A lipase test is prescribed for suspected gastrointestinal diseases. Let's take a closer look at the enzyme called lipase - what is it? What functions does it perform in the body, and what diseases is indicated by its deviation from the norm in test results?
Lipase is an enzyme produced by certain organs of the human body. It dissolves, separates and digests various fractions of fats, and also performs a number of other important tasks. Pancreatic lipase is of primary importance. Its activity can be assessed when fats enter the body.
The enzyme “works” together with colipase (coenzyme) and bile acids. In addition to the pancreas, it is produced by the lungs, stomach, intestines and even leukocytes - white blood cells belonging to the immune system. There is also such a thing as “lingual lipase”. What it is? This is an enzyme that is produced in the oral cavity of newborn children for the primary breakdown of food, that is, for the breakdown of mother's milk.
Pancreatic lipase
Its level in the blood is much higher than the level of other types of lipase. However, during pancreatectomy (removal of the pancreas), a small percentage of lipase will still remain due to its release by other organs. Lipase is normally absent in urine tests. After “birth” in the pancreas, it enters the intestines, where it performs its main function - it breaks down fats. Pancreatic lipase plays a particularly important role. It is for its determination that blood is donated, since changes in this indicator can help in the diagnosis of many diseases. We'll look at which ones below.
Pancreatic lipase - what is it? This is an enzyme produced by the pancreas that “breaks down” triglycerides into glycerol and higher fatty acids. Often it breaks down mushrooms that are already emulsified with bile.
What is lipase and what is it for?
The dry language of science positions pancreatic lipase as an enzyme from the subclass of esterases (in the class of hydrolases) and states the similarity of its properties with hepatic blood lipase.
Deciphering what has been said, it should be clarified that hydrolases include chemical compounds-biocatalysts (enzymes) that hydrolyze (break down) dietary fats () into free glycerol and substances from the class of higher fatty acids.
In other words, without the participation of this enzyme, which is part of pancreatic juice, neither the absorption of fats by the body, nor fat metabolism in it, and therefore life as such, would be impossible. Because fats, both mobile and in the form of reserves, are necessary for the body to achieve many goals - from creating compact, strong, selectively permeable cell membranes to protecting the body from fractures and bruises when it falls backwards (face up - back and butt down).
This complex compound is the active fraction of the enzyme. Lipase is capable of breaking down complex fatty substances into triglycerides, and then into fatty acids, which ultimately go towards energy metabolism.
In addition to energy production, lipase also takes part in the absorption of polyunsaturated fatty acids and fat-soluble vitamins A, D, E, F, K.
Enzyme secretion
Lipase is an enzyme that is secreted in many organs, but in different quantities.
hepatocyte lobules; stomach cells; intestinal enterocytes; lung tissue; white blood cells - leukocytes; baby's oral cavity during breastfeeding.
The main role of breaking down complex fats into simple substances is provided by pancreatic lipase. A certain sequence is required to activate it. It is pancreatic lipase that is the fraction of the enzyme that is determined by a blood test.
The enzyme enters the gastrointestinal tract in the form of an inactive prolipase fraction. After exposure to bile acids and colipase (another enzyme produced by the pancreas), prolipase turns into an active form and begins to perform its function. It begins to break down those fats that have already been chemically influenced and emulsified with bile acids.
In addition to the main action, there is a secondary role of that small amount of the enzyme, fractions of which are produced by other organs.
Lingual lipase, which is produced by special glands in newborns, ensures the beginning of the digestive process with the breakdown of fats in breast milk already in the oral cavity. This can be explained by the fact that pancreatic enzymatic activity is poorly developed in the first year of life and does not allow the complete absorption of substances necessary to ensure energy balance.
Hepatic lipase is responsible for controlling plasma lipid levels. It regulates the supply and balance of low-density lipoproteins and chylomicrons. Interestingly, a high content of these substances contributes to the development of atherosclerotic vascular lesions. That is, indirectly, a normal level of hepatic lipase acts as a factor in the prevention of the development of atherothrombosis. Intestinal lipase, after being released and combined in the gastrointestinal tract with the pancreatic fraction, ensures the breakdown and absorption of fat-soluble vitamins.
In a biochemical blood test, it is possible to clarify the content of only the pancreatic fraction, since the rest cannot even be determined quantitatively due to the very small persistent volume in the bloodstream.
Therefore, the reason for taking blood is most often a specific diagnosis of pancreatic diseases - most often chronic pancreatitis. Sometimes several procedures are carried out at different times to find out the dynamics of the process and the effectiveness of the prescribed treatment.
Lipases are enzymes, i.e. proteins that perform one very precise task: they accelerate the breakdown of triglycerides (fats), from which glycerol and fatty acids are released.
Lipases are produced in our body and act throughout the digestive tract: mouth, stomach, intestines, as well as in the liver, blood, specialized cells (adipocytes, which store fat) and cellular organelles (lysosomes).
There are several types of lipase, which are classified depending on their location and purpose of action.
Let's look at the main ones:
- lingual lipase and salivary lipase: begins the breakdown of fats from the very first moments of digestion, i.e. in the oral cavity.
- Gastric lipase: present in gastric juice, where the environment is very acidic. In an adult, it breaks down up to 30% of triglycerides obtained from food, because pancreatic lipase does most of the work in the next step. In newborns, on the contrary, gastric and lingual lipases are particularly active, since the pancreas is not yet active enough.
- Pancreatic lipase: The pancreas is the main producer of lipase. This enzyme from the pancreatic juice enters the duodenum, where it forms fatty acids that are easily absorbed by the intestinal walls. The pancreas also produces colipase, another protein that binds other lipases and makes them more effective.
- Hormone Sensitive Lipase: This is the enzyme responsible for lipolysis, i.e. breaking down fats in adipose tissue cells (this lipase is found right inside adipocytes) to mobilize these reserves for energy. The enzyme's name reflects its close dependence on hormones such as epinephrine and norepinephrine, which activate it, and insulin, which inhibits the action of lipase to promote triglyceride formation and fat storage.
- lipoprotein lipase: located at the level of the capillary walls and also responds to the presence of certain hormones.
The name is due to the specific action of the enzyme on triglycerides transported into the blood. There are two forms of lipoprotein lipase: - Adipose tissue lipoprotein lipase: activated by insulin, breaks down triglycerides into fatty acids, which accumulate in adipocytes (that is, the action is almost opposite to hormone-sensitive lipase).
Lipoprotein lipase from skeletal muscle tissue and the heart: activated by glucagon and adrenaline (and inhibited by insulin), affects the hydrolysis of LDL triglycerides for energy.
Lipase test
Lipase analysis is carried out in two cases:
- To detect pancreatitis (inflammation of the pancreas).
- To evaluate the effectiveness of treatment of pancreatitis.
A blood test for lipase is considered more informative for the diagnosis of acute pancreatitis than the determination of amylase in the blood. However, in the later stages of acute pancreatitis, lipase levels may decrease. With uncomplicated mumps (the so-called “mumps”), its level remains within normal limits and increases only if the disease affects the pancreas. This is also possible in acute or chronic kidney diseases, although the increase in amylase in this case is more pronounced. So, we looked at the enzyme called “lipase” - what it is and what functions it performs in the body. Let's look at the blood test for lipase.
What is the norm
Determining the level of the enzyme in a biochemical blood test is especially important when changes occur in the organs of the digestive tract.
- In children, levels range from zero to 130 units per milliliter of blood.
- In adult men (persons over 17 years of age) – from 0 to 190 units per milliliter. The norm for women is the same.
The analysis shows only the level of pancreatic enzyme, since the enzyme produced by other organs is found in the blood in small quantities.
How to prepare for the analysis?
Blood is donated strictly on an empty stomach; you can only drink water before taking the test. At least 8-12 hours should pass after the last meal. It is better to do this before starting to take medications or 1-2 weeks after stopping them. If this is not possible, before donating blood, you should inform about what medications are being used.
The day before taking blood, you should go on a light diet - exclude fatty, fried, spicy foods, alcohol, and also avoid heavy physical activity. It is recommended to donate blood before other studies - fluorography, radiography - or physiotherapeutic procedures.
What does an increase in lipase levels in the blood indicate?
What does an increase in the level of an enzyme called lipase indicate? The normal level of its content indicates that everything is in order with the pancreas, but if the levels are elevated, this may indicate the following diseases:
- Acute pancreatitis or exacerbation of a chronic disease.
- Biliary colic.
- Chronic pathologies of the gallbladder.
- Injuries of the pancreas.
- The presence of neoplasms in the pancreas.
- Blockage of the pancreatic ducts (stone or scar).
- Intrahepatic cholestasis (and decreased flow of bile into the duodenum).
- Acute intestinal obstruction.
- Intestinal infarction.
- Peritonitis (inflammation of the peritoneum).
- Perforated stomach ulcer.
- Perforation of a hollow organ.
- Liver pathology, acute or chronic.
- Epidemic parotitis (“mumps”), causing complications on the pancreas.
- Metabolic disorders, which is usually observed with gout, diabetes, obesity.
- Cirrhosis of the liver.
And sometimes lipase increases during organ transplantation and long-term use of medications, such as barbiturates, narcotic analgesics, indomethacin, heparin.
Pancreatic lipase also increases with injuries to long bones. However, since the lipase test cannot provide the necessary information about physical damage, this indicator is not taken into account for fractures.
But in case of damage to the pancreas, analysis of lipase and amylase is very important. Their simultaneous increase with a high level of accuracy indicates a pathological process occurring in the cells of the gland. During normalization of the patient's condition, the amylase level returns to normal faster than the lipase level.
Role in the human body
The enzyme lipase is natural for our health. Therefore, its use in cheese production is completely safe and even beneficial. It is found in the liver, pancreas, intestines, at the base of the tongue and even in the lungs. The enzyme contains several enzymes, each of which is responsible for a specific segment of fats.
A deficiency or excess of this complex enzyme indicates the presence of pathologies or diseases of the liver, pancreas, kidneys, malignant neoplasms, stomach and other internal organs. The main functions look like this.
- Due to it, fats are processed and fractionated. This is necessary for normal digestion and absorption of food.
- Lipase promotes better absorption of essential vitamins such as A, E, D.
- Participates in energy metabolism.
- The enzyme produced by the pancreas is supplied to the duodenum. Under the influence of other elements, it is activated and the functioning of the entire gastrointestinal tract is normalized.
