title: Drastic effect of several caffeic acid derivatives on the induction of heme oxygenase-1 expression revealed by quantitative real-time RT-PCR.
abstract: Among antioxidative polyphenols, caffeic acid esters such as caffeic acid phenethyl ester (CAPE) and chlorogenic acid are contained in propolis, vegetables and coffee. In this study, we compared the efficacy of some polyphenols on the activation level of a cytoprotective heme oxygenase-1 (HO-1) gene in RAW264.7 mouse macrophage cells using quantitative real-time RT-PCR. The quantitative study revealed a variety of activation level of HO-1 gene by the chemicals. CAPE and caffeic acid ethyl ester (CAEE) at the final concentration of 2 muM drastically activated the HO-1 gene to 39.2-fold and 20.1-fold, respectively. Curcumin, structurally related with caffeic acid and an element of turmeric, induced the HO-1 gene to 5.8-fold. In contrast, no activation was observed by other caffeic acid esters such as chlorogenic acid and rosmarinic acid. Higher concentrations were necessary for the activation by an antioxidant cysteamine and the electrophile diethyl maleate. Although the inducible activities of CAPE and chlorogenic acid were distinctly different, they showed similar reductive capacities when determined by cyclic voltammetry. These results show that the drastic activation of HO-1 gene by CAPE and CAEE is dependent upon their chemical structures, rather than the reductive activity of polyphenols, possibly reflecting the physiological effects of the nutritional elements.
authors.affiliation: Department of Radiation Emergency Medicine, National Institute of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba, 263-8555, Japan. suzuki_q@nirs.go.jp
authors.forename: Keiko
authors.initials: K
authors.lastname: Suzuki
authors.forename: Izumi
authors.initials: I
authors.lastname: Tanaka
authors.forename: Ikuo
authors.initials: I
authors.lastname: Nakanishi
authors.forename: Ayako
authors.initials: A
authors.lastname: Kurematsu
authors.forename: Haruko
authors.initials: H
authors.lastname: Yakumaru
authors.forename: Nobuo
authors.initials: N
authors.lastname: Ikota
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ishihara
mesh_terms: D000818:Animals; D002109:Caffeic Acids / Q000494:pharmacology*; D002460:Cell Line; D045744:Cell Line, Tumor; D004790:Enzyme Induction / Q000187:drug effects; D051547:Heme Oxygenase-1 / Q000096:biosynthesis*; D006801:Humans; D051379:Mice; D010626:Phenylethyl Alcohol / Q000031:analogs & derivatives* / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D002109:Caffeic Acids; D012333:RNA, Messenger; C032773:ethyl caffeate; D051547:Heme Oxygenase-1; C055494:caffeic acid phenethyl ester; D010626:Phenylethyl Alcohol