Amweg A N, Rodríguez F M, Huber E, Marelli B E, Gareis N C, Belotti E M, Rey F, Salvetti N R, Ortega H H
Instituto de Ciencias Veterinarias del Litoral (ICiVet-Litoral)Universidad Nacional del Litoral (UNL) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Esperanza, Santa Fe, Argentina.
Instituto de Ciencias Veterinarias del Litoral (ICiVet-Litoral)Universidad Nacional del Litoral (UNL) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Esperanza, Santa Fe, Argentina
Reproduction. 2017 Apr;153(4):433-441. doi: 10.1530/REP-16-0493. Epub 2017 Jan 9.
Glucocorticoids (GCs) such as cortisol and corticosterone are important steroid hormones with different functions in intermediate metabolism, development, cell differentiation, immune response and reproduction. In response to physiological and immunological stress, adrenocorticotropic hormone (ACTH) acts on the adrenal gland by stimulating the synthesis and secretion of GCs. However, there is increasing evidence that GCs may also be synthesized by extra-adrenal tissues. Here, we examined the gene and protein expression of the enzyme 11β-hydroxylase P450c11 (CYP11B1), involved in the conversion of 11-deoxycortisol to cortisol, in the different components of the bovine ovary and determined the functionality of CYP11B1 in vitro CYP11B1 mRNA was expressed in granulosa and theca cells in small, medium and large antral ovarian follicles, and CYP11B1 protein was expressed in medium and large antral follicles. After stimulation by ACTH, we observed an increased secretion of cortisol by the wall of large antral follicles. We also observed a concentration-dependent decrease in the concentration of cortisol in response to metyrapone, an inhibitor of CYP11B1. This decrease was significant at 10 µM metyrapone. In conclusion, this study demonstrated for the first time the presence of CYP11B1 in the bovine ovary. This confirms that there could be a local synthesis of GCs in the bovine ovary and therefore a potential endocrine responder to stress through these hormones.
皮质醇和皮质酮等糖皮质激素（GCs）是重要的类固醇激素，在中间代谢、发育、细胞分化、免疫反应和生殖过程中具有不同功能。在生理和免疫应激反应中，促肾上腺皮质激素（ACTH）通过刺激GCs的合成和分泌作用于肾上腺。然而，越来越多的证据表明，GCs也可能由肾上腺外组织合成。在此，我们检测了参与将11-脱氧皮质醇转化为皮质醇的11β-羟化酶P450c11（CYP11B1）在牛卵巢不同组分中的基因和蛋白表达，并在体外确定了CYP11B1的功能。CYP11B1 mRNA在小、中、大窦状卵泡的颗粒细胞和卵泡膜细胞中表达，CYP11B1蛋白在中、大窦状卵泡中表达。经ACTH刺激后，我们观察到大型窦状卵泡壁分泌的皮质醇增加。我们还观察到，作为CYP11B1抑制剂的甲吡酮可使皮质醇浓度呈浓度依赖性降低。在10 μM甲吡酮时，这种降低具有显著性。总之，本研究首次证明了CYP11B1在牛卵巢中的存在。这证实了牛卵巢中可能存在GCs的局部合成，因此可能通过这些激素对应激产生潜在的内分泌反应。
