Research progress on osteogenic differentiation of adipose-derived stem cell

Abstract

Bone defect due to trauma or tumor resection is the common disease in orthopedics, oral maxillofacial surgery, plastic and reconstructive surgery. Existing methods including artificial bone material filling and bone grafting all have limitations. Adipose-derived stem cell (ASC) is multipotent stem cell isolated from adipose tissue. Stem cell therapy and bone tissue engineering based on the osteogenic differentiation capacity of ASC opens a new era of bone defect repairment and regeneration. The osteogenic differentiation of ASC is a complex procedure associated with interactions of numerous genes, proteins and signal pathways, in which the activation and transcription of Runx2 and Osterix play an important role. Wnt, bone morphogenetic protein, Notch, fibroblast growth factor, cyclic adenosine monophosphate/protein kinase A, Hedgehog and mitogen activated protein kinase are also involed in the regulation of ASC′s osteogenic differentiation. In vitro osteogenic induction of ASC using chemical had been well established. Cell co-culture and various biomaterial scaffold can promote ASC′s osteogenic differentiation. Osteogenic differentiation of ASC can be verified by alizarin staining and detection of osteogenic genes and proteins. Factors that may affect ASC′s osteogenic differentiation include donor factors, experimental factors, growth factors, hormones, medication and chemicals, physical factors, biomechanical factors, micro RNAs, metallic and nonmetallic ions, et al. Although research, clinical trials and applications of ASC osteogenesis are the most focused fields, there are some issues need to be clarified. For example genes, transcription factors, and signal pathways involved in the early stage of ASC′s osteogenic differentiation are still unclear. Interactions between signal pathways are unknown. Factors that may affect ASC′s osteogenic differentiation are lack of summary. Therefore, it is essential to review pathways of ASC′s osteogenic differentiation, to combine growth factors and various scaffold for improvement of ASC′s proliferation and specific differentiation. This review focused on the genes, transcription factors and signal pathways, induction and verification methods, factors and their mechanisms of ASC′s osteogenic differentiation. We also looked forward the future research interest of ASC′s osteogenic differentiation based on current issues. Key words: Transcription factors; Tissue engineering; Regenerative medicine; Adipose-derived stem cell; Differentiation; Genes; Signal pathway