on osteoblasts and leukocyte function-associated antigen-1 (LFA-1) on osteoclast precursors. The latter cells also express ICAM-1, but little is known about t

  15. Effects of polar cortical cytoskeleton and unbalanced cortical surface tension on intercellular bridge thinning during cytokinesis

    Institute of Scientific and Technical Information of China (English)

    Li Wang; Mei-Wen An; Xiao-Na Li; Fang Yang; Yang Liu

    2011-01-01

    To probe the contributions of polar cortical cytoskeleton and the surface tension of daughter cells to intercellular bridgethinning dynamics during cytokinesis,we applied cytochalasin D (CD) or colchicine (COLC) in a highly localized manner to polar regions of dividing normal rat kidney (NRK) cells.We observed cellular morphological changes and analyzed the intercellular bridge thinning trajectories of dividing cells with different polar cortical characteristics.Global blebbistatin (BS) application was used to obtain cells losing active contractile force groups.Our results show that locally released CD or colchicine at the polar region caused inhibition of cytokinesis before ingression.Similar treatment at phases after ingression allowed completion of cytokinesis but dramatically influenced the trajectories of intercellular bridge thinning.Disturbing single polar cortical actin induced transformation of the intercellular bridge thinning process,and polar cortical tension controlled deformation time of intercellular bridges.Our study provides a feasible framework to induce and analyze the effects of local changes in mechanical properties of cellular components on single cellular cytokinesis.

  16. Development of schizogenous intercellular spaces in plants

    Directory of Open Access Journals (Sweden)

    Kimitsune eIshizaki

    2015-07-01

    Full Text Available Gas exchange is essential for multicellular organisms. In contrast to the circulatory systems of animals, land plants have tissues with intercellular spaces (ICSs, called aerenchyma, that are critical for efficient gas exchange. Plants form ICSs by two different mechanisms: schizogeny, where localized cell separation creates spaces; and lysogeny, where cells die to create intercellular spaces. In schizogenous ICS formation, specific molecular mechanisms regulate the sites of cell separation and coordinate extensive reorganization of cell walls. Emerging evidence suggests the involvement of extracellular signaling, mediated by peptide ligands and leucine-rich repeat receptor-like kinases, in the regulation of cell wall remodeling during cell separation. Recent work on the liverwort Marchantia polymorpha has demonstrated a critical role for a plasma membrane-associated plant U-box E3 ubiquitin ligase in ICS formation. In this review, I discuss the mechanism of schizogenous ICS formation, focusing on the potential role of extracellular signaling in the regulation of cell separation.

  17. Characterizing Intercellular Signaling Peptides in Drug Addiction

    OpenAIRE

    Romanova, Elena V.; Hatcher, Nathan G.; Rubakhin, Stanislav S.; Sweedler, Jonathan V.

    2008-01-01

    Intercellular signaling peptides (SPs) coordinate the activity of cells and influence organism behavior. SPs, a chemically and structurally diverse group of compounds responsible for transferring information between neurons, are broadly involved in neural plasticity, learning and memory, as well as in drug addiction phenomena. Historically, SP discovery and characterization has tracked advances in measurement capabilities. Today, a suite of analytical technologies is available to investigate ...

  18. Angiogenic Effect of Intercellular Adhesion Molecule-1

    Institute of Scientific and Technical Information of China (English)

    DENG Chenguo; ZHANG Duanlian; SHAN Shengguo; WU Jingwen; YANG Hong; YU Ying

    2007-01-01

    In order to investigate the angiogenic effect of intercellular adhesion molecule-1 (ICAM-1), two parts of experiment were performed. Chick embryo chorioallantoic membrane (CAM) assay was used for in vivo angiogenic research. The chick embryos were divided into 4 groups: ICAM-1 group (divided into 3 subgroups, Ⅰ, Ⅱ and Ⅲ) for screening the angiogenic effect of ICAM-1 by adding different concentrations of ICAM-1 (0.1, 0.2 and 0.3 μg/μL) 5 μL into the chick embryo CAMs on the day 10 after incubation for every subgroup; Anti-ICAM-1 group A (divided into 2 subgroups, Ⅰ and Ⅱ) by adding different concentrations of Anti-ICAM-1 (1:100, 1:50) 5 μL into the chick embryo CAMs on the day 10 after incubation for every subgroup to evaluate the effect of ICAM-1 on the survival of microvessels through observing whether Anti-ICAM-1 could induce involution of the microvessels on CAMs; Anti-ICAM-1 group B (divided into 2 subgroups, Ⅰ and Ⅱ ) by adding different concentrations of Anti-ICAM-1 (1:100, 1:50) 5 μL into the chick embryo CAMs on the day 6 after incubation for every subgroup to evaluate whether ICAM-1 involved in embryonic angiogenesis through observing the growth of microvessels on CAMs; Control group: ICAM-1 or Anti-ICAM-1 was substituted by PBS 5 μL on the day 10 or day 6 after incubation. Three days later, the CAMs were photographed in vivo, excised, sectioned and the number of microvessels was counted. In ICAM-1 group, there was increased number of microvessels arranged radially with "spoked-wheel" pattern around the gelatin sponges. The new microvessels growing perpendicularly to gelatin sponges were observed. The number of the microvessels growing in the CAM mesenchymes around the sponges in 3 subgroups was higher than that in control group (P<0.01), however, there was no significant difference among the 3 subgroups (P>0.05). In anti-ICAM-1 group A, the radially arranged microvessels were very unclear around the sponges contrast to that of ICAM

  19. Contribution of host intracellular transport machineries to intercellular movement of turnip mosaic virus.

    Science.gov (United States)

    Agbeci, Maxime; Grangeon, Romain; Nelson, Richard S; Zheng, Huanquan; Laliberté, Jean-François

    2013-01-01

    The contribution of different host cell transport systems in the intercellular movement of turnip mosaic virus (TuMV) was investigated. To discriminate between primary infections and secondary infections associated with the virus intercellular movement, a gene cassette expressing GFP-HDEL was inserted adjacent to a TuMV infectious cassette expressing 6K₂:mCherry, both within the T-DNA borders of the binary vector pCambia. In this system, both gene cassettes were delivered to the same cell by a single binary vector and primary infection foci emitted green and red fluorescence while secondarily infected cells emitted only red fluorescence. Intercellular movement was measured at 72 hours post infiltration and was estimated to proceed at an average rate of one cell being infected every three hours over an observation period of 17 hours. To determine if the secretory pathway were important for TuMV intercellular movement, chemical and protein inhibitors that blocked both early and late secretory pathways were used. Treatment with Brefeldin A or Concanamycin A or expression of ARF1 or RAB-E1d dominant negative mutants, all of which inhibit pre- or post-Golgi transport, reduced intercellular movement by the virus. These treatments, however, did not inhibit virus replication in primary infected cells. Pharmacological interference assays using Tyrphostin A23 or Wortmannin showed that endocytosis was not important for TuMV intercellular movement. Lack of co-localization by endocytosed FM4-64 and Ara7 (AtRabF2b) with TuMV-induced 6K₂-tagged vesicles further supported this conclusion. Microfilament depolymerizing drugs and silencing expression of myosin XI-2 gene, but not myosin VIII genes, also inhibited TuMV intercellular movement. Expression of dominant negative myosin mutants confirmed the role played by myosin XI-2 as well as by myosin XI-K in TuMV intercellular movement. Using this dual gene cassette expression system and transport inhibitors, components of the

  20. Contribution of host intracellular transport machineries to intercellular movement of turnip mosaic virus.

    Directory of Open Access Journals (Sweden)

    Maxime Agbeci

    Full Text Available The contribution of different host cell transport systems in the intercellular movement of turnip mosaic virus (TuMV was investigated. To discriminate between primary infections and secondary infections associated with the virus intercellular movement, a gene cassette expressing GFP-HDEL was inserted adjacent to a TuMV infectious cassette expressing 6K₂:mCherry, both within the T-DNA borders of the binary vector pCambia. In this system, both gene cassettes were delivered to the same cell by a single binary vector and primary infection foci emitted green and red fluorescence while secondarily infected cells emitted only red fluorescence. Intercellular movement was measured at 72 hours post infiltration and was estimated to proceed at an average rate of one cell being infected every three hours over an observation period of 17 hours. To determine if the secretory pathway were important for TuMV intercellular movement, chemical and protein inhibitors that blocked both early and late secretory pathways were used. Treatment with Brefeldin A or Concanamycin A or expression of ARF1 or RAB-E1d dominant negative mutants, all of which inhibit pre- or post-Golgi transport, reduced intercellular movement by the virus. These treatments, however, did not inhibit virus replication in primary infected cells. Pharmacological interference assays using Tyrphostin A23 or Wortmannin showed that endocytosis was not important for TuMV intercellular movement. Lack of co-localization by endocytosed FM4-64 and Ara7 (AtRabF2b with TuMV-induced 6K₂-tagged vesicles further supported this conclusion. Microfilament depolymerizing drugs and silencing expression of myosin XI-2 gene, but not myosin VIII genes, also inhibited TuMV intercellular movement. Expression of dominant negative myosin mutants confirmed the role played by myosin XI-2 as well as by myosin XI-K in TuMV intercellular movement. Using this dual gene cassette expression system and transport inhibitors

  1. Free radicals of benzo(a)pyrene and derivatives.

    OpenAIRE

    Sullivan, P D

    1985-01-01

    The evidence for biological involvement, the spectroscopic properties (especially EPR), and the reactions, of free radicals derived from benzo(a)pyrene and its methylated, hydroxylated, and fluorinated derivatives are reviewed.

  2. Extracellular ultrathin fibers sensitive to intracellular reactive oxygen species: Formation of intercellular membrane bridges

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Se-Hui; Park, Jin-Young; Joo, Jung-Hoon; Kim, Young-Myeong; Ha, Kwon-Soo, E-mail: ksha@kangwon.ac.kr

    2011-07-15

    Membrane bridges are key cellular structures involved in intercellular communication; however, dynamics for their formation are not well understood. We demonstrated the formation and regulation of novel extracellular ultrathin fibers in NIH3T3 cells using confocal and atomic force microscopy. At adjacent regions of neighboring cells, phorbol 12-myristate 13-acetate (PMA) and glucose oxidase induced ultrathin fiber formation, which was prevented by Trolox, a reactive oxygen species (ROS) scavenger. The height of ROS-sensitive ultrathin fibers ranged from 2 to 4 nm. PMA-induced formation of ultrathin fibers was inhibited by cytochalasin D, but not by Taxol or colchicine, indicating that ultrathin fibers mainly comprise microfilaments. PMA-induced ultrathin fibers underwent dynamic structural changes, resulting in formation of intercellular membrane bridges. Thus, these fibers are formed by a mechanism(s) involving ROS and involved in formation of intercellular membrane bridges. Furthermore, ultrastructural imaging of ultrathin fibers may contribute to understanding the diverse mechanisms of cell-to-cell communication and the intercellular transfer of biomolecules, including proteins and cell organelles.

  3. Uptake of 7,12-dimethylbenz(a)anthracene and benzo(a)pyrene in melanin-containing tissues

    Energy Technology Data Exchange (ETDEWEB)

    Roberto, A.; Larsson, B.S. [Uppsala Univ., Dept. of Pharmaceutical Biosciences, Div. of Toxicology, Uppsala (Sweden); Tjaelve, H. [The Swedish Univ. of Agricultural Sciences, Dept. of Pharmacology and Toxicology, Uppsala (Sweden)

    1996-08-01

    It is widely accepted that UV exposure is the main etiological factor for malignant melanoma. Epidemiologic studies, however, have indicated that also chemical carcinogens may be a risk factor for the disease. Polycyclic aromatic hydrocarbons such as 7,12-dimethylbenz(a)anthracene and benzo(a)pyrene represent an important class of carcinogenic chemicals. It is known that 7,12-dimethylbenz(a)anthracene can induce melanotic tumours in various animal species, and human melanocytes in culture have been found to be capable of metabolizing benzo(a)pyrene to its proximate carcinogen benzo(a)pyrene-7,8-diol. In the present study the disposition of {sup 14}C- and {sup 3}H-7,12-dimethylbenz(a)anthracene and {sup 14}C-benzo(a)pyrene was studied in pigmented and albino mice and Syrian golden hamsters by whole-body autoradiography. The results showed pronounced retention of label in the melanin-containing structures of the eyes and the hair follicles in the pigmented animals. The labelling of the corresponding structures in the albino animals was low. Additional experiments showed that 7,12-dimethylbenz(a)anthracene and benzo(a)pyrene as well as some of their metabolites are bound to melanin in vitro. The specific localization of the polycyclic aromatic hydrocarbons in pigmented tissues due to melanin affinity, combined with bioactivating capacity of melanocytes, suggest that these substances may play a role in the induction of malignant melanoma. (au).

  4. Enhanced Synchronization of Intercellular Calcium Oscillations by Noise Contaminated Signals

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ji-Qian; CHEN Han-Shuang; WANG Mao-Sheng

    2008-01-01

    We consider the dynamics of locally coupled calcium oscillation systems, each cell is subjected to extracel-lular contaminated signal, which contains common sub-threshold signal and independent Gaussian noise. It is found that intermediate noise can enhance synchronized oscillations of calcium ions, where the frequency of noise-induced oscilla-tions is matched with the one of sub-threshold external signal. We show that synchronization is enhanced as a result of the entrainment of external signal Furthermore, the effect of coupling strength is considered. We find above-mentioned phenomenon exists only when coupling strength is very small Our findings may exhibit that noise can enhance the detection of feeble external signal through the mechanism of synchronization of intercellular calcium ions.

  5. Stimulating the Release of Exosomes Increases the Intercellular Transfer of Prions.

    Science.gov (United States)

    Guo, Belinda B; Bellingham, Shayne A; Hill, Andrew F

    2016-03-01

    Exosomes are small extracellular vesicles released by cells and play important roles in intercellular communication and pathogen transfer. Exosomes have been implicated in several neurodegenerative diseases, including prion disease and Alzheimer disease. Prion disease arises upon misfolding of the normal cellular prion protein, PrP(C), into the disease-associated isoform, PrP(Sc). The disease has a unique transmissible etiology, and exosomes represent a novel and efficient method for prion transmission. The precise mechanism by which prions are transmitted from cell to cell remains to be fully elucidated, although three hypotheses have been proposed: direct cell-cell contact, tunneling nanotubes, and exosomes. Given the reported presence of exosomes in biological fluids and in the lipid and nucleic acid contents of exosomes, these vesicles represent an ideal mechanism for encapsulating prions and potential cofactors to facilitate prion transmission. This study investigates the relationship between exosome release and intercellular prion dissemination. Stimulation of exosome release through treatment with an ionophore, monensin, revealed a corresponding increase in intercellular transfer of prion infectivity. Conversely, inhibition of exosome release using GW4869 to target the neutral sphingomyelinase pathway induced a decrease in intercellular prion transmission. Further examination of the effect of monensin on PrP conversion revealed that monensin also alters the conformational stability of PrP(C), leading to increased generation of proteinase K-resistant prion protein. The findings presented here provide support for a positive relationship between exosome release and intercellular transfer of prion infectivity, highlighting an integral role for exosomes in facilitating the unique transmissible nature of prions.

  6. Stimulating the Release of Exosomes Increases the Intercellular Transfer of Prions.

    Science.gov (United States)

    Guo, Belinda B; Bellingham, Shayne A; Hill, Andrew F

    2016-03-01

    Exosomes are small extracellular vesicles released by cells and play important roles in intercellular communication and pathogen transfer. Exosomes have been implicated in several neurodegenerative diseases, including prion disease and Alzheimer disease. Prion disease arises upon misfolding of the normal cellular prion protein, PrP(C), into the disease-associated isoform, PrP(Sc). The disease has a unique transmissible etiology, and exosomes represent a novel and efficient method for prion transmission. The precise mechanism by which prions are transmitted from cell to cell remains to be fully elucidated, although three hypotheses have been proposed: direct cell-cell contact, tunneling nanotubes, and exosomes. Given the reported presence of exosomes in biological fluids and in the lipid and nucleic acid contents of exosomes, these vesicles represent an ideal mechanism for encapsulating prions and potential cofactors to facilitate prion transmission. This study investigates the relationship between exosome release and intercellular prion dissemination. Stimulation of exosome release through treatment with an ionophore, monensin, revealed a corresponding increase in intercellular transfer of prion infectivity. Conversely, inhibition of exosome release using GW4869 to target the neutral sphingomyelinase pathway induced a decrease in intercellular prion transmission. Further examination of the effect of monensin on PrP conversion revealed that monensin also alters the conformational stability of PrP(C), leading to increased generation of proteinase K-resistant prion protein. The findings presented here provide support for a positive relationship between exosome release and intercellular transfer of prion infectivity, highlighting an integral role for exosomes in facilitating the unique transmissible nature of prions. PMID:26769968

  7. Intercellular communication lessons in heart failure.

    Science.gov (United States)

    Bang, Claudia; Antoniades, Charalambos; Antonopoulos, Alexios S; Eriksson, Ulf; Franssen, Constantijn; Hamdani, Nazha; Lehmann, Lorenz; Moessinger, Christine; Mongillo, Marco; Muhl, Lars; Speer, Thimoteus; Thum, Thomas

    2015-11-01

    Cell-cell or inter-organ communication allows the exchange of information and messages, which is essential for the coordination of cell/organ functions and the maintenance of homeostasis. It has become evident that dynamic interactions of different cell types play a major role in the heart, in particular during the progression of heart failure, a leading cause of mortality worldwide. Heart failure is associated with compensatory structural and functional changes mostly in cardiomyocytes and cardiac fibroblasts, which finally lead to cardiomyocyte hypertrophy and fibrosis. Intercellular communication within the heart is mediated mostly via direct cell-cell interaction or the release of paracrine signalling mediators such as cytokines and chemokines. However, recent studies have focused on the exchange of genetic information via the packaging into vesicles as well as the crosstalk of lipids and other paracrine molecules within the heart and distant organs, such as kidney and adipose tissue, which might all contribute to the pathogenesis of heart failure. In this review, we discuss emerging communication networks and respective underlying mechanisms which could be involved in cardiovascular disease conditions and further emphasize promising therapeutic targets for drug development.

  8. Prevention of reovirus type 2-induced diabetes-like syndrome in DBA/1 suckling mice by treatment with antibodies against intercellular adhesion molecule-1 and lymphocyte function-associated antigen-1.

    OpenAIRE

    Hayashi, T.; Yamamoto, S.; Onodera, T.

    1995-01-01

    Reovirus type 2-induced diabetes-like syndrome in suckling mice is considered to be an animal model for human insulin-dependent diabetes mellitus. We have previously demonstrated that immunopathologic pancreatic islet cell damage might be relevant to reovirus type 2 infection. In this study the involvement of adhesion molecules in the development of reovirus type 2-induced diabetes-like syndrome was examined. In infected mice infiltration of mononuclear cells mixed with polymorphonuclear leuc...

  9. Modelling of intercellular synchronization in the Drosophila circadian clock

    Institute of Scientific and Technical Information of China (English)

    Wang Jun-Wei; Chen Ai-Min; Zhang Jia-Jun; Yuan Zhan-Jiang; Zhou Tian-Shou

    2009-01-01

    In circadian rhythm generation, intercellular signaling factors are shown to play a crucial role in both sustaining intrinsic cellular rhythmicity and acquiring collective behaviours across a population of circadian neurons. However, the physical mechanism behind their role remains to be fully understood. In this paper, we propose an indirectly coupled multicellular model for the synchronization of Drosophila circadian oscillators combining both intracellular and intercellular dynamics. By simulating different experimental conditions, we find that such an indirect coupling way can synchronize both heterogeneous self-sustained circadian neurons and heterogeneous mutational damped circadian neurons. Moreover, they can also be entrained to ambient light-dark (LD) cycles depending on intercellular signaling.

  10. Phosphatidylinositol-bisphosphate regulates intercellular coupling in cardiac myocytes

    DEFF Research Database (Denmark)

    Hofgaard, Johannes P; Banach, Kathrin; Mollerup, Sarah;

    2008-01-01

    Changes in the lipid composition of cardiac myocytes have been reported during cardiac hypertrophy, cardiomyopathy, and infarction. Because a recent study indicates a relation between low phosphatidylinositol-bisphosphate (PIP(2)) levels and reduced intercellular coupling, we tested the hypothesis...

  11. Expression of a defence-related intercellular barley peroxidase in transgenic tobacco

    DEFF Research Database (Denmark)

    Kristensen, B.K.; Brandt, J.; Bojsen, K.;

    1997-01-01

    Tobacco plants (Nicotiana benthamiana L.) have been transformed with a T-DNA vector construct carrying the cDNA pBH6-301, encoding the major pathogen induced leaf peroxidase (Prx8) of barley, under control of an enhanced CaMV 35S promoter. Progeny from three independent transformants were analyzed...... genetically, phenotypically and biochemically. The T-DNA was steadily inherited through three generations. The barley peroxidase is expressed and sorted to the intercellular space in the transgenic tobacco plants. The peroxidase can be extracted from the intercellular space in two molecular forms from both...... barley and transgenic tobacco. The tobacco expressed forms are indistinguishable from the barley expressed forms as determined by analytical isoelectric focusing (pI 8.5) and Western-blotting. Staining for N-glycosylation showed that one form only was glycosylated. The N-terminus of purified Prx8 from...

  12. 1,4-Naphthoquinones: From Oxidative Damage to Cellular and Inter-Cellular Signaling

    Directory of Open Access Journals (Sweden)

    Lars-Oliver Klotz

    2014-09-01

    Full Text Available Naphthoquinones may cause oxidative stress in exposed cells and, therefore, affect redox signaling. Here, contributions of redox cycling and alkylating properties of quinones (both natural and synthetic, such as plumbagin, juglone, lawsone, menadione, methoxy-naphthoquinones, and others to cellular and inter-cellular signaling processes are discussed: (i naphthoquinone-induced Nrf2-dependent modulation of gene expression and its potentially beneficial outcome; (ii the modulation of receptor tyrosine kinases, such as the epidermal growth factor receptor by naphthoquinones, resulting in altered gap junctional intercellular communication. Generation of reactive oxygen species and modulation of redox signaling are properties of naphthoquinones that render them interesting leads for the development of novel compounds of potential use in various therapeutic settings.

  13. Intercellular calcium signaling occurs between human osteoblasts and osteoclasts and requires activation of osteoclast P2X7 receptors

    DEFF Research Database (Denmark)

    Jørgensen, Niklas R; Henriksen, Zanne; Sørensen, Ole;

    2002-01-01

    Signaling between osteoblasts and osteoclasts is important in bone homeostasis. We previously showed that human osteoblasts propagate intercellular calcium signals via two mechanisms: autocrine activation of P2Y receptors, and gap junctional communication. In the current work we identified...... mechanically induced intercellular calcium signaling between osteoblasts and osteoclasts and among osteoclasts. Intercellular calcium responses in osteoclasts required P2 receptor activation but not gap junctional communication. Pharmacological studies and reverse transcriptase-PCR amplification demonstrated...... that human osteoclasts expressed functional P2Y1 receptors, but, unexpectedly, desensitization of P2Y1 did not block calcium signaling to osteoclasts. We also found that osteoclasts expressed functional P2X7 receptors and showed that pharmacological inhibition of these receptors blocked calcium signaling...

  14. Role of auxin during intercellular infection of Discaria trinervis by Frankia

    Science.gov (United States)

    Imanishi, Leandro; Perrine-Walker, Francine M.; Ndour, Adama; Vayssières, Alice; Conejero, Genevieve; Lucas, Mikaël; Champion, Antony; Laplaze, Laurent; Wall, Luis; Svistoonoff, Sergio

    2014-01-01

    Nitrogen-fixing nodules induced by Frankia in the actinorhizal plant Discaria trinervis result from a primitive intercellular root invasion pathway that does not involve root hair deformation and infection threads. Here, we analyzed the role of auxin in this intercellular infection pathway at the molecular level and compared it with our previous work in the intracellular infected actinorhizal plant Casuarina glauca. Immunolocalisation experiments showed that auxin accumulated in Frankia-infected cells in both systems. We then characterized the expression of auxin transporters in D. trinervis nodules. No activation of the heterologous CgAUX1 promoter was detected in infected cells in D. trinervis. These results were confirmed with the endogenous D. trinervis gene, DtAUX1. However, DtAUX1 was expressed in the nodule meristem. Consistently, transgenic D. trinervis plants containing the auxin response marker DR5:VENUS showed expression of the reporter gene in the meristem. Immunolocalisation experiments using an antibody against the auxin efflux carrier PIN1, revealed the presence of this transporter in the plasma membrane of infected cells. Finally, we used in silico cellular models to analyse auxin fluxes in D. trinervis nodules. Our results point to the existence of divergent roles of auxin in intercellularly- and intracellularly-infected actinorhizal plants, an ancestral infection pathways leading to root nodule symbioses. PMID:25191330

  15. Role of auxin during intercellular infection of Discaria trinervis by Frankia

    Directory of Open Access Journals (Sweden)

    Leandro eImanishi

    2014-08-01

    Full Text Available Nitrogen-fixing nodules induced by Frankia in the actinorhizal plant Discaria trinervis result from a primitive intercellular root invasion pathway that does not involve root hair deformation and infection threads. Here, we analyzed the role of auxin in this intercellular infection pathway at the molecular level and compared it with our previous work in the intracellular infected actinorhizal plant Casuarina glauca. Immunolocalisation experiments showed that auxin accumulated in Frankia-infected cells in both systems. We then characterized the expression of auxin transporters in D. trinervis nodules. No activation of the heterologous CgAUX1 promoter was detected in infected cells in D. trinervis. These results were confirmed with the endogenous D. trinervis gene, DtAUX1. However, DtAUX1 was expressed in the nodule meristem. Consistently, transgenic D. trinervis plants containing the auxin response marker DR5:VENUS showed expression of the reporter gene in the meristem. Immunolocalisation experiments using an antibody against the auxin efflux carrier PIN1, revealed the presence of this transporter in the plasma membrane of infected cells. Finally, we used in silico cellular models to analyse auxin fluxes in D. trinervis nodules. Our results point to the existence of divergent roles of auxin in intercellularly- and intracellularly-infected actinorhizal plants, an ancestral infection pathways leading to root nodule symbioses.

  16. Short-range intercellular calcium signaling in bone

    DEFF Research Database (Denmark)

    Jørgensen, Niklas Rye

    2005-01-01

    whether bone cells are capable of communicating via intercellular calcium signals, and determine by which mechanisms the cells propagate the signals. First, we found that osteoblastic cells can propagate intercellular calcium transients upon mechanical stimulation, and that there are two principally...... to osteoclasts as well. We demonstrated that paracrine action of ATP was responsible for the wave propagation, but now the purinergic P2X7 receptor was involved. Thus, the studies demonstrate that calcium signals can be propagated not only among osteoblasts, but also between osteoblasts and osteoclasts...... in response to mechanical stimulation. Thus, intercellular calcium signaling can be a mechanism by which mechanical stimuli on bone are translated into biological signals in bone cells, and propagated through the network of cells in bone. Further, the observations offer new pharmacological targets...

  17. Changes of gap junctional intercellular communication in detrusor instability

    Institute of Scientific and Technical Information of China (English)

    周逢海; 宋波; 金锡御; 范立新

    2004-01-01

    Objective: To demonstrate the functional changes of gap junctional mediation of intercellular communication in detrusor instability (DI) and its mechanisms. Methods: The function of gap junctional intercellular communication in the cultured bladder detrusor cells was detected by fluorescence redistribution after photobleaching. Results: At the fourth minute after bleaching, the mean fluorescences recovery rates of DI group bladder detrusor cells were (35.791±0.836)%, that of control group (8.645±0.673)%. The mean fluorescence recovery rates of DI group were significantly higher than those of control group (P<0.01). Conclusion: It shows that the increase of intercellular excitatory communication is one of the important reasons of pathogenesis of DI.

  18. Modelling intercellular communication and its effects on tumour invasion

    International Nuclear Information System (INIS)

    We present a model aiming at the description of intercellular communication on the invasive character of gliomas. We start from a previous model of ours based on a cellular automaton and develop a new version of it in a three-dimensional geometry. Introducing the hydrodynamic limit of the automaton we obtain a macroscopic model involving a nonlinear diffusion equation. We show that this macroscopic model is quite adequate for the description of realistic situations. Comparison of the simulations with experimental results shows agreement with the finding that the inhibition of intercellular communication (through gap junctions) tends to decrease migration. As an application of our model we estimated the possible increase in life expectancy, due to reduced cell migration mediated by the inhibition of intercellular communication, on patients suffering from gliomas. We find that the obtained increase may amount to a 20% gain in the case of unresectable tumours

  19. Investigation of intercellular salicylic acid accumulation during compatible and incompatible Arabidopsis-pseudomonas syringae interactions using a fast neutron-generated mutant allele of EDS5 identified by genetic mapping and whole-genome sequencing.

    Directory of Open Access Journals (Sweden)

    Jessie L Carviel

    Full Text Available A whole-genome sequencing technique developed to identify fast neutron-induced deletion mutations revealed that iap1-1 is a new allele of EDS5 (eds5-5. RPS2-AvrRpt2-initiated effector-triggered immunity (ETI was compromised in iap1-1/eds5-5 with respect to in planta bacterial levels and the hypersensitive response, while intra- and intercellular free salicylic acid (SA accumulation was greatly reduced, suggesting that SA contributes as both an intracellular signaling molecule and an antimicrobial agent in the intercellular space during ETI. During the compatible interaction between wild-type Col-0 and virulent Pseudomonas syringae pv. tomato (Pst, little intercellular free SA accumulated, which led to the hypothesis that Pst suppresses intercellular SA accumulation. When Col-0 was inoculated with a coronatine-deficient strain of Pst, high levels of intercellular SA accumulation were observed, suggesting that Pst suppresses intercellular SA accumulation using its phytotoxin coronatine. This work suggests that accumulation of SA in the intercellular space is an important component of basal/PAMP-triggered immunity as well as ETI to pathogens that colonize the intercellular space.

  20. Intercellular transfer of apoptotic signals via electrofusion

    International Nuclear Information System (INIS)

    We determined whether cells that are induced to undergo anoikis by matrix detachment can initiate apoptosis in healthy cells following electroporation-induced fusion. Separate populations of MDCK cells undergoing anoikis and stained with FITC-annexin or viable MDCK cells that were labeled with spectrally discrete fluorescent beads were electroporated. Cells were analyzed by flow cytometry for enumeration of viable cells with beads, apoptotic cells or fused cells. Electroporation promoted a 49-fold increase of the percentage of viable cells that had fused with apoptotic cells. Apoptotic cell-viable cell fusions were 8-fold more likely to not attach to cell culture plastic and 2.3-fold less likely to proliferate after 24 hr incubation than viable cell fusion controls. These data demonstrate that apoptotic signals can be transferred between cells by electrofusion, possibly suggesting a novel investigative approach for optimizing targeted cell deletion in cancer treatment.

  1. Intercellular transfer of apoptotic signals via electrofusion

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jin Suk; Lee, Wilson; McCulloch, Christopher A., E-mail: christopher.mcculloch@utoronto.ca

    2012-05-01

    We determined whether cells that are induced to undergo anoikis by matrix detachment can initiate apoptosis in healthy cells following electroporation-induced fusion. Separate populations of MDCK cells undergoing anoikis and stained with FITC-annexin or viable MDCK cells that were labeled with spectrally discrete fluorescent beads were electroporated. Cells were analyzed by flow cytometry for enumeration of viable cells with beads, apoptotic cells or fused cells. Electroporation promoted a 49-fold increase of the percentage of viable cells that had fused with apoptotic cells. Apoptotic cell-viable cell fusions were 8-fold more likely to not attach to cell culture plastic and 2.3-fold less likely to proliferate after 24 hr incubation than viable cell fusion controls. These data demonstrate that apoptotic signals can be transferred between cells by electrofusion, possibly suggesting a novel investigative approach for optimizing targeted cell deletion in cancer treatment.

  2. Interindividual variation in binding of benzo[a]pyrene to DNA in cultured human Bronchi

    DEFF Research Database (Denmark)

    Harris, C.C.; Autrup, Herman; Connor, R.;

    1976-01-01

    The binding of benzo[a]pyrene to DNA in cultured human bronchus was measured in specimens from 37 patients. The binding values ranged from 2 to 151 picomoles of benzo[a]pyrene per milligram of DNA with an overall mean +/- standard error of 34.2 +/- 5.2. This 75-fold interindividual variation in t...

  3. Simple Fluorimetric Determination of Benzo[a]pyrene in Cigarette Smoke without Preseparation Procedure

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Constant-energy synchronous fluorimetry was used for the identification of benzo[a]pyrene in mixtures with a detection limit of 1.34 nmol/L. The recovery experiments in cigarette smoke samples have also obtained satisfactory results of 99.1-103.5% for benzo[a]pyrene.

  4. Stimulation of human red blood cells leads to Ca2+-mediated intercellular adhesion

    CERN Document Server

    Steffen, Patrick; Nguyen, Duc Bach; Müller, Torsten; Bernhardt, Ingolf; Kaestner, Lars; Wagner, Christian

    2011-01-01

    Red blood cells (RBCs) are a major component of blood clots, which form physiologically as a response to injury or pathologically in thrombosis. The active participation of RBCs in thrombus solidification has been previously proposed but not yet experimentally proven. Holographic optical tweezers and single-cell force spectroscopy were used to study potential cell-cell adhesion between RBCs. Irreversible intercellular adhesion of RBCs could be induced by stimulation with lysophosphatidic acid (LPA), a compound known to be released by activated platelets. We identified Ca2+ as an essential player in the signaling cascade by directly inducing Ca2+ influx using A23187. Elevation of the internal Ca2+ concentration leads to an intercellular adhesion of RBCs similar to that induced by LPA stimulation. Using single-cell force spectroscopy, the adhesion of the RBCs was identified to be approximately 100 pN, a value large enough to be of significance inside a blood clot or in pathological situations like the vasco-occ...

  5. Study on roles of gap junctional intercellular communication in low dose parathyroid hormones-induced bone anabolism in vitro%间隙连接通讯功能对小剂量甲状旁腺激素成骨效应调控的机制

    Institute of Scientific and Technical Information of China (English)

    马兴; 胡蕴玉; 李起鸿; 王全平; 吕荣; 王军; 徐新智; 李晓娟; 王德堂

    2003-01-01

    AIM: To investigate mediating and regulatory effects of osteoblastic gap junctional intercelinlar communication(GJIC) on low-dose parathyroid hormones(PTH) -stimulated bone formation activities in vitro. METHODS: Rat calvarial osteoblasts (ROBs) in cultures were divided into three groups according to the different mode of exposure. Group A: vehicle (sodium acetate, SA) -treated group; Group B: 1 × 10-8 mol/L hPTH(1 -34) intermittent exposure group; Group C: 1 × 10-8 mol/L hPTH(1 - 34) + 1 × 10-7mol/L TPA exposure group. 48 h incubation cycles in three groups were repeated for eignt times. GJIC and mineralized bone nodules formation in three groups were detected using Lucifer Yellow (LY) scrape loading dye transfer (SLDT) and mineralized nodule staining together with nodule index, respectively. RESUITS: At various measuring time points of SA × 6 h in group A, PTH × 6 hin group B, PTH×6h+1 hingroupBandPTH×6h+TPA×1 bin group C, LY( + ) cell numbers were 6. 8 ±2.5, 19.5 ±6.5, 14.0 ± 3.6 and 5.7 ± 2.4, respectively. Diffusion and transfer of LY fluorescent probe was much more noticeably discerned in group B than in group A and C( P < 0.01 ) Mineralized bone nodule indices were 45.2 ± 12.5, 88.0 ± 15.3 and 38. 5 ± 17.9 in group A, B and C respectively. Bone formation activity was much better reveaied in group B than in group A and C ( P < 0. 01 ),whereas no statistically significant difference of bone formation activities were found in group A compared with group C( P =0. 465) . CONCLUSION:Mediations aod regulations of the coordinating signals in ostooblastic network via GJIC essentially contribute to PTH-stimulated bone anabolism. However, disruption of GJIC not only hinders ostooblastic intercellular coordination but also frustrates PTH-induced bone formation activities in vitro. Therefore, GJIC may evidently play important roles in regulations on low-dose PTH-induced bone formation.

  6. Intra- and intercellular mechanisms regulating glucose metabolism in the liver.

    NARCIS (Netherlands)

    E. Casteleijn (Eric)

    1988-01-01

    textabstractThe regulation of glucose metabolism in the liver by intraand intercellular mechanisms was studied. Fructose-1,6-bisphosphatase, an enzyme involved in de novo synthesis of glucose was found to be stimulated by glucagon in isolated parenchym~l liver cells. Glucagon increased the Vmax of f

  7. Induction and inhibition of benzo(a)pyrene metabolism in human epidermal keratinocytes and dermal fibroblasts

    International Nuclear Information System (INIS)

    The effects of different growth conditions and various cytochrome P-450 inducers and inhibitors were examined on the benzo(a)pyrene (BP) metabolism of human skin cells in vitro. First, three different populations of neonatal foreskin fibroblasts were treated with 0.98 μM [G-3H]-BP at 9.6 Ci/mmole for 24 hours and the organic-extractable metabolites in the extracellular, the cytoplasmic, and the nuclear fractions were analyzed by high-pressure liquid chromatography (HPLC). Confluent cultures (contact-inhibited cells), which were nontransformable, metabolized BP to a much greater extent than the transformable populations, randomly-proliferating cultures (cells in logarithmic growth) and synchronized cultures (cells treated in S phase). The major extracellular BP metabolites detected were the 9,10-diol, the 7,8-diol, and the phenols, including all four tetrols observed only in the confluent cells. From this data, the state of confluency (i.e. the model for the in vivo state of skin cells) induced enzymes which catalyze primarily the detoxification pathways leading to the formation of metabolites which are readily excreted whereas cells which are actively dividing or synchronized induced the formation of metabolites from activation pathways that led to transformation. Next, the effects of four inducers (3-methylcholanthrene (3-MCA), phenobarbital (PB), isosafrole, and Arochlor 1254) and an inhibitor (butylated hydroxyanisole (BHA)) on the BP metabolism of human epidermal keratinocytes were evaluated

  8. Exosomes Mediate the Intercellular Communication after Myocardial Infarction

    OpenAIRE

    YUAN, MING-JIE; Maghsoudi, Taneen; Tao WANG

    2016-01-01

    The mechanisms of cardiac repair after myocardial infarction (MI) are complicated and not well-understood currently. It is known that exosomes are released from most cells, recognized as new candidates with important roles in intercellular and tissue-level communication. Cells can package proteins and RNA messages into exosome and secret to recipient cells, which regulate gene expression in recipient cells. The research on exosomes in cardiovascular disease is just emerging. It is well-known ...

  9. Intercellular adhesion molecule-1 expression in the hippocampal CA1 region of hyperlipidemic rats with chronic cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Yingying Cheng; Ying Zhang; Hongmei Song; Jiachun Feng

    2012-01-01

    Chronic cerebral ischemia is a pathological process in many cerebrovascular diseases and it is induced by long-term hyperlipidemia, hypertension and diabetes mellitus. After being fed a high-fat diet for 4 weeks, rats were subjected to permanent occlusion of bilateral common carotid arteries to establish rat models of chronic cerebral ischemia with hyperlipidemia. Intercellular adhesion molecule-1 expression in rat hippocampal CA1 region was determined to better understand the mechanism underlying the effects of hyperlipidemia on chronic cerebral ischemia. Water maze test results showed that the cognitive function of rats with hyperlipidemia or chronic cerebral ischemia, particularly in rats with hyperlipidemia combined with chronic cerebral ischemia, gradually decreased between 1 and 4 months after occlusion of the bilateral common carotid arteries. This correlated with pathological changes in the hippocampal CA1 region as detected by hematoxylin-eosin staining. Immunohistochemical staining showed that intercellular adhesion molecule-1 expression in the hippocampal CA1 region was noticeably increased in rats with hyperlipidemia or chronic cerebral ischemia, in particular in rats with hyperlipidemia combined with chronic cerebral ischemia. These findings suggest that hyperlipidemia aggravates chronic cerebral ischemia-induced neurological damage and cognitive impairment in the rat hippocampal CA1 region, which may be mediated, at least in part, by up-regulated expression of intercellular adhesion molecule-1.

  10. Intercellular redistribution of cAMP underlies selective suppression of cancer cell growth by connexin26.

    Directory of Open Access Journals (Sweden)

    Anjana Chandrasekhar

    Full Text Available Connexins (Cx, which constitute gap junction intercellular channels in vertebrates, have been shown to suppress transformed cell growth and tumorigenesis, but the mechanism(s still remain largely speculative. Here, we define the molecular basis by which Cx26, but less frequently Cx43 or Cx32, selectively confer growth suppression on cancer cells. Functional intercellular coupling is shown to be required, producing partial blocks of the cell cycle due to prolonged activation of several mitogenic kinases. PKA is both necessary and sufficient for the Cx26 induced growth inhibition in low serum and the absence of anchorage. Activation of PKA was not associated with elevated cAMP levels, but appeared to result from a redistribution of cAMP throughout the cell population, eliminating the cell cycle oscillations in cAMP required for efficient cell cycle progression. Cx43 and Cx32 fail to mediate this redistribution as, unlike Cx26, these channels are closed during the G2/M phase of the cell cycle when cAMP levels peak. Comparisons of tumor cell lines indicate that this is a general pattern, with growth suppression by connexins occurring whenever cAMP oscillates with the cell cycle, and the gap junction remain open throughout the cell cycle. Thus, gap junctional coupling, in the absence of any external signals, provides a general means to limit the mitotic rate of cell populations.

  11. CHANGES OF INTERCELLULAR COOPERATION IN PERIPHERAL BLOOD IN TREATED PATIENTS WITH CARDIOLOGIC DISEASES

    Directory of Open Access Journals (Sweden)

    L. N. Korichkina

    2009-01-01

    Full Text Available Aim. To study changes of intercellular cooperation in peripheral blood induced by treatment in patients with arterial hypertension (HT, ischemic heart disease (IHD and chronic heart failure (CHF.Material and methods. 610 patients were involved into the study, including 250 patients with HT of stages I-III (50 untreated patients, 150 patients with IHD and 210 patients with CHF of stages I-III. All patients were treated except 50 hypertensive ones. 80 healthy patients (40 men, 40 women were included into control group. Blood smears of patients were evaluated (Romanovsky's stain. A number of leukocyte, autorosettes and autorosettes with erythrocyte lysis was calculated. The cellular association consisting of a neutrophil, monocyte or eosinocyte with 3 or more erythrocytes skintight to their surface defined as autorosettes. Erythrocytes number and hemoglobin level determined in peripheral blood.Results. Single autorosettes in peripheral blood were observed in patients of control group and in untreated patients with HT. Treated patients with HT, IHD and CHF had increased number of autorossets and autorosettes with erythrocytes lysis. This phenomenon resulted in reduction of erythrocytes number and hemoglobin level in peripheral blood.Conclusion. Treated patients with cardiologic diseases had changes in intercellular cooperation. It should be considered at intensive and long term therapy.

  12. The genotoxic effects of benzo[a]pyrene and methamidophos on black porgy evaluated by comet assay

    Science.gov (United States)

    Liu, Rixian; Hong, Huasheng; Wang, Xinhong; Wang, Kejian; Wang, Chunguang

    2005-12-01

    In this study, two common pollutants (benzo[a]pyrene and methamidophos) in marine environment were tested by comet assay for their inducement of in vivo genotoxic effect to the blood cells of black porgy ( Acanthopagrus schlegeli). The fish was exposed to 2 μg/L of benzo[a]pyrene (BaP) and methamidophos, and their mixture. The assay was performed on whole blood at 2 h, 5 h, 24 h and 96 h exposure intervals. A significant increase in DNA damage was observed in each treatment with the pollutants. Additive effect of BaP and methamidophos was also found in the experiment. However, the decrease ratios of DNA damage for 5 h and 96 h exposure interals compared with 2 h and 24 h exposure ones, respectively, were noticed. This phenomenon may be explained by the function of repairing process via enzyme cytochrome P450 in the animal. Evidence of the genotoxicity of organophosphorus pesticides (OPs) and polynuclear aromatic hydrocarbons (PAHs) on marine fish are discussed in this paper.

  13. The genotoxic effects of benzo[a]pyrene and methamidophos on black porgy evaluated by comet assay

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In this study, two common pollutants (benzo[a]pyrene and methamidophos) in marine environment were tested by comet assay for their inducement of in vivo genotoxic effect to the blood cells of black porgy (Acanthopagrus schlegeli). The fish was exposed to 2 μg/L of benzo[a]pyrene (BaP) and methamidophos, and their mixture. The assay was performed on whole blood at 2 h, 5 h, 24 h and 96 h exposure intervals. A significant increase in DNA damage was observed in each treatment with the pollutants. Additive effect of BaP and methamidophos was also found in the experiment. However, the decrease ratios of DNA damage for 5 h and 96 h exposure interals compared with 2 h and 24 h exposure ones, respectively, were noticed. This phenomenon may be explained by the function of repairing process via enzyme cytochrome P450 in the animal. Evidence of the genotoxicity of organophosphorus pesticides (OPs) and polynuclear aromatic hydrocarbons (PAHs) on marine fish are discussed in this paper.

  14. Benzo[a]pyrene treatment leads to changes in nuclear protein expression and alternative splicing

    Energy Technology Data Exchange (ETDEWEB)

    Yan Chunlan; Wu Wei [Department of Toxicology, Zhejiang University School of Public Health, 388 Yu-Hang-Tang Road, Hangzhou, Zhejiang 310058 (China); Li Haiyan [Department of Toxicology, Zhejiang University School of Public Health, 388 Yu-Hang-Tang Road, Hangzhou, Zhejiang 310058 (China); Huzhou Maternity and Child Care Hospital, Huzhou, Zhejiang 313000 (China); Zhang Guanglin [Department of Toxicology, Zhejiang University School of Public Health, 388 Yu-Hang-Tang Road, Hangzhou, Zhejiang 310058 (China); Duerksen-Hughes, Penelope J. [Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92354 (United States); Zhu Xinqiang, E-mail: zhuxq@zju.edu.cn [Department of Toxicology, Zhejiang University School of Public Health, 388 Yu-Hang-Tang Road, Hangzhou, Zhejiang 310058 (China); Yang Jun, E-mail: gastate@zju.edu.cn [Department of Toxicology, Zhejiang University School of Public Health, 388 Yu-Hang-Tang Road, Hangzhou, Zhejiang 310058 (China); Zhejiang-California International Nanosystems Institute, Hangzhou, Zhejiang 310029 (China)

    2010-04-01

    Benzo[a]pyrene (BaP) is a potent pro-carcinogen generated from the combustion of fossil fuel and cigarette smoke. Previously, using a proteomic approach, we have shown that BaP can induce changes in the expression of many cellular proteins, including transcription regulators. In the present study, using a similar approach, we examined the nuclear protein response to BaP in HeLa cells and found that BaP treatment caused expression changes in many nuclear proteins. Twenty-four of these proteins were successfully identified, several of which are involved in the alternative splicing of mRNA, DNA replication, recombination, and repair. The changed expression levels were further confirmed by immunoblot analysis using specific antibodies for two proteins, Lamin A and mitotic checkpoint protein Bub3. The nuclear localization of these two proteins was also confirmed by confocal microscopy. To determine whether alternative splicing was activated following BaP treatment, we examined Fas and CD44, two genes previously shown to be targets of alternative splicing in respond to DNA damage. While no significant activation of alternative splicing was observed for Fas, CD44 splicing variants were found after BaP treatment. Together, these data show that DNA damage induces dramatic changes in nuclear protein expression, and that alternative splicing might be involved in the cellular response to DNA damage.

  15. Morphological transformation and effect on gap junction intercellular communication in Syrian hamster embryo cells as screening tests for carcinogens devoid of mutagenic activity.

    Science.gov (United States)

    Rivedal, E; Mikalsen, S O; Sanner, T

    2000-04-01

    A large fraction of chemicals observed to cause cancer in experimental animals is devoid of mutagenic activity. It is therefore of importance to develop methods that can be used to detect and study environmental carcinogenic agents that do not interact directly with DNA. Previous studies have indicated that induction of in vitro cell transformation and inhibition of gap junction intercellular communication are endpoints that could be useful for the detection of non-genotoxic carcinogens. In the present work, 13 compounds [chlordane, Arochlor 1260, di(2-ethylhexyl)phthalate, 1,1,1-trichloro-2, 2-bis(4-chlorophenyl)ethane, limonene, sodium fluoride, ethionine, o-anisidine, benzoyl peroxide, o-vanadate, phenobarbital, 12-O-tetradecanoylphorbol 13-acetate and clofibrate] have been tested for their ability to induce morphological transformation and affect intercellular communication in Syrian hamster embryo cells. The substances were selected on the basis of being proven or suspected non-genotoxic carcinogens, and thus difficult to detect in short-term tests. The data show that nine of the 13 compounds induced morphological transformation, and seven of the 13 inhibited intercellular communication in hamster embryo cells. Taken together, 12 of the 13 substances either induced transformation or caused inhibition of communication. The data suggest that the combined use of morphological transformation and gap junction intercellular communication in Syrian hamster embryo cells may be beneficial when screening for non-genotoxic carcinogens. PMID:10793297

  16. Toxicokinetic of benzo[a]pyrene and fipronil in female green frogs (Pelophylax kl. esculentus)

    International Nuclear Information System (INIS)

    A general consensus that an increased logKow led to an increase in xenobiotic uptake and bioaccumulation is accepted. In this study we compared the toxicokinetics of two chemically different xenobiotics, i.e. benzo[a]pyrene and fipronil in female green frogs. Surprisingly, the uptake rates and the bioconcentration factors (BCF) of the two contaminants were not predicted by their logKow. The uptake rates obtained were of the same order of magnitude for the two contaminants and the BCFs measured for fipronil were about 3-fold higher than those obtained for benzo[a]pyrene. Fipronil appeared to be more recalcitrant than benzo[a]pyrene to detoxification processes leading to the accumulation of sulfone-fipronil especially in the ovaries. This phenomenon may explain reproductive influence of this contaminant described in other studies. Detoxification processes, including metabolism and the excretion of pollutants, are of importance when considering their persistence in aquatic organisms and trying to quantify their risks. Highlights: ► The uptake of benzo[a]pyrene is 1.5–3 times higher than for fipronil. ► Fipronil was more recalcitrant than benzo[a]pyrene to detoxification processes. ► This lead to increased-bioaccumulation factors except in excretion organs. ► Amphibians can be used as biomonitors for persistent pollutants. - Fipronil is more recalcitrant than benzo[a]pyrene to detoxification processes in frog.

  17. Destruction of the hepatocyte junction by intercellular invasion of Leptospira causes jaundice in a hamster model of Weil's disease.

    Science.gov (United States)

    Miyahara, Satoshi; Saito, Mitsumasa; Kanemaru, Takaaki; Villanueva, Sharon Y A M; Gloriani, Nina G; Yoshida, Shin-ichi

    2014-08-01

    Weil's disease, the most severe form of leptospirosis, is characterized by jaundice, haemorrhage and renal failure. The mechanisms of jaundice caused by pathogenic Leptospira remain unclear. We therefore aimed to elucidate the mechanisms by integrating histopathological changes with serum biochemical abnormalities during the development of jaundice in a hamster model of Weil's disease. In this work, we obtained three-dimensional images of infected hamster livers using scanning electron microscope together with freeze-cracking and cross-cutting methods for sample preparation. The images displayed the corkscrew-shaped bacteria, which infiltrated the Disse's space, migrated between hepatocytes, detached the intercellular junctions and disrupted the bile canaliculi. Destruction of bile canaliculi coincided with the elevation of conjugated bilirubin, aspartate transaminase and alkaline phosphatase levels in serum, whereas serum alanine transaminase and γ-glutamyl transpeptidase levels increased slightly, but not significantly. We also found in ex vivo experiments that pathogenic, but not non-pathogenic leptospires, tend to adhere to the perijunctional region of hepatocyte couplets isolated from hamsters and initiate invasion of the intercellular junction within 1 h after co-incubation. Our results suggest that pathogenic leptospires invade the intercellular junctions of host hepatocytes, and this invasion contributes in the disruption of the junction. Subsequently, bile leaks from bile canaliculi and jaundice occurs immediately. Our findings revealed not only a novel pathogenicity of leptospires, but also a novel mechanism of jaundice induced by bacterial infection. PMID:24945433

  18. Laminin-332 alters connexin profile, dye coupling and intercellular Ca2+ waves in ciliated tracheal epithelial cells

    Science.gov (United States)

    Isakson, Brant E; Olsen, Colin E; Boitano, Scott

    2006-01-01

    Background Tracheal epithelial cells are anchored to a dynamic basement membrane that contains a variety of extracellular matrix proteins including collagens and laminins. During development, wound repair and disease of the airway epithelium, significant changes in extracellular matrix proteins may directly affect cell migration, differentiation and events mediated by intercellular communication. We hypothesized that alterations in cell matrix, specifically type I collagen and laminin α3β3γ2 (LM-332) proteins within the matrix, directly affect intercellular communication in ciliated rabbit tracheal epithelial cells (RTEC). Methods Functional coupling of RTEC was monitored by microinjection of the negatively charged fluorescent dyes, Lucifer Yellow and Alexa 350, into ciliated RTEC grown on either a LM-332/collagen or collagen matrix. Coupling of physiologically significant molecules was evaluated by the mechanism and extent of propagated intercellular Ca2+ waves. Expression of connexin (Cx) mRNA and proteins were assayed by reverse transcriptase – polymerase chain reaction and immunocytochemistry, respectively. Results When compared to RTEC grown on collagen alone, RTEC grown on LM-332/collagen displayed a significant increase in dye transfer. Although mechanical stimulation of RTEC grown on either LM-332/collagen or collagen alone resulted in intercellular Ca2+ waves, the mechanism of transfer was dependent on matrix: RTEC grown on LM-332/collagen propagated Ca2+waves via extracellular purinergic signaling whereas RTEC grown on collagen used gap junctions. Comparison of RTEC grown on collagen or LM-332/collagen matrices revealed a reorganization of Cx26, Cx43 and Cx46 proteins. Conclusion Alterations in airway basement membrane proteins such as LM-332 can induce connexin reorganizations and result in altered cellular communication mechanisms that could contribute to airway tissue function. PMID:16884540

  19. Signaling through intercellular adhesion molecule 1 (ICAM-1) in a B cell lymphoma line

    DEFF Research Database (Denmark)

    Holland, J; Owens, T

    1997-01-01

    Intercellular adhesion molecule 1 (ICAM-1) (CD54) is an adhesion molecule of the immunoglobulin superfamily. The interaction between ICAM-1 on B lymphocytes and leukocyte function-associated antigen 1 on T cells plays a major role in several aspects of the immune response, including T-dependent B...... cell activation. While it was originally believed that ICAM-1 played a purely adhesive role, recent evidence suggests that it can itself transduce biochemical signals. We demonstrate that cross-linking of ICAM-1 results in the up-regulation of class II major histocompatibility complex, and we...... investigate the biochemical mechanism for the signaling role of ICAM-1. We show that cross-linking of ICAM-1 on the B lymphoma line A20 induces an increase in tyrosine phosphorylation of several cellular proteins, including the Src family kinase p53/p56(lyn). In vitro kinase assays showed that Lyn kinase...

  20. Effects of extremely low frequency magnetic fields on gap junctional intercellular communication and its mechanism

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The study on biological effect of electromagnetic fields has been paid close attention in recent years. Gap junctional intercellular communication (GJIC) plays an important role in the maintenance of cell proliferation and differentiation, and in the multistage process of carcinogenesis. A series of researches showed that xtremely low frequency (ELF) magnetic fields not only enhance the inhibition of GJIC induced by 12-O-tetradecanoylphorbol-13-acetate, but also inhibit GJIC directly when the intensity is equal to or more than 0.4  mT, and that the mechanisms of GJIC inhibition by ELF magnetic fields are due to hyperphosphorylation of connexin 43, which is mediated by protein kinase C-activated signal transduction, and the internalization of connexin 43 from plasma membrane to cytoplasm.

  1. Intercellular salicylic acid accumulation during compatible and incompatible Arabidopsis-Pseudomonas syringae interactions.

    Science.gov (United States)

    Wilson, Daniel C; Carella, Philip; Cameron, Robin K

    2014-01-01

    The phytohormone salicylic acid (SA) plays an important role in several disease resistance responses. During the Age-Related Resistance (ARR) response that occurs in mature Arabidopsis responding to Pseudomonas syringae pv tomato (Pst), SA accumulates in the intercellular space where it may act as an antimicrobial agent. Recently we measured intracellular and intercellular SA levels in young, ARR-incompetent plants responding to virulent and avirulent strains of Pst to determine if intercellular SA accumulation is a component of additional defense responses to Pst. In young plants virulent Pst suppressed both intra- and intercellular SA accumulation in a coronatine-dependent manner. In contrast, high levels of intra- and intercellular SA accumulated in response to avirulent Pst. Our results support the idea that SA accumulation in the intercellular space is an important component of multiple defense responses. Future research will include understanding how mature plants counteract the effects of coronatine during the ARR response.

  2. Effects of benzo(a)pyrene exposure on the antioxidant enzyme activity of scallop Chlamys farreri

    Science.gov (United States)

    Pan, Luqing; Ren, Jiayun; Zheng, Debin

    2009-02-01

    Scallop Chlamys farreri was exposed to different concentrations of benzo(a)pyrene (BaP) (0.5 μg/L, 1.0 μg/L, 10.0 μg/L and 50.0 μg/L) for 30 days in seawater. The 7-ethoxyresorufin O-deethylase (EROD) activity was significantly induced, and increased with the increasing BaP concentration. The glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), Glutathione peroxidase (GPx) activities increased in short time at low concentration of BaP, and was significantly depressed at high concentrations. Scallop gill was more sensitive to BaP than the digestive gland, and the digestive gland was the main tissue to deal with oxyradicals. The contents of malondialdehyde (MDA) increased with the exposure time and there was a positive correlation (concentration-effect) between the MDA content and the concentration of BaP. The biomarkers determined in this experiment had important roles in detoxification, and showed great potential as biomarkers for oxidative stress. Controlled laboratory experiments designed to simulate field exposure scenarios are particularly useful in ascertaining biomarkers suitable for use with complex contaminant mixtures in the marine environment.

  3. Effects of benzo(a)pyrene exposure on the antioxidant enzyme activity of scallop Chlamys farreri

    Institute of Scientific and Technical Information of China (English)

    PAN Luqing; REN Jiayun; ZHENG Debin

    2009-01-01

    Scallop Chlamys farreri was exposed to different concentrations of benzo(a)pyrene (BaP) (0.5 μg/L, 1.0 μg/L, 10.0 μg/L and 50.0 μg/L) for 30 days in seawater. The 7-ethoxyresorufin O-deethylase (EROD) activity was significantly induced, and increased with the increasing BaP concentration. The glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), Glutathione peroxidase (GPx) activities increased in short time at low concentration of BaP, and was significantly depressed at high concentrations. Scallop gill was more sensitive to BaP than the digestive gland, and the digestive gland was the main tissue to deal with oxyradicals. The contents of malondialdehyde (MDA) increased with the exposure time and there was a positive correlation (concentration-effect) between the MDA content and the concentration of BaP. The biomarkers determined in this experiment had important roles in detoxification, and showed great potential as biomarkers for oxidative stress. Controlled laboratory experiments designed to simulate field exposure scenarios are particularly useful in ascertaining biomarkers suitable for use with complex contaminant mixtures in the marine environment.

  4. Intercellular Communication in Malignant Pleural Mesothelioma: Properties of Tunneling Nanotubes

    Directory of Open Access Journals (Sweden)

    Justin William Ady

    2014-10-01

    Full Text Available Malignant pleural mesothelioma is a particularly aggressive and locally invasive malignancy with a poor prognosis despite advances in understanding of cancer cell biology and development of new therapies. At the cellular level, cultured mesothelioma cells present a mesenchymal appearance and a strong capacity for local cellular invasion. One important but underexplored area of mesothelioma cell biology is intercellular communication. Our group has previously characterized in multiple histological subtypes of mesothelioma a unique cellular protrusion known as tunneling nanotubes (TnTs. TnTs are long, actin filament-based, narrow cytoplasmic extensions that are non-adherent when cultured in vitro and are capable of shuttling cellular cargo between connected cells. Our prior work confirmed the presence of nanotube structures in tumors resected from patients with human mesothelioma. In our current study, we quantified the number of TnTs/cell among various mesothelioma subtypes and normal mesothelial cells using confocal microscopic techniques. We also examined TnT length among adherent cells and cells in suspension. We further examined potential approaches to the in vivo study of TnTs in animal models of cancer. We have developed novel approaches to study TnTs in aggressive solid tumor malignancies and define fundamental characteristics of TnTs in malignant mesothelioma. There is mounting evidence that TnTs play an important role in intercellular communication in mesothelioma and thus merit further investigation of their role in vivo.

  5. Identification and characterization of RBM44 as a novel intercellular bridge protein.

    Directory of Open Access Journals (Sweden)

    Tokuko Iwamori

    Full Text Available Intercellular bridges are evolutionarily conserved structures that connect differentiating germ cells. We previously reported the identification of TEX14 as the first essential intercellular bridge protein, the demonstration that intercellular bridges are required for male fertility, and the finding that intercellular bridges utilize components of the cytokinesis machinery to form. Herein, we report the identification of RNA binding motif protein 44 (RBM44 as a novel germ cell intercellular bridge protein. RBM44 was identified by proteomic analysis after intercellular bridge enrichment using TEX14 as a marker protein. RBM44 is highly conserved between mouse and human and contains an RNA recognition motif of unknown function. RBM44 mRNA is enriched in testis, and immunofluorescence confirms that RBM44 is an intercellular bridge component. However, RBM44 only partially localizes to TEX14-positive intercellular bridges. RBM44 is expressed most highly in pachytene and secondary spermatocytes, but disappears abruptly in spermatids. We discovered that RBM44 interacts with itself and TEX14 using yeast two-hybrid, mammalian two-hybrid, and immunoprecipitation. To define the in vivo function of RBM44, we generated a targeted deletion of Rbm44 in mice. Rbm44 null male mice produce somewhat increased sperm, and show enhanced fertility of unknown etiology. Thus, although RBM44 localizes to intercellular bridges during meiosis, RBM44 is not required for fertility in contrast to TEX14.

  6. Linking embryo toxicity with genotoxic responses in the freshwater snail Physa acuta: single exposure to benzo(a)pyrene, fluoxetine, bisphenol A, vinclozolin and exposure to binary mixtures with benzo(a)pyrene.

    Science.gov (United States)

    Sánchez-Argüello, Paloma; Aparicio, Natalia; Fernández, Carlos

    2012-06-01

    Genotoxic effects on fauna after waterborne pollutant exposure have been demonstrated by numerous research programmes. Less effort has been focused on establishing relationship between genotoxicity and long-term responses at higher levels of biological organization. Taking into account that embryos may be more sensitive indicators of reproductive impairment than alterations in fertility, we have developed two assays in multiwell plates to address correlations between embryo toxicity and genotoxicity. The potential teratogenicity was assessed by analyzing abnormal development and mortality of Physa acuta at embryonic stage. Genotoxicity was measured by the micronucleus (MN) test using embryonic cells. Our results showed that linkage between genotoxicity and embryo toxicity depends on mechanisms of action of compounds under study. Embryo toxic responses showed a clear dose-related tendency whereas no clear dose-dependent effect was observed in micronucleus induction. The higher embryo toxicity was produced by benzo(a)pyrene exposure followed by fluoxetine and bisphenol A. Vinclozolin was the lower embryo toxic compound. Binary mixtures with BaP always resulted in higher embryo toxicity than single exposures but antagonistic effects were observed for MN induction. Benzo(a)pyrene produced the higher MN induction at 0.04 mg/L, which also produced clear embryo toxic effects. Fluoxetine did not induce cytogenetic effects but 0.25mg/L altered embryonic development. Bisphenol A significantly reduced hatchability at 0.5mg/L while MN induction appeared with higher treatments than those that start causing teratogenicity. Much higher concentration of vinclozolin (5mg/L) reduced hatchability and induced maximum MN formation. In conclusion, while validating one biomarker of genotoxicity and employing one ecologically relevant effect, we have evaluated the relative sensitivity of a freshwater mollusc for a range of chemicals. The embryo toxicity test is a starting point for the

  7. [Benzo(a)pyrene contamination of vegetable oils].

    Science.gov (United States)

    Jedra, Małgorzata; Starski, Andrzej; Gawarska, Halina; Sawilska-Rautenstrauch, Dorota

    2008-01-01

    Benzo(a)pyrene (B(a)P) analysis was carried out with glass chromatographic column with alumina followed by reverse phase high-performance liquid chromatography (HPLC) and spectrofluorometric detection. B(a)P level in 40 vegetable oils were as follow: from 0.11 to 0.38 microg/kg in olive; from 0.92 to 3.74 microg/kg in rape seed oils; from 0.11 to 2.25 microg/kg in sunflower oils and from 0.33 to 1.26 microg/kg in soya oils. In another investigated oils: arachide (peanut) corn, safflower, linen, hempen, sesame, pumpkin seeds, grape seeds---values from 0.10 to 1.44 microg/kg and 3.83 microg/kg in sea buckthorn oil were detected. B(a)P concentration in 4 from 40 investigated oils exceed the 2 ppb limit proposed by the European Commission. Heating of sample of oils: olive, rape, soya, linen, corn, sesame, peanut, in temp. 240 degrees C for 30 min. has not influence on decreased of B(a)P level. PMID:18807910

  8. Proteomic analysis of exosomes from nasopharyngeal carcinoma cell identifies intercellular transfer of angiogenic proteins.

    Science.gov (United States)

    Chan, Yuk-Kit; Zhang, Huoming; Liu, Pei; Tsao, Sai-Wah; Lung, Maria Li; Mak, Nai-Ki; Ngok-Shun Wong, Ricky; Ying-Kit Yue, Patrick

    2015-10-15

    Exosomes, a group of secreted extracellular nanovesicles containing genetic materials and signaling molecules, play a critical role in intercellular communication. During tumorigenesis, exosomes have been demonstrated to promote tumor angiogenesis and metastasis while their biological functions in nasopharyngeal carcinoma (NPC) are poorly understood. In this study, we focused on the role of NPC-derived exosomes on angiogenesis. Exosomes derived from the NPC C666-1 cells and immortalized nasopharyngeal epithelial cells (NP69 and NP460) were isolated using ultracentrifugation. The molecular profile and biophysical characteristics of exosomes were verified by Western blotting, sucrose density gradient and electron microscopy. We showed that the C666-1 exosomes (10 and 20 μg/ml) could significantly increase the tubulogenesis, migration and invasion of human umbilical vein endothelial cells (HUVECs) in a dose-dependent manner. Subsequently, an iTRAQ-based quantitative proteomics was used to identify the differentially expressed proteins in C666-1 exosomes. Among the 640 identified proteins, 51 and 89 proteins were considered as up- and down-regulated (≥ 1.5-fold variations) in C666-1 exosomes compared to the normal counterparts, respectively. As expected, pro-angiogenic proteins including intercellular adhesion molecule-1 (ICAM-1) and CD44 variant isoform 5 (CD44v5) are among the up-regulated proteins, whereas angio-suppressive protein, thrombospondin-1 (TSP-1) was down-regulated in C666-1 exosomes. Further confocal microscopic study and Western blotting clearly demonstrated that the alteration of ICAM-1 and TSP-1 expressions in recipient HUVECs are due to internalization of exosomes. Taken together, these data strongly indicated the critical roles of identified angiogenic proteins in the involvement of exosomes-induced angiogenesis, which could potentially be developed as therapeutic targets in future.

  9. Proteomic analysis of exosomes from nasopharyngeal carcinoma cell identifies intercellular transfer of angiogenic proteins

    KAUST Repository

    Chan, Yuk-kit

    2015-04-01

    Exosomes, a group of secreted extracellular nanovesicles containing genetic materials and signaling molecules, play a critical role in intercellular communication. During tumorigenesis, exosomes have been demonstrated to promote tumor angiogenesis and metastasis while their biological functions in nasopharyngeal carcinoma (NPC) are poorly understood. In this study, we focused on the role of NPC-derived exosomes on angiogenesis. Exosomes derived from the NPC C666-1 cells and immortalized nasopharyngeal epithelial cells (NP69 and NP460) were isolated using ultracentrifugation. The molecular profile and biophysical characteristics of exosomes were verified by Western blotting, sucrose density gradient, and electron microscopy. We showed that the C666-1 exosomes (10 and 20 μg/ml) could significantly increase the tubulogenesis, migration and invasion of human umbilical vein endothelial cells (HUVECs) in a dose-dependent manner. Subsequently, an iTRAQ-based quantitative proteomics was used to identify the differentially expressed proteins in C666-1 exosomes. Among the 640 identified proteins, 51 and 89 proteins were considered as up- and down-regulated (≥ 1.5-fold variations) in C666-1 exosomes compared to the normal counterparts, respectively. As expected, pro-angiogenic proteins including intercellular adhesion molecule-1 (ICAM-1) and CD44 variant isoform 5 (CD44v5) are among the up-regulated proteins, whereas angio-suppressive protein, thrombospondin-1 (TSP-1) was down-regulated in C666-1 exosomes. Further confocal microscopic study and Western blotting clearly demonstrated that the alteration of ICAM-1, and TSP-1 expressions in recipient HUVECs are due to internalization of exosomes. Taken together, these data strongly indicated the critical roles of identified angiogenic proteins in the involvement of exosomes-induced angiogenesis, which could potentially be developed as therapeutic targets in future. This article is protected by copyright. All rights reserved.

  10. Intercellular communication, NO and the biology of Chinese medicine

    Directory of Open Access Journals (Sweden)

    Ralt Dina

    2005-05-01

    Full Text Available Abstract New multiple categories of health disciplines have become popular in the west and integration between the medicinal approaches has become essential. The hypothesis presented here suggests a novel integrative view that combines Western biochemistry with the Chinese medicinal concept of qi. The core for this hypothesis is that transmission of qi along the meridians is based on informational molecules that travel via an intercellular communication system. Acupuncture at specific points enhances the flow of the signaling molecules through this communication system. Nitric oxide is suggested as a prime candidate for such a signaling molecule in the meridian system. The biochemistry of nitric oxide can shed light on the biology underlying Chinese medicine while Chinese medicinal data can provide a clue to the sought after framework for nitric oxide.

  11. Role of mitochondria and network connectivity in intercellular calcium oscillations

    CERN Document Server

    Dokukina, I V; Grachev, E A; Gunton, J D; Dokukina, Irina V.; Gracheva, Maria E.; Grachev, Eugene A.; Gunton, James D.

    2005-01-01

    Mitochondria are large-scale regulators of cytosolic calcium under normal cellular conditions. In this paper we model the complex behavior of mitochondrial calcium during the action of inositol 1,4,5-trisphosphate on a single cell and find results that are in good agreement with recent experimental studies. We also study the influence of the cellular network connectivity on intercellular signalling via gap junction diffusion. We include in our model the dependence of the junctional conductivity on the cytosolic calcium concentrations in adjacent cells. We consider three different mechanisms of calcium wave propagation through gap junctions: via calcium diffusion, inositol 1,4,5-trisphosphate diffusion, and both calcium and inositol 1,4,5-trisphosphate diffusion. We show that inositol 1,4,5-trisphosphate diffusion is the mechanism of calcium wave propagation and that calcium diffusion is the mechanism of synchronization of cytosolic calcium oscillations in adjacent cells. We also study the role of different to...

  12. Extracellular vesicles: masters of intercellular communication and potential clinical interventions.

    Science.gov (United States)

    Pitt, Jonathan M; Kroemer, Guido; Zitvogel, Laurence

    2016-04-01

    Intercellular signaling via extracellular vesicles (EVs) is an underappreciated modality of cell-cell crosstalk that enables cells to convey packages of complex instructions to specific recipient cells. EVs transmit these instructions through their cargoes of multiple proteins, nucleic acids, and specialized lipids, which are derived from their cells of origin and allow for combinatorial effects upon recipient cells. This Review series brings together the recent progress in our understanding of EV signaling in physiological and pathophysiological conditions, highlighting how certain EVs, particularly exosomes, can promote or regulate infections, host immune responses, development, and various diseases - notably cancer. Given the diverse nature of EVs and their abilities to profoundly modulate host cells, this series puts particular emphasis on the clinical applications of EVs as therapeutics and as diagnostic biomarkers.

  13. Loss of VHL in RCC reduces repair and alters cellular response to benzo[a]pyrene

    Directory of Open Access Journals (Sweden)

    Marten eSchults

    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.

  14. Miro1 regulates intercellular mitochondrial transport & enhances mesenchymal stem cell rescue efficacy.

    Science.gov (United States)

    Ahmad, Tanveer; Mukherjee, Shravani; Pattnaik, Bijay; Kumar, Manish; Singh, Suchita; Kumar, Manish; Rehman, Rakhshinda; Tiwari, Brijendra K; Jha, Kumar A; Barhanpurkar, Amruta P; Wani, Mohan R; Roy, Soumya S; Mabalirajan, Ulaganathan; Ghosh, Balaram; Agrawal, Anurag

    2014-05-01

    There is emerging evidence that stem cells can rejuvenate damaged cells by mitochondrial transfer. Earlier studies show that epithelial mitochondrial dysfunction is critical in asthma pathogenesis. Here we show for the first time that Miro1, a mitochondrial Rho-GTPase, regulates intercellular mitochondrial movement from mesenchymal stem cells (MSC) to epithelial cells (EC). We demonstrate that overexpression of Miro1 in MSC (MSCmiro(Hi)) leads to enhanced mitochondrial transfer and rescue of epithelial injury, while Miro1 knockdown (MSCmiro(Lo)) leads to loss of efficacy. Treatment with MSCmiro(Hi) was associated with greater therapeutic efficacy, when compared to control MSC, in mouse models of rotenone (Rot) induced airway injury and allergic airway inflammation (AAI). Notably, airway hyperresponsiveness and remodeling were reversed by MSCmiro(Hi) in three separate allergen-induced asthma models. In a human in vitro system, MSCmiro(Hi) reversed mitochondrial dysfunction in bronchial epithelial cells treated with pro-inflammatory supernatant of IL-13-induced macrophages. Anti-inflammatory MSC products like NO, TGF-β, IL-10 and PGE2, were unchanged by Miro1 overexpression, excluding non-specific paracrine effects. In summary, Miro1 overexpression leads to increased stem cell repair. PMID:24431222

  15. Increasing the endogenous NO level causes catalase inactivation and reactivation of intercellular apoptosis signaling specifically in tumor cells.

    Science.gov (United States)

    Bauer, Georg

    2015-12-01

    Tumor cells generate extracellular superoxide anions and are protected against intercellular apoptosis-inducing HOCl- and NO/peroxynitrite signaling through the expression of membrane-associated catalase. This enzyme decomposes H2O2 and thus prevents HOCl synthesis. It efficiently interferes with NO/peroxynitrite signaling through oxidation of NO and decomposition of peroxynitrite. The regulatory potential of catalase at the crosspoint of ROS and RNS chemical biology, as well as its high local concentration on the outside of the cell membrane of tumor cells, establish tight control of intercellular signaling and thus prevent tumor cell apoptosis. Therefore, inhibition of catalase or its inactivation by singlet oxygen reactivate intercellular apoptosis-inducing signaling. Nitric oxide and peroxynitrite are connected with catalase in multiple and meaningful ways, as (i) NO can be oxidated by compound I of catalase, (ii) NO can reversibly inhibit catalase, (iii) peroxynitrite can be decomposed by catalase and (iv) the interaction between peroxynitrite and H2O2 leads to the generation of singlet oxygen that inactivates catalase. Therefore, modulation of the concentration of free NO through addition of arginine, inhibition of arginase, induction of NOS expression or inhibition of NO dioxygenase triggers an autoamplificatory biochemical cascade that is based on initial formation of singlet oxygen, amplification of superoxide anion/H2O2 and NO generation through singlet oxygen dependent stimulation of the FAS receptor and caspase-8. Finally, singlet oxygen is generated at sufficiently high concentration to inactivate protective catalase and to reactivate intercellular apoptosis-inducing ROS signaling. This regulatory network allows to establish several pathways for synergistic interactions, like the combination of modulators of NO metabolism with enhancers of superoxide anion generation, modulators of NO metabolism that act at different targets and between modulators of

  16. Preferential Formation of Benzo[a]pyrene Adducts at Lung Cancer Mutational Hotspots in P53

    Science.gov (United States)

    Denissenko, Mikhail F.; Pao, Annie; Tang, Moon-Shong; Pfeifer, Gerd P.

    1996-10-01

    Cigarette smoke carcinogens such as benzo[a]pyrene are implicated in the development of lung cancer. The distribution of benzo[a]pyrene diol epoxide (BPDE) adducts along exons of the P53 gene in BPDE-treated HeLa cells and bronchial epithelial cells was mapped at nucleotide resolution. Strong and selective adduct formation occurred at guanine positions in codons 157, 248, and 273. These same positions are the major mutational hotspots in human lung cancers. Thus, targeted adduct formation rather than phenotypic selection appears to shape the P53 mutational spectrum in lung cancer. These results provide a direct etiological link between a defined chemical carcinogen and human cancer.

  17. Pannexin 1 channels play essential roles in urothelial mechanotransduction and intercellular signaling.

    Directory of Open Access Journals (Sweden)

    Hiromitsu Negoro

    Full Text Available Urothelial cells respond to bladder distension with ATP release, and ATP signaling within the bladder and from the bladder to the CNS is essential for proper bladder function. In other cell types, pannexin 1 (Panx1 channels provide a pathway for mechanically-induced ATP efflux and for ATP-induced ATP release through interaction with P2X7 receptors (P2X7Rs. We report that Panx1 and P2X7R are functionally expressed in the bladder mucosa and in immortalized human urothelial cells (TRT-HU1, and participate in urothelial ATP release and signaling. ATP release from isolated rat bladders induced by distention was reduced by the Panx1 channel blocker mefloquine (MFQ and was blunted in mice lacking Panx1 or P2X7R expression. Hypoosmotic shock induced YoPro dye uptake was inhibited by MFQ and the P2X7R blocker A438079 in TRT-HU1 cells, and was also blunted in primary urothelial cells derived from mice lacking Panx1 or P2X7R expression. Rinsing-induced mechanical stimulation of TRT-HU1 cells triggered ATP release, which was reduced by MFQ and potentiated in low divalent cation solution (LDPBS, a condition known to enhance P2X7R activation. ATP signaling evaluated as intercellular Ca2+ wave radius was significantly larger in LDPBS, reduced by MFQ and by apyrase (ATP scavenger. These findings indicate that Panx1 participates in urothelial mechanotransduction and signaling by providing a direct pathway for mechanically-induced ATP release and by functionally interacting with P2X7Rs.

  18. Effect of gap junction-mediated intercellular communication on growth differentiation factor 5-induced chondrogenic differentiation in vitro%缝隙连接细胞间通讯在生长分化因子5诱导软骨分化中的作用

    Institute of Scientific and Technical Information of China (English)

    郭珈宜; 崔宏勋; 郭马珑; 郭艳幸; 郭艳锦

    2014-01-01

    Objective To investigate the effect of gap junctional blocker oleamide on growth differentiation factor 5 (GDF-5) induced chondrogenic differentiation.Methods hunan mesenchymal stem cells (hMSCs) were isolated and cultured in vitro,and the cells from Passage 3 were used in this study.hMSCs were randomly grouped into three according to the kinds of induction medium (0,100 μg/L GDF-5,100 μg/L GDF-5 + 2.5 μmol/L oleamide).The proliferation of hMSCs was investigated by methyl thiazol tetrazolium (MTT) assay.The cells were resuspended and the pellets were constructed by centrifugation at a density of 5 × 109/L,and then continued to be kept for two weeks.Reverse transcription-polymerase chain reaction (RT-PCR) was performed to detect the expression of mRNA of type Ⅱ collagen,comexin 43 (Cx43)and aggrecan.Western blotting was performed to detect the expression of protein of type Ⅱ collagen,Cx43and aggrecan.Toluidine blue was performed to detect extracellular matrix staining.Results GDF-5 can promote the mRNA expression of type Ⅱ collagen,Cx43 and aggrecan (1.00 ± 0.03 vs.0.40 ± 0.12 ;1.00 ±0.07 vs.0.32 ±0.02; 1.00 ±0.02 vs.0.45 ±0.01,P <0.01),and the relative protein expression was also increased (1.50±0.11 vs.0.53 ±0.07; 1.70 ±0.14 vs.0.52 ±0.04; 1.00 ±0.12 vs.0.50±0.06,P<0.01).While oleamide could up-regulate the expression of mRNA of Cx43 (0.94 ±0.12 vs.0.45 ±0.01,P <0.01),but had no effect on type Ⅱ collagen and aggrecan mRNA expression.Oleamide could down-regulate the expression of protein of type Ⅱ collagen and aggrecan,but had no effect onCx43 protein expression(0.42 ± 0.04 vs.0.53 ±0.07; 0.38 ±0.06 vs.0.52 ±0.04,P<0.01).Toluidine blue staining showed that GDF-5 can promote the synthesis of aggrecan.Conclusion GDF-5 modulation of chondrogenesis involves gap junction-mediated intercellular communication.%目的 观察缝隙连接细胞间通讯(GJIC)在生长分化因子5(GDF-5)诱导人骨髓间充质干细胞(hMSCs)成

  19. Antiproliferative Action of Conjugated Linoleic Acid on Human MCF-7 Breast Cancer Cells Mediated by Enhancement of Gap Junctional Intercellular Communication through Inactivation of NF-κB

    OpenAIRE

    Rakib, Md. Abdur; Lee, Won Sup; Kim, Gon Sup; Han, Jae Hee; Kim, Jeong Ok; Ha, Yeong Lae

    2013-01-01

    The major conjugated linoleic acid (CLA) isomers, c9,t11-CLA and t10,c12-CLA, have anticancer effects; however, the exact mechanisms underlying these effects are unknown. Evidence suggests that reversal of reduced gap junctional intercellular communication (GJIC) in cancer cells inhibits cell growth and induces cell death. Hence, we determined that CLA isomers enhance GJIC in human MCF-7 breast cancer cells and investigated the underlying molecular mechanisms. The CLA isomers significantly en...

  20. Antiproliferative Action of Conjugated Linoleic Acid on Human MCF-7 Breast Cancer Cells Mediated by Enhancement of Gap Junctional Intercellular Communication through Inactivation of NF- κ B

    OpenAIRE

    Md. Abdur Rakib; Won Sup Lee; Gon Sup Kim; Jae Hee Han; Jeong Ok Kim; Yeong Lae Ha

    2013-01-01

    The major conjugated linoleic acid (CLA) isomers, c9,t11-CLA and t10,c12-CLA, have anticancer effects; however, the exact mechanisms underlying these effects are unknown. Evidence suggests that reversal of reduced gap junctional intercellular communication (GJIC) in cancer cells inhibits cell growth and induces cell death. Hence, we determined that CLA isomers enhance GJIC in human MCF-7 breast cancer cells and investigated the underlying molecular mechanisms. The CLA isomers significantly en...

  1. Synthesis and characterization of electroactive films based on benzo(a)pyrene

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Michal; Yu Kai [Process Chemistry Centre, c/o Laboratory of Analytical Chemistry, Abo Akademi University, Biskopsgatan 8, FI-20500 Abo/Turku (Finland); Kvarnstroem, Carita, E-mail: carita.kvarnstrom@utu.f [Turku University Centre for Materials and Surfaces, c/o Laboratory of Materials Chemistry and Chemical Analysis, Department of Chemistry, University of Turku, Vatselankatu 2, FI-20014 Turku (Finland); Ivaska, Ari, E-mail: ari.ivaska@abo.f [Process Chemistry Centre, c/o Laboratory of Analytical Chemistry, Abo Akademi University, Biskopsgatan 8, FI-20500 Abo/Turku (Finland)

    2011-04-01

    The polycyclic aromatic hydrocarbons (PAHs) are a group of compounds that might have practical applications due to their graphene-like properties. Derivatized PAHs can self-assemble in liquid crystal form. The chemical synthesis of large size PAHs can however be complicated and problematic. Electrochemical synthesis of PAHs molecules was studied in this work by cyclic voltammetry. Benzo(a)pyrene was used as the monomer. The resulting electroactive films consist of different PAHs in both size and symmetry. We call this mixture poly(benzopyrene) (PBP). The synthesis conditions of PBP were optimized to obtain thick and electrochemically stable films. The best film quality was achieved by potential scanning in propylene carbonate at low scan rate resulting in continues polymer growth during 10 scans giving approx. a 1 {mu}m thick PBP film. During p- and n-doping studies the reduction and oxidation peaks were observed at 1.0 V and -1.6 V, respectively, with an electrochemical band gap of approx. 2.6 eV. The in situ UV-vis characterization of the PBP films was made by applying a constant potential with increasing steps. The optical band gap was approx. 2.5 eV and the absorption maximum was observed at ca. 420 nm. During p- and n-doping new induced bands were formed in the range 575-600 nm. UV-vis spectroscopy indicate that PBP mainly consist of units consisting of more than 40 carbon atoms and large number of {pi}-electrons.

  2. Dimethylarsenic acid damages cellular DNA and inhibits gap junctional intercellular communication between human skin fibroblast cells

    Institute of Scientific and Technical Information of China (English)

    GuoXB; DengFR

    2002-01-01

    Although arsenic is identified as a human carcinogen,there is currently no accepted mechanism for its action or an established animal model for evaluating the carcinogenic activity of arsenic.To elucidate the mechanism of arsenic arcinogenesis,we investigated the effect of dimethylarsenic acid(DMAA),the main metabolite of inorganic arsenic in humans,on the cellular DNA and gap junctional intercellular communication (GJIC) between human skin fibroblast cells.Single-cell gel electrophoresis (SCGE) assay was used to detect the DNA damage in human skin fibroblast cells exposed to DMAA,and the GJIC between cells was detected by the scrape loading/dye transfer assay.DMAA at concentrations of 0.01-1.0 mmol·L-1 induced DNA damage in a dose-dependent manner,and GJIC between human skin fibroblast cells was significantly inhibited by DMAA at 1.0 mmol·L-1.Our results suggest that both genotoxic and nongenotoxic mechanism are involved in the mechanism of DMAA-induced cellular toxicity.

  3. Engagement of major histocompatibility complex class I and class II molecules up-regulates intercellular adhesion of human B cells via a CD11/CD18-independent mechanism.

    Science.gov (United States)

    Alcover, A; Juillard, V; Acuto, O

    1992-02-01

    We have studied the role of major histocompatibility complex (MHC) molecules in the regulation of intercellular adhesion of human B cells. We found that molecules able to bind to MHC class II molecules, such as monoclonal antibodies or staphylococcal enterotoxins, induced rapid and sustained homotypic adhesion of Epstein-Barr virus (EBV)-transformed B cell lines as well as peripheral blood B lymphocytes. Moreover, anti-MHC class I monoclonal antibodies also stimulated intercellular adherence. Adhesion induced upon MHC engagement was faster and stronger than that triggered by phorbol esters. It needed active metabolism, but divalent cations were not required. Monoclonal antibodies directed against LFA-1 (CD11a/CD18) or its ligand ICAM-1 (CD54) did not inhibit MHC class II-induced homotypic adhesion of various EBV-transformed B cell lines, nor of a variant of the B cell line Raji expressing very low LFA-1 surface levels. Moreover, EBV-transformed B cells from a severe lymphocyte adhesion deficiency patient, lacking surface CD11/CD18, also aggregated in response to anti-MHC class I or class II monoclonal antibodies. Together these data indicate that engagement of MHC molecules may transduce signals to B cells resulting in up-regulation of intercellular adhesion, via an LFA-1-independent mechanism. This may play a role in the stabilization of T cell/antigen-presenting cell conjugates at the moment of antigen recognition.

  4. Microvesicles and intercellular communication in the context of parasitism

    Directory of Open Access Journals (Sweden)

    Natasha S. Barteneva

    2013-09-01

    Full Text Available There is a rapidly growing body of evidence that production of microvesicles (MVs is a universal feature of cellular life. MVs can incorporate microRNA (miRNA, mRNA, mtDNA, DNA and retrotransposons, camouflage viruses/viral components from immune surveillance, and transfer cargo between cells. These properties make MVs an essential player in intercellular communication. Increasing evidence supports the notion that MVs can also act as long-distance vehicles for RNA molecules and participate in metabolic synchronization and reprogramming eukaryotic cells including stem and germinal cells. MV ability to carry on DNA and their general distribution makes them attractive candidates for horizontal gene transfer, particularly between multi-cellular organisms and their parasites; this suggests important implications for the co-evolution of parasites and their hosts.In this review, we provide current understanding of the roles played by MVs in intracellular pathogens and parasitic infections. We also discuss the possible role of MVs in co-infection and host shifting.

  5. Transcriptomic changes in zebrafish embryos and larvae following benzo[a]pyrene exposure

    Science.gov (United States)

    Benzo[a]pyrene (BaP) is an environmentally relevant carcinogenic and endocrine disrupting compound that causes immediate, long-term, and multigenerational health deficits in mammals and fish. Previously, we found that BaP alters DNA methylation patterns in developing zebrafish, which may affect gene...

  6. Benzo[a]pyrene decreases global and gene specific DNA methylation during zebrafish development

    Science.gov (United States)

    DNA methylation is important for gene regulation and is vulnerable to early-life exposure to environmental contaminants. We found that direct waterborne benzo[a]pyrene (BaP) exposure at 24 'g/L from 2.5 to 96 hours post fertilization (hpf) to zebrafish embryos significantly decreased global cytosine...

  7. Benzo(A)pyrene Decreases Brain and Ovarian Aromatase mRNA Expression

    Science.gov (United States)

    The higher molecular weight polycyclic aromatic hydrocarbons (PAHs) such as benzo(a)pyrene (BaP) are typically associated with genotoxicity, however newer evidence suggests that these compounds may also act as endocrine system disruptors. We hypothesized that a target for reproductive or development...

  8. Metabolic activation and DNA binding of benzo(a)pyrene in cultured human bronchus

    DEFF Research Database (Denmark)

    1977-01-01

    Human bronchus is one target site for the carcinogenic action of tobacco smoke, which contains chemical carcinogens, including benzo(a)pyrene. Human bronchi were obtained from surgery or “immediate” autopsy and then cultured in a chemically defined medium. The cultured bronchi were exposed...

  9. An investigation of endocrine disrupting effects and toxic mechanisms modulated by benzo[a]pyrene in female scallop Chlamys farreri

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Shuangmei; Pan, Luqing, E-mail: panlq@ouc.edu.cn; Sun, Xiaohua

    2013-11-15

    Highlights: •B[a]P disturbed progesterone, 17β-estradiol and testosterone production in scallop. •B[a]P inhibited 3β-HSD, CYP17 and 17β-HSD expression after a 10-day exposure. •B[a]P of lower dose elevated AHR-CYP1A expression but high dose B[a]P inhibited them. •ER and vitellogenin transcription was consistent with AHR after B[a]P exposure. •B[a]P exposure induced relatively developmental delay and impairment of ovary. -- Abstract: The purpose of this study was to investigate the endocrine disrupting effects induced by benzo[a]pyrene (B[a]P) and explore the underlying mechanisms in mollusks. In this study, sexually mature female Chlamys farreri were exposed to benzo[a]pyrene for 10 days at four different concentrations as 0, 0.025, 0.5 and 10 μg/L. Sex steroids were identified and quantified by electrochemiluminescence immunoassay (ECLIA) method and results showed that exposure to B[a]P exerts great suppression on 17β-estradiol, testosterone production and disrupts progesterone levels in ovary. Transcription of genes were detected and measured by real-time RT-PCR. It showed that at day 10 B[a]P inhibited 3β-HSD, CYP17 and 17β-HSD mRNA expression in a dose-dependent manner, which suggests that they could be potential targets of B[a]P that disrupt steroidogenic machinery. Moreover, 0.025 μg/L B[a]P activated transcription of aryl hydrocarbon receptor (AHR), AHR nuclear translocator (ARNT), CYP1A1 and estrogen receptor (ER), while 10 μg/L B[a]P suppressed all of them. The consistency of their responses to B[a]P exposure implies that AHR action may be involved in invertebrate CYP regulation and ER transcription despite of unknown mechanisms. Additionally, B[a]P exposure could induce ovarian impairment and developmental delay in C. farreri. Overall, sensitivity of C. farreri to endocrine disruption and toxicity suggests that C. farreri is a suitable species for study of endocrine-disrupting effects in marine invertebrates. This study will form a

  10. Human osteoblastic cells propagate intercellular calcium signals by two different mechanisms

    DEFF Research Database (Denmark)

    Jørgensen, Niklas Rye; Henriksen, Z; Brot, C;

    2000-01-01

    Effective bone remodeling requires the coordination of bone matrix deposition by osteoblastic cells, which may occur via soluble mediators or via direct intercellular communication. We have previously identified two mechanisms by which rat osteoblastic cell lines coordinate calcium signaling among...... intercellular calcium signaling, and if so, by which mechanisms. Upon mechanical stimulation, human osteoblasts propagated fast intercellular calcium waves, which required activation of P2 receptors and release of intracellular calcium stores but did not require calcium influx or gap junctional communication....... After the fast intercellular calcium waves were blocked, we observed slower calcium waves that were dependent on gap junctional communication and influx of extracellular calcium. These results show that human osteoblastic cells can propagate calcium signals from cell to cell by two markedly different...

  11. Intercellular adhesion molecule-1 in patients with idiopathic interstitial pneumonia.

    Directory of Open Access Journals (Sweden)

    Takehara H

    2001-08-01

    Full Text Available This study focuses on a possible role of intercellular adhesion molecule-1 (ICAM-1 in interstitial pulmonary diseases. We determined a soluble form of ICAM-1 in serum and bronchoalveolar lavage fluid (BALF using ELISA in patients with usual interstitial pneumonia (UIP, bronchiolitis obliterance organizing pneumonia (BOOP, or nonspecific interstitial pneumonia (NSIP. In addition, we investigated the expression of ICAM-1 in the lung tissues of these patients by means of immunohistochemical staining. Serum levels of soluble ICAM-1 were significantly higher in patients with UIP or NSIP than in healthy subjects, and were also high in patients with BOOP. The soluble ICAM-1 in BALF tended to be higher in patients with UIP, BOOP, or NSIP than in normal subjects. A significant correlation was seen between soluble levels of ICAM-1 in serum and BALF. In the immunostaining of ICAM-1 of the lung tissues, ICAM-1 expression was more pronounced in patients with UIP than in those with BOOP or NSIP. The increased expression of ICAM-1 was seen in type II alveolar epithelium and vascular endothelium in patients with interstitial pneumonia. A positive correlation was observed between the degree of ICAM-1 expression in the lung tissues and the BALF levels of soluble ICAM-1. The expression of ICAM-1 in type II alveolar epithelium suggests that ICAM-1 plays a specific role in the fibrotic process of the lung, and that the measurement of soluble ICAM-1 in sera and BALF could be a useful marker for evaluating the progression of fibrosis.

  12. Telocytes in their context with other intercellular communication agents.

    Science.gov (United States)

    Edelstein, Lawrence; Fuxe, Kjell; Levin, Michael; Popescu, Bogdan O; Smythies, John

    2016-07-01

    The past decade has borne witness to an explosion in our understanding of the fundamental complexities of intercellular communication. Previously, the field was solely defined by the simple exchange of endocrine, autocrine and epicrine agents. Then it was discovered that cells possess an elaborate system of extracellular vesicles, including exosomes, which carry a vast array of small and large molecules (including many epigenetic agents such as a variety RNAs and DNA), as well as large organelles that modulate almost every aspect of cellular function. In addition, it was thought that electrical communication between cells was limited mainly to neurotransmitters and neuromodulators in the nervous system. Also within the past decade, it was found that - in addition to neurons - most cells (both mammalian and non-mammalian) communicate via elaborate bioelectric systems which modulate many fundamental cellular processes including growth, differentiation, morphogenesis and repair. In the nervous system, volume transmission via the extracellular matrix has been added to the list. Lastly, it was discovered that what had previously been regarded as simple connective cells in most tissues proved to be miniature communication devices now known as telocytes. These unusually long, tenuous and sinuous cells utilize elaborate electrical, chemical and epigenetic mechanisms, including the exchange of exosomes, to integrate many activities within and between nearly all types of cells in tissues and organs. Their interrelationship with neural stem cells and neurogenesis in the context of neurodegenerative disease is just beginning to be explored. This review presents an account of precisely how each of these varied mechanisms are relevant and critical to the understanding of what telocytes are and how they function. PMID:27013113

  13. Activation of L-type calcium channels is required for gap junction-mediated intercellular calcium signaling in osteoblastic cells

    Science.gov (United States)

    Jorgensen, Niklas Rye; Teilmann, Stefan Cuoni; Henriksen, Zanne; Civitelli, Roberto; Sorensen, Ole Helmer; Steinberg, Thomas H.

    2003-01-01

    The propagation of mechanically induced intercellular calcium waves (ICW) among osteoblastic cells occurs both by activation of P2Y (purinergic) receptors by extracellular nucleotides, resulting in "fast" ICW, and by gap junctional communication in cells that express connexin43 (Cx43), resulting in "slow" ICW. Human osteoblastic cells transmit intercellular calcium signals by both of these mechanisms. In the current studies we have examined the mechanism of slow gap junction-dependent ICW in osteoblastic cells. In ROS rat osteoblastic cells, gap junction-dependent ICW were inhibited by removal of extracellular calcium, plasma membrane depolarization by high extracellular potassium, and the L-type voltage-operated calcium channel inhibitor, nifedipine. In contrast, all these treatments enhanced the spread of P2 receptor-mediated ICW in UMR rat osteoblastic cells. Using UMR cells transfected to express Cx43 (UMR/Cx43) we confirmed that nifedipine sensitivity of ICW required Cx43 expression. In human osteoblastic cells, gap junction-dependent ICW also required activation of L-type calcium channels and influx of extracellular calcium.

  14. Intercellular transfer of P-glycoprotein in human blood-brain barrier endothelial cells is increased by histone deacetylase inhibitors.

    Science.gov (United States)

    Noack, Andreas; Noack, Sandra; Buettner, Manuela; Naim, Hassan Y; Löscher, Wolfgang

    2016-01-01

    The blood-brain barrier (BBB) controls the entry of compounds into the brain, thereby regulating brain homeostasis. Efflux transporters such as P-glycoprotein (Pgp) significantly contribute to BBB function. Multiple signaling pathways modulate the expression and activity of Pgp in response to xenobiotics and disease. A non-genetic way of intercellular transfer of Pgp occurs in cancer cells, but whether this also occurs in non-cancer cells such as endothelial cells that form the BBB is not known. A human brain endothelial cell line (hCMEC/D3) was used to study whether cell-to-cell Pgp transfer occurs during co-culturing with Pgp-EGFP expressing hCMEC/D3 cells. The Pgp-EGFP fusion protein was transferred from donor to recipient cells by cell-to-cell contact and Pgp-EGFP enriched vesicles, which were exocytosed by donor cells and endocytosed by adherent recipient cells. Flow cytometry experiments with the Pgp substrate eFLUXX-ID Gold demonstrated that the transferred Pgp is functional in the recipient cells. Exposure of the donor cells with inhibitors of histone deacetylases (HDACs) resulted in an enhanced intercellular Pgp transfer. Non-genetic transfer of a resistance phenotype and its regulation by HDACs is a novel mechanism of altering BBB functionality. This mechanism may have important implications for understanding drug-induced alterations in Pgp expression and activity. PMID:27375084

  15. Mammalian Tissue Response to Low Dose Ionizing Radiation: The Role of Oxidative Metabolism and Intercellular Communication

    Energy Technology Data Exchange (ETDEWEB)

    Azzam, Edouard I

    2013-01-16

    The objective of the project was to elucidate the mechanisms underlying the biological effects of low dose/low dose rate ionizing radiation in organs/tissues of irradiated mice that differ in their susceptibility to ionizing radiation, and in human cells grown under conditions that mimic the natural in vivo environment. The focus was on the effects of sparsely ionizing cesium-137 gamma rays and the role of oxidative metabolism and intercellular communication in these effects. Four Specific Aims were proposed. The integrated outcome of the experiments performed to investigate these aims has been significant towards developing a scientific basis to more accurately estimate human health risks from exposures to low doses ionizing radiation. By understanding the biochemical and molecular changes induced by low dose radiation, several novel markers associated with mitochondrial functions were identified, which has opened new avenues to investigate metabolic processes that may be affected by such exposure. In particular, a sensitive biomarker that is differentially modulated by low and high dose gamma rays was discovered.

  16. Exosomes as Intercellular Signaling Organelles Involved in Health and Disease: Basic Science and Clinical Applications

    Directory of Open Access Journals (Sweden)

    Francesco Ciccia

    2013-03-01

    Full Text Available Cell to cell communication is essential for the coordination and proper organization of different cell types in multicellular systems. Cells exchange information through a multitude of mechanisms such as secreted growth factors and chemokines, small molecules (peptides, ions, bioactive lipids and nucleotides, cell-cell contact and the secretion of extracellular matrix components. Over the last few years, however, a considerable amount of experimental evidence has demonstrated the occurrence of a sophisticated method of cell communication based on the release of specialized membranous nano-sized vesicles termed exosomes. Exosome biogenesis involves the endosomal compartment, the multivesicular bodies (MVB, which contain internal vesicles packed with an extraordinary set of molecules including enzymes, cytokines, nucleic acids and different bioactive compounds. In response to stimuli, MVB fuse with the plasma membrane and vesicles are released in the extracellular space where they can interact with neighboring cells and directly induce a signaling pathway or affect the cellular phenotype through the transfer of new receptors or even genetic material. This review will focus on exosomes as intercellular signaling organelles involved in a number of physiological as well as pathological processes and their potential use in clinical diagnostics and therapeutics.

  17. Connexin expression and gap-junctional intercellular communication in ES cells and iPS cells

    Directory of Open Access Journals (Sweden)

    Masahito eOyamada

    2013-07-01

    Full Text Available Pluripotent stem cells, i.e., embryonic stem (ES and induced pluripotent stem (iPS cells, can indefinitely proliferate without commitment and differentiate into all cell lineages. ES cells are derived from the inner cell mass of the preimplantation blastocyst, whereas iPS cells are generated from somatic cells by overexpression of a few transcription factors. Many studies have demonstrated that mouse and human iPS cells are highly similar but not identical to their respective ES cell counterparts. The potential to generate basically any differentiated cell types from these cells offers the possibility to establish new models of mammalian development and to create new sources of cells for regenerative medicine. ES cells and iPS cells also provide useful models to study connexin expression and gap-junctional intercellular communication (GJIC during cell differentiation and reprogramming. In 1996, we reported connexin expression and GJIC in mouse ES cells. Because a substantial number of papers on these subjects have been published since our report, this Mini Review summarizes currently available data on connexin expression and GJIC in ES cells and iPS cells during undifferentiated state, differentiation, and reprogramming.

  18. Proteomic insights into intra- and intercellular plant-bacteria symbiotic association during root nodule formation

    Directory of Open Access Journals (Sweden)

    Afshin eSalavati

    2013-02-01

    Full Text Available Over the last several decades, there have been a large number of studies done on the all aspects of legumes and bacteria which participate in nitrogen-fixing symbiosis. The analysis of legume-bacteria interaction is not just a matter of numerical complexity in terms of variants of gene products that can arise from a single gene. Bacteria regulate their quorum-sensing genes to enhance their ability to induce conjugation of plasmids and symbiotic islands, and various protein secretion mechanisms; that can stimulate a collection of chain reactions including species-specific combinations of plant-secretion isoflavonoids, complicated calcium signaling pathways and autoregulation of nodulation mechanisms. Quorum-sensing systems are introduced by the intra- and intercellular organization of gene products lead to protein–protein interactions or targeting of proteins to specific cellular structures. In this study, an attempt has been made to review significant contributions related to nodule formation and development and their impacts on cell proteome for better understanding of plant-bacterium interaction mechanism at protein level. This review would not only provide new insights into the plant-bacteria symbiosis response mechanisms but would also highlights the importance of studying changes in protein abundance inside and outside of cells in response to symbiosis. Furthermore, the application to agriculture programe of plant-bacteria interaction will be discussed.

  19. Alterations to proteome and tissue recovery responses in fish liver caused by a short-term combination treatment with cadmium and benzo[a]pyrene

    Energy Technology Data Exchange (ETDEWEB)

    Costa, P.M., E-mail: pmcosta@fct.unl.p [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Monte de Caparica (Portugal); Chicano-Galvez, E.; Lopez Barea, J. [Departamento de Bioquimica y Biologia Molecular, Universidad de Cordoba, Campus de Rabanales, Edificio Severo Ochoa, 14071 Cordoba (Spain); DelValls, T.A. [UNESCO/UNITWIN/WiCop Chair-Departamento de Quimica Fisica, Facultad de Ciencias del Mar y Ambientales, Universidad de Cadiz, Poligono rio San Pedro s/n, 11510 Puerto Real, Cadiz (Spain); Costa, M.H. [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Monte de Caparica (Portugal)

    2010-10-15

    The livers of soles (Solea senegalensis) injected with subacute doses of cadmium (Cd), benzo[a]pyrene (B[a]P), or their combination, were screened for alterations to cytosolic protein expression patterns, complemented by cytological and histological analyses. Cadmium and B[a]P, but not combined, induced hepatocyte apoptosis and Kupfer cell hyperplasia. Proteomics, however, suggested that apoptosis was triggered through distinct pathways. Cadmium and B[a]P caused upregulation of different anti-oxidative enzymes (peroxiredoxin and glutathione peroxidase, respectively) although co-exposure impaired induction. Similarly, apoptosis was inhibited by co-exposure, to which may have contributed a synergistic upregulation of tissue metalloproteinase inhibitor, {beta}-actin and a lipid transport protein. The regulation factors of nine out of eleven identified proteins of different types revealed antagonistic or synergistic effects between Cd and B[a]P at the prospected doses after 24 h of exposure. The results indicate that co-exposure to Cd and B[a]P may enhance toxicity by impairing specific responses and not through cumulative damage. - The interaction between cadmium and benzo[a]pyrene impairs specific responses to toxicity and tissue repair mechanisms.

  20. Metabolites of benzene are potent inhibitors of gap-junction intercellular communication

    Energy Technology Data Exchange (ETDEWEB)

    Rivedal, Edgar [Norwegian Radium Hospital, Institute for Cancer Research, Montebello, Oslo (Norway); Witz, Gisela [Robert Wood Johnson Medical School/UMDNJ, Environmental and Occupational Health Sciences Institute and Department of Environmental and Occupational Medicine, Piscataway, New Jersey (United States)

    2005-06-01

    Chronic exposure to benzene has been shown to lead to bone marrow depression and the development of leukemia. The mechanism underlying the carcinogenicity of benzene is unknown, although a number of genetic changes including chromosomal aberrations have been associated with benzene toxicity. Metabolism of benzene is required for the induced toxicological effects. We have investigated the effect of trans,trans-muconaldehyde (MUC), hydroquinone (HQ), and four MUC metabolites on gap-junction intercellular communication (GJIC). Inhibition of GJIC has been considered a possible predictor of tumor promoters and non-genotoxic carcinogens, and shown to result in perturbation of hematopoiesis. MUC was found to be a strong inhibitor of GJIC (EC50=12 {mu}mol L{sup -1}) in rat liver epithelial cells IAR20, with potency similar to that of chlordane (EC50=7 {mu}mol L{sup -1}). HQ inhibited GJIC with an EC50 of 25 {mu}mol L{sup -1}, and the metabolite OH/CHO with an EC50 of 58 {mu}mol L{sup -1}. The other MUC metabolites tested, CHO/COOH and OH/COOH were weak inhibitors of GJIC whereas COOH/COOH had no effect. Benzene itself had no effect on GJIC when tested in concentrations up to 20 mmol L{sup -1}. The relative potency observed for the metabolites on GJIC is similar to their hematotoxic effects. The effect of MUC on GJIC was observed to take place concordant with a dramatic loss of connexin 43 (Cx43) from the cells as visualized by Western blotting. Substances with the ability to inhibit Cx43-dependent GJIC have previously been observed to interfere with normal hematopoietic development. The ability of benzene metabolites to interfere with gap-junction functionality, and especially the dramatic loss of Cx43 induced by MUC, should therefore be considered as a possible mechanism for benzene-induced hematotoxicity and development of leukemia. (orig.)

  1. Overexpression of Catalase Enhances Benzo(a)pyrene Detoxification in Endothelial Microsomes

    Science.gov (United States)

    Yang, Fang; Yang, Hong; Ramesh, Aramandla; Goodwin, J. Shawn; Okoro, Emmanuel U.; Guo, ZhongMao

    2016-01-01

    We previously reported that overexpression of catalase upregulated xenobiotic- metabolizing enzyme (XME) expression and diminished benzo(a)pyrene (BaP) intermediate accumulation in mouse aortic endothelial cells (MAECs). Endoplasmic reticulum (ER) is the most active organelle involved in BaP metabolism. To examine the involvement of ER in catalase-induced BaP detoxification, we compared the level and distribution of XMEs, and the profile of BaP intermediates in the microsomes of wild-type and catalase transgenic endothelial cells. Our data showed that endothelial microsomes were enriched in cytochrome P450 (CYP) 1A1, CYP1B1 and epoxide hydrolase 1 (EH1), and contained considerable levels of NAD(P)H: quinone oxidoreductase-1 (NQO1) and glutathione S-transferase-pi (GSTP). Treatment of wild-type MAECs with 1μM BaP for 2 h increased the expression of microsomal CYP1A1, 1B1 and NQO1 by ~300, 64 and 116%, respectively. However, the same treatment did not significantly alter the expression of EH1 and GSTP. Overexpression of catalase did not significantly increase EH1, but upregulated BaP-induced expression of microsomal CYP1A1, 1B1, NQO1 and GSTP in the following order: 1A1>NQO1>GSTP>1B1. Overexpression of catalase did not alter the distribution of each of these enzymes in the microsomes. In contrast to our previous report showing lower level of BaP phenols versus BaP diols/diones in the whole-cell, this report demonstrated that the sum of microsomal BaP phenolic metabolites were ~60% greater than that of the BaP diols/diones after exposure of microsomes to BaP. Overexpression of catalase reduced the concentrations of microsomal BaP phenols and diols/diones by ~45 and 95%, respectively. This process enhanced the ratio of BaP phenol versus diol/dione metabolites in a potent manner. Taken together, upregulation of phase II XMEs and CYP1 proteins, but not EH1 in the ER might be the mechanism by which overexpression of catalase reduces the levels of all the BaP metabolites

  2. Relation of hepatic EROD activity and CYP1A level in Sebastiscus marmoratus exposed to benzo[a]pyrene

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This study was designed to investigate the in vivo effects of benzo[a]pyrene (BaP) on hepatic ethoxyresorufin-O-deethylase (EROD) activity and its correlation with cytochrome P450 1A (CYP1A) protein levels in Sebastiscus marmoratus, which were exposed through a water column to BaP (10, 100, 1000 ng/L, respectively) or were treated with intraperitoneal injections of BaP (0.5, 1, 5, 10 mg/kg, respectively) every 7 d. The results showed that after 25 d of waterborne exposure to 1000 ng/L BaP, fish hepatic CYP1A levels and EROD activity were significantly induced. In contrast, EROD activity was not altered 7 d after second ip injections, whereas, CYP1A protein levels were increased. Dose-dependent increase of biliary BaP metabolites demonstrated that the catalytic activity of CYP1A was induced by treatment with BaP. The lowest observable effect concentration with regard to biliary BaP metabolites (100 ng/L) was much lower than that with reference to EROD activity (1000 ng/L). The results suggest that biliary polycyclic aromatic hydrocarbon (PAH) metabolites were shown to better reflect the contamination gradients of PAHs than EROD activity. It appeared to be necessary to measure CYP1A protein levels to complement the EROD activity in relevant toxicological assessments.

  3. Flow cytometric measurement of the metabolism of benzo[a]pyrene by mouse liver cells in culture

    International Nuclear Information System (INIS)

    The metabolism of benzo[a]pyrene in individual cells was monitored by flow cytometry. The measurements are based on the alterations that occur in the fluorescence emission spectrum of benzo[a]pyrene when it is converted to various metabolites. Using present instrumentation the technique could easily detect 1x106 molecules per cells of benzo[a]pyrene and 1x107 molecules per cell of the diol epoxide. The analysis of C3H IOT 1/2 mouse fibroblasts growing in culture indicated that there was heterogeneity in the conversion of the parent compound into diol epoxide derivatives suggesting that some variation in sensitivity to transformation by benzo[a]pyrene may be due to differences in cellular metabolism. The technique allows sensitive detection of metabolites in viable cells, and provides a new approach to the study of factors that influence both metabolism and transformation. (orig.)

  4. Influence of cell cycle on responses of MCF-7 cells to benzo[a]pyrene

    Directory of Open Access Journals (Sweden)

    Giddings Ian

    2011-06-01

    Full Text Available Abstract Background Benzo[a]pyrene (BaP is a widespread environmental genotoxic carcinogen that damages DNA by forming adducts. This damage along with activation of the aryl hydrocarbon receptor (AHR induces complex transcriptional responses in cells. To investigate whether human cells are more susceptible to BaP in a particular phase of the cell cycle, synchronised breast carcinoma MCF-7 cells were exposed to BaP. Cell cycle progression was analysed by flow cytometry, DNA adduct formation was assessed by 32P-postlabeling analysis, microarrays of 44K human genome-wide oligos and RT-PCR were used to detect gene expression (mRNA changes and Western blotting was performed to determine the expression of some proteins, including cytochrome P450 (CYP 1A1 and CYP1B1, which are involved in BaP metabolism. Results Following BaP exposure, cells evaded G1 arrest and accumulated in S-phase. Higher levels of DNA damage occurred in S- and G2/M- compared with G0/G1-enriched cultures. Genes that were found to have altered expression included those involved in xenobiotic metabolism, apoptosis, cell cycle regulation and DNA repair. Gene ontology and pathway analysis showed the involvement of various signalling pathways in response to BaP exposure, such as the Catenin/Wnt pathway in G1, the ERK pathway in G1 and S, the Nrf2 pathway in S and G2/M and the Akt pathway in G2/M. An important finding was that higher levels of DNA damage in S- and G2/M-enriched cultures correlated with higher levels of CYP1A1 and CYP1B1 mRNA and proteins. Moreover, exposure of synchronised MCF-7 cells to BaP-7,8-diol-9,10-epoxide (BPDE, the ultimate carcinogenic metabolite of BaP, did not result in significant changes in DNA adduct levels at different phases of the cell cycle. Conclusions This study characterised the complex gene response to BaP in MCF-7 cells and revealed a strong correlation between the varying efficiency of BaP metabolism and DNA damage in different phases of the cell

  5. A common carcinogen benzo[a]pyrene causes neuronal death in mouse via microglial activation.

    Directory of Open Access Journals (Sweden)

    Kallol Dutta

    Full Text Available BACKGROUND: Benzo[a]pyrene (B[a]P belongs to a class of polycyclic aromatic hydrocarbons that serve as micropollutants in the environment. B[a]P has been reported as a probable carcinogen in humans. Exposure to B[a]P can take place by ingestion of contaminated (especially grilled, roasted or smoked food or water, or inhalation of polluted air. There are reports available that also suggests neurotoxicity as a result of B[a]P exposure, but the exact mechanism of action is unknown. METHODOLOGY/PRINCIPAL FINDINGS: Using neuroblastoma cell line and primary cortical neuron culture, we demonstrated that B[a]P has no direct neurotoxic effect. We utilized both in vivo and in vitro systems to demonstrate that B[a]P causes microglial activation. Using microglial cell line and primary microglial culture, we showed for the first time that B[a]P administration results in elevation of reactive oxygen species within the microglia thereby causing depression of antioxidant protein levels; enhanced expression of inducible nitric oxide synthase, that results in increased production of NO from the cells. Synthesis and secretion of proinflammatory cytokines were also elevated within the microglia, possibly via the p38MAP kinase pathway. All these factors contributed to bystander death of neurons, in vitro. When administered to animals, B[a]P was found to cause microglial activation and astrogliosis in the brain with subsequent increase in proinflammatory cytokine levels. CONCLUSIONS/SIGNIFICANCE: Contrary to earlier published reports we found that B[a]P has no direct neurotoxic activity. However, it kills neurons in a bystander mechanism by activating the immune cells of the brain viz the microglia. For the first time, we have provided conclusive evidence regarding the mechanism by which the micropollutant B[a]P may actually cause damage to the central nervous system. In today's perspective, where rising pollution levels globally are a matter of grave concern, our

  6. Occupational exposure to coal tar pitch volatiles, benzo/a/pyrene and dust in tyre production.

    Science.gov (United States)

    Rogaczewska, T; Ligocka, D

    1994-01-01

    Occupational exposure to coal tar pitch volatiles (CTPVs), benzo/a/pyrene (BaP) and dust was evaluated by means of individual measurements carried out in 80 workers and by stationary measurements on 16 work-posts in two divisions of the tyre producing plant. Dust and coal tar pitch volatiles concentrations in the air were determinated by the gravimetric method, measured, in the case of CPTVs, benzene-soluble fraction (BSF) with ultrasonic extraction. Benzo/a/pyrene analysis was performed using high performance liquid chromato-graphy (HPLC) with a spectrofluorimetric detector. It was found that nearly all personal sampling results for BaP were within the range 90%) which exceeded the admissible value (4 mg/m3) was found mainly only in the workers of the Semiproducts Division at some work-posts.

  7. Benzo(a)pyrene activation and detoxification by human pulmonary alveolar macrophages and lymphocytes

    International Nuclear Information System (INIS)

    Comparisons of pulmonary alveolar macrophages and circulating lymphocytes from five smokers and five nonsmokers for their ability to metabolize benzo(a)pyrene as determined by high pressure liquid chromatography were carried out. Utilizing this approach, further investigation of activation and detoxification by several human cell types could provide the basis for more precise and comprehensive studies of carcinogen and drug metabolism in the human lung, and for a better assessment of cancer risk in selected populations

  8. Benzo(a)pyrene diolepoxide-DNA adducts detected by synchronous fluorescence spectrophotometry.

    OpenAIRE

    Vahakangas, K.; Trivers, G; Rowe, M.; Harris, C. C.

    1985-01-01

    Using benzo(a)pyrene (BP) as a model carcinogen we are currently applying a fluorescence technique to detect the very low levels of carcinogen-DNA adducts in human populations due to environmental exposure. In synchronous fluorescence spectrophotometry for detection of BP-diol epoxide-DNA, excitation and emission wavelengths are scanned simultaneously with a fixed wavelength difference (delta lambda) of 34 nm. Compared to conventional fluorescence methods only one peak emerges because excitat...

  9. Intercellular ultrafast Ca(2+) wave in vascular smooth muscle cells: numerical and experimental study.

    Science.gov (United States)

    Quijano, J C; Raynaud, F; Nguyen, D; Piacentini, N; Meister, J J

    2016-01-01

    Vascular smooth muscle cells exhibit intercellular Ca(2+) waves in response to local mechanical or KCl stimulation. Recently, a new type of intercellular Ca(2+) wave was observed in vitro in a linear arrangement of smooth muscle cells. The intercellular wave was denominated ultrafast Ca(2+) wave and it was suggested to be the result of the interplay between membrane potential and Ca(2+) dynamics which depended on influx of extracellular Ca(2+), cell membrane depolarization and its intercel- lular propagation. In the present study we measured experimentally the conduction velocity of the membrane depolarization and performed simulations of the ultrafast Ca(2+) wave along coupled smooth muscle cells. Numerical results reproduced a wide spectrum of experimental observations, including Ca(2+) wave velocity, electrotonic membrane depolarization along the network, effects of inhibitors and independence of the Ca(2+) wave speed on the intracellular stores. The numerical data also provided new physiological insights suggesting ranges of crucial model parameters that may be altered experimentally and that could significantly affect wave kinetics allowing the modulation of the wave characteristics experimentally. Numerical and experimental results supported the hypothesis that the propagation of membrane depolarization acts as an intercellular messenger mediating intercellular ultrafast Ca(2+) waves in smooth muscle cells. PMID:27507785

  10. Intercellular ultrafast Ca2+ wave in vascular smooth muscle cells: numerical and experimental study

    Science.gov (United States)

    Quijano, J. C.; Raynaud, F.; Nguyen, D.; Piacentini, N.; Meister, J. J.

    2016-01-01

    Vascular smooth muscle cells exhibit intercellular Ca2+ waves in response to local mechanical or KCl stimulation. Recently, a new type of intercellular Ca2+ wave was observed in vitro in a linear arrangement of smooth muscle cells. The intercellular wave was denominated ultrafast Ca2+ wave and it was suggested to be the result of the interplay between membrane potential and Ca2+ dynamics which depended on influx of extracellular Ca2+, cell membrane depolarization and its intercel- lular propagation. In the present study we measured experimentally the conduction velocity of the membrane depolarization and performed simulations of the ultrafast Ca2+ wave along coupled smooth muscle cells. Numerical results reproduced a wide spectrum of experimental observations, including Ca2+ wave velocity, electrotonic membrane depolarization along the network, effects of inhibitors and independence of the Ca2+ wave speed on the intracellular stores. The numerical data also provided new physiological insights suggesting ranges of crucial model parameters that may be altered experimentally and that could significantly affect wave kinetics allowing the modulation of the wave characteristics experimentally. Numerical and experimental results supported the hypothesis that the propagation of membrane depolarization acts as an intercellular messenger mediating intercellular ultrafast Ca2+ waves in smooth muscle cells. PMID:27507785

  11. Modulation of Intercellular Junction by Utilization of Cadherin Peptides as an Effort to Improve Drug Delivery

    Directory of Open Access Journals (Sweden)

    Usman Sumo Friend Tambunan

    2004-04-01

    Full Text Available Rapid advances in combinatorial chemistry and molecular biology has influenced the discovery of many proteins, peptides and peptidomimetics as potential therapeutic agents. Unfortunately, the practical application of these potential drugs is often restricted by the difficulties of delivering them to target site(s due to the presence of biological barriers. Recently, a new method to improve the drug delivery, that is by modulating the intercellular junction, has been evaluated. Modulation of intercellular junction could be achieved by modulating the proteins which play important role in establishing the intercellular junction, one of which is cadherin. In the present work we have demonstrated the ability of several cadherin peptides, i.e. Ac-LFSHAVSSNG-NH2 (HAV-10, Ac-SHAVSS-NH2 (HAV-6, Ac-QGADTPPVGV-NH2 (ADT-10, and Ac-ADTPPV-NH2 (ADT-6 to modulate the intercellular junction of MDCK (Madin Darby Canine Kidney cells, this finding is a contribution to the establishment of a new method to improve the drug delivery by utilization of cadherin peptides by modulating the intercellular junction.

  12. Modulatory effects of cAMP and PKC activation on gap junctional intercellular communication among thymic epithelial cells

    Directory of Open Access Journals (Sweden)

    Neves-dos-Santos Sandra

    2010-01-01

    Full Text Available Abstract Background We investigated the effects of the signaling molecules, cyclic AMP (cAMP and protein-kinase C (PKC, on gap junctional intercellular communication (GJIC between thymic epithelial cells (TEC. Results Treatment with 8-Br-cAMP, a cAMP analog; or forskolin, which stimulates cAMP production, resulted in an increase in dye transfer between adjacent TEC, inducing a three-fold enhancement in the mean fluorescence of coupled cells, ascertained by flow cytometry after calcein transfer. These treatments also increased Cx43 mRNA expression, and stimulated Cx43 protein accumulation in regions of intercellular contacts. VIP, adenosine, and epinephrine which may also signal through cyclic nucleotides were tested. The first two molecules did not mimic the effects of 8-Br-cAMP, however epinephrine was able to increase GJIC suggesting that this molecule functions as an endogenous inter-TEC GJIC modulators. Stimulation of PKC by phorbol-myristate-acetate inhibited inter-TEC GJIC. Importantly, both the enhancing and the decreasing effects, respectively induced by cAMP and PKC, were observed in both mouse and human TEC preparations. Lastly, experiments using mouse thymocyte/TEC heterocellular co-cultures suggested that the presence of thymocytes does not affect the degree of inter-TEC GJIC. Conclusions Overall, our data indicate that cAMP and PKC intracellular pathways are involved in the homeostatic control of the gap junction-mediated communication in the thymic epithelium, exerting respectively a positive and negative role upon cell coupling. This control is phylogenetically conserved in the thymus, since it was seen in both mouse and human TEC preparations. Lastly, our work provides new clues for a better understanding of how the thymic epithelial network can work as a physiological syncytium.

  13. Alterations in the metabolism of benzo(a)pyrene in syrian hamster embryo (SHE) cells pretreated with phenolic antioxidants

    Energy Technology Data Exchange (ETDEWEB)

    Strniste, G.F.; Okinaka, R.T.; Chen, D.J.

    1983-01-01

    Inhibition of chemical- or raddiation-induced neoplasia has been observed in animals whose diets were supplemented with antioxidants commonly used as food additives. Inhibition of the carcinogenicity of benzo(a)pyrene (BaP) or of 7,12-dimenthylbenz(a)anthracene (DMBA) - in rats has been achieved by the addition of the phenolic antioxidants butylated hydroxyanisole (BHA) or butylated hydroxytoluene (BHT) to the diet. Our data suggest that in SHE cells antioxidants inhibit the overall metabolism of BaP to its various oxidized moieties including 7,8-diol- and 7,8,9,10-tetrol-BaP. A plausible explanation for our results with SHE cells is that the antioxidants interact directly with AHH, thus inhibiting AHH metabolic capacity. From analysis of nuclear material from SHE cells (+- antioxidants) incubated for 36 hours with BaP at 1 ..mu..g/ml, it is calculated that 4.6, 2.4 and 2.9 pmol BaP are bound to the DNA isolated from 10/sup 7/ nuclei of control, BHA-(20 ..mu..g/ml) and p-MP-(10 ..mu..g/ml) treated cultures, respectively.

  14. Intercellular adhesion molecule-1 expression by skeletal muscle cells augments myogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Goh, Qingnian; Dearth, Christopher L.; Corbett, Jacob T. [Department of Kinesiology, The University of Toledo, Toledo, OH (United States); Pierre, Philippe [Centre d’Immunologie de Marseille-Luminy U2M, Aix-Marseille Université, Marseille (France); INSERM U631, Institut National de la Santé et Recherche Médicale, Marseille (France); CNRS UMR6102, Centre National de la Recherche Scientifique, Marseille (France); Chadee, Deborah N. [Department of Biological Sciences, The University of Toledo, Toledo, OH (United States); Pizza, Francis X., E-mail: Francis.Pizza@utoledo.edu [Department of Kinesiology, The University of Toledo, Toledo, OH (United States)

    2015-02-15

    We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast–myoblast adhesion, myotube formation, myonuclear number, myotube alignment, myotube–myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube–myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. - Highlights: • We examined mechanisms through which skeletal muscle cell expression of ICAM-1 facilitates events of in vitro myogenesis. • Expression of ICAM-1 by cultured myoblasts did not influence their ability to proliferate or differentiate. • Skeletal muscle cell expression of ICAM-1 augmented myoblast fusion, myotube alignment, myotube–myotube fusion, and myotube size. • ICAM-1 augmented myogenic processes through

  15. Chronic exposure to low benzo[a]pyrene level causes neurodegenerative disease-like syndromes in zebrafish (Danio rerio).

    Science.gov (United States)

    Gao, Dongxu; Wu, Meifang; Wang, Chonggang; Wang, Yuanchuan; Zuo, Zhenghong

    2015-10-01

    Previous epidemiological and animal studies report that exposure to environmental pollutant exposure links to neurodegenerative diseases such as Parkinson's disease and Alzheimer's disease. Benzo[a]pyrene (BaP), a neurotoxic polycyclic aromatic hydrocarbon, has been increasingly released into the environment during recent decades. So far, the role of BaP on the development of neurodegenerative diseases remaind unclear. This study aimed to determine whether chronic exposure to low dose BaP would cause neurodegenerative disease-like syndromes in zebrafish (Danio rerio). We exposed zebrafish, from early embryogenesis to adults, to environmentally relevant concentrations of BaP for 230 days. Our results indicated that BaP decreased the brain weight to body weight ratio, locomotor activity and cognitive ability; induced the loss of dopaminergic neurons; and resulted in neurodegeneration. In addition, obvious cell apoptosis in the brain was found. Furthermore, the neurotransmitter levels of dopamine and 3,4-dihydroxyphenylacetic acid, the mRNA levels of the genes encoding dopamine transporter, Parkinson protein 7, phosphatase and tensin-induced putative kinase 1, ubiquitin carboxy-terminal hydrolase L1, leucine-rich repeat serine/threonine kinase 2, amyloid precursor protein b, presenilin 1 and presenilin 2 were significantly down-regulated by BaP exposure. These findings suggest that chronic exposure to low dose BaP could cause the behavioral, neuropathological, neurochemical, and genetic features of neurodegenerative diseases. This study provides clues that BaP may constitute an important environmental risk factor for neurodegenerative diseases in humans. PMID:26349946

  16. ATP- and gap junction-dependent intercellular calcium signaling in osteoblastic cells

    DEFF Research Database (Denmark)

    Jorgensen, N R; Geist, S T; Civitelli, R;

    1997-01-01

    Many cells coordinate their activities by transmitting rises in intracellular calcium from cell to cell. In nonexcitable cells, there are currently two models for intercellular calcium wave propagation, both of which involve release of inositol trisphosphate (IP3)- sensitive intracellular calcium...

  17. Proteins Play Important Role in Intercellular Adhesion Affecting on Fruit Textural Quality

    DEFF Research Database (Denmark)

    Bahadur Adhikari, Khem; Shomer, Ilan

    2012-01-01

    Fruit textural quality is becoming a major quality parameter for export, postharvest preservation, handling and processing. The main determinant of textural quality is intercellular adhesion (ICA) as attributed by the cell wall (CW) and its components. The importance of CW protein in ICA strength...

  18. Estimation of the effective intercellular diffusion coefficient in cell monolayers coupled by gap junctions

    DEFF Research Database (Denmark)

    Olesen, Niels Erik; Hofgaard, Johannes P; von Holstein-Rathlou, Niels-Henrik;

    2012-01-01

    A recently developed dye-based assay to study gap junction permeability is analysed. The assay is based on electroporation of dye into a large number of connexin 43 expressing cells, grown to confluency on electrically conductive slides. The subsequent intercellular spread of dye to non-electroporated...

  19. Effect of various chemicals on the metabolism of benzo(a)pyrene by cultured rat colon

    DEFF Research Database (Denmark)

    1977-01-01

    The effect of various co- and anti-carcinogens of colon carcinogenesis on the metabolism of benzo(a)pyrene (BP) in cultured rat colon is reported. Rat colon enzymatically converted BP into metabolites which bind to cellular macromolecules i.e., DNA and protein. Activity of aryl hydrocarbon...... hydroxylase (AHH) activity and binding levels of BP to macromolecules were higher in the descending colon when compared to other segments. The major metabolites of BP, extractable with ethylacetate, were quinones, tetrols, 7,8-diol and a peak containing 9,10-dihydroxy-9,10-dihydrobenzo(a)pyrene and 7...

  20. Determination of the level of benzo[a]pyrene in fatty foods and food supplements

    OpenAIRE

    Van Der Wielen-Hustinx, Jacqueline Claire Agnes; Jansen, John; Martena, Martijn J.; De Groot, Henk; In T Veld, Paul

    2006-01-01

    Abstract A routine method was developed for the quantification of benzo[a]pyrene (BaP) in edible oils and food supplements. BaP is often taken as an indicator of the presence of polycyclic aromatic hydrocarbons. The method consists of on-line LC-clean up followed by injection to an HPLC-system connected with fluorescence detection. The method has good performance characteristics and gave good results in proficiency tests. From 2002 to 2004 about 1350 samples, oils and food supp...

  1. INHIBITION OF GAP JUNCTIONAL INTERCELLULAR COMMUNICATION BY PERFLUORINATED COMPOUNDS IN RAT LIVER AND DOLPHIN KIDNEY EPITHELIAL CELL LINES IN VITRO AND SPRAGUE-DAWLEY RATS IN VIVO

    Science.gov (United States)

    Abstract Gap Junctional Intercellular Communication (GJIC) is the major pathway of intercellular signal transduction, and is, thus, important for normal cell growth and function. Recent studies have revealed a global distribution of some perfluorinated organic compounds e...

  2. Toxicogenomic outcomes predictive of forestomach carcinogenesis following exposure to benzo(a)pyrene: Relevance to human cancer risk

    Energy Technology Data Exchange (ETDEWEB)

    Labib, Sarah, E-mail: Sarah.Labib@hc-sc.gc.ca; Guo, Charles H., E-mail: Charles.Guo@hc-sc.gc.ca; Williams, Andrew, E-mail: Andrew.Williams@hc-sc.gc.ca; Yauk, Carole L., E-mail: Carole.Yauk@hc-sc.gc.ca; White, Paul A., E-mail: Paul.White@hc-sc.gc.ca; Halappanavar, Sabina, E-mail: Sabina.Halappanavar@hc-sc.gc.ca

    2013-12-01

    Forestomach tumors are observed in mice exposed to environmental carcinogens. However, the relevance of this data to humans is controversial because humans lack a forestomach. We hypothesize that an understanding of early molecular changes after exposure to a carcinogen in the forestomach will provide mode-of-action information to evaluate the applicability of forestomach cancers to human cancer risk assessment. In the present study we exposed mice to benzo(a)pyrene (BaP), an environmental carcinogen commonly associated with tumors of the rodent forestomach. Toxicogenomic tools were used to profile gene expression response in the forestomach. Adult Muta™Mouse males were orally exposed to 25, 50, and 75 mg BaP/kg-body-weight/day for 28 consecutive days. The forestomach was collected three days post-exposure. DNA microarrays, real-time RT-qPCR arrays, and protein analyses were employed to characterize responses in the forestomach. Microarray results showed altered expression of 414 genes across all treatment groups (± 1.5 fold; false discovery rate adjusted P ≤ 0.05). Significant downregulation of genes associated with phase II xenobiotic metabolism and increased expression of genes implicated in antigen processing and presentation, immune response, chemotaxis, and keratinocyte differentiation were observed in treated groups in a dose-dependent manner. A systematic comparison of the differentially expressed genes in the forestomach from the present study to differentially expressed genes identified in human diseases including human gastrointestinal tract cancers using the NextBio Human Disease Atlas showed significant commonalities between the two models. Our results provide molecular evidence supporting the use of the mouse forestomach model to evaluate chemically-induced gastrointestinal carcinogenesis in humans. - Highlights: • Benzo(a)pyrene-mediated transcriptomic response in the forestomach was examined. • The immunoproteosome subunits and MHC class I

  3. Genetic regulation of the intercellular adhesion locus in staphylococci

    Directory of Open Access Journals (Sweden)

    David R Cue

    2012-03-01

    Full Text Available The formation of biofilms by Staphylococcus aureus and Staphylococcus epidermidis is an important aspect of many staphylococcal infections, most notably endocarditis, osteomyelitis and infections associated with indwelling medical devices. The major constituents of S. aureus biofilms are polysaccharides, such as poly N-acetyl glucosamine (PIA/PNAG, cell surface and secreted bacterial proteins, and extracellular DNA. The exact composition of biofilms often varies considerably between different strains of staphylococci and between different sites of infection by the same strain. PIA/PNAG is synthesized by the products of 4 genes, icaADBC, that are encoded in a single operon. A fifth gene, icaR, is a negative regulator of icaADBC. Expression of icaADBC is tightly regulated, but can often be induced in vitro by growing staphylococci in the presence of high salt, high glucose or ethanol. Regulation of icaADBC is complex and numerous regulatory factors have been implicated in control of icaADBC. Many of these are well known global transcriptional regulatory factors like SarA and sigmaB, whereas other regulators, such as IcaR, seem to affect expression of relatively few genes. Here, we will attempt to summarize how various regulatory factors affect the production of PIA/PNAG in staphylococci.

  4. Regulation of the Host Antiviral State by Intercellular Communications

    Directory of Open Access Journals (Sweden)

    Sonia Assil

    2015-08-01

    Full Text Available Viruses usually induce a profound remodeling of host cells, including the usurpation of host machinery to support their replication and production of virions to invade new cells. Nonetheless, recognition of viruses by the host often triggers innate immune signaling, preventing viral spread and modulating the function of immune cells. It conventionally occurs through production of antiviral factors and cytokines by infected cells. Virtually all viruses have evolved mechanisms to blunt such responses. Importantly, it is becoming increasingly recognized that infected cells also transmit signals to regulate innate immunity in uninfected neighboring cells. These alternative pathways are notably mediated by vesicular secretion of various virus- and host-derived products (miRNAs, RNAs, and proteins and non-infectious viral particles. In this review, we focus on these newly-described modes of cell-to-cell communications and their impact on neighboring cell functions. The reception of these signals can have anti- and pro-viral impacts, as well as more complex effects in the host such as oncogenesis and inflammation. Therefore, these “broadcasting” functions, which might be tuned by an arms race involving selective evolution driven by either the host or the virus, constitute novel and original regulations of viral infection, either highly localized or systemic.

  5. Remodelling of cellular excitation (reaction) and intercellular coupling (diffusion) by chronic atrial fibrillation represented by a reaction-diffusion system

    Science.gov (United States)

    Zhang, Henggui; Garratt, Clifford J.; Kharche, Sanjay; Holden, Arun V.

    2009-06-01

    Human atrial tissue is an excitable system, in which myocytes are excitable elements, and cell-to-cell electrotonic interactions are via diffusive interactions of cell membrane potentials. We developed a family of excitable system models for human atrium at cellular, tissue and anatomical levels for both normal and chronic atrial fibrillation (AF) conditions. The effects of AF-induced remodelling of cell membrane ionic channels (reaction kinetics) and intercellular gap junctional coupling (diffusion) on atrial excitability, conduction of excitation waves and dynamics of re-entrant excitation waves are quantified. Both ionic channel and gap junctional coupling remodelling have rate dependent effects on atrial propagation. Membrane channel conductance remodelling allows the propagation of activity at higher rates than those sustained in normal tissue or in tissue with gap junctional remodelling alone. Membrane channel conductance remodelling is essential for the propagation of activity at rates higher than 300/min as seen in AF. Spatially heterogeneous gap junction coupling remodelling increased the risk of conduction block, an essential factor for the genesis of re-entry. In 2D and 3D anatomical models, the dynamical behaviours of re-entrant excitation waves are also altered by membrane channel modelling. This study provides insights to understand the pro-arrhythmic effects of AF-induced reaction and diffusion remodelling in atrial tissue.

  6. Intercellular pectic protuberances in Hymenaea stigonocarpa (Fabaceae, Caesalpinioideae): occurrence and functional aspects.

    Science.gov (United States)

    Paiva, Elder Antônio Sousa; Machado, Sílvia Rodrigues

    2008-04-01

    A study of the anatomy and ultrastructural aspects of leaf mesophyll and floral nectaries of Hymenaea stigonocarpa Mart. ex Hayne revealed the presence of intercellular pectic protuberances (IPPs) linking adjacent cells in both the leaf palisade cells and the secretory parenchyma of the floral nectary. Samples of the middle third of the leaf blade and of floral nectaries in anthesis were collected, fixed, and processed using standard procedures for light, transmission, and scanning electron microscopies. The IPPs of palisade cells of the mesophyll and the secretory parenchyma cells of the floral nectary take the form of scalae or strands, respectively. No evidence of the specific synthesis of these structures was observed, and they are apparently formed by the separation of adjacent cells due to cell expansion, when intercellular spaces develop. The IPPs observed in H. stigonocarpa increase cellular contact and probably act in apoplastic transport.

  7. Intercellular communication patterns are involved in cell determination in early molluscan development.

    Science.gov (United States)

    de Laat, S W; Tertoolen, L G; Dorresteijn, A W; van den Biggelaar, J A

    1980-10-01

    The formation of specialized intercellular junctions, allowing the passage of low-molecular weight regulatory molecules, has been considered as a possible mechanism for regulating embryonic development. No direct evidence for this concept has been found in early development. In the mollusc Pattella vulgata it was demonstrated that cell positioning and specific cellular interactions are key factors in the control of early development. We have now investigated the pattern of intercellular communication during early development of this embryo by intracellular iontophoresis of the fluorescent dye Lucifer Yellow CH. We demonstrate that the formation of regional- and temporal-specific cell-to-cell coupling is correlated with the determination of the mesentoblast--the stem cell of the mesoderm--and the establishment of dorso-ventral polarity. PMID:7422006

  8. Intercellular communication of notochord cells during their differentiation in Cynops orientalis

    Institute of Scientific and Technical Information of China (English)

    ZENGMIBAI; YINGWANG; 等

    1993-01-01

    Intercellular communication of notochord cells during their differentiation was studied by microinjection of a fluorescent dye.Lucifer Yellow,Close correlation existed between the incidences of dye coupling and quantitative evaluation of gap junctions.high incidences of dye coupling and of gap junctions occurred at a stage when notochord cells were active in the change of cell shape and cell arrangement.With the subsidence of cell movements,both dye coupling and gap junctions were reduced to lower levels.It was,therefore,Suggested that intercellular communication via gap junctions played an important role in the coordination of notochord cell movements.Gap Junctions of altered configuration occurred in notochord cells in late taibud stage.The comparison of incidences of dye coupling at this stage with those at other stages strongly suggested that the gap junctions of altered configuration functioned just as those of generalized type.

  9. USE OF MULTIPHOTON LASER SCANNING MICROSCOPY TO IMAGE BENZO[A]PYRENE AND METABOLITES IN FISH EGGS

    Science.gov (United States)

    Multiphoton laser scanning microscopy (MPLSM) is a promising tool to study the tissue distribution of environmental chemical contaminants during fish early life stages. One such chemical for which this is possible is benzo[a]pyrene (BaP), a polycyclic aromatic hydrocarbon that a...

  10. Effects on specific promoter DNA methylation in zebrafish embryos and larvae following benzo[a]pyrene exposure

    Science.gov (United States)

    Benzo[a]pyrene (BaP) is an established reproductive and developmental toxicant. BaP exposure in humans and animals has been linked to infertility and multigenerational health consequences. DNA methylation is the most studied epigenetic mechanism that regulates gene expression, and mapping of methyla...

  11. USE OF MULTIPHOTON LASER SCANNING MICROSCOPY TO IMAGE BENZO[A]PYRENE AND METABOLITES IN FISH EARLY LIFE STAGES

    Science.gov (United States)

    Multiphoton laser scanning micrsocopy holds promise as a tool to study the tissue distribution of environmental chemical contaminants during fish early life stage development. One such chemical for which this is possible is benzo[a]pyrene (BaP), a polyaromatic hydrocarbon that a...

  12. Effects of Benzo[a]pyrene on DNA Damage and Histological alterations in Gonad of Scallop Chlamys farreri

    OpenAIRE

    Jing-Jing, Miao; Lu-Qing, Pan; Jing, Liu; Lin, Zhang

    2008-01-01

    Effects of Benzo[a]pyrene on DNA Damage and Histological alterations in Gonad of Scallop Chlamys farreri correspondence: Corresponding author. (Lu-qing, Pan) (Lu-qing, Pan) The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China - No. 5--> , Yushan Road--> , Qingdao--> - CHINA (Jing-jing, Miao) The Key Laboratory of Mariculture, Ministry of Education, Ocean University ...

  13. Association of Intercellular Adhesion Molecule 1 (ICAM1) with Diabetes and Diabetic Nephropathy

    OpenAIRE

    Gu, Harvest F; Jun eMa; Gu, Karolin T.; Kerstin eBrismar

    2013-01-01

    Diabetes and diabetic nephropathy are complex diseases affected by genetic and environmental factors. Identification of the susceptibility genes and investigation of their roles may provide useful information for better understanding of the pathogenesis and for developing novel therapeutic approaches. Intercellular adhesion molecule 1 (ICAM1) is a cell surface glycoprotein expressed on endothelial cells and leukocytes in the immune system. The ICAM1 gene is located on chromosome 19p13 within ...

  14. Circadian and seasonal variations in pineal gland intercellular canaliculi in the white rat

    OpenAIRE

    Martínez Soriano, F.; Cimas García, C.; Ruíz Torner, A.

    1991-01-01

    Seventy Wistar rats are used to study the changes in pineal intercellular canaliculi over a 21-hour period and for two different photoperiods (pre-autumn, first week of September, and winter, first week of February). The study considers these changes at pineal body, cortical and medullar level separately, and compares the values obtained. The results show variations in canalicular surface at different point times (10:00, 14:00,18:00) and for both photoperiods. ...

  15. Kinetic Measurements Reveal Enhanced Protein-Protein Interactions at Intercellular Junctions.

    Science.gov (United States)

    Shashikanth, Nitesh; Kisting, Meridith A; Leckband, Deborah E

    2016-01-01

    The binding properties of adhesion proteins are typically quantified from measurements with soluble fragments, under conditions that differ radically from the confined microenvironment of membrane bound proteins in adhesion zones. Using classical cadherin as a model adhesion protein, we tested the postulate that confinement within quasi two-dimensional intercellular gaps exposes weak protein interactions that are not detected in solution binding assays. Micropipette-based measurements of cadherin-mediated, cell-cell binding kinetics identified a unique kinetic signature that reflects both adhesive (trans) bonds between cadherins on opposing cells and lateral (cis) interactions between cadherins on the same cell. In solution, proposed lateral interactions were not detected, even at high cadherin concentrations. Mutations postulated to disrupt lateral cadherin association altered the kinetic signatures, but did not affect the adhesive (trans) binding affinity. Perturbed kinetics further coincided with altered cadherin distributions at junctions, wound healing dynamics, and paracellular permeability. Intercellular binding kinetics thus revealed cadherin interactions that occur within confined, intermembrane gaps but not in solution. Findings further demonstrate the impact of these revealed interactions on the organization and function of intercellular junctions. PMID:27009566

  16. Nanodiamond-Mediated Intercellular Transport of Proteins through Membrane Tunneling Nanotubes.

    Science.gov (United States)

    Epperla, Chandra Prakash; Mohan, Nitin; Chang, Che-Wei; Chen, Chia-Chun; Chang, Huan-Cheng

    2015-12-01

    Recently discovered tunneling nanotubes (TNTs) are capable of creating intercellular communication pathways through which transport of proteins and other cytoplasmic components occurs. Intercellular transport is related to many diseases and nanotubes are potentially useful as drug-delivery channels for cancer therapy. Here, we apply fluorescent nanodiamond (FND) as a photostable tracker, as well as a protein carrier, to illustrate the transport events in TNTs of human cells. Proteins, including bovine serum albumin and green fluorescent protein, are first coated on 100-nm FNDs by physical adsorption and then single-particle tracking of the bioconjugates in the transient membrane connections is carried out by fluorescence microscopy. Stop-and-go and to-and-fro motions mediated by molecular motors are found for the active transport of protein-loaded FNDs trapped in the endosomal vehicles of human embryonic kidney cells (HEK293T). Quantitative analysis of the heterotypical transport between HEK293T and SH-SY5Y neuroblastoma cells by flow cytometry confirm the formation of open-ended nanotubes between them, despite that their TNTs differ in structural components. Our results demonstrate the promising applications of this novel carbon-based nanomaterial for intercellular delivery of biomolecular cargo down to the single-particle level.

  17. Impact of Gap Junctional Intercellular Communication on MLO-Y4 Sclerostin and Soluble Factor Expression.

    Science.gov (United States)

    York, S L; Sethu, P; Saunders, M M

    2016-04-01

    Bone remodeling is a continual process in which old bone is resorbed by osteoclasts and new bone is formed by osteoblasts, providing a mechanism for bones' ability to adapt to changes in its mechanical environment. While the role of osteoblasts and osteoclasts in bone remodeling is well understood, the cellular regulation of bone remodeling is unclear. One theory is that osteocytes, found within bone, play an important role in controlling the bone remodeling response. Osteocytes possess gap junctions, narrow channels that extend between nearby cells and allow communication between cells via the transfer of small molecules and ions. This work investigated the potential role of gap junctional intercellular communication in bone remodeling by exposing osteocyte-like MLO-Y4 cells to mechanical strains and quantifying the expression of soluble factors, including sclerostin, a protein closely associated with bone remodeling. The soluble factors and sclerostin expression were further examined after inhibiting gap junctional intercellular communication to study the impact of the communication. At supraphysiologic strains, the inhibition of gap junctional intercellular communication led to increases in sclerostin expression relative to cells in which communication was present, indicating that the communication may play a significant role in regulating bone remodeling. PMID:26154422

  18. Intercellular HOCl-mediated Apoptosis Induction in Malignant Cells: Interplay Between NOX1-Dependent Superoxide Anion Generation and DUOX-related HOCl-generating Peroxidase Activity.

    Science.gov (United States)

    Pottgiesser, Stefanie J; Heinzelmann, Sonja; Bauer, Georg

    2015-11-01

    Intercellular apoptosis-inducing HOCl signaling is discussed as a control step during oncogenesis. It is defined as a sophisticated interplay between transformed target cells and non-transformed or transformed effector cells. In this study, transformed target cells were seeded as clumps of high local cell density, but low total cell number. They were surrounded by large numbers of effector cells, seeded at low local density. This spatially defined experimental arrangement allowed study of the impact of siRNA-mediated knockdown of NADPH oxidase 1 (NOX1) or dual oxidase 1 (DUOX1) on intercellular HOCl signaling. Our data show that the target function of transformed cells is defined as expression of NOX1 and subsequent extracellular superoxide anion generation. The NOX domain of DUOX1 does not contribute to the target function. The peroxidase domain of DUOX1 is released from transforming growth factor β1-treated non-transformed and transformed cells and acts in trans as HOCl-synthesizing peroxidase. These findings clarify the biochemical source of HOCl during HOCl-mediated signaling. PMID:26504017

  19. Direct and indirect inactivation of tumor cell protective catalase by salicylic acid and anthocyanidins reactivates intercellular ROS signaling and allows for synergistic effects.

    Science.gov (United States)

    Scheit, Katrin; Bauer, Georg

    2015-03-01

    Salicylic acid and anthocyanidins are known as plant-derived antioxidants, but also can provoke paradoxically seeming prooxidant effects in vitro. These prooxidant effects are connected to the potential of salicylic acid and anthocyanidins to induce apoptosis selectively in tumor cells in vitro and to inhibit tumor growth in animal models. Several epidemiological studies have shown that salicylic acid and its prodrug acetylsalicylic acid are tumor-preventive for humans. The mechanism of salicylic acid- and anthocyanidin-dependent antitumor effects has remained enigmatic so far. Extracellular apoptosis-inducing reactive oxygen species signaling through the NO/peroxynitrite and the HOCl signaling pathway specifically induces apoptosis in transformed cells. Tumor cells have acquired resistance against intercellular reactive oxygen species signaling through expression of membrane-associated catalase. Here, we show that salicylic acid and anthocyanidins inactivate tumor cell protective catalase and thus reactive apoptosis-inducing intercellular reactive oxygen species signaling of tumor cells and the mitochondrial pathway of apoptosis Salicylic acid inhibits catalase directly through its potential to transform compound I of catalase into the inactive compound II. In contrast, anthocyanidins provoke a complex mechanism for catalase inactivation that is initiated by anthocyanidin-mediated inhibition of NO dioxygenase. This allows the formation of extracellular singlet oxygen through the reaction between H(2)O(2) and peroxynitrite, amplification through a caspase8-dependent step and subsequent singlet oxygen-mediated inactivation of catalase. The combination of salicylic acid and anthocyanidins allows for a remarkable synergistic effect in apoptosis induction. This effect may be potentially useful to elaborate novel therapeutic approaches and crucial for the interpretation of epidemiological results related to the antitumor effects of secondary plant compounds.

  20. Intercellular adhesion molecule 1 serves as a primary cognate receptor for the Type IV pilus of nontypeable Haemophilus influenzae.

    Science.gov (United States)

    Novotny, Laura A; Bakaletz, Lauren O

    2016-08-01

    Nontypeable Haemophilus influenzae (NTHI) utilizes the Type IV pilus (Tfp) to adhere to respiratory tract epithelial cells thus colonizing its human host; however, the host cell receptor to which this adhesive protein binds is unknown. From a panel of receptors engaged by Tfp expressed by other bacterial species, we showed that the majority subunit of NTHI Tfp, PilA, bound to intercellular adhesion molecule 1 (ICAM1) and that this interaction was both specific and of high affinity. Further, Tfp-expressing NTHI inoculated on to polarized respiratory tract epithelial cells that expressed ICAM1 were significantly more adherent compared to Tfp-deficient NTHI or NTHI inoculated on to epithelial cells to which ICAM1 gene expression was silenced. Moreover, pre-incubation of epithelial cells with recombinant soluble PilA (rsPilA) blocked adherence of NTHI, an outcome that was abrogated by admixing rsPilA with ICAM1 prior to application on to the target cells. Epithelial cells infected with adenovirus or respiratory syncytial virus showed increased expression of ICAM1; this outcome supported augmented adherence of Tfp-expressing NTHI. Collectively, these data revealed the cognate receptor for NTHI Tfp as ICAM1 and promote continued development of a Tfp-targeted vaccine for NTHI-induced diseases of the airway wherein upper respiratory tract viruses play a key predisposing role.

  1. Liquid chromatographic determination of benzo(a)pyrene in total particulate matter of cigarette smoke

    Energy Technology Data Exchange (ETDEWEB)

    Tomkins, B.A.; Jenkins, R.A.; Griest, W.H.; Reagan, R.R.; Holladay, S.K.

    1985-09-01

    The benzo(a)pyrene (BaP) delivery of reference and commercially available tobacco cigarettes, as well as reference and placebo marijuana cigarettes, is determined using a sequential liquid chromatographic/liquid chromatographic procedure. The total particulate matter of sample cigarette smoke is collected using a Cambridge filter pad, which is ultrasonically extracted with acetone. The resulting extract is filtered, then fractionated using semipreparative-scale normal phase liquid chromatography (LC). Quantitative determination is achieved using analytical-scale reverse phase LC equipped with a fluorescence detector. The method is precise (+/- 10-15% relative standard deviation) and yields 85% or better BaP recovery at the ng/cig. level. A single pad may be analyzed in 8 person-hours, while a more typical lot of 12 pads (6 pads each for 2 cigarette brands) may be analyzed in 10 person-days.

  2. Bioremediation of phenanthrene, chrysene and benzo[a]pyrene by fungi screened from nature

    Directory of Open Access Journals (Sweden)

    Tony Hadibarata

    2009-09-01

    Full Text Available Laccase of Polyporus sp. S133 was able to oxidize most of the 3 different rings amount polycyclic aromatic hydrocarbons (PAHs tested. Phenanthrene was removed by 89% followed by chrysene and benzo[a]pyrene which were oxidized by 66 and 55%, respectively. Addition of 1-hydroxybenzotriazole (HBT to the reaction mixture increased oxidation of PAHs, especially phenanthrene was almost completely removed from the reaction mixture. Oxidation of chrysene and benzo[a]anthracene increased 12 and 10% with the mediator to 78 and 65% in the presence of HBT. PAH-quinones as oxidation products were formed from all PAH to different extents. A part of PAH was polymerized in the laccase/mediator system to products of weight-average molecular weight (MW. The correlation of the ionization potentials of PAH with the oxidation of these compounds is limited to the alternating PAH.

  3. Antibodies to benzo(a)pyrene and their use in immunoassays

    Energy Technology Data Exchange (ETDEWEB)

    Murchison, C.M.

    1984-12-10

    Antibodies to benzo(a)pyrene were produced by coupling the carcinogen to bovine serum albumin and immunizing New Zealand white rabbits and Fischer rats with the conjugate. Sera was collected from blood samples and assayed to determine antibody titer using the following procedures: Ouchterlony double diffusion, passive hemagglutination, and an enzyme immunoassay (EIA). Results showed significant antibody titer, the highest found in samples taken from our subcutaneously injected rabbit. Sera from this rabbit showed a titer of 1/256 in the hemagglutination assay and a titer of 1/15,625 in the EIA. Isolated specific antibodies will be used in the development of fluoroimmuno sensor. 21 references, 4 figures, 3 tables.

  4. Predicting lung dosimetry of inhaled particleborne benzo[a]pyrene using physiologically based pharmacokinetic modeling

    Science.gov (United States)

    Campbell, Jerry; Franzen, Allison; Van Landingham, Cynthia; Lumpkin, Michael; Crowell, Susan; Meredith, Clive; Loccisano, Anne; Gentry, Robinan; Clewell, Harvey

    2016-01-01

    Abstract Benzo[a]pyrene (BaP) is a by-product of incomplete combustion of fossil fuels and plant/wood products, including tobacco. A physiologically based pharmacokinetic (PBPK) model for BaP for the rat was extended to simulate inhalation exposures to BaP in rats and humans including particle deposition and dissolution of absorbed BaP and renal elimination of 3-hydroxy benzo[a]pyrene (3-OH BaP) in humans. The clearance of particle-associated BaP from lung based on existing data in rats and dogs suggest that the process is bi-phasic. An initial rapid clearance was represented by BaP released from particles followed by a slower first-order clearance that follows particle kinetics. Parameter values for BaP-particle dissociation were estimated using inhalation data from isolated/ventilated/perfused rat lungs and optimized in the extended inhalation model using available rat data. Simulations of acute inhalation exposures in rats identified specific data needs including systemic elimination of BaP metabolites, diffusion-limited transfer rates of BaP from lung tissue to blood and the quantitative role of macrophage-mediated and ciliated clearance mechanisms. The updated BaP model provides very good prediction of the urinary 3-OH BaP concentrations and the relative difference between measured 3-OH BaP in nonsmokers versus smokers. This PBPK model for inhaled BaP is a preliminary tool for quantifying lung BaP dosimetry in rat and humans and was used to prioritize data needs that would provide significant model refinement and robust internal dosimetry capabilities. PMID:27569524

  5. In vitro Study on Role of Hsp70 Expression in DNA Damage of Human Embryonic Lung Cells Exposed to Benzo[a]pyrene

    Institute of Scientific and Technical Information of China (English)

    YA-JUAN GAO; CHENG-FENG XIAO; SHENG CHEN; RUI-BO WANG; HAN-ZHEN HE; ROBERT M TANGUAY; TANG-CHUN WU

    2004-01-01

    Objective Benzo[a]pyrene (B[a]P), a ubiquitous environmental pollutant, is a potent procarcinogen and mutagen that can elicit tumors, leading to malignancy. Heat shock proteins (Hsp) have been shown to protect cells against damages caused by various stresses including exposure to numerous chemicals. Whether Hsps, or more specifically Hsp70, are involved in repair of B[a]P-induced DNA damage is currently unknown. Methods We assessed the potential role of the inducible form of Hsp70 in B[a]P-induced DNA damage of human embryonic lung (HEL) cells using immunoblot and the comet assay (i.e., the single cell gel electrophoresis assay). Results Exposure to B[a]P induced a dose-dependent decrease in the level of Hsp70, but a dose-dependent increase in DNA damage both in untreated (control) HEL cells and in cells preconditioned by a heat treatment. Heat preconditioning prior to B[a]P exposure potentiated the effect of B[a]P at a low dose (10 (mol/L), but appeared to be protective at higher doses. There was a negative correlation between Hsp70 level and DNA damage in the non-preheated as well as in the preconditioned cells. Conclusion These data suggest that exposure of HEL cells to B[a]P may induce a dose-dependent reduction in the levels of the inducible Hsp70. The detailed mechanisms for the reduction of Hsp70 levels by B[a]P and the role of Hsp70 in DNA damage under different concentrations of B[a]P remains to be determined.

  6. Measurement of human CYP1A2 induction by inhalation exposure to benzo(a)pyrene based on in vivo isotope breath method.

    Science.gov (United States)

    Duan, Xiaoli; Shen, Guofeng; Yang, Hongbiao; Lambert, George; Wei, Fusheng; Zhang, Junfeng Jim

    2016-01-01

    Cytochrome P450 1A2 (CYP1A2) is an enzyme involved in the metabolic activation of certain carcinogens, and inducible by toxic substrates. To date, few studies have investigated in vivo CYP1A2 induction in humans and its relationship to polycylic aromatic hydrocarbons (PAHs) like benzo(a)pyrene (BaP). Non-smoking healthy male coke-oven workers (n = 30) were recruited as 'exposure' group, and non-smoking healthy office workers in the same city (n = 10) were selected as 'control' group, to test whether high inhalation exposure to PAHs can induce CYP1A2 activity in human livers. Significantly higher inhalation exposure of PAHs were found among the exposure group compared to the control. Inhalation BaP exposure concentration in the exposure group was more than 30 times higher than the control group (p < 0.001). However, the exposure group did not exhale significant higher levels of (13)CO2/(12)CO2 in breath samples (p = 0.81), and no significant relationship was found between the inhaled BaP concentration and the (13)CO2/(12)CO2 ratio (p = 0.91). A significant association was found between the (13)CO2/(12)CO2 exhalation and dietary BaP intake level. Hepatic CYP1A2 activity/induction level was not effected by inhaled BaP but was altered by ingestion of BaP. PMID:26552516

  7. The expressions of protooncogenes and CYP1A in lungs of rats exposed to sulfur dioxide and benzo(a)pyrene.

    Science.gov (United States)

    Qin, Guohua; Meng, Ziqiang

    2006-06-01

    Sulfur dioxide (SO2) is a ubiquitous air pollutant, present in low concentrations in the urban air, and in higher concentrations in the working environment. Benzo(a)pyrene (B(a)P), a polycyclic aromatic hydrocarbon, is a ubiquitous environmental contaminant with diverse toxicological effects. To investigate the interactions between SO2 and B(a)P, male Wistar rats were exposed to intratracheally instilled with benzo(a)pyrene (B(a)P; 3 mg) or SO2 (20 ppm) inhalation alone or together. The mRNA of CYP1A1 and 1A2, c-fos, and c-jun and protein levels of c-fos and c-jun were analyzed in lungs using a real-time reverse transcription-polymerase chain reaction (real-time RT-PCR) assay and Western blot analysis, respectively. And 7-ethoxyresorufin O-deethylase (EROD) and methoxyresorufin O-demethylase (MROD) activities were detected. In lungs of rats exposed to SO2 alone, the gene transcription of CYP1A1 and 1A2, the EROD and MROD activities were decreased. Meanwhile, the mRNA and protein levels of c-jun and c-fos were increased significantly. Exposure to B(a)P alone induced CYP1A1, CYP1A2 mRNA levels, the protein levels of c-jun, and the EROD and MROD activities in lungs. However, exposure to B(a)P plus inhaled SO2 neither increased nor decreased CYP1A1/2 mRNA expressions, EROD, and MROD activities in lungs, versus exposure to B(a)P alone. Nevertheless, exposure to B(a)P plus inhaled SO2 increased the mRNA and protein levels of c-jun and c-fos in lungs compared with lungs exposed to SO2 alone. Accordingly, the SO2-induced decreases of CYP1A1/2 might not influence the metabolic activation of B(a)P. However, when B(a)P and SO2 were given in the combinations, one might postulate that a synergistic effect on the expressions of c-fos and c-jun between SO2 and B(a)P, which might be one of the possible mechanisms of combination effects between B(a)P and the air pollutants.

  8. Intercellular interactions and progression of hormonal resistance of breast cancer cells

    Directory of Open Access Journals (Sweden)

    S. E. Semina

    2015-01-01

    Full Text Available The main goal of the study is the analysis of the role of cell-cell interactions in the formation of the tumor cell resistance to hormonal drugs. About 70 % of breast tumors contain estrogen receptor (ER, a key molecular target for hormone (endocrine therapy. However, the efficiency of endocrine therapy of breast cancer is limited by the development of hormone resistance which leads to progression of tumor cells to hormone-independent phenotype, increase in tumor malignancy and worse prognosis. Hormonal independence may be accompanied with the loss of the receptors, as well as with the another mechanisms including ligand-independent receptor activation, disbalance between receptor activators and repressors, stimulation of hormone-independent pathways. It is less known about the role of the intercellular interactions in the progression of hormonal resistance. Several studies demonstrate the involvement of cell junctions in the mediating of cell response to (anti estrogens, however the significance of cell-cell contacts in the formation of hormonal resistance still not clear. Here we have hypothesized that the formation of the hormone resistance of tumors may be based, at least in part, on the transferring of the resistant phenotype from the resistant to hormone-sensitive cells – as a result of the secretion of the specific factors acting in the paracrine manner or via the direct cell-cell contacts. Using the estrogen-dependent breast cancer cells MCF-7 and the resistant subline MCF-7 / T developed by long-term cultivation of MCF-7 cells in the presence of antiestrogen tamoxifen, we investigated the possible changes in the hormonal sensitivity of these cells caused by the co-cultivation in vitro. To discern the cell cultures, the MCF-7 / T cells were previously transfected with the plasmid containing the gene of the green fluorescent protein (GFP, and GFP-positive hormone-resistant subline MCF-7 / T / GFP+ was developed. We showed that the co

  9. Soluble intercellular adhesion molecule-1 as an early detection marker for radiation pneumonitis

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Y.; Kitamura, S. [Jichi Medical School, Dept. of Pulmonary Medicine, Tochigi (Japan)

    1999-04-01

    To investigate the role of intercellular adhesion molecule-1 (ICAM-1) in the pathogenesis of radiation pneumonitis and to determine whether the measurement of soluble ICAM-1 (sICAM-1) levels is useful for predicting the onset of pneumonitis, the levels of sICAM-1 were measured in serum and broncholveolar lavage (BAL) fluids from patients with lung malignancy who received radiotherapy. A total of 30 patients were irradiated with a total dose of {approx}60 Gy. Blood samples were taken before, midway and after radiotherapy. BAL was also performed before and after radiotherapy in seven cases. The sICAM-1 concentration was measured using an enzyme-linked immunosorbent assay kit with two different monoclonal antibodies. Twelve out of 30 cases developed radiation pneumonitis (pneumonitis group), and the other cases did not (non-pneumonitis group). Serum levels of sICAM-1 after radiotherapy were significantly elevated in the pneumonitis group, but not in the non-pneumonitis group. In some of the cases in the pneumonitis group, sICAM-1 levels began to increase at an early phase of irradiation. In one case of pneumonitis in which BAL was performed, the total cell count and the number of lymphocytes increased markedly, as did the level of sICAM-1 in BAL fluid. These findings suggest that intercellular adhesion molecule-1 may play an important role in the development of radiation pneumonitis and that soluble intercellular adhesion molecule-1 may be a useful marker for the early detection of radiation pneumonitis. (au) 29 refs.

  10. Soluble intercellular adhesion molecule-1 for stable and acute phases of idiopathic pulmonary fibrosis

    OpenAIRE

    Okuda, Ryo; Matsushima, Hidekazu; Aoshiba, Kazutetsu; Oba, Tomohiro; Kawabe, Rie; Honda, Koujiro; Amano, Masako

    2015-01-01

    The levels of soluble intercellular adhesion molecule-1 (sICAM-1) have been reported to increase in patients with idiopathic pulmonary fibrosis. However, the utility of sICAM-1 has not been reported in detail. The aim of this study was to investigate whether sICAM-1 was a useful biomarker for stable idiopathic pulmonary fibrosis (IPF) and early phase of acute exacerbation of IPF. The patients who were diagnosed with IPF between 2013 and 2015 were enrolled. The levels of sICAM-1 and other inte...

  11. The lateral intercellular space as osmotic coupling compartment in isotonic transport

    DEFF Research Database (Denmark)

    Larsen, E.H.; Willumsen, N.J.; Mobjerg, N.;

    2009-01-01

    coupling of water absorption to ion flow is energized by lateral Na+/K+ pumps. We show that the theory accounts quantitatively for steady- and time dependent states of solute-coupled fluid uptake by toad skin epithelium. Our experimental results exclude definitively three alternative theories of epithelial...... hypertonic relative to the fluid in the lateral intercellular space. In the Na+ recirculation theory the 'surplus of solutes' is returned to the lateral space via the cells energized by the lateral Na+/K+ pumps. We show that this theory accounts quantitatively for isotonic and hypotonic transport...

  12. Computing the threshold of the influence of intercellular nanotubes on cell-to-cell communication integrity

    Science.gov (United States)

    Mihailović, Dragutin T.; Kostić, Vladimir R.; Balaž, Igor; Kapor, Darko

    2016-10-01

    We examine the threshold of the influence of the tunneling nanotubes (TNTs) on the cell-to-cell communication integrity. A deterministic model is introduced with the Michaelis-Menten dynamics and the intercellular exchange of substance. The influence of TNTs are considered as a functional perturbation of the main communication and treated as the matrix nearness problems. We analyze communication integrity in terms of the \\emph{pseudospectra} of the exchange, to find the \\emph{distance to instability}. The threshold of TNTs influence is computed for Newman-Gastner and Erd\\H{o}s-R\\'enyi gap junction (GJ) networks.

  13. Intercellular Adhesion Molecule 1 Promotes HIV-1 Attachment but Not Fusion to Target Cells

    OpenAIRE

    Naoyuki Kondo; Melikyan, Gregory B.

    2012-01-01

    Incorporation of intercellular adhesion molecule 1 (ICAM-1) into HIV-1 particles is known to markedly enhance the virus binding and infection of cells expressing lymphocyte function-associated antigen-1 (LFA-1). At the same time, ICAM-1 has been reported to exert a less pronounced effect on HIV-1 fusion with lymphoid cells. Here we examined the role of ICAM-1/LFA-1 interactions in productive HIV-1 entry into lymphoid cells using a direct virus-cell fusion assay. ICAM-1 promoted HIV-1 attachme...

  14. Inhibition of intercellular communication by condensates of high and low tar cigarettes

    DEFF Research Database (Denmark)

    Vang, Ole; Wallin, Håkan; Autrup, Herman

    1995-01-01

    Inhibition of gap junctional intercellular communication (GJIC) is a predictive short term test for tumor promoting activity. A new metabolic cooperation assay has been developed, which takes the cytochrome P-450 metabolism into account. In this assay the inhibitory activity of tobacco smoke...... condensates (CSC) and CSC fractions from high and low tar cigarettes was tested. CSC of both high and low tar cigarettes and fractions thereof contained tumor promoting activity. The tar yield of the cigarettes did not closely reflect the effects in the GJIC assay and the major constituent nicotine had...

  15. Coupling vs decoupling approaches for PDE/ODE systems modeling intercellular signaling

    Science.gov (United States)

    Carraro, Thomas; Friedmann, Elfriede; Gerecht, Daniel

    2016-06-01

    We consider PDE/ODE systems for the simulation of intercellular signaling in multicellular environments. The intracellular processes for each cell described here by ODEs determine the long-time dynamics, but the PDE part dominates the solving effort. Thus, it is not clear if commonly used decoupling methods can outperform a coupling approach. Based on a sensitivity analysis, we present a systematic comparison between coupling and decoupling approaches for this class of problems and show numerical results. For biologically relevant configurations of the model, our quantitative study shows that a coupling approach performs much better than a decoupling one.

  16. Hasse diagram as a green analytical metrics tool: ranking of methods for benzo[a]pyrene determination in sediments.

    Science.gov (United States)

    Bigus, Paulina; Tsakovski, Stefan; Simeonov, Vasil; Namieśnik, Jacek; Tobiszewski, Marek

    2016-05-01

    This study presents an application of the Hasse diagram technique (HDT) as the assessment tool to select the most appropriate analytical procedures according to their greenness or the best analytical performance. The dataset consists of analytical procedures for benzo[a]pyrene determination in sediment samples, which were described by 11 variables concerning their greenness and analytical performance. Two analyses with the HDT were performed-the first one with metrological variables and the second one with "green" variables as input data. Both HDT analyses ranked different analytical procedures as the most valuable, suggesting that green analytical chemistry is not in accordance with metrology when benzo[a]pyrene in sediment samples is determined. The HDT can be used as a good decision support tool to choose the proper analytical procedure concerning green analytical chemistry principles and analytical performance merits.

  17. Cassia senna inhibits mutagenic activities of benzo[a]-pyrene, aflatoxin B1, shamma and methyl methanesulfonate.

    Science.gov (United States)

    al-Dakan, A A; al-Tuffail, M; Hannan, M A

    1995-10-01

    Ethanol extract of Senokot tablets (Cassia senna concentrate used as vegetable laxative), was found to be non-mutagenic while it inhibited the mutagenicity of benzo[a]pyrene, shamma, aflatoxin B1 and methyl methanesulfonate in the Ames histidine reversion assay using the Salmonella typhimurium tester strain TA98. While the Senokot extract completely inhibited the mutagenicity of promutagens (i.e. metabolic activation dependent) like benzo[a]pyrene and shamma, it reduced the mutagenic activity of the direct acting mutagen methyl methanesulfonate by only 58%. The mutagen aflatoxin B1 showed a 25-fold increase in the number of histidine revertants per plate at low concentrations (1.0-4.0 micrograms/plate) in the presence of metabolic activation system while at high concentrations (10.0-30.0 micrograms/plate) it proved to be weakly mutagenic (with a 5-fold increase in the number of histidine revertants/plate) without metabolic activation. The Senokot extract completely inhibited the mutagenic effect of low concentrations of aflatoxin B1 in the presence of metabolic activation but not that resulting from higher concentrations without metabolic activation. The results obtained with benzo[a]pyrene, shamma and aflatoxin B1 indicated that the antimutagenic effects of Senokot extract could be largely due to an interaction with the metabolic process involved in the activation of procarcinogens. However, the results obtained with methyl methanesulfonate suggested that factors in Senokot may also interact with direct mutagens to produce some antimutagenic effects. An ethanol extract of crude senna leaves found to be weakly mutagenic also inhibited (though less than Senokot) the mutagenic effect of benzo[a]pyrene suggesting that the antimutagenic principle is present in the complex plant material itself.

  18. Seasonal trends of benzo(a)pyrene in suspended particulate matter in urban areas of Belgrade, Serbia

    OpenAIRE

    Snežana Matić-Besarabić; Ljiljana Adjanski-Spasić; Milena Jovašević-Stojanović; Anka Cvetković; Dragan A. Marković

    2010-01-01

    Polycyclic aromatic hydrocarbons (PAHs) were identified to be one of the major toxic air pollutants in urban environment. PAHs are mostly formed during incomplete combustion or pyrolysis of organic material. According to Serbian National Legislation, benzo(a)pyrene (BaP) concentration in total suspended particles (TSP) in ambient air in the Belgrade metropolitan area has been determined in the last ten years, as a part of a local air pollution monitoring program performed by the Public Health...

  19. Does the Digestibility of Cyclodextrins Influence the In Vivo Absorption of Benzo[a]pyrene in Rats?

    Science.gov (United States)

    Olesen, Niels E; Vana, Vasiliki; Holm, René

    2016-09-01

    An important excipient used to overcome poor solubility is cyclodextrin. However, data in the literature suggest that excessive overdosing of cyclodextrins can decrease the absorption of compounds administered with cyclodextrins, due to their lack of release from the complex. γ-Cyclodextrin is digestible in contrast to β-cyclodextrins. This could potentially limit the sensitivity toward overdose, which was evaluated using benzo[a]pyrene in this study, in which rats were administered benzo[a]pyrene and different doses of the 2 cyclodextrins. Both cyclodextrins lowered the area under the curve and therefore the absorption of benzo[a]pyrene by up to a factor of 2 when dosed in high concentrations, thus indicating that overdosing of cyclodextrins may limit the oral absorption of a compound. This limitation may be artificial because the molar ratio of benzo[a]pyrene:cyclodextrin was >1:50,000 at the concentration where a significant decrease in the absorption was observed. No difference was observed between the 2 cyclodextrins, so digestibility seemed less important. More interesting was that the decrease in absorption was relatively small when compared with literature values, suggesting that the effect of overdosing a compound with cyclodextrins was lower than anticipated.

  20. Determination of benzo[a]pyrene and dibenzopyrenes in a Chinese coal fly ash certified reference material.

    Science.gov (United States)

    Masala, Silvia; Bergvall, Christoffer; Westerholm, Roger

    2012-08-15

    Air pollution from coal combustion is of great concern in China because coal is the country's principal source of energy and it has been estimated that coal combustion is one of the main sources of polycyclic aromatic hydrocarbon (PAH) emissions in the nation. This study reports the concentrations of 15 PAHs including benzo[a]pyrene, dibenzo[a,l]pyrene, dibenzo[a,e]pyrene, dibenzo[a,i]pyrene and dibenzo[a,h]pyrene in a coal fly ash certified reference material (CRM) from China. To the best of our knowledge, dibenzo[a,l]pyrene, dibenzo[a,i]pyrene and dibenzo[a,h]pyrene concentrations in coal fly ash particles have not previously been reported. Benzo[a]pyrene is the only one of the studied hydrocarbons whose concentration in the coal fly ash CRM had previously been certified. The concentration of this species measured in this present work was twice the certified value. This is probably because of the exhaustive accelerated solvent extraction method employed. Consecutive extractions indicated an extraction recovery in excess of 95% for benzo[a]pyrene. For the other determined PAHs, repeat extractions indicated recoveries above 90%. PMID:22728296

  1. A RelA-dependent two-tiered regulated proteolysis cascade controls synthesis of a contact-dependent intercellular signal in Myxococcus xanthus.

    Science.gov (United States)

    Konovalova, Anna; Löbach, Stephanie; Søgaard-Andersen, Lotte

    2012-04-01

    Proteolytic cleavage of precursor proteins to generate intercellular signals is a common mechanism in all cells. In Myxococcus xanthus the contact-dependent intercellular C-signal is a 17 kDa protein (p17) generated by proteolytic cleavage of the 25 kDa csgA protein (p25), and is essential for starvation-induced fruiting body formation. p25 accumulates in the outer membrane and PopC, the protease that cleaves p25, in the cytoplasm of vegetative cells. PopC is secreted in response to starvation, therefore, restricting p25 cleavage to starving cells. We focused on identifying proteins critical for PopC secretion in response to starvation. PopC secretion depends on the (p)ppGpp synthase RelA and the stringent response, and is regulated post-translationally. PopD, which is encoded in an operon with PopC, forms a soluble complex with PopC and inhibits PopC secretion whereas the integral membrane AAA+ protease FtsH(D) is required for PopC secretion. Biochemical and genetic evidence suggest that in response to starvation, RelA is activated and induces the degradation of PopD thereby releasing pre-formed PopC for secretion and that FtsH(D) is important for PopD degradation. Hence, regulated PopC secretion depends on regulated proteolysis. Accordingly, p17 synthesis depends on a proteolytic cascade including FtsH(D) -dependent degradation of PopD and PopC-dependent cleavage of p25. PMID:22404381

  2. Exploring the role of lipids in intercellular conduits: breakthroughs in the pipeline

    Directory of Open Access Journals (Sweden)

    Elise eDelage

    2013-12-01

    Full Text Available It has been known for more than a century that most of the plant cells are connected to their neighbors through membranous pores perforating the cell wall, namely plasmodesmata (PDs. The recent discovery of tunneling nanotubes (TNTs, thin membrane bridges established between distant mammalian cells, suggests that intercellular communication mediated through cytoplasmic continuity could be a conserved feature of eukaryotic organisms. Although TNTs differ from PDs in their formation and architecture, both are characterized by a continuity of the plasma membrane between two cells, delimiting a nanotubular channel supported by actin-based cytoskeleton. Due to this unusual membrane organization, lipids are likely to play critical roles in the formation and stability of intercellular conduits like TNTs and PDs, but also in regulating the transfer through these structures. While it is crucial for a better understanding of those fascinating communication highways, the study of TNT lipid composition and dynamics turned out to be extremely challenging. The present review aims to give an overview of the recent findings in this context. We will also discuss some of the promising imaging approaches, which might be the key for future breakthroughs in the field and could also benefit the research on PDs.

  3. Intercellular Trogocytosis Plays an Important Role in Modulation of Immune Responses

    Institute of Scientific and Technical Information of China (English)

    Khawaja Ashfaque Ahmed; Manjunatha Ankathatti Munegowda; Yufeng Xie; Jim Xiang

    2008-01-01

    Intercellular communication is an important means of molecular information transfer through exchange of membrane proteins from cells to cells. Advent of the latest analytical and imaging tools has allowed us to enhance our understanding of the cellular communication through the intercellular exchange of intact membrane patches, also called trogocytosis, which is a ubiquitous phenomenon. Immune responses against pathogens or any foreign antigens require fine immune regulation, where cellular communications are mediated by either soluble or cell surface molecules. It has been demonstrated that the membrane molecule transfer between immune cells such as dendritic and T cells can be derived through internalization/recycling pathway, dissociation-associated pathway, uptake of exosomes and membrane nanotube formations. Recent evidence implicates the trogocytosis as an important mechanism of the immune system to modulate immune responses. Exchange of membrane molecules/ antigens between immune cells has been observed for a long time, but the mechanisms and functional consequences of these transfers remain unclear. In this review, we discuss the possible mechanisms of trogocytosis and its physiological relevance to immune system, with special reference to T cells and the stimulatory or suppressive immune responses derived from T cells with acquired dendritic cell membrane molecules. Cellular & Molecular Immunology. 2008;5(4):261-269.

  4. Intercellular Communication by Exosome-Derived microRNAs in Cancer

    Directory of Open Access Journals (Sweden)

    Wei-Qun Ding

    2013-07-01

    Full Text Available The development of human cancers is a multistep process in which normal cells acquire characteristics that ultimately lead to their conversion into cancer cells. Many obstacles must be overcome for this process to occur; of these obstacles, is the ability to survive an inhospitable microenvironment. It is recognized that the intercommunication between tumor cells and their surrounding microenvironment is essential to overcoming this obstacle and for the tumor to progress, metastasize and establish itself at distant sites. Exosomes are membrane-derived vesicles that have recently been recognized as important mediators of intercellular communication, as they carry lipids, proteins, mRNAs and microRNAs that can be transferred to a recipient cell via fusion of the exosome with the target cell membrane. In the context of cancer cells, this process entails the transfer of cancer-promoting cellular contents to surrounding cells within the tumor microenvironment or into the circulation to act at distant sites, thereby enabling cancer progression. In this process, the transfer of exosomal microRNAs to a recipient cell where they can regulate target gene expression is of particular interest, both in understanding the basic biology of cancer progression and for the development of therapeutic approaches. This review discusses the exosome-mediated intercellular communication via microRNAs within the tumor microenvironment in human cancers, with a particular focus on breast cancer exosomes.

  5. Biochemical responses in seabream (Sparus aurata) caged in-field or exposed to benzo(a)pyrene and paraquat. Characterization of glutathione S-transferases.

    Science.gov (United States)

    Jebali, Jamel; Chicano-Gálvez, Eduardo; Banni, Mohamed; Guerbej, Hamadi; Boussetta, Hamadi; López-Barea, Juan; Alhama, José

    2013-02-01

    Gilthead seabream (Sparus aurata) specimens were caged in-field at the Téboulba harbour or exposed to benzo(a)pyrene [B(a)P] or to paraquat [PQ] plus B(a)P, and several biochemical biomarker responses were investigated. Antioxidant enzymes, such as glutathione peroxidase, catalase and glutathione reductase, significantly increased in the in-field and B(a)P+PQ exposures, but were only moderately affected by B(a)P alone. Glucose-6-phosphate and 6-phosphogluconate dehydrogenases significantly diminished after in-field exposure. Different responses with biotransformation enzymes were observed: the P4501A-associated EROD activity was highly induced in response to B(a)P and B(a)P+PQ exposures, while total activity of the glutathione S-transferase (GST) was similar to control. However, after purification of the GST proteins by affinity chromatograpy and analysis by two-dimensional electrophoresis, nineteen highly reproducible isoforms were resolved. In addition, some of reproducible isoforms showed different and specific expression patterns in response to contaminants. Thus, proteomic analysis of the purified GST subunits is a reliable tool for ecotoxicological research, useful in polluted marine ecosystem as an effective biomarker of contamination.

  6. Inhibition of the formation of benzo[a]pyrene adducts to DNA in A549 lung cells exposed to mixtures of polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Genies, Camille; Jullien, Amandine; Lefebvre, Emmanuel; Revol, Morgane; Maitre, Anne; Douki, Thierry

    2016-09-01

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants, which exhibit carcinogenic properties especially in lungs. In the present work, we studied the effect of mixtures of 12 PAHs on the A549 alveolar cells. We first assess the ability of each PAH at inducing gene expression of phase I metabolization enzymes and at generating DNA adducts. A good correlation was found between these two endpoints. We then exposed cells to either binary mixtures of the highly genotoxic benzo[a]pyrene (B[a]P) with each PAH or complex mixtures of all studied PAHs mimicking by real emissions including combustion of wood, cigarette smoke, and atmospheres of garage, silicon factory and urban environments. Compared to pure B[a]P, both types of mixtures led to reduced CYP450 activity measured by the EROD test. A similar trend was observed for the formation of DNA adducts. Surprisingly, the complex mixtures were more potent than B[a]P used at the same concentration for the induction of genes coding for CYP. Our results stress the lack of additivity of the genotoxic properties of PAH in mixtures. Interestingly, an opposite synergy in the formation of B[a]P adducts were observed previously in hepatocytes. Our data also show that measurement of the metabolic activity rather than quantification of gene expression reflects the actual bioactivation of PAHs into DNA damaging species. PMID:27196671

  7. Effects of polycyclic aromatic hydrocarbons (PAHs) on an aquatic ecosystem: acute toxicity and community-level toxic impact tests of benzo[a]pyrene using lake zooplankton community.

    Science.gov (United States)

    Ikenaka, Yoshinori; Sakamoto, Masaki; Nagata, Takamaru; Takahashi, Hirokazu; Miyabara, Yuichi; Hanazato, Takayuki; Ishizuka, Mayumi; Isobe, Tomohiko; Kim, Jun-Woo; Chang, Kwang-Hyeon

    2013-02-01

    We estimated acute toxicity of benzo[a]pyrene (B[a]P) using two cladoceran species, Ceriodaphnia reticulata and Daphnia magna, and also analyzed its impact on zooplankton community throughout an exposure experiment using small-scale mesocosms. LC(50) of B[a]P for C. reticulata and D. magna was 4.3 and 4.7 µg/l, respectively. However, individuals fed with Chlorella showed higher LC(50), 6.1 µg/l for C. reticulata and 8.0 µg/l for D. magna. In the exposure experiment, we examined the impact of B[a]P on zooplankton community using conceivable concentrations in the environment (5 and 10 µg/l) using typical zooplankton community in eutrophicated systems. Despite the residence time of B[a]P in the water column was short as recovery pattern was different among cladocerans and rotifers. Consequently, B[a]P showed insecticide-like impacts, suppressing cladoceran populations and inducing the dominance of rotifers particularly under high concentration (10 µg/l). Results have suggested that, even such short duration of B[a]P in the water body can have impact on zooplankton abundance and community structure. Since B[a]P easily precipitate to the bottom and rapidly disappears from the water body, careful monitoring and further assessment of the potential toxicity of polycyclic aromatic hydrocarbons are necessary. PMID:23358147

  8. Effects of polycyclic aromatic hydrocarbons (PAHs) on an aquatic ecosystem: acute toxicity and community-level toxic impact tests of benzo[a]pyrene using lake zooplankton community.

    Science.gov (United States)

    Ikenaka, Yoshinori; Sakamoto, Masaki; Nagata, Takamaru; Takahashi, Hirokazu; Miyabara, Yuichi; Hanazato, Takayuki; Ishizuka, Mayumi; Isobe, Tomohiko; Kim, Jun-Woo; Chang, Kwang-Hyeon

    2013-02-01

    We estimated acute toxicity of benzo[a]pyrene (B[a]P) using two cladoceran species, Ceriodaphnia reticulata and Daphnia magna, and also analyzed its impact on zooplankton community throughout an exposure experiment using small-scale mesocosms. LC(50) of B[a]P for C. reticulata and D. magna was 4.3 and 4.7 µg/l, respectively. However, individuals fed with Chlorella showed higher LC(50), 6.1 µg/l for C. reticulata and 8.0 µg/l for D. magna. In the exposure experiment, we examined the impact of B[a]P on zooplankton community using conceivable concentrations in the environment (5 and 10 µg/l) using typical zooplankton community in eutrophicated systems. Despite the residence time of B[a]P in the water column was short as impacts, suppressing cladoceran populations and inducing the dominance of rotifers particularly under high concentration (10 µg/l). Results have suggested that, even such short duration of B[a]P in the water body can have impact on zooplankton abundance and community structure. Since B[a]P easily precipitate to the bottom and rapidly disappears from the water body, careful monitoring and further assessment of the potential toxicity of polycyclic aromatic hydrocarbons are necessary.

  9. Serum Level of Antibody against Benzo[a]pyrene-7,8-diol-9,10-epoxide-DNA Adducts in People Dermally Exposed to PAHs

    Directory of Open Access Journals (Sweden)

    Lenka Borska

    2014-01-01

    Full Text Available Some specific antibodies indicate the presence of antigenic structures on DNA (DNA adducts that can play an important role in the process of mutagenesis and/or carcinogenesis. They indicate the presence of increased genotoxic potential (hazard prior to the formation of disease (primary prevention. The present study was focused on the serum level of benzo[a]pyrene 7,8-diol-9,10-epoxide-DNA adducts antibodies (anti-BPDE-DNA in psoriatic patients (n=55 dermally exposed to different levels of polycyclic aromatic hydrocarbons (PAHs. The general goal of the study was to contribute to better understanding of the value of the assumed biomarker (anti-BPDE-DNA for evaluation of the organism's answer to genotoxic exposure to PAHs. Elevated level of exposure to PAHs resulted in the increased level of anti-BPDE-DNA. However, almost all levels of anti-BPDE-DNA ranged within the field of low values. Both variants of GT (CCT-3% and CCT-5% induced higher expression of anti-BPDE-DNA in the group of nonsmokers. Significant relations between the level of anti-BPDE-DNA and PASI score, total duration of the therapy, or time of UVR exposure were not found. Further studies are needed to reduce interpretation uncertainty of this promising bioindicator.

  10. Preliminary evidence of the role of hydrogen peroxide in the degradation of benzo[a]pyrene by a non-white rot fungus Fusarium solani

    Energy Technology Data Exchange (ETDEWEB)

    Veignie, Etienne; Rafin, Catherine; Woisel, Patrice; Cazier, Fabrice

    2004-05-01

    In order to study the enzymatic mechanisms involved in the successive steps of BaP degradation by a Deuteromycete fungus Fusarium solani, we developed an indirect approach by using inhibitors of enzymes. We used either specific inhibitors of peroxidases (i.e. salicylhydroxamic acid) and of cytochrome P-450 (i.e. piperonyl butoxyde) or inhibitors of both enzymes (i.e. potassium cyanide). Surprisingly, no expected decrease of BaP degradation was observed with most inhibitors tested. On the contrary, more BaP was degraded. Only butylated hydroxytoluene, which acts as a free radical scavenger, inhibited BaP degradation. The inhibition of these enzymes, which use H{sub 2}O{sub 2} as a cosubstrat, might have resulted in an increase of hydrogen peroxide availability in the fungal cultures. This enhancement could induce formation of reactive oxygen species (ROS) which might be the agents that initiate benzo[a]pyrene oxidation. This study proposed a hypothetic alternative metabolic pathway involved in PAH metabolism by Fusarium solani. - An alternative metabolic pathway was demonstrated.

  11. Intercellular communication amplifies stressful effects in high-charge, high-energy (HZE) particle-irradiated human cells

    International Nuclear Information System (INIS)

    Understanding the mechanisms that underlay the biological effects of particulate radiations is essential for space exploration and for radiotherapy. Here, we investigated the role of gap junction intercellular communication (GJIC) in modulating harmful effects induced in confluent cultures wherein most cells are traversed by one or more radiation tracks. We focused on the effect of radiation quality (linear energy transfer; LET) on junctional propagation of DNA damage and cell death among the irradiated cells. Confluent normal human fibroblasts were exposed to graded doses of 1 GeV protons (LET ∼0.2 keV/μm) or 1 GeV/u iron ions (LET ∼151 keV/μm) and were assayed for clonogenic survival and for micronucleus formation, a reflection of DNA damage, shortly after irradiation and following longer incubation periods. Iron ions were ∼2.7 fold more effective than protons at killing 90% of the cells in the exposed cultures when assayed within 5-10 minutes after irradiation. When cells were held in the confluent state for several hours after irradiation, substantial potentially lethal damage repair (PLDR), coupled with a reduction in micronucleus formation, occurred in cells exposed to protons, but not in those exposed to iron ions. In fact, such confluent holding after exposure to a similarly toxic dose of iron ions enhanced the induced toxic effect. However, following iron ion irradiation, inhibition of GJIC by 18-α-glycyrrhetinic acid eliminated the enhanced toxicity and reduced micronucleus formation to levels below those detected in cells assayed shortly after irradiation. The data show that low-LET radiation induces strong PLDR within hours, but that high-LET radiation with similar immediate toxicity does not induce PLDR and its toxicity increases with time following irradiation. The results also show that GJIC among irradiated cells amplifies stressful effects following exposure to high-, but not low-LET radiation, and that GJIC has only minimal effect on

  12. A split horseradish peroxidase for the detection of intercellular protein-protein interactions and sensitive visualization of synapses.

    Science.gov (United States)

    Martell, Jeffrey D; Yamagata, Masahito; Deerinck, Thomas J; Phan, Sébastien; Kwa, Carolyn G; Ellisman, Mark H; Sanes, Joshua R; Ting, Alice Y

    2016-07-01

    Intercellular protein-protein interactions (PPIs) enable communication between cells in diverse biological processes, including cell proliferation, immune responses, infection, and synaptic transmission, but they are challenging to visualize because existing techniques have insufficient sensitivity and/or specificity. Here we report a split horseradish peroxidase (sHRP) as a sensitive and specific tool for the detection of intercellular PPIs. The two sHRP fragments, engineered through screening of 17 cut sites in HRP followed by directed evolution, reconstitute into an active form when driven together by an intercellular PPI, producing bright fluorescence or contrast for electron microscopy. Fusing the sHRP fragments to the proteins neurexin (NRX) and neuroligin (NLG), which bind each other across the synaptic cleft, enabled sensitive visualization of synapses between specific sets of neurons, including two classes of synapses in the mouse visual system. sHRP should be widely applicable to studying mechanisms of communication between a variety of cell types. PMID:27240195

  13. Effects of anisodamine on the expressions of vascular endothelial growth factor and intercellular adhesion molecule 1 in experimental infusion phlebitis

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhen-xiang; WANG Peng; ZHANG Qiu-shi; PAN Xue; ZHAO Qing-xia; WANG Xiao-kai

    2012-01-01

    Background Infusion phlebitis is the most common side effect of clinical intravenous drug therapy and several clinical studies have demonstrated that anisodamine can effectively prevent the occurrence of infusion phlebitis.This study was designed to investigate effects of anisodamine on the expressions of vascular endothelial growth factor (VEGF) and intercellular adhesion molecule 1 (ICAM-1) in a rabbit model of infusion phlebitis and to analyze the mechanisms of anisodamine effect on the prevention and treatment of experimental infusion phlebitis.Methods Twenty-four specific pathogen-free male Japanese white rabbits were randomly assigned to the control group,the model group,the magnesium sulfate group and the anisodamine group.The rabbit model of infusion phlebitis,induced by intravenous administration,was established and expressions of VEGF and ICAM-1 were determined and contrasted with the control group treated with normal saline.We evaluated expression by histopathology,immunohistochemistry,reverse transcription-polymerase chain reaction,and Western blotting assay.Results Pathohistological changes of the model group were observed,such as loss of venous endothelial cells,inflammatory cell infiltration,edema and thrombus.The magnesium sulfate group and the anisodamine group showed significant protective effects on vascular congestion,inflammatory cell infiltration,proliferation,swelling of endothelium and perivascular hemorrhage.The model group showed the highest expressions of VEGF and ICAM-1 of the four groups (P<0.01).On the contrary,anisodamine alleviated the inflammatory damage by significantly reducing the expressions of VEGF and ICAM-1 compared with the model group (P <0.01).There was no significant difference in the expressions of VEGF and ICAM-1 between the magnesium sulfate group and the anisodamine group (P >0.05).Conclusion Anisodamine alleviates inflammatory damage by significantly reducing the expressions of VEGF and ICAM-1,and shows

  14. Increased Expression of Intercellular Adhesion Molecule-1, Vascular Cellular Adhesion Molecule-1 and Leukocyte Common Antigen in Diabetic Rat Retina

    Institute of Scientific and Technical Information of China (English)

    Ningyan Bai; Shibo Tang; Jing Ma; Yan Luo; Shaofeng Lin

    2003-01-01

    Purpose: To understand the expression and distribution of intercellular adhesion molecule- 1(ICAM- 1),vascular cellular adhesion molecule- 1 (VCAM- 1)and CD45 (Leukocyte Common Antigen) in the control nondiabetic and various courses of diabetic rats retina. To explore the role of adhesion molecules (Ams) and the adhesion of leukocytes to vascular endothelial cells via Ams in diabetic retinopathy(DR).Methods: Sixty healthy adult male Wistar rats were randomly divided into diabetic groups(induced by Streptozotocin, STZ) and normal control groups. Rats in these two groups were further randomly divided into 3, 7, 14, 30, 90 and 180 days-group,including 5 rats respectively. The immunohistochemical studies of ICAM-1, VCAM-1 and CD45 were carried out in the retinal digest preparations or retinal paraffin sections, and the results were analyzed qualitatively, semi-quantitatively.Results: No positive reaction of VCAM-1 was found, and weak reactions of ICAM-1,CD45 were found in nondiabetic rats retina. The difference of 6 control groups had no statistical significance(P > 0.05). The increased ICAM-1 and CD45 staining pattern were detectable 3 days after diabetes induction, and a few VCAM-1 positive cells were observed in the retinal blood capillaries. The difference of diabetes and control is significant( P < 0.05).Following the course, the expressions of ICAM-1, VCAM-1 and CD45 were increasingly enhanced, reaching a peak at the 14th day.Conclusion: Increased expression of ICAM-1, VCAM-1 and leukocytes adhering and stacking in retinal capillaries are the very early events in DR. Coherence of expression and distribution of the three further accounts for it is the key point for the onset of DR that Ams mediates leukocytes adhesion and endothelial cell injury.

  15. Seasonal trends of benzo(apyrene in suspended particulate matter in urban areas of Belgrade, Serbia

    Directory of Open Access Journals (Sweden)

    Snežana Matić-Besarabić

    2010-09-01

    Full Text Available Polycyclic aromatic hydrocarbons (PAHs were identified to be one of the major toxic air pollutants in urban environment. PAHs are mostly formed during incomplete combustion or pyrolysis of organic material. According to Serbian National Legislation, benzo(apyrene (BaP concentration in total suspended particles (TSP in ambient air in the Belgrade metropolitan area has been determined in the last ten years, as a part of a local air pollution monitoring program performed by the Public Health Institute of Belgrade and funded by Belgrade’s Municipality. Air samples for analysis of BaP in suspended particleshave been collected (as 24 h sample once per month at selected onitoring sites within the municipal air quality monitoring network. At the beginning, according to National Regulation, all samples were taken as total suspended particles (TSP. Since mid-2008, the procedure of sampling methodology was harmonized with EU requirements and solid fraction PM10 has been collected and analyzed using GC/MS. In this study, we have analyzed results of TSP collected between 2005 and 2008. Looking through the results obtained during the period of a whole year, it can be noticed that concentrations of BaP were much higher during winter season at almost all measuring sites.

  16. Biodegradation of Benzo[a]pyrene by Arthrobacter oxydans B4

    Institute of Scientific and Technical Information of China (English)

    PENG Hui; YIN Hua; DENG Jun; YE Jin-Shao; CHEN Shuo-Na; HE Bao-Yan; ZHANG Na

    2012-01-01

    A bacterial strain,Arthrobacter oxydans (B4),capable of degrading benzo[a]pyrene (BaP) in water body,was isolated from a polycyclic aromatic hydrocarbons-contaminated site.Effects of different factors,such as reaction time,pH value,temperature and organic nutrients,on BaP biodegradation by the strain B4 were studied.After 5 d treatment,the concentration of BaP in mineral salts medium was reduced to 0.318 mg L-1,compared to the initial concentration of 1.000 mg L-1.There was a process of acid formation during the degradation with pH failing from initial 7.01 to 4.61 at 5 d,so keeping the water body under slightly alkaline condition was propitious to BaP degradation.Strain B4 efficiently degraded BaP at 20 to 37 ℃ with addition of organic nutrients.The biodegradation and transformation of BaP mainly occurred on cell surfaces,and extracellular secretions played an important role in these processes.Fourier transform infrared spectroscopy and gas chromatograph-mass spectrometer analyses of metabolites showed that ring cleavage occurred in the BaP degradation process and the resulting metabolically utilizable substrates were generated as sole carbon sources for B4 growth.Furthermore,mineralization extent of metabolites was verified by determining the total organic carbon and inorganic carbon in the degradation system.

  17. Mouth-Level Intake of Benzo[a]pyrene from Reduced Nicotine Cigarettes

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    Yan S. Ding

    2014-11-01

    Full Text Available Cigarette smoke is a known source of exposure to carcinogenic polycyclic aromatic hydrocarbons (PAHs, especially benzo[a]pyrene (BaP. Exposure to BaP in cigarette smoke is influenced by how a person smokes and factors, such as tobacco blend. To determine whether sustained use of reduced-nicotine cigarettes is associated with changes in exposure to nicotine and BaP, levels of BaP in spent cigarette filter butts were correlated with levels of BaP in cigarette smoke to estimate mouth-level intake (MLI of BaP for 72 daily smokers given three progressively reduced nicotine content cigarettes. Urinary cotinine, a marker of nicotine exposure, and urinary 1-hydroxypyrene (1-HOP, a marker of PAH exposure, were measured throughout the study. Median daily BaP MLI and urine cotinine decreased in a similar manner as smokers switched to progressively lower nicotine cigarettes, despite relatively constant daily cigarette consumption. 1-HOP levels were less responsive to the use of reduced nicotine content cigarettes. We demonstrate that spent cigarette filter butt analysis is a promising tool to estimate MLI of harmful chemicals on a per cigarette or per-day basis, which partially addresses the concerns of the temporal influence of smoking behavior or differences in cigarette design on exposure.

  18. Skin tumor-initiating activities of the twelve isomeric phenols of benzo(a)pyrene

    International Nuclear Information System (INIS)

    The skin tumor-initiating activities of the 12 isomeric phenols of benzo(a)pyrene (BP) were determined in mice by use of a two-stage system of tumorigenesis. 11-Hydroxybenzo(a)pyrene was moderately active, whereas 2-hydroxybenzo(a)pyrene and BP were strong tumor initiators when applied topically to CD-1 mice and followed by twice-weekly applications of the promoter 12-O-tetradecanoylphorbol-13-acetate. 1-, 3-, 4-, 5-, 6-, 7-, 8-, 9-, 10-, and 12-hydroxybenzo(a)pyrene had less than 5% of the tumor-initiating activity of BP when the data were expressed as papillomas per mouse. After 30 weeks of promotion, the number of papillomas per mouse was 8.4, 8.5, and 2.8, respectively, for the animals treated with BP, 2-hydroxybenzo(a)pyrene, and 11-hydroxybenzo(a)pyrene. A 5-week latency period before the appearance of the first tumor was observed after the application of either 2-hydroxybenzo(a)pyrene or BP, whereas a slightly longer latency period of 7 weeks was observed following application of 11-hydroxybenzo(a)pyrene. The time required for 50% of the animals to develop tumors was 13 weeks for animals treated with BP and 15 weeks for animals treated with 2- or 11-hydroxybenzo(a)pyrene

  19. Benzo[a]pyrene and Benzo[k]fluoranthene in some processed fish and fish products.

    Science.gov (United States)

    Olatunji, Olatunde S; Fatoki, Olalekan S; Opeolu, Beatrice O; Ximba, Bhekumusa J

    2015-01-01

    In this study, the concentration levels of the probable carcinogenic PAH fractions, benzo[a]pyrene (BaP) and benzo[k]fluoranthrene (BkF) in fillets of some processed fish species were investigated. Fish species comprising Merluccius poli (hake), Tyrsites atun (snoek), Seriola lalandi (yellow-tail) and Brama brama (angel fish) were bought in fish shops at Gordon's Bay, Western Cape, South Africa. The fish were gutted, filleted and prepared for edibility by frying, grilling and boiling. Polycyclic aromatic hydrocarbons were extracted from each homogenized fish sample, cleaned-up using solid phase extraction (SPE), and analysed for the PAH fractions, BaP and BkF using a Gas Chromatograph coupled with a Flame Ionization Detector (GC-FID). The sum of the two PAHs (∑2PAH) i.e., BaP and BkF ranged between 0.56 and 1.46 µg/kg, in all boiled, grilled and fried fish species. The fried fish extracts showed significantly higher (p < 0.05) abundance of ∑2PAH, than grilled and boiled fish. Dietary safety and PAHs toxicity was also discussed. PMID:25607603

  20. Benzo[a]pyrene and Benzo[k]fluoranthene in Some Processed Fish and Fish Products

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    Olatunde S. Olatunji

    2015-01-01

    Full Text Available In this study, the concentration levels of the probable carcinogenic PAH fractions, benzo[a]pyrene (BaP and benzo[k]fluoranthrene (BkF in fillets of some processed fish species were investigated. Fish species comprising Merluccius poli (hake, Tyrsites atun (snoek, Seriola lalandi (yellow-tail and Brama brama (angel fish were bought in fish shops at Gordon’s Bay, Western Cape, South Africa. The fish were gutted, filleted and prepared for edibility by frying, grilling and boiling. Polycyclic aromatic hydrocarbons were extracted from each homogenized fish sample, cleaned-up using solid phase extraction (SPE, and analysed for the PAH fractions, BaP and BkF using a Gas Chromatograph coupled with a Flame Ionization Detector (GC-FID. The sum of the two PAHs (∑2PAH i.e., BaP and BkF ranged between 0.56 and 1.46 µg/kg, in all boiled, grilled and fried fish species. The fried fish extracts showed significantly higher (p < 0.05 abundance of ∑2PAH, than grilled and boiled fish. Dietary safety and PAHs toxicity was also discussed.

  1. Transcriptional signatures of regulatory and toxic responses to benzo-[a]-pyrene exposure

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    Schirmer Kristin

    2011-10-01

    Full Text Available Abstract Background Small molecule ligands often have multiple effects on the transcriptional program of a cell: they trigger a receptor specific response and additional, indirect responses ("side effects". Distinguishing those responses is important for understanding side effects of drugs and for elucidating molecular mechanisms of toxic chemicals. Results We explored this problem by exposing cells to the environmental contaminant benzo-[a]-pyrene (B[a]P. B[a]P exposure activates the aryl hydrocarbon receptor (Ahr and causes toxic stress resulting in transcriptional changes that are not regulated through Ahr. We sought to distinguish these two types of responses based on a time course of expression changes measured after B[a]P exposure. Using Random Forest machine learning we classified 81 primary Ahr responders and 1,308 genes regulated as side effects. Subsequent weighted clustering gave further insight into the connection between expression pattern, mode of regulation, and biological function. Finally, the accuracy of the predictions was supported through extensive experimental validation. Conclusion Using a combination of machine learning followed by extensive experimental validation, we have further expanded the known catalog of genes regulated by the environmentally sensitive transcription factor Ahr. More broadly, this study presents a strategy for distinguishing receptor-dependent responses and side effects based on expression time courses.

  2. Effects of 2,3,7,8-TCDD and benzo[a]pyrene on modulating vitellogenin expression in primary culture of crucian carp (Carassius auratus) hepatocytes

    Institute of Scientific and Technical Information of China (English)

    LIANG Yong; C. K. C. Wong; XU Ying; M. H. Wong

    2004-01-01

    Vitellogenin (Vtg) is the precursor of yolk protein. Its expression and secretion are estrogen-regulated and are crucial for oocyte maturation. An in vitro xenoestrogen screening model was established by measuring Vtg induction in cultured primary hepatocytes from crucian carp. Vtg production was detected by biotin-avidin sandwich ELISA method while Vtg and cytochrome P4501A1 (CYP1A1) mRNA induction were measured by semi- quantitative PCR-primer dropping technique. Vtg and Vtg mRNA were dose-dependently induced by diethylstilbestrol (DES, 0.2-200 ng/mL) in hepatocytes of crucian carp. Co-treatment of the DES-induced hepatocytes with either 2,3,7,8-TCDD (TCDD, 0.1-4 pg/mL) or benzo[a]pyrene (B[a]P, 5-1000 ng/mL) resulted in a reduction of Vtg production and an increment of CYP1A1 mRNA expression both in a dose dependent manner, indicating the anti-estro-genic effects of the compounds. However, at lower tested concentrations, TCDD (0.1, 0.2 pg/mL), B[a]P (5 ng/mL) seemed to have a potentiating effect on Vtg expression and secretion, although by their own these compounds had no observable estrogenic effect on Vtg induction. Tamoxifen (a selective estrogen receptor modulators, 1 nmol/L-1 μmol/L), and β-naphtho-flavone (β-NF, an aryl hydrocarbon receptor inducing compounds, 2.5-1000 ng/mL) also were employed to study the possible interactions in DES-induced Vtg expression. In co-treatment of the DES-induced hepatocytes with β-NF or tamoxifen, the decrease in Vtg production did parallel induction of CYP1A1 for β-NF, but tamoxifen inhibited Vtg induction did not parallel induced CYP1A1 expression in all test concentrations. On the contrary, it was found that in co-treatment of the TCDD-induced hepatocytes with DES, TCDD induced CYP1A1 mRNA production was inhibited by DES also. These results implicated a possible cross talk between estrogen receptor- and aryl hydrocarbon receptor-mediated pathways in the hepatocytes.

  3. Cadherin-Based Intercellular Adhesions Organize Epithelial Cell-Matrix Traction Forces

    CERN Document Server

    Mertz, Aaron F; Banerjee, Shiladitya; Goldstein, Jill; Rosowski, Kathryn R; Niessen, Carien M; Marchetti, M Cristina; Dufresne, Eric R; Horsley, Valerie

    2012-01-01

    Cell--cell and cell-matrix adhesions play essential roles in the function of tissues. There is growing evidence for the importance of crosstalk between these two adhesion types, yet little is known about the impact of these interactions on the mechanical coupling of cells to the extracellular-matrix (ECM). Here, we combine experiment and theory to reveal how intercellular adhesions modulate forces transmitted to the ECM. In the absence of cadherin-based adhesions, primary mouse keratinocytes within a colony appear to act independently, with significant traction forces extending throughout the colony. In contrast, with strong cadherin-based adhesions, keratinocytes in a cohesive colony localize traction forces to the colony periphery. Through genetic or antibody-mediated loss of cadherin expression or function, we show that cadherin-based adhesions are essential for this mechanical cooperativity. A minimal physical model in which cell--cell adhesions modulate the physical cohesion between contractile cells is ...

  4. Inhibitors of 5-lipoxygenase inhibit expression of intercellular adhesion molecule-1 in human melanoma cells

    Institute of Scientific and Technical Information of China (English)

    Yin WANG; Bin ZHOU; Ji LI; Yong-bing CAO; Xin-sheng CHEN; Ming-he CHENG; Ming YIN

    2004-01-01

    AIM: To study the effect of 5-lipoxygenase inhibitors on the expression of intercellular adhesion molecule-1 (ICAM-1) in melanoma cells. METHODS: ICAM-1 protein of human melanoma cell a375 was detected by enzyme-linked immunosorbent, flow cytometry and Western blot analysis. Level of ICAM-1 mRNA in a375 was evaluated by Northern blot analysis. Adhesion of a375 to endothelial cell EC304 was analyzed by isotopic tracing. RESULTS:5-Lipoxygenase inhibitors nordihydroguaiaretic acid, AA861 and MK886, could suppress the expression of ICAM-1 protein as well as of its mRNA in a375 cells and reduce the adhesion of a375 to EC304. CONCLUSION:5-Lipoxygenase inhibitors can inhibit the expression of ICAM-1 in human melanoma cells and may be valuable for treatment of melanoma metastasis.

  5. [Cryofractographic study of intercellular junctions in the populations of agar-cultivated Bordetella pertussis].

    Science.gov (United States)

    Vysotskiĭ, V V; Vaisman, I Sh; Efimova, O G; Chemurzieva, N V

    1985-09-01

    The characteristic feature of replicas obtained from the freeze-fractures of B. pertussis unfixed cultures developing on casein charcoal agar for 1-7 days is the associative growth of highly polymorphic cells, ensured by the ramified system of intercellular connections (IC) formed by the derivatives of the outer layers of the cell wall. This proves that the associative location of bacterial cells, linked by numerous IC, in the preparation is not the artefact appearing in the process of their chemical fixation. In replicas obtained from the freeze-fractures of B. pertussis cultures, previously fixed with glutaraldehyde, osmic acid and uranyl acetate, oval cells with the cytoplasm having a relatively homogeneous structure and with the smoothed-out three-layer cell wall prevail. As a rule, IC are limited to the sites of direct contacts between individual cells. PMID:2866645

  6. Metazoans evolved by taking domains from soluble proteins to expand intercellular communication network.

    Science.gov (United States)

    Nam, Hyun-Jun; Kim, Inhae; Bowie, James U; Kim, Sanguk

    2015-01-01

    A central question in animal evolution is how multicellular animals evolved from unicellular ancestors. We hypothesize that membrane proteins must be key players in the development of multicellularity because they are well positioned to form the cell-cell contacts and to provide the intercellular communication required for the creation of complex organisms. Here we find that a major mechanism for the necessary increase in membrane protein complexity in the transition from non-metazoan to metazoan life was the new incorporation of domains from soluble proteins. The membrane proteins that have incorporated soluble domains in metazoans are enriched in many of the functions unique to multicellular organisms such as cell-cell adhesion, signaling, immune defense and developmental processes. They also show enhanced protein-protein interaction (PPI) network complexity and centrality, suggesting an important role in the cellular diversification found in complex organisms. Our results expose an evolutionary mechanism that contributed to the development of higher life forms. PMID:25923201

  7. Serum Soluble Intercellular Adhesion Molecule-1 Level in Acute Lymphoblastic Leukemia in Children

    International Nuclear Information System (INIS)

    Impaired migration of leucocytes is a characteristic feature of leukemia. Knowledge of the mechanisms of leukemic cells migration has expanded greatly in recent years. Leukocyte infiltrates are formed in surrounding tissues due to changes in chemokines and adhesion molecules concentrations. The present study included 45 patients with acute lymphoblastic leukemia (ALL). The mean of their ages was 6.10±4.39 years. They were 29 males and 16 females. They were chosen from those attending the Oncology Clinic and inpatient wards of the National Cancer Institute, Cairo University. They were classified into 3 groups according to the disease activity: Group I: Comprised 15 newly diagnosed cases of ALL. Group II: Consisted of 15 cases of ALL during relapse period. Group III included 15 cases of ALL during complete remission. Also, 15 apparently healthy children with matched age and sex as a control group (group IV). All the studied cases were subjected to thorough clinical examination as well as the following investigations: complete blood picture, bone marrow biopsy and estimation of serum intercellular adhesion molecule-1 (sICAM-1) by ELISA.The results of this study revealed that serum ICAM-l showed no significant changes in its value on comparing group I (newly diagnosed cases) and group II (cases during relapse). On the other hand, a significant higher level of sICAM-1 was observed on comparing groups I and II with group III (cases during remission) separately (P0.05).From this it was concluded that the levels of serum soluble intercellular circulating adhesion molecule ICAM-1 can be utilized for monitoring disease activity of ALL and its response to treatment, as well as for early detection of relapse.

  8. The role of cholesterol-sphingomyelin membrane nanodomains in the stability of intercellular membrane nanotubes

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    Veranič P

    2012-04-01

    Full Text Available Maruša Lokar1,*, Doron Kabaso1,2,*, Nataša Resnik3, Kristina Sepcic5, Veronika Kralj-Iglic4,6, Peter Veranic3, Robert Zorec2, Aleš Iglic1,6 1Laboratory of Biophysics, Faculty of Electrical Engineering, 2Laboratory of Neuroendocrinology-Molecular Cell Physiology, Faculty of Medicine, 3Institute of Cell Biology, Faculty of Medicine, 4Faculty of Health Sciences, 5Department of Biology, Biotechnical Faculty, 6Laboratory of Clinical Biophysics, Department of Orthopedic Surgery, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia*These authors equally share first authorshipAbstract: Intercellular membrane nanotubes (ICNs are highly curved tubular structures that connect neighboring cells. The stability of these structures depends on the inner cytoskeleton and the cell membrane composition. Yet, due to the difficulty in the extraction of ICNs, the cell membrane composition remains elusive. In the present study, a raft marker, ostreolysin, revealed the enrichment of cholesterol-sphingomyelin membrane nanodomains along ICNs in a T24 (malignant urothelial cancer cell line. Cholesterol depletion, due to the addition of methyl-β-cyclodextrin, caused the dispersion of cholesterol-sphingomyelin membrane nanodomains and the retraction of ICNs. The depletion of cholesterol also led to cytoskeleton reorganization and to formation of actin stress fibers. Live cell imaging data revealed the possible functional coupling between the change from polygonal to spherical shape, cell separation, and the disconnection of ICNs. The ICN was modeled as an axisymmetric tubular structure, enabling us to investigate the effects of cholesterol content on the ICN curvature. The removal of cholesterol was predicted to reduce the positive spontaneous curvature of the remaining membrane components, increasing their curvature mismatch with the tube curvature. The mechanisms by which the increased curvature mismatch could contribute to the disconnection of ICNs are

  9. Detection of the intercellular adhesion gene cluster (ica in clinical Staphylococcus aureus isolates

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    Namvar, Amirmorteza Ebrahimzadeh

    2013-04-01

    Full Text Available [english] is a major hospital and community pathogen having the aptitude to cause a wide variety of infections in men. The ability of microorganisms to produce biofilm facilitates them to withstand the host immune response and is recognized as one factor contributing to chronic or persistent infections. It was demonstrated that the -encoded genes lead to the biosynthesis of polysaccharide intercellular adhesion (PIA molecules, and may be involved in the accumulation phase of biofilm formation. Different studies have shown the decisive role of the gene as virulence factors in staphylococcal infections. This study was carried out to demonstrate the relationship between gene and production of slime layer in strains. Sixty strains were isolated from patients. The isolates were identified morphologically and biochemically following standard laboratory methods. After identification, the staphylococcal isolates were maintained in trypticase soy broth (TSB, to which 15% glycerol was added, and stored at –20°C. Slime formation and biofilm assay was monitored. A PCR assay was developed to identify the presence of (intercellular adhesion gene gene in all isolates. Thirty-nine slime producing colonies with CRA plates (65% formed black colors, the remaining 21 isolates were pink (35%. In the quantitative biofilm assay 35 (58% produced biofilm while 25 (42% isolates did not exhibit this property. All isolates were positive for detection of gene by PCR method. The interaction of and in the investigated isolates may be important in slime layer formation and biofilm phenomena.We propose PCR detection of the gene locus as a rapid and effective method to be used for discrimination between potentially virulent and nonvirulent isolates, with implications for therapeutic and preventive measures pertainin to the management of colonized indwelling catheters.

  10. Microfluidic systems to examine intercellular coupling of pairs of cardiac myocytes.

    Science.gov (United States)

    Klauke, Norbert; Smith, Godfrey; Cooper, Jonathan M

    2007-06-01

    In this paper we describe a microfluidic environment that enables us to explore cell-to-cell signalling between longitudinally linked primary heart cells. We have chosen to use pairs (or doublets) of cardiac myocyte as a model system, not only because of the importance of cell-cell signalling in the study of heart disease but also because the single cardiomyocytes are both mechanically and electrically active and their synchronous activation due to the intercellular coupling within the doublet can be readily monitored on optical and electrical recordings. Such doublets have specialised intercellular contact structures in the form of the intercalated discs, comprising the adhesive junction (fascia adherens and macula adherens or desmosome) and the connecting junction (known as gap junction). The latter structure enables adjacent heart cells to share ions, second messengers and small metabolites (<1 kDa) between them and thus provides the structural basis for the synchronous (syncytical) behaviour of connected cardiomyocytes. Using the unique environment provided by the microfluidic system, described in this paper, we explore the local ionic conditions that enable the propagation of Ca(2+) waves between two heart cells. We observe that the ability of intracellular Ca(2+) waves to traverse the intercalated discs is dependent on the relative concentrations of diastolic Ca(2+) in the two adjacent cells. These experiments rely upon our ability to independently control both the electrical stimulation of each of the cells (using integrated microelectrodes) and to rapidly change (or switch) the local concentrations of ions and drugs in the extracellular buffer within the microfluidic channel (using a nanopipetting system). Using this platform, it is also possible to make simultaneous optical recordings (including fluorescence and cell contraction) to explore the effect of drugs on one or both cells, within the doublet.

  11. Modulation of intercellular communication by differential regulation and heteromeric mixing of co-expressed connexins

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    Beyer E.C.

    2000-01-01

    Full Text Available Intercellular communication may be regulated by the differential expression of subunit gap junction proteins (connexins which form channels with differing gating and permeability properties. Endothelial cells express three different connexins (connexin37, connexin40, and connexin43 in vivo. To study the differential regulation of expression and synthesis of connexin37 and connexin43, we used cultured bovine aortic endothelial cells which contain these two connexins in vitro. RNA blots demonstrated discordant expression of these two connexins during growth to confluency. RNA blots and immunoblots showed that levels of these connexins were modulated by treatment of cultures with transforming growth factor-ß1. To examine the potential ability of these connexins to form heteromeric channels (containing different connexins within the same hemi-channel, we stably transfected connexin43-containing normal rat kidney (NRK cells with connexin37 or connexin40. In the transfected cells, both connexin proteins were abundantly produced and localized in identical distributions as detected by immunofluorescence. Double whole-cell patch-clamp studies showed that co-expressing cells exhibited unitary channel conductances and gating characteristics that could not be explained by hemi-channels formed of either connexin alone. These observations suggest that these connexins can readily mix with connexin43 to form heteromeric channels and that the intercellular communication between cells is determined not only by the properties of individual connexins, but also by the interactions of those connexins to form heteromeric channels with novel properties. Furthermore, modulation of levels of the co-expressed connexins during cell proliferation or by cytokines may alter the relative abundance of different heteromeric combinations.

  12. Implications of Intercellular Signaling for Radiation Therapy: A Theoretical Dose-Planning Study

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-12-01

    Purpose: Recent in vitro results have shown significant contributions to cell killing from signaling effects at doses that are typically used in radiation therapy. This study investigates whether these in vitro observations can be reconciled with in vivo knowledge and how signaling may have an impact on future developments in radiation therapy. Methods and Materials: Prostate cancer treatment plans were generated for a series of 10 patients using 3-dimensional conformal therapy, intensity modulated radiation therapy (IMRT), and volumetric modulated arc therapy techniques. These plans were evaluated using mathematical models of survival following modulated radiation exposures that were developed from in vitro observations and incorporate the effects of intercellular signaling. The impact on dose–volume histograms and mean doses were evaluated by converting these survival levels into “signaling-adjusted doses” for comparison. Results: Inclusion of intercellular communication leads to significant differences between the signalling-adjusted and physical doses across a large volume. Organs in low-dose regions near target volumes see the largest increases, with mean signaling-adjusted bladder doses increasing from 23 to 33 Gy in IMRT plans. By contrast, in high-dose regions, there is a small decrease in signaling-adjusted dose due to reduced contributions from neighboring cells, with planning target volume mean doses falling from 74 to 71 Gy in IMRT. Overall, however, the dose distributions remain broadly similar, and comparisons between the treatment modalities are largely unchanged whether physical or signaling-adjusted dose is compared. Conclusions: Although incorporating cellular signaling significantly affects cell killing in low-dose regions and suggests a different interpretation for many phenomena, their effect in high-dose regions for typical planning techniques is comparatively small. This indicates that the significant signaling effects observed in vitro

  13. Xeroderma pigmentosum, complementation group D expression in H1299 lung cancer cells following benzo[a]pyrene exposure as well as in head and neck cancer patients.

    Science.gov (United States)

    Lin, Chang-Shen; Chiou, Wen-Yen; Lee, Ka-Wo; Chen, Tzu-Fen; Lin, Yuan-Jen; Huang, Jau-Ling

    2016-01-01

    DNA repair genes play critical roles in response to carcinogen-induced and anticancer therapy-induced DNA damage. Benzo[a]pyrene (BaP), the most carcinogenic polycyclic aromatic hydrocarbon (PAH), is classified as a group 1 carcinogen by International Agency for Research on Cancer. The aims of this study were to (1) evaluate the effects of BaP on DNA repair activity and expression of DNA repair genes in vitro and (2) examine the role of xeroderma pigmentosum, complementation group D (XPD) mRNA expression in human head and neck cancers. Host cell reactivation assay showed that BaP inhibited nucleotide excision repair in H1299 lung cancer cells. DNA repair through the non-homologous end-joining pathway was not affected by BaP. Real-time quantitative reverse-transcription polymerase chain reaction (RT-PCR) and Western blot demonstrated that XPD was downregulated by BaP treatment. BaP exposure did not apparently affect expression of another 11 DNA repair genes. BaP treatment increased the DNA damage marker γ-H2AX and ultraviolet (UV) sensitivity, supporting an impairment of DNA repair in BaP-treated cells. XPD expression was also examined by quantitative RT-PCR in 68 head and neck cancers, and a lower XPD mRNA level was found in smokers' cancer specimens. Importantly, reduced XPD expression was correlated with patient 5-year overall survival rate (35 vs. 56%) and was an independent prognostic factor (hazard ratio: 2.27). Data demonstrated that XPD downregulation was correlated with BaP exposure and human head and neck cancer survival. PMID:26731659

  14. The Japanese medaka (Oryzias latipes) model: applicability for investigating the immunosuppressive effects of the aquatic pollutant benzo[a]pyrene (BaP).

    Science.gov (United States)

    Carlson, E A; Li, Y; Zelikoff, J T

    2002-01-01

    Despite the fact that BaP is a carcinogen, mammalian immunosuppressant, and ubiquitous aquatic pollutant, knowledge regarding the effects of BaP on the immune system of fish is still lacking. To begin to fill this gap, studies were conducted in medaka to examine the effects and mechanisms by which BaP exposure might alter host immunocompetence. Fish, exposed by IP injection of BaP (2-600 microg/g BW), were examined after 48 h for effects upon immune function and CYP1A expression/activity. Benzo[a]pyrene, at a concentration below that which increased levels of CYPIA expression/activity (2 microg BaP/g BW) suppressed lymphocyte proliferation. Concentrations of BaP at 20 and 200 microg/g BW. suppressed antibody-forming cell (AFC) numbers, superoxide production, and host resistance against bacteria. In contrast, exposure to the low affinity aryl hydrocarbon receptor (AhR) agonist, benzo[e]pyrene (BeP), neither induced CYP1A expression nor altered immune function. Given the lack of immunosuppressive effects produced by BeP, and the fact that exposure to the AhR antagonist (and CYP1A inhibitor) alpha-naphthoflavone (ANF) ameliorated the suppressive effects of BaP upon AFC numbers, the AhR pathway (including CYP1A-mediated production of reactive BaP metabolites) appears important in mediating BaP-induced immunotoxicity in fish, as in mammals. In the past, the medaka has proven a successful model for assessing carcinogenic agents. These studies have demonstrated its utility for also determining the immunosuppressive effects of an important aquatic contaminant.

  15. Influence of dietary Coexposure to benzo(a)pyrene on the biotransformation and distribution of 14C-methoxychlor in the channel catfish (Ictalurus punctatus).

    Science.gov (United States)

    Nyagode, Beatrice A; James, Margaret O; Kleinow, Kevin M

    2009-04-01

    Methoxychlor (MXC) is an organochlorine pesticide whose mono- and bis-demethylated metabolites, 2-(4-hydroxyphenyl)-2-(4-methoxyphenyl)-1,1,1-trichloroethane (OH-MXC) and 2,2-bis(4-hydroxyphenyl)-1,1,1-trichloroethane (HPTE), respectively, are estrogenic and antiandrogenic. Studies in vitro showed that treatment of channel catfish with a polycyclic aromatic hydrocarbon increased phase I and phase II metabolism of MXC. To determine the in vivo significance, groups of four channel catfish were treated by gavage for 6 days with 2 mg/kg (14)C-MXC alone or 2 mg/kg (14)C-MXC and 2 mg/kg benzo(a)pyrene (BaP). On day 7, blood and tissue samples were taken for analysis. Hepatic ethoxyresorufin O-deethylase activity was 10-fold higher in the BaP-treated catfish, indicating CYP1A induction. More MXC-derived radioactivity remained in control (42.8 +/- 4.1%) than BaP-induced catfish (28.5 +/- 3.2%), mean percent total dose +/- SE. Bile, muscle and fat contained approximately 90% of the radioactivity remaining in control and induced catfish. Extraction and chromatographic analysis showed that liver contained MXC, OH-MXC, HPTE, and glucuronide but not sulfate conjugates of OH-MXC and HPTE. Liver mitochondria contained more MXC, OH-MXC, and HPTE than other subcellular fractions. Bile contained glucuronides of OH-MXC and HPTE, and hydrolysis of bile gave HPTE and both enantiomers of OH-MXC. The muscle, visceral fat, brain and gonads contained MXC, OH-MXC, and HPTE in varying proportions, but no conjugates. This study showed that catfish coexposed to BaP and MXC retained less MXC and metabolites in tissues than those exposed to MXC alone, suggesting that induction enhanced the elimination of MXC, and further showed that potentially toxic metabolites of MXC were present in the edible tissues.

  16. The extreme variety of genotoxic response to benzo[a]pyrene in three different human cell lines from three different organs.

    Directory of Open Access Journals (Sweden)

    Camille Genies

    Full Text Available Polycyclic aromatic hydrocarbons (PAHs are associated with occupational exposure and urban atmospheric pollution. Determination of the genotoxic properties of these compounds is thus of outmost importance. For this purpose a variety of cellular models have been widely used. Reliable results can however only be obtained with models reflecting the specific sensitivity of different organs towards PAHs. In this work, we compared the response to benzo[a]pyrene in cell lines from human lungs (A549 and bladder (T24; two important target organs for PAHs-induced cancer. Human hepatocytes (HepG2 were used as a reference, although liver is not a concern for PAHs carcinogenesis. Adducts arising from the ultimate diol-epoxide metabolite of B[a]P, BPDE, were found to be produced in a dose-dependent manner in HepG2. BPDE DNA adducts were not detected in T24 and in A549 their formation was found to be most efficient at the lowest concentration studied (0.2 µM. These results are probably explained by differences in induction and activity of phase I metabolization enzymes, as well as by proteins eliminating the B[a]P epoxide in A549. In addition to BPDE adducts, oxidative DNA damage, namely strand breaks and oxidized purines were measured and found to be produced only in minute amounts in all three cell lines. In summary, our results emphasize the large differences in the response of cells originating from different organs. Our data also point out the importance of carefully selecting the doses used in in vitro toxicological experiments. The example of A549 shows that working at high doses may lead to an underestimation of the risk. Finally, the choice of method for evaluating genotoxicity appears to be of crucial importance. The comet assay does not seem to be the best method for a compound like B[a]P which induces stable adducts causing limited oxidative damage.

  17. Effects of benzo[a]pyrene on mitochondrial and nuclear DNA damage in Atlantic killifish (Fundulus heteroclitus) from a creosote-contaminated and reference site

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Dawoon; Cho, Youngeun [Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States); Collins, Leonard B.; Swenberg, James A. [Center for Environmental Health and Susceptibility, Gillings School of Global Public Health, University of North Carolina-Chapel Hill, Chapel Hill, NC 27599 (United States); Di Giulio, Richard T., E-mail: richd@duke.edu [Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States)

    2009-10-19

    Benzo[a]pyrene (BaP) is a known genotoxicant that affects both mitochondrial and nuclear DNA (mtDNA, nDNA). Here, we examined mtDNA and nDNA damage in the Atlantic killifish (Fundulus heteroclitus) from a highly contaminated Superfund site (Elizabeth River, VA, USA) and from a reference site (King's Creek, VA, USA) that were dosed with 10 mg/kg BaP. Using the long amplicon quantitative PCR technique, we observed similar increases in mitochondrial and nuclear DNA damage in King's Creek fish treated with BaP. Killifish from the Elizabeth River showed high levels of basal nDNA and mtDNA damage compared to fish from the reference site, but the level of damage induced due to BaP treatment was much lower in Elizabeth River killifish compared to King's Creek fish. Laboratory-reared offspring from both populations showed increased BaP-induced damage in mtDNA, relative to nDNA. Similar to the adult experiment, the Elizabeth River larvae had higher levels of basal DNA damage than those from the reference site, but were less impacted by BaP exposure. Measurements of oxidative DNA damage (8-oxo-deoxyguanine by LC-MS/MS) showed no differences among treatment groups, suggesting that the majority of DNA damage is from covalent binding of BaP metabolites to DNA. This study shows for the first time that mitochondria can be an important target of BaP toxicity in fish, indicating that BaP exposures could have important energetic consequences. Results also suggest that multi-generational exposures in the wild may lead to adaptations that dampen DNA damage arising from BaP exposure.

  18. Cooperative interaction of benzo[a]pyrene and ethanol on plasma membrane remodeling is responsible for enhanced oxidative stress and cell death in primary rat hepatocytes.

    Science.gov (United States)

    Collin, Aurore; Hardonnière, Kevin; Chevanne, Martine; Vuillemin, Julie; Podechard, Normand; Burel, Agnès; Dimanche-Boitrel, Marie-Thérèse; Lagadic-Gossmann, Dominique; Sergent, Odile

    2014-07-01

    Several epidemiologic studies have shown an interactive effect of heavy smoking and heavy alcohol drinking on the development of hepatocellular carcinoma. It has also been recently described that chronic hepatocyte death can trigger excessive compensatory proliferation resulting later in the formation of tumors in mouse liver. As we previously demonstrated that both benzo[a]pyrene (B[a]P), an environmental agent found in cigarette smoke, and ethanol possess similar targets, especially oxidative stress, to trigger death of liver cells, we decided to study here the cellular and molecular mechanisms of the effects of B[a]P/ethanol coexposure on cell death. After an 18-h incubation with 100nM B[a]P, primary rat hepatocytes were supplemented with 50mM ethanol for 5 or 8h. B[a]P/ethanol coexposure led to a greater apoptotic cell death that could be linked to an increase in lipid peroxidation. Plasma membrane remodeling, as depicted by membrane fluidity elevation and physicochemical alterations in lipid rafts, appeared to play a key role, because both toxicants acted with specific complementary effects. Membrane remodeling was shown to induce an accumulation of lysosomes leading to an important increase in low-molecular-weight iron cellular content. Finally, ethanol metabolism, but not that of B[a]P, by providing reactive oxygen species, induced the ultimate toxic process. Indeed, in lysosomes, ethanol promoted the Fenton reaction, lipid peroxidation, and membrane permeabilization, thereby triggering cell death. To conclude, B[a]P exposure, by depleting hepatocyte membrane cholesterol content, would constitute a favorable ground for a later toxic insult such as ethanol intoxication. Membrane stabilization of both plasma membrane and lysosomes might be a potential target for further investigation considering cytoprotective strategies. PMID:24681337

  19. The predominant mechanism of intercellular calcium wave propagation changes during long-term culture of human osteoblast-like cells

    DEFF Research Database (Denmark)

    Henriksen, Zanne; Hiken, Jeffrey F; Steinberg, Thomas H;

    2006-01-01

    , but as cells differentiate in culture, gap-junction-mediated ICW become more prominent. These results suggest that P2Y receptor-mediated and gap junction-mediated mechanisms of intercellular calcium signaling may play different roles during differentiation of bone-forming cells....

  20. Activation of L-type calcium channels is required for gap junction-mediated intercellular calcium signaling in osteoblastic cells

    DEFF Research Database (Denmark)

    Jørgensen, Niklas Rye; Teilmann, Stefan Cuoni; Henriksen, Zanne;

    2003-01-01

    in "slow" ICW. Human osteoblastic cells transmit intercellular calcium signals by both of these mechanisms. In the current studies we have examined the mechanism of slow gap junction-dependent ICW in osteoblastic cells. In ROS rat osteoblastic cells, gap junction-dependent ICW were inhibited by removal...

  1. Intercellular deposits of basement membrane material in active human pituitary adenomas detected by immunostaining for laminin and electron microscopy

    DEFF Research Database (Denmark)

    Holck, S; Wewer, U M; Albrechtsen, R

    1986-01-01

    and one patient with Cushing's syndrome). Concurrently, at the ultrastructural level, bunches of basement membrane-like material intermingled between the adenoma cells were demonstrated in seven of these ten active adenomas. Furthermore, secretory granules were entrapped occasionally in this intercellular...

  2. Intercellular communication and cell proliferation in precision-cut rat liver slices : effect of medium composition and DDT

    NARCIS (Netherlands)

    Graaf, I.A.M.; Tajima, O.; Groten, J.P.; Wolterbeek, A.P.M.

    2000-01-01

    Gap junctional intercellular communication (GJIC) and cell proliferation were studied in control and 1,1'-bis(p-chlorophenyl)-2,2,2,-trichloroethane (DDT) treated precision-cut liver slices of rat by evaluating connexin 32 (Cx32) expression and 5-bromo-2'-deoxyuridine (BrdU) incorporation. In additi

  3. Functional mapping of the cytoplasmic region of intercellular adhesion molecule-3 reveals important roles for serine residues

    NARCIS (Netherlands)

    Hayflick, J S; Stine, J; Fox, R; Hoekstra, D; Gallatin, W M

    1997-01-01

    Intercellular adhesion molecule-3 (ICAM-3), a ligand for beta2 integrins, elicits a variety of activation responses in lymphocytes. We describe a functional mapping study that focuses on the 37-residue cytoplasmic region of ICAM-3. Carboxyl-terminal truncations delineated portions involved in T cell

  4. Intercellular communication and cell proliferation in precision-cut rat liver slices : effect of medium composition and DDT

    NARCIS (Netherlands)

    de Graaf, I A; Tajima, O; Groten, J P; Wolterbeek, A P

    2000-01-01

    Gap junctional intercellular communication (GJIC) and cell proliferation were studied in control and 1,1'-bis(p-chlorophenyl)-2, 2,2,-trichloroethane (DDT) treated precision-cut liver slices of rat by evaluating connexin 32 (Cx32) expression and 5-bromo-2'-deoxyuridine (BrdU) incorporation. In addit

  5. Effect of the Apulia air quality plan on PM10 and benzo(apyrene exceedances

    Directory of Open Access Journals (Sweden)

    L. Trizio

    2016-03-01

    Full Text Available During the last years, several exceedances of PM10 and benzo(apyrene limit values exceedances were recorded in Taranto, a city in southern Italy included in so-called areas at high risk of environmental crisis because of the presence of a heavy industrial district including the largest steel factory in Europe. A study of these critical pollution events showed a close correlation with the wind coming from the industrial site to the adjacent urban area. During 2011, at monitoring sites closes to the industrial area, at least the 65% of PM10 exceedances were related to wind day conditions (characterized by at least 3 consecutive hours of wind coming from 270-360±2deg with an associated speed higher than 7 m/s. For this reason, in 2012 an integrated environmental permit and a regional air quality plan were enacted to reduce pollutant emissions from industrial plants. A study of PM10 levels registered during windy days was performed during critical episodes of pollution highlighting that the difference between windy days and no windy days’ concentrations reduces from 2012 to 2014 in industrial site. False negative events (verified ex-post by observed meteorological data not identified by the forecast model - did not show a significant influence on PM concentration: PM10 values were comparable and sometimes lower than windy days levels. It is reasonable that the new scenario with a relevant reduction emissions form Ilva plant reduced the pollutants contribution from industrial area, contributing to PM10 levels decrease, also in false negative events.

  6. Alterations of rat liver mitochondrial oxidative phosphorylation and calcium uptake by benzo[a]pyrene

    International Nuclear Information System (INIS)

    We report that oxidative phosphorylation and Ca2+ uptake processes are enhanced in liver mitochondria isolated from benzo[a]pyrene (B[a]P)-treated rats. The carcinogen did not affect either the respiratory control index or the Ca2+ control ratio. B[a]P treatment increased the oxidation rate of several substrates that donate electrons at the level of all three coupling sites, either the ADP- or Ca2+-stimulated rates or those observed after ADP or Ca2+ exhaustion. However, the efficiency of energy coupling was maintained because both ADP/O and Ca2+/site ratios remained unchanged. The electron flow through NADH-oxidase, NADH-duroquinone reductase, NADH-juglone reductase, NADH-cytochrome c reductase, succinate-cytochrome c reductase, and cytochrome c oxidase was enhanced by B[a]P; however, succinate dehydrogenase activity was not affected. All these effects depended on the time post B[a]P administration, with a greater increase close to 48 h after administration of the carcinogen. The contents of cytochromes b, c1, and a + a3 from liver mitochondria, especially those isolated 48 h after B[a]P, were also significantly increased, although cytochrome c levels was just lightly increased 24 h after B[a]P treatment. These results suggest that B[a]P treatment stimulates mitochondrial respiration by increasing the level of several components of the mitochondrial respiratory chain. This may reflect mitochondrial adaptation to the cellular energy requirements of cell division in the neoplastic transformation process

  7. Effect of ageing on benzo[a]pyrene extractability in contrasting soils

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Luchun [CERAR-Centre for Environmental Risk Assessment and Remediation and Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), Building X, University of South Australia, Mawson Lakes, SA 5095 (Australia); Naidu, Ravi, E-mail: Ravi.Naidu@newcastle.edu.au [CERAR-Centre for Environmental Risk Assessment and Remediation and Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), Building X, University of South Australia, Mawson Lakes, SA 5095 (Australia); Liu, Yanju; Palanisami, Thavamani; Dong, Zhaomin; Mallavarapu, Megharaj [CERAR-Centre for Environmental Risk Assessment and Remediation and Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), Building X, University of South Australia, Mawson Lakes, SA 5095 (Australia); Semple, Kirk T. [Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom)

    2015-10-15

    Highlights: • In vitro assessment of B[a]P in contaminated soils using 4 different methods. • An exponential kinetic model fits well with the extractability data. • Fitting parameter and {sup 14}C residue correlates with key soil properties. • Fractionation of B[a]P was obtained based on extractability by extractants. - Abstract: Changes in benzo[a]pyrene (B[a]P) extractability over 160 days ageing in four contrasting soils varying in organic matter content and clay mineralogy were investigated using dichloromethane: acetone 1:1 (DCM/Ace), 60 mM hydroxypropyl-β-cyclodextrin (HPCD) solution, 1-butanol (BuOH) and Milli-Q water. The B[a]P extractability by the four methods decreased with ageing and a first-order exponential model could be used to describe the kinetics of release. Correlation of the kinetic rate constant with major soil properties showed a significant effect of clay and sand contents and pore volume fraction (<6 nm) on sequestration of the desorbable fraction (by HPCD) and the water-extractable fraction. Analysis of {sup 14}C-B[a]P in soils after ageing showed a limited loss of B[a]P via degradation. Fractionation of B[a]P pools associated with the soil matrix was analysed according to extractability of B[a]P by the different extraction methods. A summary of the different fractions is proposed for the illustration of the effect of ageing on different B[a]P-bound fractions in soils. This study provides a better understanding of the B[a]P ageing process associated with different fractions and also emphasises the extraction capacity of the different methods employed.

  8. The aryl hydrocarbon receptor nuclear translocator (Arnt) is required for tumor initiation by benzo[a]pyrene

    OpenAIRE

    Shi, Shengli; Yoon, Diana Y.; Hodge-Bell, Kimberly C.; Bebenek, Ilona G.; Whitekus, Michael J.; Zhang, Ruixue; Cochran, Alistair J.; Huerta-Yepez, Sara; Yim, Sun-Hee; Gonzalez, Frank J; Jaiswal, Anil K.; Hankinson, Oliver

    2009-01-01

    Benzo[a]pyrene (B[a]P) is a ligand for the aryl hydrocarbon receptor (Ahr). After binding ligand, Ahr dimerizes with the aryl hydrocarbon receptor nuclear translocator (Arnt) protein, and the dimer upregulates the transcription of Cyp1a1, Cyp1b1 and other enzymes involved in the metabolic activation of B[a]P. Arnt null mice die in utero. Mice in which Arnt deletion occurs constitutively in the epidermis die perinatally. In the current study, mice were developed in which the Arnt gene could be...

  9. Electrochemiluminescent Arrays for Cytochrome P450-Activated Genotoxicity Screening. DNA Damage from Benzo[a]pyrene Metabolites

    OpenAIRE

    Hvastkovs, Eli G.; So, Minjeong; Krishnan, Sadagopan; Bajrami, Besnik; Tarun, Maricar; Jansson, Ingela; Schenkman, John B.; Rusling, James F.

    2007-01-01

    Arrays suitable for genotoxicity screening are reported that generate metabolites from cytochrome P450 enzymes (CYPs) in thin-film spots. Array spots containing DNA, various human cyt P450s, and electrochemiluminescence (ECL) generating metallopolymer [Ru(bpy)2PVP10]2+ were exposed to H2O2 to activate the enzymes. ECL from all spots was visualized simultaneously using a CCD camera. Using benzo[a]pyrene as a test substrate, enzyme activity for producing DNA damage in the arrays was found in th...

  10. An extracellular Staphylococcus epidermidis polysaccharide: relation to Polysaccharide Intercellular Adhesin and its implication in phagocytosis

    Directory of Open Access Journals (Sweden)

    Spiliopoulou Anastasia I

    2012-05-01

    Full Text Available Abstract Background The skin commensal and opportunistic pathogen Staphylococcus epidermidis is a leading cause of hospital-acquired and biomaterial-associated infections. The polysaccharide intercellular adhesin (PIA, a homoglycan composed of β-1,6-linked N-acetylglucosamine residues, synthesized by enzymes encoded in icaADBC is a major functional factor in biofilm accumulation, promoting virulence in experimental biomaterial-associated S. epidermidis infection. Extracellular mucous layer extracts of S. epidermidis contain another major polysaccharide, referred to as 20-kDa polysaccharide (20-kDaPS, composed mainly out of glucose, N-acetylglucosamine, and being partially sulfated. 20-kDaPS antiserum prevents adhesion of S. epidermidis on endothelial cells and development of experimental keratitis in rabbits. Here we provide experimental evidence that 20-kDaPS and PIA represent distinct molecules and that 20-kDaPS is implicated in endocytosis of S. epidermidis bacterial cells by human monocyte-derived macrophages. Results Analysis of 75 clinical coagulase-negative staphylococci from blood-cultures and central venous catheter tips indicated that 20-kDaPS is expressed exclusively in S. epidermidis but not in other coagulase-negative staphylococcal species. Tn917-insertion in various locations in icaADBC in mutants M10, M22, M23, and M24 of S. epidermidis 1457 are abolished for PIA synthesis, while 20-kDaPS expression appears unaltered as compared to wild-type strains using specific anti-PIA and anti-20-kDaPS antisera. While periodate oxidation and dispersin B treatments abolish immuno-reactivity and intercellular adhesive properties of PIA, no abrogative activity is exerted towards 20-kDaPS immunochemical reactivity following these treatments. PIA polysaccharide I-containing fractions eluting from Q-Sepharose were devoid of detectable 20-kDaPS using specific ELISA. Preincubation of non-20-kDaPS-producing clinical strain with increasing amounts of

  11. MicroRNA-141 is upregulated in preeclamptic placentae and regulates trophoblast invasion and intercellular communication.

    Science.gov (United States)

    Ospina-Prieto, Stephanie; Chaiwangyen, Wittaya; Herrmann, Jörg; Groten, Tanja; Schleussner, Ekkehard; Markert, Udo R; Morales-Prieto, Diana M

    2016-06-01

    Preeclampsia (PE) is one of the leading causes of maternal and perinatal morbidity and mortality worldwide. Abnormal expression of microRNAs (miRNAs) occurs in several pregnancy diseases including PE. Placental trophoblast cells express a specific set of miRNAs which changes during pregnancy. These miRNAs can be released within extracellular vesicles (EVs) and mediate intercellular communication. miR-141 is a pregnancy-related miRNA which is expressed by trophoblast cells at increased levels in maternal plasma in the third trimester. We hypothesize that miR-141 is abnormally expressed in PE placentae, controls trophoblast, and immune cell functions and is involved in the intercellular communication between fetal trophoblast and maternal immune cells. Expression of miR-141 was analyzed by quantitative real-time PCR (qPCR) in normal and preeclamptic placentae and in 2 different trophoblastic cell lines, JEG-3 and HTR-8/SVneo. Changes in JEG-3 and HTR-8/SVneo cell proliferation and invasion were investigated after miR-141 inhibition and overexpression by MTS-, BrdU-, and Matrigel assays. EVs from miR-141 transfected cells were isolated from supernatants and characterized by NanoSight analysis and qPCR. Proliferation of Jurkat T cells and invasion of HTR-8/SVneo cells were investigated after treatment with EVs containing different miR-141 levels. miR-141 expression was higher in placentae from PE patients compared with those from normal pregnancies. miR-141 inhibition in trophoblastic cells resulted in decreased cell viability and reduced invasion capability. After transfection with miR-141-mimic, trophoblastic cells secreted EVs with increased miR-141 content. These vesicles did not exert effects on trophoblastic cell invasion but reduced Jurkat T cell proliferation. In conclusion, miR-141 regulates major functions of trophoblastic and immune cells. Trophoblast cells release EVs whose miRNA content can be modified by transfection of origin cells. Furthermore

  12. Antiproliferative Action of Conjugated Linoleic Acid on Human MCF-7 Breast Cancer Cells Mediated by Enhancement of Gap Junctional Intercellular Communication through Inactivation of NF-κB

    Directory of Open Access Journals (Sweden)

    Md. Abdur Rakib

    2013-01-01

    Full Text Available The major conjugated linoleic acid (CLA isomers, c9,t11-CLA and t10,c12-CLA, have anticancer effects; however, the exact mechanisms underlying these effects are unknown. Evidence suggests that reversal of reduced gap junctional intercellular communication (GJIC in cancer cells inhibits cell growth and induces cell death. Hence, we determined that CLA isomers enhance GJIC in human MCF-7 breast cancer cells and investigated the underlying molecular mechanisms. The CLA isomers significantly enhanced GJIC of MCF-7 cells at 40 μM concentration, whereas CLA inhibited cell growth and induced caspase-dependent apoptosis. CLA increased connexin43 (Cx43 expression both at the transcriptional and translational levels. CLA inhibited nuclear factor-κB (NF-κB activity and enhanced reactive oxygen species (ROS generation. No significant difference was observed in the efficacy of c9,t11-CLA and t10,c12-CLA. These results suggest that the anticancer effect of CLA is associated with upregulation of GJIC mediated by enhanced Cx43 expression through inactivation of NF-κB and generation of ROS in MCF-7 cells.

  13. Determination of Benzo(a)pyrene in Malaysian commercialized coffee powder using solid phase extraction and gas chromatography

    International Nuclear Information System (INIS)

    Roasting is a critical process in coffee production as it enables the development of flavor and aroma. Benzo[a]pyrene (BaP) is a non desirable product of incomplete combustion at temperatures between 300 and 600 degree Celsius and may be produced during roasting step. In this study, selected samples of roasted coffee powder were analysed for BaP. Extraction of BaP was achieved using C18 solid phase extraction (SPE) prior to analysis by gas chromatography. Calibration curve prepared with concentrations ranged between 3 - 50 ppm showed good linearity with r = 0.999. The limit of detection (LOD) was 0.25 ppm and the limit of quantification (LOQ) was 0.85 ppm. Recovery of BaP obtained from spiked sample (3 ppm) was 88.7 % with RSD (n=3) of 5.4 %. Benzo[a]pyrene was detected in all samples, at level ranging from 0.14 to 0.62 ppb. (author)

  14. Can crude oil toxicity on phytoplankton be predicted based on toxicity data on benzo(a)pyrene and naphthalene?

    Science.gov (United States)

    Ozhan, Koray; Bargu, Sibel

    2014-02-01

    Polycyclic aromatic hydrocarbons (PAHs), which are major components of crude oil, are responsible in large part for the toxicity of crude oil to phytoplankton. This study addressed the following question. Can reliable predictions of the aquatic toxicity of crude oil, a multi-component mixture, be described from toxicity data on individual PAH compounds? Naphthalene, the most abundant PAH compound, and benzo(a)pyrene, a highly toxic PAH compound, were selected as model compounds to quantify toxicity of crude oil on two phytoplankton species, Ditylum brightwellii and Heterocapsa triquetra, by analyzing the effects of different concentrations of these PAHs on growth rate. EC50 values suggested that the diatom D. brightwellii was more vulnerable to both toxicants than the dinoflagellate H. triquetra. However, a previous study, which investigated the impact of crude oil on the same two species, had opposite results. The differences in response from these phytoplankton species to naphthalene and benzo(a)pyrene toxicity compared to their response to crude oil suggest that they may not be solely used as surrogates to assess crude oil toxicity on phytoplankton. PMID:24352418

  15. [Isolation of highly-effective benzo[a]pyrene degrading strain and its degradation capacity].

    Science.gov (United States)

    Liu, Hai-Bin; Wang, Cui-Ping; Zhang, Zhi-Yuan; Xu, Wei; Hao, Zhi-Neng; Sun, Hong-Wen

    2011-09-01

    One new mycete, which could degrade high concentration (up to 100 mg/L) of benzo[a]pyrene (BaP) in liquid, was isolated from contaminated soil of Beijing Coking Plant by gradually increasing the concentration of BaP in mineral salt medium (MSM) in order to get new microorganism species for remediation of BaP contamination. The strain was identified as Lasiodiplodia theobromae, and its biodegradation ability in liquid was further investigated. The results showed that L. theobromae could utilize BaP as sole carbon and energy sources. The experiment was conducted for 10 days, and the biodegradation rate of BaP was 52.5% +/- 1.5%. Compared to Czapek's mineral medium, MSM was more suitable for L. theobromae, and biodegradation rate was 2.8 percent greater than that by using Czapek's mineral media after 10 days' cultivation. Potato-dextrose nutrient medium could accelrate the biodegradation in early stage, and biodegradation rate of BaP increased by 19.2 percent in the second day. However, the accelration was not significant in the latter period, biodegradation rate was only increased by 5.4 percent after 10 days' cultivation. L. theobromae could tolerate a wide pH range, with the optimum pH of 5. Addition of salicylic and sodium succinate enhanced the biodegradation rates by 6.2 percent and 4.2 percent, respectively, after 10 days' cultivation. Besides BaP, L. theobromae could also degrade high concentration (200 mg/L) of phenanthrene and pyrene, and the biodegradation rates were 70.0% +/- 1.0%, 59.2% +/- 3.2%, and 52.5% +/- 1.5% when they were single substrate and were 21.6% +/- 2.1%, 14.5% +/- 5.5%, and 11.9% +/- 2.2% when they existed in mixture, respectively. The biodegradation rate followed an order of phenanthrene > pyrene > BaP. The co-existence of the three substrates led a reduction in biodegradation. This study provides a new microorganism species for remediation of polycyclic aromatic hydrocarbons (PAHs) contamination in the environment. PMID:22165241

  16. Association of Intercellular Adhesion Molecule 1 (ICAM1 with Diabetes and Diabetic Nephropathy

    Directory of Open Access Journals (Sweden)

    Harvest F Gu

    2013-01-01

    Full Text Available Diabetes and diabetic nephropathy are complex diseases affected by genetic and environmental factors. Identification of the susceptibility genes and investigation of their roles may provide useful information for better understanding of the pathogenesis and for developing novel therapeutic approaches. Intercellular adhesion molecule 1 (ICAM1 is a cell surface glycoprotein expressed on endothelial cells and leukocytes in the immune system. The ICAM1 gene is located on chromosome 19p13 within the linkage region of diabetes. In the recent years, accumulating reports have implicated that genetic polymorphisms in the ICAM1 gene are associated with diabetes and diabetic nephropathy. Serum ICAM1 levels in diabetes patients and the icam1 gene expression in kidney tissues of diabetic animals are increased compared to the controls. Therefore, ICAM1 may play a role in the development of diabetes and diabetic nephropathy. In this review, we present genomic structure, variation and regulation of the ICAM1 gene, summarized genetic and biological studies of this gene in diabetes and diabetic nephropathy and discussed about the potential application using ICAM1 as a biomarker and target for prediction and treatment of diabetes and diabetic nephropathy.

  17. A human/mouse chimeric monoclonal antibody against intercellular adhesion molecule-1 for tumor radioimmunoimaging

    Energy Technology Data Exchange (ETDEWEB)

    Yamamura, Miyuki; Hinoda, Yuji; Sasaki, Shigeru; Tsujisaki, Masayuki; Imai, Kohzoh [Sapporo Medical Univ. (Japan); Oriuchi, Noboru; Endo, Keigo

    1996-04-01

    A mouse-human chimeric antibody for intercellular adhesion molecule-1 (ICAM-1) was established by using heavy chain loss mouse mutant hybridoma and human immunoglobulin expression vector. The HA58 hybridoma secreted anti-ICAM-1 monoclonal antibody (MoAb) (IgG1,{kappa}). The gene of the mouse variable region of heavy chain was amplified and cloned by the polymerase chain reaction technique directly from the HA58 hybridoma RNA. The variable region of heavy chain was joined with an expression vector which contains human {gamma}1 constant gene. The expression vector was transfected into heavy chain loss mutant cells HA58-7, which produced only murine immunoglobulin light chains. The resultant chimeric MoAb HA58, chHA58, retained full-binding reactivity to ICAM-1 compared with murine HA58 parental antibody. The chimeric MoAb chHA58 showed little antibody dependent cell-mediated cytotoxic activity against cultured tumor cells. Biodistribution studies with {sup 99m}Tc-labeled chHA58 in nude mice bearing human gastric carcinoma JRST cells, demonstrated that the tumor-blood ratio was 1.55 at 18 h after injection, when the tumors were clearly visible in gamma scintigraphy. These data suggest that chHA58 may be of practical use for radioimmunoimaging of a wide variety of tumors. (author).

  18. Gap junction as an intercellular glue: Emerging roles in cancer EMT and metastasis.

    Science.gov (United States)

    Mao, Xiao-Yuan; Li, Qiu-Qi; Gao, Yuan-Feng; Zhou, Hong-Hao; Liu, Zhao-Qian; Jin, Wei-Lin

    2016-10-10

    Metastasis is a common phenomenon in the progression and dissemination of cancer. It is estimated that metastasis accounts for 90% cancer-related mortality. Although the formation of tumor metastasis is relatively well understood, the underlying molecular mechanisms responsible for the emergence of aggressive cancer phenotype are still elusive. Figuring out the mechanisms by which cancer cells evade from the tumor is beneficial for obtaining novel and effectively therapeutic approaches. Primary tumors are composed of various subpopulations of cells with heterogeneous metastatic characteristics and the occurrence of metastatic dissemination is mainly dependent upon the interactions between tumor and the surrounding microenvironment. Tumor microenvironment (TME) such as extracellular matrix, macrophages, fibroblasts, stem cells and endothelial cells can orchestrate events critical to tumor evolution toward metastasis. GJ serves as an important communication between tumor cells and stromal cells. Increased GJs coupling blocks metastatic potential in some cancer animal models such as breast cancer and melanoma. Besides, epithelial-to-mesenchymal transition (EMT) is also a crucial step in the metastatic process and there are signs that GJs contribute to cell adhesion and migration (the pathological feature of EMT) in breast cancer. Therefore, we propose that GJ serves as an intercellular glue to suppress EMT and cancer metastasis. PMID:27490999

  19. Multicellular compartmentation of catharanthus roseus alkaloid biosynthesis predicts intercellular translocation of a pathway intermediate

    Science.gov (United States)

    St-Pierre, B; Vazquez-Flota, FA; De Luca V

    1999-01-01

    In situ RNA hybridization and immunocytochemistry were used to establish the cellular distribution of monoterpenoid indole alkaloid biosynthesis in Madagascar periwinkle (Catharanthus roseus). Tryptophan decarboxylase (TDC) and strictosidine synthase (STR1), which are involved in the biosynthesis of the central intermediate strictosidine, and desacetoxyvindoline 4-hydroxylase (D4H) and deacetylvindoline 4-O-acetyltransferase (DAT), which are involved in the terminal steps of vindoline biosynthesis, were localized. tdc and str1 mRNAs were present in the epidermis of stems, leaves, and flower buds, whereas they appeared in most protoderm and cortical cells around the apical meristem of root tips. In marked contrast, d4h and dat mRNAs were associated with the laticifer and idioblast cells of leaves, stems, and flower buds. Immunocytochemical localization for TDC, D4H, and DAT proteins confirmed the differential localization of early and late stages of vindoline biosynthesis. Therefore, we concluded that the elaboration of the major leaf alkaloids involves the participation of at least two cell types and requires the intercellular translocation of a pathway intermediate. A basipetal gradient of expression in maturing leaves also was shown for all four genes by in situ RNA hybridization studies and by complementary studies with dissected leaves, suggesting that expression of the vindoline pathway occurs transiently during early leaf development. These results partially explain why attempts to produce vindoline by cell culture technology have failed. PMID:10330473

  20. Transient suppression of gap junctional intercellular communication after exposure to 100-nanosecond pulsed electric fields.

    Science.gov (United States)

    Steuer, Anna; Schmidt, Anke; Labohá, Petra; Babica, Pavel; Kolb, Juergen F

    2016-12-01

    Gap junctional intercellular communication (GJIC) is an important mechanism that is involved and affected in many diseases and injuries. So far, the effect of nanosecond pulsed electric fields (nsPEFs) on the communication between cells was not investigated. An in vitro approach is presented with rat liver epithelial WB-F344 cells grown and exposed in a monolayer. In order to observe sub-lethal effects, cells were exposed to pulsed electric fields with a duration of 100ns and amplitudes between 10 and 20kV/cm. GJIC strongly decreased within 15min after treatment but recovered within 24h. Gene expression of Cx43 was significantly decreased and associated with a reduced total amount of Cx43 protein. In addition, MAP kinases p38 and Erk1/2, involved in Cx43 phosphorylation, were activated and Cx43 became hyperphosphorylated. Immunofluorescent staining of Cx43 displayed the disassembly of gap junctions. Further, a reorganization of the actin cytoskeleton was observed whereas tight junction protein ZO-1 was not significantly affected. All effects were field- and time-dependent and most pronounced within 30 to 60min after treatment. A better understanding of a possible manipulation of GJIC by nsPEFs might eventually offer a possibility to develop and improve treatments.

  1. Transient changes in intercellular protein variability identify sources of noise in gene expression.

    Science.gov (United States)

    Singh, Abhyudai

    2014-11-01

    Protein levels differ considerably between otherwise identical cells, and these differences significantly affect biological function and phenotype. Previous work implicated various noise mechanisms that drive variability in protein copy numbers across an isogenic cell population. For example, transcriptional bursting of mRNAs has been shown to be a major source of noise in the expression of many genes. Additional expression variability, referred to as extrinsic noise, arises from intercellular variations in mRNA transcription and protein translation rates attributed to cell-to-cell differences in cell size, abundance of ribosomes, etc. We propose a method to determine the magnitude of different noise sources in a given gene of interest. The method relies on blocking transcription and measuring changes in protein copy number variability over time. Our results show that this signal has sufficient information to quantify both the extent of extrinsic noise and transcription bursting in gene expression. Moreover, if the mean mRNA count is known, then the relative contributions of transcription versus translation rate fluctuations to extrinsic noise can also be determined. In summary, our study provides an easy-to-implement method for characterizing noisy protein expression that complements existing techniques for studying stochastic dynamics of genetic circuits.

  2. Purification and Evaluation of Polysaccharide Intercellular Adhesion (PIA) Antigen from Staphylococcus epidermidis.

    Science.gov (United States)

    Mirzaei, Bahman; Moosavi, Seyed Fazlollah; Babaei, Ryhane; Siadat, Seyed Davar; Vaziri, Farzam; Shahrooei, Mohammad

    2016-11-01

    The polysaccharide intercellular adhesin (PIA) confers major functional effects in biofilm formation, which bears an important role in the pathogenicity of Staphylococcus epidermidis. Following the identification of biofilm-forming strains by biochemical and molecular methods, isogenic strain was prepared and in vitro biofilm formation assay was performed consequently. By parallel analysis of both the PIA-positive and PIA-negative strains using size exclusion chromatography by Fast protein liquid chromatography (FPLC) method, the respective PIA was purified. Recovered PIA was examined using colorimetric and hemagglutination assays. Finally, the recovered PIA was analyzed using Fourier-transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy methods. By the parallel purification process and comparison of the obtained graphs from the FPLC detector, fractions near the void volume were determined as PIA. The colorimetric and hemagglutination assays were applied and the content of carbohydrates (hexose = 620 µg/ml, hexosamine = 5700 µg/ml and ketoses = 170 µg/ml) and hemagglutination titer (1:128) in recovered polysaccharide were determined. This study shows that PIA has a significant role in the biofilm formation in S. epidermidis strains. The recovered polysaccharide and its molecular weight were analyzed within the near void volume of the utilized column. PMID:27460584

  3. Decreased pulmonary inflammation after ethanol exposure and burn injury in intercellular adhesion molecule-1 knockout mice.

    Science.gov (United States)

    Bird, Melanie D; Morgan, Michelle O; Ramirez, Luis; Yong, Sherri; Kovacs, Elizabeth J

    2010-01-01

    Clinical and laboratory evidence suggests that alcohol consumption dysregulates immune function. Burn patients who consume alcohol before their injuries demonstrate higher rates of morbidity and mortality, including acute respiratory distress syndrome, than patients without alcohol at the time of injury. Our laboratory observed higher levels of proinflammatory cytokines and leukocyte infiltration in the lungs of mice after ethanol exposure and burn injury than with either insult alone. To understand the mechanism of the increased pulmonary inflammatory response in mice treated with ethanol and burn injury, we investigated the role of intercellular adhesion molecule (ICAM)-1. Wild-type and ICAM-1 knockout (KO) mice were treated with vehicle or ethanol and subsequently given a sham or burn injury. Twenty-four hours postinjury, lungs were harvested and analyzed for indices of inflammation. Higher numbers of neutrophils were observed in the lungs of wild-type mice after burn and burn with ethanol treatment. This increase in pulmonary inflammatory cell accumulation was significantly lower in the KO mice. In addition, levels of KC, interleukin-1beta, and interleukin-6 in the lung were decreased in the ICAM-1 KO mice after ethanol exposure and burn injury. Interestingly, no differences were observed in serum or lung tissue content of soluble ICAM-1 24 hours postinjury. These data suggest that upregulation of adhesion molecules such as ICAM-1 on the vascular endothelium may play a critical role in the excessive inflammation seen after ethanol exposure and burn injury.

  4. Drosophila wing imaginal discs respond to mechanical injury via slow InsP3R-mediated intercellular calcium waves

    Science.gov (United States)

    Restrepo, Simon; Basler, Konrad

    2016-08-01

    Calcium signalling is a highly versatile cellular communication system that modulates basic functions such as cell contractility, essential steps of animal development such as fertilization and higher-order processes such as memory. We probed the function of calcium signalling in Drosophila wing imaginal discs through a combination of ex vivo and in vivo imaging and genetic analysis. Here we discover that wing discs display slow, long-range intercellular calcium waves (ICWs) when mechanically stressed in vivo or cultured ex vivo. These slow imaginal disc intercellular calcium waves (SIDICs) are mediated by the inositol-3-phosphate receptor, the endoplasmic reticulum (ER) calcium pump SERCA and the key gap junction component Inx2. The knockdown of genes required for SIDIC formation and propagation negatively affects wing disc recovery after mechanical injury. Our results reveal a role for ICWs in wing disc homoeostasis and highlight the utility of the wing disc as a model for calcium signalling studies.

  5. Drosophila wing imaginal discs respond to mechanical injury via slow InsP3R-mediated intercellular calcium waves.

    Science.gov (United States)

    Restrepo, Simon; Basler, Konrad

    2016-08-09

    Calcium signalling is a highly versatile cellular communication system that modulates basic functions such as cell contractility, essential steps of animal development such as fertilization and higher-order processes such as memory. We probed the function of calcium signalling in Drosophila wing imaginal discs through a combination of ex vivo and in vivo imaging and genetic analysis. Here we discover that wing discs display slow, long-range intercellular calcium waves (ICWs) when mechanically stressed in vivo or cultured ex vivo. These slow imaginal disc intercellular calcium waves (SIDICs) are mediated by the inositol-3-phosphate receptor, the endoplasmic reticulum (ER) calcium pump SERCA and the key gap junction component Inx2. The knockdown of genes required for SIDIC formation and propagation negatively affects wing disc recovery after mechanical injury. Our results reveal a role for ICWs in wing disc homoeostasis and highlight the utility of the wing disc as a model for calcium signalling studies.

  6. Intercellular transfer of P-glycoprotein in human blood-brain barrier endothelial cells is increased by histone deacetylase inhibitors

    OpenAIRE

    Andreas Noack; Sandra Noack; Manuela Buettner; Naim, Hassan Y.; Wolfgang Löscher

    2016-01-01

    The blood–brain barrier (BBB) controls the entry of compounds into the brain, thereby regulating brain homeostasis. Efflux transporters such as P-glycoprotein (Pgp) significantly contribute to BBB function. Multiple signaling pathways modulate the expression and activity of Pgp in response to xenobiotics and disease. A non-genetic way of intercellular transfer of Pgp occurs in cancer cells, but whether this also occurs in non-cancer cells such as endothelial cells that form the BBB is not kno...

  7. Exposure to phthalates affects calcium handling and intercellular connectivity of human stem cell-derived cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Nikki Gillum Posnack

    Full Text Available The pervasive nature of plastics has raised concerns about the impact of continuous exposure to plastic additives on human health. Of particular concern is the use of phthalates in the production of flexible polyvinyl chloride (PVC products. Di-2-ethylhexyl-phthalate (DEHP is a commonly used phthalate ester plasticizer that imparts flexibility and elasticity to PVC products. Recent epidemiological studies have reported correlations between urinary phthalate concentrations and cardiovascular disease, including an increased risk of high blood pressure and coronary risk. Yet, there is little direct evidence linking phthalate exposure to adverse effects in human cells, including cardiomyocytes.The effect of DEHP on calcium handling was examined using monolayers of gCAMP3 human embryonic stem cell-derived cardiomyocytes, which contain an endogenous calcium sensor. Cardiomyocytes were exposed to DEHP (5 - 50 μg/mL, and calcium transients were recorded using a Zeiss confocal imaging system. DEHP exposure (24 - 72 hr had a negative chronotropic and inotropic effect on cardiomyocytes, increased the minimum threshold voltage required for external pacing, and modified connexin-43 expression. Application of Wy-14,643 (100 μM, an agonist for the peroxisome proliferator-activated receptor alpha, did not replicate DEHP's effects on calcium transient morphology or spontaneous beating rate.Phthalates can affect the normal physiology of human cardiomyocytes, including DEHP elicited perturbations in cardiac calcium handling and intercellular connectivity. Our findings call for additional studies to clarify the extent by which phthalate exposure can alter cardiac function, particularly in vulnerable patient populations who are at risk for high phthalate exposure.

  8. Intercellular Variability in Protein Levels from Stochastic Expression and Noisy Cell Cycle Processes

    Science.gov (United States)

    Soltani, Mohammad; Vargas-Garcia, Cesar A.; Antunes, Duarte; Singh, Abhyudai

    2016-01-01

    Inside individual cells, expression of genes is inherently stochastic and manifests as cell-to-cell variability or noise in protein copy numbers. Since proteins half-lives can be comparable to the cell-cycle length, randomness in cell-division times generates additional intercellular variability in protein levels. Moreover, as many mRNA/protein species are expressed at low-copy numbers, errors incurred in partitioning of molecules between two daughter cells are significant. We derive analytical formulas for the total noise in protein levels when the cell-cycle duration follows a general class of probability distributions. Using a novel hybrid approach the total noise is decomposed into components arising from i) stochastic expression; ii) partitioning errors at the time of cell division and iii) random cell-division events. These formulas reveal that random cell-division times not only generate additional extrinsic noise, but also critically affect the mean protein copy numbers and intrinsic noise components. Counter intuitively, in some parameter regimes, noise in protein levels can decrease as cell-division times become more stochastic. Computations are extended to consider genome duplication, where transcription rate is increased at a random point in the cell cycle. We systematically investigate how the timing of genome duplication influences different protein noise components. Intriguingly, results show that noise contribution from stochastic expression is minimized at an optimal genome-duplication time. Our theoretical results motivate new experimental methods for decomposing protein noise levels from synchronized and asynchronized single-cell expression data. Characterizing the contributions of individual noise mechanisms will lead to precise estimates of gene expression parameters and techniques for altering stochasticity to change phenotype of individual cells. PMID:27536771

  9. Transferring intercellular signals and traits between cancer cells: extracellular vesicles as "homing pigeons".

    Science.gov (United States)

    Cesi, Giulia; Walbrecq, Geoffroy; Margue, Christiane; Kreis, Stephanie

    2016-01-01

    Extracellular vesicles are cell-derived vesicles, which can transport various cargos out of cells. From their cell of origin, the content molecules (proteins, non-coding RNAs including miRNAs, DNA and others) can be delivered to neighboring or distant cells and as such extracellular vesicles can be regarded as vehicles of intercellular communication or "homing pigeons". Extracellular vesicle shuttling is able to actively modulate the tumor microenvironment and can partake in tumor dissemination. In various diseases, including cancer, levels of extracellular vesicle secretion are altered resulting in different amounts and/or profiles of detectable vesicular cargo molecules and these distinct content profiles are currently being evaluated as biomarkers. Apart from their potential as blood-derived containers of specific biomarkers, the transfer of extracellular vesicles to surrounding cells also appears to be involved in the propagation of phenotypic traits. These interesting properties have put extracellular vesicles into the focus of many recent studies.Here we review findings on the involvement of extracellular vesicles in transferring traits of cancer cells to their surroundings and briefly discuss new data on oncosomes, a larger type of vesicle. A pressing issue in cancer treatment is rapidly evolving resistance to many initially efficient drug therapies. Studies investigating the role of extracellular vesicles in this phenomenon together with a summary of the technical challenges that this field is still facing, are also presented. Finally, emerging areas of research such as the analysis of the lipid composition on extracellular vesicles and cutting-edge techniques to visualise the trafficking of extracellular vesicles are discussed. PMID:27282631

  10. Point mutation in the mouse P2X7 receptor affects intercellular calcium waves in astrocytes

    Directory of Open Access Journals (Sweden)

    Sylvia O Suadicani

    2009-04-01

    Full Text Available Purinergic P2 receptors and gap junctions are two groups of proteins involved in the transmission of ICWs (intercellular calcium waves) between astrocytes. The extent to which ICWs spread among these glial cells depends on the amount of ATP released, which can occur through membrane channels, as well as other pathways. Our previous studies have shown that the pore-forming P2X7R (P2X7 receptor) contributes to the amplification of ICW spread by providing sites of ATP release through Panx1 (Pannexin1) channels. To gain insight into the signal transduction events mediating this response we compared the properties of the P2X7R–Panx1 complex in astrocytes from a mouse strain (C57Bl/6) containing a naturally occurring point mutation (P451L) in the C-terminus of the P2X7R to that of non-mutated receptors (Balb/C mice). Electrophysiological, biochemical, pharmacological and fluorescence imaging techniques revealed that the P451L mutation located in the SH3 domain (a Src tyrosine kinase-binding site) of the C-terminus of the P2X7R attenuates Panx1 currents, ATP release and the distance of ICW spread between astrocytes. Similar results were obtained when using the Src tyrosine inhibitor (PP2) and a membrane-permeant peptide spanning the P451L mutation of the P2X7R of the C57Bl6 astrocytes. These results support the participation of a tyrosine kinase of the Src family in the initial steps mediating the opening of Panx1 channels following P2X7R stimulation and in the transmission of calcium signals among astrocytes.

  11. INTERCELLULAR AND INTRACELLULAR TRAFFICKING OF NAD+ AND NAD+ PRECURSORS, INTERMEDIATE METABOLITES AND SIGNAL METABOLITES

    Directory of Open Access Journals (Sweden)

    Antonio De Flora

    2012-08-01

    Full Text Available Although being currently illustrated in Biochemistry textbooks, NAD+ metabolism is still largely undefined in its features. Specifically, enzymes involved in NAD+ biosynthesis and some of the enzymes involved in its utilization localize to distinct subcellular compartments of the same cell and, functionally, also to different cell types of the same organism. These findings lead to revolutionize current ideas. For instance, 1 NAD+ biosynthesis from several precursors (e.g., Nicotinamide, Nicotinic Acid, Nicotinamide mononucleotide, Nicotinamide riboside, Tryptophan, collectively defined Vit. B3 is a systemic yet segmentary process, whose individual steps may occur in different cells/tissues/organs. These activate a crosstalk via the exchange of intermediate metabolites in biological fluids and the eventual NAD+ biosynthesis takes place in selected cells able to utilize it in diverse, fundamental processes. Therefore, NAD+ metabolism is an organ- ismal process encompassing local events. 2 Utilization of NAD+ for regulation of cell functions involves the trafficking, both subcellular (autocrine and intercellular (paracrine, of signal-metabolites including NAD+ itself and NAD+-derived second messengers, e.g. Cyclic ADP-ribose and ADP-ribose. This hitherto unrecognized trafficking involves a complex in-terplay of ectoenzymes (e.g. CD38, plasmamembrane receptors and related signal transduction pathways, equilibrative and concentrative transporters, ion channels, whose outcome is the fine control of intracellular Ca2+ homeostasis and of Ca2+-dependent cell functions. Further elucidation of compartmentation of NAD+ and more extensive identification of its precursors/metabolites is expected to unveil at the mechanistic level a number of physiological and pathological processes, e.g. aging and age-related diseases.

  12. Intercellular adhesion molecule 1 promotes HIV-1 attachment but not fusion to target cells.

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    Naoyuki Kondo

    Full Text Available Incorporation of intercellular adhesion molecule 1 (ICAM-1 into HIV-1 particles is known to markedly enhance the virus binding and infection of cells expressing lymphocyte function-associated antigen-1 (LFA-1. At the same time, ICAM-1 has been reported to exert a less pronounced effect on HIV-1 fusion with lymphoid cells. Here we examined the role of ICAM-1/LFA-1 interactions in productive HIV-1 entry into lymphoid cells using a direct virus-cell fusion assay. ICAM-1 promoted HIV-1 attachment to cells in a temperature-dependent manner. It exerted a marginal effect on virus binding in the cold, but enhanced binding up to 4-fold at physiological temperature. ICAM-1-independent attachment in the cold was readily reversible upon subsequent incubation at elevated temperature, whereas ICAM-1-bearing particles were largely retained by cells. The better virus retention resulted in a proportional increase in HIV-1 internalization and fusion, suggesting that ICAM-1 did not specifically accelerate endocytosis or fusion steps. We also measured the rates of CD4 engagement, productive endocytosis and HIV-endosome fusion using specific fusion inhibitors. These rates were virtually independent of the presence of ICAM-1 in viral particles. Importantly, irrespective of the presence of ICAM-1, HIV-1 escaped from the low temperature block, which stopped virus endocytosis and fusion, much later than from a membrane-impermeant fusion inhibitor targeting surface-accessible particles. This result, along with the complete inhibition of HIV-1 fusion by a small molecule dynamin inhibitor, implies this virus enters lymphoid cells used in this study via endocytosis and that this pathway is not altered by the viral ICAM-1. Our data highlight the role of ICAM-1 in stabilizing the HIV-1 attachment to LFA-1 expressing cells, which leads to a proportional enhancement of the receptor-mediated uptake and fusion with endosomes.

  13. The lateral intercellular space as osmotic coupling compartment in isotonic transport.

    Science.gov (United States)

    Larsen, E H; Willumsen, N J; Møbjerg, N; Sørensen, J N

    2009-01-01

    Solute-coupled water transport and isotonic transport are basic functions of low- and high-resistance epithelia. These functions are studied with the epithelium bathed on the two sides with physiological saline of similar composition. Hence, at transepithelial equilibrium water enters the epithelial cells from both sides, and with the reflection coefficient of tight junction being larger than that of the interspace basement membrane, all of the water leaves the epithelium through the interspace basement membrane. The common design of transporting epithelia leads to the theory that an osmotic coupling of water absorption to ion flow is energized by lateral Na(+)/K(+) pumps. We show that the theory accounts quantitatively for steady- and time dependent states of solute-coupled fluid uptake by toad skin epithelium. Our experimental results exclude definitively three alternative theories of epithelial solute-water coupling: stoichiometric coupling at the molecular level by transport proteins like SGLT1, electro-osmosis and a 'junctional fluid transfer mechanism'. Convection-diffusion out of the lateral space constitutes the fundamental problem of isotonic transport by making the emerging fluid hypertonic relative to the fluid in the lateral intercellular space. In the Na(+) recirculation theory the 'surplus of solutes' is returned to the lateral space via the cells energized by the lateral Na(+)/K(+) pumps. We show that this theory accounts quantitatively for isotonic and hypotonic transport at transepithelial osmotic equilibrium as observed in toad skin epithelium in vitro. Our conclusions are further developed for discussing their application to solute-solvent coupling in other vertebrate epithelia such as small intestine, proximal tubule of glomerular kidney and gallbladder. Evidence is discussed that the Na(+) recirculation theory is not irreconcilable with the wide range of metabolic cost of Na(+) transport observed in fluid-transporting epithelia. PMID:18983444

  14. Human platelets express CAR with localization at the sites of intercellular interaction

    Directory of Open Access Journals (Sweden)

    Othman Maha

    2011-09-01

    Full Text Available Abstract Adenovirus has a wide tissue tropism. The virus attaches to the surface of cells via the fiber protein knob binding to the Coxsackie and Adenovirus receptor known as CAR. Virus entry inside cells is facilitated by integrins αVβ3 and αVβ5. Mice platelets are shown to be the predominant Ad binding blood cell type and the virus is documented inside platelets. CAR was identified on human platelets in one study yet contradicted in another. The presence of CAR appears to be the most reasonable initial step for virus entry into platelets and is a key to the understanding of platelet adenovirus interaction. This study aimed to re investigate the presence of CAR on human platelets. Platelets were tested by indirect immune-fluorescence using rabbit H-300 polyclonal anti-CAR antibody and goat anti-rabbit IgG F(ab'2 Texas Red antibodies, alongside with CAR positive and negative controls. Platelets were found to express CAR on their surface and in contrast to the previous study only 3.5 ± 1.9% of the tested platelets did express CAR. In addition, CAR was seen within intracellular aggregates localized at the sites of cell-cell contacts indicating that CAR expression might be upregulated in response to platelet stimulation. We confirm the presence of CAR on human platelets, we provide explanation to some of the discrepancies in this regards and we add that this receptor is localized at the sites of intercellular interaction.

  15. Lipopolysaccharide Binding Protein, Soluble-Intercellular Adhesion Molecule-1, Procalcitonin, and Protein C Activity and Clinical Outcome in Systemic Inflammatory Response Syndrome (SIRS or Sepsis Patients

    Directory of Open Access Journals (Sweden)

    Dewi Muliaty

    2009-04-01

    Full Text Available BACKGROUND: Biochemical markers may be used in diagnosis, prognostic and monitoring treatment and therapy for sepsis patients. In this study we used Lipopolysacharide Binding Protein (LBP, serum-Intercellular Adhesion Molecule-1 (ICAM-1, Procalcitonin (PCT and protein C activity. LBP is related to lipopolysachharide or gram-negative bacterial endotoxin which bound to LBP and induced inflammatory response. ICAM-1 is associated with endothelial dysfunction in response to systemic inflammatory and septic condition. PCT increased in bacterial infection and in severe systemic inflammatory. Role of Protein C is protecting the intravascular system to systemic inflammation, sepsis and the concomitant intravascular coagulopathy. The aim of this study was to examine the associations between levels of serum LBP, sICAM-1, PCT, and protein C activity with the clinical outcome of SIRS or sepsis patients. METHODS: We included 19 post surgery patients with SIRS criteria from intensive care unit (ICU and evaluated the level of LBP serum with Chemiliuminescent Enzyme Immunoassay (Diagnostic Product Co., ICAM-1 with ELISA (R&D System, PCT with immunochromatography (BRAHMS, protein C activity with chromogenic method (Dade Behring. We performed the samples serially at the first admission of patients and after 72 hours. Data were analysed by non-parametric with Wilcoxon test and Mann-Whitney test. Correlation study between biomarkers calculated by Kendall’s tau and Spearman’s rho. RESULTS: Of 19 patients, 9 (47,4% died and 10 (52,6% surviving. The level of LBP serum decreased after 72 hours in surviving-sepsis patients, and increased in nonsurviving sepsis patients with significant different levels at 72 hours examination (p0.05. In all patients were found high level of PCT serum since the first admission examination, decreasing levels were occurred significantly in surviving patients after 72 hours (p0.05 both in surviving and non-surviving patients. CONCLUSIONS

  16. Benzo(a)pyrene accumulation in soils of technogenic emission zone by subcritical water extraction method

    Science.gov (United States)

    Sushkova, Svetlana; Minkina, Tatiana; Kizilkaya, Ridvan; Mandzhieva, Saglara; Batukaev, Abdulmalik; Bauer, Tatiana; Gulser, Coskun

    2016-04-01

    The purpose of research is the assessment of main marker of polycyclic aromatic hydrocarbons contamination, benzo[a]pyrene (BaP) content in soils of emission zone of the power complex plant in soils with use of ecologically clean and effective subcritical water extraction method. Studies were conducted on the soils of monitoring plots subjected to Novocherkassk Power Plant emissions from burning coal. In 2000, monitoring plots were established at different distances from the NPS (1.0-20.0 km). Soil samples for the determination of soil properties and the contents of BaP were taken from a depth of 0-20 cm. The soil cover in the region under study consisted of ordinary chernozems, meadow-chernozemic soils, and alluvial meadow soils. This soil revealed the following physical and chemical properties: Corg-3.1-5.0%, pH-7.3-7.6, ECE-31.2-47.6 mmol(+)/100g; CaCO3-0.2-1.0%, the content of physical clay - 51-67% and clay - 3-37%. BaP extraction from soils was carried out by a subcritical water extraction method. Subcritical water extraction of BaP from soil samples was conducted in a specially developed extraction cartridge made of stainless steel and equipped with screw-on caps at both ends. It was also equipped with a manometer that included a valve for pressure release to maintain an internal pressure of 100 atm. The extraction cartridge containing a sample and water was placed into an oven connected to a temperature regulator under temperature 250oC and pressure 60 atm. The BaP concentration in the acetonitrile extract was determined by HPLC. The efficiency of BaP extraction from soil was determined using a matrix spike. The main accumulation of pollutant in 20 cm layer of soils is noted directly in affected zone on the plots situated at 1.2, 1.6, 5.0, 8.0 km from emission source in the direction of prevailing winds. The maximum quantity of a pollutant was founded in the soil of the plot located mostly close to a source of pollution in the direction of prevailing winds

  17. Mapping intercellular CO2 mole fraction (Ci) in rosa rubiginosa leaves fed with abscisic acid by using chlorophyll fluorescence imaging. Significance Of ci estimated from leaf gas exchange

    Science.gov (United States)

    Meyer; Genty

    1998-03-01

    Imaging of photochemical yield of photosystem II (PSII) computed from leaf chlorophyll fluorescence images and gas-exchange measurements were performed on Rosa rubiginosa leaflets during abscisic acid (ABA) addition. In air ABA induced a decrease of both the net CO2 assimilation (An) and the stomatal water vapor conductance (gs). After ABA treatment, imaging in transient nonphotorespiratory conditions (0.1% O2) revealed a heterogeneous decrease of PSII photochemical yield. This decline was fully reversed by a transient high CO2 concentration (7400 mol mol-1) in the leaf atmosphere. It was concluded that ABA primarily affected An by decreasing the CO2 supply at ribulose-1,5-bisphosphate carboxylase/oxygenase. Therefore, the An versus intercellular mole fraction (Ci) relationship was assumed not to be affected by ABA, and images of Ci and gs were constructed from images of PSII photochemical yield under nonphotorespiratory conditions. The distribution of gs remained unimodal following ABA treatment. A comparison of calculations of Ci from images and gas exchange in ABA-treated leaves showed that the overestimation of Ci estimated from gas exchange was only partly due to heterogeneity. This overestimation was also attributed to the cuticular transpiration, which largely affects the calculation of the leaf conductance to CO2, when leaf conductance to water is low. PMID:9501127

  18. Cocaine-associated retiform purpura: a C5b-9-mediated microangiopathy syndrome associated with enhanced apoptosis and high levels of intercellular adhesion molecule-1 expression.

    Science.gov (United States)

    Magro, Cynthia M; Wang, Xuan

    2013-10-01

    Cocaine-associated retiform purpura is a recently described entity characterized by striking hemorrhagic necrosis involving areas of skin associated with administration of cocaine. Levamisole, an adulterant in cocaine, has been suggested as the main culprit pathogenetically. Four cases of cocaine-associated retiform purpura were encountered in the dermatopathology practice of C. M. Magro. The light microscopic findings were correlated with immunohistochemical and immunofluorescence studies. All 4 cases showed a very striking thrombotic diathesis associated with intravascular macrophage accumulation. Necrotizing vasculitis was noted in 1 case. Striking intercellular adhesion molecule-1 (ICAM-1)/CD54 expression in vessel wall along with endothelial expression of caspase 3 and extensive vascular C5b-9 deposition was observed in all biopsies examined. Cocaine-induced retiform purpura is a C5b-9-mediated microvascular injury associated with enhanced apoptosis and prominent vascular expression of ICAM-1, all of which have been shown in prior in vitro and in vivo murine models to be a direct effect of cocaine metabolic products. Antineutrophilic cytoplasmic antibody and antiphospholipid antibodies are likely the direct sequelae of the proapoptotic microenvironment. The inflammatory vasculitic lesion could reflect the downstream end point reflective of enhanced ICAM-1 expression and the development of antineutrophilic cytoplasmic antibody. Levamisole likely works synergistically with cocaine in the propagation of this syndromic complex. PMID:23392134

  19. Evolution of Microbial Quorum Sensing to Human Global Quorum Sensing: An Insight into How Gap Junctional Intercellular Communication Might Be Linked to the Global Metabolic Disease Crisis.

    Science.gov (United States)

    Trosko, James E

    2016-01-01

    The first anaerobic organism extracted energy for survival and reproduction from its source of nutrients, with the genetic means to ensure protection of its individual genome but also its species survival. While it had a means to communicate with its community via simple secreted molecules ("quorum sensing"), the eventual shift to an aerobic environment led to multi-cellular metazoan organisms, with evolutionary-selected genes to form extracellular matrices, stem cells, stem cell niches, and a family of gap junction or "connexin" genes. These germinal and somatic stem cells responded to extracellular signals that triggered intra-cellular signaling to regulate specific genes out of the total genome. These extra-cellular induced intra-cellular signals also modulated gap junctional intercellular communication (GJIC) in order to regulate the new cellular functions of symmetrical and asymmetrical cell division, cell differentiation, modes of cell death, and senescence. Within the hierarchical and cybernetic concepts, differentiated by neurons organized in the brain of the Homo sapiens, the conscious mind led to language, abstract ideas, technology, myth-making, scientific reasoning, and moral decision-making, i.e., the creation of culture. Over thousands of years, this has created the current collision between biological and cultural evolution, leading to the global "metabolic disease" crisis. PMID:27314399

  20. Evolution of Microbial Quorum Sensing to Human Global Quorum Sensing: An Insight into How Gap Junctional Intercellular Communication Might Be Linked to the Global Metabolic Disease Crisis.

    Science.gov (United States)

    Trosko, James E

    2016-01-01

    The first anaerobic organism extracted energy for survival and reproduction from its source of nutrients, with the genetic means to ensure protection of its individual genome but also its species survival. While it had a means to communicate with its community via simple secreted molecules ("quorum sensing"), the eventual shift to an aerobic environment led to multi-cellular metazoan organisms, with evolutionary-selected genes to form extracellular matrices, stem cells, stem cell niches, and a family of gap junction or "connexin" genes. These germinal and somatic stem cells responded to extracellular signals that triggered intra-cellular signaling to regulate specific genes out of the total genome. These extra-cellular induced intra-cellular signals also modulated gap junctional intercellular communication (GJIC) in order to regulate the new cellular functions of symmetrical and asymmetrical cell division, cell differentiation, modes of cell death, and senescence. Within the hierarchical and cybernetic concepts, differentiated by neurons organized in the brain of the Homo sapiens, the conscious mind led to language, abstract ideas, technology, myth-making, scientific reasoning, and moral decision-making, i.e., the creation of culture. Over thousands of years, this has created the current collision between biological and cultural evolution, leading to the global "metabolic disease" crisis.

  1. EROD activity and genotoxicity in the seabob shrimp Xiphopenaeus kroyeri exposed to benzo[a]pyrene (BaP) concentrations.

    Science.gov (United States)

    da Silva Rocha, Arthur José; Gomes, Vicente; Rocha Passos, Maria José de Arruda Campos; Hasue, Fabio Matsu; Alves Santos, Thaís Cruz; Bícego, Márcia Caruso; Taniguchi, Satie; Van Ngan, Phan

    2012-11-01

    Seabob shrimp Xiphopenaeus kroyeri is a marine species that lives in shallow waters of coastal environments, often impacted by polycyclic aromatic hydrocarbons (PAH) pollution. In the present study, seabob shrimp were exposed for 96 h to benzo[a]pyrene (BaP) at the nominal concentrations of 100, 200, 400 and 800 microg-L(-1). Animals of the control groups were exposed either to clean water or to the BaP-carrier (DMSO). At the end of the exposures, muscle tissues were sampled for BaP uptake assessment and hepatopancreas and hemolymph for EROD enzyme activity and hemocytes DNA damage, respectively. EROD activity and DNA damage increased significantly as a function of BaP exposure concentrations. Significant correlations between BaP uptake and both EROD activity and DNA damage suggest that they can be used as suitable tools for integrated levels of study on the biomarkers of PAH exposure.

  2. Electrochemiluminescent Arrays for Cytochrome P450-Activated Genotoxicity Screening. DNA Damage from Benzo[a]pyrene Metabolites

    Science.gov (United States)

    Hvastkovs, Eli G.; So, Minjeong; Krishnan, Sadagopan; Bajrami, Besnik; Tarun, Maricar; Jansson, Ingela; Schenkman, John B.; Rusling, James F.

    2007-01-01

    Arrays suitable for genotoxicity screening are reported that generate metabolites from cytochrome P450 enzymes (CYPs) in thin-film spots. Array spots containing DNA, various human cyt P450s, and electrochemiluminescence (ECL) generating metallopolymer [Ru(bpy)2PVP10]2+ were exposed to H2O2 to activate the enzymes. ECL from all spots was visualized simultaneously using a CCD camera. Using benzo[a]pyrene as a test substrate, enzyme activity for producing DNA damage in the arrays was found in the order CYP1B1 > CYP1A2 > CYP1A1 > CYP2E1 > myoglobin, the same as the order of their metabolic activity. Thus, these arrays estimate the relative propensity of different enzymes to produce genotoxic metabolites. This is the first demonstration of ECL arrays for high-throughput in vitro genotoxicity screening. PMID:17261025

  3. Myeloperoxidase - 463A variant reduces benzo(a)pyrene diol epoxide DNA adducts in skin of coal tar treated patients

    Energy Technology Data Exchange (ETDEWEB)

    Rojas, M.; Godschalk, R.; Alexandrov, K.; Cascorbi, I.; Kriek, E.; Ostertag, J.; Van Schooten, F.J.; Bartsch, H. [German Cancer Research Center, Heidelberg (Germany). Div. of Toxicology & Cancer Risk Factors

    2001-07-01

    The skin of atopic dermatitis patients provides an excellent model to study the role of inflammation in benzo(a)pyrene (BaP) activation, since these individuals are often topically treated with ointments containing high concentrations of BaP. The authors determined, by HPLC with fluorescence detection, the BaP diol epoxide (BPDE)-DNA adduct levels in human skin after topical treatment with coal tar and their modulation by the -453G into A myeloperoxidase (MPO) polymorphism, which reduces MPO mRNA expression. The data show for the first time: (i) the in vivo formation of BPDE-DNA adducts in human skin treated with coal tar; (ii) that the MPO-463AA/AG genotype reduced BPDE-DNA adduct levels in human skin.

  4. Expression of intercellular adhesion molecule-1and HLA-DR antigens in uveitis

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    目的:研究细胞间粘附分子-1(intellular adhesion molecule-1,ICAM-1)和人体组织相关抗原(human leudocyte antigen,HLA-DR)在萄萄膜炎免疫反应中的作用.方法:应用免疫组织化学染色检查20只正常眼和54例葡萄糖膜炎眼球摘除眼(其中外源性33例和内源性21例)的脉络膜和视网膜组织中ICAM-1和HLA-DR的表达.结果:正常眼的脉络膜和视网膜组织没有ICAM-1的阳性染色,没有或较少有HLA-DR的表达,葡萄膜炎眼中二者有增高表达(P<0.01),而外源性和内源性葡萄膜炎眼组间表达统计学上无显著差异(P>0.05).结论:ICAM-1、HLA-DR分子能够介导白细胞和炎症部位组织细胞的识别和粘附,二者的共同表达说明它们在葡萄糖膜炎脉络膜视网膜组织的免疫性损伤中具有重要意义.%Objective :To study the effects of intercellular adhesion molecule-1 (ICAM-1) and human leukocyte antigen (HAL-DR) on the immunopathologic process of uveitis. Methods:Imn- munohistochemical techniques were applied to detect their expression in eyes of both the health (20 cases from eye bank) and patients with uveitis (54 cases with 54 eyes which included 33 ex- ogenous uveitis and 21 endogenous one). Results:Both the two ant igens were detectable in the choroidal and retinal tissues in eyes of uveitis while all the normal eyes showed negative expres- sion of ICAM-1 and negative or little expression of HLA-DR (P<0. 01). However,there was no statistically significant difference between exogenous and endogenous types (P>0. 05). Conclu- sion: Both ICAM-1 and HLA-DR may be responsible for cell recognition and binding in the in- flarnmatory tissues. The co-expression of ICAM-1 and HAL-DR showed that these two factors might play an important role in the immunologic damage of the choroid and retina in uveitis.

  5. Soluble intercellular adhesion molecule-1 for stable and acute phases of idiopathic pulmonary fibrosis.

    Science.gov (United States)

    Okuda, Ryo; Matsushima, Hidekazu; Aoshiba, Kazutetsu; Oba, Tomohiro; Kawabe, Rie; Honda, Koujiro; Amano, Masako

    2015-01-01

    The levels of soluble intercellular adhesion molecule-1 (sICAM-1) have been reported to increase in patients with idiopathic pulmonary fibrosis. However, the utility of sICAM-1 has not been reported in detail. The aim of this study was to investigate whether sICAM-1 was a useful biomarker for stable idiopathic pulmonary fibrosis (IPF) and early phase of acute exacerbation of IPF. The patients who were diagnosed with IPF between 2013 and 2015 were enrolled. The levels of sICAM-1 and other interstitial pneumonia markers were measured. In this study, 30 patients with stable IPF and 11 patients with acute exacerbation of IPF were collected. Mean sICAM-1 levels were 434 ± 139 ng/mL for the stable phase of IPF, 645 ± 247 ng/mL for early phase of acute exacerbation of IPF, 534 ± 223 ng/mL for connective tissue disease-associated interstitial pneumonia, 221 ± 42 for chronic obstructive pulmonary disease, and 150 ± 32 ng/mL in healthy volunteers. For the stable phase of IPF, sICAM-1 levels correlated with Krebs von den Lungen-6 (KL-6) (r value: 0.41; p value: 0.036). Mean sICAM-1 levels were significantly higher in patients with early phase of acute exacerbation of IPF than with stable phase of IPF (p = 0.0199). Multiple logistic analyses indicated that the predictors for early phase of acute exacerbation of IPF were only sICAM-1 and C-reactive protein (odds ratio: 1.0093; 1.6069). In patients with stable IPF, sICAM-1 levels correlated with KL-6; sICAM-1 might be a predictive indicator for prognosis. In the early phase of acute exacerbation of IPF, sICAM-1 might be more useful for diagnosis than other interstitial pneumonia markers. PMID:26543791

  6. Psychological stress increases expression of aortic plaque intercellular adhesion molecule-1 and serum inflammatory cytokines in atherosclerotic rabbit model

    Institute of Scientific and Technical Information of China (English)

    Muwei Li; Xianpei Wang; Lei Yang; Chuanyu Gao; Yexin Ma

    2008-01-01

    Plaque rupture,platelet aggregation,and thrombogenesis are the main mechanisms of acute coronary syndrome (ACS),and inflammation factors play key roles in plaque unstability.Psychological stress promotes acute inflammatory response,leading to increased circulating levels of C-reactive protein (CRP),IL-6,and serum intercellular adhesion molecule (sICAM)-1.But it is not clear that whether psychological stress has a direct effect on atherosclerotic plaque stability.The purpose of this study was to investigate effects of chronic psychological stress on inflammatory marker (ICAM-1 ) in atherosclerotic plaque,and inflammatory markers in peripheral blood.Materials and methods Sixty male rabbits were randomized into 2 groups:the control group (n =10) and the atherosclerotic group (n =50).The latter were fed on high fatty diet and were given a large dose of vitamin D3 (3 600 000IU/kg) via intraperitoneal injection.After 8 weeks,the atherosclerotic model was estaslished.Then the 50 atherosclerotic model rabbits were divided into 3 subgroups:no-stress subgroup (n = 16),physiological stress subgroup (n = 16) and psychological stress subgroup (n =18).In physiological stress subgroup and psychological stress subgroup,drinking was cut from twice a day to once a day.At the same time,psychological stress subgroup was given empty bottle stress,and this process lasted for 2 weeks.One hour after the last stress,the blood samples were collected and the serum levels of CRP,IL-6 amd ICAM-1 were tested by radioimmunoassay or enzyme linked immunosorbent assay.The aorta and heart were extracted for pathology examination,and the express of ICAM-1 was tested by immunohistochemical examination.Results (1) After effective atherosclerotic animal model construction,the expression of ICAM-1 in aorta was higher in atherosclerotic group than that in control group (P<0.01),and was notably higher in psychological stress subgroup than that in no-stress subgroup or in physiological stress subgroup (2

  7. Protective effects of green tea polyphenols against benzo[a]pyrene-induced reproductive and trans-generational toxic effects in Japanese Medaka (Oryzias latipes)

    NARCIS (Netherlands)

    Song, Chuankui; Wang, Yanli; Xiao, Zhengcao; Xiao, Bin

    2015-01-01

    In order to investigate the protective effect of green tea polyphenols (GTP) on benzo[a]pyrene (BaP)-induced reproductive and trans-generational toxicity, Japanese Medaka was injected intraperitoneally with BaP alone and co-injected with both BaP and GTP of different concentrations, respectively.

  8. The tight junction protein ZO-2 and Janus kinase 1 mediate intercellular communications in vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Tkachuk, Natalia; Tkachuk, Sergey; Patecki, Margret [Department of Nephrology, Hannover Medical School, Hannover D-30625 (Germany); Kusch, Angelika [Department of Nephrology and Intensive Care Medicine, Charite Campus Virchow-Klinikum, Berlin D-13353 (Germany); Korenbaum, Elena; Haller, Hermann [Department of Nephrology, Hannover Medical School, Hannover D-30625 (Germany); Dumler, Inna, E-mail: dumler.inna@mh-hannover.de [Department of Nephrology, Hannover Medical School, Hannover D-30625 (Germany)

    2011-07-08

    Highlights: {yields} The tight junction protein ZO-2 associates with Jak1 in vascular smooth muscle cells via ZO-2 N-terminal fragment. {yields} Jak1 mediates ZO-2 tyrosine phosphorylation and ZO-2 localization to the sites of homotypic intercellular contacts. {yields} The urokinase receptor uPAR regulates ZO-2/Jak1 functional association. {yields} The ZO-2/Jak1/uPAR signaling complex is required for vascular smooth muscle cells functional network formation. -- Abstract: Recent evidence points to a multifunctional role of ZO-2, the tight junction protein of the MAGUK (membrane-associated guanylate kinase-like) family. Though ZO-2 has been found in cell types lacking tight junction structures, such as vascular smooth muscle cells (VSMC), little is known about ZO-2 function in these cells. We provide evidence that ZO-2 mediates specific homotypic cell-to-cell contacts between VSMC. Using mass spectrometry we found that ZO-2 is associated with the non-receptor tyrosine kinase Jak1. By generating specific ZO-2 constructs we further found that the N-terminal fragment of ZO-2 molecule is responsible for this interaction. Adenovirus-based expression of Jak1 inactive mutant demonstrated that Jak1 mediates ZO-2 tyrosine phosphorylation. By means of RNA silencing, expression of Jak1 mutant form and fluorescently labeled ZO-2 fusion protein we further specified that active Jak1, but not Jak1 inactive mutant, mediates ZO-2 localization to the sites of intercellular contacts. We identified the urokinase receptor uPAR as a pre-requisite for these cellular events. Functional requirement of the revealed signaling complex for VSMC network formation was confirmed in experiments using Matrigel and in contraction assay. Our findings imply involvement of the ZO-2 tight junction independent signaling complex containing Jak1 and uPAR in VSMC intercellular communications. This mechanism may contribute to vascular remodeling in occlusive cardiovascular diseases and in arteriogenesis.

  9. The NLRP3 Inflammasome Is a Pathogen Sensor for Invasive Entamoeba histolytica via Activation of α5β1 Integrin at the Macrophage-Amebae Intercellular Junction.

    Directory of Open Access Journals (Sweden)

    Leanne Mortimer

    2015-05-01

    Full Text Available Entamoeba histolytica (Eh is an extracellular protozoan parasite of humans that invades the colon to cause life-threatening intestinal and extra-intestinal amebiasis. Colonized Eh is asymptomatic, however, when trophozoites adhere to host cells there is a considerable inflammatory response that is critical in the pathogenesis of amebiasis. The host and/or parasite factors that trigger the inflammatory response to invading Eh are not well understood. We recently identified that Eh adherence to macrophages induces inflammasome activation and in the present study we sought to determine the molecular events upon contact that coordinates this response. Here we report that Eh contact-dependent activation of α5β1 integrin is critical for activation of the NLRP3 inflammasome. Eh-macrophage contact triggered recruitment of α5β1 integrin and NLRP3 into the intercellular junction, where α5β1 integrin underwent activation by an integrin-binding cysteine protease on the parasite surface, termed EhCP5. As a result of its activation, α5β1 integrin induced ATP release into the extracellular space through opening of pannexin-1 channels that signalled through P2X7 receptors to deliver a critical co-stimulatory signal that activated the NLRP3 inflammasome. Both the cysteine protease activity and integrin-binding domain of EhCP5 were required to trigger α5β1 integrin that led to ATP release and NLRP3 inflammasome activation. These findings reveal engagement of α5β1 integrin across the parasite-host junction is a key regulatory step that initiates robust inflammatory responses to Eh. We propose that α5β1 integrin distinguishes Eh direct contact and functions with NLRP3 as pathogenicity sensor for invasive Eh infection.

  10. The vascular plant-pathogenic bacterium Ralstonia solanacearum produces biofilms required for its virulence on the surfaces of tomato cells adjacent to intercellular spaces.

    Science.gov (United States)

    Mori, Yuka; Inoue, Kanako; Ikeda, Kenichi; Nakayashiki, Hitoshi; Higashimoto, Chikaki; Ohnishi, Kouhei; Kiba, Akinori; Hikichi, Yasufumi

    2016-08-01

    The mechanism of colonization of intercellular spaces by the soil-borne and vascular plant-pathogenic bacterium Ralstonia solanacearum strain OE1-1 after invasion into host plants remains unclear. To analyse the behaviour of OE1-1 cells in intercellular spaces, tomato leaves with the lower epidermis layers excised after infiltration with OE1-1 were observed under a scanning electron microscope. OE1-1 cells formed microcolonies on the surfaces of tomato cells adjacent to intercellular spaces, and then aggregated surrounded by an extracellular matrix, forming mature biofilm structures. Furthermore, OE1-1 cells produced mushroom-type biofilms when incubated in fluids of apoplasts including intercellular spaces, but not xylem fluids from tomato plants. This is the first report of biofilm formation by R. solanacearum on host plant cells after invasion into intercellular spaces and mushroom-type biofilms produced by R. solanacearum in vitro. Sugar application led to enhanced biofilm formation by OE1-1. Mutation of lecM encoding a lectin, RS-IIL, which reportedly exhibits affinity for these sugars, led to a significant decrease in biofilm formation. Colonization in intercellular spaces was significantly decreased in the lecM mutant, leading to a loss of virulence on tomato plants. Complementation of the lecM mutant with native lecM resulted in the recovery of mushroom-type biofilms and virulence on tomato plants. Together, our findings indicate that OE1-1 produces mature biofilms on the surfaces of tomato cells after invasion into intercellular spaces. RS-IIL may contribute to biofilm formation by OE1-1, which is required for OE1-1 virulence. PMID:26609568

  11. Soluble Inter-Cellular Adhesion Molecule-1 in Urban Asian North Indians: Relationships with Anthropometric and Metabolic Covariates

    Directory of Open Access Journals (Sweden)

    Astha Sethi

    2002-01-01

    Full Text Available Background: High prevalence of diabetes, obesity, and dyslipidemias in people belonging to poor socio-economic strata in urban slums of northern India has been recorded recently. To assess whether this population has high levels of soluble intercellular adhesion molecule-1 (sICAM-1, a cytokine involved in the pathogenesis of atherosclerosis, we investigated subjects belonging to poor socio-economic strata in urban slums and compared them to healthy control subjects from non-slum urban areas of New Delhi.

  12. Induction and recovery of morphofunctional changes in the intestine of juvenile carnivorous fish (Epinephelus coioides) upon exposure to foodborne benzo[a]pyrene

    Energy Technology Data Exchange (ETDEWEB)

    Yuen, Bonny B.H. [Centre for Coastal Pollution and Conservation, Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong (China); Nicholas School of the Environment, Duke University, Durham, NC (United States); Wong, Chris K.C. [Department of Biology, Baptist University of Hong Kong, Waterloo Road, Kowloon, Hong Kong (China); Woo, N.Y.S. [Department of Biology, Chinese University of Hong Kong, New Territory, Hong Kong (China); Au, Doris W.T. [Centre for Coastal Pollution and Conservation, Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong (China)]. E-mail: bhdwtau@cityu.edu.hk

    2007-05-15

    The sublethal toxicity of dietary benzo[a]pyrene, B[a]P, on fish growth and intestinal morphofunctional changes [as measured by epithelial turnover, cell proliferation, hyperplasia, de novo crypt formation and protein absorption efficiency (i.e. expression of proton/peptide co-transporter, PepT-1, on the mucosal brush border)] were studied for the carnivorous orange-spotted grouper (Epinephelus coioides). Juvenile fish were force-fed daily with pellets containing environmentally realistic concentrations of B[a]P (dissolved in corn oil) at 0.25 {mu}g/g body weight (low-dose) and 12.5 {mu}g/g body weight (high-dose) for 4 weeks, followed by a control diet for a further 4 weeks to assess recovery. Although growth inhibition was observed in fish treated with high-dose B[a]P during the exposure period, no mortality was observed throughout the 8-week experiment. Significant hyperplasia of basal enterocytes of mucosal folds was detected shortly after 3-day exposure to the high-dose B[a]P. Moreover, a faster epithelial turnover was measured in the high-dose B[a]P exposed fish at exposure week 1, which was followed by an increase of basal cell proliferation and a reduction of PepT-1 expression at exposure week 2. The formation of de novo crypts, resemblance to the cancer predisposition syndrome 'juvenile polyposis', was significantly higher in the intestine of high-dose treated fish as compared to the control at exposure week 2 and onwards. Abnormal cytoplasmic extrusions were frequently observed in mucosal folds of high-dose fish at exposure week 4. In the low-dose treatment group, only the expression of PepT-1 was significantly reduced at exposure week 2 and an early adaptive response was observed at exposure week 4. Despite all these intestinal disturbances were reversible in fish upon the abatement to dietary B[a]P (within 1-4 weeks), environmental realistic levels of foodborne B[a]P could induce sublethal toxicity to E. coioides, and probably impose potential

  13. Effects of light on the cytotoxicity and genotoxicity of benzo(a)pyrene and an oil refinery effluent in the newt

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, M.; l`Haridon, J. [Universite Paul-Sabatier, Toulouse (France)

    1994-12-31

    The genotoxicity and/or toxicity of benzo(a)pyrene (BaP) were evaluated under different lighting conditions in larvae and embryos of the newt Pleurodeles waltl. Visible light alone, UVA alone, or BaP alone had no toxic effects on the larvae. Conversely, toxic effects were observed in animals exposed to BaP + daylight, or BaP + UVA. The genotoxicity of BaP (50 ppb) was halved by its previous exposure to UVA, and was abolished at the lowest concentration (12.5 ppb). In other experiments, the larvae were exposed alternatively to BaP or Irr BaP (18 hours in dark) and UVA (6 hr in water), every day for 8 days. All animals that had accumulated non-irradiated BaP (50 ppb) showed signs of severe toxicity, and 90% died before the end of the test. On the other hand, irradiated BaP (50 ppb) was a 4-fold less toxic and half as genotoxic as non-irradiated BaP. In addition, exposure of the animals to UVA alone for 4 days prior to treatment with BaP did not affect the genotoxicity or toxicity of this hydrocarbon. In the dark, the embryotoxicity of BaP was markedly attenuated by the presence of the jelly coats. Although UVA alone did not affect growth of the embryos, the toxicity of BaP was enhanced by the combined action of the two agents together or in succession (BaP + UVA or BaP then UVA). Larvae were treated with an oil refinery effluent (EF). At 125 ml/l, EF was not found to be genotoxic in the dark. However, in animals exposed to both EF and UVA, there was a progressive increase in level of micronucleated erythrocytes with increasing duration of daily exposure to UVA. Moreover, the genotoxic potential of irradiated EF + UVA was systematically below that of non-irradiated EF + UVA for all durations of exposure to ultraviolet light. Irradiation of this type of effluent might help reduce its harmful effects on aquatic species. Our results also suggest that metabolic activation is not necessary for hydrocarbons to induce toxic effects. 51 refs., 5 tabs., 3 figs.

  14. Metabolism of benzo(a)pyrene and identification of the major benzo(a)pyrene-DNA adducts in cultured human colon

    DEFF Research Database (Denmark)

    1978-01-01

    was formed between benzo(a)pyrene diol-epoxide II and the 2-amino group of guanine. The major metabolites of benzo(a)pyrene extracted with ethyl acetate/acetone from the tissue culture media were (7,10/8,9)-tetrahydroxy-7,10,8,9-tetrahydrobenzo(a)pyrene, trans-7,8-dihydroxy-7,8-dihydrobenzo......% of the metabolites remained in the water phase after extraction with ethy(acetate/acetone. frans-7,8-Dihydroxy-7,8-dihydrobenzo(a)pyrene and quiñoneswere the major metabolites released when the water-soluble metabolites were treated with /3-glucuronidase and arylsulfatase. The binding levels of benzo...

  15. A study of soluble intercellular adhesion molecule-1 in sera of patients with thyroid diseases

    International Nuclear Information System (INIS)

    Objective: Markedly elevated serum soluble intercellular adhesion molecule 1 (sICAM-1) level has recently been reported in patients with autoimmune thyroid disease (AITD). The aim of this study was to investigate the clinical significance of sICAM-1 serum level in patients with different thyroid diseases. Methods: A total of 616 patients were recruited, consisting of 557 Graves' disease (CD), 33 untreated Hashimoto's thyroiditis (HT), 17 untreated simple goiter (SG) and 9 nontoxic nodular goiter (NTNG). Control was a group of 273 healthy individuals with no prior history of thyroid disease. Their serum sICAM-1 levels were measured by 125I-sICAM-1 radioimmunoassay. If sICAM-1 levels of every group fit normal distribution, statistical difference was calculated by ANOVA or t-test; if not, then rank sum test (Kruskal-Wallis or Mann-Whitney) was used. Results: There was no statistically significant difference among the SG [(173.82 ± 59.50) μg/L], NTNG [(159.31 ± 28.73) μg/L] and control [(149.89 ± 39.45) μg/L] groups; whereas the levels in both untreated GD [(255.04 ± 82.40) μg/L] and HT[(227.22 ± 77.08) μg/L] groups were elevated and statistically significant by comparison with the control group (Z=-9.401, -5.902, respectively; both with P 2=88.257, P<0.01). In stable euthyroid patients receiving ATD, a steady trend of gradual decline in sICAM-1 levels was found. When ATD treatment lasted ≥19 months, the sICAM-1 levels in GD patients with and without ophthalmopathy [(211.58 ± 53.58) μg/L and (189.50 ± 39.99) μg/L, respectively] were significantly decreased when compared with the corresponding pair of new-onset groups [(287.36 ± 79.20) μg/L and (244.75 ± 81.58) μg/L, F=9.986, 3.398, respectively; all P<0.05] but remained persistently elevated over the control group even after stopping ATD treatment (Z=-3.813, P<0.05). Conclusions: The sICAM-1 assay is of great importance in the diagnosis of AITD and detection of the associated abnormal immune status

  16. Clinical evaluation of serum concentrations of intercellular adhesion molecule-1 in patients with colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Xu Kang; Fang Wang; Jin-Dong Xie; Jun Cao; Pei-Zhong Xian

    2005-01-01

    AIM: To investigate the correlation between the serum soluble intercellular adhesion molecule-1 (sICAM-1) and the clinicopathologic features and to evaluate the possible prognostic significance of sICAM-1 concentration in colorectal cancer.METHODS: A total of 56 patients (mean age 57.3 years)having transitional cell carcinoma of the colorectal and 25 control patients (mean age 42.6 years) were enrolled in the study. The serum samples of the patients were obtained on the day before surgery. Sera were obtained by centrifugation, and stored at -80 ℃ until assay. Serumconcentrations of ICAM-1 were measured with enzymelinked immunoassay. Differences between the two groups were analyzed by Student's t-test.RESULTS: No significant increase of serum sICAM-1 could be demonstrated in the Dukes A1 patients (352.63±61.82μg/L) compared to the control group (345.72±49.81 μg/L,P>0.05), Dukes A1 patients (352.63±61.82 μg/L)compared to Dukes A2,3 patients (491.17±86.36 μg/L,P<0.05). Furthermore, the patients with Dukes B had significantly higher serum concentrations of sICAM-1than those of the control group (496.82±93.04 μg/L vs 345.72±49.81 μg/L, P<0.01). Compared with Dukes A2,3,B colorectal cancer patients, patients with more advanced clinical stage (Dukes C and D) had higher levels of sICAM-1 (743.68±113.74 μg/L vs491.17±86.36 μg/L and 496.82±93.04 μg/L, P<0.001). The difference was statistically significant in sICAM-1 levels between patients with positive lymph node status and those without lymph node involvement (756.25±125.57 μg/L vs445.62±69.18 μg/L, P<0.001).Patients with poorly differentiated colorectal cancer had a higher level of sICAM-1 than those with differentiated and highly differentiated cancer (736.49±121.97 μg/Lvs 410.23±67.47 μg/L, P<0.001).CONCLUSION: In this study, serum ICAM-1 levels were found to be related to tumor presence, clinical stages,and grade. Increased ICAM-1 in patients with colorectal cancer which should

  17. Enhanced oxidation of benzo[a]pyrene by crude enzyme extracts produced during interspecific fungal interaction of Trametes versicolor and Phanerochaete chrysosporium

    Institute of Scientific and Technical Information of China (English)

    Linbo Qian; Baoliang Chen

    2012-01-01

    The effects of interspecific fungal interactions between Trametes versicolor and Phanerochaete chrysosporium on laccase activity and enzymatic oxidation of polycyclic aromatic hydrocarbons (PAHs) were investigated.A deadlock between the two mycelia rather than replacement of one fungus by another was observed on an agar medium.The laccase activity in crude enzyme extracts from interaction zones reached a maximum after a 5-day incubation,which was significantly higher than that from regions of T.versicolor or P.chrysosporium alone.The enhanced induction of laccase activity lasted longer in half nutrition than in normal nutrition.A higher potential to oxidize benzo[a]pyrene by a crude enzyme preparation extracted from the interaction zones was demonstrated.After a 48 hr incubation period,the oxidation of benzo[a]pyrene by crude enzyme extracts from interaction zones reached 26.2%,while only 9.5% of benzo[a]pyrene was oxidized by crude extracts from T.versicolor.The oxidation was promoted by the co-oxidant 2,2'-azinobis-3-ethylbenzthiazoline-6-sulphonate diammonium salt (ABTS).These findings indicate that the application of co-culturing of white-rot fungi in bioremediation is a potential ameliorating technique for the restoration of PAH-contaminated soil.

  18. Expression and intercellular trafficking of the VP22 protein of CVI988/Rispens vaccine strain of Marek's disease virus

    Institute of Scientific and Technical Information of China (English)

    CHEN HongJun; SONG CuiPing; QIN AiJian; ZHANG ChenFei

    2007-01-01

    The viral protein 22 (VP22) in the tegument of Marek's disease virus serotype 1 (MDV-1) plays an important role in cell-to-cell spread and viral propagation. Antiserum against the carboxyl terminus of VP22 was prepared by immunizing mice with recombinant VP22 expressed in E. coli, and used to investigate its expression in chicken embryo fibroblast (CEF) cells infected with different MDV-1 strains. At an infection dose of PFU=50, intercellular trafficking of the VP22 into the nuclei of the surrounding receipt cells was detected as early as 3 hours post infection. By 6 hours after infection (before viral plague formation), the protein was detected in the whole nuclei of the recipient cells with no difference among MDV-1 strains CVI988/Rispens, GA and RB1B. Intra-nuclear accumulation of the VP22 protein was further increased when the viral plagues started to form. These results indicate that, albeit the existence of the 201TKSERT206 deletion, the VP22 of the CVI988/Rispens vaccine strain has also intercellular-trafficking function, which might serve as a potential alternative delivering protein instead of virulent strains VP22.

  19. Antimutagenic activity of cashew apple (Anacardium occidentale Sapindales, Anacardiaceae fresh juice and processed juice (cajuína against methyl methanesulfonate, 4-nitroquinoline N-oxide and benzo[a]pyrene

    Directory of Open Access Journals (Sweden)

    Ana Amelia Melo-Cavalcante

    2008-01-01

    Full Text Available Cashew apple juice (CAJ, produced from the native Brazilian cashew tree (Anacardium occidentale, and has been reported to have antibacterial, antifungal, antitumor, antioxidant and antimutagenic properties. Both the fresh unprocessed juice and the processed juice (cajuína in Portuguese has been shown to consist of a complex mixture containing high concentrations of anacardic and ascorbic acids plus several carotenoids, phenolic compounds and metals. We assessed both types of juice for their antimutagenic properties against the direct mutagens methyl methanesulfonate (MMS and 4-nitroquinoline-N-oxide (4-NQO and the indirect mutagen benzo[a]pyrene (BaP using pre-treatment, co-treatment and post-treatment assays with Salmonella typhimurium strains TA100, TA102, and TA97a. In pre-treatment experiments with strains TA100 and TA102 the fresh juice showed high antimutagenic activity against MMS but, conversely, co-treatment with both juices enhanced MMS mutagenicity and there was an indication of toxicity in the post-treatment regime. In pre-, co-, and post-treatments with TA97a as test strain, antimutagenic effects were also observed against 4-NQO and BaP. These results suggest that both fresh and processed CAJ can protect the cells against mutagenesis induced by direct and indirect mutagens.

  20. Protective effects of Brussels sprouts towards B[a]P-induced DNA damage: a model study with the single-cell gel electrophpresis (SCGE)/Hep G2 assay

    NARCIS (Netherlands)

    Laky, B.; Knasmuller, S.; Gminski, R.; Mersch-Sundermann, V.; Scharf, G.; Verkerk, R.; Freywald, C.; Uhl, M.; Kassie, F.

    2002-01-01

    The aim of this study was to investigate the chemoprotective effects of Brussels sprouts juice towards benzo[a]pyrene (B(a)P)-induced DNA damage in the single-cell gel electrophoresis (SCGE)/Hep G2 test system. This assay combines the advantages of the SCGE assay with that of the use of human-derive

  1. Effect of Soil Aging on the Phytoremediation Potential of Zea mays in Chromium and Benzo[a]Pyrene Contaminated Soils.

    Science.gov (United States)

    Chigbo, Chibuike

    2015-06-01

    This study compared the phytoremediation potential of Zea mays in soil either aged or freshly amended with chromium (Cr) and benzo[a]pyrene (B[a]P). Z. mays showed increased shoot biomass in aged soils than in freshly spiked soils. The shoot biomass in contaminated soils increased by over 50% in aged soil when compared to freshly amended soils, and over 29% more Cr was accumulated in the shoot of Z. mays in aged soil than in freshly amended soil. Planting Z. mays in aged soil helped in the dissipation of more than 31% B[a]P than in freshly spiked soil, but in the absence of plants, there seemed to be no difference between the dissipation rates of B[a]P in freshly and aged co-contaminated soil. Z. mays seemed to enhance the simultaneous removal of Cr and B[a]P in aged soil than in freshly spiked soil and hence can be a good plant choice for phytoremediation of co-contaminated soils.

  2. Paternal Benzo[a]pyrene Exposure Modulates MicroRNA Expression Patterns in the Developing Mouse Embryo

    Directory of Open Access Journals (Sweden)

    Asgeir Brevik

    2012-01-01

    Full Text Available Little attention has been given to how microRNA expression is affected by environmental contaminants exposure. We investigate the effects of paternal exposure to benzo[a]pyrene (B[a]P on miRNA expression in the developing mouse embryo. Male mice were exposed to B[a]P (150 mg/kg i.p., and their sperm was used four days later in in-vitro fertilization experiments. Twenty embryos each from 2-, 8-cell and the blastocyst stage were used for genome-wide miRNA expression profiling. Paternal exposure to B[a]P affected the expression of several miRNAs, and the target genes for some of the dysregulated miRNAs were enriched in many different pathways that are likely to be relevant for the developing mouse embryo. By linking the miRNA target genes to publicly available databases, we identified some miRNA target genes that may serve as global markers of B[a]P-mediated genotoxic stress. The dysregulated miRNAs may provide valuable knowledge about potential transgenerational effects of sublethal exposure to chemicals.

  3. Can we use modelling methodologies to assess airborne benzo[a]pyrene from biomonitors? A comprehensive evaluation approach

    Directory of Open Access Journals (Sweden)

    N. Ratola

    2015-09-01

    Full Text Available Biomonitoring data available on levels of atmospheric polycyclic aromatic hydrocarbons (PAHs in pine needles from the Iberian Peninsula was used to estimate air concentrations of benzo[a]pyrene (BaP and, at the same time, fuelled the comparison with chemistry transport model representations. Simulations with the modelling system WRF + CHIMERE were validated against data from the European Monitoring and Evaluation Programme (EMEP air sampling network and using modelled atmospheric concentrations as a consistent reference in order to compare the performance of vegetation-to-air estimating methods. A spatial and temporal resolution of 9 km and 1 h was implemented. The field-based database relied on a pine needles sampling scheme comprising 33 sites in Portugal and 37 sites in Spain complemented with the BaP measurements available from the EMEP sites. The ability of pine needles to act as biomonitoring markers for the atmospheric concentrations of BaP was estimated converting the levels obtained in pine needles into air concentrations by six different approaches, one of them presenting realistic concentrations when compared to the modelled atmospheric values. The justification for this study is the gaps still existing in the knowledge of the life cycles of semi-volatile organic compounds (SVOCs, particularly the partition processes between air and vegetation. The strategy followed in this work allows the definition of the transport patterns (e.g. dispersion established by the model for atmospheric concentrations and the estimated values in vegetation.

  4. Effects of benzo(a)pyrene on the skeletal development of Sebastiscus marmoratus embryos and the molecular mechanism involved

    Energy Technology Data Exchange (ETDEWEB)

    He Chengyong [Key Laboratory of Ministry of Education for Subtropical Wetland Ecosystem Research, School of Life Sciences, Xiamen University, Xiamen (China); Zuo Zhenghong [Key Laboratory of Ministry of Education for Subtropical Wetland Ecosystem Research, School of Life Sciences, Xiamen University, Xiamen (China); State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen (China); Shi Xiao; Li Ruixia; Chen Donglei; Huang Xin; Chen Yixin [Key Laboratory of Ministry of Education for Subtropical Wetland Ecosystem Research, School of Life Sciences, Xiamen University, Xiamen (China); Wang Chonggang, E-mail: cgwang@xmu.edu.cn [Key Laboratory of Ministry of Education for Subtropical Wetland Ecosystem Research, School of Life Sciences, Xiamen University, Xiamen (China); State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen (China)

    2011-01-25

    Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental contaminants, which have been known to be carcinogenic and teratogenic. However, the skeletal development toxicity of PAHs and the mechanism involved remain unclear. In fishes, the neurocranial and craniofacial skeleton develop as cartilage. The signaling molecules of hedgehog (Hh) family play crucial roles in regulating skeletal development. In the present study, rockfish (Sebastiscus marmoratus) embryos were exposed to benzo(a)pyrene (BaP) for 7 days at environmental levels (0.05, 0.5 and 5 nmol/L) which resulted in craniofacial skeleton deformities. BaP exposure reduced the cell proliferation activity in the craniofacial skeleton as detected by quantitative PCR and in situ hybridization. The expression of Sonic hedgehog (Shh), rather than Indian hedgehog (Ihh), was down-regulated in the craniofacial skeleton in the 0.5 and 5 nmol/L groups. Consistent with the Shh results, the expression of Ptch1 and Gli2 was decreased by BaP exposure and BMP4 was presented on changes in the 0.5 and 5 nmol/L groups. These results suggested that BaP could impair the expression and function of Shh signaling pathway, perturbing the proliferation of chondrocytes and so disturbing craniofacial skeletal development.

  5. Metabolism and macromolecular binding of benzo(a)pyrene and its noncarcinogenic isomer benzo(e)pyrene in cell culture

    Energy Technology Data Exchange (ETDEWEB)

    Selkirk, J.K.; MacLeod, M.C.

    1978-01-01

    The carcinogenicity of the polycyclic aromatic hydrocarbon benzo(a)pyrene (B(a)P) is thought to result from the metabolic formation of a highly reactive intermediate, 7,8-dihydrodiol-9,10-oxy-B(a)P which subsequently interacts with cellular macromolecules to produce neoplasia. Evidence has been presented implicating similar bay-region diol-epoxides as the ultimate carcinogenic forms of benz(a)anthracene, 7-methyl-benz(a)anthracene, dibenz(a,h)anthracene, and chrysene. Benzo(e)pyrene (B(e)P), on the other hand, is relatively inert when tested for carcinogenicity on mouse skin and rat trachea and when tested for mutagenicity in a mammalian system. This B(e)P molecule contains two (equivalent) bay regions and quantum mechanical model calculations suggest that 9,10-dihydrodiol-11,12-oxy-B(e)P can easily form a reactive bay-region-adjacent carbonium ion. In order to explain the noncarcinogenicity of B(e)P in the context of the bay region theory, we have studied the metabolism of B(e)P by rat liver microsomes and by cultured hamster embryo fibroblasts. In both systems, the major metabolic pathways involve the K-region of B(e)P, with little or no attack on the isolated benzo ring. These results suggest that the lack of carcinogenicity of B(e)P may reflect its preferred mode of interaction with the cellular metabolic machinery.

  6. Influence of diet and ration level on benzo[a]pyrene metabolism and excretion in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Kennedy, C J; Higgs, Dave; Tierney, Keith

    2004-10-01

    Juvenile rainbow trout (Oncorhynchus mykiss) were fasted or fed one of three isoenergetic diets varying in protein and lipid content at full satiation levels or half rations for up to 9 weeks. At 3, 6, and 9 weeks, fish in each treatment group were dosed intraperitoneally with 10 mg tritiated benzo[a]pyrene [3H]-B[a]P/kg (B[a]P) to examine the effects of diet composition and energy intake on xenobiotic biotransformation and excretion. The percent dose eliminated during the experiment did not differ among fish receiving the different diet compositions or rations (range 73% to 84%). However, it was significantly decreased (to 53%) in the group that was fasted for 9 weeks. Examination of fish fasted for 6 and 9 weeks showed a significant increase in the proportion of phase I metabolites and a concomitant decrease in the proportion of phase II metabolites found in bile compared with all other groups. Also, fish that were fasted for 9 weeks produced proportionately less 9,10-dihydroxy-benzo[a]pyrene-trans-9,10-diol, more 3-hydroxybenzo[a]pyrene and 9-hydroxybenzo[a]pyrene, and more glucuronic acid conjugates compared with all other groups. Thus, dietary protein and lipid concentration did not appear to affect either the rate of B[a]P metabolism or its excretion; however, prolonged fasting resulted in a shift in metabolite profiles and decreased excretion.

  7. Inhibitory effects of isoproterenol on PAF-induced endothelial cell permeability and morphological changes

    Institute of Scientific and Technical Information of China (English)

    丁自强; 李少华; 吴中立

    1996-01-01

    Using a model to study vascular permeability under hydrostatically perfused bovine pulmonary artery endothelial cell (EC) monolayers and a software to automatically analyse cell morphological parameters in a computer image workstation, the effects of isoproterenol (IPN) on platelet-activating factor (PAF)-induced changes in EC monolayer permeability and cell morphological parameters were studied. Albumin has the fortifying effect on endothelial barrier function. After treatment of EC monolayer with 10-8mol/L PAF, trans-monolayer permeability increased, cell surface area decreased, and intercellular space enlarged. As pretreatment with 10-4mol/L IPN, PAF-induced EC permeability increment and morphological changes were blocked. The results suggest that EC contraction and intercellular gap expansion are important mechanisms for PAF-induced high vascular permeability. IPN inhibits the effects of PAF via stabilization of EC morphology and prevention of intercellular gap formation.

  8. The Influence of Ionizing Radiation on Exosome Composition, Secretion and Intercellular Communication

    Science.gov (United States)

    Jelonek, Karol; Widlak, Piotr; Pietrowska, Monika

    2016-01-01

    A large variety of vesicles is actively secreted into the extracellular space by most type of cells. The smallest nanoparticles (30-120 nm), called exosomes, are known to transport their cargo (nucleic acids, proteins and lipids) between diverse locations in the body. Specific content of exosomes and their influence on recipient cells depends primarily on the type of the secretory (donor) cell, yet several studies highlight the importance of environmental stress on which the donor cells are exposed. Ionizing radiation, which induces damage to DNA and other structures of a target cell, is one of well-recognized stress conditions influencing behavior of affected cells. A few recent studies have evidenced radiation-induced changes in composition of exosomes released from irradiated cells and their involvement in radiation-related communication between cells. Inducible pathways of exosome secretion activated in irradiated cells are regulated by TSAP6 protein (the transmembrane protein tumor suppressor-activated pathway 6), which is transcriptionally regulated by p53, hence cellular status of this major DNA damage response factor affects composition and secretion rate of exosomes released from target cells. Moreover, exosomes released from irradiated cells have been shown to mediate the radiation-induced bystander effect. Understanding radiation-related mechanisms involved in exosome formation and “makeup” of their cargo would shed light on the role of exosomes in systemic response of cells, tissues and organisms to ionizing radiation which may open new perspectives in translational medicine and anticancer-treatment. PMID:27117741

  9. Laminin-111 stimulates proliferation of mouse embryonic stem cells through a reduction of gap junctional intercellular communication via RhoA-mediated Cx43 phosphorylation and dissociation of Cx43/ZO-1/drebrin complex.

    Science.gov (United States)

    Suh, Han Na; Kim, Mi Ok; Han, Ho Jae

    2012-07-20

    Gap junctions within extracellular matrix (ECM)-defined boundaries ensure synchronous activity between cells destined to become functional mediators that regulate cell behavior. However, the role of ECM in connexin (Cx) function in mouse embryonic stem cells (mESCs) has not been elucidated. Therefore, we examined the role of laminin-111 in the control of Cx43 functions and related signal pathways in mESCs. ECM components (laminin-111, fibronectin, and collagen I) increased Cx43 phosphorylation and decreased Lucifer yellow (Ly) diffusion. In addition, laminin-111 increased the proliferation index through reduction of gap junctional intercellular communication (GJIC), which was confirmed by 18α-glycyrrhetinic acid (18α-GA). Laminin-111 increased phosphorylation of focal adhesion kinase (FAK)/Src and protein kinase C (PKC), which were inhibited by integrin β1 antibody (Ab) and laminin receptor-1 (LR-1) Ab, respectively. In addition, inhibition of both FAK/Src and PKC blocked Cx43 phosphorylation. Laminin-111 increased the Ras homolog gene family, member A (RhoA) activation, which was blocked by FAK/Src and PKC inhibitors, suggesting the existence of parallel pathways that merge at RhoA. Inhibition of RhoA reversed the laminin-111-induced increase of Cx43 phosphorylation and reduction of GJIC. Laminin-111 also stimulated the dissociation of Cx43/ZO-1 complex followed by disruption of Cx43/drebrin and Cx43/F-actin complexes, which were reversed by C3 (RhoA inhibitor). ZO-1 small interfering (si) RNA significantly decreased Ly diffusion. Moreover, laminin-111 decreased Cx43 labeling at the intercellular junction, whereas pretreatment with degradation inhibitors (lysosomal protease inhibitor, chloroquine; proteasome inhibitor, lactacystin) increased Cx43 expression, reversely. In conclusion, laminin-111 stimulated mESC proliferation through a reduction of GJIC via RhoA-mediated Cx43 phosphorylation and Cx43/ZO-1/drebrin complex instability-mediated Cx43 degradation

  10. Nitric oxide pretreatment enhances atheroma component highlighting in vivo with intercellular adhesion molecule-1-targeted echogenic liposomes.

    Science.gov (United States)

    Kee, Patrick H; Kim, Hyunggun; Huang, Shaoling; Laing, Susan T; Moody, Melanie R; Vela, Deborah; Klegerman, Melvin E; McPherson, David D

    2014-06-01

    We present an ultrasound technique for the detection of inflammatory changes in developing atheromas. We used contrast-enhanced ultrasound imaging with (i) microbubbles targeted to intercellular adhesion molecule-1 (ICAM-1), a molecule of adhesion involved in inflammatory processes in lesions of atheromas in New Zealand White rabbits, and (ii) pretreatment with nitric oxide-loaded microbubbles and ultrasound activation at the site of the endothelium to enhance the permeability of the arterial wall and the penetration of ICAM-1-targeted microbubbles. This procedure increases acoustic enhancement 1.2-fold. Pretreatment with nitric oxide-loaded echogenic liposomes and ultrasound activation can potentially facilitate the subsequent penetration of targeted echogenic liposomes into the arterial wall, thus allowing improved detection of inflammatory changes in developing atheromas.

  11. Modeling Intercellular Communication as a Survival Strategy of Cancer Cells: An In Silico Approach on a Flexible Bioinformatics Framework

    Science.gov (United States)

    Cárdenas-García, Maura; González-Pérez, Pedro P.; Montagna, Sara; Cortés, Oscar Sánchez; Caballero, Elena Hernández

    2016-01-01

    Intercellular communication is very important for cell development and allows a group of cells to survive as a population. Cancer cells have a similar behavior, presenting the same mechanisms and characteristics of tissue formation. In this article, we model and simulate the formation of different communication channels that allow an interaction between two cells. This is a first step in order to simulate in the future processes that occur in healthy tissue when normal cells surround a cancer cell and to interrupt the communication, thus preventing the spread of malignancy into these cells. The purpose of this study is to propose key molecules, which can be targeted to allow us to break the communication between cancer cells and surrounding normal cells. The simulation is carried out using a flexible bioinformatics platform that we developed, which is itself based on the metaphor chemistry-based model. PMID:26997867

  12. Glyceraldehyde 3-phosphate dehydrogenase augments the intercellular transmission and toxicity of polyglutamine aggregates in a cell model of Huntington disease.

    Science.gov (United States)

    Mikhaylova, Elena R; Lazarev, Vladimir F; Nikotina, Alina D; Margulis, Boris A; Guzhova, Irina V

    2016-03-01

    The common feature of Huntington disease is the accumulation of oligomers or aggregates of mutant huntingtin protein (mHTT), which causes the death of a subset of striatal neuronal populations. The cytotoxic species can leave neurons and migrate to other groups of cells penetrating and damaging them in a prion-like manner. We hypothesized that the glycolytic enzyme glyceraldehyde 3-phosphate dehydrogenase (GAPDH), previously shown to elevate the aggregation of mHTT, is associated with an increased efficiency of intercellular propagation of mHTT. GAPDH, on its own or together with polyglutamine species, was shown to be released into the extracellular milieu mainly from dying cells as assessed by a novel enzyme immunoassay, western blotting, and ultrafiltration. The conditioned medium of cells with growing GAPDH-polyQ aggregates was toxic to naïve cells, whereas depletion of the aggregates from the medium lowered this cytotoxicity. The GAPDH component of the aggregates was found to increase their toxicity by two-fold in comparison with polyQ alone. Furthermore, GAPDH-polyQ complexes were shown to penetrate acceptor cells and to increase the capacity of polyQ to prionize its intracellular homolog containing a repeat of 25 glutamine residues. Finally, inhibitors of intracellular transport showed that polyQ-GAPDH complexes, as well as GAPDH itself, penetrated cells using clathrin-mediated endocytosis. This suggested a pivotal role of the enzyme in the intercellular transmission of Huntington disease pathogenicity. In conclusion, GAPDH occurring in complexes with polyglutamine strengthens the prion-like activity and toxicity of the migrating aggregates. Aggregating polygluatmine tracts were shown to release from the cells over-expressing mutant huntingtin in a complex with glyceraldehyde 3-phosphate dehydrogenase (GAPDH). The enzyme enhances the intracellular transport of aggregates to healthy cells, prionization of normal cellular proteins and finally cell death, thus

  13. Intercellular heterogeneity of expression of the MGMT DNA repair gene in pediatric medulloblastoma1

    OpenAIRE

    Rood, Brian R.; Zhang, Huizhen; Cogen, Philip H.

    2004-01-01

    DNA methylation and epigenetic inactivation of the O6-methylguanine methyltransferase (MGMT) gene induces MGMT deficiency, reducing the tumor cell’s DNA repair capacity and increasing its susceptibility to alkylating chemotherapeutic agents. Consequently, adult patients whose tumors are deficient in MGMT have better outcomes with alkylator chemotherapy, and MGMT methylation has been proposed as a screening marker of deficient tumors. In order to test the feasibility of this approach for medul...

  14. Effects of alpha-tocopherol on superoxide production and plasma intercellular adhesion molecule-1 and antibodies to oxidized LDL in chronic smokers

    NARCIS (Netherlands)

    Tits, van L.J.; Waart, de F.; Hak-Lemmers, H.L.M.; Heijst, P.; Graaf, de J.; Demacker, P.N.; Stalenhoef, A.F.

    2001-01-01

    Antioxidants have been postulated to exert beneficial effects in atherosclerosis. Atherosclerosis is associated with raised plasma levels of soluble intercellular adhesion molecule-1 (sICAM-1) and autoantibodies against oxidized low-density lipoprotein (oxLDL). It is not known whether antioxidants a

  15. The induction of stromule formation by a plant DNA-virus in epidermal leaf tissues suggests a novel intra- and intercellular macromolecular trafficking route

    Directory of Open Access Journals (Sweden)

    Björn eKrenz

    2012-12-01

    Full Text Available Stromules are dynamic thin protrusions of membrane envelope from plant cell plastids. Despite considerable progress in understanding the importance of certain cytoskeleton elements and motor proteins for stromule maintenance, their function within the cell has yet to be unraveled. Several viruses cause a remodulation of plastid structures and stromule biogenesis within their host plants. For RNA-viruses these interactions were demonstrated to be relevant to the infection process. An involvement of plastids and stromules is assumed in the DNA-virus life cycle as well, but their functional role needs to be determined. Recent findings support a participation of heat shock cognate 70 kDa protein (cpHSC70-1-containing stromules induced by a DNA-virus infection (Abutilon mosaic virus, AbMV, Geminiviridae in intra- and intercellular molecule exchange. The chaperone cpHSC70-1 was shown to interact with the AbMV movement protein (MP. Bimolecular fluorescence complementation confirmed the interaction of cpHSC70-1 and MP, and showed a homo-oligomerization of either protein in planta. The complexes were detected at the cellular margin and co-localized with plastids. In healthy plant tissues cpHSC70-1-oligomers occurred in distinct spots at chloroplasts and in small filaments extending from plastids to the cell periphery. AbMV-infection induced a cpHSC70-1-containing stromule network that exhibits elliptical dilations and transverses whole cells. Silencing of the cpHSC70-gene revealed an impact of cpHSC70 on chloroplast stability and restricted AbMV movement, but not viral DNA accumulation. Based on these data, a model is suggested in which these stromules function in molecule exchange between plastids and other organelles and perhaps other cells. AbMV may utilize cpHSC70-1 for trafficking along plastids and stromules into a neighboring cell or from plastids into the nucleus. Experimental approaches to investigate this hypothesis are discussed.

  16. Exenatide Alters Gene Expression of Neural Cell Adhesion Molecule (NCAM), Intercellular Cell Adhesion Molecule (ICAM), and Vascular Cell Adhesion Molecule (VCAM) in the Hippocampus of Type 2 Diabetic Model Mice.

    Science.gov (United States)

    Gumuslu, Esen; Cine, Naci; Ertan Gökbayrak, Merve; Mutlu, Oguz; Komsuoglu Celikyurt, Ipek; Ulak, Guner

    2016-01-01

    BACKGROUND Glucagon-like peptide-1 (GLP-1), a potent and selective agonist for the GLP-1 receptor, ameliorates the symptoms of diabetes through stimulation of insulin secretion. Exenatide is a potent and selective agonist for the GLP-1 receptor. Cell adhesion molecules are members of the immunoglobulin superfamily and are involved in synaptic rearrangements in the mature brain. MATERIAL AND METHODS The present study demonstrated the effects of exenatide treatment (0.1 µg/kg, subcutaneously, twice daily for 2 weeks) on the gene expression levels of cell adhesion molecules, neural cell adhesion molecule (NCAM), intercellular cell adhesion molecule (ICAM), and vascular cell adhesion molecule (VCAM) in the brain tissue of diabetic BALB/c male mice by real-time quantitative polymerase chain reaction (PCR). Diabetes was induced by streptozotocin/nicotinamide (STZ-NA) injection to male mice. RESULTS The results of this study revealed that hippocampal gene expression of NCAM, ICAM, and VCAM were found to be up-regulated in STZ-NA-induced diabetic mice compared to those of controls. A significant decrease in the gene expression levels of NCAM, ICAM, and VCAM were determined after 2 weeks of exenatide administration. CONCLUSIONS Cell adhesion molecules may be involved in the molecular mechanism of diabetes. Exenatide has a strong beneficial action in managing diabetes induced by STZ/NA by altering gene expression of NCAM, ICAM, and VCAM. PMID:27465247

  17. Analysis of fish bile with HPLC — fluorescence to determine environmental exposure to benzo(a)pyrene

    Science.gov (United States)

    Johnston, Eric P.; Baumann, Paul C.

    1989-01-01

    Brown bullhead from the Black River, Ohio, have a high incidence of liver neoplasia which is associated with elevated concentrations of polynuclear aromatic hydrocarbons (PAHs) in the sediment. We evaluated the use of biliary concentrations of benzo(a)pyrene [B(a)P] equivalents as a means for determining PAH exposure. Bile was collected from 16 brown bullheads and 8 common carp taken from each of two Lake Erie tributaries in Ohio, the industrialized Black River and the non-industrialized Old Woman Creek. Hatchery bullhead (n = 8) were used to determine base levels of PAHs. A high performance liquid chromatography (HPLC) — fluorescence technique was used to determine the concentration of B(a)P equivalents in the bile samples. The area of all peaks fluorescing at 380/430 nm was summed to give a single value for B(a)P equivalents in each sample. Concentrations of B(a)P equivalents generally reflected concentrations of PAH in sediment where fish were collected. Bile taken from Black River carp contained the highest concentration of B(a)P equivalents and was significantly different from all other groups. The value obtained for Black River bullhead was also high and was found to be significantly different from hatchery bullhead. B(a)P equivalents varied between carp and bullhead from the same habitat possibly because of differing food habits or metabolic pathways. However, our results indicate that relative levels of B(a)P equivalents in the bile of fish correspond well to B(a)P levels in sediment and may offer a means of determining environmental exposure of fish to the parent compound.

  18. Effect of benzo[a]pyrene on detoxification and the activity of antioxidant enzymes of marine microalgae

    Science.gov (United States)

    Shen, Chen; Miao, Jingjing; Li, Yun; Pan, Luqing

    2016-04-01

    The objective of this study was to examine the effect of benzo[a]pyrene (BaP) on the detoxification and antioxidant systems of two microalgae, Isochrysis zhanjiangensis and Platymonas subcordiformis. In our study, these two algae were exposed to BaP for 4 days at three different concentrations including 0.5 μg L-1 (low), 3 μg L-1 (mid) and 18 μg L-1 (high). The activity of detoxification enzymes, ethoxyresorufin O-deethylase (EROD) and glutathione S-transferase (GST) increased in P. subcordiformis in all BaP-treated groups. In I. zhanjiangensis, the activity of these two enzymes increased at the beginning of exposure, and then decreased in the groups treated with mid- and high BaP. The activity of antioxidant enzyme superoxide dismutase (SOD) increased in I. zhanjiangensis in all BaP-treated groups, and then decreased in high BaP-treated group, while no significant change was observed in P. subcordiformis. The activity of antioxidant enzyme catalase (CAT) increased in I. zhanjiangensis and P. subcordiformis in all BaPtreated groups. The content of malondialdehyde (MDA) in Isochrysis zhanjiangensis increased first, and then decreased in high BaP-treated group, while no change occurred in P. subcordiformis. These results demonstrated that BaP significantly influenced the activity of detoxifying and antioxidant enzymes in microalgae. The metabolic related enzymes (EROD, GST and CAT) may serve as sensitive biomarkers of measuring the contamination level of BaP in marine water.

  19. Biomarker responses in persian sturgeon (Acipenser persicus exposed to benzo-a-pyrene and beta-naphthoflavone

    Directory of Open Access Journals (Sweden)

    Karimzadeh Katayoon

    2013-01-01

    Full Text Available Biotransformation enzymes of xenobiotics (ethoxyresorufin-O-deethylase, cytochrome P4501A1 content and glutathione-S-transferase were investigated in the liver of Persian Sturgeon (Acipenser persicus after a 96-hour exposure to polycyclic aromatic hydrocarbons (PAHs, premutagenic benzo[a]pyrene (BaP and beta-naphthoflavone (BNF. The fish were injected 10 mg/kg wet-body weight in corn oil for 96 hours every days. Ethoxyresorufin-O-deethylase activity (EROD and glutathione s-transferase activity (GST were measured in the fish liver. Cytochrome P4501A1 (CYP1A1 content was estimated by indirect enzyme-linked immunosorbent assay (ELISA. The response appeared as early as 12 hours post exposure. A time-dependent response was observed in the EROD activity, being significantly higher at 48 hours post exposure to 10 mg/kg of BaP. The greatest induction occurred in the fish treated with 10 mg/kg BaP, in which a 32.1- fold increase in EROD activity was observed. Results showed that EROD activity in A. persicus is significantly increased by BaP and BNF treatments. Both chemicals showed higher values of EROD activity compared to the liver CYP1A content. There was a rise in glutathione-S-transferase activity in fish exposed to BNF, but no increase was observed in fish treated with BaP. The results showed that hepatic CYP1A expression in terms of induction of EROD activity might be suited as a biomarker of organic contamination in aquatic environments and led to lower sensitivity of the second phase in the detoxification enzyme.

  20. Dose-related carcinogenic effects of water-borne benzo(a)pyrene on livers of two small fish species

    Energy Technology Data Exchange (ETDEWEB)

    Hawkins, W.E.; Walker, W.W.; Overstreet, R.M.; Lytle, T.F.; Lytle, J.S.

    1988-12-01

    Benzo(a)pyrene (BaP) administered by water-borne exposures caused dose-related carcinogenic effects in livers of two small fish species, the Japanese medaka (Oryzias latipes) and the guppy (Poecilia reticulata). Medaka and guppies each were given two 6-h exposures. The first exposure was conducted on 6- to 10-day-old specimens. The second exposure was given 7 days later. The tests incorporated five treatment groups: (1) control, (2) carrier (dimethylformamide) control, (3) low BaP dose (not detectable--4 ppb), (4) intermediate BaP dose (about 8-47 ppb BaP), and (5) high BaP dose (200-270 ppb). Following the high-dose exposure, hepatocellular lesions classified as foci of cellular alteration (altered foci), adenomas, and hepatocellular carcinomas occurred in both species. In medaka, the lesions appeared to develop sequentially with the appearance of altered foci followed by adenomas and then hepatocellular carcinomas. Most lesions in guppies, however, were classified as altered foci although a few adenomas occurred in the early (24-week) sample and hepatocellular carcinomas occurred in the late (52-week) sample. When total lesions were combined, medaka had an 11% incidence at 24 weeks after the initial exposure and 36% incidence at 36 weeks. In guppies, 8% had liver lesions at 24 weeks, 19% at 36 weeks, and 20% at 52 weeks. A single extrahepatic neoplasm, a capillary hemangioma in a gill filament, occurred in a medaka from the 36-week high-dose sample. The results suggest that the medaka and guppy are capable of metabolizing water-borne BaP to carcinogenic metabolites which initiate hepatic tumor development.

  1. Transcriptomics responses in marine diatom Thalassiosira pseudonana exposed to the polycyclic aromatic hydrocarbon benzo[a]pyrene.

    Directory of Open Access Journals (Sweden)

    Raquel N Carvalho

    Full Text Available Diatoms are unicellular, photosynthetic, eukaryotic algae with a ubiquitous distribution in water environments and they play an important role in the carbon cycle. Molecular or morphological changes in these species under ecological stress conditions are expected to serve as early indicators of toxicity and can point to a global impact on the entire ecosystem. Thalassiosira pseudonana, a marine diatom and the first with a fully sequenced genome has been selected as an aquatic model organism for ecotoxicological studies using molecular tools. A customized DNA microarray containing probes for the available gene sequences has been developed and tested to analyze the effects of a common pollutant, benzo(apyrene (BaP, at a sub-lethal concentration. This approach in diatoms has helped to elucidate pathway/metabolic processes involved in the mode of action of this pollutant, including lipid metabolism, silicon metabolism and stress response. A dose-response of BaP on diatoms has been made and the effect of this compound on the expression of selected genes was assessed by quantitative real time-PCR. Up-regulation of the long-chain acyl-CoA synthetase and the anti-apoptotic transmembrane Bax inhibitor, as well as down-regulation of silicon transporter 1 and a heat shock factor was confirmed at lower concentrations of BaP, but not the heat-shock protein 20. The study has allowed the identification of molecular biomarkers to BaP to be later on integrated into environmental monitoring for water quality assessment.

  2. Degradation of metabolites of benzo[a]pyrene by coupling Penicillium chrysogenum with KMnO4

    Institute of Scientific and Technical Information of China (English)

    ZANG Shu-yan; LI Pei-jun; YU Xiao-cai; SHI Kun; ZHANG Hui; CHEN Jing

    2007-01-01

    Several main metabolites of benzo[a]pyrene (BaP) formed by Penicillium chrysogenum, Benzo[a]pyrene-l,6-quinone (BP 1,6-quinone), trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (BP 7,8-diol), 3-hydroxybenzo[a]pyrene (3-OHBP), were identified by high-performance liquid chromatography (HPLC). The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized.The results showed that (1) the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; (2) the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; (3) the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% (w/v), concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites.

  3. Electroporation loading of membrane-impermeable molecules to investigate intra- and intercellular Ca2+ signaling.

    Science.gov (United States)

    Decrock, Elke; De Bock, Marijke; Wang, Nan; Bol, Mélissa; Gadicherla, Ashish K; Leybaert, Luc

    2015-03-02

    Electroporation is a technique that temporarily induces pores in the plasma membranes of cells, thereby allowing plasma membrane-impermeable substances to enter the cells. This loading method requires an electrical drive circuit providing an electroporation signal, an electrode to apply the signal to a localized zone in a cell monolayer, and a special solution that has a low electrical conductivity. To avoid impairment of cell function and cell death from the electroporation procedure itself, the applied electrical signal should ideally be a high-frequency oscillating signal (50 kHz) without any direct current (DC) component. Here, we describe the detailed procedure of electroporation loading.

  4. Comparative in vitro metabolism and activation of benzo(a)pyrene from two species of catfish

    Energy Technology Data Exchange (ETDEWEB)

    Ploch, S.A.; Di Giulio, R.T. [Duke Univ., Durham, NC (United States)

    1995-12-31

    Cytochrome P4501A activity as measured by hepatic ethoxyresorufin-O-deethylase EROD in isolated microsomes is consistently found to be 10 to 20 fold higher in channel catfish (Ictalurus punctuatus) than in a closely related species of catfish, the brown bullhead (Ameriurus nebulosus). To measure more directly the ability of these two species to activate a model PAH, microsomes and hepatocytes isolated from naphthoflavone induced channel catfish (CC) and brown bullhead (BB) were incubated with [{sup 3}H]- or [{sup 14}C]benzo(a)pyrene (BP) to compare metabolite formation and binding to DNA and protein. Microsomes from channel catfish produce 4-fold higher levels of BP metabolites (hexane non-extractable) than brown bullhead (253.0, 9.0 vs 58.8, 14.9 pmole/mg, protein/min). Binding of microsome activated BP to salmon sperm DNA demonstrated a similar 5-fold difference between the two species. Using isolated hepatocytes, the two species demonstrated less pronounced, but consistent differences in metabolite formation (29.85, 2.2 vs 20.1, 0.96 pmole/10{sup 6}, cells/min, CC vs BB), DNA binding and total protein binding (13.2, 2.53 vs 10.57, 1.72 pmole BP/mg, protein/min, CC vs BB). Surprisingly, these preliminary data suggest that induced CC liver activate a model PAH carcinogen more quickly and produce higher levels of stable adducts than a cancer prone species (brown bullhead). Other aspects of BP activation, detoxification and genotoxicity in these two species may contribute to species` susceptibility to carcinogenesis.

  5. Induction of micronuclei by X radiation and various chemical agents in red blood cells of Pleurodeles waltl. Uptake, release and excretion of one of them: benzo(a)pyrene

    International Nuclear Information System (INIS)

    The first part of the study is concerned with the effects of X radiation and of various substances dissolved in the breeding water (carbaryl, N-nitrosocarbaryl, benzo(a)pyrene, formol, cafeine, colchicine...) on the formation of micronuclei in red blood cells of Pleurodele larvae. The curves of the dose-effect relationships and of the kinetics of micronuclei formation are established for X radiation and benzo(a)pyrene. In the second part, a scintigraphic study concerning benzo(a)pyrene uptake, release and excretion by larvae, is presented. This study enables the dose-effect curve and the kinetics of micronuclei formation for this substance, to be interpreted. This study must allow the development of a cytogenetic test for the detection of radiomimetic substances in aqueous medium. Pleurodele is proposed as a new animal for the study of genetic toxicology

  6. Neuropeptides stimulate human osteoblast activity and promote gap junctional intercellular communication.

    Science.gov (United States)

    Ma, Wenhui; Zhang, Xuemin; Shi, Shushan; Zhang, Yingze

    2013-06-01

    Neuropeptides released from the skeletal nerve fibers have neurotransmitter and immunoregulatory roles; they exert paracrine biological effects on bone cells present close to the nerve endings expressing these signaling molecules. The aims of this study were a systematic investigation of the effects of the neuropeptides substance P (SP), calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide (VIP), Neuropeptide Y (NPY) and tyrosine hydroxylase (TH) on the cell viability and function of the human osteoblasts, and comparing their difference in the role of regulating bone formation. Cultures of normal human osteoblasts were treated with SP, CGRP, VIP, NPY or TH at three concentrations. We found that each of the five neuropeptides induced increases in cell viability of human osteoblasts. The stimulatory action of NPY was the highest, followed by VIP, SP and TH, while CGRP had the lowest stimulatory effect. The viability index of osteoblasts was inversely associated with the concentration of neuropeptides, and positively with the time of exposure. Moreover, the five neuropeptides increased the ALP activity and osteocalcin to different extents in a dose-dependent manner. The GJIC of osteoblasts was significantly promoted by neuropeptides. The results demonstrated that neuropeptides released from skeletal nerve endings after a stimulus appeared to be able to induce the proliferation and activity of osteoblasts via enhancing GJIC between cells, and further influence the bone formation. These findings may contribute toward a better understanding of the neural influence on bone remodeling and improving treatments related to bone diseases.

  7. Base substitution mutations induced by metabolically activated aflatoxin B1.

    Science.gov (United States)

    Foster, P L; Eisenstadt, E; Miller, J H

    1983-05-01

    We have determined the base substitutions generated by metabolically activated aflatoxin B1 in the lacI gene of a uvrB- strain of Escherichia coli. By monitoring over 70 different nonsense mutation sites, we show that activated aflatoxin B1 specifically induced GxC leads to TxA transversions. One possible pathway leading to this base change involves depurination at guanine residues. We consider this mechanism of mutagenesis in the light of our other findings that the carcinogens benzo[a]pyrene diol epoxide and N-acetoxyacetylaminofluorene also specifically induce GxC leads to TxA transversions. PMID:6405385

  8. Keratin expression in chemically induced mouse lung adenomas.

    OpenAIRE

    Gunning, W T; Goldblatt, P. J.; Stoner, G D

    1992-01-01

    Chemically induced mouse lung tumors exhibit distinctive growth patterns, characterized by an alveolar or solid appearance, a papillary appearance, or a combination of the two. Lung tumors induced in strain A/J mice by either benzo(a)pyrene (BP) or by N-nitrosoethylurea (ENU) were examined for expression of low- and high-molecular-weight cytokeratins. Simple cytokeratins (low molecular weight) were found in all epithelial cells of the normal mouse lung and in all tumor types, whereas higher-m...

  9. Mikrosomale Biotransformation von Benzo[ghi]perylen, einem mutagenen polyaromatischen Kohlenwasserstoff ohne das Strukturelement der Bay-Region des kanzerogenen Benzo[a]pyrens

    OpenAIRE

    Grupe, Stefanie

    2005-01-01

    Kanzerogene polyaromatische Kohlenwasserstoffe (PAKs), wie Benzo[a]pyren, besitzen eine Bay-Region mit ortho-kondensiertem Benzoring. Dadurch ist die enzymatische Bildung von Bay-Region-Dihydrodiolepoxiden (Oxiranylring in der sterisch abgeschirmten Molekülbucht) möglich, die als ultimal kanzerogene Metaboliten der PAKs gelten. Diese lösen durch DNA-Modifikation Primärläsionen aus, die, sofern sie nicht enzymatisch repariert werden, bei der DNA-Replikation Fehler verursachen (Mu-tationen). De...

  10. Detection of benzo[a]pyrene diol epoxide-DNA adducts in peripheral blood lymphocytes and antibodies to the adducts in serum from coke oven workers.

    OpenAIRE

    Harris, C. C.; Vahakangas, K.; Newman, M J; Trivers, G E; Shamsuddin, A; Sinopoli, N; Mann, D L; Wright, W. E.

    1985-01-01

    Coke oven workers are exposed to high levels of carcinogenic polycyclic aromatic hydrocarbons, including benzo[a]pyrene (B[a]P), and are at increased risk of lung cancer. Since B[a]P is enzymatically activated to 7 beta,8 alpha-dihydroxy(9 alpha, 10 alpha)epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (B[a]PDE) that forms adducts with DNA, the presence of these adducts was measured in DNA from peripheral blood lymphocytes by synchronous fluorescence spectrophotometry and enzyme radioimmunoassay. App...

  11. Metabolism of benzo(a)pyrene, N-nitrosomethylamine, and N-nitrosopyrrolidine and identification of the major carcinogen-DNA adducts formed in cultured human esophagus

    DEFF Research Database (Denmark)

    1979-01-01

    The wide variation in the world-wide incidence of esophageal carcinoma suggests that environmental agents including chemicals cause this cancer. Since the interaction between chemical procarcinogens and human esophagus has not been studied previously, we examined the metabolic fate of benzo......(a)pyrene (BP), N-nitrosodimethylamine (DMN), and A/-nitrosopyrrolidine in cultured nontumorous esophagus from two patients with and six patients without esophageal carcinoma. Esophageal explants were cultured in a chemically defined medium for 7 days prior to adding [3H]BP (1.5 JUM),[14C]DMN (100 /IM), or [14C...

  12. Efflux of potassium ion is an important reason of HL-60 cells apoptosis induced by tachyplesin

    Institute of Scientific and Technical Information of China (English)

    Hai-tao ZHANG; Jun WU; Hai-feng ZHANG; Qi-feng ZHU

    2006-01-01

    Aim: To investigate the role of intercellular potassium in tachyplesin-induced HL-60 cells apoptosis. Methods: The concentration of intercellular potassium, cell volume and mitochondrial membrane potential were examined by flow cytometry. Results: The concentration of intercellular potassium reduced in a time-dependent manner in tachyplesin-treated HL-60 cells. In addition, the loss of mitochondrial membrane potential was tightly coupled with the shrinkage of cell volume. Different caspase inhibitors protected against DNA degradation but did not prevent the loss of HL-60 cell viability induced by tachyplesin. Ba2+, which was a kind of blocker of volume-regulatory K+ channels, increased the viability of tachyplesin-treated HL-60 cells and maintained mitochondrial membrane potential and cell volume. Conclusion: Efflux of K+ was an important reason for apoptosis in tachyplesin-treated HL-60 cells. Efflux of K+ affected the viability of tachyplesin-treated HL-60 cells independent of the process of caspase activation.

  13. Effects of garlic oil on tumoragenecity and intercellular communication in human gastric cancer cell line

    Institute of Scientific and Technical Information of China (English)

    李晓光; 谢锦玉; 李文梅; 季加孚; 崔建涛; 赵敏; 孙梅; 吕有勇

    2000-01-01

    Previous studies have demonstrated that garlic oil (GO) and its anti-tumor compound could inhibit DNA and RNA synthesis in human cancer cells. In order to explore the effects of garlic oil on carcinoma cells, a gastric carcinoma cell line, BGC-823 was studied at cellular and molecular levels after garlic oil treatment. Data showed that the cell differentiation and suppression of tumorigenicity were significantly induced in tumor cells after garlic oil treatment. There was a correlation between the cell-cell communication recovery and the increase of p53 and waf1/p21 gene expression in garlic oil-treated cells. This result suggested that tumor suppressor gene waf1/p21 and wt p53 might play an important role in this effect.

  14. Effects of garlic oil on tumoragenecity and intercellular communication in human gastric cancer cell line

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Previous studies have demonstrated that garlic oil (GO) and its anti-tumor compound could inhibit DNA and RNA synthesis in human cancer cells.In order to explore the effects of garlic oil on carcinoma cells,a gastric carcinoma cell line,BGC-823 was studied at cellular and molecular levels after garlic oil treatment.Data showed that the cell differentiation and suppression of tumorigenicity were significantly induced in tumor cells after garlic oil treatment.There was a correlation between the cell-cell communication recovery and the increase of p53 and waf1/p21 gene expression in garlic oil-treated cells.This result suggested that tumor suppressor gene waf1/p21 and wt p53 might play an important role in this effect.

  15. Hematopoiesis: Gap Junction Intercellular Communication is Likely to be Involved in Regulation of Stroma-dependent Proliferation of Hemopoietic Stem Cells.

    Science.gov (United States)

    Ploemacher, ROB E.; Mayen, ANGELIQUE E. M.; De Koning, ALEXANDRA E.; Krenacs, TIBOR; Rosendaal, MARTIN

    2000-01-01

    The 80-100 fold increased immunohistological expression of the Gap Junction (GJ) protein Connexin-43 in murine bone marrow during the neonatal period and directly following cytoreductive treatment of adult mice suggests that the regulation of stem cell proliferation may involve GJ Intercellular Communication (GJIC). Using a series of stromal cell lines from foetal liver and neonatal bone marrow we observed that the percentage of cells with GJIC, as indicated by dye-coupling using microinjection of lucifer yellow, correlated with the stromal support for late appearing clones formed by primitive stem cells (CAFC week 3-5). In order to functionally block all GJIC between mutual stromal cells and stromal cells and hemopoietic cells, in long-term stroma-supported flask (LTC) and CAFC cultures, the lipophilic compounds amphotericin-B (AB), nystatin, alpha-glycyrrhetinic acid, tetraphenylboron, dipicrylamine and arachidonic acid were tested for their effect on GJIC and CAFC support. Only AB and nystatin, which induced complete and prolonged GJIC blockade, were able to dramatically inhibit cobblestone area (CA) formation and CFU-C generation in LTC. This inhibition could be fully abrogated by withdrawing AB within the first 2 weeks of culture. Low AB concentrations stimulated CA formation. The AB-mediated inhibition of hemopoiesis probably involved direct stromal contact with stem cells because a) AB did not inhibit CFU-C generation when stem cells were cultured in trans-well inserts above the stroma; b) conditioned media from AB-containing or normal LTC did not inhibit colony formation by normal cells in semi-solid, non-stromal cultures, and c) AB did not inhibit colony formation by bone marrow cells in semi-solid culture nor did it inhibit growth or maintenance of stromal cells. In addition, The inhibition of hemopoiesis by AB could also not be explained by changes in the amount of cytokine and chemokine transcripts, including TGF-b1, in AB-blocked stromal cells. Our

  16. Modulation of adult rat benzo(a)pyrene (BaP) metabolism and DNA adduct formation by neonatal diethylstilbestrol (DES) exposure.

    Science.gov (United States)

    Ramesh, Aramandla; Inyang, Frank; Knuckles, Maurice E

    2004-12-01

    This study seeks to elucidate the role of diethylstilbestrol (DES), a synthetic estrogen on benzo(a)pyrene (BaP) metabolism in the male rat reproductive tissues. Offspring of timed-pregnant Sprague-Dawley rats were neonatally treated on days 2, 4, and 6 post-partum with 1.45 micromol/kg of DES. Ten weeks after birth, the adult rats were challenged with radiolabeled benzo(a)pyrene (3H BaP) (10 micromol/kg) and the rats were sacrificed 2 h after BaP exposure. Prostrate, testis, lung, liver, urine and feces samples were collected and extracted using a mixture of H2O, MeOH and CHCl3. The extracts were analyzed by reverse phase HPLC. The concentrations of BaP organic metabolites in DES rats were lower compared to controls (vehicle-treated rats). On the other hand, concentrations of aqueous metabolites were significantly increased in DES treated animals. The toxication to detoxication ratios were significantly decreased in DES rats compared to controls. This trend is also reflected in the decreased concentrations of BaP-DNA adducts in DES rats. Collectively these results suggest that DES is capable of modulating the metabolic pathway of BaP towards detoxification thereby preventing the manifestation of toxicity.

  17. Effect of perfluorooctane sulfonate on viability, maturation and gap junctional intercellular communication of porcine oocytes in vitro.

    Science.gov (United States)

    Domínguez, A; Salazar, Z; Arenas, E; Betancourt, M; Ducolomb, Y; González-Márquez, H; Casas, E; Teteltitla, M; Bonilla, E

    2016-09-01

    Perfluorooctane sulfonate (PFOS) is a broadly used man-made surfactant whose long half-life has led to bioaccumulation. This perfluorinated compound is ubiquitous in human body fluids. PFOS concentrations as high as 26μM in plasma have been reported in occupationally exposed populations, and high levels of PFOS in human follicular fluid have been associated with subfertility. However, the effect of PFOS on the maturation of oocytes in mammals has not been reported to date. The aim of this study was to determine the effects of PFOS during oocyte maturation. Results indicate that PFOS inhibits oocyte viability (Lethal Concentration50=32μM) and maturation (inhibition of maturation50=22μM) at physiologically relevant concentrations. In order to evaluate the mechanisms of oocyte maturation inhibition by PFOS, gap junctional intercellular communication (GJIC) between oocytes and granulosa cells was assessed. GJIC between granulosa cells and the oocyte was significantly affected during the first 8h of maturation. However, the inhibitory effect of PFOS on GJIC was not due to an alteration on the expression of connexin genes Cx43, Cx45 and Cx60. These findings suggest that occupationally exposed populations could be at risk, and that PFOS might affect oocyte maturation by interfering the GJIC in the cumulus-oocyte complexes during the first hours of maturation. PMID:27233358

  18. To Gate, or Not to Gate: Regulatory Mechanisms for Intercellular Protein Transport and Virus Movement in Plants

    Institute of Scientific and Technical Information of China (English)

    Shoko Ueki; Vitaly Citovsky

    2011-01-01

    Cell-to-cell signal transduction is vital for orchestrating the whole-body physiology of multi-cellular organisms,and many endogenous macromolecules,proteins,and nucleic acids function as such transported signals.In plants,many of these molecules are transported through plasmodesmata (Pd),the cell wall-spanning channel structures that interconnect plant cells.Furthermore,Pd also act as conduits for cell-to-cell movement of most plant viruses that have evolved to pirate these channels to spread the infection.Pd transport is presumed to be highly selective,and only a limited repertoire of molecules is transported through these channels.Recent studies have begun to unravel mechanisms that actively regulate the opening of the Pd channel to allow traffic.This macromolecular transport between cells comprises two consecutive steps:intracellular targeting to Pd and translocation through the channel to the adjacent cell.Here,we review the current knowledge of molecular species that are transported though Pd and the mechanisms that control this traffic.Generally,Pd traffic can occur by passive diffusion through the trans-Pd cytoplasm or through the membrane/lumen of the trans-Pd ER,or by active transport that includes protein-protein interactions.It is this latter mode of Pd transport that is involved in intercellular traffic of most signal molecules and is regulated by distinct and sometimes interdependent mechanisms,which represent the focus of this article.

  19. A mutual support mechanism through intercellular movement of CAPRICE and GLABRA3 can pattern the Arabidopsis root epidermis.

    Science.gov (United States)

    Savage, Natasha Saint; Walker, Tom; Wieckowski, Yana; Schiefelbein, John; Dolan, Liam; Monk, Nicholas A M

    2008-09-23

    The patterning of the Arabidopsis root epidermis depends on a genetic regulatory network that operates both within and between cells. Genetic studies have identified a number of key components of this network, but a clear picture of the functional logic of the network is lacking. Here, we integrate existing genetic and biochemical data in a mathematical model that allows us to explore both the sufficiency of known network interactions and the extent to which additional assumptions about the model can account for wild-type and mutant data. Our model shows that an existing hypothesis concerning the autoregulation of WEREWOLF does not account fully for the expression patterns of components of the network. We confirm the lack of WEREWOLF autoregulation experimentally in transgenic plants. Rather, our modelling suggests that patterning depends on the movement of the CAPRICE and GLABRA3 transcriptional regulators between epidermal cells. Our combined modelling and experimental studies show that WEREWOLF autoregulation does not contribute to the initial patterning of epidermal cell fates in the Arabidopsis seedling root. In contrast to a patterning mechanism relying on local activation, we propose a mechanism based on lateral inhibition with feedback. The active intercellular movements of proteins that are central to our model underlie a mechanism for pattern formation in planar groups of cells that is centred on the mutual support of two cell fates rather than on local activation and lateral inhibition.

  20. A mutual support mechanism through intercellular movement of CAPRICE and GLABRA3 can pattern the Arabidopsis root epidermis.

    Directory of Open Access Journals (Sweden)

    Natasha Saint Savage

    2008-09-01

    Full Text Available The patterning of the Arabidopsis root epidermis depends on a genetic regulatory network that operates both within and between cells. Genetic studies have identified a number of key components of this network, but a clear picture of the functional logic of the network is lacking. Here, we integrate existing genetic and biochemical data in a mathematical model that allows us to explore both the sufficiency of known network interactions and the extent to which additional assumptions about the model can account for wild-type and mutant data. Our model shows that an existing hypothesis concerning the autoregulation of WEREWOLF does not account fully for the expression patterns of components of the network. We confirm the lack of WEREWOLF autoregulation experimentally in transgenic plants. Rather, our modelling suggests that patterning depends on the movement of the CAPRICE and GLABRA3 transcriptional regulators between epidermal cells. Our combined modelling and experimental studies show that WEREWOLF autoregulation does not contribute to the initial patterning of epidermal cell fates in the Arabidopsis seedling root. In contrast to a patterning mechanism relying on local activation, we propose a mechanism based on lateral inhibition with feedback. The active intercellular movements of proteins that are central to our model underlie a mechanism for pattern formation in planar groups of cells that is centred on the mutual support of two cell fates rather than on local activation and lateral inhibition.

  1. Expression of intercellular adhesion molecule-1 in UVA-irradiated human skin cells in vitro and in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Treina, G.; Scaletta, C.; Frenk, E.; Applegate, L.A. [University Hospital-CHUV, Lausanne (Switzerland). Laboratory of Photobiology; Fourtanier, A.; Seite, S. [L`Oreal-Centre de Recherche Charles Zviak (France). Recherche Avancee Biologie

    1996-08-01

    Ultraviolet A (UVA) radiation represents an important oxidative stress to human skin and certain forms of oxidative stress have been shown to modulate intercellular adhesion molecule-1 (ICAM-1) expression. ICAM-1 has been shown to play an important part in many immune reactions and the perturbations of this molecule by ultraviolet radiation could have implications in many inflammatory responses. An enhancement immunohistochemical method with avidin/biotin was used for analysing the early effects of UVA radiation on human cell cultures and human skin (340-400 nm). Both in vitro and in vivo data show that ICAM-1 staining in epidermal keratinocytes, which was expressed constitutively, decreased in a UVA dose-dependent manner. The decrease was most noted at 3-6 h following UVA radiation with some ICAM-1 staining returning by 48 h post-UVA. ICAM-1 positive staining in the dermis was specific for vascular structures and was increased 24 h after UVA radiation. Cultured dermal fibroblasts exhibited ICAM-1 staining which increased slightly within 6-48 h post-UVA radiation. As epidermal ICAM-1 expression is depleted following UVA radiation and dermal expression increases due to an increase in the vascular structures, ICAM-1 provides a valuable marker following UVA radiation in human skin that can be readily measured in situ. (author).

  2. Zwitterionic pH/redox nanoparticles based on dextran as drug carriers for enhancing tumor intercellular uptake of doxorubicin.

    Science.gov (United States)

    Wu, Luyan; Zhang, Liping; Shi, Gang; Ni, Caihua

    2016-04-01

    Zwitterionic nanoparticles have excellent serum stability. In this study, pH/redox responsive polymer was synthesized through a modification of dextran using succinic acid, followed by crosslinking with cystamine. The polymer could self-assemble into stable nanoparticles (NPs) in aqueous solution. The NPs carried certain amount of free carboxyl and amino groups on the surface, which endowed the NPs excellent anti-protein adsorption ability. The surface charge was negative at pH7.4 and was converted to positive at pH5.0. It was revealed that the NPs showed little non-specific protein adsorption and had excellent serum stability, and the NPs could be internalized in Hela cells rapidly. This result was ascribed to the charge reversible feature of the NPs. Doxorubicin (DOX) was loaded in the NPs for release studies in vitro. The DOX-loaded NPs exhibited obvious pH and reduction sensitivities in response to the environment in tumor cells due to the introduction of carboxyl groups, amino groups and disulfide bonds in the NPs. The NPs were biocompatible, biodegradable, and could be potentially applied as anticancer drug carriers for enhancement of tumor intercellular uptake of doxorubicin. PMID:26838851

  3. Transposon-Based Reporter Marking Provides Functional Evidence for Intercellular Bridges in the Male Germline of Rabbits.

    Directory of Open Access Journals (Sweden)

    Orsolya I Hoffmann

    Full Text Available The Sleeping Beauty transposon system was established as a robust and efficient method for germline transgenesis in different mammalian species. The generation of transgenic mice, rats, rabbits and swine carrying an identical Venus reporter construct delivered by transposon-mediated gene transfer enables comparative studies of gene expression in these lines of mammalian models. Whereas comparable expression patterns of the Venus reporter were found in somatic tissues, preliminary studies suggested that a striking difference in reporter expression may exist in mature spermatozoa of these species. Here we clearly show the differential expression of Venus reporter protein during spermatogenesis of the two compared species, the laboratory rabbit and mice. We provide evidence for the functionality of intercellular bridges in the male germline and genotype-independent transgenic phenotype of rabbit spermatids. Our data suggest that the reporter rabbit line may be a suitable tool to identify molecular mechanisms in testicular development, and may contribute to develop better animal models for male infertility in men.

  4. Mobility of the native Bacillus subtilis conjugative plasmid pLS20 is regulated by intercellular signaling.

    Science.gov (United States)

    Singh, Praveen K; Ramachandran, Gayetri; Ramos-Ruiz, Ricardo; Peiró-Pastor, Ramón; Abia, David; Wu, Ling J; Meijer, Wilfried J J

    2013-10-01

    Horizontal gene transfer mediated by plasmid conjugation plays a significant role in the evolution of bacterial species, as well as in the dissemination of antibiotic resistance and pathogenicity determinants. Characterization of their regulation is important for gaining insights into these features. Relatively little is known about how conjugation of Gram-positive plasmids is regulated. We have characterized conjugation of the native Bacillus subtilis plasmid pLS20. Contrary to the enterococcal plasmids, conjugation of pLS20 is not activated by recipient-produced pheromones but by pLS20-encoded proteins that regulate expression of the conjugation genes. We show that conjugation is kept in the default "OFF" state and identified the master repressor responsible for this. Activation of the conjugation genes requires relief of repression, which is mediated by an anti-repressor that belongs to the Rap family of proteins. Using both RNA sequencing methodology and genetic approaches, we have determined the regulatory effects of the repressor and anti-repressor on expression of the pLS20 genes. We also show that the activity of the anti-repressor is in turn regulated by an intercellular signaling peptide. Ultimately, this peptide dictates the timing of conjugation. The implications of this regulatory mechanism and comparison with other mobile systems are discussed. PMID:24204305

  5. The effects of anthracene and methylated anthracenes on gap junctional intercellular communication in rat liver epithelial cells.

    Science.gov (United States)

    Upham, B L; Weis, L M; Rummel, A M; Masten, S J; Trosko, J E

    1996-12-01

    Polycyclic aromatic hydrocarbons (PAHs), many of which are known carcinogens, are derived from the pyrolysis of organic materials. A rich source of PAHs is cigarette smoke, which contains methylated anthracenes and phenanthrenes as the predominant PAHs. The tumor-promoting activity of cigarette smoke has been well documented. The down-regulation of gap junction intercellular communication (GJIC) by nongenotoxic chemicals and several oncogenes has been implicated in tumor promotion. Therefore, we determined the effects of the three isomers of methylanthracene on GJIC in WB-F344 rat liver epithelial cells. Anthracene and 2-methylanthracene did not significantly inhibit GJIC, whereas anthracene methylated in the 1 or 9 position reversibly inhibited GJIC with I50 values of 22 and 36 microM, respectively. Inhibition occurred within 15 min. In conclusion, the biological effect of methylanthracene depends on the ring position of the methyl group, and these inhibitory isomers could play a potential role in tumor promotion of methylated PAH-rich mixtures such as cigarette smoke and crude oil products. PMID:8954755

  6. Impact of benzo(a)pyrene, Cu and their mixture on the proteomic response of Mytilus galloprovincialis

    Energy Technology Data Exchange (ETDEWEB)

    Maria, V.L., E-mail: vmaria@ualg.pt [CIMA, Faculty of Sciences and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Gomes, T., E-mail: tcgomes@ualg.pt [CIMA, Faculty of Sciences and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Barreira, L., E-mail: lbarreir@ualg.pt [CCMAR, Faculty of Sciences and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Bebianno, M.J., E-mail: mbebian@ualg.pt [CIMA, Faculty of Sciences and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

    2013-11-15

    Highlights: •Distinct protein expression profiles dependent of BaP and Cu accumulation, metabolism and chemical interactions in mussels, Mytilus galloprovincialis. •Processes that involve adhesion and motility, cytoskeleton and cell structure, stress response, transcription regulation and energy metabolism are common mechanisms. •Traditional (ATP synthase, GST, HSP and actin) and novel biomarkers for BaP (ZFP), Cu (chitin synthase) and mixture (MVP) exposures identified in mussels. -- Abstract: In natural waters, chemical interactions between mixtures of contaminants can result in potential synergistic and/or antagonic effects in aquatic animals. Benzo(a)pyrene (BaP) and copper (Cu) are two widespread environmental contaminants with known toxicity towards mussels Mytilus spp. The effects of the individual and the interaction of BaP and Cu exposures were assessed in mussels Mytilus galloprovincialis using proteomic analysis. Mussels were exposed to BaP [10 μg L{sup −1} (0.396 μM)], and Cu [10 μg L{sup −1} (0.16 μM)], as well as to their binary mixture (mixture) for a period of 7 days. Proteomic analysis showed different protein expression profiles associated to each selected contaminant condition. A non-additive combined effect was observed in mixture in terms of new and suppressed proteins. Proteins more drastically altered (new, suppressed and 2-fold differentially expressed) were excised and analyzed by mass spectrometry, and eighteen putatively identified. Protein identification demonstrated the different accumulation, metabolism and chemical interactions of BaP, Cu and their mixture, resulting in different modes of action. Proteins associated with adhesion and motility (catchin, twitchin and twitchin-like protein), cytoskeleton and cell structure (α-tubulin and actin), stress response (heat shock cognate 71, heat shock protein 70, putative C1q domain containing protein), transcription regulation (zinc-finger BED domain-containing and nuclear

  7. Determinação de benzo(apireno em pescados Determination of benzo(apyrene in fish products

    Directory of Open Access Journals (Sweden)

    Antonio Azeredo

    2006-03-01

    Full Text Available No presente estudo, peixes, camarões, mexilhões e carnes de siri frescos e processados, comercializados na região metropolitana de Campinas (SP, foram analisados quanto à presença de benzo(apireno (B(aP. A metodologia utilizada envolveu extração com n-hexano, limpeza em Sep-Pak sílica plus e determinação por Cromatografia Líquida de Alta Eficiência com Detector de Fluorescência. A presença de B(aP foi detectada em todas as amostras analisadas (n=35, em quantidades variando na faixa de 0,03 a 4,54 µg/kg. Os maiores níveis de contaminação foram encontrados em produtos defumados (níveis médios=2,5 µg/kg e mexilhões (níveis médios=2,4 µg/kg. Considerando-se o potencial carcinogênico desse contaminante e a importância desse grupo de alimentos na dieta, um programa de monitoramento deve ser iniciado para identificar e controlar a fonte de contaminação de pescados por B(aP.In the present study samples of fresh and processed fish, shrimp, mussels and crab meat commercialized in the metropolitan area of Campinas (SP, Brazil were analysed for benzo(apyrene (B(aP. The methodology involved extraction with n-hexane, clean-up on Sep-Pak silica plus and determination by High Performance Liquid Chromatography with a Fluorescence Detector. B(aP was detected in all samples analysed (n=35 at levels ranging from to 0.03 a 4.54 µg/kg. The highest content of B(aP was found in smoked products (mean level=2.5 µg/kg and mussels (mean level=2.4 µg/kg. In view of the carcinogenic potential of this widely distributed contaminant and the importance of seafood in the daily diet of fisherman communities, a monitoring program should be initiated to identify and control the source of contamination of seafood by B(aP.

  8. Expression of intercellular adhesion molecule-1 in rat heart with ischemia/reperfusion and limitation of infarct size by treatment with antibodies against cell adhesion molecules.

    OpenAIRE

    Yamazaki, T; Seko, Y; Tamatani, T; Miyasaka, M.; Yagita, H; Okumura, K.; R. Nagai; Yazaki, Y

    1993-01-01

    To elucidate the mechanism(s) of myocardial reperfusion injury, we investigated the roles of cell adhesion molecules on both leukocytes and vascular endothelial cells in the reperfused myocardia. We found that within 2 hours after reperfusion leukocytes began to infiltrate into the rat myocardia subjected to 30 minutes of ischemia and clarified, for the first time, that the expression of intercellular adhesion molecule-1 was enhanced on the capillary and venous endothelial cells from 8 to 96 ...

  9. Low Connexin Channel-Dependent Intercellular Communication in Human Adult Hematopoietic Progenitor/Stem Cells: Probing Mechanisms of Autologous Stem Cell Therapy

    OpenAIRE

    Yang, Jian; Darley, Richard L.; Hallett, Maurice; Evans, W. Howard

    2010-01-01

    Human bone marrow is a clinical source of autologous progenitor stem cells showing promise for cardiac repair following ischemic insult. Functional improvements following delivery of adult bone marrow CD34+ cells into heart tissue may require metabolic/electrical communication between participating cells. Since connexin43 (Cx43) channels are implicated in cardiogenesis and provide intercellular connectivity in the heart, the authors analyzed the expression of 20 connexins (Cx) in CD34+ cells ...

  10. The effect of antidiuretic stimuli on the morphology of the lateral intercellular spaces in the medullary collecting duct of the rat.

    OpenAIRE

    Rowen, D; Law, R O

    1981-01-01

    An investigation has been carried out into the formation of dilated lateral intercellular spaces in the medullary collecting duct of the rat kidney following water deprivation or infusion of vasopressin. Dilation is conspicuous under these conditions, by comparison with normally hydrated controls, but its appearance is prevented by prior treatment of rats with antiserum raised against urinary (renal) hyaluronidase. Antiserum against testicular hyaluronidase is without effect. The presence or ...

  11. The Analysis of Intracellular and Intercellular Calcium Signaling in Human Anterior Lens Capsule Epithelial Cells with Regard to Different Types and Stages of the Cataract.

    Directory of Open Access Journals (Sweden)

    Marko Gosak

    Full Text Available In this work we investigated how modifications of the Ca2+ homeostasis in anterior lens epithelial cells (LECs are associated with different types of cataract (cortical or nuclear and how the progression of the cataract (mild or moderate affects the Ca2+ signaling. We systematically analyzed different aspects of intra- and inter-cellular Ca2+ signaling in the human LECs, which are attached to surgically isolated lens capsule (LC, obtained during cataract surgery. We monitored the temporal and spatial changes in intracellular Ca2+ concentration after stimulation with acetylcholine by means of Fura-2 fluorescence captured with an inverted microscope. In our analysis we compared the features of Ca2+ signals in individual cells, synchronized activations, spatio-temporal grouping and the nature of intercellular communication between LECs. The latter was assessed by using the methodologies of the complex network theory. Our results point out that at the level of individual cells there are no significant differences when comparing the features of the signals with regard either to the type or the stage of the cataract. On the other hand, noticeable differences are observed at the multicellular level, despite inter-capsule variability. LCs associated with more developed cataracts were found to exhibit a slower collective response to stimulation, a less pronounced spatio-temporal clustering of LECs with similar signaling characteristics. The reconstructed intercellular networks were found to be sparser and more segregated than in LCs associated with mild cataracts. Moreover, we show that spontaneously active LECs often operate in localized groups with quite well aligned Ca2+ activity. The presence of spontaneous activity was also found to affect the stimulated Ca2+ responses of individual cells. Our findings indicate that the cataract progression entails the impairment of intercellular signaling thereby suggesting the functional importance of altered Ca2

  12. Mild hypothermia effects on intercellular adhesion molecule-1 and serum interleukin-6 expression in brain tissues of a rat focal ischemia model

    Institute of Scientific and Technical Information of China (English)

    Shengqi Fu; Lei Yang; Shuling Zhang; Shilong Sun; Xingai Mao

    2008-01-01

    BACKGROUND: Previous studies have confirmed the neuroprotective effect of mild hypothermia on ischemic brain injury.OBJECTIVE: To investigate the effects of mild hypothermia on intercellular adhesion molecule-1 expression and serum interleukin-6 levels in ischemic brain tissues of focal brain ischemia rats, and to explore the neuroprotective effects of mild hypothermia on ischemic brain injury.DESIGN, TIME AND SETTING: A randomized, controlled, neurobiological experiment was performed at the Central Laboratory, First Affiliated Hospital, Xinxiang Medical College, China from February to July 2006.MATERIALS: Thirty healthy, adult, Sprague Dawley rats were used to establish middle cerebral artery occlusion models using the suture method. The immunohistochemistry (streptavidin-biotin-peroxidase complex method) kit was purchased from Boster, China. Interleukin-6 radioimmunoassay was supplied by Institute of Radioimmunity, Technology Development Center, General Hospital of Chinese PLA. METHODS: The rats were equally and randomly assigned into mild hypothermia and control groups, and middle cerebral artery occlusion models were established. The rectal temperature was maintained at (37 ± 0.5)℃ in the control group. In the mild hypothermia group, the rectal temperature was maintained at (33±1)℃.MAIN OUTCOME MEASURES: At 12 hours after model establishment, the ischemic brain hemispheres were coronally sliced at the level of the optic chiasm. The number of intercellular adhesion molecule- 1 -positive vessels per high-power field was observed with an optical microscope. Serum interleukin-6 levels were measured by radioimmunoassay.RESULTS: Compared with the control group, intercellular adhesion molecule-I and serum interleukin-6 expressions were significantly decreased in ischemic brain tissues of the mild hypothermia group (P < 0.01).CONCLUSION: Mild hypothermia exhibits a neuroprotective effect by reducing serum interleukin-6 and intercellular adhesion molecule- 1

  13. THE EFFECT OF PENTACHLOROPHENOL ON DNA ADDUCT FORMATION IN C57B1/6 TRP53 +/+ AND C57B16 TRP53 -/- MICE EXPOSED TO BENZO[A]PYRENE MAY BE ASSOCIATED WITH P53 FUNCTION.

    Science.gov (United States)

    AbstractPrevious studies have shown that pentachlorophenol (PCP) has both potentiative and antagonistic effects on the genotoxicity of benzo[a]pyrene (B[a]P). It has been suggested that these effects are due to inhibition and/or induction of enzymes involved in the biotr...

  14. Activated endothelial interleukin-1beta, -6, and -8 concentrations and intercellular adhesion molecule-1 expression are attenuated by lidocaine.

    LENUS (Irish Health Repository)

    Lan, Wei

    2012-02-03

    Endothelial cells play a key role in ischemia reperfusion injury. We investigated the effects of lidocaine on activated human umbilical vein endothelial cell (HUVEC) interleukin (IL)-1beta, IL-6, and IL-8 concentrations and intercellular adhesion molecule-1 (ICAM-1) expression. HUVECs were pretreated with different concentrations of lidocaine (0 to 0.5 mg\\/mL) for 60 min, thereafter tumor necrosis factor-alpha was added at a concentration of 2.5 ng\\/mL and the cells incubated for 4 h. Supernatants were harvested, and cytokine concentrations were analyzed by enzyme-linked immunosorbent assay. Endothelial ICAM-1 expression was analyzed by using flow cytometry. Differences were assessed using analysis of variance and post hoc unpaired Student\\'s t-test where appropriate. Lidocaine (0.5 mg\\/mL) decreased IL-1beta (1.89 +\\/- 0.11 versus 4.16 +\\/- 1.27 pg\\/mL; P = 0.009), IL-6 (65.5 +\\/- 5.14 versus 162 +\\/- 11.5 pg\\/mL; P < 0.001), and IL-8 (3869 +\\/- 785 versus 14,961 +\\/- 406 pg\\/mL; P < 0.001) concentrations compared with the control. IL-1beta, IL-6, and IL-8 concentrations in HUVECs treated with clinically relevant plasma concentrations of lidocaine (0.005 mg\\/mL) were similar to control. ICAM-1 expression on lidocaine-treated (0.05 mg\\/mL) HUVECs was less than on controls (198 +\\/- 52.7 versus 298 +\\/- 50.3; Mean Channel Fluorescence; P < 0.001). Activated endothelial IL-1beta, IL-6, and IL-8 concentrations and ICAM-1 expression are attenuated only by lidocaine at concentrations larger than clinically relevant concentrations.

  15. A Mimic of the Tumor Microenvironment: A Simple Method for Generating Enriched Cell Populations and Investigating Intercellular Communication.

    Science.gov (United States)

    Domogauer, Jason D; de Toledo, Sonia M; Azzam, Edouard I

    2016-09-20

    Understanding the early heterotypic interactions between cancer cells and the surrounding non-cancerous stroma is important in elucidating the events leading to stromal activation and establishment of the tumor microenvironment (TME). Several in vitro and in vivo models of the TME have been developed; however, in general these models do not readily permit isolation of individual cell populations, under non-perturbing conditions, for further study. To circumvent this difficulty, we have employed an in vitro TME model using a cell growth substrate consisting of a permeable microporous membrane insert that permits simple generation of highly enriched cell populations grown intimately, yet separately, on either side of the insert's membrane for extended co-culture times. Through use of this model, we are capable of generating greatly enriched cancer-associated fibroblast (CAF) populations from normal diploid human fibroblasts following co-culture (120 hr) with highly metastatic human breast carcinoma cells, without the use of fluorescent tagging and/or cell sorting. Additionally, by modulating the pore-size of the insert, we can control for the mode of intercellular communication (e.g., gap-junction communication, secreted factors) between the two heterotypic cell populations, which permits investigation of the mechanisms underlying the development of the TME, including the role of gap-junction permeability. This model serves as a valuable tool in enhancing our understanding of the initial events leading to cancer-stroma initiation, the early evolution of the TME, and the modulating effect of the stroma on the responses of cancer cells to therapeutic agents.

  16. Altered Expression of Connexin-43 and Impaired Capacity of Gap Junctional Intercellular Communication in Prostate Cancer Cells

    Institute of Scientific and Technical Information of China (English)

    XING Yifei; XIAO Yajun; ZENG FuQing; ZHAO Jun; XIAO Chuanguo; XIONG Ping; FENG Wei

    2007-01-01

    Connexin-43 (Cx43) expression in prostate cancer (PCa) cells and the potency of gap junctional intercellular communication (GJIC) in the cells were investigated, with an attempt to elucidate the reason why the so-called "bystander effect" mediated by thymidine kinase (TK) suicide gene therapy on PCa cells is not of significance and to explore the role of GJIC in PCa carcinogenesis.mRNA and protein expression of Cx43 in a PCa cell line PC-3m was detected by reverse-transcription polymerase chain reaction (RT-PCR) and strapt-avidin-biotin-enzyme complex (SABC) immunohistochemical staining, and inherent GJIC of PC-3m cells was assayed by scrape-loading and dye transfer (SLDT) assay. The expression of Cx43 in human normal and malignant prostate tissues was determined by SABC immunohistochemistry as well. It was found that Cx43 mRNA and protein expression in PC-3m cells was slightly reduced as compared with positive controls and the location of Cx43 protein was aberrant in cytoplasm rather than on membrane. Assessment of paraffin sections demonstrated that the expression of Cx43 protein in PCa cells was abnormally located and markedly diminished as compared with normal prostatic epithelial ones, displaying a negative correlation to the pathological grade (χ2=4.025, P<0.05). Additionally, capacity of inherent GJIC in PC-3m cells was disrupted, which was semi-quantified as (+) or (-). It was indicated that both down-regulated expression of Cx43 mRNA and aberrant location of Cx43 protein participated in the mechanisms leading to deficient GJIC in PC-3m cells. Lack of efficient GJIC is a molecular event, which may contribute not only to limited extent of "bystander effect", but also to initiation and progression of prostatic neoplasm.

  17. Effects of H pylori infection on gap-junctional intercellular communication and proliferation of gastric epithelial cells in vitro

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To explore the effects of H pylori infection on gap-junctional intercellular communication (GJIC) and proliferation of gastric epithelial cells in vitro. METHODS: A human gastric epithelial cell line (SGC-7901) cultured on coverslips was exposed overnight to intact H pylori (CagA+ or CagA- strains) and sonicated extracts, respectively. GJIC between the cells was detected by fluorescence redistribution after photobleaching (FRAP) technique. Proliferation of SGC cells was determined by methylthiazolyl tetrazolium (MTT)assay.RESULTS: When compared with control in which cells were cultured with simple medium alone, both CagA+ and CagA- H pylori isolates could inhibit GJIC (CagA+:F = 57.98, P < 0.01; CagA-: F = 29.59, P < 0.01) and proliferation (CagA+: F = 42.65, P < 0.01; CagA-: F =58.14, P < 0.01) of SGC-7901 cells. Compared with CagA- strains, CagA+ H pylori more significantly downregulated GJIC of gastric cells (intact H pylori: t = 13.86,P < 0.01; sonicated extracts: t = 11.87, P < 0.01) and inhibited proliferation gastric cells to a lesser extent in vitro (intact H pylori: t = 3.06, P < 0.05; sonicated extracts: t = 3.94, P < 0.01).CONCLUSION: Compared with CagA- H pylori strains,CagA+ strains down-regulate GJIC of gastric epithelial cells more significantly and inhibit proliferation of gastric cells to a lesser extent in vitro. H pylori, especially CagA+ strains, may play an important role in gastric carcinogenesis.

  18. Antidiabetic Rosiglitazone Reduces Soluble Intercellular Adhesion Molecule-1 Level in Type 2 Diabetic Patients with Coronary Artery Disease

    Directory of Open Access Journals (Sweden)

    Guang Wang

    2008-01-01

    Full Text Available Background. We investigated the level of soluble adhesion molecules in diabetic patients and the effect of the peroxisome proliferator-activated receptor-γ (PPAR-γ agonist rosiglitazone on plasma levels of adhesion molecules and an inflammation marker in type 2 diabetic patients with coronary artery disease (CAD after percutaneous coronary intervention (PCI. Methods. A total of 116 diabetic patients with CAD who had undergone PCI were randomized to receive rosiglitazone (4 mg/d or not for 6 months. Plasma levels of soluble intercellular adhesion molecules (sICAM-1 and P-selectin (sP-selectin were measured on ELISA. Results. After 6-month rosiglitazone treatment, plasma levels of sICAM-1 were lower than baseline and control group levels (370.4 (332.4–421.9 pg/mL versus 423.5 (327.4–500.3 pg/mL and 404.6 (345.2–483.4 pg/mL, P<.001. In addition, plasma levels of C-reactive protein were significantly reduced from baseline levels. However, plasma level of sP-selectin was not significantly lowered with rosiglitazone treatment than with control treatment after 6-month follow-up. Conclusions. Rosiglitazone reduces chronic inflammatory responses and improves levels of markers of endothelial dysfunction in patients with diabetes and CAD. PPAR-γ agonist may have a beneficial effect on the vascular endothelium through its anti-inflammatory mechanism and may be useful as therapy in patients undergoing PCI.

  19. Purification and characterisation of an antifungal protein, MCha-Pr, from the intercellular fluid of bitter gourd (Momordica charantia) leaves.

    Science.gov (United States)

    Zhang, Beibei; Xie, Chengjian; Wei, Yunming; Li, Jing; Yang, Xingyong

    2015-03-01

    An antifungal protein, designated MCha-Pr, was isolated from the intercellular fluid of bitter gourd (Momordica charantia) leaves during a screen for potent antimicrobial proteins from plants. The isolation procedure involved a combination of extraction, ammonium sulphate precipitation, gel filtration on Bio-Gel P-6, ion exchange chromatography on CM-Sephadex, an additional gel filtration on HiLoad 16/60 Superdex 30, and finally, HPLC on a SOURCE 5RPC column. Matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry indicated that the protein had a molecular mass of 25733.46Da. Automated Edman degradation was used to determine the N-terminal sequence of MCha-Pr, and the amino acid sequence was identified as V-E-Y-T-I-T-G-N-A-G-N-T-P-G-G. The MCha-Pr protein has some similarity to the pathogenesis-related proteins from Atropa belladonna (deadly nightshade), Solanum tuberosum (potato), Ricinus communis (castor bean), and Nicotiana tabacum (tobacco). Analysis of the circular dichroism spectra indicated that MCha-Pr predominantly contains α-helix and β-sheet structures. MCha-Pr had inhibitory effects towards a variety of fungal species and the 50% inhibition of fungal growth (IC50) for Alternaria brassicae, Cercospora personata, Fusarium oxysporum, Mucor sp., and Rhizoctonia solani are 33 μM, 42 μM, 37 μM, 40 μM, and 48 μM, respectively. In addition, this antifungal protein can inhibit the germination of A. brassicae spores at 12.5 μM. These results suggest that MCha-Pr in bitter gourd leaves plays a protective role against phytopathogens and has a wide antimicrobial spectrum. PMID:25245535

  20. A Mimic of the Tumor Microenvironment: A Simple Method for Generating Enriched Cell Populations and Investigating Intercellular Communication.

    Science.gov (United States)

    Domogauer, Jason D; de Toledo, Sonia M; Azzam, Edouard I

    2016-01-01

    Understanding the early heterotypic interactions between cancer cells and the surrounding non-cancerous stroma is important in elucidating the events leading to stromal activation and establishment of the tumor microenvironment (TME). Several in vitro and in vivo models of the TME have been developed; however, in general these models do not readily permit isolation of individual cell populations, under non-perturbing conditions, for further study. To circumvent this difficulty, we have employed an in vitro TME model using a cell growth substrate consisting of a permeable microporous membrane insert that permits simple generation of highly enriched cell populations grown intimately, yet separately, on either side of the insert's membrane for extended co-culture times. Through use of this model, we are capable of generating greatly enriched cancer-associated fibroblast (CAF) populations from normal diploid human fibroblasts following co-culture (120 hr) with highly metastatic human breast carcinoma cells, without the use of fluorescent tagging and/or cell sorting. Additionally, by modulating the pore-size of the insert, we can control for the mode of intercellular communication (e.g., gap-junction communication, secreted factors) between the two heterotypic cell populations, which permits investigation of the mechanisms underlying the development of the TME, including the role of gap-junction permeability. This model serves as a valuable tool in enhancing our understanding of the initial events leading to cancer-stroma initiation, the early evolution of the TME, and the modulating effect of the stroma on the responses of cancer cells to therapeutic agents. PMID:27684198

  1. EXPRESSION OF INTERCELLULAR ADHESION MOLECULE IN LUNG TISSUES OF EXPERIMENTAL ACUTE LUNG INJURY AND THE AFFECT OF RHUBARB ON IT

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective. To approach the relation and the possible mechanism between the expression of intercellular adhesion molecule (ICAM-1) mRNA and acute lung injury (ALI) and the mechanisms of rhubarb in the prevention and treatment of the lung injury.Methods. Lipopolysaccharide (LPS) was injected into the sublingual vein of male Wistar rats to perform ALI animal model. The rats were divided into 4 groups: LPS group, control group, rhubarb group and dexamethasone group. Macroscopic and histopathological examinations were performed and biological markers were measured for the lung specimens. The markers included lung wet/dry weight, the rate of neutrophils and protein content in the pulmonary alveolar lavage fluid, pulmonary vascular permeability and pulmonary alveolar permeability index. Molecular hybridization method was used to determine the expression of ICAM-1 mRNA.Results. In the lung tissues, the ICAM-1 mRNA expression was increased in the endothelial cells of pulmonary veins and capillaries, rhubarb and dexamethasone had the action of decreasing the expression. The light reflex value in the gray scale scanning showed that in the comparison between the LPS and the control group, the gray scale value of the lung tissues in ALI was significantly increased, thus the light reflex value was markedly decreased (P<0.01), demonstrating the expression of ICAM-1 mRNA was increased. In comparison with the LPS group, dexamethasone and rhubarb could decrease the gray scale value of the lung tissue significantly, thus the light reflex value was elevated (P<0.01, P<0.05); the corresponding pathologic changes of lung tissues and the biological markers of the lung injury were significantly decreased or ameliorated.Conclusions. The increase of the expression of ICAM-1 mRNA in the lung tissues of ALI plays the roles in ALI. The application of rhubarb and dexamethasone can decrease the expression and ameliorate the lung damage; its mechanism is possibly via the inhibition of ICAM

  2. EXPRESSION OF INTERCELLULAR ADHESION MOLECULE IN LUNG TISSUES OF EXPERIMENTAL ACUTE LUNG INJURY AND THE AFFECT OF RHUBARB ON IT

    Institute of Scientific and Technical Information of China (English)

    李春盛; 桂培春; 何新华

    2000-01-01

    Objeaive. To approach the relation and the possible mechanism between the expression of intercellular adhesion molecule (ICAM-1) mRNA and acute lung injury (ALI) and the mechanisms of rhubarb in the prevention and treatment of the lung injury. Methods. Lipopolysaeeharide (LPS) was injected into the sublingual vein of male Wistar rats to perform ALI animal model. The rats were divided into 4 groups: LPS group, control group, rhubarb group and dexamethasoue group.Macroscopic and histopathological e~aminatiom were performed and biological markers were measured for the lung specimem. The markers included lung wet/dry weight, the rate of neutrophils and protein content in the pulmonary alveolar lavage fluid, pulmonary vascular permeability and pulmonary alveolar permeability index. Molecular hybridization method was used to determine the expression of ICAM-1 mRNA. Results. In the lung tissues, the ICAM-1 mRNA expression was increased in the endothelial cells of pulmonary veins and capillaries, rhubarb and dexamethasone had the action of decreasing the expression. The light reflex value in the gray scale scanning showed that in the comparison between the LPS and the control group, the gray scale value of the lung tissues in ALI was significantly increased, thus the light reflex value was markedly decreased (P < 0.01),demonstrating the expression of ICAM-1 mRNA was increased. In comparison with the LPS group, dexamethasoue and rhubarb emfld decrease the gray scale value of the lung tissue significantly, thus the light reflex value was elevated (P< 0.01, P < 0.05) ; the correslxmding pathologic changes of lung tissues and the biological markers of the lung injury were simifieantlv decreased or ameliorated. Conclusions. The increase of the expression d ICAM-1 mRNA in the lung tissues of ALI plays the roles in ALI.The application of rhubarb and dexamethasone can decrease the expression and ameliorate the lung damage; its mechanism is possibly via the inhibition of ICAM-1 m

  3. Phenotype characterization of embryoid body structures generated by a crystal comet effect tail in an intercellular cancer collision scenario

    International Nuclear Information System (INIS)

    Cancer is, by definition, the uncontrolled growth of autonomous cells that eventually destroy adjacent tissues and generate architectural disorder. However, this concept cannot be totally true. In three well documented studies, we have demonstrated that cancer tissues produce order zones that evolve over time and generate embryoid body structures in a space-time interval. The authors decided to revise the macroscopic and microscopic material in well-developed malignant tumors in which embryoid bodies were identified to determine the phenotype characterization that serves as a guideline for easy recognition. The factors responsible for this morphogenesis are physical, bioelectric, and magnetic susceptibilities produced by crystals that act as molecular designers for the topographic gradients that guide the surrounding silhouette and establish tissue head-tail positional identities. The structures are located in amniotic-like cavities and show characteristic somite-like embryologic segmentation. Immunophenotypic study has demonstrated exclusion factor positional identity in relation to enolase-immunopositive expression of embryoid body and human chorionic gonadotropin immunopositivity exclusion factor expression in the surrounding tissues. The significance of these observations is that they can also be predicted by experimental image data collected by the Large Hadron Collider (LHC) accelerator at the European Organization for Nuclear Research, in which two-beam subatomic collision particles in the resulting debris show hyperorder domains similar to those identified by us in intercellular cancer collisions. Our findings suggest that we are dealing with true reverse biologic system information in an activated collective cancer stem cell memory, in which physics participates in the elaboration of geometric complexes and chiral biomolecules that serve to build bodies with embryoid print as it develops during gestation. Reversal mechanisms in biology are intimately

  4. Base substitution mutations induced by metabolically activated aflatoxin B1.

    OpenAIRE

    Foster, P. L.; Eisenstadt, E; Miller, J H

    1983-01-01

    We have determined the base substitutions generated by metabolically activated aflatoxin B1 in the lacI gene of a uvrB- strain of Escherichia coli. By monitoring over 70 different nonsense mutation sites, we show that activated aflatoxin B1 specifically induced GxC leads to TxA transversions. One possible pathway leading to this base change involves depurination at guanine residues. We consider this mechanism of mutagenesis in the light of our other findings that the carcinogens benzo[a]pyren...

  5. Pulmonary gene and microRNA expression changes in mice exposed to benzo(a)pyrene by oral gavage

    International Nuclear Information System (INIS)

    Highlights: → The study examines pulmonary response in mice exposed to BaP by oral gavage. → We examined pulmonary gene and miRNA expression changes and measured DNA adducts. → We compare the mechanisms of action that operate in lungs relative to the liver. → We show differences in biological pathways activated in lungs versus the liver. → We suggest that liver miRNAs are less sensitive to perturbations than lung miRNAs. -- Abstract: Exposure to the environmental mutagen benzo(a)pyrene (BaP) alters the expression of AHR-responsive genes as well as genes involved in other pathways. We recently reported that exposure of adult mice to BaP resulted in a robust transcriptome response in the liver, but this was accompanied by a complete lack of change in microRNA (miRNA) expression. Since BaP exposure does not result in hepatocarcinogenicity, but does cause lung cancer, in the present study we examine the pulmonary mRNA and miRNA responses to BaP in the same mice. Adult male B6C3F1 mice were exposed to 150 and 300 mg/kg BaP by oral gavage for three consecutive days and sacrificed 4 h after the last exposure. Serum clinical chemistry was performed for both the doses to assess the general toxicity of BaP; a modest decrease in serum inorganic phosphorous was observed at both the doses. A small decrease in serum glucose following 150 mg/kg and alkaline phosphatase following 300 mg/kg BaP was observed. BaP-DNA adduct levels in whole lung and liver tissues were assessed by 32P postlabelling and similar dose dependent increases were observed for lung and liver. Using DNA microarrays, pulmonary mRNA and miRNA expressions were analysed. Over 1000 genes were statistically differentially expressed (p < 0.05). The perturbed pathways included oxidative stress, xenobiotic metabolism, cell proliferation, cell cycle, B and T-cell receptor signalling and primary immunodeficiency signalling pathways. Analysis of miRNA profiles revealed downregulation of miR-150, miR-142-5p, mi

  6. Phosphatase activity in commercial spleen exonuclease decreases the recovery of benzo[a]pyrene and N-hydroxy-2-naphthylamine DNA adducts by 32P-postlabeling.

    Science.gov (United States)

    Adams, S P; Laws, G M; Selden, J R; Nichols, W W

    1994-05-15

    Spleen exonuclease, which degrades nucleic acids into single 3'-nucleotides, is used in the detection of DNA adducts by 32P-postlabeling. Contamination of the exonuclease with phosphatase activity can reduce the recovery of benzo[a]pyrene and N-hydroxy-2-naphthylamine DNA adducts by 32P-postlabeling. Four preparations of spleen exonuclease containing varying levels of phosphatase activity (2-naphthylamine DNA adducts. Surprisingly, recovery of these DNA adducts was nearly 10 times greater using nuclease P1 than when using 1-butanol extraction for adduct enrichment, since arylamine DNA adducts have previously been reported to be poorly detected by 32P-postlabeling after nuclease P1 treatment. Our data indicate that the hydrolysis of DNA by spleen exonuclease may be an important source of variability in both qualitative and quantitative analysis of adducts by 32P-postlabeling. PMID:8059938

  7. Phenotype characterization of embryoid body structures generated by a crystal comet effect tail in an intercellular cancer collision scenario

    Directory of Open Access Journals (Sweden)

    Diaz JA

    2012-01-01

    Full Text Available Jairo A Diaz, Mauricio F MurilloDepartment of Pathology, Hospital Departmental Villavicencio, Hospital Departmental Granada, Medicine School, University Cooperative of Colombia, Villavicencio, Meta, ColombiaAbstract: Cancer is, by definition, the uncontrolled growth of autonomous cells that eventually destroy adjacent tissues and generate architectural disorder. However, this concept cannot be totally true. In three well documented studies, we have demonstrated that cancer tissues produce order zones that evolve over time and generate embryoid body structures in a space-time interval. The authors decided to revise the macroscopic and microscopic material in well-developed malignant tumors in which embryoid bodies were identified to determine the phenotype characterization that serves as a guideline for easy recognition. The factors responsible for this morphogenesis are physical, bioelectric, and magnetic susceptibilities produced by crystals that act as molecular designers for the topographic gradients that guide the surrounding silhouette and establish tissue head-tail positional identities. The structures are located in amniotic-like cavities and show characteristic somite-like embryologic segmentation. Immunophenotypic study has demonstrated exclusion factor positional identity in relation to enolase-immunopositive expression of embryoid body and human chorionic gonadotropin immunopositivity exclusion factor expression in the surrounding tissues. The significance of these observations is that they can also be predicted by experimental image data collected by the Large Hadron Collider (LHC accelerator at the European Organization for Nuclear Research, in which two-beam subatomic collision particles in the resulting debris show hyperorder domains similar to those identified by us in intercellular cancer collisions. Our findings suggest that we are dealing with true reverse biologic system information in an activated collective cancer stem cell

  8. Mononuclear phagocyte intercellular crosstalk facilitates transmission of cell-targeted nanoformulated antiretroviral drugs to human brain endothelial cells

    Directory of Open Access Journals (Sweden)

    Kanmogne GD

    2012-05-01

    Full Text Available Georgette D Kanmogne1, Sangya Singh1, Upal Roy1, Xinming Liu1, JoEllyn McMillan1, Santhi Gorantla1, Shantanu Balkundi1, Nathan Smith1, Yazen Alnouti2, Nagsen Gautam2, You Zhou3, Larisa Poluektova1, Alexander Kabanov2, Tatiana Bronich2, Howard E Gendelman11Departments of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, 2Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE; 3Center for Biotechnology, University of Nebraska-Lincoln, Lincoln, NE, USAAbstract: Despite the successes of antiretroviral therapy (ART, HIV-associated neurocognitive disorders remain prevalent in infected people. This is due, in part, to incomplete ART penetration across the blood–brain barrier (BBB and lymph nodes and to the establishment of viral sanctuaries within the central nervous system. In efforts to improve ART delivery, our laboratories developed a macrophage-carriage system for nanoformulated crystalline ART (nanoART (atazanavir, ritonavir, indinavir, and efavirenz. We demonstrate that nanoART transfer from mononuclear phagocytes (MP to human brain microvascular endothelial cells (HBMEC can be realized through cell-to-cell contacts, which can facilitate drug passage across the BBB. Coculturing of donor MP containing nanoART with recipient HBMEC facilitates intercellular particle transfer. NanoART uptake was observed in up to 52% of HBMEC with limited cytotoxicity. Folate coating of nanoART increased MP to HBMEC particle transfer by up to 77%. To translate the cell assays into relevant animal models of disease, ritonavir and atazanavir nanoformulations were injected into HIV-1-infected NOD/scid-γcnull mice reconstituted with human peripheral blood lymphocytes. Atazanavir and ritonavir levels in brains of mice treated with folate-coated nanoART were three- to four-fold higher than in mice treated with noncoated particles. This was associated with decreased viral load in the spleen and

  9. Polymorphism K469E of intercellular adhesion molecule-1 gene and restenosis after coronary stenting in Chinese patients

    Institute of Scientific and Technical Information of China (English)

    刘兆平; 霍勇; 李建平; 张岩; 薛琳; 赵春玉; 洪秀梅; 黄爱群; 高炜

    2004-01-01

    Background Inflammation is a major cause of restenosis after coronary stenting. Intercellular adhesion molecule-1 ( ICAM-1 ) is an important adhesion molecule that plays a key role in the tight adhesion between leukocytes and vascular endothelium. The object of this study was to investigate the association between the K469E polymorphism of the ICAM-1 gene and restenosis after coronary stenting in North Chinese population.Methods The ICAM-1 K469E polymorphism was genotyped using polymerase chain reaction- restriction fragment length polymorphism method in 124 patients who had undergone coronary stenting and coronary angiography at least 3 months earlier. Information on clinical risk factors and procedure- related data were also collected. Results Of 124 enrolled patients in total, there were 72 cases of in-stent restenosis. The restenosis rate in this population was 58. 1%. The frequencies of the three possible genotypes of the ICAM-1 K469E polymorphism were: KK genotype 50.8%, EE genotype 41.9%, and EK genotype 41.9%.Among restenosis patients, the frequency of the KK genotype was 58. 3% and the frequency of E allele carriers was 41.7%. Among non-restenosis patients, the frequency of the KK genotype was 40.4%, and the frequency of E allele carriers was 59. 6%. The distribution of these two genotype groups between restenosis and non-restenosis patients was significantly different (P=0.049). Using multivariate logistic regression, the difference between the two groups was more apparent. The odds ratio of KK homozygotes vs E allele carriers was 2.6, with 95% confidence interval 1.2 -5.8 (P =0. 018). After grading of risk factors, we found that the KK genotype was a stronger predictor of in- stent restenosis in obesity or hyperlipemia patients, with an odds ratio of 9.3 and 3.7, respectively (P<0.05).Conclusion In our study population, KK homozygotes of the ICAM-1 codon 469 mutation had a higher risk of restenosis after coronary stenting, especially in the case of obese

  10. Serum inter-cellular adhesion molecule 1 is an early marker of diagnosis and prediction of severe acute pancreatitis

    Institute of Scientific and Technical Information of China (English)

    Hai-Hang Zhu; Lin-Lin Jiang

    2012-01-01

    AIM:To determine if serum inter-cellular adhesion molecule 1 (ICAM-1) is an early marker of the diagnosis and prediction of severe acute pancreatitis (SAP)within 24 h of onset of pain,and to compare the sensitivity,specificity and prognostic value of this test with those of acute physiology and chronic health evaluation (APACHE) Ⅱ score and interleukin-6 (IL-6).METHODS:Patients with acute pancreatitis (AP) were divided into two groups according to the Ranson's criteria:mild acute pancreatitis (MAP) group and SAP group.Serum ICAM-1,APACHE Ⅱ and IL-6 levels were detected in all the patients.The sensitivity,specificity and prognostic value of the ICAM-1,APACHE Ⅱ score and IL-6 were evaluated.RESULTS:The ICAM-1 level in 36 patients with SAP within 24 h of onset of pain was increased and was significantly higher than that in the 50 patients with MAP and the 15 healthy volunteers (P < 0.01).The ICAM-1 level (25 ng/mL) was chosen as the optimum cutoff to distinguish SAP from MAP,and the sensitivity,specificity,positive predictive value,negative predictive value (NPV),positive likelihood ratio and negative likelihood ratio were 61.11%,71.42%,0.6111,0.7142,2.1382 and 0.5445,respectively.The area under the curve demonstrated that the prognostic accuracy of ICAM-1 (0.712) was similar to the APACHE-Ⅱ scoring system (0.770) and superior to IL-6 (0.508) in distinguishing SAP from MAP.CONCLUSION:ICAM-1 test is a simple,rapid and reliable method in clinical practice.It is an early marker of diagnosis and prediction of SAP within the first 24 h after onset of pain or on admission.As it has a relatively low NPV and does not allow it to be a stand-alone test for the diagnosis of AP,other conventional diagnostic tests are required.

  11. CXC chemokine ligand 12/Stromal cell-derived factor-1 regulates cell adhesion in human colon cancer cells by induction of intercellular adhesion molecule-1

    OpenAIRE

    Tung Shui-Yi; Chang Shun-Fu; Chou Ming-Hui; Huang Wen-Shih; Hsieh Yung-Yu; Shen Chien-Heng; Kuo Hsing-Chun; Chen Cheng-Nan

    2012-01-01

    Abstract Background The CXC chemokine ligand 12 (CXCL12)/stromal cell-derived factor-1 (SDF-1) and CXC receptor 4 (CXCR4) axis is involved in human colorectal cancer (CRC) carcinogenesis and can promote the progression of CRC. Interaction between CRC cells and endothelium is a key event in tumor progression. The aim of this study was to investigate the effect of SDF-1 on the adhesion of CRC cells. Methods Human CRC DLD-1 cells were used to study the effect of SDF-1 on intercellular adhesion m...

  12. Fructose Induces the Inflammatory Molecule ICAM-1 in Endothelial Cells

    OpenAIRE

    Glushakova, Olena; Kosugi, Tomoki; Roncal, Carlos; Mu, Wei; Heinig, Marcelo; Cirillo, Pietro; Sánchez-Lozada, Laura G.; Richard J Johnson; Nakagawa, Takahiko

    2008-01-01

    Epidemiologic studies have linked fructose intake with the metabolic syndrome, and it was recently reported that fructose induces an inflammatory response in the rat kidney. Here, we examined whether fructose directly stimulates endothelial inflammatory processes by upregulating the inflammatory molecule intercellular adhesion molecule-1 (ICAM-1). When human aortic endothelial cells were stimulated with physiologic concentrations of fructose, ICAM-1 mRNA and protein expression increased in a ...

  13. 氧化应激对大肠癌细胞迁移、血管内皮生长因子表达及细胞间通信的影响%Effect of Oxidative Stress Cell Migration,Vascular Epithelial Growth Factor Expression and Gap Junction Intercellular Communication on Colon Cancer

    Institute of Scientific and Technical Information of China (English)

    刘培根; 马利林; 朱建伟

    2011-01-01

    Objective To investigate the effects of oxidative stress on colon cancer cell migration, vascular epithelial growth factor expression and gap junction intercellular communication. Methods We stimulated HCT-8 human colon cancer cell with different concentration of hydrogen peroxide, through which mimicking the oxygen stress environment in the colon lumen was devedoped. We observed the colon cancer cell migration using Transwell Chamber assay, the expression of VEGF gene using immunocytochemistry, the gap junction intercellular communication using the scrape loading/dye transfer technique,and furthermore the expression of intercellular communication protein Connexin 43 using Western blot.Results The oxygen stress environment induced by hydrogen peroxide at concentration ≤ 10-5 mol/L shightly promoted and concentration of 10-5 mol/L significantly promoted the colon cancer migration (t =2.247, P<0.05), up-regulated the expression of VEGF gene (Z= 3.938, P= 0.000) and inhibited the intercellular communication (Z= 3.938, P = 0.000). Conclusion Oxidative stress mimicked by hydrogen peroxide might be involved in colorectal tumor development through promotion of the colon cancer cell migration, up-regulation of VEGF gene and inhibition of the intercellular communication.%目的 探讨氧化应激对大肠癌细胞迁移能力、血管内皮细胞生长因子表达及细胞间通信的影响.方法 使用H2O2模拟大肠腔内氧化应激环境,通过不同浓度H2O2刺激人结肠癌细胞HCT-8,使癌细胞处于氧化应激状态,通过Transwell小室观察大肠癌细胞迁移能力;利用免疫细胞化学观察VEGF表达;利用划痕染料传输试验LY/DT法测定细胞间通信连接,最后利用Western blot进一步检测细胞间通信连接蛋白(Connexin 43)的表达.结果 当H2O2浓度≤10-5mol/L时,不同程度地促进细胞的迁移,上调结肠癌细胞HCT-8 VEGF的表达,抑制细胞问通信;当H2O2浓度为10-5mol/L时,明显促进细胞的迁移(t=2

  14. Beta-sitosterol from psyllium seed husk (Plantago ovata Forsk) restores gap junctional intercellular communication in Ha-ras transfected rat liver cells.

    Science.gov (United States)

    Nakamura, Yasushi; Yoshikawa, Noriko; Hiroki, Ikumi; Sato, Kenji; Ohtsuki, Kozo; Chang, Chia-Cheng; Upham, Brad L; Trosko, James E

    2005-01-01

    We purified compounds from the husks of psyllium seeds (Plantago ovata Forsk; desert Indian wheat), beginning with an ethanol extraction then followed by HP-20 and silica gel chromatography, which restored gap junctional intercellular communication (GJIC) in v-Ha-ras transfected rat liver epithelial WB-F344 cell line (WB-Ha-ras). GJIC was assessed by a scrape loading dye transfer assay. The active compound was identified as beta-sitosterol based on gas chromatography retention times and electron ionization mass spectroscopy (EI-MS) spectrum of authentic beta-sitosterol. Authentic beta-sitosterol restored GJIC in the tumorigenic WB-Ha-ras GJIC-deficient cells at a dose of 2.4 microM. In addition, a similar phytosterol, stigmasterol, also restored GJIC, albeit at a lower activity. beta-sitosterol and stigmasterol increased the level of connexin43 protein (Cx43) and restored phosphorylation of Cx43 to levels similar to the parental nontransfected cell line. We concluded that the restoration of intercellular communication in the GJIC-deficient, tumorigenic WB-Ha-ras cell line by the ethanol soluble fraction of psyllium seed husks is largely due to the presence of the phytosterol, beta-sitosterol. We discuss implications for dietary modulation of cancer by beta-sitosterol. PMID:15860444

  15. Cell adhesion molecules involved in the leukocyte recruitment induced by venom of the snake Bothrops jararaca

    OpenAIRE

    Catarina F. P. Teixeira; Stella R. Zamuner

    2002-01-01

    It has been shown that Bothrops jararaca venom (BjV) induces a significant leukocyte accumulation, mainly neutrophils, at the local of tissue damage. Therefore, the role of the adhesion molecules intercellular adhesion molecule-1 (ICAM-1), LECAM-1, CD18, leukocyte function-associated antigen-1 (LFA-1) and platelet endothelial cell adhesion molecule-1 (PECAM-1) on the BjV-induced neutrophil accumulation and the correlation with release of LTB4, TXA2, tumor necrosis factor-alpha, interleukin (I...

  16. Polycyclic aromatic hydrocarbons as skin carcinogens: Comparison of benzo[a]pyrene, dibenzo[def,p]chrysene and three environmental mixtures in the FVB/N mouse

    Energy Technology Data Exchange (ETDEWEB)

    Siddens, Lisbeth K.; Larkin, Andrew [Department of Environmental and Molecular Toxicology, Oregon State University (United States); Superfund Research Center, Oregon State University (United States); Krueger, Sharon K. [Superfund Research Center, Oregon State University (United States); The Linus Pauling Institute, Oregon State University (United States); Bradfield, Christopher A. [McArdle Laboratory for Cancer Research, University of Wisconsin, Madison, WI 53706 (United States); Waters, Katrina M.; Tilton, Susan C. [Superfund Research Center, Oregon State University (United States); Computational Biology and Bioinformatics Group, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Pereira, Cliff B. [Superfund Research Center, Oregon State University (United States); Deptartment of Statistics, Oregon State University, Corvallis, OR 97331 (United States); Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); Löhr, Christiane V. [Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331 (United States); Arlt, Volker M.; Phillips, David H. [Analytical and Environmental Sciences Division, MRC-HPA Centre for Environment and Health, King' s College London, London SE1 9NH (United Kingdom); Williams, David E., E-mail: david.williams@oregonstate.edu [Department of Environmental and Molecular Toxicology, Oregon State University (United States); Superfund Research Center, Oregon State University (United States); The Linus Pauling Institute, Oregon State University (United States); Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); and others

    2012-11-01

    The polycyclic aromatic hydrocarbon (PAH), benzo[a]pyrene (BaP), was compared to dibenzo[def,p]chrysene (DBC) and combinations of three environmental PAH mixtures (coal tar, diesel particulate and cigarette smoke condensate) using a two stage, FVB/N mouse skin tumor model. DBC (4 nmol) was most potent, reaching 100% tumor incidence with a shorter latency to tumor formation, less than 20 weeks of 12-O-tetradecanoylphorbol-13-acetate (TPA) promotion compared to all other treatments. Multiplicity was 4 times greater than BaP (400 nmol). Both PAHs produced primarily papillomas followed by squamous cell carcinoma and carcinoma in situ. Diesel particulate extract (1 mg SRM 1650b; mix 1) did not differ from toluene controls and failed to elicit a carcinogenic response. Addition of coal tar extract (1 mg SRM 1597a; mix 2) produced a response similar to BaP. Further addition of 2 mg of cigarette smoke condensate (mix 3) did not alter the response with mix 2. PAH-DNA adducts measured in epidermis 12 h post initiation and analyzed by {sup 32}P post‐labeling, did not correlate with tumor incidence. PAH‐dependent alteration in transcriptome of skin 12 h post initiation was assessed by microarray. Principal component analysis (sum of all treatments) of the 922 significantly altered genes (p < 0.05), showed DBC and BaP to cluster distinct from PAH mixtures and each other. BaP and mixtures up-regulated phase 1 and phase 2 metabolizing enzymes while DBC did not. The carcinogenicity with DBC and two of the mixtures was much greater than would be predicted based on published Relative Potency Factors (RPFs). -- Highlights: ► Dibenzo[def,p]chrysene (DBC), 3 PAH mixtures, benzo[a]pyrene (BaP) were compared. ► DBC and 2 PAH mixtures were more potent than Relative Potency Factor estimates. ► Transcriptome profiles 12 hours post initiation were analyzed by microarray. ► Principle components analysis of alterations revealed treatment-based clustering. ► DBC gave a unique

  17. Acquired Tumor Cell Radiation Resistance at the Treatment Site Is Mediated Through Radiation-Orchestrated Intercellular Communication

    Energy Technology Data Exchange (ETDEWEB)

    Aravindan, Natarajan, E-mail: naravind@ouhsc.edu [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (United States); Aravindan, Sheeja; Pandian, Vijayabaskar; Khan, Faizan H.; Ramraj, Satish Kumar; Natt, Praveen [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (United States); Natarajan, Mohan [Department of Pathology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas (United States)

    2014-03-01

    Purpose: Radiation resistance induced in cancer cells that survive after radiation therapy (RT) could be associated with increased radiation protection, limiting the therapeutic benefit of radiation. Herein we investigated the sequential mechanistic molecular orchestration involved in radiation-induced radiation protection in tumor cells. Results: Radiation, both in the low-dose irradiation (LDIR) range (10, 50, or 100 cGy) or at a higher, challenge dose IR (CDIR), 4 Gy, induced dose-dependent and sustained NFκB-DNA binding activity. However, a robust and consistent increase was seen in CDIR-induced NFκB activity, decreased DNA fragmentation, apoptosis, and cytotoxicity and attenuation of CDIR-inhibited clonal expansion when the cells were primed with LDIR prior to challenge dose. Furthermore, NFκB manipulation studies with small interfering RNA (siRNA) silencing or p50/p65 overexpression unveiled the influence of LDIR-activated NFκB in regulating CDIR-induced DNA fragmentation and apoptosis. LDIR significantly increased the transactivation/translation of the radiation-responsive factors tumor necrosis factor-α (TNF-α), interleukin-1α (IL-1α), cMYC, and SOD2. Coculture experiments exhibit LDIR-influenced radiation protection and increases in cellular expression, secretion, and activation of radiation-responsive molecules in bystander cells. Individual gene-silencing approach with siRNAs coupled with coculture studies showed the influence of LDIR-modulated TNF-α, IL-1α, cMYC, and SOD2 in induced radiation protection in bystander cells. NFκB inhibition/overexpression studies coupled with coculture experiments demonstrated that TNF-α, IL-1α, cMYC, and SOD2 are selectively regulated by LDIR-induced NFκB. Conclusions: Together, these data strongly suggest that scattered LDIR-induced NFκB-dependent TNF-α, IL-1α, cMYC, and SOD2 mediate radiation protection to the subsequent challenge dose in tumor cells.

  18. Acquired Tumor Cell Radiation Resistance at the Treatment Site Is Mediated Through Radiation-Orchestrated Intercellular Communication

    International Nuclear Information System (INIS)

    Purpose: Radiation resistance induced in cancer cells that survive after radiation therapy (RT) could be associated with increased radiation protection, limiting the therapeutic benefit of radiation. Herein we investigated the sequential mechanistic molecular orchestration involved in radiation-induced radiation protection in tumor cells. Results: Radiation, both in the low-dose irradiation (LDIR) range (10, 50, or 100 cGy) or at a higher, challenge dose IR (CDIR), 4 Gy, induced dose-dependent and sustained NFκB-DNA binding activity. However, a robust and consistent increase was seen in CDIR-induced NFκB activity, decreased DNA fragmentation, apoptosis, and cytotoxicity and attenuation of CDIR-inhibited clonal expansion when the cells were primed with LDIR prior to challenge dose. Furthermore, NFκB manipulation studies with small interfering RNA (siRNA) silencing or p50/p65 overexpression unveiled the influence of LDIR-activated NFκB in regulating CDIR-induced DNA fragmentation and apoptosis. LDIR significantly increased the transactivation/translation of the radiation-responsive factors tumor necrosis factor-α (TNF-α), interleukin-1α (IL-1α), cMYC, and SOD2. Coculture experiments exhibit LDIR-influenced radiation protection and increases in cellular expression, secretion, and activation of radiation-responsive molecules in bystander cells. Individual gene-silencing approach with siRNAs coupled with coculture studies showed the influence of LDIR-modulated TNF-α, IL-1α, cMYC, and SOD2 in induced radiation protection in bystander cells. NFκB inhibition/overexpression studies coupled with coculture experiments demonstrated that TNF-α, IL-1α, cMYC, and SOD2 are selectively regulated by LDIR-induced NFκB. Conclusions: Together, these data strongly suggest that scattered LDIR-induced NFκB-dependent TNF-α, IL-1α, cMYC, and SOD2 mediate radiation protection to the subsequent challenge dose in tumor cells

  19. Lauric acid abolishes interferon-gamma (IFN-γ)-induction ofIntercellular AdhesionMolecule-1 (ICAM-1) andVascularCellAdhesionMolecule-1 (VCAM-1) expression in human macrophages

    Institute of Scientific and Technical Information of China (English)

    Wei-Siong Lim; Mary-Shi-Ying Gan; Melissa-Hui-Ling Ong; Choy-Hoong Chew

    2015-01-01

    Objective:To investigate the effect of different concentrations of lauric acid on Intercellular Adhesion Molecule-1 (ICAM-1) and Vascular Cell Adhesion Molecule-1 (VCAM-1) expression in IFN-γ stimulated human monocytic THP-1 cell line.Methods:THP-1 cell were cultured using Roswell Park Memorial Institute medium supplemented with 10% fetal bovine serum. THP-1 monocytes were firstly differentiated into macrophages by using phorbol-12-myristate-13-acetate. IFN-γ response test was perfomed and total cellular RNA was extracted using TRI Reagent®LS before q-RT-PCR was carried out. Subsequently, IFN-γ treated THP-1 macrophages were stimulated with increasing doses of lauric acid for another 24 hour, before q-RT-PCR. MTT assay was carried out to investigate the effect of lauric acid on undifferentiated and differentiated THP-1 cells.Results:The mRNA expression levels of ICAM-1 and VCAM-1 were normalized toβ-actin and relatived to the untreated cells. The expressions of ICAM-1 and VCAM-1 were significantly induced in cells treated with 10 ng/mL of IFN-γ. This showed that IFN-γ could up-regulate inflammatory process and may cause atheroma formation. Although lauric acid did not have any significant impact on undifferentiated and differentiated THP-1 cell viability, the normalized fold expressions of ICAM-1 and VCAM-1 in IFN-γ-treated THP-1 macrophages were decreased significantly in a dose dependent manner with the presence of increasing doses of lauric acid.Conclusions:This study successfully proved that lauric acid was able to antagonize the up-regulatory effect of IFN-γ on ICAM-1 and VCAM-1 expressions in THP-1 macrophages. This indicates that lauric acid may be an anti-inflammatory therapeutic and prophylaxis agent for atherosclerosis.

  20. 溶剂效应对脱除煤沥青中3,4-苯并芘的影响%Solvent effect on removal of benzo[a]pyrene in coal tar pitch

    Institute of Scientific and Technical Information of China (English)

    孙昱; 廖志远; 苏龙; 曾鹏

    2014-01-01

    研究了单种溶剂、混合溶剂对3,4-苯并芘的溶解选择性及煤沥青溶解量。并以顺丁烯二酸酐为改性剂、硫酸为催化剂,考察了溶剂效应对降低煤沥青中3,4-苯并芘的影响。研究表明,环己烷、甲苯,环己烷、乙酸丁酯组成的混合溶剂具有较好的3,4-苯并芘溶解选择性和合适的煤沥青溶解量。当环己烷∶甲苯=2∶1(体积比)和环己烷∶乙酸丁酯=2∶1(体积比)为反应溶剂时,能够高效地脱除煤沥青中3,4-苯并芘,煤沥青中3,4-苯并芘降低率分别达到88.26%和90.83%。其原因认为是此类溶剂能使包裹在沥青颗粒内部的3,4-苯并芘释放出来,且3,4-苯并芘与改性剂能够形成均相反应体系,大部分不具有致癌性的高相对分子质量环芳烃与改性剂之间形成两相体系,从而提高了改性剂与3,4-苯并芘的有效反应。%The solubility selectivity for benzo[a]pyrene and dissolved amount for coal tar pitch of single solvent,mixed solvents were studied. Using maleic anhydride as modifying agent and sulfuric acid as catalyst,the solvent effect on reducing the concentration of benzo[a]pyrene in coal tar pitch was investigated. The mixed solvents,cyclohexane and toluene,cyclohexane and butyl acetate had appropriate benzo[a]pyrene solubility selectivity and coal tar pitch solubility. When using cyclohexane∶toluene=2∶1(v/v),cyclohexane∶butyl acetate=2∶1(v/v)as reaction solvent, benzo[a]pyrene in coal tar pitch could be removed efficiently,with decreases of 88.26%and 90.83%for benzo[a]pyrene in coal tar pitch respectively. Using these kinds of solvent,benzo[a]pyrene wrapped in coal tar pitch could be released. In addition,a homogeneous system between modifying agent and benzo[a]pyrene was formed,with most non-carcinogenic high molecular weight PAHs and modifying agent forming a two phase system. As a result,the effective reaction between modifying agent and benzo[a]pyrene was greatly

  1. Alterations in benzo(A)pyrene metabolism and in vivo binding to hepatic DNA in rats red diets containing menhaden oil

    Energy Technology Data Exchange (ETDEWEB)

    Wade, A.E.; Dharwadkar, S.

    1987-01-01

    Polyunsaturated fatty acids of the omega-6 type have been shown to support the mixed function oxidases (MFO) responsible for carcinogen activation and to promote tumorigenesis in laboratory animals. The omega-3 fatty acids contained in menhaden oil (MO) have been shown to enhance MFO activity and increase the binding of Benzo(a)pyrene (B(a)P) metabolites to calf thymus DNA in an in vitro microsomal system. Rats fed two levels of MO (0.5% and 20%) for 11 days received a single i.p. dose of (/sup 3/H)B(a)P (5 m Ci/kg) dissolved in DMSO. At selected time intervals thereafter rats were killed, blood withdrawn, livers removed and DNA extracted. Hepatic microsomes were recovered from control rats on each diet at the time of B(a)P administration to assess MFO activities. Binding of B(a)P to DNA was higher in rats fed the 20% MO diet suggesting an increased rate of B(a)P activation. Blood levels of B(a)P were elevated at 16 and 24 hours post B(a)P, however no differences in urine concentrations were observed. Elevations in concentration of cytochrome P-450, ethoxycoumarin dealkylase, and glutathione S-transferase suggest that omega-3 fatty acids of menhaden fish oil support MFO related reactions not unlike the omega-6 fatty acids.

  2. In vitro and in vivo percutaneous absorption of benzo[a]pyrene from petroleum crude-fortified soil in the rat

    International Nuclear Information System (INIS)

    Concern regarding dermal exposure to soils contaminated with potentially toxic materials such as dioxins, pesticides, heavy metals, polynuclear aromatics (PNA) and petroleum products containing PNA, has prompted government and private sectors to examine and formulate dermal risk assessment methodologies for contaminated soils. In the absence of experimentally determined percutaneous absorption values, many risk assessment schemes substitute available animal toxicology data on the pure contaminant, estimate dermal penetration of pure contaminant based on physicochemical models or, in the extreme, assume 100% bioavailability of the contaminant from soil. Risk assessment based on these approaches is likely to result in an overestimate of dermal bioavailability of contaminants from soil, particularly for the water insoluble lipophilic compounds found in petroleum products. The authors have performed dermal bioavailability studies on a variety of lipophilic materials and special emphasis has been placed on the development and implementation of a modified in vitro technique for evaluating the percutaneous absorption of PNA and PNA mixtures. In the present paper, they apply the modified in vitro technique to evaluate the percutaneous absorption of [3H-labelled] benzo[a]pyrene (BaP) in petroleum crude oil sorbed on soil and compare the results with those for the percutaneous absorption of BaP from crude oil alone. Results of the in vitro experiments are compared with findings from parallel in vivo experiments

  3. Inhibition of HIV-1 reverse transcriptase-catalyzed synthesis by intercalated DNA Benzo[a]Pyrene 7,8-Dihydrodiol-9,10-Epoxide adducts.

    Directory of Open Access Journals (Sweden)

    Parvathi Chary

    Full Text Available To aid in the characterization of the relationship of structure and function for human immunodeficiency virus type-1 reverse transcriptase (HIV-1 RT, this investigation utilized DNAs containing benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE-modified primers and templates as a probe of the architecture of this complex. BPDE lesions that differed in their stereochemistry around the C10 position were covalently linked to N (6-adenine and positioned in either the primer or template strand of a duplex template-primer. HIV-1 RT exhibited a stereoisomer-specific and strand-specific difference in replication when the BPDE-lesion was placed in the template versus the primer strand. When the C10 R-BPDE adduct was positioned in the primer strand in duplex DNA, 5 nucleotides from the 3΄ end of the primer terminus, HIV-1 RT could not fully replicate the template, producing truncated products; this block to further synthesis did not affect rates of dissociation or DNA binding affinity. Additionally, when the adducts were in the same relative position, but located in the template strand, similar truncated products were observed with both the C10 R and C10 S BPDE adducts. These data suggest that the presence of covalently-linked intercalative DNA adducts distant from the active site can lead to termination of DNA synthesis catalyzed by HIV-1 RT.

  4. Molecular cloning and differential expression patterns of sigma and omega glutathione S-transferases from Venerupis philippinarum to heavy metals and benzo[a]pyrene exposure

    Science.gov (United States)

    Zhang, Linbao; Wu, Huifeng; Liu, Xiaoli; Chen, Leilei; Wang, Qing; Zhao, Jianmin; You, Liping

    2012-05-01

    Glutathione S-transferases (GSTs) are a class of enzymes that facilitate the detoxification of xenobiotics, and also play important roles in antioxidant defense. We identified two glutathione S-transferase isoforms (VpGSTS, sigma GST; VpGSTO, omega GST) from Venerupis philippinarum by RACE approaches. The open reading frames of VpGSTS and VpGSTO were of 612 bp and 729 bp, encoding 203 and 242 amino acids with an estimated molecular mass of 22.88 and 27.94 kDa, respectively. The expression profiles of VpGSTS and VpGSTO responded to heavy metals and benzo[a]pyrene (B[a]P) exposure were investigated by quantitative real-time RT-PCR. The expression of VpGSTS and VpGSTO were both rapidly up-regulated, however, they showed differential expression patterns to different toxicants. Cd displayed stronger induction of VpGSTS expression with an approximately 12-fold increase than that of VpGSTO with a maximum 6.4-fold rise. Cu exposure resulted in similar expression patterns for both VpGSTS and VpGSTO. For B[a]P exposure, the maximum induction of VpGSTO was approximately two times higher than that of VpGSTS. Altogether, these findings implied the involvement of VpGSTS and VpGSTO in host antioxidant responses, and highlighted their potential as a biomarker to Cd and B[a]P exposure.

  5. The selective cleanup of complex matrices and simultaneous separation of benzo[a]pyrene by solid-phase extraction with MgO microspheres as sorbents.

    Science.gov (United States)

    Jin, Jing; Li, Yun; Zhang, Zhiping; Su, Fan; Qi, Peipei; Lu, Xianbo; Chen, Jiping

    2011-12-23

    A new method for the selective cleanup of complex matrices and simultaneous separation of benzo[a]pyrene (BaP) was developed in this study. This method was based on solid-phase extraction (SPE) using magnesium oxide microspheres as sorbents, and it eliminated interferences from various impurities, such as lipids, sulphur, pigments, halobenzenes, polychlorodibenzo-p-dioxins and polychlorodibenzofurans. Several parameters, including the volume of rinsing and eluting solvents, the type of loading solvents and SPE sorbents, were optimized systematically. The capability for impurity removal was verified by gel permeation chromatography, gas chromatography, and liquid chromatography. Compared to commercial sorbents (silica gel, florisil and alumina), MgO microspheres exhibited excellent performance in the selective isolation of BaP and removal of impurities. The proposed method was applied to detect BaP in complex samples (sediments, soils, fish, and porcine liver). The limit of quantification (LOQ) was 1.04 ngL(-1), and the resulting regression coefficient (r(2)) was greater than 0.999 over a broad concentration range (9.5-7600 ngL(-1)). In contrast to traditional methods, the proposed method can give rise to higher recovery (85.1-100.8%) and better selectivity with simpler operation and less consumption of organic solvents (20-40 mL).

  6. Effects of quantity, quality, and contact time of dissolved organic matter on bioconcentration of benzo[a]pyrene in the nematode Caenorhabditis elegans

    Energy Technology Data Exchange (ETDEWEB)

    Haitzer, M.; Hoess, S. [Ludwig Maximilians Univ. Muenchen (Germany). Zoologisches Inst.]|[Inst. fuer Gewaesseroekologie und Binnenfischerei, Berlin (Germany); Burnison, B.K. [Environment Canada, Burlington, Ontario (Canada). National Water Research Inst.; Traunspurger, W. [Ludwig Maximilians Univ. Muenchen (Germany). Zoologisches Inst.; Steinberg, C.E.W. [Inst. fuer Gewaesseroekologie und Binnenfischerei, Berlin (Germany)

    1999-03-01

    Quantity and quality of dissolved organic matter (DOM) and the time allowed for DOM to interact with organic contaminants can influence their bioavailability. The authors studied the effect of natural aquatic DOM that had been in contact with benzo[a]pyrene (B[a]P) for 1 to 12 d on the bioconcentration of B[a]P in the nematode Caenorhabditis elegans. Dissolved organic matter quality and quantity was varied by using DOM from three different sources, each in three different concentrations. A model, based on the assumption that only freely dissolved B[a]P is bioavailable, was employed to estimate biologically determined partition coefficients [K{sub p}(biol.)]. Expressing the data for each combination of DOM source and contact time in a single K{sub p} (biol.) value allowed a direct comparison of the effects of different DOM qualities and contact times. The results show that the effect of DOM from a specific source was dependent on DOM quantity, but they also observed a distinct effect of DOM quality (represented by different sampling locations) on the bioconcentration of B[a]P. Contact time had no significant influence for the effects of two DOM sources on the bioconcentration of B[a]P. However, the third DOM source was significantly more effective with increased contact time, leading to lower B[a]P bioconcentration in the nematodes.

  7. P-glycoprotein and CYP1A protein expression patterns in Nile tilapia (Oreochromis niloticus) tissues after waterborne exposure to benzo(a)pyrene (BaP).

    Science.gov (United States)

    Costa, Joana; Reis-Henriques, Maria Armanda; Wilson, Jonathan M; Ferreira, Marta

    2013-09-01

    The protein levels and tissue distribution patterns of P-glycoprotein (Pgp) and cytochrome P450 (CYP1A) were investigated in Nile tilapia (Oreochromis niloticus) after waterborne exposure to different benzo(a)pyrene (BaP) concentrations, using immunochemical approaches. The Pgp mammalian monoclonal antibody (mAb) C219 cross reacted with a ∼170kDa protein, almost exclusively localized to the bile canaliculi, while probing with the Pgp mammalian mAb C494, resulted in a positive reaction in liver, gills and intestine of Nile tilapia and covered a wider set of cell types. Levels of Pgp expression were not altered after in vivo exposure to BaP. CYP1A, detected with the mAb C10-7, reacted positively in liver, gills and intestine and followed a BaP dose-dependent fold induction. Taken together, these results indicate that CYP1A is involved in BaP metabolism in liver, gills and intestine, however, further studies are needed to elucidate the possible interaction of the efflux protein Pgp with BaP and/or its metabolites.

  8. Toxic effects of benzo[a]pyrene (Bap) and Aroclor1254 on embryogenesis, larval growth, survival and metamorphosis of the bivalve Meretrix meretrix.

    Science.gov (United States)

    Wang, Qing; Yang, Hongsheng; Liu, Baozhong; Wang, Xiaoyu

    2012-08-01

    To assess the potential toxicity of polycyclic aromatic hydrocarbons and polychlorinated biphenyls on the early development of Meretrix meretrix, the effects of benzo[a]pyrene (Bap) and Aroclor1254 on embryogenesis and larval development were investigated using static laboratory toxicity tests at nominal concentrations of 6.25-1,600 μg/L. Even at 1,600 μg/L, Bap and Aroclor1254 only caused minor reductions in embryo development rates. The 96 h LC(50) values for D-shaped larvae were 156 μg/L for Bap and 132 μg/L for Aroclor1254, respectively. The most sensitive toxicity endpoint in this study was metamorphosis, with an EC(50) value of 20 μg/L for Bap and 35 μg/L for Aroclor1254. Aroclor1254 was more toxic than Bap to embryos and larvae. Our results indicate that Bap and Aroclor1254 do not show extreme toxicity to M. meretrix embryos and larvae. These data provide information for evaluating the toxicity of Bap and Aroclor1254 on bivalve embryos, especially over the entire larval stages.

  9. A fluorescence enhancement-based label-free homogeneous immunoassay of benzo[a]pyrene (BaP) in aqueous solutions.

    Science.gov (United States)

    Li, Taihua; Choi, Yo Han; Shin, Yong-Beom; Kim, Hwa-Jung; Kim, Min-Gon

    2016-05-01

    A fluorescence enhancement-based immunoassay has been developed for the detection of the polycyclic aromatic hydrocarbons (PAH), benzo[a]pyrene (BaP), in aqueous solutions. The results of this study show that BaP, which inefficiently fluoresces in aqueous solution, displays enhanced fluorescence when bound to the anti-BaP antibody (anti-BaP), as part of a label-free immunoassay system. Binding to anti-BaP results in a 3.12-fold increase in the fluorescence intensity of BaP, which emits at 435 nm when excited at 280 nm, due to the hydrophobic interaction and fluorescence resonance energy transfer (FRET) between antibody and antigen. As result of this phenomenon, the antibody-based fluorescence immunoassay system can be used to detect BaP specifically with a limit of detection (LOD) of 0.06 ng mL(-1). Finally, extraction recoveries of BaP from spiked wheat and barley samples were found to be in the range of 80.5-87.0% and 92.9-92.1%, respectively.

  10. Burial effects of organic coatings on the heterogeneous reactivity of particle-borne benzo[a]pyrene (BaP) toward ozone.

    Science.gov (United States)

    Zhou, S; Lee, A K Y; McWhinney, R D; Abbatt, J P D

    2012-07-01

    With an aerosol flow tube coupled to an Aerodyne aerosol mass spectrometer (AMS), room temperature (296 ± 3 K) kinetics studies have been performed on the reaction of gas-phase ozone with benzo[a]pyrene (BaP) adsorbed in submonolayer amounts to dry ammonium sulfate (AS) particles. Three organic substances, i.e., bis(2-ethylhexyl)sebacate (BES, liquid), phenylsiloxane oil (PSO, liquid), and eicosane (EC, solid), were used to coat BaP-AS particles to investigate the effects of such organic coatings on the heterogeneous reactivity of PAHs toward ozone. All the reactions of particle-borne BaP with excess ozone exhibit pseudo-first-order kinetics in terms of BaP loss, and reactions with a liquid organic coating proceed by the Langmuir-Hinshelwood (L-H) mechanism. Liquid organic coatings did not significantly affect the kinetics, consistent with the ability of reactants to rapidly diffuse through the organic coating. In contrast, the heterogeneous reactivity of BaP was reduced substantially by a thin (4-8 nm), solid EC coating and entirely suppressed by thick (10-80 nm) coatings, presumably because of slow diffusion through the organic layer. Although the heterogeneous reactivity of surface-bound PAHs is extremely rapid in the atmosphere, this work is the first to experimentally demonstrate a mechanism by which the lifetime of PAHs may be significantly prolonged, permitting them to undergo long-range transport to remote locations.

  11. Degradation of 14C labelled Benzo[a]pyrene by a PAH-adapted mixed bacterial culture in the presence of an alkylpolyglycoside-surfactant

    International Nuclear Information System (INIS)

    The biodegradation of the five ring PAH benzo[a]pyrene (BaP) is assumed to be limited by the low water solubility of this compound. A mixed culture of microorganisms - isolated from a PAH-contaminated soil - was able to degrade 14C labelled BaP in mineral medium by co-metabolism with phenanthrene, fluoranthene, anthracene and pyrene as sources of carbon and energy. The mineralisation of these compounds to low levels resulted in an inhibition of the degradation of BaP. After the new addition of the four PAH compounds to the culture medium the mineralisation of BaP started again. A non-ionic surfactant of the alkylpolyglycoside type (Plantacare 2000 UP) increased the concentration of BaP in the culture medium because of solubilization. At high Plantacare concentrations, the degradation of BaP was completely inhibited above the critical micelle concentration (cms). The degradation of the three and four ring PAHs was also inhibited. If the surfactant was metabolised to concentrations below the cmc, an increase of mineralisation of BaP could occur up to 24% in 384 days. (orig.)

  12. Estimation of a lifetime unit lung cancer risk for benzo(a)pyrene based on tumour rates in rats exposed to coal tar/pitch condensation aerosol.

    Science.gov (United States)

    Heinrich, U; Roller, M; Pott, F

    1994-06-01

    Female Wistar rats were exposed to coal tar/pitch condensation (CTP) aerosol containing either 20 or 46 micrograms/m3 benzo(a)pyrene (BaP) among other polycyclic aromatic hydrocarbons (PAH) 17 h/day and 5 days/week for 10 or 20 months followed by a clean air period of up to 20 or 10 months, respectively. Based on the inhaled BaP, given as BaP exposure concentration multiplied by the total exposure time, the cumulative dose of inhaled BaP of the 4 exposure groups was 71, 142, 158 and 321 mg BaP/m3 x h and the corresponding lung tumour rates were 4.2, 33.3, 38.9 and 97.2%. There was no lung tumour in the control group. Using the US Environmental Protection Agency (EPA) linearized multistage model, the lifetime lung tumour risk for rats exposed to 1 microgram/m3 BaP as a constituent of a complex PAH mixture may be 2% or correspondingly 2 per 100,000 with a BaP concentration of 1 ng/m3. The estimation of the unit lung cancer risk for BaP based on epidemiological data from coking plants was 7-9%.

  13. The combined toxicity of dibutyl phthalate and benzo(a)pyrene on the reproductive system of male Sprague Dawley rats in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Chen Xuemei [Laboratory of Reproductive Biology, Chongqing Medical University, Chongqing 400016 (China); An Hui; Ao Lin; Sun Lei; Liu Wenbin; Zhou Ziyuan [Department of Hygenic Toxicology, College of Military Preventive Medicine, Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Third Military Medical University, Chongqing 400038 (China); Wang Yingxiong, E-mail: wyx61221@yahoo.com.cn [Laboratory of Reproductive Biology, Chongqing Medical University, Chongqing 400016 (China); Cao Jia, E-mail: caojia1962@126.com [Department of Hygenic Toxicology, College of Military Preventive Medicine, Key Lab of Medical Protection for Electromagnetic Radiation, Ministry of Education of China, Third Military Medical University, Chongqing 400038 (China)

    2011-02-15

    Our previous studies revealed more than 100 pollutants, most of which were endocrine disruptors (EDs) in two Chinese rivers, the Jialing and the Yangtze near Chongqing. Most EDs, such as dibutyl phthalate (DBP) and benzo(a)pyrene (BaP), are known to act individually as reproductive toxicants. However, little is known about the combined toxicity of DBP and BaP. In the current study, male Sprague Dawley rats were subchronically exposed to single doses of DBP (250 mg/kg), single doses of BaP (5 mg/kg) and combined doses of DBP and BaP. Significant adverse effects were observed on the reproductive system, including decreased sperm count, increased production of abnormal sperm, changes in serum testosterone levels and irregular arrangements of the seminiferous epithelium. Biochemical analyses showed that the activities of superoxide dismutase and glutathione peroxidase decreased after exposure to these EDs. Therefore, our data suggest that exposure to DBP and BaP, in either separate or combined doses, can affect the reproductive system of male rats adversely via oxidative stress-related mechanisms. No significant additive effect was observed after combined exposure. These results indicate that exposure to mixtures of EDs have unexpected and elusive effects. Our findings provide preliminary but important data for assessing water safety in China.

  14. EFFECTS OF LIMONENE, SALVIA MILTIORRHIZA AND TURMERIC DERIVATIVES ON H-RAS ONCOGENE EXPRESSION AND GAP JUNCTION INTERCELLULAR COMMUNICATION IN HUMAN SOLID TUMOR CELL LINES

    Institute of Scientific and Technical Information of China (English)

    Chen Xiaoguang; Taday oshi Hasuma; Yoshihisa Yano; Toshiko Yoshimata; Hiyoshi Kamoi; Shuzo Otani

    1998-01-01

    Objective: To study gap junction intercellular communication (GJIC), H-ras oncogene expression and ras oncogene product (P21 ras protein) expression in four human solid tumor cell lines, W1-38, CACO2, A549 and PaCa, and the effects of four compounds, Salvia miltiorrhiza derivative (SMD), d-Limonene, Turmeric derivative Ⅰ (TD-Ⅰ) and Turmeric derivative Ⅱ (TD-Ⅱ), on them. Methods: The abilities of the four solid tumor cell lines to transfer dye to adjacent cells were examined by the scrape-loading/dye transfer technique, and the Hras oncogene expression by Northern blotting and P21 ras protein expression by Western blotting. Results: The results showed the loss of intercellular coupling in PaCa cells, slight GJIC in A549 and CACO2 cells, and a good GJIC in W1-38 cells. The four compounds could improve the GJIC of PaCa to different extents. The amount of total and membrane associated P21 ras in PaCa cells were decreased after treatment with SMD, d-Limonene and TD-Ⅰ (2.5 μg/ml) for 48 h. Concomitantly, the growth of PaCa cells decreased in soft agar and had enhanced GJIC.The relative potency was found to be:d-Limonene>SMD >TD-Ⅰ=TD-Ⅱ. There was no significant effect of the four compounds on H-ras oncogene expression. Conclusion:It was suggested that there was an excellent correlation between loss of Lucifer Yellow dye transfer and ras gene mutation rate in the four solid tumor cell lines (ras gene mutation rate inversely correlated with average cell number coupled, r=0.98) i.e., the high ras gene mutation was closely correlated with loss of GJIC in these malignant human tumor cells; The antitumor effect of the monoterpene d-Limonene and the phenol compound,SMD, might be related to inhibition of P21 ras membrane association and enhancement of GJIC, whilst that of the others may be by a different mechanism; The inhibition of p21 ras membrane association was directly related to the enhancement of gap junction intercellular communication.

  15. Histomorphological and Immunophenotypic Features of Pill-Induced Esophagitis.

    Directory of Open Access Journals (Sweden)

    Ji Won Kim

    Full Text Available The aim of this study was to investigate histomorphological and immunophenotypic features in pill-induced esophagitis. We comparatively evaluated the histomorphological, immunophenotypic features of pill-induced esophagitis vs. reflux esophagitis, as well as clinical information and endoscopic findings. Fifty-two tissue pieces from 22 cases of pill-induced esophagitis, 46 pieces from 20 reflux esophagitis, and 16 pieces from 14 control samples were subjected to immunohistochemistry for inflammatory infiltrates (CD3 for T lymphocyte, CD20 for B lymphocyte, CD56 for NK cell, CD68 for macrophage, CD117 for mast cell and eosinophil chemotaxis-associated proteins (Erk, leptin, leptin receptor, pSTAT3, phospho-mTOR. As a result, Histomorphology showed that a diffuse pattern of dilated intercellular spaces was more frequently observed in pill-induced esophagitis, while reactive atypia and subepithelial papillary elongation were more often found in reflux esophagitis (P < 0.05, respectively. Interestingly, intraepithelial eosinophilic microabscess, intraepithelial pustule and diffuse pattern of dilated intercellular spaces were observed in 14% (3 cases, 9% (2 cases and 32% (7 cases of pill-induced esophagitis, respectively, but in no cases of reflux esophagitis. Regarding intraepithelial inflammatory infiltrates in pill-induced esophagitis, T lymphocytes were the most common cells, followed by eosinophil; 11 and 7 in one x400 power field, respectively. Intraepithelial pSTAT3-positive pattern was more frequently observed in pill-induced esophagitis than in reflux esophagitis, at 45% (10 cases versus 10% (2 cases, respectively (P < 0.05. Considering the distal esophageal lesion only, intraepithelial pustule, diffuse dilated intercellular spaces and stromal macrophages were more frequently found in distal pill-induced esophagitis, whereas reactive atypia and intraepithelial mast cells in reflux esophagitis (P < 0.05, respectively. In conclusion, diffuse

  16. Effect of various metals on intercellular adhesion molecule-1 expression and tumour necrosis factor alpha production by normal human keratinocytes.

    Science.gov (United States)

    Guéniche, A; Viac, J; Lizard, G; Charveron, M; Schmitt, D

    1994-01-01

    Nickel, cobalt and chromium are metals very often implicated in allergic contact dermatitis. In vivo, keratinocytes, which are the first target cells, can be directly activated to participate in the local reaction, especially through the expression of the membrane antigen ICAM-1, a ligand of the leucocyte antigen LFA-1, and the production of cytokines. Our aim was to assess the effects of sensitizing metal haptens (nickel, cobalt and chromium) compared with the toxic metal cadmium on the induction of ICAM-1 and the production of TNF alpha by epidermal cells. For this purpose, normal human keratinocytes obtained during plastic skin surgery were cultured in low-calcium defined medium (MCDB153) and the metals were used in non-toxic concentrations. Using FACS analysis, ICAM-1 expression was found to be induced only by nickel. This stimulation appeared as early as 24 h after stimulation. All the metals induced a low expression of TNF alpha detectable by immunocytochemistry correlating with the induction of the nuclear stress protein Hsp72 which is closely linked genetically with the TNF alpha locus. However, only Ni2+, Co2+ and Cr2+ induced a significant release of TNF alpha detectable by ELISA after 48 h stimulation. This secretion was lower than that observed with known stimulants such as lipopolysaccharide. These results indicate that the metals studied are able to induce an aggressive cellular effect, and that nickel, by its ICAM-1 induction, may play a major role in the keratinocyte activation state during allergic contact dermatitis. PMID:7864660

  17. Soluble intercellular adhesion molecule-1 (sICAM-1) and soluble interleukin-2 receptors (sIL-2R) in scleroderma skin

    DEFF Research Database (Denmark)

    Søndergaard, Klaus; Deleuran, Mette; Heickendorff, Lene;

    1998-01-01

    In order to investigate whether soluble intercellular adhesion molecule-1 (sICAM-1) and soluble interleukin-2 receptors (sIL-2R) were present in scleroderma skin, and to compare their levels to concentrations measured in plasma and clinical parameters, we examined suction blister fluid and plasma...... from 13 patients with systemic sclerosis and 11 healthy volunteers. Suction blisters and biopsies were from the transition zone between normal skin and scleroderma, and uninvolved abdominal skin. The levels of sICAM-1 and sIL-2R were significantly increased in both plasma and suction blister fluid from...... systemic sclerosis patients compared with healthy volunteers. ICAM-1 was localized to vessels and perivascular mononuclear infiltrates by immunohistochemical methods. IL-2R was expressed by CD3-positive cells. The elevated levels of sICAM-1 and sIL-2R in suction blister fluid point towards activation...

  18. The Tumor Antigen NY-ESO-1 Mediates Direct Recognition of Melanoma Cells by CD4+ T Cells after Intercellular Antigen Transfer.

    Science.gov (United States)

    Fonteneau, Jean Francois; Brilot, Fabienne; Münz, Christian; Gannagé, Monique

    2016-01-01

    NY-ESO-1-specific CD4(+) T cells are of interest for immune therapy against tumors, because it has been shown that their transfer into a patient with melanoma resulted in tumor regression. Therefore, we investigated how NY-ESO-1 is processed onto MHC class II molecules for direct CD4(+) T cell recognition of melanoma cells. We could rule out proteasome and autophagy-dependent endogenous Ag processing for MHC class II presentation. In contrast, intercellular Ag transfer, followed by classical MHC class II Ag processing via endocytosis, sensitized neighboring melanoma cells for CD4(+) T cell recognition. However, macroautophagy targeting of NY-ESO-1 enhanced MHC class II presentation. Therefore, both elevated NY-ESO-1 release and macroautophagy targeting could improve melanoma cell recognition by CD4(+) T cells and should be explored during immunotherapy of melanoma.

  19. Black tattoos protect against UVR-induced skin cancer in mice

    DEFF Research Database (Denmark)

    Lerche, Catharina M; Sepehri, Mitra; Serup, Jørgen;

    2015-01-01

    BACKGROUND: Black tattoos may involve risk of cancer owing to polycyclic aromatic hydrocarbons including benzo(a)pyrene (BaP) in inks. Ultraviolet radiation (UVR) induces skin cancer. The combination of UVR and black tattoo may therefore potentially be very problematic, but has not been previously...... studied. METHODS: Immunocompetent C3.Cg/TifBomTac mice (n = 99) were tattooed on the back with Starbrite Tribal Black(™) . This ink has a high content of the carcinogen BaP. Half of the mice were irradiated with three standard erythema doses UVR thrice weekly. Time to induction of first, second and third...

  20. Fisetin increases the cytotoxicity of cisplatin by enhancing gap junctional intercellular communication%漆黄素通过缝隙连接影响顺铂细胞毒性

    Institute of Scientific and Technical Information of China (English)

    杨克凡; 范丽霞; 彭悦霞; 王琴; 陶亮

    2015-01-01

    Aim To investigate the effect of fisetin on the cytotoxicity of cisplatin and its mechanisms. Meth-ods CCK-8 was used to assay the toxicity of fisetin.“Parachute” dye-coupling assay was used to examine dye spread through gap junctions in U87 cells. “Stand-ard colony-forming assay” was used to examine cell survivals of U87 treated with cisplatin with fisetin. Western blot was performed to detect the expression level of Cx43 . Results Fisetin had no cytotoxic effect on U87 cells at the concentration of 0~1μmol · L-1 . Parachute assay demonstrated that fisetin enhanced dye-coupling through gap juntions in U87 cells. Stand-ard Colony forming assay showed that cisplatin inhibi- ted the clonogenic survivals of U87 cells and fisetin could enhance cisplatin-induced inhibitory effect of clo-nogenic survivals on cells with gap junctional formation more than on cells without gap junctional formation. Conclusion These rusults demonstrate that fisetin could increase the sensitivity of glioma cells to cisplatin through the enhancement of gap junctional intercellular communication but this may not be related to the ex-pression of Cx43 .%目的:体外观察漆黄素对顺铂细胞毒性作用影响及其机制。方法 CCK-8法观察不同浓度漆黄素对人胶质瘤U87细胞的毒性;用细胞接种荧光示踪法测定不同浓度漆黄素对U87细胞缝隙连接( GJ )功能的影响;标准细胞集落形成分析法观察顺铂的毒性及漆黄素对顺铂毒性的影响;用Western blot法研究漆黄素在影响GJIC( GJ intercellular com-munication)功能浓度范围内对 Cx43表达的影响。结果CCK-8法显示漆黄素在小于1μmol·L-1的浓度范围内无细胞毒性;细胞接种荧光示踪法显示漆黄素浓度越高, U87细胞GJ通讯的荧光传递功能越强;标准细胞集落形成分析法显示,20μmol·L-1顺铂能够抑制U87细胞的集落形成,而且在有GJ形成的细胞顺铂对细胞集落形成的抑制作用显著

  1. The relationship between wall tension, lamellar thickness, and intercellular junctions in the fetal and adult aorta: its relevance to the pathology of dissecting aneurysm.

    Science.gov (United States)

    Berry, C L; Sosa-Melgarejo, J A; Greenwald, S E

    1993-01-01

    It is known that the distribution of stress and strain in the vessel wall is not uniform. We believe that this explains the location of the plane of dissection in dissecting aneurysms of large elastic arteries. We have investigated the effects of non-uniformity of stress and strain on the thickness of each elastic lamella and on the distribution of intercellular junctions in the media of developing and adult rats, to seek evidence to support this hypothesis. Intercellular junctions were identified by transmission electron microscopy of whole wall sections. A morphometric study of elastic tissue distribution was made on an image analysis computer. Differences were analysed using one-way analysis of variance. There are between six and eight elastic lamellae in the aorta of rats. In the fetus, only the internal elastic lamella is complete; the others were not fully formed by term. In the adult, the inner five elastic lamellae were thicker than the remaining two or three, and smooth muscle cells in the thicker lamellar units had more cell-cell contacts of all types examined. These data support the concept of a difference in stress-resisting properties of the aortic wall on the junctions between the inner two-thirds and the outer third of the media. The findings indicate that, as proposed in theoretical models the innermost lamellae support the high tension. In the adult aorta, the structure is modified to enhance the capacity to resist stress in the internal two-thirds of the media.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8433211

  2. Proteomic analysis of HIV-1 Nef cellular binding partners reveals a role for exocyst complex proteins in mediating enhancement of intercellular nanotube formation

    Directory of Open Access Journals (Sweden)

    Mukerji Joya

    2012-06-01

    Full Text Available Abstract Background HIV-1 Nef protein contributes to pathogenesis via multiple functions that include enhancement of viral replication and infectivity, alteration of intracellular trafficking, and modulation of cellular signaling pathways. Nef stimulates formation of tunneling nanotubes and virological synapses, and is transferred to bystander cells via these intercellular contacts and secreted microvesicles. Nef associates with and activates Pak2, a kinase that regulates T-cell signaling and actin cytoskeleton dynamics, but how Nef promotes nanotube formation is unknown. Results To identify Nef binding partners involved in Pak2-association dependent Nef functions, we employed tandem mass spectrometry analysis of Nef immunocomplexes from Jurkat cells expressing wild-type Nef or Nef mutants defective for the ability to associate with Pak2 (F85L, F89H, H191F and A72P, A75P in NL4-3. We report that wild-type, but not mutant Nef, was associated with 5 components of the exocyst complex (EXOC1, EXOC2, EXOC3, EXOC4, and EXOC6, an octameric complex that tethers vesicles at the plasma membrane, regulates polarized exocytosis, and recruits membranes and proteins required for nanotube formation. Additionally, Pak2 kinase was associated exclusively with wild-type Nef. Association of EXOC1, EXOC2, EXOC3, and EXOC4 with wild-type, but not mutant Nef, was verified by co-immunoprecipitation assays in Jurkat cells. Furthermore, shRNA-mediated depletion of EXOC2 in Jurkat cells abrogated Nef-mediated enhancement of nanotube formation. Using bioinformatic tools, we visualized protein interaction networks that reveal functional linkages between Nef, the exocyst complex, and the cellular endocytic and exocytic trafficking machinery. Conclusions Exocyst complex proteins are likely a key effector of Nef-mediated enhancement of nanotube formation, and possibly microvesicle secretion. Linkages revealed between Nef and the exocyst complex suggest a new paradigm of

  3. OSCILLATING FLUID FLOW ACTIVATION OF GAP JUNCTION HEMICHANNELS INDUCES ATP RELEASE FROM MLO-Y4 OSTEOCYTES

    OpenAIRE

    Genetos, Damian C.; Kephart, Curtis J.; Zhang, Yue; Yellowley, Clare E.; Donahue, Henry J.

    2007-01-01

    Mechanical loads are required for optimal bone mass. One mechanism whereby mechanical loads are transduced into localized cellular signals is strain-induced fluid flow through lacunae and canaliculi of bone. Gap junctions (GJ) between osteocytes and osteoblasts provides a mechanism whereby flow-induced signals are detected by osteocytes and transduced to osteoblasts. We have demonstrated the importance of GJ and gap junctional intercellular communication (GJIC) in intracellular calcium and pr...

  4. Metabolic enzyme activities, metabolism-related genes expression and bioaccumulation in juvenile white shrimp Litopenaeus vannamei exposed to benzo[a]pyrene.

    Science.gov (United States)

    Ren, Xianyun; Pan, Luqing; Wang, Lin

    2014-06-01

    The purpose of this study was to investigate the impact of benzo[a]pyrene (BaP) on metabolic detoxification system and bioaccumulation of white shrimp Litopenaeus vannamei. In this study, juvenile white shrimp L. vannamei were exposed for 21 days at four different concentrations of 0, 0.03, 0.3 and 3μg/L. Detoxification enzyme activities of phase I (aryl hydrocarbon hydroxylase (AHH), 7-ethoxyresorufin O-deethylase (EROD), epoxide hydrolase (EH)) and phase II (glutathione-S-transferase (GST), sulfotransferase (SULT), uridine diphosphate glucuronyl transferase (UGT)) were determined, and results showed that all the detoxification enzyme activities increased in a dose-dependent manner except for the low BaP exposure. Transcription of genes was detected and measured by real-time RT-PCR. It showed that at day six BaP increased cytochrome P450 (CYP) 1A1, GST, SULT visa aryl hydrocarbon receptor (AhR) mRNA expression in a dose-dependent manner, which suggests that they could be potential targets of BaP that disrupt the detoxification system. The consistency of their responses to BaP exposure implies that AhR action may be involved in invertebrate CYP regulation. Additionally, BaP bioaccumulation increased rapidly first and showed an incoming plateau. Besides, the enzyme activities and bioaccumulation in the hepatopancreas were higher than those in the gills. These results will not only provide information on BaP metabolic mechanism for this species, but also scientific data for pollution monitoring. PMID:24636950

  5. Benzo(a)pyrenediolepoxide-hemoglobin adducts and 3-hydroxy-benzo(a)pyrene urinary excretion profiles in rats subchronically exposed to benzo(a)pyrene.

    Science.gov (United States)

    Bouchard, M; Viau, C

    1995-01-01

    The time profiles of benzo(a)pyrenediolepoxide (BaPDE)-hemoglobin (Hb) adduct formation and 3-hydroxybenzo(a)pyrene (3-OHBaP) urinary excretion were studied in male Sprague-Dawley rats exposed to daily benzo(a)pyrene (BaP) intraperitoneal doses of 1.25, 6.25, and 31.25 mumol/kg administered Tuesday to Friday for 4 consecutive weeks. Blood was withdrawn weekly, on Tuesdays, prior to dosing. Twenty-four-hour urine samples were collected on Mondays (following 72 h without treatment) and Thursdays. Analytes were quantified by high performance liquid chromatography (HPLC)/fluorescence. Exposure to BaP resulted in the accumulation of BaPDE-Hb adducts, reaching an average of 1.2 +/- 0.3, 8.3 +/- 1.9, and 38.2 +/- 6.1 pmol/g Hb for the 1.25, 6.25, and 31.25 mumol/kg per day doses after 4 weeks of treatment. The expected saw tooth excretion profile of 3-OHBaP was observed, with peaks on Thursdays and troughs on Mondays, and showed a progressive rise on both Mondays and Thursdays. Increase in Monday values with time suggested a possible increase in BaP body burden during exposure. To verify this aspect further, the urinary excretion kinetic of 3-OHBaP following acute intraperitoneal dosing (31.25 mumol/kg) was determined. Urine samples were collected at frequent timed intervals for up to 164 h post-dosing. Two-step elimination was observed, the second step having a half-life of 25 h, presumably linked to the slow release of BaP accumulated in fatty tissues upon repeated treatment.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8534197

  6. Rapid determination of benzo[a]pyrene by membrane enrichment coupled with solid-phase constant-wavelength synchronous fluorescence spectrometry.

    Science.gov (United States)

    Wang, Lei; Li, Wei; Zhang, Feiyu; Li, Hui; Cai, Guimin; Li, Bing; Qian, Guangbei; Du, Yiping

    2016-09-01

    Normal methods for benzo[a]pyrene (BaP) determination, including gas chromatography-mass spectrometry and liquid chromatography with fluorescence detection, involve expensive instruments and complex separation and purification processes. Based on membrane enrichment, coupled with solid-phase constant-wavelength synchronous fluorescence spectrometry, a simple, fast, sensitive method was proposed for the determination of BaP in water samples. A Nylon membrane was used as the solid-phase extraction material for enrichment. After enrichment, a constant-wavelength synchronous fluorescence spectrum was scanned directly on the membrane-concentrated BaP without elution. Spectral measurement and enrichment conditions were optimized. Under optimum conditions, when using 150 mL sample solutions, the relationship between fluorescence intensity and BaP concentrations in the 0.05-10.00 μg L(-1) range could be fitted by binomial function with an R(2) value of 0.9973. Limit of detection (LOD) was calculated to be 0.0137 μg L(-1) . The volume of the sample solution was increased to 1000 mL to test if the method could be applied to determine lower BaP concentrations. A linear relationship still existed in the range 2.0-20.0 ng L(-1) BaP with an R(2) value of 0.9895, and a LOD of 2.4 ng L(-1) . The method was also used to measure the BaP concentration in several natural water samples, and recoveries were in the 90-110% range with relative standard deviations (RSDs) in the 0.58-7.93% range. Copyright © 2016 John Wiley & Sons, Ltd. PMID:26781918

  7. Sensitivity analysis of biodiesel blends on Benzo[a]pyrene and main emissions using MOVES: A case study in Temuco, Chile.

    Science.gov (United States)

    Pino-Cortés, Ernesto; Díaz-Robles, Luis A; Cubillos, Francisco; Fu, Joshua S; Vergara-Fernández, Alberto

    2015-12-15

    Temuco is one of the most highly wood-smoke polluted cities in Chile; however, the diesel mobile sources are growing very fast in the past 10 years and so far very few studies have been done. The main goal of this research was to develop a 2013 emission inventory of criteria pollutants and Benzo[a]pyrene (BaP) and to evaluate the use of six biodiesel blends of 0%, 1%, 4%, 8%, 12%, and 20% by volume of fuel in diesel motors from the vehicle fleet within the mentioned areas using the Motor Vehicle Emission Simulator (MOVES). Input parameters for the base year 2005 were estimated to implement and adapt the model in Chile, while results of NOx, PM10, PM2.5, NH3, CO2 equivalent and SO2 were compared with the Chilean Emission Inventory estimated by the model "Methodology for the Calculation of Vehicle Emissions." The 2013 emissions reduced with respect to 2005, in the majority of the contaminants analyzed, despite the 47% increase in the annual miles traveled. Using biodiesel blends, an emission reduction was estimated at up to 15% in particulate matter, BaP, and CO for the year 2013, as well as an increment of 2% in NOx emissions, attributed to low sulfur content (50 ppm) in the diesel and the antiquity of the vehicle fleet. The results obtained gave evidence of the influence of the biodiesel use in the pollutant emissions to improve the Chilean air quality, as well as providing a strategy for this air quality management.

  8. Fullerene inhibits benzo(a)pyrene Efflux from Cyprinus carpio hepatocytes by affecting cell membrane fluidity and P-glycoprotein expression.

    Science.gov (United States)

    Chen, Qiqing; Hu, Xialin; Wang, Rui; Yuan, Jin; Yin, Daqiang

    2016-05-01

    P-Glycoprotein (P-gp) can protect cells by pumping out toxic compounds, and has been found widely expressed in fish tissues. Here, we illustrate the P-gp efflux ability for benzo(a)pyrene (BaP) in the hepatocytes of common carp (Cyprinus carpio) after exposing to fullerene aqueous suspension (nC60). The results revealed that nC60 increased the membrane fluidity by decreasing the ratio of saturated to unsaturated fatty acids, and increased the cholesterol contents. These findings, combined with 10-38% and 70-75% down-regulation of P-gp mRNA and protein respectively, suggested that nC60 caused inhibition on P-gp efflux transport system. Therefore, we further investigated the cellular efflux ability for BaP. Results showed unequivocally that nC60 is a potent P-gp inhibitor. The retaining BaP amounts after efflux were elevated by 1.7-2.8 fold during the 10 day exposure. Meanwhile, 5mg/L humic acid (one of the important fractions of natural organic matter, which is ubiquitous in aquatic environment) alleviated the nC60 damage to hepatocytes in terms of oxidative damage, cholesterol increment, and P-gp content reduction; and finally attenuated the suppressed P-gp efflux ability. Collectively, this study provides the first evidence of nC60 toxicity to P-gp functionality in fish and illustrates the possible mechanism of the suppressed P-gp efflux ability for BaP.

  9. Noncovalent interactions of a benzo[a]pyrene diol epoxide with DNA base pairs: insight into the formation of adducts of (+)-BaP DE-2 with DNA.

    Science.gov (United States)

    Hargis, Jacqueline C; Schaefer, Henry F; Houk, K N; Wheeler, Steven E

    2010-02-01

    Noncovalent complexes of a tumorigenic benzo[a]pyrene diol epoxide with the guanine-cytosine (GC) and adenine-thymine (AT) base pairs have been examined computationally. (+)-BaP DE-2 forms covalent adducts with DNA via nucleophilic attack on the (+)-BaP DE-2 epoxide. Computational results predict five thermodynamically accessible complexes of AT with (+)-BaP DE-2 that are compatible with intact DNA. Among these, two are expected to lead to adenine adducts. In the lowest energy AT...(+)-BaP DE-2 complex, which has a gas-phase interaction energy of -20.9 kcal mol(-1), the exocyclic NH(2) of adenine is positioned for backside epoxide attack and formation of a trans adduct. The most energetically favorable complex leading to formation of a cis ring-opened adduct lies only 0.6 kcal mol(-1) higher in energy. For GC...(+)-BaP DE-2, there are only two thermodynamically accessible complexes. The higher-lying complex, bound in the gas phase by 24.4 kcal mol(-1) relative to separated GC and (+)-BaP DE-2, would lead to a trans ring-opened N(2)-guanine adduct. In the global minimum energy GC...(+)-BaP DE-2 complex, bound by 27.3 kcal mol(-1), the exocyclic NH(2) group of cytosine is positioned for cis epoxide addition. However, adducts of (+)-BaP DE-2 with cytosine are rarely observed experimentally. The paucity of cytosine adducts, despite the predicted thermodynamic stability of this GC...(+)-BaP DE-2 complex, is attributed to the electrostatic destabilization of the benzylic cation intermediate thought to precede cis addition.

  10. Embryotoxic effects of benzo[a]pyrene, chrysene and 7,12-dimethylbenz[a]-anthracene in petroleum hydrocarbon mixtures in mallard ducks

    Science.gov (United States)

    Hoffman, D.J.; Gay, M.L.

    1981-01-01

    Studies with different avian species have revealed that surface applications of microliter amounts of some crude and fuel oils that coat less than 70% of the egg surface result in considerable reduction in hatching with teratogenicity and stunted growth. Other stUdies have shown that the embryo toxicity is dependent on the aromatic hydrocarbon content, further suggesting that the toxicity is due to causes other than asphyxia. In the present study the effects of three polycyclic aromatic hydrocarbons identified in petroleum were examined on mallard (Anas platyrhynchos) embryo development. Addition of benzo[a]pyrene (BaP), chrysene, or 7,7 2-dimethylbenz[ a]anthracene (DMBA) to a synthetic petroleum hydrocarbon mixture of known composition and relatively low embryotoxicity resulted in embryo toxicity that was enhanced or equal to that of crude oil when 10 :I was applied externally to eggs at 72 h of development. The order of ability to enhance embryo toxicity was DMBA > BaP > chrysene. The temporal pattern of embryonic death was similar to that reported after exposure to crude oil, with additional mortality occurring after outgrowth of the chorioallantois. Retarded growth, as reflected by embryonic body weight, crown-rump length, and bill length, was accompanied by teratogenicity. Abnormal embryos exhibited extreme stunting; eye, brain, and bill defects; and incomplete ossification. Gas chromatographic-mass spectral analysis of externally treated eggs showed the passage of aromatic hydrocarbons including chrysene through the shell and shell membranes to the developing embryos. These findings suggest that the presence of polycyclic aromatic hydrocarbons in petroleum, including BaP, chrysene, and DMBA, significantly enhances the overall embryotoxicity in avian species.

  11. Seasonal variation of benzo(a)pyrene in the Spanish airborne PM10. Multivariate linear regression model applied to estimate BaP concentrations.

    Science.gov (United States)

    Callén, M S; López, J M; Mastral, A M

    2010-08-15

    The estimation of benzo(a)pyrene (BaP) concentrations in ambient air is very important from an environmental point of view especially with the introduction of the Directive 2004/107/EC and due to the carcinogenic character of this pollutant. A sampling campaign of particulate matter less or equal than 10 microns (PM10) carried out during 2008-2009 in four locations of Spain was collected to determine experimentally BaP concentrations by gas chromatography mass-spectrometry mass-spectrometry (GC-MS-MS). Multivariate linear regression models (MLRM) were used to predict BaP air concentrations in two sampling places, taking PM10 and meteorological variables as possible predictors. The model obtained with data from two sampling sites (all sites model) (R(2)=0.817, PRESS/SSY=0.183) included the significant variables like PM10, temperature, solar radiation and wind speed and was internally and externally validated. The first validation was performed by cross validation and the last one by BaP concentrations from previous campaigns carried out in Zaragoza from 2001-2004. The proposed model constitutes a first approximation to estimate BaP concentrations in urban atmospheres with very good internal prediction (Q(CV)(2)=0.813, PRESS/SSY=0.187) and with the maximal external prediction for the 2001-2002 campaign (Q(ext)(2)=0.679 and PRESS/SSY=0.321) versus the 2001-2004 campaign (Q(ext)(2)=0.551, PRESS/SSY=0.449).

  12. Uncertainty evaluation for the quantification of low masses of benzo[a]pyrene: Comparison between the Law of Propagation of Uncertainty and the Monte Carlo method.

    Science.gov (United States)

    Sega, Michela; Pennecchi, Francesca; Rinaldi, Sarah; Rolle, Francesca

    2016-05-12

    A proper evaluation of the uncertainty associated to the quantification of micropollutants in the environment, like Polycyclic Aromatic Hydrocarbons (PAHs), is crucial for the reliability of the measurement results. The present work describes a comparison between the uncertainty evaluation carried out according to the GUM uncertainty framework and the Monte Carlo (MC) method. This comparison was carried out starting from real data sets obtained from the quantification of benzo[a]pyrene (BaP), spiked on filters commonly used for airborne particulate matter sampling. BaP was chosen as target analyte as it is listed in the current European legislation as marker of the carcinogenic risk for the whole class of PAHs. MC method, being useful for nonlinear models and when the resulting output distribution for the measurand is non-symmetric, can particularly fit the cases in which the results of intrinsically positive quantities are very small and the lower limit of a desired coverage interval, obtained according to the GUM uncertainty framework, can be dramatically close to zero, if not even negative. In the case under study, it was observed that the two approaches for the uncertainty evaluation provide different results for BaP masses in samples containing different masses of the analyte, MC method giving larger coverage intervals. In addition, in cases of analyte masses close to zero, the GUM uncertainty framework would give even negative lower limit of uncertainty coverage interval for the measurand, an unphysical result which is avoided when using MC method. MC simulations, indeed, can be configured in a way that only positive values are generated thus obtaining a coverage interval for the measurand that is always positive. PMID:27114218

  13. Sensitivity analysis of biodiesel blends on Benzo[a]pyrene and main emissions using MOVES: A case study in Temuco, Chile.

    Science.gov (United States)

    Pino-Cortés, Ernesto; Díaz-Robles, Luis A; Cubillos, Francisco; Fu, Joshua S; Vergara-Fernández, Alberto

    2015-12-15

    Temuco is one of the most highly wood-smoke polluted cities in Chile; however, the diesel mobile sources are growing very fast in the past 10 years and so far very few studies have been done. The main goal of this research was to develop a 2013 emission inventory of criteria pollutants and Benzo[a]pyrene (BaP) and to evaluate the use of six biodiesel blends of 0%, 1%, 4%, 8%, 12%, and 20% by volume of fuel in diesel motors from the vehicle fleet within the mentioned areas using the Motor Vehicle Emission Simulator (MOVES). Input parameters for the base year 2005 were estimated to implement and adapt the model in Chile, while results of NOx, PM10, PM2.5, NH3, CO2 equivalent and SO2 were compared with the Chilean Emission Inventory estimated by the model "Methodology for the Calculation of Vehicle Emissions." The 2013 emissions reduced with respect to 2005, in the majority of the contaminants analyzed, despite the 47% increase in the annual miles traveled. Using biodiesel blends, an emission reduction was estimated at up to 15% in particulate matter, BaP, and CO for the year 2013, as well as an increment of 2% in NOx emissions, attributed to low sulfur content (50 ppm) in the diesel and the antiquity of the vehicle fleet. The results obtained gave evidence of the influence of the biodiesel use in the pollutant emissions to improve the Chilean air quality, as well as providing a strategy for this air quality management. PMID:26282769

  14. Molecular cloning and differential expression patterns of sigma and omega glutathione S-transferases from Venerupis philippinarum to heavy metals and benzo[a]pyrene exposure

    Institute of Scientific and Technical Information of China (English)

    ZHANG Linbao; WU Huifeng; LIU Xiaoli; CHEN Leilei; WANG Qing; ZHAO Jianmin; YOU Liping

    2012-01-01

    Glutathione S-transferases (GSTs) are a class of enzymes that facilitate the detoxification of xenobiotics,and also play important roles in antioxidant defense.We identified two glutathione S-transferase isoforms (VpGSTS,sigma GST; VpGSTO,omega GST) from Venerupis philippinarum by RACE approaches.The open reading frames of VpGSTS and VpGSTO were of 612 bp and 729 bp,encoding 203 and 242 amino acids with an estimated molecular mass of 22.88 and 27.94 kDa,respectively.The expression profiles of VpGSTS and VpGSTO responded to heavy metals and benzo[a]pyrene (B[a]P) cxposure were investigated by quantitative real-time RT-PCR.The expression of VpGSTS and VpGSTO were both rapidly up-regulated,however,they showed differential expression patterns to different toxicants.Cd displayed stronger induction of VpGSTS expression with an approximately 12-fold increase than that of VpGSTO with a maximum 6.4-fold rise.Cu exposure resulted in similar expression patterns for both VpGSTS and VpGSTO For B[a]P exposure,the maximum induction of VpGSTO was approximately two times higher than that of VpGSTS.Altogether,these findings implied the involvement of VpGSTS and VpGSTO in host antioxidant responses,and highlighted their potential as a biomarker to Cd and B[a]P exposure.

  15. Seasonal variation of benzo(a)pyrene in the Spanish airborne PM10. Multivariate linear regression model applied to estimate BaP concentrations

    International Nuclear Information System (INIS)

    The estimation of benzo(a)pyrene (BaP) concentrations in ambient air is very important from an environmental point of view especially with the introduction of the Directive 2004/107/EC and due to the carcinogenic character of this pollutant. A sampling campaign of particulate matter less or equal than 10 microns (PM10) carried out during 2008-2009 in four locations of Spain was collected to determine experimentally BaP concentrations by gas chromatography mass-spectrometry mass-spectrometry (GC-MS-MS). Multivariate linear regression models (MLRM) were used to predict BaP air concentrations in two sampling places, taking PM10 and meteorological variables as possible predictors. The model obtained with data from two sampling sites (all sites model) (R2 = 0.817, PRESS/SSY = 0.183) included the significant variables like PM10, temperature, solar radiation and wind speed and was internally and externally validated. The first validation was performed by cross validation and the last one by BaP concentrations from previous campaigns carried out in Zaragoza from 2001-2004. The proposed model constitutes a first approximation to estimate BaP concentrations in urban atmospheres with very good internal prediction (QCV2=0.813, PRESS/SSY = 0.187) and with the maximal external prediction for the 2001-2002 campaign (Qext2=0.679 and PRESS/SSY = 0.321) versus the 2001-2004 campaign (Qext2=0.551, PRESS/SSY = 0.449).

  16. Radiation results in IL-8 mediated intercellular signaling that increases adhesion between monocytic cells and aortic endothelium

    Science.gov (United States)

    Kucik, Dennis; Babitz, Stephen; Dunaway, Chad; Steele, Chad

    Epidemiological evidence has established terrestrial radiation exposure as a risk factor for cardiovascular disease. For example, a major side effect of therapeutic radiation, especially for breast and head-and-neck cancers, is atherosclerosis, which can result in stroke years after treatment. Similarly, atomic bomb survivors were significantly more likely to die of cardiovascular disease than their countrymen. Even radiation technologists, prior to 1950 (when regulations governing shielding and occupational exposure were less rigorous) had an increased risk of clinically significant atherosclerosis. We have recently shown that 600 MeV (56) Fe similarly exacerbates plaque formation in the apoE mouse atherosclerosis model at doses 4-7 fold lower than required for x-rays to produce a similar pro-atherogenic effect. This raises concern that exposure to cosmic radiation might pose a similar risk for astronauts. Because so little is known about the mechanism of pro-atherogenic radiation effects, however, the current strategy to minimize risk from terrestrial radiation sources is to limit exposure. For astronauts on deep space missions, exposure to a significant amount of radiation will be unavoidable. Therefore, an understanding of the mechanism of radiation-induced atherosclerosis will be essential in order to develop countermeasures. Radiation can cause increased adhesiveness of vascular endothelium, leading to inappropriate accumulation of monocytes and other white blood cells, which can initiate a self-perpetuating inflammatory response. This vascular inflammation is an early event in atherosclerosis that can eventually lead to clinically significant cardiovascular events such as myocardial infarction and stroke. We showed earlier that x-rays, (56) Fe, and (28) Si all accelerate development of atherosclerosis in the apoE -/- mouse model. We also demonstrated that both x-rays and heavy ions increase adhesion of monocytic cells to vascular human aortic endothelial

  17. Expression of putative expansin genes in phylloxera (Daktulosphaira vitifoliae Fitch) induced root galls of Vitis spp.

    OpenAIRE

    Lawo, N. C.; Griesser, M.; Forneck, A.

    2013-01-01

    Grape phylloxera (Daktulosphaira vitifoliae Fitch) is a serious global pest in viticulture. The insects are sedentary feeders and require a gall to feed and reproduce. The insects induce their feeding site within the meristematic zone of the root tip, where they stay attached, feeding both intra- and intercellularly, and causing damage by reducing plant vigour. Several changes in cell structure and composition, including increased cell division and tissue swelling close to the feeding site, c...

  18. Cold Ischemia Induces Isograft Arteriopathy, but Does Not Augment Allograft Arteriopathy in Non-Immunosuppressed Hosts

    OpenAIRE

    Furukawa, Yutaka; Libby, Peter; Stinn, Jennifer L.; Becker, Gerold; Mitchell, Richard N

    2002-01-01

    Prolonged cold ischemia has been suggested as a factor that will exacerbate later graft arterial disease (GAD), a major limiting factor for long-term transplant survival. We therefore examined the effects of cold ischemia on GAD as well as adhesion molecule and cytokine expression in murine cardiac grafts. Mild GAD developed in isografts undergoing 4-hour cold ischemia. Relative to control isografts, cold ischemia induced transiently enhanced endothelial expression of intercellular adhesion m...

  19. Versatility of Biofilm Matrix Molecules in Staphylococcus epidermidis Clinical Isolates and Importance of Polysaccharide Intercellular Adhesin Expression during High Shear Stress

    Science.gov (United States)

    Schaeffer, Carolyn R.; Hoang, Tra-My N.; Sudbeck, Craig M.; Alawi, Malik; Tolo, Isaiah E.; Robinson, D. Ashley; Horswill, Alexander R.; Rohde, Holger

    2016-01-01

    ABSTRACT Staphylococcus epidermidis is a leading cause of hospital-associated infections, including those of intravascular catheters, cerebrospinal fluid shunts, and orthopedic implants. Multiple biofilm matrix molecules with heterogeneous characteristics have been identified, including proteinaceous, polysaccharide, and nucleic acid factors. Two of the best-studied components in S. epidermidis include accumulation-associated protein (Aap) and polysaccharide intercellular adhesin (PIA), produced by the enzymatic products of the icaADBC operon. Biofilm composition varies by strain as well as environmental conditions, and strains producing PIA-mediated biofilms are more robust. Clinically, biofilm-mediated infections occur in a variety of anatomical sites with diverse physiological properties. To test the hypothesis that matrix composition exhibits niche specificity, biofilm-related genetic and physical properties were compared between S. epidermidis strains isolated from high-shear and low-shear environments. Among a collection of 105 clinical strains, significantly more isolates from high-shear environments carried the icaADBC operon than did those from low-shear settings (43.9% versus 22.9%, P 0.05). Additionally, a significantly greater number of high-shear isolates were capable of forming biofilm in vitro in a microtiter assay (82.5% versus 45.8%, P biofilm mechanisms. Sequencing of selected variants identified substitutions capable of enhancing biofilm formation in multiple genes, further highlighting the heterogeneity of S. epidermidis biofilm molecules and mechanisms. IMPORTANCE Staphylococcus epidermidis is a leading cause of infections related to biomaterials, mostly due to their ability to form biofilm. Biofilm accumulation mechanisms vary, including those that are dependent on specific proteins, environmental DNA (eDNA), or polysaccharide intercellular adhesin (PIA). We found that those isolates obtained from high-shear environments, such as the lumen

  20. Upregulation of Intercellular Adhesion Molecule 1 and Proinflammatory Cytokines by the Major Surface Proteins of Treponema maltophilum and Treponema lecithinolyticum, the Phylogenetic Group IV Oral Spirochetes Associated with Periodontitis and Endodontic Infections

    Science.gov (United States)

    Lee, Sung-Hoon; Kim, Kack-Kyun; Choi, Bong-Kyu

    2005-01-01

    Treponema maltophilum and Treponema lecithinolyticum belong to the group IV oral spirochetes and are associated with endodontic infections, as well as periodontitis. Recently, the genes encoding the major surface proteins (Msps) of these bacteria (MspA and MspTL, respectively) were cloned and sequenced. The amino acid sequences of these proteins showed significant similarity. In this study we analyzed the functional role of these homologous proteins in human monocytic THP-1 cells and primary cultured periodontal ligament (PDL) cells using recombinant proteins. The complete genes encoding MspA and MspTL without the signal sequence were cloned into Escherichia coli by using the expression vector pQE-30. Fusion proteins tagged with N-terminal hexahistidine (recombinant MspA [rMspA] and rMspTL) were obtained, and any possible contamination of the recombinant proteins with E. coli endotoxin was removed by using polymyxin B-agarose. Flow cytometry showed that rMspA and rMspTL upregulated the expression of intercellular adhesion molecule 1 (ICAM-1) in both THP-1 and PDL cells. Expression of proinflammatory cytokines, such as interleukin-6 (IL-6) and IL-8, was also induced significantly in both cell types by the Msps, as determined by reverse transcription-PCR and an enzyme-linked immunosorbent assay, whereas IL-1β synthesis could be detected only in the THP-1 cells. The upregulation of ICAM-1, IL-6, and IL-8 was completely inhibited by pretreating the cells with an NF-κB activation inhibitor, l-1-tosylamido-2-phenylethyl chloromethyl ketone. This suggests involvement of NF-κB activation. The increased ICAM-1 and IL-8 expression in the THP-1 cells obtained with rMsps was not inhibited in the presence of the IL-1 receptor antagonist (IL-1ra), a natural inhibitor of IL-1. Our results show that the Msps of the group IV oral spirochetes may play an important role in amplifying the local immune response by continuous inflammatory cell recruitment and retention at an

  1. Oxidative Damage to Nucleic Acids and Benzo(apyrene-7,8-diol-9,10-epoxide-DNA Adducts and Chromosomal Aberration in Children with Psoriasis Repeatedly Exposed to Crude Coal Tar Ointment and UV Radiation

    Directory of Open Access Journals (Sweden)

    Lenka Borska

    2014-01-01

    Full Text Available The paper presents a prospective cohort study. Observed group was formed of children with plaque psoriasis (n=19 treated by Goeckerman therapy (GT. The study describes adverse (side effects associated with application of GT (combined exposure of 3% crude coal tar ointment and UV radiation. After GT we found significantly increased markers of oxidative stress (8-hydroxy-2′-deoxyguanosine, 8-hydroxyguanosine, and 8-hydroxyguanine, significantly increased levels of benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE DNA adducts (BPDE-DNA, and significantly increased levels of total number of chromosomal aberrations in peripheral lymphocytes. We found significant relationship between (1 time of UV exposure and total number of aberrated cells and (2 daily topical application of 3% crude coal tar ointment (% of body surface and level of BPDE-DNA adducts. The findings indicated increased hazard of oxidative stress and genotoxic effects related to the treatment. However, it must be noted that the oxidized guanine species and BPDE-DNA adducts also reflect individual variations in metabolic enzyme activity (different extent of bioactivation of benzo[a]pyrene to BPDE and overall efficiency of DNA/RNA repair system. The study confirmed good effectiveness of the GT (significantly decreased PASI score.

  2. Serum levels of thrombomodulin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin in the acute phase of Plasmodium vivax malaria.

    Science.gov (United States)

    Ohnishi, K

    1999-02-01

    Elevated plasma or serum levels of thrombomodulin (TM), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin have been reported in several diseases. However, plasma or serum levels of TM, ICAM-1, VCAM-1, and E-selectin have not been investigated in the acute phase of Plasmodium vivax malaria. Serum TM, ICAM-1, VCAM-1, E-selectin, and creatinine levels were determined in six Japanese patients in the acute phase of vivax malaria and in seven healthy Japanese controls. Parasitemias of the peripheral blood were Fujirebio units/ml, 709 +/- 397 ng/ml, 2,112 +/- 782 ng/ml, and 99 +/- 28 ng/ml, respectively, and all were significantly greater than those in the controls (TM; P < 0.005, ICAM-1; P < 0.025, VCAM-1; P < 0.005, E-selectin; P < 0.025). However, no significant difference was identified between patients and controls for serum creatinine values. The serum levels of TM and VCAM-1 were not related to parasitemia. The elevation of serum TM levels suggests that endothelial cell damage occurs in the acute phase of vivax malaria.

  3. Expression and intercellular trafficking of the VP22 protein of CVI988/Rispens vaccine strain of Marek’s disease virus

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The viral protein 22 (VP22) in the tegument of Marek’s disease virus serotype 1 (MDV-1) plays an im-portant role in cell-to-cell spread and viral propagation. Antiserum against the carboxyl terminus of VP22 was prepared by immunizing mice with recombinant VP22 expressed in E. coli, and used to in-vestigate its expression in chicken embryo fibroblast (CEF) cells infected with different MDV-1 strains. At an infection dose of PFU=50, intercellular trafficking of the VP22 into the nuclei of the surrounding receipt cells was detected as early as 3 hours post infection. By 6 hours after infection (before viral plague formation), the protein was detected in the whole nuclei of the recipient cells with no difference among MDV-1 strains CVI988/Rispens, GA and RB1B. Intra-nuclear accumulation of the VP22 protein was further increased when the viral plagues started to form. These results indicate that, albeit the ex-istence of the 201TKSERT206 deletion, the VP22 of the CVI988/Rispens vaccine strain has also intercel-lular-trafficking function, which might serve as a potential alternative delivering protein instead of virulent strains VP22.

  4. FRET based quantification and screening technology platform for the interactions of leukocyte function-associated antigen-1 (LFA-1 with intercellular adhesion molecule-1 (ICAM-1.

    Directory of Open Access Journals (Sweden)

    Sandeep Chakraborty

    Full Text Available The interaction between leukocyte function-associated antigen-1(LFA-1 and intercellular adhesion molecule-1 (ICAM-1 plays a pivotal role in cellular adhesion including the extravasation and inflammatory response of leukocytes, and also in the formation of immunological synapse. However, irregular expressions of LFA-1 or ICAM-1 or both may lead to autoimmune diseases, metastasis cancer, etc. Thus, the LFA-1/ICAM-1 interaction may serve as a potential therapeutic target for the treatment of these diseases. Here, we developed one simple 'in solution' steady state fluorescence resonance energy transfer (FRET technique to obtain the dissociation constant (Kd of the interaction between LFA-1 and ICAM-1. Moreover, we developed the assay into a screening platform to identify peptides and small molecules that inhibit the LFA-1/ICAM-1 interaction. For the FRET pair, we used Alexa Fluor 488-LFA-1 conjugate as donor and Alexa Fluor 555-human recombinant ICAM-1 (D1-D2-Fc as acceptor. From our quantitative FRET analysis, the Kd between LFA-1 and D1-D2-Fc was determined to be 17.93±1.34 nM. Both the Kd determination and screening assay were performed in a 96-well plate platform, providing the opportunity to develop it into a high-throughput assay. This is the first reported work which applies FRET based technique to determine Kd as well as classifying inhibitors of the LFA-1/ICAM-1 interaction.

  5. Gap junctional intercellular communication as a biological "Rosetta stone" in understanding, in a systems biological manner, stem cell behavior, mechanisms of epigenetic toxicology, chemoprevention and chemotherapy.

    Science.gov (United States)

    Trosko, James E

    2007-08-01

    In spite of the early speculation by Loewenstein that one of the critical distinguishing phenotypes of cancers from normal cells was the dysfunction of gap junctional intercellular communication (GJIC), this hypothesis has not captured the attention of most birth defects and cancer researchers. Moreover, even with later demonstrations that factors that influence normal development and carcinogenesis by modulating GJIC, such as chemical teratogens and tumor-promoting chemicals, inflammatory factors, hormones and growth factors, antisense connexin genes, knockout mouse models, human inherited mutated connexin genes, si-connexin RNA, chemopreventive and chemotherapeutic chemicals, it is rare that one sees any reference to these studies by the mainstream investigators in these fields. Based on the assumption that the evolutionarily conserved connexin genes found in metazoans are needed for normal development and the maintenance of health and T. Dobzhansky's statement "Nothing in biology makes sense except in the light of evolution," a short review of the roles of endogenous and exogenous modulators of GJIC will be made in the context of the multistage, multimechanism process of carcinogenesis, the stem cell theory of carcinogenesis, the discovery and characterization of normal adult stem "cancer stem" cells and the observation that two distinct classes of GJIC-deficient cancer cells are known. The implications of these observations to a "systems biological" view of the role of gap junctions and the nutritional prevention and treatment of several chronic diseases and cancer will be discussed.

  6. Intercellular Adhesion-Dependent Cell Survival and ROCK-Regulated Actomyosin-Driven Forces Mediate Self-Formation of a Retinal Organoid

    Directory of Open Access Journals (Sweden)

    Albert Lowe

    2016-05-01

    Full Text Available In this study we dissected retinal organoid morphogenesis in human embryonic stem cell (hESC-derived cultures and established a convenient method for isolating large quantities of retinal organoids for modeling human retinal development and disease. Epithelialized cysts were generated via floating culture of clumps of Matrigel/hESCs. Upon spontaneous attachment and spreading of the cysts, patterned retinal monolayers with tight junctions formed. Dispase-mediated detachment of the monolayers and subsequent floating culture led to self-formation of retinal organoids comprising patterned neuroretina, ciliary margin, and retinal pigment epithelium. Intercellular adhesion-dependent cell survival and ROCK-regulated actomyosin-driven forces are required for the self-organization. Our data supports a hypothesis that newly specified neuroretina progenitors form characteristic structures in equilibrium through minimization of cell surface tension. In long-term culture, the retinal organoids autonomously generated stratified retinal tissues, including photoreceptors with ultrastructure of outer segments. Our system requires minimal manual manipulation, has been validated in two lines of human pluripotent stem cells, and provides insight into optic cup invagination in vivo.

  7. Neuropeptide Y, substance P, and human bone morphogenetic protein 2 stimulate human osteoblast osteogenic activity by enhancing gap junction intercellular communication

    Energy Technology Data Exchange (ETDEWEB)

    Ma, W.H.; Liu, Y.J.; Wang, W.; Zhang, Y.Z. [The Third Hospital of Hebei Medical University, The Provincial Key Laboratory for Orthopedic Biomechanics of Hebei, Shijiazhuang, Hebei Province (China)

    2015-02-13

    Bone homeostasis seems to be controlled by delicate and subtle “cross talk” between the nervous system and “osteo-neuromediators” that control bone remodeling. The purpose of this study was to evaluate the effect of interactions between neuropeptides and human bone morphogenetic protein 2 (hBMP2) on human osteoblasts. We also investigated the effects of neuropeptides and hBMP2 on gap junction intercellular communication (GJIC). Osteoblasts were treated with neuropeptide Y (NPY), substance P (SP), or hBMP2 at three concentrations. At various intervals after treatment, cell viability was measured by the MTT assay. In addition, cellular alkaline phosphatase (ALP) activity and osteocalcin were determined by colorimetric assay and radioimmunoassay, respectively. The effects of NPY, SP and hBMP on GJIC were determined by laser scanning confocal microscopy. The viability of cells treated with neuropeptides and hBMP2 increased significantly in a time-dependent manner, but was inversely associated with the concentration of the treatments. ALP activity and osteocalcin were both reduced in osteoblasts exposed to the combination of neuropeptides and hBMP2. The GJIC of osteoblasts was significantly increased by the neuropeptides and hBMP2. These results suggest that osteoblast activity is increased by neuropeptides and hBMP2 through increased GJIC. Identification of the GJIC-mediated signal transduction capable of modulating the cellular activities of bone cells represents a novel approach to studying the biology of skeletal innervation.

  8. Spatial and temporal scaling of intercellular CO2 concentration in a temperate rain forest dominated by Dacrydium cupressinum in New Zealand.

    Science.gov (United States)

    Tissue, David T; Barbour, Margaret M; Hunt, John E; Turnbull, Matthew H; Griffin, Kevin L; Walcroft, Adrian S; Whitehead, David

    2006-04-01

    Seven methods, including measurements of photosynthesis (A) and stomatal conductance (g(s)), carbon isotope discrimination, ecosystem CO2 and water vapour exchange using eddy covariance and the use of a multilayer canopy model and ecosystem Keeling plots, were employed to derive estimates of intercellular CO2 concentration (Ci) across a range of spatial and temporal scales in a low productivity rain forest ecosystem dominated by the conifer Dacrydium cupressinum Lamb. in New Zealand. Estimates of shoot and canopy Ci across temporal scales ranging from minutes to years were remarkably similar (range of 274-294 micromol mol(-1)). The gradual increase in shoot Ci with depth in the canopy was more likely attributable to decreases in A resulting from lower irradiance (Q) than to increases in g, due to changes in air saturation deficit (D). The lack of marked vertical gradients in A and g(s) at saturating Q through the canopy and the low seasonal variability in environmental conditions contributed to the efficacy of scaling Ci. However, the canopy Ci estimate calculated from the carbon isotope composition of respired ecosystem CO2 (delta13CR; 236 micromol mol(-1)) was much lower than other estimates of canopy Ci. Partitioning delta13CR into four components (soil, roots, litter and foliage) indicated root respiration as the dominant (> 50%) contributor to delta13CR. Variable time lags and differences in isotopic composition during photosynthesis and respiration make the direct estimation of canopy Ci from delta 13CR problematic.

  9. DNA adducts, benzo(a)pyrene monooxygenase activity, and lysosomal membrane stability in Mytilus galloprovincialis from different areas in Taranto coastal waters (Italy)

    International Nuclear Information System (INIS)

    The aim of this study was to investigate the impact of environmental pollution at different stations along the Taranto coastline (Ionian Sea, Puglia, Italy) using several biomarkers of exposure and the effect on mussels, Mytilus galloprovincialis, collected in October 2001 and October 2002. Five sampling sites were compared with a 'cleaner' reference site in the Aeronautics Area. In this study we also investigated the differences between adduct levels in gills and digestive gland. This Taranto area is the most significant industrial settlement on the Ionian Sea known to be contaminated by polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls, heavy metals, etc. Exposure to PAHs was evaluated by measuring DNA adduct levels and benzo(a)pyrene monooxygenase activity (B(a)PMO); DNA adducts were analyzed by 32P-postlabeling with nuclease P1 enhancement in both gills and digestive glands to evaluate differences between DNA adduct levels in the two tissues. B(a)PMO was assayed in the microsomal fraction of the digestive glands as a result of the high expression of P450-metabolizing enzymes in this tissue. Lysosomal membrane stability, a potential biomarker of anthropogenic stress, was also evaluated in the digestive glands of mussels, by measuring the latent activity of β-N-acetylhexosaminidase. Induction of DNA adducts was evident in both tissues, although the results revealed large tissue differences in DNA adduct formation. In fact, gills showed higher DNA adduct levels than did digestive gland. No significant differences were found in DNA adduct levels over time, with both tissues providing similar results in both years. DNA adduct levels were correlated with B(a)PMO activity in digestive gland in both years (r=0.60 in 2001; r=0.73 in 2002). Increases were observed in B(a)PMO activity and DNA adduct levels at different stations; no statistical difference was observed in B(a)PMO activity over the two monitoring campaigns. The membrane labilization period

  10. Degradation of PAHs in soil by Lasiodiplodia theobromae and enhanced benzo[a]pyrene degradation by the addition of Tween-80.

    Science.gov (United States)

    Wang, Cuiping; Liu, Haibin; Li, Jing; Sun, Hongwen

    2014-09-01

    Benzo[a]pyrene (BaP), a five-ring polycyclic aromatic hydrocarbon (PAH), which has carcinogenic potency, is highly recalcitrant and resistant to microbial degradation. A novel fungus, Lasiodiplodia theobromae (L. theobromae), which can degrade BaP as a sole carbon source in liquid, was isolated in our laboratory. To prompt the further application of L. theobromae in remediation of sites polluted by BaP and other PAHs, the present study was targeted toward the removal of BaP and PAHs from soil by L. theobromae. The degradation of BaP by L. theobromae was studied using a soil spiked with 50 mg/kg BaP. L. theobromae could remove 32.1 % of the BaP after 35 days of cultivation. Phenanthrene (PHE) inhibited BaP degradation as a competitive substrate. The tested surfactants enhanced BaP degradation in soil by different extents, and a removal rate of 92.1 % was achieved at a Tween-80 (TW-80) concentration of 5 g/kg. It was revealed that TW-80 could not only enhance BaP bioavailability by increasing its aqueous solubility and decreasing the size of its colloid particles but also increase enzyme secretion from L. theobromae and the population of L. theobromae. Moreover, ergosterol content together with the biomass C indicated the increase in L. theobromae biomass during the BaP biodegradation process in soils. Finally, a soil from a historically PAH-contaminated field at Beijing Coking Plant in China was tested to assess the feasibility of applying L. theobromae in the remediation of polluted sites. The total removal rate of PAHs by L. theobromae was 53.3 %, which is 13.1 % higher than that by Phanerochaete chrysosporium (P. chrysosporium), an effective PAH degrader. The addition of TW-80 to the field soil further enhanced PAH degradation to 73.2 %. Hence, L. theobromae is a promising novel strain to be implemented in the remediation of soil polluted by PAHs. PMID:24878554

  11. Low-Level Laser Therapy Attenuates LPS-Induced Rats Mastitis by Inhibiting Polymorphonuclear Neutrophil Adhesion

    OpenAIRE

    Wang, Yueqiang; HE, Xianjing; HAO, Dandan; Yu, Debin; LIANG, Jianbin; QU, Yanpeng; Sun, Dongbo; Yang, Bin; YANG, Keli; Wu, Rui; WANG, Jianfa

    2014-01-01

    ABSTRACT The aim of this study was to investigate the effects of low-level laser therapy (LLLT) on a rat model of lipopolysaccharide (LPS)-induced mastitis and its underlying molecular mechanisms. The rat model of mastitis was induced by inoculation of LPS through the canals of the mammary gland. The results showed that LPS-induced secretion of IL-1β and IL-8 significantly decreased after LLLT (650 nm, 2.5 mW, 30 mW/cm2). LLLT also inhibited intercellular adhesion molecule-1 (ICAM-1) expressi...

  12. Intercellular Cell Adhesion Molecule-1, Vascular Cell Adhesion Molecule-1, and Regulated on Activation Normal T Cell Expressed and Secreted Are Expressed by Human Breast Carcinoma Cells and Support Eosinophil Adhesion and Activation

    OpenAIRE

    Ali, Shahina; Kaur, Jaswinder; Patel, Kamala D.

    2000-01-01

    Eosinophils are usually associated with parasitic and allergic diseases; however, eosinophilia is also observed in several types of human tumors, including breast carcinomas. In this study we examined several human breast carcinoma cell lines for adhesion molecule expression and the ability to bind and activate eosinophils. MDA-MB-435S and MDA-MB-468 cells constitutively expressed both intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) and this expressio...

  13. Mutation of sepJ reduces the intercellular signal range of a hetN-dependent paracrine signal, but not of a patS-dependent signal, in the filamentous cyanobacterium Anabaena sp. strain PCC 7120.

    Science.gov (United States)

    Rivers, Orion S; Videau, Patrick; Callahan, Sean M

    2014-12-01

    Formation and maintenance of a periodic pattern of nitrogen-fixing cells called heterocysts by the filamentous cyanobacterium Anabaena sp. strain PCC 7120 is dependent on regulators encoded by patS and hetN. In this study, genetic mosaic filaments that consisted of cells engineered to produce one of the developmental regulators flanked by target cells capable of reporting the activity of the developmental regulator were used to investigate the intercellular movement of patS- and hetN-dependent activity. We provide evidence that hetN encodes a paracrine signal with a signal range of several cells. The signal that moved between cells did not include the C-terminus of the annotated HetN protein as indicated by similar signal ranges from source cells expressing either hetN-YFP or hetN alone, despite a lack of intercellular exchange of the HetN-YFP fusion protein. Deletion of sepJ, which has been shown to encode a component of intercellular channels, caused a significant decrease in the signal range of hetN expressed from source cells but not of patS. These results are consistent with symplastic transport of a paracrine hetN-dependent signal between vegetative cells of Anabaena.

  14. Effect of deficient ERCC2/XPD gene on the repair of DNA damage induced by benzo[a]pyrene%ERCC2/XPD基因缺失对苯并[a]芘所致DNA损伤修复的影响

    Institute of Scientific and Technical Information of China (English)

    肖莎; 刘秋芳; 徐韬钧; 关阳阳; 靳翠红; 李丹丹; 逯晓波

    2012-01-01

    目的:探讨核苷酸切除修复交叉互补基因2 (excision repair cross complementation group 2/Xeroderma pigmentosum D,ERCC2/XPD)在苯并[a]芘所诱导的细胞DNA损伤与修复过程中的作用.方法:应用中国仓鼠卵巢细胞系CHO野生型AA8和ERCC2表达缺失型UV5作为细胞对照模型,MTT法比较两种细胞经苯并[a]芘处理后细胞抑制率的差别;彗星试验和Rad51免疫荧光试验检测不同浓度苯并[a]芘处理及修复24 h后细胞DNA损伤修复的情况.结果:与野生型AA8细胞相比,UV5细胞对苯并[a]芘所致损伤更加敏感,细胞存活率降低(P<0.05).彗星试验和Rad51免疫荧光试验结果显示,UV5细胞由于缺失ERCC2/XPD基因,修复苯并[a]芘所致DNA损伤能力降低(P<0.05).结论:ERCC2/XPD蛋白在核苷酸切除修复中发挥解旋作用,对苯并[a]芘所致DNA损伤修复至关重要.%OBJECTIVE: To investigate ERCC2/XPD (excision repair cross complementation group 2/Xeroderma pigmentosum D) function in the repair of DNA damage induced by benzo[a]pyrene. METHODS: China hamster ovary (CHO) cell line including wild type AA8 and ERCC2/XPD defective mutant UV5, was set up as a cell contrast model. DNA damage levels at different time points after benzo[a]pyrene treatment were evaluated by MTT cell inhibition assay, modified comet assay and Rad51 immunofluorescence test. RESULTS: UV5 was more sensitive to benzo[a]pyrene when compared with AA8. The DNA damage caused by benzo[a]pyrene was repaired by AA8 but not by UV5. CONCLUSION: ERCC2/XPD, as an important helicase in nucleotide excision repair, could play a critical role in repairing DNA damage induced by benzo[a]pyrene.

  15. Characterization of a distinct population of circulating human non-adherent endothelial forming cells and their recruitment via intercellular adhesion molecule-3.

    Directory of Open Access Journals (Sweden)

    Sarah L Appleby

    Full Text Available Circulating vascular progenitor cells contribute to the pathological vasculogenesis of cancer whilst on the other hand offer much promise in therapeutic revascularization in post-occlusion intervention in cardiovascular disease. However, their characterization has been hampered by the many variables to produce them as well as their described phenotypic and functional heterogeneity. Herein we have isolated, enriched for and then characterized a human umbilical cord blood derived CD133(+ population of non-adherent endothelial forming cells (naEFCs which expressed the hematopoietic progenitor cell markers (CD133, CD34, CD117, CD90 and CD38 together with mature endothelial cell markers (VEGFR2, CD144 and CD31. These cells also expressed low levels of CD45 but did not express the lymphoid markers (CD3, CD4, CD8 or myeloid markers (CD11b and CD14 which distinguishes them from 'early' endothelial progenitor cells (EPCs. Functional studies demonstrated that these naEFCs (i bound Ulex europaeus lectin, (ii demonstrated acetylated-low density lipoprotein uptake, (iii increased vascular cell adhesion molecule (VCAM-1 surface expression in response to tumor necrosis factor and (iv in co-culture with mature endothelial cells increased the number of tubes, tubule branching and loops in a 3-dimensional in vitro matrix. More importantly, naEFCs placed in vivo generated new lumen containing vasculature lined by CD144 expressing human endothelial cells (ECs. Extensive genomic and proteomic analyses of the naEFCs showed that intercellular adhesion molecule (ICAM-3 is expressed on their cell surface but not on mature endothelial cells. Furthermore, functional analysis demonstrated that ICAM-3 mediated the rolling and adhesive events of the naEFCs under shear stress. We suggest that the distinct population of naEFCs identified and characterized here represents a new valuable therapeutic target to control aberrant vasculogenesis.

  16. Maternal serum uric acid concentration is associated with the expression of tumour necrosis factor-α and intercellular adhesion molecule-1 in patients with preeclampsia.

    Science.gov (United States)

    Zhao, J; Zheng, D-Y; Yang, J-M; Wang, M; Zhang, X-T; Sun, L; Yun, X-G

    2016-07-01

    We aimed to investigate whether there is a correlation between elevated serum uric acid (SUA) concentration and endothelial inflammatory response in women with preeclampsia (PE). On the basis of clinical and laboratory findings, patients were assigned to three groups: normal blood pressure (Control (Con)), gestational hypertension (GH) and PE (n=50 in each group). SUA concentration was measured by spectrophotometry, and serum tumour necrosis factor-α (TNF-α) and intercellular adhesion molecule-1 (ICAM-1) levels were measured by enzyme-linked immunosorbent assay. Western blotting and immunohistochemical staining were also used to detect the changes in TNF-α and ICAM-1 expression in subcutaneous fat tissue. PE patients showed significantly higher systolic and diastolic blood pressures compared with Con and GH pregnant women (P=0.02 and P=0.02, respectively). The changes of body mass index (ΔBMI) before and after pregnancy and 24-h urine protein were significantly different among the three groups (P<0.001). Maternal SUA, TNF-α and soluble ICAM-1 (sICAM-1) levels were significantly increased in the patients with PE (P<0.05) compared with the other two groups. Scatterplot analysis revealed that elevated SUA concentration positively correlated with TNF-α and sICAM-1 in pregnant women. Moreover, vessels in subcutaneous fat tissues of preeclamptic patients showed intense TNF-α and ICAM-1 staining compared with Con and GH patients. The results support that, to a certain extent, elevated SUA concentration is significantly associated with inflammation of maternal systemic vasculature as indicated by increased TNF-α and ICAM-1 expression in women with PE. PMID:26511169

  17. The Serum Changes of Neuron-Specific Enolase and Intercellular Adhesion Molecule-1 in Patients With Diffuse Axonal Injury Following Progesterone Administration: A Randomized Clinical Trial

    Science.gov (United States)

    Shahrokhi, Nader; Soltani, Zahra; Khaksari, Mohammad; Karamouzian, Saeid; Mofid, Behshad; Asadikaram, Gholamreza

    2016-01-01

    Background Improvement of neurologic outcome in progesterone-administered patients with diffuse axonal injury (DAI) has been found in a recent study. Also, there has been interest in the importance of serum parameters as predictors of outcome in traumatic brain injury. Objectives The aim of this study was to examine the effect of progesterone administration on serum levels of neuron-specific enolase (NSE), and intercellular adhesion molecule-1 (ICAM-1) in clinical DAI. Patients and Methods In this study, the serum levels of ICAM-1 and NSE of 32 male DAI patients (18 - 60 years of age, a Glasgow coma scale of 12 or less, and admitted within 4 hours after injury) who were randomized for a controlled phase II trial of progesterone were analyzed. The analysis was performed between the control and progesterone groups at admission time, and 24 hours and six days after DAI, respectively. Results A reduction in the serum level of ICAM-1 was noticed in the progesterone group 24 hours after the injury (P < 0.05). There was no significant difference in the serum level of NSE between the study groups during evaluation. At 24 hours after the injury, the level of ICAM-1 in the control group was higher than that at admission time (P < 0.05). The lowest level of NSE in the two groups was seen six days after DAI (P < 0.01). Conclusions In summary, progesterone administration reduced serum ICAM-1, and whereby may attenuate blood brain barrier disruption, the latter needs further investigation for confirmation.

  18. Androgen receptor in Sertoli cells regulates DNA double-strand break repair and chromosomal synapsis of spermatocytes partially through intercellular EGF-EGFR signaling.

    Science.gov (United States)

    Chen, Su-Ren; Hao, Xiao-Xia; Zhang, Yan; Deng, Shou-Long; Wang, Zhi-Peng; Wang, Yu-Qian; Wang, Xiu-Xia; Liu, Yi-Xun

    2016-04-01

    Spermatogenesis does not progress beyond the pachytene stages of meiosis in Sertoli cell-specific AR knockout (SCARKO) mice. However, further evidence of meiotic arrest and underlying paracrine signals in SCARKO testes is still lacking. We utilized co-immunostaining of meiotic surface spreads to examine the key events during meiotic prophase I. SCARKO spermatocytes exhibited a failure in chromosomal synapsis observed by SCP1/SCP3 double-staining and CREST foci quantification. In addition, DNA double-strand breaks (DSBs) were formed but were not repaired in the mutant spermatocytes, as revealed by γ-H2AX staining and DNA-dependent protein kinase (DNA-PK) activity examination. The later stages of DSB repair, such as the accumulation of the RAD51 strand exchange protein and the localization of mismatch repair protein MLH1, were correspondingly altered in SCARKO spermatocytes. Notably, the expression of factors that guide RAD51 loading onto sites of DSBs, including TEX15, BRCA1/2 and PALB2, was severely impaired when either AR was down-regulated or EGF was up-regulated. We observed that some ligands in the epidermal growth factor (EGF) family were over-expressed in SCARKO Sertoli cells and that some receptors in the EGF receptor (EGFR) family were ectopically activated in the mutant spermatocytes. When EGF-EGFR signaling was repressed to approximately normal by the specific inhibitor AG1478 in the cultured SCARKO testis tissues, the arrested meiosis was partially rescued, and functional haploid cells were generated. Based on these data, we propose that AR in Sertoli cells regulates DSB repair and chromosomal synapsis of spermatocytes partially through proper intercellular EGF-EGFR signaling.

  19. Interaction between Endothelial Protein C Receptor and Intercellular Adhesion Molecule 1 to Mediate Binding of Plasmodium falciparum-Infected Erythrocytes to Endothelial Cells

    Science.gov (United States)

    Avril, Marion; Bernabeu, Maria; Benjamin, Maxwell; Brazier, Andrew Jay

    2016-01-01

    ABSTRACT Intercellular adhesion molecule 1 (ICAM-1) and the endothelial protein C receptor (EPCR) are candidate receptors for the deadly complication cerebral malaria. However, it remains unclear if Plasmodium falciparum parasites with dual binding specificity are involved in cytoadhesion or different parasite subpopulations bind in brain microvessels. Here, we investigated this issue by studying different subtypes of ICAM-1-binding parasite lines. We show that two parasite lines expressing domain cassette 13 (DC13) of the P. falciparum erythrocyte membrane protein 1 (PfEMP1) family have dual binding specificity for EPCR and ICAM-1 and further mapped ICAM-1 binding to the first DBLβ domain following the PfEMP1 head structure in both proteins. As PfEMP1 head structures have diverged between group A (EPCR binders) and groups B and C (CD36 binders), we also investigated how ICAM-1-binding parasites with different coreceptor binding traits influence P. falciparum-infected erythrocyte binding to endothelial cells. Whereas levels of binding to tumor necrosis factor alpha (TNF-α)-stimulated endothelial cells from the lung and brain by all ICAM-1-binding parasite lines increased, group A (EPCR and ICAM-1) was less dependent than group B (CD36 and ICAM-1) on ICAM-1 upregulation. Furthermore, both group A DC13 parasite lines had higher binding levels to brain endothelial cells (a microvascular niche with limited CD36 expression). This study shows that ICAM-1 is a coreceptor for a subset of EPCR-binding parasites and provides the first evidence of how EPCR and ICAM-1 interact to mediate parasite binding to both resting and TNF-α-activated primary brain and lung endothelial cells. PMID:27406562

  20. The Value of the Soluable Intercellular Adhesion Molecule-1 Levelsin Matermal Serum for Determination of Occult Chorioamnionitis in Premature Rupture of Membranes

    Institute of Scientific and Technical Information of China (English)

    邹丽; 张会军; 祝建芳; 朱剑文

    2004-01-01

    To compare the diagnostic value of soluble intercellular adhesion molecule 1 (sICAM-1)with that of c-reactive protein (CRP) for detecting chorioamnionitis (CAM) in serum of women with premature rupture of membranes (PROM), 55 pregnant women with PROM, including 18pregnant women with preterm premature rupture of membranes (PPROM) and 20 normal pregnant women at term (TPROM) were studied. Maternal serum were measured by Sandwish enzymelinked immunoabsorbent assay (ELISA) for sICAM. CAM was histologically confirmed after delivery. The results revealed that (1) maternal serum levels of sICAM-1 and CRP were significantly higher in women with PROM than those without it; (2) maternal serum levels of sICAM-1 and CRP were significantly higher in women with CAM than those without it; (3) serum levels of sICAM-1 in PPROM women were similar to those in TPROM women, whereas serum levels of CRP in PPROM women were significantly higher than those in TPROM women; (4) the sensitivity,specificity, positive predictive value, negative predictive value, Kappa index and area under receiver operating characteristic (ROC) curve of maternal serum sICAM-1 (cutoff 104.7 ng/ml) and CRP (cutoff 1.03 mg/dl) for diagnosing CAM were 100 %, 91.2 %, 87.5 %, 100 %, 0.20, 0.995and 81.0 %, 73.5 %, 65.4 %, 86.2 %, 0.13, 0. 811, respectively; (5) among the mild histological CAM group, severe histological CAM group and clinical CAM group, the difference in maternal serum levels of sICAM-1 were significantly (P<0. 001), with the order of concentration from high level to low level corresponding to the severity of CAM. It is concluded that maternal serum level of ICAM-1 is superior to that of CRP as biomarker for diagnosing intraamniotic infection in pregnant women with PROM.

  1. Breast cancer cells compete with hematopoietic stem and progenitor cells for intercellular adhesion molecule 1-mediated binding to the bone marrow microenvironment.

    Science.gov (United States)

    Dhawan, Abhishek; Friedrichs, Jens; Bonin, Malte von; Bejestani, Elham Peshali; Werner, Carsten; Wobus, Manja; Chavakis, Triantafyllos; Bornhäuser, Martin

    2016-08-01

    Adhesion-based cellular interactions involved in breast cancer metastasis to the bone marrow remain elusive. We identified that breast cancer cells directly compete with hematopoietic stem and progenitor cells (HSPCs) for retention in the bone marrow microenvironment. To this end, we established two models of competitive cell adhesion-simultaneous and sequential-to study a potential competition for homing to the niche and displacement of the endogenous HSPCs upon invasion by tumor cells. In both models, breast cancer cells but not non-tumorigenic cells competitively reduced adhesion of HSPCs to bone marrow-derived mesenchymal stromal cells (MSCs) in a tumor cell number-dependent manner. Higher adhesive force between breast cancer cells and MSCs, as compared with HSPCs, assessed by quantitative atomic force microscopy-based single-cell force spectroscopy could partially account for tumor cell mediated reduction in HSPC adhesion to MSCs. Genetic inactivation and blockade studies revealed that homophilic interactions between intercellular adhesion molecule 1 (ICAM-1) expressed on tumor cells and MSCs, respectively, regulate the competition between tumor cells and HSPCs for binding to MSCs. Moreover, tumor cell-secreted soluble ICAM-1(sICAM-1) also impaired HSPC adhesion via blocking CD18-ICAM-1 binding between HSPCs and MSCs. Xenotransplantation studies in NOD.Cg-Prkdc(scid) Il2rg(tm1Wjl)/SzJ mice revealed reduction of human HSPCs in the bone marrow via metastatic breast cancer cells. These findings point to a direct competitive interaction between disseminated breast cancer cells and HSPCs within the bone marrow micro environment. This interaction might also have implications on niche-based tumor support. Therefore, targeting this cross talk may represent a novel therapeutic strategy. PMID:27207667

  2. Involvement of a putative intercellular signal-recognizing G protein-coupled receptor in the engulfment of Salmonella by the protozoan Tetrahymena

    Directory of Open Access Journals (Sweden)

    P.N. Agbedanu

    2013-07-01

    Full Text Available In an effort to investigate the molecular basis of protozoa engulfment-mediated hypervirulence of Salmonella in cattle, we evaluated protozoan G protein-coupled receptors (GPCRs as transducers of Salmonella engulfment by the model protozoan Tetrahymena. Our laboratory previously demonstrated that non-pathogenic protozoa (including Tetrahymena engulf Salmonella and then exacerbate its virulence in cattle, but the mechanistic details of the phenomenon are not fully understood. GPCRs were investigated since these receptors facilitate phagocytosis of particulates by Tetrahymena, and a GPCR apparently modulates bacterial engulfment for the pathogenic protozoan Entamoeba histolytica. A database search identified three putative Tetrahymena GPCRs, based on sequence homologies and predicted transmembrane domains, that were the focus of this study. Salmonella engulfment by Tetrahymena was assessed in the presence of suramin, a non-specific GPCR inhibitor. Salmonella engulfment was also assessed in Tetrahymena in which expression of putative GPCRs was knocked-down using RNAi. A candidate GPCR was then expressed in a heterologous yeast expression system for further characterization. Our results revealed that Tetrahymena were less efficient at engulfing Salmonella in the presence of suramin. Engulfment was reduced concordantly with a reduction in the density of protozoa. RNAi-based studies revealed that knock-down of one the Tetrahymena GPCRs caused diminished engulfment of Salmonella. Tetrahymena lysates activated this receptor in the heterologous expression system. These data demonstrate that the Tetrahymena receptor is a putative GPCR that facilitates bacterial engulfment by Tetrahymena. Activation of the putative GPCR seemed to be related to protozoan cell density, suggesting that its cognate ligand is an intercellular signaling molecule.

  3. Study on the serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) in patients with Helicobacter pylori Infection

    Institute of Scientific and Technical Information of China (English)

    吴勤动; 朱永良; 石益海

    2002-01-01

    Objective: To evaluate the interaction between serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) and Helicobacter pylori (H. pylori) infection in patients with chronic gastritis and peptic ulcer. Methods: The serum levels of sICAM-1 in 205 patients with chronic gastric diseases were detected by ELISA method and the status of H. pylori was determined by histologic examination, RUT, 14C - UBT, and serology. The sera obtained from 18 healthy volunteers served as controls. Results: The serum levels of sICAM-1 were significantly higher in patients with H. pylori positive than those of H. pylori negative (889.43±32.52 ng/ml vs. 747.07±30.45 ng/ml, P<0.05). The serum levels of sICAM-1 in patients with mild, moderate and severe infection of H. pylori were 841.68±72.36 ng/ml, 905.43±37.59 ng/ml and 1012.54±49.34 ng/ml,respectively (P<0.05). The serum levels of sICAM-1 proved to be significantly correlated with the density of H. pylori colonization in gastric mucosa (rs =0.316, P<0.001). The serum levels of sICAM-1 in patients with chronic gastritis and peptic ulcer were significantly higher than those in healthy controls (P<0.05). Conclusions: These results indicated that H. pylori infection up-regulates the expression of sICAM-1.

  4. Study on the serum levels of soluble intercellular adhesion molecule—1(slCAM—1) in patients with Helicobacter pylori Infection

    Institute of Scientific and Technical Information of China (English)

    吴勤动; 石益海; 等

    2002-01-01

    Objective:To evaluate the interaction between serum levels of soluble intercellular adhesion molecule-1(sICAM-1) and Helicobacter pylori(H.pylori) infection in patients with chronic gastritis and peptic ulcer.Methods:The serum levels of sICAM-1 in 205 patients with chronic gastric diseases were detected by ELISA method and the status of H.pylori was determined by histologic examination.RUT,14C=UBT,and serology,Ther sera obtained from 18 healthy volunteers served as controls,Results:The serum lervels of sICAM-1 were significantly higher in patients with H.pylori positive than those of H.pylori negative(889.43±32.52ng/mlvs,747.07±30.45ng/ml,P<0.05),The serum levels of sICAM-1 in patients with mild,moderate and severe infection of H.pylori were 841.68±72.36ng/ml,905.43±37.59ng/ml and 1012.54±49.34ng/ml,respectively(P<0.05),The serum levels of sICAM-1 proved to be significantly correlated with the density of H.pylori colonization in gastric mucosa(rs=0.316,P<0.001),The serum levels of sICAM-1 in patients with chronic gastritis and peptic ulcer were significantly higher than those in healthy controls(P<0.05).Conclusions:These results indicated that H.pylori infection up-regulates the expression of sICAM-1.

  5. Benzo pyrene-induced DNA adducts and gene expression profiles in target and non-target organs for carcinogenesis in mice

    OpenAIRE

    Zuo, Jie; Brewer, Daniel S; Arlt, Volker M.; Colin S. Cooper; Phillips, David H.

    2014-01-01

    Background Gene expression changes induced by carcinogens may identify differences in molecular function between target and non-target organs. Target organs for benzo[a]pyrene (BaP) carcinogenicity in mice (lung, spleen and forestomach) and three non-target organs (liver, colon and glandular stomach) were investigated for DNA adducts by 32P-postlabelling, for gene expression changes by cDNA microarray and for miRNA expression changes by miRNA microarray after exposure of animals to BaP. Resul...

  6. Exosomes for Intramyocardial Intercellular Communication

    OpenAIRE

    Elisabetta Cervio; Lucio Barile; Tiziano Moccetti; Giuseppe Vassalli

    2015-01-01

    Cross-talk between different cell types plays central roles both in cardiac homeostasis and in adaptive responses of the heart to stress. Cardiomyocytes (CMs) send biological messages to the other cell types present in the heart including endothelial cells (ECs) and fibroblasts. In turn, CMs receive messages from these cells. Recent evidence has now established that exosomes, nanosized secreted extracellular vesicles, are crucial mediators of such messages. CMs, ECs, cardiac fibroblasts, and ...

  7. Comparison of determining benzo(a)pyrene in vegetable oil by two methods%植物油中苯并(a)芘的检测方法比较研究

    Institute of Scientific and Technical Information of China (English)

    马素换; 汪学德; 刘兵戈

    2014-01-01

    比较高效液相色谱法和气相色谱-质谱联用法测定植物油中苯并(a)芘含量。结果表明,两种方法均采用中性氧化铝固相萃取柱净化油样,平均回收率均大于75%,相对标准偏差均小于8%,检出限分别为0.12μg / kg 和0.40μg / kg,均能满足测定要求。相对来说,高效液相色谱法前处理简便,峰形基线平稳,检出限低,回收率高,更适于植物油中苯并(a)芘含量的测定。%The determinations of benzo(a)pyrene in vegetable oil by high performance liquid chromatog-raphy( HPLC) and gas chromatography - mass spectrometry ( GC - MS) were compared. The results showed that the commercial neutral alumina solid - phase extraction column was employed to purify oil sample by two methods. The average recovery rates and relative standard deviations of two methods were all above 75% and below 8% respectively, and the limits of detection of two methods were 0. 12 μg / kg and 0. 40 μg / kg respectively, which could satisfy the measurement requirements. Relatively, HPLC method had the items of simple pretreatment, smooth baseline of peaks, low limit of detection and high recovery rate, which was more suitable for the determination of benzo(a)pyrene content of vegetable oil.

  8. Expression of inflammation related factors iNOS and ICAM-1 in endothelial cells induced by C-reactive protein

    OpenAIRE

    Song, Xu-Dong; Chen, Ai-Hua; He, Fei; Li, Zhi-Liang; Ying-feng LIU

    2011-01-01

    Objective To investigate the expression of inducible nitric oxide synthase(iNOS) and intercellular cell adhesion molecule-1(ICAM-1) in endothelial cells induced by C-reactive protein(CRP) and its corresponding mechanisms.Methods Human umbilical cord vein endothelial cells(HUVEC) were treated with different concentrations of CRP or with phosphate buffered solution as control,and RT-PCR was used for measurement of the expression of ICAM-1 mRNA induced by CRP in HUVECs.HUVEC were treated with CR...

  9. Study on the shape, phenotype and intercellular communication of chondrocyte%软骨细胞形态、表型与胞间通讯的研究

    Institute of Scientific and Technical Information of China (English)

    张文涛; 卢世璧

    2004-01-01

    BACKGROUND: The chondrocytes cultured in vitro will grow in a thin layer and lose their pheootype, assuming fibroblast. There is no report about the relationship between the phenotype and intercellular communication of chondrocytes.OBJECTIVE: To study the proliferation, matrix synthesis, relationship between fluorescence stain intake and gap junction of various form chondrocytes cultured in vitro.DESIGN: An experimental study based on diagnosis was conducted.SETTING and PARTICIPANTS: The experiment was conducted in the Institute of Orthopaedics, and Institute of Basic Sciences, General Hospital of PLA. The subjects were rabbit joint cartilages and human femoral head cartilages.INTERVENTIONS: Rabbit chondrocytes cultured in vitro were stained with hematoxylin-eosin(HE) and light green-safranin O respectively. The chondrocyte' s size was measured with microscope and the intracellular fluorescence intensity was measured with confocal laser microscope. The fluorescence stain in chondrocyte was quenched with laser.MAIN OUTCOME MEASURES: Appearance, size and intracellular fluorescence intensity of chondrocytes.RESULTS: The chondrocytes became larger and lost their spherical form.Then their proliferation was accelerated. The average projection area was 1755.1 μm2 with the difference of 50 times. The matrix synthesis and gap junction disappeared. The intake of CFDA-AM increased in spherical chondrocytes(average 2057/30 cells) compared with the decreased intake in flat chondrocytes(average 80/30 cells) . There was intercellular communication in spherical rabbit chondrocytes in vitro and human chondrocytes in lacuna of cartilage germinal layer.CONCLUSION: There are certain relationships among the density, form,phenotype and gap junction in chondrocytes. The phenotype may be determined by chondrocytes form.%背景:在体外培养时软骨细胞会像成纤维细胞样成片生长并失去表型,软骨细胞胞间通讯与细胞表型的关系尚无报告.目的:了解体外

  10. MicroRNA-155 Modulates the Pathogen Binding Ability of Dendritic Cells (DCs) by Down-regulation of DC-specific Intercellular Adhesion Molecule-3 Grabbing Non-integrin (DC-SIGN)*

    OpenAIRE

    Martinez-Nunez, Rocio T.; Louafi, Fethi; Friedmann, Peter S.; Sanchez-Elsner, Tilman

    2009-01-01

    MicroRNA-155 (miR-155) has been involved in the response to inflammation in macrophages and lymphocytes. Here we show how miR-155 participates in the maturation of human dendritic cells (DC) and modulates pathogen binding by down-regulating DC-specific intercellular adhesion molecule-3 grabbing non-integrin (DC-SIGN), after directly targeting the transcription factor PU.1. During the maturation of DCs, miR-155 increases up to 130-fold, whereas PU.1 protein levels decrease accordingly. We esta...

  11. Cell Death Mechanisms Induced by Cytotoxic Lymphocytes

    Institute of Scientific and Technical Information of China (English)

    Ch(a)vez-Gal(a)n L; Arenas-Del Angel MC; Zenteno E; Ch(a)vez R; Lascurain R

    2009-01-01

    One of the functions of the immune system is to recognize and destroy abnormal or infected cells to maintain homeostasis. This is accomplished by cytotoxic lymphocytes. Cytotoxicity is a highly organized multifactor process. Here, we reviewed the apoptosis pathways induced by the two main cytotoxic lymphocyte subsets, natural killer (NK) cells and CD8+T cells. In base to recent experimental evidence, we reviewed NK receptors involved in recognition of target-cell, as well as lytic molecules such as perforin, granzymes-A and -B, and granulysin. In addition, we reviewed the Fas-FasL intercellular linkage mediated pathway, and briefly the cross-linking of tumor necrosis factor (TNF) and TNF receptor pathway. We discussed three models of possible molecular interaction between lyric molecules from effector cytotoxic cells and target-cell membrane to induction of apoptosis.

  12. Mutagenicity of 2-[2-(acetylamino)-4-[bis(2-hydroxyethyl)amino]-5-methoxyphenyl]-5-amino-7-bromo-4-chloro-2H-benzotriazole (PBTA-6) and benzo[a]pyrene (BaP) in the gill and hepatopancreas of rpsL transgenic zebrafish.

    Science.gov (United States)

    Amanuma, Kimiko; Tone, Suguru; Nagaya, Masato; Matsumoto, Michi; Watanabe, Tetsushi; Totsuka, Yukari; Wakabayashi, Keiji; Aoki, Yasunobu

    2008-10-30

    We examined the in vivo mutagenicity of 2-[2-(acetylamino)-4-[bis(2-hydroxyethyl)amino]-5-methoxyphenyl]-5-amino-7-bromo-4-chloro-2H-benzotriazole (PBTA-6) and benzo[a]pyrene (BaP) by using transgenic (Tg) zebrafish carrying the mutational target gene rpsL. PBTA-6 is one of the PBTA-type compounds that were recently identified in highly mutagenic river water in Japan. BaP is a well-known contaminant that is frequently found in polluted water. Both compounds are potent mutagens, as determined by using the Ames test employing S9 mix and Salmonella. Adult rpsL Tg zebrafish were exposed to 0, 7, or 10 mg/L PBTA-6 or 0, 1.5, or 3 mg/L BaP for 96 h in a water bath and the mutations in their gills and hepatopancreata were measured 2-4 weeks later. At 3 weeks after exposure, 3 mg/L BaP significantly increased the rpsL mutant frequency (MF) in the gill and hepatopancreas by 5- and 2.3-fold, respectively, as compared to control fish. Sequence analysis showed that BaP mainly induced G:C to T:A and G:C to C:G transversions, which is consistent with the known mutagenic effects of BaP. In contrast, despite its extremely high mutagenic potency in Salmonella strains, PBTA-6 did not significantly increase the MF in the zebrafish gill or hepatopancreas. Although PBTA-6 is 300 times more mutagenic than BaP in the Ames test [T. Watanabe, H. Nukaya, Y. Terao, Y. Takahashi, A. Tada, T. Takamura, H. Sawanishi, T. Ohe, T. Hirayama, T. Sugimura, K. Wakabayashi, Synthesis of 2-phenylbenzotriazole-type mutagens, PBTA-5 and PBTA-6, and their detection in river water from Japan, Mutat. Res. 498 (2001) 107-115], calculation of the mutagenicity per mole of compound indicated that PBTA-6 was 33- and BaP.

  13. Determinação do coeficiente de distribuição (Kd de benzo(apireno em solo por isotermas de sorção Determination of the distribution coefficient (kd of benzo(apyrene in soil using sorption isotherms

    Directory of Open Access Journals (Sweden)

    Adriana D'Agostinho

    2006-07-01

    Full Text Available Leaking of diesel oil from gas stations is frequent in Brazil. The presence of polycyclic aromatic hydrocarbons (PAHs, which are highly toxic is an indication of contamination by heavy hydrocarbons from diesel oil. Here were present the determination of the distribution coefficient (Kd of benzo(apyrene (the most carcinogenic of the PAHs in tropical soils using the sorption isotherm model. The sorption curves acquired for benzo(apyrene were of the S-type, probably due to the water/methanol experimental conditions. The sorption curves allowed calculation of the distribution coefficient (Kd. The experimental Kd values were lower than those calculated from literature Koc values (partition coefficient normalized by organic carbon, due mainly to the cosolvency effect and the percentage of organic matter and clay in soil.

  14. Risk analysis of processing methods on benzo(a)pyrene contamination in oil-tea camellia seed oil%加工方式对油茶籽油苯并(a)芘污染的风险分析

    Institute of Scientific and Technical Information of China (English)

    王亚萍; 费学谦; 王开良; 姚小华; 罗凡

    2013-01-01

    根据苯并(a)芘的性质,研究了不同加工方式对油茶籽油苯并(a)芘污染的影响,并提出了控制措施.结果表明,正常压榨的油茶籽油不存在苯并(a)芘污染的风险;油茶籽炒焦容易导致油中苯并(a)芘含量上升;相对于压榨工艺,溶剂浸出工艺制取的油茶籽油苯并(a)芘超标的风险更大,其中浸出溶剂的选择是苯并(a)芘超标与否的关键因素;精炼过程可以有效去除油茶籽油中的苯并(a)芘.避免炒焦和带壳压榨、选用合格的浸出溶剂是控制油茶籽油苯并(a)芘污染的关键.%According to benzo(a)pyrene's properties, the influences of different processing methods on the risk of benzo ( a) pyrene contamination in oil - tea camellia seed oil were studied, and control measures were proposed. The results showed that the oil - tea camellia seed oil extracted by traditional pressing didn't have benzo(a)pyrene contamination risk;excessive frying usually caused high content of benzo(a) pyrene in the oil; compared with pressing process, solvent extraction brought more risk of benzo (a) pyrene in the oil and the selection of solvent was a key factor;refining process could remove benzo (a) pyrene in oil - tea camellia seed oil. In order to prevent benzo( a) pyrene exceeding national standard,excessive frying and in -shell pressing should be avoided and qualified solvent should be selected.

  15. Virus Infection-Induced Bronchial Asthma Exacerbation

    Directory of Open Access Journals (Sweden)

    Mutsuo Yamaya

    2012-01-01

    Full Text Available Infection with respiratory viruses, including rhinoviruses, influenza virus, and respiratory syncytial virus, exacerbates asthma, which is associated with processes such as airway inflammation, airway hyperresponsiveness, and mucus hypersecretion. In patients with viral infections and with infection-induced asthma exacerbation, inflammatory mediators and substances, including interleukins (ILs, leukotrienes and histamine, have been identified in the airway secretions, serum, plasma, and urine. Viral infections induce an accumulation of inflammatory cells in the airway mucosa and submucosa, including neutrophils, lymphocytes and eosinophils. Viral infections also enhance the production of inflammatory mediators and substances in airway epithelial cells, mast cells, and other inflammatory cells, such as IL-1, IL-6, IL-8, GM-CSF, RANTES, histamine, and intercellular adhesion molecule-1. Viral infections affect the barrier function of the airway epithelial cells and vascular endothelial cells. Recent reports have demonstrated augmented viral production mediated by an impaired interferon response in the airway epithelial cells of asthma patients. Several drugs used for the treatment of bronchial asthma reduce viral and pro-inflammatory cytokine release from airway epithelial cells infected with viruses. Here, I review the literature on the pathogenesis of the viral infection-induced exacerbation of asthma and on the modulation of viral infection-induced airway inflammation.

  16. Bradykinin-induced proinflammatory signaling mechanisms.

    Science.gov (United States)

    Shigematsu, Sakuji; Ishida, Shuji; Gute, Dean C; Korthuis, Ronald J

    2002-12-01

    Intravital microscopic techniques were used to examine the mechanisms underlying bradykinin-induced leukocyte/endothelial cell adhesive interactions (LECA) and venular protein leakage (VPL) in single postcapillary venules of the rat mesentery. The effects of bradykinin superfusion to increase LECA and VPL were prevented by coincident topical application of either a bradykinin-B(2) receptor antagonist, a cell-permeant superoxide dismutase (SOD) mimetic or antioxidant, or inhibitors of cytochrome P-450 epoxygenase (CYPE) or protein kinase C (PKC) but not by concomitant treatment with either SOD, a mast cell stabilizer, or inhibitors of nitric oxide synthase, cyclooxygenase, xanthine oxidase, NADPH oxidase, or platelet-activating factor. Immunoneutralizing P-selectin or intercellular adhesion molecule-1 (ICAM-1) completely prevented bradykinin-induced leukocyte adhesion and emigration but did not affect VPL. On the other hand, stabilization of F-actin with phalloidin prevented bradykinin-induced leukocyte emigration and VPL but did not alter leukocyte adhesion. These data indicate that bradykinin induces LECA in rat mesenteric venules via a B(2)-receptor-initiated, CYPE-, oxidant- and PKC-mediated, P-selectin- and ICAM-1-dependent mechanism. Bradykinin also produced VPL, an effect that was initiated by stimulation of B(2) receptors and involved CYPE and PKC activation, oxidant generation, and cytoskeletal reorganization but was independent of leukocyte adherence and emigration. PMID:12388246

  17. Induced Abortion

    Science.gov (United States)

    ... Education & Events Advocacy For Patients About ACOG Induced Abortion Home For Patients Search FAQs Induced Abortion Page ... Induced Abortion FAQ043, May 2015 PDF Format Induced Abortion Special Procedures What is an induced abortion? What ...

  18. Effects of particulate carbonaceous matter on the bioavailability of benzo[a]pyrene and 2,2‘,5,5‘-tetrachlorobiphenyl to the clam, Macoma balthica

    Science.gov (United States)

    McLeod, Pamela B.; van den Heuvel-Greve, Martine J.; Allen-King, Richelle M.; Luoma, Samuel N.; Luthy, Richard G.

    2004-01-01

    We investigated the bioavailability via diet of spiked benzo[a]pyrene (BaP) and 2,2‘,5,5‘-tetrachlorobiphenyl (PCB-52) from different carbonaceous (non-carbonate, carbon containing) particle types to clams (Macoma balthica) collected from San Francisco Bay. Our results reveal significant differences in absorption efficiency between compounds and among carbonaceous particle types. Absorption efficiency for PCB-52 was always greater than that for BaP bound to a given particle type. Among particles, absorption efficiency was highest from wood and diatoms and lowest from activated carbon. Large differences in absorption efficiency could not be simply explained by comparatively small differences in the particles' total organic carbon content. BaP and PCB-52 bound to activated carbon exhibited less than 2% absorption efficiency and were up to 60 times less available to clams than the same contaminants associated with other types of carbonaceous matter. These results suggest that variations in the amount and type of sediment particulate carbonaceous matter, whether naturally occurring or added as an amendment, will have a strong influence on the bioavailability of hydrophobic organic contaminants. This has important implications for environmental risk assessment, sediment management, and development of novel remediation techniques.

  19. Antigenotoxic properties of Eruca sativa (rocket plant), erucin and erysolin in human hepatoma (HepG2) cells towards benzo(a)pyrene and their mode of action.

    Science.gov (United States)

    Lamy, Evelyn; Schröder, Julia; Paulus, Stefanie; Brenk, Peter; Stahl, Thorsten; Mersch-Sundermann, Volker

    2008-07-01

    In recent years, rocket plant (Eruca sativa) has gained greater importance as a vegetable and spice, especially among Europeans. E. sativa is a member of the Brassicaceae, which is considered to be an important chemopreventive plant family. In the present study, we assessed the chemopreventive potency and underlying mechanisms of extracts of E. sativa in HepG2 cells. No genotoxic effect could be observed in HepG2 cells treated with up to 50 microl/ml plant juice for 24 h when using the comet assay. In antigenotoxicity experiments, E. sativa extract reduced the benzo(a)pyrene-induced genotoxicity in a U-shaped manner. This effect was accompanied by a significant induction of glutathione S-transferase. No significant suppression of B(a)P-induced CYP1A1 protein expression or enzyme activity could be observed. Chemical analysis of the plant material by gas chromatography identified the isothiocyanates erucin, sulforaphane, erysolin and phenylethyl isothiocyanate. Results derived with the single ITC compounds support the assumption that their synergistic interaction is responsible for the strong antigenotoxicity of the plant material. The present study provided an assessment of the bioactive effects of rocket plant extract in a human cell culture system. This could help to evaluate the balance between beneficial vs. possible adverse effects of rocket plant consumption.

  20. Induction and transport of Wnt 5a during macrophage-induced malignant invasion is mediated by two types of extracellular vesicles.

    OpenAIRE

    Menck, Kerstin; Klemm, Florian; Gross, Julia Christina; Pukrop, Tobias; Wenzel, Dirk; Binder, Claudia

    2013-01-01

    Recently, we have shown that macrophage (M Phi)-induced invasion of breast cancer cells requires upregulation of Wnt 5a in M Phi leading to activation of beta-Cateninin-dependent Wnt signaling in the tumor cells. However, it remained unclear, how malignant cells induce Wnt 5a in M Phi and how it is transferred back to the cancer cells. Here we identify two types of extracellular particles as essential for this intercellular interaction in both directions. Plasma membrane-derived microvesicles...

  1. Lung apoptosis after intra-pulmonary instillation of Benzo(apyrene in Wistar rats Apoptose pulmonar após instilação intrapulmonar de Benzo(apireno em ratos Wistar

    Directory of Open Access Journals (Sweden)

    Baldomero Antonio Kato da Silva

    2010-02-01

    Full Text Available PURPOSE: To evaluate the influence of pulmonary instillation of Benzo[a]pyrene in lung apoptosis of Wistar rats. METHODS: Male Rattus norvegicus albinus, Wistar lineage was carried through an intra-pulmonary instillation of the Benzo[a]pyrene (B[a]P dilution in alcohol 70%. Three experimental groups had been formed with 08 animals each: Control Group (Alcohol 70%; B[a]P Group 40 mg/kg; e B[a]P Group 80mg/kg, submitted to euthanasia 16 and 18 weeks after the experimental procedure. The pulmonary sections had been processed by TUNEL method and submitted to the histomorphometric analysis to quantify the apoptotic cell number. RESULTS: After 16 weeks, mean of apoptotic cells number in control group (19,3±3,2 was greater than 40mg/Kg group (11,8±1,9; pOBJETIVO: Avaliar a influência da instilação intrapulmonar de Benzo[a]pireno na apoptose pulmonar de ratos Wistar. MÉTODOS: Rattus norvegicus albinus, linhagem Wistar machos foram submetidos à instilação intra-pulmonar da diluição em álcool 70% de Benzo[a]pireno (B[a]P. Foram formados três grupos experimentais com 08 animais cada: Grupo Controle (álcool 70%; Grupo B[a]P 40 mg/kg; e Grupo B[a]P 80mg/kg, submetidos a eutanásia 16 e 18 semanas após o procedimento experimental. As secções pulmonares foram processadas pelo método TUNEL e submetidas à análise histomorfométrica para quantificação do número de células apoptóticas. RESULTADOS: Após 16 semanas, a média do número de células apoptóticas do grupo controle (19,3±3,2 mostrou-se maior que o grupo 40mg/Kg (11,8±1,9; p<0,01 e 80mh/Kg (7,0±1,4; p<0,01. Diferença significante foi também observada entre os grupos 40mg/Kg e 80mg/Kg (p<0,05. Após 18 semanas, a média do número de células apoptóticas do grupo controle (18,0±2,2 mostrou-se maior que o grupo 40mg/Kg (8,8±1,7; p<0,01 e 80mh/Kg (5,5±1,3; p<0,01. Não foi observada diferença significante entre os grupos 40 e 80mg/Kg (ns. CONCLUSÃO: A instila

  2. Electrochemical immunoassay of benzo[a]pyrene based on dual amplification strategy of electron-accelerated Fe{sub 3}O{sub 4}/polyaniline platform and multi-enzyme-functionalized carbon sphere label

    Energy Technology Data Exchange (ETDEWEB)

    Lin Mouhong [Institute of Biomaterials, College of Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province (China); Liu Yingju, E-mail: liuyingju@hotmail.com [Institute of Biomaterials, College of Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province (China); Sun Zihong; Zhang Shenglai; Yang Zhuohong [Institute of Biomaterials, College of Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province (China); Ni Chunlin, E-mail: niclchem@scau.edu.cn [Institute of Biomaterials, College of Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province (China)

    2012-04-13

    Graphical abstract: Schematic representation of Fe{sub 3}O{sub 4}/PANI/Nafion-based immunosensor using multi-HRP-HCS-Ab{sub 2} bioconjugates as labels. Highlights: Black-Right-Pointing-Pointer An electrochemical immunosensor for high sensitive detection of BaP. Black-Right-Pointing-Pointer A dual amplification strategy by Fe{sub 3}O{sub 4}/PANI/Nafion film and multi-HRP-HCS-Ab{sub 2} label. Black-Right-Pointing-Pointer An accelerated electron transfer pathway by the Fe{sub 3}O{sub 4}/PANI/Nafion film. - Abstract: An electrochemical immunosensor, basing on a dual amplification strategy by employing a biocompatible Fe{sub 3}O{sub 4}/polyaniline/Nafion (Fe{sub 3}O{sub 4}/PANI/Nafion) layer as sensor platform and multi-enzyme-antibody functionalized highly-carbonized spheres (multi-HRP-HCS-Ab{sub 2}) as label, was constructed for sensitive detection of benzo[a]pyrene (BaP). The stable film, Fe{sub 3}O{sub 4}/PANI/Nafion, can not only immobilize biomolecules, but also catalyze the reduction of hydrogen peroxide, indicating an accelerated electron transfer pathway of the platform. The experimental conditions, including the concentration of Nafion, concentration of Fe{sub 3}O{sub 4}/polyaniline (Fe{sub 3}O{sub 4}/PANI), pH of the detection solution and concentrations of biomolecules, were studied in detail. Basing on a competitive immunoassay, the current change was proportional to the logarithm of BaP concentration in the range of 8 pM and 2 nM with the detection limit of 4 pM. The proposed immunosensor exhibited acceptable reproducibility and stability. This new type of dual amplification strategy may provide potential applications for the detection of environmental pollutants.

  3. Cytochrome P4501A induction, benzo[a]pyrene metabolism, and nucleotide adduct formation in fish hepatoma cells: Effect of preexposure to 3,3',4,4',5-pentachlorobiphenyl

    Science.gov (United States)

    Smeets, J.M.W.; Voormolen, A.; Tillitt, D.E.; Everaarts, J.M.; Seinen, W.; Vanden Berg, M.D.

    1999-01-01

    In PLHC-1 hepatoma cells, benzo[a]pyrene (B[a]P) caused a maximum induction of cytochrome P4501A (CYP1A) activity, measured as ethoxyresorufin O-deethylation (EROD), after 4 to 8 h of exposure, depending on the B[a]P concentration. The decline of EROD activity at longer exposure times was probably caused by the rapid metabolism of B[a]P in this system (57% metabolism within 4 h incubation). In subsequent experiments, PLHC-1 cells were preinduced with PCB 126 for 24 h and then received a dose of 10, 100, or 1,000 nM 3H-B[a]P. A 1-nM concentration of PCB 126 caused an 80-fold induction of CYP1A activity, resulting in an increase in B[a]P metabolism of less than 10%, except at the highest concentration of B[a]P (1,000 nM), where a 50% increase was observed. In another experiment, an 80-fold induction of CYP1A activity caused a 20% increase in the metabolism of B[a]P (100 nM), and RNA adduct formation was increased approximately twofold. These results indicate that, at exposure concentrations up to 100 nM B[a]P, CYP1A activity is not rate limiting for B[a]P metabolism. Furthermore, CYP1A seems to also he specifically involved in B[a]P activation in PLHC-1 cells. However, CYP1A induction causes only a relatively small increase in activation, probably because of the action of other enzymes involved in B[a]P activation and deactivation.

  4. Benzo[a]pyrene diol epoxide suppresses retinoic acid receptor-β2 expression by recruiting DNA (cytosine-5--methyltransferase 3A

    Directory of Open Access Journals (Sweden)

    Xu Xiao-Chun

    2010-04-01

    Full Text Available Abstract Tobacco smoke is an important risk factor for various human cancers, including esophageal cancer. How benzo [a]pyrene diol epoxide (BPDE, a carcinogen present in tobacco smoke as well as in environmental pollution, induces esophageal carcinogenesis has yet to be defined. In this study, we investigated the molecular mechanism responsible for BPDE-suppressed expression of retinoic acid receptor-beta2 (RAR-β2 in esophageal cancer cells. We treated esophageal cancer cells with BPDE before performing methylation-specific polymerase chain reaction (MSP to find that BPDE induced methylation of the RAR-β2 gene promoter. We then performed chromatin immunoprecipitation (ChIP assays to find that BPDE recruited genes of the methylation machinery into the RAR-β2 gene promoter. We found that BPDE recruited DNA (cytosine-5--methyltransferase 3 alpha (DNMT3A, but not beta (DNMT3B, in a time-dependent manner to methylate the RAR-β2 gene promoter, which we confirmed by reverse transcription-polymerase chain reaction (RT-PCR analysis of the reduced RAR-β2 expression in these BPDE-treated esophageal cancer cell lines. However, BPDE did not significantly change DNMT3A expression, but it slightly reduced DNMT3B expression. DNA methylase inhibitor 5-aza-2'-deoxycytidine (5-Aza and DNMT3A small hairpin RNA (shRNA vector antagonized the effects of BPDE on RAR-β2 expressions. Transient transfection of the DNMT3A shRNA vector also antagonized BPDE's effects on expression of RAR-β2, c-Jun, phosphorylated extracellular signal-regulated protein kinases 1/2 (ERK1/2, and cyclooxygenase-2 (COX-2, suggesting a possible therapeutic effect. The results of this study form the link between the esophageal cancer risk factor BPDE and the reduced RAR-β2 expression.

  5. 骨桥蛋白对大肠癌细胞间隙连接通信的影响%Effects of osteopontin on gap junctional intercellular communication in colon cancer cell lines

    Institute of Scientific and Technical Information of China (English)

    丁凌; 胡涵光; 郑树

    2011-01-01

    ObjectiveLiver metastasis is a major cause of mortality in patients with colorectal cancer. However, the mechanisms underlying this process remain largely unknown. Osteopontin (OPN) is a secreted phosphorylated glycoprotein known to be involved in tumor migration and metastasis. Gap junction intercellular communication (GJIC) is a pathway of direct cell to cell communication. This study analyzed gap junctional intercellular communication(GJIC)changes in colon cancer SW-480 cell lines after osteopontin had been transfected in. MethodsTransfect sense-osteopontin eukaryotic expression plasmids into SW-480 cell lines and detect the GJIC changes in two different cell lines by flurescence redistribution after photobleaching ( FRAP).ResultsCompared with control, signal exchange is impaired and GJIC function is inhibited in SW-480-pcDNA3. 1 ( + )-OPN cell lines. FRAP after 5 min in SW-48O-pcDNA3. 1 ( + )-OPN is 24. 65% ± 4. 08%, the control SW-480-pcDNA3. 1 ( + ) is 44. 74% ± 6. 23%, P < 0. 001 ;FRAP after 10 min in SW-480-pcDNA3. 1 ( + )-OPN is 25.98% ±4.48%, while SW-480-pcDNA3. 1 is up to 64. 92% ± 5.39%, P < 0.001. ConclusionOPN could inhibit GJIC function of colon cells to accelerate the metastatic process in colorectal cancer.%目的 检测骨桥蛋白( Osteopontin,OPN)转染后大肠癌SW-480细胞株的细胞间隙连接通信( gap junctional intercellular communication,GJIC)改变。方法 以OPN真核表达质粒转染大肠癌SW-480细胞株后,利用激光共聚焦显微镜(laser scanning confocal microscope,LSCM),运用荧光淬灭后恢复技术(flurescence redistribution after photobleaching,FRAP)检测OPN转染后SW-480细胞的GJIC功能变化。结果 转染OPN后,高表达OPN的SW-480-pcDNA3.1(+)-OPN细胞株淬灭5 min 后荧光恢复率为24.65%±4.08%,而对照组SW-480-pcDNA3.1(+)为44.74% ±6.23%,P<0.001;10 min后荧光恢复率SW-480-pcDNA3.1(+)-OPN仅为25.98%±4.48%,SW-480-pcDNA3

  6. Proteomic analysis of MCF-7 cells treated with benzo(a)pyrene, dibenzo(a,l)pyrene, coal tar extract, and diesel exhaust extract

    Energy Technology Data Exchange (ETDEWEB)

    Hooven, L.A.; Baird, W.M. [Oregon State University, Corvallis, OR (United States). Dept. for Zoology

    2008-07-15

    Polycyclic aromatic hydrocarbon (PAH) DNA adducts have been associated with carcinogenesis, which is accompanied by multiple alterations in gene expression. We used two-dimensional electrophoresis to distinguish protein expression changes induced in MCF-7 cells by individual PAH (B(a)P and DB(a,l)P) and PAH mixtures (coal tar extract (SRM 1597) and diesel exhaust extract (SRM 1975)). Spots of interest were identified by MALDI-TOF-TOF. Our results have shown alterations in the expression of heat-shock proteins, cytoskeletal proteins, DNA associated proteins, and glycolytic and mitochondrial proteins. The proteins that were universally altered in expression were actin cytoplasmic 1, tubulin alpha and myosin light chain alkali, cyclophilin B, and heterogeneous ribonucleoprotein B1 (a protein involved in access to telomerase and mRNA maturation). Additional proteins with altered expression include histone H{sub 2}A.1, heat-shock