Hospital of Stomatology, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, P. R. China.
Guangdong Province Key Laboratory of Stomatology, Guangzhou, Guangdong, P. R. China.
Mol Oral Microbiol. 2024 Jun;39(3):136-151. doi: 10.1111/omi.12425. Epub 2023 Jun 22.
This study aimed to investigate the effect of Stat3 on the osteoblast-mediated bone healing in the inflammatory lesion.
The conditional knockout of Stat3 in osteoblasts (Stat3 CKO) was generated via the Cre-loxP recombination system using Osterix-Cre transgenic mice. The calvarial bone inflammatory lesions were established on both Stat3 CKO and wild-type mice, then harvested to assess the bone healing. In response to lipopolysaccharide (LPS) stimulation, osteoblasts from Stat3 CKO and wild-type mice were subjected to examine the formation of calcium deposits, the expression of osteogenic markers (i.e., Runx2, OPN, COL1A1), and osteoclast-related markers (i.e., RANKL, OPG). The EdU and transwell assays were performed to assess the proliferation and migration of the cells.
A decrease in bone mass and an increase in osteolysis were found in the inflammatory lesions on Stat3 CKO mice when compared with the control. More osteoclastic-like cells and an increased expression of RANKL were observed in Stat3 CKO mice. Both mRNA and protein expressions of Stat3 and osteogenic markers in the lesions were significantly decreased in Stat3 CKO mice. After co-cultured with osteogenic medium, the Stat3-deficient osteoblasts were found with a significant decrease in calcium deposits and the expression of osteogenic markers, and with a significant increased expression of RANKL. The impaired ossification of Stat3-deficient osteoblasts was even more pronounced with the presence of lipopolysaccharides in vitro. The most decrease in cell proliferation and migration was found in Stat3-deficient osteoblasts in response to LPS.
Loss of Stat3 in osteoblasts impaired bone healing in an inflammatory microenvironment.
本研究旨在探讨 Stat3 在破骨细胞介导的炎症病变骨愈合中的作用。
通过 Cre-loxP 重组系统，利用 Osterix-Cre 转基因小鼠生成成骨细胞中 Stat3 的条件性敲除（Stat3 CKO）。在 Stat3 CKO 和野生型小鼠的双侧颅骨骨炎症病变中建立模型，然后进行骨愈合评估。用脂多糖（LPS）刺激 Stat3 CKO 和野生型小鼠的成骨细胞，检测钙沉积形成、成骨标志物（Runx2、OPN、COL1A1）和破骨细胞相关标志物（RANKL、OPG）的表达。通过 EdU 和 Transwell 检测来评估细胞的增殖和迁移。
与对照组相比，Stat3 CKO 小鼠炎症病变中的骨量减少，骨溶解增加。Stat3 CKO 小鼠中观察到更多的破骨细胞样细胞和 RANKL 表达增加。Stat3 CKO 小鼠病变中 Stat3 和成骨标志物的 mRNA 和蛋白表达均显著降低。与成骨培养基共培养后，发现 Stat3 缺失的成骨细胞钙沉积和成骨标志物表达显著减少，而 RANKL 表达显著增加。体外存在脂多糖时，Stat3 缺失的成骨细胞骨化受损更为明显。Stat3 缺失的成骨细胞对 LPS 的反应中细胞增殖和迁移减少最为明显。
成骨细胞中 Stat3 的缺失削弱了炎症微环境中的骨愈合。
