{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T09:58:20Z","timestamp":1771840700850,"version":"3.50.1"},"reference-count":23,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,2,22]],"date-time":"2026-02-22T00:00:00Z","timestamp":1771718400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT, Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia, I.P., RISE","award":["LA\/P\/0053\/2020"],"award-info":[{"award-number":["LA\/P\/0053\/2020"]}]},{"name":"Institute of Biomedicine","award":["UIDB\/04501\/2020"],"award-info":[{"award-number":["UIDB\/04501\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Type 2 diabetes (T2D) causes systemic metabolic and inflammatory changes that affect the oral cavity, but salivary molecular markers remain poorly characterized. A peptide-centric reanalysis of salivary proteomics data was performed using DIA-NN for peptide-level quantification, without collapsing peptide signals into protein-level summaries. Although the qualitative peptide repertoire was largely conserved between T2D and control samples (&gt;96% overlap), T2D showed coordinated quantitative changes in specific peptide subsets. Differentially abundant peptides primarily originated from complement C3, alpha-2-macroglobulin, serotransferrin, mucins, apolipoproteins, and hemoglobin, with a significant enrichment of oxidized cysteine-containing peptides, indicating redox imbalance and low-grade inflammation. Structural analysis with AlphaFold showed that T2D-associated peptides are located in solvent-exposed and conformationally dynamic regions of proteins. These findings suggest that disease specificity in diabetic saliva occurs mainly at the peptide level, offering mechanistic insight into non-invasive biomarker identification and longitudinal disease monitoring.<\/jats:p>","DOI":"10.3390\/ijms27042040","type":"journal-article","created":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T08:58:21Z","timestamp":1771837101000},"page":"2040","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Peptide-Centric DIA-NN Reanalysis Uncovers Structurally Coherent Salivary Signatures of Type 2 Diabetes"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3636-5805","authenticated-orcid":false,"given":"Rui","family":"Vitorino","sequence":"first","affiliation":[{"name":"iBiMED, Department of Medical Sciences, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"RISE, Department of Surgery and Physiology, Faculty of Medicine, University of Porto, 4099-002 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1038\/s41368-023-00231-6","article-title":"Salivary biomarkers: Novel noninvasive tools to diagnose chronic inflammation","volume":"15","author":"Dongiovanni","year":"2023","journal-title":"Int. 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