First Author | Yoshida H | Year | 2011 |
Journal | Free Radic Biol Med | Volume | 51 |
Issue | 2 | Pages | 424-31 |
PubMed ID | 21571065 | Mgi Jnum | J:174097 |
Mgi Id | MGI:5051883 | Doi | 10.1016/j.freeradbiomed.2011.04.035 |
Citation | Yoshida H, et al. (2011) Increase in CpG DNA-induced inflammatory responses by DNA oxidation in macrophages and mice. Free Radic Biol Med 51(2):424-31 |
abstractText | Unmethylated CpG dinucleotide (CpG motif) is involved in the exacerbation of DNA-associated autoimmune diseases. We investigated the effect of DNA containing 8-hydroxydeoxyguanosine (oxo-dG), a representative DNA biomarker for oxidative stress in the diseases, on CpG motif-dependent inflammatory responses. ODN1668 and ODN1720 were selected as CpG-DNA and non-CpG DNA, respectively. Deoxyguanosine in the CpG motif (G9) or outside the motif (G15) of ODN1668 was substituted with oxo-dG to obtain oxo(G9)-1668 and oxo(G15)-1668, respectively. Oxo(G15)-1668 induced a significantly higher amount of tumor necrosis factor (TNF)-alpha from RAW264.7 macrophage-like cells than ODN1668, whereas oxo(G9)-1668, oxo(G8)-1720, or oxo(G15)-1720 hardly did. CpG DNA-induced TNF-alpha production was significantly increased by addition of oxo(G8)-1720 or oxo(G15)-1720, but not of ODN1720. This oxo-dG-containing DNA-induced increase in TNF-alpha production was also observed in primary cultured macrophages isolated from wild-type mice, but not observed in those from Toll-like receptor (TLR)-9 knockout mice. In addition, TNF-alpha production by ligands for TLR3, TLR4, or TLR7 was not affected by oxo-dG-containing DNA. Then, the footpad swelling induced by subcutaneous injection of ODN1668 into mice was increased by coinjection with oxo(G8)-1720, but not with ODN1720. These results indicate that oxo-dG-containing DNA increases the CpG motif-dependent inflammatory responses, which would exacerbate DNA-related autoimmune diseases. |