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Du Y, Taylor CG, Aukema HM, Zahradka P. Role of oxylipins generated from dietary PUFAs in the modulation of endothelial cell function. Prostaglandins Leukot Essent Fatty Acids 2020; 160:102160. [PMID: 32717531 DOI: 10.1016/j.plefa.2020.102160] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 07/17/2020] [Accepted: 07/17/2020] [Indexed: 12/13/2022]
Abstract
Oxylipins, which are circulating bioactive lipids generated from polyunsaturated fatty acids (PUFAs) by cyclooxygenase, lipooxygenase and cytochrome P450 enzymes, have diverse effects on endothelial cells. Although studies of the effects of oxylipins on endothelial cell function are accumulating, a review that provides a comprehensive compilation of current knowledge and recent advances in the context of vascular homeostasis is lacking. This is the first compilation of the various in vitro, ex vivo and in vivo reports to examine the effects and potential mechanisms of action of oxylipins on endothelial cells. The aggregate data indicate docosahexaenoic acid-derived oxylipins consistently show beneficial effects related to key endothelial cell functions, whereas oxylipins derived from other PUFAs exhibit both positive and negative effects. Furthermore, information is lacking for certain oxylipin classes, such as those derived from α-linolenic acid, which suggests additional studies are required to achieve a full understanding of how oxylipins affect endothelial cells.
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Affiliation(s)
- Youjia Du
- Canadian Centre for Agri-Food Research in Health and Medicine, St Boniface Albrechtsen Research Centre, Winnipeg, MB R2H 2A6, Canada; Department of Physiology and Pathophysiology, University of Manitoba, MB R3E 0J9, Canada
| | - Carla G Taylor
- Canadian Centre for Agri-Food Research in Health and Medicine, St Boniface Albrechtsen Research Centre, Winnipeg, MB R2H 2A6, Canada; Department of Physiology and Pathophysiology, University of Manitoba, MB R3E 0J9, Canada; Department of Food and Human Nutritional Sciences, University of Manitoba, MB R3T 2N2, Canada
| | - Harold M Aukema
- Canadian Centre for Agri-Food Research in Health and Medicine, St Boniface Albrechtsen Research Centre, Winnipeg, MB R2H 2A6, Canada; Department of Food and Human Nutritional Sciences, University of Manitoba, MB R3T 2N2, Canada
| | - Peter Zahradka
- Canadian Centre for Agri-Food Research in Health and Medicine, St Boniface Albrechtsen Research Centre, Winnipeg, MB R2H 2A6, Canada; Department of Physiology and Pathophysiology, University of Manitoba, MB R3E 0J9, Canada; Department of Food and Human Nutritional Sciences, University of Manitoba, MB R3T 2N2, Canada.
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Grumbach Y, Quynh NVT, Chiron R, Urbach V. LXA4 stimulates ZO-1 expression and transepithelial electrical resistance in human airway epithelial (16HBE14o-) cells. Am J Physiol Lung Cell Mol Physiol 2008; 296:L101-8. [PMID: 18849442 DOI: 10.1152/ajplung.00018.2008] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Lipoxin A(4) (LXA(4)) is a biologically active eicosanoid produced in human airways that displays anti-inflammatory properties. In cystic fibrosis and severe asthma, LXA(4) production has been reported to be decreased, and, in such diseases, one of the consequences of airway inflammation is disruption of the tight junctions. In the present study, we investigated the possible role of LXA(4) on tight junction formation, using transepithelial electrical resistance (TER) measurements, Western blotting, and immunofluorescence. We observed that exposure to LXA(4) (100 nM) for 2 days significantly increased zonula occludens-1 (ZO-1), claudin-1, and occludin expression at the plasma membrane of confluent human bronchial epithelial 16HBE14o- cells. LXA(4) (100 nM) stimulated the daily increase of the 16HBE14o- cell monolayer TER, and this effect was inhibited by boc-2 (LXA(4) receptor antagonist). LXA(4) also had a rapid effect on ZO-1 immunofluorescence at the plasma membrane and increased TER within 10 min. In conclusion, our experiments provide evidence that LXA(4) plays certainly a new role for the regulation of tight junction formation and stimulation of the localization and expression of ZO-1 at the plasma membrane through a mechanism involving the LXA(4) receptor.
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Affiliation(s)
- Yael Grumbach
- Institut National de la Santé et de la Recherche Médicale U454, Centre Hospitalier Universitaire Arnaud de Villeneuve, Montpellier, France
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Menezes-de-Lima O, Kassuya CAL, Nascimento AFZ, Henriques MDGMO, Calixto JB. Lipoxin A4 inhibits acute edema in mice: Implications for the anti-edematogenic mechanism induced by aspirin. Prostaglandins Other Lipid Mediat 2006; 80:123-35. [PMID: 16939877 DOI: 10.1016/j.prostaglandins.2006.05.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2006] [Revised: 05/19/2006] [Accepted: 05/24/2006] [Indexed: 10/24/2022]
Abstract
Lipoxin A4 (LXA4) is a lipid mediator that plays an important role in the resolution of inflammation. However, the role of LXA4 and aspirin (ASA)-triggered lipoxins (ATLs) in inflammatory edema formation remains unclear. Here, we investigated the inhibitory role played by LXA4 in the carrageenan-induced and other inflammatory mediator-induced edematogenic response in mice, and also assessed the role of ATLs in the anti-edematogenic action of aspirin. Our results showed that LXA4 (1-20 ng/paw or 5 microg/kg i.p.) was effective in inhibiting carrageenan-induced paw edema from 30 min to 2 h. LXA4 (10 ng/paw) was also able to acutely inhibit PAF-, histamine-, PGE2- or bradykinin-induced paw edema, as well as the PAF-induced myeloperoxidase activity increase in the paws. Likewise, LXA4 (10 ng/cavity) also inhibited the pleural edema triggered by histamine (1h), and this response was not followed by leukocyte accumulation. Of note, the lipoxin receptor (ALX-r) antagonist Boc2 (butoxycarbonyl-Phe-Leu-Phe-Leu-Phe, 200 ng/paw) significantly reverted the anti-edematogenic effect of ASA (300 mg/kg p.o.) against carrageenan, PAF, PGE2 and BK, without affecting the anti-edematogenic action caused by indomethacin (3 mg/kg i.p.) in the carrageenan-induced paw edema. Collectively, our results demonstrate for the first time that LXA4 displays an acute and rapid onset anti-edematogenic activity that does not discriminate among different pro-inflammatory stimuli, an effect that is most likely independent of its action on the leukocyte influx. Finally, the present study demonstrates that ATLs exert a very important role in the acute anti-edematogenic action of ASA.
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Affiliation(s)
- Octavio Menezes-de-Lima
- Department of Pharmacology, Universidade Federal de Santa Catarina, Campus Universitário, Trindade, Florianópolis, SC, Brazil
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4
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Serhan CN. Lipoxins and aspirin-triggered 15-epi-lipoxins are the first lipid mediators of endogenous anti-inflammation and resolution. Prostaglandins Leukot Essent Fatty Acids 2005; 73:141-62. [PMID: 16005201 DOI: 10.1016/j.plefa.2005.05.002] [Citation(s) in RCA: 319] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Lipoxins (LXs) or the lipoxygenase interaction products are generated from arachidonic acid via sequential actions of lipoxygenases and subsequent reactions to give specific trihydroxytetraene-containing eicosanoids. These unique structures are formed during cell-cell interactions and appear to act at both temporal and spatially distinct sites from other eicosanoids produced during the course of inflammatory responses and to stimulate natural resolution. Lipoxin A4 (LXA4) and lipoxin B4 (LXB4) are positional isomers that each possesses potent cellular and in vivo actions. These LX structures are conserved across species. The results of numerous studies reviewed in this work now confirm that they are the first recognized eicosanoid chemical mediators that display both potent anti-inflammatory and pro-resolving actions in vivo in disease models that include rabbit, rat, and mouse systems. LXs act at specific GPCRs as agonists to regulate cellular responses of interest in inflammation and resolution. Aspirin has a direct impact in the LX circuit by triggering the biosynthesis of endogenous epimers of LX, termed the aspirin-triggered 15-epi-LX, that share the potent anti-inflammatory actions of LX. Stable analogs of LXA4, LXB4, and aspirin-triggered lipoxin were prepared, and several of these display potent actions in vitro and in vivo. The results reviewed herein implicate a role of LX and their analogs in many common human diseases including airway inflammation, asthma, arthritis, cardiovascular disorders, gastrointestinal disease, periodontal disease, kidney diseases and graft-vs.-host disease, as well as others where uncontrolled inflammation plays a key role in disease pathogenesis. Hence, the LX pathways and mechanisms reviewed to date in this work provide a basis for new approaches to treatment of many common human diseases that involve inflammation.
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Affiliation(s)
- Charles N Serhan
- Center for Experimental Therapeutics and Reperfusion Injury, Department of Anesthesia, Perioperative and Pain Medicine, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
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Bonnans C, Chanez P, Chavis C. Lipoxins in asthma: potential therapeutic mediators on bronchial inflammation? Allergy 2004; 59:1027-41. [PMID: 15355460 DOI: 10.1111/j.1398-9995.2004.00617.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Arachidonic acid metabolism represents an important source of mediators with ambivalent actions. Among these, lipoxins (LXs) are the first agents identified and recognized as anti-inflammatory endogenous lipid mediators, which are involved in the resolution of inflammation and are present in the airways of asthmatic patients. Lipoxins result mainly from the interaction between 5 and 15-lipoxygenases (LO) and their levels are modulated by the degree of bronchial inflammation as well as by the long-term glucocorticoid treatments. In the airways, LX synthesis is higher in mild asthmatics than in severe asthmatics, whereas in vitro chemokine release inhibition by LXs is more effective in cells from severe asthmatics than from mild asthmatics. LipoxinA(4) effects on interleukin (IL)-8 released by blood mononuclear cells and on calcium influx in epithelial cells are mediated by the specific receptor ALX. Lipoxin generation by lung epithelial cells depends mainly on 15-LO activity. Mild asthmatics present higher 15-LOb expression at the epithelium level than severe patients, whereas the LX deficit in severe asthma is associated with an up-regulation of the 15-LOa expressions. Therefore, bronchial epithelial cells become a target for therapeutic intervention and LXs represent a potential therapeutic solution for bronchial inflammation resolution in asthma.
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Affiliation(s)
- C Bonnans
- Inserm U454-IFR 3, Clinique des Maladies Respiratoires, CHU de Montpellier, France
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Kieran NE, Maderna P, Godson C. Lipoxins: Potential anti-inflammatory, proresolution, and antifibrotic mediators in renal disease. Kidney Int 2004; 65:1145-54. [PMID: 15086453 DOI: 10.1111/j.1523-1755.2004.00487.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Lipoxins are lipoxygenase-derived lipid mediators with both anti-inflammatory and proresolution properties that have been demonstrated in vivo and in vitro. The bioactivity profile of lipoxins in vitro suggests that they have therapeutic potential in acute renal failure and glomerulonephritis; predictions that have been borne out to date in experimental models of renal disease. We review recent developments on the molecular basis of lipoxin bioactions mediated through receptor crosstalk and the accumulating evidence that lipoxins may have potential as novel anti-inflammatory agents.
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Affiliation(s)
- Niamh E Kieran
- Department of Medicine and Therapeutics, Mater Misericordiae University Hospital, Dublin, Ireland
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7
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Bonnans C, Mainprice B, Chanez P, Bousquet J, Urbach V. Lipoxin A4 stimulates a cytosolic Ca2+ increase in human bronchial epithelium. J Biol Chem 2003; 278:10879-84. [PMID: 12500974 DOI: 10.1074/jbc.m210294200] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Lipoxins are biologically active eicosanoids possessing anti-inflammatory properties. Using a calcium imaging system we investigated the effect of lipoxin A(4) (LXA(4)) on intracellular [Ca(2+)] ([Ca(2+)](i)) of human bronchial epithelial cell. Exposure of the cells to LXA(4) produced a dose-dependent increase in [Ca(2+)](i) followed by a recovery to basal values in primary culture and in 16HBE14o(-) cells. The LXA(4)-induced [Ca(2+)](i) increase was completely abolished after pre-treatment of the 16HBE14o(-) cells with pertussis toxin (G-protein inhibitor). The [Ca(2+)](i) response was not affected by the removal of external [Ca(2+)] but completely inhibited by thapsigargin (Ca(2+)-ATPase inhibitor) treatment. Pre-treatment of the bronchial epithelial cells with either MDL hydrochloride (adenylate cyclase inhibitor) or (R(p))-cAMP (cAMP-dependent protein kinase inhibitor) inhibited the Ca(2+) response to LXA(4). However, the response was not affected by chelerytrine chloride (protein kinase C inhibitor) or montelukast (cysteinyl leukotriene receptor antagonist). The LXA(4) receptor mRNA was detected, by RT-PCR, in primary culture of human bronchial epithelium and in immortalized 16HBE14o(-) cells. The functional consequences of the effect of LXA(4) on intracellular [Ca(2+)](i) have been investigated on Cl(-) secretion, measured using the short-circuit techniques on 16HBE14o(-) monolayers grown on permeable filters. LXA(4) produced a sustained stimulation of the Cl(-) secretion by 16HBE14o(-) monolayers, which was inhibited by BAPTA-AM, a chelator of intracellular calcium. Taken together our results provided evidence for the stimulation of a [Ca(2+)](i) increase by LXA(4) through a mechanism involving its specific receptor and protein kinase A activation and resulting in a subsequent Ca(2+)-dependent Cl(-) secretion by human airway epithelial cells.
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Affiliation(s)
- Caroline Bonnans
- INSERM U454, Department of Respiratory Disease, Centre Hospitalier Universitaire Arnaud de Villeneuve, 34295 Montpellier Cedex 05, France
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Fierro IM, Serhan CN. Mechanisms in anti-inflammation and resolution: the role of lipoxins and aspirin-triggered lipoxins. Braz J Med Biol Res 2001; 34:555-66. [PMID: 11323741 DOI: 10.1590/s0100-879x2001000500002] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Multicellular host responses to infection, injury or inflammatory stimuli lead to the formation of a broad range of chemical mediators by the host. The integrated response of the host is essential to health and disease; thus it is important to achieve a more complete understanding of the molecular and cellular events governing the formation and actions of endogenous mediators of resolution that appear to control the duration of inflammation. Lipoxins are trihydroxytetraene-containing lipid mediators that can be formed during cell-cell interactions and are predominantly counterregulators of some well-known mediators of inflammation. Since this circuit of lipoxin formation and action appears to be of physiological relevance for the resolution of inflammation, therapeutic modalities targeted at this system are likely to have fewer unwanted side effects than other candidates and current anti-inflammatory therapies. Here, we present an overview of the recent knowledge about the biosynthesis and bioactions of these anti-inflammatory lipid mediators.
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Affiliation(s)
- I M Fierro
- Center for Experimental Therapeutics and Reperfusion Injury, Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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Gebhard F, Marzinzig M, Brückner UB, Hartel W. Systemische Freisetzung von Prostanoiden nach chirurgisch induzierter Verletzung des Lungengewebes. Langenbecks Arch Surg 1997. [DOI: 10.1007/bf02395727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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10
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Serhan CN. Lipoxins and novel aspirin-triggered 15-epi-lipoxins (ATL): a jungle of cell-cell interactions or a therapeutic opportunity? PROSTAGLANDINS 1997; 53:107-37. [PMID: 9112289 DOI: 10.1016/s0090-6980(97)00001-4] [Citation(s) in RCA: 178] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Lipid-derived mediators play critical roles in inflammation and other multicellular vascular processes, including atherosclerosis and thrombosis. The lipoxins (LXs) were first isolated in 1984, and have continued to show intriguing and potentially important biological roles. These compounds carry a trihydroxytetraene structure and are both structurally and functionally unique among arachidonic acid-derived bioactive products. The availability of synthetic materials for evaluation of bioactions as well as appropriate methods of detection to determine when and where LX are generated has, in recent studies, catapulted our understanding of the formation and actions of the lipoxins. This mini-review addresses new concepts in the formation and biological roles of these lipid-derived mediators and considers whether the lipoxins and the newly discovered aspirin-triggered lipoxins (ATL) represent novel approaches for therapeutic opportunities. Recent findings indicate that select cytokines and aspirin initiate and regulate LX biosynthetic events. These circuits involve cell-cell interfacing that facilitates transcellular events to form LX that display anti-inflammatory actions in both in vitro and in vivo models. These recent results suggest that LX biosynthetic circuits assemble to evoke anti-inflammatory actions and generate LX that can serve as "stop signals" in appropriate microenvironments.
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Affiliation(s)
- C N Serhan
- Center for Experimental Therapeutics and Reperfusion Injury, Brigham, and Women's Hospital, Boston, Massachusetts 02115, USA
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11
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Leszczynski D, Fagerholm S, Leszczynski K. The effects of the broadband UVA radiation on myeloid leukemia cells: the possible role of protein kinase C in mediation of UVA-induced effects. Photochem Photobiol 1996; 64:936-42. [PMID: 8972634 DOI: 10.1111/j.1751-1097.1996.tb01858.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We examined the effects of broadband UVA radiation (320-400 nm) on a rat myeloid leukemia cell line-chloroma (ChL). A Phillips face tanner model HB 171/A was used as a light source. Chloroma were irradiated through a 5 mm thick glass filter that cut off all of the UVB contamination. The irradiances were measured, from 250 to 400 nm, with a well-characterized and calibrated double-grating spectroradiometer Optronic 742. The overall uncertainty of dose evaluation was estimated to be +/-15% (2 sigma). The cells were irradiated with UVA doses of 4 and 8 J/cm2 and cultured thereafter for 24 h. After this period of time, a marked decline up to 50% was observed in cell proliferation in UVA-irradiated ChL cultures. The cell proliferation decline was found to be caused by simultaneously occurring G2/M phase cell cycle arrest and apoptosis in part of the UVA-irradiated ChL population. Concomitantly, with the decline in cell proliferation, an increase was observed in the expression of the major histocompatibility (MHC) class I and II antigens. Because protein kinase C (PKC) is known to regulate cell proliferation, apoptosis and expression of MHC antigens, and because UVA was shown to regulate PKC activity/expression, we therefore examined whether UVA irradiation has any effect on the expression of isozymes of PKC. Western blots revealed that ChL express alpha, beta I, delta, epsilon, eta, and zeta/iota isozymes of PKC and that expression of all isozymes declined 24 h after UVA irradiation (8 J/cm2). Finally, PKC activation in ChL by exposure to phorbol ester caused cell cycle arrest in G1 phase but did not induce apoptosis. This suggests that the previously shown UVA-induced PKC activation in ChL might be responsible for the induction of MHC antigens but the simultaneously observed ChL apoptosis is likely to be mediated by PKC down-regulation. All together, our results suggest that UVA, at irradiance levels that resemble the outdoor exposure, may have profound effects on the immune-related properties of leukocytes. Thus, we speculate that in vivo the immune functions of leukocytes passing through dermal capillaries might be altered by exposure to solar UVA radiation.
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Affiliation(s)
- D Leszczynski
- Radiobiology Laboratory, Finnish Centre for Radiation and Nuclear Safety, Helsinki, Finland.
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12
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Serhan CN, Romano M. Lipoxin biosynthesis and actions: role of the human platelet LX-synthase. JOURNAL OF LIPID MEDIATORS AND CELL SIGNALLING 1995; 12:293-306. [PMID: 8777573 DOI: 10.1016/0929-7855(95)00035-o] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- C N Serhan
- Center for Experimental Therapeutics & Reperfusion Injury, Brigham and Women's Hospital, Boston, MA 02115, USA
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13
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Leszczynski D, Leszczynski K, Servomaa K. Long-wave ultraviolet radiation causes increase of membrane-bound fraction of protein kinase C in rat myeloid leukemia cells. PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE 1995; 11:124-30. [PMID: 8555011 DOI: 10.1111/j.1600-0781.1995.tb00151.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We examined the effect of long-wave ultraviolet radiation (UVA) on protein kinase C (PKC) and on the proliferation of rat myeloid leukemia cell line (ChL). Exposure of cells to a single dose of UVA (8 J/cm2 at 372 +/- 10 nm) caused a rapid increase in the quantity of the membrane-bound PKC, as assessed by 3H-phorbol ester (3H-PMA) binding assay (performed at 4 degrees C). Within 2 h of UVA irradiation, three peaks of increased 3H-PMA binding to the ChL cells (by 70-100%) were observed at ca. 20, 60 and 95 min post-irradiation. The exposure of ChL to UVA caused also a rapid, but transient, decline in the cell proliferation rate (by 18% within 24 h). However, the statistically significant decrease in cell numbers was observed only 3 days later (down by 22%). The inhibition of ChL proliferation was not due to alteration of cell viability as determined by trypan blue exclusion assay, and neither was it caused by cell cycle arrest or apoptosis, as determined by flow cytometry analysis of propidium iodide-labelled cells and cell morphology in May-Grünvald-Giemsa-stained cell smears. Phorbol-ester-induced activation of PKC (performed at 37 degrees C) caused inhibition of ChL proliferation similar to that caused by UVA. This suggests that a UVA-induced increase of the membrane-bound fraction of PKC may be responsible for the UVA-induced inhibition of ChL proliferation.
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Affiliation(s)
- D Leszczynski
- Laboratory of Radiobiology, Finnish Centre for Radiation and Nuclear Safety, Helsinki, Finland
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14
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Serhan CN. Lipoxin biosynthesis and its impact in inflammatory and vascular events. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1212:1-25. [PMID: 8155718 DOI: 10.1016/0005-2760(94)90185-6] [Citation(s) in RCA: 222] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- C N Serhan
- Department of Medicine, Brigham and Women's Hospital, Boston, MA
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Xu J, Qu ZX, Moore SA, Hsu CY, Hogan EL. Receptor-linked hydrolysis of phosphoinositides and production of prostacyclin in cerebral endothelial cells. J Neurochem 1992; 58:1930-5. [PMID: 1313855 DOI: 10.1111/j.1471-4159.1992.tb10071.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The receptor agonist-mediated hydrolysis of phosphoinositides and production of prostacyclin were studied in murine cerebral endothelial cells (MCEC). Of 11 neurotransmitters and neuromodulators examined, carbachol, noradrenaline (NE), bradykinin, and thrombin significantly increased 3H-inositol phosphate accumulation in the presence of LiCl (20 mM). The maximal stimulation of [3H]inositol monophosphate ([3H]IP1) reached approximately 11, 11, seven, and four times the basal levels for carbachol, NE, bradykinin, and thrombin, respectively. The EC50 values of IP1 accumulation for carbachol and NE were 34 and 0.16 microM, respectively. The muscarinic antagonists, atropine and pirenzepine, blocked the carbachol-induced IP1 accumulation with Ki values of 0.3 and 30 nM, respectively. The adrenergic antagonist, prazosin, blocked NE-induced IP1 accumulation with a Ki of 0.1 nM. The calcium ionophore A23187, histamine, glutamate, vasopressin, serotonin, platelet activating factor, and substance P did not stimulate IP1 accumulation. A23187, bradykinin, and thrombin stimulated prostacyclin release to approximately four, four, and two times the basal levels, respectively, whereas carbachol and NE had little effect upon prostacyclin release. These results suggest that the activation of phospholipase C and of phospholipase A2 in MCEC are regulated separately.
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Affiliation(s)
- J Xu
- Department of Neurology, Medical University of South Carolina, Charleston 29425
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