Effects of prescription omega-3-acid ethyl esters on fasting lipid profile in subjects with primary hypercholesterolemia

Changes in lipoprotein particle subclasses, standard lipids, and apolipoproteins after supplementation with n-3 or n-6 PUFAs in abdominal obesity: A randomized double-blind crossover study

BACKGROUND & AIMS

Marine-derived omega-3 (n-3) polyunsaturated fatty acids (PUFAs), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), lower circulating levels of triacylglycerols (TAGs), and the plant-derived omega-6 (n-6) PUFA linoleic acid (LA) may reduce cholesterol levels. Clinical studies on effects of these dietary or supplemental PUFAs on other blood fat fractions are few and have shown conflicting results. This study aimed to determine effects of high-dose supplemental n-3 (EPA + DHA) and n-6 (LA) PUFAs from high-quality oils on circulating lipoprotein subfractions and standard lipids (primary outcomes), as well as apolipoproteins, fatty acids, and glycemic control (secondary outcomes), in females and males with abdominal obesity.

METHODS

This was a randomized double-blind crossover study with two 7-wk intervention periods separated by a 9-wk washout phase. Females (n = 16) were supplemented with 3 g/d of EPA + DHA (TAG fish oil) or 15 g/d of LA (safflower oil), while males (n = 23) received a dose of 4 g/d of EPA + DHA or 20 g/d of LA. In fasting blood samples, we investigated lipoprotein particle subclasses by nuclear magnetic resonance spectroscopy, as well as standard lipids, apolipoproteins, fatty acid profiles, and glucose and insulin. Data were analyzed by linear mixed-effects modeling with 'subjects' as the random factor.

RESULTS

The difference between interventions in relative change scores was among the lipoprotein subfractions significant for total very-low-density lipoproteins (VLDLs) (n-3 vs. n-6: -38%∗ vs. +16%, p < 0.001; ∗: significant within-treatment change score), large VLDLs (-58%∗ vs. -0.91%, p < 0.001), small VLDLs (-57%∗ vs. +41%∗, p < 0.001), total low-density lipoproteins (LDLs) (+5.8%∗ vs. -4.3%∗, p = 0.002), large LDLs (+23%∗ vs. -2.1%, p = 0.004), total high-density lipoproteins (HDLs) (-6.0%∗ vs. +3.7%, p < 0.001), large HDLs (+11%∗ vs. -5.3%, p = 0.001), medium HDLs (-24%∗ vs. +6.2%, p = 0.030), and small HDLs (-9.9%∗ vs. +9.6%∗, p = 0.002), and among standard lipids for TAGs (-16%∗ vs. -2.6%, p = 0.014), non-esterified fatty acids (-19%∗ vs. +5.5%, p = 0.033), and total cholesterol (-0.28% vs. -4.4%∗, p = 0.042). A differential response in relative change scores was also found for apolipoprotein (apo)B (+0.40% vs. -6.0%∗, p = 0.008), apoA-II (-6.0%∗ vs. +1.5%, p = 0.001), apoC-II (-11%∗ vs. -1.7%, p = 0.025), and apoE (+3.3% vs. -3.8%, p = 0.028).

CONCLUSIONS

High-dose supplementation of high-quality oils with n-3 (EPA + DHA) or n-6 (LA) PUFAs was followed by reductions in primarily TAG- or cholesterol-related markers, respectively. The responses after both interventions point to changes in the lipoprotein-lipid-apolipoprotein profile that have been associated with reduced cardiometabolic risk, also among people with TAG or LDL-C levels within the normal range.

REGISTRATION

Registered under ClinicalTrials.gov Identifier: NCT02647333.

CLINICAL TRIAL REGISTRATION

Registered at https://clinicaltrials.gov/ct2/show/NCT02647333.

Low-Dose Omega-3 Fatty Acid and Vitamin D for Anthropometric, Biochemical Blood Indices and Respiratory Function. Does it work?

Abstract. Omega-3 fatty acids and vitamin D3 have beneficial effects on different blood, cardiovascular parameters and physical performance. However, the effect of low-dose omega-3 fatty acid supplementation remains unclear. 84 office workers aged 40–60 years, participated in a 16-week open, randomized, placebo-controlled, parallel-group study. The experimental group received 330 mg of omega-3 fatty acid and 0.005 mg (200 IU) of vitamin D3 per day and the control group received placebo. Anthropometric, biochemical blood and respiratory indices were measured at 12 and 16 weeks. Body mass (BM) and body mass index (BMI) significantly reduced in both the experimental (BM from 74.4 ± 13.04 to 73.2 ± 13.02 kg, p < 0.001; BMI from 25.8 ± 4.1 to 25.4 ± 4.3 kg/m2, p < 0.001) and the placebo groups (BM from 69.5 ± 11. to 68.7 ± 11.4 kg, p < 0.05; BMI from 24.1 ± 4.0 to 23.8 ± 4.2 kg/m2, p < 0.05). Omega-3 fatty acid supplementation significantly improved glucose (from 5.12 ± 0.55 to 4.97 ± 0.62 mmol/l; p = 0.05), total cholesterol (from 5.86 ± 1.0 to 5.32 ± 1.55 mmol/l; p = 0.003), and vitamin D levels (from 35.07 ± 21.65 to 68.63 ± 25.94 nmol/l; p = 0.000). Maximal oxygen consumption (from 33.7 ± 2.4 to 36.6 ± 3.2 ml/kg/min, p = 0.035), forced vital capacity (from 3.5 ± 0.6 to 3.9 ± 0.9 l, p = 0.044), forced expiratory volume (from 3.2 ± 0.6 to 3.5 ± 0.7 l, p = 0.014), and peak expiratory flow (from 6.7 ± 1.4 to 7.5 ± 1.6 l/s, p = 0.019) also slightly improved in the omega-3 fatty acid group. Daily supplementation of 330 mg of omega-3 fatty acids had a slight positive impact on total cholesterol and glucose level, while there was no effect on low and high density lipoproteins, and triglycerides levels. Therefore, dose of 330 mg per day seems as insufficient.

Severe hypertriglyceridemia. Clinical characteristics and therapeutic management

INTRODUCTION

The therapeutic management of severe hypertriglyceridaemia represents a clinical challenge.

OBJECTIVES

The objectives of this study were 1) to identify the clinical characteristics of patients with severe hypertriglyceridaemia, and 2) to analyse the treatment established by the physicians in each case.

METHODS

A cross-sectional study was carried out using the computerised medical records of all patients>18 years of age with a blood triglyceride level≥1,000mg/dL between 1 January 2011 and 31 December 2016. Clinical and laboratory variables were collected. The behaviour of the physicians in the 6 months after the lipid finding was analysed.

RESULTS

A total of 420 patients were included (mean age 49.1±11.4 years, males 78.8%). The median of triglycerides was 1,329mg/dL (interquartile range 1,174-1,658). No secondary causes were found in 34.1% of the patients. The most frequent secondary causes were obesity (38.6%) and diabetes (28.1%). Physical activity was recommended and a nutritionist was referred to in 49.1% and 44.2% of the patients, respectively. Secondary causes were identified and attempts were made to correct them in 40.7% of cases. The most indicated pharmacological treatments were fenofibrate 200mg/day (26.5%) and gemfibrozil 900mg/day (19.3%). Few patients received the indication of omega 3 fatty acids or niacin.

CONCLUSION

This study showed, for the first time in our country, the characteristics of a population with severe hypertriglyceridaemia. The therapeutic measures instituted by the physicians were insufficient. Knowing the characteristics in this particular clinical scenario could improve the current approach of these patients.

Use of supplemental long-chain omega-3 fatty acids and risk for cardiac death: An updated meta-analysis and review of research gaps

BACKGROUND

Randomized controlled trials (RCTs) assessing use of long-chain omega-3 polyunsaturated fatty acids (LC-OM3), primarily eicosapentaenoic acid, and/or docosahexaenoic acid have shown mixed results.

OBJECTIVE

The objectives of the study were to update and further explore the available RCT data regarding LC-OM3 supplementation and risk for cardiac death and to propose testable hypotheses for the mixed results obtained in RCTs regarding supplemental LC-OM3 use and cardiac risk.

METHODS

A literature search was conducted using PubMed and Ovid/MEDLINE for RCTs assessing LC-OM3 supplements or pharmaceuticals with intervention periods of at least 6 months and reporting on the outcome of cardiac death. Meta-analysis was used to compare cumulative frequencies of cardiac death events between the LC-OM3 and control groups, including sensitivity and subset analyses.

RESULTS

Fourteen RCTs were identified for the primary analysis (71,899 subjects). In the LC-OM3 arms, 1613 cardiac deaths were recorded (4.48% of subjects), compared with 1746 cardiac deaths in the control groups (4.87% of subjects). The pooled relative risk estimate showed an 8.0% (95% confidence interval 1.6%, 13.9%, P = .015) lower risk in the LC-OM3 arms vs controls. Subset analyses showed numerically larger effects (12.9%-29.1% lower risks, all P < .05) in subsets of RCTs with eicosapentaenoic acid + docosahexaenoic acid dosages >1 g/d and higher risk samples (secondary prevention, baseline mean or median triglycerides ≥150 mg/dL, low-density lipoprotein cholesterol ≥130 mg/dL, statin use <40% of subjects). Heterogeneity was low (I² ≤ 15.5%, P > .05) for the primary and subset analyses.

CONCLUSION

LC-OM3 supplementation is associated with a modest reduction in cardiac death.

Dietary Strategies and Novel Pharmaceutical Approaches Targeting Serum ApoA-I Metabolism: A Systematic Overview

The incidence of CHD is still increasing, which underscores the need for new preventive and therapeutic approaches to decrease CHD risk. In this respect, increasing apoA-I concentrations may be a promising approach, especially through increasing apoA-I synthesis. This review first provides insight into current knowledge on apoA-I production, clearance, and degradation, followed by a systematic review of dietary and novel pharmacological approaches to target apoA-I metabolism. For this, a systematic search was performed to identify randomized controlled intervention studies that examined effects of whole foods and (non)nutrients on apoA-I metabolism. In addition, novel pharmacological approaches were searched for, which were specifically developed to target apoA-I metabolism. We conclude that both dietary components and pharmacological approaches can be used to increase apoA-I concentrations or functionality. For the dietary components in particular, more knowledge about the underlying mechanisms is necessary, as increasing apoA-I per se does not necessarily translate into a reduced CHD risk.

Effect of diets rich in either saturated fat or n-6 polyunsaturated fatty acids and supplemented with long-chain n-3 polyunsaturated fatty acids on plasma lipoprotein profiles

BACKGROUND/OBJECTIVES

Abnormalities in lipoprotein profiles (size, distribution and concentration) play an important role in the pathobiology of atherosclerosis and coronary artery disease. Dietary fat, among other factors, has been demonstrated to modulate lipoprotein profiles. We aimed to investigate if background dietary fat (saturated, SFA versus omega-6 polyunsaturated fatty acids, n-6PUFA) was a determinant of the effects of LCn-3PUFA supplementation on lipoprotein profiles.

SUBJECTS/METHODS

A randomized controlled clinical intervention trial in a parallel design was conducted. Healthy subjects (n=26) were supplemented with 400 mg eicosapentaenoic acid plus 2000 mg docosahexaenoic acid daily and randomized to consume diets rich in either SFA or n-6PUFA for a period of 6 weeks. Blood samples, collected at baseline and after 6 weeks of intervention, were assessed for plasma lipoprotein profiles (lipoprotein size, concentration and distribution in subclasses) determined using nuclear magnetic resonance spectroscopy.

RESULTS

Study participants receiving the SFA or the n-6PUFA enriched diets consumed similar percentage energy from fat (41 and 42% respectively, P=0.681). However, subjects on the SFA diet consumed 50% more energy as saturated fat and 77% less as linoleic acid than those consuming the n-6PUFA diet (P<0.001). The diets rich in SFA and n-6PUFA reduced the concentration of total very-low-density lipoprotein (VLDL) particles (P<0.001, both), and their subclasses and increased VLDL (P=0.042 and P=0.007, respectively) and LDL (P=0.030 and 0.027, respectively) particle size. In addition, plasma triglyceride concentration was significantly reduced by LCn-3PUFA supplementation irrespective of the dietary fat.

CONCLUSIONS

LCn-3PUFA modulated lipoprotein profiles in a similar fashion when supplemented in diets rich in either SFA or n-6PUFA.

Effect of long chain omega-3 polyunsaturated fatty acids on inflammation and metabolic markers in hypertensive and/or diabetic obese adults: a randomized controlled trial

Background

Obesity is a degree of excess weight that predisposes people to metabolic syndromes via an inflammatory mechanism. Hypertensive and diabetic people have higher risks of developing systemic inflammation. Long chain omega-3 polyunsaturated fatty acids (LC ω-3 PUFAs) can reduce the cardiovascular events and help against inflammation.

Objective

To identify the effects of LC ω-3 PUFAs on reducing the levels of inflammatory markers on hypertensive and/or diabetic obese adults.

Materials and methods

Sixty-four patients, who were hypertensive and/or diabetic obese with high levels of inflammatory markers, from primary healthcare centers of Gaza City, Palestine, enrolled in two groups of an open-label, parallel, randomized, controlled trial for 8 weeks. Thirty-three patients were in the control group, and 31 patients were in the experimental group. The experimental group was treated with a daily dose of 300 mg eicosapentaenoic acid and 200 mg of docosahexaenoic acid.

Results

Treatment with LC ω-3 PUFAs significantly reduced the level of high sensitivity C reactive protein (hs-CRP) [14.78±10.7 to 8.49±6.69 mg/L, p<0.001], fasting blood glucose (FBG) [178.13±58.54 to 157.32±59.77 mg/dL, p=0.024], and triglyceride (TG) [209.23±108.3 to 167.0±79.9 mg/dL, p<0.05] after 8 weeks of treatment, whereas no significant changes appeared in interleukin 6 (IL-6) and total cholesterol (TC). In the control group, significant reduction was detected for FBG [187.15±64.8 to 161.91±37.9 mg/dL, p<0.05] and TG [202.91±107.0 to 183.45±95.82 mg/dL, p<0.05], and no changes for hs-CRP, IL-6, or TC. By comparing the experimental group with the changes of control group at the endpoint, LC ω-3 PUFAs did not reach the clinical significance in treating effectiveness for any of the clinical variables.

Conclusion

LC ω-3 PUFAs have recommended effects on health; the obtained results can improve the role of LC ω-3 PUFAs as a protective factor on inflammation and metabolic dysregulation. The time allowed or the dose used could be insufficient to achieve full treatment affectivity.

Krill oil reduces plasma triacylglycerol level and improves related lipoprotein particle concentration, fatty acid composition and redox status in healthy young adults - a pilot study

Background

Lipid abnormalities, enhanced inflammation and oxidative stress seem to represent a vicious circle in atherogenesis, and therapeutic options directed against these processes seems like a reasonable approach in the management of atherosclerotic disorders. Krill oil (RIMFROST Sublime®) is a phospholipid-rich oil with eicosapentaenoic acid (EPA): docosahexaenoic acid (DHA) ratio of 1.8:1. In this pilot study we determined if krill oil could favourable affect plasma lipid parameters and parameters involved in the initiation and progression of atherosclerosis.

Methods

The study was conducted as a 28 days intervention study examining effect-parameters of dietary supplementation with krill oil (832.5 mg EPA and DHA per day). 17 healthy volunteers in the age group 18–36 (mean age 23 ± 4 years) participated. Plasma lipids, lipoprotein particle sizes, fatty acid composition in plasma and red blood cells (RBCs), plasma cytokines, antioxidant capacity, acylcarntines, carnitine, choline, betaine, and trimethylamine-N-oxide (TMAO) were measured before and after supplementation.

Results

Plasma triacylglycerol (TAG) and large very-low density lipoprotein (VLDL) & chylomicron particle concentrations decreased after 28 days of krill oil intake. A significant reduction in the TAG/HDL cholesterol resulted. Krill oil supplementation decreased n-6/n-3 polyunsaturated fatty acids (PUFA) ratio both in plasma and RBCs. This was due to increased EPA, DHA and docosapentaenoic acid (DPA) and reduced amount of arachidonic acid (AA). The increase of n-3 fatty acids and wt % of EPA and DHA in RBC was of smaller magnitude than found in plasma. Krill oil intake increased the antioxidant capacity, double bond index (DBI) and the fatty acid anti-inflammatory index. The plasma atherogenicity index remained constant whereas the thrombogenicity index decreased. Plasma choline, betaine and the carnitine precursor, γ-butyrobetaine were increased after krill oil supplementation whereas the TMAO and carnitine concentrations remained unchanged.

Conclusion

Krill oil consumption is considered health beneficial as it decreases cardiovascular disease risk parameters through effects on plasma TAGs, lipoprotein particles, fatty acid profile, redox status and possible inflammation. Noteworthy, no adverse effects on plasma levels of TMAO and carnitine were found.

Comparison of the Effects of Eicosapentaenoic Acid With Docosahexaenoic Acid on the Level of Serum Lipoproteins in Helicobacter pylori: A Randomized Clinical Trial

Background:

Helicobacter pylori infection is the most common chronic bacterial infection around the world and an important cause of gastrointestinal disorders, which might be involved in the pathogenesis of some extragastrointestinal disturbances as well as changes in serum lipid profile. Hypolipemic properties of omega-3 fatty acids have been studied in several studies.

Objectives:

The present study aimed to compare the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplementation on the level of serum lipoproteins in H. pylori.

Patients and Methods:

In a randomized, double-blinded, placebo-controlled clinical trial in Iran, 105 Helicobacter pylori were randomly allocated to receive 2 g of daily EPA (35 patients), DHA (35 patients), or medium-chain triglyceride (MCT) oil as placebo (33 patients) along with conventional tetra-drug H. pylori eradication regimen for 12 weeks.

Results:

From 105 included patients, 97 (31 in EPA, 33 in DHA, and 33 in control groups) completed the study and were included in final analysis. The levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and the ratios of TG/HDL-C, TC/HDL-C, and LDL-C/HDL-C were not significantly different among the three groups, while the level of triglyceride (TG) was statistically different. DHA (-16.6 ± 30.34) and control (+ 15.32 ± 56.47) groups were statistically different with regard to changes in TG levels (P = 0.000).

Conclusions:

There was no difference between the effects of 2 g of EPA or DHA supplementation for 12 weeks on the levels of total cholesterol, LDL-C, HDL-C, TC/HDL-C, TG/HDL-C, and LDL-C/HDL-C; however, it had a desirable effect on the level of TG in a way that the effect of DHA was clearer.

Effect of the amount and type of dietary fat on cardiometabolic risk factors and risk of developing type 2 diabetes, cardiovascular diseases, and cancer: a systematic review

The effects of both the amount and quality of dietary fat have been studied intensively during the past decades. Previously, low-fat diets were recommended without much attention to the quality of fat, whereas there is general emphasis on the quality of fat in current guidelines. The objective of this systematic review (SR) was to assess the evidence of an effect of the amount and type of dietary fat on body weight (BW), risk factors, and risk of non-communicable diseases, that is, type 2 diabetes (T2DM), cardiovascular diseases (CVD), and cancer in healthy subjects or subjects at risk for these diseases. This work was performed in the process of updating the fourth edition of the Nordic Nutrition Recommendations from 2004. The literature search was performed in October 2010 covering articles published since January 2000. A complementary search was done in February 2012 covering literature until December 2011. Two authors independently selected articles for inclusion from a total of about 16,000 abstracts according to predefined criteria. Randomized controlled trials (RCT) and prospective cohort studies (PCS) were included as well as nested case-control studies. A few retrospective case-control studies were also included when limited or no data were available from other study types. Altogether 607 articles were quality graded and the observed effects in these papers were summarized. Convincing evidence was found that partial replacement of saturated fat (SFA) with polyunsaturated fat (PUFA) or monounsaturated fat (MUFA) lowers fasting serum/plasma total and LDL cholesterol concentrations. The evidence was probable for a decreasing effect of fish oil on concentration of serum/plasma total triglycerides as compared with MUFA. Beneficial effect of MUFA both on insulin sensitivity and fasting plasma/serum insulin concentration was considered as probable in comparisons of MUFA and carbohydrates versus SFA, whereas no effect was found on fasting glucose concentration in these comparisons. There was probable evidence for a moderate direct association between total fat intake and BW. Furthermore, there was convincing evidence that partial replacement of SFA with PUFA decreases the risk of CVD, especially in men. This finding was supported by an association with biomarkers of PUFA intake; the evidence of a beneficial effect of dietary total PUFA, n-6 PUFA, and linoleic acid (LA) on CVD mortality was limited suggestive. Evidence for a direct association between total fat intake and risk of T2DM was inconclusive, whereas there was limited-suggestive evidence from biomarker studies that LA is inversely associated with the risk of T2DM. However, there was limited-suggestive evidence in biomarker studies that odd-chain SFA found in milk fat and fish may be inversely related to T2DM, but these associations have not been supported by controlled studies. The evidence for an association between dietary n-3 PUFA and T2DM was inconclusive. Evidence for effects of fat on major types of cancer was inconclusive regarding both the amount and quality of dietary fat, except for prostate cancer where there was limited-suggestive evidence for an inverse association with intake of ALA and for ovarian cancer for which there was limited-suggestive evidence for a positive association with intake of SFA. This SR reviewed a large number of studies focusing on several different health outcomes. The time period covered by the search may not have allowed obtaining the full picture of the evidence in all areas covered by this SR. However, several SRs and meta-analyses that covered studies published before year 2000 were evaluated, which adds confidence to the results. Many of the investigated questions remain unresolved, mainly because of few studies on certain outcomes, conflicting results from studies, and lack of high quality-controlled studies. There is thus an evident need of highly controlled RCT and PCS with sufficient number of subjects and long enough duration, specifically regarding the effects of the amount and quality of dietary fat on insulin sensitivity, T2DM, low-grade inflammation, and blood pressure. New metabolic and other potential risk markers and utilization of new methodology in the area of lipid metabolism may provide new insight.

Icosapent ethyl for the treatment of severe hypertriglyceridemia

Hypertriglyceridemia is a highly prevalent lipid abnormality and it is associated with atherosclerosis, with a growing body of evidence linking elevated triglycerides (TGs) with cardiovascular disease. The current major omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA) combination, lowers serum TGs while often increasing levels of low-density lipoprotein cholesterol. Icosapent ethyl is an omega-3 polyunsaturated fatty acid with a 96% pure ethyl ester of EPA that has been recently approved for lowering TG levels in patients with very high TGs (≥500 mg/dL), and it does so without significantly affecting serum low-density lipoprotein cholesterol. The potential benefits of omega-3 fatty acid therapy for dyslipidemias will be discussed, including the potential pros and cons of EPA alone versus the more common and readily available EPA/DHA combination therapy.

Eicosapentaenoic and docosahexaenoic acid ethyl esters differentially enhance B-cell activity in murine obesity

EPA and DHA are not biologically equivalent; however, their individual activity on B cells is unknown. We previously reported fish oil enhanced murine B-cell activity in obesity. To distinguish between the effects of EPA and DHA, we studied the ethyl esters of EPA and DHA on murine B-cell function as a function of time. We first demonstrate that EPA and DHA maintained the obese phenotype, with no improvements in fat mass, adipose inflammatory cytokines, fasting insulin, or glucose clearance. We then tested the hypothesis that EPA and DHA would increase the frequency of splenic B cells. EPA and DHA differentially enhanced the frequency and/or percentage of select B-cell subsets, correlating with increased natural serum IgM and cecal IgA. We next determined the activities of EPA and DHA on ex vivo production of cytokines upon lipopolysaccharide stimulation of B cells. EPA and DHA, in a time-dependent manner, enhanced B-cell cytokines with DHA notably increasing IL-10. At the molecular level, EPA and DHA differentially enhanced the formation of ordered microdomains but had no effect on Toll-like receptor 4 mobility. Overall, the results establish differential effects of EPA and DHA in a time-dependent manner on B-cell activity in obesity, which has implications for future clinical studies.

Omega-3 polyunsaturated fatty acids in the treatment of atherogenic dyslipidemia

Epidemiological studies have established an association between high triglycerides (TG) plasma levels and increased cardiovascular risk. Increased TG levels, commonly coupled with low HDL-C levels, are common in high cardiovascular risk subjects including those with dyslipidemia, metabolic syndrome and type 2 diabetes. Management of hypertriglyceridemia (HTG) includes lifestyle modification for mild-to-moderate HTG and pharmacological therapies for the treatment of high and very high TG levels. Among drugs, fibrates, nicotinic acid and omega-3 polyunsaturated fatty acids may be considered. Omega-3 fatty acids reduce plasma TG levels by several mechanisms; beside the effects on TG, omega-3 can also influence the levels of other lipids and lipoproteins including HDL-C and LDL-C. Clinical trials have also shown that omega-3 fatty acid supplementation is effective also when added in combination with other lipid-lowering drugs. These findings suggest that omega-3 fatty acids may be usefully considered for the management of high TG levels.

Effect of stearidonic acid-enriched soybean oil on fatty acid profile and metabolic parameters in lean and obese Zucker rats

Background

Consumption of marine-based oils high in omega-3 polyunsaturated fatty acids (n3PUFAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) is known to protect against obesity-related pathologies. It is less clear whether traditional vegetable oils with high omega-6 polyunsaturated fatty acid (n6PUFA) content exhibit similar therapeutic benefits. As such, this study examined the metabolic effects of a plant-based n3PUFA, stearidonic acid (SDA), in polygenic obese rodents.

Methods

Lean (LZR) and obese Zucker (OZR) rats were provided either a standard westernized control diet (CON) with a high n6PUFA to n3PUFA ratio (i.e., 16.2/1.0) or experimental diet modified with flaxseed (FLAX), menhaden (FISH), or SDA oil that resulted in n6PUFA to n3PUFA ratios of 1.7/1.0, 1.3/1.0, and 1.0/0.8, respectively.

Results

After 12 weeks, total adiposity, dyslipidemia, glucose intolerance, and hepatic steatosis were all greater, whereas n3PUFA content in liver, adipose, and muscle was lower in OZR vs. LZR rats. Obese rodents fed modified FISH or SDA diets had lower serum lipids and hepatic fat content vs. CON. The omega-3 index (i.e., ΣEPA + DHA in erythrocyte membrane) was 4.0, 2.4, and 2.0-fold greater in rodents provided FISH, SDA, and FLAX vs. CON diet, irrespective of genotype. Total hepatic n3PUFA and DHA was highest in rats fed FISH, whereas both hepatic and extra-hepatic EPA was higher with FISH and SDA groups.

Conclusions

These data indicate that SDA oil represents a viable plant-derived source of n3PUFA, which has therapeutic implications for several obesity-related pathologies.

Systematic review: Evaluating the effect of lipid-lowering therapy on lipoprotein and lipid values

PURPOSE

This systematic review was performed to summarize published experience using low density lipoprotein particle number (LDL-P) to monitor the efficacy of lipid-lowering pharmacotherapies.

METHODS

Studies were identified from a literature search of MEDLINE (January 1, 2000 - June 30, 2012); and abstract searches of select conferences. All accepted studies reported mean (or median) nuclear magnetic resonance (NMR)-based LDL-P values for at least 10 subjects receiving lipid lowering pharmacotherapy.

RESULTS

Searches revealed 36 studies (with 61 treatment arms) in which LDL-P measurements were reported pre- and post-treatment. Most studies also reported changes in low-density lipoprotein cholesterol (LDL-C), but fewer studies reported changes in apolipoprotein B (apoB)(n = 20) and non-HDL-C (n = 28). Treatments included statins (22 arms/15 studies), fibrates (7 arms/7 studies), niacin (7 arms/6 studies), bile acid sequestrants (5 arms/2 studies), an anti-apoB oligonucleotide (2 arms/2 studies), combination therapies (8 arms/6 studies), anti-diabetics (5 arms/4 studies), and, other treatments (5 arms/2 studies). Lipid-lowering pharmacotherapy resulted in reductions in mean LDL-P in all but two studies. In several statin studies, the percent reductions in LDL-P were smaller than reductions in LDL-C, comparable changes were reported when LDL-P and apoB, were reported.

CONCLUSIONS

Study-level data from this systemic review establish that different lipid lowering agents can lead to discordance between LDL-P and LDL-C, therefore, basing LDL-lowering therapy only on the achievement of cholesterol goals may result in a treatment gap. Therefore, the use of LDL-P for monitoring lipid-lowering therapy, particularly for statins, can provide a more accurate assessment of residual cardiovascular risk.

n-3 PUFAs enhance the frequency of murine B-cell subsets and restore the impairment of antibody production to a T-independent antigen in obesity

The role of n-3 polyunsaturated fatty acids (PUFA) on in vivo B-cell immunity is unknown. We first investigated how n-3 PUFAs impacted in vivo B-cell phenotypes and antibody production in the absence and presence of antigen compared with a control diet. Lean mice consuming n-3 PUFAs for 4 weeks displayed increased percentage and frequency of splenic transitional 1 B cells. Upon stimulation with trinitrophenylated-lipopolysaccharide, n-3 PUFAs increased the number of splenic transitional 1/2, follicular, premarginal, and marginal zone B cells. n-3 PUFAs also increased surface, but not circulating, IgM. We next tested the effects of n-3 PUFAs in a model of obesity that is associated with suppressed humoral immunity. An obesogenic diet after ten weeks of feeding, relative to a lean control, had no effect on the frequency of B cells but lowered circulating IgM upon antigen stimulation. Administration of n-3 PUFAs to lean and obese mice increased the percentage and/or frequency of transitional 1 and marginal zone B cells. Furthermore, n-3 PUFAs in lean and obese mice increased circulating IgM relative to controls. Altogether, the data show n-3 PUFAs enhance B cell-mediated immunity in vivo, which has implications for immunocompromised populations, such as the obese.

Omega-3 polyunsaturated fatty acids in the treatment of hypertriglyceridaemia

Hypertriglyceridaemia (HTG) is an independent risk factor for cardiovascular disease; high-risk patients with HTG, such as those with metabolic syndrome or diabetes, may benefit from hypolipidaemic therapies. Several lipid-lowering drugs act by reducing triglyceride (TG) levels, including fibrates, nicotinic acid and omega-3 fatty acids. The omega-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) dose-dependently reduce plasma TG levels; the effect tends to be greater in patients with higher TG levels at baseline. Evidence from clinical trials suggests that EPA+DHA doses of ≥ 2 g/day are required to achieve significant effects. The optimal TG-lowering doses of EPA+DHA are 3-4 g/day, with little evidence to support lipid-altering efficacy of doses of EPA and DHA <1g/day. Predicted changes in fasting serum TG levels at the recommended dietary intakes of EPA and/or DHA of 200-500 mg/day are -3.1% to -7.2%. Reductions of plasma TG levels at the optimal doses are from 25-35% up to 45% in the presence of severely elevated TG levels (≥ 500 mg/dl; ≥ 5.65 mmol/l), along with a reduction in non-high-density lipoprotein-cholesterol (non-HDL-C) and an increase in HDL-C. This observation has also been confirmed in statin-treated patients.

Ω3 fatty acids may reduce hyperlipidemia in pediatric renal transplant recipients

Life expectancy after pediatric renal transplantation remains lower than that of the normal population largely due to cardiovascular morbidity and mortality. Hyperlipidemia is a potentially modifiable risk factor for cardiovascular morbidity. Retrospective chart review of all available pediatric renal transplant patients (26) in a single center with assessment of anthropometry, renal function, steroid, calcineurin or mTOR inhibitor exposure and Ω3 FA supplementation. Eighteen transplant recipients without Ω3 FA supplementation served as control. Nutrition and supplement surveys were conducted with standardized questionnaires. Fasting cholesterol values were compared using the latest value prior to start of Ω3 FA and at last follow-up. Eight patients (five receiving mTOR inhibitor) started Ω3 FA supplementation at a mean dose of 29.2 ± 12 mg of EPA/kg and 16.1 ± 7.4 mg DHA/kg body weight. Median duration of treatment was 2.5 yr (range 0.8-5.9 yr) and their total fasting cholesterol at last follow-up dropped significantly from 5.08 ± 0.97 (control group 3.77 ± 0.81, p = 0.0084) to 4.17 ± 0.54 mm (p = 0.0158). High-density lipoprotein cholesterol increased not significantly from 1.74 ± 0.49 to 2.02 ± 0.93 mm. No patient had increased bleeding. Supplementation of omega-3 FAs may reduce hyperlipidaemia after pediatric renal transplantation.

Application of polyunsaturated fatty acids in internal medicine: beyond the established cardiovascular effects

n-3 Polyunsaturated fatty acids (PUFAs) are organic acids, essential for mammals, whose deficiency is associated with different diseases. The American Heart Association recommends that all adults increase food-derived n-3 PUFA intake and also suggests that patients with documented coronary heart disease consume approximately 1 g of eicosapentaenoic acid and docosahexaenoic acid per day. However, recent evidence broadens their potential application to many other health disorders directly or indirectly associated with cardiovascular disease risk such as rheumatological diseases, mood depression, chronic kidney disease, chronic inflammatory lung diseases and others. These effects seem to be largely dependent on the dosages employed and on the characteristics of the selected patients. The cardiometabolic effects of PUFAs have been largely reviewed elsewhere, so the aim of our review is to point out the potential usefulness of such drugs with pleiotropic effects in the management of the actual typical aging patient, with co-morbidities and multidrug therapies.

Effect of rosuvastatin monotherapy or in combination with fenofibrate or ω-3 fatty acids on lipoprotein subfraction profile in patients with mixed dyslipidaemia and metabolic syndrome

BACKGROUND

Raised triglycerides (TG), decreased high-density lipoprotein cholesterol (HDL-C) levels and a predominance of small dense low density lipoproteins (sdLDL) are characteristics of the metabolic syndrome (MetS).

OBJECTIVE

To compare the effect of high-dose rosuvastatin monotherapy with moderate dosing combined with fenofibrate or ω-3 fatty acids on the lipoprotein subfraction profile in patients with mixed dyslipidaemia and MetS.

METHODS

We previously randomised patients with low-density lipoprotein cholesterol (LDL-C) > 160 and TG > 200 mg/dl to rosuvastatin monotherapy 40 mg/day (R group, n = 30) or rosuvastatin 10 mg/day combined with fenofibrate 200 mg/day (RF group, n = 30) or ω-3 fatty acids 2 g/day (Rω group, n = 30). In the present study, only patients with MetS were included (24, 23 and 24 in the R, RF and Rω groups respectively). At baseline and after 12 weeks of treatment, the lipoprotein subfraction profile was determined by polyacrylamide 3% gel electrophoresis.

RESULTS

The mean LDL size was significantly increased in all groups. This change was more prominent with RF than with other treatments in parallel with its greater hypotriglyceridemic capacity (p < 0.05 compared with R and Rω). A decrease in insulin resistance by RF was also noted. Only RF significantly raised HDL-C levels (by 7.7%, p < 0.05) by increasing the cholesterol of small HDL particles. The cholesterol of larger HDL subclasses was significantly increased by R and Rω.

CONCLUSIONS

All regimens increased mean LDL size; RF was the most effective. A differential effect of treatments was noted on the HDL subfraction profile.

Prescription omega-3-acid ethyl esters reduce fasting and postprandial triglycerides and modestly reduce pancreatic β-cell response in subjects with primary hypertriglyceridemia

Treatment with prescription omega-3-acid ethyl esters (POM3) reduces triglycerides (TG) and TG-rich lipoprotein particles, but has been associated with increased fasting glucose (2-6mg/dL). This double-blind, randomized, controlled crossover trial in 19 men and women with hypertriglyceridemia (fasting TG ≥150 and ≤499mg/dL) examined lipid responses and indices of insulin sensitivity and secretion following a liquid meal tolerance test. Six weeks treatment with POM3 vs. corn oil resulted in significant lower mean fasting (-50.1mg/dL, p<0.001) and postprandial TG (-76.1mg/dL, p<0.001), higher mean fasting glucose (2.8mg/dL, p=0.062), reduced mean disposition index (2.1 vs. 2.4, p=0.037), and no change in the median Matsuda composite insulin sensitivity index (3.3 vs. 3.2, p=0.959). These results suggest that POM3 slightly reduces pancreatic β-cell responsiveness to plasma glucose elevation, which may contribute to the rise in fasting glucose sometimes observed with POM3.

Parenteral fish-oil-based lipid emulsion improves fatty acid profiles and lipids in parenteral nutrition-dependent children

BACKGROUND

Total parenteral nutrition (PN), including fat administered as a soybean oil-based lipid emulsion (SOLE), is a life-saving therapy but may be complicated by PN-induced cholestasis and dyslipidemia. A fish-oil-based lipid emulsion (FOLE) as a component of PN can reverse PN-cholestasis and has been shown to improve lipid profiles.

OBJECTIVE

The objective was to describe changes in the fatty acid and lipid profiles of children with PN-cholestasis who were treated with a FOLE.

DESIGN

Lipid and fatty acid profiles of 79 pediatric patients who developed PN-cholestasis while receiving standard PN with a SOLE were examined before and after the switch to a FOLE. All patients received PN with the FOLE at a dose of 1 g · kg(-1) · d(-1) for ≥1 mo.

RESULTS

The median (interquartile range) age at the start of the FOLE treatment was 91 (56-188) d. After a median (interquartile range) of 18.3 (9.4-41.4) wk of receiving the FOLE, the subjects' median total and direct bilirubin improved from 7.9 and 5.4 mg/dL to 0.5 and 0.2 mg/dL, respectively (P < 0.0001). Serum triglyceride, total cholesterol, LDL, and VLDL concentrations significantly decreased by 51.7%, 17.4%, 23.7%, and 47.9%, respectively.

CONCLUSIONS

The switch from a SOLE to a FOLE in PN-dependent children with cholestasis and dyslipidemia was associated with a dramatic improvement in serum triglyceride and VLDL concentrations, a significant increase in serum omega-3 (n-3) fatty acids (EPA and DHA), and a decrease in serum omega-6 fatty acids (arachidonic acid). A FOLE may be the preferred lipid emulsion in patients with PN-cholestasis, dyslipidemia, or both. This trial is registered at clinicaltrials.gov as NCT00910104.