IGF-1通过PI3K/AKT信号通路促进牙髓细胞增殖及碱性磷酸酶活性的研究

目的:研究IGF-1对牙髓细胞增殖和碱性磷酸酶(ALP)活性及PI3K/AKT信号通路的影响。方法:采用酶消化法分离培养原代人牙髓细胞。Western blot检测牙髓组织中IGF-1蛋白表达,不同浓度的IGF-1处理牙髓细胞7d,CCK8法检测细胞增殖。用IGF-1(100 μg/L)及LY294002(10 μmol/L)分别单独或同时处理牙髓细胞,培养7 d后MTT实验检测细胞增殖;在培养第3、5、7、14天时检测细胞ALP 活性;在培养第7天时用Western blot检测AKT和p-AKT蛋白表达情况。结果:IGF-1在牙髓炎组织中低表达, IGF-1在20~100 μg/L浓度范围内从作用第3天开始能够显著促进牙髓细胞增殖(P<0.05或P<0.01),且具有剂量和时间依赖效应。LY294002能够抑制牙髓细胞的增殖和碱性磷酸酶活性,具有时间依赖性。IGF-1能促进p-AKT蛋白表达,而 LY294002能减低IGF-1对p-AKT蛋白表达的促进作用。结论:IGF-1可以促进牙髓细胞增殖和碱性磷酸酶活性,且具有浓度和时间依赖性,作用机制可能与PI3K/AKT信号通路相关。关键词] 牙髓细胞 细胞增殖 碱性磷酸酶

Promotion of IGF-1 on the Proliferation and Alkaline Phosphatase Activity of Dental Pulp Cells through PI3K/AKT Signaling Pathway in Vitro.

Objective: To study the effect of IGF-1 on the proliferation and alkaline phosphatase activity of dental pulp cells and its influences on PI3K/AKT signal pathway. Methods: Primary human dental pulp cells were isolated and cultured by enzymatic digestion. IGF-1 protein expression in dental pulp tissue was detected by Western blot. The dental pulp cells were then treated with IGF-1 at different concentrations, and cell proliferation was detected by MTT assay after 7 days. The dental pulp cells were treated with IGF-1 (100ng/mL) and LY294002 (10μmol/L) respectively or simultaneously for 7 days, and cell proliferation was detected by MTT assay after 7 days. ALP activity was detected after culture for 3, 5, 7 and 14 days. The protein expression of AKT and p-AKT was detected after culture for 7days. Results: IGF-1 showed Low expression in pulpitis. IGF-1 could significantly promote the proliferation of dental pulp cells in the concentration range of 20-100 ng/mL since 3rd day(P<0.05)with a dose- and time-dependent effect. LY294002 could inhibit the proliferation of dental pulp cells and alkaline phosphatase activity with time-dependence. IGF-1 could promote the expression of p-AKT protein, while LY294002 could reduce the effect of IGF-1 on the expression of p-AKT protein. Conclusion: IGF-1 can promote the proliferation and alkaline phosphatase activity of dental pulp cells in concentration and time dependence manner, which may be related to the PI3K/AKT signaling pathway.