PDF(Pubmed)
Abstract：
Introduction: Doping and steroid use represent a serious threat to animal health and can even lead to their untimely and painful death. However, doping is an acute problem in today\'s animal racing world, particularly in camel racing. Testosterone and its ten esters (benzoate, valerate, isocaproate, hexahydrobenzoate, decanoate, undecanoate, laurate, enanthate, cypionate, and caproate) are of utmost importance, because when they are administered to animals it is difficult to measure them efficiently. The levels of testosterone and its esters in camels and other animals are typically determined using urine and blood tests. The aim of this study was to develop and validate a liquid chromatographic-mass spectrometric (LC-MS/MS) method to determine testosterone esters in camel hair, and to apply the validated method to determine testosterone esters in collected samples. To our knowledge, this is the first report of such research. Results and Discussion: The levels of testosterone and its ten derivatives, along with the cortisol-D4 internal standard, were optimised for LC-MS/MS analysis; however, only testosterone along with its seven esters (namely benzoate, valerate, isocaproate, hexahydrobenzoate, decanoate, undecanoate and laurate) could be validated in camel hair. Only five testosterone esters could be determined in camel hair samples; the concentrations were obtained as 10.5-14.9 pg/mg for valerate (in three camels), 12.5-151.6 pg/mg for hexahydrobenzoate (in six camels), 4.8-32.1 pg/mg for laurate (in five camels), 5.1 pg/mg decanoate (in one camel), and 8.35-169 pg/mg for testosterone (in all 24 camels). Interestingly, the three racing camels displayed high concentrations of testosterone (59.2-169 pg/mg, all three camels), laurate (4.8-14.5 pg/mg, two camels), hexahydrobenzoate (116 pg/mg, one camel), decanoate (5.1 pg/mg, one camel), and valerate (11.7 pg/mg, one camel). Methods: Camel hair samples were collected from 21 non-racing dromedary camels along with three racing camels in Al Ain, UAE; these were decontaminated, pulverised, sonicated, and extracted prior to analysis. An LC-MS/MS method was employed to determine the levels of testosterone esters in the hair samples. Conclusions: This novel camel-hair test procedure is accurate, sensitive, rapid, and robust. The findings reported in this study could be significant to evaluate racing camels for suspected doping offenses. Further controlled testosterone supplementation studies are required to evaluate individual esters\' effects on camel health and diseases and on performance enhancement levels. This new hair test could promote further studies in doping control, toxicology, and pharmacology, as well as having other clinical applications relating to camel health, injury, and disease.
摘要：
简介：兴奋剂和类固醇的使用对动物健康构成严重威胁，甚至可能导致其过早和痛苦的死亡。然而,兴奋剂是一个严重的问题，在今天的动物比赛世界，尤其是在骆驼比赛中。睾酮及其十酯（苯甲酸酯，戊酸盐，异己酸盐,六氢苯甲酸酯，癸酸,十一烷酸酯,月桂酸盐,庚酸盐,cypionate,和己酸盐)是最重要的，因为当它们被施用于动物时，很难有效地测量它们。通常使用尿液和血液测试来确定骆驼和其他动物中的睾丸激素及其酯的水平。本研究的目的是开发和验证液相色谱-质谱（LC-MS/MS）方法，以确定驼毛中的睾酮酯，并应用经验证的方法测定采集样品中的睾酮酯。据我们所知,这是此类研究的第一份报告。结果和讨论：睾酮及其十种衍生物的水平，连同皮质醇-D4内标,为LC-MS/MS分析进行了优化；然而，只有睾酮及其七种酯(即苯甲酸酯，戊酸盐，异己酸盐,六氢苯甲酸酯，癸酸,十一烷酸酯和月桂酸酯）可以在驼毛中得到验证。在骆驼头发样品中只能测定五种睾酮酯；戊酸酯的浓度为10.5-14.9pg/mg（在三头骆驼中），对于六氢苯甲酸酯（六头骆驼），12.5-151.6pg/mg，月桂酸盐（五头骆驼）4.8-32.1pg/mg，5.1pg/mg癸酸酯（在一只骆驼中），和8.35-169pg/mg的睾酮（在所有24头骆驼中）。有趣的是,三只赛马骆驼显示出高浓度的睾丸激素（59.2-169pg/mg，所有三只骆驼)，月桂酸盐（4.8-14.5pg/mg，两只骆驼)，六氢苯甲酸酯（116pg/mg，一只骆驼)，癸酸酯（5.1pg/mg，一只骆驼)，和戊酸（11.7pg/mg，一只骆驼）。方法：从AlAin的21头非赛车单峰骆驼和3头赛车骆驼中收集骆驼毛发样本，阿联酋；这些被净化了，粉碎，声处理,并在分析之前提取。采用LC-MS/MS方法测定毛发样品中睾酮酯的水平。结论：这种新颖的驼毛测试程序是准确的，敏感,快速,和强大的。这项研究报告的发现对于评估赛车骆驼的可疑兴奋剂罪行可能具有重要意义。需要进一步的受控睾酮补充研究，以评估个体酯对骆驼健康和疾病以及性能增强水平的影响。这项新的头发测试可以促进兴奋剂控制方面的进一步研究，毒理学,和药理学，以及其他与骆驼健康相关的临床应用，损伤,和疾病。
