What is cholesterol esterase?
Cholesterol esterases are enzymes that are responsible for the cleavage of cholesterol ester compounds. Cholesterol esters are composed of cholesterol and fatty acids. These are connected to each other by a certain type of bond, a so-called esterification. During the cleavage process, free cholesterol and fatty acids are created, which are usually long-chain. The cholesterol esterases occur in the body in the liver, intestine and pancreas and play a role in the absorption of food and the cholesterol metabolism in the body accordingly.
Task and function
Cholesterol esterase is an enzyme in the human body that plays an important role in the availability of cholesterol. For this purpose, cholesterol esterases cleave so-called cholesterol esters. These are compounds of free cholesterol and a fatty acid, which are bound together by an ester bond.
To split this ester bond, free water is needed. Therefore this kind of cleavage is also called hydrolysis, i.e. a cleavage with the help of water. The importance of cholesterol esterase for the body depends on its localization.
The aim of the body is to absorb cholesterol from food and store it in the liver, so that it can be released from the liver and used again when needed. As a substance, cholesterol is above all important for the formation of the cell membrane and is therefore needed almost everywhere in the body. Cholesterol also serves as a starting material for the formation of vitamin D, hormones and bile acids.
In the intestinal mucosa, cholesterol esterase causes cholesterol to be broken down from food, absorbed through the mucosa and thus enter the body’s circulation. The optimal effect of cholesterol esterases in the intestines is supported by bile acids. In order to be transported in the blood, however, the cholesterol must be repackaged after absorption into the intestinal cells.
This takes place in the form of so-called LDL particles, which ensure that the cholesterol can be transported via the blood to the liver. There it must now be released from these particles again by another cholesterol esterase so that it can be stored and the remains of the particles can be reused. The storage in the liver also takes place again in the form of esterification. If the body needs cholesterol, it can be released from the liver by cholesterol esterases from the storage form and then transported to the appropriate place with the help of other transport forms, so-called HDL particles.
Where is it made?
The enzyme cholesterol esterase is produced in the human body in the pancreas and liver. In the pancreas, the production is taken from the exocrine part of the pancreas. After the cholesterol esterase is released, it reaches the intestine where it can take up its splitting action. In the liver, the cholesterol esterase is mainly produced to store the cholesterol absorbed in the intestine.
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