The State Key Laboratory of Oral Diseases, Sichuan University, 14# 3rd section, Renmin South Road, Chengdu 610041, PR China.
Exp Cell Res. 2010 Apr 1;316(6):1019-27. doi: 10.1016/j.yexcr.2010.01.002. Epub 2010 Jan 11.
During the dental pulp repair process, dental pulp cells (DPCs) migrate to the site of injury and differentiate into odontoblasts or odontoblast-like cells. Although migration of DPCs is an important reparative process, the underlying mechanism remains unknown. The objective of this study was to determine the roles of lysophosphatidic acid (LPA) and the Rho-associated kinase (ROCK) pathway in the migration and morphology of dental pulp cells and alpha smooth muscle actin expression in vitro. We demonstrated that both LPA and ROCK inhibition enhanced cell motility and that their combined effects significantly increased migration rate. LPA induced fine cytoskeleton assembly and increased the level of alpha smooth muscle actin (alpha-SMA). ROCK inhibition by Y-27632 and ROCK-(1+2) small interfering RNA (siRNA) resulted in less actin cytoskeleton formation, a lower alpha-SMA level, a star-like cellular morphology and membrane ruffling. LPA and ROCK inhibition induced activation of another Rho GTPase, Rac, which may explain how LPA and ROCK inhibition increases cellmigration and lamellipodium formation.
在牙髓修复过程中，牙髓细胞（DPCs）迁移到损伤部位并分化为成牙本质细胞或成牙本质细胞样细胞。虽然 DPCs 的迁移是一个重要的修复过程，但其中的机制尚不清楚。本研究旨在确定溶血磷脂酸（LPA）和 Rho 相关激酶（ROCK）通路在牙髓细胞迁移和形态以及体外α平滑肌肌动蛋白表达中的作用。我们证明，LPA 和 ROCK 抑制均增强了细胞的迁移能力，并且它们的联合作用显著增加了迁移率。LPA 诱导精细的细胞骨架组装并增加α平滑肌肌动蛋白（α-SMA）的水平。Y-27632 和 ROCK-（1+2）小干扰 RNA（siRNA）抑制 ROCK 导致较少的肌动蛋白细胞骨架形成，α-SMA 水平较低，细胞呈星状形态和细胞膜皱襞。LPA 和 ROCK 抑制诱导另一种 Rho GTPase Rac 的激活，这可能解释了 LPA 和 ROCK 抑制如何增加细胞迁移和片状伪足形成。
