ABSTRACT
The mechanisms by which food allergens are absorbed and sensitized via the gastrointestinal tract have not been well characterized. In this study, the gastrointestinal absorption of a major soybean allergen, Gly m Bd 30K, in young and older mice, and the effects of dietary fat and exogenous emulsifier were investigated. In Expt. 1, Gly m Bd 30K [0, 500 or 2000 mg/kg body weight (BW)] was administered orally to 24-d-old mice, and blood was sampled at various time points over a 120-min period. Plasma Gly m Bd 30K was measured by sandwich ELISA and immunoblotting. Its concentration peaked at 30 min and was dose dependent. Intact Gly m Bd 30K and its 20-kDa fragments were identified in plasma after absorption. In Expt. 2, 24-d-old mice administered soy milk containing 1 mg Gly m Bd 30K showed a steady increase in plasma Gly m Bd 30K from 60 to 120 min that was significantly higher than that in 10-wk-old mice. In Expt. 3, when corn oil (5 or 30%) was coadministered with Gly m Bd 30K (2000 mg/kg BW) to 24-d-old mice, the plasma concentration increased significantly and generally reached a plateau after 30 min. The absorption after the coadministration of 30% corn oil and 3% sucrose fatty acid ester was higher than after the administration of 30% corn oil alone. Intact Gly m Bd 30K and its fragments that were < 20 kDa survived digestion and were absorbed into the blood. We propose that absorption was enhanced by fat carrier-mediated transport.
Subject(s)
Dietary Fats/pharmacology , Emulsifying Agents/pharmacology , Intestinal Absorption/physiology , Plant Proteins/pharmacokinetics , Allergens , Animals , Antigens, Plant , Kinetics , Male , Mice , Mice, Inbred Strains , Soy Milk , Soybean Proteins , Time Factors , Tissue DistributionABSTRACT
In the course of our characterization studies on anti-obese and antidiabetogenic principles in medicinal foodstuffs, we found that the methanolic extract from the stems of Salacia chinensis (Hippocerateaceae) showed potent anti-hyperglycemic effects in oral sucrose or maltose-loaded rats, inhibitory effects on intestinal alpha-glucosidase, rat lens aldose reductase, formation of Amadori compounds and advanced glycation end-products, nitric oxide production from lipopolysaccharide-activated mouse peritoneal macrophage, and radical scavenging activities. Those in vivo and in vitro biological activities were compared with those of S. oblonga and S. reticulata. In addition, we isolated the principal alpha-glucosidase inhibitor, salacinol, from the stems of S. chinensis and examined alpha-glucosidase inhibitory activities of eleven samples of S. chinensis collected in Thailand.
Subject(s)
Glycoside Hydrolase Inhibitors , Hippocrateaceae/chemistry , Sugar Alcohols/isolation & purification , Sugar Alcohols/pharmacology , Sulfates/isolation & purification , Sulfates/pharmacology , Aldehyde Reductase/antagonists & inhibitors , Animals , Bacterial Proteins/metabolism , Carrier Proteins/metabolism , Free Radical Scavengers/metabolism , Glycation End Products, Advanced/metabolism , Hypoglycemic Agents , Intestines/enzymology , Intracellular Signaling Peptides and Proteins , Lens, Crystalline/enzymology , Macrophages, Peritoneal/metabolism , Male , Mice , Nitric Oxide/metabolism , Quality Control , Rats , Rats, Wistar , ThailandABSTRACT
The methanolic extract of the roots of Saussurea lappa CLARKE, a Chinese medicinal herb Saussureae Radix, was found to inhibit nitric oxide (NO) production in lipopolysaccharide (LPS)-activated mouse peritoneal macrophages. Among the constituents from the methanolic extract, two sesquiterpene lactones (costunolide and dehydrocostus lactone) and two amino acid-sesquiterpene conjugates (saussureamines A and B) potently inhibited LPS-induced NO production (IC(50)=1.2-2.8 microM). Saussureamines A and B in addition to costunolide and dehydrocostus lactone did not inhibit iNOS enzyme activity, but they inhibited both induction of inducible NO synthase and activation of nuclear factor-kappaB in accordance with induction of heat shock protein 72.
