Department of Animal Production, School of Agriculture, The University of Jordan, Amman, Jordan.
Department of Animal Science, University of Nebraska-Lincoln, Lincoln, NE 68583, USA.
J Anim Sci. 2022 Jun 1;100(6). doi: 10.1093/jas/skac151.
Beef cows with excess androstenedione (A4; High A4) in follicular fluid (FF) and secreted by the ovarian cortex have been reported from the University of Nebraska-Lincoln physiology herd displaying characteristics reminiscent of polycystic ovary syndrome (PCOS). Thus, we hypothesized that naturally occurring High A4 cows were present in other dairy and beef herds. Fourteen Jordan (Amman, Jordon) dairy heifers and 16 U.S. Meat Animal Research Center beef heifers were classified by FF (High A4: A4 > 40 ng/mL and Control: A4 < 20 ng/mL) and/or cortex culture media (High A4 > 1 ng/mL/d or Control < 1 ng/mL/d). High A4 dairy heifers (n = 6) had greater A4 concentrations (7.6-fold) in FF and (98-fold) greater in ovarian cortex culture media with greater numbers of primordial and fewer later-stage follicles than Controls (n = 8) even after 7 d of culture. Also, the ovarian cortex had greater staining for Picro Sirius red in High A4 dairy heifers compared with Controls indicating increased fibrosis. Thecal cells from High A4 dairy heifers had greater STAR, LHCGR, CYP17A, CD68, and PECAM mRNA expression with increased mRNA abundance of CYP17A1 and CD68 in the ovarian cortex cultures compared with Control dairy heifers. Similarly, cortex culture media from High A4 beef heifers (n = 10) had increased A4 (290-fold; P ≤ 0.001), testosterone (1,427-fold; P ≤ 0.001), and progesterone (9-fold; P ≤ 0.01) compared with Control heifers with increased primordial follicles and decreased later-stage follicles even after 7 d of culture, indicating abnormal follicular development. High A4 ovarian cortex cultures from beef heifers also had increased fibrosis markers and greater expression of PECAM (P = 0.01) with a tendency for increased vascular endothelial cadherin compared with Controls (n = 6). These two trials support our hypothesis that naturally occurring androgen excess cows are present in other dairy and beef herds. The ability to identify these females that have excess A4 ovarian microenvironments may allow for their use in understanding factors causing abnormal follicle development linked to androgen excess and inflammation.
从内布拉斯加大学林肯分校生理学群体中报道的具有过量雄烯二酮（A4；高 A4）的奶牛的卵泡液（FF）和卵巢皮质中分泌的牛，具有多囊卵巢综合征（PCOS）的特征。因此，我们假设在其他奶牛和肉牛群中存在天然存在的高 A4 牛。14 头约旦（安曼，约旦）奶牛小母牛和 16 头美国肉用动物研究中心肉牛小母牛根据 FF（高 A4：A4>40ng/ml 和对照：A4<20ng/ml）和/或皮质培养基（高 A4>1ng/ml/d 或对照<1ng/ml/d）进行分类。高 A4 奶牛小母牛（n=6）的 FF（7.6 倍）和卵巢皮质培养基（98 倍）中 A4 浓度更高，与对照（n=8）相比，原始卵泡数量更多，后期卵泡数量更少，即使在培养 7 天后也是如此。此外，与对照相比，高 A4 奶牛小母牛的卵巢皮质中 Picro Sirius 红染色更强，表明纤维化增加。与对照奶牛小母牛相比，高 A4 奶牛小母牛的颗粒细胞层细胞中的 STAR、LHCGR、CYP17A、CD68 和 PECAM mRNA 表达更高，卵巢皮质培养物中的 CYP17A1 和 CD68 mRNA 丰度增加。同样，高 A4 肉牛小母牛（n=10）的皮质培养基中的 A4（290 倍；P≤0.001）、睾酮（1427 倍；P≤0.001）和孕酮（9 倍；P≤0.01）增加与对照小母牛相比，原始卵泡增加，后期卵泡减少，即使在培养 7 天后也是如此，表明卵泡发育异常。来自肉牛小母牛的高 A4 卵巢皮质培养物也具有更高的纤维化标志物和 PECAM 的更高表达（P=0.01），并且与对照（n=6）相比，血管内皮钙黏蛋白的表达有增加的趋势。这两项试验支持我们的假设，即在其他奶牛和肉牛群中存在天然存在的雄激素过多牛。识别具有过量 A4 卵巢微环境的这些雌性动物的能力可能使其能够用于理解导致与雄激素过多和炎症相关的异常卵泡发育的因素。
