Picroside I (6'-Cinnamoylcatalpol), a hepatoprotective agent, is reported to be antimicrobial and used against hepatitis B. It has antioxidant, and anti-inflammatory activities, it may be the valuable anti-invasive drug candidates for cancer therapy by suppressing Collagenases and Gelatinases. Picroside I can enhance basic fibroblast growth factor(bFGF)-, staurosporine- or dbc-mitogen-activated protein (MAP)-induced neurite outgrowth from PC12D cells.

Picroside I and Picroside II caused a concentration-dependent (> 0.1 microM) enhancement of basic fibroblast growth factor (bFGF, 2 ng/ml)-, staurosporine (10 nM)- and dibutyryl cyclic AMP (dbcAMP, 0.3 mM)-induced neurite outgrowth from PC12D cells. Furthermore, picrosides-induced enhancements of the bFGF-action were markedly inhibited by GF109203X (0.1 microM), a protein kinase C inhibitor. The expression of phosphorylated MAP kinase was markedly increased by bFGF (2 ng/ml) and dbcAMP (0.3 mM), whereas that was not enhanced by staurosporine (10 nM). Picrosides had no effect on the phosphorylation of MAP kinase induced by bFGF or dbcAMP and also unaffected it in the presence of staurosporine. These results suggest that Picroside I and Picroside II enhance bFGF-, staurosporine- or dbcAMP-induced neurite outgrowth from PC12D cells, probably by amplifying a down-stream step of MAP kinase in the intracellular MAP kinase-dependent signaling pathway.