lipasen

Lipases are enzymes that catalyze the hydrolysis of triglycerides into free fatty acids and glycerol. They belong to the family of hydrolases and are found in many organisms and tissues. In humans, digestive lipases are essential for fat digestion and nutrient absorption.

The major digestive lipase is pancreatic lipase, produced by the pancreas and released into the small intestine. It acts on dietary triglycerides in the presence of bile salts, which emulsify fats and increase surface area. The pancreatic enzyme requires colipase to function effectively in the intestinal milieu and has an optimal activity around neutral to mildly alkaline pH. Other lipases contributing to fat digestion include gastric lipase, which operates in the stomach, particularly in infants.

Beyond digestion, several tissue-specific lipases regulate lipid metabolism. Lipoprotein lipase (LPL) sits on the vascular endothelium and hydrolyzes triglycerides in circulating chylomicrons and VLDL to release fatty acids for tissue uptake. Hepatic lipase and endothelial lipase act on various lipoproteins. Within adipose tissue, hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL) mobilize stored triglycerides during lipolysis, releasing fatty acids and glycerol for energy.

Clinical relevance includes the measurement of serum lipase as a diagnostic marker for acute pancreatitis, where lipase levels rise and remain elevated longer than amylase. Lipase supplementation is used in the treatment of exocrine pancreatic insufficiency. Genetic deficiencies of lipases can lead to metabolic disturbances such as hypertriglyceridemia due to impaired triglyceride hydrolysis.