N-3 fatty acid supplementation decreases plasma homocysteine in diabetic dyslipidemia treated with statin–fibrate combination

Epigenetic Regulation by microRNAs in Hyperhomocysteinemia-Accelerated Atherosclerosis

Increased serum levels of homocysteine (Hcy) is a risk factor for cardiovascular disease and is specifically linked to various diseases of the vasculature such as atherosclerosis. However, the precise mechanisms by which Hcy contributes to this condition remain elusive. During the development of atherosclerosis, epigenetic modifications influence gene expression. As such, epigenetic modifications are an adaptive response to endogenous and exogenous factors that lead to altered gene expression by methylation and acetylation reactions of different substrates and the action of noncoding RNA including microRNAs (miRNAs). Epigenetic remodeling modulates cell biology in both physiological and physiopathological conditions. DNA and histone modification have been identified to have a crucial role in the progression of atherosclerosis. However, the potential role of miRNAs in hyperHcy (HHcy)-related atherosclerosis disease remains poorly explored and might be essential as well. There is no review available yet summarizing the contribution of miRNAs to hyperhomocystein-mediated atherogenicity or their potential as therapeutic targets even though their important role has been described in numerous studies. Specifically, downregulation of miR-143 or miR-125b has been shown to regulate VSCMs proliferation in vitro. In preclinical studies, downregulation of miR-92 or miR195-3p has been shown to increase the accumulation of cholesterol in foam cells and increase macrophage inflammation and atherosclerotic plaque formation, respectively. Another preclinical study found that there is a reciprocal regulation between miR-148a/152 and DNMT1 in Hcy-accelerated atherosclerosis. Interestingly, a couple of studies have shown that miR-143 or miR-217 may be used as potential biomarkers in patients with HHcy that may develop atherosclerosis. Moreover, the current review will also update current knowledge on miRNA-based therapies, their challenges, and approaches to deal with Hcy-induced atherosclerosis.

Impact of Omega-3 supplementation on homocysteine levels in humans: A systematic review and meta-regression analysis of randomized controlled trials

AIMS

Although some evidence suggests that omega-3 polyunsaturated fatty acids (PUFAs) supplementation influences enzymes involved in forming homocysteine (Hcy) and improving hyperhomocysteinemia, these findings are still contradictory in humans. The aim of this systematic and meta-analysis study was to investigate the effects of omega-3 supplementation on Hcy using existing randomized controlled trials (RCTs).

DATA SYNTHESIS

Available databases, including PubMed/MEDLINE, Web of Science, Scopus, Cochrane Library, and Embase, were searched to find relevant RCTs up to June 2021. The effect size was expressed as weighted mean difference (WMD) and 95% confidence interval (CI).

CONCLUSION

A total of 20 RCT studies with 2676 participants were included in this article. Our analyses have shown that omega-3 supplementation significantly reduced plasma Hcy levels (WMD: 1.34 μmol/L; 95% CI: 1.97 to -0.72; P < 0.001) compared to the control group. The results of subgroup analysis showed that omega-3 supplementation during the intervention <12 weeks and with a dose ≥3 gr per day causes a more significant decrease in Hcy levels than the intervention ≥12 weeks and at a dose <3 gr. In addition, omega-3 supplements appear to have more beneficial effects in individuals with high levels of normal Hcy. This meta-analysis showed that omega-3 supplementation significantly improved Hcy. However, further studies are needed to confirm the findings.

Reduction of Polyunsaturated Fatty Acids with Tumor Progression in a Lean Non-Alcoholic Steatohepatitis-Associated Hepatocellular Carcinoma Mouse Model

Background and Aim: Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in Western countries. While obesity and diabetes are the hallmarks of NAFLD, it also develops in lean individuals in the absence of metabolic syndrome, with a prevalence of 7 percent in the U.S. and 25-30 percent in some Asian countries. NAFLD represents the spectrum of liver disease, starting with excess liver fat accumulation (NAFL) that can progress to nonalcoholic steatohepatitis (NASH), cirrhosis and ultimately hepatocellular carcinoma (HCC). To date, the pathogenesis of lean NASH-HCC is poorly understood and a mouse model is lacking. We aimed to develop a mouse model of lean NASH-HCC using a choline deficient and high trans-fat/sucrose/cholesterol diet to enable better understanding of its molecular pathogenesis. Methods: C57BL/6N mice were fed this diet starting at 4 weeks of age for 52 weeks and were compared to mice fed an isocaloric low fat control diet for the same duration. C57BL/6N mice were chosen instead of the C57BL/6J mice due to the high susceptibility of C57BL/6J mice to diet-induced obesity. The plasma and tumor fatty acid profile of these mice was also investigated. Results: Nearly 61% of the mice developed lean NASH-HCC. These mice showed reduction of plasma polyunsaturated fatty acids (PUFAs) (linolenic acids (α and γ, ω-3 and ω-6, respectively), eicosapentanoic acid (ω-3), docosahexanoic acid (ω-3), and linoleic acid (ω-6)) and increasing levels over time in mice with pre-malignant lesions. Conclusions: We developed a novel high penetrance diet-induced lean NASH-HCC mouse model. Plasma PUFA levels were reduced with tumor progression in parallel with reduced expression of genes controlling desaturase expression suggesting their potential use as biomarkers for lean NASH-HCC progression as well as chemopreventive molecules.

The effects of omega-3 fatty acids on diabetic nephropathy: A meta-analysis of randomized controlled trials

OBJECTIVE

To evaluate the effects of omega-3 long-chain polyunsaturated fatty acids on proteinuria, estimated glomerular filtration rate (eGFR) and metabolic biomarkers among patients with diabetes.

STUDY DESIGN

Meta-analysis of randomized controlled clinical trials (RCTs).

SETTING & SUBJECTS

Patients with diabetes.

SELECTION CRITERIA FOR STUDIES

We conducted electronic searches in PubMed, Embase and Cochrane Central Register of Controlled Trials from January 1960 to April 2019 to identify RCTs, which examined the effects of omega-3 fatty acids on proteinuria, eGFR and metabolic biomarkers among diabetic patients.

RESULTS

Ten RCTs with 344 participants were included in our meta-analysis. Omega-3 fatty acids reduced the amount of proteinuria among type 2 diabetes mellitus (type 2 DM) and type 1 diabetes mellitus (type 1 DM). This association was only significant among type 2 DM (SMD = -0.29 (95% CI: -0.54, -0.03; p = 0.03). Only studies with duration of intervention of 24 weeks or longer demonstrated a significant lower proteinuria among omega-3 fatty acids compared to control group (SMD = -0.30 (95% CI: -0.58, -0.02; p = 0.04). There was a higher eGFR for both type 1 and type 2 DM groups among omega-3 fatty acids compared to control group, however, the effect was not statistically significant. Regarding serum total cholesterol, LDL-cholesterol and HbA1C, there was no significant difference comparing omega-3 fatty acids to control group. There was a non-significant systolic blood pressure reduction in the omega-3 fatty acids supplementation group compared to control.

CONCLUSION

Omega-3 fatty acids could help ameliorate proteinuria among type 2 DM who received omega-3 supplementation for at least 24 weeks without adverse effects on HbA1C, total serum cholesterol and LDL-cholesterol.

The Link between Homocysteine and Omega-3 Polyunsaturated Fatty Acid: Critical Appraisal and Future Directions

Omega-3 polyunsaturated fatty acids and B vitamins are linked to metabolic and degenerative disorders, such as cardiovascular disease and cognitive decline. In the last two decades, the interplay between B vitamins and omega-3 polyunsaturated fatty acids gained increasing attention. Expression control on enzymes involved in the pathway of homocysteine by polyunsaturated fatty acids has been proposed. The methylation process seems crucial for the metabolism of polyunsaturated fatty acids and their distribution within the body. This review summarizes the available data in humans about the link between homocysteine and omega-3 polyunsaturated fatty acids, with a special focus on the meta-analyses of randomized clinical trials. Even if the paucity of available information about the topic does not allow for definitive conclusions, a synergic action between polyunsaturated fatty acids and B vitamins may play a key role in regulating several metabolic pathways. This element could explain a stronger action on homocysteine levels when omega-3 polyunsaturated fatty acids and B vitamins are supplemented simultaneously. To date, a robust rationale of intervention to prevent metabolic diseases is lacking and could be beneficial for individual health and healthcare policy.

Fatty Acid Profile and Cardiometabolic Markers in Relation with Diet Type and Omega-3 Supplementation in Spanish Vegetarians

Plant-based diets are becoming increasingly popular, and scientific information concerning the nutritional status in this population is needed. This study determined the fatty acid profile of Spanish lacto-ovo vegetarians (LO-vegetarians) and vegans. Participants were 104 healthy adults, LO-vegetarians (n = 49) and vegans (n = 55). Lifestyle habits and consumption of food and omega-3 supplements were estimated by questionnaires. BMI, blood pressure, and abdominal and body fat were determined. Serum was collected to analyze fatty acids, glucose, lipids, homocysteine, insulin, and leptin. Volunteers were classified according to serum omega-6 to omega-3 (n-6/n-3) ratio into three groups: n-6/n-3 < 10, n-6/n-3 ≥ 10 to 20, and n-6/n-3 > 20. Results showed low cardiovascular risk and high insulin sensitivity with negligible differences between diet types. Linoleic acid (C18:2n-6) was the major serum fatty acid, followed by oleic (C18:1n-9) and palmitic (C16:0) acids. In contrast, serum eicosapentaenoic acid (EPA, C20:5n-3) and docosahexaenoic acid (DHA, C22:6n-3) were (median, interquartile range) 0.27, 0.18% and 1.59, and 0.93%, respectively. Users of n-3 supplements (<10% of total vegetarians) had significantly higher EPA than non-users, while frequent consumption of flax-seeds was associated with increased α-linolenic acid (C18:3n-3). However, neither n-3 supplementation nor food consumption affected DHA levels in this vegetarian population.

New Areas of Interest: Is There a Role for Omega-3 Fatty Acid Supplementation in Patients With Diabetes and Cardiovascular Disease?

PURPOSE OF REVIEW

Summarize studies on omega-3 fatty acids in prevention of albuminuria in subjects with diabetes.

RECENT FINDINGS

Several small, short-term trials suggested benefit on albuminuria in subjects with diabetes; however, results were not definitive. Welty et al. showed that eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) for 1 year slowed progression of early-stage albuminuria in subjects with diabetes with clinical coronary artery disease on an angiotensin-converting enzyme inhibitor or angiotensin-receptor blocker, the majority of whom had an albumin/creatinine ratio (ACR) < 30 μg/mg. Moreover, significantly more (3-fold) subjects on EPA and DHA had a decrease in ACR compared to control, and three on EPA and DHA had a change in category from > 30 μg/mg to < 30 μg/mg, whereas no controls did. Potential mechanisms for benefit are discussed. These results suggest that there is benefit and perhaps even reversal of albuminuria with EPA and DHA at an early stage of disease in those with ACR < 30 μg/mg and those with microalbuminuria (ACR > 30).

Plasma choline, homocysteine and vitamin status in healthy adults supplemented with krill oil: a pilot study

Plasma concentrations of metabolites along the choline oxidation and tryptophan degradation pathways have been linked to lifestyle diseases and dietary habits. This study aimed to investigate how krill oil, a source of ω-3 polyunsaturated fatty acids (PUFAs) with a high phosphatidylcholine content, affected these parameters. The pilot study was conducted as a 28 days intervention in 17 healthy volunteers (18-36 years), who received a supplement of 4.5 g krill oil per day, providing 833 mg ω-3 PUFAs, and 1750 mg phosphatidylcholine. Krill oil supplementation increased fasting plasma choline (+28.4%, p < .001), betaine (+26.6%, p < .001), dimethylglycine (+33.7%, p < .001) and sarcosine (+16.8%, p < .001), whereas no statistically significant changes were seen for plasma glycine, serine, methionine, total homocysteine, cysteine, cystathionine, methionine sulfoxide, folate, cobalamin, B₂-, B₃-, and B₆ vitamers, tryptophan, kynurenines, nicotinamide, vitamin A and vitamin E. In summary, krill oil supplementation influenced choline metabolite levels, but not plasma metabolites of the tryptophan-kynurenine-nicotinamide pathways and vitamins. These observations should be confirmed in a placebo-controlled trial, including an ω-3 PUFA supplement without phospholipids to explore the potential additive effects of the different active ingredients.

The polyunsaturated fatty acid balance in kidney health and disease: A review

Epidemiological studies show that circulating polyunsaturated fatty acids contribute to preserve renal function. In renal disease states there is generally a lack of omega-3 long chain polyunsaturated fatty acids (n-3 LCPUFA) as measured in biological samples, but despite intense research for more than 30 years, it is still unclear how and to what extent their supplementation would benefit kidney disorders. Studies evaluating the n-6 series and the kidney are less frequent. The last compilation of clinical trials with n-3 LCPUFA supplements focusing on renal function and damage dates back to 2012. We here discuss n-3 and n-6 fatty acids in relation to the kidney summarizing single- and double blind randomized controlled trials performed between 2012 and 2016. Nine were sub-studies/post-hoc analyses of previous parent trials. Twelve out of the twenty trials reported on fatty acid profile or fatty acid species. Factors that may explain inconsistent results obtained after supplementation with the n-3 LCPUFA EPA and DHA in kidney disease are discussed such as baseline levels determining response, drug interaction. The need of evaluating fatty acid status before and after intervention is emphasized, to match changes in outcome measure with changes of any fatty acid potentially involved.

Eicosapentaenoic and Docosahexaenoic Acids Attenuate Progression of Albuminuria in Patients With Type 2 Diabetes Mellitus and Coronary Artery Disease

Background

Albuminuria is a marker of inflammation and an independent predictor of cardiovascular morbidity and mortality. The current study evaluated whether eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplementation attenuates progression of albuminuria in subjects with coronary artery disease.

Methods and Results

Two‐hundred sixty‐two subjects with stable coronary artery disease were randomized to either Lovaza (1.86 g of EPA and 1.5 g of DHA daily) or no Lovaza (control) for 1 year. Percent change in urine albumin‐to‐creatinine ratio (ACR) was compared. Mean (SD) age was 63.3 (7.6) years; 17% were women and 30% had type 2 diabetes mellitus. In nondiabetic subjects, no change in urine ACR occurred in either the Lovaza or control groups. In contrast, ACR increased 72.3% (P<0.001) in diabetic subjects not receiving Lovaza, whereas those receiving Lovaza had no change. In diabetic subjects on an angiotensin‐converting enzyme‐inhibitor or angiotensin‐receptor blocker, those receiving Lovaza had no change in urine ACR, whereas those not receiving Lovaza had a 64.2% increase (P<0.001). Change in ACR was directly correlated with change in systolic blood pressure (r=0.394, P=0.01).

Conclusions

EPA and DHA supplementation attenuated progression of albuminuria in subjects with type 2 diabetes mellitus and coronary artery disease, most of whom were on an angiotensin‐converting enzyme‐inhibitor or angiotensin‐receptor blocker. Thus, EPA and DHA supplementation should be considered as additional therapy to an angiotensin‐converting enzyme‐inhibitor or angiotensin‐receptor blocker in subjects with type 2 diabetes mellitus and coronary artery disease.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01624727.

Vitamin B12 among Vegetarians: Status, Assessment and Supplementation

Cobalamin is an essential molecule for humans. It acts as a cofactor in one-carbon transfers through methylation and molecular rearrangement. These functions take place in fatty acid, amino acid and nucleic acid metabolic pathways. The deficiency of vitamin B12 is clinically manifested in the blood and nervous system where the cobalamin plays a key role in cell replication and in fatty acid metabolism. Hypovitaminosis arises from inadequate absorption, from genetic defects that alter transport through the body, or from inadequate intake as a result of diet. With the growing adoption of vegetarian eating styles in Western countries, there is growing focus on whether diets that exclude animal foods are adequate. Since food availability in these countries is not a problem, and therefore plant foods are sufficiently adequate, the most delicate issue remains the contribution of cobalamin, which is poorly represented in plants. In this review, we will discuss the status of vitamin B12 among vegetarians, the diagnostic markers for the detection of cobalamin deficiency and appropriate sources for sufficient intake, through the description of the features and functions of vitamin B12 and its absorption mechanism.

Interventions for lowering plasma homocysteine levels in dialysis patients

BACKGROUND

People with end-stage kidney disease (ESKD) have high rates of cardiovascular events. Randomised controlled trials (RCTs) of homocysteine-lowering therapies have not shown reductions in cardiovascular event rates in the general population. However, people with kidney disease have higher levels of homocysteine and may have different mechanisms of cardiovascular disease. We performed a systematic review of the effect of homocysteine-lowering therapies in people with ESKD.

OBJECTIVES

To evaluate the benefits and harms of established homocysteine lowering therapy (folic acid, vitamin B6, vitamin B12) on all-cause mortality and cardiovascular event rates in patients with ESKD.

SEARCH METHODS

We searched Cochrane Kidney and Transplant's Specialised Register to 25 January 2016 through contact with the Information Specialist using search terms relevant to this review.

SELECTION CRITERIA

Studies conducted in people with ESKD that reported at least 100 patient-years of follow-up and assessed the effect of therapies that are known to have homocysteine-lowering properties were included.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data using a standardised form. The primary outcome was cardiovascular mortality. Secondary outcomes included all-cause mortality, incident cardiovascular disease (fatal and nonfatal myocardial infarction and coronary revascularisation), cerebrovascular disease (stroke and cerebrovascular revascularisation), peripheral vascular disease (lower limb amputation), venous thromboembolic disease (deep vein thrombosis and pulmonary embolism), thrombosis of dialysis access, and adverse events. The effects of homocysteine-lowering therapies on outcomes were assessed with meta-analyses using random-effects models. Prespecified subgroup and sensitivity analyses were conducted.

MAIN RESULTS

We included six studies that reported data on 2452 participants with ESKD. Interventions investigated were folic acid with or without other vitamins (vitamin B6, vitamin B12). Participants' mean age was 48 to 65 years, and proportions of male participants ranged from 50% to 98%.Homocysteine-lowering therapy probably leads to little or no effect on cardiovascular mortality (4 studies, 1186 participants: RR 0.93, 95% CI 0.70 to 1.22). There was no evidence of heterogeneity among the included studies (I² = 0%). Homocysteine-lowering therapy had little or no effect on all-cause mortality or any other of this review's secondary outcomes. All prespecified subgroup and sensitivity analyses demonstrated little or no difference. Reported adverse events were mild and there was no increase in the incidence of adverse events from homocysteine-lowering therapies (3 studies, 1248 participants: RR 1.12, 95% CI 0.51 to 2.47; I(2) = 0%). Overall, studies were assessed as being at low risk of bias and there was no evidence of publication bias.

AUTHORS' CONCLUSIONS

Homocysteine-lowering therapies were not found to reduce mortality (cardiovascular and all-cause) or cardiovascular events among people with ESKD.

A combination of omega-3 fatty acids, folic acid and B-group vitamins is superior at lowering homocysteine than omega-3 alone: A meta-analysis

The aim of the study was to assess whether omega-3 polyunsaturated fatty acid supplementation alone or in combination with folic acid and B-group vitamins is effective in lowering homocysteine. The Medline Ovid, Embase and Cochrane databases were searched for randomized-controlled trial studies that intervened with omega-3 supplementation (with or without folic acid) and measured changes in homocysteine concentration. Studies were pooled using a random effects model for meta-analysis. Three different models were analyzed: all trials combined, omega-3 polyunsaturated fatty acid trials, and omega-3 polyunsaturated fatty acids with folic acid and B-group vitamin trials. Nineteen studies were included, consisting of 3267 participants completing 21 trials. Studies were heterogeneous; varying by dose, duration and participant health conditions. Across all trials, omega-3 supplementation was effective in lowering homocysteine by an average of 1.18μmol/L (95%CI: (-1.89, -0.48), P=.001). The average homocysteine-lowering effect was greater when omega-3 supplementation was combined with folic acid and B-group vitamins (-1.37μmol/L, 95%CI: (-2.38, -0.36), P<.01) compared to omega-3 supplementation alone (-1.09μmol/L 95%CI: (-2.04, -0.13), P=.03). Omega-3 polyunsaturated fatty acid supplementation was associated with a modest reduction in homocysteine. For the purposes of reducing homocysteine, a combination of omega-3s (0.2-6g/day), folic acid (150 - 2500μg/day) and vitamins B6 and B12 may be more effective than omega-3 supplementation alone.

The relationship between hyperhomocysteinemia and neurodegeneration

Homocysteine (Hcy) is a key junction in methionine metabolism. In inherited forms of hyperhomocysteinemia patients develop early vascular damage and cognitive decline. Hyperhomocysteinemia is a common consequence of dietary, behavioral and pathological conditions and is epidemiologically related to different diseases, among them neurodegenerative ones are receiving progressively more attention in the last years. Several detrimental mechanisms that see in Hcy a possible promoter seem to be implicated in neurodegeneration (protein structural and functional modifications, oxidative stress, cellular metabolic derangements, epigenetic modifications, pathological aggregates deposition, endothelial damage and atherothrombosis). Interventional studies exploring B group vitamins administration in terms of prevention of Hcy-related cognitive decline and cerebrovascular involvement have shown scant results. In this review, current and possible alternative/complementary approaches are discussed.

Erythrocyte fatty acid profiles and plasma homocysteine, folate and vitamin B6 and B12 in recurrent depression: Implications for co-morbidity with cardiovascular disease

Oxidative stress induced interactions between fatty acid (FA) and one-carbon metabolism may be involved in co-occurrence of major depressive disorder (MDD) and cardiovascular disease (CVD), which have been scarcely studied together. In 137 recurrent MDD-patients vs. 73 age- and sex-matched healthy controls, we simultaneously measured key components of one-carbon metabolism in plasma (homocysteine, folate, vitamins B6 and B12), and of FA-metabolism in red blood cell membranes [main polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid (AA) and structural FA-indices (chain length, unsaturation, peroxidation)]. Results show significant positive associations of folate with EPA, DHA, and the peroxidation index, which were similar in patients and controls. After correction for confounders, these associations were lost except for EPA. Associations between B-vitamins and FA-parameters were non-significant, but also similar in patients and controls. Homocysteine and DHA were significantly less negatively associated in patients than in controls. In conclusion, these data indicate similarities but also differences in associations between parameters of one-carbon and FA-metabolism in recurrent MDD patients vs. controls, which may reflect differences in handling of oxidative stress. Further research should test the consequences of these differences, particularly the premature development of CVD in MDD.

Effect of polyunsaturated fatty acids on homocysteine metabolism through regulating the gene expressions involved in methionine metabolism

The objective was to investigate the regulatory effect of polyunsaturated fatty acids (PUFAs) on mRNA expression of key genes involved in homocysteine (Hcy) metabolism. Eighty male Sprague Dawley rats were randomly divided into eight groups. The oils were orally administered daily for 8 weeks. Plasma Hcy, phospholipids fatty acids, and mRNA expression were determined. Compared with the control group, plasma Hcy was significantly decreased in the 22:6n-3 and conjugated linoleic acid (CLA) groups; mRNA expression of Mthfr was significantly upregulated in the 22:6n-3, 20:5n-3, and 18:3n-3 groups and downregulated in the 18:2n-6 and stearolic acid (SO) groups. Mat1a was upregulated in the 22:6n-3, 20:5n-3, 18:3n-3, and CLA groups. In addition, Cbs was upregulated in the 22:6n-3, 20:5n-3, 18:3n-3 and CLA groups while downregulated in 18:2n-6 and SO groups. Dietary 22:6n-3 and CLA decrease the plasma concentration of Hcy. mRNA expression of Mthfr, Mat1a, Cbs and Pemt, Gnmt, Mtrr, and Bad is upregulated by n-3 PUFA and downregulated by n-6 PUFA. CLA upregulates mRNA expression of Mat1a and Cbs.

Biological effects of add-on eicosapentaenoic acid supplementation in diabetes mellitus and co-morbid depression: a randomized controlled trial

Background

Eicosapentaenoic acid (EPA) may reduce increased risks for (cardiovascular) morbidity and mortality in patients with diabetes mellitus (DM) and comorbid major depressive depression (MDD). Yet, effects of EPA-supplementation on biological risk factors for adverse outcomes have not been studied in DM-patients with MDD.

Methods

We performed a randomized, double-blind trial (n = 25) comparing add-on ethyl-EPA-supplementation to placebo on (I) oxidative stress, (II) inflammatory, (III) hypothalamic-pituitary-adrenal (HPA)-axis, (IV) one-carbon-cycle, (V) fatty acid metabolism and (VI) lipoprotein parameters during 12-weeks' follow-up.

Results

Besides increases in supplemented α-tocopherol [estimate (95% CI); 3.62 (1.14–6.11) µmol/l; p = 0.006] and plasma and erythrocyte EPA, the intervention did not influence other oxidative stress, inflammatory or one-carbon-cycle parameters compared to placebo. HPA-axis reactivity significantly decreased in the EPA-group (N = 12) [AUC_i: −121.93 (−240.20–−3.47) min×nmol/l; p = 0.045], not in the placebo-group (N = 12). Furthermore, EPA-supplementation increased erythrocyte and plasma docosapentaenoic acid, and decreased plasma arachidonic acid (AA) concentrations [−1.61 (−3.10–−0.11) %; p = 0.036]. Finally, EPA had a multivariate influence on lipoprotein concentrations (p = 0.030), reflected by relative increases in high density lipoprotein [HDL; 0.30 (0.02–0.58) mmol/l; p = 0.039] and total cholesterol concentrations [1.01 (0.29–1.72) mmol/l; p = 0.008].

Conclusion

Overall, add-on EPA-supplementation had limited effects on biological risk factors for adverse outcome in this sample of DM-patients with comorbid MDD. Besides increases in concentrations of supplemented α-tocopherol and EPA, AA decreased, and inconclusive effects on HPA-axis (re)activity and lipoprotein concentrations were observed. Therefore, further studies on the alleged beneficial effects of EPA-supplementation on biological risk factors for adverse outcome in DM-patients with comorbid MDD seem warranted, preferably using clinical outcomes such as (cardiovascular) DM-complications.

Trial Registration

Controlled-Trials.com ISRCTN30877831 ISRCTN30877831

Associations of plasma phospholipid fatty acids with plasma homocysteine in Chinese vegetarians

The association of plasma phospholipid (PL) fatty acid composition with plasma homocysteine (Hcy) in Chinese vegetarians is not understood. The main aim of the present study was to investigate the plasma PL fatty acid status, and its association with plasma Hcy in Chinese vegetarians and omnivores. A total of 103 male vegetarians and 128 male omnivores were recruited in Linyin Temple, Hangzhou. Plasma Hcy and PL fatty acid concentrations were determined by standard methods. Compared with omnivores, plasma PL n-3 PUFA (P< 0·001), 22 : 6n-3 (P< 0·001), 22 : 5n-6 (P= 0·021), 22 : 2n-6 (P< 0·001) and SFA (P= 0·017) were significantly lower, while plasma PL n-6 PUFA (P= 0·007) and total PUFA (P< 0·001) were significantly higher in vegetarians. The prevalence of hyperhomocysteinaemia (HHcy) in vegetarians (26·47 %) was significantly higher than that in omnivores (13·28 %). In vegetarians, plasma PL 22 : 6n-3 (r − 0·257, P= 0·046) was significantly negatively associated with plasma Hcy. In omnivores, plasma PL 18 : 1n-7 (r 0·237, P= 0·030) was significantly positively associated with plasma Hcy. Plasma PL 22 : 6n-3 (r − 0·217, P= 0·048) was negatively associated with plasma Hcy in omnivores. Plasma PL SFA were positively associated with the prevalence of HHcy. It would seem appropriate for vegetarians to increase their dietary n-3 PUFA and decrease dietary SFA, and thus reduce the risk of HHcy.

Effects of flaxseed oil on anti-oxidative system and membrane deformation of human peripheral blood erythrocytes in high glucose level

BACKGROUND

The erythrocyte membrane lesion is a serious diabetic complication. A number of studies suggested that n-3 fatty acid could reduce lipid peroxidation and elevate α- or γ-tocopherol contents in membrane of erythrocytes. However, evidence regarding the protective effects of flaxseed oil, a natural product rich in n-3 fatty acid, on lipid peroxidation, antioxidative capacity and membrane deformation of erythrocytes exposed to high glucose is limited.

METHODS

Human peripheral blood erythrocytes were isolated and treated with 50 mM glucose to mimic hyperglycemia in the absence or presence of three different doses of flaxseed oil (50, 100 or 200 μM) in the culture medium for 24 h. The malondialdehyde (MDA) and L-glutathione (GSH) were measured by HPLC and LC/MS respectively. The phospholipids symmetry and membrane fatty acid composition of human erythrocytes were detected by flow cytometry and gas chromatograph (GC). The morphology of human erythrocyte was illuminated by ultra scanning electron microscopy.

RESULTS

Flaxseed oil attenuated hyperglycemia-induced increase of MDA and decrease of GSH in human erythrocytes. Human erythrocytes treated with flaxseed oil contained higher C22:5 and C22:6 than those in the 50 mM glucose control group, indicating that flaxseed oil could reduce lipid asymmetric distribution and membrane perturbation. The ultra scanning electron microscopy and flow cytometer have also indicated that flaxseed oil could protect the membrane of human erythrocytes from deformation at high glucose level.

CONCLUSION

The flaxseed oil supplementation may prevent lipid peroxidation and membrane dysfunction of human erythrocytes in hyperglycemia.

Fatty acids as biocompounds: their role in human metabolism, health and disease: a review. part 2: fatty acid physiological roles and applications in human health and disease

BACKGROUND

This is the second of two review parts aiming at describing the major physiological roles of fatty acids, as well as their applications in specific conditions related to human health.

RESULTS

The review included the current literature published in Pubmed up to March 2011. In humans, fatty acids are a principle energy substrate and structural components of cell membranes (phospholipids) and second messengers. Fatty acids are also ligands of nuclear receptors affecting gene expression. Longer-chain (LC) polyunsaturated fatty acids (PUFA), including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid are precursors of lipid mediators such as eicosanoids (prostaglandins, leukotrienes, thromboxanes), resolvins and neuroprotectins. Lipid mediators produced by EPA and DHA (LC n-3 PUFA; mainly found in oily fish) are considered as inflammation-resolving, and thus, fish oil has been characterised as antiinflammatory. Recommendations for EPA plus DHA intake from oily fish vary between 250-450 mg/day. Dietary reference values for fat vary between nutrition bodies, but mainly agree on a low total and saturated fat intake. The existing literature supports the protective effects of LC n-3 PUFA (as opposed to n-6 PUFA and saturated fat) in maternal and offspring health, cardiovascular health, insulin sensitivity, the metabolic syndrome, cancer, critically ill patients, and immune system disorders.

CONCLUSION

Fatty acids are involved in multiple pathways and play a major role in health. Further investigation and a nutrigenomics approach to the effects of these biocompounds on health and disease development are imperative and highlight the importance of environmental modifications on disease outcome.

MAT1A variants modulate the effect of dietary fatty acids on plasma homocysteine concentrations

BACKGROUND AND AIM

Dietary n-3 polyunsaturated fatty acids (PUFAs) are associated with decreased plasma homocysteine (Hcy), an important biomarker for cardiovascular disease. The S-adenosylmethionine synthetase type-1 (MAT1A), an essential enzyme in the conversion of methionine to S-adenosylmethionine, plays a key role in homocysteine metabolism. This study investigated the interaction between dietary fatty acids and MAT1A genotypes on plasma Hcy concentrations among Boston Puerto Ricans.

METHODS AND RESULTS

Plasma Hcy and MAT1A genotypes were determined in 994 subjects of the Boston Puerto Rican Health Study. Dietary fatty acid intakes were assessed by interviews using a questionnaire adapted from the NCI/Block food frequency form.

RESULT

In the cross-sectional analysis, genetic variant MAT1A 3U1510 displayed a significant interaction with dietary n-3:n-6 PUFA ratio in determining plasma Hcy (p-value for interaction = 0.025). 3U1510G homozygotes had significantly lower plasma Hcy concentration than major allele homozygotes and heterozygotes (AA + AG) (p-value for trend = 0.019) when the n-3:n-6 ratio was >0.09. Two other MAT1A variants, d18777 and i15752, also showed significant interactions with different constituents of dietary fat influencing Hcy concentrations. Furthermore, haplotypes consisting of three variants displayed a strong interaction with n3:n6 ratio influencing Hcy concentrations.

CONCLUSIONS

Our results suggest that MAT1A genotypes appear to modulate effects of dietary fat on plasma Hcy.

High consumption of Ω-3 polyunsaturated fatty acids decrease plasma homocysteine: a meta-analysis of randomized, placebo-controlled trials

OBJECTIVE

High consumption of ω-3 polyunsaturated fatty acids (PUFAs) has been associated with lower plasma homocystine (Hcy) levels, but intervention studies in humans have been inconclusive. The objective was to systematically evaluate the effects of ω-3 PUFA supplementation on plasma Hcy levels.

METHODS

A comprehensive search of Medline, EMBASE, the Cochrane Clinical Trials Registry, and bibliographies of relevant articles published from 1966 through September 2010 was undertaken. All randomized, placebo-controlled trials that compared ω-3 PUFA supplementation with placebo were included. Two investigators performed data extraction and quality scoring independently, with discrepancies resolved by consensus.

RESULTS

Eleven trials including 702 subjects were analyzed. The outcomes studied were plasma Hcy level. Eleven randomized, placebo-controlled trials were included in this meta-analysis. Supplementation with ω-3 PUFAs was associated with a significant decrease in plasma Hcy level (weighted mean difference -1.59 μmol/L, 95% confidence interval -2.34 to -0.83) compared with control subjects.

CONCLUSION

This meta-analysis suggested that ω-3 PUFA supplementation can decrease plasma Hcy levels. The implications of these findings remain to be elucidated.

Effect of a fat spread enriched with medium-chain triacylglycerols and a special fatty acid-micronutrient combination on cardiometabolic risk factors in overweight patients with diabetes

BACKGROUND

Medium-chain triacylglycerols (MCT), omega-3 polyunsaturated fatty acids (n-3-PUFA) and micronutrients may be useful for weight and cardiometabolic risk management. However, studies analyzing the effect of a combination of both in individuals at increased cardiometabolic risk are lacking. Therefore, this randomized, controlled, double-blind study investigated the effect of a fat spread enriched with two different doses of MCT and a special long-chain fatty acid-micronutrient combination on cardiometabolic risk factors in overweight diabetic patients.

METHODS

Fifty-four patients received either a fat spread with 6 g/d MCT (MCT30%) or 1.2 g/d (MCT6%). Forty-three completed the study. Analysis was performed according to the median of MCT intake (supplemented and food-derived MCT). Clinical, anthropometric, blood, 24 h-urine parameters and dietary intake were assessed at baseline and after 12 weeks.

RESULTS

Total MCT intake > 7 g/d (MCT > 7 group) significantly reduced waist circumference (WC) by 1.81 ± 2.69 cm, whereas ≤ 7 g/d MCT (MCT ≤ 7 group) increased WC by 0.32 ± 3.03 cm (p = 0.027), which was supported by a change in waist-to-height ratio (WHtR) (p = 0.018). Fasting serum triglycerides (TG) increased in both groups over time due to dietary habits. In contrast, diabetic metabolic situation and urinary albumin excretion did not alter. Urinary pH differed significantly between groups after 12 weeks.

CONCLUSION

An intake of >7 g/d MCT reduced WC in overweight diabetics, whereas the increase in the intake of fatty acids may have worsened fasting TG. Therefore, the suitability of a fat for nutrient enrichment remains to be challenged, and further studies in low-fat matrices are desirable.

Methylenetetrahydrofolate reductase variants associated with hypertension and cardiovascular disease interact with dietary polyunsaturated fatty acids to modulate plasma homocysteine in puerto rican adults

Although methylenetetrahydrofolate reductase (MTHFR) genetic variants are associated with plasma homocysteine (Hcy) and cardiovascular disease (CVD), little is known whether dietary fatty acid intake modulates these associations. The goal was to examine the interaction of MTHFR variants with dietary fatty acids influencing plasma Hcy in 995 Boston Puerto Rican adults. We found that plasma Hcy concentration was negatively correlated with (n-3) PUFA intake (r = -0.117; P = 0.022), and the ratio of (n-3):(n-6) PUFA in the diet (r = -0.122; P = 0.009). Further, 2 functional MTHFR variants, 1298A>C and 677C>T, which are not in linkage disequilibrium in this population, were significantly associated with hypertension (OR = 1.72, P = 0.024, and OR = 1.60, P = 0.002, respectively). In addition, the 1298A>C variant was significantly associated with CVD (OR = 3.32; P = 0.030). Importantly, this variant exhibited significant interactions with intakes of total and (n-6) PUFA and the (n-3):(n-6) PUFA ratio of the diet. The plasma Hcy concentration of carriers of risk allele 1298C was greater than that of noncarriers only when participants had consumed a high-PUFA diet (>7.8% energy) but was not greater when they had low intake of PUFA (≤7.8% energy). In addition, participants with combined genotypes of both SNP (677 TT with 1298 AC or CC) who consumed high levels of (n-3) PUFA (>0.66% energy) had lower plasma Hcy compared with those who had the same genotype and consumed low levels of (n-3) PUFA (≤0.66% energy). Our study suggests that dietary PUFA intake modulates the effect of 2 MTHFR variants on plasma Hcy in Boston Puerto Rican adults.

Chemistry behind Vegetarianism

This review summarizes the effect of a habitual vegetarian diet on clinical complications in relation to chemistry and biochemistry. Omnivores have a significantly higher cluster of cardiovascular risk factors compared with vegetarians, including increased body mass index, waist to hip ratio, blood pressure, plasma total cholesterol (TC), triacylglycerol and LDL-C levels, serum lipoprotein(a) concentration, plasma factor VII activity, ratios of TC/HDL-C, LDL-C/HDL-C and TAG/HDL-C, and serum ferritin levels. Compared with omnivores, vegetarians, especially vegans, have lower serum vitamin B₁₂ concentration and n-3 polyunsaturated fatty acid (PUFA) levels in the tissue membrane phospholipids, which are associated with increased collagen and ADP stimulated ex vivo whole blood platelet aggregation, plasma 11-dehydrothromboxane B₂, and homocysteine levels and decreased plasma HDL-C. This may be associated with an increased thrombotic and atherosclerotic risk. It is suggested that vegetarians, especially vegans, should increase their dietary n-3 PUFA and vitamin B₁₂ intakes.

Functional food ingredients as adjunctive therapies to pharmacotherapy for treating disorders of metabolic syndrome

Abstract Information regarding the use of functional foods and nutraceuticals (FFN) in combating disease is rarely communicated to health care practitioners as medicinal strategies for patients. Metabolic syndrome (MetS) is an ideal paradigm for demonstrating the therapeutic properties of FFN. Encompassing multiple etiologies, including atherogenic dyslipidemia, insulin resistance, and hypertension, MetS affects over a third of American adults. However, as disease-related risk factors accumulate over time, guidelines for treating disorders of MetS progressively de-emphasize the use of FFN. Using marine omega-3 fatty acids, plant sterols, fiber, and tomato extract as examples, the purpose of this review is to endorse FFN as long-term adjunctive therapies to pharmaceutical treatment for disorders and risk factors for MetS. An additional goal is to compare physiological and molecular targets of FFN against corresponding prescription medications. Results reveal that FFN are viable treatment strategies for disorders of MetS, complementing pharmacological interventions by targeting and improving the biological processes that foster the development of disease. Thus, efficacious FFN therapies should be emphasized throughout all stages of treatment as adjuncts to pharmacotherapy for disorders of MetS. Accordingly, new developments in FFN research must be implemented into clinical guidelines with the prospect of improving disease prognoses as accessories to prescription medications.

Advances in ingredient and processing systems for meat and meat products

Changes in consumer demand of meat products as well as increased global competition are causing an unprecedented spur in processing and ingredient system developments within the meat manufacturing sector. Consumers demand healthier meat products that are low in salt, fat, cholesterol, nitrites and calories in general and contain in addition health-promoting bioactive components such as for example carotenoids, unsaturated fatty acids, sterols, and fibers. On the other hand, consumers expect these novel meat products with altered formulations to taste, look and smell the same way as their traditionally formulated and processed counterparts. At the same time, competition is forcing the meat processing industry to use the increasingly expensive raw material "meat" more efficiently and produce products at lower costs. With these changes in mind, this article presents a review of novel ingredient systems and processing approaches that are emerging to create high quality, affordable meat products not only in batch mode but also in large-scale continuous processes. Fat replacers, fat profile modification and cholesterol reduction techniques, new texture modifiers and alternative antioxidant and antimicrobial systems are being discussed. Modern processing equipment to establish continuously operating product manufacturing lines and that allow new meat product structures to be created and novel ingredients to be effectively utilized including vacuum fillers, grinders and fine dispersers, and slicers is reviewed in the context of structure creation in meat products. Finally, trends in future developments of ingredient and processing systems for meat products are highlighted.

Docosahexaenoic acid decreases plasma homocysteine via regulating enzyme activity and mRNA expression involved in methionine metabolism

OBJECTIVE

The objective of this study was to investigate the regulatory effect of fish oil rich in omega-3 polyunsaturated fatty acids (PUFAs) on critical enzyme activity and mRNA expression involved in homocysteine (Hcy) metabolism.

METHODS

Thirty-six male Sprague-Dawley rats aged 3 wk, weighing 120 +/- 10 g, were randomly divided into three groups: the olive oil (OO) group, the tuna oil (TO) group, and the salmon oil (SO) group. The oil was orally administered every day using a stomach tube. Eight weeks later, plasma Hcy, phospholipids, omega-3 PUFAs, enzyme activity, and mRNA expression in tissues were determined.

RESULTS

Compared with the control group, phospholipids, total omega-3 PUFAs, and omega-3/omega-6 PUFAs in the liver and lung were significantly elevated in the TO and SO groups; 22:6omega-3 in the liver and lung was significantly increased in the TO group; and 20:5omega-3 in the two tissues was significantly elevated in the SO group. The level of plasma Hcy was significantly decreased with TO; methionine adenosyl transferase (MAT) activity was significantly increased and MAT mRNA expression was significantly upregulated with TO; cystathionine-gamma-lyase mRNA expression in TO was significantly upregulated; however, cystathionine beta-synthase and S-adenosylhomocysteine hydrolases were not significantly changed when compared with control.

CONCLUSION

TO rich in 22:6omega-3 decreases the concentration of Hcy despite increasing MAT activity and upregulating MAT mRNA expression through compensatory cystathionine-gamma-lyase mRNA expression, both of which are involved in Hcy metabolism.

Antioxidative enzymes and increased oxidative stress in depressive women

OBJECTIVES

To investigate the activities of the main antioxidative enzymes and oxidative stress in women with depressive disorder (DD).

METHODS

In 35 drug-naive women with DD and 35 age matched healthy women enzymes superoxide dismutase (CuZnSOD), catalase (CAT), glutathione peroxidase (GPX1), glutathione reductase (GR) and paraoxonase (PON1), concentrations of conjugated dienes (CD), reduced glutathione (GSH) and anthropometric and clinical data were investigated.

RESULTS

Women with DD were found to have decreased activities of GPX1 (p<0.05), decreased concentrations of GSH (p<0.05), and increased activities of GR (p<0.05), CuZnSOD (p<0.001), and concentrations of CD (p<0.05). Activity of GPX1 was positively correlated with concentration of GSH (p<0.05). Concentrations of CD were positively correlated with TG (p<0.01).

CONCLUSION

Our set of depressive women was characterized by changes indicating an increased oxidative stress, as well as by certain features of metabolic syndrome.

The effect of n-3 long-chain polyunsaturated fatty acid supplementation on urine protein excretion and kidney function: meta-analysis of clinical trials

BACKGROUND

Chronic kidney disease is a major worldwide problem. Although epidemiologic and experimental studies suggest that n-3 long-chain polyunsaturated fatty acid (n-3 LCPUFA) supplementation may prevent or slow the progression of kidney disease, evidence from clinical trials is inconsistent.

OBJECTIVE

The objective was to combine evidence from controlled clinical trials to assess the effect of n-3 LCPUFA supplementation on the change in urine protein excretion (UPE) and on glomerular filtration rate (GFR).

DESIGN

We performed a meta-analysis of clinical trials that tested the effect of n-3 LCPUFA supplementation on UPE, a marker of kidney damage, and on GFR, a marker of kidney function. A random-effects model was used to pool SD effect size (Cohen's d) across studies.

RESULTS

Seventeen trials with 626 participants were included in the meta-analysis. Most trials focused on patients with a single underlying diagnosis: IgA nephropathy (n = 5), diabetes (n = 7), or lupus nephritis (n = 1). The dose of n-3 LCPUFAs ranged from 0.7 to 5.1 g/d, and the median follow-up was 9 mo. In the pooled analysis, there was a greater reduction in UPE in the n-3 LCPUFA group than in the control group: Cohen's d for all trials was -0.19 (95% CI: -0.34, -0.04; P = 0.01). In a patient with 1 g UPE/d , this corresponds to a reduction of 190 mg/d. Effects on GFR were reported in 12 trials. The decline in GFR was slower in the n-3 LCPUFA group than in the control group, but this effect was not significant (0.11; 95% CI: -0.07, 0.29; P = 0.24).

CONCLUSIONS

In our meta-analysis, use of n-3 LCPUFA supplements reduced UPE but not the decline in GFR. However, small numbers of participants in trials, different methods of assessing proteinuria and GFR, and inconsistent data reporting limit the strength of these conclusions. Large, high-quality trials with clinical outcomes are warranted.

Omega-3 fatty acids and the cardiometabolic syndrome

Benefits of fish consumption in patients with the cardiometabolic syndrome relate to the high biologic value of protein, omega-3 fatty acids, as well as certain minerals and vitamins in fish. Recently, the American Heart Association issued new guidelines for the intake of omega-3 oils for the prevention of coronary heart disease. The objective of this paper is to evaluate the potential health benefits of fish consumption and/or fish oil supplements in reducing cardiometabolic syndrome risk factors. The consumption of fish or fish oil containing omega-3 polyunsaturated fatty acids reduces the risk of coronary heart disease, decreases triglyceride, blood pressure, and inflammatory markers, improves endothelial function, prevents certain cardiac arrhythmias, reduces platelet aggregation (including reactivity and adhesion), reduces vasoconstriction, enhances fibrinolysis, reduces fibrin formation, and decreases the risk of microalbuminuria and sudden cardiac death. Thus, fish intake or fish oil supplement use is beneficial to reduce cardiometabolic risk factors.

Fish oil in the treatment of dyslipidemia

PURPOSE OF REVIEW

The recent availability of a concentrated prescription omega-3 fatty acid preparation provides physicians with an additional anti-dyslipidemic agent at a time when limitations of statin therapy in dyslipidemic high-risk patients are recognized. This review examines the evidence supporting the use of omega-3 fatty acid treatment in dyslipidemic states.

RECENT FINDINGS

There is now considerable evidence that omega-3 fatty acid treatment at the prescription strength of 4 g/day effectively and safely lowers triglyceride levels and increases low-density lipoprotein size, as well as affecting high-density lipoprotein metabolism. Similar effects have been noted in patients treated with statins, and add-on prescription omega-3 fatty acid therapy significantly increases the proportion of statin-treated dyslipidemic patients reaching their non-high-density lipoprotein cholesterol goals. In addition to past studies showing a cardioprotective effect of low-dose omega-3 fatty acid treatment against sudden death, a recent controlled clinical trial showed that 1.8 g of omega-3 fatty acid in statin-treated patients reduced major coronary events by 19% compared with statin plus placebo treatment.

SUMMARY

Omega-3 fatty acid treatment should be considered in patients with severe hypertriglyceridemia as well as in high-risk patients with an atherogenic lipoprotein phenotype.

Omega-3 fatty acid supplementation and total homocysteine levels in end-stage renal disease patients

AIM

Elevated total homocysteine (tHcy) levels are commonplace among end-stage renal disease (ESRD) patients increasing risk for poor cardiovascular outcomes. Specifically, when plasma levels become significantly elevated, tHcy levels appear to contribute to vascular damage and premature atherosclerosis. The purpose of this study was to examine the effect of an over-the-counter omega-3 (n-3) fatty acid supplementation on tHcy levels in ESRD patients undergoing chronic haemodialysis.

METHODS

The present study was conducted using a double-blind, permuted-randomized and placebo-controlled experimental protocol. ESRD patients were followed prospectively while supplementing n-3 or corn oil (n-6) prospectively for 6 months.

PATIENTS

Sixty-nine patients were recruited that had previously demonstrated compliance with dialysis and medication. Following a 12 h fast, participants donated 12 mL of blood for analysis of tHcy at baseline and at 6 months.

RESULTS

The results of this study using regression models revealed no differences in age and gender regarding homocysteine levels at the post-test with P-values of 0.6818, 0.6709 and 0.3331 for each regression model. The study findings also revealed that daily administration of 6 g of n-3 fatty acids containing 160 mg of eicosapentaenic acid (0.96 g/day) and 100 mg of docosahexaenoic acid (0.6 g/day) had no effect on tHcy levels when compared with control.

CONCLUSION

Potential reasons for this non-significant result may be found in a dose-response relationship, advancement of disease progression in our sample population, or potentially the lack of a significant relationship between fish oil and tHcy. Future studies should address whether a dose-response relationship between n-3 fatty acid supplementation and tHcy levels exists, and how stage of disease progression affects intervention success or failure.

Effect of n-3 fatty acid supplementation on blood glucose, lipid profile and cytokines in humans: A pilot study

This study was undertaken to evaluate the effects of n-3 fatty acid supplementation on blood glucose, lipid profile and cytokines in humans. Twenty adult healthy subjects were supplemented with 1g/day fish oil concentrate capsules for 2 weeks. Fasting blood samples were taken at baseline and again after 2 week intervention. Fish oil supplementation significantly lowered fasting serum concentrations of total cholesterol, triacylglycerol, very low density lipoprotein and low density lipoprotein (P < 0.01). Also high density lipoprotein increased significantly compared with baseline value (P < 0.01). Fish oil did not significantly altere the fasting blood glucose concentration but significantly reduced the serum cytokines (P < 0.001). This study demonstrated that eicosapentanoic acid (EPA) and docosahexaenoic acid (DHA) supplementation altered serum lipids, lipoprotein and cytokine concentrations in normal human subjects even at the small dose of 660 mg of EPA plus DHA per day. It appears that EPA plus DHA can be a safe and perhaps beneficial supplement to inflammatory diseases.