Compatibility effects of herb pair Phellodendri chinensis cortex and Anemarrhenae rhizoma on benign prostatic hyperplasia using targeted metabolomics

Phellodendri chinensis cortex (P. C. cortex) and Anemarrhenae rhizoma (A. rhizoma) herb pair is a core component of traditional Chinese medicines used to treat inflammation and benign prostatic hyperplasia (BPH). The present study was designed to profile the arachidonic acid (AA) metabolomic characteristics in rat plasma and prostate after being treated with P. C. cortex and A. rhizoma as well as their combination. Plasma and prostate samples from sham group, BPH model group, herb pair group and two single herb groups were collected on days 7, 14, 21 and 28. Then, a systemic metabolomic analysis based on UFLC‐MS/MS was employed to quantify AA and its cyclooxygenase and lipoxygenase pathway metabolites (15‐HETE, 12‐HETE, 5‐HETE, AA, PGI₂, PGF_2α, 8‐HETE, PGD₂, PGE₂ and LTB₄). The results demonstrated that BPH led a significant increase of 10 biomarkers in plasma and tissue (p < 0.05). The clusters of herb pair group and single herb groups showed a tendency to return to the initial space, and the AA and its metabolites from those groups were differently downregulated to a healthier level, with the combination of single herbs most obvious. The present study demonstrated that P. C. cortex–A. rhizoma herb pair might produce synergistic or complementary compatibility effects on suppressing inflammatory processes occurring in BPH.