Serum Calcium-decreasing Factor, Caldecrin, Inhibits Osteoclast Differentiation by Suppression of NFATc1 Activity
Serum Calcium-decreasing Factor, Caldecrin, Inhibits Osteoclast Differentiation by Suppression of NFATc1 Activity
复制标题
DOI：
10.1074/jbc.m109.068742
复制
发表时间：
2010-08-13
影响因子：
4.8
通讯作者：
Tomomura, Akito
中科院分区：
文献类型：
--
作者：
Hasegawa, Hiroya;Kido, Seisui;Tomomura, Akito
Caldecrin/Chymotrypsin C是一种新的分泌型丝氨酸蛋白酶，最初是从胰腺中分离出来的一种血清降钙因子。在此之前，我们曾报道钙化蛋白抑制兔成熟破骨细胞的骨吸收活性(Tomomura，A.，Yamada，H.，Fujimoto，K.，Inaba，A.和Katoh，S.(2001)FEBS Lett)。508、454-458)。在此，我们研究了钙蛋白对巨噬细胞集落刺激因子和骨髓细胞单核/巨噬细胞系的核因子-kappaB受体激活剂(RANKL)诱导小鼠破骨细胞分化的影响。野生型和蛋白水解酶缺失突变体caldecrin剂量依赖性地抑制RANKL刺激的骨髓细胞抗酒石酸酸性磷酸酶阳性破骨细胞的形成。Caldecrin不影响单核/巨噬细胞系细胞的巨噬细胞集落形成或骨髓细胞培养中破骨细胞前体细胞的生成。Caldecrin抑制RANKL刺激的活化T细胞核因子胞浆1(NFATc1)mRNA在骨髓细胞中的积聚，NFATc1是破骨细胞分化的关键转录因子。Caldecrin还抑制RANKL诱导的RAW264.7单核/巨噬细胞系向破骨细胞的分化。Caldecrin降低RAW264.7细胞中NFATc1的转录活性，而同样参与破骨细胞分化的转录因子NF-kappa B和c-Fos的转录活性不受影响。Caldecrin抑制RANKL刺激的NFATc1核转位和钙/钙调蛋白依赖性磷酸酶钙调神经磷酸酶的活性。Caldecrin抑制刺激RANKL引起的磷脂酶C-γ1介导的钙振荡。Caldecrin还可减弱RANKL刺激的脾酪氨酸激酶(Syk)的磷酸化。综上所述，这些结果表明，Caldecrin通过阻止磷脂酶C-Gamma 1介导的钙振荡-钙调神经磷酸酶-NFATc1途径来抑制破骨细胞的生成，而不是其蛋白酶活性。
Caldecrin/chymotrypsin C is a novel secretory-type serine protease that was originally isolated as a serum calcium-decreasing factor from the pancreas. Previously, we reported that caldecrin suppressed the bone-resorbing activity of rabbit mature osteoclasts (Tomomura, A., Yamada, H., Fujimoto, K., Inaba, A., and Katoh, S. (2001) FEBS Lett. 508, 454-458). Here, we investigated the effects of caldecrin on mouse osteoclast differentiation induced by macrophage-colony stimulating factor and the receptor activator of NF-kappa B ligand (RANKL) from the monocyte/macrophage cell lineage of bone marrow cells. Wildtype and protease-deficient mutant caldecrin dose-dependently inhibited RANKL-stimulated tartrate-resistant acid phosphatase-positive osteoclast formation from bone marrow cells. Caldecrin did not affect macrophage colony formation from monocyte/macrophage lineage cells or osteoclast progenitor generation in cultures of bone marrow cells. Caldecrin inhibited accumulation of the RANKL-stimulated nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1) mRNA in bone marrow cells, which is a key transcription factor for the differentiation of osteoclasts. Caldecrin also suppressed RANKL-induced differentiation of the RAW264.7 monocyte/macrophage cell line into osteoclasts. Caldecrin reduced the transcriptional activity of NFATc1 in RAW264.7 cells, whereas those of NF-kappa B and c-Fos, which are also transcription factors involved in osteoclast differentiation, were unaffected. Caldecrin inhibited RANKL-stimulated nuclear translocation of NFATc1 and the activity of the calcium/calmodulin-dependent phosphatase, calcineurin. Caldecrin inhibited phospholipase C gamma 1-mediated Ca2+ oscillation evoked by RANKL stimulation. RANKL-stimulated phosphorylation of spleen tyrosine kinase (Syk) was also attenuated by caldecrin. Taken together, these results indicate that caldecrin inhibits osteoclastogenesis, without its protease activity, by preventing a phospholipase C gamma 1-mediated Ca2+ oscillation-calcineurin-NFATc1 pathway.