Lipaza

Lipaza, known as lipase in English, is a family of serine hydrolase enzymes that catalyze the hydrolysis of triglycerides into free fatty acids and glycerol. Lipases play essential roles in digestion and lipid metabolism in many organisms, including humans. They act at lipid–water interfaces and are distributed in digestive tissues, blood, adipose tissue, and the vascular endothelium.

In humans the principal digestive enzyme is pancreatic lipase, secreted by the exocrine pancreas into the small intestine, where it digests dietary triglycerides. Gastric lipase, produced in the stomach, contributes to fat digestion at acidic pH, particularly for milk fats in infants. Additional lipases include hepatic lipase, lipoprotein lipase, and hormone-sensitive lipase, which regulate triglyceride turnover in circulation and adipose tissue.

Pancreatic lipase requires colipase as a cofactor to function in the presence of bile salts and bile-salt micelles. It operates via a catalytic triad, typically Ser-His-Asp, and shows interfacial activation, adopting an open “lid” conformation when in contact with lipid droplets. Many lipases prefer neutral to slightly basic pH and require calcium ions for stability.

Clinical relevance: Elevated serum lipase is a diagnostic marker for acute pancreatitis, often alongside amylase; lipase elevations rise earlier and remain elevated longer. Pancreatic exocrine insufficiency can cause steatorrhea and fat-soluble vitamin deficiencies, assessed in part by fecal elastase tests. Pharmacological lipase inhibitors, such as orlistat, reduce dietary fat absorption by inhibiting intestinal lipases.

Industrial and research uses: Lipases are widely used in food processing, biodiesel production, and biocatalysis due to their specificity for triglycerides and ability to function under mild conditions. They are also studied for therapeutic and diagnostic roles in metabolic diseases.