Integrated multi-omics approaches and network pharmacology analysis to explore the diagnosis and regulatory role of active metabolites in allergy.

Allergy is a common immune response often triggered by foods, medicine, and pollution, significantly affecting human health. Small-molecule metabolites, as the most direct phenotypic manifestations of biological systems, can directly elucidate gene functions and molecular mechanisms. However, the roles and mechanisms of small-molecule metabolites in allergies remain incompletely understood. In this study, we established an integrated strategy combining metabolomics, network pharmacology, and proteomics to identify active metabolites and clarify their regulatory roles in bovine serum albumin (BSA)-induced allergy. 61 differential metabolites associated with allergy were identified and validated through untargeted and targeted metabolomic analyses of plasma. Combining network pharmacology and proteomics, eight activated differential metabolites affect the complement and coagulation cascades pathway through the proteins F10, F2, and PLG in BSA-induced allergy. This mechanism was further corroborated by proteomic validation of 12 related proteins altered in the complement and coagulation cascades pathway. Through correlation and receiver operating characteristic (ROC) analyses, six diagnostic biomarkers for diagnosing BSA allergy were screened, with area under the ROC curve values exceeding 0.94. Metabolites No. 39 (Glutamylphenylalanine) and 43 (hippuraldehyde sulphate) show excellent sensitivity and accuracy for diagnosing BSA-induced allergy and play a key role in modulating the complement and coagulation cascade. This study found that active metabolites could serve as critical factors and diagnostic biomarkers in allergic responses, offering novel insights into the underlying mechanisms of allergy.