Kaempferol inhibits P. intermedia lipopolysaccharide-induced production of nitric oxide through translational regulation in murine macrophages: critical role of heme oxygenase-1-mediated ROS reduction

• Published in: Journal of periodontology (1970) Vol. 84; no. 4; p. 545
• Main Authors: Choi, In Soon, Choi, Eun-Young, Jin, Ji-Young, Park, Hae Ryoun, Choi, Jeom-Il, Kim, Sung-Jo
• Format: Journal Article
• Language: English
• Published: United States 01.04.2013
• Subjects: Animals; Cell Line; Heme Oxygenase-1 - physiology; Kaempferols - pharmacology; Lipopolysaccharides - antagonists & inhibitors; Macrophages - metabolism; Mice; Nitric Oxide - antagonists & inhibitors; Nitric Oxide - biosynthesis; Nitric Oxide Synthase Type II - antagonists & inhibitors; Nitric Oxide Synthase Type II - biosynthesis; Prevotella intermedia - metabolism; Protein Modification, Translational - drug effects; Reactive Oxygen Species - antagonists & inhibitors
• ISSN: 1943-3670
• DOI: 10.1902/jop.2012.120180

Nitric oxide (NO) could be a potential target for the development of new therapeutic approaches to the treatment of periodontal disease because this molecule plays a significant role in the tissue destruction observed in periodontitis. In this study, the authors investigate the effect of kaempferol on the production of NO by murine macrophage-like RAW264.7 cells stimulated with lipopolysaccharide (LPS) from Prevotella intermedia, a pathogen implicated in periodontal disease, and try to determine the underlying mechanisms of action. NO production was assayed by measuring the accumulation of nitrite in culture supernatants. Real-time polymerase chain reaction was performed to quantify inducible NO synthase (iNOS) and heme oxygenase-1 (HO-1) mRNA expression. iNOS and HO-1 protein expression and phosphorylation of c-Jun N-terminal kinase and p38 were characterized via immunoblot analysis. Reactive oxygen species (ROS) production was measured using the redox-sensitive fluorescent probe 2',7'-dichlorodihydrofluorescein diacetate. Kaempferol significantly inhibited NO production and expression of iNOS protein in P. intermedia LPS-stimulated RAW246.7 cells without affecting iNOS mRNA expression. Kaempferol upregulated HO-1 expression in LPS-activated cells. Inhibition of HO-1 activity by tin protoporphyrin IX (SnPP) abolished the suppressive effect of kaempferol on NO production. In addition, kaempferol significantly attenuated P. intermedia LPS-induced increase of intracellular ROS, and SnPP blocked this reduction. Treatment with antioxidants downregulated the production of LPS-induced NO. Kaempferol inhibits NO production and iNOS protein expression in P. intermedia LPS-stimulated RAW264.7 cells at the translational level via HO-1-mediated ROS reduction and could be an efficient modulator of host response in the treatment of periodontal disease.