Metabolic profile of Rhizoma coptidis in human plasma determined using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry.

RATIONALE: Rhizoma coptidis extract and its alkaloids show various pharmacological activities, but its metabolic profile in human plasma has not been thoroughly investigated. In the present research, the metabolism of Rhizoma coptidis at a clinical dose (5 g/60 kg/day) was systematically analyzed to determine its biotransformation processes in human plasma. METHODS: In this research, the metabolites of Rhizoma coptidis in human plasma after oral administration of Rhizoma coptidis extract at a clinical dose were investigated using ultra-high-performance liquid chromatography (UHPLC) coupled with high-resolution LTQ-Orbitrap mass spectrometry. The structural elucidation of the constituents was confirmed by comparing their retention times (tR ) and MSn fragments with those of standards and literature reports. RESULTS: In total, two prototypes and twelve metabolites were detected in human plasma. The two prototypes were confidently identified using reference standards. Of the compounds detected, M7 (berberrubinen-9-O-glucuronide) was the most abundant based on its peak area, which indicates that this compound might be a pharmacokinetic marker for Rhizoma coptidis alkaloids in humans. Based on the metabolites detected in human plasma, a possible metabolic pathway for Rhizoma coptidis in vivo was proposed. CONCLUSIONS: The results indicated that the alkaloids in Rhizoma coptidis were extensively biotransformed in vivo mainly via conjugation with glucuronic acid (GluA) or sulfuric acid (SulA) to form phase II metabolites, and the GluA metabolites are likely the dominant form in human plasma. To the best of our knowledge, this is the first in vivo evaluation of the metabolic profile of the whole Rhizoma coptidis extract in human plasma, which is essential for determining the chemicals responsible for the pharmacological activities of Rhizoma coptidis in vivo. Moreover, it would be beneficial for us to further systematically study the pharmacokinetic behavior of Rhizoma coptidis in humans.

Metabolic profile of Fructus Gardeniae in human plasma and urine using ultra high-performance liquid chromatography coupled with high-resolution LTQ-orbitrap mass spectrometry.

1. In China, Fructus Gardeniae was used as a traditional Chinese medicine (TCM) with a wide array of biological activities. The bioactive components identified in Fructus Gardeniae mainly included iridoids, flavonids, pigments, and so on. Among them, iridoids were regarded as important compounds in Fructus Gardeniae. Though analyses of the constituents in biological samples after oral administration of Fructus Gardeniae effective fraction or its active compounds have been reported, few efforts have been made to investigate the metabolic profile of Fructus Gardeniae in humans. In this study, the constituents and metabolites of Fructus Gardeniae in human blood and urine after oral administration of Fructus Gardeniae were investigated using ultra high-performance liquid chromatography (UHPLC) coupled with high-resolution LTQ-Orbitrap mass spectrometery. 2. Totally, 14 constituents (two parent compounds and 12 metabolites) of Fructus Gardeniae were identified in human plasma and urine either by comparing the retention time and mass spectrometry data with that of reference compounds or by the accurate high-resolution MS/MS data of the chemicals. The compounds identified were mainly iridoid glycosides such as geniposide and the derivatives of genipin-O-glucuronide. Among them, 11 metabolites were detected in human plasma and urine while the other three metabolites including geniposidic acid (M1), demethylation derivative of genipin-O-glucuronide (M2), and dehydration product of mono-hydroxylated genipin-O-glucuronide (M9) were only discovered in human urine. Further, the possible metabolic pathways of Fructus Gardeniae in vivo were proposed and the peak area-time curve of the most abundant metabolite genipin-O-glucuronide (M13) in human plasma after oral administration of Fructus Gardeniae was depicted. The results suggested that a metabolic difference existed between rats and humans. 3. The results obtained in the present research would provide basic information to understand the metabolic profile of Fructus Gardeniae in humans and explore the chemicals responsible for the hepatotoxicity of Fructus Gardeniae in vivo. Moreover, it would be beneficial for us to further study the pharmacokinetic behavior of Fructus Gardeniae in humans systematically.