{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,3]],"date-time":"2026-10-03T18:14:43Z","timestamp":1791051283790,"version":"4.1.0"},"reference-count":45,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,1,22]],"date-time":"2021-01-22T00:00:00Z","timestamp":1611273600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Federal Ministry of Education and Research (BMBF) to the German Center for Diabetes Research (DZD e.V)","award":["01GI0925"],"award-info":[{"award-number":["01GI0925"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>The hepatokine fetuin A (Fet A) has been associated with diverse pathological states such as insulin resistance, type 2 diabetes, macrovascular disease, and systemic ectopic and vascular calcification. Fet A may also play a role in tumor growth and metastasis. The biological activity of Fet A may be affected by various modifications, including phosphorylation, O- and N-glycosylation and fatty acid binding. We developed an antibody-based assay for the detection of Fet A phosphorylated at serine 312. Fatty acid pattern was determined by gas chromatography. Using the antibody, we found that the phosphorylation was stable in human plasma or serum at room temperature for 8 h. We observed that Fet A is present in several glycosylation forms in human plasma, but the extent of Ser312 phosphorylation was not associated with glycosylation. The phosphorylation pattern did not change during an oral glucose tolerance test (0\u2013120 min). We further found that human Fet A binds preferentially saturated fatty acids (&gt;90%) at the expense of mono- and poly-unsaturated fatty acids. Our results indicate that different molecular species of Fet A are present in human plasma and that these different modifications may determine the different biological effects of Fet A.<\/jats:p>","DOI":"10.3390\/jcm10030411","type":"journal-article","created":{"date-parts":[[2021,1,22]],"date-time":"2021-01-22T11:13:53Z","timestamp":1611314033000},"page":"411","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Detection and Characterization of Phosphorylation, Glycosylation, and Fatty Acid Bound to Fetuin A in Human Blood"],"prefix":"10.3390","volume":"10","author":[{"given":"Mark\u00e9ta","family":"Kov\u00e1\u0159ov\u00e1","sequence":"first","affiliation":[{"name":"Department for Diagnostic Laboratory Medicine, Institute for Clinical Chemistry and Pathobiochemistry, 72076 T\u00fcbingen, Germany"},{"name":"Institute for Diabetes Research, and Metabolic Diseases of the Helmholtz Center Munich, at the Eberhard-Karls-University of T\u00fcbingen, 72076 T\u00fcbingen, Germany"},{"name":"German Center for Diabetes Research (DZD), 72076 T\u00fcbingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hubert","family":"Kalbacher","sequence":"additional","affiliation":[{"name":"Interfaculty Institute of Biochemistry, at the Eberhard-Karls-University T\u00fcbingen, 72076 T\u00fcbingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Peter","sequence":"additional","affiliation":[{"name":"Department for Diagnostic Laboratory Medicine, Institute for Clinical Chemistry and Pathobiochemistry, 72076 T\u00fcbingen, Germany"},{"name":"Institute for Diabetes Research, and Metabolic Diseases of the Helmholtz Center Munich, at the Eberhard-Karls-University of T\u00fcbingen, 72076 T\u00fcbingen, Germany"},{"name":"German Center for Diabetes Research (DZD), 72076 T\u00fcbingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hans-Ulrich","family":"H\u00e4ring","sequence":"additional","affiliation":[{"name":"Institute for Diabetes Research, and Metabolic Diseases of the Helmholtz Center Munich, at the Eberhard-Karls-University of T\u00fcbingen, 72076 T\u00fcbingen, Germany"},{"name":"Department of Internal Medicine IV, Division of Endocrinology, Diabetology and Nephrology, University of T\u00fcbingen, 72076 T\u00fcbingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0236-8760","authenticated-orcid":false,"given":"Triantafyllos","family":"Didangelos","sequence":"additional","affiliation":[{"name":"Diabetes Center, 1st Propaedeutic Department of Internal Medicine, Medical School, \u201cAHEPA\u201d Hospital, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Norbert","family":"Stefan","sequence":"additional","affiliation":[{"name":"Institute for Diabetes Research, and Metabolic Diseases of the Helmholtz Center Munich, at the Eberhard-Karls-University of T\u00fcbingen, 72076 T\u00fcbingen, Germany"},{"name":"German Center for Diabetes Research (DZD), 72076 T\u00fcbingen, Germany"},{"name":"Department of Internal Medicine IV, Division of Endocrinology, Diabetology and Nephrology, University of T\u00fcbingen, 72076 T\u00fcbingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Birkenfeld","sequence":"additional","affiliation":[{"name":"Institute for Diabetes Research, and Metabolic Diseases of the Helmholtz Center Munich, at the Eberhard-Karls-University of T\u00fcbingen, 72076 T\u00fcbingen, Germany"},{"name":"German Center for Diabetes Research (DZD), 72076 T\u00fcbingen, Germany"},{"name":"Department of Internal Medicine IV, Division of Endocrinology, Diabetology and Nephrology, University of T\u00fcbingen, 72076 T\u00fcbingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erwin","family":"Schleicher","sequence":"additional","affiliation":[{"name":"Department for Diagnostic Laboratory Medicine, Institute for Clinical Chemistry and Pathobiochemistry, 72076 T\u00fcbingen, Germany"},{"name":"Institute for Diabetes Research, and Metabolic Diseases of the Helmholtz Center Munich, at the Eberhard-Karls-University of T\u00fcbingen, 72076 T\u00fcbingen, Germany"},{"name":"German Center for Diabetes Research (DZD), 72076 T\u00fcbingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0584-1138","authenticated-orcid":false,"given":"Konstantinos","family":"Kantartzis","sequence":"additional","affiliation":[{"name":"Institute for Diabetes Research, and Metabolic Diseases of the Helmholtz Center Munich, at the Eberhard-Karls-University of T\u00fcbingen, 72076 T\u00fcbingen, Germany"},{"name":"German Center for Diabetes Research (DZD), 72076 T\u00fcbingen, Germany"},{"name":"Department of Internal Medicine IV, Division of Endocrinology, Diabetology and Nephrology, University of T\u00fcbingen, 72076 T\u00fcbingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1016\/bs.acc.2018.12.003","article-title":"Clinical implications of fetuin-A","volume":"89","author":"Jirak","year":"2019","journal-title":"Adv. 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