Toxic Effects Of Maternal Cadmium Intake During Pregnancy On Liver And Kidney Of C57BL/6 Mice

Dietary cadmium intake during gestation is one of the causes of maternal health damage and fetal growth restriction,but the toxicology on maternal liver and kidney is not clear.To explore the redox homeostasis and structure damage in liver and kidney of mice feed with cadmium during gestation,this dissertation is based on an animal model of fetal growth restriction induced by cadmium intake during gestation.We examined the redox homeostasis of maternal liver and kidney on mice feed with cadmium during gestation by detecting changes in enzyme activitives.In addition,we used HE staining and microscopy to explore the organizational structure in liver and kidney of mice feed with cadmium during gestation.There are two contents in our study:First Part.The redox homeostasis of gestational cadmium exposure on the maternal livers and kidneys.The activities of superoxidant dismutase(SOD),catalase(CAT)and glutathione peroxidase(GPx)as well as the contents of malonyldialdehyde(MDA),protein carbonyl(PCO)and DNA-protein cross links(DPC)in liver and kidney of each group of mice were assessed in the liver and kidney of each group.The results showed that the activities of SOD in the liver and kidney of the cadmium treatment group was higher than that of the control group,and it was significantly elevated in the liver of the high concentration cadmium treatment group at E19.5 days.The activities of CAT in liver and kidney increased gradually with the increase of Cd2+concentrations,but gradually decreased with the increase of pregnancy days.With the prolongation of time,there was a different trend of GPx activities in kidney(gradual increase)and liver(gradual decrease).With the increase of Cd2+ concentration,the MDA content in liver gradually increased,and it gradually decreased with the prolongation of pregnancy.The levels of PCO contents in the livers and kidneys increased as theCd2+ concentrations increased.With the increase of Cd2+ concentration and the number of gestation days,the DPC of the liver and kidney of the cadmium treatment group increased.Second Part.The Microstructure effects of gestational cadmium exposure on the maternal livers and kidneys.After staining with HE,the organizational structure in liver and kidney of mice feed with cadmium during gestation were observed under microscope.The results showed that with the increase of Cd2+ intake time and concentration,the organizational structure in liver and kidney of mice feed with cadmium during gestation showed different degrees of pathological changes: the boundaries of liver cells were unclear,the arrangement was disordered,and the central venous cavity was shrunk to varying degrees.In addition,the nucleus was dissolved,the balloon-like change occurred in the high-concentration group.In the kidney,the glomerular endothelial cells proliferaten.In the high-concentration group,the bowman's capsule shrinks,and the glomerulus is slightly swollen.The conclusions are as follow:Firstly,maternal liver and kidney may be the main target organs for fetal growth restriction induced by cadmium intake during pregnancy.Secondly,cadmium intake during pregnancy induces an increase in oxidative stress levels in the maternal liver and kidney.In addition,it leads to damage to proteins,lipids and DNA biomacromolecules in the maternal liver and kidney.These changes can provide a scientific basis for the molecular mechanism of fetal growth restriction caused by maternal cadmium intake during pregnancy.Thirdly,maternal cadmium intake during pregnancy induces tissue-specific oxidative damage in the liver and kidney of mice,probably due to differences in the accumulation of cadmium in the maternal liver and kidney.Fourthly,the structure in liver of mice feed with cadmium during gestation has been affected,and high concentrations of long-termcadmium intake may induce hepatitis.Fifthly,the structure in kidney of mice feed with cadmium during gestation has been affected,but low concentration of short-term cadmium intake has little effect on maternal kidney tissue structure.