title: Alkaline phosphatase activity-guided isolation of active compounds and new dammarane-type triterpenes from Cissus quadrangularis hexane extract.
abstract: BACKGROUND
  The stem of Cissus quadrangularis L. (CQ) is used in traditional medicine to treat bone fractures and swelling. Anti-osteoporotic activity of CQ hexane extract has been reported, but the active compounds in this extract remain unknown. Thus, we aimed to identify the active compounds in CQ hexane extract using bioassay-guided isolation.
  
  
  METHODS
  The CQ hexane extract was fractionated sequentially with benzene, dichloromethane, ethyl acetate, and methanol. The examination of CQ extract and its fractions was guided by bioassays for alkaline phosphatase (ALP) activity during the differentiation of MC3T3-E1 osteoblastic cells. The cells were treated with or without the CQ extract and its fractions for a period of time, and then the stimulatory effect of the alkaline phosphatase enzyme, a bone differentiation marker, was investigated. The compounds obtained were structurally elucidated using spectroscopic techniques and re-evaluated for activity during bone differentiation.
  
  
  RESULTS
  A total of 29 compounds were isolated, viz., triterpenes, fatty acid methyl esters, glycerolipids, steroids, phytols, and cerebrosides. Four new dammarane-type triterpenes were isolated for the first time from nature, and this report is the first to identify this group of compounds from the Vitaceae family. Seven compounds, viz., glycerolipids and squalene, stimulated ALP activity at a dose of 10μg/mL. Moreover, the synergistic effect of these compounds on bone formation was demonstrated.
  
  
  CONCLUSIONS
  This report describes, for the first time, the isolation of active compounds from CQ hexane extract; these active compounds will be useful for the quality control of extracts from this plant used to treat osteoporosis.
authors.affiliation: Department of Pharmaceutical Botany, Faculty of Pharmacy, Mahidol University, 447 Sri-Ayuthaya Road, Rajathevi, Bangkok 10400, Thailand.
authors.forename: Thanika
authors.initials: T
authors.lastname: Pathomwichaiwat
authors.affiliation: Department of Anatomy, Faculty of Dentistry, Mahidol University, 6 Yothi Road, Rajathevi, Bangkok 10400, Thailand.
authors.forename: Pannee
authors.initials: P
authors.lastname: Ochareon
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Mahidol University, 447 Sri-Ayuthaya Road, Rajathevi, Bangkok 10400, Thailand.
authors.forename: Noppamas
authors.initials: N
authors.lastname: Soonthornchareonnon
authors.affiliation: National Center for Natural Products Research, University of Mississippi, Oxford, MS 38655, USA.
authors.forename: Zulfiqar
authors.initials: Z
authors.lastname: Ali
authors.affiliation: National Center for Natural Products Research, University of Mississippi, Oxford, MS 38655, USA; Department of Pharmacognosy, School of Pharmacy, University of Mississippi, Oxford, MS 38655, USA.
authors.forename: Ikhlas A
authors.initials: IA
authors.lastname: Khan
authors.affiliation: Department of Pharmaceutical Botany, Faculty of Pharmacy, Mahidol University, 447 Sri-Ayuthaya Road, Rajathevi, Bangkok 10400, Thailand. Electronic address: sompop.pra@mahidol.ac.th.
authors.forename: Sompop
authors.initials: S
authors.lastname: Prathanturarug
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism*; D001681:Biological Assay; D002478:Cells, Cultured; D032422:Cissus / Q000737:chemistry*; D004357:Drug Synergism; D006586:Hexanes / Q000737:chemistry*; D015394:Molecular Structure; D010006:Osteoblasts / Q000187:drug effects / Q000201:enzymology; D010012:Osteogenesis / Q000187:drug effects; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology*; D018547:Plant Stems / Q000737:chemistry; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D000097669:Dammaranes
chemical_list: D000469:Alkaline Phosphatase; D006586:Hexanes; D010936:Plant Extracts; D014315:Triterpenes; D000097669:Dammaranes; C026385:n-hexane
keywords: Dammarane; Osteoporosis; Synergy; Triterpenoids; Vitaceae