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1.
Nat Commun ; 15(1): 3035, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600088

RESUMEN

People living with HIV (PLWH) experience increased vulnerability to premature aging and inflammation-associated comorbidities, even when HIV replication is suppressed by antiretroviral therapy (ART). However, the factors associated with this vulnerability remain uncertain. In the general population, alterations in the N-glycans on IgGs trigger inflammation and precede the onset of aging-associated diseases. Here, we investigate the IgG N-glycans in cross-sectional and longitudinal samples from 1214 women and men, living with and without HIV. PLWH exhibit an accelerated accumulation of pro-aging-associated glycan alterations and heightened expression of senescence-associated glycan-degrading enzymes compared to controls. These alterations correlate with elevated markers of inflammation and the severity of comorbidities, potentially preceding the development of such comorbidities. Mechanistically, HIV-specific antibodies glycoengineered with these alterations exhibit a reduced ability to elicit anti-HIV Fc-mediated immune activities. These findings hold potential for the development of biomarkers and tools to identify and prevent premature aging and comorbidities in PLWH.


Asunto(s)
Envejecimiento Prematuro , Infecciones por VIH , Masculino , Humanos , Femenino , Inmunoglobulina G , Estudios Transversales , Envejecimiento , Inflamación/complicaciones , Polisacáridos
2.
Methods Mol Biol ; 2788: 49-66, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38656508

RESUMEN

Calibrated size exclusion chromatography (SEC) is a useful tool for the analysis of molecular dimensions of polysaccharides. The calibration takes place with a set of narrow distributed dextran standards and peak position technique. Adapted columns systems and dissolving processes enable for the adequate separation of carbohydrate polymers. Plant-extracted fructan (a homopolymer with low molar mass and excellent water solubility) and mucilage (differently structured, high molar mass heteropolysaccarides that include existing supramolecular structures, and require a long dissolving time) are presented as examples of the versatility of this technique. Since narrow standards similar to the samples (chemically and structurally) are often unavailable, it must be noted that the obtained molar mass values and distributions by this method are only apparent (relative) values, expressed as dextran equivalents.


Asunto(s)
Cromatografía en Gel , Peso Molecular , Polisacáridos , Cromatografía en Gel/métodos , Polisacáridos/química , Polisacáridos/análisis , Dextranos/química , Fructanos/química , Fructanos/análisis , Calibración
3.
Methods Mol Biol ; 2788: 81-95, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38656510

RESUMEN

Atomic force microscopy (AFM) has broken boundaries in the characterization of the supramolecular architecture of cell wall assemblies and single cell wall polysaccharides at the nanoscale level. Moreover, AFM provides an opportunity to evaluate the mechanical properties of cell wall material which is not possible with any other method. However, in the case of plant tissue, the critical step is a smart sample preparation that should not affect the polysaccharide structure or assembly and on the other hand should consider device limitations, especially scanner ranges. In this chapter, the protocols from the sample preparation, including isolation of cell wall material and extraction of cell wall polysaccharide fractions, through AFM imaging of polysaccharide assemblies and single molecules until an image analysis to obtain quantitative data characterizing the biopolymers are presented.


Asunto(s)
Pared Celular , Microscopía de Fuerza Atómica , Microscopía de Fuerza Atómica/métodos , Pared Celular/ultraestructura , Pared Celular/química , Polisacáridos/química , Polisacáridos/análisis
4.
J Hazard Mater ; 470: 134172, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38569340

RESUMEN

Xyloglucan endotransglucosylase/hydrolases (XTH) are cell wall-modifying enzymes important in plant response to abiotic stress. However, the role of XTH in cadmium (Cd) tolerance in ramie remains largely unknown. Here, we identified and cloned BnXTH1, a member of the XTH family, in response to Cd stress in ramie. The BnXTH1 promoter (BnXTH1p) demonstrated that MeJA induces the response of BnXTH1p to Cd stress. Moreover, overexpressing BnXTH1 in Boehmeria nivea increased Cd tolerance by significantly increasing the Cd content in the cell wall and decreasing Cd inside ramie cells. Cadmium stress induced BnXTH1-expression and consequently increased xyloglucan endotransglucosylase (XET) activity, leading to high xyloglucan contents and increased hemicellulose contents in ramie. The elevated hemicellulose content increased Cd chelation onto the cell walls and reduced the level of intracellular Cd. Interestingly, overexpressing BnXTH1 significantly increased the content of Cd in vacuoles of ramie and vacuolar compartmentalization genes. Altogether, these results evidence that Cd stress induced MeJA accumulation in ramie, thus, activating BnXTH1 expression and increasing the content of xyloglucan to enhance the hemicellulose binding capacity and increase Cd chelation onto cell walls. BnXTH1 also enhances the vacuolar Cd compartmentalization and reduces the level of Cd entering the organelles and soluble solution.


Asunto(s)
Boehmeria , Cadmio , Pared Celular , Vacuolas , Cadmio/toxicidad , Cadmio/metabolismo , Pared Celular/metabolismo , Pared Celular/efectos de los fármacos , Boehmeria/metabolismo , Boehmeria/efectos de los fármacos , Vacuolas/metabolismo , Vacuolas/efectos de los fármacos , Glicosiltransferasas/metabolismo , Glicosiltransferasas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Polisacáridos/metabolismo , Oxilipinas/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Glucanos/metabolismo , Xilanos/metabolismo , Estrés Fisiológico/efectos de los fármacos
5.
Microbiome ; 12(1): 77, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664737

RESUMEN

BACKGROUND: The deep sea represents the largest marine ecosystem, driving global-scale biogeochemical cycles. Microorganisms are the most abundant biological entities and play a vital role in the cycling of organic matter in such ecosystems. The primary food source for abyssal biota is the sedimentation of particulate organic polymers. However, our knowledge of the specific biopolymers available to deep-sea microbes remains largely incomplete. One crucial rate-limiting step in organic matter cycling is the depolymerization of particulate organic polymers facilitated by extracellular enzymes (EEs). Therefore, the investigation of active EEs and the microbes responsible for their production is a top priority to better understand the key nutrient sources for deep-sea microbes. RESULTS: In this study, we conducted analyses of extracellular enzymatic activities (EEAs), metagenomics, and metatranscriptomics from seawater samples of 50-9305 m from the Mariana Trench. While a diverse array of microbial groups was identified throughout the water column, only a few exhibited high levels of transcriptional activities. Notably, microbial populations actively transcribing EE genes involved in biopolymer processing in the abyssopelagic (4700 m) and hadopelagic zones (9305 m) were primarily associated with the class Actinobacteria. These microbes actively transcribed genes coding for enzymes such as cutinase, laccase, and xyloglucanase which are capable of degrading phytoplankton polysaccharides as well as GH23 peptidoglycan lyases and M23 peptidases which have the capacity to break down peptidoglycan. Consequently, corresponding enzyme activities including glycosidases, esterase, and peptidases can be detected in the deep ocean. Furthermore, cell-specific EEAs increased at 9305 m compared to 4700 m, indicating extracellular enzymes play a more significant role in nutrient cycling in the deeper regions of the Mariana Trench. CONCLUSIONS: Transcriptomic analyses have shed light on the predominant microbial population actively participating in organic matter cycling in the deep-sea environment of the Mariana Trench. The categories of active EEs suggest that the complex phytoplankton polysaccharides (e.g., cutin, lignin, and hemicellulose) and microbial peptidoglycans serve as the primary nutrient sources available to deep-sea microbes. The high cell-specific EEA observed in the hadal zone underscores the robust polymer-degrading capacities of hadal microbes even in the face of the challenging conditions they encounter in this extreme environment. These findings provide valuable new insights into the sources of nutrition, the key microbes, and the EEs crucial for biopolymer degradation in the deep seawater of the Mariana Trench. Video Abstract.


Asunto(s)
Bacterias , Metagenómica , Nutrientes , Peptidoglicano , Fitoplancton , Polisacáridos , Agua de Mar , Polisacáridos/metabolismo , Agua de Mar/microbiología , Fitoplancton/metabolismo , Fitoplancton/genética , Nutrientes/metabolismo , Peptidoglicano/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Bacterias/aislamiento & purificación , Microbiota
6.
Mol Genet Genomic Med ; 12(4): e2422, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38622837

RESUMEN

BACKGROUND: Congenital disorders of glycosylation (CDG) are a type of inborn error of metabolism (IEM) resulting from defects in glycan synthesis or failed attachment of glycans to proteins or lipids. One rare type of CDG is caused by homozygous or compound heterozygous loss-of-function variants in mannosidase alpha class 2B member 2 (MAN2B2). To date, only two cases of MAN2B2-CDG have been reported worldwide. METHODS: Trio whole-exome sequencing (Trio-WES) was conducted to screen for candidate variants. N-glycan profiles were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). MAN2B2 expression was evaluated by western blotting. MX dynamin like GTPase 1 (MX1) function was estimated via Thogoto virus (THOV) minireplicon assay. RESULTS: Trio-WES identified compound heterozygous MAN2B2 (hg19, NM_015274.1) variants (c.384G>T; c.926T>A) in a CDG patient. This patient exhibited metabolic abnormalities, symptoms of digestive tract dysfunction, infection, dehydration, and seizures. Novel immune dysregulation characterized by abnormal lymphocytes and immunoglobulin was observed. The MAN2B2 protein level was not affected, while LC-MS/MS showed obvious disruption of N-glycans and N-linked glycoproteins. CONCLUSION: We described a CDG patient with novel phenotypes and disruptive N-glycan profiling caused by compound heterozygous MAN2B2 variants (c.384G>T; c.926T>A). Our findings broadened both the genetic and clinical spectra of CDG.


Asunto(s)
Trastornos Congénitos de Glicosilación , Humanos , Cromatografía Liquida , Trastornos Congénitos de Glicosilación/genética , Trastornos Congénitos de Glicosilación/diagnóstico , Glicoproteínas , Polisacáridos , Espectrometría de Masas en Tándem
7.
PLoS One ; 19(4): e0301604, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38635649

RESUMEN

The red abalone (Haliotis rufescens) represents North America's most important aquaculture species. Its hepatopancreas is rich in cellulases and other polysaccharide-degrading enzymes, which provide it the remarkable ability to digest cellulose-rich macroalgae; nevertheless, its cellulolytic systems are poorly explored. This manuscript describes some functional and structural properties of an endogenous trimeric glycosylated endoglucanase from H. rufescens. The purified enzyme showed a molecular mass of 23.4 kDa determined by MALDI-TOF mass spectrometry, which behaved as a homotrimer in gel filtration chromatography and zymograms. According to the periodic acid-Schiff reagent staining, detecting sugar moieties in SDS-PAGE gel confirmed that abalone cellulase is a glycoprotein. Hydrolysis of cello-oligosaccharides and p-nitrophenyl-ß-D-glucopyranosides confirmed its endo/exoactivity. A maximum enzyme activity toward 0.5% (w/v) carboxymethylcellulose of 53.9 ± 1.0 U/mg was achieved at 45°C and pH 6.0. We elucidated the abalone cellulase primary structure using proteases and mass spectrometry methods. Based on these results and using a bioinformatic approach, we identified the gene encoding this enzyme and deduced its full-length amino acid sequence; the mature protein comprised 177 residues with a calculated molecular mass of 19.1 kDa and, according to sequence similarity, it was classified into the glycosyl-hydrolase family 45 subfamily B. An AlphaFold theoretical model and docking simulations with cellopentaose confirmed that abalone cellulase is a ß-sheet rich protein, as also observed by circular dichroism experiments, with conserved catalytic residues: Asp26, Asn109, and Asp134. Interestingly, the AlphaFold-Multimer analysis indicated a trimeric assembly for abalone cellulase, which supported our experimental findings. The discovery and characterization of these enzymes may contribute to developing efficient cellulose bioconversion processes for biofuels and sustainable bioproducts.


Asunto(s)
Celulasa , Gastrópodos , Animales , Celulasa/metabolismo , Gastrópodos/genética , Secuencia de Aminoácidos , Celulosa/metabolismo , Polisacáridos
8.
Glycobiology ; 34(6)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38579012

RESUMEN

Biological experiments are often conducted in vitro using immortalized cells due to their accessibility and ease of propagation compared to primary cells and live animals. However, immortalized cells may present different proteomic and glycoproteomic characteristics from the primary cell source due to the introduction of genes that enhance proliferation (e.g. CDK4) or enable telomere lengthening. To demonstrate the changes in phenotype upon CDK4-transformation, we performed LC-MS/MS glycomic and proteomic characterizations of a human lung cancer primary cell line (DTW75) and a CDK4-transformed cell line (GL01) derived from DTW75. We observed that the primary and CDK4-transformed cells expressed significantly different levels of sialylated, fucosylated, and sialofucosylated N-glycans. Specifically, the primary cells expressed higher levels of hybrid- and complex-type sialylated N-glycans, while CDK4-transformed cells expressed higher levels of complex-type fucosylated and sialofucosylated N-glycans. Further, we compared the proteomic differences between the cell lines and found that CDK4-transformed cells expressed higher levels of RNA-binding and adhesion proteins. Further, we observed that the CDK4-transformed cells changed N-glycosylation after 31 days in cell culture, with a decrease in high-mannose and increase in fucosylated, sialylated, and sialofucosylated N-glycans. Identifying these changes between primary and CDK4-transformed cells will provide useful insight when adapting cell lines that more closely resemble in vivo physiological conditions.


Asunto(s)
Quinasa 4 Dependiente de la Ciclina , Neoplasias Pulmonares , Polisacáridos , Proteoma , Humanos , Quinasa 4 Dependiente de la Ciclina/metabolismo , Quinasa 4 Dependiente de la Ciclina/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Proteoma/metabolismo , Proteoma/análisis , Polisacáridos/metabolismo , Línea Celular Tumoral , Glicosilación , Glicómica , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/genética
9.
Glycobiology ; 34(6)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38590172

RESUMEN

Human noroviruses, globally the main cause of viral gastroenteritis, show strain specific affinity for histo-blood group antigens (HBGA) and can successfully be propagated ex vivo in human intestinal enteroids (HIEs). HIEs established from jejunal stem cells of individuals with different ABO, Lewis and secretor geno- and phenotypes, show varying susceptibility to such infections. Using bottom-up glycoproteomic approaches we have defined and compared the N-linked glycans of glycoproteins of seven jejunal HIEs. Membrane proteins were extracted, trypsin digested, and glycopeptides enriched by hydrophilic interaction liquid chromatography and analyzed by nanoLC-MS/MS. The Byonic software was used for glycopeptide identification followed by hands-on verifications and interpretations. Glycan structures and attachment sites were identified from MS2 spectra obtained by higher-energy collision dissociation through analysis of diagnostic saccharide oxonium ions (B-ions), stepwise glycosidic fragmentation of the glycans (Y-ions), and peptide sequence ions (b- and y-ions). Altogether 694 unique glycopeptides from 93 glycoproteins were identified. The N-glycans encompassed pauci- and oligomannose, hybrid- and complex-type structures. Notably, polyfucosylated HBGA-containing glycopeptides of the four glycoproteins tetraspanin-8, carcinoembryonic antigen-related cell adhesion molecule 5, sucrose-isomaltase and aminopeptidase N were especially prominent and were characterized in detail and related to donor ABO, Lewis and secretor types of each HIE. Virtually no sialylated N-glycans were identified for these glycoproteins suggesting that terminal sialylation was infrequent compared to fucosylation and HBGA biosynthesis. This approach gives unique site-specific information on the structural complexity of N-linked glycans of glycoproteins of human HIEs and provides a platform for future studies on the role of host glycoproteins in gastrointestinal infectious diseases.


Asunto(s)
Glicoproteínas , Humanos , Glicoproteínas/metabolismo , Glicoproteínas/química , Proteómica/métodos , Antígenos de Grupos Sanguíneos/metabolismo , Antígenos de Grupos Sanguíneos/química , Polisacáridos/química , Polisacáridos/metabolismo , Fucosa/metabolismo , Fucosa/química , Fenotipo , Glicosilación , Sistema del Grupo Sanguíneo ABO/metabolismo , Sistema del Grupo Sanguíneo ABO/química
10.
Biochim Biophys Acta Gen Subj ; 1868(6): 130617, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38614280

RESUMEN

BACKGROUND: Sialylation of glycoproteins, including integrins, is crucial in various cancers and diseases such as immune disorders. These modifications significantly impact cellular functions and are associated with cancer progression. Sialylation, catalyzed by specific sialyltransferases (STs), has traditionally been considered to be regulated at the mRNA level. SCOPE OF REVIEW: Recent research has expanded our understanding of sialylation, revealing ST activity changes beyond mRNA level variations. This includes insights into COPI vesicle formation and Golgi apparatus maintenance and identifying specific target proteins of STs that are not predictable through recombinant enzyme assays. MAJOR CONCLUSIONS: This review summarizes that Golgi-associated pathways largely influence the regulation of STs. GOLPH3, GORAB, PI4K, and FAK have become critical elements in sialylation regulation. Some STs have been revealed to possess specificity for specific target proteins, suggesting the presence of additional, enzyme-specific regulatory mechanisms. GENERAL SIGNIFICANCE: This study enhances our understanding of the molecular interplay in sialylation regulation, mainly focusing on the role of integrin and FAK. It proposes a bidirectional system where sialylations might influence integrins and vice versa. The diversity of STs and their specific linkages offer new perspectives in cancer research, potentially broadening our understanding of cellular mechanisms and opening avenues for new therapeutic approaches in targeting sialylation pathways.


Asunto(s)
Integrinas , Polisacáridos , Sialiltransferasas , Humanos , Integrinas/metabolismo , Sialiltransferasas/metabolismo , Polisacáridos/metabolismo , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Animales , Aparato de Golgi/metabolismo
11.
Cell Rep ; 43(4): 114105, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38619967

RESUMEN

Natural killer (NK) cells are primary defenders against cancer precursors, but cancer cells can persist by evading immune surveillance. To investigate the genetic mechanisms underlying this evasion, we perform a genome-wide CRISPR screen using B lymphoblastoid cells. SPPL3, a peptidase that cleaves glycosyltransferases in the Golgi, emerges as a top hit facilitating evasion from NK cytotoxicity. SPPL3-deleted cells accumulate glycosyltransferases and complex N-glycans, disrupting not only binding of ligands to NK receptors but also binding of rituximab, a CD20 antibody approved for treating B cell cancers. Notably, inhibiting N-glycan maturation restores receptor binding and sensitivity to NK cells. A secondary CRISPR screen in SPPL3-deficient cells identifies B3GNT2, a transferase-mediating poly-LacNAc extension, as crucial for resistance. Mass spectrometry confirms enrichment of N-glycans bearing poly-LacNAc upon SPPL3 loss. Collectively, our study shows the essential role of SPPL3 and poly-LacNAc in cancer immune evasion, suggesting a promising target for cancer treatment.


Asunto(s)
Células Asesinas Naturales , Polisacáridos , Humanos , Polisacáridos/metabolismo , Células Asesinas Naturales/metabolismo , Células Asesinas Naturales/inmunología , Amino Azúcares/metabolismo , Genómica/métodos , Rituximab/farmacología , Rituximab/metabolismo , Línea Celular Tumoral
12.
Mar Drugs ; 22(4)2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38667770

RESUMEN

Shrimp processing generates substantial waste, which is rich in valuable components such as polysaccharides, proteins, carotenoids, and fatty acids. This review provides a comprehensive overview of the valorization of shrimp waste, mainly shrimp shells, focusing on extraction methods, bioactivities, and potential applications of these bioactive compounds. Various extraction techniques, including chemical extraction, microbial fermentation, enzyme-assisted extraction, microwave-assisted extraction, ultrasound-assisted extraction, and pressurized techniques are discussed, highlighting their efficacy in isolating polysaccharides, proteins, carotenoids, and fatty acids from shrimp waste. Additionally, the bioactivities associated with these compounds, such as antioxidant, antimicrobial, anti-inflammatory, and antitumor properties, among others, are elucidated, underscoring their potential in pharmaceutical, nutraceutical, and cosmeceutical applications. Furthermore, the review explores current and potential utilization avenues for these bioactive compounds, emphasizing the importance of sustainable resource management and circular economy principles in maximizing the value of shrimp waste. Overall, this review paper aims to provide insights into the multifaceted aspects of shrimp waste valorization, offering valuable information for researchers, industries, and policymakers interested in sustainable resource utilization and waste-management strategies.


Asunto(s)
Carotenoides , Ácidos Grasos , Polisacáridos , Animales , Ácidos Grasos/aislamiento & purificación , Ácidos Grasos/química , Ácidos Grasos/farmacología , Polisacáridos/farmacología , Polisacáridos/aislamiento & purificación , Polisacáridos/química , Carotenoides/farmacología , Carotenoides/aislamiento & purificación , Carotenoides/química , Penaeidae/química , Proteínas/aislamiento & purificación , Residuos , Humanos , Administración de Residuos/métodos , Antioxidantes/farmacología , Antioxidantes/aislamiento & purificación , Antioxidantes/química
13.
Mar Drugs ; 22(4)2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38667787

RESUMEN

Porphyran, a sulfated polysaccharide found in various species of marine red algae, has been demonstrated to exhibit diverse bioactivities, including anti-inflammatory effects. However, the protective effects of porphyran against cerebral ischemia and reperfusion (IR) injury have not been investigated. The aim of this study was to examine the neuroprotective effects of porphyran against brain IR injury and its underlying mechanisms using a gerbil model of transient forebrain ischemia (IR in the forebrain), which results in pyramidal cell (principal neuron) loss in the cornu ammonis 1 (CA1) subregion of the hippocampus on day 4 after IR. Porphyran (25 and 50 mg/kg) was orally administered daily for one week prior to IR. Pretreatment with 50 mg/kg of porphyran, but not 25 mg/kg, significantly attenuated locomotor hyperactivity and protected pyramidal cells located in the CA1 area from IR injury. The pretreatment with 50 mg/kg of porphyran significantly suppressed the IR-induced activation and proliferation of microglia in the CA1 subregion. Additionally, the pretreatment significantly inhibited the overexpressions of nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing protein-3 (NLRP3) inflammasome complex, and pro-inflammatory cytokines (interleukin 1 beta and interleukin 18) induced by IR in the CA1 subregion. Overall, our findings suggest that porphyran exerts neuroprotective effects against brain IR injury, potentially by reducing the reaction (activation) and proliferation of microglia and reducing NLRP3 inflammasome-mediated neuroinflammation.


Asunto(s)
Región CA1 Hipocampal , Gerbillinae , Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Enfermedades Neuroinflamatorias , Fármacos Neuroprotectores , Daño por Reperfusión , Sefarosa/análogos & derivados , Animales , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Inflamasomas/metabolismo , Inflamasomas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Masculino , Daño por Reperfusión/tratamiento farmacológico , Región CA1 Hipocampal/efectos de los fármacos , Región CA1 Hipocampal/patología , Región CA1 Hipocampal/metabolismo , Enfermedades Neuroinflamatorias/tratamiento farmacológico , Modelos Animales de Enfermedad , Microglía/efectos de los fármacos , Isquemia Encefálica/tratamiento farmacológico , Polisacáridos/farmacología , Neuronas/efectos de los fármacos , Células Piramidales/efectos de los fármacos , Células Piramidales/metabolismo
14.
Mar Drugs ; 22(4)2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38667805

RESUMEN

Three Laminaria japonica polysaccharides (LJPs) extracted via water extraction (LJP-W), acid extraction (LJP-A), and enzymatic extraction (LJP-E) were used as raw materials to be cross-linked with chitosan and polyvinyl alcohol to prepare hydrogels. Compared with conventional hydrogel systems, all three types of LJP-based polysaccharide hydrogels exhibited better swelling properties (14 times their original weight) and the absorption ability of simulated body fluid (first 2 h: 6-10%). They also demonstrated better rigidity and mechanical strength. Young's modulus of LJP-E was 4 times that of the blank. In terms of hemostatic properties, all three polysaccharide hydrogels did not show significant cytotoxic and hemolytic properties. The enzyme- and acid-extracted hydrogels (LJP-Gel-A and LJP-Gel-E) demonstrated better whole-blood coagulant ability compared with the water-extracted hydrogel (LJP-Gel-W), as evidenced by the whole blood coagulation index being half that of LJP-Gel-W. Additionally, the lactate dehydrogenase viabilities of LJP-Gel-A and LJP-Gel-E were significantly higher, at about four and three times those of water extraction, respectively. The above results suggested that LJP-Gel-A and LJP-Gel-E exhibited better blood coagulation capabilities than LJP-Gel-W, due to their enhanced platelet enrichment and adhesion properties. Consequently, these hydrogels are more conducive to promoting coagulation and have good potential for wound hemostasis.


Asunto(s)
Coagulación Sanguínea , 60578 , Hemostáticos , Hidrogeles , Laminaria , Polisacáridos , Hidrogeles/química , Hidrogeles/farmacología , Laminaria/química , Polisacáridos/química , Polisacáridos/farmacología , Polisacáridos/aislamiento & purificación , Coagulación Sanguínea/efectos de los fármacos , Hemostáticos/farmacología , Hemostáticos/química , Hemostáticos/aislamiento & purificación , Humanos , Animales , Quitosano/química , Quitosano/farmacología , Alcohol Polivinílico/química , Hemostasis/efectos de los fármacos , Hemólisis/efectos de los fármacos
15.
Toxins (Basel) ; 16(4)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38668613

RESUMEN

BACKGROUND: Snakebite envenomation (SBE) causes diverse toxic effects in humans, including disability and death. Current antivenom therapies effectively prevent death but fail to block local tissue damage, leading to an increase in the severity of envenomation; thus, seeking alternative treatments is crucial. METHODS: This study analyzed the potential of two fucoidan sulfated polysaccharides extracted from brown seaweeds Fucus vesiculosus (FVF) and Undaria pinnatifida (UPF) against the fibrinogen or plasma coagulation, proteolytic, and phospholipase A2 (PLA2) activities of Bothrops jararaca, B. jararacussu, and B. neuwiedi venom. The toxicity of FVF and UPF was assessed by the hemocompatibility test. RESULTS: FVF and UPF did not lyse human red blood cells. FVF and UPF inhibited the proteolytic activity of Bothrops jararaca, B. jararacussu, and B. neuwiedi venom by approximately 25%, 50%, and 75%, respectively, while all venoms led to a 20% inhibition of PLA2 activity. UPF and FVF delayed plasma coagulation caused by the venoms of B. jararaca and B. neuwiedi but did not affect the activity of B. jararacussu venom. FVF and UPF blocked the coagulation of fibrinogen induced by all these Bothropic venoms. CONCLUSION: FVF and UPF may be of importance as adjuvants for SBE caused by species of Bothrops, which are the most medically relevant snakebite incidents in South America, especially Brazil.


Asunto(s)
Coagulación Sanguínea , Bothrops , Venenos de Crotálidos , 60578 , Fucus , Fosfolipasas A2 , Polisacáridos , Undaria , 60573 , Animales , Fucus/química , Polisacáridos/farmacología , Polisacáridos/aislamiento & purificación , Fosfolipasas A2/metabolismo , Coagulación Sanguínea/efectos de los fármacos , Undaria/química , Venenos de Crotálidos/toxicidad , Venenos de Crotálidos/enzimología , Algas Marinas/química , Antivenenos/farmacología , Proteolisis/efectos de los fármacos , Humanos , 60560
16.
Cell Rep ; 43(4): 114012, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38573856

RESUMEN

Plasmodium falciparum is a human-adapted apicomplexan parasite that causes the most dangerous form of malaria. P. falciparum cysteine-rich protective antigen (PfCyRPA) is an invasion complex protein essential for erythrocyte invasion. The precise role of PfCyRPA in this process has not been resolved. Here, we show that PfCyRPA is a lectin targeting glycans terminating with α2-6-linked N-acetylneuraminic acid (Neu5Ac). PfCyRPA has a >50-fold binding preference for human, α2-6-linked Neu5Ac over non-human, α2-6-linked N-glycolylneuraminic acid. PfCyRPA lectin sites were predicted by molecular modeling and validated by mutagenesis studies. Transgenic parasite lines expressing endogenous PfCyRPA with single amino acid exchange mutants indicated that the lectin activity of PfCyRPA has an important role in parasite invasion. Blocking PfCyRPA lectin activity with small molecules or with lectin-site-specific monoclonal antibodies can inhibit blood-stage parasite multiplication. Therefore, targeting PfCyRPA lectin activity with drugs, immunotherapy, or a vaccine-primed immune response is a promising strategy to prevent and treat malaria.


Asunto(s)
Eritrocitos , Plasmodium falciparum , Polisacáridos , Proteínas Protozoarias , Eritrocitos/parasitología , Eritrocitos/metabolismo , Humanos , Proteínas Protozoarias/metabolismo , Proteínas Protozoarias/genética , Plasmodium falciparum/metabolismo , Polisacáridos/metabolismo , Malaria Falciparum/parasitología , Animales , Lectinas/metabolismo , Lectinas/genética , Antígenos de Protozoos/metabolismo , Antígenos de Protozoos/inmunología , Antígenos de Protozoos/genética , Unión Proteica
17.
Planta ; 259(5): 113, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38581452

RESUMEN

MAIN CONCLUSION: Carbohydrates are hydrolyzed by a family of carbohydrate-active enzymes (CAZymes) called glycosidases or glycosyl hydrolases. Here, we have summarized the roles of various plant defense glycosidases that possess different substrate specificities. We have also highlighted the open questions in this research field. Glycosidases or glycosyl hydrolases (GHs) are a family of carbohydrate-active enzymes (CAZymes) that hydrolyze glycosidic bonds in carbohydrates and glycoconjugates. Compared to those of all other sequenced organisms, plant genomes contain a remarkable diversity of glycosidases. Plant glycosidases exhibit activities on various substrates and have been shown to play important roles during pathogen infections. Plant glycosidases from different GH families have been shown to act upon pathogen components, host cell walls, host apoplastic sugars, host secondary metabolites, and host N-glycans to mediate immunity against invading pathogens. We could classify the activities of these plant defense GHs under eleven different mechanisms through which they operate during pathogen infections. Here, we have provided comprehensive information on the catalytic activities, GH family classification, subcellular localization, domain structure, functional roles, and microbial strategies to regulate the activities of defense-related plant GHs. We have also emphasized the research gaps and potential investigations needed to advance this topic of research.


Asunto(s)
Glicósido Hidrolasas , Polisacáridos , Glicósido Hidrolasas/química , Glicósido Hidrolasas/metabolismo , Polisacáridos/metabolismo , Carbohidratos , Plantas/metabolismo , Glicósidos/metabolismo
18.
Anal Chem ; 96(15): 5741-5745, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38573003

RESUMEN

Fucosylation is an important structural feature of glycans and plays an essential role in the regulation of glycoprotein functions. Fucosylation can be classified into core- (CF) and antenna-fucosylation (AF, also known as (sialyl-) Lewis) based on the location on N-glycans, and they perform distinct biological functions. In this study, core- and antenna-fucosylated N-glycans on human serum glycoproteins that hold great clinical application values were systematically characterized at the site-specific level using StrucGP combined with the recently developed fucosylation assignment method. The results showed that fucosylation was widely distributed on serum glycoproteins, with 50% of fucosylated glycopeptides modified by AF N-glycans, 37% by CF N-glycans, and 13% by dual-fucosylated N-glycans. Interestingly, CF and AF N-glycans preferred to modify different groups of serum glycoproteins with different tissue origins and were involved in distinctive biological processes. Specifically, AF N-glycoproteins are mainly from the liver and participated in complement activation, blood coagulation, and endopeptidase activities, while CF N-glycoproteins originate from diverse tissues and are mainly involved in cell adhesion and signaling transduction. These data further enhanced our understanding of fucosylation on circulation glycoproteins.


Asunto(s)
Glicoproteínas , Hígado , Humanos , Glicoproteínas/química , Glicosilación , Hígado/metabolismo , Polisacáridos/química , Fucosa/química
19.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1485-1493, 2024 Mar.
Artículo en Chino | MEDLINE | ID: mdl-38621932

RESUMEN

Chuanxiong Rhizoma is a well-known Sichuan-specific herbal medicine. Its original plant, Ligusticum chuanxiong, has been cultivated asexually for a long time. L. chuanxiong has sexual reproductive disorders, which restricts its germplasm innovation. However, there is little research on the reproductive system of L. chuanxiong. This study is based on a comparative anatomical research approach, using morphological dissection, paraffin sectioning, staining and compression, and combined with scanning electron microscopy technology, to observe and compare the flowers, fruits, and seeds at various stages of reproductive growth of L. chuanxiong and its wild relative L. sinense. The results showed that the meiosis of pollen mother cells is abnormal in L. chuanxiong anthers, and the size and number of microspores are uneven and inconsistent in the tetrad stage. tapetum cells are not completely degenerated during anther development. During the pollen ripening stage, there are fine cracks in the anther wall, while most anthers could not release pollen normally. The surface of mature pollen grains is concave and partially deformed, and the pollens are all inactive and cannot germinate in vitro. The starch, polysaccharides, and lipids in the pollen were insufficient. The filaments of L. chuanxiong are short at the flowering stage and recurved downward. Double-hanging fruits were observed in the fruiting stage, being wrinkled; with shriveled seeds. Compared with L. sinense at the same stage, the anthers of L. sinense developed normally, and the pollen grains are vigorous and can germinate in vitro. The double-hanging fruits of L. sinense are full and normal; at the flowering period, the filaments are long and erect, significantly higher than the stigma. Mature blastocysts are visible in the ovary of both L. chuanxiong and L. sinense, and there is no significant difference in stigmas. The conclusion is that during the development of L. chuanxiong stamens, the meiosis of pollen mother cells is abnormal, and tetrad, tapetum, filament and other pollen structures develop abnormally. L. chuanxiong has the characteristic of male infertility, which is an important reason for its sexual reproductive disorders.


Asunto(s)
Ligusticum , Reproducción , Polen , Flores , Polisacáridos
20.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1540-1548, 2024 Mar.
Artículo en Chino | MEDLINE | ID: mdl-38621937

RESUMEN

This study aims to reveal the effects of maltodextrin(MD) on the water adsorption and thermodynamic properties of Codonopsis Radix(DS) spray-dried powder by determining the moisture and energy changes of the powder in the process of moisture absorption. The static weighing method was used to obtain the isothermal water adsorption data of the spray-dried powder in 6 saturated salt solutions(KAc, MgCl_2·6H_2O, K_2CO_3, NaBr, NaCl, and KCl) at 3 temperatures(25, 35, and 45 ℃). Six models were used for fitting of the water adsorption process, and the most suitable model was selected based on the model performance. Furthermore, the corresponding net equivalent adsorption heat and differential entropy were calculated, and the adsorption entropy change was integrated. The linear relationship between net equivalent adsorption heat and differential entropy was drawn based on the entropy-enthalpy complementarity theory. The results showed that the water adsorption properties of DS and DS-MD spray-dried powder followed the type Ⅲ isotherm and was well fitted by the GAB model. The monolayer water content M_0 decreased with the increase in temperature. At the same temperature, the M_0 of DS spray-dried powder decreased after the addition of MD. The net equivalent adsorption heat and differential entropy of DS and DS-MD spray-dried powder decreased with the increase in water content, which presented a linear relationship. The addition of MD decreased the water activity corresponding to the lowest integral adsorption entropy of the powder, and the system became more stable. The results indicated that the spray-dried powder became more stable after the addition of MD.


Asunto(s)
Codonopsis , Polisacáridos , Agua , Adsorción , Polvos , Termodinámica
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