Alpha-linolenic acid metabolic pathway

The alpha-linolenic acid metabolic pathway describes the series of biochemical reactions by which alpha-linolenic acid (ALA), an essential omega‑3 fatty acid obtained from dietary sources such as flaxseed, chia seeds, walnuts, and certain vegetable oils, is converted into longer-chain n−3 polyunsaturated fatty acids including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Humans cannot synthesize ALA de novo due to lack of specific desaturase enzymes; thus it must be acquired through diet. The conversion process involves alternating steps of desaturation—primarily by delta‑6 desaturase and delta‑5 desaturase—and elongation within cellular organelles like the endoplasmic reticulum and peroxisomes. The products EPA and DHA have well-documented roles in reducing inflammation and lowering risks associated with chronic diseases such as cardiovascular disease and arthritis. Conversion rates from dietary ALA to EPA/DHA are generally low but higher in women than men due to hormonal influences. Genetic variability also affects individual capacity for this conversion. This entry refers specifically to a metabolic process rather than an individual molecular target like an enzyme or receptor. Therefore, it is not considered a therapeutic "target" per se but rather encompasses several potential targets within its enzymatic steps—most notably delta‑6 desaturase (FADS2) and delta‑5 desaturase (FADS1)—which may be modulated pharmacologically or nutritionally for therapeutic benefit.

Other names

ALA metabolismOmega-3 fatty acid biosynthesis pathway

Not applicable to the pathway itself. For enzymes within the pathway: - Delta‑6 desaturase and delta‑5 desaturase catalyze key steps in conversion of ALA to longer-chain omega‑3 PUFAs. - Drugs or nutrients that modulate these enzymes can affect PUFA levels.