Enhancing osteogenic differentiation of mesenchymal stem cells seeded on a polycaprolactone/MoS2 nanofibrous scaffold through electrical stimulation

Abstract

Recent progress in bone tissue engineering (BTE) has introduced alternative treatments for sizable and non-healing bone defects. Electrical stimulation (ES) has recently been shown to influence bone cells and foster processes such as adhesion, migration, proliferation, and differentiation, which can enhance the bone regeneration process. In this study, we synthesized molybdenum disulfide (MoS₂) nanoparticles (NPs) and incorporated them into a polycaprolactone (PCL) polymeric matrix to enhance the electrical conductivity of scaffolds. The PCL/MoS₂ nanocomposites were analysed using scanning electron microscopy (SEM), water contact angle measurement, electrical conductivity, and tensile strength assessments. In vitro studies evaluated the adhesion of mesenchymal stem cells (MSCs) and the biocompatibility of the fabricated scaffolds using the MTT assay. Biomineral crystal deposition was determined via in vitro simulated body fluid (SBF) biomineralization, and alizarin red S assays demonstrated enhanced calcium phosphate deposition on the PCL/MoS₂ composite scaffold. Additionally, qPCR analysis revealed that exposing MSCs cultured on PCL/MoS₂ to ES for two weeks transcriptionally upregulated osteogenic markers (osteocalcin (OC) and alkaline phosphatase (ALP)) in cells. Using either ES or a differentiation medium alone could enhance osteogenesis. However, when both stimuli were applied concurrently, improved levels of osteogenic markers were observed. Our findings suggest that ES plays a significant role in boosting osteogenic differentiation, particularly when combined with MoS₂NPs as an osteogenic enhancer. Therefore, PCL/MoS₂ nanofibrous scaffolds can be proposed as suitable candidates for BTE, and ES holds great potential as an effective tool along with commonly used biomaterial scaffolds.