[Equivalence of combined decoction and mixed single decoctions of Gegen Qinlian Decoction in alleviating chemotherapy-associated diarrhea].

ABSTRACT

This study compared the chemical profiles, component content, dry paste yield, and pharmacological effects of samples obtained from the mixed single decoctions and the combined decoction of Gegen Qinlian Decoction(GQD), aiming to provide an experimental foundation for evaluating the equivalence of the two decocting methods and the suitability of TCM formula granules in clinical application. The same decoction process was used to prepare the combined decoction and mixed single decoctions of GQD. Ultra-performance liquid chromatography coupled with Q-Exactive Orbitrap mass spectrometry(UPLC-Q-Exactive Orbitrap MS) was employed to compare the chemical profiles between the two groups. High-performance liquid chromatography(HPLC) was used to compare the content of nine characteristic components between the two groups. Then, a delayed diarrhea mouse model induced by irinotecan was established to compare the pharmacological effects of the two groups on chemotherapy-induced diarrhea. The UPLC-Q-Exactive Orbitrap MS in ESI~+ and ESI~- modes identified 59 chemical components in the compound decoction and mixed single decoctions, which showed no obvious differences in component species. The content of baicalin and wogonoside was higher in the compound decoction, while that of puerarin, daidzein-8-C-apiosylglucoside, berberine, epiberberine, wogonin, glycyrrhizic acid, and daidzein was higher in the mixed single decoctions. Further statistical analysis revealed no significant difference in the content of the nine characteristic components between the compound decoction and the mixed single decoctions. The dry paste yield had no significant difference between the two groups. Compared with the model group, both compound decoction and mixed single decoctions alleviated the weight loss and reduced diarrhea index in mice. Both of them lowered the levels of tumor necrosis factor-α(TNF-α), interleukin-1ß(IL-1ß), cyclooxygenase-2(COX-2), intercellular adhesion molecule-1(ICAM-1), interleukin-10(IL-10), malondialdehyde(MDA), and nitric oxide(NO) in the colon tissue. Furthermore, they significantly increased the levels of glutathione peroxidase(GSH-Px) and superoxide dismutase(SOD). Hematoxylin-eosin(HE) staining showed that colon tissue cells were tightly arranged with clear nuclei in both groups without obvious difference. The compound decoction and mixed single decoctions showed no significant differences in chemical component species, content of nine characteristic components, dry paste yield, or the pharmacological effects on alleviating chemotherapy-induced diarrhea. The findings provide a reference for evaluating the flexibility and superiority of combined or single decocting method in the preparation of TCM decoctions or formula granules.