Department of Reproductive Immunology and Pathology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, 10-747 Olsztyn, Poland.
Department of Reproductive Immunology and Pathology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, 10-747 Olsztyn, Poland.
Animal. 2021 Jan;15(1):100048. doi: 10.1016/j.animal.2020.100048. Epub 2020 Dec 10.
The roles of fibroblast growth factor 2 (FGF2) in the corpus luteum (CL) function and its modulatory effect on prostaglandin (PG) F during the bovine estrous cycle were studied using the following design of in vivo and in vitro experiments: (1) effects of FGF2 and FGF receptor 1 inhibitor (PD173074) on bovine CL function in the early (PGF-resistant) and mid (PGF-responsive) luteal stage in vivo, (2) the modulatory effect of FGF2 on PGF action during the luteal phase in vivo and (3) effects of FGF2 and PD173074 on bovine CL secretory function in vitro. Cows were treated by injection into the CL with: (1) saline (control), (2) FGF2, (3) PD173074, (4) FGF2 followed by intramuscular (i.m.) PGF, (5) PD173074 followed by i.m. PGF and (6) i.m. PGF as a positive control. For in vitro experiments, CL explants were treated with the aforementioned factors. Progesterone (P) concentrations of blood samples or culture media were determined by radioimmunoassay. Relative mRNA expressions of the genes involved in angiogenesis and steroidogenesis were determined by quantitative real-time PCR. Although FGF2 treatment on day 4 of the estrous cycle did not change the cycle length, FGF2 with PGF decreased the P concentrations observed during the estrous cycle compared to the control group (P < 0.001). Moreover, FGF2 treatment on day 10 prolonged CL function as indicated by a significantly greater concentration of P on day 21 compared to the control group. In the in vitro study, FGF2 decreased cytochrome P450 family 11 subfamily A member 1 (CYP11A1) and hydroxy-delta-5-steroid dehydrogenase (HSD3B1) mRNA expression (P < 0.01) and decreased P production in the early-stage CL (P < 0.001). However, FGF2 + PGF or PGF alone resulted in an elevation of steroidogenic acute regulatory protein and CYP11A1 mRNA expression and P secretion in the early-stage CL (P < 0.01). In the mid-luteal phase, FGF2 upregulated CYP11A1 and HSD3B1 mRNA expression (P < 0.01), while FGF2 + PGF increased only HSD3B1 mRNA expression (P < 0.001). In conclusion, FGF2 seems to play a modulatory role in CL development or luteolysis, differentially regulating steroidogenesis and angiogenic factors as well as PGF actions.
本文通过体内和体外实验设计，研究了成纤维细胞生长因子 2（FGF2）在黄体（CL）功能中的作用及其对牛发情周期中前列腺素（PG）F 的调节作用：（1）FGF2 和 FGF 受体 1 抑制剂（PD173074）对牛发情周期早期（PGF 抗性）和中期（PGF 反应性）黄体功能的影响；（2）FGF2 在体内黄体期对 PGF 作用的调节作用；（3）FGF2 和 PD173074 对牛 CL 分泌功能的体外影响。通过向 CL 注射以下物质处理奶牛：（1）生理盐水（对照）、（2）FGF2、（3）PD173074、（4）FGF2 后肌肉内（i.m.）PGF、（5）PD173074 后肌肉内（i.m.）PGF 和（6）i.m. PGF 作为阳性对照。对于体外实验，用上述因子处理 CL 外植体。通过放射免疫测定法测定血样或培养物中孕酮（P）浓度。通过实时定量 PCR 测定参与血管生成和类固醇生成的基因的相对 mRNA 表达。尽管发情周期第 4 天的 FGF2 处理并未改变周期长度，但 FGF2 与 PGF 联合使用与对照组相比降低了发情周期中观察到的 P 浓度（P<0.001）。此外，发情周期第 10 天的 FGF2 处理延长了 CL 功能，第 21 天的 P 浓度明显高于对照组。在体外研究中，FGF2 降低了细胞色素 P450 家族 11 亚家族 A 成员 1（CYP11A1）和羟基-delta-5-类固醇脱氢酶（HSD3B1）的 mRNA 表达（P<0.01），并降低了早期 CL 中的 P 产生（P<0.001）。然而，FGF2+PGF 或 PGF 单独使用可导致类固醇生成急性调节蛋白和 CYP11A1 mRNA 表达以及早期 CL 中的 P 分泌升高（P<0.01）。在中期黄体期，FGF2 上调了 CYP11A1 和 HSD3B1 的 mRNA 表达（P<0.01），而 FGF2+PGF 仅增加了 HSD3B1 的 mRNA 表达（P<0.001）。总之，FGF2 似乎在 CL 发育或黄体溶解中发挥调节作用，差异调节类固醇生成和血管生成因子以及 PGF 作用。
