COL - Impact Of Omega-3 On Cardiovascular Disease In Type 2 Diabetes

Hartweg J, Farmer AJ, Holman RR, Neil A.

Source

Division of Public Health and Primary Healthcare, University of Oxford, Oxford, UK. Janine.Hartweg@green.ox.ac.uk

Abstract

PURPOSE OF REVIEW:

Hypothesis-generating systematic review of the impact of marine-derived omega-3 polyunsaturated fatty acids (PUFAs) on lipid, glycemic and hematological risk factors in type 2 diabetes using pooled data from randomized controlled trials searched up to 20 September 2008.

RECENT FINDINGS:

Seven new trials in 2007 and 2008 were identified from 206 abstracts to give a total of 24 trials between 1966 and 2008 involving 1533 participants that could be pooled. The mean omega-3 PUFAs dose and duration of treatment in the new trials was 2.4 g/day and 24 weeks, respectively. Compared with placebo, omega-3 PUFAs supplementation decreased triglycerides by 7% (mean -0.17 mmol/l, 24 trials, 1530 participants), fibrinogen by 10% (mean -0.96 micromol/l, three trials, 159 participants), ADP platelet aggregation to ADP by 22% (mean -10.30%, two trials, 64 participants) and to collagen by 21% (mean -10.55%, two trials, 64 participants), with an LDL-cholesterol increase of 3% (mean 0.08 mmol/l, 21 trials, 1104 participants). None of the following risk factors appeared to be beneficially influenced: HDL-cholesterol, LDL particle size, glycemia, insulinemia, inflammatory biomarkers, blood pressure. However for some of these risk factors (such as inflammatory biomarkers) the number of trial patients was small Higher doses of omega-3 PUFAs (>or=2 g/day) may have greater triglyceride lowering effects.

SUMMARY:

This systematic review and meta-analysis confirms the triglyceride lowering effects of omega-3 PUFAs, demonstrates potential dose-response effects and shows improvements in thrombogenesis. Omega-3 PUFAs raise LDL levels without concomitant changes in lipid particle size. Changes seen in conventional risk factors are insufficient to explain the cardiovascular disease risk reductions suggested to occur with omega-3 PUFAs.

PMID:

 

19133409

 

[PubMed - indexed for MEDLINE]

NH – Omega-3 FA in Glucose Metabolism and Insulin Sensitivity

Martín de Santa Olalla L, Sánchez Muniz FJ, Vaquero MP.

Source

Department of Metabolism and Nutrition, Instituto del Frío, Instituto de Ciencia y Tecnología de Alimentos y Nutrición (ICTAN), Spanish Nacional Research Council (CSIC), Madrid, Spain.

Abstract

Polyunsaturated fatty acids (PUFA) of the n-3 series are essential for normal growth and development. The health effects of these fatty acids include reduction of cardiovascular risk due to antiarrhythmic, antiinflammatory, anti-thrombotic and lipid lowering actions. An increase in unsaturation of the muscle membrane fatty acids is associated with improved insulin sensitivity. Higher proportion of n-3 fatty acids may have beneficial roles, such as antiobesity effects and protection against the metabolic syndrome and type 2 diabetes mellitus through a number of metabolic effects. However, controversy exists on the different effects of n-6 and n-3 polyunsaturated fatty acids as well as on the interacting effect of dietary saturated and monounsaturated fat. In addition, some adverse effects have been described concerning the use of fish oil supplements containing high doses of n-3 fatty acids. Several studies show Eskimos diabetes risk, while results of nutritional interventions on the influence of consuming diets rich in oily fish or other food rich in n-3 fatty acids is very limited. This article reviews the possible mechanisms through which n-3 PUFA are involved in glucose level control and insulin sensitivity. Intervention and epidemiological studies together with recent findings on the nutrigenomic field related with this subject are also briefly reviewed.

PMID:

 

19593479

 

[PubMed - indexed for MEDLINE]

Athero - Fish Oil Yields Beneficial Cardiovascular And Metabolic Health Effects

Rizza S, Tesauro M, Cardillo C, Galli A, Iantorno M, Gigli F, Sbraccia P, Federici M, Quon MJ, Lauro D.

Source

Center for Atherosclerosis Policlinico Tor Vergata University Hospital, Internal Medicine Department, Rome, Italy. stefano.rizza@tin.it

Abstract

OBJECTIVE:

Offspring of patients with type 2 diabetes (OPDs) exhibits endothelial dysfunction (ED) associated with a chronic inflammatory state. N-3 polyunsaturated fatty acids (n-3 PUFA) may have antioxidant and anti-inflammatory properties that are beneficial for cardiovascular and metabolic health. Therefore, in the present study, we tested the hypothesis that dietary supplementation with fish oil rich in n-3 PUFA may improve ED in otherwise healthy OPDs.

METHODS AND DESIGN:

A double-blind, placebo-controlled trial was conducted with 50 OPDs. Participants were randomized to treatment with either placebo or n-3 PUFA (2g/day) for 12 weeks. Before and after treatment we evaluated endothelial function (using flow-mediated dilation (FMD) of the brachial artery), circulating inflammatory markers (adiponectin, TNF-alpha, and high sensitivity-CRP), and insulin resistance (QUICKI).

RESULTS:

No significant changes were observed in study outcomes in subjects treated with placebo. By contrast, when compared with baseline values, subjects treated with n-3 PUFA had significant improvement in FMD (9.1+/-5.8% vs. 11.7+/-4.4%, p=0.02) that was accompanied by decreased plasma triglycerides (117+/-73mg/dl vs. 86+/-44mg/dl, p=0.001) and TNF-alpha levels (8.9+/-2.3pg/ml vs. 6.8+/-2.7pg/ml, p=0.001), and a trend towards increased plasma adiponectin levels (7.8+/-4.5microg/ml vs. 9.5+/-5.1microg/ml, p=0.09). When data were analyzed by multiple regression analysis, decreased TNF-alpha after treatment with n-3 PUFA predicted increased FMD.

CONCLUSION:

Dietary supplementation with n-3 PUFA significantly improved endothelial function and reduced pro-inflammatory markers in OPDs. Thus, fish oil consumption may have beneficial cardiovascular and metabolic health effects in otherwise healthy subjects predisposed to diabetes and its vascular complications.

PMID:

 

19394939

 

[PubMed - indexed for MEDLINE]

NMCD - Consumption Of Omega-3 FAs Decrease Homocysteine Levels In Diabetic Patients

Pooya Sh, Jalali MD, Jazayery AD, Saedisomeolia A, Eshraghian MR, Toorang F.

Source

Department of Nutrition and Biochemistry, School of Health, Tehran University of Medical Sciences, Tehran, Iran.

Abstract

BACKGROUND AND AIMS:

Cardiovascular diseases are the major cause of mortality among diabetic patients. The concentration of malondialdehyde (MDA) and homocysteine is believed to play a role in cardiovascular diseases. Omega-3 fatty acid supplementation could be effective in some diabetes complications and in the control of the glycemic index. However, it may increase lipid peroxidation. The objective of this study was to determine the effect of omega-3 fatty acids on the concentration of homocysteine and MDA in diabetic patients.

METHODS AND RESULTS:

A randomized double-blind, placebo-controlled clinical trial was conducted on 81 patients with type 2 diabetes. The patients were randomly assigned to either the treatment or control groups. Each subject received three capsules of omega-3 fatty acids or a placebo every day for a period of 2months. The two groups were similar in terms of body mass index and food intake. At the beginning of the study and after 2months of supplementation their levels of HbA(1)c, homocysteine, MDA, C-reactive protein (CRP), total cholesterol, LDL-cholesterol and fasting blood sugar (FBS) were determined. Due to omega-3 fatty acid supplementation, homocysteine was changed significantly in both treatment and control groups up to -3.10mumol/L and 0.10mumol/L respectively, and HbA(1)c decreased by 0.75% in the treatment group and increased by 0.26% in the control group. However, the changes in fasting blood sugar (FBS), malondialdehyde (MDA), C-reactive protein (CRP), total cholesterol and LDL-cholesterol levels were not significant.

CONCLUSION:

The consumption of omega-3 fatty acid supplements (3g/day) for 2months decreases the levels of homocysteine in diabetic patients with no change in FBS, MDA and CRP levels.

PMID:

 

19540739

 

[PubMed - indexed for MEDLINE]

FASEB - Resolvins and Protectins Benefit Obesity-Induced Insulin Resistance

1. Ana González-Périz ^* , 
2. Raquel Horrillo ^* , 
3. Natàlia Ferré ^* ,
4. Karsten Gronert ^‡ , 
5. Baiyan Dong ^‡ , 
6. Eva Morán-Salvador ^* , 
7. Esther Titos ^*, 
8. Marcos Martínez-Clemente ^* , 
9. Marta López-Parra ^* , 
10. Vicente Arroyo ^†and 
11. Joan Clària ^*

1. ^*Department of Biochemistry and Molecular Genetics and
3. ^†Liver Unit, Hospital Clínic, Institut d’Investigacions Biomèdiques August Pi I Sunyer, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, University of Barcelona, Barcelona, Spain; and
5. ^‡Center for Eye Disease and Development, School of Optometry, University of California, Berkeley, California, USA

1. ¹Correspondence: Department of Biochemistry and Molecular Genetics, Hospital Clínic, Villarroel 170, Barcelona 08036, Spain. E-mail: jclaria@clinic.ub.es

 

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Abstract

Omega-3-polyunsaturated fatty acids (ω-3-PUFAs) have well-documented protective effects that are attributed not only to eicosanoid inhibition but also to the formation of novel biologically active lipid mediators (i.e., resolvins and protectins). In this study, we examined their effects on ob/ob mice, an obesity model of insulin resistance and fatty liver disease. Dietary intake of ω-3-PUFAs had insulin-sensitizing actions in adipose tissue and liver and improved insulin tolerance in obese mice. Genes involved in insulin sensitivity (PPARγ), glucose transport (GLUT-2/GLUT-4), and insulin receptor signaling (IRS-1/IRS-2) were up-regulated by ω-3-PUFAs. Moreover, ω-3-PUFAs increased adiponectin, an anti-inflammatory and insulin-sensitizing adipokine, and induced AMPK phosphorylation, a fuel-sensing enzyme and a gatekeeper of the energy balance. Concomitantly, hepatic steatosis was alleviated by ω-3-PUFAs. A lipidomic analysis with liquid chromatography/mass spectrometry/mass spectrometry revealed that ω-3-PUFAs inhibited the formation of ω-6-PUFA-derived eicosanoids, while triggering the formation of ω-3-PUFA-derived resolvins and protectins. Moreover, representative members of these lipid mediators, namely resolvin E1 and protectin D1, mimicked the insulin-sensitizing and antisteatotic effects of ω-3-PUFAs and induced adiponectin expression to a similar extent that of rosiglitazone, a member of the thiazolidinedione family of antidiabetic drugs. Taken together, these findings uncover beneficial actions of ω-3-PUFAs and their bioactive lipid autacoids in preventing obesity-induced insulin resistance and hepatic steatosis.—González-Périz, A., Horrillo, R., Ferré, N., Gronert, K., Dong, B., Morán-Salvador, E., Titos, E., Martínez-Clemente, M., López-Parra, M., Arroyo, V., Clària, J. Obesity-induced insulin resistance and hepatic steatosis are alleviated by ω-3 fatty acids: a role for resolvins and protectins.