Effects Of Chlorogenic Acid Pre-interference On Acute Inflammation Of C57BL/6Mice

Objective:Chlorogenic acid is widely distributed in plants diets, and it’s also to be a main function cotent of some anti-inflammatory herbal ingredients, so we intend to study whether chlorogenic acid intake can prevent acute inflammation. For liver is an important metabolic organ, we studied different doses of chlorogenic acid on serum activity of ALT and AST. Also,we dentect the mRNA expression of TNF-α、IL-1β、 iNOS、COX-2、TLR-4、IKK-β、NF-κB p65and IL-10of mice liver in order to explore the effect of chlorogenic acid on LPS-induced liver injury in mice and its possible mechanism.Methods:Before experiments were performed,40healthy male C57BL/6mice (weight20-23g) were randomly divided into eight groups:group NC mice were given injection with sterile saline;group LM mice were injected intraperitoneally(i.p) with LPS (30mg/kg);groups LA50/100/200mice were administrated orally with different dose of chlorogenic acid (50,100and200mg/kg) before injected with LPS (30mg/kg); groups A50/100/200mice were gavage with different dose of chlorogenic acid (50,100and200mg/kg) before given injection with saline. The group NC and LM mice were administered intragastrically with the same volume water. Before i.p all mice were administrated orally with chlorogenic acid or water for10days. All the gavage and i.p volume were0.1ml per10g of weight. All mice were sacrificed12h after i.p LPS or saline. Mice were allowed free access to drinking water or food. The serum activity of ALT and AST were assayed after all the mice were sacrificed, and the mRNA expression level of TNF-a, IL-1β, iNOS, COX-2and TLR-4, IKK-p, NF-κB p65and IL-10in liver were measured by real-time quantitative PCR. Livers tissue sections were stained with H&E method for normal histological assessment.Result:The study showed that there were no significant effects on serum activity of ALT and AST after administrate with chlorogenic acid(50,100mg/kg)alone. But when intake high dose (200mg/kg), the serum activity of AST and ALT have a non-significantly improved. Macrophage gathering was also found in mice liver administrate with high dose of chlorogenic acid throw the H&E staining. Injected with LPS do really induced liver injury for plasma activity of ALT and AST were remarkably up-regulated, and the mRNA expression level of TNF-α、IL-1β、IL-6、 iNOS and COX-2were all improved. The mRNA expression level of TNF-α、IL-1β、 IL-6、iNOS and COX-2in middle-dose of chlorogenic acid interference mice group were all in the same level compare with the model group, but the expression of anti-inflammation cytokine IL-10were significantly improved. The expression of TNF-α、IL-1β、IL-6、iNOS and COX-2were all significantly improved in high-dose interference group while IL-10was in the same level compare with model group. Conclusion:All together, our data suggested that the appropriate dose of chlorogenic acid do not lead to liver injury, but high dose of chlorogenic acid can lead to some liver injury. Pre-interference with chlorogenic acid could not inhibit inflammation induced by LPS. High-dose (200mg/kg) of chlorogenic acid was likely to made inflammation worse for itself toxicity.