Delivery of miRNAs Using Porous Silicon Nanoparticles Incorporated into 3D Hydrogels Enhances MSC Osteogenesis by Modulation of Fatty Acid Signaling and Silicon Degradation.

Strategies incorporating mesenchymal stromal cells (MSC), hydrogels and osteoinductive signals offer promise for bone repair. Osteoinductive signals such as growth factors face challenges in clinical translation due to their high cost, low stability and immunogenicity leading to interest in microRNAs as a simple, inexpensive and powerful alternative. The selection of appropriate miRNA candidates and their efficient delivery must be optimised to make this a reality.

Cell-laden injectable microgels: Current status and future prospects for cartilage regeneration.

Injectable hydrogels have been employed extensively as versatile materials for cartilage regeneration due to their excellent biocompatibility, tunable structure, and ability to accommodate bioactive factors, as well as their ability to be locally delivered via minimally invasive injection to fill irregular defects. More recently, in vitro and in vivo studies have revealed that processing these materials to produce cell-laden microgels can enhance cell-cell and cell-matrix interactions and boost nutrient and metabolite exchange. Moreover, these studies have demonstrated gene expression profiles and matrix regeneration that are superior compared to conventional injectable bulk hydrogels.

Interplay of Hydrogel Composition and Geometry on Human Mesenchymal Stem Cell Osteogenesis.

Microgels are emerging as an outstanding platform for tissue regeneration because they overcome issues associated with conventional bulk/macroscopic hydrogels such as limited cell-cell contact and cell communication and low diffusion rates. Owing to the enhanced mass transfer and injectability via a minimally invasive procedure, these microgels are becoming a promising approach for bone regeneration applications. Nevertheless, there still remains a huge gap between the understanding of how the hydrogel matrix composition can influence cell response and overall tissue formation when switching from bulk formats to microgel format, which is often neglected or rarely studied.

Amino acid-modified chitosan nanoparticles for Cu chelation to suppress CuO nanoparticle cytotoxicity.

The extensive development and application of engineered nanoparticles (NPs) in various fields worldwide have been subjected to increasing concern due to their potential hazards to human health and the environment. Therefore, a simple, economical, and effective method for suppressing the toxicity of metal-based nanomaterials is needed. In this study, glutaraldehyde-crosslinked chitosan nanoparticles (CS NPs) were prepared and further modified with lysine (Ly-CS), glutamic acid (Glu-CS), or sodium borohydride reduction (R-CS), and used to suppress cytotoxicity induced by copper oxide NPs (CuO NPs) through chelation with intracellularly released copper ions.

Influence of titanium dioxide nanorods with different surface chemistry on the differentiation of rat bone marrow mesenchymal stem cells.

In this study, four kinds of TiO nanorods (TiO NRs), with similar aspect ratios but different surface functional groups, i.e. amines (-NH), carboxyl groups (-COOH) and poly(ethylene glycol) (-PEG), were used to study their interaction with rat bone marrow stem cells (MSCs).

Citrate-capped iron oxide nanoparticles impair the osteogenic differentiation potential of rat mesenchymal stem cells.

Surface modification of iron oxide nanoparticles may cause unexpected impact upon interaction with cells, such as cytotoxicity and change in the differentiation potential of stem cells. In this study, two kinds of iron oxide nanoparticles with different surface chemistries, i.e.