Rescue of a cherubism bone marrow stromal culture phenotype by reducing TGFβ signaling.
Rescue of a cherubism bone marrow stromal culture phenotype by reducing TGFβ signaling.
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通过减少 TGFβ 信号来拯救天使骨髓基质培养表型。
DOI：
10.1016/j.bone.2018.03.009
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发表时间：
2018
期刊：
影响因子：
4.1
通讯作者：
Maye,Peter
中科院分区：
文献类型：
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作者：
Liu,Yaling;Sharma,Tulika;Chen,I-Ping;Reichenberger,Ernst;Ueki,Yasuyoshi;Arif,Yumna;Parisi,Daniel;Maye,Peter
我们利用骨髓基质培养系统研究了巨结肠症小鼠模型（Sh 3bp 2KI/KI）中TGFβ信号转导的变化。有趣的是，来自巨像症小鼠的骨髓培养物不仅显示成骨细胞分化受损，而且还具有自发的破骨细胞形成。与野生型细胞相比，巨结肠症CD 11b −、CD 45 −细胞中TGFβ信号传导的靶基因PAI 1的表达升高2倍，而TGFβ信号传导抑制剂BAMBI的表达下调。我们还发现，用TGFβ信号通路的拮抗剂处理巨像培养物可以在很大程度上挽救成骨细胞分化，并显著减少自发破骨细胞形成。用I型TGFβ受体小分子抑制剂SB 505124处理使成骨细胞报告基因Col 1a 1 -2.3的表达增加了24倍，使成骨细胞基因标记物Osterix（Sp 7）的表达增加了25倍，骨唾液蛋白（BSP）的表达增加了7倍，骨钙素（Bglap 1）的表达增加了100倍，牙本质基质蛋白1（DMP 1）的表达增加了35倍。相比之下，SB 505124处理导致破骨细胞数量和大小显著减少。与野生型培养物相比，来自Sh 3bp 2KI/KImice的成骨细胞培养物中RANKL（破骨细胞形成的正调节因子）的基因表达分析高2.5倍，而RANKL抑制剂OPG低5倍。然而，SB 505124处理使RANKL几乎下降至野生型水平，同时增加OPG表达。我们的研究还暗示TGFβ配体在巨颌症病因学中的作用。用单克隆抗体1D 11阻断TGFβ配体可使来源于Sh 3bp 2KI/+和Sh 3bp 2KI/KImice的培养物中Col 1a 1 -2.3报告基因表达分别增加4倍和13倍。与野生型同窝仔相比，SH 3BP 2KI/KImice中潜伏性TGFβ1的血清水平也高2倍。总之，这些研究提供了证据，表明TGFβ信号传导水平升高可能导致巨颌症的疾病表型，并且途径活性降低可能是治疗这种罕见疾病的有效治疗方法。
We utilized a bone marrow stromal culture system to investigate changes in TGFβ signaling in a mouse model for cherubism (Sh3bp2KI/KI). Interestingly, bone marrow cultures derived from cherubism mice not only displayed impaired osteoblast differentiation, but also had spontaneous osteoclast formation. PAI1, a target gene of TGFβ signaling, was elevated 2-fold in cherubism CD11b−,CD45−cells compared to wild type cells, while the expression of BAMBI, an inhibitor of TGFβ signaling, was down-regulated. We also discovered that treatment of cherubism cultures with antagonists of the TGFβ signaling pathway could largely rescue osteoblast differentiation and markedly reduce spontaneous osteoclast formation. Treatment with the type I TGFβ receptor small molecule inhibitor SB505124 increased osteoblast reporter geneCol1a1-2.3 expression 24-fold and increased the expression of osteoblast gene markersOsterix(Sp7) 25-fold, Bone Sialoprotein (BSP) 7-fold, Osteocalcin (Bglap1) 100-fold, andDentinMatrix Protein1(DMP1) 35-fold. In contrast, SB505124 treatment resulted in a significant reductions in osteoclast number and size. Gene expression analyses for RANKL, a positive regulator of osteoclast formation was 2.5-fold higher in osteoblast cultures derived fromSh3bp2KI/KImice compared to wild type cultures, whereas OPG, an inhibitor of RANKL was 5-fold lower. However, SB505124 treatment reduced RANKL almost back down to wild type levels, while increasing OPG expression. Our studies also implicate a role for TGFβ ligands in the etiology of cherubism. Blocking of TGFβ ligands with the monoclonal antibody 1D11 increasedCol1a1-2.3 reporter expression 4-fold and 13-fold in cultures derived fromSh3bp2KI/+andSh3bp2KI/KImice, respectively. Serum levels of latent TGFβ1 were also 2-fold higher inSH3BP2KI/KImice compared to wild type littermates. Taken together, these studies provide evidence that elevated levels of TGFβ signaling may contribute to the disease phenotype of cherubism and a reduction in pathway activity may be an effective therapeutic approach to treat this rare disease.