Retinopathy Induced by Zinc Oxide Nanoparticles in Rats Assessed by Micro-computed Tomography and Histopathology

Lee

et al. 2019

ToxicolRes

Nanoparticles (NPs) have been recognized as both useful tools and potentially toxic materials in various industrial and medicinal fields. Previously, we found that zinc oxide (ZnO) NPs that are neurotoxic to human dopaminergic neuroblastoma SH-SY5Y cells are mediated by lipoxygenase (LOX), not cyclooxygenase-2 (COX-2). Here, we examined whether human bone marrow-derived mesenchymal stem cells (MSCs), which are different from neuroblastoma cells, might exhibit COX-2- and/or LOX-dependent cytotoxicity of ZnO NPs. Additionally, changes in annexin V expression, caspase-3/7 activity, and mitochondrial membrane potential (MMP) induced by ZnO NPs and ZnO were compared at 12 hr and 24 hr after exposure using flow cytometry. Cytotoxicity was measured based on lactate dehydrogenase activity and confirmed by trypan blue staining. Rescue studies were executed using zinc or iron chelators. ZnO NPs and ZnO showed similar dose-dependent and significant cytotoxic effects at concentrations ≥ 15 μg/mL, in accordance with annexin V expression, caspase-3/7 activity, and MMP results. Human MSCs exhibited both COX-2 and LOX-mediated cytotoxicity after exposure to ZnO NPs, which was different from human neuroblastoma cells. Zinc and iron chelators significantly attenuated ZnO NPs-induced toxicity. Conclusively, these results suggest that ZnO NPs exhibit both COX-2- and LOX-mediated apoptosis by the participation of mitochondrial dysfunction in human MSC cultures.

Section: Introductionmentioning

confidence: 99%

Zinc Oxide Nanoparticles Exhibit Both Cyclooxygenase- and Lipoxygenase-Mediated Apoptosis in Human Bone Marrow-Derived Mesenchymal Stem Cells

Lee

et al. 2019

ToxicolRes

“…In our study, our histopathological examination for skin indicated that TiO2 NPs, GST did not penetrate into the skin layer (epidermis including stratum corneum/lucidum/granulosum/spinosum/basale). http://eaht.org Kim et al reported that histopathological finding showed the retinopathy in the eyes from animal treated with ZnO for 90 days and the presence of NPs was identified using micro-CT analysis method [11]. Considering this study, further study like repeated toxicity is thought to be needed to confirm whether presence or treatment-related effect for GST is observed or not.…”

Section: Histologymentioning

confidence: 87%

“…Kim et al reported that histopathological finding showed the retinopathy in the eyes from animal treated with ZnO for 90 days and the presence of NPs was identified using micro-CT analysis method [ 11 ]. Considering this study, further study like repeated toxicity is thought to be needed to confirm whether presence or treatment-related effect for GST is observed or not.…”

Section: Histologymentioning

confidence: 99%

“…To evaluate the toxicological effects in local treatment, the image-based method could be used to identify of chemical; micro-computer tomography (micro-CT), magnetic resonance imaging (MRI), optical tomography, fluorescence molecular tomographic imaging [ 9 – 10 ]. Recently, Kim et al reported that they used micro-CT to investigate the detection of ZnO NPs in eyes of rats and confirmed association with local distribution in ocular lesions [ 11 ].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Evaluation of potential eye or skin irritation/corrosion in rabbit exposed to TiO2 photocatalyst (GST)

Environ Anal Health Toxicol

Park

Seol

et al. 2021

TiO2 NPs photocatalyst is widely used in a variety of applications and products in the environmental and energy fields, including self-cleaning surfaces, air and water purification systems, sterilization, hydrogen evolution, and photoelectrochemical conversion. The possible biological and safety effects of TiO2 dermal exposure and absorption have not been well studied and more investigations on the potential health hazards of the TiO2 are needed. This study aimed to investigate potential effect of local lesions (eye and skin irritation/corrosion) for new TiO2 material powder, GST produced through sludge recycling of the sewage treatment plant in according to the OECD test guideline (TG 404, 405) and imaging evaluation (micro-computed tomography analysis), histopathology examination. Also, P-25, commercial photocatalyst was used to compare with GST. For the eye or skin irritation/corrosion test, the test substances (GST, P-25) showed no irritation/corrosion for local lesions and the GHS category was identified as a “No hazard class”. The imaging analysis indicated that GST did not penetrate or distribute in the local lesions (eye, skin) and the treatment-related effect was not observed in histopathology. Therefore, the present study revealed that new TiO2 powder, GST was considered to be no potential effects (irritation/corrosion), penetration or distribution in the local lesions (eye, skin).

“…The histopathological examination was performed to identify the treatment-related effects for treatment group. Considering retinopathy finding (presence of nanomaterials) observed in previous research of ZnO (particle size: 20 nm, charge: negative) for 90-day in rats [15], we examined the eyes carefully including harderian gland and there were no TiO2-related effects as Figure 5. Also, skin exposed with TiO2, there were no treatment-related changes considered to be toxicological lesion occurred by test substance administration as Figure 6.…”

Section: Histopathological Examinationmentioning

confidence: 99%

Repeated-dose 28-day dermal toxicity study of TiO2 catalyst (GST) in Sprague-Dawley rats

Environ Anal Health Toxicol

Park

et al. 2022

TiO2 have been studied on inhalation and skin exposure due to the properties of the materials’ use (cosmetics, paints and other products) and the additional safety information on other intake routes for the potential risk assessment is limited. The aim of this study was to obtain dose-range for subchronic study (repeated 90-day dermal toxicity) new TiO2 powder, GST produced through sludge recycling of the sewage treatment plant through repeated-dose toxicity in Sprague-Dawley (SD) rats. Three test groups for the GST were administered at 500, 1000, 2000 mg/kg B.W/day in addition to a control group (distilled water for injection). 5 male and 5 female rats were included in each group, and we examined the clinical signs, body weights, food consumption, necropsy (organ weights, macroscopic findings), hematological / biochemical parameters and histopathological findings (eye, skin). As a result of observations, there were no treatment-related effects including clinical signs, mortality, necropsy findings etc. Therefore, the present results suggest that the TiO2-related effects were not observed for dermal during 28-day and dose selection for repeated 90-day study was considered to be 500, 1000 and 2000 mg/kg B.W/day under the present study conditions.