Katono Tomoko, Kawato Takayuki, Tanabe Natsuko, Suzuki Naoto, Iida Takafumi, Morozumi Akira, Ochiai Kuniyasu, Maeno Masao
Nihon University Graduate School of Dentistry, 1-8-13 Kanda Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
Arch Oral Biol. 2008 Oct;53(10):903-9. doi: 10.1016/j.archoralbio.2008.02.016. Epub 2008 Apr 11.
Butyric acid (sodium butyrate; BA) is a major metabolic by-product of main periodontopathic bacteria present in subgingival plaque. In the present study, we examined the effects of BA on cell proliferation, alkaline phosphatase (ALPase) activity, mineralized nodule formation, extracellular matrix protein expression, macrophage colony-stimulating factor (M-CSF), and osteoprotegerin (OPG) in normal human osteoblasts.
The cells were cultured with 0, 10(-8), 10(-6) or 10(-4)M BA for up to 12 days. Mineralized nodule formation was detected by alizarin red staining, and the calcium content in mineralized nodules was determined using a calcium assay kit. The gene and protein expression levels for type I collagen, bone sialoprotein (BSP), osteopontin (OPN), M-CSF, and OPG were examined using real-time PCR and ELISA, respectively.
Mineralized nodule formation and the calcium content of mineralized nodules were increased by BA in a dose-dependent manner. Cell proliferation and ALPase activity were not affected by the addition of BA. Following the addition of 10(-4)M BA, the expression levels of BSP, OPN, and OPG increased, whereas the expression levels of type I collagen and M-CSF were not markedly affected.
These results suggest that BA stimulates bone formation by increasing the production of BSP and OPN, whereas it suppresses osteoclast differentiation by increasing the production of OPG by human osteoblasts.
丁酸（丁酸钠；BA）是龈下菌斑中主要牙周病原菌的主要代谢副产物。在本研究中，我们检测了BA对正常人成骨细胞的细胞增殖、碱性磷酸酶（ALPase）活性、矿化结节形成、细胞外基质蛋白表达、巨噬细胞集落刺激因子（M-CSF）和骨保护素（OPG）的影响。
将细胞分别用0、10⁻⁸、10⁻⁶或10⁻⁴M的BA培养长达12天。通过茜素红染色检测矿化结节形成，并使用钙测定试剂盒测定矿化结节中的钙含量。分别使用实时PCR和ELISA检测I型胶原蛋白、骨唾液蛋白（BSP）、骨桥蛋白（OPN）、M-CSF和OPG的基因和蛋白表达水平。
BA以剂量依赖性方式增加矿化结节形成和矿化结节中的钙含量。添加BA不影响细胞增殖和ALPase活性。添加10⁻⁴M BA后，BSP、OPN和OPG的表达水平升高，而I型胶原蛋白和M-CSF的表达水平未受到明显影响。
这些结果表明，BA通过增加BSP和OPN的产生来刺激骨形成，而通过增加人成骨细胞OPG的产生来抑制破骨细胞分化。
