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Diet rich in chicken protein has gained a widespread popularity for its profound effect on weight loss and glycemic control; however, its long-term effect on cardiovascular health and the underlying mechanisms remains obscure. Here, we demonstrated that higher intake of chicken protein was an independent risk factor for sub-clinical atherosclerosis. Adherence to high chicken protein diet (HCD) alleviated excessive weight gain and glycemic control regardless of the presence of gut microbiota in apolipoprotein E-deficient mice. In contrast, long-term HCD administration enhanced intestinal cholesterol absorption and accelerated atherosclerotic plaque formation in a gut microbiota-dependent manner. Integrative analysis of 16S rDNA sequencing and metabolomics profiling identified 3-Methyl-L-histidine (3-MH), resulting from an enrichment of , as the key microbial effector to the atherogenic effect of HCD. Mechanistically, 3-MH facilitated the binding of hepatocyte nuclear factor 1A (HNF1A) to the promoter of NPC1-like intracellular cholesterol transporter 1 (NPC1L1), whereas inhibition of HNF1A-NPC1L1 axis abolished the atherogenic effect of 3-MH. Our findings uncovered a novel link between microbiota-derived 3-MH and disturbed cholesterol homeostasis, which ultimately accelerated atherosclerosis, and argued against the recommendation of HCD as weight loss regimens considering its adverse role in vascular health.
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Molecular interactions, structural effects, and binding affinities between silver ions (Ag) and amyloid beta (Aβ) peptides.
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- Author: Lakela AL  |  Berntsson E  |  Vosough F  |  Jarvet J  |  Paul S  |  Barth A  |  Gräslund A  |  Roos PM  |  Wärmländer SKTS  | 
Because silver is toxic to microbes, but not considered toxic to humans, the metal has been used as an antimicrobial agent since ancient times. Today, silver nanoparticles and colloidal silver are used for antibacterial purposes, and silver-peptide and similar complexes are being developed as therapeutic agents. Yet, the health effects of silver exposure are not fully understood, nor are the molecular details of silver-protein interactions. In Alzheimer's disease, the most common form of dementia worldwide, amyloid-β (Aβ) peptides aggregate to form soluble oligomers that are neurotoxic. Here, we report that monovalent silver ions (Ag) bind wildtype Aβ peptides with a binding affinity of 25 ± 12 µM in MES buffer at 20 °C. Similar binding affinities are observed for wt Aβ peptides bound to SDS micelles, for an Aβ(H6A) mutant, and for a truncated Aβ(4-40) variant containing an ATCUN (Amino Terminal Cu and Ni) motif. Weaker Ag binding is observed for the wt Aβ peptide at acidic pH, and for an Aβ mutant without histidines. These results are compatible with Ag ions binding to the N-terminal segment of Aβ peptides with linear bis-his coordination. Because the Ag ions do not induce any changes in the size or structure of Aβ oligomers, we suggest that Ag ions have a minor influence on Aβ toxicity.
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Facile Antibody Immobilization on a Redox-Active Thionine-Functionalized Carbon Nanofiber Surface for Rapid Electrochemical Immunosensing of a Bioengineered Malaria Protein Biomarker.
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- Author: Monisha S  |  Sain A  |  Jayaprakash NS  |  Senthil Kumar A  | 
Antibodies that target the histidine-rich protein-II biomarker (HRP-II) are being used in rapid diagnostic tests (RDTs) of malaria. HRP-II levels associated with severe malaria are typically greater than 100 ng mL. Unfortunately, genetic variations within the HRP-II gene can reduce the reliability of these RDTs by affecting both sensitivity and specificity. In this study, we developed in-house antibodies against conserved C-terminal 105 amino acids of the HRP-II biomarker to enhance malaria diagnosis using an electrochemical immunosensor technique. Unlike conventional electrochemical immunosensor assays, which use solution-phase enzyme-transducer systems like ferricyanide that suffer from poor current sensitivity and false positives, we constructed a heterogeneous electrochemical immunosensor. This sensor employs highly redox-active thionine (Th) immobilized on a carbon nanofiber (CNF)-based chemically modified electrode (CME) platform. The prepared CME was characterized using several physicochemical techniques, revealing that the oxygen-rich functional groups of CNF serve as active sites for effective antibody binding and immunosensing. Sequential modifications were performed using 2 μL volumes of the polyclonal antibody, antigen (HRP-II), bioengineered monoclonal antibody, and horseradish peroxidase-coupled secondary antibody (Ab2HRP), with each step requiring an incubation time of 3-5 min, resulting in a total working time of 30 ± 5 min. The immunosensor demonstrated excellent sensing signals within a range of 250 pg/mL to 100 ng/mL HRP-II, with a high current sensitivity of 0.813 μA/ng mL. Control experiments with healthy rabbit and human blood serum samples showed no current response, ruling out false positive signals from the assay. For real-time application, high-performance electrochemical immunosensing of rabbit and human blood serum samples spiked with HRP-II was demonstrated with high accuracy.
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To reduce the fetal bovine serum (FBS) and enhance the DF-1 proliferation, three plant peptones and three yeast extracts were incorporated into culture medium. The concentration of FBS in the medium varied from 0 to 10%, and the enhanced cell viability was evaluated within the predetermined range for supplementation. In each specific concentration range, the viability was enhanced by the supplementation compared to the control group. In particular, the medium containing 6.25 mg/mL wheat peptone and 1.25% FBS demonstrated a significant increase in viability. This beneficial effect can be attributed to the incorporation of suitable free amino acids (FAAs), peptides, carbohydrates (excluding free sugars), or trace elements through supplementation. Regarding FAAs, the enhanced cell proliferation by glutamate, glutamine, alanine, and non-essential FAAs was contingent upon the specific type of supplementation. The proliferation was suppressed by serine, histidine, threonine, arginine, tyrosine, valine, methionine, phenylalanine, isoleucine, leucine, essential FAAs, and particularly lysine.
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Genetic background and microbiome drive susceptibility to epicutaneous sensitization and food allergy in adjuvant-free mouse model.
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- Author: Hornikova T  |  Jelinkova A  |  Jiraskova Zakostelska Z  |  Thon T  |  Coufal S  |  Polouckova A  |  Kopelentova E  |  Kverka M  |  Makovicky P  |  Tlaskalova-Hogenova H  |  Sediva A  |  Schwarzer M  |  Srutkova D  | 
The dual allergen exposure hypothesis states that sensitization to food antigens occurs through a damaged skin barrier in individuals with no previous oral tolerance to certain foods. However, the resulting allergic reaction could depend on factors such as the host's genetic predisposition as well as the skin and gut microbiota.
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Due to the widespread use of broad-spectrum antibiotics, the problem of antibiotic resistance has become an increasingly serious global threat. One of the key mechanisms of resistance to beta-lactam antibiotics is the production of beta-lactamase enzymes, which poses a dilemma for clinicians in selecting antibiotics when faced with resistant bacterial infections. However, research on the reversal of bacterial resistance is limited.
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High-Performance Structures of Biopolymer Gels Activated with Scleroprotein Crosslinkers.
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- Author: Prochon M  |  Dzeikala O  |  Szczepanik S  | 
The study explores innovative crosslinking processes for biopolymer gel materials using amino acids and ion-redox initiators to significantly enhance their structural and functional properties. Advanced analytical techniques, including FTIR, Raman spectroscopy, XRD, TEM, TGA, DSC, ToF-SIMS, SEM/EDS, GPC/SEC, and elemental analysis, were employed for comprehensive material characterization. The synthesized materials show potential applications in packaging and medicine, particularly for single-use products with short life cycles. Two crosslinking strategies were developed. The first combines gelatin with polyvinyl alcohol (PVA); keratin hydrolysate; and amino acids such as cysteine, hydroxyproline, proline, and histidine. The second employs endogenous cysteine, activated by ion-redox initiators, leveraging its trans-sulfuration ability to form highly stable polymer networks with optimized mechanical and thermal properties. Notably, the synergy between cysteine and potassium persulfate redox initiators proved particularly effective, making this approach attractive for industrial applications. This study introduces novel crosslinking methods and highlights the potential of amino acid-based strategies for designing advanced biopolymer gels with enhanced properties.
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Selenium reagents are useful for selenoenzyme-mimicking reactions, as well as for organic synthesis. However, the reaction waste containing selenium frequently smells unpleasant and exhibits serious toxicity. Herein, we have developed new-type on-resin selenium reagents, H-UXX···-PAM () and Ac-(X)U*XX···-PAM (), where U and U* represent selenocysteine (U) and -methoxybenzyl (PMB)-protected U, respectively, as recyclable catalysts, in which U-containing peptide chains are linked to the polystyrene resin PAM. Synthesized on-resin selenopeptides - with a variable amino acid sequence were evaluated for their glutathione peroxidase (GPx)-like activity using the UV and H NMR methods, using the reaction between dithiothreitol (DTT) and HO in methanol. It was found that the intramolecular interaction between U and a basic amino acid residue, such as histidine (H) and lysine (K), enhances peroxidase activity through the formation of an NH···Se hydrogen bond. On the other hand, the catalytic activity of - was evaluated in the oxidative cyclization of β,γ-unsaturated acids () into α,β-unsaturated lactones (). Although the yield of was significantly decreased after second- or third-round reaction, due to detachment of the selenium moiety from the resin, the results demonstrated reusability, as well as a substrate scope of as a catalyst. Since U is a natural amino acid, on-resin selenopeptides are potential targets as novel-type green redox catalysts.
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Antioxidant Maillard Reaction Products from Milk Whey: A Food By-Product Valorisation.
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- Author: Bolchini S  |  Nardin T  |  Morozova K  |  Scampicchio M  |  Larcher R  | 
The Maillard reaction (MR) is a key process in food science, producing bioactive compounds with antioxidant properties. This study evaluates the antioxidant potential of MR products (MRPs) from different dairy byproducts-cow cheese whey, goat cheese whey, and cow yoghurt whey-highlighting their applicability in food preservation and waste valorisation. Whey samples were subjected to the MR at 140 °C for 90 min, showing significant amino acid and sugar consumption, particularly arginine, histidine, and lactose. Using a library of potential antioxidant MRPs (molecular weight < 250 Da), 28 key compounds, including 2-pyrrolecarboxaldehyde and maltol isomer, were identified, primarily in cow cheese whey. A complementary high-molecular-weight MRP library (≥250 Da) identified 72 additional antioxidant compounds, with distinct production patterns linked to whey type. Multivariate analyses confirmed that whey type strongly influences MRP profiles. These results highlight the potential of MR to transform whey by-products into valuable sources of natural antioxidants. This approach offers sustainable strategies for enhancing food preservation, reducing food waste, and supporting the targeted use of MRPs in the food industry.
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The Association Between Serum Ergothioneine Concentration and Japanese Dietary Habits: The Third Survey of the ROAD Study.
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- Author: Suzuki K  |  Kaneda Y  |  Izumo T  |  Nakao Y  |  Iidaka T  |  Horii C  |  Muraki S  |  Oka H  |  Kawaguchi H  |  Akune T  |  Hashizume H  |  Yamada H  |  Nakamura K  |  Tanaka S  |  Yoshimura N  | 
As a result of aging societies, the increasing number of older adults requiring nursing care has become a serious issue and the extension of healthy life expectancy has become an urgent priority. Ergothioneine (EGT) is a sulfur-containing amino acid found in foods such as mushrooms. Low EGT blood concentrations have been reported to be associated with the risk of onset and progression of various diseases. However, the distribution of EGT blood concentrations and their association with dietary habits in the Japanese general population remains unclear. This cross-sectional study was conducted using data from the third survey of the Research on Osteoarthritis/osteoporosis Against Disability (ROAD) study, which analyzed 1457 participants (474 men and 983 women) aged ≥ 40 years. Serum EGT concentrations and their association with dietary habits were analyzed. Serum EGT concentrations (1) peaked in the 70s in men and the 60s in women, (2) were higher in women than in men, and (3) showed a significant positive correlation with fish intake and nutrients commonly found in fish. In the present study, we report for the first time an age- and sex-specific serum EGT distribution in a Japanese population and its association with dietary habits, particularly fish intake. These findings help define normal and abnormal EGT levels and suggest new potential sources of EGT.
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