Purchase this article with an account.
Maika Kobayashi, Tsutomu Igarashi, Chiaki Fujimoto, Hisaharu Suzuki, Hiroshi Takahashi; Short-time exposure of hyperosmolarity induces interleukin 6 in corneal epithelial cells. Invest. Ophthalmol. Vis. Sci. 2014;55(13):1969.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Tear hyperosmolarity is assumed to play a major role in causing dry eye disease. Recently accumulated data have shown that hyperosmolarity induces production of inflammatory cytokines and chemokines, and up-regulates cell surface markers on the corneal cells and immune cells.We examined the effect of short-time exposure of hyperosmolarity in producing inflammatory cytokines in corneal epithelial cells in vitro.
Human corneal epithelial cells (HCE) were cultured in different osmotic conditions; 310 (control), 400, 500, 600, 700, 800, 900, and 1000mOsm. To examine the cytotoxicity to HCE by hyperosmotic stress of a short time (10 minutes) or 24 hours exposure, the release of lactate dehydrogenase (LDH) was evaluated. Then, production of inflammatory cytokines including IL-6, IL-1b, IL-8, IL-23 and TGF-β by hyperosmotic stress of a short time exposure was measured by enzyme-linked immunosorbent assay (ELISA) and semi-quantitative real time PCR.
After 24-hour culture, cells were all dead with over 700 mOsm osmolarity, and were damaged with 500 and 600 mOsm, while with 400 mOsm cells did not show morphological change. However, the release of LDH after 24-hour culture increased significantly even in 400 mOsm medium compared to control (p<0.01). On the other hand, short-time exposure with any osmolarity did not cause increase in LDH. In the ELISA experiment, cytokines such as IL-1b, IL-8, IL-23, and TGF-β was not detected in the short-time exposure with any osmolarity, while IL-6 production increased depending on the osmolarity; the peak was 32 pg/ml in 700 mOsm which was significantly higher than control (4.77pg/ml, p<0.01). Similarly, IL-6 mRNA expression was found increased depending on the osmolarity; the peak was in 700 mOsm which was 1.73 times higher than control (p<0.05).
The short time exposure of hyperosmolarity does not show cytotoxicity in the corneal epithelial cells, while it can trigger inflammation on the ocular surface.
This PDF is available to Subscribers Only