130
oxygen species and lipid peroxidation. FeO nanoparticles increase the DNA damage which was shown by Comet assay, and it was shown that the expression levels
of mRNA of caspase-3 and caspase-9 genes were higher (Ahamed et al. 2013).
5.3 Zinc Oxide Nanoparticles (ZnO Nanoparticles)
ZnO nanoparticles possess ultraviolet scattering, antibacterial, and antifungal properties. Because of bactericidal properties, they are commonly used on biomedical
applications and food packaging, and also cosmetics, textiles, and electronic products. Due to the increased Zn exposure, toxicity and safety of Zn nanoparticle are
challenges to use ZnO nanoparticles (Ng et al. 2017). Cytotoxicity mechanisms of
ZnO nanoparticles are not well understood. The generation of free radicals and
production of reactive oxygen species from the surface of ZnO are major components for cytotoxicity. When cells exposure to ZnO nanoparticles, defense systems
in cells are activated to remove or minimize the toxic effects of nanoparticles
(Namvar et al. 2015). Oxidative damage and antioxidant balance are important, if
the balance is destroyed, oxidative harm occurs (Poljsak et al. 2013) and can cause
cell death. Teng et al. examined the cytotoxicity of ZnO nanoparticles at various
concentrations in MRC5 cells and found a significant morphological change in ZnO
nanoparticle -treated MRC5 cells compared to control cells. They also observed the
association between ZnO nanoparticle-treated MRC5 cells and the release of LDH
in a dose-dependent manner, especially 50μg/mL ZnO nanoparticle exposure could
cause cell death. They also showed genotoxicity of ZnO nanoparticles. ZnO
nanoparticle s exposure causes reactive oxygen species production, leading to an
accumulation of 8-hydroxy-2′-deoxyguanosine (8-OHdG). Oxidative DNA damage
due to 8-OHdG accumulation was detected by the comet assay (Ng et al. 2017).
Exposure to ZnO nanoparticles in the acidic environment such as in the lung lining
fluid causes ZnO dissolution. This type of exposure provides the transient increases
in the concentration of Zn2+ ions and causes local toxicity. Inhalation exposure and
instillation ZnO nanoparticles of rats in a dose-dependent manner resulted in transient inflammation measured in the bronchoalveolar tissues. There are few studies
which have investigated neurotoxicity of ZnO. Vandebriel and De Jong administered ZnO nanoparticles (20–80 nm) intraperitoneally to rats (4 mg/kg bw) for
8 weeks (ip 20–80 nm/twice weekly) and showed that spatial learning and memory
ability were attenuated by alteration of synaptic plasticity in rats (Vandebriel and De
Jong 2012).
B. Karahalil
oxygen species and lipid peroxidation. FeO nanoparticles increase the DNA damage which was shown by Comet assay, and it was shown that the expression levels
of mRNA of caspase-3 and caspase-9 genes were higher (Ahamed et al. 2013).
5.3 Zinc Oxide Nanoparticles (ZnO Nanoparticles)
ZnO nanoparticles possess ultraviolet scattering, antibacterial, and antifungal properties. Because of bactericidal properties, they are commonly used on biomedical
applications and food packaging, and also cosmetics, textiles, and electronic products. Due to the increased Zn exposure, toxicity and safety of Zn nanoparticle are
challenges to use ZnO nanoparticles (Ng et al. 2017). Cytotoxicity mechanisms of
ZnO nanoparticles are not well understood. The generation of free radicals and
production of reactive oxygen species from the surface of ZnO are major components for cytotoxicity. When cells exposure to ZnO nanoparticles, defense systems
in cells are activated to remove or minimize the toxic effects of nanoparticles
(Namvar et al. 2015). Oxidative damage and antioxidant balance are important, if
the balance is destroyed, oxidative harm occurs (Poljsak et al. 2013) and can cause
cell death. Teng et al. examined the cytotoxicity of ZnO nanoparticles at various
concentrations in MRC5 cells and found a significant morphological change in ZnO
nanoparticle -treated MRC5 cells compared to control cells. They also observed the
association between ZnO nanoparticle-treated MRC5 cells and the release of LDH
in a dose-dependent manner, especially 50μg/mL ZnO nanoparticle exposure could
cause cell death. They also showed genotoxicity of ZnO nanoparticles. ZnO
nanoparticle s exposure causes reactive oxygen species production, leading to an
accumulation of 8-hydroxy-2′-deoxyguanosine (8-OHdG). Oxidative DNA damage
due to 8-OHdG accumulation was detected by the comet assay (Ng et al. 2017).
Exposure to ZnO nanoparticles in the acidic environment such as in the lung lining
fluid causes ZnO dissolution. This type of exposure provides the transient increases
in the concentration of Zn2+ ions and causes local toxicity. Inhalation exposure and
instillation ZnO nanoparticles of rats in a dose-dependent manner resulted in transient inflammation measured in the bronchoalveolar tissues. There are few studies
which have investigated neurotoxicity of ZnO. Vandebriel and De Jong administered ZnO nanoparticles (20–80 nm) intraperitoneally to rats (4 mg/kg bw) for
8 weeks (ip 20–80 nm/twice weekly) and showed that spatial learning and memory
ability were attenuated by alteration of synaptic plasticity in rats (Vandebriel and De
Jong 2012).
B. Karahalil