Pharmacological effects of Huangqin Decoction prepared from roots of multi-originated peony on ulcerative colitis in mice:a comparative study

Abstract

Huangqin Decoction(HQD) is a classic prescription for treating dysentery in the Treatise on Cold Damage and now is mainly used for the treatment of ulcerative colitis(UC). Since there are no requirements on specific Paeonia species, both Paeoniae Radix Alba(white peony root, WPR) and Paeoniae Radix Rubra(red peony root, RPR) are clinically used in HQD now. Although the two types of peony roots are close in origin and similar in primary components, the medicinal properties and efficacies are different. Furthermore, the systematic comparative analysis on the efficacy differences in treating UC of HQD with the roots of multi-originated peony has been seldom reported. This study compared and evaluated the pharmacological effects of HQD prepared from the roots of multi-originated peony, including WPR, RPR-l(derived from P. lactiflora), and RPR-v(derived from P. veitchii) based on the mouse model of UC induced by dextran sodium sulfate(DSS) by animal behaviors, pathological section(colon), and cytokine expression(IL-1β and IL-6), aiming to provide evidence for the identification of the original resource of peony root in HQD. The results indicated that all HQD samples prepared from WPR, RPR-l, and RPR-v could improve the symptoms of UC. Compared with the HQD-WPR, HQD-RPR-l and HQD-RPR-v were significantly different in weight loss, colon length, and disease activity index(DAI) score, but there was no significant difference between HQD-RPR-l and HQD-RPR-v. Moreover, HQD-RPR-v exhibited the most significant improvement in the pathological morphology of colonic tissue and mucosal defects. According to the previous comparative analysis of chemical profiling and content distribution of HQD prepared from the roots of multi-originated peony, RPR-v in HQD was potent in protecting against UC, which was presumedly attributed to a large number of monoterpene glycosides and galloyl glucoses. This study provided a scientific basis for the determination of peony root in HQD and its clinical medication.