Tissue lipoprotein lipase activity

Brewster DW, Matsumura F. 1988. Reduction of adipose tissue lipoprotein lipase activity as a result of in vivo administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin to the guinea pig. Biochem Pharmacol 37 2247-2253. 

Chylomicrons are triglyceride rich and contain apolipoprotein B-48 and the A types. The latter are synthesized in the intestinal tract cells. Additional apoproteins are transferred to the chylomicrons from HDL in circulation the apoE and apoC types. Their site of synthesis is the liver. The chylomicrons are subject to degradation by lipoprotein lipase in the peripheral tissue, especially adipose tissue. Lipoprotein lipase activity is increased by increased blood insulin levels. This enzyme is extracellular, attached to the capillary endothelial cells, and activated by ApoC-II, which is present in the chylomicrons. Lipoprotein lipase causes the hydrolysis of triglycerides, thus decreasing chylomicron size... 

Berger, G, M, (1906), Clearance defects in primary chylomicronemia A study of tissue lipoprotein lipase activities, iMetaboIiim 35, 1054-1061. 

Pectins and Guar Gum Effect on Plasma Lipoproteins and Tissue Lipoprotein Lipase Activity in Rats... 

To throw some light upon mechanisms by which dietary fiber could influence plasma lipoproteins, heart and adipose tissue lipoprotein lipase activities were measured after feeding some of the dietary fiber containing diets. This key enzyme in lipoprotein metabolism is one of the most important factors determining plasma triglyceride and plasma HDL concentrations (16). 

The increase in HDL and total cholesterol in the group fed bran did not seem related to dietary cholesterol. The increase in heart tissue lipoprotein lipase activity indicates an increased peripheral elimination of triglycerides in muscular tissue which is consistent with an elevation in HDL cholesterol. This increase, however, is small compared with changes in lipoprotein lipase activity induced by for instance ethanol (28). It is therefore more probable that the effect of wheat bran on HDL cholesterol is also related to altered rate or site of lipid absorption in the intestine. 

In the capillaries of these tissues, the extracellular enzyme lipoprotein lipase, activated by apoC-II, hydrolyzes triacylglycerols to fatty acids and glycerol (step... 

Decreased uptake of fatty acids In fasting, lipoprotein lipase activity of adipose tissue is low. Consequently, circulating triacyl-glycerol of lipoproteins is not available for triacylglycerol synthesis in adipose tissue. 

Topiramate, felbamate, and zonisamide are associated with weight loss. In animals topiramate reduced food intake, but also reduced energy disposition in the absence of reduced intake. In addition, topiramate increased lipoprotein lipase activity in adipose tissue, possibly reflecting enhanced regulatory thermogenesis. In humans and animals topiramate reduces leptin concentrations. With felbamate weight loss is almost always associated with... 

In six patients with renal transplants treated with sirolimus, mean total plasma cholesterol, triglyceride, and apolipoprotein concentrations increased (1067). The authors suggested that sirolimus increases lipase activity in adipose tissue and reduces lipoprotein lipase activity, resulting in increased hepatic synthesis of triglycerides, increased secretion of VLDL, and increased hypertriglyceridemia. 

Hamosh, M., Clary, T.R., Chernick, W.W., Scow, R.O. 1970. Lipoprotein lipase activity of adipose and mammary tissue and plasma triglyceride in pregnant and lactating rats. Biochim. Biophys. Acta 210, 473 182. 

Lipoprotein lipase activity Increase Adipose tissue... 

Decreased lipoprotein lipase activity in muscles and adipic tissues Also, the liver is strongly affected and the main hepatic changes include ... 

The rate of triglyceride output from the plasma is mainly controlled by the lipoprotein lipase activity of peripheral tissues. Post-heparin plasma lipolytic activity in vitamin-C-deficient guinea pigs decreases considerably. In addition, in some of the animals the response of the plasma lipolytic activity to intravenously administered heparin is also prolonged (45). Similar results have been reported in vitamin-C-deficient baboons (46). 

Figure 2. A negative correlation between lipoprotein lipase activity in epididymal fat tissue and triglyceride concentration in blood serum of conrtol male guinea pigs (0.5% i.-ascorbic acid in diet) and in guinea pigs with a marginal vitamin C deficiency (0.5 mg of i.-ascorbic acidjanimaljd). Equation of the...

GIP stimulates insulin secretion only in the presence of mild to moderate hyperglycaemia (Andersen et al., 1978 Wahl et al., 1992), but not in the presence of normal glucose concentrations. In addition to secretion of insulin, GIP augments insulin-dependent inhibition of hepatic glycogenolysis (Elahi et al., 1986 Hartman et al., 1986). It also activates adipose tissue lipoprotein lipase (Eckel et al., 1978) and has been shown to stimulate fatty acid synthesis de novo in rat adipose tissue (Oben et al., 1991). 

IDL) to LDL, and probably also by maintaining lipoprotein lipase activity which promotes triglyceride clearance. In liver, kidney, skeletal muscle, cardiac muscle, and adipose tissue, thyroid hormone stimulates Na", K+-ATPase gene expression and promotes thermogenesis. 

Horwitz, B.A., Inokuchi, T., Wickler, S.J. Stern, J.S. (1984) Lipoprotein lipase activity and cellularity in brown and white adipose tissue in Zucker obese rats. Metabolism 33, 354—357. 

F30. Fried, S. K., and Zechner, R. Cachectin/tumor necrosis factor decreases human adipose tissue lipoprotein lipase mRNA levels, synthesis, and activity. J. Lipid Res. 30, 1917-1923 (1989). 

In the capillaries of these tissues, the extracellular enzyme lipoprotein lipase, activated by apoC-II, hydrolyzes triacylglycerols to fatty acids and glycerol (step ), which are taken up by cells in the target tissues (step (7)) In muscle, the fatty acids are oxidized for energy in adipose tissue, they are reesterified for storage as triacylglycerols (step (8)). 

Kem PA, Ong JM, Bahman S, Carty J. The effects of weight loss on the activity and expression of adipose-tissue lipoprotein lipase in very obese humans. N Engl J Med 1990 322 1053-1059. 

Insulin increases glucose uptake, and also promotes fatty acid uptake by enhancing lipoprotein lipase activity in adipocytes. Insulin inhibits lipolysis through the inhibition of hormone-sensitive lipase in adipose tissue [10]. 

Within the developing embryo, lipoprotein lipase activity is high in both heart and adipose tissue at EI4 but is absent from liver and brain. A big increase in activity occurs in adipose tissue between EI2 and EI6 and this coincides with the period of lipid uptake from the yolk and deposition in the adipocytes. More than 90% of the energy required by the developing embryo is obtained from oxidation of fatty acids present in yolk triglycerides. A further increase in lipoprotein lipase activity also occurs on hatching (Speake, Noble McCartney, 1993). 

Speake, B.K., Noble, R.C. McCartney, R. (1993). Tissue-specific changes in lipid composition and lipoprotein lipase activity during the development of the chick embryo. Biochim. Biophys. Acta, 1165, 263-70. 

Plasma lipids were analysed as in Experiment 1. Lipoprotein lipase activities in adipose tissue and heart muscle was assayed with tri ( H) oleoylglycerol emulsion as substrate (23). Activities are expressed as nmol of fatty acid released per minute per mg protein. 

Lipoprotein lipase activity in heart tissue was not altered by pectin but slightly increased in the wheat bran group. In adipose tissue the activity was significantly lowered in the group fed pectin. 

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