Comparative Circulating microRNA Profiling in Dogs with Pyometra and Other Inflammatory Diseases.

Area of Science:

• Veterinary Medicine
• Molecular Biology
• Biomarker Discovery

Background:

• Circulating microRNAs (miRNAs) are key regulators of inflammation and potential disease biomarkers.
• Limited data exists on circulating miRNA profiles in naturally occurring canine inflammatory diseases.
• Pyometra and other inflammatory conditions in dogs present a need for better diagnostic tools.

Purpose of the Study:

• To characterize circulating miRNA expression in dogs with pyometra, non-reproductive inflammatory diseases, and healthy controls.
• To identify shared and disease-specific miRNA alterations using small RNA sequencing.
• To discover potential minimally invasive biomarkers for canine inflammatory diseases.

Main Methods:

• Small RNA sequencing was performed on plasma samples from three groups of dogs: pyometra, non-reproductive inflammatory diseases, and healthy controls.
• Global expression patterns were analyzed using heatmap and principal component analysis (PCA).
• Differential expression analysis was conducted using DESeq2 with an adjusted p-value threshold of < 0.05.

Main Results:

• Global miRNA expression patterns clearly separated healthy dogs from diseased dogs.
• 39 circulating miRNAs were commonly altered in both pyometra and non-reproductive inflammatory diseases compared to controls.
• Pyometra showed 83 differentially expressed miRNAs, while non-reproductive inflammatory diseases had 4. Three specific miRNAs (cfa-miR-885, cfa-miR-599, cfa-miR-122) differed between the two disease groups.

Conclusions:

• Circulating miRNA profiles in dogs with pyometra reflect systemic inflammation and disease-specific molecular changes.
• Commonly altered miRNAs may serve as general biomarkers for canine inflammation.
• Specific miRNAs identified could be valuable for diagnosing and understanding pyometra and other inflammatory conditions in dogs.