Amir Lisa R, Suniarti Dewi F, Utami Sri, Abbas Basril
Department of Oral Biology, Faculty of Dentistry, Universitas Indonesia, Salemba Raya No.4, Jakarta Pusat, 10430, Indonesia,
Cell Tissue Res. 2014 Nov;358(2):407-15. doi: 10.1007/s00441-014-1938-1. Epub 2014 Jul 4.
Chitosan, a natural biopolymer derived from chitin, is considered a promising scaffold material for bone tissue engineering. The ability of chitosan to promote the osteogenic differentiation of dental pulp stromal/stem cells (DPSCs) is unknown. We have evaluated the potential of chitosan to induce the osteogenic differentiation of macaque DPSCs in comparison with that of dexamethasone. DPSCs were cultured in mineralizing medium supplemented with 5 or 10 μg/ml chitosan or with 1 or 10 nM dexamethasone. The metabolic activity of DPSCs was measured by MTT assay. Their osteogenic differentiation was determined by the number of transcripts of RUNX2, alkaline phosphatase (ALP), and COL1A1 by using real-time polymerase chain reaction, by alizarin red staining for mineral deposition, and by the ALP activity released into the medium for their ability to support biomineralizaton. Addition of chitosan to the mineralizing medium significantly increased DPSCs metabolism after 7 and 14 days of culture (P ≤ 0.0001). Chitosan at 5 μg/ml also significantly enhanced RUNX2 and ALP mRNA but not COL1A1 mRNA; chitosan tended to increase the release of ALP hydrolytic enzyme activity into the medium during the first week. Dexamethasone upregulated the osteogenic markers tested. Mineral deposition was similar in the chitosan and dexamethasone groups and was not statistically different from that of the mineralizing control group. Thus, the potential of chitosan to stimulate DPSCs proliferation and early osteogenic differentiation is comparable with that of dexamethasone, but mineralization remains unaffected by chitosan treatment. In addition to its role as a three-dimensional scaffold for osteogenic cells in vivo, chitosan might also stimulate DPSCs proliferation and early osteogenic differentiation in vitro.
壳聚糖是一种从几丁质衍生而来的天然生物聚合物，被认为是骨组织工程中有前景的支架材料。壳聚糖促进牙髓基质/干细胞（DPSCs）成骨分化的能力尚不清楚。我们评估了壳聚糖与地塞米松相比诱导猕猴DPSCs成骨分化的潜力。DPSCs在补充有5或10μg/ml壳聚糖或1或10nM地塞米松的矿化培养基中培养。通过MTT法测量DPSCs的代谢活性。通过实时聚合酶链反应测定RUNX2、碱性磷酸酶（ALP）和COL1A1的转录本数量来确定它们的成骨分化，通过茜素红染色检测矿物质沉积，并通过释放到培养基中的ALP活性来评估其支持生物矿化的能力。在矿化培养基中添加壳聚糖在培养7天和14天后显著增加了DPSCs的代谢（P≤0.0001）。5μg/ml的壳聚糖也显著增强了RUNX2和ALP mRNA，但没有增强COL1A1 mRNA；在第一周，壳聚糖倾向于增加ALP水解酶活性向培养基中的释放。地塞米松上调了所测试的成骨标志物。壳聚糖组和地塞米松组的矿物质沉积相似，与矿化对照组相比无统计学差异。因此，壳聚糖刺激DPSCs增殖和早期成骨分化的潜力与地塞米松相当，但壳聚糖处理对矿化没有影响。除了在体内作为成骨细胞的三维支架的作用外，壳聚糖还可能在体外刺激DPSCs增殖和早期成骨分化。
