Lipase is an enzyme found in lysosomes that digests lipids. Lipase converts lipids such as glycerides to glycerol and free fatty acids.
Increased serum levels of lipase occur during acute pancreatiti. Measuring serum lipase levels is considered more specific for pancreatitis than serum amylase levels.
In recent years our knowledge of lipases has increased dramatically, especially in the areas of molecular structure and mechanism of action. The term lipase usually refers to triacylglyceride lipases, rather than the related phospholipases.
Lipases have been quoted as one of the most versatile of enzymes by most research scientists of the world.
Most of the body's lipase is manufactured in the pancreas, although some of it is secreted in the saliva, as well. Pancreatin contains lipase along with two other groups of enzymes: proteases and amylase.
The bulk of dietary lipids are a class called triacylglycerols and are attacked by lipases to yield simple fatty acids and glycerol, molecules which can permeate the membranes of the stomach and small intestine for use by the body. Gastric lipase, secreted by the stomach lining, has a pH value for optimal activity around neutrality and would appear, therefore, to be essentially inactive in the strongly acid environment of the stomach.
It is suggested that this enzyme is more important for infant digestion since the gastric pH in infancy is much less acid than later in life. Most lipid digestion in the adult occurs in the upper loop of the small intestine and is accomplished by a lipase secreted by the pancreas.
Lipase breaks down neutral fats (triglycerides) into glycerol (an alcohol) and fatty acids. Before lipase can digest fat, bile, an emulsifier, must break the fat down into smaller units. People who are low in HCl cannot make adequate bile.
HCl deficiency is caused by protease deficiency (required to provide adequate acidity) and lipase deficiency (required to carry chlorides). Thus lipase deficiency, inadequate HCl, and stagnation of bile are interrelated.
Deficiency of Lipase
There are two types of lipase-deficient people. The first are those who are truly fat intolerant, get sick when they eat fat, and have gallbladder problems. These people substitute sugar for fat. The second are people who are complex-carbohydrate intolerant and make up for it by eating excessive amounts of fat. These people gradually develop a lipase deficiency.
Lipase is important in maintaining optimum cell permeability, which allows nutrients to flow easily into the cells and wastes to flow out. Two conditions arising from lipase deficiency are diabetes and glucosuria (sugar in the urine without symptoms of diabetes).
Most people associate diabetes with sugar intolerance, but fat intolerance is the major enzyme culprit. The inability to digest fat interferes with insulin metabolism and the transport of glucose into the cell by insulin.
People with pancreatic insufficiency and cystic fibrosis frequently require supplemental lipase and other enzymes. In addition, those with celiac disease1 or Crohn’s disease2 and perhaps some people suffering from indigestion3 may be deficient in pancreatic enzymes including lipase.
Protease
Amylase
Lipase
Lactase
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