Effects of scrocaffeside A from Picrorhiza Scrophulariiflora on immunocyte function in vitro.

Picrorhiza scrophulariiflora is a traditionally used herb for the treatment of various diseases, including tumors and liver infections. In the present report, one glycoside from the methanol extract of Picrorhiza scrophulariiflora, scrocaffeside A, shows immunomodulatory properties by structure. So we measured various indicators of mammalian immune cells to test its immunostimulation potential. The scrocaffeside A enhanced proliferation of splenocytes and their response to polyclonal T cell mitogen concanavalin A (Con A) and lipopolysaccharide (LPS). There was also a significant increase in the activity of peritoneal macrophages and natural killer cell when treated with doses of scrocaffeside A between 5 microg/ml and 125 microg/ml. A dose-dependent increase was also observed in the populations of mature T cell subsets. The production of cytokines and the CD4/CD8 population of splenocytes were also elevated. The levels of interleukin (IL)-2, IL-4, IL-12, and (IFN)-gamma expressed by cultured splenocytes were significantly increased when the cells were exposed to scrocaffeside A. These results indicate that scrocaffeside A may exert immunoenhancement effects on immune system. In addition to its traditional use in some diseases, it may become a new immunostimulating agent in the future.