Department of Bioproduction, Graduate School of Bioindustry, Tokyo University of Agriculture, Abashiri, Hokkaido, 099-2493, Japan.
Department of Bioproduction, Faculty of Bioindustry, Tokyo University of Agriculture, Abashiri, Hokkaido, 099-2493, Japan.
Theriogenology. 2024 Sep 15;226:228-235. doi: 10.1016/j.theriogenology.2024.06.017. Epub 2024 Jun 21.
Although anti-Müllerian hormone (AMH) is involved in the regulation of granulosa cell function in female animals, its role in tissues other than ovarian follicles remains poorly understood. It has also been suggested that cows with high circulating AMH concentrations have increased fertility; however, the mechanism has not been elucidated. This study was conducted to identify the presence of the AMH-signaling system and its target cells in the bovine corpus luteum formed from an ovulated follicle. Immunoblotting revealed that the proteolytically cleaved C-terminal region in AMH (AMH), a biologically active peptide, was present in trace amounts in the early corpus luteum and significantly increased during the mid to regressed stages. AMH and cleaved N-terminal region (AMH) in AMH generate a noncovalent isoform that improves the activity of AMH signaling. An immunohistochemical analysis revealed that AMH, AMH, and type II AMH receptor (AMHR2) were localized to luteal cells during the entire estrous cycle. AMH in the corpus luteum seemed to be newly synthesized since AMH expression was detected. These findings suggest that AMH signaling is involved in the regulation of luteal cell function through an autocrine and post-translational processing mechanism. The level of AMHR2 and mRNA expression of AMHR2 and type I AMH receptors (activin-like kinase 2, 3, and 6) were highest in the mid stage. Thus, AMH signaling in the corpus luteum may also be regulated by changes in the receptor levels. Since the transforming growth factor-beta superfamily, to which AMH belongs, is a multifunctional polypeptide growth factor, further studies are needed to evaluate whether AMH signaling has a role in facilitating or inhibiting luteal cell functions.
虽然抗缪勒管激素 (AMH) 参与了雌性动物颗粒细胞功能的调节，但它在卵巢卵泡以外的组织中的作用仍知之甚少。也有人提出，循环中 AMH 浓度高的奶牛具有更高的生育能力；然而，其机制尚未阐明。本研究旨在鉴定存在于从排卵卵泡形成的牛黄体中的 AMH 信号系统及其靶细胞。免疫印迹显示，AMH（AMH）的蛋白水解切割 C 端区域（一种生物活性肽）在早期黄体中痕量存在，并在中期至退化阶段显著增加。AMH 和 AMH 的切割 N 端区域（AMH）生成一种非共价同型物，可提高 AMH 信号的活性。免疫组织化学分析显示，AMH、AMH 和 II 型 AMH 受体（AMHR2）在整个发情周期均定位于黄体细胞。由于检测到 AMH 的表达，黄体中的 AMH 似乎是新合成的。这些发现表明，AMH 信号通过自分泌和翻译后加工机制参与黄体细胞功能的调节。黄体中 AMHR2 的水平和 AMHR2 和 I 型 AMH 受体（激活素样激酶 2、3 和 6）的 mRNA 表达在中期最高。因此，黄体中 AMH 信号也可能受到受体水平变化的调节。由于 AMH 所属的转化生长因子-β超家族是一种多功能多肽生长因子，因此需要进一步研究来评估 AMH 信号是否在促进或抑制黄体细胞功能方面发挥作用。
