Exploring the Q-marker of "sweat soaking method" processed radix Wikstroemia indica: Based on the "effect-toxicity-chemicals" study.

BACKGROUND: Radix Wikstroemia indica (RWI), named "Liao Ge Wang" in Chinese, is a kind of toxic Chinese herbal medicine (CHM) commonly used in Miao nationality of South China. "Sweat soaking method" processed RWI could effectively decrease its toxicity and preserve therapeutic effect. However, the underlying mechanism of processing is still not clear, and the Q-markers database for processed RWI has not been established. PURPOSE: Our study is to investigate and establish the quality evaluation system and potential Q-markers based on "effect-toxicity-chemicals" relationship of RWI for quality/safety assessment of "sweat soaking method" processing. METHODS: The variation of RWI in efficacy and toxicity before and after processing was investigated by pharmacological and toxicological studies. Cytotoxicity test was used to screen the cytotoxicity of components in RWI. The material basis in ethanol extract of raw and processed RWI was studied by UPLC-Q-TOF/MS. And the potential Q-markers were analyzed and predicted according to "effect-toxicity-chemical" relationship. RESULTS: RWI was processed by "sweat soaking method", which could preserve efficacy and reduce toxicity. Raw RWI and processed RWI did not show significant difference on the antinociceptive and anti-inflammatory effect, however, the injury of liver and kidney by processed RWI was much weaker than that by raw RWI. The 20 compounds were identified from the ethanol extract of raw product and processed product of RWI using UPLC-Q-TOF/MS, including daphnoretin, emodin, triumbelletin, dibutyl phthalate, Methyl Paraben, YH-10 + OH and matairesinol, arctigenin, kaempferol and physcion. Furthermore, 3 diterpenoids (YH-10, YH-12 and YH-15) were proved to possess the high toxicity and decreased by 48%, 44% and 65%, respectively, which could be regarded as the potential Q-markers for quality/safety assessment of "sweat soaking method" processed RWI. CONCLUSION: A Q-marker database of processed RWI by "sweat soaking method" was established according to the results and relationship of "effect-toxicity-chemicals", which provided a scientific evidence for processing methods, mechanism and the clinical application of RWI, also provided experimental results to explore the application of Q-marker in CHM.

Mechanism-based inhibition of CYPs and RMs-induced hepatoxicity by rutaecarpine.

1. Rutaecarpine, a quinolone alkaloid isolated from the unripe fruit of Evodia rutaecarpa, is one of the main active components used in a variety of clinical applications, including the treatment of hypertension and arrhythmia. However, its hepatotoxicity has also been reported in recent years. 2. Reactive metabolites (RMs) play a vital role in drug-induced liver injury. Rutaecarpine has a secondary amine structure that may be activated to RMs. The aim of the study was to investigate the inhibition of rutaecarpine on CYPs and explore the possible relationship between RMs and potential hepatotoxicity. 3. A cell counting kit-8 cytotoxicity assay indicated that rutaecarpine can decrease the primary rat hepatocyte viability, increase lactate dehydrogenase and reactive oxygen species, reduce JC-1, and cause cell stress and membrane damage. The indexes were significantly restored by adding ABT, an inhibitor of CYPs. A cocktail assay showed that CYP1A2, CYP2C9, CYP2C19, CYP2E1 and CYP3A4 can be inhibited by rutaecarpine in human liver microsomes. The IC50 values of CYP1A2 with and without NADPH were 2.2 and 7.4 µM, respectively, which presented a 3.3 shift. The results from a metabolic assay indicated that three mono-hydroxylated metabolites and two di-hydroxylated metabolites were identified and two GSH conjugates were also trapped. 4. Rutaecarpine can inhibit the activities of CYPs and exhibit a potential mechanism-based inhibition on CYP1A2. RMs may cause herb-drug interactions, providing important information for predicting drug-induced hepatotoxicity.