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2018 Agenda and Abstracts | < Previous Next >
2018
OMIG Abstract Purpose: To evaluate the preventive cytoprotective effect of alpha-melanocyte-stimulating hormone (a-MSH), a neuropeptide present in human aqueous humor, on corneal endothelium (CE) survival in the presence of acute oxidative stress in eye bank-stored human corneas using specular microscopy image quality assessment. Methods: A pilot in vitro study was conducted using paired research grade human donor corneas (courtesy of Eversight Eye Bank). Randomly selected corneas from each pair were pretreated with either 10-4M or no a-MSH in Optisol-GS (15 minutes, at 37°C) and then subjected to 1.4 mM H2O2 in PBS (15 minutes, at 37°C) treatment. Corneas were then transferred to Optisol-GS medium and stored at 4°C. Images were taken at baseline and repeated twice per week using CellChekD+ specular microscope. The endothelial morphometric parameters [cell density (ECD), coefficient of variation (CV) and % hexagonality (HEX)] and corneal pachymetry were recorded. Results: The baseline morphometric parameters and pachymetry were comparable between both groups (paired t-test, all p > 0.05). CE cell loss over the first two weeks was lower (n=4; day 5: 8.2±4.6%, day 7: 16.7±11.5%, day 14: 53.2±27.1%) in the a-MSH group compared to the control group (n=4; day 5: 15.6±8.4%, day 7: 38.9±23.9%, day 14: 55.6±25.7%) although this was not statistically significant (p=0.0625; Wilcoxon Signed-Rank Test). The CV and %HEX at all measurement periods fluctuated in both groups, with an upward and a downward trend, respectively. Pachymetry increased in both groups over the 14 days, but to a significantly less degree in the a-MSH group (p=0.039; Paired t-test). Under fluorescence microscopy using a live–dead viability assay a higher % of Propidium Iodide+ (dead) cells were observed for the control untreated corneas (p=0.03, n=2, paired t-test). Conclusion: a-MSH pre-treatment of donor corneas attenuates CE loss and pachymetry changes during storage after acute oxidative stress induction. Supplementation of corneal storage medium with a-MSH may prolong hypothermic tissue storage time and lead to higher quality graft tissue. Disclosure: N (ZS, JY, AA, CJ); S (ZL; EBAA); C, S (RD=Shire) S (RD; Allergan, NEI, Eversight); C (RD; Dompe) Support: EBAA/Richard Lindstrom Research Grant (to ZL), Eversight (to RD).
2018 Agenda and Abstracts | < Previous Next >
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