Nonesterified Fatty Acids (NEFAs), also known as Free Fatty Acids (FFAs), are a type of fatty acid that circulate in the bloodstream without being attached to a glycerol molecule. They play a crucial role in energy metabolism, serving as a major energy source during fasting or periods of increased energy demand.
NEFAs can be derived from the breakdown of stored triglycerides in adipose tissue, and they are also released in response to various physiological conditions, including stress, exercise, and fasting.
They are involved in various biological processes, including energy production, signaling pathways, and lipid metabolism, making them important biomolecules in the body's overall functioning.
Nonesterified Fatty Acids or free fatty acids are fundamental units in the structure of lipids in membranes and lipoproteins. Nonesterified Fatty Acids are an important source of energy for the heart and for aerobically conditioned skeletal muscle.
Plasma Nonesterified Fatty Acids concentrations are increased in three related pathologic states that tend to cluster in individuals and that have been implicated in premature coronary artery disease: obesity, type 2 diabetes and elevated plasma triglyceride.
Nonesterified Fatty Acids can be used for evaluation of metabolic status of people with endocrinopathies. It can be used for detection of Pheochromocytoma and of glucagon-, thyrotropin -adrenocorticotropin-secreting tumours. It is occasionally used for monitoring of control of diabetes mellitus.
References:
Carlsson M, Wessman Y, Almgren P, Groop L. High levels of nonesterified fatty acids are associated with increased familial risk of cardiovascular disease. Arterioscler Thromb Vasc Biol. 2000 Jun;20(6):1588-94. doi: 10.1161/01.atv.20.6.1588. PMID: 10845876.
Frayn KN. Non-esterified fatty acid metabolism and postprandial lipaemia. Atherosclerosis. 1998 Dec;141 Suppl 1:S41-6. doi: 10.1016/s0021-9150(98)00216-0. PMID: 9888641.
Nonesterified Fatty Acids (Free Fatty Acids)
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