Zonalin (Serum) | Laboratory research

General Information

What is zonulin?
Zonulin is a protein synthesized in the small intestine, which participates in the absorption of water and nutrients by the cells of the intestinal wall, in the restoration and renewal of damaged cells. In addition to the small intestine, zonulin is secreted in the liver, kidneys, heart, brain, and immune cells. It is the only protein in the blood that reflects the permeability of the intestinal wall, and an increase in its concentration in the blood is considered a marker of intestinal barrier disruption. This causes an increase in the permeability of large molecules in the intestinal wall and the development of an inflammatory process in the intestinal wall. Elevated zonulin concentrations are associated with conditions such as celiac disease, type XNUMX diabetes, inflammatory bowel disease, and more.
Zonulin belongs to the so-called "tight junction" proteins that keep the cells of the intestinal wall tightly aligned and thus create a barrier that prevents a number of molecules from passing through the intestinal cell membrane. The intestinal barrier function protects us from toxic and various harmful substances entering the bloodstream.
During the increased permeability of the intestinal wall, unwanted molecules enter the blood stream and provoke chronic inflammatory and sometimes autoimmune diseases (celiac disease, Crohn's disease, ulcerative colitis).
Zonulin is found in almost all food products, but is most abundant in wheat and other cereals, dairy products, and legumes. It is not present in meat and fish products.

Symptoms
Symptoms in conditions characterized by increased zonulin levels depend on the disease.
Celiac disease is often accompanied by abdominal pain, bloating, diarrhea, weight loss, and general weakness.
Type I diabetes mellitus is characterized by increased thirst, polyuria, weight loss, general weakness.
In inflammatory bowel diseases (Crohn's disease), the symptoms are similar - abdominal pain, diarrhea, weakness, weight loss.
Zonulin studies are sometimes performed in the diagnostics of metastatic tumors (eg, pancreatic cancer, breast cancer), because it is believed that zonulin increases the permeability of intestinal tissue to large molecules, promoting the spread of metastases.