title: Novel epicatechin derivatives with antioxidant activity modulate interleukin-1beta release in lipopolysaccharide-stimulated human blood.
abstract: We examine the potential antioxidant activity and the immune function of new epicatechin conjugates obtained by depolymerization of grape polymeric flavanols in the presence of cysteamine or cysteine. When incubated with an erythrocyte suspension, flavanols protected the erythrocyte membrane from hemolysis induced by 2,2'-azo-bis(2-amidinopropane)dihydrochloride (AAPH), an azo free radical initiator. The inhibitory effect was concentration-dependent and the IC50 was 119.8 microM for epicatechin, and 74.9 and 89.4 microM for the cysteine and cysteamine derivatives, respectively. These compounds were tested for their antioxidant activity and their capacity to modulate interleukin-1beta (IL-1beta), which is currently considered to be the major cytokine factor influencing the acute phase of the inflammatory response. At concentrations up to 20 microM, epicatechin and its derivatives inhibited the production of IL-1beta in whole blood incubated in the presence of E. coli lipopolysaccharide (LPS), in a concentration-dependent manner. The most active compound was the cysteamine derivative.
authors.affiliation: Dept. Fisiologia, Facultat de Farmàcia, Av. Joan XXIII s/n, Universitat de Barcelona, E-08028 Barcelona, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Mitjans
authors.forename: Verónica
authors.initials: V
authors.lastname: Martínez
authors.forename: Jaime
authors.initials: J
authors.lastname: del Campo
authors.forename: Celia
authors.initials: C
authors.lastname: Abajo
authors.forename: Carles
authors.initials: C
authors.lastname: Lozano
authors.forename: Josep Lluís
authors.initials: JL
authors.lastname: Torres
authors.forename: Maria Pilar
authors.initials: MP
authors.lastname: Vinardell
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D002392:Catechin / Q000031:analogs & derivatives / Q000737:chemistry / Q000494:pharmacology*; D003543:Cysteamine / Q000494:pharmacology; D003545:Cysteine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism; D004926:Escherichia coli; D005638:Fruit / Q000737:chemistry; D006801:Humans; D066298:In Vitro Techniques; D007375:Interleukin-1 / Q000096:biosynthesis* / Q000097:blood; D008070:Lipopolysaccharides / Q000494:pharmacology*; D012639:Seeds / Q000737:chemistry; D027843:Vitis / Q000737:chemistry
chemical_list: D000975:Antioxidants; D007375:Interleukin-1; D008070:Lipopolysaccharides; D003543:Cysteamine; D002392:Catechin; D003545:Cysteine