Role of Transcription Factor Nrf2 in the Induction of Hepatic Phase 2 and Antioxidative Enzymes in vivo by the Cancer Chemoprotective Agent, 3H-1, 2-Dithiole-3-thione

作者：Mi‐Kyoung Kwak, Ken Itoh, Masayuki P. Yamamoto, Thomas R. Sutter, Thomas W. Kensler · 发表于：Molecular Medicine · 年份：2001 · DOI：10.1007/bf03401947 · 被引用次数：305 · 研究领域：Genomics, phytochemicals, and oxidative stress、Glutathione Transferases and Polymorphisms、Sulfur Compounds in Biology

The induction of phase 2 enzymes by dithiolethiones such as oltipraz is an effective means for achieving protection against environmental carcinogens in animals and humans. Transcriptional control of the expression of at least some of these protective enzymes is mediated through the antioxidant response element (ARE) found in the upstream regulatory region of many phase 2 genes. The transcription factor Nrf2, which binds to the ARE, appears to be essential for the induction of prototypical phase 2 enzymes such as glutathione S-transferase (GST) Ya, Yp, and NAD(P)H: quinone reductase (NQO1) in vivo. In the present study, 3 H -1,2-dithiole-3-thione (D3T) was used as a potent model inducer whose effects on gene expression and chemopreventive efficacy have been extensively characterized in the rat. Over a dozen putative D3T-inducible genes were examined in wild-type and nrf2 -disrupted mice by Northern blot hybridization and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis to elucidate whether loss of Nrf2 function also affects the induction of a broader representation of phase 2 and antioxidative enzymes. The effects of D3T on hepatic Nrf2 expression and localization were also examined in vivo by Northern blot hybridization, electromobility shift assay, and Western blot analysis. Specific activities of hepatic GST and NQO1 were increased by D3T in wild-type mice and were largely blunted in the nrf2 -deficient mice. However, changes in levels of RNA transcripts f...