Search results for "Phorbol"

EFFECTS OF PHORBOL 12,13-DIACETATE AND ITS INFLUENCE ON SPASMOGENIC RESPONSES IN NORMAL AND SENSITIZED GUINEA-PIG TRACHEA

1995

Abstract We have studied the effects of phorbol 12,13-diacetate (PDA) and its influence on a variety of spasmogenic responses in trachea isolated in from normal and sensitized guinea-pigs. Tracheal preparations were denuded of epithelium, treated with indomethacin (2·8 μm), and cooled to 20°C. In these experimental conditions, tracheal strips contracted to PDA (0·1 nm-1 μm). Contractions to PDA (1 μm) were greater in sensitized tissues. In normal trachea, contractions to PDA (0·1 μm) were depressed by H-7, 1-(5-isoquinolinyl-sulphonyl)-2-methylpiperazine, (50 μm), amiloride (10 μm), verapamil (10 μm) and Ca2+-free exposure. Similar effects were obtained in sensitized trachea except that PDA…

Frequency-dependent effects of activation and inhibition of protein kinase C on neurohypophysial release of oxytocin and vasopressin

1989

Isolated rat neurohypophyses were superfused in vitro and the release of vasopressin and oxytocin into the medium was determined by specific radioimmunoassays. Hormone secretion was increased by electrical stimulation of the pituitary stalk at different frequencies. The effects of several phorbol esters, known to activate (phorbol 12,13-dibutyrate, PDB) or not to affect (4a-phorbol 12,13-dideconate and phorbol 12-monoacetate) protein kinase C, and of the direct protein kinase C inhibitor 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H7) were tested. Electrical stimulation with 450 pulses caused the release of about 45 μU vasopressin and 55 μU oxytocin, when a frequency of 3 Hz was applied…

Shedding of interleukin-6 receptor and tumor necrosis factor alpha. Contribution of the stalk sequence to the cleavage pattern of transmembrane prote…

2000

A functionally and structurally diverse group of transmembrane proteins including transmembrane forms of mediators or receptors can be proteolytically cleaved to form soluble growth factors or receptors. Recently, the proteolytic activity responsible for pro-tumor necrosis factor alpha (proTNFalpha) processing has been identified and named TACE (TNFalpha converting enzyme). In experiments with TACE deficient (TACE-/-) fibroblasts we found that 4beta-phorbol 12-myristate 13-acetate (PMA)-induced shedding of the interleukin-6 receptor (IL-6R) is strongly reduced. A basal hydroxamate sensitive release of IL-6R, however, could still be detected. This result demonstrates that TACE plays a role i…

Wip1 inhibition leads to severe pro-inflammatory phenotype in skin in response to chemical irritation

2016

Signal transduction pathways of membrane expression of proteinase 3 (PR‐3) in human endothelial cells

1997

At present, the exact mechanism of the pathogenic effect of anti-PR-3 antibodies remains unknown. Interaction of anti-neutrophil cytoplasmic antibodies (ANCAs) with human umbilical vein endothelial cells (HUVECs) may play a key role. Recently we were able to show that ANCAs recognize their target antigen, PR-3, translocated into the membrane of HUVECs. The objective of this study was to investigate regulation, i.e. signal transduction pathways, of PR-3 expression in endothelial cells. HUVECs were isolated according to the method of Jaffe et al. and cultured under standard conditions. A cyto-enzyme-linked immunosorbent assay (ELISA) with unfixed cells was performed. Membrane-expressed PR-3 w…

Phenylpropanoid and phenylisoprenoid metabolites from Asteraceae species as inhibitors of protein carbonylation.

2011

Abstract Three phenolic antioxidant and anti-inflammatory compounds: 7-methylaromadendrin, isoprenylhydroquinone glucoside, and 3.5-dicaffeoylquinic acid methyl ester, all isolated from Western Mediterranean Asteraceae species, have been studied for their inhibitory activity against protein carbonylation, a harmful post-translational modification of peptide chains associated with degenerative diseases. All compounds have proven to be effective, with 50% inhibitory concentration (IC 50 ) values in the micromolar range, against bovine serum albumin carbonylation caused by hypochlorite, peroxynitrite, and phorbol ester-induced leukocyte oxidative burst.

An Aqueous Extract of Ilex paraguariensis Reduces Carrageenan-Induced Edema and Inhibits the Expression of Cyclooxygenase-2 and Inducible Nitric Oxid…

2014

Mate (Ilex paraguariensis) is a highly popular herbal beverage in South America due to its high content of caffeine. Its hypolipidemic and antioxidant properties are of increasing interest in the treatment of cardiovascular disorders and for weight control. In the present study, we show for the first time both the local and systemic anti-inflammatory effects of an aqueous extract of mate in three classic in vivo models, namely acute and chronic 12-O-tetradecanoylphorbol 13-acetate-induced mouse ear edema and acute carrageenan-induced mouse paw edema. Caffeine, rutin, chlorogenic acid, 3,5-dicafeoyl quinic acid, and 4,5-dicafeoyl quinic acid, accompanied by a complex mixture of other simple …

Effects of polyphenols and lipids from Pennisetum glaucum grains on T-cell activation: modulation of Ca2+ and ERK1/ERK2 signaling

2015

International audience; BACKGROUND: Pearl millet (PM), i.e., Pennisetum glaucum, is widely grown in Africa and known for its anti-oxidant and anti-hyperlipidemic properties.METHODS: The P. glaucum grains were obtained from the region of Ouled Aïssa (South of Algeria). We assessed the effects of phenolic compounds and lipids, extracted from seeds of P. glaucum, on rat lymphocyte proliferation, activated by phorbol 12-myristate 13-acetate and ionomycin. In order to explore signaling pathway, triggered by these compounds, we assessed interleukin-2 (IL-2) mRNA expression and extracellular signal-regulated kinase-1/2 (ERK1/ERK2) phosphorylation. Finally, we determined increases in free intracell…

The transport activity of the human cationic amino acid transporter hCAT-1 is downregulated by activation of protein kinase C

2001

1 The human cationic amino acid transporter hCAT-1 contains several consensus sequences for phosphorylation by protein kinase C (PKC). This study investigates the eAect of PKC activation on hCAT-1-mediated transport. 2 When expressed in Xenopus laevis oocytes, hCAT-1-mediated L-arginine transport was reduced to 44+3% after a 30 min treatment of the oocytes with 100 nM phorbol-12-myristate-13-acetate (PMA). 4a-phorbol-12,13-didecanoate (4a-PDD, 100 nM) had no eAect. 3 In EA.hy926 endothelial cells, maximal inhibition of hCAT-1-mediated L-arginine transport (to 3‐11% of control) was observed after treatment of the cells with 100 nM PMA for 4 h. A 20‐30 h exposure of the cells to 100 nM PMA le…

In vivo activity of pseudoguaianolide sesquiterpene lactones in acute and chronic inflammation.

2000

The pseudoguaianolide sesquiterpene lactones 4-alpha-O-acetyl-pseudoguaian-6beta-olide (1), hymenin (2), ambrosanolide (3), tetraneurin A (4), parthenin (5), hysterin (6) and confertdiolide (7) were evaluated for their ability to affect the inflammation responses induced by different agents. All the compounds showed activity against the 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced mouse ear edema. The ethyl phenylpropiolate (EPP)-induced mouse ear edema was inhibited by compounds 3, 5 and 7. However, when sesquiterpene-lactones were assayed on the arachidonic acid (AA)-induced mouse ear edema, none of them were active. The only sesquiterpene lactone orally active against the paw mouse…