Linoleic acid (LNA) is a polyunsaturated fatty acid (PUFA) precursor to the longer n−6 fatty acids commonly known as omega-6 fatty acids. Omega-6 fatty acids are characterized by a carbon-carbon double bond at the sixth carbon from the methyl group. Similarly, the PUFA alpha-linoleic acid (ALA) is the precursor to n-3 fatty acids known as omega-3 fatty acids which is characterized by a carbon-carbon double bond at the third carbon from the methyl group. Both LNA and ALA are essential dietary requirements for all mammals since they cannot be synthesized natively in the body. Both undergo a series of similar conversions to reach their final fatty acid form. LNA enters the cell and is catalyzed to gamma-linolenic acid (GLA) by acyl-CoA 6-desaturase (delta-6-desaturase/fatty acid desaturase 2). GLA is then converted to dihomo-gammalinolenic acid (DGLA) by elongation of very long chain fatty acids protein 5 (ELOVL5). DGLA is then converted to arachidonic acid (AA) by acyl-CoA (8-3)-desaturase (delta-5-desaturase/fatty acid desaturase 1). Arachidonic acid is then converted to a series of short lived metabolites called eicosanoids before finally reaching it's final fatty acid form.

Alpha Linolenic Acid and Linoleic Acid Metabolism References