Sialylation: An alternative to designing long-acting and targeted drug delivery system

Long-acting and specific targeting are two important properties of excellent drug delivery systems. Currently, the long-acting strategies based on polyethylene glycol (PEG) are controversial, and PEGylation is incapable of simultaneously possessing targeting ability. Thus, it is crucial to identify and develop approaches to produce long-acting and targeted drug delivery systems. Sialic acid (SA) is an endogenous, negatively charged, nine-carbon monosaccharide. SA not only mediates immune escape in the body but also binds to numerous disease related targets. This suggests a potential strategy, namely “sialylation,” for preparing long-acting and targeted drug delivery systems. This review focuses on the application status of SA-based long-acting and targeted agents as a reference for subsequent research

Structure–Property Correlations of Reactive Oxygen Species-Responsive and Hydrogen Peroxide-Eliminating Materials with Anti-Oxidant and Anti-Inflammatory Activities

To develop reactive oxygen species (ROS)-responsive anti-inflammatory materials and establish their structure–property correlations, a series of H₂O₂-eliminating materials (OxbCDs) were designed and synthesized by conjugating different phenylboronic acid pinacol ester (PBAP) groups onto a biocompatible scaffold compound β-cyclodextrin via varied linker groups. Both the H₂O₂-triggered hydrolysis profiles and H₂O₂-eliminating capacities of these materials were dependent on the chemical structure of the PBAP moieties. Together with the elucidation of hydrolysis mechanisms, we established structure–property correlations of these OxbCD materials. Extensive in vitro experiments revealed nanoparticles (NPs) based on OxbCDs showed no adverse biological effects on normal cells. OxbCD NPs could effectively inhibit inflammatory responses and oxidative stress in stimulated macrophages. Consistently, OxbCD NPs efficaciously alleviated the symptoms of peritonitis in mice, with respect to reducing the counts of neutrophils and macrophages as well as inhibiting the secretion of pro-inflammatory cytokines, chemokines, and oxidative mediators. Similarly, OxbCD NPs loaded with anti-inflammatory drugs displayed superior efficacy in an acute inflammation model of peritonitis in mice. More importantly, OxbCD NPs showed good biocompatibility after administration via different routes. Consequently, besides serving as anti-inflammatory materials, the newly developed H₂O₂-eliminating materials may be utilized as pharmacologically functional carriers for targeted therapy of many diseases associated with inflammation and oxidative stress

Combined application of microbial inoculant and kelp-soaking wastewater promotes wheat seedlings growth and improves structural diversity of rhizosphere microbial community

Abstract Industrial processing of kelp generates large amounts of kelp-soaking wastewater (KSW), which contains a large amount of nutrient-containing substances. The plant growth-promoting effect might be further improved by combined application of growth-promoting bacteria and the nutrient-containing KSW. Here, a greenhouse experiment was conducted to determine the effect of the mixture of KSW and Bacillus methylotrophicus M4-1 (MS) vs. KSW alone (SE) on wheat seedlings, soil properties and the microbial community structure in wheat rhizosphere soil. The available potassium, available nitrogen, organic matter content and urease activity of MS soil as well as the available potassium of the SE soil were significantly different (p < 0.05) from those of the CK with water only added, increased by 39.51%, 36.25%, 41.61%, 80.56% and 32.99%, respectively. The dry and fresh weight of wheat seedlings from MS plants increased by 166.17% and 50.62%, respectively, while plant height increased by 16.99%, compared with CK. Moreover, the abundance and diversity of fungi in the wheat rhizosphere soil were significantly increased (p < 0.05), the relative abundance of Ascomycetes and Fusarium spp. decreased, while the relative abundance of Bacillus and Mortierella increased. Collectively, the combination of KSW and the plant growth-promoting strain M4-1 can promote wheat seedlings growth and improve the microecology of rhizosphere microorganisms, thereby solving the problems of resource waste and environmental pollution, ultimately turning waste into economic gain