Identification of potential biomarkers for sepsis based on neutrophil extracellular trap-related genes.

Sepsis is a highly lethal disease that poses a serious threat to human health. Increasing evidence indicates that neutrophil extracellular traps (NETs) are key factors in the pathological progression of sepsis. This study aims to screen potential biomarkers for sepsis and delve into their regulatory function in the pathogenesis. We downloaded 6 microarray datasets from the Gene Expression Omnibus (GEO) database, with 4 as the training sets and 2 as the validation sets. NETs-related genes (NRGs) were obtained from relevant literature. Differential expression analysis was performed on four training sets separately. We intersected differentially expressed genes (DEGs) from the four training sets and NRGs, finally resulting in 19 NETs-related sepsis genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) unearthed that NETs-related sepsis genes were majorly abundant in functions and pathways such as defense response to bacterium and Neutrophil extracellular trap formation. Using the PPI network, the MCC algorithm, and the MCODE algorithm in the CytoHubba plugin, 7 sepsis hub genes (ELANE, TLR4, MPO, PADI4, CTSG, MMP9, S100A12) were identified. ROC curve for each Hub gene in the training and validation sets were plotted, which revealed that the Area Under Curve (AUC) values are all greater than 0.6, indicating good classification ability. A total of 349 miRNAs targeting Hub genes were predicted in the mirDIP database, and 620 lncRNAs targeting miRNAs were predicted in the ENCORI database. The ceRNA regulatory network was constructed using Cytoscape software. Finally, we employed the cMAP database to predict small molecular complexes as potentially effective drugs for the treatment of sepsis, such as chloroquine, harpagoside, and PD-123319. In conclusion, this project successfully identified 7 core genes, which may serve as promising candidates for novel sepsis biomarkers. Meanwhile, we constructed a related ceRNA network and predicted potential targeted drugs, providing potential therapeutic targets and treatment strategies for sepsis patients.

Insight into the Mechanism Underlying the Reduction of Digestibility and IgG/IgE Binding Ability in Ovalbumin during Different High-Temperature Conduction Modes-Induced Glycation.

Effects of different high-temperature conduction modes [high-temperature air conduction (HAC), high-temperature contact conduction (HCC), high-temperature steam conduction (HSC)]-induced glycation on the digestibility and IgG/IgE-binding ability of ovalbumin (OVA) were studied and the mechanisms were investigated. The conformation in OVA-HSC showed minimal structural changes based on circular dichroism, fluorescence, and ultraviolet spectroscopy. The degree of hydrolysis analysis indicated that glycated OVA was more resistant to digestive enzymes. Liquid chromatography-Orbitrap mass spectrometry identified 11, 14, and 15 glycation sites in OVA-HAC, OVA-HCC, and OVA-HSC, respectively. The IgG/IgE-binding ability of OVA was reduced during glycation and digestion, and the interactions among glycation, allergenicity, and digestibility were further investigated. Glycation sites masked the IgG/IgE epitopes resulting in a reduction in allergenicity. Digestion enzymes destroyed the IgG/IgE epitopes thus reducing allergenicity. Meanwhile, the glycation site in proximity to the digestion site of pepsin was observed to cause a reduction in digestibility.

Comparison of ovalbumin glycation induced by high-temperature steaming and high-temperature baking: A study combining conventional spectroscopy with high-resolution mass spectrometry.

High-temperature steaming (HTS) and high-temperature baking (HTB)-induced ovalbumin (OVA)-glucose glycation (140 °C, 1-3 min) were compared, and the different mechanisms were evaluated by changes in protein conformation, glycation sites and average degree of substitution per peptide molecule (DSP) values as well as the antioxidant activity of glycated OVA. Conventional spectroscopic results suggested that in comparison with HTB, HTS promoted protein expansion, increased ß-sheet content and made OVA structure more orderly. Liquid chromatography-high resolution mass spectrometry (LC-HRMS) analysis showed that 10 glycation sites were found under HTB, while 4 new glycation sites R111, R200, R219 and K323 appeared under HTS, and 2 of them (R219 and K323) were located in internal ß-sheet chains. The antioxidant activities of glycated OVA increased with increasing treatment time, and HTS showed stronger enhancement effect than HTB. Furthermore, the DSP values were generally higher under HTS than HTB. Compared with HTB, HTS with high penetrability could enhance the change of OVA primary structure and spatial conformation, making the protein structure more unfolded and stable, leading to more protein-sugar collisions occurred in inner OVA molecular and significantly promoted glycation. In conclusion, HTS is a promising method for high-temperature short-time glycation reaction, with drastically increasing the protein antioxidant activities.

Effects of different high-temperature conduction modes on the ovalbumin-glucose model: AGEs production and regulation of glycated ovalbumin on gut microbiota.

Food high-temperature processing frequently induces the production of advanced glycation end products (AGEs) in the food industry. In this study, the effects of three high-temperature conduction modes on the AGEs production derived from ovalbumin (OVA)-glucose model and the regulation of glycated OVA on gut microbiota were investigated. The peak time of OVA shifted maximally from 13.72 to 13.57 due to the rise in molecular weight, confirming successful coupling between OVA and glucose. The inhibition of superheated steam (SS) on AGEs was observed, with the sample treated by SS showing the lowest content among glycated OVA groups. The analysis revealed an increase in AGEs during digestion and a decrease in fermentation, suggesting the release during digestion and the availability by intestinal flora. Furthermore, an expansion of Bifidobacterium and Lactobacillus, and the inhibition of Desulfovibrio and Escherichia-Shigella were observed, indicating the prebiotic activity of glycated OVA and its potential to improve intestinal health. These results provide valuable information for controlling high-temperature processing to inhibit AGEs formation and highlight the positive effects of glycated proteins on intestinal health.

Extraction optimization and identification of four advanced glycation-end products inhibitors from lotus leaves and interaction mechanism analysis.

Previous research indicated lotus leaves extract could effectively inhibit advanced glycation end-products (AGEs) formation, but the optimal extraction condition, bio-active compounds and interaction mechanism remain unclear. The current study was designed to optimize the extraction parameters of AGEs inhibitors from lotus leaves by bio-activity-guided approach. The bio-active compounds were enriched and identified, the interaction mechanisms of inhibitors with ovalbumin (OVA) were investigated by fluorescence spectroscopy and molecular docking. The optimum extraction parameters were solid-liquid ratio of 1:30, ethanol concentration of 70 %, ultrasonic time of 40 min, temperature of 50 °C, and power of 400 W. Isoquercitrin, hyperoside, astragalin, and trifolin were identified from the 80 % ethanol fraction of lotus leaves (80HY). Hyperoside and isoquercitrin were dominant AGEs inhibitors and accounted for 55.97 % of 80HY. Isoquercitrin, hyperoside, trifolin interacted with OVA via the same mechanism, hyperoside exhibited the strongest affinity, trifolin caused the most conformational changes.

Traceability and identification of fish gelatin from seven cyprinid fishes by high performance liquid chromatography and high-resolution mass spectrometry.

The broad application prospect of fish gelatin makes the traceability and identification of fish gelatin imminent. High performance liquid chromatography and high-resolution mass spectrometry (HPLC-MS/MS) was used to identify fish gelatins in seven commercial cyprinid fishes, namely, black carp, grass carp, silver carp, bighead carp, common carp, crucian carp, and Wuchang bream. By comparison with theoretical mammalian collagen (bovine and porcine collagen), the common and unique theoretical peptides were found in the collagen of grass carp, silver carp, and crucian carp, respectively. HPLC-MS/MS results showed that 7 common characteristic peptides were obtained from seven cyprinid fish gelatins. Moreover, 44, 36, and 42 unique characteristic peptides were detected in the gelatins of grass carp, silver carp, and crucian carp, respectively. The combined use of common and unique characteristic peptides could improve the accuracy and authenticity of traceability and identification of fish gelatin in comparison with mammalian gelatin.

Inhibitory activity and mechanism of guavinoside B from guava fruits against α-glucosidase: Insights by spectroscopy and molecular docking analyses.

Guavinoside B (GUB) is the main active substance in guava fruit and shows promising biological activities. In this study, the inhibitory activity and mechanism of GUB on α-glucosidase were studied by using spectroscopic techniques, kinetic analysis, and molecular docking. Results indicated that GUB possessed significant inhibition ability on α-glucosidase, which was about 10 times that of acarbose. The GUB was a mixed-type inhibitor, which suppressed the activity of α-glucosidase through a reversible process. Fluorescence analysis revealed that GUB quenched the fluorescence of α-glucosidase statically, the formation of GUB-α-glucosidase complex was a spontaneous and exothermic process, van der Waals forces, hydrogen bonding, and hydrophobic interaction were the predominant driving forces, only one single-binding site on α-glucosidase was involved in the binding process. GUB inserted into the hydrophobic pocket of α-glucosidase with 11 hydrogen bonds and two π-π stacking formed. The presence of GUB changed the microenvironment near the fluorescent amino acids of α-glucosidase, and the structure of α-glucosidase was slightly changed, eventually leading to the decrease of α-glucosidase activity. PRACTICAL APPLICATIONS: Diabetes mellitus (DM) is a worldwide chronic metabolic disease threatening human health seriously. Guava fruit is a popular fruit, and its extracts were reported to show many biological activities. GUB is the main benzophenone glycoside in guava fruits. However, the inhibitory activity and mechanism of its specific active compound GUB are still unclear. Studies have shown that GUB could reversibly inhibit the activity of α-glucosidase, and its inhibitory ability was about 10 times that of acarbose. The kinetics and mechanism of inhibition were revealed. These will facilitate the further research and application of guava fruit and GUB in functional and healthy foods against hyperglycinaemia or even DM.

Enhanced IL-10 inhibits proliferation and promotes apoptosis of HUVECs through STAT3 signaling pathway in sepsis.

AIMS: The present study aims to determine the expression of interleukin (IL)-10 in peripheral blood of patients with sepsis, and investigate its effects on the biological function of vascular endothelial cells. METHODS: Thirty-six sepsis patients and 20 healthy subjects were included. Peripheral blood was collected from all subjects. ELISA was used to determine IL-10 content in serum. A ratio of IL-10⁺ T cells was determined by flow cytometry. CCK-8 assay was used to investigate proliferation. Cell cycle and apoptosis were analyzed by flow cytometry. Western blotting was used to examine the expression of phosphorylated STAT3 protein. RESULTS: The content of IL-10 and the ratio of IL-10⁺ T cells were enhanced in pa-tients with sepsis. Serum from patients with sepsis inhibited the proliferation of HU-VECs, and addition of IL-10 antibody reversed this effect. IL-10 in the serum from patients with sepsis promoted the apoptosis of HUVECs. IL-10 inhibited the proliferation and promoted the apoptosis of HUVECs by enhancing the phosphorylation of STAT3. CONCLUSIONS: The present study demonstrates that the content of IL-10 and the ratio of IL-10⁺ T cells in peripheral blood of patients with sepsis are up-regulated, and this inhibits HUVEC proliferation and promotes HUVEC apoptosis through STAT3 sig-naling pathway. The results in this study provide a new experimental basis for further understanding the molecular mechanism of sepsis-induced vascular injury.

Vascular Endothelial Cells Activate Peripheral Natural Killer T Cells and Participate in Regulation of Downstream Immune Cascades in Patients with Sepsis.

BACKGROUND This study investigated the effect of supernatant of endothelial cells stimulated by peripheral blood serum from sepsis patients on phenotype and function of peripheral NKT cells. MATERIAL AND METHODS Twenty-one patients with sepsis and 21 healthy subjects were included. Peripheral blood (5 ml) was collected from all patients and healthy subjects. To isolate peripheral blood mononuclear cells (PBMCs), Ficoll lymphocyte separation solution was used. Flow cytometry was carried out to determine NKT cell ratio, activity, and cytokine secretion. Human umbilical vein endothelial cells were cultured with serum from sepsis patients for 48 h before changing to fresh medium, and supernatant was collected. The supernatant was used to co-culture PBMCs before analyzing NKT activity and cytokines. RESULTS The ratios of CD3-CD56+NK cells and CD3+CD56+NKT cells were increased in peripheral blood from sepsis patients. Surface receptors p30, G2D, and p44 of CD3+CD56+NKT cells were elevated, while inhibitory receptors NKG2A and 158b were decreased. CD4+ NKT cells in peripheral blood from sepsis patients were enhanced. GranB, IFN-γ, IL-4, and IL-17 in NKT cells from sepsis patients were up-regulated. After co-culture with vascular endothelial cells treated with sepsis serum, expression of p30 and G2D in NKT cells was upregulated, and number of TCRVa24-positive cells was increased. In addition, ratio of CD4+NKT cells was increased, and intracellular expression of IL-4 and IFN-γ was elevated. CONCLUSIONS The study demonstrates that the level of NKT cells in peripheral blood from sepsis patients is increased, and their activity is enhanced. In addition, vascular endothelial cells from sepsis patients can regulate the activity of NKT cells.