Immunomodulatory activity of a new family of antioxidants obtained from grape polyphenols.

We examined the potential antioxidant activity and the immunopharmacological activity of new epicatechin conjugates obtained by depolymerization of grape polymeric flavanols in the presence of cysteamine or cysteine and with or without gallate. The compounds studied were (-)-epicatechin (1), cysteinyl-epicatechin (2), cysteamine-epicatechin (3), (-)-epicatechin gallate (4), cysteinyl-epicatechin gallate (5), and cysteamine-epicatechin gallate (6) When incubated with an erythrocyte suspension, flavanols protected the erythrocyte membrane from hemolysis induced by 2,2'-azobis(2-amidinopropane) dihydrochloride, an azo free-radical initiator. All the epicatechin derivatives tested were more efficient as antioxidant than epicatechin.

Novel epicatechin derivatives with antioxidant activity modulate interleukin-1beta release in lipopolysaccharide-stimulated human blood.

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.

In vitro study of the antioxidant and immunomodulatory activity of aqueous infusion of Bidens pilosa.

Bidens pilosa is an annual plant from tropical America with anti-inflammatory properties in hepatitis, laryngitis, headache and digestive disorders, among others. Its wide pharmacological applications can be attributed to its chemical composition, with inhibitory effects on pathogenic microorganisms and flavonoids, which show strong antioxidant capacities. We investigated the antioxidant activity of an aqueous infusion of Bidens pilosa by studying its protective effect on the hemolysis induced by an initiator of radicals such as 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH).