摘要
The limited treatment options for the increasing occurrence of Lassa hemorrhagic fever in West Africa poses an urgent need for the discovery and development of novel therapeutics.Dietary supplements,especially natural products that are edible and safe for human use,are a good source of drug discovery with potential for uncovering novel applications,In this study,we tested 40 natural products of dietary supplements and identified capsaicin,a common dietary supplement abundant in chili peppers,as an inhibitor of Lassa virus(LASV)entry with EC5,of 6.9-10.0μmol/L using an HIV based pseudo virus platform.Capsaicin inhibits the entry of five LASV strains but not against the Old World arenavirus lymphocytic choriomeningitis virus(LCMV),showing a preferential activity against LASV.Capsaicin inhibits LASV entry by blocking the pH dependent viral fusion through affecting the stable signal peptide(SSP)-GP2 transmembrane(GP2TM)region of the LASV surface glycoprotein.Mutational study revealed the key residues Ala25,Val431,Phe434 and Val435 in SsP-CP2TM region in capsaicin’s antiviral effect.This study for the first time reveals a direct acting antiviral effect of capsaicin against the hemorrhagic fever causing LASV,providing detailed interaction hot spots in the unique SSP-GP2TMinterface of LASV glycoprotein that is crucial in fusion inhibition,and offering a new strategy in discovering and developing antivirals from natural products that are safe for human use.
基金
financially supported by the National Natural Science Foundation of China(Nos.81473256 and 81273561)
the CAMS Innovation Fund for Medical Sciences(No.2016-I2M-1014,China)
the Science and Technology Program of Beijing(No.Z151100000115008,China)
the Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study(No.BZ0150,China)
the Drug Innovation Major Project(Nos.2015ZX09102-023 and 2018ZX09711001-003-002,China)
the Disciplines Construction Project(No.201920200802,China)