Dynamic Pathological Changes Of Liver In Systemic Seipin Knockout Mice

Objective:To observe the dynamic pathological changes of liver in systemic seipin knockout mice(seipin-s KO)at different ages and to provide a reference for exploring the pathological changes of non-alcoholic fatty liver disease(NAFLD).Method:1.Cross female and male seipin+/-mice,extract the tail DNA of the breeding mice and identify the genotype by PCR.2.Detected changes in blood glucose,body weight,liver weight,and liver weight / weight ratio in the 1 month of age,3 months,5 months,7 months,9 months,and 11 months WT and seipin-s KO groups.3.Paraffin-embedded livers at 1 month,3 months,5 months,7 months,9 months,and 11 months in WT and seipin-s KO groups,hematoxylin-eosin(HE)and Sirius Red staining methods were used to stain embedded liver sections to assess liver histological characteristics at different ages4.Embed sections of spontaneous tumor sites in seipin-s KO group at 7 and 9 months old using HE staining to observe the histological characteristics,compare the tumor formation rate of each group.Result:1.Detected blood glucose in WT group and seipin-s KO group at different ages.The results showed that compared with the WT group,there was no significant change in seipins KO group blood glucose at 1 month of age,The blood glucose levels of seipin-s KO group at 3 months,5 months,7 months,9 months and 11 months were significantly higher than those in the WT group(P < 0.05、P < 0.01);the weight of WT group and seipin-s KO group at different ages were measured,and the results showed that compared with the WT group,seipin-s KO group weight decreased at 1 month of age(P < 0.05);There were no significant changes in the 3 and 7 months seipin-s KO groups,and the weight of the seipins KO groups at 9 and 11 months increased(P < 0.01).The liver weight were significantly different from that of the WT group.There was no statistical difference except for the 1 month old seipin-s KO group.The liver weight in the seipin-s KO groups were significantly higher than that in the WT groups,with a statistical difference(P < 0.001).The results of the liver weight / weight ratio showed that compared with the WT groups,the liver weight / body weight ratio in seipin-s KO groups were significantly increased,except for 1 month of age.Except for the statistical difference,the rest had significant statistical changes(P < 0.001).2.HE staining were used to observe the liver histological characteristics of the WT group and seipin-s KO group.The results showed that as the age of the seipin-s KO groups mice the degree of steatosis gradually increased,and vesicle steatosis were observed in the high-power field of the 1 month old seipin-s KO group;In the liver of the 3 months seipins KO group,obvious vacuole-like changes in the hepatocyte nuclei due to glycogen accumulation were observed;in the liver of the 5 months seipin-s KO groups,large and medium-vesicle mixed steatosis was seen;in the liver of the 7 months seipin-s KO group,circular hollows of various sizes were seen.In the 9 months seipin-s KO group,hepatocytes in the peripheral area of the hepatic lobules were significantly steatotic,and the hepatocytes in the central region were less fatty;in the 11 months seipin-s KO group almost all hepatocytes in the hepatic lobules were steered;but no significant changes in the liver of the WT group.Sirius Red staining results showed that no liver fibrosis were seen in the seipins KO groups at 1 month,3 months and 5 months;in the seipin-s KO groups at 7 months liver cells were deposited along the sinus and surrounded by hepatocytes and the fibrous tissue was fine;fibrosis around the central vein and cells in the 9 months and 11 months seipins KO group.3.Observed whether there are inflammatory infiltration lesions on the basis of steatosis in the WT group and seipin-s KO group at different ages.The results show that there is no obvious inflammatory infiltration in the seipin-s KO group at 1 month;in addition to the pathological changes of steatosis,the liver tissues of mice in the 3 months seipin-s KO group also showed spot-like accumulation of mononuclear cells in the hepatic lobule;in the 5 months seipin-s KO groups hepatocytes were absent in the hepatic lobes,has been replaced by small focal monocytes;the 7 months seipin-s KO group has inflammatory cell infiltration and hepatocyte damage on the basis of medium / bulbar mixed steatosis;9 months seipins KO group the centrally located fat globules were surrounded by surrounding inflammatory cells;in the 11 months seipin-s KO group hepatic lobular inflammation with significant liver cell damage were observed.There were no significant change in the WT group.4.Spontaneous tumors were observed during the pathological changes of liver tissue in the seipin-s KO group.Microscopic observation showed that there were moderate interface inflammation around the seipin-s KO manifold area at 7 months of age.Sexual cell infiltration may be a pathological feature caused by chronic hepatitis.In addition,in addition to the pathological changes observed in hepatitis,the 7 months seipin-s KO mice also showed polycystic liver disease,and its collapsed cysts contained a wavy wall,the cystic cavity is filled with loose fibrous tissue,and the lesion is filled with loose fibrous tissue which is rich in inflammatory cells.One case in 9 months seipin-s KO liver showed a circular exogeneous mass protruding from the liver in gross morphology,and the pathological changes were consistent with the pathological changes of hepatic adenoma of glycogen storage disease(GSD).A clear state,a single tumor without an envelope,adenoma nodules showed bullous steatosis and cell swelling and cytoplasmic staining.The tumor formation rate of spontaneous tumors showed that the tumor formation rate of the 7 months seipin-s KO composition were 2.12% and 9 months seipin-s KO tumor formation rate were 9.09%.Conclusions:In the seipin-s KO group simple fatty liver were common at 1 month of age,and inflammatory infiltration of liver tissue began to appear at 3 months of age.After 7 months of age some mice developed liver as fibrosis until liver tumors.Therefore,seipin-s KO liver pathological changes are similar to the pathological changes of NAFLD,which can provide a basis for exploring the mechanism of NAFLD.