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Growth Hormone Secretagogues in Anti-Doping

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Growth Hormone Secretagogues in Anti-Doping POMPEU FABRA UNIVERSITY Department of Experimental and Health Sciences ASSESSMENT OF GROWTH HORMONE SECRETAGOGUES IN ANTI-DOPING PhD thesis Armand Pinyot Comelles Neurosciences Research Programme Municipal Institute of Medical Research IMIM-Institut Hospital del Mar d’investigacions Mèdiques Barcelona, July 2012 POMPEU FABRA UNIVERSITY Department of Experimental and Health Sciences Doctoral Programme: Health and Life Sciences ASSESSMENT OF GROWTH HORMONE SECRETAGOGUES IN ANTI-DOPING Memòria presentada per Armand Pinyot Comelles per a optar al títol de Doctor per la Universitat Pompeu Fabra. Aquesta tesis ha estat realitzada sota la codirecció del Dr. Jordi Segura Noguera i el Dr. Ricardo Gutiérrez Gallego, en el grup d’Investigació en Bioanàlisi i Serveis Analítics, programa de Neurociències de l’IMIM-Institut Hospital del Mar d’Investigacions Mèdiques. Programa de Doctorat en Ciències de la Salut i de la Vida de la Universitat Pompeu Fabra. Dr Jordi Segura Dr Ricardo Gutiérrez Armand Pinyot Noguera Gallego Comelles Director de tesis Director de tesis Doctorand Barcelona, Juliol 2012 Agraïments / Acknowledgements Em disposo a presentar la meva tesi. Tot i el temps que fa que somio en poder pronunciar aquestes paraules, ara que va de debò, resulta que són completament falses. Efectivament, la tesi va al meu nom però seria impossible haver-la realitzat sense un llarg reguitzell de gent que m’ha proporcionat el seu suport, ja sigui científic, moral o simplement estant al meu costat un dia en el que no han sortit bé els experiments. Creieu-me si us dic que podria escriure diverses pàgines d’agraïments però resulta que la tesi tracta un altre tema i així, en aquest petit apartat, m’agradaria fer esment a algunes de les moltes persones de les que us parlo. En primer lloc, d’aquesta tesi no n’existiria ni una paraula si no fos gràcies al Dr. Jordi Segura. Vull agrair-li profundament que em donés l’oportunitat d’entrar de la seva mà al món de la recerca científica, gràcies per la direcció de la tesi, per les correccions, pels consells i critiques sempre constructives. És un plaer poder treballar amb algú del seu talent i experiència. Espero de tot cor haver complert amb les expectatives dipositades en mi a l’inici del doctorat. Gràcies al Dr. Ricardo Gutiérrez per la codirecció. El Dr. Ricardo Gutiérrez, ha estat per mi un inestimable guia del fosc túnel en el que es pot convertir la recerca després d’una temporada de mals resultats. He aprés tantes coses d’ell que és complicat triar-ne una de sola però la més encertada seria el rigor, ja sigui experimental com literari. Moltes gràcies per les incomptables hores dedicades a les correccions provisionals, a la ingent quantitat de e-mails intercanviats per tal que aquesta tesi sigui el que és. Degut a l’elevat nombre d’hores conviscudes, puc afirmar que a part d’un formidable director de tesi, ha resultat una gran persona i a més, un bon amic. Voldria també agrair als altres components del grup GHS. Al Dr. Zoran Nikolovski per creure que jo podria portar a bon port aquest projecte quan encara ni tant sols havia acabat la carrera. Tot i que hem discutit més que no pas treballat, sé que m’emporto un amic. Sóc conscient que el teu afany per treure’m de polleguera, qüestionar tot el que deia o feia, era senzillament per fer-me créixer com a persona i com a científic. Agrair també al Dr. Jaume Bosch per les incomptables hores de xerrameca científica, per donar-me tot el seu suport en infinitat de situacions i per il·luminar-me amb el seu coneixement en termes de ciència, de la vida en general i dels mots encreuats en particular. Fent memòria de la gran quantitat d’hores passades dins les parets de l’IMIM, em venen munts d’imatges d’un grup d’amics que s’ho passava de conya mentre treballava. Crec que vam aconseguir crear un grup capaç de fer més esport de forma conjunta que cadascú per separat, confeccionant moments memorables dels quals m’aprofitaré per anar agraint individualment. Gràcies Josep, Quim i Raúl pel moment èpic de pujar tots en el segon calaix d’un podi mentre al primer lloc hi havia un nen de sis anys. Gràcies de forma individual al Quim per haver de baixar cames ajudeu- me del cim de l’Aneto. Gràcies al Toni per la més gran demostració de superació després de pujar i baixar del Mont Perdut amb unes hamburgueses als talons. Gràcies a la Mito i la Civit per demostrar que és pràcticament impossible controlar un caiac si aquest està del revés. Gràcies a la Beth per les lliçons magistrals de basquet i sobretot per aquelles pilotes de voleibol xutades amb ràbia. Perdó a la Carmen per la infinitat de pilotades que va rebre, juro que de forma totalment involuntària, en diversos partits de voleibol, bàsquet o futbol, en aquest apartat també es pot afegir l’Ester, que en un partit de bàsquet va quedar grogui després un xoc, tothom sospita que voluntari, amb el Gerard. Ah, el Gerard, mestre de mestres, gran mag del caos, l’il·lusionista de S-ants (si, si, així, separat), gràcies per l’esport de més alt risc que és intentar desxifrar algun dels teus correus. A tots vosaltres, esportistes d’elit frustrats, mil gràcies. Em trobo en la obligació moral d’agrair aquesta tesi a tres grans amics, al Juanjo, al Pep i al Salva. Segurament per motius completament diferents l’un de l’altre però que sense la suma dels tres aquesta tesi no hauria estat possible. En aquests anys a l’IMIM, a part d’una gran quantitat d’amics, he trobat també algú amb qui compartir molt més que esports accidentats (que també). Algú amb qui compartir el dia a dia i els dies que vindran. Gràcies Cris, per fer que tot el que m’envolta tingui sentit. Per acabar, m’agradaria agrair a la meva família, als meus pares, al meu germà, la Clàudia, la Laura i el Marc i la Cris pel suport que sempre he rebut i per ser uns referents modèlics. M’agradaria dedicar-vos aquesta tesi ja que és, en la major part, vostra. Abstract The presented doctoral thesis describes de development of a new analytical method in anti-doping. At present, the detection of recombinant growth hormone abuse is relatively settled, and therefore it is anticipated that growth hormone secretagogues (GHS) will replace GH, as they can induce similar anabolic effects. The aim of this thesis is the detection of growth hormone secretagogues (GHS) from urine samples. GHS presents high structural diversity rendering very difficult a single conventional chemical determination for all. Thus, in this approach the single feature shared by all GHS, interaction with the specific receptor GHS-R1a, is targeted using a method based on a competitive assay against a labelled ligand. By monitoring the signal of the labelled ligand at the end of the test, the presence of any GHS in the sample can be determined. A threshold value below which a sample is considered suspicious with low probability of being false positive was set up. The developed methodology was tested with 8 different GHS, and also samples from an administration assay of one of the GHS. Variables such as age, gender or physical exercise do not interfere with the method, which is currently under validation. Resum La present tesis doctoral desenvolupa una nova metodologia analítica antidopatge. Degut a que actualment la detecció de l'abús d'hormona del creixement recombinant està relativament resolta, es tem que els secretagogs de la hormona del creixement (GHS) siguin el relleu natural ja que es creu provoquen efectes anabòlics semblants. L'objectiu de la tesi és la detecció de secretagogs de l'hormona del creixement (GHS) a partir de mostres d’orina. Els GHS presenten gran diversitat estructural que fa difícil una única determinació química convencional. Per això s'ha optat per utilitzar la seva propietat comú d'interaccionar amb el receptor específic GHS-R1a, mitjançant un mètode basat en un assaig competitiu front un lligand marcat. Monitorant la senyal del lligand marcat al final de l’assaig es pot determinar la presència de qualsevol GHS a la mostra. S'ha determinat per l’assaig un valor de tall de la senyal del lligand marcat per sota de la qual una mostra és considerada sospitosa amb una baixa probabilitat d'obtenir un fals positiu. El mètode desenvolupat ha funcionat amb els 8 GHS estudiats, incloses mostres reals procedents d'un assaig d’administració d’un d’ells. Variables com l'edat, gènere o exercici físic no provoquen interferències en el mètode, que actualment es troba en fase de validació. Abbreviations 125I Iodine 125 Ala Alanine AMP Adenosine monophosphate Bmax Receptor density cAMP Cyclic adenosine monophosphate CHO Chinese hamster ovary cell CS-A Chorionic somatomammotropin-A CS-B Chorionic somatomammotropin-B CS-L Chorionic somatomammotropin-like CV Coefficient of variation Cy5 Cyanine D Concentration of labelled ligand Da Daltons DELFIA Dissociation-enhanced lanthanide fluorescent immunoassay DMEM Dulbecco's modified Eagle medium DMSO Dimethyl sulfoxide EPO Erythropoietin FAM Carboxyfluorescein FBS Foetal bovine serum FITC Fluorescein isothiocyanate fmol Femtomol FRET Fluorescence resonance energy transfer GHBP Growth hormone binding protein GHIH Growth hormone inhibiting hormone GHRH Growth hormone releasing hormone GHRH-R Growth hormone releasing hormone receptor GHRP GH-releasing peptide GHS Growth hormone secretagogue GHS-R1a Growth hormone secretagogue variant 1a GHS-R1b Growth hormone secretagogue variant 1b Gly Glycine Glu Glutamic acid GOAT Ghrelin O-acyltransferase h Hour HEK Human embryonic kidney hGH Human growth hormone hGH-N Growth hormone-normal hGH-V Growth hormone-variant His Histidine HPLC High-performance liquid chromatography IC50 Half maximal inhibitory concentration IGFBP Insulin-like growth factor binding protein IGF-I Insulin-like growth factor I Kd Equilibrium dissociation constant of the labelled drug.
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