scholarly journals Uptake of [alpha ]-tocopherol by the mammary gland but not by white adipose tissue is dependent on lipoprotein lipase activity around parturition and during lactation in the rat

Metabolism ◽  
2002 ◽  
Vol 51 (11) ◽  
pp. 1444-1451 ◽  
Author(s):  
Sonia Mart[iacute]nez ◽  
Coral Barbas ◽  
Emilio Herrera
Keyword(s):  
Adipose Tissue ◽  
Mammary Gland ◽  
Lipoprotein Lipase ◽  
White Adipose Tissue ◽  
Lipase Activity ◽  
Alpha Tocopherol ◽  
Lipoprotein Lipase Activity

scholarly journals Effects of tri-iodothyronine administration on the disposal of oral [1-14C]triolein, lipoprotein lipase activity and lipogenesis in the rat during lactation and on removal of the litter

1994 ◽  
Vol 301 (2) ◽  
pp. 495-501 ◽  
Author(s):  
M Del Prado ◽  
T H Da Costa ◽  
D H Williamson
Keyword(s):  
Skeletal Muscle ◽  
Adipose Tissue ◽  
Mammary Gland ◽  
Lipoprotein Lipase ◽  
White Adipose Tissue ◽  
Lipase Activity ◽  
Plasma Prolactin ◽  
Lipoprotein Lipase Activity ◽  
14Co2 Production ◽  
Pup Growth

The effect of tri-iodothyronine (T3) administration on the utilization of dietary [14C]lipid by the mammary gland and adipose tissue of lactating and litter-removed rats was studied. (1) After an oral load of [1-14C]triolein, the lactating rats treated with T3 (50 micrograms/100 g body wt.) over 24 h showed an increase in 14CO2 production and a decrease in the total [14C]lipid transferred through the mammary gland that was paralleled by a decrease in tissue lipoprotein lipase (LPL) activity. (2) T3 administration decreased plasma prolactin in the lactating rats. Prolactin replacement in T3-treated rats restored LPL activity in the mammary gland, but did not increase the amount of dietary [14C]lipid transferred to the milk. (3) Chronic T3 administration (4 days) to lactating rats did not affect pup growth or the lipogenic rate in the mammary gland. (4) The administration of T3 to litter-removed rats inhibited the increase of LPL activity in white adipose tissue and decreased the accumulation of dietary [14C]lipid. This decrease was accompanied by increased 14CO2 production and [14C]lipid accumulation in skeletal muscle and heart. (5) It is concluded that hyperthyroidism depresses LPL activity in mammary gland and white adipose tissue, but not in muscle. The increased accumulation of [14C]lipid in muscle and increased production of 14CO2 in lactating and in litter-removed rats treated with T3 is in part due to the decreased total LPL in mammary gland and adipose tissue respectively, which are therefore less able to compete with muscle for the available plasma triacylglycerols.

scholarly journals Effects of exogenous insulin or vanadate on disposal of dietary triacylglycerols between mammary gland and adipose tissue in the lactating rat: insulin resistance in white adipose tissue

1993 ◽  
Vol 290 (2) ◽  
pp. 557-561 ◽  
Author(s):  
T H M Da Costa ◽  
D H Williamson
Keyword(s):  
Adipose Tissue ◽  
Mammary Gland ◽  
Lipoprotein Lipase ◽  
White Adipose Tissue ◽  
Lipase Activity ◽  
Dietary Lipid ◽  
Lipid Deposition ◽  
Exogenous Insulin ◽  
Lipoprotein Lipase Activity ◽  
Stimulation Of

The effects of exogenous insulin or vanadate (an insulin mimetic) on the disposal of dietary [14C]lipid between oxidation to 14CO2, deposition in adipose tissue or uptake by mammary gland and transfer to suckling pups were studied in virgin and lactating rats. After an oral load of [1-14C]triolein, virgin rats treated with a supraphysiological dose of insulin over 24 h showed a decrease (58%) in 14CO2 production and increased accumulation of [14C]lipid in carcass and white adipose tissue. There was a 2.5-fold increase in lipoprotein lipase activity in the latter. Chronic vanadate administration (12 days) had no effect on these parameters. In lactating rats, the stimulation of the deposition of [14C]lipid in adipose tissue by exogenous insulin was about 10% of that in virgin rats. In prolactin-deficient lactating rats there was no stimulation of [14C]lipid deposition in adipose tissue by insulin. However, both insulin and vanadate treatment increased the accumulation of [14C]lipid in mammary gland to the values seen in the mammary glands plus pups of normal lactating rats. Lipoprotein lipase activity in the gland was also restored to normal values. It is concluded that in lactation there is resistance to insulin stimulation of dietary lipid deposition in adipose tissue, and that this is not due to circulating prolactin. In addition, exogenous insulin plays a role in the regulation of lipoprotein lipase and hence of dietary lipid uptake into lactating mammary gland.

scholarly journals Tissue-specific effects of rapid tumour growth on lipid metabolism in the rat during lactation and on litter removal

1988 ◽  
Vol 252 (1) ◽  
pp. 65-72 ◽  
Author(s):  
R D Evans ◽  
D H Williamson
Keyword(s):  
Adipose Tissue ◽  
Mammary Gland ◽  
Lipid Metabolism ◽  
Lipoprotein Lipase ◽  
White Adipose Tissue ◽  
Lipase Activity ◽  
Lipid Accumulation ◽  
Lipoprotein Lipase Activity ◽  
Tumour Burden ◽  
Plasma Triacylglycerol

1. The effect of tumour burden on lipid metabolism was examined in virgin, lactating and litter-removed rats. 2. No differences in food intake or plasma insulin concentrations were observed between control animals and those bearing the Walker-256 carcinoma (3-5% of body wt.) in any group studied. 3. In virgin tumour-bearing animals, there was a significant increase in liver mass, blood glucose and lactate, and plasma triacylglycerol; the rate of oxidation of oral [14C]lipid to 14CO2 was diminished, and parametrial white adipose tissue accumulated less [14C]lipid compared with pair-fed controls. 4. These findings were accompanied by increased accumulation of lipid in plasma and decreased white-adipose-tissue lipoprotein lipase activity. 5. In lactating animals, tumour burden had little effect on the accompanying hyperphagia or on pup weight gain; tissue lipogenesis was unaffected, as was tissue [14C]lipid accumulation, plasma [triacylglycerol] and white-adipose-tissue and mammary-gland lipoprotein lipase activity. 6. On removal (24 h) of the litter, the presence of the tumour resulted in decreased rates of lipogenesis in the carcass, liver and white and brown adipose tissue, decreased [14C]lipid accumulation in white adipose tissue, but increased accumulation in plasma and liver, increased plasma [triacylglycerol] and decreased lipoprotein lipase activity in white adipose tissue. 7. The rate of triacylglycerol/fatty acid substrate cycling was significantly decreased in white adipose tissue of virgin and litter-removed rats bearing the tumour, but not in lactating animals. 8. These results demonstrate no functional impairment of lactation, despite the presence of tumour, and the relative resistance of the lactating mammary gland to the disturbance of lipid metabolism that occurs in white adipose tissue of non-lactating rats with tumour burden.

scholarly journals Changes in the lipoprotein lipase (clearing-factor lipase) activity of white adipose tissue during development of the rat

1978 ◽  
Vol 172 (2) ◽  
pp. 319-325 ◽  
Author(s):  
A Cryer ◽  
H M Jones
Keyword(s):  
Enzyme Activity ◽  
Adipose Tissue ◽  
Lipoprotein Lipase ◽  
White Adipose Tissue ◽  
Lipase Activity ◽  
Plasma Insulin ◽  
Serum Concentrations ◽  
Lipoprotein Lipase Activity ◽  
Activity Change ◽  
Adipose Tissue Lipoprotein Lipase

The lipoprotein lipase (clearing-factor lipase) activity of the white adipose tissue from rats aged between 1 and 145 days was determined. Five adipose-tissue sites (epididymal, uterine, subcutaneous, perirenal and intramuscular) together with serum concentrations of triacylglycerol, cholesterol and glucose were studied. The pattern of enzyme-activity change was remarkably similar in all the sites studied, although the growth of the tissues proceeded non-uniformly. After a peak of activity early in suckling, lipoprotein lipase activity fell to low values by 20 days of age. At weaning (21 days) the activity increased sharply and within 5 days high values were regained. The serum triacylglycerol and cholesterol concentrations were low at birth and reached peaks of concentration coincidentally with the minima of white-adipose-tissue lipoprotein lipase activities, seen late in suckling. The changes in enzyme activity were related to other metabolic changes in adipose tissue and with the known changes in plasma insulin concentrations occurring during development.

scholarly journals The early development of white adipose tissue. Effects of litter size on the lipoprotein lipase activity of four adipose-tissue depots, serum immunoreactive insulin and tissue cellularity during the first four weeks of life in the rat

1979 ◽  
Vol 178 (3) ◽  
pp. 711-724 ◽  
Author(s):  
Anthony Cryer ◽  
Heather M. Jones
Keyword(s):  
Adipose Tissue ◽  
Lipoprotein Lipase ◽  
White Adipose Tissue ◽  
Lipase Activity ◽  
Nonesterified Fatty Acid ◽  
Immunoreactive Insulin ◽  
Postnatal Life ◽  
Fat Cells ◽  
Lipoprotein Lipase Activity ◽  
Fat Cell

1. Newborn rats were reared in litters of either four or sixteen individuals. The animals from the small litters gained body weight more rapidly than those from large litters during the first 29 days of postnatal life studied. 2. The relative weights of the perigenital, perirenal, subcutaneous and intramuscular white-adipose-tissue sites in the animals from small litters indicated their relative obesity compared with controls. 3. The adipose depots from animals reared in small litters had a greater proportion of lipid present, by weight, and had a greater number of larger fat-cells present in them compared with the depots of animals reared in large litters. 4. Compared with both normal-sized litter controls and animals reared in sixteens, during the period of study the animals from small litters were hypertriacylglycerolaemic but normocholesterolaemic. 5. During suckling the blood glucose concentrations of animals reared in fours were increased, as were the concentrations of circulating immunoreactive insulin. 6. During the 29 days of life studied, in general, the lipoprotein lipase activity of adipose depots from animals reared in fours was greater than for animals in large litters when expressed as μmol of nonesterified fatty acid released from the substrate/h per g fresh weight of tissue, per depot, or per million fat-cells, but were similar per cm2 of fat-cell surface area. 7. The previously noted [Cryer & Jones (1978) Biochem. J.172, 319–325] pattern of mid-suckling elevation, late-suckling decline and post-weaning increase in the lipoprotein lipase activity of the four white-adipose depots studied was not obliterated by the nutritional manipulations employed. 8. The relation of the enzyme-activity changes and their hormonal stimuli to triacylglycerol accumulation in fat-cells of animals from large and small litters is discussed in relation to the possible significance they may have to our understanding of neonatally induced obesity.

Plasma lipoprotein cholesterol and triglycerides and lipoprotein lipase activity in epididymal white adipose tissue of rats fed high sucrose or high corn oil diets

1986 ◽  
Vol 64 (7) ◽  
pp. 885-891 ◽  
Author(s):  
Yves Deshaies
Keyword(s):  
Adipose Tissue ◽  
Total Cholesterol ◽  
Lipoprotein Lipase ◽  
White Adipose Tissue ◽  
Lipase Activity ◽  
Corn Oil ◽  
Reference Group ◽  
Density Lipoprotein ◽  
Lipoprotein Lipase Activity ◽  
Adipose Tissue Lipoprotein Lipase

The present study was undertaken to compare plasma lipoprotein lipid composition, as well as white adipose tissue lipoprotein lipase activity, in rats fed purified diets high in either sucrose or corn oil. The experimental diets (65% of calories as sucrose or corn oil, 15% as the opposite nutrient, and 20% as casein) were given ad libitum for 4 weeks. An additional group was fed a nonpurified diet as a reference diet. Both sucrose and oil diets were spontaneously consumed in isocaloric amounts by the animals. Despite energy intakes that were 35% lower than that of the reference group, the sucrose and oil groups exhibited final body weights that were only 6 and 9% lower, respectively, than that of the reference group, and accumulated more fat in the epididymal depots. Postprandial as well as fasting total cholesterol levels were similar in the sucrose and oil groups, while the high-density lipoprotein to total cholesterol ratio was highest in the animals fed corn oil. In both the fasted and fed states, plasma total triglyceride levels were 73% higher in the sucrose group than in the corn oil group. The largest triglyceride differences due to diet were observed in the chylomicron + very-low-density lipoprotein fraction. The oil-fed rats accumulated large amounts of triglycerides in their livers. Postprandial lipoprotein lipase activity in epididymal adipose tissue was almost twice as high in the sucrose group as in the oil group. In the fasting state, but not in the fed state, plasma insulin levels correlated negatively with plasma triglycerides and positively with liver triglyceride content, whereas no relationship was observed between insulin and lipoprotein lipase activity in either fasted or fed animals. From the present findings, it appears that the sucrose-induced hypertriglyceridemia was not partly caused by decreased activity of lipoprotein lipase in white adipose tissue. Finally, this study suggests that the level of circulating insulin following intake of sucrose or corn oil may not determine per se the extent of stimulation of white adipose tissue lipoprotein lipase by these nutrients.

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