Effect of Curcumin on protection of organ function and serum levels of IL-18 in LPS-induced sepsis in rats

Objective To investigate the protective mechanisms of Curcumin on organ injury caused by LPS-induced sepsis in rats.Methods Sixty Wister male rats were randomly divided into three groups: the control group(C group,n=12),the LPS-induced sepsis group(LPS group,n=24),the Curcumin treatment group(LPS+Cur group,n=24).Sepsis was induced by intraperitoneal injection of 5 mg/kg LPS.The LPS+Cur group was injected with 50 mg/kg curcumin,immediately followed by intraperitoneal LPS injection.At 4,8,12 and 24 h after the start of experiment,blood was obtained from the inferior vena cava of rats and serum ALT,AST,Cre,BUN,IL-18 and TNF-αwere measured.Then these rats were killed by cervical dislocation at each time point and their liver and kidney tissues were kept for histological examination.Results Compared with the C group,ALT,AST,Cre and BUN levels of the LPS group were significantly increased at each time point(P0.01) and peaked at 8 h;IL-18 and TNF-α levels of the LPS group were significantly increased at 4,8,12 h(P0.01) and both peaked at 8 h while no significance was obsertved at 24 h(P0.05).Compared with the LPS group,ALT,AST,Cre,BUN,IL-18 levels of the LPS+Cur group were significantly decreased at each time point(P0.05);TNF-α levels of the LPS+Cur group were significantly decreased at 4,8,12 h(P0.05) while no significance was observed at 24 h(P0.05).Pathological changes in liver tissues of the LPS group were mainly diffuse vacuolar degeneration,scattered eosinophilic degeneration,scattered acute and chronic inflammatory cells infiltration of hepatic sinusoids,focal necrosis of liver cells,small abscess formation.Pathological changes in kidney tissues were mainly diffuse infiltration of neutrophils in glomerular,part of segmental glomerular necrosis,balloon dilatation,diffuse tubular brush border loss,part of the tube formation,local severe vacuolar degeneration.Pathological changes in liver and kidney tissues were the severest at 8 h,which was in agreement with serum biochemical and immune parameters.Pathological changes in liver and kidney tissues of the LPS+Cur group were significantly ameliorated when compared with the LPS group.Conclusions Sepsis can cause acute liver and kidney damage.IL-18 can be used to determine organ damage caused by sepsis as a detection marker.Curcumin can protect organ function from injury caused by sepsis because it can inhibit excessive production of TNF-α and IL-18 and reduce the excessive inflammatory response in sepsis.