Detection and identification of ACP-105 and its metabolites in equine urine using LC/MS/MS after oral administration.

ACP-105 is a novel nonsteroidal selective androgen receptor modulator (SARM) with a tissue-specific agonist effect and does not have side effects associated with the use of common androgens. This research reports a comprehensive study for the detection of ACP-105 and its metabolites in racehorses after oral administration (in vivo) and postulating its structures using mass spectrometric techniques. To obtain the metabolic profile of ACP-105, a selective and reliable LC-MS/MS method was developed. The chemical structures of the metabolites were determined based on their fragmentation pattern, accurate mass, and retention time. Under the current experimental condition, a total of 19 metabolites were detected in ACP-105 drug administered equine urine samples. The study results suggest the following: (1) ACP-105 is prone to oxidation, which gives corresponding monohydroxylated, dihydroxylated, and trihydroxylated metabolites; (2) along with oxidation, there is a possibility of elimination of water molecule (dehydration) from the third position of the tropine moiety, resulting in the dehydrated analogs of corresponding monohydroxylated, dihydroxylated, and trihydroxylated metabolites; (3) from the study on the metabolites using LC-MS/MS, it is clear that the fragmentation pattern is identical and a great number of fragment ions are common in all the metabolites and the parent drug. (4) The ACP-105 and its metabolites were detected for up to 72 h; thus, the result is a valuable tool for evaluating its use and/or misuse in sport.

Using Inductively Coupled Plasma Mass Spectrometry to Assess Essential and Performance-Enhancing Metals in the Urine of Racehorses.

Recently, an increased tendency to use various metals has been observed in the sports competition fields. Many of these metals and their organic complexes reportedly have good pharmacologic, therapeutic and performance-enhancement uses; they are banned or recommended as controlled medications in competitive sports. The objective of this research was to determine the concentration of pharmacologically relevant metals in urine samples collected from racehorses at various sport events, develop a method and assess the concentrations of above metals using inductively coupled plasma mass spectrometry (ICP-MS). Seven alkali-alkaline earth metals (lithium, sodium, potassium, magnesium, calcium, strontium and barium) and six heavy metals (chromium, cobalt, copper, zinc, arsenic and selenium) were studied in detail. To compare and confirm the concentrations of these metals, the screening was carried out on the basis of region and sex of the animal. ICP-MS provides extremely high sensitivity that enables the determination of the metals at very low concentration from complex biological matrices. From the research, it is clear that irrespective of sex and region the concentration of metal is very high in some samples, might be accidental or intentional doping to improve sporting performances. This research work is of significant importance in setting threshold values for screening metals in race day samples in order to avoid potential harmful effects on athletes and the depth of malpractices, it can bring to sports.