GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Distinct Phospholipases A2 Regulate the Release of Arachidonic Acid for Eicosanoid Production and Superoxide Anion Generation in Neutrophils
    The American Association of Immunologists ; 1998
    In:  The Journal of Immunology Vol. 160, No. 2 ( 1998-01-15), p. 953-960
    Details
    In: The Journal of Immunology, The American Association of Immunologists, Vol. 160, No. 2 ( 1998-01-15), p. 953-960
    Abstract: Arachidonic acid (AA) released from membrane phospholipids by phospholipase A2 (PLA2) is important as a substrate for eicosanoid formation and as a second messenger for superoxide anion (O2−) generation in neutrophils. Different isoforms of PLA2 in neutrophils might mobilize AA for different functions. To test this possibility, we sought to characterize the PLA2s that are activated by the neutrophil stimuli, Aroclor 1242, a mixture of polychlorinated biphenyls, and A23187, a calcium ionophore. Both Aroclor 1242 and A23187 caused release of [3H]AA; however, O2− production was seen only in response to Aroclor 1242. Eicosanoids accounted for & gt;85% of the radioactivity recovered in the supernatant of A23187-stimulated cells but & lt;20% of the radioactivity recovered from cells exposed to Aroclor 1242. Omission or chelation of calcium abolished A23187-induced AA release, but did not alter AA release in Aroclor 1242-stimulated neutrophils. AA release and O2− production in response to Aroclor 1242 were inhibited by bromoenol lactone (BEL), an inhibitor of calcium-independent PLA2. BEL, however, did not alter A23187-induced release of AA. Cell-free assays demonstrated both calcium-dependent and calcium-independent PLA2 activity. Calcium-independent activity was inhibited & gt;80% by BEL, whereas calcium-dependent activity was inhibited & lt;5%. Furthermore, calcium-independent, but not calcium-dependent, PLA2 activity was significantly enhanced by Aroclor 1242. These data suggest that Aroclor 1242 and A23187 activate distinct isoforms of PLA2 that are linked to different functions: Aroclor 1242 activates a calcium-independent PLA2 that releases AA for the generation of O2−, and A23187 activates a calcium-dependent PLA2 that mobilizes AA for eicosanoid production.
    Type of Medium: Online Resource
    ISSN: 0022-1767 , 1550-6606
    URL: Article
    DOI: 10.4049/jimmunol.160.2.953
    RVK:
    XA 54100
    RVK:
    XA 10000
    Language: English
    Publisher: The American Association of Immunologists
    Publication Date: 1998
    detail.hit.zdb_id: 1475085-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Identification of factors from rat neutrophils responsible for cytotoxicity to isolated hepatocytes
    Oxford University Press (OUP) ; 1996
    In:  Journal of Leukocyte Biology Vol. 59, No. 5 ( 1996-05-01), p. 716-724
    Details
    In: Journal of Leukocyte Biology, Oxford University Press (OUP), Vol. 59, No. 5 ( 1996-05-01), p. 716-724
    Abstract: Activated polymorphonuclear neutrophils (PMNs) have been shown to be cytotoxic to rat hepatic parenchymal cells in vitro. This cytotoxicity could be observed without direct cell-cell contact, since the conditioned medium from PMNs activated with formyl-Met-Leu-Phe (fMLP) was effective in hepatocyte killing. To identify the toxic factor(s) released by PMNs, degranulation was induced by fMLP in PMNs pretreated with cytochalasin B. The contents released from the phagocytes were subjected to gel filtration on a Sephadex G-100 column. Resulting fractions were tested for cytotoxicity to isolated hepatocytes by using release of alanine aminotransferase as a marker for hepatocyte injury. Cytotoxicity was associated with fractions containing cathepsin G and elastase and not with other fractions, including those containing myeloperoxidase. The former two enzymes were purified to homogeneity with a carboxymethyl cellulose column. Each of these enzymes demonstrated concentration-dependent cytotoxicity to hepatocytes at concentrations & gt;2 μg/mL. Moreover, they exhibited an additive cytotoxic effect. Effective concentrations for the combined cathepsin C and elastase in the incubation mixture were similar to the concentrations of these enzymes in PMN-conditioned medium that produced cytotoxicity to hepatocytes. Cytotoxicity of either purified enzyme or of conditioned medium could be prevented by plasma α-1-antitrypsin or soybean trypsin-chymotrypsin inhibitor, which were also potent inhibitors of enzymic activity of both cathepsin G and elastase. By contrast, the serine protease inhibitors, aprotinin and 4-(2-aminoethyl)-benzenesulfonyl fluoride, were less effective in inhibiting cathepsin G and elastase activities as well as cytotoxicity caused by the purified proteases or PMN-conditioned medium. These results support the hypothesis that cathepsin G and elastase are important mediators of hepatic parenchymal cell killing produced by activated PMNs in vitro.
    Type of Medium: Online Resource
    ISSN: 0741-5400 , 1938-3673
    URL: Article
    DOI: 10.1002/jlb.59.5.716
    RVK:
    XA 10000
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 1996
    detail.hit.zdb_id: 2026833-6
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Abstract 4378: Aflatoxin B1 inhibits LPS-induced TNF-alpha production in RAW 264.7 cells
    American Association for Cancer Research (AACR) ; 2010
    In:  Cancer Research Vol. 70, No. 8_Supplement ( 2010-04-15), p. 4378-4378
    Details
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 70, No. 8_Supplement ( 2010-04-15), p. 4378-4378
    Abstract: Aflatoxin B1 (AFB1), a potent hepatocarcinogen, is known to impair specific and nonspecific immune responses. Recent studies suggested that AFB1 affects macrophage functions. Macrophages play an important role in a host defense against tumors and bacteria. In addition, some macrophage products, including tumor necrosis alpha (TNF-alpha), can be cytotoxic. In the present study, we investigated the effect of aflatoxin B1 (AFB1) on LPS-induced TNF-alpha production by a mouse macrophage cell line, RAW 264.7 cells. Cells were pretreated with increasing concentrations of AFB1 for 2 hours followed by stimulation with lipopolysaccharide (LPS) for 6 h. The concentration of TNF-alpha released in the culture medium was assessed by enzyme-linked immunosorbent assay (ELISA). AFB1 at 1, 10, 50 or 100 µM reduced the production of TNF-alpha induced by LPS. Compared to vehicle control, there was a greater reduction of TNF-alpha production with increased concentration of AFB1 pretreatment and LPS stimulation. AFB1 at 100 µM decreased the synthesis of both TNF-alpha mRNA and protein in RAW 264.7 cells. To explore the mechanism of AFB1 activation by RAW 264.7 cells, we examined the expression of CYP3A4 and CYP3A11, two isoforms of cytochrome p450 known to activate AFB1. Our data indicated that CYP3A11 but not CYP3A4 was significantly expressed in RAW 264.7 cells. These results suggest that AFB1 pretreatment suppresses LPS-induced TNF production in RAW 264.7 cells. (Supported by NIH grant R01ES04139.) Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4378.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    URL: Article
    DOI: 10.1158/1538-7445.AM10-4378
    RVK:
    XA 36000
    RVK:
    XA 10000
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2010
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Platelets and protease-activated receptor-4 contribute to acetaminophen-induced liver injury in mice
    American Society of Hematology ; 2015
    In:  Blood Vol. 126, No. 15 ( 2015-10-08), p. 1835-1843
    Details
    In: Blood, American Society of Hematology, Vol. 126, No. 15 ( 2015-10-08), p. 1835-1843
    Abstract: Platelets and PAR-4 contribute to the progression of APAP-induced liver injury in mice through independent pathways.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    URL: Article
    DOI: 10.1182/blood-2014-09-598656
    RVK:
    XA 33000
    RVK:
    XA 10000
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2015
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    6‐Ketoprostaglandin F 1α and thromboxane B 2 in isolated, blood‐perfused lungs from monocrotaline pyrrole‐treated rats
    Informa UK Limited ; 1988
    In:  Journal of Toxicology and Environmental Health Vol. 23, No. 1 ( 1988-01), p. 127-137
    Details
    In: Journal of Toxicology and Environmental Health, Informa UK Limited, Vol. 23, No. 1 ( 1988-01), p. 127-137
    Type of Medium: Online Resource
    ISSN: 0098-4108
    URL: Article
    DOI: 10.1080/15287398809531099
    RVK:
    XA 43700
    Language: English
    Publisher: Informa UK Limited
    Publication Date: 1988
    detail.hit.zdb_id: 2067440-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Arachidonic Acid Metabolites and the Mechanisms of Monocrotaline Pneumotoxicity
    American Thoracic Society ; 1987
    In:  American Review of Respiratory Disease Vol. 136, No. 3 ( 1987-08), p. 762-765
    Details
    In: American Review of Respiratory Disease, American Thoracic Society, Vol. 136, No. 3 ( 1987-08), p. 762-765
    Type of Medium: Online Resource
    ISSN: 0003-0805
    URL: Article
    DOI: 10.1164/ajrccm/136.3.762
    RVK:
    XA 21200
    Language: English
    Publisher: American Thoracic Society
    Publication Date: 1987
    detail.hit.zdb_id: 1468352-0
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...