Analysis of the global gene expression and miRNA profile from dogs with immature and mature cataracts.

Abstract

In veterinary medicine, cataracts are the main cause of vision loss in dogs, affecting crosses or purebred animals. Human and animal lenses are relatively isolated tissues that contribute to light refraction to the retina and are surrounded by aqueous and vitreous humor. Lenses are transparent in young human and animal patients, but changes in their architecture and constitution occur as they age. These changes include the development of a hard and compact nucleus, focal opacity and, ultimately, the development of the cataract. These features allow lenses to be used as adaptive models to study the role of mRNA and miRNAs in cataracts that, until now, have not been studied in canine. Therefore, the aim of this study is to carry out a global gene expression analysis of cataract carrier dogs, as well as to verify the molecular evidence of the role of miRNAs in the regulation of this pathological condition. For that, 4-5mm fragments from anterior capsules obtained from the capsulorexe of phacoemulsification surgery will be harvested from ten animals with immature and ten animals with mature cataracts. Fragments of equal size will be collected from six healthy animals with transparent lenses, which will constitute the control group. Transcriptomic analysis will utilize the Canine Gene 1.1 ST Array strip (Affymetrix®) for microarray analysis. This assay allows for a global analysis of the transcriptome of the canine species. A portion of the genes identified as differentially expressed in the microarray will be validated by the real-time PCR technique. Analysis of the microtranscriptome (miRNAs) will be conducted using the PCR Profiler technology (Qiagen). (AU)