Metabolomics technology combined with O2PLS analysis reveals the active components of Paeoniae Radix Alba in preventing renal damage in rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by symmetrical, erosive polyarthritis and multi-organ involvement, with renal complications posing a life-threatening risk. Paeoniae Radix Alba, known as BaiShao (BS) in Chinese, is a widely used herbal medicine for clinical RA treatment, yet its potential in preventing RA-associated renal damage and its underlying active ingredients remain elusive. To address this knowledge gap, we employed a type II collagen-induced arthritis (CIA) rat model. Biochemical assays and histopathological analyses confirmed that BS exerted robust renoprotective effects in CIA rats. Serum and urine metabolomics identified 48 renal damage-related biomarkers, 18 of which showed distinct regulatory trends following BS intervention. Meanwhile, ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF/MS) was used to characterize 34 chemical components in BS. Through an integrative approach that combines two-way orthogonal partial least squares (O2PLS) and Pearson correlation analysis, 18 active ingredients were identified as key mediators of BS-mediated renoprotection. Collectively, this study establishes a novel metabolomics-O2PLS strategy for discovering active ingredients in BS, laying a foundation for understanding the mechanism underlying the prevention of RA-associated renal damage mediated by BS and providing insights for the development of novel preventive therapeutics.