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Environmental Toxicology and... Jun 2024Assessing the harm caused by pollutants in urban ecosystems remains a significant challenge. Traditional ecotoxicological endpoints are often not sensitive enough to...
Assessing the harm caused by pollutants in urban ecosystems remains a significant challenge. Traditional ecotoxicological endpoints are often not sensitive enough to detect the effects of toxicants at environmentally relevant concentrations (≤ng/L). A potential solution is using molecular biology methods to look at small biochemical changes caused by exposure to ng/L concentrations of contaminants. This has been tested in the lab but not conclusively demonstrated in the field. We exposed the freshwater amphipod (Austrochiltonia subtenuis) to water from an urban wetland containing known concentrations of per-and polyfluoroalkyl substances (as well as very low concentrations of pesticides) for 14 days and analyzed their metabolite profiles. Mannose, Myo-inositol, and Isopropyl propionate were found to change in PFAS exposed amphipods, a similar response to that previously observed in laboratory exposures to the same PFAS, but not pesticides. The results give a better understanding of PFAS toxicity at environmentally relevant concentrations and conditions.
PubMed: 38925282
DOI: 10.1016/j.etap.2024.104494 -
International Journal of Pharmaceutics Jun 2024Nanogels are aqueous dispersions of hydrogel particles formed by physically or chemically cross-linked polymer networks of nanoscale size. Herein, we devised a...
Nanogels are aqueous dispersions of hydrogel particles formed by physically or chemically cross-linked polymer networks of nanoscale size. Herein, we devised a straightforward technique to fabricate a novel class of physically cross-linked nanogels via a self-assembly process in water involving α-cyclodextrin and a mannose molecule that was hydrophobically modified using an alkyl chain. The alkyl chain-modified mannose was synthesized in five steps, starting with D-mannose. Subsequently, nanogels were formed by subjecting α-cyclodextrin and the hydrophobically modified mannose to magnetic stirring in water. By adjusting the mole ratio between the hydrophobically modified mannose and α-cyclodextrin, nanogels with an average 100-150 nm diameter were obtained. Physicochemical and structural analyses by H NMR and X-ray diffraction unveiled a supramolecular and hierarchical mechanism underlying the creation of these nanogels. The proposed mechanism of nanogel formation involves two distinct steps: initial interaction of hydrophobically modified mannose with α-cyclodextrin resulting in the formation of inclusion complexes, followed by supramolecular interactions among these complexes, ultimately leading to nanogel formation after 72 h of stirring. We demonstrated the nanogels' ability to encapsulate a short peptide ([p-BuF, R]SHf) as a water-soluble drug model. This discovery holds promise for potentially utilizing these nanogels in drug delivery applications.
PubMed: 38925235
DOI: 10.1016/j.ijpharm.2024.124379 -
Metabolites May 2024Coronary artery disease (CAD) and atherosclerosis pose significant global health challenges, with intricate molecular changes influencing disease progression....
Coronary artery disease (CAD) and atherosclerosis pose significant global health challenges, with intricate molecular changes influencing disease progression. Hypercholesterolemia (HC), hypertension (HT), and diabetes are key contributors to CAD development. Metabolomics, with its comprehensive analysis of metabolites, offers a unique perspective on cardiovascular diseases. This study leveraged metabolomics profiling to investigate the progression of CAD, focusing on the interplay of hypercholesterolemia, hypertension, and diabetes. We performed a metabolomic analysis on 221 participants from four different groups: (I) healthy individuals, (II) individuals with hypercholesterolemia (HC), (III) individuals with both HC and hypertension (HT) or diabetes, and (IV) patients with self-reported coronary artery disease (CAD). Utilizing data from the Qatar Biobank, we combined clinical information, metabolomic profiling, and statistical analyses to identify key metabolites associated with CAD risk. Our data identified distinct metabolite profiles across the study groups, indicating changes in carbohydrate and lipid metabolism linked to CAD risk. Specifically, levels of mannitol/sorbitol, mannose, glucose, and ribitol increased, while pregnenediol sulfate, oleoylcarnitine, and quinolinate decreased with higher CAD risk. These findings suggest a significant role of sugar, steroid, and fatty acid metabolism in CAD progression and point to the need for further research on the correlation between quinolinate levels and CAD risk, potentially guiding targeted treatments for atherosclerosis. This study provides novel insights into the metabolomic changes associated with CAD progression, emphasizing the potential of metabolites as predictive biomarkers.
PubMed: 38921428
DOI: 10.3390/metabo14060292 -
Cells Jun 2024Envenomation by the in the Western Ghats of India (particularly in the Malabar region of Kerala) and the subcontinent island nation of Sri Lanka is known to inflict...
Envenomation by the in the Western Ghats of India (particularly in the Malabar region of Kerala) and the subcontinent island nation of Sri Lanka is known to inflict devastating mortality and morbidity. Currently, bites in India are devoid of anti-venom regimens. A detailed characterization of the venom is essential to stress the need for therapeutic anti-venom. Notably, the deleterious effects of this venom on human blood cells have largely remained less explored. Therefore, in continuation of our previous study, in the present study, we envisioned investigating the effect of venom on the morphological and physiological properties of red blood cells (RBCs). The venom readily induced deleterious morphological changes and, finally, the aggregation of washed RBCs. The aggregation process was independent of the ROS and the intracellular Ca ion concentration. Confocal and scanning electron microscopy (SEM) images revealed the loss of biconcave morphology and massive cytoskeletal disarray. Crenation or serrated plasma membrane projections were evenly distributed on the surface of the RBCs. The venom did not cause the formation of methemoglobin in washed RBCs but was significantly induced in whole blood. Venom did not affect glucose uptake and Na/K -ATPase activity but inhibited glucose 6 phosphate dehydrogenase activity and decreased the fluidity of the plasma membrane. Venom-induced RBC aggregates exhibited pro-coagulant activity but without affecting platelet aggregation. In pre-incubation or co-treatment studies, none of the bioactive compounds, such as melatonin, curcumin, fisetin, berberine, and quercetin, sugars such as mannose and galactose, and therapeutic polyvalent anti-venoms (Bharat and VINS) were inhibited, whereas only N-acetylcysteine and monovalent anti-venom could inhibit venom-induced deleterious morphological changes and aggregation of RBCs. In post-treatment studies, paradoxically, none of the bioactives and anti-venoms, including N-acetylcysteine and monovalent anti-venom, reversed the venom-induced RBC aggregates.
Topics: Animals; Humans; Erythrocytes; Acetylcysteine; Crotalid Venoms; Erythrocyte Aggregation; Antivenins; Calcium; Crotalinae; Reactive Oxygen Species
PubMed: 38920625
DOI: 10.3390/cells13120994 -
Gene Jun 2024Products from stingless bees are rich reservoirs of microbial diversity, including yeasts with fermentative potential. Previously, two Saccharomyces cerevisiae strains,...
Products from stingless bees are rich reservoirs of microbial diversity, including yeasts with fermentative potential. Previously, two Saccharomyces cerevisiae strains, JP14 and IP9, were isolated from Jataí (Tetragonisca angustula) and Iraí (Nannotrigona testaceicornis) bees, respectively, aiming at mead production. Both strains presented great osmotic and sulfite tolerance, and ethanol production, although they have a high free amino nitrogen demand. Herein, their genomes were sequenced, assembled, and annotated, and the variants were compared to the S. cerevisiae S288c reference strain. The final assembly of IP9 and JP14 presented high N50 and BUSCO scores, and more than 6430 protein-coding genes. Additionally, nQuire predicted the ploidy of IP9 as diploid, but the results were not enough to determine the ploidy of JP14. The mitochondrial genomes of IP9 and JP14 presented the same gene content as S288c but the genes were rearranged and fragmented in different patterns. Meanwhile, the genes with mutations of high impact (e.g., indels, gain of stop codon) for both yeasts were enriched for transmembrane transport, electron transfer, oxidoreductase, heme binding, fructose, mannose, and glucose transport, activities related to the respiratory chain and sugar metabolism. The IP9 strain presented copy number gains in genes related to sugar transport and cell morphogenesis; in JP14, genes were enriched for disaccharide metabolism and transport, response to reactive oxygen species, and polyamine transport. On the other hand, IP9 presented copy number losses related to disaccharide, thiamine, and aldehyde metabolism, while JP14 presented depletions related to disaccharide, oligosaccharide, asparagine, and aspartate metabolism. Notably, both strains presented a killer toxin gene, annotated from the assembling of unmapped reads, representing a potential mechanism for the control of other microorganisms population in the environment. Therefore, the annotated genomes of JP14 and IP9 presented a high selective pressure for sugar and nitrogen metabolism and stress response, consistent with their isolation source and fermentative properties.
PubMed: 38914244
DOI: 10.1016/j.gene.2024.148722 -
Archives of Biochemistry and Biophysics Jun 2024Bovine intestinal alkaline phosphatase (biALP), a membrane-bound plasma metalloenzyme, maintains intestinal homeostasis, regulates duodenal surface pH, and protects...
Bovine intestinal alkaline phosphatase (biALP), a membrane-bound plasma metalloenzyme, maintains intestinal homeostasis, regulates duodenal surface pH, and protects against infections caused by pathogenic bacteria. The N-glycans of biALP regulate its enzymatic activity, protein folding, and thermostability, but their structures are not fully reported. In this study, the structures and quantities of the N-glycans of biALP were analyzed by liquid chromatography-electrospray ionization-high energy collision dissociation-tandem mass spectrometry. In total, 48 N-glycans were identified and quantified, comprising high-mannose [6 N-glycans, 33.1% (sum of relative quantities of each N-glycan)], hybrid (6, 11.9%), and complex (36, 55.0%) structures [bi- (13, 26.1%), tri- (16, 21.5%), and tetra-antennary (7, 7.4%)]. These included bisecting N-acetylglucosamine (33, 56.6%), mono- to tri-fucosylation (32, 53.3%), mono- to tri-α-galactosylation (16, 20.7%), and mono- to tetra-β-galactosylation (36, 58.5%). No sialylation was identified. N-glycans with non-bisecting GlcNAc (9, 10.3%), non-fucosylation (10, 13.6%), non-α-galactosylation (26, 46.2%), and non-β-galactosylation (6, 8.4%) were also identified. The activity (100%) of biALP was reduced to 37.3 ± 0.2% (by de-fucosylation), 32.7 ± 2.9% (by de-α-galactosylation), and 0.2 ± 0.2% (by de-β-galactosylation), comparable to inhibition by 10 to 10 mM EDTA, a biALP inhibitor. These results indicate that fucosylated and galactosylated N-glycans, especially β-galactosylation, affected the activity of biALP. This study is the first to identify 48 diverse N-glycan structures and quantities of bovine as well as human intestinal ALP and to demonstrate the importance of the role of fucosylation and galactosylation for maintaining the activity of biALP.
PubMed: 38914216
DOI: 10.1016/j.abb.2024.110069 -
ACS Bio & Med Chem Au Jun 2024Carbohydrate recognition is imperative for the induction of sperm acrosomal exocytosis (AE), an essential phenomenon in mammalian fertilization. In mouse sperm,...
Carbohydrate recognition is imperative for the induction of sperm acrosomal exocytosis (AE), an essential phenomenon in mammalian fertilization. In mouse sperm, polynorbornene 100-mers displaying fucose or mannose moieties were effective at inducing AE. In contrast, glycopolymers exhibiting glucose sugars resulted in no AE activation. To further elucidate the role of ligand density on the activation of AE in mouse sperm, a triple-stain flow cytometry assay was employed to determine the efficacy of polynorbornene block copolymers with barbell-like sequences as initiators of AE. Triblock (ABA or ABC) copolymers were synthesized by ring-opening metathesis polymerization (ROMP) with one or two activating sugars, mannose or fucose, and one nonactivating sugar, glucose. The active ligand fractions in the polymers varied from 10, 20, or 40%. Simultaneously, random copolymers comprising 20% activating ligands were prepared to confirm the importance of ligand positionality in AE activation in mouse sperm. Polynorbornene 100-mers possessing two 10-mer blocks of activating sugars were the most effective copolymers at inducing AE with levels of AE comparable to their homopolymer counterparts and more effective than their random analogues. Small-angle X-ray scattering (SAXS) was then performed to verify that there were no differences in the conformations of the glycopolymers contributing to their varying AE activity. SAXS data analysis confirmed that all of the glycopolymers assumed semiflexible cylindrical structures with similar radii and Kuhn lengths. These findings suggest that the overall ligand density of the sugar moieties in the polymer is less important than the positionality of short blocks of high-density ligands for AE activation in mouse sperm.
PubMed: 38911911
DOI: 10.1021/acsbiomedchemau.4c00012 -
Frontiers in Immunology 2024Complement activation is considered to contribute to the pathogenesis of severe SARS-CoV-2 infection, mainly by generating potent immune effector mechanisms including a...
Complement activation is considered to contribute to the pathogenesis of severe SARS-CoV-2 infection, mainly by generating potent immune effector mechanisms including a strong inflammatory response. Involvement of the lectin complement pathway, a major actor of the innate immune anti-viral defense, has been reported previously. It is initiated by recognition of the viral surface Spike glycoprotein by mannose-binding lectin (MBL), which induces activation of the MBL-associated protease MASP-2 and triggers the proteolytic complement cascade. A role for the viral nucleoprotein (N) has also been reported, through binding to MASP-2, leading to protease overactivation and potentiation of the lectin pathway. In the present study, we reinvestigated the interactions of the SARS-CoV-2 N protein, produced either in bacteria or secreted by mammalian cells, with full-length MASP-2 or its catalytic domain, in either active or proenzyme form. We could not confirm the interaction of the N protein with the catalytic domain of MASP-2 but observed N protein binding to proenzyme MASP-2. We did not find a role of the N protein in MBL-mediated activation of the lectin pathway. Finally, we showed that incubation of the N protein with MASP-2 results in proteolysis of the viral protein, an observation that requires further investigation to understand a potential functional significance in infected patients.
Topics: Mannose-Binding Protein-Associated Serine Proteases; Humans; SARS-CoV-2; Complement Pathway, Mannose-Binding Lectin; COVID-19; Protein Binding; Coronavirus Nucleocapsid Proteins; Complement Activation; Mannose-Binding Lectin; Phosphoproteins
PubMed: 38911852
DOI: 10.3389/fimmu.2024.1419165 -
ACS Omega Jun 2024Mushroom polysaccharides are important bioactive compounds derived from mushrooms with various beneficial properties. In this study, the chemical characterization and...
Mushroom polysaccharides are important bioactive compounds derived from mushrooms with various beneficial properties. In this study, the chemical characterization and bioactivities of polysaccharide extracts from four different edible mushrooms, Donk, (Fr.) Quél., (Fr.) Fr., and (Scop.) Singer were studied. Glucose (13.24-56.02%), galactose (14.18-64.05%), mannose (2.18-18.13%), fucose (1.21-5.78%), and arabinose (0.04-5.43%) were identified in all polysaccharide extracts by GC-MS (gas chromatography-mass spectrometry). FT-IR (Fourier transform infrared spectroscopy) confirmed the presence of characteristic carbohydrate patterns. H NMR suggested that all polysaccharide extracts had α- and β-d-mannopyranose, d-glucopyranose, d-galactopyranose, α-l-arabinofuranose, and α-l-fucopyranose residues. Approximate molecular weights of polysaccharide extracts were determined by HPLC (high-performance liquid chromatography). The best antioxidant activity was found in polysaccharide extract in DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging (39.03% at 800 μg/mL), CUPRAC (cupric reducing antioxidant capacity) (A: 387.50 μg/mL), and PRAP (phosphomolybdenum reducing antioxidant power) (A: 384.08 μg/mL) assays. polysaccharide extract showed the highest antioxidant activity in ABTS scavenging (IC: 734.09 μg/mL), β-carotene-linoleic acid (IC: 472.16 μg/mL), and iron chelating (IC: 180.35 μg/mL) assays. Significant anticancer activity was found in polysaccharide extract on HT-29 (IC: 46.49 μg/mL) and HepG2 (IC: 48.50 μg/mL) cell lines and polysaccharide extract on the HeLa cell line (IC: 51.64 μg/mL). Also, polysaccharide extract possessed prominent AChE (acetylcholinesterase) inhibition activity (49.14% at 200 μg/mL).
PubMed: 38911755
DOI: 10.1021/acsomega.4c00322 -
Biomacromolecules Jun 2024A major shortcoming associated with the application of enzymes in drug synergism originates from the lack of site-specific, multifunctional nanomedicine. This study...
A major shortcoming associated with the application of enzymes in drug synergism originates from the lack of site-specific, multifunctional nanomedicine. This study introduces catalytic nanocompartments (CNCs) made of a mixture of PDMS--PMOXA diblock copolymers, decorated with glycooligomer tethers comprising eight mannose-containing repeating units and coencapsulating two enzymes, providing multifunctionality by their in situ parallel reactions. Beta-glucuronidase (GUS) serves for local reactivation of the drug hymecromone, while glucose oxidase (GOx) induces cell starvation through glucose depletion and generation of the cytotoxic HO. The insertion of the pore-forming peptide, melittin, facilitates diffusion of substrates and products through the membranes. Increased cell-specific internalization of the CNCs results in a substantial decrease in HepG2 cell viability after 24 h, attributed to simultaneous production of hymecromone and HO. Such parallel enzymatic reactions taking place in nanocompartments pave the way to achieve efficient combinatorial cancer therapy by enabling localized drug production along with reactive oxygen species (ROS) elevation.
PubMed: 38910355
DOI: 10.1021/acs.biomac.4c00526