Programa de Pós-graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília, Brasília, DF, Brazil.
Curso de Odontologia, Universidade Católica de Brasília, Brasília, DF, Brazil.
Clin Oral Investig. 2021 Apr;25(4):1805-1814. doi: 10.1007/s00784-020-03483-2. Epub 2020 Aug 12.
To evaluate the effect(s) of mineral trioxide aggregate (MTA) on in vitro RANKL-mediated osteoclast-dependent bone resorption events and the influence of Ca and Al on the osteoclastogenesis inhibition by MTA.
Two types of osteoclast precursors, RAW 264.7 (RAW) cell line or bone marrow cells (obtained from BALB/c mice and stimulated with recombinant (r) macrophage colony stimulation factor (M-CSF), were stimulated with or without recombinant (r) activator of nuclear kappa B ligand (RANKL), in the presence or absence of MTA for 6 to 8 days. White Angelus MTA and Bios MTA (Angelus, Londrina, Paraná, Brazil) were prepared and inserted into capillary tubes (direct contact surface = 0.50 mm and 0.01 mm). Influence of MTA on these types of osteoclast precursors was measured by the number of differentiated tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cells (RAW and bone marrow cells), TRAP enzyme activity (RAW cells), cathepsin K gene expression (RAW cells), and resorptive pit formation (RAW cells) by mature osteoclasts. Besides, RAW cells were also stimulated with Ca and Al to evaluate the influence of these ions on MTA anti-osteoclastogenic potential.
In bone marrow and RAW cells, the number of TRAP-positive mature osteoclast cells induced by rRANKL was significantly inhibited by the presence of MTA compared with control rRANKL stimulation without MTA (p < 0.05), along with the reduction of TRAP enzyme activity (p < 0.05) and the low expression of cathepsin K gene (p < 0.05). In contrast, to control mature osteoclasts, the resorption area on dentin was significantly decreased for mature osteoclasts incubated with MTA (p < 0.05). rRANKL-stimulated RAW cells treated with Ca and Al decreased the number of osteoclasts cells. Besides, the aluminum oxide was the dominant suppressor of the osteoclastogenesis process.
MTA significantly suppressed RANKL-mediated osteoclastogenesis and osteoclast activity and, therefore, appears able to suppress bone resorption events in periapical lesions. This process might be related to Ca and Al activities.
MTA is an important worldwidely acknowleged biomaterial. The knowledge about its molecular activities on osteoclasts might contribute to improving the understanding of its clinical efficacy.
评估三氧化矿物凝聚体（MTA）对体外核因子-κB 受体激活配体（RANKL）介导的破骨细胞依赖性骨吸收事件的影响，以及钙和铝对 MTA 抑制破骨细胞生成的影响。
使用 RAW 264.7（RAW）细胞系或骨髓细胞（来自 BALB/c 小鼠并经重组（r）巨噬细胞集落刺激因子（M-CSF）刺激）作为两种破骨细胞前体，在存在或不存在 MTA 的情况下，分别用或不用 rRANKL 刺激 6 至 8 天。将 White Angelus MTA 和 Bios MTA（Angelus，Londrina，Paraná，巴西）制备并插入毛细管（直接接触面积分别为 0.50mm 和 0.01mm）。通过检测分化的抗酒石酸酸性磷酸酶（TRAP）阳性多核细胞（RAW 和骨髓细胞）、TRAP 酶活性（RAW 细胞）、组织蛋白酶 K 基因表达（RAW 细胞）和成熟破骨细胞形成的吸收凹坑数（RAW 细胞），来测量 MTA 对这两种破骨细胞前体的影响。此外，还刺激 RAW 细胞以评估这些离子对 MTA 抗破骨细胞生成潜力的影响。
在骨髓和 RAW 细胞中，与无 MTA 的 rRANKL 刺激对照组相比，rRANKL 诱导的 TRAP 阳性成熟破骨细胞数量明显被 MTA 抑制（p<0.05），同时 TRAP 酶活性降低（p<0.05）和组织蛋白酶 K 基因表达降低（p<0.05）。相比之下，与对照成熟破骨细胞相比，用 MTA 孵育的成熟破骨细胞在牙本质上的吸收面积明显减少（p<0.05）。用 Ca 和 Al 处理的 rRANKL 刺激的 RAW 细胞减少了破骨细胞的数量。此外，氧化铝是破骨细胞生成过程的主要抑制剂。
MTA 显著抑制 RANKL 介导的破骨细胞生成和破骨细胞活性，因此似乎能够抑制根尖周病变中的骨吸收事件。该过程可能与 Ca 和 Al 的活性有关。
MTA 是一种重要的全球公认的生物材料。对其在破骨细胞上的分子活性的了解可能有助于提高对其临床疗效的理解。
