Min Sae Kyung, Kim Minji, Park Jun-Beom
Department of Periodontics, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea.
College of Dentistry, Chosun University, Gwangju 61452, Republic of Korea.
Exp Ther Med. 2021 Apr;21(4):383. doi: 10.3892/etm.2021.9814. Epub 2021 Feb 22.
Insulin-like growth factor 2 (IGF-2) is a growth factor that is involved in various functions of cells, including stem cells. The effects of IGF-2 on the cellular viability and osteogenic differentiation of stem cell spheroids were investigated in the present study. Stem cell spheroids were formed using concave microwells in the presence of IGF-2 at final concentrations of 0, 10 and 100 ng/ml. Cellular viability was measured qualitatively using a microscope and quantitatively using an assay kit based on water-soluble tetrazolium salt. The level of alkaline phosphatase activity, and an anthraquinone dye assay for calcium deposit evaluation, were used to assess osteogenic differentiation. A quantitative PCR analysis was conducted to evaluate the expression of Runx2 and Col1. Spheroid formation was noticed on day 1 in the microwells, and the spheroidal shape was maintained up to day 7. The cell viability assay values for IGF-2 at 0, 10 and 100 ng/ml at day 1 were 0.193±0.002, 0.191±0.002 and 0.201±0.006, respectively (P>0.05). The absorbance values at 405 nm for the alkaline phosphatase activity assays on day 21 were 0.221±0.006, 0.375±0.010 and 0.280±0.015 for IGF-2 at 0, 10 and 100 ng/ml, respectively. There were significantly higher values for IGF-2 in the 10 and 100 ng/ml groups when compared with the control (P<0.05). Significantly higher Alizarin red staining was noted for IGF-2 in the 10 ng/ml group when compared with the unloaded control at day 21 (P<0.05). Quantitative PCR revealed that mRNA levels of Runx2 and Col1 were significantly higher at 100 ng/ml on day 7. Conclusively, the present study demonstrated that the application of IGF-2 increased alkaline phosphatase activity, Alizarin red staining, and Runx2 and Col1 expression of stem cell spheroids.
胰岛素样生长因子2（IGF-2）是一种参与细胞多种功能的生长因子，包括干细胞的功能。本研究调查了IGF-2对干细胞球状体细胞活力和成骨分化的影响。在最终浓度为0、10和100 ng/ml的IGF-2存在下，使用凹形微孔形成干细胞球状体。使用显微镜定性测量细胞活力，并使用基于水溶性四氮唑盐的检测试剂盒进行定量测量。使用碱性磷酸酶活性水平和用于钙沉积评估的蒽醌染料检测来评估成骨分化。进行定量PCR分析以评估Runx2和Col1的表达。在第1天在微孔中观察到球状体形成，并且球形形状维持到第7天。第1天IGF-2浓度为0、10和100 ng/ml时的细胞活力检测值分别为0.193±0.002、0.191±0.002和0.201±0.006（P>0.05）。第21天碱性磷酸酶活性检测在405 nm处的吸光度值，IGF-2浓度为0、10和100 ng/ml时分别为0.221±0.006、0.375±0.010和0.280±0.015。与对照组相比，10和100 ng/ml组中IGF-2的值显著更高（P<0.05）。与第21天未加载对照组相比，10 ng/ml组中IGF-2的茜素红染色显著更高（P<0.05）。定量PCR显示，第7天100 ng/ml时Runx2和Col1的mRNA水平显著更高。总之，本研究表明，IGF-2的应用增加了干细胞球状体的碱性磷酸酶活性、茜素红染色以及Runx2和Col1的表达。
