Identification of the anti-fungal drug fenticonazole nitrate as a novel PPARγ-modulating ligand with good therapeutic index: Structure-based screening and biological validation

In this study, SB-VHTS of the old drug library was conducted to seek for novel PPARγ ligand. In the end, an antifungal drug, FN, was identified in vitro and in vivo as a new and potent PPARγ-modulating ligand to demonstrate significantly anti-diabetic and anti-NAFLD efficacies with minimized side effects induced by PPARγ full agonists TZDs drugs. Further mechanistic investigations revealed that FN showed such desired pharmacological properties mainly through selectively activating the expressions of Adiponectin and GLUT4, effectively promoting the Akt Ser473 phosphorylation, inhibiting the expressions of proinflammatory genes including TNF-α, IL-1β and IL-6 and blocking the PPARγ Ser273 phosphorylation mediated by CDK5 without leading to adipogenesis and increasing the expressions of key adipogenic genes CD36, AP2, LPL, C/EBPα, FASN and PPARγ. Subsequently, a molecular docking study revealed an interesting binding mode between FN and PPARγ LBD including the hydrogen-bonding network among oxygen atom, sulfur atom and nitrogen atom in FN respectively with the PPARγ residues Cys285, Tyr327 and Ser342, which gave proof of concept for the above anti-diabetic action mechanism. Taken together, our findings not only suggest that FN can serve as the new, safe and highly efficacious anti-diabetic and anti-NAFLD agents for clinical use, they can also provide a molecular basis for the future development of PPARγ modulators with a high therapeutic index and the possibility to explore new uses of old drugs for immediate drug discovery.