Effect Of The Feeding Cry1Ab1Ac Transgenic Rice On Endocrine And Reproduction Functions In Cynomolgus Monkeys

A 12-month feeding study in cynomolgus macaques was performed to evaluate the food safety of Bt rice Huahui 1(HH1),a new type of genetically modified rice that expresses the CrylAb/Ac protein(Bt toxin)and is highly resistant to most lepidopteran pests.Thirty-five male and thirty-five female cynomolgus monkeys(3-5 years old and weight 3 to 5 kg)were randomly divided into seven groups:conventional diet(positive control),conventional diet and BSA,conventional diet and Bt protein,20%non-Genetically Modified rice,20%Genetically Modified rice,60%non-Genetically Modified rice,60%Genetically Modified rice respectively.The blood samples were collected on day-1,30,90,182,209,365.During the feeding trail,clinical observations were conducted daily,and multiple parameters,including body weight,serum hormone level and menstrual cycle were examined at regular intervals.Upon sacrifice,the organs were weighted,and the macroscopic,microscopic and electron microscopic examinations were performed.In addition,the related gene and protein levels were detected.The results show that twelve months of treatment did not yield abnormal observations.Detailed results mainly include the following four aspects.1.Effect of genetically modified rice "HH1”on reproduction functions of male cynomolgus monkeysFor detecting the effects of transgenic rice on the functions of the male cynomolgus monkey reproduction,we mainly measured the following indicators,such as body weight,organs weight,serum testosterone level,the macroscopic,microscopic and electron microscopic examinations of testis and epididymis,the expression of androgen receptor?sperm quality and so on.The results show that no significant difference were observed between the non-GM rice group and GM rice group in the body weight,organs weight,serum testosterone level(P>0.05).No histopathological damages were detected.The androgen receptor and sperm quality were also not significantly different(P>0.05).2.Effect of genetically modified rice "HH1" on endocrine functions of male cynomolgus monkeysThere were no significant difference on organs weight,serum hormones,the expression of TH protein,pituitary and adrenal pathology and ultrastructure of pineal gland.3.Effect of genetically modified rice "HH1" on reproduction functions of female cynomolgus monkeysAfter the female cynomolgus monkeys were fed genetically modified rice "HH1" for six months and ten months,a vaginal smear method was used for identification of the menstrual cycle.After the menstrual cycle was identified,the blood samples were collected in menstrual period,follicular phase,ovulation and luteal phase of female cynomolgus monkeys.Then the serum estradiol,progesterone,LH and FSH levels were measured.The results show that there are no significant difference on serum estradiol,progesterone,LH and FSH level of female cynomolgus monkeys.In addition,the ovaries were fixed with 10%formalin or glutaral,stained with HE staining for histopathological examination and stained with uranium for transmission electron microscope observation.No abnormalities were observed on microscopic pathology analysis.4.Effect of genetically modified rice "HH1" on endocrine functions of female cynomolgus monkeys The following parameters did not significantly differ between the non-GM rice group and GM rice group:organs weight,serum hormone levels,morphological structure of pituitary and adrenal gland and ultrastructure of pineal gland,related gene and protein levels.In summary,the present 12 months primate feeding study results suggests that the transgenic rice HH1 and CrylAb/1 Ac fusion protein has no adverse or toxic effects on the reproduction and endocrine functions of cynomolgus monkeys.This study provides new experimental evidence for the safety evaluation of transgenic rice.