The Antagonism Effect Of Polysaccharide Agaricus Blazei Murill On Cadmium-induced Liver Damage In Chicken

This study aimed to assess the protective roles of polysaccharides from Agaricus blazei Murill(ABP)against cadmium(Cd)-induced damage in chicken livers.A total of 80 Hy-Line laying chickens(7 days old)were random Ly divided into four groups(n=20).Group I(control group)was fed with a basic diet and 0.2 mL saline per day,Group II(model group)was fed with a basic diet containing 140mg/kg cadmium chloride(Cd Cl2)and 0.2 m L saline per day,Group III(treatment group)was fed with a basic diet containing 140 mg/kg Cd Cl2 and 0.2 m L ABP solution(30 mg/m L)per day via oral gavage,and Group IV(ABP group)was fed with 0.2 mL ABP solution(30 mg/m L)per day via oral gavage.The feeding experiment lasted for 60 days,and the experimental animals had free access to food and water.On days 20,40,and 60,livers of five chickens in each group were collected after euthanasia.Observe the histopathological changes of chicken livers with H&E staining.Detect the activities of antioxidant enzymes(SOD and GSH-PX),the content of MDA and the activities of aminotransferase(ALT and AST)with corresponding kits.Determine the mRNA and protein levels of inflammatory cytokines(TNF-α,IL-1β,and IL-6)via qPCR method and ELISA method.And the mRNA levels of HSPs(HSP 27,40,60,70,and 90)and protein levels of HSPs(HSP60,70,and 90)were detected with q PCR method and Western blot respectively.The results showed that compared with the Group control,intaking Cd continuously lead to the accumulation of Cd in chicken liver,which resulted in tumidness and inflammation of liver and degeneration and necrosis of liver cell.The activities of aminotransferase(ALT and AST)and antioxidant enzymes(SOD and GSH-PX)of chicken in Group Model were significantly inhibited compared with that those of chicken in Group Control(P <0.05).The content of MDA in Group Model is also significantly decreased compared with Group Control(P <0.05).In addition,the mRNA and protein levels of inflammatory cytokines(TNF-α,IL-1β,and IL-6)in chicken livers of Group Model were significantly elevated compared with Group Control(P <0.05).And the mRNA levels of HSPs(HSP 27,40,60,70,and 90)and protein levels of HSPs(HSP60,70,and 90)in chicken livers of Group Model were all significantly increased compared with Group Control(P <0.05).Meanwhile,compared with Group Model,the content of Cd in chicken livers of Group Treatment was significantly decreased(P <0.05),so that the activities of the antioxidant enzymes(SOD and GSH-PX)and the aminotransferase(ALT and AST)were significantly increased(P <0.05),and the content of MDA was significantly decreased in chicken livers of Group Treatment when compared with Group Model(P <0.05).Besides,compared with group Model,the mRNA and protein levels of inflammatory cytokines(TNF-α,IL-1β,and IL-6)in chicken livers of Group Treatment weresignificantly decreased(P <0.05).And the m RNA levels of HSPs(HSP 27,40,60,70,and 90)and protein levels of HSPs(HSP60,70,and 90)in Group Treatment were significantly decreased when compared with those in Group Control(P <0.05).While the above indexes of chicken in Group ABP showed no significant difference with those in Group Control(P>0.05).The results indicated that ABP could partly ameliorate the toxic effects of Cd on chicken livers.This research provides theoretical foundation for the further study on the mechnism of the antagonism of ABP on Cd-induced chicken liver damage.