Assessment of the Oxidative Damage and Genotoxicity of Titanium Dioxide Nanoparticles and Exploring the Protective Role of Holy Basil Oil Nanoemulsions in Rats

This study was designed to evaluate the oxidative damage, genotoxicity, and DNA damage in the liver of rats treated with titanium nanoparticles (TiO 2 -NPs) with an average size of 28.0 nm and ξ -potential of − 33.97 mV, and to estimate the protective role of holy basil essential oil nanoemulsion (HBEON). Six groups of Male Sprague–Dawley rats were treated orally for 3 weeks as follows: the control group, HBEO or HBEON-treated groups (5 mg/kg b.w), TiO 2 -NPs-treated group (50 mg/kg b.w), and the groups treated with TiO 2 -NPs plus HBEO or HBEON. Samples of blood and tissues were collected for different analyses. The results revealed that 55 compounds were identified in HBEO, and linalool and methyl chavicol were the major compounds (53.9%, 12.63%, respectively). HBEON were semi-round with the average size and ζ -potential of 120 ± 4.5 nm and − 28 ± 1.3 mV, respectively. TiO 2 -NP administration increased the serum biochemical indices, oxidative stress markers, serum cytokines, DNA fragmentation, and DNA breakages; decreased the antioxidant enzymes; and induced histological alterations in the liver. Co-administration of TiO 2 -NPs plus HBEO or HBEON improved all the tested parameters and the liver histology, and HBEON was more effective than HBEO. Therefore, HEBON is a promising candidate able to protect against oxidative damage, disturbances in biochemical markers, gene expression, DNA damage, and histological changes resulting from exposure to TiO 2 -NPs and may be applicable in the food and pharmaceutical sectors.