Abstract: To screen class Ⅰ HDAC inhibitors of natural origin,in total 60 compounds from traditional Chinese medicine were evaluated the HDAC inhibitory effect by employment of HDAC inhibitor screening kits.Compounds exhibiting higher activity to inhibit HDAC were further investigated the effect on inhibiting HDAC3/8 activity by using HDAC3/8 inhibitor screening kits,and the effect on protein expression of class Ⅰ HDACs in HeLa cells by Western-blotting.It was found that,Sanguinarine，Piperine,Isoliquiritigenin,Isoliquiritin,Salvianolic acid C were more active than others to inhibit HDAC activity;Isoliquiritigenin and Isoliquiritin significantly inhibited HDAC3/8 activity;In addition,Sanguinarine strongly inhibited cell proliferation and cellular expression of class Ⅰ HDACs in HeLa cells.Our results showed that Isoliquiritigenin,Isoliquiritin and Sanguinarine are potential inhibitors of class Ⅰ HDACs.Among them Sanguinarine is worth further studying.

Key words: screening of ClassⅠHDAC inhibitors, natural compounds, sanguinarine, isoliquiritigenin, isoliquiritin