Association between neuropeptides and mucins in Crohn's disease mucous cells

Crohn’s disease (CD) and ulcerative colitis (UC) are both inflammatory bowel diseases (IBD). Unlike UC, which is
limited to the mucosa of the colon, CD inflammation is characterized by chronic mucosal ulcerations affecting the
entire gastrointestinal tract. Goblet cells (GCs) can be found in some lining epithelia, particularly in the respiratory
and digestive tracts. GCs represent the main source of mucin that are the significant components of the
mucus layer; hypertrophy of GCs and an increase in mucin production are observed in many enteric infections.
The cytoplasm of goblet cells may also contain neuropeptides, such as serotonin, that can be altered in inflammatory
bowel disease (IBD). The defense system of the gut is represented by the intestinal mucosal barrier,
its protective function is strictly connected to the regulation of the mucus layer and the coordination of the
neuro-immune response. Paraformaldehyde-fixed intestinal tissues, obtained from fifteen patients with Crohn’s
disease, were analyzed by immunostaining for MUC2, MUC4, 5-HT, and VAChT. This study aims to define the
link between neuropeptides and mucins in mucous cells and their involvement in the inflammation process. Our
results showed in mucous cells of Crohn’s disease (CD) patients a high expression of MUC4 and a decrease in the
expression of vesicular acetylcholine transporter (VAChT) demonstrating the presence of an inflammatory state.