Wang Jianping, Li Jingfeng, Yang Liang, Zhou Yichi, Wang Yi
Department of Orthopedics, Zhongnan Hospital of Wuhan University Department of Orthopedics, Union Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
Medicine (Baltimore). 2017 Apr;96(17):e6637. doi: 10.1097/MD.0000000000006637.
Parathyroid hormone (PTH), an 84-amino acid peptide, is an endocrine hormone that is secreted by parathyroid glands. PTH performs important functions in calcium regulation and bone remodeling. The PTH (1-34) named teriparatide, a 34-amino acid peptide derived from the N-terminus of PTH, conserves most of the functions of PTH, specifically the osteogenic capability. However, teriparatide is only used by injection and exhibits short duration. In addition, this PTH could not thoroughly expose active sites. In this study, a novel PTH-related peptide (designated PTHrP-1) derived from the N-terminus of PTH was added into the complete medium at different concentrations of PTHrP-1 (0, 50, 100, and 200 ng/mL) to induce the MC3T3-E1 cells. PTHrP-1 was detected by high-performance liquid chromatography and matrix-assisted laser desorption/ionization-time-of-flight mass spectroscopy. Cell morphology, cell proliferation, alkaline phosphatase (ALP), and ALP activity, osteocalcin concentration, and collagen type I (Col-I), osteopontin (OPN), and osteocalcin (OCN) mRNA expression by RT-PCR and protein expression by western blotting were observed and detected. The purity of the PTHrP-1 was 95.14%, and the PTHrP-1 can induce MC3T3-E1 cells into osteoblasts, thus improving ALP activity and OCN concentration, and increasing Col-I, OPN, and OCN mRNA expression and protein expression in MC3T3-E1 cell cultures. The PTHrP-1 proved to be an ideal active peptide. In addition, the osteogenic ability of PTHrP-1 at 200 and 100 ng/mL concentrations was not significantly different but significantly higher than 50 and 0 ng/mL groups. Results indicate that PTHrP-1 is a kind of active peptides that exhibits good biocompatibility with MC3T3-E1 cells and could improve cell proliferation and osteogenic differentiation. Moreover, PTHrP-1, at the preferable concentration of 100 ng/mL, could effectively promote MC3T3-E1 cells into osteoblasts.
甲状旁腺激素（PTH）是一种由84个氨基酸组成的肽，是由甲状旁腺分泌的一种内分泌激素。PTH在钙调节和骨重塑中发挥重要作用。名为特立帕肽的PTH（1-34），是一种从PTH的N端衍生而来的34个氨基酸的肽，保留了PTH的大部分功能，特别是成骨能力。然而，特立帕肽仅用于注射，且作用持续时间短。此外，这种PTH不能充分暴露活性位点。在本研究中，将一种从PTH的N端衍生而来的新型PTH相关肽（命名为PTHrP-1）以不同浓度（0、50、100和200 ng/mL）添加到完全培养基中以诱导MC3T3-E1细胞。通过高效液相色谱和基质辅助激光解吸/电离飞行时间质谱检测PTHrP-1。通过RT-PCR观察和检测细胞形态、细胞增殖、碱性磷酸酶（ALP）及其活性、骨钙素浓度以及I型胶原（Col-I）、骨桥蛋白（OPN）和骨钙素（OCN）的mRNA表达，通过蛋白质印迹检测蛋白质表达。PTHrP-1的纯度为95.14%，PTHrP-1可将MC3T3-E1细胞诱导为成骨细胞，从而提高ALP活性和OCN浓度，并增加MC3T3-E1细胞培养物中Col-I、OPN和OCN的mRNA表达及蛋白质表达。结果证明PTHrP-1是一种理想的活性肽。此外，200和100 ng/mL浓度的PTHrP-1的成骨能力无显著差异，但显著高于50和0 ng/mL组。结果表明，PTHrP-1是一种与MC3T3-E1细胞具有良好生物相容性的活性肽，可促进细胞增殖和成骨分化。此外，100 ng/mL的适宜浓度的PTHrP-1可有效促进MC3T3-E1细胞向成骨细胞分化。
