Dietary Rutin Ameliorates Nanoparticle Zinc Oxide-Induced Toxicity in Mice by Potentiating Antioxidant Defense Mechanisms.

In animal production, nanoparticulate zinc oxide exhibits synergistic antibacterial efficacy coupled with growth-promoting effects, positioning itself as a novel antibiotic alternative with enhanced biosafety profiles. However, its dose-dependent toxicity poses challenges. Objective: The experimental design sought to quantify the protective effects of dietary rutin against zinc-overload-induced damage. Methods: A zinc-overload murine model was established by giving high-dose ZnO nanoparticles (HZn, 5000 mg/kg/day) for 21 days. Mice were then fed rutin at doses of 300, 600, or 1200 mg/kg. Body weight, relative organ indexes, zinc concentrations, serum enzyme activities, and tissue-level indicators of apoptosis, autophagy, mitochondrial function, and antioxidant capacity were measured. Results: The results showed that rutin could not reverse HZn-induced body weight decline but improved relative organ indexes in liver and kidney. It alleviated HZn-induced cell damage and enhanced antioxidant capacity in jejunum and serum through Nrf2 activation, without inhibiting HZn-induced zinc elevation. Conclusions: Rutin, especially at 600 mg/kg, can partially restore hepatic function and organ index and mitigate HZn-induced hepatic and jejunal injuries.