title: In vitro inhibitory effects of thymol and quinones of Nigella sativa seeds on cyclooxygenase-1- and -2-catalyzed prostaglandin E2 biosyntheses.
abstract: Dithymoquinone, thymohydroquinone, thymol and thymoquinone, compounds derived from N. sativa seeds, were investigated for their in vitro anti-inflammatory activities using cyclooxygenase-1 (COX-1) and -2 (COX-2) assays. Our results show that all substances tested possess significant inhibitory activity against at least one COX form at concentrations comparable to the active one of indomethacin. Thymol was the most active against COX-1 with an IC (50) value of 0.2 microM while thymohydroquinone and thymoquinone exhibited the strongest inhibitory effect on COX-2 with IC (50) values of 0.1 and 0.3 microM, respectively. Moreover, dithymoquinone and thymoquinone showed a limited COX-2-specific inhibition. We conclude that dithymoquinone, thymohydroquinone, thymol and thymoquinone can participate in the general anti-inflammatory activity of N. sativa and suggest that these agents should be further studied for possible use as non-steroidal anti-inflammatory drugs.
authors.affiliation: Department of Plant Tissue Cultures, Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Marsik
authors.forename: Ladislav
authors.initials: L
authors.lastname: Kokoska
authors.forename: Premysl
authors.initials: P
authors.lastname: Landa
authors.forename: Ales
authors.initials: A
authors.lastname: Nepovim
authors.forename: Petr
authors.initials: P
authors.lastname: Soudek
authors.forename: Tomas
authors.initials: T
authors.lastname: Vanek
mesh_terms: D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D015232:Dinoprostone / Q000096:biosynthesis*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D020128:Inhibitory Concentration 50; D008565:Membrane Proteins; D031881:Nigella sativa; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism*; D011809:Quinones / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D012639:Seeds; D013943:Thymol / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors; D008565:Membrane Proteins; D010936:Plant Extracts; D011809:Quinones; D013943:Thymol; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; C496511:PTGS1 protein, human; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D015232:Dinoprostone