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Localization of sialic acid in kidney glomeruli: regionalization in the podocyte plasma membrane and loss in experimental nephrosis.

Sialic acid residues were localized by electron microscopy in renal glomeruli of normal and puromycin-treated rats with a cytochemical technique that utilized the Limax flavus lectin. In Lowicryl K4M thin sections from normal rats, sialic acid residues were found along the plasma membrane of the various glomerular cell types and in the glomerular basement membrane as well as the mesangial matrix. In NaDodSO4/PAGE, sialic acid residues of normal glomeruli were mainly confined to a 140-kDa protein previously identified as podocalyxin. The distribution of sialic acid residues in the podocyte plas

Sialic acid exacerbates polycystic ovary syndrome in mice by modulating gut microbiota-mediated bile acid metabolism and FXR activation.

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder in women. Accumulating evidence indicates that gut dysbiosis and metabolic disturbances are associated with the pathogenesis of PCOS. However, the mechanisms by which metabolic alterations influence gut homeostasis and contribute to PCOS progression remain poorly understood. Here, we show that N-acetylneuraminic acid (Neu5Ac) exacerbates dehydroepiandrosterone (DHEA)-induced PCOS phenotypes in female mice in a gut microbiota-dependent manner. Specifically, Neu5Ac promotes the expansion of the gut Ligilactobacillus salivarius (L

Dataset on inflammatory proteins expressions and sialic acid levels in apolipoprotein E-deficient mice with administration of N-acetylneuraminic acid and/or quercetin.

The data presented in this article describe an effect of N-acetylneuraminic acid and/or quercetin on the inflammatory proteins expressions (TNF-α, ICAM-1, VCAM-1 and MOMA-2) and the N-acetylneuraminic acid (NANA) levels of apolipoprotein E-deficient mice that are given a high-fat diet. Protein expression was performed by immunohistochemical imaging and NANA was quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) or semi-quantified using Image-Pro Plus software after ligation with fluorescein-5-thiosemicarbazide (FTSC). Further interpretation and discussion could be found at

Dietary sialic acid intake and incident dementia: evidence from a large prospective cohort study.

PURPOSE: Beneficial effects of sialic acid on cognition have been most often seen in cognitive development in infant models, whereas the relevant evidence from ageing population studies remains limited. We aimed to investigate the associations of dietary sialic acids and their subtypes (Neu5Ac and Neu5Gc) with the incident dementia in a large prospective study. METHODS: A total of 210,796 middle-aged and older participants from UK Biobank were included in this study. Dietary sialic acids intake was estimated using repeated 24-h dietary recall questionnaires. Cox proportional hazards models we…

A model of free sialic acid storage disorder reveals hypomyelinating leukodystrophy and Purkinje cell degeneration.

Free sialic acid storage disorder (FSASD) is a rare, neurodegenerative, lysosomal storage disease caused by biallelic variants in SLC17A5, which encodes the lysosomal sialic acid exporter, sialin. Although clinical severity varies, all affected individuals exhibit progressive neurological decline and characteristic lysosomal and urinary accumulation of free sialic acid. No US Food and Drug Administration-approved therapies currently exist, and the molecular underpinnings of central nervous system (CNS) dysfunction remain poorly defined. To model the most prevalent FSASD-associated allele, we g

Amino-blocking sialic acid linkage specific alkylamidation for qualitative and quantitative analysis of sialylated glycoproteins.

Protein glycosylation is a pivotal post-translational modification involved in diverse physiological processes. Sialic acid, a terminal monosaccharide in glycans, exhibits critical biological functions and disease associations, yet its linkage isomers (α2,3- vs. α2,6-) remain challenging to be discriminated by conventional LC-MS/MS due to identical masses and similar chromatographic behaviors. Although sialic acid linkage-specific alkylamidation (SALSA) based on lactone ring-opening ammonolysis has been widely applied to glycopeptides, we observed undesired glycopeptide-glycopeptide condensati

Development of mumps virus-specific sialidase imaging probes through chemical modifications of sialic acid.

Some viruses, such as mumps virus (MuV), possess sialidases that cleave terminal sialic acids, primarily N-acetylneuraminic acid (Neu5Ac), from glycans. Previously, we developed a sialidase fluorescent imaging probe (BTP3-Neu5Ac) and visualized cells infected with sialidase-expressing viruses. However, BTP3-Neu5Ac could not specifically identify these viruses, as it reacted with a wide range of sialidases from viruses, bacteria, and mammals. Here, to confer specificity of BTP3-Neu5Ac to MuV sialidase, which features a hydrophobic cavity extending toward the C5 position of bound Neu5Ac, we eval…

Sialic acid metabolism of oral bacteria and its potential role in colorectal cancer and Alzheimer's disease.

Sialic acid metabolism in oral bacteria is a complex process involving nutrient acquisition, immune evasion, cell surface modification, and the production of metabolites that contribute to bacterial persistence and virulence in the oral cavity. In addition to causing various periodontal diseases, certain oral pathogenic bacteria, such as Porphyromonas gingivalis, Tannerella forsythia, and Fusobacterium nucleatum, can induce inflammatory reactions and influence the immunity of host cells. These associations with host cells are linked to various diseases, particularly colorectal cancer and Alzhe

On the function of TRAP substrate-binding proteins: Conformational variation of the sialic acid binding protein SiaP.

Tripartite ATP-independent periplasmic (TRAP) transporters are analogous to ABC transporters in that they use a substrate-binding protein to scavenge metabolites (e.g., N-acetylneuraminate) and deliver them to the membrane components for import. TRAP substrate-binding proteins are thought to bind the substrate using a two-state (open and closed) induced-fit mechanism. We solved the structure of the TRAP N-acetylneuraminate substrate-binding protein from Aggregatibacter actinomycetemcomitans (AaSiaP) in both the open ligand-free and closed liganded conformations. Surprisingly, we also observed

NDV нацелен на вторжение в малярийный паразит через взаимодействие клеточной сиальной кислоты.

Мерозоиты используют сиальные кислоты на поверхности красных кровяных клеток (RBC) для быстрого присоединения к RBC и вторжения в них. Вирус болезни Ньюкасла (NDV) свидетельствует о сильной близости к мембранным сиалистическим кислотам. Инкубация NDV паразитами малярии в зависимости от дозы снижает ее клеточную жизнеспособность. Антиплазмодиальная активность NDV является специфической, поскольку инкубация японского энцефалита, утка энтерит, инфекционный бронхит и грипп не повлияли на распространение паразита. Интересно, что NDV сокращает более чем на 80% вторжение, когда РБЦ проходят предварит

Совпадение в аннотации оригинала
Merozoites utilize sialic acids on the red blood cell (RBC) cell surface to rapidly adhere to and invade the RBCs. Newcastle disease virus (NDV) displays a strong affinity toward membrane-bound sialic acids. Incubation of NDV with the malaria parasites dose-dependently reduces its cellular viability. The antiplasmodial activity of NDV is specific, as incubat…

Effect of Non-Surgical Periodontal Therapy on the Serum Sialic Acid Levels in Diabetic Patients with Periodontitis.

Sialic acid (SA), a family of acetylated derivatives of neuraminic acid, an acute phase reactant by itself. It usually occurs as a terminal … rker, for early detection of disease evolution and more robust therapy efficacy measurements. Serum sialic acids were estimated in Indian population by diphenylamine method and Thiobarbituric acid method. The average values were 68 ± 2.6 mg percent by DPA method and 56 ± 5 mg percent by TBA (thiobarbituric acid assay) method. Age and sex showed no influence on …

Levels of Salivary Sialic Acid in Children with Autism Spectrum Disorder; Could It Be Related to Stereotypes and Hyperactivity?

OBJECTIVE: Sialic acid (Sia) is an essential nutrient for brain development, learning, memory and cognition and plays a role in neurodevelopment of infants. The aim of this study was to determine whether Sia levels are significantly associated with the autism spectrum disorder (ASD). METHODS: Forty-six ASD children and 30 typically developing children aged 3 to 10 years were included in the study. Behavioral symptoms in ASD children was assessed by the Autism Behavior Checklist (AuBC), the Childhood Autism Rating Scale, and the Aberrant Behavior Checklist (ABC). After the collection of saliva

Sialic acid deficiency is associated with oxidative stress leading to muscle atrophy and weakness in GNE myopathy.

Sialic acids are monosaccharides found in terminal sugar chains of cell surfaces and proteins; they have various biological functions and have been implicated in health and disease. Genetic defects of the GNE gene which encodes a critical bifunctional enzyme for sialic acid biosynthesis, lead to GNE myopathy, a disease manifesting with progressive muscle atrophy and weakness. The likely mechanism of disease is a lack of sialic acids. There remains, however, an unexplained link between hyposialylation and the muscle atrophy and weakness. In this study, we found that muscle proteins were highly …

Direct and label-free influenza virus detection based on multisite binding to sialic acid receptors.

A system to discriminate human or avian influenza A remains a highly sought-after tool for prevention of influenza pandemics in humans. Selective binding of the influenza A viral hemagglutinin (HA) to specific sialic acid (SA) receptors (Neu5Acα(2-6)Gal in humans, Neu5Acα(2-3)Gal in birds) is determined by the genotype of the HA and neuraminidase (NA) segments, making it one of the key characteristics that distinguishes human or avian influenza A virus. Here we demonstrate the direct detection of whole H1N1 influenza A virus using 6'-sialyllactose (Neu5Acα(2-6)Galβ(1-4)Glc, 6SL)-immobilized go

Synergistic anti-tumor effect of bullfrog sialic acid-binding lectin and pemetrexed in malignant mesothelioma.

Diabetes mellitus is a significant risk factor for urinary tract infections (UTIs), which occur more frequently, have a more severe course, and show a greater tendency to recur in affected individuals. Metabolic disturbances, particularly hyperglycemia and glucosuria, promote bacterial growth while simultaneously impairing innate and adaptive immune responses. In addition, diabetes-related complications, such as autonomic neuropathy, contribute to bladder dysfunction and urinary stasis, further facilitating bacterial colonization. Epidemiological evidence indicates a two- to four-fold increase

Prenatal screening of sialic acid storage disease and confirmation in cultured fibroblasts by LC-MS/MS.

Sialic acid storage disease (SASD) is an inborn error resulting from defects in the lysosomal membrane protein sialin. The SASD phenotypical spectrum ranges from a severe presentation, infantile sialic acid storage disease (ISSD) which may present as hydrops fetalis, to a relatively mild form, Salla disease. Screening for SASD is performed by determination of free sialic acid (FSA) in urine or amniotic fluid supernatant (AFS). Subsequent diagnosis of SASD is performed by quantification of FSA in cultured fibroblasts and by mutation analysis of the sialin gene, SLC17A5. We describe simple quant