Effect of dedifferentiation on tendon differentiation of rat bone marrow mesenchymal stem cells

Abstract

Objective \nTo investigate the differentiation potential of rat bone marrow mesenchymal stem cells in dedifferentiation process. \n \n \nMethods \nBone marrow mesenchymal stem cells (BMSCs) of Sprague Dawley rats were isolated and cultured using a whole bone marrow adherent method. BMSCs were induced to dedifferentiate with culture medium containing growth differentiation factor (GDF-5), and then its tendon differentiation was further induced with culture medium containing GDF-5. After 3 weeks, the expression of type Ⅰ (Col Ⅰ), Collagen type Ⅲ (ColⅢ), tenascin-C (TNC), basic Helix-Loop-Helix (scleraxis, SCX) and Tenomodulinwas detected by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting. Results are given as mean±standard deviation. Statistical analysis was performed using Student’s t-test. Multiple comparisons were done using one way ANOVA test. Statistical signicance was set at P<0.05. \n \n \nResults \nThe gene expression of Scx, Col Ⅰ, Col Ⅲ and TNC in experimental group (0.635±0.557, 0.590±0.020, 0.447±0.063, 0.613±0.061 respectively) was significantly higher than that in induced differentiation group (0.416±0.054, 0.406±0.173, 0.294±0.013, 0.373±0.042, t=17.857, P<0.01; t=12.948, P<0.01; t=7.747, P<0.01; t=-5.212, P<0.05) and control group (0.197±0.019, 0.201±0.014, 0.216±0.037, 0.190±0.014, t=31.077, P<0.01; t=14.419, P<0.01; t=15.054, P<0.01; t=8.013, P<0.05). Western blotting indicated that the expression of Col Ⅰ, TNC and Tenomodulin in experimental group (1.705±0.159, 1.587±0.018, 1.616±0.019 respectively)was higher than that in positive control group (1.160±0.018, 1.164±0.016, 1.092±0.022, t=4.825, P<0.05; t=17.395, P<0.05; t=3.961, P<0.05 respectively) and negative group (0.643±0.047, 0.441±0.02l, 0.673±0.015 respectively, t=13.299, P<0.05; t=37.618, P<0.05; t=9.349, P<0.05 respectively). \n \n \nConclusion \nGDF-5 can induce the differentiation of bone marrow mesenchymal stem cells into tendon cells, and the dedifferentiation process can improve the ability of bone marrow mesenchymal stem cells to differentiate into tendon cells. \n \n \nKey words: \nBone mesenchymal stem cells;\xa0Dedifferentiation;\xa0Growth differentiation factor-5;\xa0Differentiation;\xa0Tendon cells