Division of Oral Biology and Disease Control, Department of Periodontology, Osaka University Graduate School of Dentistry, Yamadaoka, Suita, Osaka, Japan.
J Periodontal Res. 2012 Oct;47(5):563-71. doi: 10.1111/j.1600-0765.2012.01467.x. Epub 2012 Feb 20.
Adiponectin is a cytokine constitutively produced by adipocytes and exhibits multiple biological functions by targeting various cell types. However, the effects of adiponectin on primary gingival fibroblasts and periodontal ligament cells are still unexplored. Therefore, we investigated the effects of adiponectin on gingival fibroblasts and periodontal ligament cells.
The expression of adiponectin receptors (AdipoR1 and AdipoR2) on human gingival fibroblasts (HGFs), mouse gingival fibroblasts (MGFs) and human periodontal ligament (HPDL) cells was examined using RT-PCR and western blotting. HGFs and MGFs were stimulated with interleukin (IL)-1β in the presence or absence of adiponectin, and the expression of IL-6 and IL-8 at both mRNA and protein levels was measured by real-time PCR and ELISA, respectively. Furthermore, small interfering RNAs (siRNAs) in MGFs were used to knock down the expression of mouse AdipoR1 and AdipoR2. The effects of adiponectin on the expression of alkaline phosphatase (ALP) and runt-related transcription factor 2 (Runx2) genes were evaluated by real-time PCR. Mineralized nodule formation of adiponectin-treated HPDL cells was revealed by Alizarin Red staining.
AdipoR1 and AdipoR2 were expressed constitutively in HGFs, MGFs and HPDL cells. Adiponectin decreased the expression of IL-6 and IL-8 in IL-1β-stimulated HGFs and MGFs. AdipoR1 siRNA in MGFs revealed that the effect of adiponectin on reduction of IL-6 expression was potentially mediated via AdipoR1. Adiponectin-treated HPDL cells promoted the expression of ALP and Runx2 mRNAs and up-regulated ALP activity. Furthermore, adiponectin enhanced mineralized nodule formation of HPDL cells.
Our observations demonstrate that adiponectin exerts anti-inflammatory effects on HGFs and MGFs, and promotes the activities of osteoblastogenesis of HPDL cells. We conclude that adiponectin has potent beneficial functions to maintain the homeostasis of periodontal health, improve periodontal lesions, and contribute to wound healing and tissue regeneration.
脂联素是脂肪细胞持续产生的细胞因子，通过靶向各种细胞类型发挥多种生物学功能。然而，脂联素对原代牙龈成纤维细胞和牙周韧带细胞的作用尚不清楚。因此，我们研究了脂联素对牙龈成纤维细胞和牙周韧带细胞的作用。
采用 RT-PCR 和 Western blot 检测人牙龈成纤维细胞（HGFs）、小鼠牙龈成纤维细胞（MGFs）和人牙周韧带（HPDL）细胞中脂联素受体（AdipoR1 和 AdipoR2）的表达。用白细胞介素（IL）-1β刺激 HGFs 和 MGFs，在存在或不存在脂联素的情况下，分别用实时 PCR 和 ELISA 检测 IL-6 和 IL-8 的 mRNA 和蛋白水平的表达。此外，用 MGFs 的小干扰 RNA（siRNA）敲低小鼠 AdipoR1 和 AdipoR2 的表达。用实时 PCR 评估脂联素对碱性磷酸酶（ALP）和 runt 相关转录因子 2（Runx2）基因表达的影响。用茜素红染色显示脂联素处理的 HPDL 细胞形成的矿化结节。
AdipoR1 和 AdipoR2 在 HGFs、MGFs 和 HPDL 细胞中持续表达。脂联素降低了 IL-1β刺激的 HGFs 和 MGFs 中 IL-6 和 IL-8 的表达。MGFs 中的 AdipoR1 siRNA 表明，脂联素降低 IL-6 表达的作用可能是通过 AdipoR1 介导的。脂联素处理的 HPDL 细胞促进了 ALP 和 Runx2 mRNA 的表达，并上调了 ALP 活性。此外，脂联素增强了 HPDL 细胞的矿化结节形成。
我们的观察结果表明，脂联素对 HGFs 和 MGFs 具有抗炎作用，并促进 HPDL 细胞成骨细胞活性。我们得出结论，脂联素具有强大的有益功能，可维持牙周健康的稳态，改善牙周病变，并有助于伤口愈合和组织再生。
