Ara Toshiaki, Fujinami Yoshiaki, Urano Hiroko, Hirai Kaname, Hatori Toshimi, Miyazawa Hiroo
Department of Pharmacology, Matsumoto Dental University, 1780 Gobara Hirooka, Shiojiri, Nagano 399-0781, Japan.
J Negat Results Biomed. 2012 Mar 27;11:10. doi: 10.1186/1477-5751-11-10.
Periodontal disease is accompanied by inflammation of the gingiva and destruction of periodontal tissues, leading to alveolar bone loss in severe clinical cases. Interleukin (IL)-6, IL-8, and the chemical mediator prostaglandin E₂ (PGE₂) are known to play important roles in inflammatory responses and tissue degradation. Recently, we reported that the protein kinase A (PKA) inhibitor H-89 suppresses lipopolysaccharide (LPS)-induced IL-8 production by human gingival fibroblasts (HGFs). In the present study, the relevance of the PKA activity and two PKA-activating drugs, aminophylline and adrenaline, to LPS-induced inflammatory cytokines (IL-6 and IL-8) and PGE₂ by HGFs were examined.
HGFs were treated with LPS from Porphyromonas gingivalis and H-89, the cAMP analog dibutyryl cyclic AMP (dbcAMP), aminophylline, or adrenaline. After 24 h, IL-6, IL-8, and PGE₂ levels were evaluated by ELISA.
H-89 did not affect LPS-induced IL-6 production, but suppressed IL-8 and PGE₂ production. In contrast, dbcAMP significantly increased LPS-induced IL-6, IL-8, and PGE₂ production. Up to 10 μg/ml of aminophylline did not affect LPS-induced IL-6, IL-8, or PGE₂ production, but they were significantly increased at 100 μg/ml. Similarly, 0.01 μg/ml of adrenaline did not affect LPS-induced IL-6, IL-8, or PGE₂ production, but they were significantly increased at concentrations of 0.1 and 1 μg/ml. In the absence of LPS, H-89, dbcAMP, aminophylline, and adrenaline had no relevance to IL-6, IL-8, or PGE₂ production.
These results suggest that the PKA pathway, and also PKA-activating drugs, enhance LPS-induced IL-6, IL-8, and PGE₂ production by HGFs. However, aminophylline may not have an effect on the production of these molecules at concentrations used in clinical settings (8 to 20 μg/ml in serum). These results suggest that aminophylline does not affect inflammatory responses in periodontal disease.
牙周病伴有牙龈炎症和牙周组织破坏，在严重临床病例中会导致牙槽骨丧失。已知白细胞介素（IL）-6、IL-8和化学介质前列腺素E₂（PGE₂）在炎症反应和组织降解中起重要作用。最近，我们报道蛋白激酶A（PKA）抑制剂H-89可抑制脂多糖（LPS）诱导的人牙龈成纤维细胞（HGFs）产生IL-8。在本研究中，检测了PKA活性以及两种PKA激活药物氨茶碱和肾上腺素与LPS诱导的HGFs产生炎症细胞因子（IL-6和IL-8）及PGE₂的相关性。
用牙龈卟啉单胞菌的LPS以及H-89、环磷酸腺苷类似物二丁酰环磷腺苷（dbcAMP）、氨茶碱或肾上腺素处理HGFs。24小时后，通过酶联免疫吸附测定（ELISA）评估IL-6、IL-8和PGE₂水平。
H-89不影响LPS诱导的IL-6产生，但抑制IL-8和PGE₂产生。相反，dbcAMP显著增加LPS诱导的IL-6、IL-8和PGE₂产生。高达10μg/ml的氨茶碱不影响LPS诱导的IL-
