Novel serum protein biomarkers indicative of growth hormone doping in healthy human subjects

The detection of recombinant human growth hormone (rhGH) is difficult due to its short half-life; therefore, novel and robust biomarkers of rhGH abuse are needed. In this study, serum samples derived from subjects treated with rhGH in a randomized, double blind, placebo-controlled crossover study were analyzed by 2-DE coupled with MS. Eight healthy male subjects aged 23.2 ± 0.6 yr were injected with rhGH (2 mg/day) or saline for 7 days with serum samples drawn at days 0, 3, and 8. Protein intensities were quantified and analyzed for differences between rhGH versus placebo treatments. Protein that showed significant changes were identified and confirmed by Western blotting. These included specific isoforms of alpha-1 antitrypsin and transthyretin that increased; and inter-alpha-trypsin inhibitor heavy chain H4, apolipoprotein A-1 and hemoglobin beta chain that decreased. These proteins represent novel biomarkers of short-term rhGH exposure and may lead to a new method for detecting rhGH doping.