The collective term chronic inflammatory bowel disease (IBD) embraces several clinical conditions characterized by intermittent or continuous inflammatory changes in the intestines. The most important chronic inflammatory bowel diseases are Crohn's disease and ulcerative colitis. Around 300,000 people in Germany currently suffer from these two diseases, which are associated with years of abdominal pain and diarrhoea, but also with severe fatigue. After prolonged disease progression, numerous extraintestinal manifestations (e.g. joint inflammations) can occur. The diseases usually occur at the age of 20 to 30 years, but infants and adolescents can also be affected. The exact causes of these diseases are still unknown. It is assumed that there is a genetic susceptibility, with environmental factors eventually triggering the onset of disease.
Both diseases usually require permanent treatment
In both diseases, medication and surgical measures can alleviate symptoms and help avoid complications at least partly. Crohn's disease so far cannot be cured; ulcerative colitis may be cured by surgical removal of the entire colon including the rectum. Surgical measures, however, are often associated with complications and reduced quality of life.
The aim of therapy for both diseases is to reduce the inflammation with anti-inflammatory drugs. Given that these diseases are chronic conditions, drug therapy is usually permanent. In addition, the therapies are systemic treatments. Until now, there is no therapeutic approach that sustainably improves the dysregulation of the intestinal immune system.
The aryl hydrocarbon receptor is a promising target in chronic inflammatory diseases
The intestinal flora (microbiome), which is strongly influenced by diet but also by administration of antibiotics, plays an important role in the development of chronic inflammatory bowel diseases. This is why nutrition and alternatives to antibiotic therapy play an increasingly important role in new treatment concepts for these diseases.
Recent studies have shown that the aryl hydrocarbon receptor (AhR) is a novel and promising therapeutic target in chronic inflammatory diseases. Meanwhile, numerous studies have shown that AhR plays an important role both in the innate and the adaptive immune systems in maintaining immune homeostasis and in regulating inflammatory reactions.