A Comprehensive Screening and Identification of Genistin Metabolites in Rats Based on Multiple Metabolite Templates Combined with UHPLC-HRMS Analysis

A UPLC-MS/MS Based Rapid, Sensitive, and Non-Enzymatic Methodology for Quantitation of Dietary Isoflavones in Biological Fluids

Dietary isoflavones, a type of phytoestrogens, have gained importance owing to their health-promoting benefits. However, the beneficial effects of isoflavones are mediated by smaller metabolites produced with the help of gut bacteria that are known to metabolize these phytoestrogenic compounds into Daidzein and Genistein and biologically active molecules such as S-Equol. Identifying and measuring these phytoestrogens and their metabolites is an important step towards understanding the significance of diet and gut microbiota in human health and diseases. We have overcome the reported difficulties in quantitation of these isoflavones and developed a simplified, sensitive, non-enzymatic, and sulfatases-free extraction methodology. We have subsequently used this method to quantify these metabolites in the urine of mice using UPLC-MS/MS. The extraction and quantitation method was validated for precision, linearity, accuracy, recoveries, limit of detection (LOD), and limit of quantification (LOQ). Linear calibration curves for Daidzein, Genistein, and S-Equol were set up by performing linear regression analysis and checked using the correlation coefficient (r2 > 0.995). LOQs for Daidzein, Genistein, and S-Equol were 2, 4, and 2 ng/mL, respectively. This UPLC-MS/MS swift method is suitable for quantifying isoflavones and the microbial-derived metabolite S-Equol in mice urine and is particularly useful for large numbers of samples.

Microbial-Transferred Metabolites of Black Tea Theaflavins by Human Gut Microbiota and Their Impact on Antioxidant Capacity

Theaflavins (TFs), the primary bioactive components in black tea, are poorly absorbed in the small intestine. However, the biological activity of TFs does not match their low bioavailability, which suggests that the gut microbiota plays a crucial role in their biotransformation and activities. In this study, we aimed to investigate the biotransferred metabolites of TFs produced by the human gut microbiota and these metabolites' function. We profiled the microbial metabolites of TFs by in vitro anaerobic human gut microbiota fermentation using liquid chromatography tandem mass spectrometry (LC-MS/MS) methods. A total of 17 microbial metabolites were identified, and their corresponding metabolic pathways were proposed. Moreover, full-length 16S rRNA gene sequence analysis revealed that the TFs altered the gut microbiota diversity and increased the relative abundance of specific members of the microbiota involved in the catabolism of the TFs, including Flavonifractor_plautii, Bacteroides_uniformis, Eubacterium_ramulus, etc. Notably, the antioxidant capacity of the TF sample increased after fermentation compared to the initial sample. In conclusion, the results contribute to a more comprehensive understanding of the microbial metabolites and antioxidant capacity of TFs.

Tanshinone-I for the treatment of uterine fibroids: Molecular docking, simulation, and density functional theory investigations

Uterine fibroids (UF), most prevalent gynecological disorder, require surgery when symptomatic. It is estimated that between 25 and 35 percent of women wait until the symptoms have worsened like extended heavy menstrual bleeding and severe pelvic pain. These UF may be reduced in size through various methods such as medical or surgical intervention. Progesterone (prog) is a crucial hormone that restores the endometrium and controls uterine function. In the current study, 28 plant-based molecules are identified from previous literature and docked onto the prog receptors with 1E3K and 2OVH. Tanshinone-I has shown the best docking score against both proteins. The synthetic prog inhibitor Norethindrone Acetate is used as a standard to evaluate the docking outcomes. The best compound, tanshinone-I, was analyzed using molecular modeling and DFT. The RMSD for the 1E3K protein-ligand complex ranged from 0.10 to 0.42 Å, with an average of 0.21 Å and a standard deviation (SD) of 0.06, while the RMSD for the 2OVH protein-ligand complex ranged from 0.08 to 0.42 Å, with an average of 0.20 Å and a SD of 0.06 showing stable interaction. In principal component analysis, the observed eigen values of HPR-Tanshinone-I fluctuate between -1.11 to 1.48 and -1.07 to 1.25 for PC1 and PC2, respectively (1E3K), and the prog-tanshinone-I complex shows eigen values of -38.88 to -31.32 and -31.32 to 35.87 for PC1 and PC2, respectively (2OVH), which shows Tanshinone-I forms a stable protein-ligand complex with 1E3K in comparison to 2OVH. The Free Energy Landscape (FEL) analysis shows the Gibbs free energy in the range of 0 to 8 kJ/mol for Tanshinone-I with 1E3K and 0 to 14 kJ/mol for Tanshinone-I with the 2OVH complex. The DFT calculation reveals ΔE value of 2.8070 eV shows tanshinone-I as a stable compound. 1E3K modulates the prog pathway, it may have either an agonistic or antagonistic effect on hPRs. Tanshinone-I can cause ROS, apoptosis, autophagy (p62 accumulation), up-regulation of inositol requiring protein-1, enhancer-binding protein homologous protein, p-c-Jun N-terminal kinase (p-JNK), and suppression of MMPs. Bcl-2 expression can change LC3I to LC3II and cause apoptosis through Beclin-1 expression.

The Metabolites and Mechanism Analysis of Genistin against Hyperlipidemia via the UHPLC-Q-Exactive Orbitrap Mass Spectrometer and Metabolomics

Genistin, an isoflavone, has been reported to have multiple activities. However, its improvement of hyperlipidemia is still unclear, and the same is true with regard to its mechanism. In this study, a high-fat diet (HFD) was used to induce a hyperlipidemic rat model. The metabolites of genistin in normal and hyperlipidemic rats were first identified to cause metabolic differences with Ultra-High-Performance Liquid Chromatography Quadrupole Exactive Orbitrap Mass Spectrometry (UHPLC-Q-Exactive Orbitrap MS). The relevant factors were determined via ELISA, and the pathological changes of liver tissue were examined via H&E staining and Oil red O staining, which evaluated the functions of genistin. The related mechanism was elucidated through metabolomics and Spearman correlation analysis. The results showed that 13 metabolites of genistin were identified in plasma from normal and hyperlipidemic rats. Of those metabolites, seven were found in normal rat, and three existed in two models, with those metabolites being involved in the reactions of decarbonylation, arabinosylation, hydroxylation, and methylation. Three metabolites, including the product of dehydroxymethylation, decarbonylation, and carbonyl hydrogenation, were identified in hyperlipidemic rats for the first time. Accordingly, the pharmacodynamic results first revealed that genistin could significantly reduce the level of lipid factors (p < 0.05), inhibited lipid accumulation in the liver, and reversed the liver function abnormalities caused by lipid peroxidation. For metabolomics results, HFD could significantly alter the levels of 15 endogenous metabolites, and genistin could reverse them. Creatine might be a beneficial biomarker for the activity of genistin against hyperlipidemia, as revealed via multivariate correlation analysis. These results, which have not been reported in the previous literature, may provide the foundation for genistin as a new lipid-lowering agent.

Understanding the Phytoestrogen Genistein Actions on Breast Cancer: Insights on Estrogen Receptor Equivalence, Pleiotropic Essence and Emerging Paradigms in Bioavailability Modulation

Prevalent as a major phenolic ingredient of soy and soy products, genistein is recognized as an eminent phytoestrogen owing to its interacting ability with estrogen receptors (ERs). The metabolic conversion of plant-derived genistin to genistein by gut microbes and intestinal enzymes enhances its absorption at intestinal pH of ~7.5-7.8. Genistein interferes in breast cancer (BC) development via pleiotropic actions on cell proliferation, survival, angiogenesis, and apoptosis. Though multiple investigations have demonstrated genistein intake-driven reduced BC risk, similar efficacy has not been replicated in clinical trials. Furthermore, multiple studies have structurally and functionally equated genistein extents with 17-β-estradiol (E2), the most available physiological estrogen in females, culminating in aggravated BC growth. Of note, both genistein and E2 function via interacting with ERs (ERα and ERβ). However, although E2 shows almost equal affinity towards both ERα and ERβ, genistein shows more affinity towards ERβ than ERα. Our cautious literature survey revealed typical intake mode, ER expression pattern and the ratio of ERα and ERβ, transactivators/ regulators of ERα and ERβ expression and activities, patient age, and menopausal status as decisive factors affecting genistein BC activities. Of further interest are the mechanisms by which genistein inhibits triple-negative breast cancers (TNBCs), which lack ERs, progesterone receptors (PRs), and human epidermal growth factor receptors (HER2). Herein, we attempt to understand the dosage-specific genistein actions in BC cells and patients with an insight into its better response via derivative development, nanocarrier-assisted, and combinatorial delivery with chemotherapeutic drugs.

Elucidation of active ingredients and mechanism of action of hawthorn in the prevention and treatment of atherosclerosis

Hawthorn (HT), a functional food and medicinal herb for centuries in China, has potential preventive and therapeutic effects on atherosclerosis (AS). However, the mechanisms and active ingredients of HT in the prevention and treatment of AS are unclear. This study aimed to reveal active components and mechanism of HT in the prevention and treatment of AS using UHPLC-Q-Exactive Orbitrap MS and network pharmacology. A total of 50 compounds were identified by UHPLC-Q-Exactive Orbitrap MS. Six core targets and six active compounds were obtained by network pharmacology. Apigenin, luteolin, chrysin, quercetin, oleanic acid, and corosolic acid were the active components in the prevention and treatment of AS, and core targets included SRC, HSP90AA1, MAPK3, EGFR, HRAS, and AKT1. The key signaling pathways involved are MAPK, HIF-1, NF-kappa B, PI3K-Akt, TNF, Rap1, Ras, and VEGF signaling pathways. Further molecular docking results indicated that the six active compounds had strong hydrogen bonding ability with the six core targets. On the molecular level, HT may regulate AS by controlling cell survival and proliferation, reducing the levels of enzymes HMG-CoA reductase and lipoprotein lipase and inhibiting inflammatory response. PRACTICAL APPLICATIONS: HT can serve as "medicine-food homology" for dietary supplement and exert potential preventive and therapeutic effects on AS. However, the mechanisms of HT in the prevention and treatment of AS are unclear. This study describes a rapid method of detecting and identifying the components and mechanism of HT based on LC-MS and network pharmacology, which provides a theoretical and scientific support for further application of HT and guidance for the research of other herbal medicines.

Metabolite Identification of HIV-1 Capsid Modulators PF74 and 11L in Human Liver Microsomes

PF74 and 11L, as potent modulators of the HIV-1 capsid protein, have been demonstrated to act at both early and late stages in the HIV-1 life cycle. However, their clearance is high in human liver microsomes (HLMs). The main goal of this study was to clarify the metabolism of PF74 and 11L in HLMs, and provide guidance for future structural optimization. To accomplish this, the phase-I metabolites of PF74 and 11L, resulting from in vitro incubation with HLMs, were investigated via ultra-performance liquid chromatography–ultraviolet–high-resolution mass spectrometry (UPLC–UV–HRMS). The results show that 17 phase-I metabolites were putatively annotated for PF74, whereas 16 phase-I metabolites were found for 11L. The main metabolic pathways of PF74 in HLMs were oxidation and demethylation, and the secondary metabolic pathway was hydrolysis; thus, the di-oxidation and demethylation products (M7, M9, M11, and M14) were found to be major metabolites of PF74 in HLMs. In comparison, the main metabolic pathways of 11L in HLMs were oxidation, demethylation, dehydrogenation, and oxidative deamination, with M6′, M11′, M15′, and M16′ as the main metabolites. We suggest that the indole ring and N-methyl group of PF74, and the aniline group, benzene ring R1′, N-methyl, and methoxy group of 11L, were the main metabolic soft spots. Therefore, our research illuminates structural optimization options in seeking improved HIV-1 CA modulators.

Extensive metabolism of flavonoids relevant to their potential efficacy on Alzheimer's disease

Alzheimer's disease (AD) is an age-related neurodegenerative disorder, the incidence of which is climbing with ever-growing aged population, but no cure is hitherto available. The epidemiological studies unveiled that chronic intake of flavonoids was negatively associated with AD risk. Flavonoids, a family of natural polyphenols widely distributed in human daily diets, were readily conjugated by phase II drug metabolizing enzymes after absorption in vivo, and glucuronidation could occur in 1 min following intravenous administration. Recently, as many as 191 metabolites were obtained after intragastric administration of a single flavonoid, indicating that other bioactive metabolites, besides conjugates, might be formed and account for the contradiction between efficacy of flavonoids in human or animal models and low systematic exposure of flavonoid glycosides or aglycones. In this review, metabolism of complete 68 flavonoid monomers potential for AD treatment, grouped in flavonoid O-glycosides, flavonoid aglycones, flavonoid C-glycosides, flavonoid dimers, flavonolignans and prenylated flavonoids according to their common structural elements, respectively, has been systematically retrospected, summarized and discussed, including their unequivocally identified metabolites, metabolic interconversions, metabolic locations, metabolic sites (regio- or stereo-selectivity), primarily involved metabolic enzymes or intestinal bacteria, and interspecies correlations or differences in metabolism, and their bioactive metabolites and the underlying mechanism to reverse AD pathology were also reviewed, providing whole perspective about advances on extensive metabolism of diverse potent flavonoids in vivo and in vitro up to date and aiming at elucidation of mechanism of actions of flavonoids on AD or other central nervous system (CNS) disorders.

Comprehensive metabolism study of swertiamarin in rats using ultra high-performance liquid chromatography coupled with Quadrupole-Exactive Orbitrap mass spectrometry

Swertiamarin, a natural ingredient with potent pharmacological activities in the iridoid glycoside family, had been reported to have significant therapeutic effects on a variety of human diseases.In this study, a systematic and efficient strategy based on UHPLC-Q-Exactive Orbitrap mass spectrometry was established to reveal the metabolic profile of swertiamarin in rat urine, plasma, and faeces.First of all, post-acquisition data-mining methods, including multiple mass defect filters (MMDFs) and high-resolution extracted ion chromatograms (HREICs), were developed to screen the metabolite candidates of swertiamarin from the complete mass scan data sets.Second, according to the diagnostic product ions (DPIs), neutral loss fragments (NLFs), chromatographic retention time, accurate mass measurement and calculated Clog P values, all metabolite candidates were rapidly identified.As a consequence, 49 metabolites altogether, including archetype compound, were preliminarily characterised. The corresponding in vivo biotransformation processes, such as dehydration, dehydrogenation, hydroxylation, hydrogenation, methylation, sulphonation, N-acetylcysteine (NAC) formation, N-heterocyclisation and their composite reactions, were all discovered in the study.In conclusion, our results not only detailedly elucidated many new metabolites and metabolic pathways of swertiamarin, but also provided a reference for further study of its pharmacological mechanism and evaluation of its safety.

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.

Identification of Metabolites of Aurantio-Obtusin in Rats Using Ultra-High-Performance Liquid Chromatography-Q-Exactive Orbitrap Mass Spectrometry with Parallel Reaction Monitoring

Aurantio-obtusin (AO) is a major anthraquinone compound isolated from Cassiae Semen or Duhaldea nervosa, which possesses diverse pharmacological effects. Previous studies have shown that it has a good effect on lowering blood lipids and treating various diseases. A few studies have also reported about its metabolites. A rapid and reliable method using ultra-high-performance liquid chromatography-Q-Exactive Orbitrap mass spectrometry and multiple data-processing technologies was established to investigate the metabolites of AO in the plasma and various tissues of rats, including the heart, liver, spleen, lung, kidneys, and brain. Finally, a total of 36 metabolites were identified in the plasma of rats, which could be very beneficial for understanding the effective form of AO metabolites leading to new drug discovery. The result demonstrated that this strategy, especially parallel reaction monitoring, has shown a wide range of applications in the identification of metabolites.

A Rapid High Throughput Vibration and Vortex-Assisted Matrix Solid Phase Dispersion for Simultaneous Extraction of Four Isoflavones for Quality Evaluation of Semen Sojae Praeparatum

Isoflavones (daidzein, daidzin, genistein and genistin) were main chemical components and usually selected as markers for quality control of Traditional Chinese Medicine semen sojae praeparatum (SSP). High throughput vibration and vortex-assisted matrix solid phase dispersion and high performance liquid chromatography with diode array detection were developed to simultaneously extract and quantify four isoflavones in SSP. Some parameters influencing extraction efficiency of isoflavones by vortex-assisted matrix solid phase dispersion such as sorbent type, ratio of sample to sorbent, crushing time, vibration frequency, methanol concentration, eluting solvent volume and vortex time were optimized. It was found that the best extraction yields of four isoflavones were obtained when the sample (20 mg) and SBA-3 (40 mg) was crushed by ball mill machine for 2 min at vibration frequency of 800 times per minute. Methanol/water (1.5 ml, 8:2, v/v) solution was dropped into the treated sample and vortexed for 3 min. The recoveries of the four isoflavones ranged from 86.1 to 94.8% and all relative standard deviations were less than 5%. A good linearity (r > 0.9994) was achieved within the range 0.5-125 μg/ml. It was concluded that the high throughput vibration and vortex-assisted matrix solid-phase dispersion coupled with high performance liquid chromatography was user-friendly extraction and quantification method of multiple isoflavones for quality evaluation of SSP.

Comprehensive Screening and Identification of Phillyrin Metabolites in Rats Based on UHPLC-Q-Exactive Mass Spectrometry Combined with Multi-Channel Data Mining

Phillyrin, a well-known bisepoxylignan, has been shown to have many critical pharmacological activities. In this study, a novel strategy for the extensive acquisition and use of data was established based on UHPLC-Q-Exactive mass spectrometry to analyze and identify the in vivo metabolites of phillyrin and to elucidate the in vivo metabolic pathways of phillyrin. Among them, the generation of data sets was mainly due to multichannel data mining methods, such as high extracted ion chromatogram (HEIC), diagnostic product ion (DPI), and neutral loss filtering (NLF). A total of 60 metabolites (including the prototype compound) were identified in positive and negative ion modes based on intuitive and useful data such as the standard's cleavage rule, accurate molecular mass, and chromatographic retention time. The results showed that a series of biological reactions of phillyrin in vivo mainly included methylation, hydroxylation, hydrogenation, sulfonation, glucuronidation, demethylation, and dehydrogenation and their composite reactions. In summary, this study not only comprehensively explained the in vivo metabolism of phillyrin, but also proposed an effective strategy to quickly analyze and identify the metabolites of natural pharmaceutical ingredients in nature.

Enterohepatic Circulation and Pharmacokinetics of Genistin and Genistein in Rats

Genistin and its aglycone genistein of isoflavone are naturally occurring in plants. The aim of this study is to develop an experimental animal model of enterohepatic circulation to investigate the metabolic biotransformation of genistin and genistein in rats. A paired-rat model was developed in which the drug was administered intravenously to the donor rat whose bile duct was cannulated into the duodenum of the untreated recipient rat. The blood sample was collected from the jugular vein of the donor and recipient rats after genistin administration. The results demonstrate that genistein was detected in both the donor and recipient rats after genistein administration (50 mg/kg, iv) in the donor rat, which suggested that the enterohepatic circulation of genistein occurred. The same phenomenon happened again in the biotransformation after genistin administration (50 mg/kg, iv) in the donor rat. Genistein was detected in the recipient rat's blood sample after treatment with β-glucuronidase, which suggested that enzymatic hydrolysis occurred in the transformation of genistin into genistein. In conclusion, the research revealed the metabolic pathway of the glucuronidation of genistin into genistein.

A Complete Study of Farrerol Metabolites Produced in Vivo and in Vitro

Although farrerol, a characteristically bioactive constituent of Rhododendron dauricum L., exhibits extensive biological and pharmacological activities (e.g., anti-oxidant, anti-immunogenic, and anti-angiogenic) as well as a high drug development potential, its metabolism remains underexplored. Herein, we employed ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry coupled with multiple data post-processing techniques to rapidly identify farrerol metabolites produced in vivo (in rat blood, bile, urine and feces) and in vitro (in rat liver microsomes). As a result, 42 in vivo metabolites and 15 in vitro metabolites were detected, and farrerol shown to mainly undergo oxidation, reduction, (de)methylation, glucose conjugation, glucuronide conjugation, sulfate conjugation, N-acetylation and N-acetylcysteine conjugation. Thus, this work elaborates the metabolic pathways of farrerol and reveals the potential pharmacodynamics forms of farrerol.

Chemical Constituent Profiling of Paecilomyces cicadae Liquid Fermentation for Astragli Radix

Astragli Radix (AR) is one of the most popular traditional Chinese medicines with chemical constituents including flavonoids and saponins. As recently evidenced, some fungi or their fermentation liquid may have the potential to affect the bioactive constituents and different pharmacological effects of AR. Thus, the composition of fermented AR (FAR) produced by Paecilomyces cicadae (Miquel) Samson in liquid-state fermentation was investigated using a UHPLC-LTQ-Orbitrap mass spectrometer in both positive and negative ion modes. Firstly, the MSⁿ data sets were obtained based on a data-dependent acquisition method and a full scan–parent ions list–dynamic exclusion (FS-PIL-DE) strategy. Then, diagnostic product ions (DPIs) and neutral loss fragments (NLFs) were proposed for better constituent detection and structural characterization. Consequently, 107 constituents in total, particularly microconstituents in FAR and AR, were characterized and compared in parallel on the same LTQ–Orbitrap instrument. Our results indicated that AR fermentation with Paecilomyces significantly influenced the production of saponins and flavonoids, especially increasing the content of astragaloside IV. In conclusion, this research was not only the first to show changes in the chemical components of unfermented AR and FAR, but it also provides a foundation for further studies on the chemical interaction between microbiota and AR.