Simultaneous determination of tectorigenin and its metabolites in rat plasma by ultra performance liquid chromatography/quadrupole time-of-flight mass spectrometry

Study on quality difference between Belamcanda chinensis (L.) DC and Iris tectorum Maxim. based on chemical chromatogram analysis, biological activity evaluation and in vivo distribution rule

ETHNOPHARMACOLOGICAL RELEVANCE

Belamcanda chinensis (L.) DC. (BC) and Iris tectorum Maxim. (ITM) have been widely used in recent years due to their remarkable curative effects on sore throat, cough and asthma. but they are often misused due to their similar appearance. A comprehensive comparison of the chemical composition, biological activity, pharmacokinetics and tissue distribution between the two active differential components has not been performed. Differences in their specific effects have not been fully elucidated.

AIM OF THE STUDY

This work aims at differentiating between BC and ITM in terms of appearance, chemical composition, biological activity, pharmacokinetics and tissue distribution.

MATERIALS AND METHODS

In this study, the HPLC-FP method was used to find the differences between the chemical components of BC and ITM. The pharmacological experiments were used to compare the differences in activity, including in vitro anti-inflammatory activity with LPS-induced inflammation model of RAW 264.7 cells, inhibition of AChE activity, and the regulation of isolated small intestinal smooth muscle in mice. The pharmacokinetic and tissue distribution profiles were used to analyze the differences between the two in rats.

RESULTS

The types of isoflavones in BC and ITM are basically the same, but their contents in ITM is much higher than that in BC. At the same doses, the release of TNF-α, NO, IL-1β and IL-6 from RAW 264.7 cells in the ITM group was lower than that of the BC group, and the in vitro anti-inflammatory activity of ITM was stronger than that of BC. Meanwhile, ITM had stronger inhibition ability to inhibit AChE activity than BC. The BC extract exhibited an inhibitory effect on the isolated small intestinal smooth muscle of mice, and the ITM extract showed stimulatory effect at low concentration and inhibitory effect at high concentration. There were significant differences in drug-time profiles, kinetic parameters and tissue distribution.

CONCLUSIONS

There are significant differences in the multidimensional aspects of appearance, chemical composition, biological activity, pharmacokinetics, and tissue distribution between BC and ITM. This study provides a theoretical basis for the quality control, pharmacological efficacy and clinical application of the two herbs.

Tectorigenin: A Review of Its Sources, Pharmacology, Toxicity, and Pharmacokinetics

Tectorigenin is a well-known natural flavonoid aglycone and an active component that exists in numerous plants. Growing evidence suggests that tectorigenin has multiple pharmacological effects, such as anticancer, antidiabetic, hepatoprotective, anti-inflammatory, antioxidative, antimicrobial, cardioprotective, and neuroprotective. These pharmacological properties provide the basis for the treatment of many kinds of illnesses, including several types of cancer, diabetes, hepatic fibrosis, osteoarthritis, Alzheimer's disease, etc. The purpose of this paper is to provide a comprehensive summary and review of the sources, extraction and synthesis, pharmacological effects, toxicity, pharmacokinetics, and delivery strategy aspects of tectorigenin. Tectorigenin may exert certain cytotoxicity, which is related to the administration time and concentration. Pharmacokinetic studies have demonstrated that the main metabolic pathways in rats for tectorigenin are glucuronidation, sulfation, demethylation and methoxylation, but that it exhibits poor bioavailability. From our perspective, further research on tectorigenin should cover: exploring the pharmacological targets and mechanisms of action; finding an appropriate concentration to balance pharmacological effects and toxicity; attempting diversified delivery strategies to improve the bioavailability; and structural modification to obtain tectorigenin derivatives with higher pharmacological activity.

Preclinical studies of toxicity and anti-cholangiocarcinoma activity of the standardized capsule formulation of Atractylodes lancea (Thunb.) DC

BACKGROUND

Cholangiocarcinoma (CCA), the adenocarcinoma of the biliary duct, is commonly reported in Asia, with the highest incidence in northeastern Thailand. Chemotherapy of CCA has been limited by the lack of effective chemotherapeutic drugs. A series of previous in vitro and in vivo studies support further research and development of Atractylodes lancea (Thunb.) DC. (AL) as a potential candidate for treating CCA as a crude ethanolic extract. In the present study, we evaluated the toxicity and anti-CCA activity of the CMC (Chemistry, Manufacturing, and Control) capsule formulation of the ethanolic rhizome extract of AL (CMC-AL) in animals.

METHODS

Major steps included acute, subchronic and chronic toxicity testing in Wistar rats and anti-CCA activity in a CCA-xenografted nude mouse model. The safety of CMC-AL was determined based on the maximum tolerated dose (MTD) and no-observed-adverse-effect level (NOAEL) according to the OECD guideline. The anti-CCA activity of CMC-AL in nude mice was evaluated after transplantation of CL-6 cells to evaluate inhibitory effects on tumor size progression and metastasis and survival time prolongation. Safety assessments included hematology, biochemistry parameters and histopathological examination. Lung metastasis was investigated using VEGF ELISA kit.

RESULTS

All evaluations confirmed satisfactory pharmaceutical properties of oral formulation and safety profile of the CMC-AL with no overt toxicity up to the MTD and NOAEL of 5,000 and 3,000 mg/kg body weight, respectively. CMC-AL exhibited potent anti-CCA efficacy with regard to inhibitory activity on tumor progression and lung metastasis.

CONCLUSIONS

CMC-AL is safe and should be further investigated in a clinical trial as a potential therapy for CCA patients.

Oriental traditional herbal Medicine--Puerariae Flos: A systematic review

ETHNOPHARMACOLOGICAL RELEVANCE

Pueraria Flos (PF), a traditional herbal medicine, is botanically from the dried flowers of Pueraria lobate (Willd.) Ohwi. (Chinese: ) or Pueraria thomsonii Benth. (Chinese: ). It has a long history of thousands of years in China for awakening the spleen, clearing the lungs, relieving alcohol.

AIM OF THE REVIEW

This review aims to report the up-to-date research progress in ethnopharmacology, phytochemistry, pharmacology and toxicology, metabolism and therapeutic application of PF, so as to provide a strong basis for future clinical treatment and scientific research.

MATERIALS AND METHODS

Relevant information on PF was collected from scientific literature databases including PubMed, CNKI and other literature sources (Ph.D. and M.Sc. dissertations and Chinese herbal classic books) by using the keyword "Puerariae".

RESULTS

Briefly, phytochemical research report has isolated 39 flavonoids, 19 saponins and 25 volatile oils from PF. Flavonoids and saponins are the most important bioactive compounds, and most of the quality control studies focus on these two types of compounds. Modern pharmacological studies have revealed their significant biological activities in relieving alcoholism, hepatoprotective, anti-tumor, anti-inflammatory, and anti-oxidation, which provides theoretical support for the traditional use.

CONCLUSIONS

Comprehensive analysis showed that pharmacological activity of most purified compounds from PF had not been reported. Kakkalide, tectoridin and their deglycosylated metabolites (irisolidone and tectorigenin) has been focused on excessively due to their higher content and better activities. This leads to low development and resources waste. Interestingly, PF made a breakthrough in the field of food. Many kinds of fat-lowering foods such as PILLBOX Onaka have been popular in Japan market, which received extensive attention. Therefore, we suggest that future research can be paid attention on the development of the plant's function in the field of food and medicine, as well as the transformation from experimental to clinical.

Systematic characterization of Puerariae Flos metabolites in vivo and assessment of its protective mechanisms against alcoholic liver injury in a rat model

Puerariae Flos, a representative homology plant of medicine and food for alcoholism, has a long history of clinical experience and remarkable curative effect in the treatment of alcoholic liver disease (ALD). However, its effective forms and hepatoprotective mechanisms remain unknown. In the present study, a strategy based on UPLC-QTOF MS combined with mass defect filtering technique was established for comprehensive mapping of the metabolic profile of PF in rat plasma, urine, bile, and feces after oral administration. Furthermore, the absorbed constituents into plasma and bile with a relatively high level were subjected to the network analysis, functional enrichment analysis, and molecular docking to clarify the potential mechanism. Finally, the therapeutic effect of PF on ALD and predicted mechanisms were further evaluated using a rat model of alcohol-induced liver injury and Western blot analysis. In total, 25 prototype components and 82 metabolites, including 93 flavonoids, 13 saponins, and one phenolic acid, were identified or tentatively characterized in vivo. In addition, glucuronidation, sulfation, methylation, hydroxylation, and reduction were observed as the major metabolic pathways of PF. The constructed compound–target–pathway network revealed that 11 absorbed constituents associated with the 16 relevant targets could be responsible for the protective activity of PF against ALD by regulating nine pathways attributable to glycolysis/gluconeogenesis, amino acid metabolism, and lipid regulation as well as inflammation and immune regulation. In addition, four active ingredients (6″-O-xylosyltectoridin, genistein-7-glucuronide-4′-sulfate, tectoridin-4′-sulfate, and 6″-O-xylosyltectoridin-4′-sulfate) as well as two target genes (MAO-A and PPAR-α) were screened and validated to play a crucial role with a good molecular docking score. The present results not only increase the understanding on the effective form and molecular mechanisms of PF-mediated protection against ALD but also promote better application of PF as a supplement food and herbal medicine for the treatment of ALD.

Urinary excretion of silibinin diastereoisomers and their conjugated metabolites in rat and human at different dosages

Silibinin is a mixture of two flavonoid lignan silibinins A and B from the seeds of milk thistle (Silybum marianum L.). Using UPLC/Q-TOFMS, a total of 18 metabolites were identified in rat and human urine samples after oral administration of Silibinin Capsule. Furthermore, nine glucuronides and/or sulfated metabolites and two prototype compounds were simultaneously quantified in rat urine after oral administration of Silibinin Capsule at 50 and 100 mg/kg. Over a 72-h period, 27.6% and 23.3% of the silibinin were excreted in the forms of eleven metabolites in urine, among which, 5 major metabolites, including silibinin A-7-O-β-glucuronide (SA-7G), silibinin B-7-O-β-glucuronide (SB-7G), silibinin A-5-O-β-glucuronide (SA-5G), silibinin B-5-O-β-glucuronide (SB-5G) and silibinin A-20-O-glucuronide (SA-20G), accounted for 20.5% and 15.5% of the dosages separatively at doses of 50 and 100 mg/kg. These results suggested that glucuronidation at the C7-, C5- and C20- hydroxyls was the primary metabolic pathway of silibinin diastereoisomers in vivo. The present results provide helpful information for in vivo metabolism and clinical usage of Silibinin Capsule.

UGT1A1 and UGT1A9 Are Responsible for Phase II Metabolism of Tectorigenin and Irigenin In Vitro

Tectorigenin and irigenin are biologically active isoflavones of Belamcanda chinensis (L.) DC. Previous studies indicated that both compounds could be metabolized in vivo; however, the kinetic parameters of enzymes involved in the metabolization of tectorigenin and irigenin have not been identified. The aim of this study was to investigate UGTs involved in the glucuronidation of tectorigenin and irigenin and determine enzyme kinetic parameters using pooled human liver microsomes (HLMs) and recombinant UGTs. Glucuronides of tectorigenin and irigenin were identified using high-performance liquid chromatography (HPLC) coupled with mass spectrometry and quantified by HPLC using a response factor method. The results showed that tectorigenin and irigenin were modified by glucuronidation in HLMs. One metabolite of tectorigenin (M) and two metabolites of irigenin (M1 and M2) were detected. Chemical inhibition and recombinant enzyme experiments revealed that several enzymes could catalyze tectorigenin and irigenin glucuronidation. Among them, UGT1A1 and UGT1A9 were the primary enzymes for both tectorigenin and irigenin; however, the former mostly produced irigenin glucuronide M1, while the latter mostly produced irigenin glucuronide M2. These findings suggest that UGT1A1 and UGT1A9 were the primary isoforms metabolizing tectorigenin and irigenin in HLMs, which could be involved in drug–drug interactions and, therefore, should be monitored in clinical practice.

Pharmacokinetics, Prostate Distribution and Metabolic Characteristics of Four Representative Flavones after Oral Administration of the Aerial Part of Glycyrrhiza uralensis in Rats

(1) Background: The aerial part of G. uralensis had pharmacological effects against chronic non-bacterial prostatitis (CNP), and flavonoids are the main efficacy components. The purpose of this study was to obtain the pharmacokinetics, prostate distribution and metabolic characteristics of some flavonoids in rats. (2) Methods: The prototype flavones and the metabolites of four representative flavonoids, namely puerarin, luteolin, kaempferol and pinocembrin in plasma, prostate, urine and feces of rats were analyzed by UPLC-Q-Exactive Orbitrap-MS. In addition, the pharmacokinetic parameters in plasma and distribution of prostate of four components were analyzed by HPLC-MS/MS. (3) Results: In total, 22, 17, 22 and 11 prototype flavones were detected in the prostate, plasma, urine and feces, respectively. The metabolites of puerarin in the prostate are hydrolysis and glucose-conjugated products, the metabolites of kaempferol and luteolin in the prostate are methylation and glucuronidation, and the metabolites of pinocembrin in the prostate are naringenin, oxidation, sulfation, methylation and glucuronidation products. The t1/2 of puerarin, luteolin, kaempferol and pinocembrin was 6.43 ± 0.20, 31.08 ± 1.17, 18.98 ± 1.46 and 13.18 ± 0.72 h, respectively. The concentrations of the four flavonoids in prostate were ranked as kaempferol > pinocembrin > luteolin > puerarin. (4) Conclusions: Methylation and glucuronidation metabolites were the main metabolites detected in the prostate. A sensitive and validated HPLC−MS/MS method for simultaneous determination of puerarin, luteolin, kaempferol and pinocembrin in rat plasma and prostate was described, and it was successfully applied to the pharmacokinetic and prostate distribution studies.

Pharmacokinetics of tectorigenin, tectoridi, irigenin, and iridin in mouse blood after intravenous administration by UPLC-MS/MS

Tectorigenin, tectoridin, irigenin, and iridin are the four most predominant compounds present in She Gan. She Gan has been used in traditional Chinese medicine because of its anti-inflammatory, hepatoprotective, anti-tumor, antioxidant, phytoestrogen-like properties. In this paper, a UPLC-MS/MS method was developed to measure the pharmacokinetics of tectorigenin, tectoridin, irigenin, iridin after intravenous administration in mice. A UPLC BEH C18 (50 mm × 2.1 mm, 1.7 μm particle size) chromatographic column was utilized for separation of the four target analytes and internal standard (IS), and the analysis of blood plasma samples; the mobile phase consisted of an acetonitrile-water (w/0.1% formic acid) gradient elution. Electron spray ionization (ESI) positive-ion mode and multiple reaction monitoring (MRM) mode was used for quantitative analysis of the analytes and internal standard. The four compounds were administered intravenously (sublingual) at doses of 5 mg/kg. After blood sampling, samples were processed and then analyzed by UPLC-MS/MS. The linearity of the method was robust over the concentration range of 2–5,000 ng/mL. The intra-day precision of the analysis was within 15%, the inter-day precision was within 12%, and the accuracy was between 92% and 110%. The recoveries were 65–68%, and the matrix effect was 93–109%. The established UPLC-MS/MS detection method was then successfully applied to study the pharmacokinetics of tectorigenin, tectoridin, irigenin, iridin in mice.

Efficacy and Safety of Kudzu Flower-Mandarin Peel on Hot Flashes and Bone Markers in Women during the Menopausal Transition: A Randomized Controlled Trial

This randomized controlled study aimed to assess the efficacy and safety of an extract mixture of kudzu flower and mandarin peel (KM) on hot flashes (HFs) and markers of bone turnover in women during the menopausal transition. Healthy women aged 45–60 years with the menopausal HFs were randomly assigned in a 1:1 ratio to either KM (1150 mg/day) or placebo arms for 12 weeks (n = 84). The intent-to-treat analysis found that compared with the placebo, the KM significantly attenuated HF scores (p = 0.041) and HF severities (p < 0.001), with a mean difference from baseline to week 12. The KM also improved bone turnover markers, showing a significant reduction in bone resorption CTx (p = 0.027) and a tendency of increasing bone formation OC relative to the placebo. No serious adverse events and hormonal changes were observed in both groups. These findings suggest that KM consumption may improve the quality of life in ways that are important to symptomatic menopausal women.

Investigation of effect of tectorigenin (O-methylated isoflavone) on Ca2+ signal transduction and cytotoxic responses in canine renal tubular cells

Tectorigenin, a traditional Chinese medicine, is isolated from the flower of plants such as Pueraria thomsonii Benth. It is an O-methylated isoflavone, a type of flavonoid. Previous studies have shown that tectorigenin evoked various physiological responses in different models, but the effect of tectorigenin on cytosolic-free Ca²⁺ levels ([Ca²⁺]_i) and cytotoxicity in renal tubular cells is unknown. Our research explored if tectorigenin changed Ca²⁺ signal transduction and viability in Madin-Darby Canine Kidney (MDCK) renal tubular cells. [Ca²⁺]_iin suspended cells were measured by applying the fluorescent Ca²⁺-sensitive probe fura-2. Viability was explored by using water-soluble tetrazolium-1 as a fluorescent dye. Tectorigenin at concentrations of 5-50 μM induced [Ca²⁺]_irises. Ca²⁺ removal reduced the signal by approximately 20%. Tectorigenin (50 μM) induced Mn²⁺ influx suggesting of Ca²⁺ entry. Tectorigenin-induced Ca²⁺ entry was inhibited by 10% by three inhibitors of store-operated Ca²⁺ channels, namely, nifedipine, econazole, and SKF96365. In Ca²⁺-free medium, treatment with the endoplasmic reticulum Ca²⁺ pump inhibitor thapsigargin inhibited 83% of tectorigenin-evoked [Ca²⁺]_irises. Conversely, treatment with tectorigenin abolished thapsigargin-evoked [Ca²⁺]_irises. Inhibition of phospholipase C with U73122 inhibited 50% of tectorigenin-induced [Ca²⁺]_irises. Tectorigenin at concentrations between 10 and 60 μM killed cells in a concentration-dependent fashion. Chelation of cytosolic Ca²⁺ with 1,2-bis (2-aminophenoxy)ethane-N, N, N', N'-tetraacetic acid/acetoxy methyl did not reverse tectorigenin's cytotoxicity. Our data suggest that, in MDCK cells, tectorigenin evoked [Ca²⁺]_irises and induced cell death that was not associated with [Ca²⁺]_irises. Therefore, tectorigenin may be a Ca²⁺-independent cytotoxic agent for kidney cells.

Simultaneous determination of major components of Huangqi-Honghua extract in rat plasma using LC-MS/MS and application to a pharmacokinetic study

A sensitive and reliable LC-MS/MS method was developed and validated for simultaneous quantification of the major components of Huangqi-Honghua extact in rat plasma, including hydroxysafflor yellow A (HSYA), astragaloside IV (ASIV), calycosin-7-O-β-d-glucoside (CAG), calycosin, calycosin-3'-O-glucuronide (C-3'-G) and calycosin-3'-O-sulfate (C-3'-S). After extraction by protein precipitation with acetonitrile and methanol from plasma, the analytes were separated on a Hypersil BDS C₁₈ column by gradient elution with acetonitrile and 5 mM ammonium acetate. The detection was carried out on a triple quadrupole tandem mass spectrometer equipped with electrospray ionization source switched between negative and positive modes. HSYA was monitored in negative ionization mode from 0 to 4.9 min, and ASIV, CAG, calycosin, C-3'-G and C-3'-S were determined in positive ionization mode from 4.9 to 10 min. The lower limits of quantification of the analytes were 6.25 ng/mL for HSYA, 0.781 ng/mL for CAG and 1.56 ng/mL for ASIV and calycosin. The intra- and inter-assay precision (RSD) values were within 13.43%, and accuracy (RE) ranged from -8.75 to 9.92%. The validated method was then applied to the pharmacokinetic study of HSYA, ASIV, CAG, calycosin, C-3'-G and C-3'-S in rat after an oral administration of Huangqi-Honghua extract.

Characterization of in vitro metabolites of irisflorentin by rat liver microsomes using high-performance liquid chromatography coupled with tandem mass spectrometry

Belamcanda chinensis has been extensively used as antibechic, expectorant and anti-inflammatory agent in traditional medicine. Irisflorentin is one of the major active ingredients. However, little is known about the metabolism of irisflorentin so far. In this work, rat liver microsomes (RLMs) were used to investigate the metabolism of this compound for the first time. Seven metabolites were detected. Five of them were identified as 6,7-dihydroxy-5,3',4',5'-tetramethoxy isoflavone (M1), irigenin (M2), 5,7,4'-trihydroxy-6,3',5'-trimethoxy isoflavone (M3), 6,7,4'-trihydroxy-5,3',5'-trimethoxy isoflavone (M4) and 6,7,5'-trihydroxy-5,3',4'-trimethoxy isoflavone (M5) by means of NMR and/or HPLC-ESI-MS. The structures of M6 and M7 were not elucidated because they produced no MS signals. The predominant metabolite M1 was noted to be a new compound. Interestingly, it was found to possess anticancer activity much higher than the parent compound. The enzymatic kinetic parameters of M1 revealed a sigmoidal profile, with Vmax = 12.02 μm/mg protein/min, Km = 37.24 μm, CLint = 0.32 μL/mg protein/min and h = 1.48, indicating the positive cooperation. For the first time in this work, a new metabolite of irisflorentin was found to demonstrate a much higher biological activity than its parent compound, suggesting a new avenue for the development of drugs from B. chinensis, which was also applicable for other herbal plants. Copyright © 2016 John Wiley & Sons, Ltd.

Quantitative and qualitative analysis of the novel antitumor 1,3,4-oxadiazole derivative (GLB) and its metabolites using HPLC-UV and UPLC-QTOF-MS

Fructose-based 3-acetyl-2,3-dihydro-1,3,4-oxadiazole (GLB) is a novel antitumor agent and belongs to glycosylated spiro-heterocyclic oxadiazole scaffold derivative. This research first reported a simple, specific, sensitive and stable high performance liquid chromatography-ultraviolet detector (HPLC-UV) method for the quantitative determination of GLB in plasma. In this method, the chromatographic separation was achieved with a reversed phase C18 column. The calibration curve for GLB was linear at 300 nm. The lower limit of quantification was 10 ng/mL. The precision, accuracy and stability of the method were validated adequately. This method was successfully applied to the pharmacokinetic study in rats for detection of GLB after oral administration. Moreover, the structures of parent compound GLB and its two major metabolites M1 and M2 were identified in plasma using an ultra performance liquid chromatography-electrospray ionization-quadrupole-time of flight- mass spectrometry (UPLC-ESI-QTOF-MS) method. Our results indicated that the di-hydroxylation (M1) and hydroxylation (M2) of GLB are the major metabolites. In conclusion, the present study provided valuable information on an analytical method for the determination of GLB and its metabolites in rats, can be used to support further developing of this antitumor agent.