Urinary biomarker and treatment mechanism of Rhizoma Alismatis on hyperlipidemia

Rhizoma Alismatis (RA), a diuretic in Asia and Europe, was found to possess anti‐hyperlipidemic activity. Since the biomarkers and mechanisms of RA in the treatment of hyperlipidemia are inadequate, ultra‐performance liquid chromatography coupled with quadrupole time‐of‐flight synapt high‐definition mass spectrometry and multivariate data analysis were employed to investigate the urinary metabolomics of RA on hyperlipidemic rats induced by high‐fat diet. The metabolic profile of RA‐treated hyperlipidemic group located between control and diet‐induced hyperlipidemic groups. Nineteen metabolites with significant fluctuations were identified as potential biomarkers related to the hyperlipidemia and anti‐hyperlipidemia of RA using partial least‐squares‐discriminate analysis, heatmap analysis and correlation coefficient analysis. The fluctuations of these biomarkers represented disturbances in amino acid metabolism, purine metabolism, pyrimidine metabolism and energy metabolism. After RA treatment, these perturbed metabolites were restored to normal or nearly normal levels. RA can alleviate high‐fat diet‐induced dysfunctions in these metabolic pathways.     

Identification of metabolites of Helicid in vivo using ultra‐high performance liquid chromatography‐quadrupole time‐of‐flight mass spectrometry

Helicid is an active natural aromatic phenolic glycoside ingredient originating from a well‐known traditional Chinese herbal medicine and has the significant effects of sedative hypnosis, anti‐inflammatory analgesia and antidepressant. In this study, we analyzed the potential metabolites of Helicid in rats by multiple mass defect filter and dynamic background subtraction in ultra‐high‐performance liquid chromatography–quadrupole time‐of‐flight mass spectrometry (UHPLC‐Q‐TOF‐MS). Moreover, we used a novel data processing method, ‘key product ions’, to rapidly detect and identify metabolites as an assistant tool. MetabolitePilot™ 2.0 software and PeakView™ 2.2 software were used for analyzing metabolites. Twenty metabolites of Helicid (including 15 phase I metabolites and five phase II metabolites) were detected by comparison with the blank samples. The biotransformation route of Helicid was identified as demethylation, oxidation, dehydroxylation, hydrogenation, decarbonylation, glucuronide conjugation and methylation. This is the first study simultaneously detecting and identifying Helicid metabolism in rats employing UHPLC‐Q‐TOF‐MS technology. This experiment not only proposed a method for rapidly detecting and identifying metabolites, but also provided useful information for further study of the pharmacology and mechanism of Helicid in vivo. Furthermore, it provided an effective method for the analysis of other aromatic phenolic glycosides metabolic components in vivo.     

Analysis of the metabolic profile of parishin by ultra‐performance liquid chromatography/quadrupole‐time of flight mass spectrometry

Parishin is a dominant active ingredient originating from Gastrodia elata Blume, and has good neuroprotective effects against brain disorders. In the present study, the metabolic profile of parishin by in vitro and in vivo experiments was investigated using ultra‐high performance liquid chromatography coupled with quadrupole–time of flight mass spectrometry (UHPLC/Q‐TOF MS) combined with an automated MS^E technique. By comparison with reference compounds, accurate mass measurement, the characteristic fragmentation patterns of the parent drug parishin and gastrodin and relevant bio‐transformation knowledge, 14 metabolites (seven hydrolyzates and seven derivatives of gastrodin) were detected and identified in rat plasma and urine after intragastric administration of parishin, including processes of hydrolyzation, oxidation, sulfation and glucuronidation. According to the proposed metabolic pathways of parishin, in vitro hydrolytic experiments and metabolic study of gastrodin in rat plasma, it can be inferred that parishin mainly functions as a prodrug and undergoes hydrolysis before being absorbed into the blood. The hydrolyzate, mainly gastrodin, was involved in further metabolism, which was responsible for pharmacological activities of parishin. In conclusion, this work provides valuable information on parishin metabolism using a rapid and reliable UHPLC/Q‐TOF MS method, which could be widely used for the metabolic investigation of natural product. Copyright © 2015 John Wiley & Sons, Ltd.     

Urinary metabolomics of complete Freund's adjuvant‐induced hyperalgesia in rats

The aim of this study was to demonstrate the differences of metabolomics changes in a hyperalgesia model and find potent biomarkers of hyperalgesia. Seven rats were placed in metabolic cages. An emulsion containing 500 μg of Complete Freund's adjuvant (CFA) was used to induce hyperalgesia. Urine samples were collected prior to the injection of CFA and on post‐injection days 1, 3 and 7. Ultraperformance liquid chromatography, coupled with quadrupole‐time‐of‐flight mass spectrometry (UHPLC‐Q‐TOF/MS), was used for a quantitative analysis of urinary metabolic changes in the CFA‐induced hyperalgesia model. Differences between the metabolic profiles of the rats in the four groups were analyzed using partial least squares discriminant analysis. Thirty‐four potential urine metabolite biomarkers were identified, which changed in a trend similar to the pain threshold. These potential biomarkers were involved in 11 metabolic pathways, as follows: alanine, aspartate, and glutamate metabolism; ascorbate and aldarate metabolism; glycerolipid metabolism; glycerophospholipid metabolism; histidine metabolism; phenylalanine metabolism; sphingolipid metabolism; tryptophan metabolism; tyrosine metabolism; valine, leucine and isoleucine biosynthesis; and vitamin B6 metabolism. These results may improve our understanding of hyperalgesia and provide a basis for the clinical diagnosis of hyperalgesia.     

Strategy for rapid screening of antioxidant and anti‐inflammatory active ingredients in Gynura procumbens (Lour.) Merr. based on UHPLC–Q‐TOF–MS/MS and characteristic ion filtration

Gynura procumbens (Lour.) Merr. is traditionally used as a raw material for making dumplings or steamed stuffed buns, and its fresh leaves are boiled with water for tea. Herein, we established an ultra‐high–performance liquid chromatography–quadrupole time‐of‐flight mass spectrometry (UHPLC–Q‐TOF–MS/MS) combined with characteristic ion filtration (CIF) strategy to rapidly screen active ingredients with antioxidant and anti‐inflammatory properties in G. procumbens. This strategy involved screening the active part of G. procumbens using antioxidation and anti‐inflammatory activity assays; discovering the active compounds by speculating on the active site's chemical composition by UHPLC–Q‐TOF–MS/MS plus CIF; and verifying the active compounds' activities. The ethyl acetate extract (EEAF) of G. procumbens was the major active site. Eighty‐one compounds were identified from the EEAF using UHPLC–Q‐TOF–MS/MS plus CIF. Furthermore, polyphenols such as cynarine, isochlorogenic acids A and isochlorogenic acids C have excellent antioxidizing and anti‐inflammatory activities. This study provides a practical strategy for rapid in vitro screening of the antioxidizing and anti‐inflammatory activities of traditional vegetables and herbs and identification of active ingredients.     

Protective effects of timosaponin BII on oxidative stress damage in PC12 cells based on metabolomics

Peroxide and oxygen free radicals are some of the causes of oxidative stress in brain tissue, and could lead to the change of brain structure and function. In addition, oxidative damage is one of the most important causes of the aging of the vast majority of tissues. The aim of this study is to investigate the protective effect of timosaponin BII on oxidative stress damage of PC12 induced by H₂O₂ using metabolomics based on the UHPLC‐Q‐TOF‐MS technique. Partial least‐squares discriminant analysis method was used to identify 35 metabolites as decisive marker compounds in a preliminary interpretation of the mechanism of the antioxidative effect of timosaponin BII. The majority of these metabolites are involved in the glutathione metabolism, amino acid metabolism, sphingolipid and glycerophospholipid metabolism. Our results suggest that timosaponin BII demonstrates systematic antioxidant effects in the PC12 oxidative damage cell model via the regulation of multiple metabolic pathways. These findings provide insight into the pathophysiological mechanisms underlying oxidative stress damage and suggest innovative and effective treatments for this disorder, providing a reliable basis for the development of novel therapeutic target in timosaponin BII treatment of oxidative stress.     

Metabolism studies on prim‐O‐glucosylcimifugin and cimifugin in human liver microsomes by ultra‐performance liquid chromatography quadrupole time‐of‐flight mass spectrometry

Prim‐O‐glucosylcimifugin (PGCN) and cimifugin (CN) are major constituents of Radix Saposhnikoviae that have antipyretic, analgesic and anti‐inflammatory pharmacological activities. However, there were few reports with respect to the metabolism of PGCN and CN in vitro. In this paper, we describe a strategy using ultra‐performance liquid chromatography quadrupole time‐of‐flight mass spectrometry (UPLC‐Q‐TOF‐MS) for fast analysis of the metabolic profile of PGCN and CN in human liver microsomes. In total, five phase I metabolites of PGCN, seven phase I metabolites and two phase II metabolites of CN were identified in the incubation of human liver microsomes. The results revealed that the main phase I metabolic pathways of PGCN were hydroxylation and hydrolysis reactions. The phase I metabolic pathways of CN were found to be hydroxylation, demethylation and dehydrogenation. Meanwhile, the results indicated that O‐glucuronidation was the major metabolic pathway of CN in phase II metabolism. The specific UDP‐glucuronosyltransferase (UGT) enzymes responsible for CN glucuronidation metabolites were identified using recombinant UGT enzymes. The results indicated that UGT1A1, UGT1A9, UGT2B4 and UGT2B7 might play major roles in the glucuronidation of CN. Overall, this study may be useful for the investigation of metabolic mechanism of PGCN and CN, and it can provide reference and evidence for further pharmacodynamic experiments. Copyright © 2016 John Wiley & Sons, Ltd.     

Metabolic analysis of the antidepressive effects of Yangxinshi Tablet in a vascular depression model in mice

In recent years, vascular depression has become the focus of international attention. Yangxinshi Tablet (YXST) is usually used in cthe linic for the treatment of arrhythmia and heart failure, but we found that it also has antidepressive effects. The objective of the study was to identify biomarkers related to vascular depression in hippocampus and explore the antidepressive effects of YXST on the mouse model. Untargeted metabolomics based on UHPLC‐Q‐TOF/MS was applied to identify significantly differential biomarkers between the model group and control group. Unsupervised principal component analysis (PCA) was used to scan the tendency of groups and partial least squares‐discriminant analysis (PLS‐DA) to distinguish between the vascular depressive mice and the sham. PCA stores showed clear differences in metabolism between the vascular depressive mice and sham groups. The PLS‐DA model exhibited 38 metabolites as the biomarkers to distinguish the vascular depressive mice and the sham. Further, YXST significantly regulated 22 metabolites to normal levels. The results suggested that YXST has a comprehensive antidepressive effect on vascular depression via regulation of multiple metabolic pathways including amino acid, the tricarboxylic acid cycle and phosphoglyceride metabolisms. These findings provide insight into the pathophysiological mechanism underlying vascular depression and the mechanism of YXST.     

A comprehensive in vitro and in vivo metabolism study of hydroxysafflor yellow A

As the most important marker component in Carthamus tinctorius L., hydroxysafflor yellow A (HSYA) was widely used in the prevention and treatment of cardiovascular diseases, due to its effect of improving blood supply, suppressing oxidative stress, and protecting against ischemia/reperfusion. In this paper, both an in vitro microsomal incubation and an in vivo animal experiment were conducted, along with an LC‐Q‐TOF/MS instrument and a 3‐step protocol, to further explore the metabolism of HSYA. As a result, a total of 10 metabolites were searched and tentatively identified in plasma, urine, and feces after intravenous administration of HSYA to male rats, although no obvious biotransformation was found in the simulated rat liver microsomal system. The metabolites detected involving both phase I and phase II metabolism including dehydration, deglycosylation, methylation, and glucuronic acid conjugation. A few of the metabolites underwent more than one‐step metabolic reactions, and some have not been reported before. The study would contribute to a further understanding of the metabolism of HSYA and provide scientific evidence for its pharmacodynamic mechanism research and clinical use.     

Metabolic profiles of neratinib in rat by using ultra‐high‐performance liquid chromatography coupled with diode array detector and Q‐Exactive Orbitrap tandem mass spectrometry

Neratinib is a tyrosine kinase inhibitor that has been approved by the US Food and Drug Administration for the treatment of breast cancer. However, its metabolism remains unknown. This study was carried out to investigate the in vitro and in vivo metabolism of neratinib using an UHPLC‐DAD‐Q Exactive Orbitrap‐MS instrument with dd‐MS² on‐line data acquisition mode. The post‐acquisition data was processed using MetWorks software. Under the current conditions, a total of 12 metabolites were detected and structurally identified based on their accurate masses, fragment ions and chromatographic retention times. Among these metabolites, M3, M10 and M12 were unambiguously identified using chemically synthesized reference standards. M6 and M7 (GSH conjugates) were the major metabolites. The metabolic pathways of neratinib were proposed accordingly. Our findings suggested that neratinib was mainly metabolized via O‐dealkylation (M3), oxygenation (M8), N‐demethylation (M10), N‐oxygenation (M12), GSH conjugation (M1, M2, M4, M5, M6 and M7) and N‐acetylcysteine conjugation (M9 and M11). The α,β‐unsaturated ketone was the major metabolic site and GSH conjugation was the predominant metabolic pathway. In conclusion, this study provided valuable metabolic data and would benefit the assessment of the contributions to the overall activity or toxicity from the key metabolites.     

Identification of the absorbed components and metabolites of modified Huo Luo Xiao Ling Dan in rat plasma by UHPLC‐Q‐TOF/MS/MS

To reveal the material basis of Huo Luo Xiao Ling Dan (HLXLD), a sensitive and selective ultra‐high performance liquid chromatography coupled with quadrupole‐time‐of‐flight mass spectrometry (UHPLC‐Q‐TOF/MS) method was developed to identify the absorbed components and metabolites in rat plasma after oral administration of HLXLD. The plasma samples were pretreated by liquid–liquid extraction and separated on a Shim‐pack XR‐ODS C₁₈ column (75 × 3.0 mm, 2.2 μm) using a gradient elution program. With the optimized conditions and single sample injection of each positive or negative ion mode, a total of 109 compounds, including 78 prototype compounds and 31 metabolites, were identified or tentatively characterized. The fragmentation patterns of representative compounds were illustrated as well. The results indicated that aromatization and hydration were the main metabolic pathways of lactones and tanshinone‐related metabolites; demethylation and oxidation were the major metabolic pathways of alkaloid‐related compounds; methylation and sulfation were the main metabolic pathways of phenolic acid‐related metabolites. It is concluded the developed UHPLC‐Q‐TOF/MS method with high sensitivity and resolution is suitable for identifying and characterizing the absorbed components and metabolites of HLXLD, and the results will provide essential data for further studying the relationship between the chemical components and pharmacological activity of HLXLD.     

Characterization of metabolites of sweroside in rat urine using ultra‐high‐performance liquid chromatography combined with electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry and NMR spectroscopy

Sweroside, a major active iridoid in Swertia pseudochinensis Hara, is recognized as an effective agent in the treatment of liver injury. Based on previous reports, the relatively short half‐life (64 min) and poor bioavailability (approximately 0.31%) in rats suggested that not only sweroside itself but also its metabolites could be responsible for the observed hepato‐protective effect. However, few studies have been carried out on the metabolism of sweroside. Therefore, the present study aimed at identifying the metabolites of sweroside in rat urine after a single oral dose (100 mg/kg). With ultra‐high‐performance liquid chromatography coupled with electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry (UHPLC/Q‐TOF‐MS), the metabolic profile revealed 11 metabolites in rat urine, including phase I, phase II and aglycone‐related products. The chemical structures of metabolites were proposed based on accurate mass measurements of protonated or deprotonated molecules and their fragmentation patterns. Our findings showed that the aglycone of sweroside (M05) and its glucuronide conjugate (M06) were principal circulating metabolites in rats. While several other metabolic transformations, occurring via reduction, N‐heterocyclization and N‐acetylation after deglycosylation, were also observed. Two metabolites (M05 and M06) were isolated from the rat urine for structural elucidation and identifcation of reaction sites. Both M05 and M06 were characterized by ¹H, ¹³C and two‐dimensional nuclear magnetic resonance (NMR) spectroscopy. UHPLC/Q‐TOF‐MS analysis has provided an important analytical platform to gather metabolic profile of sweroside. Copyright © 2014 John Wiley & Sons, Ltd.     

Metabolic profiles and pharmacokinetics of goitrin in rats through liquid chromatography combined with electrospray ionization–tandem mass spectrometry

Several chemical and biological studies have revealed R,S‐goitrin as the main bioactive constituent of Isatis indigotica Fort., responsible for antiviral antiendotoxin activity; however, few pharmacokinetic studies have been conducted. To comprehend the kinetics of R,S‐goitrin and promote its curative application, a rapid and sensitive UHPLC–MS/MS method was developed. The selected reaction monitoring transitions were m/z 130.0 → 70.0 for R,S‐goitrin and m/z 181.1 → 124.0 for the internal standard in a positive‐ion mode. The established UHPLC–MS/MS method achieved good linearity for R,S‐goitrin at 10–2000 ng/mL. The intra‐ and interday accuracy levels were within ±9.7%, whereas the intraday and interday precision levels were <11.3%. The extraction recovery, stability and matrix effect were within acceptable limits. The validated method was successfully applied for the pharmacokinetic analysis of R,S‐goitrin in rats after oral administration. Moreover, a total of six metabolites were structurally identified through UHPLC–Q/TOF–MS. The proposed metabolic pathways of R,S‐goitrin in rats involve demethylation, acetylation, glutathionylation and oxygenation.     

Characterization of forsythoside A metabolites in rats by a combination of UHPLC‐LTQ‐Orbitrap mass spectrometer with multiple data processing techniques

Forsythoside A (FTA), the main active constituent isolated from Fructus Forsythiae, has various biological functions including anti‐oxidant, anti‐viral and anti‐microbial activities. However, while research on FTA has been mainly focused on the treatment of diseases on a material basis, FTA metabolites in vivo have not been comprehensively evaluated. Here, a rapid and sensitive method using a UHPLC‐LTQ‐Orbitrap mass spectrometer with multiple data processing techniques including high‐resolution extracted ion chromatograms, multiple mass defect filters and diagnostic product ions was developed for the screening and identification of FTA metabolites in rats. As the result, a total of 43 metabolites were identified in biological samples including 42 metabolites in urine, 22 metabolites in plasma and 15 metabolites in feces. These results demonstrated that FTA underwent a series of in vivo metabolic reactions including methylation, dimethylation, sulfation, glucuronidation, diglucuronidation, cysteine conjugation and their composite reactions. The research enhanced our understanding of FTA metabolism and built a foundation for further toxicity and safety studies.     

Rapid analysis of Saposhnikovia divaricate decoction metabolism in rats by UHPLC–Q-TOFMS and multivariate statistical analysis

Saposhnikovia divaricata is a commonly used traditional Chinese medicine in treating various diseases such as pyrexia, rheumatism and headache. So far, there have been few reports on the metabolism of orally administered Saposhnikovia divaricate decoction (SDD), hindering further study on its bioactive components and their pharmacological characteristics. In the present study, ultra-performance liquid chromatography–quadrupole time-of-flight mass spectrometry (UHPLC–Q-TOFMS) was used coupled with principal component analysis (PCA) and partial least squared discriminant analysis (PLS-DA) to rapidly discover and identify the metabolites of SDD. According to the result of PLS-DA, a total of 139 ions of interest including 87 positive ions and 52 negative ions were extracted as SDD-related xenobiotics in urine. Finally, 12 and 65 compounds were identified as absorbed parent components and metabolites of SDD, respectively. Among them, 40 new metabolites were reported for the first time. Our results suggested that hydrolysis, hydroxylation, glucuronidation and sulfation are the major metabolic pathways of chromones, while hydroxylation, hydrogenation and sulfation are the main metabolic pathways of coumarins. This study is the first to explore the absorption and metabolism of SDD using UHPLC–Q-TOFMS, with results providing a basis for further study of its pharmacokinetics and discovery of its bioactive components.     

Identification of the absorptive constituents and their metabolites in vivo of Puerariae Lobatae Radix decoction orally administered in WZS‐miniature pigs by HPLC‐ESI‐Q‐TOFMS

In this study, the technique of high‐performance liquid chromatography coupled with electrospray ionization quadrupole time‐of‐flight mass spectrometry (HPLC‐ESI‐Q‐TOFMS) was used to analyze and identify the absorptive constituents and their metabolites in drug‐containing urine of Wuzhishan (WZS)‐miniature pigs administered with Puerariae Lobatae Radix (PLR) decoction. With the accurate mass measurements (<5 ppm) and effective MS² fragment ions, 96 compounds, including eight original constituents and 88 metabolites, were identified from the drug‐containing urine. Among these, 64 metabolites were new ones and their structures can be categorized into five types: isoflavones, puerols, O‐desmethylangolensins, equols and isoflavanones. In particular, puerol‐type constituents in PLR were first proved to be absorptive in vivo. Meanwhile, the metabolic pathways of PLR in vivo were investigated. On the basis of relative content of the identified compounds, 13 major metabolites accounting for approximately 50% of the contents, as well as their corresponding 12 prototype compounds, were determined as the major original absorptive constituents and metabolites of PLR in vivo. The HPLC‐ESI‐Q‐TOFMS technique proved to be powerful for characterizing the chemical constituents from the complicated traditional Chinese medicine matrices in this research. Copyright © 2013 John Wiley & Sons, Ltd.     

Metabolomics analysis of the therapeutic mechanism of Semen Descurainiae Oil on hyperlipidemia rats using 1H‐NMR and LC–MS

Semen descurainiae oil (SDO) is an important traditional Chinese medicine that was recently discovered to have the function of reducing blood lipids. Metabolomics analyses of plasma, liver and kidney in rats were performed using ¹H‐NMR and LC–MS to illuminate the lower blood lipid concentration effect of SDO, and niacin was considered as the active control. The measure of total cholesterol (TC) and low‐density‐lipoprotein cholesterol (LDL‐C) in plasma showed that SDO treatment decreased significantly the content of TC and LDL‐C. An orthogonal partial least squares–discriminant analysis approach was applied to identify the different metabolic profiles of plasma, liver and kidney in rats and to detect related potential biomarkers. The results suggested that the metabolic profiles of the control group and hyperlipidemia group showed significant difference and the SDO and niacin group had effective anti‐hyperlipidemia function. The biomarkers primarily concern lipid metabolism, amino acid metabolism and glycometabolism, and the change in biomarkers indicated that hyperlipidemia could cause the unbalance of these metabolic pathways in vivo. SDO reduced blood lipids by repairing amino acid and lipid metabolism.     

Study of tamoxifen urinary metabolites in rat by ultra‐high‐performance liquid chromatography time‐of‐flight mass spectrometry

Tamoxifen (TMX) is a nonsteroidal estrogen antagonist drug used for the treatment of breast cancer. It is also included in the list of banned substances of the World Anti Doping Agency (WADA) prohibited in and out of competition. In this work, the excretion of urinary metabolites of TMX after a single therapeutic dose administration in rats has been studied using ultra‐high‐performance liquid chromatography electrospray time‐of‐flight mass spectrometry (UHPLC‐TOFMS). A systematic strategy based on the search of typical biotransformations that a xenobiotic can undergo in living organisms, based on their corresponding molecular formula modification and accurate mass shifts, was applied for the identification of TMX metabolites. Prior to UHPLC‐TOFMS analyses, a solid‐phase extraction step with polymeric cartridges was applied to urine samples. Up to 38 TMX metabolites were detected. Additional collision induced dissociation (CID) MS/MS fragmentation was performed using UHPLC‐QTOFMS. Compared with recent previous studies in human urine and plasma, new metabolites have been reported for the first time in urine. Metabolites identified in rat urine include the oxygen addition, owing to different possibilities for the hydroxylation of the rings in different positions (m/z 388.2271), the incorporation of two oxygen atoms (m/z 404.2220) (including dihydroxylated derivatives or alternatives such as epoxidation plus hydroxylation or N‐oxidation and hydroxylation), epoxide formation or hydroxylation and dehydrogenation [m/z 386.2114 (+O –H₂)], hydroxylation of the ring accompanied by N‐desmethylation (m/z 374.2115), combined hydroxylation and methoxylation (m/z 418.2377), desaturated TMX derivate (m/z 370.2165) and its N‐desmethylated derivate (m/z 356.2009), the two latter modifications not previously being reported in urine. These findings confirm the usefulness of the proposed approach based on UHPLC‐TOFMS. Copyright © 2015 John Wiley & Sons, Ltd.     

Multi‐analysis strategy for metabolism of Andrographis paniculata in rat using liquid chromatography/quadrupole time‐of‐flight mass spectrometry

Compared with chemical drugs, it is a huge challenge to identify active ingredients of multicomponent traditional Chinese medicine (TCM). For most TCMs, metabolism investigation of absorbed constituents is a feasible way to clarify the active material basis. Although Andrographis paniculata (AP) has been extensively researched by domestic and foreign scholars, its metabolism has seldom been fully addressed to date. In this paper, high‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry was applied to analysis and characterization of AP metabolism in rat urine and feces samples after oral administration of ethanol extract. The differences in metabolites and metabolic pathways between the two biological samples were further compared. The chemical structures of 20 components were tentatively identified from drug‐treated biological samples, including six prototype components and 14 metabolites, which underwent such main metabolic pathways as hydrolyzation, hydrogenation, dehydroxylation, deoxygenation, methylation, glucuronidation, sulfonation and sulfation. Two co‐existing components were found in urine and feces samples, suggesting that some ingredients' metabolic processes were not unique. This study provides a comprehensive report on the metabolism of AP in rats, which will be helpful for understanding its mechanism. Copyright © 2014 John Wiley & Sons, Ltd.     

Metabonomic analysis of the anti‐inflammatory effects of volatile oils of Angelica sinensis on rat model of acute inflammation

Metabonomics based on GC‐MS was used to study the possible anti‐inflammatory mechanisms of volatile oils of Angelica sinensis (VOAS) in rats with acute inflammation. Acute inflammation was induced by subcutaneous injection of carrageenan in rats. The levels of prostaglandin E₂ (PGE₂), histamine (HIS) and 5‐hydroxytryptamine (5‐HT) in the inflammatory fluid were detected. Principal component analysis and orthogonal partial least squares‐discriminant analysis models were performed for pattern recognition analysis. After the administration of VOAS, the levels of PGE₂, HIS, and 5‐HT returned to levels observed in normal group. According to GC‐MS analysis, the intervention of VOAS in rats with acute inflammation induced substantial and characteristic changes in their metabolic profiles. Fourteen metabolite biomarkers, namely, lactic acid, malic acid, citric acid, trans‐dehydroandrosterone, aldosterone, linoleic acid, hexadecanoic acid, pregnenolone, octadecenoic acid, myristic acid, l ‐histidine, octadecanoic acid, arachidonic acid (AA) and l ‐tryptophan, were detected in the inflammatory fluid. The levels of all biomarkers either increased or decreased significantly in model groups. VOAS possibly intervened in the metabolic process of inflammation by altering histidine metabolism, tryptophan metabolism, AA metabolism, steroid hormone biosynthesis, fatty acid metabolism and energy metabolism. Metabonomics was used to reflect an organism's physiological and metabolic state comprehensively, and it is a potentially powerful tool that reveals the anti‐acute‐inflammatory mechanism of VOAS. Copyright © 2014 John Wiley & Sons, Ltd.