Strategies for accelerating osteogenesis through nanoparticle-based DNA/mitochondrial damage repair

Gallic Acid-Modified Polyethylenimine-Polypropylene Carbonate-Polyethylenimine Nanoparticles: Synthesis, Characterization, and Anti-Periodontitis Evaluation

The aim of the research was to develop novel gallic acid (GA)-modified amphiphilic nanoparticles of polyethylenimine (PEI)-polypropylene carbonate (PPC)-PEI (PEPE) and comprehensively assess its properties as an antiperiodontitis nanoparticle targeting the Toll-like receptor (TLR). The first step is to evaluate the binding potential of GA to the core trigger receptors TLR2 and TLR4/MD2 for periodontitis using molecular docking techniques. Following this, we conducted NMR, transmission electron microscopy, and dynamic light scattering analyses on the synthesized PEPE nanoparticles. As the final step, we investigated the synthetic results and in vitro antiperiodontitis properties of GA-PEPE nanoparticles. The investigation revealed that GA exhibits potential for targeted binding to TLR2 and the TLR4/MD2 complex. Furthermore, we successfully developed 91.19 nm positively charged PEPE nanoparticles. Spectroscopic analysis indicated the successful synthesis of GA-modified PEPE. Additionally, CCK8 results demonstrated that GA modification significantly reduced the biotoxicity of PEPE. The in vitro antiperiodontitis properties assessment illustrated that 6.25 μM of GA-PEPE nanoparticles significantly reduced the expression of pro-inflammatory factors TNF-α, IL-1β, and IL-6. The GA-PEPE nanoparticles, with their targeted TLR binding capabilities, were found to possess excellent biocompatibility and antiperiodontitis properties. GA-PEPE nanoparticles will provide highly innovative input into the development of anti- periodontitis nanoparticles.

Poly(ethylenimine)-Cyclodextrin-Based Cationic Polymer Mediated HIF-1α Gene Delivery for Hindlimb Ischemia Treatment

Hindlimb ischemia is a common disease worldwide featured by the sudden decrease in limb perfusion, which usually causes a potential threat to limb viability and even amputation or death. Revascularization has been defined as the gold-standard therapy for hindlimb ischemia. Considering that vascular injury recovery requires cellular adaptation to the hypoxia, hypoxia-inducible factor 1 α (HIF-1α) is a potential gene for tissue restoration and angiogenesis. In this manuscript, effective gene delivery vector PEI-β-CD (PC) was reported for the first application in the hindlimb ischemia treatment to deliver HIF-1α plasmid in vitro and in vivo. Our in vitro finding demonstrated that PC/HIF-1α-pDNA could be successfully entered into the cells and mediated efficient gene transfection with good biocompatibility. More importantly, under hypoxic conditions, PC/HIF-1α-pDNA could up-regulate the HUEVC cell viability. In addition, the mRNA levels of VEGF, Ang-1, and PDGF were upregulated, and transcriptome results also demonstrated that the cell-related function of response to hypoxia was enhanced. The therapeutic effect of PC/HIF-1α-pDNA was further estimated in a murine acute hindlimb ischemia model, which demonstrated that intramuscular injection of PC/HIF-1α-pDNA resulted in significantly increased blood perfusion and alleviation in tissue damage, such as tissue fibrosis and inflammation. The results provide a rationale that HIF-1α-mediated gene therapy might be a practical strategy for the treatment of limb ischemia.

Bone regeneration strategies based on organelle homeostasis of mesenchymal stem cells

The organelle modulation has emerged as a crucial contributor to the organismal homeostasis. The mesenchymal stem cells (MSCs), with their putative functions in maintaining the regeneration ability of adult tissues, have been identified as a major driver to underlie skeletal health. Bone is a structural and endocrine organ, in which the organelle regulation on mesenchymal stem cells (MSCs) function has most been discovered recently. Furthermore, potential treatments to control bone regeneration are developing using organelle-targeted techniques based on manipulating MSCs osteogenesis. In this review, we summarize the most current understanding of organelle regulation on MSCs in bone homeostasis, and to outline mechanistic insights as well as organelle-targeted approaches for accelerated bone regeneration.