Ozeki N, Yamaguchi H, Hiyama T, Kawai R, Nakata K, Mogi M, Nakamura H
Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Japan.
Oral Dis. 2015 Jan;21(1):97-105. doi: 10.1111/odi.12219. Epub 2013 Dec 30.
We previously reported that matrix metalloproteinase-3(MMP-3) accelerates wound healing following dental pulp injury. In this study, we tested the hypothesis that induction of MMP-3 activity by interleukin-1β would promote proliferation and apoptosis of dental pulp cells.
Dental pulp cells were isolated from rat incisors and subjected to interleukin-1β. Matrix metalloproteinase-3 mRNA and protein expression were assessed using reverse transcription-polymerase chain reaction and Western blotting, respectively. Matrix metalloproteinase-3 activity was measured using fluorescence. Dental pulp cell proliferation and apoptosis were determined using enzyme-linked immunosorbent assays (ELISA) for BrdU and DNA fragmentation, respectively. siRNA was used to reduce MMP-3 transcripts in these cells.
Treatment with interleukin-1β increased MMP-3 mRNA and protein levels as well as its activity in dental pulp cells. Cell proliferation was also markedly increased, with no changes in apoptosis observed. Treatment with siRNA against MMP-3 potently suppressed this interleukin-1β-induced increase in MMP-3 expression and activity, and also suppressed cell proliferation but unexpectedly increased apoptosis in these cells (P < 0.05). This siRNA-mediated increase in apoptosis could be reversed with exogenous MMP-3 stimulation (P < 0.05).
Interleukin-1β induces MMP-3-regulated cell proliferation and suppresses apoptosis in dental pulp cells.
我们之前报道过基质金属蛋白酶-3（MMP-3）可加速牙髓损伤后的伤口愈合。在本研究中，我们验证了白细胞介素-1β诱导MMP-3活性可促进牙髓细胞增殖和凋亡的假说。
从大鼠切牙中分离牙髓细胞，并使其接受白细胞介素-1β处理。分别使用逆转录-聚合酶链反应和蛋白质印迹法评估MMP-3 mRNA和蛋白表达。使用荧光法测定MMP-3活性。分别使用针对BrdU的酶联免疫吸附测定（ELISA）和DNA片段化测定牙髓细胞增殖和凋亡。使用小干扰RNA（siRNA）降低这些细胞中的MMP-3转录本。
白细胞介素-1β处理可增加牙髓细胞中MMP-3 mRNA和蛋白水平及其活性。细胞增殖也显著增加，未观察到凋亡变化。用针对MMP-3的siRNA处理可有效抑制白细胞介素-1β诱导的MMP-3表达和活性增加，还可抑制细胞增殖，但意外地增加了这些细胞中的凋亡（P<0.05）。这种siRNA介导的凋亡增加可通过外源性MMP-3刺激逆转（P<0.05）。
白细胞介素-1β诱导MMP-3调节的牙髓细胞增殖并抑制其凋亡。
