Kase Yoichi, Ikari Takahiro, Sekiguchi Toshio, Sato Masayuki, Ogiso Shouzo, Kawada Tsuyoshi, Matsubara Shin, Satake Honoo, Sasayama Yuichi, Endo Masato, Kitamura Kei-Ichiro, Hattori Atsuhiko, Watanabe Takushi X, Maruyama Yusuke, Watanabe Yoshinari, Funahashi Hisayuki, Kambegawa Akira, Suzuki Nobuo
Noto Marine Laboratory, Institute of Nature and Environmental Technology, Kanazawa University, Noto-cho, Ishikawa 927-0553, Japan.
Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1, Seikadai, Seika-cho, Soraku-gun, Kyoto 619-0284, Japan.
Comp Biochem Physiol A Mol Integr Physiol. 2017 Sep;211:77-83. doi: 10.1016/j.cbpa.2017.06.007. Epub 2017 Jun 11.
The nucleotide sequence of a sardine preprocalcitonin precursor has been determined from their ultimobranchial glands in the present study. From our analysis of this sequence, we found that sardine procalcitonin was composed of procalcitonin amino-terminal cleavage peptide (N-proCT) (53 amino acids), CT (32 amino acids), and procalcitonin carboxyl-terminal cleavage peptide (C-proCT) (18 amino acids). As compared with C-proCT, N-proCT has been highly conserved among teleosts, reptiles, and birds, which suggests that N-proCT has some bioactivities. Therefore, both sardine N-proCT and sardine CT were synthesized, and their bioactivities for osteoblasts and osteoclasts were examined using our assay system with goldfish scales that consisted of osteoblasts and osteoclasts. As a result, sardine N-proCT (10M) activated osteoblastic marker enzyme activity, while sardine CT did not change. On the other hand, sardine CT (10 to 10M) suppressed osteoclastic marker enzyme activity, although sardine N-proCT did not influence enzyme activity. Furthermore, the mRNA expressions of osteoblastic markers such as type 1 collagen and osteocalcin were also promoted by sardine N-proCT (10M) treatment; however, sardine CT did not influence their expressions. The osteoblastic effects of N-proCT lack agreement. In the present study, we can evaluate exactly the action for osteoblasts because our scale assay system is very sensitive and it is a co-culture system for osteoblasts and osteoclasts with calcified bone matrix. Both CT and N-proCT seem to influence osteoblasts and osteoclasts and promote bone formation by different actions in teleosts.
在本研究中，已从沙丁鱼的鳃后腺中确定了沙丁鱼前降钙素原前体的核苷酸序列。通过对该序列的分析，我们发现沙丁鱼降钙素原由降钙素原氨基末端裂解肽（N-proCT）（53个氨基酸）、CT（32个氨基酸）和降钙素原羧基末端裂解肽（C-proCT）（18个氨基酸）组成。与C-proCT相比，N-proCT在硬骨鱼、爬行动物和鸟类中高度保守，这表明N-proCT具有一些生物活性。因此，合成了沙丁鱼N-proCT和沙丁鱼CT，并使用我们的由成骨细胞和破骨细胞组成的金鱼鳞片检测系统检测了它们对成骨细胞和破骨细胞的生物活性。结果，沙丁鱼N-proCT（10μM）激活了成骨细胞标记酶活性，而沙丁鱼CT没有变化。另一方面，沙丁鱼CT（10至10μM）抑制了破骨细胞标记酶活性，尽管沙丁鱼N-proCT不影响酶活性。此外，沙丁鱼N-proCT（10μM）处理也促进了成骨细胞标记物如I型胶原和骨钙素的mRNA表达；然而，沙丁鱼CT不影响它们的表达。N-proCT的成骨作用缺乏一致性。在本研究中，我们能够准确评估其对成骨细胞的作用，因为我们的鳞片检测系统非常敏感，并且它是一个有成骨细胞和破骨细胞以及钙化骨基质的共培养系统。在硬骨鱼中，CT和N-proCT似乎都通过不同的作用影响成骨细胞和破骨细胞并促进骨形成。
