Effects of Insulin on Human Adipose Tissue Metabolism in Vivo

1989 ◽  
Vol 77 (6) ◽  
pp. 663-670 ◽  
Author(s):  
S. W. Coppack ◽  
K. N. Frayn ◽  
S. M. Humphreys ◽  
H. Dhar ◽  
T. D. R. Hockaday
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Oxygen Uptake ◽  
Carbon Balance ◽  
Insulin Infusion ◽  
Human Adipose Tissue ◽  
Metabolic Effects ◽  
Fasting State ◽  
Esterified Fatty Acids ◽  
Glucose Ingestion

1. The metabolic effects of insulin on human adipose tissue were studied by combining the euglycaemic clamp technique with measurement of arteriovenous differences across the subcutaneous adipose tissue of the anterior abdominal wall 2. Eight normal subjects were studied after an overnight fast, and for 120 min during infusion of insulin (mean arterialized plasma insulin 50–55 m-units/l) 3. During the insulin infusion, the arterialized and abdominal venous levels of both non-esterified fatty acids and glycerol fell, and the arteriovenous differences for the release of these substances narrowed. The fractional rate of re-esterification of fatty acids was around 20% in the fasting state and increased to almost 100% during hyper-insulinaemia 4. In the fasting state the uptake of glucose and 3-hydroxybutyrate by adipose tissue could account for only 20% of the oxygen uptake. During insulin infusion, adipose tissue glucose uptake increased and could account for more than 100% of oxygen uptake, implying storage of glucose 5. Net balances of different substrates across adipose tissue were examined by calculating fluxes in terms of μg-atoms of carbon. In the fasting state adipose tissue was in marked negative carbon balance (because of the export of non-esterified fatty acids); during insulin infusion it just reached ‘carbon balance’. These results were in contrast to those from a previous study of glucose ingestion, in which the adipose tissue showed marked positive carbon balance (net substrate deposition).

Postprandial Substrate Deposition in Human Forearm and Adipose Tissues in Vivo

1990 ◽  
Vol 79 (4) ◽  
pp. 339-348 ◽  
Author(s):  
S. W. Coppack ◽  
R. M. Fisher ◽  
G. F. Gibbons ◽  
S. M. Humphreys ◽  
M. J. McDonough ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Fatty Acids ◽  
Adipose Tissue ◽  
Carbon Balance ◽  
Plasma Concentrations ◽  
Normal Subjects ◽  
Esterified Fatty Acids ◽  
Positive Balance ◽  
A Minor

1. Substrate movements in forearm muscle and subcutaneous adipose tissue were studied, by measurement of arteriovenous differences and blood flow, in seven normal subjects after an overnight fast and then for 6 h after ingestion of a mixed meal. Overall substrate balances were examined in terms of the flux of gram-atoms of carbon. 2. As found previously, the forearm was approximately in carbon balance (import equal to export) after the overnight fast, whereas adipose tissue was a net exporter of carbon, mainly in the form of non-esterified fatty acids. 3. After the meal, arterialized plasma concentrations of glucose and lactate rose sharply (peak at 60 min), whereas those of non-esterified fatty acids and glycerol fell (nadir at 60–120 min). Plasma triacylglycerol concentrations rose slowly to peak at 240 min; much of this rise was accounted for by a rise in the chylomicron fraction. 4. Both tissues took up glucose at an increased rate after the meal. Release of non-esterified fatty acids and glycerol from adipose tissue was suppressed. Clearance of triacylglycerol by both tissues increased after the meal, but was more marked in adipose tissue, where the fractional extraction of chylomicron-triacylglycerol reached 44% at 240 min. 5. The forearm rapidly became a considerable net importer of carbon, and remained so until 6 h after the meal when it was again in approximate carbon balance. Glucose uptake dominated the forearm carbon balance. Adipose tissue was a net importer of carbon from 30 min until 5 h after the meal and then reverted to net export. Clearance of triacylglycerol carbon made the largest contribution to this positive balance, but towards the end of the study this was increasingly counterbalanced by simultaneous non-esterified fatty acid release. 6. Skeletal muscle plays a major role, and adipose tissue a minor one, in the disposal of ingested carbohydrate; adipose tissue plays a major role and skeletal muscle a minor one in clearance of dietary-derived triacylglycerol. The role of adipose tissue lipoprotein lipase is not, however, simply the uptake of triacylglycerol for storage within the tissue; rather, it appears to play a central role in the distribution of dietary-derived lipid energy.

Effect of Propolis-Supplemented Diet on Body Composition and Endocrine Function of Adipose Tissue

2020 ◽  
Vol 19 (2) ◽  
pp. 217-221
Author(s):  
Maria Jesús Lisbona-González ◽  
Candela Reyes-Botella ◽  
Esther Muñoz-Soto ◽  
Maria Victoria Olmedo-Gaya, ◽  
Jorge Moreno-Fernandez ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Body Composition ◽  
Adipose Tissue ◽  
Endocrine Function ◽  
Control Group ◽  
Albino Rats ◽  
Standard Diet ◽  
Reduced Body ◽  
Esterified Fatty Acids ◽  
Wistar Albino Rats

Adipose tissue is an endocrine organ and has central role in interaction with other organs or tissues while propolis can induce lipolysis. Therefore, the aim of this study is to provide detailed information about adipose tissue homeostasis modifications and body composition during propolis supplement consumption. Twenty male Wistar albino rats (8 weeks) were divided into two groups of 10 animals each and fed for 90 days with two different types of diets: standard for the control group (diet C) and standard diet + 2% propolis (diet P). Thyroid hormones did not show differences, while ghrelin and adiponectin decreased in the group that was fed propolis. Insulin, leptin, and non-esterified fatty acids also increased along with reduced body weight and fat, in addition to increased lean mass when propolis was in the diet. We conclude that propolis could decrease ghrelin and adiponectin but increase non-esterified fatty acids and insulin secretion, which improves body composition.

Effects of growth hormone-releasing factors and cottonseed meal on hormones and metabolites in plasma from lambs fed lucerne chaff ad libitum

1994 ◽  
Vol 45 (6) ◽  
pp. 1125 ◽  
Author(s):  
RD Sainz ◽  
BJ Hosking ◽  
FJ Hart ◽  
GSG Spencer
Keyword(s):  
Fatty Acids ◽  
Growth Hormone ◽  
Growth Factor ◽  
Cottonseed Meal ◽  
Metabolic Effects ◽  
Insulin Like Growth Factor ◽  
Plasma Urea ◽  
Blood Samples ◽  
Esterified Fatty Acids ◽  
Ad Libitum

This study was part of an experiment on the effects of cottonseed meal (CSM) and growth hormone-releasing factor (GRF) on growth in lambs fed lucerne chaff. Forty-eight crossbred lambs were fed lucerne chaff ad libitum, alone or with a cottonseed meal supplement (CSM; 300 g/day). Eight lambs from each group were injected twice daily with recombinant or synthetic GRF (rGRF and sGRF respectively; 30 8g per kg body weight/day) or excipient only for 28 or 30 days. Jugular blood samples were obtained on days 0, 7, 14, 21 and 28. On day 29, blood samples were taken from selected lambs (n = 2/group) at 0, 20, 40, 60, 80, 100, 120, 160 and 240 min after injection. Supplementation of lucerne chaff with CSM generally increased glucose and urea concentrations in plasma, reflecting improved energy and protein status. However, concentrations of growth hormone, insulin-like growth factor-1 and insulin were unaffected by CSM, as were plasma proteins, triacylglycerols and non-esterified fatty acids. Injection of rGRF and sGRF stimulated secretion of growth hormone (GH), insulin-like growth factor-1 (IGF-1) and insulin. Peak GH concentrations (20 min) following injection of GRF appeared to be higher in lambs fed CSM than in those receiving lucerne chaff alone. In contrast, maximal concentrations of IGF-1 were seen after 14 days of treatment. These changes were accompanied by increased plasma glucose, with no changes in triacylglycerols, non-esterified fatty acids and protein. Plasma urea was reduced by GRF, indicating that amino acids were diverted away from catabolism towards protein synthesis. These two sources of GRF were very similar in their endocrine and metabolic effects. This confirms similar observations regarding their effects on growth performance and carcass composition.

scholarly journals The role of dietary fatty acids for early human adipose tissue growth

2013 ◽  
Vol 98 (2) ◽  
pp. 549S-555S ◽  
Author(s):  
Hans Hauner ◽  
Stefanie Brunner ◽  
Ulrike Amann-Gassner
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Human Adipose Tissue ◽  
Tissue Growth ◽  
Dietary Fatty Acids ◽  
Early Human

scholarly journals Acute exposure to long-chain fatty acids impairs α2-adrenergic receptor-mediated antilipolysis in human adipose tissue

2007 ◽  
Vol 48 (10) ◽  
pp. 2236-2246 ◽  
Author(s):  
Jan Polak ◽  
Cédric Moro ◽  
David Bessière ◽  
Jindra Hejnova ◽  
Marie A. Marquès ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Adrenergic Receptor ◽  
Human Adipose Tissue ◽  
Acute Exposure ◽  
Long Chain Fatty Acids ◽  
Long Chain ◽  
Chain Fatty Acids

No effect of acute normobaric hypoxia on plasma triglyceride levels in fasting healthy men

2018 ◽  
Vol 43 (7) ◽  
pp. 727-732 ◽  
Author(s):  
Bimit Mahat ◽  
Étienne Chassé ◽  
Clare Lindon ◽  
Jean-François Mauger ◽  
Pascal Imbeault
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Acute Hypoxia ◽  
Density Lipoprotein ◽  
Ambient Air ◽  
Normobaric Hypoxia ◽  
Fasting State ◽  
Nonesterified Fatty Acids ◽  
Healthy Men ◽  
Adipose Tissue Lipolysis

Circulating fatty acids are a major systemic energy source in the fasting state as well as a determinant of hepatic triglycerides (TG)-rich very-low-density lipoprotein production. Upon acute hypoxia, sympathetic arousal induces adipose tissue lipolysis, resulting in an increase in circulating nonesterified fatty acids (NEFA). Animal studies suggest that TG clearance may also be strongly reduced under hypoxia, though this effect has been shown to be dependent on temperature. Whether the hypoxia-induced rise in blood fatty acid concentrations affects fasting TG levels in humans under thermoneutral conditions remains unknown. TG, NEFA, and glycerol levels were measured in fasted healthy young men (n = 10) exposed for 6 h to either normoxia (ambient air) or acute hypoxia (fraction of inspired oxygen = 0.12) in a randomized, crossover design. Participants were casually clothed and rested in front of a fan in an environmental chamber maintained at 28 °C during each trial. Under hypoxia, a significantly greater increase in NEFA occurred (condition × time interaction, p = 0.049) and glycerol levels tended to be higher (condition × time, p = 0.104), suggesting an increase in adipose tissue lipolysis. However, plasma TG levels did not change over time and did not differ between the normoxia and hypoxia conditions. In conclusion, acute exposure to normobaric hypoxia under thermoneutral condition in healthy men during fasting state increased lipolysis without affecting circulating TG.

The role of free fatty acids in the regulation of lipolysis by human adipose tissue cells

Metabolism ◽  
1978 ◽  
Vol 27 (12) ◽  
pp. 1755-1762 ◽  
Author(s):  
Thomas W. Burns ◽  
Paul E. Langley ◽  
Boyd E. Terry ◽  
G.Alan Robinson
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Free Fatty Acids ◽  
Human Adipose Tissue ◽  
Tissue Cells ◽  
Adipose Tissue Cells

Human adipose tissue is a putative direct target of daytime orexin with favorable metabolic effects: A cross‐sectional study

Obesity ◽  
2021 ◽  
Author(s):  
Nir Goldstein ◽  
Hiroshi Tsuneki ◽  
Nikhil Bhandarkar ◽  
Eleonora Aimaretti ◽  
Yulia Haim ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Human Adipose Tissue ◽  
Cross Sectional Study ◽  
Metabolic Effects ◽  
Sectional Study ◽  
Cross Sectional ◽  
Direct Target

scholarly journals Release of Non-Esterified Fatty Acids from Adipose Tissue in Normal and Diabetic Rats

Nature ◽  
1959 ◽  
Vol 184 (4693) ◽  
pp. 1147-1147 ◽  
Author(s):  
J. WENKEOVÁ ◽  
J. PÁV
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Diabetic Rats ◽  
Esterified Fatty Acids

scholarly journals Supplementary dietary calcium stimulates faecal fat and bile acid excretion, but does not protect against obesity and insulin resistance in C57BL/6J mice

2010 ◽  
Vol 105 (7) ◽  
pp. 1005-1011 ◽  
Author(s):  
Nicole J. W. de Wit ◽  
Hanneke Bosch-Vermeulen ◽  
Els Oosterink ◽  
Michael Müller ◽  
Roelof van der Meer
Keyword(s):  
Gene Expression ◽  
Insulin Resistance ◽  
Fatty Acids ◽  
Adipose Tissue ◽  
Protective Effect ◽  
Bile Acids ◽  
Early Gene ◽  
Metabolic Effects ◽  
Faecal Excretion ◽  
The Metabolic Syndrome

There is increased interest in the potential protective role of dietary Ca in the development of metabolic disorders related to the metabolic syndrome. Ca-induced intestinal precipitation of fatty acids and bile acids as well as systemic metabolic effects of Ca on adipose tissue is proposed to play a causal role. In this experiment, we have studied all these aspects to validate the suggested protective effect of Ca supplementation, independent of other dietary changes, on the development of diet-induced obesity and insulin resistance. In our diet intervention study, C57BL/6J mice were fed high-fat diets differing in Ca concentrations (50 v. 150 mmol/kg). Faecal excretion analyses showed an elevated precipitation of intestinal fatty acids (2·3-fold; P < 0·01) and bile acids (2-fold; P < 0·01) on the high-Ca diet. However, this only led to a slight reduction in fat absorption (from 98 to 95 %; P < 0·01), mainly in the distal small intestine as indicated by gene expression changes. We found no effect on body-weight gain. Lipolysis and lipogenesis-related parameters in adipose tissue also showed no significant changes on the high-Ca diet, indicating no systemic effects of dietary Ca on adiposity. Furthermore, early gene expression changes of intestinal signalling molecules predicted no protective effect of dietary Ca on the development of insulin resistance, which was confirmed by equal values for insulin sensitivity on both diets. Taken together, our data do not support the proposed protective effect of dietary Ca on the development of obesity and/or insulin resistance, despite a significant increase in faecal excretion of fatty acids and bile acids.

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