L Xu1, X Sun, K Cao, Y Wu, D Zou, Y Liu, X Zhang, X Zhang, G Wang, Q Huang, X Jiang. 1. Department of Prosthodontics, Ninth People's Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China; Oral Bioengineering and Regenerative Medicine Lab, Shanghai Research Institute of Stomatology, Ninth People's Hospital, Shanghai Key Laboratory of Stomatology, Shanghai Jiao Tong University, School of Medicine, Shanghai, China.
Abstract
OBJECTIVE: Hypoxic culture potentiates mesenchymal stem cells (MSCs) to survive and secrete various growth factors. Genetically modified stem cells overexpressing bone morphogenic protein-2 (BMP-2) demonstrate strong osteogenic ability. Hence, we investigated the coeffect of hypoxic culture conditions and BMP-2 overexpression on the osteogenic ability of rabbit adipose-derived stem cells (rASCs) in vitro. MATERIALS AND METHODS: Rabbit adipose-derived stem cells with or without adenoviral-BMP-2 transduction were cultured in hypoxic (1%) and normoxic (21%) conditions. Cell viability, attachment, and proliferation were compared. Real-time PCR amplification of osteogenic and angiogenic genes including alkaline phosphatase (ALP), osteocalcin (OCN), HIF-1α, and vascular endothelial growth factor (VEGF) was performed. Moreover, ALP activity, immunofluorescent staining of OCN, and mineralization assay by alizarin red S quantification and von Kossa staining were conducted. RESULTS: Cells under hypoxic conditions attached better within 12 h and proliferated faster. While BMP-2 overexpression and hypoxic condition separately elevated the transcription of key osteogenic and angiogenic genes, a cooperative effect was observed to enhance the upregulation of osteogenic as well as angiogenic genes. Identical changes were observed in ALP activity, immunofluorescent staining of OCN, and mineralization assay. CONCLUSIONS: Hypoxic culture can enhance the osteogenic ability of BMP-2 gene-modified rASCs, which provides a strategy to improve the osteogenesis of rASCs for in vivo bone regeneration.
OBJECTIVE: Hypoxic culture potentiates mesenchymal stem cells (MSCs) to survive and secrete various growth factors. Genetically modified stem cells overexpressing bone morphogenic protein-2 (BMP-2) demonstrate strong osteogenic ability. Hence, we investigated the coeffect of hypoxic culture conditions and BMP-2 overexpression on the osteogenic ability of rabbit adipose-derived stem cells (rASCs) in vitro. MATERIALS AND METHODS:Rabbit adipose-derived stem cells with or without adenoviral-BMP-2 transduction were cultured in hypoxic (1%) and normoxic (21%) conditions. Cell viability, attachment, and proliferation were compared. Real-time PCR amplification of osteogenic and angiogenic genes including alkaline phosphatase (ALP), osteocalcin (OCN), HIF-1α, and vascular endothelial growth factor (VEGF) was performed. Moreover, ALP activity, immunofluorescent staining of OCN, and mineralization assay by alizarin red S quantification and von Kossa staining were conducted. RESULTS: Cells under hypoxic conditions attached better within 12 h and proliferated faster. While BMP-2 overexpression and hypoxic condition separately elevated the transcription of key osteogenic and angiogenic genes, a cooperative effect was observed to enhance the upregulation of osteogenic as well as angiogenic genes. Identical changes were observed in ALP activity, immunofluorescent staining of OCN, and mineralization assay. CONCLUSIONS: Hypoxic culture can enhance the osteogenic ability of BMP-2 gene-modified rASCs, which provides a strategy to improve the osteogenesis of rASCs for in vivo bone regeneration.
Authors: Daniel García-Sánchez; Darío Fernández; José C Rodríguez-Rey; Flor M Pérez-Campo Journal: World J Stem Cells Date: 2019-10-26 Impact factor: 5.326