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Pope Edward C - - 2002
Eicosanoids are a group of oxygenated fatty-acid derivatives formed from C20 polyunsaturated fatty acids including arachidonic and eicosapentaenoic acids. In mammals, these compounds have been shown to be key molecules in several physiological processes including regulation of the vascular system. This study determined whether eicosanoids or their precursors are involved ...
Quraishi Omar - - 2002
Prostaglandin E(2) synthase (PGE synthase) is one of the membrane-associated proteins in the eicosanoid and glutathione metabolism (MAPEG) family of microsomal enzymes and constitutes a novel inducible enzyme involved in inflammation and pyretic responses. We report, using a reversed-phase HPLC assay for the production of tritiated prostaglandin E(2) (PGE(2)) by ...
Aljamali Majd - - 2002
High concentrations of PGE(2) and PGF(2alpha) were identified by radio-immunoassay (RIA) and/or gas chromatography/mass spectrometry (GC/MS) in the hemolymph, salivary glands and saliva of the lone star tick Amblyomma americanum (L.). Binding studies indicated that PGE(2) was free and not bound to any proteins in the hemolymph. A small amount ...
Zelle-Rieser Claudia - - 2002
Monocyte-derived dendritic cells (moDCs) are increasingly used in clinical settings to stimulate tumor immunity. Prostaglandin E2 (PGE2), which is a member of the eicosanoid family of oxygenated arachidonic acid derivatives generated through the action of cyclooxygenases (COXs), is frequently used to enhance the tumor necrosis factor-alpha-induced terminal maturation of moDCs. ...
Kashiwagi Kenji - - 2002
The pharmacological differences between isopropyl unoprostone (referred to as unoprostone) and latanoprost, concerning their induction of endogenous prostaglandin E(2)(PGE(2)) and affinity to a human prostaglandin transporter (PGT), were investigated. Freshly dissected bovine iris tissues were incubated with major intraocular metabolites of unoprostone, M1 and M2, acid of latanoprost, or PGF(2 ...
B?umer Wolfgang - - 2002
Isolated perfused bovine uteri were used to study the irritation potential of antiseptics frequently used in veterinary practice for the treatment of endometritis. Comparable to the isolated perfused bovine udder (Kietzmann et al., 1993), the viability of uteri obtained directly after slaughtering of cows, was tested with the help of ...
Yamaguchi Yoshitaka - - 2002
20-Hydroxyeicosatetraenoic acid (20-HETE) has been shown to be an arachidonic acid metabolite of the cytochrome P450 (CYP) enzymes belonging to the CYP4A subfamily and is a predominant regulator of renal vascular tone and tubular ion reabsorption in rat kidney. CYP4A8 is one of the CYP4A enzymes expressed in rat kidney, ...
Hornych A - - 2002
Senescence is associated with a decreased activity of enzyme delta-6 desaturase, which converts linoleic acid to gamma-linolenic acid. This enzymatic defect may alter the composition of plasma and membrane lipids, and influences the biosynthesis of renal prostaglandins. Exogenous supplementation of GLA during 3 months increases the plasma level of dihomo-gamma-linolenic ...
Armstrong M B - - 2001
The discovery of homologs of the brown fat uncoupling protein(s) (UCP) UCP-2 and UCP-3 revived the hypothesis of uncoupling protein involvement in the regulation of energy metabolism. Thus we hypothesized that UCP-2 would be regulated in the hepatocyte by fatty acids, which are known to control other energy-related metabolic processes. ...
Imbs A B - - 2001
The influence of solar irradiance and seasons on prostaglandin (PG) and arachidonic acid (AA) content in the marine red alga Gracilaria verrucosa (Huds.) Papenf. (unattached form) was investigated. PGA(2), PGE(2), PGF(2), and 15-keto-PGE(2) were isolated from the alga, quantitatively analyzed as 4-methyl-7-methoxycoumarin esters by high-performance liquid chromatography, and their chemical ...
Soper D L - - 2001
A series of novel C(1) alkylphosphinic acid analogues of the prostaglandin-F family have been evaluated at the eight human prostaglandin receptors for potential use in the treatment of osteoporosis. Using molecular modeling as a tool for structure-based drug design, we have discovered that the phosphinic acid moiety (P(O)(OH)R) behaves as ...
Aitken A E - - 2001
Cytochrome P4504A4 (CYP4A4) is a hormonally induced pulmonary cytochrome P450 which metabolizes prostaglandins and arachidonic acid (AA) to their omega-hydroxylated products. Although the physiological function of this enzyme is unknown, prostaglandins play an important role in the regulation of reproductive, vascular, intestinal, and inflammatory systems and 20-hydroxyeicosatetraenoic acid, the omega-hydroxylated ...
Woo H G - - 2001
In order to delineate the mechanism involved in the anti-inflammatory activity of rutaecarpine, its effects on the production of prostaglandin (PG) and therein involved enzymes were examined. Rutaecarpine reduced the production of PGE(2) in RAW264.7 cells treated with lipopolysaccharide (LPS) in a dose dependent manner when added to the culture ...
Zakar T - - 2001
Prostaglandins are important regulators of many aspects of reproductive processes from ovulation, fertilization and pregnancy recognition to labor and parturition. These biologically potent compounds are members of the large family of eicosanoids, derived from polyunsaturated fatty acids, principally arachidonic acid, found in the membrane phospholipids of virtually every cell of ...
Urquhart P - - 2001
Human saphenous vein endothelial cells (HSVECs) derived from primary cultures of adult human veins constitute an excellent in vitro model for studying human endothelial metabolism. In this study we report the (14)C-labelled prostanoid profile of HSVECs under resting and stimulated conditions and the effect of the n-3 polyunsaturated fatty acids ...
Klein T - - 2001
Isoprostanes comprise a group of free radical-catalyzed products of arachidonic acid. However, there is recent evidence pointing towards an enzyme-dependent formation of isoprostanes. With the use of isolated rat glomeruli we addressed the mechanisms of isoprostane generation. Synthesis of prostanoids and isoprostanes, including 8-epi-PGF(2alpha), was studied under conditions favouring radical ...
Boutaud O - - 2001
These investigations characterize the covalent binding of reactive products of prostaglandin H-synthases (PGHSs) to the enzyme and to other molecules. The intermediate product of oxygenation of arachidonic acid by the PGHSs, prostaglandin (PG) H2, undergoes rearrangement to the highly reactive gamma-keto aldehydes, levuglandin (LG) E2 and D2. We previously have ...
Bäumer W - - 2001
Using the isolated perfused bovine udder as an in-vitro model of skin inflammation, the effects of topically administered arachidonic acid on prostaglandin and leukotriene synthesis have been shown previously. In this study, the effects of indometacin (indomethacin) and clobetasol-17-propionate (administered topically) as well as flunixin meglumine and meloxicam (administered via ...
Bylund J - - 2001
cDNA of a novel human cytochrome P450 was cloned from human liver by reverse transcription-polymerase chain reaction and designated CYP4F12. The open reading frame coded for 524 amino acids, and the sequence could be aligned with 78-83% amino acid identity to the four human CYP4F enzymes (CYP4F2, CYP4F3, CYP4F8 and ...
Saiga A - - 2001
We have previously shown the expression of group X secretory phospholipase A(2) (sPLA(2)-X) in mouse splenic macrophages and its powerful potency for releasing fatty acids from various intact cell membranes. Here, we examined the potency of sPLA(2)-X in the production of lipid mediators in murine peritoneal macrophages. Mouse sPLA(2)-X was ...
Akrishnan V R - - 2001
Biochemical assessment of liver damage during ethanol-induced stress was done by measuring the activities of serum enzymes, viz., aspartate transaminase (AST) and alkaline phosphatase (ALP), which were significantly elevated in rats fed ethanol. Ethanol administration for a period of 60 days modifies the fatty acid composition, and the analysis of ...
Olson D M - - 2001
OBJECTIVE: We determined the relative abundance of prostaglandin endoperoxide H synthase type 1 and type 2 messenger ribonucleic acid levels in the human fetus and newborn infant. STUDY DESIGN: We used ribonuclease protection assays and normalized values to messenger ribonucleic acid of cyclophilin. Tissues were obtained from all 3 trimesters ...
Thuresson E D - - 2001
Prostaglandin endoperoxide H synthases-1 and -2 (PGHSs) catalyze the committed step in prostaglandin biosynthesis. Both isozymes can oxygenate a variety of related polyunsaturated fatty acids. We report here the x-ray crystal structure of dihomo-gamma-linolenic acid (DHLA) in the cyclooxygenase site of PGHS-1 and the effects of active site substitutions on ...
Krieger N S - - 2000
Metabolic acidosis induces bone calcium efflux initially by physicochemical dissolution and subsequently by cell-mediated mechanisms involving inhibition of osteoblasts and stimulation of osteoclasts. In rat kidney, acidosis increases endogenous prostaglandin synthesis, and in bone, prostaglandins are important mediators of resorption. To test the hypothesis that acid-induced bone resorption is mediated ...
Koljak R - - 2001
In vertebrates, the synthesis of prostaglandin hormones is catalyzed by cyclooxygenase (COX)-1, a constitutively expressed enzyme with physiological functions, and COX-2, induced in inflammation and cancer. Prostaglandins have been detected in high concentrations in certain corals, and previous evidence suggested their biosynthesis through a lipoxygenase-allene oxide pathway. Here we describe ...
Kozak K R - - 2000
Cyclooxygenases (COX) play an important role in lipid signaling by oxygenating arachidonic acid to endoperoxide precursors of prostaglandins and thromboxane. Two cyclooxygenases exist which differ in tissue distribution and regulation but otherwise carry out identical chemical functions. The neutral arachidonate derivative, 2-arachidonylglycerol (2-AG), is one of two described endocannabinoids and ...
Nadin L - - 2000
The quantitative importance of prostaglandin H synthase (PGHS)-mediated cooxidation of all-trans-retinoic acid (ATRA) was evaluated in human liver microsomes (n=17) in relation to CYP-dependent ATRA 4-hydroxylation. Observed rates of ATRA cooxidation (4.6 - 20 pmol mg protein(-1) min(-1)) and 4-hydroxylation (8.7 - 45 pmol mg protein(-1) min(-1)) were quantitatively similar ...
Leis H J - - 2000
Prostaglandin E(2) production stimulated by various agents (arachidonic acid, prostaglandin F(2alpha), ionomycin, the calcium ionophore A23187, and melittin) was investigated after pretreatment of murine osteoblast-like MC3T3-E1 cells with the putative phospholipase C blocker, U73122. The aminosteroid dose dependently inhibited prostaglandin E(2) production induced by all agonists, except arachidonic acid. The ...
Bäumer W - - 2000
The aim of this study was to examine whether the isolated perfused bovine udder could be used as a suitable in vitro inflammation model. A common in vivo inflammation model is arachidonic acid-induced inflammation in mouse ears. As an in vitro substitute for this model, arachidonic acid was administered topically ...
Baie S H - - 2000
Channa striatus, a fresh water snakehead fish, is reported to enhance dermal wound healing. Biochemical components such as amino acids and fatty acids are important for the synthesis of collagen fibers during wound healing. Arachidonic acid, a precursor of prostaglandin plays a vital role in healing the wounds. Haruan (C. ...
Gostner A - - 2000
The short-chain fatty acid butyrate is regarded as a regulative agent in haemostasis of mucosal cell turnover. Inhibition of prostaglandin E2 synthesis is particularly involved in this regulation process. In the present study, proliferation was stimulated in colonic biopsies of 12 healthy subjects (age 51.3 years, range 25-81) by incubation ...
Oguogho A - - 2000
(Iso)-eicosanoids appear to play a pivotal role in lymphatic contractility. Because prostaglandin (PG)I2, an arachidonic acid (20:4) metabolite, is a key substance generated by human lymphatics, both from exogenous and endogenous substrates, it is reasonable to assume that altered nutritional intake of precursor fatty acids (FA) influences formation of respective ...
Wagner F - - 2000
The filamentous fungus Penicillium olsonii secretes several polygalacturonases (PGs) with molecular masses of about 47 kDa. These enzymes consist of several basic and acidic isoforms, with dominant activities at pI 4.5 and pI 7.9. Two polygalacturonase genes, pg1 and pg2, have been cloned. The corresponding enzymes, PG1 and PG2, consist ...
Kiefer J R - - 2000
Cyclooxygenases are bifunctional enzymes that catalyse the first committed step in the synthesis of prostaglandins, thromboxanes and other eicosanoids. The two known cyclooxygenases isoforms share a high degree of amino-acid sequence similarity, structural topology and an identical catalytic mechanism. Cyclooxygenase enzymes catalyse two sequential reactions in spatially distinct, but mechanistically ...
Mansur A - - 2000
Nitric oxide (NO) is increased by gp120 in astrocytes and in monocyte-derived macrophages. Of the gp120 fragments (F1: amino acid 254-274, F2: amino acid 315-329, F3: amino acid 421-438), F1 has been shown to increase NO in astrocytes and gp120 also primes CD4+ T cells for apoptosis. Peripheral blood mononuclear ...
Llorente A - - 2000
Addition of arachidonic acid or stimulation of arachidonic acid production by secretory phospholipase A2 selectively upregulated apical endocytosis of ricin in MDCK cells without affecting basolateral endocytosis. Electron microscopic studies revealed that MDCK cells treated with secretory phospholipase A2 and incubated with horseradish peroxidase had an increased number of normal ...
Schneider C - - 2000
The initial and rate-limiting step in prostaglandin biosynthesis is stereoselective removal of the pro-S hydrogen from the 13-carbon of arachidonic acid. This is followed by oxygenation at C-11, formation of the five-membered ring, and a second oxygenation at C-15 to yield the endoperoxide product, prostaglandin G(2). Aspirin treatment of cyclooxygenase-2 ...
Cao Y Z - - 2000
Selenium (Se) is an integral part of the Se-dependent glutathione peroxidase (Se-GSH-Px) catalytic domain. By modulating the cellular levels of fatty acid hydroperoxides, Se-GSH-Px can influence key enzymes of arachidonic acid cascade, in this case cyclooxygenase (COX) and lipoxygenase (LOX). To investigate this phenomenon, the effects of cellular Se status ...
Daiber A - - 2000
We have previously shown that peroxynitrite (PN) selectively impaired prostacyclin (PGI2)-dependent vasorelaxation by tyrosine nitration of PGI2 synthase in an in situ model (Zou MH, Jendral M and Ullrich V, Br J Pharmacol 126: 1283-1292, 1999). By using this established model, we tested whether or not ebselen (2-phenyl-1,2-benzisoselenazol-3(2H)-one), which reacts ...
Belch J J - - 2000
Diets rich in arachidonic acid (20:4n-6) lead to the formation of 2-series prostaglandins (PGs) and 4-series leukotrienes (LTs), with proinflammatory effects. Nonsteroidal antiinflammatory drugs are used in rheumatoid arthritis to inhibit cyclooxygenase (prostaglandin-endoperoxide synthase), thereby decreasing production of 2-series PGs. Lipoxygenase activity remains intact, however, allowing LT production (eg, synthesis ...
Gogos C A - - 2000
The role of diet and certain nutritional factors in the etiology or promotion of various malignant diseases has widely been studied. A link between dietary fat and cancer has long been proposed through various human epidemiologic and experimental data. High fat diets are associated with a high incidence and accelerated ...
Kawakami S - - 2000
Prostaglandin E(1) (PGE(1) ) was incorporated in galactosylated liposomes containing cholesten-5-yloxy-N-(4-((1-imino-2-beta-D-thiogalactosyle thyl)amino)b utyl)formamide (Gal-C4-Chol) intended for hepatocyte-selective delivery. Liposomes composed of distearoylphosphatidylcholine (DSPC)/cholesterol (Chol)/Gal-C4-Chol (60∶35∶5) were prepared and compared with DSPC/Chol (60∶40) liposomes. After intravenous injection of [(3) H]-labeled PGE(1) or cholesteryl hexadecyl ether (CHE) with the liposomal formulation, mice ...
Mattos R - - 2000
Fats in the diet can influence reproduction positively by altering both ovarian follicle and corpus luteum function via improved energy status and by increasing precursors for the synthesis of reproductive hormones such as steroids and prostaglandins. Dietary fatty acids of the n-3 family reduce ovarian and endometrial synthesis of prostaglandin ...
Garavito R M - - 1999
Despite the marked differences in their physiological roles, the structures and catalytic functions of the cyclooxygenase isozymes COX-1 and -2 are virtually identical. Nevertheless, a handful of amino acid substitutions give rise to subtle differences in ligand binding between the two isoforms. These 'small' alterations of isozyme structure are sufficient ...
Gelderblom W C - - 1999
The mitoinhibitory effect of fumonisin B1 (FB1) on the mitogenic response of epidermal growth factor (EGF) was investigated in primary hepatocyte cultures with respect to the alterations in the omega6 fatty acid metabolic pathway. Fatty acid analyses of hepatocytes showed that EGF treatment resulted in a significant decrease in the ...
Koide M - - 1999
It is known that bone resorption is mediated by osteoclasts, and lipopolysaccharide (LPS) and inflammatory mediators such as interleukin-1 (IL-1) and prostaglandin E2 (PGE2) induce osteoclast differentiation from haemopoietic cells, 2-aminoethanesulphonic acid, which is known as taurine, is an important nutrient and is added to most synthetic human infant milk ...
Lee Y T - - 1999
Using the standard patch clamp whole cell recording method, we assessed the pharmacological activity of four fenamate nonsteroidal anti-inflammatory drugs, meclofenamic acid, flufenamic acid, mefenamic acid and niflumic acid, on hKv2.1, a major human neuronal voltage-gated potassium channel stably expressed heterologously in Chinese hamster ovary cells. Meclofenamic acid inhibited hKv2.1 ...
Roberts L J LJ - - 1999
The bicyclic endoperoxide prostaglandin (PG) H2 undergoes nonenzymatic rearrangement not only to PGE2 and PGD2, but also to levuglandins (LG) E2 and D2, which are highly reactive gamma-ketoaldehydes. Isoprostanes (IsoPs) are PG-like compounds that are produced by nonenzymatic peroxidation of arachidonic acid. PGH2-like endoperoxides are intermediates in this pathway. Therefore, ...
Saareks V - - 1999
The in vitro effects of nicotinic acid (10-1000 microM), pyridoxine (0.1-500 microM) and pyridoxal-5'-phosphate (0.1-500 microM) and the ex vivo effects of nicotinic acid (2500 mg orally during 12 h) and pyridoxine (600 mg orally daily for seven days) on arachidonic acid metabolism were investigated in calcium ionophore A23187 (calcimycin)-stimulated ...
Fujishima H - - 1999
We have used mice in which the gene for cytosolic phospholipase A2 (cPLA2) has been disrupted to demonstrate the absolute requirement for cPLA2 in both the immediate and the delayed phases of eicosanoid generation by bone marrow-derived mast cells. For the immediate phase, quantitative analysis of the products of the ...
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