Arachidonic acid

Arachidonic acid (ARA) is a 20-carbon chain fatty acid with four methylene-interrupted cis double bonds, the first with respect to the methyl end (omega, ω or n) is located between carbon 6 and 7. Therefore, arachidonic acid belongs to the omega-6 (n-6) polyunsaturated fatty acids (PUFA).

It is considered an "essential" fatty acid because it is an absolute requirement for the proper functioning for the human body. Arachidonic acid is representing 7% to 10% of total circulating fatty acids; it is the second most abundant omega-6 fatty acid in the human body.

Arachidonic acid is naturally found incorporated in the structural phospholipids in the cell membrane in the body or stored within lipid bodies in immune cells. It is particularly abundant in skeletal muscle, brain, liver, spleen and retina phospholipids.

It is synthesized from α-linolenic acid derived from linoleic acid, an essential fatty acid, by the enzyme Δ6-desaturase. Once formed, arachidonic acid can be converted to any of the eicosanoids.

Arachidonic acid is involved in several biological processes, either in health or disease. Arachidonic acid influences cell membrane fluidity and permeability and modulates platelet function and immune system activation; furthermore, it affects glomerular and tubular function, the physiopathology of podocyte, and the process of renal fibrosis.

Arachidonic acid is obtained from food such as poultry, animal organs and meat, fish, seafood, and eggs, and is incorporated in phospholipids in the cells’ cytosol, adjacent to the endoplasmic reticulum membrane that is studded with the proteins necessary for phospholipid synthesis and their allocation to the diverse biological membranes.
Arachidonic acid