Department of Biochemistry, I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry of Russian Academy of Sciences, 194223 Saint Petersburg, Russia.
Department of Bioinformatics and Medicinal Chemistry, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia.
Int J Mol Sci. 2020 Oct 11;21(20):7493. doi: 10.3390/ijms21207493.
Low-molecular-weight agonists of luteinizing hormone (LH)/human chorionic gonadotropin (hCG) receptor (LHCGR), which interact with LHCGR transmembrane allosteric site and, in comparison with gonadotropins, more selectively activate intracellular effectors, are currently being developed. Meanwhile, their effects on testicular steroidogenesis have not been studied. The purpose of this work is to perform a comparative study of the effects of 5-amino---butyl-4-(3-(1-methylpyrazole-4-carboxamido)phenyl)-2-(methylthio)thieno[2,3-] pyrimidine-6-carboxamide (TP4/2), a LHCGR allosteric agonist developed by us, and hCG on adenylyl cyclase activity in rat testicular membranes, testosterone levels, testicular steroidogenesis and spermatogenesis in young (four-month-old), aging (18-month-old) and diabetic male Wistar rats. Type 1 diabetes was caused by a single streptozotocin (50 mg/kg) injection. TP4/2 (20 mg/kg/day) and hCG (20 IU/rat/day) were administered for 5 days. TP4/2 was less effective in adenylyl cyclase stimulation and ability to activate steroidogenesis when administered once into rats. On the 3rd-5th day, TP4/2 and hCG steroidogenic effects in young adult, aging and diabetic rats were comparable. Unlike hCG, TP4/2 did not inhibit LHCGR gene expression and did not hyperstimulate the testicular steroidogenesis system, moderately increasing steroidogenic proteins gene expression and testosterone production. In aging and diabetic testes, TP4/2 improved spermatogenesis. Thus, during five-day administration, TP4/2 steadily stimulates testicular steroidogenesis, and can be used to prevent androgen deficiency in aging and diabetes.
促黄体激素（LH）/人绒毛膜促性腺激素（hCG）受体（LHCGR）的低分子量激动剂与 LHCGR 跨膜变构位点相互作用，与促性腺激素相比，更选择性地激活细胞内效应器，目前正在开发中。与此同时，它们对睾丸类固醇生成的影响尚未得到研究。本工作的目的是比较我们开发的 LHCGR 变构激动剂 5-氨基-4-(3-(1-甲基吡唑-4-羧酰胺基)苯基)-2-(甲硫基)噻吩[2,3-]嘧啶-6-甲酰胺（TP4/2）和 hCG 对大鼠睾丸膜中腺苷酸环化酶活性、睾酮水平、睾丸类固醇生成和年轻（四个月大）、衰老（18 个月大）和糖尿病雄性 Wistar 大鼠精子发生的影响。1 型糖尿病由单次链脲佐菌素（50mg/kg）注射引起。TP4/2（20mg/kg/天）和 hCG（20IU/大鼠/天）给药 5 天。TP4/2 单次给药对大鼠腺苷酸环化酶刺激和激活类固醇生成的能力的作用较小。在第 3-5 天，TP4/2 和 hCG 在年轻成年、衰老和糖尿病大鼠中的类固醇生成作用相当。与 hCG 不同，TP4/2 不会抑制 LHCGR 基因表达，也不会过度刺激睾丸类固醇生成系统，而是适度增加类固醇生成蛋白基因表达和睾酮产生。在衰老和糖尿病睾丸中，TP4/2 改善了精子发生。因此，在五天给药期间，TP4/2 可稳定地刺激睾丸类固醇生成，可用于预防衰老和糖尿病中的雄激素缺乏。
