Identification of effective synthetic molecules against viral-induced cytokine release syndrome using in silico and in vitro approaches.

Acute respiratory distress syndrome (ARDS) is the leading cause of mortality in pathogen-mediated lung inflammation. Viral-induced cytokine release syndrome (CRS) has emerged as a global pandemic, characterized by a hyperactive immune response and excessive cytokine production causing irreversible lung injury. This study aimed to evaluate FDA-approved drugs for their potential to target hyperactive immune response and SARS-CoV-2 viral replication simultaneously. Six potential 3-CLpro inhibitors were identified by molecular docking using MOE software, including ebastine (1), orlistat (2), atracurium besylate (3), piperaquine phosphate (4), valsartan (5), and acarbose (6), among which 1-3 binds strongly to the target protein with binding affinity of - 8.22, - 9.12, and - 7.81, kcal/mol, respectively. Additionally, all identified inhibitors except 4 revealed significant anti-viral potential, with a 50-100% reduction in SARS-CoV-2 plaques. Significant attenuation of phagocyte oxidative burst and inflammatory cytokines (IFN-γ, GM-CSF, IL-6, IL-2, IL-1β, TNF-α) demonstrated the immunomodulatory potential of these drugs. This study demonstrates the potential of pre-existing drugs to ameliorate the cytokine storm and oxidative damage with simultaneous anti-viral effects. The data provide pre-clinical support to develop these drugs as potential therapeutic agent against ARDS.