A hereditary rat model of umbilical hernia: characterization, susceptibility locus mapping, and mechanism exploration

Limited progress in understanding umbilical hernia (UH) pathogenesis stems from scarce genetically stable models. We established a hereditary rat model recapitulating human and livestock UH across phenotypic, histological, and molecular dimensions. Persistent herniation from infancy to adulthood exhibited size-weight correlation in adults (r² = 0.139, p < 0.01). Histopathology revealed hernial ring fibrosis, linea alba defects, and collagen dysregulation: reduced collagen I (22.5% decrease, p < 0.01) and elevated collagen III (23.0% increase, p < 0.001), confirming ECM imbalance. Microsatellite analysis validated genetic stability (mean heterozygosity = 0.214; PIC = 0.171). Transcriptomics identified 1,031 differentially expressed genes (712↑, 319↓), enriched in ECM remodeling and immune homeostasis. Cross-species comparative analysis of transcriptomic datasets from established porcine models uncovered conserved pathological mechanisms. Validation of key hub genes (CCL2, EGFR, and ITGA3) by qPCR and ELISA implicates potential pathways in collagen disorganization. This homogeneous model bridges translational gaps for etiology and therapy studies.