In order to investigate the relationship between the function of a native glycoprotein and the structure of a sugar chain, it is important to obtain a protein that has a homogeneous glycan structure. Enzymatic methods using glycosyltransferases and glycoside hydrolases and organic chemical methods to achieve this are well established. Besides, methods utilizing sugar chains present in natural products have also been explored. In this mini review, the extraction, purification, and preparation of N-glycan from natural products (chicken eggs, edible bird’s nest, gingko nuts, and soybeans), from which the yields of the homogeneous glycans are easily available, are described in detail.

Although ABO blood group antigens are widely distributed on the surface of red blood cells and epithelial cells, and in secreted body fluids, the biological function of these antigens is not clearly elucidated. Von Willebrand factor (VWF), the molecular glue between platelets and injured vessels essential for the formation of thrombotic plugs, may shed a light on their function. VWF is a unique plasma protein carrying ABO blood group antigens. Blood group influences the plasma concentration of VWF, and its level in those of blood group O is about 25% less than in non-O groups. Blood group O individuals are less sensitive to thrombotic disorders such as cardiovascular disease than non-O individuals. However, among those of blood group O, there is a significant association with high mortality in severe trauma patients. The sensitivity of VWF toward ADAMTS13, a physiological VWF-cleaving proteinase in plasma, is higher in those of blood group O, suggesting the protective role of blood group sugar chains. Although the capping sialic acid residue of plasma glycoprotein has been considered as a negatively charged barrier to hydrolyzing enzymes such as proteinase, and the penultimate galactose residue, once exposed, functions as a clearance marker for asialo-glycoprotein receptor, ABO blood group sugar chains on VWF may function as a neutral sugar chain barrier protecting the glycoprotein.

The pathogenesis of depression remains unclear. Present diagnostic criteria for depression does not include any biological aspects. Although various serum and plasma proteins, such as neurotrophic factors and cytokines have been reported as candidate biomarkers of depression, these proteins have been analyzed only quantitatively. Moreover, a few clinical studies have been reported which consider glycosylation analysis in depression. Furthermore, a very few basic research work focus on analyzing glycans in case of depression. In this article, we review the recent findings in glycobiology, highlighting its potential as a biological marker of depression.

N- and O-arylated carbohydrates except for aryl glycosides are not found in nature. Therefore, based on their structure, these derivatives are expected as new functional molecules. However, the synthesis of arylated carbohydrates has not been thoroughly investigated and few studies have been reported their application. Hence, our research focused on the elucidation of the arylated carbohydrates function. Various N-arylated carbohydrates were synthesized using the Buchwald-Hartwig reaction, while O-arylated carbohydrates were obtained by employing hypervalent iodine reagents. Based on these compounds, we succeeded in developing novel fluorescently labeled glucose derivatives, aryl-based protecting groups, and a stereoselective glycosylation.

Glycosaminoglycans (GAGs), a group of structurally related acidic polysaccharides, are primarily present as glycan moieties of proteoglycans (PGs). The physiological functions of PGs depend on the interaction between the glycan moieties and proteins such as growth factors, chemokines, and adhesion molecules. For this reason, the sulfation pattern, the degree of epimerization, and the glycan moiety chain length impact their interactions with GAG-binding proteins. Although the structural changes in GAGs occur during the development and aging process, their detailed mechanisms are not fully understood. This review provides an overview of the heparan sulfate (HS)- and chondroitin sulfate (CS)-related gene expression at the transcriptional and translational level. In addition, it also describes the molecular mechanisms of the polyamine stimulation of glycosaminoglycan synthesis.

In order to investigate the relationship between the function of a native glycoprotein and the structure of a sugar chain, it is important to obtain a protein that has a homogeneous glycan structure. Enzymatic methods using glycosyltransferases and glycoside hydrolases and organic chemical methods to achieve this are well established. Besides, methods utilizing sugar chains present in natural products have also been explored. In this mini review, the extraction, purification, and preparation of N-glycan from natural products (chicken eggs, edible bird’s nest, gingko nuts, and soybeans), from which the yields of the homogeneous glycans are easily available, are described in detail.

Although ABO blood group antigens are widely distributed on the surface of red blood cells and epithelial cells, and in secreted body fluids, the biological function of these antigens is not clearly elucidated. Von Willebrand factor (VWF), the molecular glue between platelets and injured vessels essential for the formation of thrombotic plugs, may shed a light on their function. VWF is a unique plasma protein carrying ABO blood group antigens. Blood group influences the plasma concentration of VWF, and its level in those of blood group O is about 25% less than in non-O groups. Blood group O individuals are less sensitive to thrombotic disorders such as cardiovascular disease than non-O individuals. However, among those of blood group O, there is a significant association with high mortality in severe trauma patients. The sensitivity of VWF toward ADAMTS13, a physiological VWF-cleaving proteinase in plasma, is higher in those of blood group O, suggesting the protective role of blood group sugar chains. Although the capping sialic acid residue of plasma glycoprotein has been considered as a negatively charged barrier to hydrolyzing enzymes such as proteinase, and the penultimate galactose residue, once exposed, functions as a clearance marker for asialo-glycoprotein receptor, ABO blood group sugar chains on VWF may function as a neutral sugar chain barrier protecting the glycoprotein.

The pathogenesis of depression remains unclear. Present diagnostic criteria for depression does not include any biological aspects. Although various serum and plasma proteins, such as neurotrophic factors and cytokines have been reported as candidate biomarkers of depression, these proteins have been analyzed only quantitatively. Moreover, a few clinical studies have been reported which consider glycosylation analysis in depression. Furthermore, a very few basic research work focus on analyzing glycans in case of depression. In this article, we review the recent findings in glycobiology, highlighting its potential as a biological marker of depression.

N- and O-arylated carbohydrates except for aryl glycosides are not found in nature. Therefore, based on their structure, these derivatives are expected as new functional molecules. However, the synthesis of arylated carbohydrates has not been thoroughly investigated and few studies have been reported their application. Hence, our research focused on the elucidation of the arylated carbohydrates function. Various N-arylated carbohydrates were synthesized using the Buchwald-Hartwig reaction, while O-arylated carbohydrates were obtained by employing hypervalent iodine reagents. Based on these compounds, we succeeded in developing novel fluorescently labeled glucose derivatives, aryl-based protecting groups, and a stereoselective glycosylation.

Glycosaminoglycans (GAGs), a group of structurally related acidic polysaccharides, are primarily present as glycan moieties of proteoglycans (PGs). The physiological functions of PGs depend on the interaction between the glycan moieties and proteins such as growth factors, chemokines, and adhesion molecules. For this reason, the sulfation pattern, the degree of epimerization, and the glycan moiety chain length impact their interactions with GAG-binding proteins. Although the structural changes in GAGs occur during the development and aging process, their detailed mechanisms are not fully understood. This review provides an overview of the heparan sulfate (HS)- and chondroitin sulfate (CS)-related gene expression at the transcriptional and translational level. In addition, it also describes the molecular mechanisms of the polyamine stimulation of glycosaminoglycan synthesis.