BACKGROUND: Chronic Inflammatory Enteropathy (CIE) in dogs refers to a disorder characterized by chronic intestinal inflammation. It can lead to symptoms such as persistent diarrhea, vomiting, weight loss, and anorexia. This disease is typically caused by various factors, including food allergies, infections, and immune disorders. Accurate diagnosis and appropriate treatment are essential for improving the quality of life and health of affected dogs.
OBJECTIVES: This research investigates the molecular mechanisms and gene expression patterns in CIE using bioinformatics methods and molecular experiments.
METHODS: single-cell RNA sequencing (scRNA-seq) data from samples of healthy dogs and those with chronic inflammatory enteropathy (CIE) were processed and normalized using the Seurat package version 3. After identifying 20 distinct cell clusters, the expression of key genes associated with major signaling pathways was evaluated using RT-qPCR in 35 samples (25 diseased samples and 10 control samples).
RESULTS: Comparing gene expression between CIE samples (4 samples) and healthy samples (3 samples) yielded 385 differentially expressed genes (DEGs). KEGG pathway analysis revealed a key signaling pathway associated with Human T-cell Leukemia Virus type 1 (HTLV-1) infection, involving 217 genes. Among these, 15 genes were of particular importance in this study. These findings, confirmed by bioinformatic methods, provide deeper insight into the genetic regulation in CIE and suggest mechanisms affecting cellular function. RT-qPCR results showed that EGR2 was upregulated in diseased samples, while CSF2 and ETS2 were downregulated. NFKBIA also showed a significant decrease. Conversely, the overexpression of SLC2A1 and NFATC4 indicated their roles in glucose metabolism and immune regulation.
CONCLUSIONS: The present study revealed that dysregulation of signaling pathways associated with viral infection and immune response, including the cfa05166 and JAK-STAT pathways, plays a pivotal role in the pathogenesis of the disease, which could pave the way for the development of diagnostic biomarkers and novel therapeutic approaches for this enteropathy.