On the suppression of plasma nonesterified fatty acids by insulin during enhanced intravascular lipolysis in humans

André C. Carpentier, Frédérique Frisch, Denis Cyr, Philippe Généreux, Bruce W. Patterson, Robert Giguère, Jean Patrice Baillargeon

Research output: Contribution to journalArticle

47 Citations (Scopus)

Abstract

During the fasting state, insulin reduces nonesterified fatty acid (NEFA) appearance in the systemic circulation mostly by suppressing intracellular lipolysis in the adipose tissue. In the postprandial state, insulin may also control NEFA appearance through enhanced trapping into the adipose tissue of NEFA derived from intravascular triglyceride lipolysis. To determine the contribution of suppression of intracellular lipolysis in the modulation of plasma NEFA metabolism by insulin during enhanced intravascular triglyceride lipolysis, 10 healthy nonobese subjects underwent pancreatic clamps at fasting vs. high physiological insulin level with intravenous infusion of heparin plus Intralipid. Nicotinic acid was administered orally during the last 2 h of each 4-h clamp to inhibit intracellular lipolysis and assess insulin's effect on plasma NEFA metabolism independently of its effect on intracellular lipolysis. Stable isotope tracers of palmitate, acetate, and glycerol were used to assess plasma NEFA metabolism and total triglyceride lipolysis in each participant. The glycerol appearance rate was similar during fasting vs. high insulin level, but plasma NEFA levels were significantly lowered by insulin. Nicotinic acid significantly blunted the insulin-mediated suppression of plasma palmitate appearance and oxidation rates by ∼60 and ∼70%, respectively. In contrast, nicotinic acid did not affect the marked stimulation of palmitate clearance by insulin. Thus most of the insulin-mediated reduction of plasma NEFA appearance and oxidation can be explained by suppression of intracellular lipolysis during enhanced intravascular triglyceride lipolysis in healthy humans. Our results also suggest that insulin may affect plasma NEFA clearance independently of the suppression of intracellular lipolysis.

Original languageEnglish (US)
Pages (from-to)E849-E856
JournalAmerican Journal of Physiology - Endocrinology and Metabolism
Volume289
Issue number5 52-5
DOIs
StatePublished - Nov 1 2005

Fingerprint

Lipolysis
Nonesterified Fatty Acids
Insulin
Plasmas
Palmitates
Niacin
Triglycerides
Metabolism
Fasting
Clamping devices
Glycerol
Adipose Tissue
Tissue
Oxidation
Intravenous Infusions
Isotopes
Heparin
Healthy Volunteers
Acetates
Modulation

All Science Journal Classification (ASJC) codes

  • Endocrinology, Diabetes and Metabolism
  • Physiology
  • Physiology (medical)

Cite this

Carpentier, André C. ; Frisch, Frédérique ; Cyr, Denis ; Généreux, Philippe ; Patterson, Bruce W. ; Giguère, Robert ; Baillargeon, Jean Patrice. / On the suppression of plasma nonesterified fatty acids by insulin during enhanced intravascular lipolysis in humans. In: American Journal of Physiology - Endocrinology and Metabolism. 2005 ; Vol. 289, No. 5 52-5. pp. E849-E856.
@article{5422bdd6b0c24acb942d83bba2f2152d,
title = "On the suppression of plasma nonesterified fatty acids by insulin during enhanced intravascular lipolysis in humans",
abstract = "During the fasting state, insulin reduces nonesterified fatty acid (NEFA) appearance in the systemic circulation mostly by suppressing intracellular lipolysis in the adipose tissue. In the postprandial state, insulin may also control NEFA appearance through enhanced trapping into the adipose tissue of NEFA derived from intravascular triglyceride lipolysis. To determine the contribution of suppression of intracellular lipolysis in the modulation of plasma NEFA metabolism by insulin during enhanced intravascular triglyceride lipolysis, 10 healthy nonobese subjects underwent pancreatic clamps at fasting vs. high physiological insulin level with intravenous infusion of heparin plus Intralipid. Nicotinic acid was administered orally during the last 2 h of each 4-h clamp to inhibit intracellular lipolysis and assess insulin's effect on plasma NEFA metabolism independently of its effect on intracellular lipolysis. Stable isotope tracers of palmitate, acetate, and glycerol were used to assess plasma NEFA metabolism and total triglyceride lipolysis in each participant. The glycerol appearance rate was similar during fasting vs. high insulin level, but plasma NEFA levels were significantly lowered by insulin. Nicotinic acid significantly blunted the insulin-mediated suppression of plasma palmitate appearance and oxidation rates by ∼60 and ∼70{\%}, respectively. In contrast, nicotinic acid did not affect the marked stimulation of palmitate clearance by insulin. Thus most of the insulin-mediated reduction of plasma NEFA appearance and oxidation can be explained by suppression of intracellular lipolysis during enhanced intravascular triglyceride lipolysis in healthy humans. Our results also suggest that insulin may affect plasma NEFA clearance independently of the suppression of intracellular lipolysis.",
author = "Carpentier, {Andr{\'e} C.} and Fr{\'e}d{\'e}rique Frisch and Denis Cyr and Philippe G{\'e}n{\'e}reux and Patterson, {Bruce W.} and Robert Gigu{\`e}re and Baillargeon, {Jean Patrice}",
year = "2005",
month = "11",
day = "1",
doi = "10.1152/ajpendo.00073.2005",
language = "English (US)",
volume = "289",
pages = "E849--E856",
journal = "American Journal of Physiology - Endocrinology and Metabolism",
issn = "0193-1849",
publisher = "American Physiological Society",
number = "5 52-5",

}

On the suppression of plasma nonesterified fatty acids by insulin during enhanced intravascular lipolysis in humans. / Carpentier, André C.; Frisch, Frédérique; Cyr, Denis; Généreux, Philippe; Patterson, Bruce W.; Giguère, Robert; Baillargeon, Jean Patrice.

In: American Journal of Physiology - Endocrinology and Metabolism, Vol. 289, No. 5 52-5, 01.11.2005, p. E849-E856.

Research output: Contribution to journalArticle

TY - JOUR

T1 - On the suppression of plasma nonesterified fatty acids by insulin during enhanced intravascular lipolysis in humans

AU - Carpentier, André C.

AU - Frisch, Frédérique

AU - Cyr, Denis

AU - Généreux, Philippe

AU - Patterson, Bruce W.

AU - Giguère, Robert

AU - Baillargeon, Jean Patrice

PY - 2005/11/1

Y1 - 2005/11/1

N2 - During the fasting state, insulin reduces nonesterified fatty acid (NEFA) appearance in the systemic circulation mostly by suppressing intracellular lipolysis in the adipose tissue. In the postprandial state, insulin may also control NEFA appearance through enhanced trapping into the adipose tissue of NEFA derived from intravascular triglyceride lipolysis. To determine the contribution of suppression of intracellular lipolysis in the modulation of plasma NEFA metabolism by insulin during enhanced intravascular triglyceride lipolysis, 10 healthy nonobese subjects underwent pancreatic clamps at fasting vs. high physiological insulin level with intravenous infusion of heparin plus Intralipid. Nicotinic acid was administered orally during the last 2 h of each 4-h clamp to inhibit intracellular lipolysis and assess insulin's effect on plasma NEFA metabolism independently of its effect on intracellular lipolysis. Stable isotope tracers of palmitate, acetate, and glycerol were used to assess plasma NEFA metabolism and total triglyceride lipolysis in each participant. The glycerol appearance rate was similar during fasting vs. high insulin level, but plasma NEFA levels were significantly lowered by insulin. Nicotinic acid significantly blunted the insulin-mediated suppression of plasma palmitate appearance and oxidation rates by ∼60 and ∼70%, respectively. In contrast, nicotinic acid did not affect the marked stimulation of palmitate clearance by insulin. Thus most of the insulin-mediated reduction of plasma NEFA appearance and oxidation can be explained by suppression of intracellular lipolysis during enhanced intravascular triglyceride lipolysis in healthy humans. Our results also suggest that insulin may affect plasma NEFA clearance independently of the suppression of intracellular lipolysis.

AB - During the fasting state, insulin reduces nonesterified fatty acid (NEFA) appearance in the systemic circulation mostly by suppressing intracellular lipolysis in the adipose tissue. In the postprandial state, insulin may also control NEFA appearance through enhanced trapping into the adipose tissue of NEFA derived from intravascular triglyceride lipolysis. To determine the contribution of suppression of intracellular lipolysis in the modulation of plasma NEFA metabolism by insulin during enhanced intravascular triglyceride lipolysis, 10 healthy nonobese subjects underwent pancreatic clamps at fasting vs. high physiological insulin level with intravenous infusion of heparin plus Intralipid. Nicotinic acid was administered orally during the last 2 h of each 4-h clamp to inhibit intracellular lipolysis and assess insulin's effect on plasma NEFA metabolism independently of its effect on intracellular lipolysis. Stable isotope tracers of palmitate, acetate, and glycerol were used to assess plasma NEFA metabolism and total triglyceride lipolysis in each participant. The glycerol appearance rate was similar during fasting vs. high insulin level, but plasma NEFA levels were significantly lowered by insulin. Nicotinic acid significantly blunted the insulin-mediated suppression of plasma palmitate appearance and oxidation rates by ∼60 and ∼70%, respectively. In contrast, nicotinic acid did not affect the marked stimulation of palmitate clearance by insulin. Thus most of the insulin-mediated reduction of plasma NEFA appearance and oxidation can be explained by suppression of intracellular lipolysis during enhanced intravascular triglyceride lipolysis in healthy humans. Our results also suggest that insulin may affect plasma NEFA clearance independently of the suppression of intracellular lipolysis.

UR - http://www.scopus.com/inward/record.url?scp=27144472377&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=27144472377&partnerID=8YFLogxK

U2 - 10.1152/ajpendo.00073.2005

DO - 10.1152/ajpendo.00073.2005

M3 - Article

C2 - 15972273

AN - SCOPUS:27144472377

VL - 289

SP - E849-E856

JO - American Journal of Physiology - Endocrinology and Metabolism

JF - American Journal of Physiology - Endocrinology and Metabolism

SN - 0193-1849

IS - 5 52-5

ER -