testicle ultrastructure in rats receiving soy diet during gestation, lactation and early development

1
Posters / Reproductive Toxicology 34 (2012) 155–173 173 Chlorpromazine significantly attenuated motor activity and the magnitude of the startle response at all ages tested. MK-801 pro- duced significant increases in time and errors for both strains in the learning and memory assessment. MAM had differential effects on motor activity depending on the age tested, but the effects were similar for WH and SDs. However, differences between the strains in sensitivity to MAM were also evident. MAM treatment produced clear impairments in the learning and memory test for SD rats, but was basically ineffectual for WH rats. MAM did impact both qualitative and quantitative endpoints in the neurological exami- nation for both strains. However, SD rats were much more affected than WH rats in the incidence, type, and severity of the effects seen. Taken together, the present data show limited functional differences between SD and WH rats in most endpoints tested here, however, they do indicate there is differential sensitivity to the developmental neurotoxicant MAM. Ultimately, this may have implications for the preferential selection of one particular strain for standard use in these tests, and may require risk assessment consideration when testing agents with the potential to induce developmental neurotoxicity. http://dx.doi.org/10.1016/j.reprotox.2012.05.084 Testicle ultrastructure in rats receiving soy diet during gesta- tion, lactation and early development Ioannis Papaioannidis a,, Ioannis Kyriakidis b , Theodora Papamitsou a , Ioannis Makaronidis b , Fotios Tsanakalis b , Maria Dermentzopoulou a , Paraskevi Papaioannidou b a Department of Histology and Embryology, Thessaloniki, Greece b Department of Pharmacology, Faculty of Medicine, Aristotle Univer- sity of Thessaloniki, Thessaloniki, Greece Soy and soy products are increasingly used in human diet because of their potential protective effects in cancer and other diseases. Despite their beneficial effects, a concern has been raised among scientists, due to their estrogenic effect. Phytoestrogens contained in soy act as weak estrogenic agonists and bind to estrogen receptors and , and they may disrupt the endocrine system by modulating the hypothalamic-pituitary-gonadal axis. Thus, soy phytoestrogens could influence the development of the reproductive system during crucial stages of life like gestation, lac- tation and early development after birth. The main objective of this study was to test the effect of soy diet on the ultrastructure of male reproductive system in rats that received diet enriched in soy proteins during gestation, lactation and early development. Two groups of male Wistar rats 5 weeks old were used: The par- ents of the animals comprising the study group received ad libitum food enriched in soy protein before mating and during gestation and lactation, while the offspring went on receiving the same food up to the age of five weeks. The control group and their parents received ad libitum the standard food before and during gesta- tion, during lactation and up to the age of five weeks. Both groups were grown under the same conditions and according to the rules of Good Laboratory Practice. The study was approved by the local Ethics Committee. Five weeks after birth, the animals were sac- rificed and specimens of the reproductive organs were prepared and stained for microscopic and electron microscopic examina- tion. The preparations were observed by two different persons, blinded to the source of the specimen. Statistical analysis was per- formed with the statistical package SPSS. No histological difference in the basic structure of the reproductive organs was observed between the study and the control group. The seminiferous tubules, the seminiferous epithelium and the interstitial cells of the testes had no basic differences in both groups. Nevertheless, the num- ber of spermatocytes was lower in the seminiferous tubules of the rats fed with soy during gestation, lactation and early life, com- pared to the rats fed with standard food. The ultrastructure of the spermatocytes in the rats fed with soy appeared with endocyto- plasmic and perinuclear oedema and many mitochondria in the cytoplasm. In some spermatocytes rupture of the nuclear mem- brane and signs of apoptosis were observed. In conclusion, soy diet during gestation, lactation and early development does not have important effects on the basic structure of the reproductive organs of the male rat but it influences the number and the ultrastruc- ture of spermatocytes in the seminiferous tubules of the testes. To our knowledge, this is the first study of the ultrastructure of the reproductive system in male rats fed with soy during early development. http://dx.doi.org/10.1016/j.reprotox.2012.05.085

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the reproductive system in male rats fed with soy during early

Posters / Reproductive T

hlorpromazine significantly attenuated motor activity and theagnitude of the startle response at all ages tested. MK-801 pro-

uced significant increases in time and errors for both strains in theearning and memory assessment. MAM had differential effects on

otor activity depending on the age tested, but the effects wereimilar for WH and SDs. However, differences between the strainsn sensitivity to MAM were also evident. MAM treatment producedlear impairments in the learning and memory test for SD rats,ut was basically ineffectual for WH rats. MAM did impact bothualitative and quantitative endpoints in the neurological exami-ation for both strains. However, SD rats were much more affectedhan WH rats in the incidence, type, and severity of the effectseen. Taken together, the present data show limited functionalifferences between SD and WH rats in most endpoints testedere, however, they do indicate there is differential sensitivity tohe developmental neurotoxicant MAM. Ultimately, this may havemplications for the preferential selection of one particular strainor standard use in these tests, and may require risk assessmentonsideration when testing agents with the potential to induceevelopmental neurotoxicity.

ttp://dx.doi.org/10.1016/j.reprotox.2012.05.084

esticle ultrastructure in rats receiving soy diet during gesta-ion, lactation and early development

oannis Papaioannidis a,∗, Ioannis Kyriakidis b, Theodoraapamitsou a, Ioannis Makaronidis b, Fotios Tsanakalis b, Mariaermentzopoulou a, Paraskevi Papaioannidou b

Department of Histology and Embryology, Thessaloniki, GreeceDepartment of Pharmacology, Faculty of Medicine, Aristotle Univer-ity of Thessaloniki, Thessaloniki, Greece

Soy and soy products are increasingly used in human dietecause of their potential protective effects in cancer and otheriseases. Despite their beneficial effects, a concern has been raisedmong scientists, due to their estrogenic effect. Phytoestrogens

ontained in soy act as weak estrogenic agonists and bind tostrogen receptors � and �, and they may disrupt the endocrineystem by modulating the hypothalamic-pituitary-gonadal axis.hus, soy phytoestrogens could influence the development of the

ogy 34 (2012) 155–173 173

reproductive system during crucial stages of life like gestation, lac-tation and early development after birth. The main objective ofthis study was to test the effect of soy diet on the ultrastructureof male reproductive system in rats that received diet enrichedin soy proteins during gestation, lactation and early development.Two groups of male Wistar rats 5 weeks old were used: The par-ents of the animals comprising the study group received ad libitumfood enriched in soy protein before mating and during gestationand lactation, while the offspring went on receiving the same foodup to the age of five weeks. The control group and their parentsreceived ad libitum the standard food before and during gesta-tion, during lactation and up to the age of five weeks. Both groupswere grown under the same conditions and according to the rulesof Good Laboratory Practice. The study was approved by the localEthics Committee. Five weeks after birth, the animals were sac-rificed and specimens of the reproductive organs were preparedand stained for microscopic and electron microscopic examina-tion. The preparations were observed by two different persons,blinded to the source of the specimen. Statistical analysis was per-formed with the statistical package SPSS. No histological differencein the basic structure of the reproductive organs was observedbetween the study and the control group. The seminiferous tubules,the seminiferous epithelium and the interstitial cells of the testeshad no basic differences in both groups. Nevertheless, the num-ber of spermatocytes was lower in the seminiferous tubules of therats fed with soy during gestation, lactation and early life, com-pared to the rats fed with standard food. The ultrastructure of thespermatocytes in the rats fed with soy appeared with endocyto-plasmic and perinuclear oedema and many mitochondria in thecytoplasm. In some spermatocytes rupture of the nuclear mem-brane and signs of apoptosis were observed. In conclusion, soy dietduring gestation, lactation and early development does not haveimportant effects on the basic structure of the reproductive organsof the male rat but it influences the number and the ultrastruc-ture of spermatocytes in the seminiferous tubules of the testes.To our knowledge, this is the first study of the ultrastructure of

development.

http://dx.doi.org/10.1016/j.reprotox.2012.05.085