Search results for "endoperoxide"
showing 10 items of 65 documents
The pyrrole moiety as a template for COX-1/COX-2 inhibitors
2000
Aroyl- and thiophene-substituted pyrrole derivatives have been synthesized as a new class of COX-1/COX-2 inhibitors. The inhibition of COX-1 was evaluated in a biological system using bovine PMNLs as the enzyme source, whereas LPS-stimulated human monocytes served as the enzyme source for inducible COX-2. The determination of the concentration of arachidonic acid metabolites was performed by HPLC for COX-1 and RIA for COX-2. Variation of the substitution pattern led to a series of active compounds which showed inhibition for COX-1 and COX-2. Structural requirements for the development of COX-1/COX-2 inhibitors are discussed.
Preemptive analgesia-related gene and protein expression in third molar surgeries under non steroidal anti-inflammatory drug protocols : A PROSPERO-r…
2018
Background This study aimed to review translational studies focusing on third molar removal surgeries through a systematic analytical approach. Material and Methods A PROSPERO-registered systematic review (CRD42017060455) was conducted following the PRISMA statement to summarize current knowledge on gene expression in third molar surgeries. A search was performed in PubMed’s Medline and Scopus databases, without date or language restrictions, using the logical expression {[(Third molar) OR (preemptive) OR (cyclooxygenase inhibitors) OR (acute inflammation) AND (gene expression)]}. Results All studies included in the analysis evaluated gene expression in a third molar extraction model, using…
Adjuncts for ovarian stimulation: when do we adopt “orphan indications” for approved drugs?
2009
Several drugs, shown to be safe for other uses, have proven to be highly effective adjuncts for ovarian stimulation. The authors evaluate these "orphan" indications and make recommendations so that more patients will benefit from their use.
Therapeutic administration of 3,4,5-trimethoxy-4'-fluorochalcone, a selective inhibitor of iNOS expression, attenuates the development of adjuvant-in…
2003
We have previously investigated the effects of a series of dimethoxy- and trimethoxychalcone derivatives, with various patterns of fluorination, on nitric oxide production in LPS-stimulated murine RAW 264.7. The present study was designed to determine if 3,4,5-trimethoxy-4'-fluorochalcone (CH 17) could modulate the production of NO and/or prostaglandins in vivo. On the mouse macrophage cell line RAW 264.7 CH 17 inhibited dose-dependently NO production, with an IC(50) value in the nanomolar range, and reduced PGE(2) levels by a 58% at 10 microM. This compound had no direct inhibitory effect on iNOS and COX-2 activities. NO reduction was the consequence of inhibition of the expression of iNOS…
Incorporation and metabolism of trans 20∶5 in endothelial cells. Effect on prostacyclin synthesis
2000
To study the ability of long-chain trans fatty acids (FA) to be incorporated and metabolized into endothelial cells, bovine aortic endothelial cells were incubated with medium enriched eicosapentaenoic acid (EPA) bound to albumin (M2) or one of its geometrical isomers: 20:5 5c,8c,11t,14c,17c (M3), 20:5 5c,8c,11c,14c,17t (M4), or 20:5 5c,8c,11t,14c,17t (M5). After 48 h of incubation, supernatant and cells were harvested and their lipids were analyzed, including prostacyclin synthesis. EPA and 22:5n-3 of endothelial cells incubated with M2 were, respectively, three and two times higher than in control cells (incubated in M1, without any fatty acid added), whereas 22:6n-3 increased only in the…
Immunohistochemical localization of cyclooxygenase isoforms in the organ of Corti and the spiral ganglion cells of guinea pig cochlea.
2003
Prostaglandins have been used in experimental models and clinical studies for the therapy of sudden hearing loss and tinnitus with conflicting results. However, little is known about the rate-limiting enzymes of prostaglandin synthesis in the inner ear, the generally constitutively expressed cyclooxygenase 1 (COX-1) and the distress-inducible cycloxygenase 2 (COX-2). To extend our knowledge concerning the physiological expression and localization of these two enzymes, immunohistochemical stainings of the guinea pig cochlea were performed. Light microscopical analysis revealed a homogenous distribution of COX-1 within nearly all cell types of the organ of Corti, but no COX-1 expression in th…
Leptin: A pivotal mediator of intestinal inflammation in mice
2002
Abstract Background & Aims: In addition to acting as a regulator of food intake and energy expenditure, leptin can also modulate immune and inflammatory responses. The role of leptin in intestinal inflammation is the focus of the present study. Methods: Acute and chronic colitis were induced in leptin-deficient ob/ob or wild-type (WT) mice using dextran sulfate sodium (DSS) or trinitrobenzene sulfonic acid (TNBS). The severity of colitis was evaluated, and possible mechanisms were studied. Results: Leptin directly stimulates intraepithelial lymphocytes (IELs) and lamina propria mononuclear cells (LPMCs). In the DSS acute model, ob/ob mice exhibited a 72% reduction of colitis severity and sp…
Cytotoxicity of Endoperoxides from the Caribbean Sponge Plakortis halichondrioides towards Sensitive and Multidrug-Resistant Leukemia Cells: Acids vs…
2016
The 6-epimer of the plakortide H acid (1), along with the endoperoxides plakortide E (2), plakortin (3), and dihydroplakortin (4) have been isolated from a sample of the Caribbean sponge Plakortis halichondrioides. To perform a comparative study on the cytotoxicity towards the drug-sensitive leukemia CCRF-CEM cell line and its multi-drug resistant subline CEM/ADR5000, the acid of plakortin, namely plakortic acid (5), as well as the esters plakortide E methyl ester (6) and 6-epi-plakortide H (7) were synthesized by hydrolysis and Steglich esterification, respectively. The data obtained showed that the acids (1, 2, 5) exhibited potent cytotoxicity towards both cell lines, whereas the esters s…
Effects of some isoxazolpyrimidine derivatives on nitric oxide and eicosanoid biosynthesis
2000
Abstract The inhibitory effect of some isoxazolpyrimidine derivatives on iNOS and COX-2 endotoxin induction in mouse peritoneal macrophages has been studied. Three of these compounds inhibited nitrite and PGE2 accumulation in a concentration dependent-manner at μM range. None of these active compounds affected iNOS, COX-2, COX-1 or PLA2 activities, although some reduced iNOS or COX-2 expression. Besides, no effect was observed on human neutrophil inflammatory responses (LTB4 biosynthesis and Superoxide or elastase release). Active compounds were assayed by oral administration in the mouse air pouch model, where they inhibited nitrite accumulation without affecting PGE 2 levels or leukocyte …
Endogenous nitric oxide inhibits leukotriene B4 release from rat alveolar macrophages
1997
Effects of endogenous nitric oxide (NO) on the release of mediators of the lipoxygenase and cyclo-oxygenase pathway from rat alveolar macrophages were studied. Alveolar macrophages, freshly isolated or after 18-h culture, were incubated in (amino acid-free) Krebs medium and labelled with [3H]arachidonic acid. The release of [3H]leukotriene B4 and [3H]prostanoids (separated by high performance liquid chromatography) was determined. A 23187 was used as stimulus, as rising intracellular Ca2+ activates directly the phospholipase A2 and lipoxygenase pathway. A 23187 (10 microM) enhanced [3H]leukotriene B4 release from freshly prepared alveolar macrophages about 65-fold, but only 5- to 6-fold fro…