Isoginkgetin is a biflavonoid that has been found in G. biloba and is an inhibitor of pre-mRNA splicing. Isoginkgetin (33 μM) reduces the activity of an mRNA-dependent luciferase reporter by 5-fold, shifts the composition of total RNA extract from predominantly mRNA to pre-mRNA, and arrests cell growth in HEK293 cells. Isoginkgetin (10 μM) suppresses mouse lymphocyte proliferation induced by concanavalin A (Con A; ) and LPS by approximately 87 and 90%, respectively. It also suppresses arachidonic acid release induced by phorbol 12-myristate 13-acetate (PMA; ) and the calcium ionophore A23187 by 32.5 and 48.4%, respectively, in rat peritoneal macrophages when used at a concentration of 10 μM. Isoginkgetin (5-20 μM) reduces matrix metalloproteinase-9 (MMP-9) activity, expression, and mRNA levels in and decreases cell invasion by HT1080 fibrosarcoma cells in a concentration-dependent manner.
