Graduate Program in Cell and Structural Biology, Institute of Biology, University of Campinas-UNICAMP, Campinas, SP, Brazil.
Reprod Biol Endocrinol. 2011 Jun 24;9:94. doi: 10.1186/1477-7827-9-94.
Recent studies have supported the concept of "fetal programming" which suggests that during the intrauterine development the fetus may be programmed to develop diseases in adulthood. The possible effects of in utero protein restriction on sexual development of rat male offspring were evaluated in the present study.
Pregnant Wistar rats were divided into two experimental groups: one group treated with standard chow (SC, n = 8, 17% protein) and the other group treated with hypoproteic chow (HC, n = 10, 6% protein) throughout gestation. After gestation the two experimental groups received standard chow. To evaluate the possible late reproductive effects of in utero protein restriction, the male offspring of both groups were assessed at different phases of sexual development: prepubertal (30 days old); peripubertal (60 days old); adult (90 days old). Student's t-test and Mann-Whitney test were utilized. Differences were considered significant when p < 0.05.
We found that in utero protein restriction reduced the body weight of male pups on the first postnatal day and during the different sexual development phases (prepubertal, peripubertal and adult). During adulthood, Sertoli cell number, sperm motility and sperm counts in the testis and epididymal cauda were also reduced in HC. Furthermore, the numbers of sperm presenting morphological abnormalities and cytoplasmic drop retention were higher in HC.
In conclusion, in utero protein restriction, under these experimental conditions, causes growth delay and alters male reproductive-system programming in rats, suggesting impairment of sperm quality in adulthood.
最近的研究支持“胎儿编程”的概念，该概念表明，在宫内发育过程中，胎儿可能会被编程为在成年后发展出疾病。本研究评估了宫内蛋白质限制对雄性仔鼠性发育的可能影响。
将怀孕的 Wistar 大鼠分为两组实验组：一组用标准饲料（SC，17%蛋白质）喂养（n = 8），另一组用低蛋白饲料（HC，6%蛋白质）喂养整个孕期。妊娠结束后，两组实验组均接受标准饲料。为了评估宫内蛋白质限制对后期生殖的可能影响，对两组雄性仔鼠进行了不同性发育阶段的评估：青春期前（30 日龄）；青春期（60 日龄）；成年（90 日龄）。使用学生 t 检验和曼-惠特尼检验。当 p < 0.05 时，认为差异具有统计学意义。
我们发现，宫内蛋白质限制降低了雄性幼鼠出生后第一天和不同性发育阶段（青春期前、青春期和成年）的体重。在成年期，HC 还降低了睾丸和附睾尾部的支持细胞数量、精子活力和精子计数。此外，HC 中出现形态异常和细胞质滴保留的精子数量较高。
总之，在这些实验条件下，宫内蛋白质限制导致生长迟缓，并改变了雄性生殖系统的编程，提示成年期精子质量受损。
