Carbohydrate Research最新文献

Streptococcus agalactiae or Group B Streptococcus (GBS) is a major causative agent of neonatal sepsis, meningitis, still births and postnatal complications in women. Capsular polysaccharides (CPS) on the bacterial surface are implicated in pathogen virulence by evasion of host cellular defense mechanisms and have in turn served as attractive vaccine candidates for maternal immunization. In this study, we probed the role of a key structural feature, N-acetylation of constituent sugars in GBS capsular polysaccharide, on product characteristics and preclinical immunogenicity. Loss of N-acetyl groups in CPS during the purification stage requires a re-N-acetylation step to restore the N-acetylation levels in the polysaccharide. GBS serotype (ST) III CPS with different % N-acetylation levels were prepared and utilized for conjugate vaccine preparation involving rCRM197 as a carrier protein and subjected to structural and analytical characterization and immunogenicity evaluation in rabbits. Although different levels of re-N-acetylation in CPS as determined by proton NMR did not impact glycoconjugate stability, serological analysis revealed strong and direct correlation of N-acetylation levels in the CPS to the quality of neutralizing (IgG) and functional antibody responses to the GBS III vaccine. Collectively, the study findings suggest N-acetylation to be a salient structural feature and part of the immunodominant epitope in GBS CPS that defines the critical product attributes dictating vaccine quality and immunogenicity.

Chondroitin sulfate (CS)-based nanozymes have emerged as promising alternatives to natural enzymes for catalytic biomaterial fabrication. In this work, a hemin-functionalized chondroitin sulfate conjugate (CS-His-He) was developed as a peroxidase-mimicking catalyst for the oxidative crosslinking of tyramine-modified gelatin (Gel-Tyr), enabling in situ hydrogel formation under physiologically relevant conditions. The CS-His-He nanozyme efficiently catalyzed phenolic coupling reactions in the presence of hydrogen peroxide, producing Gel-Tyr hydrogels with physicochemical properties comparable to those obtained using horseradish peroxidase (HRP). The resulting hydrogels exhibited rapid gelation, stable network formation, and good hydrolytic stability, retaining approximately 73-75 wt% of their initial mass after 48 h under enzyme-free conditions. In the presence of collagenase, both hydrogel systems underwent rapid enzymatic degradation, with residual masses of about 23-20 wt% after 48 h, confirming their enzyme-responsive degradability. Cytocompatibility studies using human dermal fibroblasts showed high cellular metabolic activity (>95%) and normal cell morphology. Overall, the CS-His-He nanozyme effectively replaces HRP for Gel-Tyr hydrogel formation while maintaining comparable physicochemical properties, enzymatic degradability, and cytocompatibility, highlighting its potential as a robust catalytic platform for injectable biomaterials and enzyme-responsive hydrogel systems.

Digestive glucosidases are targets of anti-hyperglycemic agents used in the treatment of diabetes. Previously, our group synthetized a novel 2-phenyl-2H-1,2,3-triazole-oxime (compound 7) with α-amylase inhibitory activity. Here, we report the acute in vivo antihyperglycemic effect of compound 7 in a murine model and evaluate its drug metabolism and pharmacokinetic (DMPK) properties. At 10 mg/kg, compound 7 reduced peak blood glucose levels by 29% following oral administration of 4 g/kg maltose, with a response comparable to acarbose (38.2%), a clinically approved α-glucosidase inhibitor widely used as a reference compound. In contrast, a significant 22.1% decrease in blood glucose was observed only 120 min after starch administration (4 g/kg). The compound exhibits significant cellular permeability in the MDCK cell assay, good aqueous solubility, and undergoes rapid microsomal hepatic metabolism. In summary, we have further characterized the biological properties of an easily synthesizable non-glycosidic compound and discussed its potential as a lead compound for the treatment of diabetes considering its unconventional DMPK profile. Further studies are needed to better characterize the antihyperglycemic activity of compound 7.

Lectins play crucial roles in various biological processes, such as cell-cell recognition, immune responses, and pathogen infections, through the specific recognition of sugar chain structures. Therefore, elucidating lectin-sugar chain interactions is essential for understanding their physiological and pathological functions. Previously, we developed sugar chain-immobilized metal nanoparticles as tools for analyzing lectin-sugar chain interactions and isolating lectins. These nanoparticles aggregate with lectins possessing multiple subunits with sugar chain-binding sites, thereby facilitating the analysis and isolation of lectins. However, this approach is not applicable to lectins that do not induce aggregation, such as single-subunit lectins. To address this limitation, we established a lectin pull-down method employing biotin-labeled sugar chain-immobilized gold nanoparticles and streptavidin-functionalized magnetic beads. This technique enables effective analysis of sugar chain interactions involving both monomeric and multimeric lectins. The method has also been demonstrated to capture lectins from complex biological samples, such as serum and tissue homogenate. Thus, this lectin pull-down is a valuable approach for studying lectin-sugar chain interactions and offers potential for lectin isolation from biological samples.

Colorectal cancer is the third most common cancer worldwide and the second leading cause of cancer-related mortality. In 2020 alone, over 1.9 million new cases and 935,000 deaths were reported. Despite advancements in therapy, there remains a strong need for targeted and less toxic treatment approaches. Fucoidan, a sulfated polysaccharide derived from brown seaweeds, exhibits notable anti-inflammatory, antioxidant, and anticancer properties. Researchers have explored fucoidan-based nanoparticles to improve its solubility, enhance tumor-targeting efficiency, and expand its therapeutic potential. This review highlights the dual functional role of fucoidan-functionalized nanoparticles in colorectal cancer therapy. Fucoidan acts both as a targeted delivery carrier for colon-specific drug release and as an intrinsic antineoplastic agent. It recognizes tumor cells through P-selectin-mediated and receptor-specific pathways, facilitating improved targeting. Additionally, fucoidan induces cancer cell apoptosis, suppresses angiogenesis, and modulates immune responses. When combined with chemotherapeutics, siRNA, or immunomodulators, fucoidan nanoparticles exhibit synergistic anticancer effects while minimizing systemic toxicity. However, translational progress remains limited due to variability in fucoidan composition, lack of standardized characterization methods, and regulatory challenges. Addressing these issues is essential to advance fucoidan-based nanotherapeutics toward clinical application.

This review aims to discuss the dynamic applications of carrageenan in the field of nanotechnology, which will include a detailed discussion of the basic properties of the compound, market trends, and new applications of the material. Carrageenans have been traditionally extracted from Rhodophyceae, or red algae, through the use of alkaline processing and precipitation methods; however, current trends have focused on the development of more environmentally friendly processing methods. The nano-formulations of the compound have been utilised in various ways, ranging from the application of the drug delivery system of the compound to the field of medicine, the preservation of food through antimicrobial packaging, agriculture, and environmental remediation technology. The diverse applications of the compound, especially in the field of nanotechnology, have highlighted the versatility of the material, which is used as a substrate in the production of the nano-formulations of the compound. Nevertheless, despite the dynamic applications of the compound, there is still a need to address the challenges that still need to be overcome to fully harness the potential of the material, which may be achieved through the utilisation of enhanced characterisation tools, standard production methods, and the utilisation of extended methods of functionalization of the material. It is also important to note that the establishment of proper regulatory infrastructures will be important in the translation of the potential of the material from the research lab to the industries that may be utilised to harness the potential of the compound.