{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,20]],"date-time":"2026-05-20T03:29:22Z","timestamp":1779247762523,"version":"3.51.4"},"reference-count":69,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2023,8,5]],"date-time":"2023-08-05T00:00:00Z","timestamp":1691193600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Sj\u00f6gren\u2019s Foundation","award":["UL1TR002544"],"award-info":[{"award-number":["UL1TR002544"]}]},{"DOI":"10.13039\/100006108","name":"National Center for Advancing Translational Sciences","doi-asserted-by":"publisher","award":["UL1TR002544"],"award-info":[{"award-number":["UL1TR002544"]}],"id":[{"id":"10.13039\/100006108","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Sj\u00f6gren\u2019s disease (SjD) is the second most prevalent autoimmune disorder that involves chronic inflammation of exocrine glands. Correct diagnosis of primary SjD (pSjD) can span over many years since disease symptoms manifest only in advanced stages of salivary and lachrymal glandular destruction, and consensus diagnostic methods have critical sensitivity and selectivity limitations. Using nuclear magnetic resonance (NMR) spectroscopy, we determined the composition of metabolites in unstimulated saliva samples from 30 pSjD subjects and 30 participants who do not have Sj\u00f6gren\u2019s disease (non-Sj\u00f6gren\u2019s control group, NS-C). Thirty-four metabolites were quantified in each sample, and analysis was conducted on both non-normalized (concentration) and normalized metabolomics data from all study participants (ages 23\u201378) and on an age-restricted subset of the data (ages 30\u201370) while applying false discovery rate correction in determining data significance. The normalized data of saliva samples from all study participants, and of the age-restricted subset, indicated significant increases in the levels of glucose, glycerol, taurine, and lactate, as well as significant decreases in the levels of 5-aminopentanoate, acetate, butyrate and propionate, in subjects with pSjD compared to subjects in the NS-C group. Additionally, a significant increase in choline was found only in the age-restricted subset, and a significant decrease in fucose was found only in the whole study population in normalized data of saliva samples from the pSjD group compared to the NS-C group. Metabolite concentration data of saliva samples from all study participants, but not from the age-restricted subset, indicated significant increases in the levels of glucose, glycerol, taurine, and lactate in subjects with pSjD compared to controls. The study showed that NMR metabolomics can be implemented in defining salivary metabolic signatures that are associated with disease status, and can contribute to differential analysis between subjects with pSjD and those who are not affected with this disease, in the clinic.<\/jats:p>","DOI":"10.3390\/molecules28155891","type":"journal-article","created":{"date-parts":[[2023,8,5]],"date-time":"2023-08-05T10:25:36Z","timestamp":1691231136000},"page":"5891","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Identification of Salivary Metabolic Signatures Associated with Primary Sj\u00f6gren\u2019s Disease"],"prefix":"10.3390","volume":"28","author":[{"given":"Addy","family":"Alt-Holland","sequence":"first","affiliation":[{"name":"Department of Endodontics, Tufts University School of Dental Medicine, One Kneeland Street, Boston, MA 02111, USA"},{"name":"Tufts University School of Dental Medicine, One Kneeland Street, Boston, MA 02111, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xuejian","family":"Huang","sequence":"additional","affiliation":[{"name":"Program in Pharmacology and Drug Development, Tufts University Graduate School of Biomedical Sciences, 136 Harrison Avenue, Boston, MA 02111, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tatiana","family":"Mendez","sequence":"additional","affiliation":[{"name":"Tufts University School of Dental Medicine, One Kneeland Street, Boston, MA 02111, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mabi L.","family":"Singh","sequence":"additional","affiliation":[{"name":"Department of Diagnostics Sciences, Division of Oral Medicine, Tufts University School of Dental Medicine, One Kneeland Street, Boston, MA 02111, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Athena S.","family":"Papas","sequence":"additional","affiliation":[{"name":"Department of Diagnostics Sciences, Division of Oral Medicine, Tufts University School of Dental Medicine, One Kneeland Street, Boston, MA 02111, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joseph","family":"Cimmino","sequence":"additional","affiliation":[{"name":"Department of Diagnostics Sciences, Division of Oral Medicine, Tufts University School of Dental Medicine, One Kneeland Street, Boston, MA 02111, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tiffany","family":"Bairos","sequence":"additional","affiliation":[{"name":"Department of Diagnostics Sciences, Division of Oral Medicine, Tufts University School of Dental Medicine, One Kneeland Street, Boston, MA 02111, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elizabeth","family":"Tzavaras","sequence":"additional","affiliation":[{"name":"Department of Diagnostics Sciences, Division of Oral Medicine, Tufts University School of Dental Medicine, One Kneeland Street, Boston, MA 02111, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elizabeth","family":"Foley","sequence":"additional","affiliation":[{"name":"Department of Diagnostics Sciences, Division of Oral Medicine, Tufts University School of Dental Medicine, One Kneeland Street, Boston, MA 02111, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sarah E.","family":"Pagni","sequence":"additional","affiliation":[{"name":"Department of Public Health and Community Service, Division of Biostatistics and Experimental Design, Tufts University School of Dental Medicine, One Kneeland Street, Boston, MA 02111, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4841-0247","authenticated-orcid":false,"given":"James D.","family":"Baleja","sequence":"additional","affiliation":[{"name":"Program in Pharmacology and Drug Development, Tufts University Graduate School of Biomedical Sciences, 136 Harrison Avenue, Boston, MA 02111, USA"},{"name":"Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA"},{"name":"Department of Medical Education, Tufts University Graduate School of Biomedical Sciences, 136 Harrison Avenue, Boston, MA 02111, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,5]]},"reference":[{"key":"ref_1","first-page":"247","article-title":"The epidemiology of Sj\u00f6gren\u2019s syndrome","volume":"6","author":"Patel","year":"2014","journal-title":"Clin. 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