Background: The kidneys are a potential target for SARS-CoV-2 infection. Ascorbic acid (vitamin C) has been shown to play an important role in reducing the symptoms of SARS-CoV-2. Recently liposomal drug delivery platforms have demonstrated promising results in enhancing the effectiveness of various therapeutics including infectious diseases. In this study, we designed a liposomal delivery system containing vitamin C to evaluate its antiviral efficacy in COVID-19, focusing on its effects on viral entry gene expression in Vero cells.
Methods: Vitamin C was loaded into a liposome made up of hydrogenated soybean phosphatidylcholine, cholesterol, and 1,2-distearoyl-sn-glycero-3 phosphoethanolamine-N-[methoxy (polyethylene glycol)-2000], and their physicochemical properties were assessed. Next, the cytotoxicity of free and liposomal vitamin C on the survival of the Vero cell line was evaluated using the MTT assay. In addition, the expression of viral entry genes, angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2), key mediators of SARS-CoV-2 entry into kidney cells, was investigated using RTq-PCR.
Results: Liposomes were successfully loaded with vitamin C, achieving an encapsulation efficiency of 88.03%. The liposomal vitamin C formulation exhibited a brilliant surface morphology as observed by SEM. Both free and liposomal forms of vitamin C showed cytotoxic effects at higher concentrations. Moreover, both forms downregulated the expression of viral entry genes, although the liposomal form showed superior inhibitory performance compared to the free form.
Conclusions: The study suggests liposomal vitamin C as a safe, effective treatment for COVID-19 by targeting viral entry genes in kidney cells, protecting them from viral damage and inflammation.
Keywords: Ascorbic Acid; COVID-19; Liposomes; Renal Cells; Viral Entry.