Serum-derived exosome proteomics unveils the distinct and adjustable nature of the dampness constitution in traditional Chinese medicine

In Traditional Chinese Medicine (TCM), dampness is a pathogenic factor arising from impaired production and transportation of bodily fluids. While Fuling Zexie decoction (FLZXD) has demonstrated therapeutic efficacy in dampness constitution (DC) treatment, the material basis underlying its constitutional modulatory effects remains unclear. This study proposes objective indicators for the differentiation and therapeutic evaluation of DC and elucidates the material basis of FLZXD in DC treatment. Serum exosome proteomic profiling was conducted across two independent cohorts to identify DC-related indicators and assess the therapeutic efficacy of FLZXD in DC-associated hyperlipidemia (DC-hyperlipidemia). The bioactive compounds of FLZXD were prioritized through a comprehensive analysis of patent documentation and network pharmacology, with subsequent validation of DC-related targets using enzyme-linked immunosorbent assay (ELISA). Proteomic analysis of serum exosomes revealed signatures that differentiate individuals with a balanced constitution (BC) from those with DC. The differentially expressed proteins (DEPs) were enriched predominantly in pathways related to the complement cascade and cardiovascular diseases. FLZXD demonstrated therapeutic efficacy against DC-hyperlipidemia, as evidenced by the reversal of DEPs expression following treatment, which was supported by the patentable findings and network pharmacology analysis. Through experimental validation and pharmacological evidence, the active herbs of FLZXD (Fuling, Zexie and Baizhu, collectively referred to as FZB) were identified, and a total of 73 putative therapeutic targets involved in the dampness-resolving effects of FZB were revealed. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment further confirmed that FLZXD exerts its anti-dampness effects primarily through regulation of the complement and coagulation cascades. Among eight candidate indicators specifically associated with DC, four proteins were validated via ELISA, indicating potential utility for the differentiation of DC. The specificity (%), specificity (%), fold change (FC), p-value, and area under the curve (AUC) for each indicator were as follows: apolipoprotein B-100 (APOB) (100.00, 80.00, 0.63, 0.0008, 0.94), complement factor H-related protein 1 (CFHR1) (90.00, 100.00, 0.55, 0.0002, 0.98), alpha-1-acid glycoprotein 1 (ORM1) (100.00, 80.00, 0.71, 0.0015, 0.92), and pigment epithelium-derived factor (SERPINF1) (90.00, 70.00, 0.66, 0.0052, 0.87). The integrative approach, combining proteomic profiling, network pharmacology analysis, and clinical validation, establishes an integrative approach for research on TCM constitutions. This approach provides (1) molecular insights into the differentiation of DC, (2) a foundation for mechanism-based, targeted therapeutic strategies, and (3) enhanced patient stratification to support personalized treatment approaches.