title: Dual effect of saikogenin D: in vitro inhibition of prostaglandin E2 production and elevation of intracellular free Ca2+ concentration in C6 rat glioma cells.
abstract: To clarify the pharmacological profile of saikogenin D, we examined the effect of saikogenin D on prostaglandin E2 (PGE2) production and intracellular free Ca2+ concentration ([Ca2+]i) in C6 rat glioma cells. Saikogenin D (1-20 microM) inhibited PGE2 production induced by the Ca2+ ionophore A23187 in a concentration-dependent manner with the IC50 of about 3 microM. Saikogenin D did not affect the conversion of arachidonic acid into PGE2 in microsomal preparations. On the other hand, saikogenin D elevated [Ca2+]i in a concentration-dependent manner (10-100 microM) with the EC50 value of about 35 microM in the presence or absence of extracellular Ca2+. These results suggest that saikogenin D possesses a dual effect: an inhibition of A23187-induced PGE2 production without a direct inhibition of cyclooxygenase activity; and an elevation of [Ca2+]i that is attributed to Ca2+ release from intracellular stores.
authors.affiliation: Department of Pharmaceutical Molecular Biology, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba, Aramaki, Aoba-ku, Sendai, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Kodama
authors.forename: Lv
authors.initials: L
authors.lastname: Xiaochuan
authors.forename: Chikako
authors.initials: C
authors.lastname: Tsuchiya
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ohizumi
authors.forename: Makoto
authors.initials: M
authors.lastname: Yoshida
authors.forename: Norimichi
authors.initials: N
authors.lastname: Nakahata
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D029972:Bupleurum; D002118:Calcium / Q000378:metabolism*; D045744:Cell Line, Tumor / Q000187:drug effects; D015232:Dinoprostone / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D004305:Dose-Response Relationship, Drug; D005910:Glioma / Q000188:drug therapy / Q000473:pathology; D009828:Oleanolic Acid / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology* / Q000627:therapeutic use; D008517:Phytotherapy; D018517:Plant Roots; D011448:Prostaglandin Antagonists / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D051381:Rats
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D011448:Prostaglandin Antagonists; C009198:saikogenin A; D009828:Oleanolic Acid; D015232:Dinoprostone; D002118:Calcium