8-Nitroguanine formation in the liver of hamsters infected with Opisthorchis viverrini

• DOI: 10.1016/j.bbrc.2003.08.039
• Publication Date: 2003-09-11T23:30:03Z
• Authors: Somchai Pinlaor; Puangrat Yongvanit; Yusuke Hiraku; Ning Ma; Reiji Semba; Shinji Oikawa; Mariko Murata; Banchob Sripa; Paiboon Sithithaworn; Shosuke Kawanishi
• Keywords: Opisthorchis viverrini; Deoxyguanosine; Reactive nitrogen species

Nucleic acid damage by reactive nitrogen and oxygen species may contribute to the carcinogenesis associated with chronic infection and inflammation. We examined 8-nitroguanine and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) formation and nitric oxide (NO) production in hamsters infected with Opisthorchis viverrini (OV). Formation of 8-nitroguanine was assessed immunohistochemically with an antibody specific for 8-nitroguanine. 8-nitroguanine formation was found mainly in the cytoplasm and slightly in the nucleus of inflammatory cells and epithelial lining of bile duct at inflammatory areas in the liver. 8-nitroguanine immunoreactivity reached the highest intensity on day 30. A time profile of 8-nitroguanine formation was closely associated with that of plasma nitrate/nitrite. HPLC with an electrochemical detector revealed that the amount of 8-oxodG in the liver reached the maximal level on day 21. The mechanisms of 8-oxodG and 8-nitroguanine formation via O2*- and NO production triggered by OV infection were discussed in relation to cholangiocarcinoma development.