Electrospun scaffold containing TGF-β1 promotes human mesenchymal stem cell differentiation towards a nucleus pulposus-like phenotype under hypoxia

Reviving Intervertebral Discs: Treating Degeneration Using Advanced Delivery Systems

Intervertebral disc degeneration (IVDD) is commonly associated with many spinal problems, such as low back pain, and significantly impacts a patient's quality of life. However, current treatments for IVDD, which include conservative and surgical methods, are limited in their ability to fully address degeneration. To combat IVDD, delivery-system-based therapy has received extensive attention from researchers. These delivery systems can effectively deliver therapeutic agents for IVDD, overcoming the limitations of these agents, reducing leakage and increasing local concentration to inhibit IVDD or promote intervertebral disc (IVD) regeneration. This review first briefly introduces the structure and function of the IVD, and the related pathophysiology of IVDD. Subsequently, the roles of drug-based and bioactive-substance-based delivery systems in IVDD are highlighted. The former includes natural source drugs, nonsteroidal anti-inflammatory drugs, steroid medications, and other small molecular drugs. The latter includes chemokines, growth factors, interleukin, and platelet-rich plasma. Additionally, gene-based and cell-based delivery systems are briefly involved. Finally, the limitations and future development of the combination of therapeutic agents and delivery systems in the treatment of IVDD are discussed, providing insights for future research.

Nanotechnology development in surgical applications: recent trends and developments

This paper gives a detailed analysis of nanotechnology's rising involvement in numerous surgical fields. We investigate the use of nanotechnology in orthopedic surgery, neurosurgery, plastic surgery, surgical oncology, heart surgery, vascular surgery, ophthalmic surgery, thoracic surgery, and minimally invasive surgery. The paper details how nanotechnology helps with arthroplasty, chondrogenesis, tissue regeneration, wound healing, and more. It also discusses the employment of nanomaterials in implant surfaces, bone grafting, and breast implants, among other things. The article also explores various nanotechnology uses, including stem cell-incorporated nano scaffolds, nano-surgery, hemostasis, nerve healing, nanorobots, and diagnostic applications. The ethical and safety implications of using nanotechnology in surgery are also addressed. The future possibilities of nanotechnology are investigated, pointing to a possible route for improved patient outcomes. The essay finishes with a comment on nanotechnology's transformational influence in surgical applications and its promise for future breakthroughs.

Comparison of the differentiation abilities of bone marrow-derived mesenchymal stem cells and adipose-derived mesenchymal stem cells toward nucleus pulposus-like cells in three-dimensional culture

Nucleus pulposus cell (NPC) transplantation can be a potential therapeutic approach for intervertebral disc degeneration (IDD). However, low cell viability has restricted the therapeutic capacity of NPCs, and sources of natural NPCs are limited. Bone marrow-derived mesenchymal stem cells (BMSCs) and adipose-derived mesenchymal stem cells (ADSCs) can be differentiated toward NPC-like cells. However, it is unknown whether there are differences in the abilities of these two cell types to differentiate into NPC-like cells, or which cell type exhibits the best differentiation ability. The present study compared the abilities of BMSCs and ADSCs to differentiate toward NPC-like cells with or without a 3D culture system to lay a foundation for stem cell transplantation therapy for IDD. BMSCs were isolated from the rat whole bone marrow cell using the repeated adherent culture method. ADSCs were isolated from rat adipose tissues in the subcutaneous inguinal region using the enzyme digestion method. Cells were identified using flow cytometry. Cell viability was assessed via Cell Counting Kit-8 assays, and reverse transcription-quantitative PCR and western blotting were carried out to evaluate the expression of NPC markers and chondrocyte-specific genes. Glycosaminoglycans (GAGs) and proteoglycans were examined via Alcian blue and safranin O staining, respectively. ADSCs in 3D culture displayed the highest cell proliferative ability, compared with the 2D culture system and BMSC culture. In addition, ADSCs in 3D culture exhibited increased GAG and proteoglycan synthesis than BMSCs. Compared with BMSCs in 3D culture, ADSCs in 3D culture exhibited higher mRNA and protein expression of NPC marker genes (hypoxia-inducible factor 1-α, glucose transporter 1) and chondrocyte-specific genes (Sox-9, aggrecan and type II collagen). The present findings indicated that ADSCs exhibited a better ability to differentiate into NPC-like cells in 3D culture compared with BMSCs, which may be of value for the regeneration of intervertebral discs using cell transplantation therapy.

In the presence of TGF-β1, Asperosaponin VI promotes human mesenchymal stem cell differentiation into nucleus pulposus like- cells

Background

The regeneration of nucleus pulposus (NP) cells is an effective method to prevent intervertebral disc degeneration (IVDD). In this study, we investigated the role of Asperosaponin VI (ASA VI), isolated from a traditional Chinese medicine (TCM), the root of Dipsacus asper Wall, in promoting human mesenchymal stem cell (HMSC) proliferation and differentiation into NP-like cells and explored the possible mechanism of action.

Methods

The effects of ASA VI on HMSC viability and proliferation were determined by the XTT method and EDU staining. Then, Real-time qPCR, immunocytochemistry and immunofluorescence assays were used to measure the effect of ASA VI on the expression of extracellular matrix (ECM) components, such as COL2A1, aggrecan, SOX9, KRT19, PAX1, and glycosaminoglycans (GAGs), in NP cells. In addition, Western blot assay was used to measure the expression of p-ERK1/2 and p-smad2/3.

Results

ASA VI was able to promote the proliferation and differentiation of HMSCs into NP-like cells, and the optimum concentration was 1 mg/L. Western blot assay indicated that the possible mechanism might be related to the activation of p-ERK1 / 2 and p-Smad2 / 3.

Conclusions

ASA VI can promote the proliferation and differentiation of HMSCs into NP-like cells, which can potentially be used as a treatment for IVDD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-020-03169-y.

Nanotechnology in orthopedics: a clinically oriented review

The utility of nanotechnology in medicine, specifically within the field of orthopedics, is a topic of extensive research. Our review provides a unique comprehensive overview of the current and potential future uses of nanotechnology with respect to orthopedic sub-specialties. Nanotechnology offers an immense assortment of novel applications, most notably the use of nanomaterials as scaffolds to induce a more favorable interaction between orthopedic implants and native bone. Nanotechnology has the capability to revolutionize the diagnostics and treatment of orthopedic surgery, however the long-term health effects of nanomaterials are poorly understood and extensive research is needed regarding clinical safety.

The Use of Electrospinning Technique on Osteochondral Tissue Engineering

Electrospinning, an electrostatic fiber fabrication technique, has attracted significant interest in recent years due to its versatility and ability to produce highly tunable nanofibrous meshes. These nanofibrous meshes have been investigated as promising tissue engineering scaffolds since they mimic the scale and morphology of the native extracellular matrix. The sub-micron diameter of fibers produced by this process presents various advantages like the high surface area to volume ratio, tunable porosity, and the ability to manipulate the nanofiber composition in order to get desired properties and functionality. Electrospun fibers can be oriented or arranged randomly, giving control over both mechanical properties and the biological response to the fibrous scaffold. Moreover, bioactive molecules can be integrated with the electrospun nanofibrous scaffolds in order to improve the cellular response. This chapter presents an overview of the developments on electrospun polymer nanofibers including processing, structure, and their applications in the field of osteochondral tissue engineering.

Preparation and properties of poly(ε-caprolactone)/bioactive glass nanofibre membranes for skin tissue engineering

Poly(ε-caprolactone) composite nanofibres for skin tissue engineering and regeneration applications were prepared via electrospinning of poly(ε-caprolactone) nanofibres with bioactive glass nanoparticles at bioactive glass contents of 0, 2, 4, 6 and 8 wt%. The surface properties, water absorptivities, porosities, mechanical properties and biocompatibilities of the composite electrospun nanofibres were characterised in detail. Addition of bioactive glass improved the hydrophilicity and elastic modulus of membranes. The fibre diameter of the neat poly(ε-caprolactone) nanofibres was only 700 nm, but reinforcement with 2, 4, 6 and 8 wt% bioactive glass nanofibres increased the diameter to 1000, 1100, 900 and 800 nm, respectively. The minimum elongation at break of the bioactive glass–reinforced poly(ε-caprolactone) exceeded 100%, which indicated that the composite nanofibres had good mechanical properties. The porosities of the various nanofibres containing different mass loadings of bioactive glass all exceeded 90%. The best performance in terms of cell proliferation and adhesion was found when the bioactive glass mass percent reached 6 wt%. However, higher loadings were unfavourable for cell growth. These preliminary results indicate that poly(ε-caprolactone)/bioactive glass composite nanofibres have promise for skin tissue engineering applications.