Identification of In Vivo Components in Shiduqing Capsule Using High‐Resolution Mass Spectrometry and Network Pharmacology‐Based Analysis of Its Therapeutic Mechanisms Against Eczema

Shiduqing Capsule, a clinically widely used Chinese patent medicine, is indicated for skin itching, dryness, and desquamation caused by blood deficiency with wind-dryness syndrome. However, the tissue distribution characteristics of its active components in vivo and its pharmacological mechanisms in treating eczema remain unclear. This study aims to identify the bioactive components of Shiduqing Capsule, characterize their in vivo tissue distribution patterns, and subsequently elucidate the underlying therapeutic mechanisms against eczema based on these findings. This study employed high-resolution mass spectrometry (HRMS) coupled with the Global Natural Products Social Molecular Networking (GNPS) platform to comprehensively identify the chemical constituents of Shiduqing Capsule in vivo, while simultaneously characterizing their tissue-specific distribution profiles. Furthermore, network pharmacology approaches were utilized to systematically investigate the therapeutic mechanisms underlying Shiduqing Capsule's efficacy against eczema. Through systematic chemical composition analysis, 51 blood-absorbed components were identified in Shiduqing Capsule using advanced analytical techniques. Further GNPS-assisted mass spectrometry analysis revealed its predominant composition of flavonoids, lipids, terpenoids, and phenylpropanoids. Network pharmacology investigation demonstrated that the capsule's anti-eczema effects are mediated through critical pathways including TNF signaling and Th17 cell differentiation. This study systematically analyzed the in vivo components of Shiduqing Capsule and their tissue distribution characteristics, while elucidating the underlying mechanisms of its therapeutic effects against eczema.