Chemistry

Arachidonic acid


Area of ​​Expertise - biochemistry

Arachidonic acid is the common name of Δ5, Δ8, Δ11, Δ14-Eicosantetraenoic acid, a four times unsaturated fatty acid with 20 C-atoms. It is of particular importance in lipid metabolism because it is the precursor substance for various groups of signaling molecules. The prostaglandin synthase converts it into prostaglandin H2, which in turn is the starting point for the biosynthesis of thromboxanes, prostacyclin and other prostaglandins. On the other hand, lipoxygenases catalyze the conversion of arachidonic acid into hydroperoxyeicosantetraenoic acids (HPETE), from which the leukotrienes and lipoxins arise through further enzymatic conversions (arachidic acid cascade).

Arachidonic acid occurs as a component of phospholipids and diacylglycerols, from which it can be released by the action of phospholipases and diacylglycerol lipases. The human body can synthesize arachidonic acid from linoleic acid, an essential fatty acid. Occasionally, arachidonic acid itself is considered essential if there is insufficient dietary intake of linoleic acid.

See also: eicosanoids

Learning units in which the term is dealt with

2.1 - 2.5 - aspirin (total)100 min.

PharmacydrugThematic trip active ingredients

The sections of this learning unit describe the historical context and the discovery of aspirin by Felix Hoffmann, as well as the areas of indication for aspirin that were newly discovered in the course of the 20th century. After a detailed treatment of the biochemical basis of the aspirin effect by inhibiting the cyclooxygenase in the arachidonic acid metabolism, an explanation of the medical-chemical connections between the indication areas pain, inflammation, fever as well as cardiovascular diseases and the aspirin effect follows. It concludes with an extensive chapter in which the structure of cyclooxygenase and the molecular interactions between aspirin and cyclooxygenase are described.

2.4 - Aspirin - cyclooxygenase90 min.

PharmacydrugThematic trip active ingredients

This learning unit describes in detail the structure of cyclooxygenase (COX), the target enzyme in aspirin, and its active center. The following explains how the natural substrate of the COX, the arachidonate, gets to and into the COX. Furthermore, the mechanisms of the partial reactions catalyzed by cyclooxygenase, the cyclooxygenase or COX mechanism and the peroxidase or POX mechanism, are explained in detail. Finally, the cyclooxygenase and peroxidase reactions are formulated in the form of catalytic cycles and their connection to a large catalytic cycle is shown.

Eicosanoids40 min.

BiochemistrySignal and substance transportMessenger substances

In this learning unit, the structure and function of eicosanoids (prostaglandins, prostacyclines, thromboxanes and leukotrienes) in the mammalian organism is presented.

2.2 - Aspirin - Prostaglandins30 min.

PharmacydrugThematic trip active ingredients

This learning unit describes the structures, the biosynthesis and the effects of prostaglandins and thromboxanes as well as prostaglandins and thromboxanes as part of the substance class of the eicosanoids.