Protective effects of thymoquinone and avenanthramides on titanium dioxide nanoparticles induced toxicity in Sprague-Dawley rats.

Abstract The protective effect of thymoquinone (TQ), the major active ingredient of Nigella sativa seeds, and avenanthramides (AVA) enriched extract of oats on titanium dioxide naonparticles (TiO 2 NPs) induced toxicity and oxidative stress in Sprague-Dawley (SD) rats was investigated. Sixty rats were divided into 6 equal groups. The first, second, third, fourth and fifth groups received TiO 2 NPs, TiO 2 NPs and TQ, TiO 2 NPs and AVA, TQ only, or AVA only for 6 weeks. The sixth group served as the control. Exposure to TiO 2 NPs resulted in increased liver enzyme markers, oxidative stress indices, tumor necrosis factor alpha (TNF-α) and DNA damage. Histopathological alterations were also observed in the liver, brain, lung, kidney, heart and testes. Co-administration of TQ and AVA with TiO 2 NPs decreased the level of liver enzymes, oxidative stress, TNF-α and DNA damage. Furthermore, TQ and AVA increased the total antioxidant and glutathione (GSH) levels. In conclusion, TiO 2 NPs induce hazardous effects in different organs and are closely related to oxidative stress. TQ and AVA have antioxidative and anti-inflammatory effect against the detrimental effect of TiO 2 NPs.