title: Imbricaric acid and perlatolic acid: multi-targeting anti-inflammatory depsides from Cetrelia monachorum.
abstract: In vitro screening of 17 Alpine lichen species for their inhibitory activity against 5-lipoxygenase, microsomal prostaglandin E2 synthase-1 and nuclear factor kappa B revealed Cetrelia monachorum (Zahlbr.) W.L. Culb. & C.F. Culb. As conceivable source for novel anti-inflammatory compounds. Phytochemical investigation of the ethanolic crude extract resulted in the isolation and identification of 11 constituents, belonging to depsides and derivatives of orsellinic acid, olivetolic acid and olivetol. The two depsides imbricaric acid (4) and perlatolic acid (5) approved dual inhibitory activities on microsomal prostaglandin E2 synthase-1 (IC50 = 1.9 and 0.4 µM, resp.) and on 5-lipoxygenase tested in a cell-based assay (IC50 = 5.3 and 1.8 µM, resp.) and on purified enzyme (IC50 = 3.5 and 0.4 µM, resp.). Additionally, these two main constituents quantified in the extract with 15.22% (4) and 9.10% (5) showed significant inhibition of tumor necrosis factor alpha-induced nuclear factor kappa B activation in luciferase reporter cells with IC50 values of 2.0 and 7.0 µM, respectively. In a murine in vivo model of inflammation, 5 impaired the inflammatory, thioglycollate-induced recruitment of leukocytes to the peritoneum. The potent inhibitory effects on the three identified targets attest 4 and 5 a pronounced multi-target anti-inflammatory profile which warrants further investigation on their pharmacokinetics and in vivo efficacy.
authors.affiliation: Institute of Pharmacy/Pharmacognosy, Center for Molecular Biosciences Innsbruck, Leopold-Franzens University of Innsbruck, Innsbruck, Austria.
authors.forename: Sarah K
authors.initials: SK
authors.lastname: Oettl
authors.forename: Jana
authors.initials: J
authors.lastname: Gerstmeier
authors.forename: Shafaat Y
authors.initials: SY
authors.lastname: Khan
authors.forename: Katja
authors.initials: K
authors.lastname: Wiechmann
authors.forename: Julia
authors.initials: J
authors.lastname: Bauer
authors.forename: Atanas G
authors.initials: AG
authors.lastname: Atanasov
authors.forename: Clemens
authors.initials: C
authors.lastname: Malainer
authors.forename: Ezzat M
authors.initials: EM
authors.lastname: Awad
authors.forename: Pavel
authors.initials: P
authors.lastname: Uhrin
authors.forename: Elke H
authors.initials: EH
authors.lastname: Heiss
authors.forename: Birgit
authors.initials: B
authors.lastname: Waltenberger
authors.forename: Daniel
authors.initials: D
authors.lastname: Remias
authors.forename: Johannes M
authors.initials: JM
authors.lastname: Breuss
authors.forename: Joel
authors.initials: J
authors.lastname: Boustie
authors.forename: Verena M
authors.initials: VM
authors.lastname: Dirsch
authors.forename: Hermann
authors.initials: H
authors.lastname: Stuppner
authors.forename: Oliver
authors.initials: O
authors.lastname: Werz
authors.forename: Judith M
authors.initials: JM
authors.lastname: Rollinger
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000302:isolation & purification / Q000494:pharmacology*; D001203:Ascomycota / Q000737:chemistry*; D001565:Benzoates / Q000302:isolation & purification / Q000494:pharmacology*; D053630:Depsides / Q000302:isolation & purification / Q000494:pharmacology*; D004353:Drug Evaluation, Preclinical; D057809:HEK293 Cells; D006801:Humans; D020128:Inhibitory Concentration 50; D007962:Leukocytes / Q000187:drug effects / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010537:Peritoneum / Q000187:drug effects / Q000276:immunology
chemical_list: D000893:Anti-Inflammatory Agents; D001565:Benzoates; D053630:Depsides; C000588767:imbricaric acid; C522034:perlatolic acid