Identification of chemical constituents and pharmacokinetic characteristics of Xiaoyan Tuire Granule in rats

Xiaoyan Tuire Granule is a type of Chinese patent medicine that has been proven effective in treating respiratory tract infections. However, while it has been successfully introduced into clinical use, more knowledge is still needed regarding its chemical components and pharmacokinetics. This study investigated the chemical profile in the medicine and rat plasma by ultra high-performance liquid chromatography coupled with Q Exactive hybrid quadrupole-orbitrap high-resolution accurate mass spectrometry (UHPLC-Orbitrap-MS/MS). Subsequently, it developed a validated ultra high-performance liquid chromatography coupled with quadrupole mass spectrometry (UHPLC-MS/MS) method for determining five components in rat plasma after oral administration of Xiaoyan Tuire Granule. As a result, a total of 106 constituents were inferred, including 9 terpenoids, 29 flavonoids, 33 organic acids, 12 phenylpropanoids and 23 other compounds. After administration, 86 compounds were inferred in rat plasma, including 73 prototypes and 13 metabolites. The metabolic pathways were primarily hydrogenation, glucuronic acid conjugation, sulfate conjugation, hydrolysis and methylation. The established method determined the contents of esculetin, esculin, isovitexin, caffeic acid and p-coumaric acid had a good separation, and all the legal verification met the requirements. The pharmacokinetic results indicate that the absorption rate of the five compounds in vivo was rapid, with a Tmax of less than 0.25 h, and the elimination rate was also fast, with a half-time (T1/2) ranging from 1.22 h to 2.19 h. It is worth noting that esculin and esculetin have similar half-time in vivo due to their structural similarities. Among these five compounds, the AUC0-∞ and MRT0-∞ of p-coumaric acid and esculetin were relatively higher, indicating higher exposure and longer residence time of both compounds in vivo. In conclusion, this paper researched the chemical constituents and pharmacokinetics of Xiaoyan Tuire Granule, which provided the reference for further study.

Metabolic profiles of Fufang Xiling Jiedu capsule in rats by ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry

Fufang Xiling Jiedu capsule (FXJC), a traditional Chinese medicine that evolved from "Yinqiao Powder", is widely used for the treatment of cold and influenza. However, due to a lack of in vivo metabolism research, the chemical components responsible for the therapeutic effects still remain unclear. Hence, this study aimed to describe the metabolic profiles of the FXJC in rat plasma, urine, and feces. A combined data mining strategy based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry was employed and 201 xenobiotics, including 117 prototype components and 84 metabolites were detected. Phenolic acids, flavonoids, triterpenes, and lignans were prominent ingredients absorbed in vivo, and the major metabolic pathways of the detected metabolites were glucuronidation, sulfation, methylation, and oxidation. This is the first systematic study on the metabolism of the FXJC in vivo, providing valuable information for future studies on the efficacy, toxicity, and mechanism of the FXJC.

Glycyrrhizae Radix et Rhizoma: The popular occurrence of herbal medicine applied in classical prescriptions

Glycyrrhizae Radix et Rhizoma is a well-known herbal medicine with a wide range of pharmacological functions that has been used throughout Chinese history. This review presents a comprehensive introduction to this herb and its classical prescriptions. The article discusses the resources and distribution of species, methods of authentication and determination chemical composition, quality control of the original plants and herbal medicines, dosages use, common classical prescriptions, indications, and relevant mechanisms of the active content. Pharmacokinetic parameters, toxicity tests, clinical trials, and patent applications are discussed. The review will provide a good starting point for the research and development of classical prescriptions to develop herbal medicines for clinical use.

Metabolic profile and potential mechanisms of Wendan decoction on coronary heart disease by ultra-high-performance quadrupole time of flight-mass spectrometry combined with network pharmacology analysis

Wendan decoction, a well-known classical traditional Chinese medicine prescription, has been widely used in the clinical application of coronary heart disease for thousands of years. However, due to a lack of research on the overall metabolism of Wendan decoction, the bioavailable components responsible for the therapeutic effects remain unclear, hindering the revelation of its mechanisms against coronary heart disease. Consequently, an efficient joint research pattern combined with characterization of the metabolic profile and network pharmacology analysis was proposed. As a result, a total of 172 Wendan decoction-related xenobiotics (57 prototypes and 115 metabolites) were detected based on the exploration of the typical metabolic pathways of representative pure compounds in vivo, describing their multi-component metabolic characteristics comprehensively. Subsequently, an integrated network of "herbs-bioavailable compounds-coronary heart disease targets-pathways-therapeutic effects" was constructed, and its seven compounds were finally screened out as the key components acting on five main targets of coronary heart disease. Overall, this work not only provided a crucial biological foundation for interpreting the effective components and action mechanisms of Wendan decoction on coronary heart disease but also showed a reference value for revealing the bioactive components of traditional Chinese medicine prescriptions.

Chemical analysis of the Chinese herbal medicine licorice (Gan-Cao): An update review

ETHNOPHARMACOLOGICAL RELEVANCE

Licorice, called Gan-Cao in China, is one of the most popular traditional herbal medicines. It is derived from the dried roots and rhizomes of Glycyrrhiza uralensis, G. glabra, and G. inflata. Licorice is recorded in the pharmacopoeias of China, Japan, US, and Europe.

AIM

This review updates research progress of licorice from the perspectives of chemical analysis, quality evaluation, drug metabolism, and pharmacokinetic studies from 2009 to April 2022.

MATERIALS AND METHODS

Both English and Chinese literatures were collected from databases including PubMed, Elsevier, Web of Science, and CNKI (Chinese). Licorice, extraction, structural characterization/identification, quality control, metabolism, and pharmacokinetics were used as keywords.

RESULTS

Newly developed analytical methods, including LC/UV, 2DLC, LC/MS, GC/MS, and mass spectrometry imaging (MSI) for chemical analysis of licorice were summarized.

CONCLUSION

This review provides a comprehensive summary on chemical analysis of licorice.

Study on the metabolism profile of flavanomarein in Coreopsis tinctoria Nutt

Coreopsis tinctoria Nutt. (family Asteraceae) is a popular medicine-food plant, which improves chronic diseases such as hyperlipemia, hypertension, and diabetes. Flavanomarein is the main active component of Coreopsis tinctoria Nutt, in which the blood concentration of volunteers is low and bioavailability is poor. Thus, the understanding of flavanomarein metabolites and metabolic pathways is significant to clarify its effectiveness. This study systematically studied the metabolites of flavanomarein by oral and injection. The biological samples (feces, urine, and plasma) were analyzed by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry in negative ion mode. The metabolic law of flavanomarein in the liver was further verified by a liver microsomal incubation experiment in vitro. A total of 12 metabolites were identified by oral administration while 15 metabolites were detected by injection. It was shown that metabolic pathways include acetylation, hydroxylation, glucuronidation, methylation, dehydrogenation, etc. The liver extraction rate of flavanomarein was 0.08, which means the metabolic stability of flavanomarein is well in rats' liver microsomes. It is a systematic study on the metabolism of flavanomarein and provides a metabolic rationale for further in-depth in vivo biotransformation. This article is protected by copyright. All rights reserved.

Rapid analysis of components in Qizhiweitong tablets and plasma after oral administration in rats by UPLC-Q-TOF-MS/MS based on self-developed database

Qizhiweitong is a famous traditional Chinese prescription medicine. It has been used to treat various stomach disorders, such as functional dyspepsia, chronic gastritis, and intestinal stress syndrome for a long time and gives favorable therapeutic effects in clinical settings. However, its chemical composition and possible bioactive components are not completely known. In the present study, we used ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS) and qualitatively analyzed the chemical composition of Qizhiweitong tablet extract and the absorbed prototype constituents along with corresponding metabolites in rat plasma following oral administration of Qizhiweitong tablet on the basis of our self-developed component database that was established accurately and rapidly. We detected a total of 119 compounds and 61 xenobiotics in the Qizhiweitong tablet, which included 32 prototypes and 28 metabolites. The results of the present study laid a solid foundation for quality marker screening and integrative pharmacology-based study on the Qizhiweitong tablet.

Explore the Potential Ingredients for Detoxification of Honey-Fired Licorice (ZGC) Based on the Metabolic Profile by UPLC-Q-TOF-MS

Licorice is well known for its ability to reduce the toxicity of the whole prescription in traditional Chinese medicine theory. However, honey-fired licorice (ZGC for short), which is made of licorice after being stir-fried with honey water, is more commonly used for clinical practice. The metabolism in vivo and detoxification-related compounds of ZGC have not been fully elucidated. In this work, the chemical constituents in ZGC and its metabolic profile in rats were both identified by high ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). The network pharmacology was applied to predict the potential detoxifying ingredients of ZGC. As a result, a total of 115 chemical compounds were identified or tentatively characterized in ZGC aqueous extract, and 232 xenobiotics (70 prototypes and 162 metabolites) were identified in serum, heart, liver, kidneys, feces, and urine. Furthermore, 41 compounds absorbed in serum, heart, liver, and kidneys were employed for exploring the detoxification of ZGC by network pharmacology. Ultimately, 13 compounds (five prototypes including P5, P24, P30, P41 and P44, and 8 phase Ⅰ metabolites including M23, M47, M53, M93, M100, M106, M118, and M134) and nine targets were anticipated to be potential mediums regulating detoxification actions. The network pharmacology analysis had shown that the ZGC could detoxify mainly through regulating the related targets of cytochrome P450 and glutathione. In summary, this study would help reveal potential active ingredients in vivo for detoxification of ZGC and provided practical evidence for explaining the theory of traditional Chinese medicine with modern technology.

Integrated UPLC-Q-TOF-MS/MS and Network Pharmacology Approach to Investigating the Metabolic Profile of Marein of Coreopsis tinctoria Nutt

Marein is the main active compound of Coreopsis tinctoria Nutt., and its main activities include antioxidant, hypoglycemic, and hypotensive. After oral administration of marein, the blood concentration of marein is low. The metabolites of marein have not been reported systematically. In this study, a rapid and systematic method based on ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) was established to detect metabolites of marein in vivo (plasma and urine) after oral administration and injection. Sixty-one metabolites were identified. The metabolites are formed through a wide range of metabolic reactions, including hydroxylation, glucuronidation, methylation, hydrolysis, and desorption of hydrogen. The liver microsome incubation was further used to investigate the metabolic rate of marein. Network pharmacology was applied to study the targets and pathways of marein and its metabolites. Marein and its metabolites act on the same targets to enhance the therapeutic effect. This research illuminates the metabolites and metabolic reaction of marein and establishes a basis for the development and rational utilization of C. tinctoria. Meanwhile, the analysis of prototype and metabolites together by network pharmacology techniques could provide a methodology for the study of component activity.

Metabolomic Profiling and Antioxidant Activities of Breonadia salicina Using 1H-NMR and UPLC-QTOF-MS Analysis

Breonadia salicina (Vahl) Hepper and J.R.I. Wood is widely used in South Africa and some other African countries for treatment of various infectious diseases such as diarrhea, fevers, cancer, diabetes and malaria. However, little is known about the active constituents associated with the biological activities. This study is aimed at exploring the metabolomics profile and antioxidant constituents of B. salicina. The chemical profiles of the leaf, stem bark and root of B. salicina were comprehensively characterized using proton nuclear magnetic resonance (¹H-NMR) spectroscopy and ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS). The antioxidant activities of the crude extracts, fractions and pure compounds were determined using the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging and reducing power assays. A total of 25 compounds were tentatively identified using the UPLC-QTOF-MS. Furthermore, the ¹H-NMR fingerprint revealed that the different parts of plant had differences and similarities among the different crude extracts and fractions. The crude extracts and fractions of the root, stem bark and leaf showed the presence of α-glucose, β-glucose, glucose and fructose. However, catechin was not found in the stem bark crude extracts but was found in the fractions of the stem bark. Lupeol was present only in the root crude extract and fractions of the stem bark. Furthermore, 5-O-caffeoylquinic acid was identified in the methanol leaf extract and its respective fractions, while the crude extracts and fractions from the root and dichloromethane leaf revealed the presence of hexadecane. Column chromatography and preparative thin-layer chromatography were used to isolate kaempferol 3-O-(2″-O-galloyl)-glucuronide, lupeol, d-galactopyranose, bodinioside Q, 5-O-caffeoylquinic acid, sucrose, hexadecane and palmitic acid. The crude methanol stem bark showed the highest antioxidant activity in the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging activity with an IC₅₀ value of 41.7263 ± 7.6401 μg/mL, whereas the root crude extract had the highest reducing power activity with an IC_0.5 value of 0.1481 ± 0.1441 μg/mL. Furthermore, the ¹H-NMR and UPLC-QTOF-MS profiles showed the presence of hydroxycinnamic acids, polyphenols and flavonoids. According to a literature survey, these phytochemicals have been reported to display antioxidant activities. Therefore, the identified hydroxycinnamic acid (caffeic acid), polyphenol (ellagic acid) and flavonoids (catechin and (epi) gallocatechin) significantly contribute to the antioxidant activity of the different parts of plant of B. salicina. The results obtained in this study provides information about the phytochemistry and phytochemical compositions of Breonadia salicina, confirming that the species is promising in obtaining constituents with medicinal potential primarily antioxidant potential.

Simultaneous LC-MS/MS bioanalysis of alkaloids, terpenoids, and flavonoids in rat plasma through salting-out-assisted liquid-liquid extraction after oral administration of extract from Tetradium ruticarpum and Glycyrrhiza uralensis: a sample preparation strategy to broaden analyte coverage of herbal medicines

Herbal medicines have historically been practiced in combinatorial way, which achieves therapeutic efficacy by integrative effects of multi-components. Thus, the accurate and precise measurement of multi bioactive components in matrices is inalienable to understanding the metabolism and disposition of herbal medicines. In this study, aiming to provide a strategy that improves analyte coverage, evaluation of six protocols employing sample pretreatment methods- protein precipitation (PPT), liquid-liquid extraction (LLE), sugaring-out-assisted liquid-liquid extraction (SULLE), and salting-out-assisted liquid-liquid extraction (SALLE)- was performed by LC-MS/MS using rat plasma and a mixture of alkaloid (evodiamine, rutaecarpine, dehydroevodiamine), terpenoid (limonin, rutaevin, obacunone), and flavonoid (liquiritin, isoliquiritin, liquiritigenin) standards isolated from Tetradium ruticarpum and Glycyrrhiza uralensis. These protocols were as follows: (1) PPT with methanol, (2) PPT with acetonitrile, (3) LLE with methyl tertiary-butyl ether-dichloromethane, (4) LLE with ethyl acetate-n-butanol, (5) SALLE with ammonium acetate, (6) SULLE with glucose. The results suggested that SALLE produced broader analyte coverage with satisfactory reproducibility, acceptable recovery, and low matrix interference. Then, sample preparation procedure of SALLE, chromatographic conditions, and mass spectrometric parameters were optimized, followed by method validation, showing that good sensitivity (LLOQ ≤ 1 ng mL^-1), linearity (r ≥ 0.9933), precision (RSD ≤ 14.45%), accuracy (89.54~110.87%), and stability could be achieved. Next, the developed method was applied successfully to determine the pharmacokinetic behavior of the nine compounds in rat plasma after intragastric administration with an extract from Tetradium ruticarpum and Glycyrrhiza uralensis (Wuzhuyu-Gancao pair). Based on an extensive review and experiments, a sample preparation procedure that matches with LC-MS/MS technique and can get wider analyte coverage was outlined. The developed SALLE method is rapid, reliable, and suitable for bioanalysis of analytes with diverse polarity, which was expected to be a promising strategy for the pharmacokinetic studies of herbal medicines. Graphical abstract.

Classification-based strategies to simplify complex traditional Chinese medicine (TCM) researches through liquid chromatography-mass spectrometry in the last decade (2011-2020): Theory, technical route and difficulty

The difficulty of traditional Chinese medicine (TCM) researches lies in the complexity of components, metabolites, and bioactivities. For a long time, there has been a lack of connections among the three parts, which is not conducive to the systematic elucidation of TCM effectiveness. To overcome this problem, a classification-based methodology for simplifying TCM researches was refined from literature in the past 10 years (2011-2020). The theoretical basis of this methodology is set theory, and its core concept is classification. Its starting point is that "although TCM may contain hundreds of compounds, the vast majority of these compounds are structurally similar". The methodology is composed by research strategies for components, metabolites and bioactivities of TCM, which are the three main parts of the review. Technical route, key steps and difficulty are introduced in each part. Two perspectives are highlighted in this review: set theory is a theoretical basis for all strategies from a conceptual perspective, and liquid chromatography-mass spectrometry (LC-MS) is a common tool for all strategies from a technical perspective. The significance of these strategies is to simplify complex TCM researches, integrate isolated TCM researches, and build a bridge between traditional medicines and modern medicines. Potential research hotspots in the future, such as discovery of bioactive ingredients from TCM metabolites, are also discussed. The classification-based methodology is a summary of research experience in the past 10 years. We believe it will definitely provide support and reference for the following TCM researches.

The integrated study on the chemical profiling and in vivo course to explore the bioactive constituents and potential targets of Chinese classical formula Qingxin Lianzi Yin Decoction by UHPLC-MS and network pharmacology approaches

ETHNOPHARMACOLOGICAL RELEVANCE

Qingxin Lianzi Yin Decoction (QXLZY), a Chinese classical formula, has been widely used in the treatment of various chronic kidney diseases over 1,000 years. However, the current studies on QXLZY were mostly focused on its clinical efficacy, lacking systematic material basis research on constituents.

AIM OF THE STUDY

This work aims to elucidate and quantify the chemical constituents, clarify the blood-absorbed components and excretion pathways, predict major bioactive constituents and discover potential therapeutic targets.

MATERIALS AND METHODS

UHPLC-LTQ-Orbitrap HRMS was employed to clarify the chemical constituents and metabolites of QXLZY. The extraction of diagnostic ion and neutral loss fragment was aimed for searching specific type of constituents. The plasma, urine, bile and feces samples of rats after oral administration of QXLZY were systematically studied. UHPLC-QQQ-MS/MS was employed to simultaneously detect different types of constitutes. Based on the analysis of ingredients in vivo, the bioactive constituents and potential therapeutic targets in the treatment of diabetic nephropathy (DN) was investigated by using network pharmacological analysis.

RESULTS

Totally, 220 compounds were identified or tentatively characterized by UHPLC-LTQ-Orbitrap HRMS. Among them, 59 compounds were confirmed by reference standards. Meanwhile, 21 representative components were simultaneously determined within 15 min by UHPLC-QQQ-MS/MS. 123 components (74 prototypes as well as 49 metabolites) were identified or tentatively characterized. By using network pharmacological analysis, baicalein, liquiritigenin, succinic acid, formononetin, wogonin might be the major effective constituents in QXLZY during the treatment of DN.

CONCLUSIONS

Flavonoids, saponins and organic acids were the major chemical ingredients of QXLZY. Flavonoids were the main components absorbed into blood, followed by organic acids. Phase II conjugation reaction was the major metabolic type. The pathways that QXLZY in the treatment of DN were probably related to glucose and lipid metabolism, oxidative stress and inflammation.

Rapid Profiling and Identification of Vitexin Metabolites in Rat Urine, Plasma and Faeces after Oral Administration Using a UHPLC-Q-Exactive Orbitrap Mass Spectrometer Coupled with Multiple Data-mining Methods

BACKGROUND

Vitexin is a natural flavonoid compound with multiple pharmacological activities and is extracted from the leaves and seeds of Vitex negundo L. var. cannabifolia (Sieb. et Zucc.) Hand.-Mazz. However, the metabolite characterization of this component remains insufficient.

OBJECTIVE

To establish a rapid profiling and identification method for vitexin metabolites in rat urine, plasma and faeces after oral administration using a UHPLC-Q-Exactive orbitrap mass spectrometer were coupled with multiple data-mining methods.

METHODS

In this study a simple and rapid systematic strategy for the detection and identification of constituents was proposed based on UHPLC-Q-Exactive Orbitrap mass spectrometry in parallel reaction monitoring mode combining diagnostic fragment ion filtering techniques.

RESULTS

A total of 49 metabolites were fully or partially characterized based on their accurate mass, characteristic fragment ions, retention times, corresponding ClogP values, and so on. It is obvious that C-glycosyl flavonoids often display an [M+H-120]⁺ ion that represents the loss of C₄H₈O₄. As a result, these metabolites were presumed to be generated through glucuronidation, sulfation, deglucosylation, dehydrogenation, methylation, hydrogenation, hydroxylation, ring cleavage and their composite reactions. Moreover, the characteristic fragmentation pathways of flavonoids, chalcones and dihydrochalcones were summarized for the subsequent metabolite identification.

CONCLUSION

The current study provided an overall metabolic profile of vitexin which will be of great help in predicting the in vivo pharmacokinetic profiles and understanding the action mechanism of this active ingredient.

A comprehensive profiling and identification of liquiritin metabolites in rats using ultra-high-performance liquid chromatography coupled with linear ion trap-orbitrap mass spectrometer

Liquiritin (LQ), a main component of liquorice, exerts various biological activities. However, insufficient attentions have been paid to the metabolism study on this natural compound until now. Our present study was conducted to investigate the LQ metabolites in rats urine, faeces and plasma using UHPLC-LTQ-Orbitrap mass spectrometer in both positive and negative ion modes. Meanwhile, post-acquisition data-mining methods including high-resolution extracted ion chromatogram (HREIC), multiple mass defect filters (MMDFs), neutral loss fragments (NLFs) and diagnostic product ions (DPIs) were utilised to screen and identify LQ metabolites from HR-ESI-MS to ESI-MSⁿ stage. As a result, a total of 49 metabolites were detected and characterised unambiguously or tentatively. These metabolites were presumed to generate through glucuronidation, sulfation, deglucosylation, dehydrogenation, methylation, hydrogenation, hydroxylation, ring cleavage and their composite reactions. Our results not only provided novel and useful data to better understand the biological activities of LQ, but also indicated that the proposed strategy was reliable for a rapid discovery and identification drug-related constituents in vivo.

Global Profiling and Structural Characterization of Metabolites of Ononin Using HPLC-ESI-IT-TOF-MSn After Oral Administration to Rats

Ononin is a bioactive isoflavone of legumes. To explore the "effective forms" of ononin, its metabolites were characterized using HPLC-ESI-IT-TOF-MSⁿ after oral administration to rats. Metabolites (106), including 94 new metabolites, were characterized, which contained 17 phase I, 23 hydroxylated and methylated, 54 sulfated, 10 glucuronidated, and 2 sulfated and glucuronidated metabolites. Six hydroxylated metabolites of formononetin (aglycone of ononin) were simultaneously detected for the first time. Twenty-three hydroxylated and methylated metabolites were the new metabolites of ononin, and the number of hydroxylation and methylation was 1-3 and 1-2. Twenty metabolites have ononin-related bioactivities, and many metabolites have the same bioactivities. Their probable mechanisms of action may be additive and/or synergistic effects, especially because of the addition of the blood concentrations of these compounds. The results provide a foundation for a better understanding of the "effective forms" of ononin.

Comprehensive investigation of mechanism and effective ingredients of Fangji Huangqi Tang by serum pharmacochemistry and network pharmacology

Fangji Huangqi Tang (FHT), has been reported to show effects on nephrotic syndrome, but its mechanism of action and bioactive components have not yet been determined. In this study, a method using UPLC-HRMS/MS was established for the detection and identification of the chemical constituents and metabolites absorbed into the blood. Absorbed components in serum were then used for the network pharmacology analysis to deduce the mechanism and effective components. A total of 86 compounds were identified or tentatively characterized. Based on the same instrumental conditions, 85 compounds were found in rat serum after oral administration of FHT, including 22 prototypes and 63 metabolites. Network pharmacology analysis showed that absorbed components, such as (3R)-2',3',4',7-tetrahydroxyisoflavan, astrapterocarpan, cycloastragenol, 7,2'-dihydroxy-3',4'-dimethoxyisoflavan, astragaloside IV, astrapterocarpan glucoside and glycyrrhetinic acid, could be responsible for the pharmacological activity of nephrotic syndrome by regulating the VEGF signaling pathway, focal adhesion and MAPK signaling pathway. Furthermore, the pathway-target network showed that the MAPK1, AKT2 and CDC42 were involved in the signal pathways above. This study provides a scientific basis for the mechanism and effective ingredients of FHT.

A simple method for evaluation pharmacokinetics of glycyrrhetinic acid and potential drug-drug interaction between herbal ingredients

A simple validated high performance liquid chromatography method was developed for the evaluation of the effect of three kinds of active ingredients in traditional Chinese medicine (TCM) on the pharmacokinetics of glycyrrhetinic acid (GA),a kind of active component from the most commonly used TCM licorice. Our results revealed that all of the calibration curves displayed good linearity. Intra- and inter-day precision for GA ranged from 2.54 to 3.98% and from 4.95 to 7.08%, respectively. The recovery rates for GA were determined to be 96.3–106.4%. All the samples showed satisfactory precision and accuracy in various stability tests. Plasma pharmacokinetic parameters including area under the concentration-time curve (AUC), elimination half-life (t_1/2), time to peak concentration(T_max) and peak concentration C_max were calculated. No significant difference was found as compared the groups administrating GA with and without other ingredients from TCM.

Memory Enhancement by Oral Administration of Extract of Eleutherococcus senticosus Leaves and Active Compounds Transferred in the Brain

The pharmacological properties of Eleutherococcus senticosus leaf have not been clarified although it is taken as a food item. In this study, the effects of water extract of Eleutherococcus senticosus leaves on memory function were investigated in normal mice. Oral administration of the extract for 17 days significantly enhanced object recognition memory. Compounds absorbed in blood and the brain after oral administration of the leaf extract were detected by LC-MS/MS analyses. Primarily detected compounds in plasma and the cerebral cortex were ciwujianoside C3, eleutheroside M, ciwujianoside B, and ciwujianoside A1. Pure compounds except for ciwujianoside A1 were administered orally for 17 days to normal mice. Ciwujianoside C3, eleutheroside M, and ciwujianoside B significantly enhanced object recognition memory. These results demonstrated that oral administration of the leaf extract of E. senticosus enhances memory function, and that active ingredients in the extract, such as ciwujianoside C3, eleutheroside M, and ciwujianoside B, were able to penetrate and work in the brain. Those three compounds as well as the leaf extract had dendrite extension activity against primary cultured cortical neurons. The effect might relate to memory enhancement.

The influence of compatibility of Si-Ni decoction with metabolism in intestinal bacteria on transports of toxic diterpenoid alkaloids from processed aconite root across Caco-2 monolayers

ETHNOPHARMACOLOGICAL RELEVANCE

In traditional Chinese medicine, processed aconite root (lateral root of Aconitum carmichaelii Debx.) is used as the principle herb of the Si-Ni decoction (SND) formula due to its cardiotonic effect, while its cardiotoxicity and neurotoxicity caused by diester and monoester diterpenoid alkaloids are reduced by compatibility of dried ginger and honey-processed liquorice in SND.

AIM OF THE STUDY

To investigate the detoxification of processed aconite root by compatibility of SND from the perspective of intestinal absorption with metabolism in intestinal bacteria.

MATERIALS AND METHODS

Decoctions of processed aconite root (AD), processed aconite root and honey-processed liquorice (ALD), and SND with the same amount of each herb were prepared, then were incubated in human intestinal bacteria juice (IBJ) in vitro for different durations. Bidirectional transmembrane transports of these decoctions and their IBJ-incubated decoctions were conducted on Caco-2 monolayers. Correlation between efflux ratios changes of benzoylmesaconine, benzoylaconine, benzoylhypaconine (monoester-diterpenoid alkaloids, MDAs) and hypaconitine (diester-diterpenoid alkaloids) from processed aconite root, and metabolic trends of compounds from honey-processed liquorice and dried ginger were also performed.

RESULTS

The absorption of MDAs from processed aconite root was increased by combination with honey-processed liquorice in ALD, but they were decreased significantly by the addition of dried ginger in SND. Take benzoylhypaconine for example, the P_{app, AP to BL} soared from (3.13 ± 0.18) × 10^-7 cm/s in AD to (23.32 ± 3.51) × 10^-7 cm/s in ALD, while it dropped to (1.12 ± 0.17) × 10^-7 cm/s in SND. When herb combined decoctions metabolised by intestinal bacteria for 12 h, the efflux ratio of benzoylhypaconine were both increased from 0.56 to 1.21 in ALD and from 1.10 to 2.61 in SND, which was correlative with the generation of davidigenin and glycyrrhetic acid (the metabolites of chalcones and pentacyclic triterpenoids from liquorice) in ALD and with the metabolism of [6]-gingerol (the major compound from dried ginger) in SND, respectively.

CONCLUSIONS

Compatibility of SND altered the intestinal absorption of toxic MDAs and hypaconitine from processed aconite root. In SND, dried ginger rather than honey-processed liquorice played the role of detoxification of these toxic compounds in the intestinal absorption. The intestinal detoxification of SND was significantly and strongly correlative with metabolism of dried ginger and honey-processed liquorice by intestinal bacteria, simultaneously.

UPLC-Q-TOF-MS and UPLC-MS/MS methods for metabolism profiles and pharmacokinetics of major compounds in Xuanmai Ganjie Granules

Xuanmai Ganjie Granules (XMGJ), a widely used Chinese herbal formula in the clinic, is used for treatment of sore throats and coughs. Despite the chemical constituents having been clarifying by our previous studies, both of the metabolism and pharmacokinetic studies of XMGJ are unclear. This study aimed to explore the disposition process of XMGJ in vivo. A sensitive and selective ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) method was developed to analyze the absorbed components and metabolites in rat plasma and urine after oral administration of XMGJ. A total of 42 absorbed components, including 16 prototype compounds and 26 metabolites, were identified or tentatively characterized in rat plasma and urine after oral administration of XMGJ. Moreover, the pharmacokinetic studies of five compounds of XMGJ were investigated using ultra-high liquid chromatography with tandem mass spectrometry method. The results indicated that liquiritin, harpagoside, glycyrrhetic acid, liquiritigenin, formononetin and their metabolites might be the major components involved in the pharmacokinetic and metabolism process of XMGJ. This research showed a comprehensive investigation of XMGJ in vivo, which could provide a meaningful basis for further material basis and pharmacological as well as toxicological research.

Ultrahigh-performance liquid chromatography coupled with triple quadrupole and time-of-flight mass spectrometry for the screening and identification of the main flavonoids and their metabolites in rats after oral administration of Cirsium japonicum DC. extract

RATIONALE

Cirsium japonicum DC., a traditional Chinese medicine, has been shown to have anti-haemorrhagic and anti-tumour effects. Pharmacological studies have demonstrated that this curative effect may be related to flavonoids. The present work aimed to screen and identify the main flavonoids and their corresponding metabolites in rats after oral administration of Cirsium japonicum DC. extract.

METHODS

A rapid and simple method based on ultrahigh-performance liquid chromatography coupled with triple quadrupole and time-of-flight mass spectrometry (UHPLC/QTOF-MS) was developed for the identification of the primary absorbing components and metabolites of the principal flavonoids. The absorbing components were first characterized, followed by the selection of representative constituents. In this study, the main flavonoids, pectolinarin, linarin and pectolinarigenin, were selected as templates to identify possible metabolites.

RESULTS

A total of 27 metabolites were detected in rat blood, urine and bile samples. A hydrolysis reaction was the first step for pectolinarin and linarin, followed by oxidation and reduction reactions. However, phase II metabolites for pectolinarin and linarin were not detected. The primary biotransformation routes of pectolinarigenin were identified as oxidation, reduction, hydrolysis, and glucuronide and glucose conjugation.

CONCLUSIONS

The metabolic pathways of pectolinarin, linarin and pectolinarigenin were summarized. This study not only proposed a practical strategy for rapidly screening and identifying metabolites but also provided useful information for further pharmacological studies and the design of new drugs based on Cirsium japonicum DC.

A targeted strategy to identify untargeted metabolites from in vitro to in vivo: Rapid and sensitive metabolites profiling of licorice in rats using ultra-high performance liquid chromatography coupled with triple quadrupole-linear ion trap mass spectrometry

It is challenging to conduct in vivo metabolic study for traditional Chinese medicines (TCMs) because of complex components, unpredictable metabolic pathways and low metabolite concentrations. Herein, we proposed a sensitive strategy to characterize TCM metabolites in vivo at an orally clinical dose using ultra-high performance liquid chromatography-triple quadrupole-linear ion trap mass spectrometry (UHPLC-QTRAP-MS). Firstly, the metabolism of individual compounds in rat liver microsomes was studied to obtain the metabolic pathways and fragmentation patterns. The untargeted metabolites in vitro were detected by multiple ion monitoring-enhanced product ion (EPI) and neutral loss-EPI scans. Subsequently, a sensitive multiple reaction monitoring-EPI method was developed according to the in vitro results and predicted metabolites to profile the in vivo metabolites. Licorice as a model herb was used to evaluate and validate our strategy. A clinical dose of licorice water extract was orally administered to rats, then a total of 45 metabolites in urine, 21 metabolites in feces and 35 metabolites in plasma were detected. Among them, 18 minor metabolites have not been reported previously and 6 minor metabolites were first detected in vivo. Several isomeric metabolites were well separated and differentiated in our strategy. These results suggested that this new strategy could be widely used for the detection and characterization of in vivo metabolites of TCMs.

Plasma Pharmacokinetic Determination of Canagliflozin and Its Metabolites in a Type 2 Diabetic Rat Model by UPLC-MS/MS

Canagliflozin is a novel, orally selective inhibitor of sodium-dependent glucose co-transporter-2 (SGLT2) for the treatment of patients with type 2 diabetes mellitus. In this study, a sensitive and efficient UPLC-MS/MS method for the quantification of canagliflozin and its metabolites in rat plasma was established and applied to pharmacokinetics in a type 2 diabetic rat model. We firstly investigated the pharmacokinetic changes of canagliflozin and its metabolites in type 2 diabetic rats in order to use canagliflozin more safely, reasonably and effectively. We identified three types of O-glucuronide metabolites (M5, M7 and M17), two kinds of oxidation metabolites (M8 and M9) and one oxidation and glucuronide metabolite (M16) using API 5600 triple-TOF-MS/MS. Following liquid–liquid extraction by tert-butyl methyl ether, chromatographic separation of canagliflozin and its metabolites were performed on a Waters XBridge BEH C18 column (100 × 2.1 mm, 2.5 μm) using 0.1% acetonitrile–formic acid (75:15, v/v) as the mobile phase at a flow rate of 0.7 mL/min. Selected ion monitoring transitions of m/z 462.00→191.10, 451.20→153.10, 638.10→191.10 and 478.00→267.00 were chosen to quantify canagliflozin, empagliflozin (IS), O-glucuronide metabolites (M5, M7 and M17), and oxidation metabolites (M9) using an API 5500-triple-MS/MS in the positive electrospray ionization mode. The validation of the method was found to be of sufficient specificity, accuracy and precision. The pathological condition of diabetes could result in altered pharmacokinetic behaviors of canagliflozin and its metabolites. The pharmacokinetic parameters (AUC_0–t, AUC_0–∞, CL_z/F, and V_z/F) of canagliflozin were significantly different between the CTRL and DM group rats (p < 0.05 or p < 0.01), which may subsequently cause different therapeutic effects.

Pharmacokinetics of Chinese medicines: strategies and perspectives

The modernization and internationalization of Chinese medicines (CMs) are hampered by increasing concerns on the safety and the efficacy. Pharmacokinetic (PK) study is indispensable to establish concentration-activity/toxicity relationship and facilitate target identification and new drug discovery from CMs. To cope with tremendous challenges rooted from chemical complexity of CMs, the classic PK strategies have evolved rapidly from PK study focusing on marker/main drug components to PK-PD correlation study adopting metabolomics approaches to characterize associations between disposition of global drug-related components and host metabolic network shifts. However, the majority of PK studies of CMs have adopted the approaches tailored for western medicines and focused on the systemic exposures of drug-related components, most of which were found to be too low to account for the holistic benefits of CMs. With an area under concentration-time curve- or activity-weighted approach, integral PK attempts to understand the PK-PD relevance with the integrated PK profile of multiple co-existing structural analogs (prototyes/metabolites). Cellular PK-PD complements traditional PK-PD when drug targets localize inside the cells, instead of at the surface of cell membrane or extracellular space. Considering the validated clinical benefits of CMs, reverse pharmacology-based reverse PK strategy was proposed to facilitate target identification and new drug discovery. Recently, gut microbiota have demonstrated multifaceted roles in drug efficacy/toxicity. In traditional oral intake, the presystemic interactions of CMs with gut microbiota seem inevitable, which can contribute to the holistic benefits of CMs through biotransforming CMs components, acting as the peripheral target, and regulating host drug disposition. Hence, we propose a global PK-PD approach which includes the presystemic interaction of CMs with gut microbiota and combines omics with physiologically based pharmacokinetic modeling to offer a comprehensive understanding of the PK-PD relationship of CMs. Moreover, validated clinical benefits of CMs and poor translational potential of animal PK data urge more research efforts in human PK study.

UPLC/ESI-QTOF-MS-based metabolomics survey on the toxicity of triptolide and detoxication of licorice

Triptolide (TP) from Tripterygium wilfordii has been demonstrated to possess anti-inflammatory, immunosuppressive, and anticancer activities. TP is specially used for the treatment of awkward rheumatoid arthritis, but its clinical application is confined by intense side effects. It is reported that licorice can obviously reduce the toxicity of TP, but the detailed mechanisms involved have not been comprehensively investigated. The current study aimed to explore metabolomics characteristics of the toxic reaction induced by TP and the intervention effect of licorice water extraction (LWE) against such toxicity. Obtained urine samples from control, TP and TP + LWE treated rats were analyzed by UPLC/ESI-QTOF-MS. The metabolic profiles of the control and the TP group were well differentiated by the principal component analysis and orthogonal partial least squares-discriminant analysis. The toxicity of TP was demonstrated to be evolving along with the exposure time of TP. Eight potential biomarkers related to TP toxicity were successfully identified in urine samples. Furthermore, LWE treatment could attenuate the change in six of the eight identified biomarkers. Functional pathway analysis revealed that the alterations in these metabolites were associated with tryptophan, pantothenic acid, and porphyrin metabolism. Therefore, it was concluded that LWE demonstrated interventional effects on TP toxicity through regulation of tryptophan, pantothenic acid, and porphyrin metabolism pathways, which provided novel insights into the possible mechanisms of TP toxicity as well as the potential therapeutic effects of LWE against such toxicity.

Prenylation enhances the biological activity of dietary flavonoids by altering their bioavailability

Flavonoids are distributed across the plant kingdom and have attracted substantial attention owing to their potential benefits for human health. Several studies have demonstrated that flavonoids prenylation enhances various biological activities, suggesting an attractive tool for developing functional foods. This review provides an overview of the current knowledge on how prenylation influences the biological activity and bioavailability of flavonoids. The enhancement effect of prenylation on the biological activities of dietary flavonoids in mammals was demonstrated by comparing the effect of 8-prenyl naringenin (8PN) with that of parent naringenin in the prevention of disuse muscle atrophy in mice. This enhancement results from higher muscular accumulation of 8PN than naringenin. As to bioavailability, despite the lower absorption of 8-prenyl quercetin (8PQ) compared with quercetin, higher 8PQ accumulation was found in the liver and kidney. These data imply that prenylation interferes with the elimination of flavonoids from tissues.

Characterization of the global metabolic profile of liquiritin in rat plasma, urine, bile and feces based on UHPLC-FT-ICR MS

Liquiritin is a major flavonoid in Radix Glycyrrhizae and it has been reported to possess various pharmacological activities. In the present work, a strategy based on an ultra high performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry (UHPLC-FT-ICR MS) method was proposed to systematically characterize the in vivo metabolites of liquiritin for the first time. After oral administration of liquiritin to rats in a single dose of 120 mg kg⁻¹, the rat plasma, urine, feces and bile samples were collected and used to discover metabolites. As a result, besides the parent drug, a total of 76 metabolites (6 phase I and 70 phase II metabolites) of liquiritin were detected and tentatively identified. It was indicated that the metabolic pathways of liquiritin in rats included oxidation, reduction, deglycosylation, isomerization, methylation, glucuronidation and sulfation. In summary, the results could provide valuable information regarding the metabolism of liquiritin in rats, which could contribute to a better understanding of its action mechanism.

Liquiritin is a major flavonoid in Radix Glycyrrhizae and it has been reported to possess various pharmacological activities.

Antitussive and expectorant activities of licorice and its major compounds

Licorice has been used as an antitussive and expectorant herbal medicine for a long history. This work evaluated the activities of 14 major compounds and crude extracts of licorice, using the classical ammonia-induced cough model and phenol red secretion model in mice. Liquiritin apioside (1), liquiritin (2), and liquiritigenin (3) at 50 mg/kg (i.g.) could significantly decrease cough frequency by 30-78% (p < .01). The antitussive effects could be partially antagonized by the pretreatment of methysergide or glibenclamide, but not naloxone. Moreover, compounds 1-3 showed potent expectorant activities after 3 days treatment (p < .05). The water and ethanol extracts of licorice, which contain abundant 1 and 2, could decrease cough frequency at 200 mg/kg by 25-59% (p < .05), and enhance the phenol red secretion (p < .05), while the ethyl acetate extract showed little effect. These results indicate liquiritin apioside and liquiritin are the major antitussive and expectorant compounds of licorice. Their antitussive effects depend on both peripheral and central mechanisms.

Permeability through the Caco-2 cell monolayer of 42 bioactive compounds in the TCM formula Gegen-Qinlian Decoction by liquid chromatography tandem mass spectrometry analysis

Caco-2 cell monolayer model was used to evaluate the intestinal permeability of 42 bioactive compounds in the famous traditional Chinese medicine (TCM) formula Gegen-Qinlian Decoction (GQD). These compounds include alkaloids, flavonoids and glycosides, triterpenoid saponins, and coumarins. Their transportations across the cell monolayers in the forms of herb extract and formula extract were monitored by liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS) analysis. Most alkaloids from Huang-Lian; flavonoid C-glycosides from Ge-Gen and Huang-Qin; O-glycosides from Ge-Gen, Huang-Qin and Gan-Cao; O-glucuronides from Huang-Qin; and coumarins from Gan-Cao exhibited favorable permeability. Their P_AB values were >1.05×10^-5cm/s, and efflux ratios (ER, P_BA/P_AB) were≤1.0. In contrast, triterpenoid saponins showed poor permeability (P_AB≤1.50×10^-6cm/s, ER≤1.5), indicating a paracellular diffusion mechanism. Furthermore, GQD could remarkably improve the intestinal transport of alkaloids in Huang-Lian, flavonoid C-glycosides in Ge-Gen, as well as coumarins and flavonoid O-glycosides in Gan-Cao. These results indicate herb-herb interactions in GQD.

Identification and analysis of chemical constituents and rat serum metabolites in Suan-Zao-Ren granule using ultra high performance liquid chromatography quadrupole time-of-flight mass spectrometry combined with multiple data processing approaches

Suan-Zao-Ren granule is widely used to treat insomnia in China. However, because of the complexity and diversity of the chemical compositions in traditional Chinese medicine formula, the comprehensive analysis of constituents in vitro and in vivo is rather difficult. In our study, an ultra high performance liquid chromatography with quadrupole time-of-flight mass spectrometry and the PeakView® software, which uses multiple data processing approaches including product ion filter, neutral loss filter, and mass defect filter, method was developed to characterize the ingredients and rat serum metabolites in Suan-Zao-Ren granule. A total of 101 constituents were detected in vitro. Under the same analysis conditions, 68 constituents were characterized in rat serum, including 35 prototype components and 33 metabolites. The metabolic pathways of main components were also illustrated. Among them, the metabolic pathways of timosaponin AI were firstly revealed. The bioactive compounds mainly underwent the phase I metabolic pathways including hydroxylation, oxidation, hydrolysis, and phase II metabolic pathways including sulfate conjugation, glucuronide conjugation, cysteine conjugation, acetycysteine conjugation, and glutathione conjugation. In conclusion, our results showed that this analysis approach was extremely useful for the in-depth pharmacological research of Suan-Zao-Ren granule and provided a chemical basis for its rational.

A Systematic Strategy for Discovering a Therapeutic Drug for Alzheimer's Disease and Its Target Molecule

Natural medicines are attractive sources of leading compounds that can be used as interventions for neurodegenerative disorders. The complexity of their chemical components and undetermined bio-metabolism have greatly hindered both the use of natural medicines and the identification of their active constituents. Here, we report a systematic strategy for evaluating the bioactive candidates in natural medicines used for Alzheimer's disease (AD). We found that Drynaria Rhizome could enhance memory function and ameliorate AD pathologies in 5XFAD mice. Biochemical analysis led to the identification of the bio-effective metabolites that are transferred to the brain, namely, naringenin and its glucuronides. To explore the mechanism of action, we combined the drug affinity responsive target stability with immunoprecipitation-liquid chromatography/mass spectrometry analysis, identifying the collapsin response mediator protein 2 protein as a target of naringenin. Our study indicates that biochemical analysis coupled with pharmacological methods can be used in the search for new targets for AD intervention.

Understanding the Molecular Mechanisms of the Interplay Between Herbal Medicines and Gut Microbiota

Herbal medicines (HMs) are much appreciated for their significant contribution to human survival and reproduction by remedial and prophylactic management of diseases. Defining the scientific basis of HMs will substantiate their value and promote their modernization. Ever-increasing evidence suggests that gut microbiota plays a crucial role in HM therapy by complicated interplay with HM components. This interplay includes such activities as: gut microbiota biotransforming HM chemicals into metabolites that harbor different bioavailability and bioactivity/toxicity from their precursors; HM chemicals improving the composition of gut microbiota, consequently ameliorating its dysfunction as well as associated pathological conditions; and gut microbiota mediating the interactions (synergistic and antagonistic) between the multiple chemicals in HMs. More advanced experimental designs are recommended for future study, such as overall chemical characterization of gut microbiota-metabolized HMs, direct microbial analysis of HM-targeted gut microbiota, and precise gut microbiota research model development. The outcomes of such research can further elucidate the interactions between HMs and gut microbiota, thereby opening a new window for defining the scientific basis of HMs and for guiding HM-based drug discovery.

Identification, bioactivity evaluation and pharmacokinetics of multiple components in rat serum after oral administration of Xian-Ling-Gu-Bao capsule by ultra performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry

The Xian-Ling-Gu-Bao capsule (XLGB) is a famous traditional Chinese medicine prescription (TCMP), which has proven effective in osteoporosis treatment. However, due to the lack of a dynamic XLGB profile, the in vivo pharmacokinetics of multiple bioactive components within this medicine remains unknown. In the present study, ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC/Q-TOF-MS) identified a total of eighteen prototypes (using reference standards) in rat serum after oral administration of XLGB. These prototypes were subsequently evaluated to ascertain their effects on the proliferation and alkaline phosphatase activity of UMR106 cells and the adipogenesis of 3T3-L1 cells. Furthermore, a rapid and sensitive UPLC/Q-TOF-MS method was developed and validated for simultaneous quantitative analysis of 11 prototypes in rat serum. Chromatographic separation was achieved using a Waters Acquity BEH C18 column (2.1×100mm, 1.7μm) and linear gradient elution employing a mobile phase consisting of water and acetonitrile (both containing 0.1% formic acid). All calibration curves showed excellent linearity (r²>0.99) within the sampling ranges considered. The assay was accurate, precise and reproducible, as demonstrated by the obtained intra- and inter-day precisions (less than 12.3%) and accuracies (between -12.7% and 11.0%), and the matrix effects, extraction recoveries and stabilities were all satisfactory. Moreover, pharmacokinetic parameters were calculated from the plasma concentration-time data. Compared to single-compound dosing, significantly enhanced responses were obtained when several analytes were administered simultaneously, indicating possible drug-drug interactions among the complex ingredients of TCMP. This work provides an experimental baseline regarding the clinical applications and medicinal effectiveness of XLGB in the treatment of osteoporosis.

Compound to Extract to Formulation: a knowledge-transmitting approach for metabolites identification of Gegen-Qinlian Decoction, a traditional Chinese medicine formula

Herbal medicines usually contain a large group of chemical components, which may be transformed into more complex metabolites in vivo. In this study, we proposed a knowledge-transmitting strategy for metabolites identification of compound formulas. Gegen-Qinlian Decoction (GQD) is a classical formula in traditional Chinese medicine (TCM). It is widely used to treat diarrhea and diabetes in clinical practice. However, only tens of metabolites could be detected using conventional approaches. To comprehensively identify the metabolites of GQD, a “compound to extract to formulation” strategy was established in this study. The metabolic pathways of single representative constituents in GQD were studied, and the metabolic rules were transmitted to chemically similar compounds in herbal extracts. After screening diversified metabolites from herb extracts, the knowledge was summarized to identify the metabolites of GQD. Tandem mass spectrometry (MSⁿ), fragment-based scan (NL, PRE), and selected reaction monitoring (SRM) were employed to identify, screen, and monitor the metabolites, respectively. Using this strategy, we detected 131 GQD metabolites (85 were newly generated) in rats biofluids. Among them, 112 metabolites could be detected when GQD was orally administered at a clinical dosage (12.5 g/kg). This strategy could be used for systematic metabolites identification of complex Chinese medicine formulas.

HSCCC-based strategy for preparative separation of in vivo metabolites after administration of an herbal medicine: Saussurea laniceps, a case study

This paper reports a novel strategy based on high-speed counter-current chromatography (HSCCC) technique to separate in vivo metabolites from refined extract of urine after administration of an herbal medicine. Saussurea laniceps (SL) was chosen as a model herbal medicine to be used to test the feasibility of our proposed strategy. This strategy succeeded in the case of separating four in vivo metabolites of SL from the urine of rats. Briefly, after oral administration of SL extract to three rats for ten days (2.0 g/kg/d), 269.1 mg of umbelliferone glucuronide (M1, purity, 92.5%), 432.5 mg of scopoletin glucuronide (M2, purity, 93.2%), 221.4 mg of scopoletin glucuronide (M3, purity, 92.9%) and 319.0 mg of scopoletin glucuronide (M4, purity, 90.4%) were separated from 420 mL of the rat urine by HSCCC using a two-phase solvent system composed of methyl tert-butyl ether-n-butanol-acetonitrile-water (MTBE-n-BuOH-ACN-H2O) at a volume ratio of 10:30:11:49. The chemical structures of the four metabolites, M1 to M4, were confirmed by MS and (1)H, (13)C NMR. As far as we know, this is the first report of the successful separation of in vivo metabolites by HSCCC after administration of an herbal medicine.

CRF receptor 1 antagonism and brain distribution of active components contribute to the ameliorative effect of rikkunshito on stress-induced anorexia

Rikkunshito (RKT), a Kampo medicine, has been reported to show an ameliorative effect on sustained hypophagia after novelty stress exposure in aged mice through serotonin 2C receptor (5-HT_2CR) antagonism. We aimed to determine (1) whether the activation of anorexigenic neurons, corticotropin-releasing factor (CRF), and pro-opiomelanocortin (POMC) neurons, is involved in the initiation of hypophagia induced by novelty stress in aged mice; (2) whether the ameliorative effect of RKT is associated with CRF and POMC neurons and downstream signal transduction; and (3) the plasma and brain distribution of the active components of RKT. The administration of RKT or 5-HT_2CR, CRF receptor 1 (CRFR1), and melanocortin-4 receptor antagonists significantly restored the decreased food intake observed in aged male C57BL/6 mice in the early stage after novelty stress exposure. Seven components of RKT exhibited antagonistic activity against CRFR1. Hesperetin and isoliquiritigenin, which showed antagonistic effects against both CRFR1 and 5-HT_2CR, were distributed in the plasma and brain of male Sprague-Dawley rats after a single oral administration of RKT. In conclusion, the ameliorative effect of RKT in this model is assumed to be at least partly due to brain-distributed active components possessing 5-HT_2CR and CRFR1 antagonistic activities.

Bioactive Constituents of Glycyrrhiza uralensis (Licorice): Discovery of the Effective Components of a Traditional Herbal Medicine

Traditional herbal medicines have been reported to possess significant bioactivities. In this investigation, a combined strategy using both phytochemical and biological approaches was conducted to discern the effective components of licorice, a widely used herbal medicine. Altogether, 122 compounds (1-122), including six new structures (1-6), were isolated and identified from the roots and rhizomes of Glycyrrhiza uralensis (licorice). These compounds were then screened using 11 cell- and enzyme-based bioassay methods, including Nrf2 activation, NO inhibition, NF-κB inhibition, H1N1 virus inhibition, cytotoxicity for cancer cells (HepG2, SW480, A549, MCF7), PTP1B inhibition, tyrosinase inhibition, and AChE inhibition. A number of bioactive compounds, particularly isoprenylated phenolics, were found for the first time. Echinatin (7), a potent Nrf2 activator, was selected as an example for further biological work. It attenuated CCl4-induced liver damage in mice (5 or 10 mg/kg, ip) and thus is responsible, at least in part, for the hepatoprotective activity of licorice.

Efficient and selective glucosylation of prenylated phenolic compounds by Mucor hiemalis

Mucor hiemaliscould efficiently and selectively catalyze β-O-glucosylation of the isoprenyl-neighboring hydroxyl group of prenylated phenolic compounds.

Metabolite identification and pharmacokinetic study of Lamiophlomis rotata in rats

An ultra-high performance liquid chromatography coupled with time-of-flight mass spectrometry technique and a subsequent LC-MS/MS method were developed for metabolite profile study of Lamiophlomis rotata extract after its oral administration.