Revealing the influence of glucocorticoid treatment on the excretion of anabolic-androgenic steroids in horses through in vitro digestive simulations and an in vivo case study.

This research investigates the effect of glucocorticoid treatment, a common anti-inflammatory therapy, on the excretion of anabolic-androgenic steroids (AAS) in horses. The study confirms that treatment disrupts AAS synthesis and excretion, not via direct digestion transformation, but likely through impacts on the hypothalamic-pituitary-adrenal axis.

Overview

The study endeavours to explore the potential correlation between glucocorticoid treatment and the excretion of AAS in horses. Anabolic-androgenic steroids are banned in equestrian sports due to their enhancement effects on muscle growth and performance. However, they’ve been detected in some horses – that haven’t been treated with AAS – implying a possible role of glucocorticoids, which are related to AAS structurally and used for anti-inflammatory therapy, in this phenomenon.

In vivo and In vitro Exploration

• The researchers studied the influence of glucocorticoid treatment on AAS excretion both in vitro (through simulated digestion) and in vivo (using a treated gelding).

Analytical Techniques

• They utilized UHPLC-MS/MS and UHPLC-Orbitrap-HRMS methods for analysis of the urine and in vitro digestion samples.

Findings

• The treatment resulted in a significant influence on the urinary excretion of α-testosterone, β-testosterone, and androsta-1,4-diene-3,17-dione (ADD).
• Post-treatment, αT-concentrations were detected up to 20ng/mL and ADD, not present pre-treatment, could be detected.
• Levels of cortisone and cortisol also increased markedly between days 37 and 48 post-treatment.

Conclusion

• Despite the in vitro digestion results ruling out direct biotransformation of glucocorticoids to AAS by the microbiota of the equine hindgut, the study confirmed a disruption to the synthesis and excretion of AAS through glucocorticoid treatment.
• This disruption is likely not caused by direct gastrointestinal digestion transformation, but rather by influencing the hypothalamic-pituitary-adrenal axis.