Elastaasi

Elastaasi, or elastase, is a family of serine proteases that cleave elastin and other protein substrates. In humans, the most well-known elastases are pancreatic elastase, produced by pancreatic acinar cells and active in the digestive tract, and neutrophil elastase, released by neutrophils during immune responses. Elastases are part of the chymotrypsin-like serine protease subgroup and use a catalytic triad of histidine, aspartate, and serine to hydrolyze peptide bonds.

Elastases play roles in normal tissue remodeling and defense, but if their activity is not properly controlled they can cause tissue damage. Pancreatic elastase contributes to digestion of dietary proteins in the small intestine, while neutrophil elastase helps dismantle pathogens and extracellular matrices during inflammation. Excess elastase activity has been implicated in inflammatory lung diseases such as chronic obstructive pulmonary disease and cystic fibrosis, particularly when counteracting inhibitors are insufficient.

Regulation is achieved by protease inhibitors, notably alpha-1 antitrypsin and secretory leukocyte protease inhibitor. Deficiency or imbalance of inhibitors can lead to excessive elastase activity and tissue damage, especially in the lungs.

Diagnostic use: fecal elastase-1 testing is used to assess pancreatic exocrine insufficiency; measurement of elastase activity in sputum or tissue can aid assessment of inflammatory or infectious lung conditions. Therapeutically, inhibitors of elastase are explored for disease-modifying approaches, and genetic or acquired deficiencies in protease inhibitors are important clinical considerations.