Understanding the molecular mechanism of improved proliferation and osteogenic potential of human mesenchymal stem cells grown on a polyelectrolyte complex derived from non-mulberry silk fibroin and chitosan

Abstract

The development of engineered bone tissue, as a promising alternative to the conventional bone grafts, is not rewarding yet and remained challenging. Thus, attempts have been made in the present study to synthesize polyelectrolyte complex (PEC) scaffolds by blending of chitosan (CS) to silk fibroin (SF) derived from non-mulberry silkworm (Antheraea pernyi) at three different pH (5.0, 6.0, and 7.0), and characterize in terms of morphology, ultrastructure and mechanical properties with SEM, FTIR, XRD and tensile strength analyses. The prepared PEC scaffolds showed mean pore size of 130 µm as revealed by SEM analysis and comparatively higher compressive strength. The findings of in vitro cytocompatibility, in vivo biocompatibility and osteogenic markers (genes/proteins) analysis suggested that the PECs blended at pH 7.0 showed greater stability and enhanced growth and osteogenic differentiation capability of human mesenchymal stem cells (MSCs). To aid our understanding of protein-polyion binding mechanisms, we employed a molecular docking and simulation study of SF macrodomains and CS oligomer using Schrödinger 14 and GROMACS (GROningen Machine for Chemical Simulations) software. The study involved analytical techniques for macromolecular solution characterization and theoretical simulations based on molecular dynamics. The computational studies confirmed the presence of integral RGD sequence that played a vital role in superior cell-attachment, proliferation and osteogenic differentiation of MSCs grown on the developed SF-CS PEC scaffolds.

Chinese Oak Tasar Silkworm Antheraea pernyi Silk Proteins: Current Strategies and Future Perspectives for Biomedical Applications

“…The blending of BmSF with natural polymers, such as chitosan, results in composites combining the biocompatibility and biodegradability of BmSF with the mechanical stability of chitosan . With this reference, Bissoyi et al . have developed polyelectrolyte complexes (PECs) by blending ApSF and chitosan at different pHs (5.0, 6.0, and 7.0).…”

“…ApSF‐based matrices have appealing features for tissue engineering and regenerative applications including cell culture substrates, bone regeneration, bioactive controlled release carriers, and gene delivery systems . Free‐standing ApSF membranes are useful as a vehicle for corneal cell transplantation .…”

Bioactive Silk Fibroin-Based Hybrid Biomaterials for Musculoskeletal Engineering: Recent Progress and Perspectives

“…46 SF/CS hybrid biomaterial is also a promising biomaterial for bone tissue engineering because of the integral RGD sequence, which contributes to the outstanding cell attachment and osteogenic differentiation of hMSCs. 48 Several forms of silk fibroin/chitosan (SF/CS) hybrid biomaterials had been attempted for bone regeneration. To create nanofiber topography in mimicking the ECM structure, Chen et al and Lai et al prepared SF/CS nanofibrous scaffolds for hMSCs and osteoblastic cells' incubation, respectively.…”

Cetyl Trimethyl Ammonium Bromide Modified Montmorillonite‐Doped Tasar Silk Fibroin/Polyvinyl Alcohol Blend 3D Nanowebs for Tissue Engineering Applications

“…It was evident from the previous literature that blending of natural polymers such as silk fibroin with other artificial polymers has enhanced their cytocompatibility and cell adhesion property. [63][64][65][66] This could be attributed to the presence of cell adhesion moieties such as RGD sequence present in silk fibroin. Further, as observed in AFM studies, reinforcement of CTAB-MT has enhanced the surface roughness of the mats which might have aided in the cell adhesion and spreading.…”