Inhibitory Effect of Sulfated Chitooligosaccharides on HIV-1 Infection

Abstract

Human immunodeficiency virus type-1 (HIV-1) is identified as the causative agent of acquired immunodeficiency syndrome (AIDS) which is one of the most important diseases with about 33.2 million people infected worldwide. Recently, it has been crucial to identify compounds with less or no cytotoxicity and higher inhibitory activity against various HIV strains, including the ones which are resistant to drugs currently used for antiretroviral therapy. Despite the advances in rational drug design, natural products stand as the most important drug candidates for the inhibition of HIV infection. In the present study, in vitro anti-HIV properties of various molecular weight sulfated chitooligosaccharides (SCOSs) were investigated. According to the results obtained from the experiments, SCOSs inhibited the replication of HIV-1, as well as protected T-lymphoblasts from HIV-1 induced cytopathic effects and almost completely reduced cell culture HIV-1 p24 antigen level. The delayed addition analysis of SCOSs in co-culture studies revealed that SCOS’s action was at the early stage of HIV-1 replication. SCOSs blocked not only cell-to-cell fusion process of HIV infected and uninfected cells, but also cell free virus attachment. SCOSs with different molecular weight also exhibited different inhibitory patterns. These results indicate that SCOSs are potentially safe HIV-1 inhibitors with high activity at non-cytotoxic concentrations.