Zhanpeng Shang

Profiling and identification of (-)-epicatechin metabolites in rats using ultra-high performance liquid chromatography coupled with linear trap-Orbitrap mass spectrometer.

(-)-Epicatechin (EC), an optical antipode of (+)-catechin (C), possesses many potential significant health benefits. However, the in vivo metabolic pathway of EC has not been clarified yet. In this study, an efficient strategy based on ultra-high performance liquid chromatography coupled with a linear ion trap-Orbitrap mass spectrometer was developed to profile and characterize EC metabolites in rat urine, faeces, plasma, and various tissues. Meanwhile, post-acquisition data-mining methods including high-resolution extracted ion chromatogram (HREIC), multiple mass defect filters (MMDFs), and diagnostic product ions (DPIs) were utilized to screen and identify EC metabolites from HR-ESI-MS1 to ESI-MSn stage. Finally, a total of 67 metabolites (including parent drug) were tentatively identified based on standard substances, chromatographic retention times, accurate mass measurement, and relevant drug biotransformation knowledge. The results demonstrated that EC underwent multiple in vivo metabolic reactions including methylation, dehydration, hydrogenation, glucosylation, sulfonation, glucuronidation, ring-cleavage, and their composite reactions. Among them, methylation, dehydration, glucosylation, and their composite reactions were observed only occurring on EC when compared with C. Meanwhile, the distribution of these detected metabolites in various tissues including heart, liver, spleen, lung, kidney, and brain were respectively studied. The results demonstrated that liver and kidney were the most important organs for EC and its metabolites elimination. In conclusion, the newly discovered EC metabolites significantly expanded the understanding on its pharmacological effects and built the foundation for further toxicity and safety studies. Copyright

Identification of Metabolites of 6'-Hydroxy-3,4,5,2',4'-pentamethoxychalcone in Rats by a Combination of Ultra-High-Performance Liquid Chromatography with Linear Ion Trap-Orbitrap Mass Spectrometry Based on Multiple Data Processing Techniques.

In this study, an efficient strategy was established using ultra-high-performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap MS) to profile the in vivo metabolic fate of 6′-hydroxy-3,4,5,2′,4′-pentamethoxychalcone (PTC) in rat urine and feces. The UHPLC-LTQ-Orbitrap method combines the high trapping capacity and MSn scanning function of the linear ion trap along with accurate mass measurements within 5 ppm and a resolving power of up to 30,000 over a wider dynamic range compared to many other mass spectrometers. In order to reduce the potential interferences of endogenous substances, the post-acquisition processing method including high-resolution extracted ion chromatogram (HREIC) and multiple mass defect filters (MMDF) were developed for metabolite detection. As a result, a total of 60 and 35 metabolites were detected in the urine and feces, respectively. The corresponding in vivo reactions such as methylation, hydroxylation, hydrogenation, decarbonylation, demethylation, dehydration, methylation, demethoxylation, sulfate conjugation, glucuronide conjugation, and their composite reactions were all detected in this study. The result on PTC metabolites significantly expanded the understanding of its pharmacological effects, and could be targets for future studies on the important chemical constituents from herbal medicines.

An integrated strategy for rapid discovery and identification of the sequential piperine metabolites in rats using ultra high-performance liquid chromatography/high resolution mass spectrometery

HIGHLIGHTSAn integrated approach based on ultra high‐performance liquid chromatography/high resolution mass spectrometry coupled with various data‐mining methods was developed for metabolite profiling of piperine.Reverse molecular assembly strategy based on paired diagnostic product ions and neutral loss fragments was constructed to achieve rapid structural elucidation.A total of 148 metabolites as well as parent compound were positively or tentatively identified. ABSTRACT Piperine, one of the major bioactive constituents isolated from natural flavorings and medicinal‐culinary herbs, possesses various biological activities. In the present study, an integrated strategy based on ultra high‐performance liquid chromatography/high resolution mass spectrometry was established to reveal piperine metabolism in rats. First of all, post‐acquisition data‐mining methods, including high resolution extracted ion chromatograms (HREICs) and multiple mass defect filtering (MMDF), were used to screen piperine metabolite candidates in a full‐scan HRMS1 level. Then, parent ion list‐dynamic exclusion coupled with data‐dependent data‐acquisition method was utilized to acquire MSn datasets. In addition, the established reverse molecular assembly (RMA) approach based on paired diagnostic product ions (pDPIs) coupled with neutral loss fragments (NLFs) was used to ascertain and identify the major‐to‐trace piperine metabolites efficiently. And then, the calculated ClogP values were utilized to distinguish the positional isomers. As a result, a total of 148 piperine metabolites were detected and characterized tentatively. The results demonstrated that piperine mainly underwent hydrogenation, dehydrogenation, hydroxylation, glucuronide conjugation, sulfate conjugation, ring‐cleavage, and their composite reactions. Our results not only provided novel and useful data to better understand the safety, toxicity and efficacy of this potential therapeutic agent, but also indicated that the proposed strategy was reliable for a rapid discovery and identification drug‐related constituents in vivo.

Rapid profiling and identification of puerarin metabolites in rat urine and plasma after oral administration by UHPLC-LTQ-Orbitrap mass spectrometer

Puerarin, a bioactive natural C-glycoside isoflavonoid isolated from Pueraria lobata (Willd.) Ohwi, possesses many potential health benefits. However, the in vivo metabolic fates of puerarin have not been comprehensively clarified yet. In this study, an efficient strategy based on UHPLC-LTQ-Orbitrap mass spectrometer in both positive and negative ion modes was developed to profile and characterize puerarin metabolites in rat urine and plasma. Meanwhile, post-acquisition data-mining methods including high-resolution extracted ion chromatogram (HREIC) and multiple mass defect filtering (MMDF) were utilized to screen potential puerarin metabolites from HR-ESI-MS1 stage. The mass fragmentation behaviors of five reference standards, including puerarin, daidzin, daidzein, genistin, and genistein, were comprehensively studied for construction of diagnostic product ions (DPIs), which could be employed to implement rapid identification of puerarin metabolites. Finally, a total of 66 metabolites (prototype compound included) were tentatively or positively identified based on standard substances, chromatographic retention times, accurate mass measurement, and corresponding ClogP values. Our results demonstrated that puerarin underwent multiple in vivo metabolic reactions including methylation, hydroxylation, dehydroxylation, hydrogenation, deglycosylation, glycosylation, sulfonation, glucuronidation, and their complicated reactions. In conclusion, the newly discovered puerarin metabolites significantly expanded the understanding on its pharmacological effects and built the foundation for further toxicity and safety studies.

UHPLC-LTQ-Orbitrap-based metabolomics coupled with metabolomics pathway analysis method for exploring the protection mechanism of Kudiezi injection in a rat anti-ischemic cerebral reperfusion damage model

Kudiezi injection has been used extensively in the treatment of cerebrovascular and cardiovascular diseases. However, its therapeutic effects and underlying mechanism of action are not fully understood. The aim of the present study was to clarify the protective mechanisms of Kudiezi injection on cerebral ischemic injury, using metabolomics methods. Middle cerebral artery occlusion (MCAO) was introduced in rats to build the cerebral ischemic damage. UHPLC-LTQ-Orbitrap-based analytical method was established for analysis of the metabolites. The raw mass data of all samples were normalized with Sieve 2.2 software and then introduced to orthogonal partial least squares discriminant analysis (OPLS-DA) model. Finally, 23 metabolites in plasma (15 were tentatively identified) were chosen as potential biomarkers, according to accurate mass measurements (< 5 ppm), MS/MS fragmentation patterns, and diagnostic product ions. Furthermore, on the basis of metabolic pathway analysis via metabolomics pathway analysis (MetPA), we first discovered that the protection mechanism in anti-ischemic cerebral reperfusion damage of Kudiezi injection was possibly related to the biosynthesis of phenylalanine, tyrosine, and tryptophan. The present study provided a useful approach for exploring the mechanism of ischemic stroke and evaluating the efficacy of Kudiezi injection or other traditional medicines.

Profiling and identification of chlorogenic acid metabolites in rats by ultra-high-performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometer

Abstract 1. Chlorogenic acids (CGAs), one kind of major bioactive constituents isolated from Flos Lonicera Japonica, possess many biological activities, such as antibacterial, antioxidant and antiviral activities. In this study, we established an efficient strategy using ultra-high-performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap MS) to profile the in vivo metabolic fate of CGAs in rat urine and plasma. 2. The extract from Flos Lonicera Japonica was orally administrated to Sprague-Dawley (SD) rats at a dose of 1000 mg/kg body weight. Then, a combination of various post-acquisition data mining methods, including high-resolution extracted ion chromatogram (HREIC) and multiple mass defect filters (MMDFs) and diagnostic product ions (DPIs), were adopted to characterize the known and unknown CGA metabolites in SD rats. 3. As a result, a total of 68 CGA metabolites were unambiguously or tentatively screened and characterized. These metabolites, including 18 prototype compounds and 50 metabolites, were deduced to be yielded via methylation, hydrogenation, demethylation, dehydration, sulfate conjugation, glucuronide conjugation, glycosylation conjugation and their composite reactions, which mainly occurred to caffeoylquinic acids, dicaffeoylquinic acids, p-coumaroylquinic acids and feruloylquinic acids. 4. In conclusion, this study profiled CGA metabolites, which are useful in understanding the in vivo metabolic fate, effective forms, and pharmacological and toxic actions of CGAs.

Novelty application of multi-omics correlation in the discrimination of sulfur-fumigation and non-sulfur-fumigation Ophiopogonis Radix

A rapid and sensitive approach to differentiate sulfur-fumigated (SF) Ophiopogonis Radix based on Multi-Omics Correlation Analysis (MOCA) strategy was first established. It was characterized by multiple data-acquisition methods (NIR, HPLC, and UHPLC-HRMS) based metabonomics and multivariate statistical analysis methods. As a result, SF and non-sulfur fumigated (NSF) Ophiopogonis Radix samples were efficaciously discriminated. Moreover, based on the acquired HRMS data, 38 sulfur-containing discriminatory markers were eventually characterized, whose NIR absorption could be in close correlation with the discriminatory NIR wavebands (5000–5200 cm−1) screened by NIR metabonomics coupled with SiPLS and 2D-COS methods. This results were also validated from multiple perspectives, including metabonomics analysis based on the discriminatory markers and the simulation of SF ophiopogonin D and Ophiopogonis Radix sample. In conclusion, our results first revealed the intrinsic mechanism of discriminatory NIR wavebands by means of UHPLC-HRMS analysis. Meanwhile, the established MOCA strategy also provided a promising NIR based differential method for SF Ophiopogonis Radix, which could be exemplary for future researches on rapid discrimination of other SF Chinese herbal medicines.

Analysis of Non-Volatile Chemical Constituents of Menthae Haplocalycis Herba by Ultra-High Performance Liquid Chromatography-High Resolution Mass Spectrometry

Menthae Haplocalycis herba, one kind of Chinese edible herbs, has been widely utilized for the clinical use in China for thousands of years. Over the last decades, studies on chemical constituents of Menthae Haplocalycis herba have been widely performed. However, less attention has been paid to non-volatile components which are also responsible for its medical efficacy than the volatile constituents. Therefore, a rapid and sensitive method was developed for the comprehensive identification of the non-volatile constituents in Menthae Haplocalycis herba using ultra-high performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap). Separation was performed with Acquity UPLC® BEH C18 column (2.1 mm × 100 mm, 1.7 μm) with 0.2% formic acid aqueous solution and acetonitrile as the mobile phase under gradient conditions. Based on the accurate mass measurement (<5 ppm), MS/MS fragmentation patterns and different chromatographic behaviors, a total of 64 compounds were unambiguously or tentatively characterized, including 30 flavonoids, 20 phenolic acids, 12 terpenoids and two phenylpropanoids. Finally, target isolation of three compounds named Acacetin, Rosmarinic acid and Clemastanin A (first isolated from Menthae Haplocalycis herba) were performed based on the obtained results, which further confirmed the deduction of fragmentation patterns and identified the compounds profile in Menthae Haplocalycis herba. Our research firstly systematically elucidated the non-volatile components of Menthae Haplocalycis herba, which laid the foundation for further pharmacological and metabolic studies. Meanwhile, our established method was useful and efficient to screen and identify targeted constituents from traditional Chinese medicine extracts.

Rapid Screening and Identification of Daidzein Metabolites in Rats Based on UHPLC-LTQ-Orbitrap Mass Spectrometry Coupled with Data-Mining Technologies

Daidzein, the main bioactive soy isoflavone in Nature, has been found to possess many biological functions. It has been investigated in particular as a phytoestrogen owing to the similarity of its structure with that of the human hormone estrogen. Due to the lack of comprehensive studies on daidzein metabolism, further research is still required to clarify its in vivo metabolic fate and intermediate processes. In this study, an efficient strategy was established using UHPLC-LTQ-Orbitrap mass spectrometry to profile the metabolism of daidzein in rats. Meanwhile, multiple data-mining methods including high-resolution extracted ion chromatogram (HREIC), multiple mass defect filtering (MMDF), neutral loss fragment (NLF), and diagnostic product ion (DPI) were utilized to investigate daidzein metabolites from the HR-ESI-MS1 to ESI-MSn stage in both positive and negative ion modes. Consequently, 59 metabolites, including prototype compounds, were positively or tentatively elucidated based on reference standards, accurate mass measurements, mass fragmentation behaviors, chromatographic retention times, and corresponding calculated ClogP values. As a result, dehydration, hydrogenation, methylation, dimethylation, glucuronidation, glucosylation, sulfonation, ring-cleavage, and their composite reactions were ascertained to interpret its in vivo biotransformation. Overall, our results not only revealed the potential pharmacodynamics forms of daidzein, but also aid in establishing a practical strategy for rapid screening and identifying metabolites of natural compounds.

Multiple perspectives of qingkailing injection-fraction-single compound in revealing the hepatotoxicity of baicalin and hyodeoxycholic acid

ETHNOPHARMACOLOGICAL RELEVANCE The complexity of ingredients in traditional Chinese medical formulas and the limited consideration of toxicological responses are fundamental issues that hamper prognostic information of drug quality control. MATERIALS AND METHODS A multidisciplinary approach for quality control of Qingkailing injection (QKL) regarding drug induced liver toxicity was described for the first time. High content image analysis (HCA) was combined with reverse-phase chromatographic separation and high-resolution MS detection technologies to provide the dynamic responses of drug induced HepG2 cell injury. Firstly, a simple and rapid method for simultaneous qualification and quantification of 21 major constituents in QKL was established and validated using ultra-high performance liquid chromatography-hybrid quadrupole-Orbitrap mass spectrometer (UHPLC-Q-Orbitrap), which were operated in full MS/dd-MS2 mode and thus simultaneously acquired quantitative high resolution (HR) full scan data and confirmatory HR MS2 data. Secondly, repeated semi-preparation HPLC was applied to obtain four fractions (F1-F4) for HCS analysis. Finally, potential hepatotoxicity was determined by five hepatotoxicity biomarkers, including cell loss, DNA condense, glutathione (GSH) depletion, reactive oxygen species (ROS) formation, and mitochondria membrane potential (MMP) depolarization. RESULTS The detection in polarity switching mode empowered the coverage of comprehensive constituents with different chemical properties. Satisfactory linearity precisions, repeatability, stability, and recovery were achieved. QKL injection significantly induced HepG2 cell injury above the concentration of 1.25% (v/v). Meanwhile, flavone glycosides (F3) and stinasterols (F4) fractions exhibited hepatotoxicity above 75μg/mL and 50μg/mL, respectively. Still further, baicalin originated from F3 significantly caused cell loss and glutathione (GSH) depletion. In parallel, hyodeoxycholic acid from F4 induced cell loss, nucleus condense, and GSH reduction as well. CONCLUSIONS Our work provides multiple perspectives based on injection-fractions-single compound format to improve QKL pharmacovigilance through revealing the potential hepatotoxic material basis. Additionally, our study provides an integrating paradigm for the comprehensive and systematic quality control of traditional Chinese medical formulas.