synthesis

In the synthesis the human organism itself produces essential substances. Important syntheses are, for example, protein synthesis and cholesterol synthesis. Disrupted synthesis pathways have far-reaching consequences and can occur in the context of various deficiency symptoms, organ damage and diseases.

What is the synthesis?

Chemical synthesis is the reaction-related assembly of atoms and molecules to form larger compounds. In medicine, for example, the term synthesis refers to biochemical processes in the cells of the body. Well-known syntheses in the human organism are, for example, processes such as protein synthesis, fatty acid synthesis, ATP synthase and hormone synthesis.

Each of these processes corresponds to a chemical reaction in which relatively simple and easily available starting materials result in a comparatively complex, often less available end product. The expression of biosynthesis refers to more concrete metabolic reactions that build up chemical compounds. These processes are also summarized under the term anabolism. Foreign substances from everyday food are broken down and converted into the body's own substances. This is how, for example, body components such as amino acids, proteins, carbohydrates, fats and hormones or nucleic acids are created.

A distinction must be made between these definitions of synthesis and osteosynthesis, in which a bone is assembled from bone fragments.

Function & task

The body knows five essential groups of substances: proteins, carbohydrates, vitamins, minerals and fats. The organism itself synthesizes some of these substances from more or less simple raw materials. Syntheses are anabolic metabolic processes and produce substances that are required by the body to build cells, to stimulate body organs, for metabolic processes or to supply energy.

Protein synthesis is one of the most important synthesis processes in the human organism. There are 50,000 to 100,000 proteins in a human body. They fulfill vital functions, build cells and repair defects. Proteins arise from a combination of different amino acids in the so-called ribosomes. In protein synthesis, the organism strings these amino acids on strings and connects them with one another as if they were links in a chain. The resulting chains are called polypeptides. The red pigment of the blood cells, the neurotransmitters for the transmission of nerve impulses or the building blocks of RNA and DNA are also synthesized from amino acids.

Amino acids are involved in the synthesis of the thyroid hormone thyroxine, for example. This hormone and its derivatives are made from the amino acid tyrosine. Enzymes are also synthesized from polypeptide chains and sometimes several protein chains. They act as catalysts in the organism and thus accelerate biochemical reactions, for example.

For some syntheses, in addition to enzymes, starting compounds such as vitamins are necessary. These vitamins are among the essential substances. The human organism cannot synthesize them itself. Therefore, vitamins must be taken through food. However, some nutritional vitamins only correspond to preliminary stages of the vitamins that can actually be used and are converted in the body in more or less complex processes before further use.

Minerals cannot be synthesized either. The inorganic substances are present in the body either as bulk or trace elements and, like vitamins, are absorbed with food. In contrast, the body can synthesize the equally vital fatty acids from food. Carbohydrates are the starting material.

Illnesses & ailments

An innumerable number of diseases can lead to a disturbed synthesis of various reaction pathways. Disturbances can affect hemoglobin synthesis, for example. The concentration of the red blood pigment is reduced as a result of a synthesis disturbance, which is to be understood as hypochromic anemia. One cause of this form of anemia can be an abnormal iron distribution, as divalent iron molecules are required for synthesis.

Disorders can also occur in the synthesis of erythrocytes, for example due to insufficient vitamin B12 intake. In both cases, malnutrition is responsible for the synthesis disturbance.

Since an enormous number of syntheses in the human organism take place specifically in the liver cells, liver diseases or damage are also possible triggers for disturbed synthesis processes. The liver intervenes in most of the vital metabolic pathways and is therefore involved in most of the synthesis. In addition to glycogen synthesis, the synthesis of plasma proteins, coagulation factors and apolipoproteins takes place here. The biosynthesis of non-essential amino acids also takes place mainly in the cells of the liver.

The same applies to the synthesis of urea and the substances creatine and glutathione. In addition, the liver is involved in the synthesis of fatty acids, fats and lipoproteins and also synthesizes phospholipids and cholesterol. Ultimately, the synthesis of complement factors, acute phase proteins and insulin growth factors also takes place in this organ. In addition, the erythropoietins, thrombopoietins and angiotensinogens are made in the liver. If one of these syntheses is subject to a disruption or if all of the above-mentioned synthesis pathways are disrupted, this can be due to severe liver damage.

Such liver damage can occur in the context of alcohol abuse, drug or medication abuse as well as other types of poisoning and various diseases.

Of course, other organs are also involved in syntheses. For example, kidney damage can become noticeable through disturbances in calcitriol synthesis. A disturbed calcitriol synthesis can just as well indicate a vitamin deficiency. The causes and effects of disturbed synthesis pathways are accordingly diverse.