The Study of the Effects of Glucose on Cultured Human Corneal Epithelial Cells

PURPOSE: In this study, we evaluated the effects of glucose on the proliferation, migration, morphological characteristics, and proteinase expressions in human corneal epithelial cells to discover the cause of diabetic corneal epithelial complications. METHODS: Human corneal epithelial cells transfected by SV40 were cultured in media containing 17.5 mM (control), 25 mM, and 100 mM D-glucose to stimulate a diabetic condition. In some experiments, 25 mM or 100mM D-mannitol was added to the media to control for the osmotic effect of glucose. We performed MTT analysis of the proliferation assay, cell count of the migration assay, scanning electron microscopic (SEM) examination for morphologic change, and RT-PCR for the expression of mRNA of metalloproteinase (MMP). RESULTS: Raising the concentration of glucose from 25 mM to 100 mM significantly decreased in the cellular proliferation and migration. These findings were not observed in the presence of 25 mM or 100 mM mannitol. In SEM, the pseudopods of the cells were markedly decreased in the 100mM glucose media. Although the expression of MMP-2 was not significantly different, that of MMP-9 was significantly increased with increasing glucose concentration. CONCLUSIONS: Higher levels of glucose show a significant effect on cellular proliferation, migration, morphology, and the expression of MMP-9 in corneal epithelial cells. This study may be an initial step in understanding the mechanism of corneal epithelial wound healing in diabetic patients.

The Role of Nuclear Factor Kappa B on Lens Epithelial Cells after Ultraviolet B Irradiation

PURPOSE: This study was performed to determine the role of nuclear factor kappa B (NF-kappa B) on the lens epithelial cell death after ultraviolet (UV) irradiation. METHODS: Simian virus 40 transfected human lens epithelial cells (HLE B-3 cells) were used in this study. UVB located at 10cm from the bottom was irradiated during 1, 2, 3 and 4 minutes. To measure the cytotoxicity MTT assay was used. Translocation of NF-kappa B was examined by immunocytochemistry with anti NF-kappa B p65 antibody and electrophoretic mobility shift assay (EMSA). To confirm the role of NF-kappa B, the cells were pretreated with sulfasalazine, a specific inhibitor of NF-kappa B, for 30 minutes before irradiation, and cytotoxicity and translocation of NF-kappa B were evaluated. RESULTS: UV irradiation produced a progressive cytotoxic effect in cultured HLE B-3 cells after 1 minute and maximum cytotoxicity was reached after 3 minutes irradiation. When HLE B-3 cells were irradiated with UVB, the translocation of NF-kappa B was observed in immunocytochemistry. These translocations were peaked 6 hours after UV irradiation in EMSA. In HLE B-3 cells pretreated with sulfasalazine, the translocation of NF-kappa B was blocked. The cellular death after UV irradiation was markedly blocked by sulfasalazine. UV irradiation can translocate NF-kappa B and sulfasalazine is a useful blocking agent in this pathway. In addition, sulfasalazine can prevent cellular death after UV irradiation. CONCLUSIONS: These findings suggest that NF-kappa B plays an important role in cellular death after UV irradiation.

The Clinical Results of Hydrophobic Single-Piece Acrylic Intraocular Lenses after Cataract Surgery

PURPOSE: To report the results of the clinical use of single-piece acrylic intraocular lenses (IOLs; AcrySof(R), SA60AT, Alcon) compared with three-piece acrylic IOLs (AcrySof(R), MA60BM, Alcon) after cataract surgery. METHODS: We retrospectively analyzed data of the extent of IOL decentration and tilting measured with Scheimpflug camera (EAS-1000 anterior eye segment analysis system, Nidek) at 1 week, 1 month and 2 months after surgery, the difference in the preoperative predictive refraction and the postoperative actual refraction, and the higher order RMS (root mean square) value with WASCA wavefront analyzer (Carl Zeiss Meditec, Germany) between the two groups (SA60AT group: N=30 , MA60BM group: N=30). RESULTS: The extent of IOL decentration was statistically insignificant in both groups (p>0.05), but the amount of IOL tilting in the SA60AT group was significantly less than that in the MA60BM group at 1 week, 1 month and 2 months postoperatively (p<0.05). There was no statistically significant difference in the preoperative predictive refraction and the postoperative actual refraction between the two groups. The triangular coma aberrations and the higher order (HO) RMS values were, however, significantly less in the SA60AT group (p<0.05). CONCLUSIONS: The SA60AT IOLs provided a better postoperative centration and a smaller HO RMS value than the MA60BM IOLs. Based on these results, we expect that SA60AT IOLs will provide a better clinical outcome in the aspect of quality of vision.