scholarly journals Cyclo-oxygenase-2 contributes to constitutive prostanoid production in rat kidney and brain

2005 ◽  
Vol 391 (3) ◽  
pp. 561-566 ◽  
Author(s):  
Pierre-Olivier Hétu ◽  
Denis Riendeau
Keyword(s):  
Rat Kidney ◽  
Significant Inhibition ◽  
Complete Analysis ◽  
Inflammatory Conditions ◽  
Prostanoid Production ◽  
Cox 2 ◽  
The Individual ◽  
Cox 2 Inhibitors ◽  
Cox 1 ◽  
Prostanoid Synthesis

Cyclo-oxygenases (COXs) catalyse the synthesis of PGH2 (prostaglandin H2), which serves as the common substrate for the production of PGE2, PGD2, PGF2α, prostacyclin (or PGI2) and TXs (thromboxanes). While COX-1 is the major isoform responsible for prostanoid synthesis in healthy tissues, little information is available on the contribution of constitutive COX-2 to the various prostanoid synthetic pathways under non-inflammatory conditions. To evaluate further the role of COX-2 in prostanoid biosynthesis, rats were acutely treated with the selective COX-1 inhibitor SC-560 [5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-trifluoromethylpyrazole] or the selective COX-2 inhibitors MF tricyclic [3-(3,4-difluorophenyl)-4-(4-(methylsulphonyl)phenyl)-2-(5H)-furanone] and DFU [5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulphonyl)phenyl-2-(5H)-furanone]. Selected tissues were then processed for a complete analysis of their prostanoid content by liquid chromatography MS. Whereas the treatment with SC-560 caused a 60–70% inhibition in the total prostanoid content of most tissues examined, a significant decrease (35–50%) in total prostanoid content following selective COX-2 inhibition was solely detected for kidney and brain tissues. Analysis of the individual prostanoids reveals significant inhibition of 6-oxo-PGF1α, PGE2, PGD2, PGF2α and TXB2 in the kidney and inhibition of all these prostanoids with the exception of PGD2 in the forebrain. These results demonstrate that constitutively expressed COX-2 contributes to the production of prostanoids in kidney and brain for each of the PGE2, PGI2 and TXB2 pathways under non-inflammatory conditions. Approaches to modulate inflammation through specific inhibition of terminal synthases, such as mPGES-1 (microsomal PGE2 synthase-1), thus have the potential to differ from COX-2 inhibitors and non-selective non-steroidal anti-inflammatory drugs with regard to effects on constitutive prostanoid synthesis and on renal function.

scholarly journals Evolution of Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): Cyclooxygenase (COX) Inhibition and Beyond

2008 ◽  
Vol 11 (2) ◽  
pp. 81 ◽  
Author(s):  
Praveen Rao ◽  
Edward E. Knaus
Keyword(s):  
Mechanism Of Action ◽  
Cardiovascular Effects ◽  
Nitric Oxide Donor ◽  
Structural Basis ◽  
Magic Bullet ◽  
Inflammatory Conditions ◽  
Cox 2 ◽  
Anti Inflammatory ◽  
Cox 2 Inhibitors ◽  
Cox 1

Purpose. NSAIDs constitute an important class of drugs with therapeutic applications that have spanned several centuries. Treatment of inflammatory conditions such as rheumatoid arthritis (RA) and osteoarthritis (OA) starting from the classic drug aspirin to the recent rise and fall of selective COX-2 inhibitors has provided an enthralling evolution. Efforts to discover an ultimate magic bullet to treat inflammation continues to be an important drug design challenge. This review traces the origins of NSAIDs, their mechanism of action at the molecular level such as cyclooxygenase (COX) inhibition, development of selective COX-2 inhibitors, their adverse cardiovascular effects, and some recent developments targeted to the design of effective anti-inflammatory agents with reduced side effects. Methods. Literature data is presented describing important discoveries pertaining to the sequential development of classical NSAIDs and then selective COX-2 inhibitors, their mechanism of action, the structural basis for COX inhibition, and recent discoveries. Results. A brief history of the development of NSAIDs and the market withdrawal of selective COX-2 inhibitors is explained, followed by the description of prostaglandin biosynthesis, COX isoforms, structure and function. The structural basis for COX-1 and COX-2 inhibition is described along with methods used to evaluate COX-1/COX-2 inhibition. This is followed by a section that encompasses the major chemical classes of selective COX-2 inhibitors. The final section describes briefly some of the recent advances toward developing effective anti-inflammatory agents such as nitric oxide donor NO-NSAIDs, dual COX/LOX inhibitors and anti-TNF therapy. Conclusions. A great deal of progress has been made toward developing novel anti-inflammatory agents. In spite of the tremendous advances in the last decade, the design and development of a safe, effective and economical therapy for treating inflammatory conditions still presents a major challenge.

Effects of cyclooxygenase inhibition on canine coronary artery blood flow and thrombosis

2008 ◽  
Vol 294 (1) ◽  
pp. H145-H155 ◽  
Author(s):  
Ting-Ting Hong ◽  
Jinbao Huang ◽  
Terrance D. Barrett ◽  
Benedict R. Lucchesi
Keyword(s):  
Coronary Artery ◽  
Vascular Reactivity ◽  
Thrombus Formation ◽  
Normal Coronary Artery ◽  
Cox Inhibitors ◽  
Inflammatory Conditions ◽  
Cox Inhibitor ◽  
Cox 2 ◽  
Cox 2 Inhibitors ◽  
Cox 1

This study was designed to determine the effect of inhibitors of cyclooxygenase (COX)-1, COX-2, and the nonselective COX inhibitor naproxen on coronary vasoactivity and thrombogenicity under baseline and lipopolysaccharide (LPS)-induced inflammatory conditions. We hypothesize that endothelial COX-1 is the primary COX isoform in the canine normal coronary artery, which mediates arachidonic acid (AA)-induced vasodilatation. However, COX-2 can be induced and overexpressed by inflammatory mediators and becomes the major local COX isoform responsible for the production of antithrombotic prostaglandins during systemic inflammation. The interventions included the selective COX-1 inhibitor SC-560 (0.3 mg/kg iv), the selective COX-2 inhibitor nimesulide (5 mg/kg iv), or the nonselective COX inhibitor naproxen (3 mg/kg iv). The selective prostacyclin (IP) receptor antagonist RO-3244794 (RO) was used as an investigational tool to delineate the role of prostacyclin (PGI2) in modulating vascular reactivity. AA-induced vasodilatation of the left circumflex coronary artery was suppressed to a similar extent by each of the COX inhibitors and RO. The data suggest that AA-induced vasodilatation in the normal coronary artery is mediated by a single COX isoform, the constitutive endothelial COX-1, which is reported to be susceptible to COX-2 inhibitors. The effect of the COX inhibitors on thrombus formation was evaluated in a model of carotid artery thrombosis secondary to electrolytic-induced vessel wall injury. Pretreatment with LPS (0.5 mg/kg iv) induced a systemic inflammatory response and prolonged the time-to-occlusive thrombus formation, which was reduced in the LPS-treated animals by the administration of nimesulide. In contrast, neither SC-560 nor naproxen influenced the time to thrombosis in the animals pretreated with LPS. The data are of significance in view of reported adverse cardiovascular events observed in clinical trials involving the use of selective COX-2 inhibitors, thereby suggesting that the endothelial constitutive COX-1 and the inducible vascular COX-2 serve important functions in maintaining vascular homeostasis.

Cyclooxygenase-2 plays a significant role in regulating the tone of the fetal lamb ductus arteriosus

1999 ◽  
Vol 276 (3) ◽  
pp. R913-R921 ◽  
Author(s):  
Ronald I. Clyman ◽  
Pierre Hardy ◽  
Nahid Waleh ◽  
Yao Qi Chen ◽  
Françoise Mauray ◽  
...  
Keyword(s):  
Significant Role ◽  
Ductus Arteriosus ◽  
Late Gestation ◽  
Relative Contribution ◽  
Cox Inhibitor ◽  
Fetal Lamb ◽  
Cox 2 ◽  
Cox 2 Inhibitors ◽  
Cox 1

Nonselective cyclooxygenase (COX) inhibitors are potent tocolytic agents but have adverse effects on the fetal ductus arteriosus. We hypothesized that COX-2 inhibitors may not affect the ductus if the predominant COX isoform is COX-1. To examine this hypothesis, we used ductus arteriosus obtained from late-gestation fetal lambs. In contrast to our hypothesis, fetal lamb ductus arteriosus expressed both COX-1- and COX-2-immunoreactive protein (by Western analysis). Although COX-1 was found in both endothelial and smooth muscle cells, COX-2 was found only in the endothelial cells lining the ductus lumen (by immunohistochemistry). The relative contribution of COX-1 and COX-2 to PGE2 synthesis was consistent with the immunohistochemical results: in the intact ductus, PGE2 formation was catalyzed by both COX-1 and COX-2 in equivalent proportions; in the endothelium-denuded ductus, COX-2 no longer played a significant role in PGE2 synthesis. NS-398, a selective inhibitor of COX-2, was 66% as effective as the selective COX-1 inhibitor valeryl salicylate and the nonselective COX inhibitor indomethacin in causing contraction of the ductus in vitro. At this time, caution should be used when recommending COX-2 inhibitors for use in pregnant women.

Involvement of cyclooxygenase 2 (COX-2) in intrinsic tone of isolated guinea pig

1995 ◽  
Vol 73 (11) ◽  
pp. 1561-1567 ◽  
Author(s):  
L. Charette ◽  
C. Misquitta ◽  
J. Guay ◽  
D. Riendeau ◽  
T. R. Jones
Keyword(s):  
Guinea Pig ◽  
Time Course ◽  
Cyclooxygenase 2 ◽  
Maximal Response ◽  
Pharmacological Agents ◽  
Cyclooxygenase 1 ◽  
Inflammatory Drugs ◽  
Cox 2 ◽  
Cox 2 Inhibitors ◽  
Cox 1

Indomethacin and related nonsteroidal anti-inflammatory drugs relax prostanoid-dependent intrinsic tone of isolated guinea pig trachea by inhibiting cyclooxygenase (COX). Recently, a second isoform of COX (COX-2) was discovered, which differed from COX-1 with respect to protein structure, transcriptional regulation, and susceptibility to inhibition by pharmacological agents. It is now known that indomethacin nonselectively inhibits COX-1 and COX-2, whereas NS-398 is a selective inhibitor of COX-2. In the present study we compared the activity of a selective (NS-398) and nonselective (indomethacin) COX-2 inhibitor on intrinsic tone of isolated guinea pig trachea. NS-398 ≥ indomethacin produced a reversal of intrinsic tone with a similar concentration-dependent (10 nM to 1 μM) time course (Tmax approximately 20–45 min), potency (EC50 1.7 and 5.6 nM, respectively), and maximal response. Contractions to cholinergic nerve stimulation (45 V, 0.5 ms, 0.1–32 Hz) and histamine were similarly modulated in tissues relaxed with the selective or nonselective COX-2 inhibitors. Immunoblot analyses showed that COX-2 protein synthesis was induced in both the cartilage and smooth muscle portions of the trachea during changes in intrinsic tone. These findings are consistent with pharmacological results and provide the first demonstration that prostanoid tone in isolated guinea pig trachea is dependent on COX-2 activity. The results also suggest that the activity of indomethacin in this preparation is likely related to COX-2 inhibition.Key words: cyclooxygenase 2, relaxation, guinea pig trachea, cyclooxygenase 1.

New indomethacin analogs as selective COX‐2 inhibitors: Synthesis, COX‐1/2 inhibitory activity, anti‐inflammatory, ulcerogenicity, histopathological, and docking studies

2020 ◽  
Author(s):  
Khaled R. A. Abdellatif ◽  
Eman K. A. Abdelall ◽  
Heba A. H. Elshemy ◽  
El‐Shaymaa El‐Nahass ◽  
Maha M. Abdel‐Fattah ◽  
...  
Keyword(s):  
Inhibitory Activity ◽  
Docking Studies ◽  
Cox 2 ◽  
Anti Inflammatory ◽  
Cox 2 Inhibitors ◽  
Cox 1

scholarly journals COX-1 and COX-2 Contributions to Basal and IL-1β-Stimulated Prostanoid Synthesis in Human Neonatal Cerebral Microvascular Endothelial Cells

2002 ◽  
Vol 52 (3) ◽  
pp. 342-348 ◽  
Author(s):  
Helena Parfenova ◽  
Vladimir Levine ◽  
Wendy M Gunther ◽  
Massroor Pourcyrous ◽  
Charles W Leffler
Keyword(s):  
Endothelial Cells ◽  
Microvascular Endothelial Cells ◽  
Cox 2 ◽  
Microvascular Endothelial ◽  
Cox 1 ◽  
Prostanoid Synthesis

scholarly journals Chlorinated cobalt alkyne complexes derived from acetylsalicylic acid as new specific antitumor agents

2018 ◽  
Vol 47 (12) ◽  
pp. 4341-4351 ◽  
Author(s):  
Victoria Obermoser ◽  
Daniel Baecker ◽  
Carina Schuster ◽  
Valentin Braun ◽  
Brigitte Kircher ◽  
...  
Keyword(s):  
Antitumor Agents ◽  
Tumor Cell Lines ◽  
Growth Inhibitory ◽  
Cox 2 ◽  
Alkyne Complexes ◽  
Inhibitory Potential ◽  
Cox 2 Inhibitors ◽  
Ht 29 ◽  
Cox 1 ◽  
Mcf 7

Chlorine-substituted [(prop-2-ynyl)-2-acetoxybenzoate]dicobalthexacarbonyl complexes are selective COX-2 inhibitors with growth-inhibitory potential against COX-1/2 containing MDA-MB-231 and HT-29 tumor cell lines. The metabolic activity of non-tumorigenic HS-5 cells and COX-1/2-independent MCF-7 cells is not influenced.

scholarly journals Synthesis of Novel Benzodifuranyl; 1,3,5-Triazines; 1,3,5-Oxadiazepines; and Thiazolopyrimidines Derived from Visnaginone and Khellinone as Anti-Inflammatory and Analgesic Agents

Molecules ◽  
2020 ◽  
Vol 25 (1) ◽  
pp. 220 ◽  
Author(s):  
Ameen Ali Abu-Hashem ◽  
Sami A Al-Hussain ◽  
Magdi E. A. Zaki
Keyword(s):  
Sodium Ethoxide ◽  
Standard Drug ◽  
Chemical Structures ◽  
Cyclooxygenase 1 ◽  
Analgesic Agents ◽  
Cox 2 ◽  
Anti Inflammatory ◽  
New Compounds ◽  
Cox 2 Inhibitors ◽  
Cox 1

Novel (4-methoxy or 4,8-dimethoxy)-3-methyl-N-(6-oxo-2-thioxo-1,2,3, 6-tetrahydro- pyrimidin-4-yl) benzo [1,2-b: 5, 4-b’] difuran-2-carboxamide (5a–b) has been synthesized by the reaction of visnagenone–ethylacetate (2a) or khellinone–ethylacetate (2b) with 6-aminothiouracil in dimethylformamide or refluxing of benzofuran-oxy-N-(2-thioxopyrimidine) acetamide (4a–b) in sodium ethoxide to give the same products (5a,b) in good yields. Thus, compounds 5a–b are used as an initiative to prepare many new heterocyclic compounds such as 2-(4-(3-methylbenzodifuran- 2-carbox-amido) pyrimidine) acetic acid (6a–b), N-(thiazolo[3, 2-a]pyrimidine)-3-methylbenzo- difuran-2-carboxamide (7a–b), N-(2-thioxopyrimidine)-methylbenzodifuran-2-carbimidoylchloride (8a–b), N-(2-(methyl-thio) pyrimidine)-3-methylbenzodifuran-2-carbimidoylchloride (9a–b), N-(2, 6 -di(piperazine or morpholine)pyrimidine)-1-(3-methylbenzodifuran)-1-(piperazine or morpholine) methanimine(10a–d), 8-(methylbenzodifuran)-thiazolopyrimido[1,6-a][1,3,5]triazine-3,5-dione (11a –b), 8-(3-methyl benzodifuran)-thiazolopyrimido[6,1-d][1,3,5]oxadiazepine-trione (12a–b), and 2,10 -di(sub-benzylidene)-8-(3-methylbenzodifuran)-thiazolopyrimido[6,1-d][1,3,5]oxadiazepine-3,5,11- trione (13a–f). All new chemical structures were illustrated on the basis of elemental and spectral analysis (IR, NMR, and MS). The new compounds were screened as cyclooxygenase-1/ cyclooxygenase-2 (COX-1/COX-2) inhibitors and had analgesic and anti-inflammatory activities. The compounds 10a–d and 13a–f had the highest inhibitory activity on COX-2 selectivity, with indices of 99–90, analgesic activity of 51–42% protection, and anti-inflammatory activity of 68%–59%. The inhibition of edema for the same compounds, 10a–d and 13a–f, was compared with sodium diclofenac as a standard drug.

Aggravation by Selective COX-1 and COX-2 Inhibitors of Dextran Sulfate Sodium (DSS)-Induced Colon Lesions in Rats

2007 ◽  
Vol 52 (9) ◽  
pp. 2095-2103 ◽  
Author(s):  
Mitsuaki Okayama ◽  
Shusaku Hayashi ◽  
Yoko Aoi ◽  
Hikaru Nishio ◽  
Shinichi Kato ◽  
...  
Keyword(s):  
Dextran Sulfate ◽  
Dextran Sulfate Sodium ◽  
Cox 2 ◽  
Cox 2 Inhibitors ◽  
Cox 1
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