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1. Ilex aquifolium: Protection Against Enzymatic and Non-Enzymatic Lipid Peroxidation

Author

D. H. Paper, Klaus Müller, and Klaus Ziereis

Subjects
Antioxidant, Neutrophils, Leukotriene B4, Rutin, medicine.medical_treatment, Pharmaceutical Science, Hyperoside, Mice, Inbred Strains, Analytical Chemistry, Lipid peroxidation, Mice, chemistry.chemical_compound, Biosynthesis, Chlorogenic acid, Drug Discovery, medicine, Animals, 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid, Lipoxygenase Inhibitors, Hydrogen peroxide, Skin, Brain Chemistry, Flavonoids, Pharmacology, Arachidonate 5-Lipoxygenase, Plants, Medicinal, Plant Extracts, Organic Chemistry, Complementary and alternative medicine, chemistry, Biochemistry, Deoxyribose, Liposomes, Molecular Medicine, Cattle, Female, Quercetin, Lipid Peroxidation, Medicine, Traditional, Chlorogenic Acid
Abstract

The ethanolic extract of Ilex aquifolium L. (Aquifoliaceae) concentration-dependently inhibited leukotriene B4 biosynthesis in isolated bovine PMNL with an IC50 value of about 60 micrograms/ml, whereas the effect on epidermal 12(S)-HETE biosynthesis was much less pronounced. The extract also inhibited the non-enzymatic, peroxyl radical-stimulated lipid peroxidation in model membranes and was further a scavenger of the iron-dependent generation of hydroxyl radicals from hydrogen peroxide as determined by protection against deoxyribose degradation. While inhibition of leukotriene biosynthesis was not mediated by its known phenolic constituents such as hyperoside, rutoside, and chlorogenic acid, these compounds were responsible for the inhibitory effects of I. aquifolium against non-enzymatic lipid peroxidation and deoxyribose degradation.

Published
1998

2. Intestinal Inflammation Increases Gastrointestinal Threonine Uptake and Mucin Synthesis in Enterally Fed Minipigs.

Author

Rémond, Didier, Buffière, Caroline, Godin, Jean-Philippe, Mirand, Philippe Patureau, Obled, Christiane, Paper, Isabelle, Dardevet, Dominique, Williamson, Gary, Breuillé, Denis, and Faure, Magali

Subjects
BIOSYNTHESIS, INFLAMMATORY bowel diseases, GASTROINTESTINAL system, GLYCOPROTEINS, MUCINS, SULFONIC acids, ILEUM, NUTRIENT interactions, NUTRIENT uptake
Abstract

The high requirement of the gut for threonine has often been ascribed to the synthesis of mucins, secreted threonine-rich glycoproteins protecting the intestinal epithelium from injury. This requirement could be even greater during intestinal inflammation, when mucin synthesis is enhanced. In this study, we used an animal model to investigate the effects of an acute ileitis on threonine splanchnic fluxes. Eight adult multi-catheterized minipigs were fed with an enteral solution. Four of them were subjected to experimental ileitis involving direct administration of trinitrobenzene sulfonic acid (TNBS) into the ileum (TNBS-treated group) and the other 4 were not treated (control group). Threonine fluxes across the portal-drained viscera (PDV) were quantified with the use of simultaneous i.g. L-[15Nithreonine and iv. L-[U-13C]threonine infusions. Ileal mucosa was sampled for mucin fractional synthesis rate measurement, which was greater in the TNBS-treated group (114 ± 15%/d) than in the control group (61 ± 8%/d) (P= 0.021). The first-pass extraction of dietary threonine by the PDV and liver did not differ between groups and accounted for ∼27 and 10% of the intragastric delivery, respectively. PDV uptake of arterial threonine increased from 25 ± 14 μmol·kg-1· h-1 in the control group to 171 ± 35 μmoI·kg-1· h-1 in the TNBS-treated group (P < 0.001). In conclusion, ileitis increased intestinal mucin synthesis and PDV utilization of threonine from arterial but not luminal supply. This leads to the mobilization of endogenous proteins to meet the increased threonine demand associated with acute intestinal inflammation. [ABSTRACT FROM AUTHOR]

Published
2009
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