title: Ponicidin and oridonin are responsible for the antiangiogenic activity of Rabdosia rubescens, a constituent of the herbal supplement PC SPES.
abstract: Antiangiogenic activity has been identified in an aqueous EtOH extract of Rabdosia rubescens, a component of the dietary supplement PC SPES. Bioassay-guided fractionation using a novel in vitro human endothelial cell-based assay for angiogenesis afforded the diterpenoids ponicidin (1) and oridonin (2), with significant antiangiogenic activity at subcytotoxic concentrations, suggesting that these constituents may strongly contribute to the demonstrated clinical efficacy of PC SPES as a treatment for advanced prostate cancer.
authors.affiliation: Southwest Center for Natural Products Research and Commercialization, Office of Arid Lands Studies, College of Agriculture and Life Sciences, University of Arizona, 250 E. Valencia Road, Tucson, AZ 85706-6800, USA.
authors.forename: Linda C
authors.initials: LC
authors.lastname: Meade-Tollin
authors.forename: E M Kithsiri
authors.initials: EM
authors.lastname: Wijeratne
authors.forename: Deborah
authors.initials: D
authors.lastname: Cooper
authors.forename: Mischa
authors.initials: M
authors.lastname: Guild
authors.forename: Edlyn
authors.initials: E
authors.lastname: Jon
authors.forename: Anne
authors.initials: A
authors.lastname: Fritz
authors.forename: Guang-Xiong
authors.initials: GX
authors.lastname: Zhou
authors.forename: Luke
authors.initials: L
authors.lastname: Whitesell
authors.forename: Jing-Yu
authors.initials: JY
authors.lastname: Liang
authors.forename: A A Leslie
authors.initials: AA
authors.lastname: Gunatilaka
mesh_terms: D020533:Angiogenesis Inhibitors / Q000627:therapeutic use*; D000972:Antineoplastic Agents, Phytogenic / Q000627:therapeutic use*; D002478:Cells, Cultured; D004224:Diterpenes / Q000494:pharmacology*; D045786:Diterpenes, Kaurane; D004365:Drugs, Chinese Herbal / Q000627:therapeutic use*; D042783:Endothelial Cells / Q000187:drug effects; D006801:Humans; D006868:Hydrolysis; D020128:Inhibitory Concentration 50; D037602:Isodon / Q000737:chemistry*; D008297:Male; D015394:Molecular Structure; D011471:Prostatic Neoplasms / Q000188:drug therapy*
chemical_list: D020533:Angiogenesis Inhibitors; D000972:Antineoplastic Agents, Phytogenic; D004224:Diterpenes; D045786:Diterpenes, Kaurane; D004365:Drugs, Chinese Herbal; C114209:herbal preparation PC-SPES; C011959:oridonin; C090365:ponicidin