Effect of curcumin on LPS-induced neutrophil activation and acute lung injury

Abstract

Curcumin has antioxidant, antitumor, and anti-inflammatory properties. Neutrophils play an important role in the development of organ dysfunction associated with severe infection. This study was performed to evaluate the effects of curcumin on lipopolysaccharide (LPS) - induced neutrophil activation and acute lung injury.

To assess the anti-inflammatory effect of curcumin on LPS induced neutrophil activation, neutrophils from human blood were incubated with various concentrations of curcumin (0, 1, 10, 50 and 100 nM) and LPS (100 ng/ml). The protein levels for interleukin (IL)-6, 8 and tumor necrosis factor (TNF)-α were measured using ELISA 4 hr after incubation period. To elucidate the intracellular signaling pathway, We measured the levels of phosphorylation of p38 mitogen activated protein kinases (p38), extracelluar signal-regulated kinase (ERK)1/2 and c-Jun amino-terminal kinases (JNK) with western blot analysis and nuclear levels of nuclear factor (NF)-κB with electrophoretic mobility shift assays 0.5 hr after incubation period. We also examined the effect of curcumin (60mg/kg, IP) on acute lung injury and mortality of mouse treated with LPS(20 mg/kg, IP) to determine whether these effects of curcumin also have in vivo significance.

Curcumin attenuated LPS - induced neutrophils activation including expression of p38, JNK, NF-κB, IL-6, 8 and TNF-α. Mouse treated by Curcumin were protected from LPS-induced lung injury, as determined by wet/dry weight ratio, lung injury score and IL-6, 8 and TNF-α in bronchoalveolar lavage fluid (BALF) levels and mortality.Curcumin can attenuate LPS - induced acute lung injury and mortality via the attenuation of neutrophil activation caused by LPS.