Abstract
Purpose :
Dry eye syndrome(DES) is a very common multifactorial disease of the ocular surface epithelium affecting a wide age group of individuals. Hence we aimed to establish and compare 3 dry eye models using the pharmacologic inhibition of aqueous tear production, application of environmental stress and the effect of sclerosing agents on the lacrimal gland cells, so as to identify an appropriate one for lacrimal tissue regeneration
Methods :
After obtaining Institutional Animal Ethics Committee Approval, female C57BL/6N mice were randomized into three groups: a control (Group A) and 3 induced groups. Pharmacologically dry eye was induced in one eye by an Intramuscular injection of (5mg/24h) scopolamine (Group B) for 5 days. In the second dry eye model, mice were placed in a laminar airflow cabinet with an airflow rate of 0.5m/s (Group C) for 7 days. The 3rd dry eye animal model was created by injecting ethanolamine oleate sclerosing agent(Group D) into the gland without spillage into the surrounding tissue to cause destruction of the lacrimal gland. Post-injection inflammation was treated by injecting diclofenac intraperitoneally. The dry eye status was measured using endodontic points, corneal defects (by slit-lamp) and histopathological evaluation.
Results :
All the test groups showed evidence of dry eye disease with evidence of decreased lacrimation, corneal epithelial defects and varying degree of inflammation. Induction of dry eye was 3 days in Group D, 7-14 days in Group B and C. Group D also showed increased Inflammation, increased corneal epithelial defects, reduced size of the lacrimal gland and reduced goblet cells, reduced acinar density, but minimal conjunctival inflammation as compared to Group A, B and C. These changes became more pronounced on day 7 after induction.
Conclusions :
This study demonstrates successful induction of dry eye models using different interventions. Of all the applications, the sclerosing agent appeared to produce more severe dry eye whereas the changes were mild to moderate with environmental changes and moderate with scopolamine. Hence these models can be generated based on the nature of the experiment and the desired severity of the disease.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.