title: Effects of catechin on homocysteine metabolism in hyperhomocysteinemic mice.
abstract: We have recently focused on the interaction between hyperhomocysteinemia, defined by high plasma homocysteine levels, and paraoxonase-1 expression and found a reduced activity of paraoxonase-1 associated with a reduced gene expression in the liver of cystathionine beta synthase (CBS) deficient mice, a murine model of hyperhomocysteinemia. As it has been demonstrated that polyphenolic compounds could modulate the expression level of the paraoxonase-1 gene in vitro, we have investigated the possible effect of flavonoid supplementation on the impaired paraoxonase-1 gene expression and activity induced by hyperhomocysteinemia and have evaluated the link with homocysteine metabolism. High-methionine diet significantly increased serum homocysteine levels, decreased hepatic CBS activity, and down-regulated paraoxonase-1 mRNA and its activity. However, chronic administration of catechin but not quercetin significantly reduced plasma homocysteine levels, attenuated the reduction of the hepatic CBS activity, and restored the decreased paraoxonase-1 gene expression and activity induced by chronic hyperhomocysteinemia. These data suggest that catechin could act on the homocysteine levels by increasing the rate of catabolism of homocysteine.
authors.affiliation: EA 3508, Université Paris 7-Denis Diderot, Case 7104, 2 Place Jussieu, 75251 Paris Cedex 05, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Hamelet
authors.forename: Karine
authors.initials: K
authors.lastname: Demuth
authors.forename: Julien
authors.initials: J
authors.lastname: Dairou
authors.forename: Aurélie
authors.initials: A
authors.lastname: Ledru
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Paul
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Dupret
authors.forename: Jean-Maurice
authors.initials: JM
authors.lastname: Delabar
authors.forename: Fernando
authors.initials: F
authors.lastname: Rodrigues-Lima
authors.forename: Nathalie
authors.initials: N
authors.lastname: Janel
mesh_terms: D000284:Administration, Oral; D000821:Animal Feed; D000818:Animals; D002392:Catechin / Q000494:pharmacology*; D003541:Cystathionine beta-Synthase / Q000235:genetics; D017931:DNA Primers; D006710:Homocysteine / Q000378:metabolism*; D020138:Hyperhomocysteinemia / Q000235:genetics / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D008715:Methionine / Q000008:administration & dosage / Q000494:pharmacology; D051379:Mice; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013482:Superoxide Dismutase / Q000235:genetics; D000072105:Superoxide Dismutase-1
chemical_list: D017931:DNA Primers; D006710:Homocysteine; D012313:RNA; D002392:Catechin; D008715:Methionine; C000606291:Sod1 protein, mouse; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1; D003541:Cystathionine beta-Synthase