RT Journal Article T1 Urinary sulphatoxymelatonin as a biomarker of serotonin status in biogenic amine-deficient patients. A1 Batllori, Marta A1 Molero-Luis, Marta A1 Arrabal, Luisa A1 Heras, Javier de Las A1 Fernandez-Ramos, Joaquin-Alejandro A1 Gutierrez-Solana, Luis Gonzalez A1 Ibañez-Mico, Salvador A1 Domingo, Rosario A1 Campistol, Jaume A1 Ormazabal, Aida A1 Sedel, Frederic A1 Opladen, Thomas A1 Zouvelou, Basiliki A1 Pons, Roser A1 Garcia-Cazorla, Angels A1 Lopez-Laso, Eduardo A1 Artuch, Rafael K1 Metabolism, inborn errors K1 Middle aged K1 Reference values K1 Serotonin K1 Young adult AB Melatonin is synthesized from serotonin and it is excreted as sulphatoxymelatonin in urine. We aim to evaluate urinary sulphatoxymelatonin as a biomarker of brain serotonin status in a cohort of patients with mutations in genes related to serotonin biosynthesis. We analized urinary sulphatoxymelatonin from 65 healthy subjects and from 28 patients with genetic defects. A total of 18 patients were studied: 14 with autosomal dominant and recessive guanosine triphosphate cyclohydrolase-I deficiency; 3 with sepiapterin reductase deficiency; and 1 with aromatic L-amino acid decarboxylase deficiency. Further 11 patients were studied after receiving serotoninergic treatment (serotonin precursors, monoamine oxidase inhibitors, selective serotonin re-uptake inhibitors): 5 with aromatic L-amino acid decarboxylase deficiency; 1 with sepiapterin reductase deficiency; 3 with dihydropteridine reductase deficiency; and 2 with 6-pyruvoyltetrahydropterin synthase deficiency. Among the patients without therapy, 6 presented low urinary sulphatoxymelatonin values, while most of the patients with guanosine triphosphate cyclohydrolase-I deficiency showed normal values. 5 of 11 patients under treatment presented low urine sulphatoxymelatonin values. Thus, decreased excretion of sulphatoxymelatonin is frequently observed in cases with severe genetic disorders affecting serotonin biosynthesis. In conclusion, sulphatoxymelatonin can be a good biomarker to estimate serotonin status in the brain, especially for treatment monitoring purposes. PB Nature Publishing Group YR 2017 FD 2017-10-09 LK http://hdl.handle.net/10668/11779 UL http://hdl.handle.net/10668/11779 LA en NO Batllori M, Molero-Luis M, Arrabal L, Heras JL, Fernandez-Ramos JA, Gutiérrez-Solana LG, et al. Urinary sulphatoxymelatonin as a biomarker of serotonin status in biogenic amine-deficient patients. Sci Rep. 2017 Nov 7;7(1):14675 NO Tis work is funded by the "Plan Estatal de I+D+I and Instituto de SaludCarlos III-Subdirección General de Evaluación y Fomento de la Investigación Sanitaria", project PI15/01082, project PI14/0003 and the European Regional Development Fund (FEDER). Instituto de Salud Carlos III and the FEDER Funding Program from the European Union. CIBERER U-703. [Artuch]. Instituto de Salud Carlos III and the FEDER Funding Program from the European Union. CIBERER U-703. [Molero-Luis]. Instituto de Salud Carlos III and the FEDER Funding Program from the European Union. PI15/01082 [Ormazabal]. Tis work was supported by grants from the Instituto de Salud Carlos III. PI14/00032. [Garcia-Cazorla]. DS RISalud RD Apr 7, 2025