Self-Assembling Gelatin-Curdlan Fibril Hydrogels for Oriented Neural Cell Growth.

The ex vivo replication of the highly helical and fibril structures of load-bearing soft tissue is a challenging goal for the study of hydrogels. Inspired by nature, we prepared tissue-like physical gels based on curdlan and gelatin by self-assembly. The hybrid gels have a flexible fibril-matrix architecture, and the fibril orientation is highly tunable. The tensile strength of the gels can be tuned from ∼1.1 to ∼16.5 MPa. The coil-helix transition and nanofibril formation process in the self-assembly system was thoroughly investigated. These helical gels exhibit excellent cell compatibility, which supports adhesion and oriented growth of neural cells. Furthermore, the oriented nanofibrils in the gel are found to be associated with an upregulated expression of regeneration-related genes like N-cadherin (Cdh2) and neural growth factor (NGF). Owing to the strength and biomimetic structure, these gels have great potential in tissue engineering applications.

Single-helical formyl ß-glucan effectively deliver CpG DNA with poly(dA) to macrophages for enhanced vaccine effects.

Single helical ß-glucan is a one-dimensional host that can form a hybrid helix with DNAs/RNAs as delivery systems. However, unmodified ß-glucan has a gelling tendency and a single helical conformation is challenging to obtain. Therefore, in this study, we developed a ß-glucan formyl derivative with stable single helical conformation and no gelling tendency. Circular dichroism studies found that the formyl-ß-glucan could form a hybrid helix with DNA CpG-poly(dA). The hybrid helix delivery system showed improved activation on antigen-presenting cells, thereby upregulating the mRNA and protein levels of inflammatory factors, and had an immune-enhancing effect on ovalbumin (OVA) immunized mice. These results indicate that formyl-ß-glucan can be developed as a non-cationic supramolecular DNA delivery platform with low toxicity and high efficiency.

Macrophage-Targeted Berberine-Loaded ß-Glucan Nanoparticles Enhance the Treatment of Ulcerative Colitis.

Aim: This study focuses on constructing of an anti-inflammatory drug delivery system by encapsulation of berberine in the ß-glucan nanoparticles and evaluates its effect on treating ulcerative colitis. Methods: ß-Glucan and the anti-inflammatory drug berberine (BER) are self-assembled into nanoparticles to construct a drug delivery system (GLC/BER). The interaction between the drug and the carrier was characterized by circular dichroism, ultraviolet-visible spectroscopy, and dynamic light scattering. The anti-inflammatory effect of the GLC/BER was evaluated through a lipopolysaccharide (LPS)-induced RAW264.7 macrophage inflammation model and a sodium sulfate (DSS)-induced C57BL/6 mouse ulcerative colitis model. Results: The GLC/BER nanoparticles have a particle size of 80-120 nm and a high encapsulation efficiency of 37.8±4.21%. In the LPS-induced RAW264.7 macrophage inflammation model, GLC/BER significantly promoted the uptake of BER by RAW264.7 cells. RT-PCR and ELISA assay showed that it could significantly inhibit the inflammatory factors including IL-1ß, IL-6 and COX-2. Furthermore, GLC/BER shows inhibiting effect on the secretion of pro-inflammatory factors such as IL-1ß and IL-6, down-regulating the production of nitrite oxide; in animal studies, GLC/BER was found to exert a relieving effect on mice colitis. Conclusion: The study found that GLC/BER has an anti-inflammatory effect in vitro and in vivo, and the GLC carrier improves the potency and bioavailability of BER, providing a new type of nanomedicine for the treatment of colitis.