The Role of Insulin-Like Growth Factor-2 on the Cellular Viability and Differentiation to the Osteogenic Lineage and Mineralization of Stem Cells Cultured on Deproteinized Bovine Bone Mineral

Abstract

Insulin-like growth factors (IGFs) plays various roles, including differentiation and mitogenesis, and IGFs are reported to regulate the bone growth and maintenance. This study was performed to analyze the enhancing effects of IGF-2 on osteogenic differentiation and the mineralization of stem cells cultured on deproteinized bovine bone mineral. Stem cell loaded bone graft material was cultured in the presence of the IGF-2 at final concentrations of 10 and 100 ng/mL and the morphology of the cells was observed on Days 1, 3, and 7. The commercially available, two-color assay based on plasma membrane integrity and esterase activity was also used for qualitative analyses on Days 1, 3, and 7. The level of alkaline phosphatase activity and anthraquinone dye assay were used to evaluate osteogenic differentiation on Days 7 and 14. Real-time polymerase chain reaction was applied in order to identify the mRNA expression of BGLAP, Runx2, and β-catenin. The stem cells were well-attached with fibroblast morphology and most of the stem cells produced a high intensity of green fluorescence, indicating that there were live cells on Day 1. The relative cellular viability assay values for IGF-2 groups at 0, 10, and 100 ng/mL on Day 1 were 0.419 ± 0.015, 0.427 ± 0.013, and 0.500 ± 0.030, respectively (p < 0.05). The absorbance values at 405 nm for alkaline phosphatase activity on Day 7 for IGF-2 at 0, 10, and 100 ng/mL were 2.112 ± 0.152, 1.897 ± 0.144, and 2.067 ± 0.128, respectively (p > 0.05). The mineralization assay results at Day 7 showed significantly higher values for IGF-2 groups at 10 and 100 ng/mL concentration when compared to the control (p < 0.05). The application of IGF-2 groups of 10 and 100 ng/mL produced a significant increase of BGLAP. Conclusively, this study indicates that the use of IGF-2 on stem cell loaded bone graft increased cellular viability, Alizarin red staining, and BGLAP expression of stem cells. This report suggests the combined approach of stem cells and IGF-2 with scaffold may have synergistic effects on osteogenesis.

Effects of noni on cellular viability and osteogenic differentiation of gingiva‑derived stem cells demonstrated by RNA sequencing and quantitative PCR

“…This is consistent with a previous study that assessed the effects of noni using three-dimensional cultures ( 14 ). However, no noticeable effects of noni on cellular viability were exhibited, which may be due to the nature of the culture condition and exchange of nutrients, gases and waste materials ( 33 , 34 ).…”

Effects of Connective Tissue Growth Factor on the Cell Viability, Proliferation, Osteogenic Capacity and mRNA Expression of Stem Cell Spheroids

“…The results suggest that CTGF enhances the transcription factor and this leads to the increase in the expression of genes involved in osteogenic differentiation. These may lead to higher deposition of calcium deposits, which may be revealed as higher Alizarin red S staining [38].…”