Journal
NANOIMPACT
Volume 17, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.impact.2019.100198
Keywords
Metal oxide engineered nanomaterials; Nanometals; Corneal epithelium; Corneal wound healing; Nanotoxicity
Funding
- National Institute of Environmental Health Sciences of the National Institutes of Health as part of the Nanotechnology Health Implications Research (NHIR) Consortium [NIEHS U01 ES027288]
- NIH [U24ES026946, S10 OD021789]
- NIH National Eye Institute [P30 EY12576]
Ask authors/readers for more resources
Ocular exposure to metal oxide engineered nanomaterials (ENMs) is common as exemplified by zinc(II) oxide (ZnO), a major constituent of sunscreens and cosmetics. The ocular surface that includes the transparent cornea and its protective tear film are common sites of exposure for metal ENMs. Despite the frequency of exposure of the ocular surface, there is a knowledge gap regarding the effects of metal oxide ENMs on the cornea in health and disease. Therefore, we studied the effects of metal oxide ENMs on the cornea in the presence or absence of injury. Cell viability of immortalized human corneal epithelial (hTCEpi) cells was assessed following treatment with 11 metal oxide ENMs with a concentration ranging from 0.5 to 250 mu g/ml for 24 h. An epithelial wound healing assay with a monolayer of hTCEpi cells was then performed using 11 metal oxide ENMs at select concentrations based on data from the viability assays. Subsequently, based on the in vitro results, in vivo testing of precorneal tear film (PTF) quantity and stability as well as a corneal epithelial wound healing were tested in the presence or absence ZnO or vanadium(V) oxide (V2O5) at a concentration of 50 mu g/ml. We found that WO3, ZnO, V2O5 and CuO ENMs significantly reduced hTCEpi cell viability in comparison to vehicle control or the other metal oxide ENMs tested. Furthermore, ZnO and V2O5 ENMs also significantly decreased hTCEpi cell migration. Although ZnO and V2O5 did not alter PTF parameters of rabbits in vivo, corneal epithelial wound healing was significantly delayed by topical ZnO while V2O5 did not alter wound healing. Finally, hyperspectral images confirmed penetration of ZnO and V2O5 through all corneal layers and into the iris stroma. Considering the marked epithelial toxicity and corneal penetration of ZnO, further investigations on the impact of this ENM on the eye are warranted.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available