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Metabolic risk factors were assessed in 432 prebupertal children. Higher DHEAS concentration was associated with lower LDL cholesterol concentration.

Obesity is associated with disturbed lipid metabolism and low-grade inflammation in tissues. The aim of this study was to investigate the association between FA metabolism and adipose tissue (AT) inflammation in the Kuopio Obesity Surgery study. We investigated the association of surgery-induced weight loss and FA desaturase (FADS)1/2genotypes with serum and AT FA profile and with AT inflammation, measured as interleukin (IL)-1βand NFκB pathway gene expression, in order to find potential gene-environment interactions. We demonstrated an association between serum levels of saturated and polyunsaturated n-6 FAs, and estimated enzyme activities of FADS1/2genes with IL-1βexpression in AT both at baseline and at follow-up. Variation in the FADS1/2genes associated with IL-1βand NFκB pathway gene expression in SAT after weight reduction, but not at baseline. In addition, the FA composition in subcutaneous and visceral fat correlated with serum FAs, and the associations between serum PUFAs and estimated D6D enzyme activity with AT inflammation were also replicated with corresponding AT FAs and AT inflammation. We conclude that the polymorphism in FADS1/2genes associates with FA metabolism and AT inflammation, leading to an interaction between weight loss and FADS1/2genes in the regulation of AT inflammation.

Objective: To determine whether there are any changes in the fatty acid composition of serum triglycerides, cholesterol esters, and phospholipids induced by administration of orlistat three times a day compared with placebo as combined with a low-fat hypocaloric diet.Methods: After 4 weeks of placebo administration, 75 obese subjects were randomized to receive either one capsule (120 mg) of orlistat or placebo three times a day with meals for 1 year in conjunction with a nutritionally balanced hypocaloric diet. Food records were kept to estimat e the nutrient intake. The fatty acid composition of serum lipids were analyzed with gas chromatograph. The molar percentage proportions of fatty acids in serum lipid fractions were calculated.Results: Compared with placebo, there was a significant decrease in the proportion of linoleic acid in triglycerides, cholesterol esters, and phospholipids in the orlistat group, even after the effect of the decrease in the linoleic acid dietary intake (percent of energy), weight change, and gender were taken into account. However, the use of orlistat explained only 9% to 13% of the decrease in the proportion of linoleic acid in serum cholesterol esters, triglycerides, and phospholipids.Conclusion: The long-term treatment with orlistat may result in a small decline in the proportion of diet-derived fatty acids in serum lipid fractions when used in conjunction with low-fat diet.

The effects of a 14-week fish diet and exercise programme on lipid metabolism and platelet aggregation in healthy female students (n=99) were studied. The subjects were divided into four groups: a control group, a fish diet group (3.5 meals containing fish per week, 0.9 g n-3 fatty acids per day), an exercise group (at least three training sessions per week) and a combined fish diet and exercise group. The proportion of n-3 fatty acids increased at the expense of n-6 fatty acids in platelets and erythrocyte ghosts in the fish diet groups. Serum triglyceride concentrations tended to decrease in the fish diet and exercise groups and a significant decrease was found in the combined fish diet and exercise group (13%, P<0.05). No significant changes took place in the other serum lipid and apolipoprotein concentrations. Platelet production of thromboxane B2, plasma 6-keto-PGF1a concentrations and adenosine 5'diphosphate (ADP)-induced platelet aggregation also remained unchanged in all groups during the study. However, an inverse correlation was found between physical fitness (maximal oxygen uptake and maximal exercise intensity) and serum triglycerides, total cholesterol, low density lipoprotein cholesterol and platelet aggregation. This suggests that improved physical fitness is related to beneficial changes in serum lipid concentrations and to a decreased aggregation tendency of platelets. The responses of the female subjects to a fish diet were smaller when compared to earlier studies on male subjects. This suggests that there are sex differences in the efficiency of n-3 fatty acids in modifying lipid metabolism.

Sen, Chandan K., Mustafa Atalay, Jyrki Ågren, David E. Laaksonen, Sashwati Roy, and Osmo Hänninen. Fish oil and vitamin E supplementation in oxidative stress at rest and after physical exercise. J. Appl. Physiol.83(1): 189–195, 1997.—Fish oil supplementation and physical exercise may induce oxidative stress. We tested the effects of 8 wk of α-tocopherol (vitamin E) and fish oil (FO) supplementation on resting and exercise-induced oxidative stress. Rats (n= 80) were divided into groups supplemented with FO, FO and vitamin E (FOVE), soy oil (SO), and SO and vitamin E (SOVE), and for FOVE and SOVE they were divided into corresponding exercise groups (FOVE-Ex and SOVE-Ex). Lipid peroxidation [thiobarbituric acid-reacting substances (TBARS)] was 33% higher in FO compared with SO in the liver, but oxidative protein damage (carbonyl levels) remained similar in both liver and red gastrocnemius muscle (RG). Vitamin E supplementation, compared with FO and SO, markedly decreased liver and RG TBARS, but liver TBARS remained 32% higher in FOVE vs. SOVE. Vitamin E also markedly decreased liver and RG protein carbonyl levels, although levels in FOVE and SOVE were similar. Exercise increased liver and RG TBARS and RG protein carbonyl levels markedly, with similar levels in FOVE-Ex and SOVE-Ex. FO increased lipid peroxidation but not protein oxidation in a tissue-specific manner. Vitamin E markedly decreased lipid peroxidation and protein oxidation in both FOVE and SOVE, although liver lipid peroxidation remained higher in FOVE. Despite higher levels of hepatic lipid peroxidation at rest in FOVE compared with SOVE, liver appeared to be relatively less susceptible to exercise-induced oxidative stress in FOVE.

Dose responses over 12 weeks of meals containing fish on erythrocyte phospholipids were studied in male students. In all major glycerophospholipids the proportions of long chain n-3 fatty acids increased at the expense of n-6 fatty acids with 1.5 meals a week containing fish (0.5 g n-3 fatty acids per day). The rates and magnitudes of changes varied for individual phospholipids: faster but quantitatively smaller changes occurred in phosphatidylcholine than in phosphatidylethanolamine and phosphatidylserine. Fish diet and fish oil studies have usually been made using large doses over a short time. Our results show that similar effects might result from smaller amounts given over a longer time.