Role of non-classical effects of testosterone and epitestosterone on AMH balance and testicular development parameters

Exploring the human chorionic gonadotropin induced steroid secretion profile of mouse Leydig tumor cell line 1 by a 20 steroid LC-MS/MS panel

The canonical androgen synthesis in Leydig cells involves Δ5 and Δ4 steroids. Besides, the backdoor pathway, eompassing 5α and 5α,3α steroids, is gaining interest in fetal and adult pathophysiology. Moreover, the role of androgen epimers and progesterone metabolites is still unknown. We developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for measuring 20 steroids and used it to investigate the steroid secretion induced by human chorionic gonadotropin (hCG) in the mouse Leydig tumor cell line 1 (mLTC1). Steroids were extracted from 500 µL supernatants from unstimulated or 100 pM hCG-exposed mLTC1 cells, separated on a Luna C8 100 × 3 mm, 3 µm column, with 100 µM NH4F and methanol as mobile phases, and analyzed by positive electrospray ionization and multiple reaction monitoring. Sensitivity ranged within 0.012-38.0 nmol/L. Intra-assay and inter-assay imprecision were < 9.1% and 10.0%, respectively. Trueness, recovery and matrix factor were within 93.4-122.0, 55.6-104.1 and 76.4-106.3%, respectively. Levels of 16OH-progesterone, 11-deoxycortisol, androstenedione, 11-deoxycorticosterone, testosterone, 17OH-progesterone, androstenedione, epitestosterone, dihydrotestosterone, progesterone, androsterone and 17OH-allopregnanolone were effectively measured. Traces of 17OH-dihydroprogesterone, androstanediol and dihydroprogesterone were found, whereas androstenediol, 17OH-pregnenolone, dehydroepiandrosterone, pregnenolone and allopregnanolone showed no peak. hCG induced an increase of 80.2-102.5 folds in 16OH-progesterone, androstenedione and testosterone, 16.6 in dihydrotestosterone, 12.2-27.5 in epitestosterone, progesterone and metabolites, 8.1 in 17OH-allopregnanolone and ≤ 3.3 in 5α and 5α,3α steroids. In conclusion, our LC-MS/MS method allows exploring the Leydig steroidogenesis flow according to multiple pathways. Beside the expected stimulation of the canonical pathway, hCG increased progesterone metabolism and, to a low extent, the backdoor route.

What Does Androgen Receptor Signaling Pathway in Sertoli Cells During Normal Spermatogenesis Tell Us?

Androgen receptor signaling pathway is necessary to complete spermatogenesis in testes. Difference between androgen binding location in Sertoli cell classifies androgen receptor signaling pathway into classical signaling pathway and non-classical signaling pathway. As the only somatic cell type in seminiferous tubule, Sertoli cells are under androgen receptor signaling pathway regulation via androgen receptor located in cytoplasm and plasma membrane. Androgen receptor signaling pathway is able to regulate biological processes in Sertoli cells as well as germ cells surrounded between Sertoli cells. Our review will summarize the major discoveries of androgen receptor signaling pathway in Sertoli cells and the paracrine action on germ cells. Androgen receptor signaling pathway regulates Sertoli cell proliferation and maturation, as well as maintain the integrity of blood-testis barrier formed between Sertoli cells. Also, Spermatogonia stem cells achieve a balance between self-renewal and differentiation under androgen receptor signaling regulation. Meiotic and post-meiotic processes including Sertoli cell - Spermatid attachment and Spermatid development are guaranteed by androgen receptor signaling until the final sperm release. This review also includes one disease related to androgen receptor signaling dysfunction named as androgen insensitivity syndrome. As a step further ahead, this review may be conducive to develop therapies which can cure impaired androgen receptor signaling in Sertoli cells.