The Study Of The Effects And Mechanism Of Chitosan Selenium Against Zearalenone

Zearalenone（Zearalenone,ZEN）is a kind of estrogenic mycotoxin,which has toxicities of reproductive development and immunity,pose serious threats to animal health and food safety.The important pathological basis of ZEN are apoptosis,oxidative damage and immunosuppression.Researches found that both chitosan and selenium can improve the antioxidant capacity and immunity of body.Chitosan-Se is a new kind of organic selenium,playing a dual role of chitosan and organic selenium.This experiment research the effect of chitosan-Se resist ZEN toxicity in vitro and in vivo,and exploring the mechanism of chitosan-Se resist ZEN from oxidative damage and apoptosis.Aim to provide the theoretical basis and technical support for the popularization and application of chitosan selenium.The main contents were as followings:1.Establish a method to culture porcine endometrial epithelial cells in vitro.Take tissue block method to isolate,purify and culture the endometrial epithelial cells.The results showed that: large numbers of porcine endometrial epithelial cells were obtained by tissue block method,which were spherical and active.After purification by differential digestion,the epithelial cells were normal and grow as slabstone,that the growth curve was double "S" shape.RT-PCR detected the presence of Cytokeratin 18 in epithelial cells,which affirmed the cultured cells were endometrial epithelial cells.2.Research the antagonistic effects of chitosan-Se resist ZEN toxicity in vitro.The experiment divided into 5 groups: that control group,ZEN group,ZEN-0.5Se group（0.5mol/L Se+ZEN）,ZEN-1.5Se group（1.5 mol/L Se+ZEN）and ZEN-3Se group（3mol/L Se+ZEN）.Determined the activity of antioxidant enzymes and GPX-1,TNF-α,ERα,ERβ,Bax and Bcl-2 m RNA.The results showed that: the activity of T-AOC and GSH-Px in group ZEN were extremely significantly lower than that in C group（P<0.01）;the activity of T-AOC in ZEN-1.5Se and ZEN-3Se group were extremely significantly higher than that in ZEN group（P<0.01）;the activity of SOD in ZEN-3Se group were extremely significantly higher than that in ZEN group（P<0.01）;the content of MDA in ZEN-1.5Se and ZEN-3Se group were significantly lower than that in ZEN group（P<0.05）.The expression of ERβ and Bcl-2m RNA in ZEN group were significantly lower than that in C group（P<0.05）,also the expression of GPX-1 and TNF-α m RNA were lower than C group,but no significant;while,the expression of Bax m RNA were extremely significantly higher than that in C group（P<0.01）.The expression of GPX-1 m RNA in ZEN-1.5Se and ZEN-3Se were significantly higher than that in ZEN group（P<0.05）,and TNF-α,ERβ m RNA expression in ZEN-3Se were significantly higher than that in ZEN group（P<0.05）.The expression of Bax m RNA in ZEN-0.5Se,ZEN-1.5Se and ZEN-3Se were extremely significantly lower than that in ZEN group（P<0.01）.The results indicated that the effects of different concentrations of chitosan-Se on the activity of T-AOC,GSH-Px and SOD in the endometrial epithelial cells cultured with ZEN are improved or tendency;the effects of different concentrations of chitosan-Se on the expression of GPX-1,TNF-α and ERβ m RNA in the endometrial epithelial cells cultured with ZEN,showed increase trend（0.5 mol/LSe and 1.5 mol/LSe）or improved（3 mol/LSe）,while decreased the expression of Bax m RNA.3.Research the effects of chitosan selenium effects on the growth performance,blood biochemistry,antioxidant function and content of estradiol of mice fed with ZEN.60 female mice,divided into control group,ZEN group,ZEN-Se1 group,ZEN-Se2 group and ZEN-Se3 group,randomly.And fed with basal diet,added 2mg/kg ZEN basal diet,add 2 mg/kg ZEN and 0.2 mg/kg Se diet,2mg/kg ZEN and 0.4 mg/kg Se diet,2mg/kg ZEN and 0.6 mg/kg Se diet,respectively.The test lasts 30 days.After the experiment,recorded the dietary consumption and weight gain;determined the biochemical parameters,the activities of antioxidant enzyme in blood,liver and kidney,and the content of Ig A,Ig M,Ig G,IFN-γ,IL-2and E2 in serum.The results indicated that chitosan selenium had no effects on the growth performance of mice fed with ZEN;high concentration（0.6 mg/kg）of chitosan selenium could reduce the content of plasma AST in mice fed with ZEN;chitosan selenium could increase the antioxidant capacity of blood,liver and kidney of mice fed with ZEN,and chitosan selenium could reduce the content of E2 in mice fed with ZEN.4.Research the effects of chitosan selenium on the expression of genes in mice fed with ZEN.Test groups and animal treatment were the same as experiment 3.Collecting sterile liver and uterus,determined the expression of IFN-γ,IL-2,CYP3A11,3α-HSD,3β-HSD m RNA in liver and ERα,ERβ m RNA in uterus.The results showed that the expression of IFN-γ and IL-2 m RNA in ZEN-Se3 group were extremely significantly higher than that in ZEN group（P<0.01）,the expression of CYP3A11 m RNA in ZEN-Se2 and ZEN-Se3 group were extremely significantly higher than that in ZEN group（P<0.01）,the expression of 3α-HSD,3β-HSD m RNA in ZEN-Se3 group were significantly or extremely higher than that in ZEN group（P<0.05 or P<0.01）.The expression of ERα m RNA in ZEN group were extremely significantly higher than that in C group（P<0.01）,while the ERβ m RNA significantly lower than that in C group（P<0.05）.The expression of ERα m RNA in ZEN-Se2 and ZEN-Se3 group were significantly lower than that in ZEN group（P<0.05）,The expression of ERβm RNA in ZEN-Se3 group were extremely significantly higher than that in ZEN group（P<0.01）.These results indicated that high concentration（0.6 mg/kg）of chitosan selenium could increase the expression of IFN-γ and IL-2 m RNA in liver of mice fed with ZEN;The effect of different concentrations of chitosan selenium on the expression of CYP3A11 m RNA in the liver of mice fed with ZEN showed an increasing trend（0.2 mg/kg）or effect（0.4mg/kg and 0.6 mg/kg）,while a decreasing trend（0.2 mg/kg and 0.4 mg/kg）or effect（0.6mg/kg）of 3α-HSD,3β-HSD m RNA in the liver of mice fed with ZEN.The effect of different concentrations of chitosan selenium on the expression of ERα m RNA in uterus of mice fed with ZEN showed a decreasing trend（0.2 mg/kg）or effect（0.4 mg/kg and 0.6 mg/kg）,and an increasing trend（0.2 mg/kg and 0.4 mg/kg）or effect（0.6 mg/kg）of ERβ m RNA in uterus of mice fed with ZEN.