Shuxuening injection, derived from Ginkgo biloba leaf, induced pseudo-allergic reactions through hyperactivation of mTOR

Research of saccharides and related biocomplexes: A review with recent techniques and applications

Saccharides and biocompounds as saccharide (sugar) complexes have various roles and biological functions in living organisms due to modifications via nucleophilic substitution, polymerization, and complex formation reactions. Mostly, mono-, di-, oligo-, and polysaccharides are stabilized to inactive glycosides, which are formed in metabolic pathways. Natural saccharides are important in food and environmental monitoring. Glycosides with various functionalities are significant in clinical and medical research. Saccharides are often studied with the chromatographic methods of hydrophilic interaction liquid chromatography and anion exchange chromatograpy, but also with capillary electrophoresis and mass spectrometry with their on-line coupling systems. Sample preparation is important in the identification of saccharide compounds. The cases discussed here focus on bioscience, clinical, and food applications.

A novel method for evaluating pseudoallergy based on β-hexosaminidase and its application for traditional Chinese medicine injections

Pseudoallergy is a typical and common adverse drug reaction to injections, especially in traditional Chinese medicine injections (TCMIs). At present, the evaluation methods for pseudoallergy include cell methods in vitro and animal methods in vivo. The mast cell evaluation method based on the β-hexosaminidase (β-Hex)-catalyzed substrate, 4-nitrophenyl-β-N-acetyl-D-glucosaminide (4-NPG), is an important method for the evaluation of drug-induced pseudoallergy, but it is prone to false positive results and has insufficient sensitivity. In this study, a novel β-Hex evaluation system with rat basophilic leukemia-2H3 cells based on high-performance liquid chromatography-fluorescence detection (HPLC-FLD) was established, which effectively increased the sensitivity and avoided false positive results. Cell viabilities were measured by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide assay. In addition, a method for the determination of histamine, which is another indicator in the development of pseudoallergy, was established to validate the above method. The results of this novel method indicated that two TCMIs (Shuxuening injection and Shenqi Fuzheng injection), which were considered to be pseudoallergenic using 4-NPG, were not pseudoallergenic. Overall, the novel β-Hex/HPLC-FLD evaluation system using Rat basophilic leukemia-2H3 cells established was effective and precise. It could be used for the evaluation of pseudoallergic reactions caused by TCMIs and other injections.

Pseudo-allergic reactions induced by Chinese medicine injections: a review

Traditional Chinese medicine injections (TCMIs) is a new dosage form of Chinese medicine, which plays a unique role in rescuing patients with critical illnesses that are difficult to replace. With the rapid development and widespread application of TCMIs in recent years, their adverse events have emerged and attracted much attention. Among them, pseudo-allergic reactions, i.e., the most significant adverse reactions occurring with the first dose without immunoglobulin E mediated conditions. Currently, studies on the types of TCMIs and antibiotic mechanisms that cause pseudo-allergic reactions are incomplete, and standard models and technical guidelines for assessing TCMIs have not been established. First, this review describes the causes of pseudo-allergic reactions, in which the components and structures responsible for pseudo-allergic reactions are summarized. Second, the mechanisms by which pseudo-allergic reactions are discussed, including direct stimulation of mast cells and complement activation. Then, research models of pseudo-allergic reaction diseases are reviewed, including animal models and cellular models. Finally, the outlook and future challenges for the development of pseudo-allergic reactions in traditional Chinese medicine (TCM) are outlined. This shed new light on the assessment and risk prevention of pseudo-allergic reactions in TCM and the prevention of clinical adverse reactions in TCM.

MrgprX2 regulates mast cell degranulation through PI3K/AKT and PLCγ signaling in pseudo-allergic reactions

The G protein-coupled receptor MrgprX2 in mast cells is known to be a crucial receptor for pseudo-allergic reactions. MrgprX2 activation leads to elevated intracellular calcium levels and mast cell degranulation, but the underlying mechanism remains to be elucidated. Herein, we investigated the role of the phosphatidylinositol 3 kinase (PI3K)/serum-threonine kinase (AKT) signaling pathway and phospholipase C gamma (PLCγ) in mast cell degranulation mediated by MrgprX2 in LAD2 human-derived mast cells. The results showed that phosphorylated AKT (p-AKT) and PLCγ up-regulation were accompanied by an increase in intracellular calcium following activation of MrgprX2 by Compound 48/80, an inducer of mast cell degranulation. In contrast, p-AKT and PLCγ were down-regulated and intracellular calcium levels decreased after MrgprX2 knockdown. Mast cell degranulation was clearly suppressed; however, inhibiting PI3K and PLCγ phosphorylation did not influence MrgprX2 expression. The increase in calcium concentration was suppressed and mast cell degranulation was weakened. Furthermore, by inhibiting PI3K and PLCγ phosphorylation in animals, the allergic symptoms caused by C48/80 were obviously reduced. We deduced that during the mast cell degranulation observed in pseudoallergic reactions, MrgprX2 regulated intracellular calcium levels via the PI3K/AKT and PLCγ pathways.