HPLC/Q-TOF-MS-Based Identification of Absorbed Constituents and Their Metabolites in Rat Serum and Urine after Oral Administration ofCistanche deserticolaExtract

Network pharmacology combined with metabolomics and lipidomics to reveal the hypolipidemic mechanism of Alismatis rhizoma in hyperlipidemic mice

Alismatis rhizoma (AR), the dried rhizome of Alisma orientale (Sam) Juzep, is effective in treating hyperlipidemia, but the mechanisms involved require further exploration. This study evaluated the hypolipidemic properties of AR using an integrated strategy combining network pharmacology with metabolomics and lipidomics. Firstly, a hyperlipidemia mouse model induced by a high-fat diet was established to evaluate the therapeutic effects of AR. Secondly, plasma metabolomics and lipidomics were used to identify differential metabolites and lipids, and metabolic pathway analysis was performed using MetaboAnalyst. Thirdly, network pharmacology, based on the metabolic profile of AR in vivo, was used to discover potential therapeutic targets. Finally, key targets were obtained through a compound-target-metabolite network, which was verified by molecular docking and quantitative real-time PCR (qPCR). Biochemistry analysis and histological examinations showed that AR exerted hypolipidemic effects on hyperlipidemic mice. Seventy potential biomarkers for the AR treatment of hyperlipidemia were identified by metabolomics and lipidomics, which were mainly involved in lipid metabolism, energy metabolism and amino acid metabolism. Eighteen potentially active compounds were identified in the plasma of mice after oral administration of AR, which were associated with 83 potential therapeutic targets. The PPAR signaling pathway was considered a crucial signaling pathway of AR against hyperlipidemia by KEGG analysis. The joint analysis showed that 6 upstream key targets were regulated by AR, including ALB, TNF, IL1B, MMP9, PPARA and PPARG. Molecular docking showed that active compounds of AR had high binding affinity with these key targets. qPCR further demonstrated that AR could reverse the mRNA expression of these key targets in hyperlipidemic mice. This study integrates network pharmacology with metabolomics and lipidomics to reveal the regulatory effects of AR on endogenous metabolites and validates key therapeutic targets, and represents the most systematic and in-depth study on the hypolipidemic activity of AR.

Hypoglycemic and hypolipidemic effects of total glycosides of Cistanche tubulosa in diet/streptozotocin-induced diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Cistanche tubulosa (Schrenk) R. Wight (Orobanchaceae) is a frequently prescribed component in many traditional herbal prescriptions which are used to treat diabetes in China. In recent studies, the antidiabetic activity of Cistanche tubulosa extracts have been confirmed. However, no systematic investigation has been reported on the total glycosides of Cistatnche tubulosa (TGCT).

AIM OF THE STUDY

The present study aimed to investigate the hypoglycemic and hypolipidemic effects of TGCT and the potential mechanisms in diet/streptozotocin (STZ)-induced diabetic rats, and to chemically characterize the main constituents of TGCT.

MATERIALS AND METHODS

The major constituents of TGCT were characterized by HPLC/Q-TOF-MS and the analytical quantification was performed with HPLC-DAD. Type 2 diabetic rats were induced by high-fat high-sucrose diet (HFSD) and a single injection of STZ (30 mg/kg). TGCT (50 mg/kg, 100 mg/kg and 200 mg/kg) or metformin (200 mg/kg) were orally administered for 6 weeks. Body weight and calorie intake were monitored throughout the experiment. Fasting plasma glucose (FPG), oral glucose tolerance test (OGTT), area under curve of glucose (AUC-G), glycosylated hemoglobin (HbA1c), fasting insulin, serum C-peptide, glycogen content and insulin sensitivity index were tested. The levels of phosphorylated protein kinase B and phosphorylated glycogen synthase kinase 3β, the activities of hexokinase and pyruvate kinase were assayed. Meanwhile, the changes in serum lipid profiles, superoxide dismutase, glutathione peroxidase, malondialdehyde and inflammatory factors were measured. Histological of pancreas were also evaluated by haematoxylin-eosin stain.

RESULTS

Our investigation revealed the presence of phenylethanoid glycosides (PhGs): echinacoside (500.19 ± 11.52 mg/g), acteoside (19.13 ± 1.44 mg/g) and isoacteoside (141.82 ± 5.78 mg/g) in TGCT. Pharmacological tests indicated that TGCT significantly reversed STZ-induced weight loss (11.1%, 200 mg/kg); decreased FPG (56.4%, 200 mg/kg) and HbA1c (37.4%, 200 mg/kg); ameliorated the OGTT, AUC-G and insulin sensitivity; increased glycogen content (40.8% in liver and 52.6% in muscle, 200 mg/kg) and the activities of carbohydrate metabolizing enzymes; regulated lipid profile changes and the activities of antioxidant enzymes; diminished serum markers of oxidative stress and inflammation in a dose-dependent manner (p < 0.05).

CONCLUSIONS

This study confirmed that TGCT was an effective nutritional agent for ameliorating hyperglycemia and hyperlipidemia in diet/STZ-induced diabetic rats, which might be largely attributed to the activities of TGCT on inhibitions of oxidative stress and inflammation.

An integrated strategy toward comprehensive characterization and quantification of multiple components from herbal medicine: An application study in Gelsemium elegans

Objective

To develop a powerful integrated strategy based on liquid chromatography coupled with mass spectrometry (LC-MS) systems for the comprehensive characterization and quantification of multiple components of herbal medicines.

Methods

Firstly, different mobile phase additives, analysis time, and MS acquisition modes were orthogonally tested with liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC-QTOF/MS) in order to detect as many components of Gelsemium elegans as possible with high peak intensity. Secondly, several data mining strategies, including database searching, diagnostic ion filtering and neutral loss filtering, were utilized to perform chemical profiling. Subsequently, this study focused on the quantification and validation of the performance of a liquid chromatography-triple mass spectrometry (LC-QqQ/MS) assay based on derivative multiple reaction monitoring (DeMRM).

Results

A total of 147 components from G. elegans were characterized, among them 116 nontarget components were reported for the first time. A sensitive and reproducible LC-QqQ/MS method was successfully developed and validated for the simultaneous relative quantification of 41 components of G. elegans. This LC-QqQ/MS method was then applied to compare the contents of components in the roots, stems and leaves.

Conclusion

The present integrated strategy would significantly contribute to chemical studies on herbal medicine, and its utility could be extended to other research fields, such as metabolomics, quality control, and pharmacokinetics.

In Vitro and In Vivo Antioxidative Activity against Radiation-Induced Damage and the Systematic Chemical Components of Different Extracts of Lagotis brevituba Maxim

Lagotis brevituba Maxim is a perennial species distributed in the highlands of China, which has been used for more than 2000 years as a traditional Tibetan medicinal plant. However, no attention has been paid to the antioxidant activities of Lagotis brevituba Maxim in vitro or in vivo. Thus, this study aimed to evaluate the in vitro and in vivo antioxidant activity of Lagotis brevituba Maxim against radiation-induced damage as well as the systematic chemical components. To explore the relationship between the antioxidant activity and extraction solvent, Lagotis brevituba Maxim was extracted with three different solvents: methanol, water, and acetone. In antioxidant assays in vitro, the water extract had the strongest reducing power, 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity compared with the methanol and acetone extracts. However, the methanol extract was more potent in the β-carotene/linoleic acid cooxidation assay. In antioxidant assays in vivo, mice that were exposed to 6.0 Gy⁶⁰Co γ-ray whole-body radiation on day 15 after administration of Lagotis brevituba Maxim decreased their level of malondialdehyde (MDA) in a dose-dependent manner compared with the control group, indicating that Lagotis brevituba Maxim had favorable antioxidant activities in vivo. In addition, a total of 44 compounds were tentatively identified by liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS), including 19 flavonoids, 14 phenols, 8 phenylethanoid glycosides, 2 iridoid glycosides, and 1 carbohydrate. We obtained 25 compounds from plants in the genus Lagotis for the first time. These results suggested that Lagotis brevituba Maxim had potent antioxidant activity and could be explored as a novel natural antioxidant.

Exploring the In Vivo Existence Forms (23 Original Constituents and 147 Metabolites) of Astragali Radix Total Flavonoids and Their Distributions in Rats Using HPLC-DAD-ESI-IT-TOF-MSn

Astragali Radix total flavonoids (ARTF) is one of the main bioactive components of Astragali Radix (AR), and has many pharmacological effects. However, its metabolism and effective forms remains unclear. The HPLC-DAD-ESI-IT-TOF-MSⁿ technique was used to screen and tentatively identify the in vivo original constituents and metabolites of ARTF and to clarify their distribution in rats after oral administration. In addition, modern chromatographic methods were used to isolate the main metabolites from rat urine and NMR spectroscopy was used to elucidate their structures. As a result, 170 compounds (23 original constituents and 147 metabolites) were tentatively identified as forms existing in vivo, 13 of which have the same pharmacological effect with ARTF. Among 170 compounds, three were newly detected original constituents in vivo and 89 were new metabolites of ARTF, from which 12 metabolites were regarded as new compounds. Nineteen original constituents and 65 metabolites were detected in 10 organs. Four metabolites were isolated and identified from rat urine, including a new compound (calycoisn-3'-O-glucuronide methyl ester), a firstly-isolated metabolite (astraisoflavan-7-O-glucoside-2'-O-glucuronide), and two known metabolites (daidzein-7-O-sulfate and calycosin-3'-O-glucuronide). The original constituents and metabolites existing in vivo may be material basis for ARTF efficacy, and these findings are helpful for further clarifying the effective forms of ARTF.

Strategies for determining the bioactive ingredients of honey-processed Astragalus by serum pharmacochemistry integrated with multivariate statistical analysis

Honey-processed Astragalus is a widely used traditional Chinese medicine that has a better effect on reinforcing "Qi" (vital energy) than the raw one. A comparative study of metabolites analysis between them in rat serum for finding the bioactive ingredients was carried out using serum pharmacochemistry and multivariate statistical analysis. The blood collection methods and time were optimized first. Then the prototypes and metabolites in serum samples after oral administration were investigated by ultra-high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry integrated with principal component analysis and orthogonal partial least squares discriminant analysis. The contents of metabolites were also analyzed to evaluate the metabolic profile differences. As a result, nine prototypes and 36 metabolites were identified. Only two prototypes and 15 metabolites were different between raw and honey-processed Astragalus. Their biotransformation reactions contained the process of oxidation, demethylation, and hydrolysis in phase I and glucuronide conjugation or sulfate conjugation in phase II. Most of the detected metabolites were transformed from isoflavones and isoflavanes. Our results expand the knowledge about the influence of honey-processing on Astragalus and suggest the different curative effects between raw and honey-processed Astragalus might due to their therapeutic material discrepancy.

An Integrated Approach to Characterize Intestinal Metabolites of Four Phenylethanoid Glycosides and Intestinal Microbe-Mediated Antioxidant Activity Evaluation In Vitro Using UHPLC-Q-Exactive High-Resolution Mass Spectrometry and a 1,1-Diphenyl-2-picrylhydrazyl-Based Assay

Intestinal bacteria have a significant role in metabolism and the pharmacologic actions of traditional Chinese medicine active ingredients. Phenylethanoid glycosides (PhGs), as typical phenolic natural products, possess wide bioactivities, but low oral bioavailability. The aim of this work was to elucidate the metabolic mechanism underlying PhGs in the intestinal tract and screen for more active metabolites. In this study, a rapid and reliable method using an effective post-acquisition approach based on advanced ultra-high-performance liquid chromatography (UHPLC) coupled with hybrid Quadrupole-Orbitrap high resolution mass spectrometry (Q-Exactive-HRMS) provided full MS and HCD MS² data. Thermo Scientific™ Compound Discoverer™ software with a Fragment Ion Search (FISh) function in one single workflow was developed to investigate the intestinal microbial metabolism of four typical PhGs. Furthermore, antioxidant activity evaluation of PhGs and their related metabolites was simultaneously carried out in combination with a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay to understand how intestinal microbiota transformations modulate biological activity and explore structure–activity relationships (SARs). As a result, 26 metabolites of poliumoside, 42 metabolites of echinacoside, 42 metabolites of tubuloside, and 46 metabolites of 2′-acetylacteoside were identified. Degradation, reduction, hydroxylation, acetylation, hydration, methylation, and sulfate conjugation were the major metabolic pathways of PhGs. Furthermore, the degraded metabolites with better bioavailability had potent antioxidant activity that could be attributed to the phenolic hydroxyl groups. These findings may enhance our understanding of the metabolism, pharmacologic actions, and real active forms of PhGs.

Phytochemical screening and estrogenic activity of total glycosides of Cistanche deserticola

Over the decades, there have been continuous efforts to enhance the quality of human life. Postmenopausal syndrome is a serious concern for the wellbeing of a woman's health. Hormonal therapy is currently the mainstay of treatment for this condition. However, this therapy could lead to estrogen abuse, leading to adverse reactions and side effects. As a result, hormonal therapy has been unsuccessful in ameliorating postmenopausal syndrome. Cistanche deserticola is a classical tonic herb in traditional Chinese medicine. It exhibits significant estrogenic activity. The main active compounds of this herb are glycosides. In a previous experiment, three important factors contributing to the total glycoside yield, acteoside yield, and estrogenic activity were identified, namely, eluent concentration, pH, and eluent volume. In this experiment, an optimal purification process was determined using a central composite design-response surface methodology to obtain glycosides from this herb. An eluent (ethanol) concentration of 85% and volume of 25 BV at a pH of 11 was found to be optimal. Twenty-one active compounds were identified by a high-performance liquid chromatography/ quadrupole time-of-flight mass spectrometry assay. This study provides valuable insights for further in-depth research evaluating the estrogenic activities of total glycosides of Cistanche deserticola.

Comparison of the Chemical Profiles and Antioxidant Activities of Different Parts of Cultivated Cistanche deserticola Using Ultra Performance Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry and a 1,1-Diphenyl-2-picrylhydrazyl-Based Assay

In this study, a sensitive ultra-performance liquid chromatography-photodiode array coupled to quadruple time-of-flight mass (UPLC-PDA-Q/TOF-MS) method and a 1,1-diphenyl-2-picrylhydrazyl (DPPH)-based assay were used to determine the chemical constituents and screen the antioxidant activity profiles of the methanol extracts of different parts of cultivated Cistanche deserticola (C. deserticola). First, qualitative and quantitative chemical composition analyses of the different parts of cultivated C. deserticola were conducted. Obvious differences were observed between the chemical profiles and content distribution of phenylethanoid glycosides (PhGs) from the different cultivated C. deserticola parts. The average contents of the six PhGs parts varied from 4.91 to 72.56 mg/g DW (milligrams of extract per gram of plant dry weight) in the six different parts of Cistanche deserticola, displaying a significant decreasing trend from the bottom to the top of cultivated C. deserticola and the highest content in the stems. From the bottom to the top of the plant, the echinacoside and cistanoside A content decreased and the 2′-acetylacteoside content increased. Second, an offline DPPH assay revealed that the total scavenging activities of all parts within the range of 20–500 µg/mL increased in a concentration-dependent manner and that good antioxidant activities were found in all plant parts, particularly in the stems, which could be related to their higher PhG content. Additionally, a DPPH-UPLC-PDA method was successfully applied to rapidly screen the antioxidant profiles and antioxidant components of the different cultivated C. deserticola parts. According to the antioxidant profiles before and after the DPPH reaction, there were wide variations in the antioxidant activities of different cultivated C. deserticola parts. Moreover, the antioxidant profiles revealed the presence of major free radical scavengers identified as PhGs using UPLC-Q/TOF-MS. Finally, the established DPPH-UPLC-PDA method was reagent saving, rapid and feasible for correlating the chemical profile of traditional chinese medicines (TCMs) with their bioactivities without isolation and purification and may be used for multicomponent analysis of active substances in other foods and herbs. Therefore, to better harness C. deserticola resources, using this method to evaluate cultivated C. deserticola, a promising herb material with obvious antioxidant activity, is crucial.

Study of the estrogenic-like mechanism of glycosides of cistanche using metabolomics

Cistanche deserticola, known as Rou Cong-Rong in China, has been used as a tonic for more than 1800 years, with previous studies demonstrating that glycosides of cistanche (GCs) are a main active component.

Rapid screening and identification of the differences between metabolites of Cistanche deserticola and C. tubulosa water extract in rats by UPLC-Q-TOF-MS combined pattern recognition analysis

Cistanches Herba is a famous traditional Chinese medicine that has been in use for treating kidney deficiency, impotence, female infertility, morbid leucorrhea, profuse metrorrhagia, and senile constipation. With the exception of studies available for a few single active ingredients such as echinacoside, acteoside, and poliumoside, comprehensive and systematic studies on in vivo metabolism of Cistanches Herba are lacking despite its widespread clinical application. There is no comparative study yet on the metabolites resulting from the traditional usage of Cistanche deserticola and C. tubulosa water extract - two species that are recorded in Chinese Pharmacopoeia. This further restricts research on the therapeutic effect of Cistanches Herba to a great extent. In this study, a robust and unbiased UPLC-Q-TOF-MS combined pattern recognition analysis (orthogonal partial least squared discriminant analysis, OPLS-DA) was employed to rapidly screen prototype components and metabolites of C. deserticola and C. tubulosa water extract in rat urine, feces, and serum. A total of 71 metabolites from C. deserticola including 25 prototype components and 46 metabolites, and 45 metabolites from C. tubulosa including 18 prototype components and 27 metabolites were tentatively identified. Out of these, 10 metabolites were characterized for the first time in these two species. Results of this study indicate that phenylethanoid glycosides (PhGs) are mainly metabolized into degradation products in the gastrointestinal tract of rats. The chemical components cistanoside B, C, D, and E exist only in C. deserticola and release methylated hydroxytyrosol (HT) following metabolism. This factor contributes to the difference between metabolites of C. deserticola and C. tubulosa water extract in rats and is responsible for the differential therapeutic effect that these two species of Cistanches Herba have on the same diseases.