Study On Pathogenesis And Prevention Of Congenital Hydronephrosis Induced By 2,3,7,8-Tetrachlorodibenzodioxin

Objective: To research pathogenesis of congenital hydronephrosis induced by 2,3,7,8-tetrachlorodibenzodioxin(TCDD) and the effect of quercetin prevent with the disease.Methods: 1. Animal model of congenital hydronephrosis was constructed with TCDD in mice.Pregnant C57BL/6J mice in treatment group were given TCDD(25μg/kg) with intragastric administration,corn oil was given to pregnant mice with same method in control group on gestational day(GD) 12. Number and survival rate of fetus were calculated,teratogeny of fetus was distinguished,main organs of dams and fetus were gain for histology examination,and ultramicrostructure of fetal kidney and ureter was observed with transmission electron microscope(TEM),on GD18.2. Compare proteomics study on molecular mechanisms of congenital hydronephrosis induced by TCDD in mice. Pregnant C57BL/6J mice in TCDD group were given TCDD(25μg/kg) with intragastric administration,corn oil was given to pregnant mice with same method in control group on GD12. Fetal upper urinary tract tissues were gain for abstracting total protein on GD18. Following,the total protein was separated by two dimensional gel electrophoresis. The differentially expressed proteins between the two groups were compared using image analysis software.The proteins with significant difference were identified by mass spectrometry. The expression of the differential protein was confirmed by immunohistochemistry. Fetal urinary system was gain to culture in vitro, on GD12. Peroxiredoxin 1(Prx 1) protein(final concentration was 1:100) was added in Prx 1 group,same volume nutritive medium was added in control group.After 6 day culture, histology examine was carried out to assess epitheliosis of mucous membrane of ureter and lumina of ureter.3. The effect of quercetin prevent with congenital hydronephrosis induced by TCDD in mice. Pregnant C57BL/6J mice was divided into four groups randomly on GD12.Corn oil was given pregnant mice with intragastric administration in control group,TCDD(25μg/kg) was given in TCDD group,quercetin(100 mg/kg) was given in qercetin group, TCDD(25μg/kg) and quercetin(100 mg/kg) was given in TCDD+qercetin group. Number and survival rate of fetus were calculated,teratogeny of fetus was distinguished, fetal urinary system was gain for histology examine and immunohistochemistry analysis,on GD18. Results: 1.On GD18,incidence rate of bilateral hydronephrosis and hydroureter at superior segment in fetus were 100%(grade 3 hydronephrosis was 86.2%,grade 4 hydronephrosis was 13.8%) in treatment group. Renal interstitial fibrosis, epithelial proliferation in mucous membrane of middle and inferior ureter, narrow ureter lumina was found in fetus with hydronephrosis. Epithelial cells of nephric tubule was swelling with vague and break structure, epithelial cells of ureter was shown with big nucleus, gross nucleoli,rich caryotin,prosperous euchromatin and few heterochromatin,which were found by TEM in treatment group. Fetal kidneys and ureters were normal in control group on GD18. Hydronephrosis incidence of fetal in treatment group was greater than control group(P<0.01).2. Twelve proteins expression was up-regulated in upper urinary tract of mice fetus with hydronephrosis including Prx 1, cadherin 6, gamma-actin, radixin, desmin, type II transforming growth factor-beta receptor, chromogranin B, serum albumin precursor, transferring, hypothetical protein LOC70984, Lipk protein and zinc finger protein 336. Immunohistochemistry analysis display that Prx 1 protein expression was up-regulated in epithelium mucosae of ureter in mice fetus with hydronephrosis. Epitheliosis of mucous membrane of ureter was outstanding, epithelial lamina was thicken and lumina of ureter was narrow after treating with Prx 1 protein compare with control group(P<0.01). 3. Body weight everyday wasn't significant deviation (P>0.05), abortion and immature labor wasn't found, general state of health was normal for pregnance mice in all groups.Number and body weight of fetus wasn't significant deviation(P>0.05),all feus were live,no absorption in all groups.All fetus were normal and no malformation was found in control group and quercetin group on GD18. Incidence rate of bilateral hydronephrosis and hydroureter was 100%(grade 3 hydronephrosis was 84.1%,grade 4 hydronephrosis was 15.9%) in TCDD group fetus on GD18. Incidence rate of bilateral hydronephrosis and hydroureterwas 13.4%(all were grade 3) in TCDD+quercetin group fetus on GD18. The difference of incidence rate between TCDD group and TCDD+quercetin group was significant(P<0.05). Prx 1 protein expression in epithelium of mucous membrane of fetal ureter was negative in control group and quercetin group,was positive in TCDD group,was positive in TCDD+quercetin group fetus with hydronephrosis on GD18. The positive rate for Prx 1 protein expression in epithelium of mucous membrane of fetal ureter was 100% in TCDDgroup,which is greater than TCDD+quercetin group (13.4%)(P<0.05).Conclusion: 1. Pathology of the animal model with congenital hydronephrosis in C57BL/6J fetal mice is similar to ureteropelvic junction obstruction(UPJO) of human being. The animal model is suitable to study on aetiology and pathogenesy of UPJO. 2. Molecular mechanisms of congenital hydronephrosis induced by TCDD in fetal mice is related with Prx 1 protein: oxidative stress is generated by TCDD, following up-regulated Prx 1 protein,which made epithelium mucosae of ureter proliferate and ureteral lumen be narrow.3. Incidence rate congenital hydronephrosis induced by TCDD in C57BL/6J fetal mice may be cut down effectually by quercetin. Effect of quercetin prevent with congenital hydronephrosis is related with that Prx 1 protein expression is inhibited in epithelium of mucous membrane of fetal ureter.