title: Using the pER8:GUS reporter system to screen for phytoestrogens from Caesalpinia sappan.
abstract: Arabidopsis thaliana pER8:GUS, a low-cost, highly efficient, and convenient transgenic plant system, was used to assay the estrogen-like activity of 30 traditional Chinese medicines. The MeOH extract of Caesalpinia sappan exhibited significant bioactivity in this assay, and subsequent bioactivity-guided fractionation of the extract led to the isolation of one new compound, (S)-3,7-dihydroxychroman-4-one (1), and 10 known compounds. Both the plant pER8:GUS and in vitro estrogen response element reporter assays were used to evaluate the estrogenic activity of the isolated compounds, and these two systems produced comparable results. Compounds 6, 8, and 11 showed significant estrogenic activity comparable to genistein. These active compounds were determined to be nontoxic new sources of phytoestrogens. In addition, compounds 2 and 3 inhibited ERE transcription induced by 17β-estradiol. A docking model revealed that compounds 6, 8, and 11 showed high affinity to the estrogen receptor. The pER8:GUS reporter system was demonstrated to be a useful and effective technique in phytoestrogen discovery.
authors.affiliation: Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan, Republic of China.
authors.forename: Wan-Chun
authors.initials: WC
authors.lastname: Lai
authors.forename: Hui-Chun
authors.initials: HC
authors.lastname: Wang
authors.forename: Guan-Yu
authors.initials: GY
authors.lastname: Chen
authors.forename: Juan-Cheng
authors.initials: JC
authors.lastname: Yang
authors.forename: Michal
authors.initials: M
authors.lastname: Korinek
authors.forename: Chia-Jung
authors.initials: CJ
authors.lastname: Hsieh
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nozaki
authors.forename: Ken-Ichiro
authors.initials: K
authors.lastname: Hayashi
authors.forename: Chih-Chung
authors.initials: CC
authors.lastname: Wu
authors.forename: Yang-Chang
authors.initials: YC
authors.lastname: Wu
authors.forename: Fang-Rong
authors.initials: FR
authors.lastname: Chang
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D029911:Caesalpinia / Q000378:metabolism*; D002867:Chromones / Q000032:analysis* / Q000737:chemistry / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000494:pharmacology*; D004958:Estradiol / Q000494:pharmacology; D004967:Estrogens / Q000032:analysis* / Q000494:pharmacology; D005260:Female; D019833:Genistein / Q000494:pharmacology; D056945:Hep G2 Cells; D006801:Humans; D008958:Models, Molecular; D015394:Molecular Structure; D048789:Phytoestrogens / Q000032:analysis* / Q000737:chemistry / Q000494:pharmacology; D030821:Plants, Genetically Modified / Q000235:genetics; D020845:Selective Estrogen Receptor Modulators / Q000494:pharmacology; D013624:Taiwan; D014934:Wood / Q000737:chemistry
chemical_list: C562119:(S)-3,7-dihydroxychroman-4-one; D002867:Chromones; D004365:Drugs, Chinese Herbal; D004967:Estrogens; D048789:Phytoestrogens; D020845:Selective Estrogen Receptor Modulators; D004958:Estradiol; D019833:Genistein