Impact on the bowel of amtolmetin guacyl, a new gastroprotective non-steroidal anti-inflammatory drug.

Amtolmetin guacyl (MED15) is a new non-steroidal anti-inflammatory drug (NSAID) which shares anti-inflammatory, analgesic and antipyretic activity with the other drugs of the NSAID family but which shows, unexpectedly, strong gastroprotective activity similar to misoprostol. This effect has been attributed to the presence in its molecule of a vanillic moiety responsible for stimulation of capsaicin receptors present throughout the length of the gastrointestinal tract. MED15 shows antispasmodic activity in the bowel against a number of agonists and compares favourably with reference compounds.

Anti-inflammatory and antiplatelet effects of amtolmetin guacyl, a new gastroprotective non-steroidal anti-inflammatory drug.

Amtolmetin guacyl (CAS 873344-06-7, MED 15) is a non-steroidal anti-inflammatory drug (NSAID) which has shown gastroprotective effects attributable to capsaicin receptor stimulation through the presence of a vanillic moiety in its molecular structure. The present paper further defines the anti-inflammatory activity of the product in an exudative rat model and in an arthritic rat model. The results obtained from both studies demonstrate anti-inflammatory effects comparable to those of the traditional NSAIDs in use.

The mechanism of action of amtolmetin guacyl, a new gastroprotective nonsteroidal anti-inflammatory drug.

Amtolmetin guacyl (2-methoxyphenyl-1-methyl-5-p-methylbenzoyl-pyrrol-2-acetamido acetate) (MED15) is a new nonsteroidal anti-inflammatory drug (NSAID) with anti-inflammatory, analgesic and antipyretic properties similar to the traditional drugs, but with unexpected gastroprotective effects. In an in vivo rat model, amtolmetin guacyl administered orally demonstrates inhibition of gastric acid secretion following stimulation by various agonists, and up-regulation of gastric bicarbonate production. Pretreatment with MED15 also shows a significant reduction of indomethacin-induced gastric damage in the rat.

Antiplatelet effect of a new inhibitor of thromboxane synthase and thromboxane A2 receptors.

The effect on platelets of a new molecule denominated MED 27 (1-methyl-5-(4-methylbenzoyl)pyrrole-2-acetic acid 2-(theophylline-7-yl)ethyl ester, CAS 104333-87-1) was investigated. In vitro in the rat and using scalar doses of adenosine 5-diphosphate as challenge, the substance was found to be a platelet antiaggregating agent; in human platelets this effect was also found using stimuli such as epinephrine, collagen, arachidonic acid (AA), platelet aggregating factor (PAF) and U46619 (15-hydroxy-11 alpha,9 alpha-epoxymethanoprosta-5,13-dienoic acid). MED 27 ex vivo induced a dose-dependent inhibition of rat platelet aggregation at doses much lower than that of acetylsalicylic acid (ASA).

Effect of a new de-N-acetyl-lysoglycosphingolipid on some tumour models.

A new de-N-acetylated glycosphingolipid termed WILD20, a breakdown product of GM1 obtained through alkaline hydrolysis, and characterized by nuclear magnetic resonance, mass spectrometry and elementary analysis, was found to inhibit phospholipase A2 via phosphokinase C translocation blockade. The substance inhibited various tumour cell lines in vitro, in synergy with doxorubicin and cisplatin. In vivo, it showed an antitumoral effect when both the tumour cells and WILD20 were injected at the same site (peritoneal cavity).

Studies on the gastric tolerability of the new non-steroidal anti-inflammatory drug amtolmetin guacyl.

Unexpectedly high levels of gastric tolerance to the new non-steroidal anti-inflammatory drug (NSAID) amtolmetin guacyl (CAS 87344-06-7, MED15) were observed in clinical practice. Further investigation of the drug was, therefore, undertaken in order to evaluate its gastrointestinal side-effects in animals. This new agent, which possesses high anti-inflammatory, analgesic and antipyretic activity, was recently introduced into medical therapy.

In vitro and in vivo impact of a new glycosphingolipid on neutrophils.

A new water-soluble, orally absorbable de-N-acetyl-lysoganglioside (WILD20), breakdown product of the monosialoganglioside GM1, was found to influence some parameters of neutrophil response to inflammation stimuli. Superoxide anion production appears inhibited, along with neutrophil killing properties. A block of both pathways of arachidonic acid cascade and PAF was also found, as well as neutrophil ICAM-1-mediated adhesion to endothelial cells.

Induction of the nitric oxide-synthesizing pathway in fresh and interleukin 2-cultured rat natural killer cells.

Several lines of evidence suggest that nitric oxide (NO), generated through nitric oxide synthase (NOS) by cleavage of terminal guanidino nitrogen from L-arginine, mediates tumor cell killing by mononuclear phagocytes. Natural killer (NK) cells are cytotoxic effector cells that lyse a variety of tumor and virus-infected cells in a MHC-unrestricted manner. NK cells cultured with interleukin 2 proliferate and acquire the ability to lyse a wide range of targets, including NK-resistant tumor cells (LAK activity).

Effect of a new de-N-acetyl-lysoglycosphingolipid on chemically-induced inflammatory bowel disease: possible mechanism of action.

A new, orally active de-N-acetylated lysoglycosphingolipid (WILD20) was evaluated as antiinflammatory agent using a model of chemically-induced inflammatory bowel disease (IBD) in the rat to mimic human ulcerative colitis and Chron's disease. IBD was induced by hapten trinitrobenzenesulphonic acid (TNB). WILD20, orally administered as preventive or curative, was demonstrated to be efficacious at daily dosages of 0.

Preparation and characterization of four new variously deacetylated lysogangliosides, breakdown products of GM1.

Four new deacylated lysogangliosides were obtained through alkaline hydrolysis of either C18 or C20 sphingosine homologues of GM1. By this procedure, both the fatty acids residue and the N-acetyl group of sialic acid were removed to give mono-N-acetyl-lysoGM1 (C18 and C20); the additional loss of the N-acetyl group of the acetylgalactosamine moiety gave de-N-acetyl-lysoGM1 (C18 and C20) with three free amino groups. The structures of four deacetylated lysogangliosides were unambiguously characterized by chemical analysis and 1H and 13C NMR spectroscopy as well as by negative ion FABMS.

Antiplatelet effects of a new de-N-acetyl-lyso-glycosphingolipid.

Gal beta 1-->3GalN beta 1-->4Gal(3<--2 alpha Neu)beta 1-->4Glc beta-->1Sph (WILD20), a new glycosphingolipid, a breakdown product of the monosialoganglioside GM1 obtained through alkaline hydrolysis, shows dose-dependent platelet anti-aggregating properties in vitro and in vivo. This effect is agonist- and species-independent. The family of lysosphingolipids, to which the compound belongs, is present in platelets particularly after thrombin treatment.

In vivo cocaine administration influences lymphokine production and humoral immune response.

The effect of in vivo cocaine administration on in vitro mitogen-induced lymphokine production was examined. Splenocyte cultures from BALB/c mice treated with an acute (1 mg/kg) or daily cocaine administration (1 mg/kg/day for 7 consecutive days) were less responsive to induction of IFN-gamma, IL-2 and IL-4 production by mitogen stimuli. We also evaluated the humoral immune response to both a T-dependent (HEL) and a T-independent antigen (rHBcAg).

Demonstration of the formation of hydroxyl radicals in acute myocardial infarction in man using salicylate as probe.

Dihydroxybenzoic acid (DHBA) derivatives of acetylsalicylic acid (ASA) are formed in vivo by the action of the hydroxyl radical (OH.). In order to evaluate the possible formation of OH(.

Inhibition of rat fibroblast cell proliferation at specific cell cycle stages by cocaine.

We have analyzed the role of cocaine in the control of the rat fibroblast (EL2) cell proliferation. Our data show a dose-related effect on the inhibition of DNA synthesis and cell growth when cocaine is added with serum or with a pure growth factor [Epidermal Growth Factor (EGF)]. Pretreatment by drug did not appreciably enhance the inhibition of S-phase entry above that obtained when cocaine and mitogen were added simultaneously.

Enhancement of lymphocyte proliferation and IL-2 receptor expression by a processed form (GM-1/P) of monosialoganglioside GM-1.

In this study we investigated the ability of GM-1/P, a calcium mediated processed form of monosialoganglioside GM-1, of in vivo augmenting mouse T and B-lymphocyte blastogenesis induced by mitogens. We have also determined its effect on IL-2 responsiveness by analyzing the induction of the expression of IL-2 receptor (IL-2r) on mouse spleen cells. Lymphocyte blastogenesis was evaluated by 3H-TdR incorporation of spleen cells from untreated or GM-1/P (1mg/Kg, i.

Augmentation of mouse natural killer (NK) activity by GM-1/P, a processed form of monosialoganglioside GM-1.

We describe the immunomodulatory activity of GM-1/P a processed form of GM-1 (monosialoganglioside) extracted from ox brain, purified and physically modified. We examined the effect of in vivo and in vitro treatment of GM-1/P on natural (NK) activity and its ability to induce the production of interleukin-2 (IL-2) in the mouse. In vivo treatment with GM-1/P (1 mg/Kg, i.

Effect of acute or daily cocaine administration on cellular immune response and virus infection in mice.

The effects of in vivo cocaine administrations on cellular cytotoxicity were studied. Cocaine induced a dose-related immunosuppression of natural killer cell activity, with maximal depression at 1-5 mg/kg. In addition, the degree of inhibition following a single intraperitoneal (i.

Methadone vs morphine: comparison of their effect on phagocytic functions.

A comparison of the effects of methadone and morphine on phagocytic physiology was carried out in mice, using a number of tests, to estimate the risk of using methadone in maintenance protocols for opiates addicts. Results indicate that methadone, like morphine, reduces (a) R.E.

Morphine and methadone impact on human phagocytic physiology.

Human subjects submitted to treatment with morphine show a severe depression of phagocytosis, killing properties and superoxide production both of their polymorphonuclear leukocytes and monocytes. Polymorphonuclear leukocyte adherence, chemotaxis, random migration, myeloperoxidase content, lysozyme content and lymphocyte Rosette E formation were poorly influenced. Methadone-treated subjects show a similar effect at phagocytic level but far less evident.

Effect of morphine on resistance to infection.

Morphine was demonstrated to exacerbate infections. Experiments were performed to evaluate variations of phagocytic physiology during morphine treatment. In mice, morphine drastically reduced reticuloendothelial system activity, phagocyte count, phagocytic index, killing properties, and superoxide anion production in polymorphonuclear leukocytes and macrophages.

Influence of cortisone and cyclophosphamide on xanthine oxidase bacterial activation.

The xanthine oxidase increase in mice liver as response to infection was studied as a possible parameter useful for a better understanding of theimmunosuppression due to cyclophosphamide and cortisone. An impact of cortisone but not of cyclophosphamide on this mechanism was found; this may be useful in order to discriminate between the two different types of immunosuppressive drugs.