Topography of very-long-chain-fatty-acid-activating activity in peroxisomes from rat liver.
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ABSTRACT:
SUBMITTER: Lageweg W
PROVIDER: S-EPMC1151142 | biostudies-other | 1991 May
REPOSITORIES: biostudies-other
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Project description:Background: Increased omega-3 (n-3) fatty acid consumption is reported to benefit patients with metabolic syndrome, possibly due to improved adipose tissue function.Objective: We tested the effects of high-dose, very-long-chain ?-3 fatty acids on adipose tissue inflammation and insulin regulation of lipolysis.Design: A double-blind, placebo-controlled study compared 6 mo of 3.9 g eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)/d (4.2 g total ?-3/d; n = 12) with a placebo (4.2 g oleate/d; n = 9) in insulin-resistant adults. Before and after treatment, the volunteers underwent adipose tissue biopsies to measure the total (CD68+), pro- (CD14+ = M1), and anti- (CD206+ = M2) inflammatory macrophages, crown-like structures, and senescent cells, as well as a 2-step pancreatic clamping with a [U-13C]palmitate infusion to determine the insulin concentration needed to suppress palmitate flux by 50% (IC50(palmitate)f).Results: In the ?-3 group, the EPA and DHA contributions to plasma free fatty acids increased (P = 0.0003 and P = 0.003, respectively), as did the EPA and DHA content in adipose tissue (P < 0.0001 and P < 0.0001, respectively). Despite increases in adipose and plasma EPA and DHA in the ?-3 group, there were no significant changes in the IC50(palmitate)f (19 ± 2 compared with 24 ± 3 ?IU/mL), adipose macrophages (total: 31 ± 2/100 adipocytes compared with 33 ± 2/100 adipocytes; CD14+: 13 ± 2/100 adipocytes compared with 14 ± 2/100 adipocytes; CD206+: 28 ± 2/100 adipocytes compared with 29 ± 3/100 adipocytes), crown-like structures (1 ± 0/10 images compared with 1 ± 0/10 images), or senescent cells (4% ± 1% compared with 4% ± 1%). There were no changes in these outcomes in the placebo group.Conclusions: Six months of high-dose ?-3 supplementation raised plasma and adipose ?-3 fatty acid concentrations but had no beneficial effects on adipose tissue lipolysis or inflammation in insulin-resistant adults. This trial was registered at clinicaltrials.gov as NCT01686568.
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