Overexpression of Human Lipoprotein Lipase Increases Hormone-Sensitive Lipase Activity in Adipose Tissue of Mice

1. Lipoprotein lipase activity and hormone-sensitive lipase activity were investigated in subcutaneous lipomas removed from two patients and compared with the enzyme activities in subcutaneous adipose tissue from two normal subjects. 2. Confirmation was obtained of the presence of lipoprotein lipase activity in lipomas with an activity fifteen to forty-five times that in the two control samples. 3. Hormone-sensitive lipase activity was demonstrated in lipomas under basal conditions of assay as well as in the presence of adrenaline plus theophylline. However, compared with the non-lipomatous fat samples, these activities were lower, as was the magnitude of the lipolytic response to adrenaline plus theophylline. 4. The significance of these measurements of enzyme activity and their role in the pathogenesis of lipomas are briefly discussed.

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Rat adipose tissue lipases: hormone-sensitive lipase activity against triglycerides compared with activity against lower glycerides

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)40184-1 ◽

1964 ◽

Vol 5 (4) ◽

pp. 554-562 ◽

Cited By ~ 1

Author(s):

Ove Strand ◽

Martha Vaughan ◽

Daniel Steinberg

Keyword(s):

Adipose Tissue ◽

Lipase Activity ◽

Hormone Sensitive Lipase ◽

Hormone Sensitive ◽

Rat Adipose Tissue

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Effects of Physiological Hypercortisolemia on the Regulation of Lipolysis in Subcutaneous Adipose Tissue1

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jcem.83.2.4547 ◽

1998 ◽

Vol 83 (2) ◽

pp. 626-631 ◽

Cited By ~ 3

Author(s):

Jaswinder S. Samra ◽

Mo L. Clark ◽

Sandy M. Humphreys ◽

Ian A. MacDonald ◽

Peter A. Bannister ◽

...

Keyword(s):

Adipose Tissue ◽

Lipoprotein Lipase ◽

Sodium Succinate ◽

Hormone Sensitive Lipase ◽

Whole Body ◽

Constant Infusion ◽

Nonesterified Fatty Acid ◽

Significant Difference ◽

Hormone Sensitive ◽

Subcutaneous Adipose

Cortisol is known to increase whole body lipolysis, yet chronic hypercortisolemia results in increased fat mass. The main aim of the study was to explain these two apparently opposed observations by examining the acute effects of hypercortisolemia on lipolysis in subcutaneous adipose tissue and in the whole body. Six healthy subjects were studied on two occasions. On one occasion hydrocortisone sodium succinate was infused iv to induce hypercortisolemia (mean plasma cortisol concentrations, 1500 ± 100 vs. 335± 25 nmol/L; P < 0.001); on the other occasion (control study) no intervention was made. Lipolysis in the sc adipose tissue of the anterior abdominal wall was studied by measurement of arterio-venous differences, and lipolysis in the whole body was studied by constant infusion of[ 1,2,3-2H5]glycerol for measurement of the systemic glycerol appearance rate. Hypercortisolemia led to significantly increased arterialized plasma nonesterified fatty acid (NEFA; P < 0.01) and blood glycerol concentrations (P < 0.05), with an increase in systemic glycerol appearance (P < 0.05). However, in sc abdominal adipose tissue, hypercortisolemia decreased veno-arterialized differences for NEFA (P < 0.05) and reduced NEFA efflux (P < 0.05). This reduction was attributable to decreased intracellular lipolysis (P < 0.05), reflecting decreased hormone-sensitive lipase action in this adipose depot. Hypercortisolemia caused a reduction in arterialized plasma TAG concentrations (P < 0.05), but without a significant change in the local extraction of TAG (presumed to reflect the action of adipose tissue lipoprotein lipase). There was no significant difference in plasma insulin concentrations between the control and hypercortisolemia study. Site-specific regulation of the enzymes of intracellular lipolysis (hormone-sensitive lipase) and intravascular lipolysis (lipoprotein lipase) may explain the ability of acute cortisol treatment to increase systemic glycerol and NEFA appearance rates while chronically promoting net central fat deposition.

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Seasonal changes in hormone-sensitive and lipoprotein lipase mRNA concentrations in marmot white adipose tissue

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1992.262.2.r177 ◽

1992 ◽

Vol 262 (2) ◽

pp. R177-R181 ◽

Cited By ~ 9

Author(s):

B. E. Wilson ◽

S. Deeb ◽

G. L. Florant

Keyword(s):

Adipose Tissue ◽

Lipoprotein Lipase ◽

White Adipose Tissue ◽

Mass Gain ◽

The Body ◽

Hormone Sensitive Lipase ◽

Marmota Flaviventris ◽

Fasting Period ◽

Hormone Sensitive ◽

Clear Increase

White adipose tissue (WAT) and plasma samples were obtained from yellow-bellied marmots (Marmota flaviventris) throughout the year. Mean plasma triacylglycerol (TG), free fatty acids (FFAs), and glycerol were determined. There was a clear increase in FFAs and decrease in mean TG and glycerol during the hibernation period when animals were fasting, suggesting increased lipolysis. RNA was isolated from WAT biopsies at four times in the year: spring, summer, fall, and winter. There were significant changes in the relative levels of mRNA for lipoprotein lipase (LPL) and hormone-sensitive lipase (HSL) during the body mass cycle of the marmot. The relative levels of LPL mRNA are high during the mass gain phase of the year and that of HSL mRNA are high during the fasting period when endogenous lipid is utilized. These results suggest that the genes for LPL and HSL are regulated seasonally to control the adipose mass depot in marmots.

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Effect of exercise on hormone-sensitive lipase activity in rat adipocytes

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1976.230.2.385 ◽

1976 ◽

Vol 230 (2) ◽

pp. 385-388 ◽

Cited By ~ 9

Author(s):

JA McGarr ◽

LB Oscai ◽

J Borensztajn

Keyword(s):

Fatty Acids ◽

Enzyme Activity ◽

Adipose Tissue ◽

Free Fatty Acids ◽

Lipase Activity ◽

Exercise Program ◽

Treadmill Running ◽

Hormone Sensitive Lipase ◽

Hormone Sensitive ◽

Fat Pads

Hormone-sensitive lipase activity was measured in adipocytes of rats subjected to a 12-wk program of treadmill running. Enzyme activity in the runners sacrificed immediately after exercise increased 2.5-fold (P less than 0.001) in tissue exposed to epinephrine and threefold (P less than 0.001) in tissue not exposed to epinephrine, when the results were expressed per gram of adipose tissue. Increases of almost the same magnitude were observed in runners sacrificed 24 h after their last bout of work. These significant increases in enzyme activity, however, were the result of a significant reduction in the size of cells in the epididymal fat pads of the exercisers compared with those of the freely eating sedentary animals (68.7 +/- 2.7 mum vs. 82.0 +/- 2.7 mum; P less than 0.01). When the results were expressed on a per-cell basis, therefore, hormone-sensitive lipase activity, assayed in the presence or absence of epinephrine, was unaffected by the exercise program. These results provide evidence that the lipolytic capacity of adipocytes of normal, untrained rats is sufficiently large to meet the increased demand for free fatty acids imposed by the exercise program without the need for an adaptive increase in enzyme activity.

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