What is the liver?

The liver is the largest gland in the human body, essential for metabolism. It is connected to the digestive system and performs many functions not only helpful to the digestion of food, but also to the defense mechanism of the body and the elimination of toxic substances. Therefore, in order to maintain the organism as a whole, it is essential that the liver be in good health and continuously cared for.

The liver is a large gland that is composed of four lobes. It is located in the upper right portion of the abdominal cavity and positioned below the diaphragm near the transverse colon and stomach. It has an ovoid shape, weighs about 1-1.5 pounds and is about 24-28 cm in length, making it the largest gland in the human body. The liver is connected to the hepatic artery, which is the main artery of the liver. It develops during the embryonic stage starting from the medium intestine and once the fetus is delivered, the liver is the leading producer of red blood cells.

The liver cells perform most of the functions of the organ related to its metabolic activity. They form the main structures of the liver and reach up to 80% in total volume of the organ. The stellate cells (Ito cells) perform a special function: they support the extraordinary ability of the liver to regenerate, such as after an injury of surgery. Their vitamin A collagen and retuculin “bricks” make it possible to replenish areas of damaged tissue.

The liver is a gland that is part of the endocrine system, which oversees the production of hormones. Hormones are essential substances for different functions. In particular, the liver produces bile, which is essential for the digestion of fats. The liver is also an important deposit of glycogen, which represents about 7.6% of the total weight of the liver.

The liver is a very vulnerable organ: viral infections, alcohol abuse, smoking, drugs, and excess fat can all cause damage and malfunctions. The liver cirrhosis is a disease characterized by chronic inflammation of the live. It destroys liver cells and causes scars that reduce, even irreversibly, organ function. Another disease, called fatty liver disease or fatty liver, involves the accumulation of triglycerides. Also, hepatitis, which is acute or chronic inflammation is caused by numerous viruses (HAV, HBV, HCV, HDV, HEV, HGV) between which types hepatitis B and hepatitis C are the most frequent and are transmitted through blood and serum (blood transfusions, use of infected syringes) as well as unprotected sex. Other direct threats to the body also include cancer and autoimmune diseases. 

Many antiviral therapies are proven effective in treating infections, but unfortunately there is currently no medical remedy for when the liver becomes severely damaged.  A balanced lifestyle is often recommended as the best prevention against diseases of the liver. This includes a diet low in fat and rich in fruits and vegetables and the elimination of alcohol and cigarettes.

 

What function does the liver serve?

The liver performs many important metabolic functions. It produces bile and encourages the transformation of food absorbed, in particular through the 'emulsion of fats and the synthesis of cholesterol and triglycerides. The organ also plays a role in protein metabolism, reducing toxic waste,  as well as management of sugars during storage.

Liver cells (also called hepatocytes) are a real “chemical plant” for the elimination of fat, triglycerides and cholesterol. They provide a specific cellular structure and smooth endoplasmic reticulum.

The liver produces bile, a liquid of dark yellow color mainly composed of water and bile acids that allows the digestion of fats and vitamins A, D, E, K which dissolve in fat (fat-soluble vitamins). The bile produced by the liver passes partly into the duodenum and partly into the gall bladder, which stores the bile until the moment in which the fat comes from the stomach to the bowel.  At that point, it is poured into the duodenum to allow for the synthesis of fats . Jaundice is the condition in which, for the possible presence of gallstones, bile salts remain in the liver. The most obvious symptom is unnatural yellowish discoloration of the skin.

Glycogen, vitamin B12, iron and copper are all stored in the liver. The glycogen that is stored is usually transformed into plasma glucose, whenever the body requires it. The liver performs a role in regulating blood sugar levels (glucose) as well as preserving the metabolic balance of the body, through the demolition of insulin and other transformations of protein energy. It also serves as a source of clotting factors, to keep the blood fluid and prevent any formation of aggregations that might impede the circulation.

The liver is a true filter of toxins and the central location to the immune system. Its cells have characteristics useful to neutralize toxins and residues of drugs, as well as dispose damaged red blood cells. It is home to specialized cells in recognition of pathogens, called Kupffer cells. They are also called macrophages of the liver and act as a “purification process” of the blood. They reach the liver cells and remove damaged or aged blood cells, all the while supporting the function of the spleen, whose role is to trigger the immune system to act as a defense mechanism in the presence of danger to the body.