Could curcumin ameliorate titanium dioxide nanoparticles effect on the heart? A histopathological, immunohistochemical, and genotoxic study.

The evaluation of the toxicological effects of titanium dioxide nanoparticles (TiO2NPs) is increasingly important due to their growing occupational and industrial use. Curcumin is a yellow curry spice with a long history of use in herbal medicine and has numerous protective potentials such as antioxidant, antimicrobial, anti-inflammatory, and anti-apoptotic effects. Accordingly, we tested the hypothesis that curcumin could ameliorate TiO2NP-induced cardiotoxic and genotoxic effects in adult male albino rats. For this purpose, 48 adult male albino rats were randomized into five groups; all treatment was by oral gavage once daily for 90 days: group I (8 rats), untreated control; group II (16 rats), subdivided into vehicle control IIa (8 rats) received saline and vehicle control IIb (8 rats) received corn oil; group III (8 rats) orally gavaged with curcumin dissolved in 0.5 ml corn oil at a dose of 200 mg/kg b.w./day; group IV treated with TiO2NPs at a dose of 1200 mg/kg b.w./day (1/10 LD50) suspended in 1 ml of 0.9% saline; group V treated with curcumin + TiO2NPs (the same previously mentioned doses). Curcumin was orally gavaged for 7 days before TiO2NPs treatment was initiated, and then they received TiO2NPs along with curcumin at the same doses for 90 days. TiO2NPs administration resulted in several myocardial cytomorphic changes as structurally disorganized, degenerated, and apoptotic cardiomyocytes and the newly implemented 3-nitrotyrosine immune expression rendered strong evidence that these effects derived from the cardio myocellular oxidative burden. Furthermore, comet assay results confirmed TiO2NP-related DNA damage. Remarkably, all these changes are partially mitigated in rats treated with both curcumin and TiO2NPs. Our results suggest that concurrent curcumin treatment has a beneficial role in ameliorating TiO2NP-induced cardiotoxicity and this may be mediated by its antioxidative property.