Selective Nanoparticulate Systems for Drug Delivery in Inflammatory Bowel Disease.

Inflammatory bowel disease is a result of inappropriate continuous non-specific inflammation in the intestinal tract, which in turn is aggravated by defects in the activation of the mucosal immune system and in the barrier function of the intestinal epithelium. The most prominent manifestations of IBD are ulcerative colitis (UC) and Crohn's disease (CD). UC is characterized by a continuous pattern that commonly starts with lesions in rectum mucosa and is contained in the colon. On the other hand, CD affects the ileum and colon in a discontinuous pattern, and the lesions are often transmural. Conventional therapies often face limitations such as systemic side effects, poor drug stability, and low site-specificity. In recent years, nanoparticle (NP) systems have emerged as a promising strategy to overcome these challenges, offering improved targeting, controlled release, and enhanced therapeutic efficacy. Several studies have shown that the preferential accumulation of NPs in the inflamed colon is influenced by the pathophysiological changes associated with IBD, including alterations in transit time, pH value, enzymatic activity, microbial composition, and mucus integrity. These disease-specific characteristics provide unique opportunities to design smart and responsive NPs that enhance drug delivery and therapeutic efficacy while minimizing systemic exposure. This work presents an overview of novel technologies based on nanosystems, with the ability to specifically target the affected areas of the GI tract in inflammatory bowel disease.