Developmental Changes in Human Fetal Testicular Cell Numbers and Messenger Ribonucleic Acid Levels during the Second Trimester
Open Access
- 1 December 2007
- journal article
- other
- Published by The Endocrine Society in Journal of Clinical Endocrinology & Metabolism
- Vol. 92 (12), 4792-4801
- https://doi.org/10.1210/jc.2007-1690
Abstract
Context: Normal fetal testis development is essential for masculinization and subsequent adult fertility. The second trimester is a critical period of human testicular development and masculinization, but there is a paucity of reliable developmental data. Objective: The objective of the study was to analyze second-trimester human testicular morphology and function. Design: This was an observational study of second-trimester testis development. Setting: The study was conducted at the Universities of Glasgow and Aberdeen. Patients/Participants: Testes were collected from 57 morphologically normal fetuses of women undergoing elective termination of normally progressing pregnancies (11–19 wk gestation). Main Outcome Measure(s): Testicular morphology, cell numbers, and quantitative expression of 22 key testicular genes were determined. Results: Sertoli cell and germ cell number increased exponentially throughout the second trimester. Leydig cell number initially increased exponentially but slowed toward 19 wk. Transcripts encoding Sertoli (KITL, FGF9, SOX9, FSHR, WT1) and germ (CKIT, TFAP2C) cell-specific products increased per testis through the second trimester, but expression per cell was static apart from TFAP2C, which declined. Leydig cell transcripts (HSD17B3, CYP11A1, PTC1, CYP17, LHR, INSL3) also remained static per cell. Testicular expression of adrenal transcripts MC2R, CYP11B1, and CYP21 was detectable but unchanged. Expression of other transcripts known or postulated to be involved in testicular development (GATA4, GATA6, CXORF6, WNT2B, WNT4, WNT5A) increased significantly per testis during the second trimester. Conclusions: The second trimester is essential for the establishment of Sertoli and germ cell numbers. Sertoli and Leydig cells are active throughout the period, but there is no evidence of changing transcript levels.Keywords
This publication has 52 references indexed in Scilit:
- Expression of Cyp21a1 and Cyp11b1 in the fetal mouse testisReproduction, 2007
- GATA‐4 is required for sex steroidogenic cell development in the fetal mouseDevelopmental Dynamics, 2006
- Identification of a novel population of adrenal-like cells in the mammalian testisDevelopmental Biology, 2006
- Fgf9 and Wnt4 Act as Antagonistic Signals to Regulate Mammalian Sex DeterminationPLoS Biology, 2006
- In humans, early cortisol biosynthesis provides a mechanism to safeguard female sexual developmentJCI Insight, 2006
- Gene Expression in Rat Leydig Cells During Development from the Progenitor to Adult Stage: A Cluster Analysis1Biology of Reproduction, 2005
- Wnt4 is required for proper male as well as female sexual developmentDevelopmental Biology, 2004
- Development of the Human Fetal TestisPediatric Pathology & Laboratory Medicine, 1996
- A review of recent advances in stereology for quantifying neural structureJournal of Neurocytology, 1992
- Proliferation of Sertoli cells during development of the human testis assessed by stereological methodsInternational Journal of Andrology, 1987