Planta Med 2003; 69(8): 765-767
DOI: 10.1055/s-2003-42795
Letter
© Georg Thieme Verlag Stuttgart · New York

Dual Effect of Saikogenin D: In vitro Inhibition of Prostaglandin E2 Production and Elevation of Intracellular Free Ca2+ Concentration in C6 Rat Glioma Cells

Yasuo Kodama1 , Lv Xiaochuan2 , Chikako Tsuchiya2 , Yasushi Ohizumi1 , Makoto Yoshida2 , Norimichi Nakahata2
  • 1Department of Pharmaceutical Molecular Biology, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba, Aramaki, Aoba-ku, Sendai, Japan
  • 2Department of Cellular Signaling, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba, Aramaki, Aoba-ku, Sendai 980-8578, Japan
This work was partially supported by the grant-in-aid for Scientific Research (No. 14 572 049 to M.Y.; No. 14 370 737 to N.N.) from the Ministry of Education, Culture, Science, Sports and Technology of Japan, and by the grant-in-aid for special researcher (to L.X.) from Sasagawa Foundation
Further Information

Publication History

Received: November 21, 2002

Accepted: April 26, 2003

Publication Date:
06 October 2003 (online)

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 μM) inhibited PGE2 production induced by the Ca2+ ionophore A23187 in a concentration-dependent manner with the IC50 of about 3 μM. 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 μM) with the EC50 value of about 35 μM 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.

References

Norimichi Nakahata

Department of Cellular Signaling

Graduate School of Pharmaceutical Sciences

Tohoku University

Aoba

Aramaki

Aoba-ku

Sendai 980-8578

Japan

Phone: +81-22-217-6809

Fax: +81-22-217-6809

Email: nakahata@mail.pharm.tohoku.ac.jp