title: Isolation and identification of cucurbitane-type triterpenoids with partial agonist/antagonist potential for estrogen receptors from Momordica charantia.
abstract: This study aims at investigating the estrogenic activity and active cucurbitane-type triterpenoid compounds of bitter gourd (Momordica charantia, MC) using a transactivation assay for estrogen receptors (ER) α and β. The lyophilized fruits of MC were exhaustively extracted with ethyl acetate (EA) and 95% ethanol (EtOH), sequentially. The nonsaponifiable fraction (NS) of the EA extract as well as the acid hydrolyzed EtOH extract (AH) was fractionated and isolated by repeated column chromatography and further purified by preparative HPLC or RP-HPLC. One known compound, 5β,19-epoxycucurbita-6,24-diene-3β,23ξ-diol (6), was isolated from the NS, and five new compounds (1-5) were isolated from AH and identified as cucurbita-6,22(E),24-trien-3β-ol-19,5β-olide (1), 5β,19-epoxycucurbita-6,22(E),24-triene-3β,19-diol (2), 3β-hydroxycucurbita-5(10),6,22(E),24-tetraen-19-al (3), 19-dimethoxycucurbita-5(10),6,22(E),24-tetraen-3β-ol (4), and 19-nor-cucurbita-5(10),6,8,22(E),24-pentaen-3β-ol (5). In the noncytotoxic concentration range, compounds 1, 2, 5 and 6 showed weak agonistic activity via ER α and β. Compounds 1, 2, 3 and 6 significantly antagonized the transactvation of 17β-estradiol (E(2)) via both ER α and β. In conclusion, this study demonstrates, for the first time as far as we know, the partial agonist/antagonist activity via ER of four new and one known cucurbitane-type triterpenoids from MC. Further studies are worthy to explore the selective estrogen receptor modulator (SERM) activity of MC.
authors: Department of Biochemical Science and Technology, National Taiwan University, Tapei, Taiwan.
authors: Chin
authors: C
authors: Hsu
authors: Chin-Lin
authors: CL
authors: Hsieh
authors: Yueh-Hsiung
authors: YH
authors: Kuo
authors: Ching-jang
authors: CJ
authors: Huang
mesh_terms: D002460:Cell Line; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D029777:Momordica charantia / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D011960:Receptors, Estrogen / Q000819:agonists* / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D015533:Transcriptional Activation / Q000187:drug effects; D014315:Triterpenes / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D010936:Plant Extracts; D011960:Receptors, Estrogen; D014315:Triterpenes