| Autor: |
Hour MJ; School of Pharmacy, China Medical University, Taichung 40402, Taiwan., Chen Y; Institute of New Drug Development, China Medical University, Taichung 40402, Taiwan., Lin CS; Division of Gastroenterology, Kuang Tien General Hospital, No. 117 Shatian Road, Shalu District, Taichung 43303, Taiwan., Baltina LA; Ufa Institute of Chemistry, Ufa Federal Research Centre of RAS, 71 Prospect Oktyabrya, 450054 Ufa, Russia., Kan JY; Graduate Institute of Biomedical Sciences, China Medical University, 91, Hsueh-Shin Road, Taichung 40402, Taiwan., Tsai YT; Department of Medical Laboratory Science and Biotechnology, China Medical University, 91 Hsueh-Shih Road, Taichung 40402, Taiwan.; Department of Medical Laboratory Science and Biotechnology, Asia University, 500 Lioufeng Road, Wufeng, Taichung 41354, Taiwan., Kiu YT; Department of Medical Laboratory Science and Biotechnology, China Medical University, 91 Hsueh-Shih Road, Taichung 40402, Taiwan., Lai HC; School of Chinese Medicine, China Medical University, 91 Hsueh-Shih Road, Taichung 40402, Taiwan., Baltina LA; Ufa Institute of Chemistry, Ufa Federal Research Centre of RAS, 71 Prospect Oktyabrya, 450054 Ufa, Russia., Petrova SF; Ufa Institute of Chemistry, Ufa Federal Research Centre of RAS, 71 Prospect Oktyabrya, 450054 Ufa, Russia., Lin CW; Graduate Institute of Biomedical Sciences, China Medical University, 91, Hsueh-Shin Road, Taichung 40402, Taiwan.; Department of Medical Laboratory Science and Biotechnology, China Medical University, 91 Hsueh-Shih Road, Taichung 40402, Taiwan.; Department of Medical Laboratory Science and Biotechnology, Asia University, 500 Lioufeng Road, Wufeng, Taichung 41354, Taiwan. |
| Abstrakt: |
Dengue virus (DENV) is one of the most geographically distributed mosquito-borne flaviviruses, like Japanese encephalitis virus (JEV), and Zika virus (ZIKV). In this study, a library of the known and novel Glycyrrhizic acid (GL) derivatives bearing amino acid residues or their methyl/ethyl esters in the carbohydrate part were synthesized and studied as DENV inhibitors in vitro using the cytopathic effect (CPE), viral infectivity and virus yield assays with DENV1 and DENV-2 in Vero E6 and A549 cells. Among the GL conjugates tested, compound hits GL-D-ValOMe 3, GL-TyrOMe 6, GL-PheOEt 11, and GL-LysOMe 21 were discovered to have better antiviral activity than GL, with IC50 values ranging from <0.1 to 5.98 μM on the in vitro infectivity of DENV1 and DENV2 in Vero E6 and A549 cells. Compound hits 3, 6, 11, and 21 had a concentration-dependent inhibition on the virus yield in Vero E6, in which GL-D-ValOMe 3 and GL-PheOEt 11 were the most active inhibitors of DENV2 yield. Meanwhile, the time-of-addition assay indicated that conjugates GL-D-ValOMe 3 and GL-PheOEt 11 exhibited a substantial decrease in the DENV2 attachment stage. Subsequently, chimeric single-round infectious particles (SRIPs) of DENV2 C-prM-E protein/JEV replicon and DENV2 prM-E/ZIKV replicon were utilized for the DENV envelope I protein-mediated attachment assay. GL conjugates 3 and 11 significantly reduced the attachment of chimeric DENV2 C-prM-E/JEV and DENV2 prM-E/ZIKV SRIPs onto Vero E6 cells in a concentration-dependent manner but did not impede the attachment of wild-type JEV CprME/JEV and ZIKV prM-E/ZIKV SRIPs, indicating the inhibition of Compounds 3 and 11 on DENV2 E-mediated attachment. Molecular docking data revealed that Compounds 3 and 11 have hydrophobic interactions within a hydrophobic pocket among the interfaces of Domains I, II, and the stem region of the DENV2 envelope (E) protein. These results displayed that Compounds 3 and 11 were the lead compounds targeting the DENV E protein. Altogether, our findings provide new insights into the structure−activity relationship of GL derivatives conjugated with amino acid residues and can be the new fundamental basis for the search and development of novel flavivirus inhibitors based on natural compounds. |
