Insights into the history and tendency of glycosylation and digestive system tumor:A bibliometric-based visual analysis

BACKGROUND Glycosylation,a commonly occurring post-translational modification,is highly expressed in several tumors,specifically in those of the digestive system,and plays a role in various cellular pathophysiological mechanisms.Although the importance and detection methods of glycosylation in digestive system tumors have garnered increasing attention in recent years,bibliometric analysis of this field remains scarce.The present study aims to identify the developmental trends and research hotspots of glycosylation in digestive system tumors.AIM To find and identify the developmental trends and research hotspots of glycosylation in digestive system tumors.METHODS We obtained relevant literature from the Web of Science Core Collection and employed VOSviewer 1.6.19 and CiteSpace(version 6.1.R6)to perform bibliometric analysis.RESULTS A total of 2042 documents spanning from 1978 to the present were analyzed,with the research process divided into three phases:the period of obscurity(1978-1990),continuous development period(1991-2006),and the rapid outbreak period(2007-2023).These documents were authored by researchers from 66 countries or regions,with the United States and China leading in terms of publication output.Reis Celso A had the highest number of publications,while Pinho SS was the most cited author.Co-occurrence analysis revealed the most popular keywords in this field are glycosylation,expression,cancer,colorectal cancer,and pancreatic cancer.Furthermore,the Journal of Proteome Research was the most prolific journal in terms of publications,while the Journal of Biological Chemistry had the most citations.CONCLUSION The bibliometric analysis shows current research focus is primarily on basic research in this field.However,future research should aim to utilize glycosylation as a target for treating tumor patients.

Preparation,characterization and antioxidant activity analysis of three Maillard glycosylated bone collagen hydrolysates from chicken,porcine and bovine

Bone collagen hydrolysates(peptides)derived from byproduct of animal product processing have been used to produce commercially valuable products due to their potential antioxidant activity.Maillard glycosylated reaction is considered as a promising method to enhance the antioxidant activity of peptides.Hence,this research aims at investigating the Maillard glycosylation activity and antioxidant activity of bone collagen hydrolysates from different sources.In this study,3 glycosylated bone collagen hydrolysates were prepared and characterized,and cytotoxicity and antioxidant activity were analyzed and evaluated.The free amino groups loss,browning intensity,and fluorescence intensity of G-Cbcp(glycosylated chicken bone collagen hydrolysates(peptides))were the heaviest,followed by G-Pbcp(glycosylated porcine bone collagen hydrolysates(peptides))and G-Bbcp(glycosylated bovine bone collagen hydrolysates(peptides)).The results of amino acid analysis showed that amino acid composition of different bone collagen hydrolysates was significantly different and the amino acid decreased to different degrees after Maillard glycosylated reaction,which may lead to differences in Maillard glycosylated reaction activity.Furthermore,the 3 glycosylated hydrolysates showed no significant cytotoxicity.The results showed that glycosylation process significantly increased the antioxidant activity of bone collagen hydrolysates,and G-Cbcp showed the strongest antioxidant activity,followed by G-Pbcp and G-Bbcp.Therefore,compared with the bone collagen hydrolysates,3 glycosylated hydrolysates showed significant characteristic and structural changes,and higher antioxidant activity.

Effect of Glycosylation on the Physicochemical Properties,Structure and Iron Bioavailability of Ferritin Extracted from Tegillarca granosa

Iron deficiency anemia(IDA)is a major global health problem.Tegillarca granosa has been considered as an excellent source of iron given its high content of iron-binding protein,ferritin.The aim of the present study was to determine the physicochemical properties,protein structures,and iron uptake of ferritin extracted from T.granosa,and to evaluate the potential impacts of chitosan glycosylation on these characteristics.Based on Box-Behnken design and response surface methodology,the optimal conditions for glycosylation included a ferritin/chitosan mass ratio of 4:1,a pH of 5.5,a reaction time of 10 min,and a reaction temperature of 50℃.Glycosylation caused decreased surface hydrophobicity and elevated water-holding capacity of ferritin due to the introduction of hydrophilic groups.Additionally,glycosylation improved antioxidant capacity of ferritin by 20.69%–189.66%,likely owing to the protons donated by saccharide moiety to terminate free radical chain reaction.The in vitro digestibility of ferritin was elevated by 22.56%–104.85%after glycosylation,which could be associated with lessβ-sheet content in secondary structure that made the glycosylated protein less resistant to enzymatic digestion.The results of the iron bioavailability in Caco-2 cells revealed that ferritin(78.85–231.77 ngmg^(−1))exhibited better iron bioavailability than FeSO4(51.48–114.37 ngmg^(−1))and the values were further elevated by glycosylation with chitosan(296.23–358.20 ngmg^(−1)),which may be related to the physicochemical properties of ferritin via glycosylation modification.These results provide a basis for the development of T.granosa derived ferritin and its glycosylated products,and can promote the utilization of aquatic resources.

Glycosyltransferases and non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease(NAFLD) is the most common form of chronic liver disease and its incidence is increasing worldwide. However, the underlying mechanisms leading to the development of NAFLD are still not fully understood. Glycosyltransferases(GTs) are a diverse class of enzymes involved in catalyzing the transfer of one or multiple sugar residues to a wide range of acceptor molecules. GTs mediate a wide range of functions from structure and storage to signaling, and play a key role in many fundamental biological processes. Therefore, it is anticipated that GTs have a role in the pathogenesis of NAFLD. In this article, we present an overview of the basic information on NAFLD, particularly GTs and glycosylation modification of certain molecules and their association with NAFLD pathogenesis. In addition, the effects and mechanisms of some GTs in the development of NAFLD are summarized.

Thionization Method of Glycosyl Urea and Carbamide Sugars

This work is describing a thionization method for glycosyl urea and carbamide of sugars by using the Lawesson’s reagent. It is proposed the method based on the interaction of glycosyl urea and carbamide of sugars with the Lawessons reagent at a 1:1 ratio in the presence of a pyridine. As a result, sulfur-containing derivatives of sugar carbamides are obtained with the help of Lawesson’s reagent. Obtained experimental data are indicating the developed new method for thionization of sugar carbamides, which opens up broad possibilities for synthesis of various carbohydrate derivatives of thiourea. Significance of this work is that, thiourea derivatives are promising bactericidal, fungicidal and anti-inflammatory drugs. Therefore, the preparation of thiourea derivatives and the study of their properties remain topical tasks in the field of chemistry.

The Purification of Glucose Type Glycosyl Nitrate and the Synthesis of Spacer-armed N-Acetyllactosamines and Their Dimers

di-O-acetyl-4-O-(2, 3, 4, 6-tetra-O-acetyl-b-D-galactopyranosyl)-2-azido-2-deoxy- b-D-glucoppyranosyl nitrate could be separated from its mannose type isomer by glycosylation according to the reactivity difference of these two compounds. The pure glucose type nitrate can be converted to corresponding trichloroacemidate, which reacted with spacer arms in solution of CH2Cl2 with BF3稥t2O as promoters to give desired glycosides and dimers.

Description of a Putative Oligosaccharyl:S-Layer Protein Transferase from the Tyrosine <i>O</i>-Glycosylation System of <i>Paenibacillus alvei</i>CCM 2051^T

Surface (S)-layer proteins are model systems for studying protein glycosylation in bacteria and simultaneously hold promises for the design of novel, glyco-functionalized modules for nanobiotechnology due to their 2D self-assembly capability. Understanding the mechanism governing S-layer glycan biosynthesis in the Gram-positive bacterium Paenibacillus alvei CCM 2051T is necessary for the tailored glyco-functionalization of its S-layer. Here, the putative oligosaccharyl:S-layer protein transferase WsfB from the P. alvei S-layer glycosylation gene locus is characterized. The enzyme is proposed to catalyze the final step of the glycosylation pathway, transferring the elongated S-layer glycan onto distinct tyrosine O-glycosylation sites. Genetic knock-out of WsfB is shown to abolish glycosylation of the S-layer protein SpaA but not that of other glycoproteins present in P. alvei CCM 2051T, confining its role to the S-layer glycosylation pathway. A transmembrane topology model of the 781-amino acid WsfB protein is inferred from activity measurements of green fluorescent protein and phosphatase A fused to defined truncations of WsfB. This model shows an overall number of 13 membrane spanning helices with the Wzy_C domain characteristic of O-oligosaccharyl:protein transferases (O-OTases) located in a central extra-cytoplasmic loop, which both compares well to the topology of OTases from Gram-negative bacteria. Mutations in the Wzy C motif resulted in loss of WsfB function evidenced in reconstitution experiments in P. alvei ΔWsfB cells. Attempts to use WsfB for transferring heterologous oligosaccharides to its native S-layer target protein in Escherichia coli CWG702 and Salmonella enterica SL3749, which should provide lipid-linked oligosaccharide substrates mimicking to some extent those of the natural host, were not successful, possibly due to the stringent function of WsfB. Concluding, WsfB has all features of a bacterial O-OTase, making it the most probable candidate for the oligosaccharyl:S-layer protein transferase of P. alvei, and a promising candidate for the first O-OTase reported in Gram-positives.

Design and Synthesis of Glycosylated Aromatic Nitrogen Mustard Derivatives

Antibody-directed enzyme prodrug therapy（ADEPT） is a new strategy for the treatment of cancer that has arisen in recent twenty years, the main merits of which are that it can improve the selectivity of anticancer drugs and reduce the side effects in remote tissue. In the present study, two prodrugs-glycosylated aromatic nitrogen mustard derivatives were synthesized. Glucose and lactose were converted into glycosyl donors-trichloroacetimidate; the obtained glycosyl donors were glycosylated with p-nitrophenol （ glycosyl donors） to form β-glucosyl p-nitrobenzene and β-lactosyl p-nitrobenzene that were protected by acetyl in a stereoselective manner; the two products were reduced by zinc dust and then treated with ethylene oxide, afforded two glycosylated nitrogen mustard derivatives that were protected by acetyl; the last step was to deacetylate and then afforded the two target compounds that could be used as prodrugs of ADEPT for further Anti-tumor research.

Aberrant glycosylation of the anti-Thomsen-Friedenreich glycotope immunoglobulin G in gastric cancer patients

AIM: To study whether alterations in the glycosylation of immunoglobulin G (IgG) specific to the ThomsenFriedenreich glycotope (TF) have diagnostic and prognostic potential in gastric cancer. METHODS: Serum samples were obtained from patients with histologically verified gastric carcinoma (n = 89), healthy blood donors (n = 40), and patients with benign stomach diseases (n = 22). The lectin-enzymelinked immunosorbent assay-based glycoprofiling of TF-specific IgG (anti-TF IgG) was performed using synthetic TF-polyacrylamide conjugate as antigen, total IgG purified by affinity chromatography on protein G sepharose, and lectins of various sugar specificities: mannose-specific concanavalin A (ConA), fucose-specificAleuria aurantia lectin (AAL) and sialic acid-specific Sambucus nigra agglutinin (SNA). The sensitivity and specificity of the differences between cancer patients and controls were evaluated by receiver operator characteristic (ROC) curve analysis. Overall survival was analyzed by the Kaplan-Meier method. Time-dependent ROC curve statistics were applied to determine cut-off values for survival analysis. All calculations and comparisons were performed using the GraphPad Prism 5 and SPSS 15.0 software.RESULTS: The level of TF-specific IgG was significantly increased in cancer patients compared with non-cancer controls (P < 0.001). This increase was pronounced mostly in stage 1 of the disease. Cancer patients showed a higher level of ConA binding to antiTF-IgG (P < 0.05) and a very low level of SNA lectin binding (P = 0.0001). No appreciable stage-dependency of the binding of any lectin to anti-TF IgG was found. A strong positive correlation between the binding of AAL and SNA was found in all groups studied (r = 0.71-0.72; P < 0.0001). The changes in ConA reactivity were not related to those of the fucoseor sialic acid-specific lectin. Changes in the SNA binding index and the ConA/SNA binding ratio demonstrated good sensitivity and specificity for stomach cancer: sensitivity 78.79% (95%CI: 61.09-91.02) and 72.73% (95%CI: 57.21-85.04); specificity 79.17 (95%CI: 65.01-89.53) and 88.64% (95%CI: 71.8-96.6), for the SNA binding index and the ConA/SNA binding ratio, respectively. The other combinations of lectins did not improve the accuracy of the assay. The low level of ConA-positive anti-TF IgG was associated with a survival benefit in cancer patients (HR = 1.56; 95%CI: 0.78-3.09; P = 0.19), especially in stages 3-4 of the disease (HR = 2.17; 95%CI: 0.98-4.79; P = 0.048). A significantly better survival rate was found in all cancer patients with a low reactivity of anti-TF IgG to the fucose-specific AAL lectin (HR = 2.39; 95%CI: 1.0-5.7;P = 0.038).CONCLUSION: The changes in the TF-specific IgG glycosylation pattern can be used as a biomarker for stomach cancer detection, and to predict patient survival.

Inhibition of KL-6/MUC1 glycosylation limits aggressive progression of pancreatic cancer

AIM:To evaluate the significance of KL-6/MUC1(a type of MUC1)glycosylation in pancreatic cancer progression.METHODS:KL-6/MUC1 expression was detected by immunohistochemistry in 48 patients with pancreatic duct cell carcinoma.The N-/O-glycosylation inhibitors(tunicamycin and benzyl-N-acetyl-α-galactosaminide)were then used to interfere with KL-6/MUC1 glycosylation in two pancreatic carcinoma cell lines,and the effects on KL-6/MUC1 expression,and cell adhesion and invasion were determined.In addition,protein expression of epithelial-mesenchymal transition markers,E-cadherin and vimentin,were evaluated in cells after treatment with glycosylation inhibitors.RESULTS:Overexpression of KL-6/MUC1 was found in all pancreatic cancer tissues,but not in the surrounding normal pancreatic tissues.The expression profile of KL-6/MUC1 was significantly decreased after treatment with the inhibitors.The adhesion and invasive ability of cancer cells were significantly decreased after drug treatment,and increased E-cadherin and decreased vimentin expression were found.CONCLUSION:KL-6/MUC1 glycosylation is involved in pancreatic cancer metastasis and invasion.Therapeutic strategies which target this may help control the aggressive behavior of pancreatic cancer cells.

Role of serum β2-microglobulin, glycosylated hemoglobin, and vascular endothelial growth factor levels in diabetic nephropathy

BACKGROUND Diabetic nephropathy(DN)is a common complication of type 1 and type 2 diabetes that can lead to kidney damage and high blood pressure.Increasing evidence support the important roles of microproteins and cytokines,such asβ2-microglobulin(β2-MG),glycosylated hemoglobin(HbA1c),and vascular endothelial growth factor(VEGF),in the pathogenesis of this disease.In this study,we identified novel therapeutic options for this disease.AIM To analyze the guiding significance ofβ2-MG,HbA1c,and VEGF levels in patients with DN.METHODS A total of 107 patients with type 2 diabetes mellitus complicated with nephropathy and treated in our hospital from May 2018 to February 2021 were included in the study.Additionally,107 healthy individuals and 107 patients with simple diabetes mellitus were selected as the control groups.Changes inβ2-MG,HbA1c,and VEGF levels in the three groups as well as the different proteinuria exhibited by the three groups were examined.RESULTS Changes inβ2-MG,HbA1c,and VEGF levels in the disease,healthy,and simple diabetes groups were significantly different(P<0.05).The expression of these factors from high to low were evaluated in different groups by pairwise comparison.In the disease group,high to low changes inβ2-MG,HbA1c,and VEGF levels were noted in the massive proteinuria,microproteinuria,and normal urinary protein groups,respectively.Changes in these factors were positively correlated with disease progression.CONCLUSION The expression of serumβ2-MG,HbA1c,and VEGF was closely correlated with DN progression,and disease progression could be evaluated by these factors.

Glycosylation of the hemagglutinin protein of H9N2 subtype avian influenza virus influences its replication and virulence in mice

N-Linked glycosylation of hemagglutinin(HA) has been demonstrated to regulate the virulence and receptor-binding specificity of avian influenza virus(AIV).In this study,we characterized the variation trend of naturally isolated H9 N2 viruses for the potential N-linked glycosylation sites in HA proteins,and explored any important role of some glycosylation sites.HA genes of 19 H9 N2 subtype AIV strains since 2001 were sequenced and analyzed for the potential glycosylation sites.The results showed that the viruses varied by losing one potential glycosylation site at residues 200 to 202,and having an additional one at residues 295 to 297 over the past few years.Further molecular and single mutation analysis revealed that the N200 Q mutation lost an N-linked glycosylation at positions 200 to 202 of the HA protein and affected the human-derived receptor affinity.We further found that this N-linked glycosylation increased viral productivity in the lung of the infected mice.These findings provide a novel insight on understanding the determinants of host adaption and virulence of H9 N2 viruses in mammals.

Structural and functional properties of hydrolyzed/glycosylated ovalbumin under spray drying and microwave freeze drying

Ovalbumin(OVA),the main protein in egg white,affects most of the functional properties of egg white protein in food processing.The aim of this study was to investigate the effects of spray drying(SD)and microwave freeze drying(MFD)on the preparation of hydrolyzed/glycosylated ovalbumin(HGOVA)and provide useful information on the applications of egg protein powders in the food industry.Results demonstrated that the structure of HGOVA was considerably changed,and its functional properties were improved compared with those of native OVA.SD and MFD processing did not lead to dissociation of HGOVA subunits.SD-HGOVA exhibited higher protein solubility,emulsifying activity,foaming capacities,and gel hardness than MFD-HGOVA.However,MFD-HGOVA was better than the SD-HGOVA in terms of color,emulsion stability,foam stability,water/oil absorption capacity,and thermal stability.Selection of an appropriate drying method could enhance the potential applications of HGOVA in the food industry.

Synthesis of (±)-Demethylnitidanin, Herpetol and Salvinal as well as Their Glycosyl Derivatives

Three neolignans, （±）-demethylnitidanin（1）, herpetol（2） and salvinal（3） were synthesized from methyl 4,5-dihydroxy-3-methoxy cinnamate or methyl 4-hydroxy-3-methoxy cinnamate with Ag2O-catalyzed biomimetic oxidative coupling as the key step of the synthetic route. Five novel benzofuran neolignan-4＇-O-β-D-glycosides（4―8） were achieved by the glycosylation reactions of benzofuran neolignans 2, 3 and 15. The structures of all the compounds synthesized were determined by MS, 1H NMR and IR spectra. （±）-Demethylnitidanin（1） and herpetol（2） were the first synthesized and the synthesis of salvinal（3） was efficiently improved by the new synthetic routes.

Serum Mac-2 binding protein glycosylation isomer level predicts hepatocellular carcinoma development in E-negative chronic hepatitis B patients

BACKGROUND Liver cirrhosis is a major risk factor for hepatocellular carcinoma(HCC)development in chronic hepatitis B(CHB). Serum Mac-2 binding protein glycosylation isomer(M2 BPGi) is a novel serological marker for fibrosis. The role of M2 BPGi in prediction of HCC is unknown.AIM To examine the role of serum M2 BPGi in predicting HCC development in hepatitis B e antigen(HBeAg)-negative patients.METHODS Treatment-naive CHB patients with documented spontaneous HBeAg seroconversion were recruited. Serum M2 BPGi was measured at baseline(within3 years from HBeAg seroconversion), at 5 years and 10 years after HBeAg seroconversion and expressed as cut-off index(COI). Multivariate cox regression was performed to identify predictors for HCC development. ROC analysis was used to determine the cut-off value of M2 BPGi.RESULTS Among 207 patients(57% male, median age at HBeAg seroconversion 40 years old) with median follow-up of 13.1(11.8-15.5) years, the cumulative incidence of HCC at 15 years was 7%. Median M2 BPGi levels were significantly higher in patients with HCC compared to those without HCC(baseline: 1.39 COI vs 0.38 COI, P < 0.001; 5-year: 1.45 COI vs 0.47 COI, P < 0.001; 10-year: 1.20 COI vs 0.55 COI, P = 0.001). Multivariate analysis revealed age at HBeAg seroconversion[odds ratio(OR) = 1.196, 95% confidence interval(CI): 1.034-1.382, P = 0.016] and baseline M2 BPGi(OR = 4.666, 95%CI: 1.296-16.802, P = 0.018) were significant factors predictive of HCC. Using a cut-off value of 0.68 COI, baseline M2 BPGi yielded AUROC of 0.883 with 91.7% sensitivity and 80.8% specificity.CONCLUSION High serum M2 BPGi within 3 years after HBeAg seroconversion was a strong predictor for subsequent HCC development in treatment-naive HBeAg-negative CHB patients.

Novel Catalytic Method for Synthesis of Glycosyl Esters by Combining PTC with DMAP

This article presents a novel catalytic method by combining phase-transfer catalyst, benzyltriethylammonium chloride, with 4-dimethylaminopyridine for the syntheses of glycosyl esters from substituted phenoxyaeetie acids and the peracetate of α-D-l-bromosugars to produee eight novel β-glyeosyl esters in high yields. The struetures of the syn-thesized eompounds were established by IR, MS, ^1H NMR, and ^13C NMR speetra and elemental analyses.

Symplocosionosides A-C, Three Megastigmane Glycosides, a Neolignan Glucoside, and Symplocosins A and B, Two Triterpene Glycosyl Esters from the Leaves of <i>Symplocos cochinchinensis</i>var. <i>Philippinensis</i>

From the 1-BuOH-soluble fraction of a MeOH extract of the leaves of Symplocos cochinchinensis var. philippinensis, 12 compounds were isolated. Spectroscopic analyses of compounds 1 - 3 established their structures to be megastig-mane glycosides, named symplocosionosides A-C. The absolute structure of 1 was determined by the modified Mosher’s method. Compound 4 was found to be a neolignan glucoside and named symplocosneolignan. The structures of com-pounds 5 and 6, named symplocosins A and B, were elucidated to be the saponins of hederagenin sugar esters. The structures of the remaining known compounds (7 - 12) were identified by comparison of spectroscopic data with those reported in the literature.

O-linked N-acetylglucosamine transferase(OGT) is overexpressed and promotes O-linked protein glycosylation in esophageal squamous cell carcinoma

The aim of this present study was to explore the expression and clinical significance of O-linked N-acetylglucosamine（O-GlcNAc） transferase（OGT） and enzymatic O-linked glycosylation（O-GlcNAcation） through the addition of O-linked-β-N-acetylglucosamine in esophageal squamous cell carcinoma.OGT expression and O-GlcNAcation in 40 samples from patients with esophageal squamous cell carcinoma was detected by immunohistochemical staining with anti-OGT antib ody and O-GlcNAc-specific antibody RL 2,respectively.The relationship between pathological and clinical factors of patients was analyzed.We found that the expression of OGT was higher in esophageal squamous cell carcinoma samples compared to the normal tissues.RL 2 antibody level was positively correlated with OGT expression,and the metastasis of lymph node,which means the level of O-GlcNAcation was high and related to the metastasis of lymph node in esophageal squamous cell carcinoma.In conclusion,OGT activation is the main reason for promoting the level of O-GlcNAcation in esophageal squamous cell carcinoma.O-GlcNAcylation may play an important role in esophageal squamous cell carcinoma.

INTERACTION BETWEEN THE SURFACE GLYCOSYLATED POLYPROPYLENE MEMBRANE AND LECTIN

A glycopolymer bearing glucose residues was tethered onto the surface of polypropylene microporous membrane by UV-induced graft polymerization ofα-allyl glucoside.Concanavalin A (Con A),a glucose recognizing lectin,could be specifically adsorbed to the membrane surface.On the other hand,the membrane surface showed no recognition ability to another lectin peanut agglutinin.Moreover,the recognition complex between the glycosylated membrane surface and Con A could be inhibited by glucose and mannose solution.T...

Unraveling GLUT-mediated transcytosis pathway of glycosylated nanodisks

Glucose transporter(GLUT)-mediated transcytosis has been validated as an efficient method to cross the blood-brain barrier and enhance brain transport of nanomedicines.However,the transcytosis process remains elusive.Glycopeptide-modified nanodisks(Gly-A7R-NDs),which demonstrated high capacity of brain targeting via GLUT-mediated transcytosis in our previous reports,were utilized to better understand the whole transcytosis process.Gly-A7R-NDs internalized brain capillary endothelial cells mainly via GLUT-mediated/clathrin dependent endocytosis and macropinocytosis.The intracellular Gly-A7R-NDs remained intact,and the main excretion route of Gly-A7R-NDs was lysosomal exocytosis.Glycosylation of nanomedicine was crucial in GLUT-mediated transcytosis,while morphology did not affect the efficiency.This study highlights the pivotal roles of lysosomal exocytosis in the process of GLUT-mediated transcytosis,providing a new impetus to development of brain targeting drug delivery by accelerating lysosomal exocytosis.