School of Dentistry, College of Medicine, National Taiwan University Medical College and Department of Dentistry, National Taiwan University Hospital, Taipei, Taiwan.
School of Dentistry, Taipei Medical University, Taipei, Taiwan.
J Formos Med Assoc. 2017 Oct;116(10):748-754. doi: 10.1016/j.jfma.2017.07.008. Epub 2017 Aug 2.
BACKGROUND/PURPOSES: TGF-β1 is an important growth factor that may influence the odontoblast differentiation and matrix deposition in the reactionary/reparative dentinogenesis to dental caries or other tooth injuries. TGF-β1 exerts its effects through various signaling pathways, such as Smads and MAPKs. Cyclooxygenase-2 (COX-2) is a membrane-associated enzyme that produces prostaglandin E (PGE) at sites of pulpal injury and inflammation, which leads to tissue swelling, redness and pain. The purposes of this study were to investigate the differential signal transduction pathways of TGF-β1 that mediate COX-2 stimulation and PGE production in dental pulp cells.
Pulp cells were exposed to TGF-β1 with/without SB431542 (an ALK5/Smad2 inhibitor) and U0126 (a MEK/ERK inhibitor). MTT assay was used to estimate cell viability. Enzyme-linked immunosorbent assay (ELISA) was used for measurement of PGE levels. RT-PCR and western blot were used to determined COX-2 mRNA and protein, respectively.
Exposure to TGF-β1 (1-10 ng/ml) increased the COX-2 mRNA and protein level of cultured pulp cells. Exposure to TGF-β1 (0.1-10 ng/mL) significantly stimulated PGE production of dental pulp cells. Under the pretreatment of SB431542, the stimulatory effect of TGF-β1 on COX-2 level of pulp cells was inhibited. Similarly, U0126 also partly inhibited the TGF-β1-induced COX-2 expression.
TGF-β1 increased the COX-2 and PGE level of cultured pulp cells. The effect of TGF-β1 on COX-2 protein expression was associated with ALK5/Smad2/3 and MEK/ERK pathways. These events are important in the early inflammation, repair and regeneration of dental pulp in response to injury.
背景/目的：TGF-β1 是一种重要的生长因子，可能影响龋病或其他牙齿损伤反应性/修复性牙本质形成中的成牙本质细胞分化和基质沉积。TGF-β1 通过各种信号通路（如 Smads 和 MAPKs）发挥作用。环氧化酶-2（COX-2）是一种膜相关酶，在牙髓损伤和炎症部位产生前列腺素 E（PGE），导致组织肿胀、发红和疼痛。本研究旨在探讨 TGF-β1 介导的差异信号转导通路，该通路调节牙髓细胞中 COX-2 的刺激和 PGE 的产生。
用 TGF-β1 （有/无 SB431542（ALK5/Smad2 抑制剂）和 U0126（MEK/ERK 抑制剂）处理牙髓细胞。MTT 法估计细胞活力。酶联免疫吸附试验（ELISA）用于测量 PGE 水平。RT-PCR 和 Western blot 分别用于检测 COX-2 mRNA 和蛋白。
TGF-β1（1-10 ng/ml）暴露增加了培养牙髓细胞的 COX-2 mRNA 和蛋白水平。TGF-β1（0.1-10 ng/ml）显著刺激牙髓细胞 PGE 的产生。在 SB431542 的预处理下，TGF-β1 对牙髓细胞 COX-2 水平的刺激作用受到抑制。同样，U0126 也部分抑制了 TGF-β1 诱导的 COX-2 表达。
TGF-β1 增加了培养牙髓细胞的 COX-2 和 PGE 水平。TGF-β1 对 COX-2 蛋白表达的影响与 ALK5/Smad2/3 和 MEK/ERK 途径有关。这些事件在牙髓对损伤的早期炎症、修复和再生中很重要。
