Exercise hormone-sensitive lipase

The hydrolysis of TGs to FFAs and glycerol is catalyzed by a lipase in adipocytes called hormone-sensitive lipase. This enzyme catalyzes the hydrolysis of fat deposits in adipose tissue or wherever adipocytes arc found. The rate of liberation of fatty adds and of the byproduct glycerol from the adipose tissue may be greater than the rate at which they can be oxidized by other tissues. Under these conditions, the concentrations of FFAs and glycerol increase in the plasma. The data in Table 4.9 are from a study of human subjects who exercised on a stationaiy bicycle. Blood samples withdrawn during rest and at the indicated times during exercise show that FFA concentrations increased from 0 43 mM at rest to nearly 2.0 mM after 3 hours of work. 

L. Enevoldsen, B. Stallknecht, (. Langfort, L. Petersen, C. Holm, T. Ploug, and H. Galbo, The effect of exercise training on hormone-sensitive lipase in rat intra-abdominal adipose tissue and muscle, J. Physiol., 2001, 536, 871-877. 

During fasting or exercise and at times of stress, lipid is used as a source of energy. Hormone-sensitive lipase catalyzes the sequential hydrolysis of triacylglycerol to... 

The availability of free fatty acids in the blood, which depends on their release from adipose tissue triacylglycerols by hormone-sensitive lipase. During prolonged exercise, the small decrease of insulin, and increases of glucagon, epinephrine and norepinephrine, cortisol, and possibly growth hormone all activate adipocyte tissue lipolysis. 

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