Study Of Regression Effects Of Soy Isoflavone On Mice Endometriosis

Object:To explor the regression effects of soy isoflavone on experimentally induced endometriosis(EM) in rat model.Methods:Sevety adult female ICR mice were divided in to control and endometriosis groups, ten rats that underwent a sham operation were used as control(group A).Endometriosis model was surgically induced in 60 rats by transplanting an autologous fragment of endometrial tissue onto the inner surface of the abdominal wall.Meanwhile,the estradiol-17βwas administered for 3 weeks at 0.5ug/kg s.c.every 3days.Three weeks later,20 rats were killed to assess the implants volume and for pathological examination.The remaining rats were randomly divided into group B(model group,n=10);group C(Low-dose soy isoflavone group,0.5mg/kg/d,n=10),group D (Middle-dose soy isoflavone group,5mg/kg/d,n=10) and group E(High-dose soy isoflavone group,50 mg/kg/d,n=10).Soy isoflavone group rats continued to receive the three different doses,s.c.for 12 weeks.Group A and group B were injected sesame oil 0.05ml daily for 12 weeks. At end of 12 weeks,after collecting blood sample from eyeball,all rats were killed to reassess the implants' size and for histological analysis,blood sample was also taken to determine the serum contents of interleukin-1β(IL-1β) and tumor necrosis factor-α(TNF-α) by ELISA.Results:The rate of induced EM mice model was 73.3%in this experiment.Before and Post treatment,there was no significant implants volume change in group C and(P＞0.05),and the volume was significantly reduced in group D(137.68±20.71 mm~3,88.92±7.46 mm~3),and group E(131.47±19.83 mm~3,36.91±4.46 mm~3,P＜0.05).In the B group,the contents IL-6 and TNF-α(149.38±9.26 pg/ml,45.33±2.44 pg/ml) was significantly increased than that the group A(29.54±6.02 pg/ml,12.92±3.23 pg/ml,P＜0.05),but there was no difference between group C and B(P＞0.05),it's was significantly decreased in group D(103.94±11.33 pg/ml,32.93±4.04 pg/ml) and group E(57.53±8.50 pg/ml,19.33±1.63 pg/ml) compared with the group B(149.38±9.26 pg/ml,45.33±2.44 pg/ml,P＜0.05).After 12 weeks later,in the group C,group D and group E,among the implants volume,serum levels of IL-1βand TNF-αwere positive correlation(P＜0.05).Conclusion:Transplanting an autologous fragment of endometrial tissue onto the inner surface of the abdominal wall,artificial estrus and meanwhile administered the 17β- estrodiol was simple method to induce the experimental EM model in mice,it was a ideal animal model to study Ems.Soy isoflavone caused a satistically significant regression of endometriotic implants, the mechanism may be related with that soy isoflavone restrained the activity of ER,decresed the serum levels of IL-1βand TNF-α.