Analysis of Biomarkers in Diabetic Foot Ulcer Patients With Dampness-Heat Syndrome Based on 4D-DIA Proteomics...

Diabetic foot ulcer (DFU), a severe complication of diabetes, impose substantial global health burdens. Dampness-heat syndrome (DHS), a common syndrome in traditional Chinese medicine (TCM), is highly prevalent among DFU patients and closely correlated with treatment response and prognosis. However, the molecular biomarkers associated with DFU in patients with DHS remain poorly understood.

Serum 4D-data-independent acquisition (DIA) proteomics was performed on 16 DFU-DHS patients and six healthy controls (HCs). Differentially expressed proteins (DEPs) were screened by |fold change (FC)| > 1.2 and p < 0.05. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and protein-protein interaction (PPI) analyses were conducted. Key biomarkers were validated via enzyme-linked immunosorbent assay (ELISA) in 28 independent DFU-DHS cases.

A total of 201 DEPs were identified between DFU-DHS patients and HCs. Bioinformatics revealed DEPs enriched in lipid metabolism (high-density lipoprotein [HDL] remodeling and cholesterol metabolism) and complement-coagulation cascades. PPI network analysis revealed a core functional module centered on four proteins, APOA1, LCAT, PLTP, and CETP. ELISA validation confirmed the significant dysregulation of these four apolipoproteins in the independent DFU-DHS cohort (all p < 0.05 vs. HCs). The combination of the biomarkers APOA1, LCAT, PLTP, and CETP exhibited a high diagnostic efficacy for DFU-DHS, with an area under the curve (AUC) of 0.9672 based on receiver operating characteristic (ROC) analysis.

To our knowledge, this is the first study to employ 4D-DIA proteomics on DFU-DHS. We identified four serum biomarkers (APOA1, LCAT, PLTP, and CETP) linked to dysregulated cholesterol metabolism in DFU-DHS patients, which show diagnostic potential and provide insights for integrating TCM syndrome differentiation with precision medicine.