Clenbuterol detection for doping control
Usually, doping analyses are carried out in urine and blood samples. In contrast, hairs are not suitable as an alternative for screening purposes, because only specific substances are incorporated into hair, and in- and out-of-competition periods are not definable. In general, hair analysis is a target analysis on a limited number of substances (see Service>Hair analysis).
However, in exceptional cases hair analysis can be useful in doping control of athletes as well. The main advantage of hair compared to blood and urine samples is the possibility of a long-term detection. Therefore, the analysis may provide additional information, e.g. regarding a previous positive finding in urine.
The detection method on clenbuterol in hair is part of the accredited scope of the IDAS since 2004. In a current study, the applicability of the procedure to distinguish between a low-dose uptake of clenbuterol (e.g. by food), and a fraudulent abuse should be investigated utilizing hair samples. The project focuses on the interpretation of the findings in hair regarding frequency and time of exposure, with respect to influencing parameters (e.g. hair color).
Results from an application study
[Schlupp A, Anielski P, Thieme D, Müller RK, Meyer H, Ellendorff F. The beta-agonist clenbuterol in mane and tail hair of horses. Equine Vet J. 2004 Mar;36(2):118-22.]
Corticosteroids as biomarkers for stress
Cortisol and cortisone are endogenous produced corticosteroids. Beside the circadian fluctuation of biosynthesis, several circumstance connected with an increased production are known, e.g. chronic stress, depression and pregnancy. Circadian variations make interpretation of blood values difficult, but however would not affect concentrations in hair. In literature, hair concentration of cortisol has been discussed as a suitable marker for clinical diagnostics. In these studies, concentrations were measured using immunochemical methods in general.
Our investigations aim at the development of a high-sensitive and selective LC-MS/MS-detection method for quantification of corticosteroids in hair. Analysis of endogenous corticosteroids shall reveal biochemical relations in case of diseases (enzyme deficiencies) and stress responses. Furthermore, parameters and mechanisms important for the long-term detection and interpretation of findings in hair have to be investigated (e.g. incorporation, stability of analytes).
Endocannabinoids as biomarkers for stress
The endogenous excretion of endocannabinoids (e.g. anandamide), is another physiological system for regulation of physical or mental stress. Due to its interaction with the biosynthesis of corticosteroids during stress response, the endocannabinoid system will be investigated in parallel.
Detection of synthetic corticosteroids in hair
Additionally, synthetic corticosteroids shall be integrated in the method for endogenous glucocorticoids. In particular, the issue might be relevant for doping control of sports horses as well as to detect cheating in horse breeding.