Yahara Motoki, Tei Kanchu, Tamura Masato
Department of Biochemistry and Molecular Biology, Graduate School of Dental Medicine, Hokkaido University, Sapporo, Hokkaido 060‑8586, Japan.
Department of Oral and Maxillofacial Surgery, Graduate School of Dental Medicine, Hokkaido University, Sapporo, Hokkaido 060‑8586, Japan.
Mol Med Rep. 2017 Sep;16(3):2779-2784. doi: 10.3892/mmr.2017.6866. Epub 2017 Jun 27.
Neuropeptide Y (NPY) is a major neural signaling molecule. NPY is produced by peripheral tissues, such as osteoblasts, and binds to the corresponding Y1 receptor that belongs to the G‑protein‑coupled receptor family. Osteoblast‑specific Y1 receptor knockout mice exhibit high bone mass, indicating a role of the NPY‑Y1 receptor axis in the regulation of bone homeostasis. In the bone microenvironment, peripheral nerve fibers and osteoblasts produce NPY. However, the effects of the Y1 receptor on osteoblasts remain unexplored. In the present study, an RNA interference approach was employed to target the Y1 receptor, in order to determine whether it may function to regulate the growth, differentiation and viability of osteoblasts. Knockdown of the Y1 receptor by small interfering RNA (siRNA) lead to induction of alkaline phosphatase (ALP) activity and mineralization in mouse MC3T3‑E1 osteoblast cells. In addition, the mRNA expression levels of ALP, osteocalcin, collagen (I) α1, and bone sialoprotein were significantly increased following transfection of a Y1 receptor siRNA. Furthermore, the mRNA expression levels of Runx2 and osterix were significantly increased; however, no significant alterations in cell proliferation and caspase‑3/7 activity were observed in Y1 receptor siRNA‑transfected cells when compared with non‑targeting controls. The results demonstrate that Y1 receptor inhibition may increase osteoblastic differentiation, which indicates a role of the Y1 receptor in the regulation of osteoblastic differentiation.
神经肽Y（NPY）是一种主要的神经信号分子。NPY由外周组织如成骨细胞产生，并与属于G蛋白偶联受体家族的相应Y1受体结合。成骨细胞特异性Y1受体敲除小鼠表现出高骨量，表明NPY - Y1受体轴在骨稳态调节中起作用。在骨微环境中，外周神经纤维和成骨细胞产生NPY。然而，Y1受体对成骨细胞的影响仍未得到探索。在本研究中，采用RNA干扰方法靶向Y1受体，以确定其是否可能调节成骨细胞的生长、分化和活力。小干扰RNA（siRNA）敲低Y1受体导致小鼠MC3T3 - E1成骨细胞中碱性磷酸酶（ALP）活性和矿化的诱导。此外，转染Y1受体siRNA后，ALP、骨钙素、胶原蛋白（I）α1和骨唾液蛋白的mRNA表达水平显著增加。此外，Runx2和osterix的mRNA表达水平也显著增加；然而，与非靶向对照相比，在Y1受体siRNA转染的细胞中未观察到细胞增殖和caspase - 3/7活性的显著变化。结果表明，Y1受体抑制可能增加成骨细胞分化，这表明Y1受体在成骨细胞分化调节中起作用。
