Anti-HIV-1 Activities of Hemslecins A and B

ABSTRACTAIMTo study anti-HIV-1 activities of two triterpenoids, hemslecins A and B from a Chinese medicinal plant Hemsleya jinfushanensis.METHODSThe cellular inhibitory assays on syncytia formation induced by HIV-1, p24 antigen production in HIV-1 acutely infected C8166 cells, cell-to-cell fusion between HIV-1 chronically infected H9 cells and normal C8166 cells, and p24 production from HIV-1 chronically infected H9 cells were assayed. The effects on NCp7 zinc ejection and inhibitory activities against HIV-1 reverse transcriptase (RT) and protease (PR) were also detected.RESULTSThe hemslecins A and B with inhibitory effects on (1) syncytia formation induced by HIV-1 with EC50 values of 3.09 and 2.53 μg·mL−1 respectively, (2) p24 antigen production in HIV-1 acutely infected C8166 cells with EC50 of 3.97 and 18.90 μg·mL−1 respectively, and (3) fusion between HIV-1 chronically infected H9 cells and C8166 cells with EC50 of 1.76 μg·mL−1 and 11.95 μg·mL−1, respectively. But hemslecins A and B failed to show inhibitory activity against HIV-1 RT, PR, and NCp7 zinc ejection. Hemslecin A not hemslecin B showed slight interaction with HIV-1 integrase. In co-culture assay, hemslecins A and B showed more effect in pretreated C8166 cells group than no pretreated group.CONCLUSIONThe hemslecins A and B are bioactive compounds against HIV-1 and their action mechanism might be correlated with virus entry.