Hao Wei, Jiang Chuanqiang, Jiang Ming, Wang Tian, Wang Xin
Department of Orthopedics and Traumatology, Yantai Yuhuangding Hospital Affiliated to Qingdao University Medical College, Yantai, Shandong 264000, P.R. China.
Department of Orthopedics and Traumatology, Yantaishan Hospital, Yantai, Shandong 264000, P.R. China.
Exp Ther Med. 2017 Jul;14(1):43-50. doi: 10.3892/etm.2017.4465. Epub 2017 May 17.
Mature adipocytes are the major cell type in adipose tissue. This study aimed to explore the osteogenic potency of dedifferentiated fat cells obtained from osteoporotic patients (opDFATs) and . Mature adipocytes and adipose-derived stem cells (opASCs) were harvested from subcutaneous adipose tissue. Mature adipocytes were dedifferentiated to produce opDFATs by the ceiling culture method. OpDFATs were osteogenically induced with opASCs as a control. Cell growth, alkaline phosphatase (ALPase) activity and cell mineralization were determined, and expression levels of osteogenesis-specific genes (collagen I, osteocalcin and bone sialoprotein) were analyzed using quantitative reverse transcription polymerase chain reaction. After 14 days, the opDFATs were combined with a poly(lactide-co-glycolide)-β-tricalcium phosphate porous scaffold after being suspended in collagen I gel and implanted into nude mice for 4 weeks prior to histological analysis. Unilocular lipid droplets in mature adipocytes gradually split into smaller droplets and disappeared from the cytoplasm. Mature adipocytes dedifferentiated to opDFATs and cell morphology changed from spherical to elongated. High levels of ALPase and cell mineralization were observed in opDFATs by staining. No significant differences were found between the growth curves, ALPase activity, cell mineralization and expression levels of osteogenesis-specific genes between opDFATS and opASCs. After implantation for 4 weeks, new bone tissue was observed histologically in the opDFATs-based biocomposite. OpDFATs are implicated as a novel type of seed cell for bone tissue engineering based on their osteogenic potency and higher abundance in adipose tissue compared with opASCs.
成熟脂肪细胞是脂肪组织中的主要细胞类型。本研究旨在探索从骨质疏松症患者获得的去分化脂肪细胞（opDFATs）的成骨潜能。从皮下脂肪组织中获取成熟脂肪细胞和脂肪来源干细胞（opASCs）。通过悬滴培养法将成熟脂肪细胞去分化以产生opDFATs。以opASCs作为对照对opDFATs进行成骨诱导。测定细胞生长、碱性磷酸酶（ALPase）活性和细胞矿化，并使用定量逆转录聚合酶链反应分析成骨特异性基因（胶原蛋白I、骨钙素和骨唾液蛋白）的表达水平。14天后，将opDFATs悬浮于胶原蛋白I凝胶中后与聚（丙交酯-共-乙交酯）-β-磷酸三钙多孔支架结合，并植入裸鼠体内4周，然后进行组织学分析。成熟脂肪细胞中的单房脂质小滴逐渐分裂成较小的小滴并从细胞质中消失。成熟脂肪细胞去分化为opDFATs，细胞形态从球形变为细长形。通过染色在opDFATs中观察到高水平的ALPase和细胞矿化。opDFATs与opASCs在生长曲线、ALPase活性、细胞矿化和成骨特异性基因表达水平方面未发现显著差异。植入4周后，在基于opDFATs的生物复合材料中组织学观察到新骨组织。基于opDFATs的成骨潜能以及与opASCs相比在脂肪组织中更高的丰度，opDFATs被认为是骨组织工程的一种新型种子细胞。
