Introduction

The two major androgens in humans are testosterone (T) and dihydrotestosterone (DHT). DHT is produced via the classical, backdoor, and alternative steroidogenic pathways. In addition, recent studies have identified C11-oxy C₁₉ steroids as novel human androgens. Although the placenta is known to be involved in steroid metabolism, androgen levels in full-term placentas have poorly been investigated.

Subjects and methods

Ten placentas of healthy full-term neonates (five males and five females) were examined. We quantified progesterone, androstenedione (A4), T, allopregnanolone, androsterone, and estradiol, as well as four C11-oxy androgens (11β-hydroxyandrostenedione, 11β-hydroxytestosterone, 11-ketoandrostenedione (11KA4), and 11-ketotestosterone (11KT)), using liquid chromatography-tandem mass spectrometry.

Results

In all samples, levels of the ten steroids were above the detection limit. Progesterone was by far most abundant, while levels of T and androsterone were relatively low. Levels of 11KT and 11KA4 were higher than those of T and A4, respectively. There were no differences in steroid levels between male and female samples.

Discussion

This study demonstrates that full-term placentas contain several steroids in the classical, backdoor, and alternative pathways. Placentas are likely to function as the supplier of progesterone to other steroidogenic tissues. More importantly, we found that placentas comprise relatively large amounts of 11KA4 and 11KT, which may be produced through steroid transfer from the adrenal gland or from the maternal circulation. These results indicate that the placenta participates in a feto-maternal multi-organ network for androgen biosynthesis.

中文翻译：

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足月人胎盘中雄激素及其前体的定量

介绍

人体中的两种主要雄激素是睾酮 (T) 和二氢睾酮 (DHT)。DHT 是通过经典、后门和替代类固醇生成途径产生的。此外，最近的研究已将 C11-oxy C ₁₉类固醇确定为新型人类雄激素。尽管已知胎盘参与类固醇代谢，但对足月胎盘中的雄激素水平的研究却很少。

主题和方法

检查了十个健康足月新生儿（五男五女）的胎盘。我们量化了黄体酮、雄烯二酮 (A4)、T、别孕酮、雄酮和雌二醇，以及四种 C11-氧雄激素（11β-羟基雄烯二酮、11β-羟基睾酮、11-酮雄烯二酮 (11KA4) 和 11-酮睾酮 (11KT)） ，使用液相色谱-串联质谱法。

结果

在所有样品中，十种类固醇的含量均高于检测限。黄体酮是迄今为止最丰富的，而 T 和雄酮水平相对较低。11KT 和 11KA4 的水平分别高于 T 和 A4。男性和女性样本之间的类固醇水平没有差异。

讨论

这项研究表明，足月胎盘在经典、后门和替代途径中含有几种类固醇。胎盘可能作为其他类固醇生成组织的孕酮供应商。更重要的是，我们发现胎盘包含相对大量的 11KA4 和 11KT，这可能是通过从肾上腺或母体循环中转移类固醇产生的。这些结果表明胎盘参与了用于雄激素生物合成的胎儿-母体多器官网络。