Inhibition of acute lung injury by rubriflordilactone in LPS-induced rat model through suppression of inflammatory factor expression

The present study demonstrates the effect of rubriflordilactone on lipopolysaccharide (LPS)-induced acute kidney injury in rats and MLE-15 cells. LPS administration in rats resulted in formation of edema which was inhibited by pretreatment with rubriflordilactone. The pulmonary tissues of LPS administered rats and MLE-15 cells showed a significant increase in the expression of matrix metalloproteinase-9, interleukin-6 and inducible nitric oxide synthase. However, rubriflordilactone treatment prior to LPS administration caused a significant reduction in the expression of these factors at a concentration of 10 nm/kg. Analysis of the Sirtuin 1 (Sirt1) expression revealed significant (P=0.002) reduction on exposure to LPS in MLE-15 cells. However, rubriflordilactone treatment at 10 nm/ml concentration before LPS exposure caused inhibition of LPS induced reduction in Sirt1 expression. Silencing of Sirt1 by siRNA in MLE-15 cells led to inhibition of increased Sirt1 expression by rubriflordilactone in LPS administered rats. These findings suggest that rubriflordilactone inhibits LPS induced acute lung injury in rats and MLE-15 cells through promotion of Sirt1 expression.