A ternary composite hydrogel based on sodium alginate, carboxymethyl cellulose and copper-doped 58S bioactive glass promotes cutaneous wound healing in vitro and in vivo.

Hydrogels offer a novel approach to wound repair. In this study, we synthesized a ternary composite using sodium alginate (SA), carboxymethyl cellulose (CMC) and copper-doped 58S bioactive glass (BG). According to our mechanical testing results, the composite made of 7 wt% CMC and 7 wt% BG (SA-7CMC-7BG) showed optimal properties. In addition, our in vitro studies revealed the biocompatibility and bioactivity of SA-7CMC-7BG, with a negative zeta potential of -31.7 mV. Scanning electron microscope (SEM) images showed 273-µm-diameter pores, cell adhesion, and anchoring. The SA-7CMC-7BG closed 90.4 % of the mechanical scratch after 2 days. An in vivo wound model using Wistar rats showed that SA-7CMC-7BG promoted wound healing, with 85.57 % of the wounds healed after 14 days. Treatment with the SA-7CMC-7BG hydrogel caused a 1.6-, 65-, and 1.87-fold increase in transforming growth factor beta (TGF-ß), Col I, and vascular endothelial growth factor (VEGF) expression, respectively that prevents fibrosis and promotes angiogenesis. Furthermore, interleukin 1ß (IL-1ß) expression was downregulated by 1.61-fold, indicating an anti-inflammatory effect of SA-7CMC-7BG. We also observed an increase in epidermal thickness, the number of fibroblast cells, and collagen deposition, which represent complementary pathology results confirming the effectiveness of the SA-7CMC-7BG hydrogel in cutaneous wound healing.

Wound healing performance of electrospun PVA/70S30C bioactive glass/Ag nanoparticles mats decorated with curcumin: In vitro and in vivo investigations.

Biocompatible fibrous scaffold containing polyvinyl alcohol (PVA), 70S30C bioactive glass (BG), silver (Ag) nanoparticles and curcumin (Cur) was fabricated through electrospinning method. Scanning electron microscope (SEM) and Field emission scanning electron microscopy (FESEM) were employed to investigate the morphological characteristics of the scaffolds. In addition, biodegradability, hydrophilicity, and contact angle were studied as criteria for evaluating physical properties of the scaffolds. Tensile strength was reported to be 0.971 ± 0.093 MPa. Also, the viability of fibroblasts after 7 days of cell culture was 93.58 ± 1.36 %. The antibacterial activity against Escherichia coli and Staphylococcus aureus bacteria was illustrated using inhibition zones of 13.12 ± 0.69 and 14.21 ± 1.37 mm, respectively. Histological results revealed that tissue regeneration after 14 days of surgery was much higher for the dressing group compared to the blank group. According to the obtained results, the authors introduce the PVA-BG-Ag-Cur scaffold as a promising candidate for skin tissue engineering applications.

Multi-leveled Nanosilicate Implants Can Facilitate Near-Perfect Bone Healing.

Several studies have shown that nanosilicate-reinforced scaffolds are suitable for bone regeneration. However, hydrogels are inherently too soft for load-bearing bone defects of critical sizes, and hard scaffolds typically do not provide a suitable three-dimensional (3D) microenvironment for cells to thrive, grow, and differentiate naturally. In this study, we bypass these long-standing challenges by fabricating a cell-free multi-level implant consisting of a porous and hard bone-like framework capable of providing load-bearing support and a softer native-like phase that has been reinforced with nanosilicates. The system was tested with rat bone marrow mesenchymal stem cells in vitro and as a cell-free system in a critical-sized rat bone defect. Overall, our combinatorial and multi-level implant design displayed remarkable osteoconductivity in vitro without differentiation factors, expressing significant levels of osteogenic markers compared to unmodified groups. Moreover, after 8 weeks of implantation, histological and immunohistochemical assays indicated that the cell-free scaffolds enhanced bone repair up to approximately 84% following a near-complete defect healing. Overall, our results suggest that the proposed nanosilicate bioceramic implant could herald a new age in the field of orthopedics.

The anticancer properties of metal-organic frameworks and their heterogeneous nanocomposites.

Herein, silver-based metal-organic framework (AgMOF) and its graphene oxide (GO)-decorated nanocomposite (GO-AgMOF) are proposed for use in emerging biomedical applications. The nanocomposites are characterized, and hence, in vitro apoptotic and antibacterial features of AgMOF and GO-AgMOF nanomaterials were investigated. An MTT cytocompatibility assay indicates that these nanomaterials have dose-dependent toxicity in contact with SW480, colon adenocarcinoma cells. In addition, the cell death mechanism was explored by analyzing flow cytometry and caspase activity. Furthermore, the expressions of pro-apoptotic and anti-apoptotic genes were investigated using quantitative polymerase chain reaction (qPCR). Comparing the control group with the groups treated by the nanomaterials indicates up-regulation of the BAX/BCl2 ratio. We also measured the minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) of these nanomaterials acting on S. mutans and S. aureus, which indicates excellent antibacterial properties. Showing inhibition effect on the viability of cancerous cells through apoptosis and antibacterial effects simultaneously, AgMOF and GO-AgMOF can be regarded as potential therapeutics for cancer.