RESUMEN
Inflammatory bowel disease (IBD), comprising Crohn’s disease and ulcerative colitis, is a lifelong disease that manifests with chronic intestinal inflammation, sequential fibrosis, and an increased risk of colitis-associated colon cancer (CAC). The combined effects of genetic, immunological, environmental, and microbial factors render it difficult to determine the specific mechanism underlying the induction and perpetuation of IBD. Various animal models of IBD have contributed enormously to the understanding of IBD pathogenesis in terms of genomics, transcriptomics, proteomics, microbiome, and drug development of novel therapeutics. Although comprehensive research on IBD has been enabled by advanced technologies, such as genetically engineered models, there is a great need to develop relevant in vivo models of colitis and fibrosis. Here, we review 4 categories of animal models of acute and chronic intestinal inflammation, fibrosis, and CAC: chemically induced, genetically engineered, T cell transfer, and spontaneous gene mutation models.
RESUMEN
Background/Aims@#Crohn’s disease is associated with altered body composition, such as low muscle mass, which can affect clinical outcomes. However, there are few studies regarding the effect of sarcopenia on prognosis of Crohn’s disease. In this study, we evaluated the body composition at the initial diagnosis of Crohn’s disease and analyzed the clinical meaning of sarcopenia. @*Methods@#We conducted a retrospective review of medical records of patients who were diagnosed as Crohn’s disease and underwent computed tomography within 3 months after diagnosis. Sarcopenia was defined as an L3 skeletal muscle index (SMI) of < 49 cm2/m2 for men and < 31 cm2/m2 for women. Outcomes such as need for hospitalization, surgery, use of steroids, immunomodulators and biologics were analyzed. @*Results@#A total of 79 patients (male, 73.4%; mean age, 29.9 years) were included and 40 patients (51%) were diagnosed as sarcopenia. C-reactive protein (CRP) level was correlated with sarcopenia (P= 0.044). Erythrocyte sedimentation rate (ESR) showed a tendency to decrease inversely with SMI (r = –0.320, P= 0.008) and hemoglobin and albumin tended to increase in proportion to SMI (hemoglobin: r = 0.271, P= 0.016 and albumin: r = 0.350, P= 0.002). However, there was no statistically significance in time-to-first-event analysis in aspects of sarcopenia. @*Conclusions@#Approximately 50% of patients with newly diagnosed as Crohn’s disease had sarcopenia. CRP levels were higher in the sarcopenia group and SMI correlated with ESR, hemoglobin, and albumin. However, none of prognostic values were demonstrated.