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Azad GK, Tomar RS. Ebselen, a promising antioxidant drug: mechanisms of action and targets of biological pathways. Mol Biol Rep 2014; 41:4865-79. [DOI: 10.1007/s11033-014-3417-x] [Citation(s) in RCA: 196] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Toxicology and pharmacology of selenium: emphasis on synthetic organoselenium compounds. Arch Toxicol 2011; 85:1313-59. [DOI: 10.1007/s00204-011-0720-3] [Citation(s) in RCA: 330] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Accepted: 05/18/2011] [Indexed: 02/07/2023]
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Nogueira CW, Zeni G, Rocha JBT. Organoselenium and Organotellurium Compounds: Toxicology and Pharmacology. Chem Rev 2004; 104:6255-85. [PMID: 15584701 DOI: 10.1021/cr0406559] [Citation(s) in RCA: 1429] [Impact Index Per Article: 71.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Cristina W Nogueira
- Laboratório de Síntese, Reatividade e Avaliacão Farmacológica e Toxicológica de Organocalcogênios, CCNE, UFSM, Santa Maria, CEP 97105-900 Rio Grande do Sul, Brazil
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Ohta Y, Kobayashi T, Inui K, Yoshino J, Nakazawa S. Protective effect of ebselen, a seleno-organic compound, against the progression of acute gastric mucosal lesions induced by compound 48/80, a mast cell degranulator, in rats. JAPANESE JOURNAL OF PHARMACOLOGY 2002; 90:295-303. [PMID: 12501005 DOI: 10.1254/jjp.90.295] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The protective effect of ebselen, which possesses glutathione peroxidase-like activity and antioxidative and anti-inflammatory properties, against the progression of acute gastric mucosal lesions was examined in rats with a single intraperitoneal injection of compound 48/80 (0.75 mg/kg). Ebselen (50, 100 or 200 mg/kg) was orally administered 0.5 h after compound 48/80 treatment, at which time gastric mucosal lesions appeared. Post-administered ebselen suppressed gastric mucosal lesion progression at 3 h after compound 48/80 treatment dose-dependently, although no dose of ebselen affected the decreased gastric mucosal blood flow and increased serum serotonin and histamine concentrations found at 3 h after the treatment. A decrease in Se-glutathione peroxidase activity and increases in myeloperoxidase and xanthine oxidase activities and the concentration of thiobarbituric acid reactive substances were found in gastric mucosal tissues at 0.5 h after compound 48/80 treatment, and these changes were further enhanced at 3 h. Post-administered ebselen attenuated all these changes found at 3 h after compound 48/80 treatment dose-dependently. The present results indicate that ebselen exerts a protective effect against the progression of compound 48/80-induced acute gastric mucosal lesions in rats, and they suggest that this protective effect of ebselen could be due to its glutathione peroxidase-like activity and its antioxidative and anti-inflammatory properties.
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Affiliation(s)
- Yoshiji Ohta
- Department of Chemistry, School of Medicine, Fujita Health University, Toyoake, Aichi, Japan.
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Haddad EB, McCluskie K, Birrell MA, Dabrowski D, Pecoraro M, Underwood S, Chen B, De Sanctis GT, Webber SE, Foster ML, Belvisi MG. Differential effects of ebselen on neutrophil recruitment, chemokine, and inflammatory mediator expression in a rat model of lipopolysaccharide-induced pulmonary inflammation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 169:974-82. [PMID: 12097404 DOI: 10.4049/jimmunol.169.2.974] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We postulated that the seleno-organic compound ebselen would attenuate neutrophil recruitment and activation after aerosolized challenge with endotoxin (LPS) through its effect as an antioxidant and inhibitor of gene activation. Rats were given ebselen (1-100 mg/kg i.p.) followed by aerosolized LPS exposure (0.3 mg/ml for 30 min). Airway inflammatory indices were measured 4 h postchallenge. Bronchoalveolar lavage (BAL) fluid cellularity and myeloperoxidase activity were used as a measure of neutrophil recruitment and activation. RT-PCR analysis was performed in lung tissue to assess gene expression of TNF-alpha, cytokine-induced neutrophil chemoattractant-1 (CINC-1), macrophage-inflammatory protein-2 (MIP-2), ICAM-1, IL-10, and inducible NO synthase. Protein levels in lung and BAL were also determined by ELISA. Ebselen pretreatment inhibited neutrophil influx and activation as assessed by BAL fluid cellularity and myeloperoxidase activity in cell-free BAL and BAL cell homogenates. This protective effect was accompanied by a significant reduction in lung and BAL fluid TNF-alpha and IL-1 beta protein and/or mRNA levels. Ebselen pretreatment also prevented lung ICAM-1 mRNA up-regulation in response to airway challenge with LPS. This was not a global effect of ebselen on LPS-induced gene expression, because the rise in lung and BAL CINC-1 and MIP-2 protein levels were unaffected as were lung mRNA expressions for CINC-1, MIP-2, IL-10, and inducible NO synthase. These data suggest that the anti-inflammatory properties of ebselen are achieved through an inhibition of lung ICAM-1 expression possibly through an inhibition of TNF-alpha and IL-1 beta, which are potent neutrophil recruiting mediators and effective inducers of ICAM-1 expression.
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Affiliation(s)
- El-Bdaoui Haddad
- Department of Pharmacology, Aventis Pharma, Bridgewater, NJ, 08807-0800, USA.
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Kobayashi T, Ohta Y, Yoshino J. Preventive effect of ebselen on acute gastric mucosal lesion development in rats treated with compound 48/80. Eur J Pharmacol 2001; 414:271-9. [PMID: 11239928 DOI: 10.1016/s0014-2999(01)00815-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The preventive effect of ebselen, a seleno-organic compound, which is known to possess glutathione peroxidase-like activity and antioxidative and anti-inflammatory properties, on the development of acute gastric mucosal lesions was examined in rats with a single injection of compound 48/80 (0.75 mg/kg, i.p.), a mast cell degranulator. Pre-administration of ebselen (p.o.) at a dose of 50 or 100 mg/kg, but not 10 mg/kg, prevented gastric mucosal lesion development at 3 h, but not gastric mucosal lesion formation at 0.5 h, after compound 48/80 injection, although any dose of pre-administered ebselen did not affect decreased gastric mucosal blood flow and increased serum serotonin and histamine concentrations found at 0.5 and 3 h after compound 48/80 injection. A decrease in Se-glutathione peroxidase activity and increases in the activities of myeloperoxidase, an index of tissue neutrophil infiltration, and xanthine oxidase and the concentration of thiobarbituric acid reactive substances, an index of lipid peroxidation, were found in gastric mucosal tissues at 0.5 h after compound 48/80 injection and these changes were further enhanced at 3 h. Pre-administration of ebselen (p.o.) at a dose of 50 or 100 mg/kg, but not 10 mg/kg, attenuated all these changes found at 3 h after compound 48/80 injection. These preventive effects of ebselen occurred in a dose-dependent manner. The present results indicate that pre-administered ebselen prevents the development of compound 48/80-induced acute gastric mucosal lesions in rats, and suggest that this preventive effect of ebselen could be due to its glutathione peroxidase-like activity and antioxidative and anti-inflammatory properties.
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Affiliation(s)
- T Kobayashi
- Department of Internal Medicine, Second Teaching Hospital, School of Medicine, Fujita Health University, Otobashi, Nakagawa-ku, Aichi 454-0012, Nagoya, Japan
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Moutet M, d'Alessio P, Malette P, Devaux V, Chaudière J. Glutathione peroxidase mimics prevent TNFalpha- and neutrophil-induced endothelial alterations. Free Radic Biol Med 1998; 25:270-81. [PMID: 9680172 DOI: 10.1016/s0891-5849(98)00038-0] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Based on the assumption that glutathione peroxidase (GPx) activity might be limiting in preventing peroxide-induced impairment of endothelial regulatory functions, we studied the effect of a series of new selenium-containing GPx mimics on endothelial cells exposed to an inflammatory stress. The two compounds that have the highest GPx activity, BXT-51072 and BXT-51077, were shown to be the most efficient inhibitors of leukocyte recruitment by human umbilical vein endothelial cells (HUVEC), upon incubation with neutrophils (10-fold excess over HUVEC) and with 1 ng/ml TNF-alpha for 1 or 3.5 h. When HUVEC were pre- and cotreated with 10 microM of either compound, neutrophil adhesion and endothelial alteration were markedly inhibited, as assessed by immunoassays of myeloperoxidase and von Willebrand factor, respectively. These two GPx mimics were also found to be the most efficient inhibitors of the TNFalpha-induced endothelial expression of P- and E-selectin and of the TNFalpha- or interleukin1-induced endothelial release of interleukin-8. Our results demonstrate that GPx mimics such as BXT-51072 behave as potent antagonists of TNF-alpha and interleukin-1 through the downregulation of endothelial proinflammatory responses.
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Affiliation(s)
- M Moutet
- Centre de Recherche Oxis International SA, Bonneuil-sur-Marne, France
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Takasago T, Peters EE, Graham DI, Masayasu H, Macrae IM. Neuroprotective efficacy of ebselen, an anti-oxidant with anti-inflammatory actions, in a rodent model of permanent middle cerebral artery occlusion. Br J Pharmacol 1997; 122:1251-6. [PMID: 9401794 PMCID: PMC1565026 DOI: 10.1038/sj.bjp.0701426] [Citation(s) in RCA: 128] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
1. The aim of this study was to investigate whether delayed treatment with the anti-oxidant and anti-inflammatory agent ebselen reduces the volume of infarction in a rodent model of permanent focal cerebral ischaemia. 2. Ebselen (10 or 30 mg kg-1) or vehicle was administered by gavage 30 min and 12 h after the induction of cerebral ischaemia by permanent occlusion of the left middle cerebral artery (MCA). Animals were killed 24 h following MCA occlusion, and the volumes of ischaemic damage in the ebselen and control groups were evaluated by quantitative histopathology. 3. Ebselen was quickly absorbed following oral (gavage) administration and reached peak levels in the plasma by 1 h post-administration (plasma selenium level of 0.68 +/- 0.04 and 0.84 +/- 0.1 microgram ml-1 for 10 and 30 mg kg-1, respectively, compared to control level of 0.51 +/- 0.02 microgram kg-1). 4. Treatment with the lower dose of ebselen (10 mg kg-1) significantly (P < 0.01) reduced the volume of infarction in the cerebral hemisphere and cerebral cortex (by 31.8% and 36.7%, respectively compared with the placebo group). 5. The neuroprotective efficacy of the higher dose ebselen (30 mg kg-1) was less than that of the lower dose ebselen (10 mg kg-1). The volume of ischaemic damage in the cerebral hemisphere was reduced by 23.7% (P < 0.02), and cerebral cortex by 27.5% (P < 0.01). 6. Both doses of ebselen (10, 30 mg kg-1) had no therapeutic efficacy on the caudate nucleus, where ischaemia was most severe, in this model. 7. Free radical-mediated injury is normally associated with reperfusion of ischaemic tissue. The present results suggest that oxidative injury is also a significant contributor to brain damage in models of maintained (permanent) ischaemia and that ebselen is effective in attenuating this free radical-induced damage.
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Affiliation(s)
- T Takasago
- Wellcome Surgical Institute & Hugh Fraser Neuroscience Labs., University of Glasgow
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Komatsu H, Amano M, Chiba K, Okumoto T. Inhibition of Mac-1-dependent leukocyte adhesion by Y-24180, an anti-inflammatory agent, in mice. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 1996; 1:91-96. [PMID: 21781667 DOI: 10.1016/1382-6689(95)00014-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/1995] [Revised: 09/05/1995] [Accepted: 10/25/1995] [Indexed: 05/31/2023]
Abstract
Y-24180 (4-(2-chlorophenyl)-2-[2-(4-isobutylphenyl)ethyl]-6,9-dimethyl-6H-thieno[3,2-f][1,2,4]triazolo[4,3-a][1,4]-diazepine), an antagonist of platelet-activating factor (PAF), has been already clarified to suppress the expression of an adhesion molecule, Mac-1, on human neutrophils in the previous in vitro study. In the present paper, we examined the effect of Y-24180 on in vivo Mac-1 expression on mouse neutrophils using a lipopolysaccharide-induced leukocyte reduction model in which Mac-1-dependent infiltration of neutrophils was involved. Prophylactic oral administration of Y-24180 inhibited the induction of Mac-1-strongly positive neutrophils by intraperitoneal injection of lipopolysaccharide and prevented the reduction of leukocyte number. In contrast, WEB 2086 (3-[4-(2-chlorophenyl)-9-methyl-6H-thieno[3,2-f][1,2,4]triazolo[4,3-a][1,4]diazepine-2-yl]-1-(4-morpholinyl)-1-propanone), another PAF antagonist, showed little effect. PAF injection failed to induce the Mac-1-strongly positive neutrophils in peripheral blood and the reduction of circulating leukocytes, indicating that PAF was not concerned with the lipopolysaccharide-induced up-regulation of Mac-1 expression and leukocyte reduction. Y-24180 inhibited the leukocyte infiltration also in the thioglycollate medium-induced peritonitis, which was mediated by Mac-1-dependent leukocyte adhesion. These results indicate that Y-24180 inhibits the leukocyte infiltration into the inflamed sites by suppressing Mac-1 expression on leukocytes in vivo and can contribute to the improvement of inflammatory diseases in which the Mac-1-dependent leukocyte adhesion is involved.
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Affiliation(s)
- H Komatsu
- Research Laboratories, Yoshitomi Pharmaceutical Industries, Ltd., 7-25, Koyata 3-chome, Iruma-shi, Saitama 358 Japan
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Abstract
1. Ebselen (2-phenyl-1,2-benzisoselenazol-3(2H)-one) is a non-toxic seleno-organic drug with antiinflammatory, antiatherosclerotic and cytoprotective properties. 2. Ebselen and some of its metabolites are effective reductants of hydroperoxides including those arising in biomembranes and lipoproteins. 3. By reactions with hydroperoxides and thiols several interconversion cycles are formed which include ebselen metabolites with varying oxidation number of the selenium. 4. In the presence of thiols ebselen mimics the catalytic activities of phospholipid hydroperoxide glutathione peroxidase. 5. Ebselen inhibits at low concentrations a number of enzymes involved in inflammation such as lipoxygenases, NO synthases, NADPH, oxidase, protein kinase C and H+/K(+)-ATPase. The inhibitions are manifested on the cellular level and may contribute to the antiinflammatory potential of ebselen.
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Affiliation(s)
- T Schewe
- Institute of Biochemistry, University Clinics Charité, Humboldt University of Berlin, Germany
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Gao JX, Issekutz AC. The effect of ebselen on T-lymphocyte migration to arthritic joints and dermal inflammatory reactions in the rat. INTERNATIONAL JOURNAL OF IMMUNOPHARMACOLOGY 1994; 16:279-87. [PMID: 8045667 DOI: 10.1016/0192-0561(94)90002-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We have previously observed that ebselen (PZ 51, 2-Phenyl-1,2-Bensoisoselenazol-3-(2H)-one) can inhibit human polymorphonuclear leukocyte (PMNL) transendothelial migration in vitro and PMNL migration to arthritic joints and dermal inflammatory reactions in rats. In this study, we investigated the effect of ebselen on T-lymphocyte migration to the inflamed joints in rats with adjuvant arthritis (AA) and to dermal inflammation induced by cytokines (IFN gamma, mTNF alpha), cytokine inducing stimuli (poly I:C and LPS), or a delayed type hypersensitivity (DTH) reaction. Treatment of rats with AA with ebselen (100 mg/kg/day) p.o. for three days significantly reduced accumulation of 111In-labelled spleen T-cells (SPLT) in the arthritic joints, including forepaws, carpal joints, hindpaws and talar joints, and in all the above dermal inflammatory reactions. The inhibitory effect of ebselen on SPLT cell accumulation was greater than with indomethacin (2 mg/kg/day) and was observed within 3 h of initiation of ebselen treatment. Ebselen also inhibited SPLT migration to mandibular, axillary and mesenteric lymph nodes, and to the spleen. The results suggest that not only does ebselen inhibit SPLT migration to inflamed joints and to dermal inflammation but it also may inhibit lymphocyte homing and recirculation. Whether these effects of ebselen are related to its reported inhibition of cellular activation and intracellular signalling requires further investigation. However, the inhibition of T-lymphocyte migration reported here and of PMNL migration reported previously may both be beneficial in the treatment of human arthritis.
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Affiliation(s)
- J X Gao
- Department of Pediatrics and Microbiology-Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
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Patrick RA, Peters PA, Issekutz AC. Ebselen is a specific inhibitor of LTB4-mediated migration of human neutrophils. AGENTS AND ACTIONS 1993; 40:186-90. [PMID: 8023742 DOI: 10.1007/bf01984060] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Ebselen is a seleno-organic anti-inflammatory compound with glutathione peroxidase-like activity that has the unique characteristic of mediating the isomerization of 5-HETE and LTB4 to their biologically inactive trans isomers, both directly in fluid phase and indirectly through metabolic pathways in stimulated peripheral blood leukocytes. LTB4 is an inflammatory mediator with potent chemotactic activity for neutrophilic leukocytes. We studied the effects of ebselen on the chemotactic and chemokinetic responses with human-blood-derived neutrophils. With the use of 120-microns-thick 5-microns-pore durapore filters and low BSA concentrations (0.05%) in the chemotaxis buffers, ebselen was evaluated for its effect on both chemotactic and chemokinetic responses to LTB4, C5a, and fMLP. Ebselen at 3-20 microM concentrations inhibited both chemotactic and chemokinetic responses to optimal concentrations of LTB4 without altering chemotactic responses to C5a or fMLP. Likewise, ebselen at 20 microM specifically inhibited LTB4-stimulated transendothelial migration of neutrophils, while not altering responses to C5a nor fMLP.
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Affiliation(s)
- R A Patrick
- CIBA-GEIGY Corporation, Pharmaceuticals Division, Department of IOE/Research, Summit, NJ 07901
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Gao JX, Issekutz AC. The effect of ebselen on polymorphonuclear leukocyte migration to joints in rats with adjuvant arthritis. INTERNATIONAL JOURNAL OF IMMUNOPHARMACOLOGY 1993; 15:793-802. [PMID: 8262693 DOI: 10.1016/0192-0561(93)90016-r] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We have previously reported that ebselen (PZ 51,2-Phenyl-1,2- Benzoisoselenazol-3-(2H)-one), a selinyl organic compound with anti-inflammatory properties, inhibited human polymorphonuclear leukocyte (PMNL) adhesion to and migration through cytokine-activated human umbilical vein endothelium in vitro. Here we investigated the in vivo effect of ebselen on PMNL migration into arthritic joints and dermal inflammation in rats with adjuvant arthritis. The rats were immunized with adjuvant (Mycobacteriaum butyricum in mineral oil) and 13 days later, when arthritis was fully developed, treatment (p.o.) with ebselen, indomethacin or vehicle was initiated. The migration of 51Cr-labelled blood PMNL purified from arthritic donors and extravasation of 125I-labelled HSA in arthritic joints and dermal inflammatory reactions was quantitatively measured. Treatment of rats with 100 mg/kg/day ebselen for 3 days, inhibited by 72-79% the PMNL migration into arthritic joints and tail (spondylitis) and by 50-60% into dermal inflammatory reactions induced with zymosan-activated rat serum (ZAS; C5adesArg), endotoxin (LPS) or IL-1 alpha. The inhibitory effect of ebselen was dose-dependent, because treatment of rats with 100 mg/kg/day ebselen caused significantly more inhibition of PMNL migration than did 30 mg/kg/day, although this dose was still effective. Ebselen inhibited PMNL migration into arthritic joints and dermal inflammation within 3 h of initial oral administration (100 mg/kg). However, ebselen did not suppress plasma albumin extravasation into arthritic joints and dermal inflammatory reactions. Compared to ebselen, treatment with indomethacin (2 mg/kg/day) was significantly less effective in inhibiting PMNL accumulation in joints, but in contrast to ebselen, indomethacin did inhibit plasma albumin extravasation into carpal and talar joints. The results suggest that ebselen effectively and rapidly inhibits PMNL migration in vivo, as also observed in vitro, and that it has anti-inflammatory actions distinct from classic nonsteroidal anti-inflammatory drugs such as indomethacin.
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Affiliation(s)
- J X Gao
- Department of Pediatrics, Dalhousie University, Halifax, Nova Scotia, Canada
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Gao JX, Issekutz AC. The effect of ebselen on polymorphonuclear leukocyte and lymphocyte migration to inflammatory reactions in rats. IMMUNOPHARMACOLOGY 1993; 25:239-51. [PMID: 8354640 DOI: 10.1016/0162-3109(93)90052-r] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Ebselen, a selinyl organic compound with anti-inflammatory properties was found by us previously to inhibit in vitro human polymorphonuclear leukocyte (PMNL) adhesion to and migration through umbilical vein endothelium monolayers. Here we investigated in rats the effect of ebselen on PMNL and spleen T lymphocyte (SPLT) migration to inflamed joints induced by intra-articular (i.a) injection of recombinant murine tumor necrosis factor alpha (mTNF alpha) and to dermal inflammatory reactions. Inflammation was induced in the carpal and talar joints of rats by intra-articular (i.a.) injection (100 ng) of mTNF alpha once daily for 2 days. Corresponding joints in the opposite limb received diluent. Simultaneously, the rats were treated p.o. with either ebselen (100 mg/kg/day) or indomethacin (2 mg/kg/day) or vehicle for 2 days. Dermal inflammation was induced by intradermal injection (0.05 ml) of inflammatory stimuli. Accumulation of 51Cr-labelled rat blood PMNL, 111In-labeled SPLT, and extravasation of 125I-labelled human serum albumin (HSA) in the joints and in skin sites were measured. Treatment of rats with ebselen inhibited by 33-65% PMNL migration to the mTNF alpha inflamed joints, and to dermal inflammation induced by zymosan activated serum (ZAS; containing C5adesArg), endotoxin (LPS), mIL-1 beta and mTNF alpha. Migration of SPLT to dermal inflammation induced by interferon gamma (IFN gamma), poly-inosine-cytosine (poly I:C) and LPS was also significantly inhibited (22-33%), but SPLT migration into the inflamed joints was not effected by ebselen. Indomethacin treatment of rats also inhibited PMNL migration into the inflamed joints, but unlike ebselen, indomethacin inhibited only ZAS induced dermal PMNL accumulation. In contrast to ebselen, indomethacin inhibited SPLT migration into the inflamed joints as well as to the dermal inflammation induced by poly I:C and a delayed-type hypersensitivity reaction (DTH). In addition, treatment of rats with indomethacin significantly inhibited plasma protein (125I-HSA) extravasation in the inflamed joints and the dermal inflammatory reaction induced by ZAS, but ebselen had no such effect. In conclusion, ebselen appears to have a distinct antiinflammatory mechanism of action from indomethacin and the PMNL findings are consistent with a direct inhibitory action on PMNL activation and PMNL transendothelial migration as observed previously in vitro.
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Affiliation(s)
- J X Gao
- Department of Pediatrics and Microbiology-Immunology, Dalhousie University, Halifax, N.S., Canada
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