A sensitive and specific liquid chromatography/tandem mass spectrometry method for determination of echinacoside and its pharmacokinetic application in rats

Syringa microphylla Diels: A comprehensive review of its phytochemical, pharmacological, pharmacokinetic, and toxicological characteristics and an investigation into its potential health benefits

BACKGROUND

Syringa microphylla Diels is a plant in the family Syringa Linn. For hundreds of years, its flowers and leaves have been used as a folk medicine for the treatment of cough, inflammation, colds, sore throat, acute hepatitis, chronic hepatitis, early liver cirrhosis, fatty liver, and oesophageal cancer.

PURPOSE

For the first time, we have comprehensively reviewed information on Syringa microphylla Diels that is not included in the Pharmacopoeia, clarified the pharmacological mechanisms of Syringa microphylla Diels and its active ingredients from a molecular biology perspective, compiled in vivo and in vitro animal experimental data and clinical data, and summarized the toxicology and pharmacokinetics of Syringa microphylla Diels. The progress in toxicology research is expected to provide a theoretical basis for the development of new drugs from Syringa microphylla Diels, a natural source of compounds that are potentially beneficial to human health.

METHODS

The PubMed, Google Scholar, China National Knowledge Infrastructure, Web of Science, SciFinder Scholar and Thomson Reuters databases were utilized to conduct a comprehensive search of published literature as of July 2021 to find original literature related to Syringa microphylla Diels and its active ingredients.

RESULTS

To date, 72 compounds have been isolated and identified from Syringa microphylla Diels, and oleuropein, verbascoside, isoacteoside, echinacoside, forsythoside B, and eleutheroside B are the main active components. These compounds have antioxidant, antibacterial, anti-inflammatory, and neuroprotective effects, and their safety and effectiveness have been demonstrated in long-term traditional applications. Molecular pharmacology experiments have indicated that the active ingredients of Syringa microphylla Diels exert their pharmacological effects in various ways, primarily by reducing oxidative stress damage via Nrf2/ARE pathway regulation, regulating inflammatory factors and inducing apoptosis through the MAPK and NF-κB pathways.

CONCLUSION

This comprehensive review of Syringa microphylla Diels provides new insights into the correlations among molecular mechanisms, the importance of toxicology and pharmacokinetics, and potential ways to address the limitations of current research. As Syringa microphylla Diels is a natural low-toxicity botanical medicine, it is worthy of development and utilization and is an excellent choice for treating various diseases.

Multiple component-pharmacokinetic studies on 10 bioactive constituents of Peiyuan Tongnao capsule using parallel reaction monitoring mode

Peiyuan Tongnao capsule (PTC) plays an important role in clinical application due to its excellent curative efficacy in the treatment of ischemic stroke and chronic cerebral circulation insufficiency. To standardize and rationalize the clinical application of PTC, a rapid and sensitive method based on ultra-high performance liquid chromatography/quadrupole-Orbitrap mass spectrometry with parallel reaction monitoring (PRM) mode was developed and validated for the pharmacokinetic (PK) study. Ten bioactive compounds (aucubin, salidroside, echinacoside, paeoniflorin, verbascoside, liquiritin, 2,3,5,4'-tetrahydroxy stilbene-2-O-β-d-glucoside, coumarin, glycyrrhizic acid, and emodin) were simultaneously determined in rat plasma. All calibration curves exhibited good linearity (r²  > 0.99). The lower limits of quantification were 0.082-13.291 ng mL^-1 . The intra- and inter-day precision was 0.54-12.36%, whereas the intra- and inter-day accuracy ranged from 100.45 to 114.00%. The mean extraction recoveries were 81.77-117.66%, and the average matrix effects (MEs) were 86.23-109.96%. The high extraction recoveries and acceptable MEs indicated that the pretreatment method was feasible. And the stability was acceptable under various storage conditions and processing procedures. The validated method was successfully applied to the multiple components-PK studies, which lay the foundation for further pharmacological and clinical research of PTC and may provide a reference for other traditional Chinese medicines.

LC-MS-Based Qualitative Analysis and Pharmacokinetic Integration Network Pharmacology Strategy Reveals the Mechanism of Phlomis brevidentata H.W.Li Treatment of Pneumonia

Phlomis brevidentata H.W.Li Radix (PbR) is a rare traditional Tibetan medicine, and it is widely used in the Chinese Tibetan region for the treatment of pharyngitis, pneumonia, and so forth. Nevertheless, there is very little research on its modern pharmacy, and the active ingredients and mechanisms against these diseases remain unknown. In this study, we employed the qualitative analysis and pharmacokinetic based on LC-MS technology and network pharmacology to explore the active ingredients and mechanisms of PbR for treatment of pneumonia. Ultraperformance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-Q-TOF/MS) methodology was applied to identify the chemical composition of PbR. Meanwhile, a UPLC-MS/MS method was developed to quantify three active constituents (sesamoside, shanzhiside methyl ester, and barlerin) in rat plasma for the pharmacokinetic analysis after oral administration of PbR. Finally, in order to clarify the anti-pneumonia mechanism of this rare Tibetan medicine, a comprehensive network pharmacology strategy was applied. As a result, a total of 23 compounds were identified in PbR, including 14 iridoid glycosides, 7 phenylethanoid glycosides, and 2 other kinds of compounds. Pharmacokinetic studies have shown that the three compounds exhibit extremely similar pharmacokinetic characteristics, possibly due to their highly analogous chemical structure. We speculate that the iridoid glycosides may be the main active component in PbR. Then, the three iridoid glycoside constituents absorbed into blood were subjected to network pharmacology analysis for treatment of pneumonia. Compound-target-disease, gene ontology bioanalysis, KEGG pathway, and other network pharmacology analysis methods were applied to reveal that five main targets of the three iridoid glycosides, namely, GAPDH, ALB, MAPK1, AKT1, and EGFR, were significant in the regulation of the above bioprocesses and pathways. These results provide a basis for elucidating the bioactive compounds and the pharmacological mechanisms of P. brevidentata H.W.Li radix under clinical applications.

Therapeutic potential of phenylethanoid glycosides: A systematic review

Phenylethanoid glycosides (PhGs) are generally water-soluble phenolic compounds that occur in many medicinal plants. Until June 2020, more than 572 PhGs have been isolated and identified. PhGs possess antibacterial, anticancer, antidiabetic, anti-inflammatory, antiobesity, antioxidant, antiviral, and neuroprotective properties. Despite these promising benefits, PhGs have failed to fulfill their therapeutic applications due to their poor bioavailability. The attempts to understand their metabolic pathways to improve their bioavailability are investigated. In this review article, we will first summarize the number of PhGs compounds which is not accurate in the literature. The latest information on the biological activities, structure-activity relationships, mechanisms, and especially the clinical applications of PhGs will be reviewed. The bioavailability of PhGs will be summarized and factors leading to the low bioavailability will be analyzed. Recent advances in methods such as bioenhancers and nanotechnology to improve the bioavailability of PhGs are also summarized. The existing scientific gaps of PhGs in knowledge are also discussed, highlighting research directions in the future.

Phenylethanoid Glycosides: Research Advances in Their Phytochemistry, Pharmacological Activity and Pharmacokinetics

Phenylethanoid glycosides (PhGs) are widely distributed in traditional Chinese medicines as well as in other medicinal plants, and they were characterized by a phenethyl alcohol (C₆-C₂) moiety attached to a β-glucopyranose/β-allopyranose via a glycosidic bond. The outstanding activity of PhGs in diverse diseases proves their importance in medicinal chemistry research. This review summarizes new findings on PhGs over the past 10 years, concerning the new structures, their bioactivities, including neuroprotective, anti-inflammatory, antioxidant, antibacterial and antivirus, cytotoxic, immunomodulatory, and enzyme inhibitory effects, and pharmacokinetic properties.

Two-phase hollow fiber liquid phase microextraction based on magnetofluid for simultaneous determination of Echinacoside, Tubuloside B, Acteoside and Isoacteoside in rat plasma after oral administration of Cistanche salsa extract by high performance liquid chromatography

A new and fast sample preparation technique based on two-phase hollow fiber liquid phase microextraction (HF-LPME) with magnetofluid was developed to quantitate and determine the four phenylethanoid glycosides (PhGs) (Echinacoside, Tubuloside B, Acteoside and Isoacteoside) in plasma after oral administration of Cistanche salsa extract. Analysis was accomplished by reversed-phase high performance liquid chromatography (RP-HPLC) with ultraviolet detection. Parameters that affect the HF-LPME processes, such as the content of magnetic powder, the solvent type, salt content, stirring speed, extraction time and hollow fiber length, were investigated and optimized. Under the optimized conditions, the preconcentration factors for PhGs were higher than 625. The calibration curve for PhGs was linear in the range of 0.1-100ngmL(-1) with correlation coefficients greater than 0.9996. The intra-day and inter-day precision (RSD) were below 8.74% and the limits of detection (LOD) for the four PhGs were 8-15pgmL(-1) (S/N=3). The validated method was successfully applied to separate and determine the four PhGs in rat plasma after oral administration of C. salsa extract.

Simultaneous separation and determination of four phenylethanoid glycosides in rat plasma sample after oral administration of Cistanche salsa extract by microemulsion liquid chromatography

A simple, rapid and specific method was developed to separate as well as to determine the four phenylethanoid glycosides (PhGs) (echinacoside, tubuloside B, acteoside and isoacteoside) in rat plasma after oral administration of Cistanche salsa extract by reversed phase high performance liquid chromatography using a microemulsion as the mobile phase. The separations were performed on a Zorbax Extend-C18 column at 25°C. Photodiode-array detector was conducted at 322nm and with a flow rate of 0.8mLmin(-1). The optimized microemulsion mobile phase consisted of 0.3% triethylamine in 20mM phosphoric acid at pH 6.0, 0.8% (v/v) ethyl acetate as oil phase, 1.5% (v/v) Genapol X-080 as surfactant, 2.5% (v/v) n-propanol as co-surfactant. Under the optimal conditions, the calibration curve for four PhGs was linear in the range of 10-1000ngmL(-1) with the correlation coefficients greater than 0.9994. The intra-day and inter-day precision (RSD) were below 8.64% and the limits of detection (LOD) for the four PhGs were 0.4-1.3ngmL(-1) (S/N=3). The microemulsion liquid chromatography (MELC) method was successfully applied to separate and determine the four PhGs in rat plasma after oral administration of C. salsa extract.