Klein-Platat C, Drai J, Oujaa M et al. Plasma fatty acid composition is associated with the metabolic syndrome and low-grade inflammation in overweight adolescents. Am J Clinical Nutrition, 2005; 82 (6), 1178-1184.

Background:
Together with adiposity, plasma fatty acid (FA) composition can modulate the development of the metabolic syndrome (MS).

Objective:
Our aim was to investigate the relations of FA composition in plasma phospholipids and cholesterol esters (CEs) with weight status, MS, and inflammation in adolescents.

Design:
Plasma FA composition was measured by gas-liquid chromatography in 120 (60 normal-weight and 60 overweight) 12-y-old adolescents. We also measured the presence of MS, insulin resistance with the homeostasis model assessment, and interleukin 6 and C-reactive protein concentrations in the adolescents.

Results:
MS was present in 25% of the overweight adolescents but in none of the normal-weight adolescents. Compared with overweight adolescents, normal-weight adolescents had lower saturated FAs (SFAs) in both phospholipids (P < 0.001) and CEs (P < 0.01) and higher docosahexaenoic acid in phospholipids (P < 0.001). In overweight subjects, FA composition was associated with MS features independent of body fat.

The odds ratios of MS for a 0.1 increase in the ratio of polyunsaturated FAs (PUFA) to SFAs (PUFA:SFA) were 0.91 in phospholipids (P = 0.03) and 0.90 in CEs (P = 0.06). In phospholipids, PUFA:SFA and linoleic acid were associated positively with HDL cholesterol (P < 0.01 for both). PUFA:SFA in phospholipids and CEs were associated inversely with interleukin 6 (P < 0.05 for both).

Eicosapentaenoic acid in phospholipids (P = 0.06) and CEs (P < 0.05) and linolenic acid in CEs (P < 0.05) were inversely related to C-reactive protein. These relations remained significant after adjustment for the waist-to-hip ratio. No significant relation between FA composition and the homeostasis model assessment was observed.

Conclusions:
Plasma FA composition is associated with weight status in healthy adolescents. High intake of long-chain PUFAs, especially n?3 PUFAs, may protect obese subjects against MS and low-grade inflammation as early as adolescence.

Mez-Shez N, Gonz?z V, et al. Fish Oil (n-3) Polyunsaturated Fatty Acids Beneficially Affect Biliary Cholesterol Nucleation Time in Obese Women Losing Weight. J. Nutr 2001;131:2300-2303

It has been reported that intake of (n-3) polyunsaturated fatty acids (PUFA) reduces the risk of coronary heart disease and decreases biliary cholesterol saturation in the bile of gallstone patients.

We investigated the effect of n-3 PUFA on cholesterol saturation index (CSI) and nucleation time (NT) in obese subjects who were losing weight. This was a double-blind, placebo-controlled clinical trial.

Obese women (n = 35) with a body mass index (BMI) 30 kg/m2, with no prior history of gallstones or cholecystectomy by ultrasound were first studied to ensure absence of stones or biliary sludge. The women were then assigned to a hypocaloric regimen [5.02 MJ (1200 kcal)/d] and to receive 1200 mg/d of ursodeoxycholic acid (UDCA), 11.3 g/d of (n-3) PUFA or a placebo for 6 wk. BMI, CSI and NT were recorded at baseline and at the end of the experimental period.

BMI decreased 5.75 ± 2.7%/mo (range, 1.5?12.42%/MO) during the experiment. The CSI did not change in any of the groups. Cholesterol NT decreased significantly in the UDCA and placebo groups, but not in the (n-3) PUFA group. None of the women had developed gallstones at 6 wk.

These results suggest that (n-3) PUFA maintain the CSI and NT in obese women during rapid weight loss, which probably results in the prevention of cholesterol gallstone formation.

Kim YJ, Kim HJ, No JK, et al. Anti-inflammatory action of dietary fish oil and calorie restriction. Life Sci. 2006;78(21):2523-2532.

Inflammation, inflammatory mediators, cyclooxygenase (COX)-2, and inducible nitric oxide (iNOS) are all influenced by age-related oxidative status.

To investigate the effect of dietary fish oil (FO) and calorie restriction (CR) on oxidative stress-related inflammatory status with age, (NZB/NZW) F1 (B/W) mice were fed for 4 and 9 months either ad libitum or calorie-restricted (60% of ad libitum intake) diets containing 5% corn oil or 5% FO.

We measured several key oxidative and inflammatory markers: TBARS, xanthine oxidase (XOD)-derived superoxide generation, and PGE(2) and LTB(4) production. Expressions of renal COX-1, COX-2, and iNOS mRNA were analyzed by RT-PCR; additionally, COX-2 protein was estimated by Western-blot method.

Results show that FO intake and CR individually and together suppressed age-related increases in lipid peroxidation and superoxide generation.

The inhibitory effects of dietary FO and CR were also found for iNOS expression, COX-2 expression, which subsequently led to the suppression of PGE(2) and LTB(4).

We conclude that the beneficial effects of FO feeding and CR are synergistic in ameliorating the age-related nephritis of B/W mice by suppressing COX-2 and iNOS, reactive species generation, and pro-inflammatory mediators.

PMID: 16438990

Allison Hill reported this morning, at the ISSFAL (International Society for the Study of Fatty Acids & Lipids) Congress in Cairns, Australia, new research findings on adjunct supplementation with fish oil in obese or overweight subjects (25 - 65 years old) assigned to a regular exercise regimen.

At entry, the 75 men and women, who also had two cardiovascular disease risk factors such as hypertension, elevated blood cholesterol or triglyceride, participated in a double blind trial of 12 weeks in duration.

The participants were assigned to either daily supplementation with vegetable oil with or without an exercise regimen or daily fish oil supplementation (providing 2 grams of DHA/EPA omega-3 fatty acids) with or without exercise. The moderate exercise program as assigned to half the subjects consisted of three running sessions per week for 45 minutes each at 75% of their age-predicted maximum heart rate.

Body compositions as increased by Dual Energy X-ray Absorptiometry revealed that the only group to exhibit a significant reduction in % body fat was that combining exercise with fish oil supplementation. This improvement appeared to reflect an enhanced fat oxidation during exercise.

The fish oil plus exercise regimen also gave a lessened surge in the heart rate rise with exercise which was attributed to a reduced vascular resistance and an improved blood flow in exercising muscles.

This novel research indicates the potential for fish oil supplementation to enhance the efficacy of exercise programs in overweight subjects.

Source: www.npicenter.com