Anionic carbohydrate-containing chitosan scaffolds for bone regeneration

Abstract

Scaffolds derived from naturally occurring polysaccharides have attracted significant interest in bone tissue engineering due to their excellent biocompatibility and hydrophilic nature favorable for cell attachment. In this study, we developed composite chitosan (CH) scaffolds containing anionic carbohydrate, such as chondroitin 4-sulfate (CS) or alginate (AG), with biomimetic apatite layer on their surfaces, and investigate their capacity to deliver progenitor cells (bone marrow stromal cells, BMSC) and model proteins with net-positive (histone) and net-negative charge (bovine serum albumin, BSA). The incorporation of CS or AG in CH scaffolds increased compressive modulus of the scaffolds and enhanced apatite formation. Initial burst release of histone was significantly higher than that of BSA from CH scaffold, while the addition of CS or AG in the scaffolds significantly reduced the initial burst release of histone, indicating strong electrostatic interaction between histone and negatively charged CS or AG. The apatite layer created on scaffold surfaces significantly reduced the initial burst release of both BSA and histone. Furthermore, apatite-coated scaffolds enhanced spreading, proliferation, and osteogenic differentiation of BMSC seeded on the scaffolds compared to non-coated scaffolds as assessed by live/dead and alamarBlue assays, scanning electron microscopy (SEM), alkaline phosphatase (ALP) activity, and Picrosirius red staining. This study suggests that apatite-coated CH/CS composite scaffolds have the potential as a promising osteogenic system for bone tissue engineering applications.

Delivery of Phenamil Enhances BMP-2-Induced Osteogenic Differentiation of Adipose-Derived Stem Cells and Bone Formation in Calvarial Defects

“…We previously developed a biomimetic process to create apatite layers on various biomaterial surfaces, and the created apatite provided a favorable substrate for cell adhesion and osteogenic differentiation. 20,[22][23][24] This study showed that loaded BMP-2 and phenamil were slowly released in a sustainable manner with approximately 7% and 29% of initial burst from scaffolds, respectively. The observed sustained release of BMP-2 can be attributed to increased electrostatic interaction between BMP-2 and charged binding sites on the apatite surface.…”

“…20,22 Briefly, simulated body fluids (SBF) were prepared by sequentially dissolving CaCl 2 , MgCl 2 $6H 2 O, NaHCO 3 , and K 2 HPO 4 $3H 2 O into ddH 2 O. The solution was adjusted to pH 6.0 and then Na 2 SO 4 , KCl, and NaCl were added.…”

“…In prior work, we developed biomimetic apatite layers on the various surfaces of complex three-dimensional (3D) scaffolds, including poly(lactic-co-glycolic acid) (PLGA), tricalcium phosphate, and chitosan (CH), which not only promoted osteogenic activities of progenitor cells but also presented a sustained release of loaded proteins with a reduced initial burst. [20][21][22][23] Our recent study demonstrated that controlled BMP-2 delivery can be achieved by apatite coating and BMP-2-loaded scaffolds enhance osteogenesis of adipose-derived stem cells (ASCs) in vitro and promote bone regeneration in rodent models. 24 Although previous studies have demonstrated that phenamil can induce osteogenic differentiation by enhancing BMP activity, and combined application of phenamil with BMP-2 can enhance osteogenesis in vitro, 14,[16][17][18][19] no single study reported the ability of phenamil to promote bone regeneration and how phenamil delivery influences BMP-2-mediated bone formation in vivo.…”

In vitro and in vivo evaluation of thermosensitive chitosan hydrogel for sustained release of insulin

“…Chitosan consists of b-(1,4)-linked D-glucosamine units with variable degrees of N-acetylation (Casettari et al, 2012). It has been used for tissue regeneration (Ma et al, 2010;Cooper et al, 2011;Park et al, 2013) and drug delivery applications (Rokhade et al, 2007;Abruzzo et al, 2012;Ferrari et al, 2013) because of its tissue compatibility, biodegradability and low toxicity (Ao et al, 2011;Cooper et al, 2011;Tsai et al, 2011).…”

Desenvolvimento e caracterização de scaffolds à base de fibras de alginato e quitosana para aplicações médicas

“…Por apresentarem essas propriedades, são utilizados em aplicações médicas (PETRULYTE;; PETRULIS, 2011;; MEDINE et al, 2012).…”