Rapid investigating of phase I metabolites of SR9009 in vitro horse liver microsomes via feature-based molecular networking approach: Potential applications in doping control.

The research focused on unveiling new metabolites of SR9009, a substance banned in horseracing, through the application of a highly innovative technology known as feature-based molecular networking (FBMN) in horse liver microsomes. The findings of this study would benefit the forensic and anti-doping fields in achieving accurate and efficient detection.

Objective of the Research

• The primary aim of the study was to identify the phase I metabolites of SR9009, a peroxisome proliferator-activated receptor δ (PPARδ) agonist, in horse liver in vitro assay using feature-based molecular networking. Another critical goal was to establish a metabolic pathway of SR9009.

Issues with SR9009

• The USFDA did not approve SR9009 due to its potential benefits in energy homeostasis. Its illegal distribution has raised considerable concerns, forcing the World Anti-Doping Agency and the International Federation of Horseracing Authorities (IFHA) to list it as a prohibited substance. Therefore, there is a high need to identify its metabolites for doping control.

Relevance of Feature-based Molecular Networking

• The research utilizes an advanced analytical technique, the feature-based molecular networking (FBMN), which is superior to conventional methodologies in forensic science. It helps in identifying the mass spectra connectivity and, as such, helps identify undiscovered metabolites of SR9009 efficiently and accurately.

Findings

• The FBMN analysis revealed 15 metabolites of SR9009, including a new major N-dealkylated metabolite (-CHNOS). It indicates diverse metabolic modifications in horse liver microsome incubation assay.
• The study also sketched an in vitro metabolic pathway of SR9009 which consisted of several pathways such as hydroxylation, dehydrogenation, N-dealkylation dihydroxylation, etc. and their combinations.

Conclusion

• This research provided a deep understanding of SR9009 metabolism in horses and brought attention to the importance of using advanced analytical techniques for more precise and effective metabolite analysis needed for forensic and doping control functions.