Dance A, Kastelic J, Thundathil J
Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, 3330 Hospital Dr. NW Calgary, AB T2N 4N1, Canada.
Reprod Fertil Dev. 2017 Aug;29(8):1635-1641. doi: 10.1071/RD16122.
Beef and dairy bull calves fed a low-nutrition diet during early life had decreased concentrations of circulating insulin-like growth factor I (IGF-I), delayed increases in testosterone, smaller testes and delayed puberty compared with those fed high-nutrition diets. Although IGF-1 has important roles in Sertoli cell function in rats and mice, this has not been well documented in bulls. The objectives of this study were to: (1) isolate Sertoli cells from bull calves at 8 weeks of age, (2) culture them in vitro and (3) determine the effects of IGF-I, FSH and a combination of both hormones on cell proliferation. For Sertoli cell isolation, minced testicular tissues were treated with collagenase followed by trypsin and hyaluronidase to digest seminiferous tubules and release Sertoli cells. In this study, Sertoli cells were successfully isolated from 8-week-old Holstein bull calves (n=4) and these cells were cultured for up to 8 days. A combination of IGF-I and FSH increased proliferation (~18%) and therefore cell number (1.5-fold) of prepubertal bovine Sertoli cells in culture, providing clear evidence that IGF-I has a similar role in bovine Sertoli cells as reported in rodents.
与喂食高营养日粮的公牛犊相比，在生命早期喂食低营养日粮的肉牛和奶牛公牛犊，其循环胰岛素样生长因子I（IGF-I）浓度降低，睾酮升高延迟，睾丸较小且青春期延迟。尽管IGF-1在大鼠和小鼠的支持细胞功能中具有重要作用，但在公牛中尚未得到充分证明。本研究的目的是：（1）从8周龄的公牛犊中分离支持细胞，（2）进行体外培养，（3）确定IGF-I、促卵泡激素（FSH）以及两种激素组合对细胞增殖的影响。对于支持细胞的分离，将切碎的睾丸组织先用胶原酶处理，然后用胰蛋白酶和透明质酸酶消化生精小管并释放支持细胞。在本研究中，成功从8周龄的荷斯坦公牛犊（n = 4）中分离出支持细胞，并将这些细胞培养长达8天。IGF-I和FSH的组合可使培养的青春期前牛支持细胞的增殖增加（约18%），从而使细胞数量增加（1.5倍），这清楚地证明了IGF-I在牛支持细胞中的作用与在啮齿动物中报道的相似。
