银耳多糖对SD大鼠的致畸作用

Teratogenicity of tremella fuciformis polysaccharide on SD rats

目的探讨银耳多糖(TFP)对SD大鼠是否存在致畸作用,为TFP的安全评价和开发利用提供实验依据。方法制备TFP,按2.5%、5.0%、10.0%(质量分数)掺入基础饲料,确定实际染毒剂量2.03、4.06、8.43 g/kg三个水平。选择成熟SD大鼠300只,其中雄性100只、雌性200只,受孕后将孕鼠分为阴性对照组、15 mg/kg环磷酰胺(CP)阳性对照组、2.03 g/kg TFP组、4.06 g/kg TFP组、8.43 g/kg TFP组,阴性对照组于孕第6~15 d分别给予基础饲料,各剂量组于孕第6~15 d给予相应饲料,CP组于孕第12 d腹腔注射1次15 mg/kg CP。观察孕鼠生长状况,测量受孕第0、6、9、12、15、20 d的体重、增重、子宫连胎重和净增重。于孕第20 d处死孕鼠,剖腹检查母体受孕情况,记录黄体、着床、吸收胎、活胎、死胎数目等。观察胎仔外观、骨骼、内脏畸形情况,计算畸形率。结果TFP各剂量组的孕鼠行为正常,体重稳步增长,未观察到异常表现和流产情况。与阴性对照组比较,TFP各剂量组孕鼠的体重增重等一般指标差异均无统计学意义(P均>0.05);卵巢黄体数、胎仔的着床数和吸收胎、死胎、活胎分布差异均无统计学意义(P均>0.05);胎仔的一般发育情况、各单项的畸胎率、总畸胎率和畸形窝百分率的差异均无统计学意义(P均>0.05)。TFP的未观察到有害作用剂量(NOAEL)为8.43 g/(kg·bw)。结论根据《食品安全国家标准致畸试验》判定,本次研究未观察到TFP对孕鼠的母体毒性、胚胎发育毒性和致畸性。

Objective To investigate the teratogenic effect of Tremella polysaccharide(TFP)on SD rats,and to provide experimental basis for the safety evaluation and development of TFP.Methods TFP was prepared and mixed into basal feed at 2.5%,5.0%and 10.0%(mass fraction)to determine the actual exposure doses of 2.03,4.06 and 8.43 g/kg.A total of 300 mature SD rats were selected,including 100 males and 200 females.After conception,pregnant rats were divided into negative control group,15 mg/kg cyclophosphamide(CP)positive control group,2.03 g/kg TFP dose group,4.06 g/kg TFP dose group,8.43 g/kg TFP dose group.The negative control group was given basal diet during the 6 th to 15 th day of pregnancy,and each dose group was given corresponding diet on the same time.The CP group was intraperitoneally injected with 15 m g/kg CP once on the 12 th day of pregnancy.The growth status of pregnant mice was observed,and the body weigh t at 0,6,9,12,15,and 20 days after conception,weight gain,uterine interfetal weight and net weight gain were measured.The pregnant rats were sacrificed on the 20 th day of gestation,and the maternal pregnancy was examined by laparotomy.The numbers of corpus luteum,implantation,absorbed fetus,live fetus and stillbirth were recorded.The appearance,bone and viscera deformity of the fetus were observed,and the deformity rate was calculated.Results The pregnant rats of TFP dose groups had normal behavior,and their weight increased steadily.No abnormal manifestations and abortion were observed.Compared with the negative control group,there was no significant difference in body weight gain and other general indicators among pregnant rats in all TFP dose groups(P all>0.05);There was no significant difference in the number of corpus luteum in ovary,the number of implantation in fetus and the distribution of absorbed fetus,stillbirth and live fetus(P all>0.05);There were no significant differences in the general development of the fetus,the rate of malformation in each individual,the total rate of malformation and the percentage of malformed litter(P all>0.05).The NOAEL of TFP was 8.43 g/kg.Conclusion According to the Teratogenicity Test of National Food Safety Standards,no maternal toxicity,embryonic developmental toxicity and teratogenicity of TFP to pregnant mice are observed in this study.