Intestinal Barrier in Inflammatory Bowel Disease: Mechanisms and Treatment

Inflammatory bowel disease (IBD) is an idiopathic intestinal inflammatory condition affecting the ileum, colon, and rectum, including ulcerative colitis and Crohn’s disease. Clinical symptoms include abdominal pain, diarrhea, and even bloody stools. The intestinal barrier is the first line of defense between the intestinal tract and the external environment, and maintaining its stability is essential for intestinal health. On one hand, it enables the digestion and absorption of water and nutrients; on the other, it plays a crucial role in reducing the absorption of toxins and the invasion of pathogens. Damage to the intestinal barrier has become one of the most important factors in the onset and progression of IBD. However, there is currently no literature that systematically reviews the mechanisms of the intestinal barrier in the pathogenesis of IBD and the factors influencing it. In this paper, we aimed to systematically elaborate on the role of the intestinal barrier in IBD through the perspectives of oxidative stress, intestinal flora, and cellular autophagy. Our goal was to explore the mechanisms of the intestinal barrier in IBD more deeply and to provide new insights for the diagnosis and treatment of IBD. This article will summarize the composition of the intestinal barrier, the factors affecting it, and strategies to protect it.