Department of Animal Physiology, University of Warmia and Mazury, Olsztyn, Poland.
Domest Anim Endocrinol. 2013 Jan;44(1):10-8. doi: 10.1016/j.domaniend.2012.07.002. Epub 2012 Aug 10.
The use of soy-based products in pig diets had raised concerns regarding the reproductive toxicity of genistein, the predominant isoflavone in soybeans. Genistein was reported to exhibit weak estrogenic activity but its mechanism of action is not fully recognized. The aim of the study was to examine the in vitro effects of genistein on (1) progesterone (P(4)) and estradiol (E(2)) secretion by porcine granulosa cells harvested from medium follicles, (2) the viability of cultured granulosa cells, and (3) the mRNA and protein expression of estrogen receptors α and β (ERα and ERβ) in these cells. In addition, to verify the role of protein tyrosine kinase (PTK)-dependent mechanisms possibly involved in genistein biological action, we tested the effects of lavendustin C, the nonsteroidal PTK inhibitor, on granulosa cell steroidogenesis. We found that genistein inhibited (P < 0.05) basal P(4) secretion by granulosa cells harvested from medium follicles of pigs. In contrast, lavendustin C did not affect basal P(4) secretion by the cells. Moreover, genistein increased (P < 0.05) basal granulosal secretion of E(2). In contrast, lavendustin C did not alter basal E(2) secretion by porcine granulosa cells. In addition, we demonstrated that genistein increased mRNA and protein expression of ERβ (P < 0.05) in the examined cells. The expression of ERα mRNA was not affected by genistein and ERα protein was not detected in the cultured granulosa cells of pigs. In summary, the genistein action on follicular steroidogenesis in pigs involved changes in the granulosal expression of ERβ. However, the genistein action on P(4) and E(2) production by granulosa cells harvested from medium follicles did not seem to be associated with PTK.
大豆制品在猪饲料中的使用引起了人们对大豆中主要异黄酮染料木黄酮的生殖毒性的关注。据报道，染料木黄酮具有较弱的雌激素活性，但它的作用机制尚未完全被认识。本研究旨在研究染料木黄酮对（1）从中等大小卵泡中采集的猪颗粒细胞分泌的孕酮（P4）和雌二醇（E2）的影响，（2）培养的颗粒细胞的活力，以及（3）这些细胞中雌激素受体α和β（ERα和 ERβ）的 mRNA 和蛋白表达。此外，为了验证蛋白质酪氨酸激酶（PTK）依赖性机制可能参与染料木黄酮的生物学作用，我们测试了非甾体 PTK 抑制剂 lavendustin C 对颗粒细胞甾体生成的影响。我们发现，染料木黄酮抑制（P < 0.05）从中等大小卵泡中采集的猪颗粒细胞的基础 P4 分泌。相比之下，lavendustin C 对细胞的基础 P4 分泌没有影响。此外，染料木黄酮增加了（P < 0.05）基础 granulosal 分泌的 E2。相比之下，lavendustin C 没有改变猪颗粒细胞的基础 E2 分泌。此外，我们证明了染料木黄酮增加了（P < 0.05）所检查细胞中 ERβ 的 mRNA 和蛋白表达。ERα mRNA 的表达不受染料木黄酮的影响，并且在培养的猪颗粒细胞中未检测到 ERα 蛋白。总之，染料木黄酮对猪卵泡甾体生成的作用涉及颗粒细胞中 ERβ 表达的变化。然而，染料木黄酮对从中等大小卵泡中采集的颗粒细胞分泌 P4 和 E2 的作用似乎与 PTK 无关。
