Elucidation of the potential mechanism of Euphorbiae Pekinensis Radix and Glycyrrhizae Radix for the remission of ascites in hepatocellular carcinoma using a comprehensive strategy based on chinmedomics, pharmacology, and biopharmaceutics.

As recorded in Traditional Chinese medicine (TCM) theory, Euphorbiae Pekinensis Radix (EPR) and Glycyrrhizae Radix (GR) compose one herbal pair of the so-called "Eighteen Incompatible Medicaments". The EPR-GR combination has displayed potential in the treatment of malignant ascites. However, the validity of this theory has been challenged due to insufficient evidence. In this study, the chemical substance responsible for the compatibility between GR and EPR was systematically analyzed by UPLC-Q-TOF-MS and chemical methods. SD rats were used to evaluate the toxicity of EPR and EPR-GR. Serum and several tissues were collected for biochemical analysis, histopathological examination, and chinmedomics. A mouse model of H22 HCC ascites was established to observe the therapeutic effects. The relationship between the expression of renal aquaporins (AQPs) and the therapeutic effect of EPR-GR on liver cancer ascites was investigated. Finally, the in vitro biopharmaceutical properties were investigated. The result showed that the contents of most of the chemical components in EPR tended to increase after pairing with GR, and the contents of the pairing markers increased significantly. Elevated blood levels of ellagic acid (EA) and decreased levels of 3,3'-di-O-methyl ellagic acid-4'-O-β-D-xylopyranoside (DEAX), and 3,3'-di-O-methyl ellagic acid (DEA), were observed after compounding GR with EPR. EPR can cause damage to intestinal tissues, and when combined with GR, it can cause slight damage to the liver and spleen. EPR can reduce body weight, waist circumference, and ascites volume in mice with liver cancer ascites and alleviate the symptoms of ascites in liver cancer. The therapeutic effect of the EPR-GR combination was better than EPR. The combined GR enhanced the down-regulation of AQP2 and AQP3. Molecular docking results confirmed that the blood components of EPR, EA, DEAX and DEA, could be stably bound to AQP2/AQP3 proteins. After compounding with GR and its components, the BCS classification of EPR was unchanged but shifted toward high solubility and low permeability. The findings indicate that GR-EPR could exhibit significant potential in mitigating ascites associated with hepatocellular carcinoma.