Oxidized galectin-1 reduces lipopolysaccharide-induced increase of proinflammatory cytokine mRNA in cultured macrophages

ized galectin-1 reduces lipopolysaccharide-induced increase of proinflammatory cytokine mRNA in cultured macrophages Original Research (2890) Total Article Views Authors: Yukie Kogawa, Kou Nakajima, Kenichi Sasaguri, et al Published Date January 2011 Volume 2011:3 Pages 1 - 8 DOI: http://dx.doi.org/10.2147/CCIDE.S16066 Yukie Kogawa1, Kou Nakajima1, Kenichi Sasaguri1, Nobushiro Hamada2, Haruhisa Kawasaki3, Sadao Sato1, Toshihiko Kadoya4, Hidenori Horie5 1Department of Orthodontics, 2Department of Oral Microbiology, Kanagawa Dental College, Yokosuka; 3Keio University, Kanagawa; 4Maebashi Institute of Technology, Maebashi; 5Research Center of Brain and Oral Science, Kanagawa Dental College, Yokosuka, Japan Background: Periodontitis is prevalent in older humans. Limiting the inflammation associated with periodontitis may provide a therapy for this condition, because Gram-negative bacteria expressing lipopolysaccharide (LPS) have a key role in initiation of inflammation by activating macrophage functions. Because oxidized galectin-1 regulates macrophage functions in other systems, we sought to establish whether this galectin-1 mRNA is expressed in the oral cavity, and whether it could dampen LPS-induced macrophage activation in vitro. Methods: Using the reverse transcriptase polymerase chain reaction (RT-PCR), we measured galectin-1 mRNA expression to clarify its localization to rat gingival tissues and studied the effect of Porphyromonas gingivalis challenge on galectin-1 expression. Next, we tested the effects of adding oxidized galectin-1 to cultured LPS-activated peritoneal macrophages on mRNA expression of proinflammatory factors by RT-PCR and real-time RT-PCR. Results: We established that galectin-1 mRNA is expressed in gingival tissues and also showed that galectin-1 mRNA was significantly increased by challenge with P. gingivalis, indicating that galectin-1 may regulate oral inflammation. On the other hand, LPS 100 ng/mL in serum-containing medium induced macrophages to upregulate mRNA associated with a proinflammatory response, ie, interleukins 1β and 6, and inducible nitric oxide synthase. We showed that application of 0.1–10 ng/mL of oxidized galectin-1 to LPS-treated macrophages reduced the intense LPS-induced increase by serum in proinflammatory mRNA expression in a concentration-dependent manner. Furthermore, application of oxidized galectin-1 10 ng/mL to LPS-treated macrophages in serum-free medium also showed a similar effect on LPS activity. Conclusion: Oxidized galectin-1 restricts the proinflammatory actions of LPS, and this protein could limit the negative effects of inflammation.