Pancreatic Elastase: Function & Diseases

Pancreatic elastase is a digestive enzyme produced by the pancreas. A deficiency of pancreatic elastase leads to digestive disorders.

What is pancreatic elastase?

Pancreatic elastase is also known as elastase-1. It is produced in the pancreas and functions as a digestive enzyme. The main function of the enzyme is to cleave elastin. Elastin is a fibrous protein. The enzyme is thus responsible for the cleavage of proteins and, together with enzymes such as trypsin or chymotrypsin, therefore belongs to the endopeptidases. Generally speaking, however, pancreatic elastase also belongs to the elastases.

Function, action, and tasks

Pancreatic elastase is an endopeptidase and is thus part of the peptidases. Endopeptidases cleave peptide bonds within a protein compound. In doing so, they usually proceed in a very specific manner. Elastase, for example, concentrates its activity mainly on elastin. Protein digestion begins in the stomach. There, the digestive enzyme pepsin, with the help of gastric acid, breaks down the proteins into medium-length and short peptide chains. In the small intestine, the digested food pulp then meets the digestive enzymes of the pancreas. These enter the small intestine via the pancreatic duct together with the alkaline pancreatic secretion. The pancreatic secretion is very important because it neutralizes the acidic food pulp from the stomach. Digestive enzymes work most effectively at a fairly high pH. Then in the small intestine, enzymes such as pancreatic elastase break down the peptidases into amino acids. These amino acids can then be absorbed through the intestinal mucosa and delivered to the bloodstream. From there, the protein building blocks enter the liver for further processing.

Formation, occurrence, properties and optimal values

Pancreatic elastase is formed in the exocrine part of the pancreas. However, the pancreas does not produce the enzyme directly in its active form, but first forms a precursor. This inactive precursor is also called a zymogen or a proenzyme. Most of the pancreatic digestive enzymes exist in an inactive form. They are not activated until they reach the small intestine. The first of these is trypsinogen. It is converted into its active form trypsin by enterokinase. Trypsin has the ability to activate other proenzymes. Pancreatic elastase is also activated by trypsin. If the pancreas were already producing working enzymes, these would also begin their work within the pancreas. As a result, the organ would digest itself. This is referred to as autodigestion. The proenzymes thus serve to protect the pancreas. Pancreatic elastase is excreted unchanged in the stool. Therefore, the level of pancreatic elastase in the stool can provide information about the activity of the pancreas. The reference value in stool is 200-500 μg E1/g in adults. 100-200 μg E1/g is considered indicative of mild to moderate pancreatic insufficiency. Levels < 100 μg E1/g stool may be considered severe pancreatic insufficiency. Elevated values in stool have no pathologic significance. In the blood, elastase is normally present only in small amounts. A normal value of < 3.5 ng/ml applies here. Decreased values have no significance here. An increase in elastase levels in the blood occurs in acute inflammation of the pancreas.

Diseases and disorders

Inflammation of the pancreas is also known as pancreatitis. The cause of the acute form is usually gallstones. These move from the gallbladder through the bile duct into the small intestine. They usually get stuck right at the mouth of the bile duct into the small intestine. However, not only does the bile duct open into the small intestine at this point, but so does the pancreatic duct. Thus, the pancreatic duct is obstructed by the gallstone(s). Unaffected by this, the pancreas continues to produce digestive enzymes and pancreatic secretions. Backflow from the large pancreatic duct into the small pancreatic ducts occurs. Due to unexplained mechanisms, the digestive enzymes activate themselves during this stasis and begin their digestive work. The digested walls of the pancreas then become inflamed. Other causes of pancreatitis are excessive alcohol consumption or infections with viruses. Pancreatitis begins with sudden severe pain in the upper abdomen that radiates in a belt-like pattern toward the back.Nausea and vomiting may also occur. Due to air accumulation in the abdomen and a defensive tension of the abdominal wall, the typical phenomenon of the rubber belly occurs. There is a risk of the secretion breaking through the walls of the pancreas. If the secretion leaks into the abdominal cavity, other organs may also be affected. The lethality of acute pancreatitis ranges from 5 to 99%, depending on the severity. If a deficiency of pancreatic elastase is detected in a stool examination, this suggests pancreatic insufficiency. In this disease, the pancreas is no longer able to produce sufficient digestive enzymes. The most common cause of insufficiency in adults is inflammation. In children, the main cause is the hereditary disease cystic fibrosis. Due to the lack of enzymes, digestion is disturbed. Affected individuals lose weight or fail to gain weight despite increased food intake. In children, failure to thrive can be observed. The stool is light-colored and extremely malodorous. If fat digestion is disturbed, fatty stools (steatorrhea) may occur. Here, the stool is very voluminous and shiny greasy. Diarrhea may also occur. If vitamin absorption in the intestine is restricted, an increased tendency to bleeding may be seen due to vitamin K deficiency. Determination of pancreatic elastase in stool is the fastest and least expensive way to detect pancreatic insufficiency.