Oral Presentation ESA-SRB-ANZBMS 2021

Detection of Designer Steroids Using Androgen Bioassays  (#111)

Alison K Heather 1
  1. Department of Physiology, School of Biomedical Sciences, University of Otago and InsituGen Ltd., Otago, New Zealand

Androgens remain the most widely abused prohibited substances in sports. Presently, detection of androgen abuse in sports relies on using gas chromatography-tandem mass spectrometry (GC-MS/MS)-based techniques. While exquisitely sensitive, these techniques are only as good as their reference libraries. If the library does not contain reference material for the targeted compound, the GC-MS/MS approach can fail. The failure of the GC-MS/MS approach is most apparent when designer androgens with novel structures are present and bypass targeted detection. Designer steroids are marketed as sports supplements, often with their true identity masked. Given that these novel structures need to be captured if anti-doping testing is going to be meaningful, a non-targeted catch-all approach for androgens is required. Androgen receptor-based bioassays represent a non-targeted approach that exploit the common androgen signaling pathway. The bioassays mimic biology whereby androgens activate AR, triggering the translocation of AR into the nucleus where AR binds to androgen response elements (ARE) in the genome to enhance expression of androgen response genes. Commonly, yeast- or mammalian cells are genetically modified to overexpress AR and to harbor a synthetic DNA transcript that encodes an ARE upstream of a reporter gene, which when expressed acts as a biosensor for androgens. Cell-based bioassays have been used to identify presence of designer steroids in athlete’s biological samples, as well as sports supplements. Cell-based bioassay execution is, however, challenging and can be both labor intensive and time consuming. For these reasons, cell-based bioassays are unlikely to be used as a screening approach for anti-doping laboratories despite their proven non-targeted approach. To overcome the complexity of cell-based androgen bioassays, cell-free androgen bioassays have recently emerged as a high-throughput screening option. Application of this new state-of-the-art methodology, complementary to the targeted screening approaches, will increase the chance of detecting designer androgens.