Novel Antiviral Investigation of Annona squamosa Leaf Extract against the Dengue Virus Type-2: In vitro Study

Introduction: Dengue virus (DENV) infection is general mosquito-transmitted viral taint. It can lead to the dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS). Dengue is a solemn illness with no endowed antiviral medication or recognized vaccine. Therefore, we aimed to investigate the activity of Annona squamosa leaf extract (ASLE) against dengue virus type-2 (DENV-2) isolated from Surabaya, Indonesia in 2013 (NCBI accession number: KT012509). Methods: In this study, the antiviral activity of ASLE was evaluated against DENV- 2 in Vero cells using Viral ToxGlo™ Assay. In addition, we used CellTiter-Glo^® Luminescent Cell Viability Assay to set the amount of viable cells in culture based on quantitation of the ATP. Results: DENV-2 replication inhibited by ASLE in Vero cells with IC₅₀ = 73.78 μg/mL and SI = 4.49 when cells were treated two days after virus infection, whereas its CC₅₀ for cytotoxicity to Vero cells was 331.54 μg/mL. Interestingly, this is the first report on the investigation of ASLE against DENV-2. Conclusion: In summary, ASLE demonstrated the antiviral activity against DENV-2 with less toxicity, and high possibility as a drug candidate. Therefore, it might be suggested for in vivo assessment in the progress of a potent antiviral against DENV-2.