Distribution and transfer rules of polycyclic aromatic hydrocarbons in soil-wheat ecosystems in China.

The translocation and accumulation patterns of polycyclic aromatic hydrocarbons (PAHs) in the soil-crop system have important implications for the fate of PAHs and human health. This study summarized the concentrations of 16 priority PAHs in the soils and various parts of mature winter wheat in China, sourced from a screening of previous literature in English and Chinese databases. The study analyzes the distribution characteristics, transfer patterns, and human health risks of PAHs in sites studied in Shaanxi, Henan, and Shandong provinces. The results showed that the concentrations of Σ16 PAHs in the rhizosphere soil of wheat ranged from 10.30 to 893.68 ng/g, in descending order of Shaanxi > Henan > average > Shandong. In sites with mild to moderate contamination (200 < Σ16 PAHs < 600 ng/g; i.e., Henan and Shaanxi), the concentration of Σ16 PAHs in the roots was higher than that in the stems or the grains, while in contamination-free sites (Σ16 PAHs < 200 ng/g; i.e., Shandong), the highest concentration of Σ16 PAHs was found in the stems. Generally, the concentrations of PAHs increased in the order of roots-stems-grains. The predominant PAHs in each part of wheat were 2- or 3-ring compounds, with five- or six-ring PAHs being more prevalent in wheat from Shanghe, Shandong. The bioaccumulation factors of different wheat parts from Shaanxi and Henan were consistently smaller than 1, and low- and medium-ring (2-4 rings) PAHs had bigger bioconcentration factors than high-ring (5-6 rings) PAHs. However, the accumulation of PAHs in the aboveground parts of wheat was larger than that in the underground parts of the Shandong sites. The linear regression relationship between the octanol-water partition coefficient and root concentration factor (RCF) of PAHs reflected that low and medium-ring PAHs were more easily absorbed by wheat roots than high-ring PAHs in Shaanxi and Henan. Our assessment of the health risks of oral wheat intake in adults and children by the incremental lifetime cancer risk (ILCR) model found a potential carcinogenic risk for both age groups in each province, with higher risks in adults than in children.

Integrating Widely Targeted Lipidomics and Transcriptomics Unravels Aberrant Lipid Metabolism and Identifies Potential Biomarkers of Food Allergies in Rats.

SCOPE: Oral food challenges (OFCs) are currently the gold standard for determining the clinical reactivity of food allergy (FA) but are time-consuming, expensive, and risky. To screen novel peripheral biomarkers of FA and characterize the aberrant lipid metabolism in serum, 24 rats are divided into four groups: peanut, milk, and shrimp allergy (PA, MA, and SA, respectively) and control groups, with six rats in each group, and used for widely targeted lipidomics and transcriptomics analysis. METHODS AND RESULTS: Widely targeted lipidomics reveal 144, 162, and 206 differentially accumulated lipids in PA, MA, and SA groups, respectively. The study integrates widely targeted lipidomics and transcriptomics and identifies abnormal lipid metabolism correlated with widespread differential accumulation of diverse lipids (including triacylglycerol, diacylglycerol, sphingolipid, and glycerophospholipid) in PA, MA, and SA. Simplified random forest classifier is constructed through five repetitions of 10-fold cross-validation to distinguish allergy from control. A subset of 15 lipids as potential biomarkers allows for more reliable and more accurate prediction of FA. Independent replication validates the reproducibility of potential biomarkers. CONCLUSION: The results reveal the major abnormalities in lipid metabolism and suggest the potential role of lipids as novel molecular signatures for FA.

Extracellular Ca2+ aggravates IgE-induced allergic reaction in mast cells through GPRC6A, a novel family C G-protein-coupled receptor.

AIMS: As an essential indicator of allergic reactions, mast cell (MC) activation involves FcεRI-mediated signaling and the release of allergic mediators. In FcεRI signaling, Ca2+ is located at the intersection of multiple cellular signaling pathways. However, the effect of extracellular Ca2+ (exCa2+) on MCs during anaphylaxis remains unclear, along with its exact mechanisms. Therefore, we sought to determine whether and how elevated exCa2+ amplifies allergic reactions. MAIN METHODS: In vitro experiments used immunoglobulin E (IgE)/antigen (Ag)-induced activation of rat and mouse MCs in vitro. The levels of MC degranulation mediators were used to evaluate the effect of exCa2+. In vivo experiments used MC-mediated passive systemic anaphylaxis (PCA) Balb/c mice. After stimulation, anaphylaxis indexes such as rectal temperature and allergic symptom score were detected. KEY FINDINGS: In vitro experiments revealed that exCa2+ is a stimulus signal for the aggravation of allergic reactions in MCs. When antagonists or siRNA inhibited GPRC6, MCs released fewer inflammatory mediators. Moreover, in vivo experiments confirmed in vitro results. Allergic symptoms were alleviated by antagonists NPS2143 in PCA mice, demonstrating that exCa2+ aggravates allergic reactions through GPRC6A. SIGNIFICANCE: Our study provides an essential theoretical basis for targeting Ca2+ and GPRC6A as therapeutic options for allergies.

Lentinan Inhibited the Activation of Th2 Cells in Allergic Mice by Reducing the Amplitude of Changes in Biological Rhythm.

INTRODUCTION: Biological rhythm is inextricably linked to the physiological mechanisms of allergic diseases, but the exact mechanisms are still poorly understood. Clinical studies have reported rhythmic fluctuations in allergic diseases. The search for natural and harmless active ingredients based on biological rhythm with which to regulate allergic diseases is essential for the control of food allergy. METHODS: In this study, mice were treated at different time points to determine the link between the severity of allergic reactions and the circadian clock genes. The mice were treated with lentinan, either continuously or discontinuously, to assess their clinical symptoms, vascular permeability, immune cells, cytokines, and clock genes. Specifically, rat basophilic leukemia (RBL-2H3) cells were treated with lentinan and the rhythmic changes of cell degranulation were measured. RESULTS: The results in different models showed that the allergic reactions in mice treated at different time points were significantly different and thus related to fluctuations in biological rhythm. Treatment with lentinan was found to reduce the amplitude of changes in the clock genes, such as the activation of Per and Cry proteins in allergic mice, as well as to regulate biological rhythm in cells, inhibit the activation of Th2 cells, and alleviate allergic reactions. Furthermore, lentinan changed the rhythm of degranulation in RBL-2H3 cells. CONCLUSION: Lentinan was, therefore, determined to successfully alleviate allergic reactions by reducing the amplitude of changes in the body's biological rhythm, inhibiting the activation of Th2 cells, and affecting the immune microenvironment.

Cloning, expression, and characterization of an enzyme possessing both glutaredoxin and dehydroascorbate reductase activity from Taiwanofungus camphorata.

Glutaredoxins (Grxs) play important roles in the reduction of disulfides via reduced glutathione as a reductant. A cDNA (503 bp, EU193660) encoding a putative Grx was cloned from Taiwanofugus camphorata (Tc). The deduced amino acid sequence is conserved among the reported dithiol Grxs. A 3D homology structure was created for this TcGrx. To characterize the TcGrx enzyme, the coding region was subcloned into an expression vector pET-20b(+) and transformed into Escherichia coli . Functional TcGrx was expressed and purified by Ni(2+)-nitrilotriacetic acid Sepharose. The purified enzyme showed bands of approximately 15 kDa on 15% sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The TcGrx encodes a protein possessing both Grx and dehydroascorbate reductase (DHAR) activity. The Michaelis constant (K(m)) values for beta-hydroxyethyl disulfide (HED) and dehydroascorbate (DHA) were 0.57 and 1.85 mM, respectively. The half-life of deactivation of the protein at 100 degrees C was 8.5 min, and its thermal inactivation rate constant K(d) was 6.52 x 10(-2) min(-1). The enzyme was active under a broad pH range from 6.0 to 10.0 and in the presence of imidazole up to 0.4 M. The enzyme was susceptible to SDS denaturation and protease degradation/inactivation.

Dehydroascorbate reductase cDNA from sweet potato (Ipomoea batatas [L.] Lam): expression, enzyme properties, and kinetic studies.

A cDNA encoding a putative dehydroascorbate reductase (DHAR) was cloned from sweet potato. The deduced protein showed a high level of sequence homology with DHARs from other plants (67 to approximately 81%). Functional sweet potato DHAR was overexpressed and purified. The purified enzyme showed an active monomeric form on a 12% native PAGE. The protein's half-life of deactivation at 50 degrees C was 10.1 min, and its thermal inactivation rate constant K(d) was 6.4 x 10(-2) min(-1). The enzyme was stable in a broad pH range from 6.0-11.0 and in the presence of 0.8 M imidazole. The K(m) values for DHA and GSH were 0.19 and 2.38 mM, respectively.