Proteome-wide quantitative analysis of redox cysteine in porcine uterus reveals deoxynivalenol induced oxidative stress via protein hyperoxidation.

Deoxynivalenol (DON), a mycotoxin produced by fungi of the genus Fusarium, is ubiquitously distributed in feed and poses a substantial threat to human and animal health. Pigs exhibit particular sensitivity to DON, which can induce reproductive impairment. While the ovarian toxicity of DON has been extensively investigated, its effects on the uterus remain largely understudied. We established a DON-exposed piglet model and observed severe oxidative damage in the uterus. Reactive oxygen species (ROS) regulate protein function by catalyzing cysteine modifications in vivo. Employing mass spectrometry-based redox proteomics, we identified 17,882 cysteine thiol oxidation sites across 7147 DON-affected proteins, among which 150 sites on 130 proteins displayed significant alterations following DON exposure. Notably, multiple key members of antioxidant protein families, such as GPXs and PRDXs, underwent extensive oxidation themselves-a phenomenon that may be associated with reduced enzymatic activity, as validated by experimental results on glutathione reductase (GSR). Finally, in vitro experiments demonstrated that tea polyphenols, a natural antioxidant present in tea, can mitigate DON-induced damage to endometrial cell lines by alleviating protein hyperoxidation. Our study provides novel insights into the uterine toxicity of DON and the pervasive nature of redox modifications, while also identifying potential therapeutic targets.