Dynamic Monitoring of Cross-Bred Dogs for Translational Research in Ulcerative Colitis

Abstract Background: Ulcerative colitis (UC)is a complex, chronic, immu ne-mediated inflammatory disease. The preclinical studies and assessment of UC drugs remain a major challenge. Dogs share similar environmental, genomic, anatomical, and intestinal physiologic features with humans. However, the model of UC in dogs is not understood and lacks systematic assessment. Methods: We developed a model for UC in the cross-bred dogs by different dose of acetic acid retention enema. Simultaneously, physiological pathologic indicators, including blood routine examination, inflammatory factor and colonoscopy, were monitored continuously for 14 days. Furthermore, olsalazine was used to treatment UC to evaluate the feasibility of the model. Results: The percentage of lymphocytes increases after induction UC by 10% acetic acid; C-reactive protein (CRP) and Cyclooxygenase-2(COX-2) are mainly inflammatory markers after induction UC by 10% or 7.5% acetic acid; acetic acid aggravates mucosal damage in a dose-dependent manner, and OLZ prevents 10% acetic acid-induced UC. The acetic acid concentration is controlled between 7.5 % and 10%, and the continuous damage of this model is 10 days.Conclusions: We suggest that cross-bred dogs represent a useful clinical model of UC, and it is suitable for translational research. Finally, we provide a model and dynamic endoscope atlas for UC in dogs.