Search Results (3,361)

Lemon peel, which contains a wide variety of antioxidant compounds and biopolymers, is an interesting byproduct for valorization. In this study, pectin and cellulose were obtained from lemon peel with 36% and 23% extraction yields. Meanwhile, when evaluating the extraction of secondary metabolites using various enzymes, it was found that their concentrations increased the most in the case of pectin methylesterase, by up to 21.7% for eriocitrin, although the solid residue was not affected spectroscopically by the enzymatic activity. In contrast, enzyme mixes with β-glucosidase activity showed no presence of the O-glycosylated flavonoids, suggesting their hydrolysis into the aglycones. Full article

N-Acetyl-D-mannosamine (ManNAc) and N-acetylneuraminic acid (Neu5Ac) are important components of glycosylation, affecting numerous physiologic processes. The effects of age, body mass index (BMI), race, or sex on serum levels of ManNAc and Neu5Ac are poorly understood. However, these associations are of substantial interest. Simultaneous quantification of ManNAc and Neu5Ac, using liquid chromatography tandem mass spectrometry (LC-MS/MS), was developed and validated for human serum samples. This method has high sensitivity, specificity, and reproducibility, with limits of detection as low as 1.02 ng/mL for ManNAc or 1.14 ng/mL for Neu5Ac. A set of 155 serum samples from the Adventist Health Study 2 (AHS-2) cohort was analyzed. Concentrations of conjugated Neu5Ac were 35.1 ± 9.4 µg/mL and 33.0 ± 9.5 µg/mL in black and white participants, respectively. Conjugated and total Neu5Ac levels were significantly higher in women, with p-values of 0.029 and 0.026, respectively. The free forms of Neu5Ac were 594 ± 421 ng/mL and 439 ± 168 ng/mL in black and white participants, respectively. Similarly, conjugated and total ManNAc levels were higher in black participants, at 1.81 ± 0.81 µg/mL and 1.90 ± 0.83 µg/mL, compared to 1.32 ± 0.52 µg/mL and 1.41 ± 0.53 µg/mL in white participants (both cases, p < 0.001). Free ManNAc was 93.1 ± 36.2 ng/mL in black and 89 ± 20.2 ng/mL in white participants. Subjects with higher BMI tend to have higher free ManNAc (p = 0.041). Furthermore, older subjects tend to have higher free (p ≤ 0.001) and total (p = 0.045) ManNAc. The improved LC-MS/MS quantification method should facilitate further investigations. Full article

Glycosylation serves as an effective strategy to enhance the solubility, bioavailability, and pharmacological activity of polyhydroxyphenols. In this study, we explored the glycosylation of natural and natural-inspired phenolic compounds using the glycosyltransferase AbCGT and evaluated the anti-renal fibrotic potential of the resulting glycosides. Among them, 1,3,5,8-tetrahydroxyxanthone 5-O-β-D-glucopyranoside (2-1a), synthesized via the regioselective 5-O-glycosylation of demethylbellidifolin, demonstrated significant anti-renal fibrotic activity. In contrast, its homologous glycosyltransferase, UGT73AE1, predominantly glycosylated demethylbellidifolin at the 3-OH position. Molecular docking studies revealed the structural basis for this regioselectivity difference. To enhance the production of 2-1a, we established a UDP-glucose (UDPG) recycling system by coupling AbCGT with Glycine max sucrose synthase (GmSuSy) and subsequently optimized the reaction conditions. Furthermore, targeted mutagenesis of AbCGT informed by molecular docking analysis identified a F138A mutant that enhanced glycosylation yield by 2.3-fold. This work develops a novel glycosyltransferase-based catalytic system and identifies a new compound with potential anti-renal fibrotic activity. Full article

The landscape of first-line treatment for metastatic non-small cell lung cancer (NSCLC) without actionable driver mutations is rapidly evolving, currently dominated by pembrolizumab-based regimens. This review discusses the unique molecular characteristics of cemiplimab, a newer anti-PD-1 antibody, and defines its optimal positioning against established standards. Cemiplimab is a fully human IgG4 monoclonal antibody distinguished by two key features: an engineered hinge-region mutation that prevents Fab-arm exchange, ensuring exceptional molecular stability which minimizes anti-drug antibody (ADA) risks associated with unstable molecules; and a unique interaction with PD-1 glycosylation sites, potentially enhancing binding efficacy. These structural advantages may be particularly relevant in histologies like squamous NSCLC, where accumulating somatic mutations drive high neoantigen loads and heightened immune responses, creating an environment historically prone to ADA formation. Based on data from the pivotal EMPOWER-Lung program, we highlight cemiplimab’s exceptional promise in specific populations. Firstly, in the EMPOWER-Lung 1 trial, cemiplimab monotherapy demonstrated extraordinary survival benefits in a pre-specified analysis of the distinct “ultra-high” PD-L1 expression subgroup (TPS ≥90%), potentially surpassing historical benchmarks. Secondly, cemiplimab displays consistent, robust efficacy in challenging-to-treat squamous histology, both as monotherapy for patients with high PD-L1 expression and in combination with chemotherapy for patients with PD-L1 < 50%. In conclusion, cemiplimab establishes a unique therapeutic niche for patients with squamous histology and ultra-high PD-L1 expression, likely driven by its distinct structural stability and reduced immunogenicity. Full article

Background: This study assesses the robustness of a legacy N-glycan profiling method for the therapeutic antibody MAB1 with different Peptide-N-glycosidase F (PNGase F) enzyme sources, solid phase extraction (SPE) cartridges, and reagent stability, aligning with ICH Q14 lifecycle management principles. Glycosylation profiling is critical for therapeutic antibodies as it influences both function and pharmacokinetics. Method: The legacy N-glycan profiling method, 2-aminobenzoic acid (2-AA) labeling combined with normal-phase HPLC, was re-evaluated to confirm consistent analytical performance in the context of evolving regulatory expectations. The evaluation focused on three key factors: PNGase F enzyme sources, solid-phase extraction (SPE) cartridges, and reagent stability. Results: Commercial PNGase F enzymes showed various performances, with some sources yielding significant differences. Several SPE cartridges were also tested, with certain formats displaying poor recovery and high variability, particularly for sialylated glycans. In addition, reagent stability studies revealed rapid degradation of the labeling reagent within a few days. Conclusions: These results underscore the importance of risk control, continual improvement, and lifecycle management to ensure reliable glycosylation analysis and the sustained robustness of legacy methods. Full article

Background: ALG13-CDG is an X-linked N-linked glycosylation disorder caused by pathogenic variants in the glycosyltransferase ALG13, leading to severe neurological manifestations. Despite the clear CNS involvement, the impact of ALG13 dysfunction on human brain glycosylation and neurodevelopment remains unknown. We hypothesize that ALG13-CDG causes brain-specific hypoglycosylation that disrupts neurodevelopmental pathways and contributes directly to cortical network dysfunction. Methods: We generated iPSC-derived human cortical organoids (hCOs) from individuals with ALG13-CDG to define the impact of hypoglycosylation on cortical development and function. Electrophysiological activity was assessed using MEA recordings and integrated with multiomic profiling, including scRNA-seq, proteomics, glycoproteomics, N-glycan imaging, lipidomics, and metabolomics. X-inactivation status was evaluated in both iPSCs and hCOs. Results: ALG13-CDG hCOs showed reduced glycosylation of proteins involved in ECM organization, neuronal migration, lipid metabolism, calcium homeostasis, and neuronal excitability. These pathway disruptions were supported by proteomic and scRNA-seq data and included altered intercellular communication. Trajectory analyses revealed mistimed neuronal maturation with early inhibitory and delayed excitatory development, indicating an E/I imbalance. MEA recordings demonstrated early network hypoactivity with reduced firing rates, immature burst structure, and shortened axonal projections, while transcriptomic and proteomic signatures suggested emerging hyperexcitability. Altered lipid and GlcNAc metabolism, along with skewed X-inactivation, were also observed. Conclusions: Our study reveals that ALG13-CDG is a disorder of brain-specific hypoglycosylation that disrupts key neurodevelopmental pathways and destabilizes cortical network function. Through integrated multiomic and functional analyses, we identify early network hypoactivity, mistimed neuronal maturation, and evolving E/I imbalance that progresses to compensatory hyperexcitability, providing a mechanistic basis for seizure vulnerability. These findings redefine ALG13-CDG as disorders of cortical network instability, offering a new framework for targeted therapeutic intervention. Full article

A novel steviol glycoside, Rebaudioside D17, was identified from the leaf extract of Stevia rebaudiana Bertoni. This compound features a rare β-1→4 glycosidic linkage between two glucose units at the C19 position, distinguishing it from its structural isomer, Rebaudioside D. The aim of this study was to isolate and characterize Rebaudioside D17 and investigate its biosynthetic origin. The compound was isolated and structurally characterized using comprehensive NMR spectroscopy including ¹H, ¹³C, COSY, NOESY, Heteronuclear Single Quantum Coherence–Distortionless Enhancement by Polarization Transfer (HSQC-DEPT), Heteronuclear Multiple Bond Correlation (HMBC), Heteronuclear Single Quantum Coherence–Total Correlated Spectroscopy (HSQC-TOCSY), along with mass spectrometry analysis. A tentative biosynthetic pathway is proposed, involving Rebaudioside E19, a putative intermediate bearing the same β-1→4 glycosidic linkage at C19. Rebaudioside E19 may serve as a common precursor to both Rebaudioside D17 and Rebaudioside U3, a minor steviol glycoside previously reported in Stevia rebaudiana leaf extract, which also contains the same β-1→4 glycosidic linkage. The discovery of Rebaudioside D17 expands the known diversity of steviol glycosides and provides new insights into glycosylation patterns in Stevia rebaudiana, which may support the development and production of novel sweeteners with improved sensory and physicochemical properties. Full article

Weed control is mainly carried out using synthetic herbicides, which represent 62.6% of the total pesticides sold. However, some plants produce allelochemicals that inhibit the growth of other plants, and these substances can be isolated and used as natural herbicides. This study aimed to evaluate the allelopathic, cytotoxic, genotoxic, and antigenotoxic potential of the ethanol extract (EE), hexane (HEX), dichloromethane (DCM), ethyl acetate (EA) and hydroethanol (HE) fractions obtained from Tecoma stans flowers. Nuclear magnetic resonance (NMR) was used to characterize the compounds present in the samples. The allelopathic activity was tested using Allium cepa and Lactuca sativa seeds, and the cytotoxicity, genotoxicity and antigenotoxicity were evaluated using A. cepa seeds. The saturated and unsaturated fatty acids ω-3 and ω-6, terpenes, flavonoids, and phenolic acids with coumaroyl or glycosyl derivatives were characterized in the samples. The HEX and DCM fractions significantly inhibited germination and root growth, effects associated with fatty acids and phenolic compounds. The EA fraction exhibits genotoxic potential at higher concentrations tested. The extract and fractions reduced the genotoxicity induced by glyphosate and atrazine, reversing chromosomal abnormalities. These results demonstrate the possible use of the extract and fractions as natural sources of allelochemicals, but safe dosage validation is required. Full article

Autoantibodies have long been regarded as passive reflections of immune dysregulation in connective tissue diseases (CTDs). Recent advances in systems immunology and molecular pathology have fundamentally redefined them as active molecular fingerprints that delineate distinct disease endophenotypes with predictive power for clinical trajectories and therapeutic responses. Rather than mere epiphenomena, autoantibodies encode precise information about dominant immune pathways, organ tropism, and pathogenic mechanisms. This review synthesizes emerging evidence that autoantibody repertoires—defined by specificity, structural properties, and functional characteristics—stratify patients beyond traditional clinical taxonomy into discrete pathobiological subsets. Specific signatures such as anti-MDA5 in rapidly progressive interstitial lung disease, anti-RNA polymerase III in scleroderma renal crisis, and anti-Ro52/TRIM21 in systemic overlap syndromes illustrate how serological profiles predict outcomes with remarkable precision. Mechanistically, autoantibody pathogenicity is modulated by immunoglobulin isotype distribution, Fc glycosylation patterns, and tissue-specific receptor expression—variables that determine whether an antibody functions as a biomarker or pathogenic effector. The structural heterogeneity of autoantibodies, shaped by cytokine microenvironments and B-cell subset imprinting, creates a dynamic continuum between pro-inflammatory and regulatory states. The integration of serological, transcriptomic, and imaging data establishes a precision medicine framework: autoantibodies function simultaneously as disease classifiers and therapeutic guides. This endophenotype-driven approach is already influencing trial design and patient stratification in systemic lupus erythematosus, systemic sclerosis, and inflammatory myopathies, and is reshaping both clinical practice and scientific taxonomy in CTDs. Recognizing autoantibodies as endophenotypic determinants aligns disease classification with pathogenic mechanism and supports the transition towards immunologically informed therapeutic strategies. Full article

A key function of naturally occurring antibodies is to control pathologically altered cells, such as those with aberrant glycosylation. Age-related diminution in the pool of B cells producing these immunoglobulins is linked to impaired anti-tumor immunity. In this study, the levels of antibodies against tumor-associated carbohydrate antigens (TACAs)—common in gastric cancer (GC) and other malignancies—were analyzed in 235 treatment-naïve GC patients (stages I–IV) and 76 healthy donors using a printed glycan array (PGA). We found that anti-glycan IgM levels, but not IgG, reduced with age in both patients and donors. Crucially, IgM levels against most glycans were significantly lower in the GC cohort compared with healthy donors, a trend that remained after age adjustment. Furthermore, an immunohistochemical analysis revealed that human anti-GalNAcα (Tn) antibodies—a well-characterized TACA in gastrointestinal cancers—bound to tumor cells and exhibited perinuclear and membrane staining in non-tumor surface cells within the same organ. These data support the hypothesis that gastric cancer patients have reduced levels of anti-glycan IgMs, which are responsible for the early recognition of transformed cells. This specific immunodeficiency may contribute to a permissive environment for tumor development. Full article

Circulating irisin, a myokine implicated in energy expenditure and adipose tissue regulation, has been increasingly studied as a potential biomarker of metabolic dysfunction. This study evaluated the relationship between serum irisin and metabolic indices, including the atherogenic index of plasma (AIP), the lipid accumulation product (LAP), and hypertriglyceridemic-waist (HTGW) phenotype in individuals with prediabetes (PreDM) and newly diagnosed type 2 diabetes mellitus (T2DM). A total of 138 participants (48 PreDM, 90 T2DM) were assessed for anthropometric, glycemic, and lipid parameters. Serum irisin levels were measured by enzyme-linked immunosorbent assay (ELISA) and correlated with insulin resistance indices (Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), Quantitative Insulin Sensitivity Check Index (QUICKI)), glycemic control (glycosylated hemoglobin A1c (HbA1c)), and composite lipid markers (total triglycerides-to-high-density lipoprotein cholesterol (TG/HDL-C)). Group differences were evaluated using non-parametric tests; two-way ANOVA assessed interactions between phenotypes and markers; multiple linear regression (MLR) and logistic regression models explored independent associations with metabolic indices and HTGW; receiver operating characteristic (ROC) analyses compared global and stratified model performance. Serum irisin was significantly lower in T2DM than in PreDM (median 140.4 vs. 230.7 ng/mL, p < 0.0001). Irisin levels remained comparable between males and females in both groups. Post hoc analysis shows that lipid indices and irisin primarily distinguish HTGW phenotypes, especially in T2DM. In both groups, irisin correlated inversely with HOMA-IR, AIP, and TG/HDL-C, and positively with QUICKI, indicating a possible compensatory role in early insulin resistance. MLR analyses revealed no independent relationship between irisin and either AIP or LAP in PreDM, while in T2DM, waist circumference remained the strongest negative predictor of irisin. Logistic regression identified age, male sex, and HbA1c as independent predictors of the HTGW phenotype, while irisin contributed modestly to overall model discrimination. ROC curves demonstrated good discriminative performance (AUC = 0.806 for global; 0.794 for PreDM; 0.813 for T2DM), suggesting comparable predictive accuracy across glycemic stages. In conclusion, irisin levels decline from prediabetes to overt diabetes and are inversely linked to lipid accumulation and insulin resistance but do not independently predict the HTGW phenotype. These findings support irisin’s role as an integrative indicator of metabolic stress rather than a stand-alone biomarker. Incorporating irisin into multi-parameter metabolic panels may enhance early detection of cardiometabolic risk in dysglycemic populations. Full article

Oral squamous cell carcinoma (OSCC) is an aggressive disease with a glycoproteomically unmapped progression and a low five-year survival rate. Thus, the aim of this pilot study was to explore the N-glycosylation pattern differences in malignant, adjacent mucosal and healthy tissues in the context of OSCC. Oral mucosal soft tissue samples was obtained by incisional biopsy from five patients with OSCC, both from the malignant and the opposite healthy gingival sides, and from seven age-sex-matched healthy controls. The collected tissues were homogenized, followed by N-glycan profiling of the endoglycosidase-released and fluorophore-labeled carbohydrates using capillary electrophoresis with ultra-sensitive laser-induced fluorescent detection (CE-LIF). Six out of the twenty-two identified N-glycan structures, including glycogens, showed significant (p < 0.05) differences between the malignant tissue samples of the OSCC patients and the healthy controls. Comparing the healthy and the positive control oral mucosal samples, differences in four N-glycan structures were revealed, while only one alteration was observed between the N-glycan profiles of the malignant tumor and positive control samples. However, the results are presented descriptively, reflecting the limited sample size of the pilot study, it shows the potential of high-resolution CE-LIF-based glyocoanalytical protocol to be highly efficient and sensitive for glycobiomarker-based molecular diagnostics of oral malignant lesions. Full article

Background: Metabolically associated fatty liver disease (MASLD) constitutes a major burden. Glucagon-like peptide-1 agonists (GLP-1) could improve hepatic steatosis as well as weight loss. However, the effect of GLP-1 agonists on patients with and without diabetes and the effect of newer drugs (dual and triple agonists) are unclear. Objective: To investigate the effect of GLP-1 agonists, including dual and triple agonists, in patients with metabolic-associated liver steatosis and steatohepatitis, while exploring their effect on patients with and without type 2 diabetes. Methods: We searched PubMed, Scopus, and Web of Science in October 2025 for randomized parallel controlled trials that investigated the effect of GLP-1 agonists in patients with MASLD or metabolic-associated steatohepatitis (MASH). We assessed the quality of the included studies using Cochrane ROB2. We performed the analysis using RevMan 5.4. We performed subgroup analysis based on the status of diabetes, the control group, and the class of GLP-1 agonist (single, dual, or triple). Results: We included twenty studies. Compared to the control group, GLP-1 agonists were associated with a statistically significant increase in the resolution of MASH without worsening fibrosis (RR 3.03, p < 0.0001) and at least one stage of liver fibrosis without the worsening of MASH compared to the control group (RR: 1.45, p < 0.00001). GLP-1 agonists were associated with a statistically significant weight reduction (SMD −1.11, p < 0.0001), glycosylated hemoglobin (SMD −0.81, p < 0.00001), levels of aspartate aminotransferase (SMD −0.48, p = 0.008), and alanine aminotransferase (SMD −0.54, p = 0.008). However, in patients without type 2 diabetes, GLP-1 agonists had no significant effect on weight loss (SMD −0.97, p = 0.12) or improvement in fibrosis (RR 1.54, p = 0.24). There was a statistically significant increase in the overall adverse events (RR 1.10, p < 0.00001), while there was no significant difference in serious adverse events (p = 0.35). Conclusions: GLP-1 agonists improved liver fibrosis, steatohepatitis, weight loss, HbA1c, and liver enzymes in patients with MASLD or MASH. Overall, GLP-1 agonists were associated with a significantly higher risk of adverse events compared to the control, while serious adverse events were comparable between both groups. There was no significant effect on weight loss or improvement in fibrosis in patients without type 2 diabetes. However, there was a limited number of studies in this population. Thus, further research is needed before recommendations can be made for this subgroup. Full article

This study investigated the effect of superheated steam (SS) assisted glycosylation modification on the flavor profile of oyster peptides (OP), and explored the correlation between key flavor compounds and glycosylation degree using Gas Chromatography–Ion Mobility Spectrometry (GC-IMS) and nano-scale Liquid Chromatography coupled with High-Resolution Mass Spectrometry (nano-LC/HRMS). The results indicated that SS treatment accelerated the glycosylation process, reduced free amino groups level, and distinguished their unique flavor through E-nose. GC-IMS analysis detected 64 signal peaks including 13 aldehydes, 6 ketones, 7 esters, 6 alcohols, 2 acids, 2 furans and 5 other substances. And it was revealed that SS-mediated glycosylation treatment reduced the levels of fishy odorants like Heptanal and Nonanal, while promoting the pleasant-smelling alcohols and esters. In addition, Pearson correlation showed a positive correlation between excessive glycation and the increase in aldehydes, which might cause the recurrence of undesirable fishy notes. Further nano-LC/HRMS analysis revealed that arginine and lysine acted as the main sites for glycosylation modification. Notably, glycosylated peptides such as KAFGHENEALVRK, DSRAATSPGELGVTIEGPKE, generated by mild SS treatment could convert into ketones and pyrazines in subsequent reactions, thereby contributing to overall sensory enhancement. In conclusion, SS treatment at 110 °C for 1 min significantly improved the flavor quality of OP and sustains improvement in subsequent stages, providing theoretical support for flavor optimization of oyster peptides. Full article

Parkinson’s disease (PD) is a progressive neurodegenerative disorder primarily characterized by the degeneration of dopaminergic neurons, leading to significant motor and non-motor symptoms. This study investigates glycosylation patterns with a significant emphasis on male Parkinson’s Disease (PD) patients, revealing unique alterations distinguishing PD from healthy states, utilizing high-performance liquid chromatography coupled with mass spectrometry (HILIC-LC-MS). Findings reveal significantly altered serum N-glycosylation profiles between male and female patients, with increased levels of high-mannose glycans and reduced mono-sialylated glycans in male patients. ROC curve analysis indicates that these glycan changes are the most important features for distinguishing PD from healthy states, with AUC values of 0.71 for M5 and 0.85 for M6. This study underscores the critical role of glycosylation in the pathophysiology of Parkinson’s disease and highlights its potential in early detection and monitoring of disease progression. Full article