【摘要】 目的　观察p4 4 /42MAPK、p38MAPK通路在维生素C(VitC)、β 磷酸甘油 (β GP)诱导骨髓间充质干细胞 (BMSCs)向成骨细胞分化过程中的作用。方法　用 [3 H] 甲基胸腺嘧啶掺入率法反映细胞增殖情况 ;测定碱性磷酸酶活性与钙沉积量反映细胞向成骨细胞分化状态 ;用Western blotting法反映MAPK的表达情况。结果　与溶剂对照组相比 ,在促成骨细胞分化剂VitC、β GP作用下 ,骨髓间充质干细胞 (BMSCs)p4 4 /42MAPK、p38MAPK通路均提前 5d激活。p4 4 /42MAPK通路阻断剂(PD980 5 9)明显减少 [3 H] 甲基胸腺嘧啶掺入率 ,抑制BMSCs的增殖 ;而p38MAPK通路的阻断剂(SB2 0 35 80 )则显著降低ALP活性及钙沉积量 ,抑制BMSCs向成骨细胞的分化。结论　p4 4 /42MAPK通路在BMSCs的增殖过程中起重要作用 ,而p38MAPK通路可能与BMSCs向成骨细胞分化调节有关。更多还原

【Abstract】 Objective To investigate the roles of p44/42 and p38MAPK signaling cascades on BMSCs differentiation into osteoblasts induced by Vit C and β-GP. Methods The cell proliferation was assayed by [3H]-thymidine incorporation. The osteoblastic differentiation in BMSCs was assessed by determination of alkaline phosphatase activity (ALP) and calcium deposition. The MAPK signaling activity was detected by Western blotting. Results Western blotting analysis showed that the differentiation media (Vit C and β-GP) resulted in 5 days earlier activation than the control in both p44/42MAPK and p38 MAPK pathways. Vit C and β-GP dramatically increased [3H]-thymidine incorporation and proliferation, and induced ALP activity and clcium deposition in BMSCs cultures. PD98059 (10-25 μM),an inhibitor of p44/42MAPK signaling cascades, resulted in dose-dependent decrease in [3H]-thymidine incorporation, while SB203580 (1-10 μM),an inhibitor of p38MAPK signaling cascades, resulted in dose-dependent reduction in ALP activity and calcium deposition in BMSCs cultures. Conclusion p44/42 MAPK pathway plays an essential role in the proliferation of BMSCs, while p38 MAPK pathway might be involved in osteoblastic differatiation of BMSCs cultures.更多还原