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Ryan AF, Bakaletz LO, Juhn SK, Jung TTK, Li JD. 5. Molecular Biology and Biochemistry. Ann Otol Rhinol Laryngol 2016. [DOI: 10.1177/00034894021110s308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Ogra PL, Barenkamp SJ, DeMaria TF, Bakaletz LO, Chonmaitree T, Heikkinen T, Hurst DS, Kawauchi H, Kurono Y, Patel JA, Sih TM, Stenfors LE, Suzuki M. 6. Microbiology and Immunology. Ann Otol Rhinol Laryngol 2016. [DOI: 10.1177/00034894021110s309] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Nakamura Y, Hamajima Y, Suzuki M, Esaki S, Yokota M, Oshika M, Takagi I, Yasui K, Miyamoto N, Sugiyama K, Nakayama M, Murakami S. The effect of the leukotriene antagonist pranlukast on pediatric acute otitis media. Int J Pediatr Otorhinolaryngol 2016; 87:34-8. [PMID: 27368439 DOI: 10.1016/j.ijporl.2016.05.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 05/11/2016] [Accepted: 05/12/2016] [Indexed: 10/21/2022]
Abstract
OBJECTIVE Conventional treatment for acute otitis media mainly targets bacteria with antibiotics, neglecting to control for mediators of inflammation. Mediators of inflammation, such as leukotrienes, have been identified in patients with acute otitis media (AOM) or subsequent secretory otitis media (SOM). They can cause functional eustachian tube dysfunction or increase mucous in the middle ear, causing persistent SOM following AOM. The objective of the present study was to evaluate whether or not administration of pranlukast, a widely used leukotriene C4, D4, and E4 antagonist, together with antibiotics could inhibit the progression to SOM. METHODS Children with AOM, who were from two to 12 years old, were randomly divided into two groups as follows: a control group in which 50 patients received antibiotic-based conventional treatment according to guidelines for treating AOM proposed by the Japan Otological Society (version 2006); and a pranlukast group, in which 52 patients were administered pranlukast for up to 28 days as well as given conventional treatment. Cases were regarded as persistent SOM when a tympanogram was type B or C2 four weeks after treatment was initiated. RESULTS Two patients in the pranlukast group and 3 patients in the control group were excluded because they relapsed AOM within 28 days after initial treatment. Therefore, the analysis included 50 and 47 subjects in the pranlukast and control groups, respectively. The percentage of patients diagnosed with persistent SOM (22.0%) was significantly smaller in the pranlukast group compared with the control group (44.7%) (p = 0.018, chi-squared test). CONCLUSION The results indicate that combined treatment of AOM with antibiotics and a leukotriene antagonist to control inflammation is useful for preventing progression to persistent SOM.
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Affiliation(s)
- Yoshihisa Nakamura
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan.
| | - Yuki Hamajima
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Motohiko Suzuki
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Shinichi Esaki
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Makoto Yokota
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Masanori Oshika
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Ippei Takagi
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Keiko Yasui
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Naoya Miyamoto
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Kazuko Sugiyama
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Meiho Nakayama
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Shingo Murakami
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
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Santiago RF, de Brito TV, Dias JM, Dias GJ, da Cruz JS, Batista JA, Silva RO, Souza MHLP, de Albuquerque Ribeiro R, Gutierrez SJC, Freitas RM, Medeiros JVR, dos Reis Barbosa AL. Riparin B, a Synthetic Compound Analogue of Riparin, Inhibits the Systemic Inflammatory Response and Oxidative Stress in Mice. Inflammation 2015; 38:2203-15. [DOI: 10.1007/s10753-015-0203-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Dias JM, de Brito TV, de Aguiar Magalhães D, da Silva Santos PW, Batista JA, do Nascimento Dias EG, de Barros Fernandes H, Damasceno SRB, Silva RO, Aragão KS, Souza MHLP, Medeiros JVR, Barbosa ALR. Gabapentin, a Synthetic Analogue of Gamma Aminobutyric Acid, Reverses Systemic Acute Inflammation and Oxidative Stress in Mice. Inflammation 2014; 37:1826-36. [DOI: 10.1007/s10753-014-9913-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Uçar S, Huseynov T, Çoban M, Sarıoğlu S, Serbetçioğlu B, Yalcin AD. Montelukast is as effective as penicillin in treatment of acute otitis media: an experimental rat study. Med Sci Monit Basic Res 2013; 19:246-52. [PMID: 24048018 PMCID: PMC3808231 DOI: 10.12659/msmbr.889474] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Background Leukotrienes are the major factors in the formation of edema and mucus, as well as development of tuba Eustachii dysfunction in acute otitis media. We developed an experimental acute suppurative otitis media model and compared the responses of rats to penicillin and combinations of leukotriene antagonist with respect to histopathological observations conducted in early and late phases. Material/Methods A total of 83 ears from 56 Wistar rats were used in this study. Pneumococcus suspension was injected trans-tympanically into all rats. Subjects were classified into 4 different groups with 14 rats in each. In Group A, intramuscular penicillin G was injected for a period of 5 days. In Group B, intraperitoneal montelukast was injected for 21 days in addition to penicillin. In Group C, intraperitoneal montelukast isotonic NaCl in Group D was injected into rats for 21 days. Results No significant difference was found between the groups, except for mucosal vascularization with respect to mucosal and TM parameters in early phases. Furthermore, considerable deviations were observed for the recuperation of TM and mucosal inflammation for groups in which subjects were injected with montelukast as compared to other groups of the study in the late phases. Conclusions When the parameters of inflammation in the rat middle ear were compared with each other, most of these parameters did not show any statistically significant beneficial effects in montelukast and penicillin groups.
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Affiliation(s)
- Seçil Uçar
- Dokuz Eylul University, Medical School, Department of Otorhinolaryngology, Izmir, Turkey.
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Arab HH, El-Sawalhi MM. Carvedilol alleviates adjuvant-induced arthritis and subcutaneous air pouch edema: modulation of oxidative stress and inflammatory mediators. Toxicol Appl Pharmacol 2013; 268:241-8. [PMID: 23360886 DOI: 10.1016/j.taap.2013.01.019] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Revised: 12/18/2012] [Accepted: 01/13/2013] [Indexed: 10/27/2022]
Abstract
Rheumatoid arthritis (RA) is a systemic inflammatory disease with cardiovascular complications as the leading cause of morbidity. Carvedilol is an adrenergic antagonist which has been safely used in treatment of several cardiovascular disorders. Given that carvedilol has powerful antioxidant/anti-inflammatory properties, we aimed to investigate its protective potential against arthritis that may add further benefits for its clinical usefulness especially in RA patients with concomitant cardiovascular disorders. Two models were studied in the same rat; adjuvant arthritis and subcutaneous air pouch edema. Carvedilol (10mg/kg/day p.o. for 21days) effectively suppressed inflammation in both models with comparable efficacy to the standard anti-inflammatory diclofenac (5mg/kg/day p.o.). Notably, carvedilol inhibited paw edema and abrogated the leukocyte invasion to air pouch exudates. The latter observation was confirmed by the histopathological assessment of the pouch lining that revealed mitigation of immuno-inflammatory cell influx. Carvedilol reduced/normalized oxidative stress markers (lipid peroxides, nitric oxide and protein thiols) and lowered the release of inflammatory cytokines (TNF-α & IL-6), and eicosanoids (PGE2 & LTB4) in sera and exudates of arthritic rats. Interestingly, carvedilol, per se, didn't present any effect on assessed biochemical parameters in normal rats. Together, the current study highlights evidences for the promising anti-arthritic effects of carvedilol that could be mediated through attenuation of leukocyte migration, alleviation of oxidative stress and suppression of proinflammatory cytokines and eicosanoids.
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Affiliation(s)
- Hany H Arab
- Biochemistry Division, Department of Pharmacology and Toxicology, Faculty of Pharmacy, Taif University, Taif, Saudi Arabia.
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Sütbeyaz Y, Aktan B, Yoruk O, Özdemir H, Gundogdu C. Treatment of Sinusitis with Corticosteroids in Combination with Antibiotics in Experimentally Induced Rhinosinusitis. Ann Otol Rhinol Laryngol 2008; 117:389-94. [DOI: 10.1177/000348940811700510] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objectives: The objective of this study was to investigate the effects of corticosteroids, antibiotics, and their combination in the therapy of experimental bacterial rhinosinusitis. Methods: Twenty-eight rabbits underwent experimental induction of bacterial rhinosinusitis with Staphylococcus aureus. The animals were assigned randomly to 1 of 4 treatments (saline solution, methylprednisolone, cefazolin sodium, methylprednisolone–cefazolin sodium) for 7 days. After the treatment period, sinus mucosa samples of the animals were examined stereologically. In addition, mucosa samples were used in the determination of myeloperoxidase (MPO) activity. Results: Methylprednisolone, cefazolin, and methylprednisolone-cefazolin had a positive effect on the reduction of neutrophil infiltration to the sinus mucosa in experimental bacterial rhinosinusitis as compared to the group treated with saline solution. However, the effects of methylprednisolone, cefazolin, and methylprednisolone-cefazolin did not significantly differ (p > .05). Similarly, the use of methylprednisolone, cefazolin, and methylprednisolone-cefazolin decreased MPO activity as compared to the group with saline solution (p < .05), and the difference among methylprednisolone, cefazolin, and methylprednisolone-cefazolin was statistically significant (p < .05). The most significant decrease in MPO (neutrophil marker enzyme) activity was determined in the animals treated with methylprednisolone-cefazolin (p < .05). Conclusions: Administering corticosteroids as an adjunct to antibiotics may accelerate the healing process in experimentally induced rhinosinusitis. In this model of rhinosinusitis, an MPO assay was supportive of this hypothesis, although stereological examination showed no statistically significant difference.
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Abstract
This study tests the hypothesis that montelukast sodium, a selective leukotriene receptor antagonist, will decrease the duration of the effusion of otitis media. Tympanometry and spectral gradient acoustic reflectometry were used to confirm the effusion of otitis media in patients between 2 and 12 years of age. Patients were treated with amoxicillin for 10 days and montelukast sodium or placebo for 30 days in a random, double-blind manner. Sixty patients completed the study: 31 received placebo and 29 received montelukast sodium. At a 4-week follow-up visit, 5 ears (16%) were free of effusion in the placebo group and 17 (58%) in the montelukast sodium group. The difference was significant. The efficacy of montelukast sodium in clearing the effusion was 49%.
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Affiliation(s)
- Jerome T Combs
- Department of Pediatrics, University of Connecticut School of Medicine, Meriden, CT 06450, USA
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Jung TTK, Park SK, Rhee CK. Effect of inhibitors of leukotriene and/or platelet activating factor on killed H. influenzae induced experimental otitis media with effusion. Int J Pediatr Otorhinolaryngol 2004; 68:57-63. [PMID: 14687688 DOI: 10.1016/j.ijporl.2003.09.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Our previous studies have shown that leukotriene (LT) and platelet activating factor (PAF) are important inflammatory mediators (IMs) in the pathogenesis of otitis media with effusion (OME). The purpose of this study was to determine the effect of a LT-inhibitor and/or PAF-antagonist on experimentally induced OME by killed H. influenzae in chinchillas. LT-inhibitor SCH-37224 and/or PAF-antagonist WEB-2170 were systematically administered, each separately or in combination, 2h prior and then at regular intervals after the injection of killed H. influenzae into the superior bullae. After 48h, OME was completely prevented in the combination group while it was only partially prevented in the other two separately treated groups. Animals in the control group all developed OME. Findings of this study suggest the importance of LT and PAF in the pathogenesis of OME and the usefulness of their blockers in the prevention of OME suggesting possible future therapeutic implication.
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Affiliation(s)
- Timothy T K Jung
- Division of Otolaryngology Head and Neck Surgery, Jerry L. Pettis Memorial Veterans Medical Center, Loma Linda University School of Medicine, Loma Linda, CA 92354, USA.
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Alper CM, Andalibi A, Bakaletz LO, Buchman C, Cayé-Thomasen P, Hellstrom SOM, Herman P, Hermansson A, Hussl B, Iino Y, Kawauchi H, Paparella MM, Sando I, Swarts JD, Takasaka T. Recent advances in otitis media. 4. Anatomy, cell biology, pathology, and animal models. Ann Otol Rhinol Laryngol 2002; 188:36-51. [PMID: 11968860 DOI: 10.1177/00034894021110s307] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Jeon EJ, Park YS, Choi YC, Yeo SW, Jung TT. Effect of inhibitor of tumor necrosis factor-alpha on experimental otitis media with effusion. Ann Otol Rhinol Laryngol 2001; 110:917-21. [PMID: 11642423 DOI: 10.1177/000348940111001005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Tumor necrosis factor (TNF)-alpha is important in the pathogenesis of otitis media with effusion (OME). The purpose of this study was to determine the effect of TNF-alpha antagonist on the outcome of lipopolysaccharide (LPS)-induced OME in rats. Otitis media was induced by injecting Pseudomonas aeruginosa LPS transtympanically. Another (combination) group was pretreated with TNF-alpha antagonist, soluble TNF receptor type I (sTNF RI), before transtympanic injection of LPS. Saline and phosphate-buffered saline solutions were used as controls. Twelve hours after the transtympanic injection, otoscopic examination and aspiration of middle ear effusion (MEE) were done. The temporal bones in each group were examined histopathologically, and the vascular permeability of the middle ear mucosa was measured by the Evans blue vital dye technique. In the LPS and combination groups, MEE developed in 90% and 0% of ears, respectively. The combination group showed less inflammation, less mucosal thickening, and significantly decreased vascular permeability as compared to the LPS group. Transtympanic administration of sTNF RI appears to suppress the development of LPS-induced OME. This study suggests that TNF-alpha antagonist, along with antibiotics, may have an adjunctive role in the future treatment of MEE.
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Affiliation(s)
- E J Jeon
- Department of Otolaryngology-Head and Neck Surgery, College of Medicine, The Catholic University of Korea, Seoul
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Agha AM, Mansour M. Effects of captopril on interleukin-6, leukotriene B(4), and oxidative stress markers in serum and inflammatory exudate of arthritic rats: evidence of antiinflammatory activity. Toxicol Appl Pharmacol 2000; 168:123-30. [PMID: 11032767 DOI: 10.1006/taap.2000.8985] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We previously demonstrated that captopril (CP) exhibited a high ability to inhibit enzymatically generated leukotrienes, particularly LTB(4), from stimulated intact human neutrophils. This finding together with the immunosuppressive effect of CP have proposed a possible antiinflammatory activity for the drug. Thus, the present study was conducted to investigate the effect of CP on immunologically mediated chronic inflammation; two models were chosen, namely, Freund's adjuvant arthritis and mixed-type hypersensitivity in rat. The effect of CP was assessed on the basis of physical parameter (paw edema) and biochemical markers in blood and inflammatory exudate. CP was given daily during the course of inflammation development. It was administered ip at three doses, viz. 1, 10, and 100 mg/kg. The results claimed that CP succeeded in suppressing edema evolution in hind paws of Freund's arthritic animals, during all phases of the disease. During the chronic phase of inflammation, in either model, CP reduced the elevated serum and exudate (local) LTB(4) and IL-6 levels. The effect on LTB(4) was more pronounced in the exudate and tended to be dose-related. The antiarthritic effect of CP was also accompanied by augmentation of serum level of protein thiols, with reduction or normalization of elevated systemic and/or local levels of lipid peroxide, superoxide dismutase, and glutathione. It could be concluded that long-term treatment with CP confers a good antiinflammatory activity against arthritis in rat, leading to improvement of the oxidative stress induced by the arthritic insult. The reparative effect of the drug could be mediated via reduction of LTB(4) and IL-6.
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Affiliation(s)
- A M Agha
- Pharmacology Department, Faculty of Pharmacy, Cairo University, Kasr El-Aini Street, Cairo, 11562, Egypt
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Karasen RM, Sutbeyaz Y, Aktan B, Ozdemir H, Gundogdu C. Effect of WEB 2170 BS, platelet activating factor receptor inhibitor, in the guinea pig model of middle ear inflammation. Ann Otol Rhinol Laryngol 2000; 109:549-53. [PMID: 10855565 DOI: 10.1177/000348940010900604] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Platelet activating factor (PAF), a potent inflammatory mediator, is a biologically active phospholipid. Recent studies have shown that PAF may play an important role in the pathogenesis of otitis media (OM). WEB 2170 BS has been shown to be a PAF antagonist both in vitro and in vivo. In this study, the anti-inflammatory effects of WEB 2170 BS were investigated in a guinea pig model of OM induced by middle ear (ME) inoculation of killed Staphylococcus aureus. The outcome of treatment was determined by measurement of myeloperoxidase activity in the samples of ME mucosa, evaluation of temporal bone histopathology, and the presence of ME fluid. The myeloperoxidase activity in the WEB 2170 BS-treated group was found to be significantly lower than that in the control group. Histopathology of the temporal bones indicated decreased inflammation in the treated group as compared to the controls. In addition, ME fluid was absent in 16 of the 20 ears of the 10 treated animals. These results demonstrate that WEB 2170 BS can produce significant anti-inflammatory effects in this model of OM.
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Affiliation(s)
- R M Karasen
- Department of Otolaryngology, School of Medicine, Ataturk University, Erzurum, Turkey
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Boie Y, Stocco R, Sawyer N, Greig GM, Kargman S, Slipetz DM, O'Neill GP, Shimizu T, Yokomizo T, Metters KM, Abramovitz M. Characterization of the cloned guinea pig leukotriene B4 receptor: comparison to its human orthologue. Eur J Pharmacol 1999; 380:203-13. [PMID: 10513580 DOI: 10.1016/s0014-2999(99)00514-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A cDNA clone coding for the guinea pig leukotriene B4 (BLT) receptor has been isolated from a lung cDNA library. The guinea pig BLT receptor has an open reading frame corresponding to 348 amino acids and shares 73% and 70% identity with human and mouse BLT receptors, respectively. Scatchard analysis of membranes prepared from guinea pig and human BLT receptor-transfected human embryonic kidney (HEK) 293 EBNA (Epstein-Bar Virus Nuclear Antigen) cells showed that both receptors displayed high affinity for leukotriene B4 (Kd value of approximately 0.4 nM) and were expressed at high levels (Bmax values ranging from 9 to 12 pmol/mg protein). The rank order of potency for leukotrienes and related analogs in competition for [3H]leukotriene B4 specific binding at the recombinant guinea pig BLT receptor is leukotriene B4 > 20-OH-leukotriene B4 > 12(R)-HETE ((5Z,8Z,10E,12(R)14Z)-12-hydroxyeicosatetraen -1-oic acid) > 12(S)-HETE ((5Z,8Z,10E,12(S)14Z)-12-Hydroxyeicosatetraen -1-oic acid) > 20-COOH-leukotriene B4 > U75302 (6-(6-(3-hydroxy-1E,5Z-undecadienyl)-2-pyridinyl)-1,5-hexane diol) >> leukotriene C4 = leukotriene D4 = leukotriene E4. For the human receptor the rank order of 12(S)-HETE, 20-COOH-leukotriene B4 and U75302 was reversed. Xenopus melanophore and HEK aequorin-based reporter gene assays were used to demonstrate that the guinea pig and human BLT receptors can couple to both the cAMP inhibitory and intracellular Ca2+ mobilization signaling pathways. However, in the case of the aequorin-expressing HEK cells (designated AEQ17-293) transfected with either the guinea pig or human BLT receptor, expression of Galpha16 was required to achieve a robust Ca2+ driven response. Leukotriene B4 was a potent agonist in functional assays of both the guinea pig and human BLT receptors. U-75302 a leukotriene B4 analogue which possesses both agonistic and antagonistic properties behaved as a full agonist of the guinea pig and human BLT receptors in AEQ17-293 cells and not as an antagonist. The recombinant guinea pig BLT receptor will permit the comparison of the intrinsic potencies of leukotriene B4 receptor antagonists used in guinea pig in vivo models of allergic and inflammatory disorders.
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Affiliation(s)
- Y Boie
- Department of Biochemistry and Molecular Biology, Merck Frosst Center for Therapeutic Research, Pointe Claire-Dorval, Quebec, Canada
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Engels F, Nijkamp FP. Pharmacological inhibition of leukotriene actions. PHARMACY WORLD & SCIENCE : PWS 1998; 20:60-5. [PMID: 9584338 DOI: 10.1023/a:1008698027211] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Leukotrienes represent a group of lipid mediators that play a very important role in a wide variety of pathological conditions. The presence of leukotrienes in inflammatory sites has been extensively documented, and accordingly research efforts have been directed towards the development of drugs that interfere with the formation or effects of leukotrienes. Although clinical application of such drugs has been disappointing in the past, recent discoveries of more potent and selective drugs seem to be promising. This review attempts to highlight some of these exciting developments.
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Affiliation(s)
- F Engels
- Department of Pharmacology & Pathophysiology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, The Netherlands
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Abstract
Despite multiple studies, the role of anti-inflammatory drugs in the treatment of AOM and OME is unclear. Although the AHCPR was against the use of steroids in OME, other studies suggest a possible role with potential cost savings and a decrease in the need for surgery in some patients. But the risk-benefit ratio of steroid treatment is unclear. There is some evidence that NSAIDs may decrease otalgia associated with AOM, but no proof that NSAIDs reduce or prevent inflammatory changes in the middle ear associated with AOM and OME.
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Affiliation(s)
- J E Fergie
- Driscoll Children's Hospital, Corpus Christi, Texas, USA
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Abstract
Leukotriene B4 is a pro-inflammatory mediator synthesised in myeloid cells from arachidonic acid. Synthesis is catalysed by 5-lipoxygenase and leukotriene A4 hydrolase and is increased by inflammatory mediators including endotoxin, complement fragments, tumor necrosis factor and interleukins. A nuclear membrane protein, 5-lipoxygenase activating protein, is an essential co-factor for 5-lipoxygenase. Leukotriene B4 induces recruitment and activation of neutrophils, monocytes and eosinophils. It also stimulates the production of a number of proinflammatory cytokines and mediators indicating an ability to augment and prolong tissue inflammation. Elevated levels of leukotriene B4 have been found in a number of inflammatory diseases and levels are related to disease activity in some of these. Initial data from pharmacological inhibition studies support a role for leukotriene B4 in the pathogenesis of neutrophil mediated tissue damage, and treatments which reduce its production or block its effects may prove beneficial in neutrophil mediated inflammatory diseases.
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Affiliation(s)
- S W Crooks
- Department of Medicine, Queen Elizabeth Hospital, Edgbastón, Birmingham, UK.
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