Metabolism is the conversion of biochemical substances by the enzyme system of organisms. Intermediates, also known as metabolites, are formed. The entire metabolism is based on the continuous metabolization of chemical substances.
What is metabolization?
The term metabolization is used in biology and medicine to describe the conversion or breakdown of a chemical substance as part of metabolism. The term metabolization is used in biology and medicine and refers to the conversion or breakdown of a chemical substance as part of metabolism. In Greek, the term metabolism is also referred to as metabolism. Metabolism is necessary to maintain the vital functions of the organism. There are the so-called catabolic and anabolic metabolism. In catabolic metabolism, for example, energy-rich high-polymeric biomaterials from food are broken down with the release of energy. The degradation takes place in three stages. First, the individual building blocks are formed from polysaccharides (multiple sugars), fats and proteins. In the case of polysaccharides, these are the hexoses (glucose, fructose) and pentoses. Fats are broken down to fatty acids and glycerol, and proteins in turn are the source of individual amino acids. All of these monomers represent metabolites of metabolism, as they can either be broken down further or contribute back to building up the body’s own biomaterials. Anabolic metabolism provides for the buildup of endogenous complex compounds from simpler starting materials. The metabolites of catabolic metabolism are called catabolites and those of anabolic metabolism are called anabolites. The interface from anabolic to catabolic metabolism is the so-called intermediate metabolism. Many metabolites are the starting material of both anabolic and catabolic processes. Foreign substances are also metabolized in the body and converted into a water-soluble excretable form. These foreign substances include drugs, but also toxins.
Function and task
Metabolization is of great importance to the body. The body is supplied with energy through the constant transformation of substances (during the degradation of energy-rich high-molecular-weight biomolecules). The chemical energy of the initial compounds is released and converted into heat and kinetic energy to maintain bodily functions. In the process, carbon dioxide and water are produced at the lowest end of the catabolic processes. This degradation takes place via several intermediate substances, which can also be reincorporated into anabolic bodily processes as so-called metabolites. The energy released during the degradation processes is temporarily stored in a phosphate bond (see ATP, GTP or others). By breaking the phosphate bond, energy is released that can be converted back into chemical energy of a macromolecule in an anabolic process. Catabolic and anabolic metabolic pathways are therefore closely linked. Furthermore, each step of a catabolic or anabolic metabolic pathway produces metabolites that are either degraded or used to build more complex compounds. The metabolic pathway from which the individual metabolite originates is not critical. This interface of catabolic and anabolic metabolism is called intermediate metabolism. The organism is always in a steady-state equilibrium from chemical substances supplied to chemical substances removed. In this process, animal organisms use chemical energy from organic substances, breaking them down into simple inorganic substances. Plant organisms absorb solar energy in the form of light and convert it into chemical energy by building up organic substances from inorganic substances. In addition to metabolization as part of normal metabolism, ingested foreign substances are also metabolized. These metabolizations always take place in the liver. These are mostly detoxification reactions. Pharmaceuticals are also subject to these reactions. Overall, this is referred to as biotransformation. In a first phase, oxidation or reduction reactions or hydrolysis take place. In the case of a primarily acting toxin or a primarily acting drug, the effect decreases in the process. However, if the pharmaceutical is ingested as a prodrug, efficacy develops only after the phase 1 reactions. The same can happen with a primarily nontoxic substance.Some toxins first develop in the body through corresponding metabolizations. The metabolites formed in phase 1 are made water-soluble in a second phase by further transformations so that they can be excreted by the kidneys.
Diseases and disorders
In the context of metabolism and the corresponding metabolizations, significant health problems can occur if a metabolite either cannot be broken down or is poorly broken down. On the contrary, if the reactions to form certain important metabolites fail to occur, health consequences can be expected as well. Very often, in such situations, a genetic defect or chromosomal alteration is present. Certain enzymes cannot be produced or can only be produced inadequately. The same effect is also caused by a defective enzyme. Thus, many metabolic diseases show an accumulation of certain metabolites. In other diseases, important metabolites are not produced at all. In both cases, the chain of complex reactions is interrupted and reactions, some of which are vital, no longer take place. In so-called storage diseases, certain substances or metabolites accumulate more and more in the cells or even outside the cells. This often leads to considerable organ damage. In the case of poisons and pharmaceuticals, metabolization should usually lead to the degradation of the substances while weakening their effect. However, there are also cases where the metabolization processes result in the formation of active metabolites from relatively harmless starting substances, which only develop their poisonous effect at this stage. The metabolization processes for foreign substances are non-specific and therefore always follow a single pattern. Therefore, it may sometimes be the case that the metabolization process of these specific substances is the real problem.
