Monitoring the endogenous steroid profile disruption in urine and blood upon nandrolone administration: An efficient and innovative strategy to screen for nandrolone abuse in entire male horses.

The research article presents a new method for identifying the misuse of a commonly abused steroid, nandrolone, in male horses. By monitoring variations in the endogenous steroid profile in horse urine and blood, this method enables more efficient and accurate detection of nandrolone abuse in horses.

Research Background

• The paper primarily deals with nandrolone, a widely abused endogenous steroid hormone in male horses. It’s hard to detect due to its endogenous presence.
• Under current international standards, the misuse of nandrolone is determined based on the urinary concentration ratio of 5α-estrane-3β,17α-diol (EAD) to 5(10)-estrene-3β,17α-diol (EED).
• However, this method can be inaccurate due to intra- and inter-variability; the variance of endogenous steroids levels within a single horse and between different horses respectively.

New Analytical Strategy

• In response to this problem, the researchers developed a new approach to detect nandrolone misuse. They profiled the endogenous steroids in horses that were given nandrolone and in those that weren’t.
• Their experiment involved collecting plasma and urine samples from a horse administered with nandrolone laurate over three months, and from seven non-treated horses over a year.
• To analyze these samples, the researchers developed a multi-stage process. This included methanolysis, liquid-liquid and solid-phase extractions, derivatization, and gas chromatography-tandem mass spectrometry (GC-MS/MS) for quantification.

Significant Findings

• The data collected allowed researchers to develop statistical models that can separate control samples from those collected post-administration.
• These same models proved successful in predicting the compliance status of samples collected from racing horses, thus demonstrating the efficiency and robustness of this new detection method.

In summary, this research introduces an innovative and efficient method to detect nandrolone misuse in male horses, which could significantly improve anti-doping measures in equine sports.