Fabrication of Pentoxifylline-Loaded Hydroxyapatite/Alginate Scaffold for Bone Tissue Engineering

Abstract

Background: Hydroxyapatite (HAP), as a common biomaterial in bone tissue engineering, can be fabricated in combination with other osteogenic agents. Pentoxifylline (PTX) is demonstrated to have positive roles in bone defect healing. Since local administration can diminish the systemic side effects of the drug, the objectives of the current in vitro study were to find the effects of PTX on the osteoblast functions for tissue engineering applications. Methods: a HAP scaffold was fabricated by casting the HAP slurry within polyurethane foam. The scaffold was enriched with 5 mg/mL PTX. Alginate (Alg) was used as drug carrier to regulate the PTX releasing rate. MG-63 osteosarcoma cells were cultured on 3D scaffolds and 2D Alg films in the presence or absence of PTX. Results: PTX did not affect the cell viability, attachment and phenotype. Also, the ultrastructure of the scaffolds was not modified by PTX enrichment. Alizarin red S staining showed that PTX has no effect on calcium deposition. Besides, Raman confocal microscopy demonstrated an increase in the organic matrix formation including proline, valine and phenylalanine deposition (represented collagen). Although PTX increased the total protein secretion, it led to a decrease in the alkaline phosphatase activity and vascular endothelial growth factor (VEGF) content. PTX reduced the hydration and degradation rates and it was released mainly at the first 24 hours of incubation. Conclusion: Based on our in vitro study, application of engineered PTX-loaded HAP scaffold in bone regeneration can act on behalf of organic matrix production, but not angiogenesis and mineralization.

Thymoquinone loading into hydroxyapatite/alginate scaffolds accelerated the osteogenic differentiation of the mesenchymal stem cells

“…The current evidence indicates that TQ elevates osteoblast differentiation without considerable impact on the physical and mechanical properties of the scaffold Enrichment of the HA with osteogenic induced agents has been reported previously [ 39 ]. Quinones with a wide range of biological activities and applications have several beneficial effects on bone formation.…”

Utilize Chitosan to Coat Hydroxyapatite on Polymer

“…PEEK is also physically and chemically stable, and it may be changed by physical or chemical treatments to enhance activity [7]. For the increased attachment between bone-implant, they coated the implant with bioceramics such as hydroxyapatite (HA) has been extensively employed for orthopedic applications owing to its superior osteoconductivity, biocompatibility, and is similar to the inorganic component of bone [10,11]. An important consideration of bioresorbable coating is the crystalline form of HA, which has a substantially lower solubility and dissolution rate in vivo than amorphous HA.…”