Yeon Jeong-Tae, Choi Sik-Won, Kim Seong Hwan
Research Institute of Basic Science, Sunchon National, University, Suncheon 540‑742, Republic of Korea.
Amino Acids. 2016 Feb;48(2):559-65. doi: 10.1007/s00726-015-2112-0.
Arginase 1 (Arg1) limits the availability of l-arginine for producing nitric oxide (NO) and ornithine, a substrate for polyamine synthesis. Anti-osteoclastogenic activities of NO and polyamines, and the involvement of Arg1 on the dendritic cell differentiation of dendritic cells have been reported, but the relevance of Arg1 to osteoclast differentiation has not been investigated. Here, we observed Arg1 down-regulation during the RANKL-induced differentiation of bone marrow-derived macrophages into osteoclasts. Arg1 overexpression significantly inhibited osteoclast differentiation with low NO production, while Arg1 knockdown enhanced osteoclast differentiation with high NO production. These results suggest that Arg1 and NO have reciprocal roles as negative and positive regulators, respectively, of osteoclast differentiation. We conclude that Arg1 is down-regulated during osteoclast differentiation and may negatively regulate osteoclast differentiation by regulating NO production.
精氨酸酶1（Arg1）限制了用于生成一氧化氮（NO）和鸟氨酸（多胺合成的一种底物）的L-精氨酸的可用性。已有报道称NO和多胺具有抗破骨细胞生成活性，以及Arg1参与树突状细胞的树突状细胞分化，但尚未研究Arg1与破骨细胞分化的相关性。在此，我们观察到在RANKL诱导骨髓来源的巨噬细胞分化为破骨细胞的过程中Arg1表达下调。Arg1过表达显著抑制破骨细胞分化，同时NO生成量较低，而敲低Arg1则增强破骨细胞分化，同时NO生成量较高。这些结果表明，Arg1和NO分别作为破骨细胞分化的负性和正性调节因子发挥相互作用。我们得出结论，在破骨细胞分化过程中Arg1表达下调，并且可能通过调节NO生成来负性调节破骨细胞分化。
