The Effects Of EGCG On AFB₁ Induced Liver Acute Injury In Rats

ObjectiveEpigallocatechin Gallate?EGCG?is a polyphenolic compound with the highest content and the highest activity in green tea.It has many biological functions,such as antioxidation,anti-inflammation,anti-cancer and so on.Aflatoxin B₁?AFB₁?is a toxin produced by Aspergillus flavus and Aspergillus parasitica,which is widely found in nature.Its toxicity is 10 times of cyanide and 68 times of arsenic,at the same time,it also has mutagenicity,teratogenicity and carcinogenicity.AFB₁ was significantly related to the occurrence and development of human hepatocellular carcinoma,which has not been reported at home and abroad,as a result that it has a good research prospect.The purpose of this study was to investigate the protective effect of EGCG on acute liver injury induced by AFB₁ and to provide clinical evidence for EGCG intervention in AFB₁ induced liver injury.MethodsFifty male Sprague-Dawley?SD?rats were randomly divided into five group:control group,AFB1 model group,EGCG group,EGCG low?25mg/kg?and high?100mg/kg?does treatment group,ten rats in each group.In the fifth day,except control group and EGCG group,other groups set up the acute AFB₁-intoxicated rat model as a single dose of AFB₁?2mg/kg bw?by intraperitoneal injection.In the eighth day,all the rats were sacrificed and then collect blood and organization.Determination of body weight and viscera index,biochemical liver function?ALT,AST,DBIL,ALP?,antioxidant capacity?CAT,GSH,SOD,MDA?,the expression of 8-OHdG in liver tissue and IL-6 in serum were detected by Elisa,and the IL-6 gene and apoptotic gene?Bcl-2,Bax?were detected by PCR,and pathological changes in the hepatictissue were observed with hematoxylin-eosin?HE?staining.Results1.Construction of acute liver injury model in rats induced by AFB₁:The intervention dose of aflatoxin B₁?AFB₁?induced acute liver injury in rats was 2mg/kg?intraperitoneal injection?;2.Effect of EGCG on body weight and visceral index of AFB₁ induced acute liver injury in rats:In AFB₁ group,not only body weight was significantly decreased?P<0.05?,but also liver,spleen and kidney index increased significantly?P<0.05?;Compared with AFB₁ group,the body weight was obviously increased,liver,spleen and kidney index decreased significantly in EGCG high/low groups?P<0.05?.Compared with control group,EGCG group was no significant change in body weight,spleen and kidney index;3.Pathological observation on the effect of EGCG on Acute liver injury induced by AFB₁ in Rats:Liver histopathological examination showed that100mg/kg EGCG could attenuate the acute liver injury induced by AFB₁ in rats,and 100mg/kg EGCG had no effect on the liver of rats;4.Effect of EGCG on serum liver function in rats with acute liver injury induced by AFB_1:After exposure to AFB₁:the liver function index?ALT,AST,TBIL,ALP?of rats was significantly higher than the control group?P<0.05?,EGCG could significantly decrease the damage effect of AFB₁ on the liver of rats,and compared with AFB₁ group,the liver function indexes in EGCG high/low groups were improved obviously?P<0.05?;5.Effect of EGCG on the antioxidation ability of rats with acute liver injury induced by AFB_1:The antioxidation ability of rats was obviously decreased by AFB₁ exposure,compared with the control group,the level of CAT,GSH,SOD in liver tissue decreased?P<0.05?,Serum MDA and 8-OHdG levels in liver tissue were increased?P<0.05?.Compared with the AFB₁group,the antioxidation ability of EGCG was recovered,the level of CAT,GSH,SOD in liver tissue increased in EGCG high/low groups?P<0.05?,Serum MDAs and 8-OHdG levels in liver tissue were decreased?P<0.05?.6.Effect of EGCG on the anti-inflammatory ability of rats with acute liver injury induced by AFB_1:Compared with the control group,the level of serum IL-6 and IL-6 gene expression in liver tissue increased significantly after exposure to AFB₁?P<0.05?;Compared with AFB₁ group,EGCG high/low groups was significantly decreased?P<0.05?.7.Effect of EGCG on the anti-apoptotic ability of rats with acute liver injury induced by AFB_1:Compared with the control group,the expression of Bcl-2 gene,Bcl-2/Bax ratio decreased and the expression of Bax gene increased in the liver tissue of rats exposed to AFB₁?P<0.05?;Compared with the AFB₁group,the expression of Bcl-2 gene,Bcl-2/Bax ratio in EGCG high/low groups increased and the expression of Bax gene decreased in the liver tissue of rats?P<0.05?.ConclusionThe results showed that EGCG had protective effect on the acute liver injury induced by AFB1,which was mainly reflected in the improvement of liver function and the reduction of pathological and oxidative damage of liver tissue.Decrease the level of IL-6 secretion and up-regulate the ratio of bcl-2/bax gene and protein to reduce the apoptosis of hepatocytes.