Hans D Westermeyer*, Jacklyn H Salmon and Michala de Linde Henriksen

North Carolina State University, College of Veterinary Medicine, Department of Clinical Sciences, Raleigh, NC

*Corresponding Author: Hans D Westermeyer, North Carolina State University, College of Veterinary Medicine, Department of Clinical Sciences, Raleigh, NC.

Received: September 08, 2025; Published: October 06, 2025

Abstract

Purpose: The purpose of this pilot study was to explore the possibility of a common molecular pathway leading to the development of primary angle closure glaucoma (PACG) in dogs. This was done by comparing the aqueous humor (AH) microRNA (miRNA) profile of dogs predisposed to developing PACG to that of normal healthy dogs.

Material and Methods: The AH (250l) samples were collected under general anesthesia from the normal eye of dogs that had been diagnosed with PACG associated intraocular pressure (IOP) elevation in the opposite eye (study group; n=3 eyes). Aqueous humor from normal healthy eyes was also collected from purpose bred, beagle dogs immediately after euthanasia (control group; n=3 eyes). The AH samples were submitted to a commercial laboratory for miRNA sequencing and analysis.

Results: MicroRNA was successfully sequenced from all six AH samples. There were 19 sequences (16 novel and 3 known) which showed differential expression (13 upregulated and 6 downregulated) between eyes of the study group and the control group (P < 0.05). There were three sequences that were expressed in all study group dogs but not in any of the control group dogs (cfa-miRNA-206, NovelmiRNA-222, and NovelmiRNA-366).

Conclusions: There may be differences in miRNA expression in dog eyes predisposed to developing PACG prior to the onset of IOP elevation. Further investigation of these differences may lead to the discovery of the molecular mechanisms involved in IOP elevations in dogs with PACG and the development of novel diagnostic and treatment modalities.

Keywords: MicroRNA Expression; Aqueous Humor; Predisposed; Glaucoma

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Citation

Citation: Hans D Westermeyer., et al. “Differences in MicroRNA Expression in Aqueous Humor of Dogs Predisposed to Developing Primary Angle Closure Glaucoma: A Pilot StudyActa Scientific Veterinary Sciences 7.9 (2025): 03-08.

Copyright

Copyright: © 2025 Hans D Westermeyer., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.