{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,7]],"date-time":"2026-03-07T04:27:50Z","timestamp":1772857670014,"version":"3.50.1"},"reference-count":44,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2024,2,12]],"date-time":"2024-02-12T00:00:00Z","timestamp":1707696000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Klinefelter syndrome (KS) is a male genetic disease caused by the presence of an extra X chromosome, causing endocrine disorders mainly responsible for a high rate of infertility and metabolic disorders in adulthood. Scientific research is interested in identifying new biomarkers that can be predictive or prognostic of alterations strictly connected to KS. Lipocalin-2 (LCN-2, also known as NGAL) is a small protein initially identified within neutrophils as a protein related to innate immunity. Serum LCN-2 estimation seems to be a useful tool in predicting the metabolic complications caused by several pathological conditions. However, little is known about its potential role in infertility conditions. The present pilot study aims to investigate the presence of LCN-2 in the serum of a group of pre-pubertal and post-pubertal children affected by KS, compared to healthy controls. We demonstrated for the first time the presence of elevated levels of LCN-2 in the serum of KS patients, compared to controls. This increase was accompanied, in pre-pubertal KS patients, by the loss of correlation with LH and HDL, which instead was present in the healthy individuals. Moreover, in all KS individuals, a positive correlation between LCN-2 and inhibin B serum concentration was found. Despite the limited size of the sample analyzed, our preliminary data encourage further studies to confirm the findings and to extend the study to KS adult patients, to verify the predictive\/prognostic value of LCN-2 as new biomarker for metabolic diseases and infertility associated with the pathology.<\/jats:p>","DOI":"10.3390\/ijms25042214","type":"journal-article","created":{"date-parts":[[2024,2,12]],"date-time":"2024-02-12T11:30:12Z","timestamp":1707737412000},"page":"2214","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Serum Lipocalin-2 Levels as a Biomarker in Pre- and Post-Pubertal Klinefelter Syndrome Patients: A Pilot Study"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7020-1471","authenticated-orcid":false,"given":"Roberto","family":"Paparella","sequence":"first","affiliation":[{"name":"Department of Maternal Infantile and Urological Sciences, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6129-4071","authenticated-orcid":false,"given":"Giampiero","family":"Ferraguti","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6806-9715","authenticated-orcid":false,"given":"Marco","family":"Fiore","sequence":"additional","affiliation":[{"name":"Institute of Biochemistry and Cell Biology (IBBC-CNR), Policlinico Umberto I, 00161 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michela","family":"Menghi","sequence":"additional","affiliation":[{"name":"Department of Maternal Infantile and Urological Sciences, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ginevra","family":"Micangeli","sequence":"additional","affiliation":[{"name":"Department of Maternal Infantile and Urological Sciences, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-3249-2238","authenticated-orcid":false,"given":"Francesca","family":"Tarani","sequence":"additional","affiliation":[{"name":"Department of Maternal Infantile and Urological Sciences, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aurora","family":"Ligotino","sequence":"additional","affiliation":[{"name":"Department of Maternal Infantile and Urological Sciences, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marisa Patrizia","family":"Messina","sequence":"additional","affiliation":[{"name":"Department of Maternal Infantile and Urological Sciences, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9981-8715","authenticated-orcid":false,"given":"Mauro","family":"Ceccanti","sequence":"additional","affiliation":[{"name":"SITAC, Societ\u00e0 Italiana per il Trattamento Dell\u2019alcolismo e le sue Complicanze, 00185 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonio","family":"Minni","sequence":"additional","affiliation":[{"name":"Department of Sensory Organs, Sapienza University of Rome, 00161 Roma, Italy"},{"name":"Division of Otolaryngology-Head and Neck Surgery, San Camillo de Lellis Hospital, ASL Rieti-Sapienza University, 02100 Rieti, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1737-9064","authenticated-orcid":false,"given":"Christian","family":"Barbato","sequence":"additional","affiliation":[{"name":"Institute of Biochemistry and Cell Biology (IBBC-CNR), Policlinico Umberto I, 00161 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5538-2494","authenticated-orcid":false,"given":"Marco","family":"Lucarelli","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy"},{"name":"Pasteur Institute Cenci Bolognetti Foundation, Sapienza University of Rome, 00161 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5958-9364","authenticated-orcid":false,"given":"Luigi","family":"Tarani","sequence":"additional","affiliation":[{"name":"Department of Maternal Infantile and Urological Sciences, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0651-1816","authenticated-orcid":false,"given":"Carla","family":"Petrella","sequence":"additional","affiliation":[{"name":"Institute of Biochemistry and Cell Biology (IBBC-CNR), Policlinico Umberto I, 00161 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1016\/S0140-6736(04)16678-6","article-title":"Klinefelter\u2019s Syndrome","volume":"364","author":"Lanfranco","year":"2004","journal-title":"Lancet"},{"key":"ref_2","unstructured":"Davis, S.M., and Ross, J.L. 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