NEFA - Non-esterified fatty acids

NEFA - Non-esterified fatty acids>

Extract:

Non-esterified ("free" or unsaturated) fatty acids (NEFAs) are the major component of triglycerides (the fat stores in the body), which consist of three fatty acids linked to a glycerol backbone.

Hydrolysis of stored triglycerides (fat) in adipose tissue by hormone sensitive lipase liberates NEFAs and glycerol.  Hormone sensitive lipase (which is found within the cytosol of adipocytes) is stimulated by various hormones, including glucagon (which is released from α-cells in pancreatic islets in response to low glucose). 

NEFAs can be used as an energy source by many tissues, including skeletal muscle and hepatocytes. In hepatocytes, their fate differs depending on energy needs, hormone balance and substrate availability (see figure below), i.e. they can be used for energy production, re-packaged into triglycerides and exported as very low density lipoproteins (VLDL) or stored within the liver, or converted to ketones.