Division of Periodontology, Department of Oral Interdisciplinary Medicine, Kanagawa Dental University, Yokosuka, Japan.
Division of Microbiology, Department of Oral Science, Kanagawa Dental University, Yokosuka, Japan.
J Periodontol. 2019 Aug;90(8):903-910. doi: 10.1002/JPER.18-0559. Epub 2019 Jun 2.
Porphyromonas gingivalis is a major pathogen and has a high detection rate in periodontal disease. Fimbriae and hemagglutinin are expressed by P. gingivalis, and these play an important role in the adherence of the bacteria to periodontal tissue and biofilm formation. The aim of this study was to investigate the effects of sub-minimal inhibitory concentrations (sub-MICs) of azithromycin on the adherence of P. gingivalis, focusing on the inhibition of fimbriae expression and hemagglutinin activity.
P. gingivalis ATCC 33277 were incubated anaerobically with sub-MICs of azithromycin at 37°C by gentle shaking for 18 hours. The bacterial cells were harvested, washed twice with phosphate-buffered saline (PBS), and the proteins analyzed by 12% sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting. Adherence assay and hemagglutinin activity tests were done with the same culture.
The results of SDS-PAGE indicated that the sub-MICs of azithromycin inhibited 41-kDa fimbrial protein expression and hemagglutinin activities. The disappearance of 41-kDa fimbrial protein expression and long fimbriae in 0.4 µg/mL, 0.2 µg/mL, and 0.1 µg/mL of azithromycin was confirmed by western blotting and transmission electron microscopy. The adherence of P. gingivalis to human gingival epithelial cells was reduced by sub-MICs of azithromycin compared with the adherence levels without antibiotic.
These results suggest that sub-MICs of azithromycin may reduce the adherence of P. gingivalis to host cells, by inhibiting production of fimbriae and hemagglutinin activities. Therefore, azithromycin can be used as a biofilm treatment of periodontal disease caused by P. gingivalis.
牙龈卟啉单胞菌是一种主要的病原体，在牙周病中有很高的检出率。菌毛和血凝素由牙龈卟啉单胞菌表达，这些在细菌与牙周组织的黏附和生物膜形成中起着重要作用。本研究旨在探讨亚最小抑菌浓度（sub-MICs）的阿奇霉素对牙龈卟啉单胞菌黏附的影响，重点关注菌毛表达和血凝素活性的抑制。
将牙龈卟啉单胞菌 ATCC 33277 在 37°C 下用亚 MICs 的阿奇霉素温和摇动孵育 18 小时。将细菌细胞收获，用磷酸盐缓冲盐水（PBS）洗涤两次，并用 12%十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）和 Western blot 分析蛋白质。用相同的培养物进行黏附试验和血凝素活性试验。
SDS-PAGE 结果表明，亚 MICs 的阿奇霉素抑制 41kDa 菌毛蛋白表达和血凝素活性。Western blot 和透射电镜证实，0.4μg/mL、0.2μg/mL 和 0.1μg/mL 阿奇霉素的亚 MICs 抑制了 41kDa 菌毛蛋白表达和长菌毛的产生。与无抗生素相比，亚 MICs 的阿奇霉素降低了牙龈卟啉单胞菌对人牙龈上皮细胞的黏附。
这些结果表明，亚 MICs 的阿奇霉素可能通过抑制菌毛的产生和血凝素活性，减少牙龈卟啉单胞菌对宿主细胞的黏附。因此，阿奇霉素可作为治疗由牙龈卟啉单胞菌引起的牙周病的生物膜。
