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Screening anaphylactic components of MaiLuoNing injection by using rat basophilic leukemia-2H3 cell membrane chromatography coupled with HPLC-ESI-TOF-MS.

MaiLuoNing injection is a traditional Chinese medicine that used clinically since the 1950s in China. However, anaphylactic reactions, through the potentiation of mast cell degranulation, have been reported. In the present study, a rat basophilic leukemia-2H3 cell membrane chromatography coupled with high-performance liquid chromatography and electrospray ionization-ion trap-time of flight-mass spectrometry method was established for screening, analyzing, and identifying the potential anaphylactic components of MaiLuoNing injection. Harpagoside, a potential degranulator of rat basophilic leukemia-2H3 cells, was retained in rat basophilic leukemia-2H3 cell membrane chromatography. We aimed to evaluate the retained components to determine which of those were capable of inducing degranulation of basophilic leukemia cells. A β-hexosaminidase assay revealed that harpagoside can induce rat basophilic leukemia-2H3 cell degranulation in a dose-dependent manner. BLBA/c mice also exhibit passive cutaneous anaphylaxis in response to harpagoside. These results indicate that rat basophilic leukemia-2H3 cell membrane chromatography coupled with high-performance liquid chromatography and electrospray ionization ion trap time-of-flight mass spectrometry is effective in screening for the anaphylactic components of MaiLuoNing injection.

Screening anti-allergic components of Astragali Radix using LAD2 cell membrane chromatography coupled online with UHPLC-ESI-MS/MS method

Huangqi (Astragali Radix), a traditional Chinese herb, is widely used in clinical therapy in China. In addition, an anti-allergic effect of constituents in Huangqi has been reported in the scientific literature. In the present study, cell membrane chromatography coupled online with UHPLC-ESI-MS/MS method was developed to screen, analyze and identify the anti-allergic components of Huangqi. The Laboratory of Allergic Disease 2 (LAD2) cell was used to establish cell membrane chromatography, which was combined with UHPLC-ESI-MS/MS. The coupled system was then used to screen anti-allergic components from Huangqi. Effects of active components were verified by histamine release assay. A component retained on the LAD2 cell membrane chromatography was identified as formononetin. Bioactivity of formononetin was investigated by histamine release assay in LAD2 cells, and it was found that formononetin could inhibit histamine release in a dose-dependent manner from 1 to 100 μm. The LAD2 cell membrane chromatography online with UHPLC-ESI-MS/MS method is an effective technique for screening the anti-allergic components of Huangqi.

Determine equilibrium dissociation constant of drug-membrane receptor affinity using the cell membrane chromatography relative standard method

The equilibrium dissociation constant (KD) of drug-membrane receptor affinity is the basic parameter that reflects the strength of interaction. The cell membrane chromatography (CMC) method is an effective technique to study the characteristics of drug-membrane receptor affinity. In this study, the KD value of CMC relative standard method for the determination of drug-membrane receptor affinity was established to analyze the relative KD values of drugs binding to the membrane receptors (Epidermal growth factor receptor and angiotensin II receptor). The KD values obtained by the CMC relative standard method had a strong correlation with those obtained by the frontal analysis method. Additionally, the KD values obtained by CMC relative standard method correlated with pharmacological activity of the drug being evaluated. The CMC relative standard method is a convenient and effective method to evaluate drug-membrane receptor affinity.

Typical antimicrobials induce mast cell degranulation and anaphylactoid reactions via MRGPRX2 and its murine homologue MRGPRB2

Mast cells are unique immune cells that function as sentinels in host defence reactions, including immediate hypersensitivity responses and allergic responses. The mast cell‐specific receptor named MAS‐related G protein‐coupled receptor X2 (MRGPRX2) triggers mast‐cell degranulation, a key process in anaphylactoid reactions. It is widely observed that antimicrobials can induce pseudo‐allergic reactions (i.e. IgE‐independent mechanism) with symptoms ranging from skin inflammation to life‐threatening systemic anaphylaxis. However, their direct involvement and the mechanisms underlying anaphylactoid reactions caused by antimicrobials have not been demonstrated. Structurally different antimicrobials were screened by Ca2+ imaging using MRGPRX2 overexpressing HEK293 cells. MRGPRX2 related anaphylactoid reactions induced by these components were investigated by body temperature drop and mast cell degranulation assays. We showed that MRGPRX2 is involved in allergic‐like reactions to three types of antimicrobials in a dose‐dependent manner. However, mast cells lacking the receptor show reduced degranulation. Furthermore, mice without MAS‐related G protein‐coupled receptor B2 (the orthologous gene of MRGPRX2) exhibited reduced substance‐induced inflammation. Interestingly, β‐lactam and antiviral nucleoside analogues did not induce anaphylactic reactions, which were also observed in vitro. These results should alarm many clinicians that such drugs might induce anaphylactoid reactions and provide guidance on safe dosage of these drugs.

Use of the relative release index for histamine in LAD2 cells to evaluate the potential anaphylactoid effects of drugs

Anaphylactoid reactions are common clinical acute adverse drug reactions that can exacerbate a patient’s condition and produce effects that may become life-threatening. Therefore, it is important to establish a novel method to evaluate drugs for anaphylactoid reactions. In this study, we developed a sensitive and rapid method to detect histamine release from LAD2 cells using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and constructed a relative release index based on various release curve parameters, including allergen release time and sudden change rate, to evaluate the potential and strength of allergen-induced anaphylactoid reactions. This LAD2 release model was used to evaluate anaphylactoid reactions induced by ciprofloxacin, norfloxacin, lomefloxacin, moxifloxacin, and baicalin. The results positively correlated with those obtained with an Evans blue ear test and negatively correlated with the Ca2+ influx EC50. In summary, the current study established a novel in vitro method to analyze the properties of histamine release from LAD2 cells and characterize the sensitization and strength of sensitization of drugs or components that may induce anaphylactoid reactions.

Screening allergic components of Yejuhua injection using LAD2 cell membrane chromatography model online with high performance liquid chromatography-ion trap-time of flight-mass spectrum system

Yejuhua (YJH) injection is a traditional Chinese medicine (TCM) injection and has a widely application in clinical practice. However, adverse drug reactions (ADRs) caused by YJH injection, majorly manifested as allergic reactions, have been reported. Hence, Effective and practical method for allergen screening and identification is needed. In this work, a LAD2/CMC model coupled online with HPLC-IT-TOF-MS system was developed to screen, analyze, and identify the allergenic components of YJH injection. A fraction was retained on the LAD2/CMC column, and identified as linarin (LN). Histamine release assay was performed by the multiple reaction monitoring (MRM) method of UPLC-ESI-MS/MS. Results showed that YJH injection and LN were in accord with their allergic effects by increasing histamine release. In conclusion, the LAD2/CMC-HPLC-IT-TOF-MS system developed in this study could be used to screen allergenic components in complex systems.

MRGPRX2 is essential for sinomenine hydrochloride induced anaphylactoid reactions

Graphical abstract Figure. No Caption available. ABSTRACT Mast cells are unique immunocytes that function as sentinel cells in host defense reactions such as immediate hypersensitivity responses and anaphylactic responses. The mast cell specific receptor MRGPRX2 (Mas‐related G protein‐coupled receptor X2) triggers mast cell degranulation—a key process in anaphylactic reactions. We sought to better understand anaphylactic reaction induced by sinomenine hydrochloride (SH). MRGPRX2‐related pseudo‐allergic reactions induced by SH were investigated using the hindpaw swelling and extravasation assay in vivo and mast cell degranulation assays in vitro. MrgprB2 knockout mice exhibit a reduced SH‐induced inflammation effect. Furthermore, MRGPRX2 (the orthologous gene of MrgprB2) related human mast cells are activated by SH in a dose‐dependent manner; however, MRGPRX2 knockdown mast cells showed reduced degranulation. The results showed a kind of mechanism that SH‐induced anaphylactoid reactions were mediated by MRGPRX2 via activating PLC molecular signaling pathways to provoke mast cells Ca2+ mobilization and degranulation.

Dual-mixed/CMC model for screening target components from traditional Chinese medicines simultaneously acting on EGFR & FGFR4 receptors

Radix Salviae Miltiorrhiae (also known as DanShen (DS) in China), a popular herbal drug in traditional Chinese medicine (TCM) for promoting blood circulation and treating blood stasis, has been reported to possess potential anti-tumor effects. The aim of the study was to develop an effective and practical method for screening and identifying bioactive compounds from Radix Salviae Miltiorrhiae. In this work, the epidermal growth factor receptor (EGFR) and fibroblast growth factor receptors 4 (FGFR4) dual-mixed/cell membrane chromatography (CMC) coupled with high performance liquid chromatography-electrospray ionization-ion trap-time of flight-multistage mass spectrum (HPLC-ESI-IT-TOF-MSn) was established and successfully used to identify the active components from Radix Salviae Miltiorrhiae. Salvianolic acid C (SAC), tanshinone I (Tan-I), tanshinone IIA (Tan-IIA), and cryptotanshinone (C-Tan) were identified as bioactive components with EGFR and FGFR4 activities. MTT and kinase assay were performed to investigate inhibitory effects of these compounds against EGFR and FGFR4 cells growth in vitro. Both cell viability and kinase activity showed that cryptotanshinone acting on EGFR receptor and tanshinone IIA acting on FGFR4 receptor. In conclusion, the EGFR & FGFR4 dual-mixed/CMC can simultaneously screen the bioactive components from TCMs that act on both EGFR and FGFR4 receptors, which significantly improve the efficiency of specific bioactive components identification from a complex system.

The anti-anaphylactoid effects of hydroxysafflor yellow A on the suppression of mast cell Ca2+ influx and degranulation

BACKGROUND Anaphylaxis is a type of potentially fatal hypersensitivity reaction resulting from the activation of mast cell mediators, especially histamine and lipid mediators. Non-IgE-mediated anaphylaxis can occur because of the direct activation of mast cells. Hydroxysafflor yellow A (HSYA) is the main chemical component of safflower (Carthamus tinctorius) and has been reported to have pharmacological activities. However, the anti-anaphylactoid effect of HSYA has not yet been investigated. PURPOSE The aims of this study were to evaluate the anti-anaphylactoid activity of HSYA in vivo and to investigate the underlying mechanism in vitro. METHODS The anti-anaphylactoid activity of HSYA was evaluated in a mouse model of hindpaw extravasation. Calcium imaging was used to assess intracellular Ca2+ mobilization. The levels of cytokines and chemokines released by stimulated mast cells were measured using enzyme immunoassay kits. Western blotting was used to explore the related molecular signaling pathways. RESULTS HSYA markedly inhibited mast cell degranulation by suppressing the activation of intracellular Ca2+ mobilization and preventing the release of cytokines and chemokines from mast cells in a dose-dependent manner via the PKC-PLCγ-IP3R signaling pathway. CONCLUSION In summary, HSYA has anti-anaphylactoid pharmacological activity, which makes it a potential candidate for the development of a novel agent to suppress drug-induced anaphylactoid reactions.

Screening of bioactive components from traditional Chinese medicines using cell membrane chromatography coupled with mass spectrometry

INTRODUCTION Cell membrane chromatography (CMC), as a highly selective type of affinity chromatography, has been demonstrated as an effective method to screen bioactive components acting on specific receptor from a complicated biological system. OBJECTIVE To review the recent research progress and the technical applications of these analytical methods using CMC combined with gas chromatography-mass spectrometry, (GC/MS) and liquid chromatography-mass spectrometry (LC/MS). METHODOLOGY In this review, we briefly introduce the CMC offline GC/MS, CMC online GC/MS, CMC offline LC/MS, and CMC online LC/MS system. And the practical application of these technologies is also enumerated. Then the future of these technologies and research methods were discussed. RESULTS Many bioactive components interacting with specific receptors have been screened and identified in traditional Chinese medicines. CONCLUSION CMC technique has been combined with GC/MS and HPLC/MS and these combined systems have been successfully used to screen bioactive components acting on specific receptors from a complicated biological system.