School of Chinese Medicine
Saikosaponin-d inhibits T cell activation through the modulation of PKCθ, JNK and NF-κB transcription factor
The effects of saikosaponin-d, a triterpene saponin derived from Bupleurum falcatum L. (Umbelliferae), on the signaling pathways of T cell activation were examined. The results showed that saikosaponin-d potently suppressed both early (CD69) and late (CD71) expressions of mouse T cells stimulated with Con A or PMA. It interfered with PKCθ translocation from cytosol to membrane fraction and inhibited the phosphorylations of IκBα and JNK, but not ERK, in PMA-activated mouse T cells. Additionally, it inhibited PMA and ionomycin-stimulated IL-2 production in mouse T cells. In summary, these results indicate that the mechanism by which saikosaponin-d inhibits T cell activation would involve the suppression of CD69 and CD71 expressions and IL-2 production, and the modulation of PKC pathway through PKCθ, JNK, and NF-κB transcription factor. This may herald a novel approach for further studies of saikosaponin-d as a candidate for use in the treatment of inflammatory and autoimmune diseases. © 2005 Elsevier Inc. All rights reserved.
CD69, CD71, ERK, IκBα, JNK, PKCθ, Saikosaponin-d, Signal transduction, T cell activation
Source Publication Title
Biochemical and Biophysical Research Communications
Link to Publisher's Edition
Leung, Chung Yee, Liang Liu, Ricky N.S. Wong, Yao Ying Zeng, Ming Li, and Hua Zhou. "Saikosaponin-d inhibits T cell activation through the modulation of PKCθ, JNK and NF-κB transcription factor." Biochemical and Biophysical Research Communications 338.4 (2005): 1920-1927.