In vitro Inhibitory Effect of Lanostane Triterpenoids of Kadsura coccinea on the Human Immunodeficiency Virus Type-1 Protease

Human immunodeficiency virus type-1 is the causative pathogen of acquired immunodeficiency syndrome and its protease is one of the primary targets for human immunodeficiency virus/acquired immune deficiency syndrome therapy. In this study, two seco-lanostane triterpenoids, 3,4-seco-9βH-lanost-4(28),7,24-trien-3-oic acid and 24(E)-3,4-seco-9βH-lanost-4(28),7,24-trien-3,26-dioic acid isolated from the roots of Kadsura coccinea, were found to significantly inhibit human immunodeficiency virus-1 protease, with IC50 values of 1.0±0.03 µM and 0.05±0.009 µM, respectively. Neither compound was toxic to human embryonic kidney 293T cells at concentrations effective against human immunodeficiency virus-1 protease. Our findings indicate that these triterpenoids are potential candidates for development of antihuman immunodeficiency virus/acquired immune deficiency syndrome drugs.