Anabolism: Function, Tasks, Role & Diseases

Anabolism refers to anabolic metabolic processes in the organism. Thereby, anabolic and catabolic metabolic processes are closely connected. A build-up of substances always consumes energy.

What is anabolism?

Anabolism characterizes the build-up of energy-rich and complex compounds from simple molecules under energy input, e.g. in the intestine. Anabolism and catabolism are always linked in metabolic processes. Anabolism characterizes the building of energy-rich and complex compounds from simple molecules under energy supply. For example, photosynthesis in plants is an anabolic metabolic process. In this process, simple compounds such as water, carbon dioxide and minerals are converted into carbohydrates, proteins and fats with the help of solar energy. However, not only in plants, but also in animal and human organisms, anabolic metabolic processes are constantly taking place. In part, the term anabolism is fuzzily defined. However, the building up of compounds under energy consumption crystallizes as a common criterion of the definition. In the animal and human organism, energy-rich complex molecules such as carbohydrates, proteins and fats are also built up under energy consumption. At the same time, however, humans and animals take in carbohydrates, proteins and fats with their food beforehand, and these are broken down under energy expenditure. These catabolic metabolic processes generate energy for life processes and at the same time, in addition to water and carbon dioxide, also simple organic degradation products, such as pyruvate, which can be used again as starting materials for building up the body’s own substances. However, this requires energy, which is obtained from the catabolic metabolic processes and transferred to the new compounds via the intermediate energy store ATP.

Function and task

Anabolism is essential for the organism. In a narrow sense, anabolism refers to the building of muscle proteins. However, it refers to all anabolic processes that produce the body’s own proteins, fats and carbohydrates. These do not always have to be complex compounds. Even the new synthesis of a glucose molecule from the intermediate pyruvate is already an anabolic process. This is because energy is required for this. The build-up of endogenous substances is intended, on the one hand, to build up the structure and growth of the body and, on the other hand, to store energy. To build up the body, mainly proteins and their basic building blocks, the amino acids, are needed. The amino acids come from the breakdown processes of the proteins ingested with food. In an anabolic process, the individual amino acids are reassembled to form the body’s own proteins. Amino acids that are not needed are further converted to simple compounds such as carbon dioxide, water, urea, or to metabolic metabolites such as pyruvate. Pyruvate can be further degraded or used as a starting compound to form glucose, amino acids or fatty acids. In this way, it is possible for amino acids to be converted to glucose. In this process, catabolic and anabolic processes are linked. Glucose can be stored in the polymeric storage form glucogen in the liver and muscles. Glucogen serves as a potential energy store on demand. The newly formed fatty acids can be converted to fat by esterification with glycerol, which is stored in adipocytes as an energy reserve. All anabolic processes require energy, which is provided by the intermediate energy store ATP. ATP is always generated from ADP under energy uptake by further binding of a phosphate group. This energy comes from catabolic metabolic processes. The complex metabolic processes in the body are controlled by hormones. There are hormones that promote catabolism, such as thyroid hormones, or hormones that promote anabolism. These include insulin, the growth hormones or the sex hormones. Anabolic processes can also cause catabolic processes and vice versa. For example, muscle gain promotes fat loss. On the other hand, muscle loss is often associated with fat gain.

Diseases and ailments

Diseases related to anabolism are often caused by hormone imbalances. Hormone imbalances can be due to both internal and external causes. A well-known example of an external cause is the abuse of anabolic steroids.Anabolic steroids are often used by competitive and strength athletes to promote muscle building. They are hormone-like substances or even hormones. A commonly used anabolic steroid is the male sex hormone testosterone. Testosterone promotes muscle building in both men and women. However, many consequential damages have become known. In men, constant hormone administration reduces the production of the body’s own testosterone. After discontinuation of the anabolic steroid, there is a rapid decline in performance and muscle loss. The body’s own hormone synthesis is no longer stimulated. The result is, among other things, testosterone deficiency with poor performance, breast enlargement in men, psychological problems, degradation of the skeletal and musculoskeletal system, increased risk of heart attack and stroke, liver damage, and shrunken testicles with the development of infertility. In women, the menstrual cycle may be disturbed. Furthermore, the clitoris enlarges. If anabolism is disturbed by internal causes, hormonal imbalances often play a role. These can be hereditary or caused by serious diseases of the hormone-producing glands. Typical examples are the deficiency as well as the overproduction of the growth hormone somatropin. If somatropin deficiency already exists in childhood, short stature results. Overproduction results in giant growth and, in adulthood, acromegaly, which is associated with excessive growth of the hands, feet, ears, nose, chin or external genitalia. In the case of underactivity in adulthood, increased muscle and bone loss results. At the same time, however, fat tissue increases. In the so-called cushioning syndrome, the body’s own proteins are also increasingly broken down. At the same time, however, fat build-up occurs in the form of truncal obesity. Here, the hormone cortisol is increased, which promotes the conversion of amino acids into glucose.