Anjum Shabana, Krishna Amitabh, Tsutsui Kazuyoshi
Department of ZoologyBanaras Hindu University, Varanasi 221 005, Uttar Pradesh, IndiaDepartment of BiologyWaseda University, Tokyo 162-8480, Japan.
Department of ZoologyBanaras Hindu University, Varanasi 221 005, Uttar Pradesh, IndiaDepartment of BiologyWaseda University, Tokyo 162-8480, Japan
J Endocrinol. 2014 Oct;223(1):79-91. doi: 10.1530/JOE-14-0333. Epub 2014 Aug 19.
The aim of this study was to evaluate the effects of in vivo and in vitro treatments with RFamide-related peptide 3 (RFRP3), a mammalian gonadotropin-inhibitory hormone ortholog, on testicular activities, i.e. spermatogenesis and steroidogenesis, in mice. Mice were treated in vivo with different doses of RFRP3 (control: 0.02 μg, 0.2 μg, and 2.0 μg/day) for 8 days. For in vitro study, the testes of mice were evaluated with different doses of RFRP3 (control: 1 and 10 ng/ml) with or without LH (control: 10 and 100 ng/ml) for 24 h at 37 °C. RFRP3 treatment produced significant changes in the body mass, circulating steroid level, and testicular activity in mice. RFRP3 treatment also caused dose-dependent histological changes in spermatogenesis, such as decline in germ cell proliferation and survival markers and increase in apoptotic markers in testis. Both in vivo and in vitro studies showed the inhibitory effect of RFRP3 on testosterone synthesis in the testis. RFRP3 inhibited the expression of the receptor for LH (LHCGR), STAR protein, cytochrome P450 side-chain cleavage (CYP11A1) and 3β-hydroxysteroid dehydrogenase in the testis, and testosterone secretion dose dependently. This study also suggested that the inhibitory effect of RFRP3 in the testis may be mediated through local production of GnRH. Thus, RFRP3 inhibits testicular steroidogenesis and spermatogenesis either indirectly through GnRH or by directly influencing germ cell proliferation, survival, and apoptosis.
本研究旨在评估用RFamide相关肽3（RFRP3，一种哺乳动物促性腺激素抑制激素直系同源物）进行体内和体外处理对小鼠睾丸活动（即精子发生和类固醇生成）的影响。小鼠接受不同剂量的RFRP3体内处理（对照组：0.02μg、0.2μg和2.0μg/天），持续8天。对于体外研究，将小鼠睾丸用不同剂量的RFRP3（对照组：1和10ng/ml），在有或无促黄体生成素（对照组：10和100ng/ml）的情况下于37°C孵育24小时。RFRP3处理使小鼠的体重、循环类固醇水平和睾丸活动发生了显著变化。RFRP3处理还导致精子发生过程中出现剂量依赖性的组织学变化，如生殖细胞增殖和存活标志物下降以及睾丸中凋亡标志物增加。体内和体外研究均显示RFRP3对睾丸中睾酮合成有抑制作用。RFRP3剂量依赖性地抑制睾丸中促黄体生成素受体（LHCGR）、类固醇生成急性调节蛋白（STAR）、细胞色素P450侧链裂解酶（CYP11A1）和3β - 羟基类固醇脱氢酶的表达以及睾酮分泌。本研究还表明，RFRP3在睾丸中的抑制作用可能通过GnRH的局部产生介导。因此，RFRP3通过GnRH间接抑制睾丸类固醇生成和精子发生，或直接影响生殖细胞的增殖、存活和凋亡。
