Simultaneous determination of five marker compounds in Xuanfu Daizhe Tang by high-performance liquid chromatography coupled with diode array detection for quality control

Xuanfu Daizhe Tang alleviates reflux esophagitis in rats by inhibiting the STAT1/TREM-1 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Reflux esophagitis (RE) is a common chronic inflammatory disease of the esophageal mucosa with a high prevalence and recurrence rate, for which a satisfactory therapeutic strategy is still lacking. Chinese medicine has its characteristics and advantages in treating RE, and the clinical application of Xuanfu Daizhe Tang (XDT) in treating RE has achieved sound therapeutic effects. However, there needs to be more research on its mechanism of action.

AIM OF THE STUDY

The present work aimed to investigate the mechanism of XDT action in RE through the Signal Transducer and Activator of Transcription 1 (STAT1)/Triggering Receptor Expressed on Myeloid cells-1 (TREM-1) pathway.

MATERIALS AND METHODS

The main active components of XDT were analyzed by ultra-performance liquid chromatography-mass spectrometer (UPLC-MS). The effect of XDT on RE was evaluated in a rat model of RE induced by "Cardioplasty + pyloric ligation + Roux-en-Y esophagojejunostomy". Each administration group was treated by gavage. The degree of damage to the esophageal mucosa was evaluated by visual observation, and the Potential of Hydrogen (PH) method and Hematoxylin-eosin staining (HE) staining were performed. Serum levels of Interleukin-1β (IL-1β), Interleukin-6 (IL-6), Tumor Necrosis Factor alpha (TNF-α), and Inducible Nitric Oxide Synthase (iNOS) were measured by ELISA. Quantitative Real-time PCR (qPCR), Western Blot (WB), and Immunofluorescence (IF) methods were used to detect Claudin-4, Claudin-5, TREM-1, and p-STAT1 in esophageal tissues for studying the mechanism of action and signaling pathway of XDT. Immunohistochemistry (IHC) analysis was used to detect the expression of TREM-1 and CD68 in esophageal tissues. Flow Cytometry (FC) was used to detect the polarization of macrophages in the blood. After conducting preliminary experiments to verify our hypothesis, we performed molecular docking between the active component of XDT and STAT1 derived from rats and parallel experiments with STAT1 inhibitor. The selective increaser of STAT1 transcription (2-NP) group was used to validate the mechanism by which XDT acts.

RESULTS

XDT alleviated esophageal injury and attenuated histopathological changes in RE rats. XDT also inhibited the inflammatory response and decreased serum IL-1β, IL-6, TNF-α, and iNOS levels in RE rats. qPCR and WB results revealed that XDT inhibited the expression of Claudin-4, Claudin-5, TREM-1, and STAT1 in the esophageal mucosa of RE rats. IHC and FC results showed that XDT reduced TREM-1 levels in esophageal tissues and polarized macrophages toward M2. The molecular docking results showed that rat-derived STAT1 can strongly bind to Isochronogenic acid A in XDT. The parallel experimental results of STAT1 inhibitor showed that XDT has anti-inflammatory effects similar to STAT1 inhibitors. The 2-NP group confirmed that XDT exerts its therapeutic effect on reflux esophagitis through the STAT1/TREM-1 pathway, with STAT1 as the upstream protein.

CONCLUSIONS

This study suggests that XDT may treat reflux esophagitis by modulating the STAT1/TREM-1 pathway.

Extraction optimization of accelerated solvent extraction for eight active compounds from Yaobitong capsule using response surface methodology: Comparison with ultrasonic and reflux extraction

This work described the development of a novel method for simultaneous extraction of eight active compounds (including catechin, albiflorin, paeoniflorin, ferulic acid, ginsenoside Rg1, tetrahydropalmatine, ginsenoside Rb1 and osthole) from Yaobitong capsule by accelerated solvent extraction (ASE). Response surface methodology (RSM) with desirability functions was employed to optimize the extraction conditions yielding the optimal conditions of ASE (extraction time 8 min, extraction temperature 80 °C, extraction solvent 70% methanol and flushing volume 100%). A high-performance liquid chromatography coupled with a diode array detector (HPLC-DAD) method was developed and validated for simultaneous quantification of the eight compounds in Yaobitong capsule. The values of correlation coefficient (R) were satisfactory between 0.9992 and 0.9999 over the linear concentration range of 0.5-1000 μg mL^-1. It was found that the limits of detection (LODs) and the limits of quantification (LOQs) for the eight active compounds were 0.10-2.90 μg•mL^-1 and 0.30-9.40 μg•mL^-1, respectively. The recoveries of the eight main active compounds in Yaobitong capsule were in the range of 93.31%-106.22%. And the contents of the analytes extracted by ASE under the optimal conditions were compared to traditional solvent extraction methods, such as ultrasonic and reflux extraction. The results indicated that the ASE method proved to be more suitable for the extract of active compounds in Yaobitong capsule, which could obtain higher extraction efficiency. At last, the proposed method was applied to analyze ten batches of actual samples, which provided high extraction efficiency and had wide potential application in the analysis of traditional Chinese medicines.

Simultaneous quantification of nine major active components in traditional Chinese prescription Mahuang decoction and the influence of herbal compatibility on their contents

Background:

Mahuang decoction (MHD), a famous classic traditional Chinese formula, has been extensively applied for treating cold, influenza, asthma, acute bronchitis, and other pulmonary diseases. However, the interaction among four drugs of MHD has not been clearly deciphered from the aspect of molecular composition.

Objective:

To assess the quality of MHD and explore the interplay among different prescription drugs.

Materials and Methods:

A reversed-phase high performance liquid chromatography (RP-HPLC) coupled with diode array detector (DAD) method for the simultaneous separation and determination of nine bioactive components was developed. A somatomedin A (SMA)-phenyl column (4.6 mm × 250 mm, 5 μm) was eluted by a gradient mobile phase contained acetonitrile and 0.05% formic acid-0.05% triethylamine aqueous solution. Four detection wavelengths (210, 252, 278, and 291 nm) were utilized for the quantitative analysis due to the different ultraviolet (UV) spectra of these compounds.

Results:

Satisfactory separation was obtained for all the components, and the assay was fully validated in respects of linearity, precision, stability, and accuracy. It was found that the calibration curves for all analytes showed good linearity (R²≥ 0.9991) within the test ranges. The relative standard deviations (RSDs) for intra- and interday repeatability were not more than 1.70 and 2.66%, respectively. The spike recoveries of nine components varied from 97.50 ± 1.69 to 99.27 ± 1.37%.

Conclusion:

The established method was successfully applied to analyze nine active compounds in decoction samples of various drug compatibilities of MHD. The variations of contents were obvious for different combinations, which hinted the mutual promotion or inhibition of componential dissolution among four herbs of MHD.