Electron Microscopical Evidence of the Protective Function of Thioredoxin (TRX/ADF) Transgene against 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced Cellular Toxicity in the Liver and Brain

The present study was performed to assess the protective role of thioredoxin/adult T-cell leukemia-derived factor (TRX/ADF) on the liver and brain cell damages induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in ADF wild-type (WT) and transgenic (Tg) mice. The ADF WT and Tg mice were intraperitoneally injected with a single dose of TCDD (150 μg/kg body weight). One day after the treatment, the liver and brain tissues were examined electron microscopically to evaluate the cellular toxicity. In the ADF WT mice, marked reduction of subcellular components, such as mitochondria, rough endoplasmic reticula, and glycogen granules, as well as swelling of the remaining mitochondria, were evident in the liver cells. However, attenuation of these changes was evident in TCDD-treated TRX/ADF mice. Similar subcellular changes noted in the neuronal cells of TCDD-treated WT mice were also attenuated in Tg mice. The results suggest that oxidative cellular damage contributes to the acute toxicity induced by TCDD and that TRX/ADF protects against it.