Protective effect of curcumin on acute lung injury induced by lipopolysaccharide in mice

GU Zhi-long; JIANG Hua-mao; HU Zhan-sheng

doi:10.3969/j.issn.1002-266X.2015.22.002

Abstract：Objective To observe the protective effect of curcumin on acute lung injury ( ALI) induced by lipopo-lysaccharide ( LPS) in mice and to investigate the mechanism.Methods Sixty BALB/C male mice in SPF grade were randomly divided into groups A, B, C, D, E and F, 10 mice in each group.Mice in the groups A, B and C were daily in-jected with 4 mL normal saline intraperitoneally, once a day and for 7 d;after that, on day 8, mice in the group B were ad-ministered with 5 mg/kg LPS for once, and each mouse in the group C was injected with 50 μg TLR-4/MD antibodies 10-12 h before being administered with 5 mg/kg LPS.In the group A, on day 8, the lung tissues and peripheral blood were obtained and in groups B-F, the lung tissues and peripheral blood were obtained 4-6 h after intraperitoneal injection of LPS under the sterile conditions.The peripheral blood plasma was separated to detect the plasma LPS levels.The lung tissue specimen in each group received HE staining, then we observed the pathology changes of the lung tissues.The TLR4 mR-NA expression in the lung tissues of each group was detected by RT-PCR, and the TLR4 protein expression in the lung tis-sues of each group was detected by Western blotting.The specimens of lung tissues received immunohistochemical staining, and then we detected the expression of MyD88 and NF-κB.Results Compared with group A, the plasma LPS was in-creased (P<0.01), lung tissue showed ALI, and TLR4 mRNA and protein expression, MyD88 and NF-κB expression was up-regulated in the group B (all P<0.01).Compared with group B, the plasma LPS was significantly decreased (all P<0.01), the pathology damage of lung tissues declined, TLR4 mRNA and protein expression was down-regulated (all P<0.01), MyD88 and NF-κB expression was down-regulated in the groups D, E and F (all P<0.01).Conclusion Curcu-min has a protective effect on ALI induced by LPS in mice.The mechanism may be related to the inhibition of LPS-TLR4 combination and the activation of MyD88-Nf-kB signal pathway.