Xinchi Feng

Potential drug interactions associated with glycyrrhizin and glycyrrhetinic acid

Abstract Glycyrrhizin (GZ), the main active component of licorice, is a widely used therapeutic in the clinic. Depending on the disease, the treatment may involve a long course of high dose GZ. Another component of licorice, glycyrrhetinic acid (GA), is the main active metabolite of GZ and is thought to be responsible for the majority of the pharmacological properties of GZ. Therefore, GZ and GA are both used for therapeutic purposes. In addition, GZ and GA are also widely used to sweeten and flavor foods. Due to this widespread, multifaceted use of these substances, potential drug interactions with GZ and GA have recently gained attention. Along these lines, this review covers the known effects of GZ and GA on drug-metabolizing enzymes and efflux transporters. We conclude that both GZ and GA may have an effect on the activity of CYPs. For example, GZ may induce CYP3A activity through activation of PXR. Also, GZ and GA may affect glucuronidation in rats and humans. Furthermore, 18β-GA is a potent inhibitor of P-gp, while GZ and GA are inhibitors of MRP1, MRP2 and BCRP. The pharmacokinetics and pharmacodynamics of many medications may be altered when used concurrently with GZ or GA, which is also covered in this review. Overall, GZ, GA or related products should be taken with caution when taken with additional medications due to the possible drug interactions.

Metabolites identification of berberine in rats using ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry

HIGHLIGHTSThe metabolism of BBR in rats was explored by UPLC‐ESI‐Q‐TOF‐MS method with Metabolynx™ software and mass defect filter technique.A simple and reliable five‐step strategy was established to comprehensively investigate the metabolites of BBR.The 97 metabolites of BBR were identified in rat biological samples.The main metabolic pathways of BBR were demethylation, demethylenation, hydroxylation, reduction, and subsequent conjugation reactions. ABSTRACT Berberine (BBR), the principle component for many medicinal plants such as Coptis chinensis Franch., Phellodendron chinense Schneid., and Mahonia bealei (Fort.) Carr., possesses diverse pharmacological activities, including anti‐bacterial, anti‐inflammatory, antitumor, hypolipidemic and antidiabetic activities. In this study, a rapid and reliable method using a five‐step strategy based on the ultra‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry (UPLC/Q‐TOF‐MS), and metabolynx™ software with mass defect filter (MDF) technique was developed to investigate the metabolism of BBR. Plasma, bile, urine and feces samples were collected from rats after oral administration of BBR with a dose of 100 mg/kg/day for three consecutive days and analyzed to characterize the metabolic profile of BBR. By comparing the molecular weights and MS fragmentations of the metabolites with those of the parent drug and reference standards, a total of 97 metabolites were identified, including 68 metabolites in urine, 45 metabolites in plasma, 44 metabolites in bile and 41 metabolites in feces. Demethylation, demethylenation, reduction, hydroxylation, and subsequent glucuronidation, sulfation and methylation were the major metabolic pathways of BBR in vivo.

The metabolism of berberine and its contribution to the pharmacological effects

Abstract Berberine, a bioactive alkaloid isolated from several herbal substances, possesses multiple pharmacological effects, including antimicrobial, antidiabetic, anticancer activities. Meanwhile, berberine undergoes extensive metabolism after oral administration which results in its extremely low plasma exposure. Therefore, it is believed that the metabolites of berberine also contribute a lot to its pharmacological effects. Along these lines, this review covers the metabolism studies of berberine in terms of its metabolic pathways and metabolic organs based on the identified metabolites, and it also covers the pharmacological activities of its active metabolites. In brief, the predominant metabolic pathways of berberine are demethylation, demethylenation, reduction, hydroxylation and subsequent conjugation in vivo. Active metabolites such as columbamine, berberrubine and demethyleneberberine also exhibit similar pharmacological effects by comparison with berberine, such as antioxidant, anti-inflammatory, antitumor, antimicrobial, hepatoprotective, neuroprotective, hypolipidemic and hypoglycemic effects. Overall, berberine together with its metabolites formed the material basis of berberine in vivo.

Metabolic profiles of physalin A in rats using ultra-high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry

Physalin A, one of the major active components isolated from the calyces of Physalis alkekengi var. franchetii is considered to be a promising natural product due to its anti-inflammatory and excellent antitumor activities. Until now, only one paper is available from our group concerning identification of two sulfonate metabolites from rat feces after physalin A treatment. All the other researches related to physalin A were focused on its extraction, separation and biological activities. In this research, a rapid and reliable ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS/MS) method was developed and employed for the comprehensive study of the metabolism of physalin A in vivo for the first time. A total of 24 proposed metabolites were identified in plasma, bile, urine and feces of rats after oral administration of physalin A. The results indicated that sulfonation, reduction and hydroxylation were the major metabolic pathways of physalin A in vivo. Furthermore, this research provides scientific and reliable support for full understanding of the metabolism of physalin A and the results could help to elucidate the safety and efficacy of physalin A, as well as other physalins.

Identification of berberrubine metabolites in rats by using ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry

Berberrubine, an isoquinoline alkaloid isolated from many medicinal plants, possesses diverse pharmacological activities, including glucose-lowering, lipid-lowering, anti-inflammatory, and anti-tumor effects. This study aimed to investigate the metabolic profile of berberrubine in vivo. Therefore, a rapid and reliable method using the ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and metabolynx™ software with mass defect filter (MDF) technique was developed. Plasma, bile, urine and feces samples were collected from rats after oral administration of berberrubine with a dose of 30.0mg/kg and analyzed to characterize the metabolites of berberrubine in vivo for the first time. A total of 57 metabolites were identified, including 54 metabolites in urine, 39 metabolites in plasma, 28 metabolites in bile and 18 metabolites in feces. The results indicated that demethylenation, reduction, hydroxylation, demethylation, glucuronidation, and sulfation were the major metabolic pathways of berberrubine in vivo.

Insights into the intestinal bacterial metabolism of flavonoids and the bioactivities of their microbe-derived ring cleavage metabolites

Abstract Flavonoids are a group of phytochemicals widely distributed in plants, fruits, and vegetables that possess numerous bioactivities. After oral administration, flavonoids can be metabolized by the intestinal bacteria into a wide range of low-molecular-weight phenolic acids. In this review, the intestinal bacterial metabolic pathways of different flavonoids (flavones, isoflavones, flavonols, flavanones, and chalcones) and the bioactivities of their microbe-derived ring cleavage metabolites are summarized. Flavonoids undergo different intestinal bacterial metabolic reactions, depending on the characteristics of their structure. Free hydroxyl groups, especially 5 and 4’ free hydroxyl groups play significant roles in fission metabolism. Microbe-derived ring cleavage metabolites such as 3,4-dihydroxyphenylacetic acid (3,4-DHPAA) and 3,4-dihydroxytoluene (3,4-DHT) possess various bioactivities including antioxidant, anti-inflammatory, antidiabetic, neuroprotective, and anti-colon cancer effects. Also, the intestinal bacteria associated with the bacterial metabolism of flavonoids are covered in this review.

A new phenone from the roots of Paeonia suffruticosa Andrews

Abstract Thirteen phenones were obtained from the 70% ethanol extract of Paeonia suffruticosa Andrews. Their structures were determined on the basis of chemical methods and spectral data. Among them, compound 1 was identified as a new compound, and compounds 5 and 13 were obtained from genus Paeonia for the first time. The inhibitory effects of isolated compounds (1–12) on nitric oxide (NO) production in lipopolysaccharide-activated macrophages were evaluated, and NO production was suppressed significantly by compound 7.

Two new lignans from the aerial part of Vitex negundo

Abstract A new phenyldihydronaphthalene-type lignan, (3R,4S)-6-hydroxy-4-(4-hydroxy- 3-methoxyphenyl)-5,7-dimethoxy-3,4-dihydro-2-naphthaldehyde-3a-O-β-d-glucopyranoside (1), and a new phenylnaphthalene-type lignan, 6,7,4′-trihydroxy-3′-methoxy-2,3- cycloligna-1,4-dien-2a,3a-olide (2), along with 10-known lignan derivatives (3–12) were isolated from the aerial part of Vitex negundo var. heterophylla. Their structures were established by comprehensive 1D- and 2D-NMR spectroscopic analyses.

Identification of absorbed constituents and in vivo metabolites in rats after oral administration of Physalisalkekengi var. franchetii by ultrahigh-pressure liquid chromatography quadrupole time-of-flight mass spectrometry

The calyces of Physalis alkekengi var. franchetii (Chinese Lantern, JDL) are well-known as traditional Chinese medicine owing to its various therapeutic effects. However, the bioactive constituents responsible for the pharmacological effects of JDL and their metabolites in vivo are still unclear to date. In this paper, an ultra-high-pressure liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS/MS) method was established to identify absorbed constituents and in vivo metabolites in rat biological fluids after oral administration of JDL. Based on the proposed strategy, 33 compounds were observed in dosed rat biosamples. Twelve of 33 compounds were indicated as prototype components of JDL, and 21 compounds were predicted to be metabolites of JDL. Finally, the metabolic pathways were proposed, which were glucuronidation, sulfation, methylation and dehydroxylation for flavonoid constituents and sulfonation and hydroxylation for physalin consitituents. This is the first systematic study on the absorbed constituents and metabolic profiling of JDL and will provide a useful template for screening and characterizing the ingredients and metabolites of traditional Chinese medicine.

Characterization of the In Vivo and In Vitro Metabolites of Linarin in Rat Biosamples and Intestinal Flora Using Ultra-High Performance Liquid Chromatography Coupled with Quadrupole Time-of-Flight Tandem Mass Spectrometry

Linarin, a flavone glycoside, is considered to be a promising natural product due to its diverse pharmacological activities, including analgesic, antipyretic, anti-inflammatory and hepatoprotective activities. In this research, the metabolites of linarin in rat intestinal flora and biosamples were characterized using ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS/MS). Three ring cleavage metabolites (4-hydroxybenzoic acid, 4-hydroxy benzaldehyde and phloroglucinol) were detected after linarin was incubated with rat intestinal flora. A total of 17 metabolites, including one ring cleavage metabolite (phloroglucinol), were identified in rat biosamples after oral administration of linarin. These results indicate that linarin was able to undergo ring fission metabolism in intestinal flora and that hydrolysis, demethylation, glucuronidation, sulfation, glycosylation, methylation and ring cleavage were the major metabolic pathways. This study provides scientific support for the understanding of the metabolism of linarin and contributes to the further development of linarin as a drug candidate.