title: Inhibition of arachidonic acid metabolism by the Andean crude drug Parastrephia lucida (Meyen) Cabrera.
abstract: BACKGROUND
  Parastrephia lucida (Meyen) Cabrera is used in the traditional medicine of Argentinean highlands as an antiseptic and anti-inflammatory medicinal plant. To give scientific support to the ethnopharmacological claim of Parastrephia lucida as an anti-inflammatory crude drug the effect of Parastrephia lucida extracts and fractions was assessed on key enzymes of the biosynthesis of pro-inflammatory eicosanoids mediators from arachidonic acid (AA).
  
  
  METHODS
  A bio-guided fractionation of the plant extract was carried out to find out the compounds or mixtures responsible for the anti-inflammatory effect. The extracts and fractions were tested in vitro for their ability to inhibit the enzymes cyclooxygenase (COX)-1 and COX-2, lipoxygenase (LOX) and phospholipase (sPLA2). Fractions were analyzed by HPLC-MS, HPLC-ESI-MS/MS and NMR to relate the effect with groups of secondary metabolites.
  
  
  RESULTS
  Parastrephia lucida was more effective inhibiting COX and sPLA2 than LOX. Assay-guided isolation led to the active fractions C and F which showed different effect on the selected enzymes. The fraction C was more effective inhibiting LOX while fraction F showed better activity against sPLA2 and COX-2. Both fractions were further worked-up following the isolation of the anti-inflammatory agents with the selected enzyme assays. The main compounds identified in the most active fractions were 5,4′-dihydroxi-7-methoxyflavanone, apigenin, apigenin methyl ether and apigenin trimethyl ether, methyl and dimethyl ethers from quercetin, kaempferol and luteolin methyl ether, ferulic acid esters, cinnamic acid and vanillin.
  
  
  CONCLUSIONS
  Parastrephia lucida extract inhibit AA metabolism via several enzymes. The results give support to the traditional use of this plant for the treatment of inflammatory disorders.
authors.forename: Romina E
authors.initials: RE
authors.lastname: D'Almeida
authors.forename: María I
authors.initials: MI
authors.lastname: Isla
authors.forename: Elina de L
authors.initials: Ede L
authors.lastname: Vildoza
authors.forename: Cristina
authors.initials: C
authors.lastname: Quispe
authors.forename: Guillermo
authors.initials: G
authors.lastname: Schmeda-Hirschmann
authors.forename: María R
authors.initials: MR
authors.lastname: Alberto
mesh_terms: D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D016718:Arachidonic Acid / Q000378:metabolism; D001118:Argentina; D019659:Asteraceae; D052160:Benzothiazoles / Q000378:metabolism; D051545:Cyclooxygenase 1 / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000378:metabolism; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D007501:Iron / Q000378:metabolism; D008084:Lipoxygenase / Q000378:metabolism; D016859:Lipoxygenase Inhibitors / Q000494:pharmacology*; D008519:Medicine, Traditional; D064801:Phospholipase A2 Inhibitors / Q000494:pharmacology*; D054467:Phospholipases A2 / Q000378:metabolism; D035261:Plant Components, Aerial; D010936:Plant Extracts / Q000494:pharmacology*; D013451:Sulfonic Acids / Q000378:metabolism
chemical_list: D000893:Anti-Inflammatory Agents; D052160:Benzothiazoles; D016861:Cyclooxygenase Inhibitors; D016859:Lipoxygenase Inhibitors; D064801:Phospholipase A2 Inhibitors; D010936:Plant Extracts; D013451:Sulfonic Acids; D016718:Arachidonic Acid; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D007501:Iron; D008084:Lipoxygenase; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D054467:Phospholipases A2