Long-chain N-3 Polyunsaturated Fatty Acids Research Articles

Long‐chain n−3 polyunsaturated fatty acid incorporation into human atrium following fish oil supplementation

Recent studies have demonstrated that long-chain n-3 PUFA (LCn-3PUFA) are beneficial in reducing the risk of cardiac arrhythmias. This study was conducted to determine the extent of incorporation of LCn-3PUFA into human atrium following supplementation with a fish oil concentrate high in LCn-3PUFA. Volunteers preparing for coronary bypass surgery were randomized either to the treatment group (n = 8), receiving 6 g/d of fish oil concentrate (4.4 g of LCn-3PUFA), or the placebo group (n = 9), receiving 6 g/d of olive oil for a minimum period of 6 wk. Blood samples were collected prior to commencement of treatment, and preoperatively before bypass surgery. Atrial biopsies were obtained during surgery. The plasma and atrium samples were analyzed by GC following trans-methylation to determine FA profile. Post-supplementation, the treatment group had significantly higher plasma levels of 20:5n-3, 22:5n-3, and 22:6n-3 than the placebo group. Analysis of the atrium total lipids revealed a significant increase in the proportion of 20:5n-3 following fish oil supplementation. There was no significant difference in the concentration of 22:5n-3 and 22:6n-3 in the atrium total lipids; however, an upward trend was observed in subjects receiving fish oil supplementation. In the phospholipid fraction of the atrium, both 20:5n-3 and 22:6n-3 increased, whereas 20:4n-6 levels decreased. This study demonstrates for the first time that short-term supplementation with fish oil concentrate results in significant incorporation of LCn-3PUFA with a concomitant depletion of the eicosanoid substrate (20:4n-6) in the human atrium.

Antioxidant enzymes and fatty acid status in erythrocytes of Down syndrome patients

The excess of genetic information in patients with Down's syndrome (DS) produces an increase in the catalytic activity of superoxide dismutase (SOD1), an antioxidant enzyme coded on chromosome 21. It has been suggested that an increase in oxidative stress in DS patients may cause adverse effects in the cell membranes through the oxidation of polyunsaturated fatty acids (PUFAs). The aim of this study was to evaluate the cellular antioxidant system by determining the catalytic activity of the SOD1, glutathione peroxidase (GPx), catalase (CAT), and glutathione reductase (GR) enzymes and the concentrations of alpha-tocopherol in red blood cells (RBCs) in a group of 72 DS patients. The profile of fatty acids in the phospholipids of RBC membranes was also evaluated. The activity of the erythrocyte antioxidant enzymes is significantly higher in the DS group than in the control group (SOD1, 635 +/- 70 U/g Hb vs 476 +/- 67 U/g Hb; CAT, 1843 +/- 250 U/g Hb vs 1482 +/- 250 U/g Hb; GPx, 23.2 +/- 5.3 U/g Hb vs 21.5 +/- 3.6 U/g Hb; and GR, 9.32 +/- 1.4 U/g Hb vs 6.9 +/- 1.3 U/g Hb, respectively). No differences were observed in RBC alpha-tocopherol concentrations between the two groups studied. Long-chain n6 PUFA (C20:3n6, C20:4n6) concentrations were increased in DS patients, suggesting enhanced delta-6-desaturase activity. The long-chain n3 PUFA (docosahexenoic acid) does not appear to be affected by increased oxidative stress, probably because of the existence of compensatory antioxidant mechanisms.

Clinical trial of deglycyrrhizinised liquorice in gastric ulcer.

Ninety-six patients with gastric ulcer were randomly allocated to treatment either with deglycyrrhizinised liquorice or placebo. After four weeks no differences were found between the treatment groups in the proportions with complete healing, whether assessed by gastroscopy or radiology, or in the percentage reduction in ulcer area, or in clinical improvement.