Differences in TLR9-dependent inhibitory effects of H(2)O(2)-induced IL-8 secretion and NF-kappa B/I kappa B-alpha system activation by genomic DNA from five Lactobacillus species

• Published in: Microbes and infection 2013-02, Vol.15 (2), p.96-104
• Main Authors: Hiramatsu, Yukihiro, Satho, Tomomitsu, Irie, Keiichi, Shiimura, Shota, Okuno, Takahiro, Sharmin, Tanjina, Uyeda, Saori, Fukumitsu, Yuki, Nakashima, Yukihiko, Miake, Fumio, Kashige, Nobuhiro
• Format: Article
• Language: English
• Subjects: Active Transport, Cell Nucleus; Anti-Inflammatory Agents - immunology; Caco-2 Cells; Cell Nucleus - drug effects; Cell Nucleus - pathology; DNA, Bacterial - genetics; DNA, Bacterial - immunology; Dose-Response Relationship, Drug; Escherichia coli - genetics; Escherichia coli - immunology; Genome, Bacterial; Humans; Hydrogen Peroxide - pharmacology; I-kappa B Proteins - immunology; I-kappa B Proteins - metabolism; Interleukin-8 - metabolism; Lactobacillus - genetics; Lactobacillus - immunology; NF-kappa B - immunology; NF-kappa B - metabolism; NF-KappaB Inhibitor alpha; Proteolysis; RNA Interference; Signal Transduction; Toll-Like Receptor 9 - immunology; Toll-Like Receptor 9 - metabolism
• ISSN: 1769-714X
• DOI: 10.1016/j.micinf.2012.11.003

Lactic acid bacteria (LAB) show anti-inflammatory effects, and their genomic DNA was identified as one of the anti-inflammatory components. Despite the differences in anti-inflammatory effects between live LAB dependent not only on genus but also species, this effect has not been compared at the genomic DNA level. We compared the anti-inflammatory effects of the genomic DNA from five Lactobacillus species-Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus gasseri, Lactobacillus plantarum, and Lactobacillus reuteri-using Caco-2 cells. To evaluate anti-inflammatory effects, decreases in H(2)O(2)-induced IL-8 secretion and inhibition of H(2)O(2)-induced NF-κB/IκB-α system activation were examined. All LAB genomic DNAs dose-dependently decreased H(2)O(2)-induced IL-8 secretion and inhibited H(2)O(2)-induced NF-κB/IκB-α system activation. Comparison of these effects between Lactobacillus species showed that the anti-inflammatory effects of L. acidophilus genomic DNA are lower than those of the other species. Furthermore, suppression of Toll-like receptor 9 (TLR9), a specific receptor of bacterial DNA, expression by RNAi abolished the decrease of H(2)O(2)-induced IL-8 secretion and inhibition of H(2)O(2)-induced NF-κB/IκB-α system activation by LAB genomic DNA. Our results demonstrated that the anti-inflammatory effects of genomic DNA differ between Lactobacillus species and TLR9 is one of the major pathways responsible for the anti-inflammatory effect of LAB genomic DNA.