Polysaccharide-based gold nanomaterials: Synthesis mechanism, polysaccharide structure-effect, and anticancer activity

Polysaccharide-based gold nanomaterials have attracted great interest in biomedical fields such as cancer therapy and immunomodulation due to their prolonged residence time in vivo and enhanced immune response. This review aims to provide an up-to-date and comprehensive summary of polysaccharide-based Au NMs synthesis, including mechanisms, polysaccharide structure-effects, and anticancer activity. Firstly, research progress on the synthesis mechanism of polysaccharide-based Au NMs was addressed, which included three types based on the variety of polysaccharides and reaction environment: breaking of glycosidic bonds via Au (III) or base-mediated production of highly reduced intermediates, reduction of free hydroxyl groups in polysaccharide molecules, and reduction of free amino groups in polysaccharide molecules. Then, the potential effects of polysaccharide structure characteristics (molecular weight, composition of monosaccharides, functional groups, glycosidic bonds, and chain conformation) and reaction conditions (the reaction temperature, reaction time, pH, concentration of gold precursor and polysaccharides) on the size and shape of Au NMs were explored. Finally, the current status of polysaccharide-based Au NMs cancer therapy was summarized before reaching our conclusions and perspectives.

Biofunctionalized Liposomes to Monitor Rheumatoid Arthritis Regression Stimulated by Interleukin-23 Neutralization

Even after the revolution of rheumatoid arthritis (RA) treatment with biologic agents, this debilitating disease remains a major clinical problem. The outstanding outcomes of the systemic administration of antibodies (Abs) are narrowed by the risk of serious side effects and limited efficacy due to their short half-life. Interleukin-23 (IL-23) is a crucial pro-inflammatory cytokine involved in inflammation that potently enhances the generation of T-helper type-17 (Th17) cells. Hence, in this work, anti-IL-23 Abs are immobilized at the surface of liposomes to increase their therapeutic efficacy, being gold nanoparticles (AuNPs) incorporated to allow monitoring the biodistribution of the liposomes after systemic administration as well as due to their anti-inflammatory and antioxidant effects. A stable monodispersed liposomes' suspension with around 130 nm is produced and efficiently biofunctionalized with anti-IL-23 Abs. IL-23 capture and neutralization capacity are confirmed using activated macrophages. Biological assays demonstrate their hemocompatibility and cytocompatibility with human articular chondrocytes, macrophages, and endothelial cells. Moreover, the neutralization of IL-23 by the biofunctionalized liposomes efficiently decreases the production of IL-17A by peripheral blood mononuclear cells of healthy donors and RA patients who are activated to Th17 differentiation. Therefore, the developed formulation may be a promising strategy to treat RA.

Extracellular Matrix Mimics Using Hyaluronan-Based Biomaterials

Hyaluronan (HA) is a critical element of the extracellular matrix (ECM). The regulated synthesis and degradation of HA modulates the ECM chemical and physical properties that, in turn, influence cellular behavior. HA triggers signaling pathways associated with the adhesion, proliferation, migration, and differentiation of cells, mediated by its interaction with specific cellular receptors or by tuning the mechanical properties of the ECM. This review summarizes the recent advances on strategies used to mimic the HA present in the ECM to study healthy or pathological cellular behavior. This includes the development of HA-based 2D and 3D in vitro tissue models for the seeding and encapsulation of cells, respectively, and HA particles as carriers for the targeted delivery of therapeutic agents.

Morphology tunable and acid-sensitive dextran-doxorubicin conjugate assemblies for targeted cancer therapy

Stimuli-responsive and targetable nanomedicine systems have been widely applied as effective modalities for drug delivery and tumor therapeutics. Particle shape is also important for the biodistribution and cellular uptake in drug delivery applications. Here, morphology tunable and acid-responsive dextran-doxorubicin conjugate assemblies of DD-M and DDF-V for targeted doxorubicin (DOX) delivery were constructed, which contain the following favorable advantages: (1) one-pot synthesis of the drug loaded system with a Schiff base reaction is a green chemistry method which is better than the conventional drug conjugation/encapsulation methods. (2) The morphology of the nanoparticles could be regulated from a micelle (DD-M) to vesicle (DDF-V) structure by either introducing folic acid (FA) or not. (3) The abundant hydroxyl groups and electronegativity give DD-M and DDF-V superior stability in the physiological environment. (4) Besides, the multifunctional DDF-V with its important merits including tumor-targeting ability and acid-responsiveness is specific for DOX delivery in cancer therapy. (5) Compared to free DOX and DD-M, DDF-V displayed enhanced anti-tumor efficacy both in vitro and in vivo without obvious systematic toxicity. The morphology tunable, acid-sensitive and targetable nanosystem could be a promising strategy for site-specific drug delivery and potential cancer therapy in the future.

In situ preparation of gold–polyester nanoparticles for biomedical imaging

Hybrid gold-polyester nanoparticles were synthesized by UV irradiation of a gold salt and photoinitiator encapsulated in a polyester nanoparticle. The resulting materials exhibit excellent cellular imaging and surface plasmon resonance properties.

Cationized Bombyx mori silk fibroin as a delivery carrier of the VEGF165-Ang-1 coexpression plasmid for dermal tissue regeneration

The angiogenesis of an implanted construct is among the most important issues in tissue engineering. In this study, spermine was used to modify Bombyx mori silk fibroin (BSF) to synthesize cationized BSF (CBSF). BSF and CBSF were coated in sequence on the surface of polyethyleneimine (PEI)/vascular endothelial growth factor 165/angiopoietin-1 coexpression plasmid DNA (pDNA) complexes to form CBSF/BSF/PEI/pDNA quaternary complexes. BSF scaffolds loaded with carrier/pDNA complexes were prepared as dermal regeneration scaffolds by freeze-drying. In one set of experiments, scaffolds were used to cover a chick embryo chorioallantoic membrane (CAM) to investigate the influence of carrier/pDNA complexes on angiogenesis; in another set of experiments, scaffolds were implanted into dorsal full-thickness wounds in Sprague-Dawley rats to evaluate the effect of carrier/pDNA complex-loaded BSF scaffolds on neovascularization and dermal tissue regeneration. After modification with spermine, the surface zeta potential value of BSF rose to +11 mV from an initial value of -9 mV, and the isoelectric point of BSF increased from 4.20 to 9.04. The in vitro transfection of human umbilical vein endothelial cells (EA.hy926) with quaternary complexes revealed that the CBSF/BSF/PEI/pDNA complexes clearly exhibited lower cytotoxicity and higher transfection efficiency than the PEI/pDNA complexes. The CAM assay showed a more abundant branching pattern of blood vessels in BSF scaffolds loaded with CBSF/BSF/PEI/pDNA complexes than in BSF scaffolds without complexes or loaded with PEI/pDNA complexes. The in vivo experimental results demonstrated that the incorporation of CBSF/BSF/PEI/pDNA complexes could effectively enhance angiogenesis in the implanted BSF scaffolds, thereby promoting the regeneration of dermal tissue, providing a new scaffold for the regeneration of dermal tissue and other tissues containing blood vessels.