Hui-Xia Huo

Characterization and quantitative analysis of phenylpropanoid amides in eggplant (Solanum melongena L.) by high performance liquid chromatography coupled with diode array detection and hybrid ion trap time-of-flight mass spectrometry.

Eggplant (Solanum melongena L.) is a famous edible and medicinal plant. Despite being widely cultivated and used, data on certain parts other than the fruit are limited. The present study focused on the qualitative and quantitative analysis of the chemical constituents, particularly phenylpropanoid amides (PAs), in eggplant. The mass fragmentation patterns of PAs were proposed using seven authentic compounds with the assistance of a hybrid ion trap time-of-flight mass spectrometer. Thirty-seven compounds (27 PAs and 10 others) were detected and plausibly assigned in the different parts of eggplant. Afterward, a reliable method based on liquid chromatography coupled with diode array detection was developed, validated, and applied for the simultaneous determination of seven PAs and three caffeoylquinic acids in 17 batches of eggplant roots with satisfactory accuracy, precision, and reproducibility, which could not only provide global chemical insight of eggplant but also offer a reliable tool for quality control.

Anti-inflammatory lignanamides from the roots of Solanum melongena L.

Four new lignanamides, melongenamides A-D (1-4), together with six known ones (5-10), were isolated from the roots of Solanum melongena L. Their structures were elucidated on the basis of 1D and 2D NMR experiments and by comparison of their spectroscopic and physical data with the literature values. Compounds 2-8 exhibited inhibitions of nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages with IC50 values ranging from 16.2 to 58.5 μM.

Anti-neuroinflammatory sesquiterpenes from Chinese eaglewood.

Nine new sesquiterpenes (1-9), together with seventeen known ones (10-26), were isolated from Chinese eaglewood. Their structures were established by extensive spectroscopic analysis, and the absolute configuration of 6 was determined by the modified Moshers method. Compounds 7, 10, 14, 15, and 21 exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated BV-2 microglial cells with IC50 values in the range 7.1-53.8 μM.

Anti-inflammatory 2-(2-phenylethyl)chromone derivatives from Chinese agarwood.

Five new 2-(2-phenylethyl)chromone derivatives (1-5), along with eleven known compounds (6-16) were isolated from Chinese agarwood. Their structures were elucidated by spectroscopic data (NMR, UV, IR, and MS) analyses and comparison of their spectroscopic and physical data with the literature values. The absolute configurations of 2-4 were determined by electronic circular dichroism (ECD) calculations. Compounds 2-4, 11, 12, and 15 exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 cells with IC50 values in the range 1.6-7.3μM.

HHX-5, a derivative of sesquiterpene from Chinese agarwood, suppresses innate and adaptive immunity via inhibiting STAT signaling pathways.

Induction of excessive, prolonged, or dysregulated immune responses causes immunological disorders, such as inflammatory diseases, autoimmune diseases, allergic diseases, and organ-graft rejections. In the present study, we investigated the inhibitory effects of HHX-5, a derivative of sesquiterpene from Chinese agarwood, on innate and adaptive immunity for revealing its potential to treat above immunological disorders. The results showed that HHX-5 significantly inhibited the activation of macrophages and neutrophils which play important roles in innate immunity. Furthermore, HHX-5 strongly suppressed adaptive immunity via inhibiting differentiation of naive CD4+ T cells into Th1, Th2, and Th17 cells and suppressing activation, proliferation and differentiation of CD8+ T cells and B cells. The mechanism study showed that HHX-5 significantly inhibited STAT1 signaling pathway in macrophages and suppressed STAT1, STAT4, STAT5, and STAT6 signaling pathways in naive CD4+ T cells. In conclusion, we demonstrated that HHX-5 can strongly inhibit innate and adaptive immunity via suppressing STAT signaling pathways and has potential to be developed into therapeutic drug for treat immunological disorders.

GYF-21, an Epoxide 2-(2-Phenethyl)-Chromone Derivative, Suppresses Innate and Adaptive Immunity via Inhibiting STAT1/3 and NF-κB Signaling Pathways

Multiple sclerosis is a chronic inflammatory autoimmune disease of the central nervous system characterized by demyelinating plaques and axonal loss. Inhibition on over activation of innate and adaptive immunity provides a rationale strategy for treatment of multiple sclerosis. In the present study, we investigated the inhibitory effects of GYF-21, an epoxide 2-(2-phenethyl)-chromone derivative isolated from Chinese agarwood, on innate and adaptive immunity for revealing its potential to treat multiple sclerosis. The results showed that GYF-21 markedly inhibited the activation of microglia, and dendritic cells as well as neutrophils, all of which play important roles in innate immunity. Furthermore, GYF-21 significantly suppressed adaptive immunity via inhibiting the differentiation of naive CD4+ T cells into T helper 1 (Th1) and T helper 17 (Th17) cells, and suppressing the activation, proliferation, and IFN-γ secretion of CD8+ T cells. The mechanism study showed that GYF-21 evidently inhibited the activation of STAT1/3 and NF-κB signaling pathways in microglia. In conclusion, we demonstrated that GYF-21 can significantly inhibit innate and adaptive immunity via suppressing STAT1/3 and NF-κB signaling pathways, and has potential to be developed into therapeutic drug for multiple sclerosis.

Anti-inflammatory Dimeric 2-(2-Phenylethyl)chromones from the Resinous Wood of Aquilaria sinensis

Sixteen new 2-(2-phenylethyl)chromone dimers, including four pairs of enantiomers (1a/1b, 3a/3b, 6a/6b, and 8a/8b), along with eight optically pure analogues (2, 4, 5, 7, and 9-12) were isolated from the resinous wood of Aquilaria sinensis. Their structures were determined by extensive spectroscopic analysis (1D and 2D NMR, UV, IR, and HRMS) and experimental and computed ECD data. Compounds 1-10 feature an unusual 3,4-dihydro-2 H-pyran ring linkage connecting two 2-(2-phenylethyl)chromone monomeric units, while compounds 11 and 12 possess an unprecedented 6,7-dihydro-5 H-1,4-dioxepine moiety in their structures. A putative biosynthetic pathway of the representative structures via a diepoxy derivative of a chromone with a nonoxygenated A-ring is also proposed. Compounds 1a/1b, 2, 3a/3b, 5, 7, 8a/8b, and 10-12 exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells with IC50 values in the range 7.0-12.0 μM.

Method development and application for multi-component quantification in rats after oral administration of Longxuetongluo Capsule by UHPLC–MS/MS

Graphical abstract Figure. No caption available. HighlightsAn UHPLC–MS/MS method of 11 phenolic compounds in rat plasma and tissues was developed.Identity confirmation was carried out via SRM‐MS/MS mode on a Qtrap‐MS.The method was applied for the pharmacokinetic and tissue distribution studies in rats.The findings provide solid information for the understanding of the effective substances of LTC. ABSTRACT Although wide applications towards ischemic stroke in clinic, the therapeutic materials of Longxuetongluo Capsule (LTC) that is composed of total phenolic extract of Chinese dragons blood, are still largely unclear. Exposure pattern characterization of those drug‐derived components in vivo, notably in circulation system has been recommended as a viable approach to disclose the effective components of a given herbal medicine. Herein, we aimed to develop a robust method being capable of multi‐component quantification in either rat plasma or tissues following oral administration of LTC, and to clarify the kinetic profiles of 11 primary drug‐derived phenolic derivatives. Proteins precipitation was carried out for the plasma as well as homogenized tissue samples with acetonitrile. Chromatographic separations were achieved using UHPLC equipped with a shim‐pack XR‐ODS II column, and confidence‐enhanced detection was accomplished through the joint employment of selected‐reaction monitoring and tandem mass spectrometry (SRM‐MS/MS) on a hybrid triple quadrupole‐linear ion trap mass spectrometer. Diverse validation assays proved the method to be sensitive, precise, and rapid for simultaneous determination of those 11 components. Pharmacokinetic and tissue distribution investigations were subsequently conducted in rat after a single 500 mg/kg oral dose. Rapid absorption (Tmax, 11.53–68.27 min) and elimination (T1/2, 6.893–57.90 min) occurred for all analytes‐of‐interest. Extensive occurrences were observed for 7,4′‐dihydroxy‐5‐methoxyhomoisoflavanone (Cmax, 340.0 ng/mL), thevetiaflavone (Cmax, 42.86 ng/mL), 5,7,4′‐trihydroxyhomoisoflavanone (Cmax, 41.55 ng/mL), and pterostilbene (Cmax, 25.49 ng/mL) in plasma. Significant distributions occurred for all analytes in the liver as well as kidney, and several compounds could be found in brain. The findings described are envisioned to provide promising information for the in‐depth clarification of the therapeutic entities, and also to offer a practical approach for therapeutic drug monitoring of LTC in clinic.

Definitely simultaneous determination of three lignans in rat using ultra-high performance liquid chromatography-tandem mass spectrometry

Herbal medicines (HMs) have been widely demonstrated to be extremely complicated chemical pools, notably the occurrences of isomers that usually possess similar chromatographic and spectrometric behaviors, and the complexity will be further boosted in HMs-treated biological samples. Hence, there is a technical barrier regarding identity confirmation towards the acquisition of reliable quantitative information for those compounds-of-interest in biological matrices, although tandem mass spectrometry (MS/MS) is a favored tool because of the advantages in terms of specificity and selectivity, in particular being hyphenated with ultra-high performance liquid chromatography (UHPLC). More structural information should be involved in addition to retention times and precursor-to-product ion transitions, to consolidate the identities of the captured signals. Attempts were made here to strengthen quantitation confidences via matching MS2 spectra and relative response-collision energy curves (RRCECs) between each pair of suspect peak and the authentic signal, and UHPLC coupled to hybrid triple quadrupole-linear ion trap mass spectrometry (Qtrap-MS) that enabled simultaneous acquisition of qualitative and quantitative information acted as the analytical tool. Definitely simultaneous determination of a pair of regio-isomers namely 6‑hydroxy‑4‑(4‑hydroxy‑3‑methoxyphenyl)‑3‑hydroxymethyl‑7‑methoxy‑3,4‑dihydro‑2‑naphthaldehyde (VB-1) and vitedoin A (VB-2), together with another analogue namely detetrahydroconidendrin (VB-3), in rat plasma as well as tissues was conducted following oral administration of the extract of fruits of Vitex negundo var. cannabifolia. Diverse method validation assays in regard of selectivity, linearity, intra- and inter-day variations, matrix effect, and recovery were employed to demonstrate the newly developed method being able to fulfill the demands of rational quantitation. Overall, the current study offers a promising approach to accomplish confidence-enhanced quantitation in biological matrices.

A full solution for multi-component quantification-oriented quality assessment of herbal medicines, Chinese agarwood as a case

The quality of herbal medicines (HMs) is the prerequisite for their pronounced therapeutic outcomes in clinic, and multi-component (also known as quality markers, Q-markers) quantification has been widely emphasized as a viable means for quality evaluation. Because of the chemical diversity, the quality control practices are extensively dampened by four principal technical bottlenecks, including the lack of authentic compounds, large polarity span, extensive concentration range, and signal misrecognition for those potential Q-markers. An attempt to promote the potential of LC-MS/MS is made herein to cope with those obstacles and Chinese agarwood was employed as a case study. Firstly, a home-made fraction collector was introduced to automatically fragment the entire extract into a panel of fractions-of-interest. Secondly, quantitative 1H-NMR was deployed to offset the LC-MS/MS potential towards in-depth chemical profiling each fraction, and those well-defined fractions were then pooled and combined with some accessible authentic compounds to generate the pseudo-mixed standard solution. Thirdly, serial improvements were conducted for LC-MS/MS measurements. Reversed phase LC and hydrophilic interaction LC were serially coupled in respond to the large polarity window, and online parameter optimization, response tailoring, as well as RRCEC (relative response vs. collision energy curve) matching were integrated in MS/MS domain to advance the quantitative confidences. Simultaneous determination was conducted for 26 components, in total, in Chinese agarwood after method validation. In particular, authentic compound-free quantification was achieved for eight 2-(2-phenylethyl)chromone derivatives. Above all, the strategy is a promising solution to completely tackle with the technical barriers toward Q-marker quantification-oriented quality control of Chinese agarwood, as well as other HMs.