內(nèi)容: This study mainly investigated the regulatory effect of Rosa roxburghii Tratt fruit juice fermented by Lacticaseibacillus paracasei SR10-1 (LAB-RRTJ) on modulating gut microbiota in dextran sulfate sodium (DSS)-induced ulcerative colitis in mice. Compared to control group, DSS induction decreased body weight of mice, indexes of Shannon, Simpson, Chao1 and Faith_pd, and increased disease activity index (DAI) and levels of interleukin 1β (IL-1β), IL-6, tumor necrosis factor α (TNF-α) and interferon-γ (IFN-γ); And this induction also led to an increase in Proteobacteria, Verrucomicrobia and Actinobacteria at phylum level, harmful bacterial species richness at genus level, and relative richness of S. sciuri, Desulfovibrio C21_c20, R. gnavus and Akkermansia muciniphila at species level, and a decrease in Firmicutes at phylum level and relative richness of B. acidifaciens in mice. LAB-RRTJ increased body weight of mice with DSS induced ulcerative colitis (UC) and indexes of Shannon, Simpson, Chao1 and Faith_pd, reduced DAI and the content of four inflammatory factors and improved gut microbiota imbalance in DSS induced UC mice. Besides, the number of operational taxonomic units (OTUs) increased, α-diversity and β-diversity were restored and similar to those in mice in the control group after LAB-RRTJ treatment. Compared with the positive drug treatment group, LAB-RRTJ has a better effect on regulating gut microbiota diversity in colitis mice. Correlation analysis showed that inflammatory factors were positively correlated with harmful bacteria and negatively correlated with beneficial bacteria which commonly found in some colitis mice. Taken together, our study demonstrated that LAB-RRTJ could alleviate DSS-induced colitis in mice through the modulation of inflammatory cytokines and gut microbiota composition.

內(nèi)容: Low molecular weight polysaccharides can be isolated from Sargassum thunbergii (LMPST) and in vitro experiments were conducted to evaluate the inhibitory effects on lipids. Two natures of LMPST were attained from S. thunbergii and appraised their LMPST on palmitic acid (PA) induced lipid accretion in HepG2, and 3T3-L1 cells. LMPST treatment lessened lipid deposition and intracellular free fatty acid and triglyceride intensities in PA-treated above mentioned cells. The mechanistic study publicized that LMPST2 significantly suppressed adipogenesis and stimulated the PA-treated 3T3-L1 cells occupied in the lipolysis pathway. Furthermore, in PA-treated HepG2 cells, the free fatty acid oxidation was significantly increased by LMPST2. Given these constructive properties of LMPST2 from S. thunbergii, is a potential candidate for diminishing the intracellular lipids, and for a therapeutic agent in those conditions.

內(nèi)容: Here, we aimed to study the changes in proteome of golden pompano fillets during post-mortem storage. Tandem mass tags (TMT) -labeled quantitative proteomic strategy was applied to investigate the relationships between protein changes and quality characteristics of modified atmosphere packaging (MAP) fillets during superchilling (-3 °C) storage. Scanning electron microscopy was used to show that the muscle histology microstructure of fillets was damaged to varying degrees, and low-field nuclear magnetic resonance was used to find that the immobilized water and free water in the muscle of fillets changed significantly. Total sulfhydryl content, TCA-soluble peptides and Ca2+-ATPase activity also showed that the fillet protein had a deterioration by oxidation and denaturation. The Fresh (FS), MAP, and air packaging (AP) groups were set. Total of 150 proteins were identified as differential abundant proteins (DAPs) in MAP/FS, while 209 DAPs were in AP/FS group. The KEGG pathway analysis indicated that most DAPs were involved in binding proteins and protein turnover. Correlation analysis found that 52 DAPs were correlated with quality traits. Among them, 8 highly correlated DAPs are expected to be used as potential quality markers for protein oxidation and water-holding capacity. These results provide a further understanding of the muscle deterioration mechanism of packaging golden pompano fillets during superchilling.

內(nèi)容: Ulcerative colitis (UC) is a common inflammatory disease of the gastrointestinal tract. Traditional Chinese medicine (TCM) has long been used in Asia as a treatment for UC and Puerariae Radix (PR) is a reliable anti-diarrheal therapy. The aims of this study were to investigate the protective effect of PR using the dextran sulfate sodium salt (DSS)-induced UC model in mice and identify molecular mechanisms of PR action. The chemical constituents of PR via ultra-performance liquid chromatography/tandem mass spectrometry and identified potential PR and UC targets using a network pharmacology (NP) approach were obtained to guide mouse experiments. A total of 180 peaks were identified from PR including 48 flavonoids, 46 organic acids, 14 amino acids, 8 phenols, 8 carbohydrates, 7 alkaloids, 6 coumarins and 43 other constituents. NP results showed that caspase-1 was the most dysregulated of the core genes associated with UC. A PR dose of 0.136 mg/g administered to DSS treated mice reversed weight loss and decreased colon lengths found in UC mice. PR also alleviated intestinal mucosal shedding, inflammatory cell infiltration and mucin loss. PR treatment suppressed upregulation of NOD-like receptor protein 3 (NLRP3), cysteinyl aspartate-specific proteases-1 (caspase-1), apoptosis-associated speck-like (ASC) and gasdermin D (GSDMD) at both the protein and mRNA expression levels. The addition of a small molecule dual-specificity phosphatase inhibitor NSC 95397 inhibited the positive effects of PR. These results indicated that PR exerts a protective effect on DSS-induced colitis by inhibiting NLRP3 inflammasome activation in mice.

內(nèi)容: The taste presentation and receptor perception mechanism of the salty peptide of Stropharia rugosoannulata were predicted and verified using peptide omics and molecular interaction techniques. The combination of aspartic acid (D) and glutamic acid (E), or peptide fragments composed of arginine (R), constitute the characteristic taste structural basis of salty peptides of S. rugosoannulata. The taste intensity of the salty peptide positively correlates with its concentration within a specific concentration range (0.25–1.0 mg/mL). The receptor more easily recognizes the first amino acid residue at the N-terminal of salty peptides and the aspartic acid residue in the peptides. GLU513, ASP707, and VAL508 are the critical amino acid residues for the receptor to recognize salty peptides. TRPV1 is specifically the receptor for recognizing salty peptides. Hydrogen bonds and electrostatic interactions are the main driving forces for the interactions between salty peptides and TRPV1 receptors. KSWDDFFTR has the most potent binding capacity with the receptor and has tremendous potential for application in sodium salt substitution. This study confirmed the taste receptor that specifically recognizes salty peptides, analyzed the receptor-peptide binding interaction, and provided a new idea for understanding the taste receptor perception of salty peptides.

內(nèi)容: Aflatoxin B1 (AFB1) is a naturally-occurring mycotoxin and recognized as the most toxic foodborne toxin, particularly causing damages to kidney. Glomerular podocytes are terminally differentiated epithelial cells. AFB1 induces podocyte inflammation, proteinuria and renal dysfunction. Studying the mechanism of AFB1-induced podocyte inflammation and murine kidney dysfunction, we detected that AFB1 increased ubiquitin-dependent degradation of the transcription factor RelA through enhanced interaction of RelA with E3 ubiquitin ligase tripartite motif containing 7 (TRIM7) in mouse podocyte clone-5 (MPC-5) and mouse glomeruli. Reduction of RelA resulted in decreasing microRNA-9 (miR-9) and activating the chemokine receptor 4 (CXCR4), thioredoxin interacting protein (TXNIP), and NOD-like receptor pyrin domain-containing 3 (NLRP3) signaling axis (CXCR4/TXNIP/NLRP3 pathway), leading to podocyte inflammation. We also determined that downregulation of miR-9 led to CXCR4 expression and the downstream TXNIP/NLRP3 pathway activation. Overexpression of miR-9 or deletion of CXCR4 suppressed AFB1-induced CXCR4/TXNIP/NLRP3 pathway, resulting in alleviating podocyte inflammation and kidney dysfunction. Our findings indicated that ubiquitin-dependent proteolysis of RelA, downregulation of miR-9, and activation of CXCR4/TXNIP/NLRP3 pathway played an essential role in AFB1-induced glomerular podocyte inflammation. Our study revealed a novel mechanism, via RelA, for the control of AFB1’s nephrotoxicity, leading to an effective protection of food safety and public health.

內(nèi)容: Alpha-lactalbumin (α-LA) is a major whey protein found in breast milk and plays a crucial role in the growth and development of infants. In this study, Bacillus subtilis RIK1285 harboring AprE signal peptide (SP) was selected as the original strain for the production of α-LA. It was found that α-LA was identified in the pellet after ultrasonic disruption and centrifugation instead of in the fermentation supernatant. The original strain most likely only produced α-LA intracellular, but not extracellular. To improve the expression and secretion of α-LA in RIK1285, a library of 173 homologous SPs from the B. subtilis 168 genome was fused with target LALBA gene in the pBE-S vector and expressed extracellularly in RIK1285. SP YjcN was determined to be the best signal peptide. Bands in supernatant were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and purified by nickel column to calculate the highest yield signal peptide. In addition, different promoters (PaprE, P43, and Pglv) were compared and applied. The results indicated that the strain RIK1285-pBE-Pglv-YjcN-LALBA had the highest α-LA yield, reaching 122.04 μg/mL. This study demonstrates successful expression and secretion of human α-LA in B. subtilis and establishes a foundation for simulating breast milk for infant formulas and developing bioengineered milk.

內(nèi)容: Free amino acid (FAA) is the important component of vinegar that influences quality perception and consumer acceptance. FAA is one of the major metabolites produced by microorganisms; however, the microbial metabolic network on FAA biosynthesis remains unclear. Through metagenomic analysis, this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation. Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways. The metabolic network for FAA biosynthesis was then constructed, and the microbial distribution in different metabolic pathways was illuminated. The results revealed that 5 functional genera were closely involved in FAA biosynthesis. This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation.

內(nèi)容: Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or immunotherapy. However, it is still uncertain how to select immunotherapy drugs to combine with intermittent fasting. Herein we observed that two cycles of fasting treatment significantly inhibited breast tumor growth and lung tissue metastasis, as well as prolonged overall survival in mice bearing 4T1 and 4T07 breast cancer. During this process, both the immunosuppressive monocytic- (M-) and granulocytic- (G-) myeloid-derived suppressor cell (MDSC) decreased, accompanied by an increase in interleukin (IL) 7R+ and granzyme B+ T cells in the tumor microenvironment. Interestingly, we observed that Ly6Glow G-MDSC sharply decreased after fasting treatment, and the cell surface markers and protein mass spectrometry data showed potential therapeutic targets. Mechanistic investigation revealed that glucose metabolism restriction suppressed the splenic granulocyte-monocyte progenitor and the generation of colony-stimulating factors and IL-6, which both contributed to the accumulation of G-MDSC. On the other hand, glucose metabolism restriction can directly induce the apoptosis of Ly6Glow G-MDSC, but not Ly6Ghigh subsets. In summary, these results suggest that glucose metabolism restriction induced by fasting treatment attenuates the immune-suppressive milieu and enhances the activation of CD3+ T cells, providing potential solutions for enhancing immune-based cancer interventions.

內(nèi)容: Food allergy is a significant public health concern globally. Certain probiotics have been found to enhance food allergy by regulating immune-microbe interactions in animal models and patients. However, the effects of Bifidobacterium lactis Probio-M8 on food allergy have not been thoroughly investigated. The present study examined the anti-allergic properties of Probio-M8, particularly in relation to immune response and gut microbiota composition. Results demonstrate that oral administration of Probio-M8 effectively mitigated the allergy symptoms triggered by ovalbumin (OVA) by ameliorating the morphological damage in the jejunum, reducing OVA-specific IgE and histamine levels in the serum, and suppressing Th2 cytokines (interleukin (IL) 4 and IL-13) while increasing Th1 cytokines (interferon (IFN) γ) and regulatory T (Treg) cytokines (IL-10 and transforming growth factor (TGF) β1) in the culture supernatants of splenic cells. Furthermore, Probio-M8 effectively altered the diversity and composition of gut microbiota, particularly the relative abundances of Akkermansia_muciniphila in OVA-induced mice. Compared to the OVA group, the Probio-M8 group showed a decrease in the relative abundance of Akkermansia_muciniphila. In conclusion, Probio-M8 demonstrates the potential to alleviate food allergy by regulating the Th1/Th2 response and modulating gut microbiota, thereby offering a novel therapeutic strategy for patients with food allergy.