Effect of an Obesogenic Diet on Mouse Corneal Wound Healing

Abstract

Purpose : Diet-induced obesity is a risk factor for metabolic syndrome and type II diabetes. Using a diet-induced obesity mouse model, we found that a short period (10 days) of obesogenic diet (OD) feeding impairs corneal epithelial wound healing. The purpose of this study was to evaluate the effects of extended OD feeding on corneal epithelial wound healing and the potential of diet reversal (DR) to ameliorate those effects.

Methods : Three groups of 6 week old C57BL/6 male mice were fed an OD or normal diet (ND) for 10 and 15 weeks or 10 weeks OD followed by 5 weeks ND (DR group). At the end of the feeding period, the mice received a 2mm diameter corneal epithelial wound. Mice were euthanized at 18 and 24 hours after wounding, eyes collected, corneas dissected, stained with DAPI and flat mounted to image with a DeltaVision Light microscope. Images were evaluated with ImageJ software. Three parameters important to wound healing were assessed: 1) open wound area 2) number of dividing epithelial cells and 3) basal epithelial cell density. Data were analyzed with one-way and two-way ANOVA and Tukey test was used for post-hoc comparisons. Significance was set at p<0.05.

Results : After 10 weeks feeding, there was no difference in open wound area between the ND and OD groups at 18h and 24h post-wounding. However, number of dividing epithelial cells (p=0.0166) and basal epithelial cell density (p=0.0012) were decreased in the OD group at 24h. After 15 weeks feeding, the OD group showed a larger open wound area at 18h when compared to the ND (p<0.0001) and DR (p=0.0049) groups; ND and DR groups were not different from each other. At 24h, the open wound area was similar between the three groups. At 24h post wounding, compared to the ND group, the OD group showed a reduction in the number of dividing epithelial cells (p=0.0235) and a reduction in basal epithelial cell density (p=0.0104). These reductions were not evident in the DR group.

Conclusions : OD feeding impairs corneal epithelial wound healing as evidenced by greater open wound area, decreased number of dividing epithelial cells and decreased basal epithelial cell density. DR appears to abrogate the negative effects of the OD, restoring the cornea’s ability to heal efficiently.

This is a 2020 ARVO Annual Meeting abstract.