Medicarpin Mediates the Protective Effect of Cell Pyroptosis Against Sepsis-Induced Liver Injury by...

The liver is a decisive organ that is damaged by sepsis. Medicarpin (Med) is a principal wing-type final product of 5-deoxyisoflavone sub-branch in M. truncatula, and exerts anti-tumor and anti-inflammatory effects in diverse diseases. This research aimed to elucidate the Med function and the prospective mechanism in sepsis-induced liver injury. After treating THLE-2 cells with diverse Med concentrations (0, 5, 10, 20, 40, 80, 160 μM), Med toxic effect on THLE-2 cells was checked through a Cell Counting Kit-8 (CCK-8) experiment. Based on a sepsis-induced liver injury model using lipopolysaccharide (LPS) and THLE-2 cells, Med function in sepsis-induced liver injury was verified via CCK-8 assay, Western blot, immunofluorescence, and ELISA. Also, Med mechanism in sepsis-induced liver injury was examined via Western blot, CCK-8 assay, and ELISA. Furthermore, Med role in sepsis-induced liver injury in vivo model was elucidated through animal experiments, hematoxylin-eosin staining, ELISA, Western blot, and immunofluorescence. Med possessed no obvious impact on THLE-2 cell viability when Med concentration was lower than 160 μM. Med alleviated repression of LPS-induced THLE-2 cell viability, and also reduced THLE-2 cell pyroptosis induced by LPS. From a mechanistic perspective, our data further illustrated that LPS induced a decrease in THLE-2 cell viability, and Med enhanced cell viability, while this impact was partially reversed after NLRP3 overexpression, indicating that Med partially counteracted the effects of NLRP3 overexpression on cell viability. Meanwhile, in vivo experimental data further demonstrated that Med alleviated liver injury and pyroptosis in sepsis mice, mainly through reduction of ALT and AST levels, a decrease in liver injury score of mice, a reduction in IL-1β and IL-18 levels, as well as a decrease in NLRP3, ASC, cleaved caspase-1, and GSDMD-N protein levels. In conclusion, Med exerted its protective effect on sepsis-induced liver injury through NLRP3/GSDMD/caspase-1-mediated cell pyroptosis.