Decoding 11-oxygenated androgen synthesis: insights from enzyme gene expression and LC-MS/MS quantification

Area of Science:

• Endocrinology
• Molecular Biology
• Human Physiology

Background:

• 11-oxygenated androgens, derived from adrenal and peripheral sources, are significant. However, their synthesis pathways, including involved organs and cell types, are not fully understood.
• Limited knowledge exists regarding the specific organs and cellular mechanisms responsible for producing 11-oxygenated androgens.

Purpose of the Study:

• To comprehensively map the expression profiles of enzyme-encoding genes involved in 11-oxygenated androgen synthesis across various human tissues.
• To identify the specific organs and cell types responsible for the synthesis of 11-oxygenated androgens in humans.
• To investigate age and sex-dependent variations in the expression of key enzymes in peripheral tissues.

Main Methods:

• Utilized bulk RNA sequencing (30 tissues), single-cell RNA sequencing (16 tissues), and proteomics (29 tissues) for comprehensive gene expression analysis.
• Employed immunohistochemistry and liquid chromatography-tandem mass spectrometry (LC-MS/MS) for validation and quantification of key metabolites.
• Developed the TransMap website for accessible visualization of transcriptome data.

Main Results:

• Elevated expression of HSD11B2 and AKR1C3 genes was observed in the kidney and intestines.
• Enzyme expression showed an increasing trend with age in women and a decreasing trend in men within these organs.
• Single-cell analysis localized HSD11B2 to kidney collecting duct principal cells and AKR1C3 to proximal tubules; nearly all intestinal epithelial cells expressed these enzymes.
• The kidney had the highest levels of 11-ketoandrostenedione (11KA4) and 11-ketotestosterone (11KT); the intestine also showed substantial synthesis of these androgens.
• A comprehensive transcriptome visualization tool, TransMap, was created.

Conclusions:

• This research provides a detailed overview of 11-oxygenated androgen synthesis in peripheral tissues, particularly the kidney and intestines.
• The findings highlight the potential roles of these androgens in human physiology, with implications for understanding tissue-specific androgen activity.
• The study establishes a foundation for further research into the biological significance and potential clinical relevance of 11-oxygenated androgens.