Influence of Saw palmetto and Pygeum africana extracts on the urinary concentrations of endogenous anabolic steroids: Relevance to doping analysis

Abstract

BackgroundOver the counter preparations containing Saw palmetto and Pygeum africana extracts are commonly used in the treatment of benign prostatic hyperplasia with lower urinary tract symptoms. Their effects are likely due to their anti-androgenic activity, involving the interaction with type 1 and type 2 isoenzymes of the 5α-reductase family. Hypothesis/purposeFor effects similar to the above, the inhibitors of 5α-reductase (e.g., finasteride) are classified as confounding factors in the evaluation of the urinary steroid profile in sport doping. We aimed to verify whether the oral intake of products containing Saw palmetto and Pygeum africana could affect the urinary concentration of a series of steroids, not limited to those included in the “steroidal module” of the Athlete Biological Passport (ABP). Study designWe have followed the effects of a five-day administration of Saw palmetto (320 mg) and Pygeum africana (100 mg) to three non-smokers male subjects on the urinary parameters constituting the “steroidal module” of the ABP, and on the concentration of additional steroid markers. In parallel, we have also measured the urinary concentration of β-sitosterol, which is the active component of Saw palmetto and Pygeum Africana. MethodsSample collection was performed five days before starting the controlled administration study to obtain the baseline urinary steroid pattern for each subject. After this period, the three volunteers took a dose of Saw palmetto (320 mg) and Pygeum africana (100 mg) formulation orally, once a day, for five consecutive days. Urine samples were collected at different times of the day and stored at −20 °C until analysis. Samples were analyzed by a previously developed and validated method based on gas chromatography coupled to tandem mass spectrometry (GC–MS/MS). ResultsOur results show that the intake of a single oral dose of Saw palmetto and Pygeum africana for five consecutive days leads to a broader data dispersion of the target steroids' concentration levels, and, consequently, to a variation of the corresponding individual normality ranges. ConclusionThe intake of dietary supplements containing Saw palmetto and Pygeum africana could be a source of interference in the correct longitudinal evaluation of the individual steroid profile, as described in the framework of ABP. We believe their urinary levels should be monitored as it is presently done for other confounding factors of the steroidal module of the ABP.