Rak Agnieszka, Drwal Eliza, Karpeta Anna, Gregoraszczuk Ewa Ł
Department of Physiology and Toxicology of Reproduction, Institute of Zoology, Jagiellonian University in Krakow, Krakow, Poland
Department of Physiology and Toxicology of Reproduction, Institute of Zoology, Jagiellonian University in Krakow, Krakow, Poland.
Biol Reprod. 2015 Jun;92(6):142. doi: 10.1095/biolreprod.115.128611. Epub 2015 Apr 29.
Resistin, a hormone secreted by adipocytes, is thought to be important in reproduction. Our previous study demonstrated resistin expression in porcine ovarian follicles and its direct effect on steroidogenesis. The aim of the current study was to evaluate the effect of gonadotropins and the local ovarian factors, such as insulin-like growth factor type 1 (IGF1) and steroids (progesterone, testosterone, and 17 beta-estradiol), on the expression and secretion of resistin, as well as its steroidogenic action. Porcine ovarian follicles were exposed to follicle-stimulating hormone (FSH) and luteinizing hormone (LH) at 50-150 ng/ml, IGF1 (10-100 ng/ml), and steroids at 10(-8) to 10(-6) M for 24 h. Then, mRNA, protein expression, and medium concentration of resistin were determined using real-time PCR, Western blot analysis, and ELISA, respectively. In the subsequent experiments, ovarian follicles were exposed to resistin and/or FSH, LH, IGF1, and steroids, and ovarian steroidogenesis was analyzed. Additionally, we examined the direct effect of resistin on the protein expression of receptors for gonadotropins and investigated local factors. The results showed that gonadotropins and steroids have stimulatory effects but that IGF1 has an inhibitory effect on resistin expression and secretion. Resistin decreased gonadotropins and local hormone-induced steroid secretion and inhibited 3beta-hydroxysteroid dehydrogenase, 17beta-hydroxysteroid dehydrogenase, and cytochrome P450 aromatase protein expression. Additionally, we demonstrated that resistin increased the expression of receptors for progesterone and testosterone. These findings all show that the expression and function of resistin are regulated by gonadotropins and local factors produced by ovarian follicles.
抵抗素是一种由脂肪细胞分泌的激素，被认为在生殖过程中起重要作用。我们之前的研究表明，抵抗素在猪卵巢卵泡中表达，并对类固醇生成有直接影响。本研究的目的是评估促性腺激素以及卵巢局部因子，如胰岛素样生长因子1（IGF1）和类固醇（孕酮、睾酮和17β-雌二醇）对抵抗素表达、分泌及其类固醇生成作用的影响。将猪卵巢卵泡暴露于50 - 150 ng/ml的促卵泡激素（FSH）和黄体生成素（LH）、10 - 100 ng/ml的IGF1以及10(-8)至10(-6) M的类固醇中24小时。然后，分别使用实时PCR、蛋白质印迹分析和酶联免疫吸附测定法测定抵抗素的mRNA、蛋白质表达和培养基浓度。在后续实验中，将卵巢卵泡暴露于抵抗素和/或FSH、LH、IGF1和类固醇中，并分析卵巢类固醇生成。此外，我们研究了抵抗素对促性腺激素受体蛋白质表达的直接影响，并探究了局部因子。结果表明，促性腺激素和类固醇具有刺激作用，但IGF1对抵抗素的表达和分泌具有抑制作用。抵抗素可降低促性腺激素和局部激素诱导的类固醇分泌，并抑制3β-羟基类固醇脱氢酶、17β-羟基类固醇脱氢酶和细胞色素P450芳香化酶的蛋白质表达。此外，我们证明抵抗素可增加孕酮和睾酮受体的表达。这些发现均表明，抵抗素的表达和功能受促性腺激素和卵巢卵泡产生的局部因子调节。
