Treatment with omega-3 polyunsaturated fatty acids does not improve endothelial function in patients with type 2 diabetes and very high cardiovascular risk: A randomized, double-blind, placebo-controlled study (Omega-FMD)

Omega-3 fatty acids effectively mitigate high-sensitivity C-reactive protein (hs-CRP) biomarker of inflammation in acute myocardial infarction patients: a randomized, double-blind, placebo-controlled clinical trial

Myocardial infarction (MI) is considered an inflammatory disease and among the leading causes of death globally. An essential indicator of inflammation, high-sensitivity C-reactive protein (hs-CRP), is linked with the acute MI prognosis. We aimed to examine the impact of omega-3 polyunsaturated fatty acids (PUFAs) as an anti-inflammatory supplement on hs-CRP levels in acute MI patients. Sixty patients with acute MI participated in this randomized, placebo-controlled trial. For 30 days, patients were randomized to receive omega-3 PUFAs (2 g/day, N = 30) or placebo (N = 30) on top of guideline-directed medical therapy. An initial and endpoint measurement of hs-CRP was performed. We found that the hs-CRP levels in both omega-3 PUFAs and placebo groups remarkably decreased following 30 days of treatment (decreasing from 1.84 (2.3) and 1.3 (2.6) to 0.38 (0.54) and 0.63 (1.12) mg/dL, respectively; P < 0.001). Following the 30 days of treatment, the reducing impact of omega-3 PUFAs (↓ 1.54 (1.98) mg/dL) on hs-CRP was more robust than the placebo group (↓ 0.92 (1.57) mg/dL, P = 0.008). Furthermore, the WBC, cholesterol, LDL, and triglyceride levels were markedly decreased in omega-3 and placebo groups after 30 days of therapy (P < 0.001 for all). However, no remarkable differences were reported in the level of these parameters after 30 days of therapy between both studied groups. Our findings showed that omega-3 PUFAs decrease hs-CRP amounts in patients with acute MI. Omega-3 PUFA supplementation may be an appropriate candidate in patients with early-stage acute MI for inhibiting inflammation.

Omega-3 fatty acids and endothelial function: A GRADE-assessed systematic review and meta-analysis

INTRODUCTION

N-3 polyunsaturated fatty acids (PUFAs) supplementation has been reported to have an impact on flow-mediated dilatation (FMD), a conventionally used clinical technique for estimating endothelial dysfunction. However, its proven effects on endothelial function are unclear. This systematic review and meta-analysis were conducted to evaluate the effects of n-3 PUFAs supplementation on FMD of the brachial artery.

METHOD

This study was performed following the PRISMA guidelines. To identify eligible RCTs, a systematic search was completed in PubMed/Medline, Scopus and Web of Science using relevant keywords. A fixed- or random-effects model was utilized to estimate the weighted mean difference (WMD) and 95% confidence interval (95% CI).

RESULTS

Thirty-two studies (with 35 arms) were included in this meta-analysis, involving 2385 subjects with intervention duration ranging from 4 to 48 weeks. The pooled meta-analysis demonstrated a significant effect of omega-3 on FMD (WMD = 0.8%, 95% CI = 0.3-1.3, p = .001) and heterogeneity was significant (I2  = 82.5%, p < .001).

CONCLUSION

We found that n-3 PUFA supplementation improves endothelial function as estimated by flow-mediated dilatation of the brachial artery.

Effects of Omega-3 Fatty Acids on Flow-mediated Dilatation and Carotid Intima Media Thickness: A Meta-analysis

PURPOSE OF REVIEW

To investigate the effects of omega-3 fatty acids on flow-mediated dilatation (FMD) and carotid intima-media thickness (CIMT) and explore the factors influencing these effects.

RECENT FINDINGS

FMD was significantly higher in the omega-3 fatty acid group compared to the control group (mean difference = 0.90%; p = 0.0003). In particular, the subgroup with CHD (both EPA + DHA < 1 g/day and ≥ 1 g/day) and the subgroup without CHD but with CHD risk factors (only EPA + DHA ≥ 1 g/day) showed significantly increased FMD after supplementation of omega-3 fatty acids. CIMT was not significantly different between the omega-3 fatty acid and control groups (standardized mean difference = -0.08; p = 0.26). Subgroup analysis of CHD patients was not conducted because of the limited number of studies. Intake of omega-3 fatty acids improved FMD in patients with CHD and patients with risk factors for CHD. Further research is needed on the effects of omega-3 fatty acids on CIMT.

Omega-3 Fatty Acids in Arterial Hypertension: Is There Any Good News?

Omega-3 polyunsaturated fatty acids (ω-3 PUFAs), including alpha-linolenic acid (ALA) and its derivatives eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are "essential" fatty acids mainly obtained from diet sources comprising plant oils, marine blue fish, and commercially available fish oil supplements. Many epidemiological and retrospective studies suggested that ω-3 PUFA consumption decreases the risk of cardiovascular disease, but results of early intervention trials have not consistently confirmed this effect. In recent years, some large-scale randomized controlled trials have shed new light on the potential role of ω-3 PUFAs, particularly high-dose EPA-only formulations, in cardiovascular prevention, making them an attractive tool for the treatment of "residual" cardiovascular risk. ω-3 PUFAs' beneficial effects on cardiovascular outcomes go far beyond the reduction in triglyceride levels and are thought to be mediated by their broadly documented "pleiotropic" actions, most of which are directed to vascular protection. A considerable number of clinical studies and meta-analyses suggest the beneficial effects of ω-3 PUFAs in the regulation of blood pressure in hypertensive and normotensive subjects. These effects occur mostly through regulation of the vascular tone that could be mediated by both endothelium-dependent and independent mechanisms. In this narrative review, we summarize the results of both experimental and clinical studies that evaluated the effect of ω-3 PUFAs on blood pressure, highlighting the mechanisms of their action on the vascular system and their possible impact on hypertension, hypertension-related vascular damage, and, ultimately, cardiovascular outcomes.

Fatty acids act on vascular endothelial cells and influence the development of cardiovascular disease

Endothelial cells (ECs) maintain the health of blood vessels and prevent the development of cardiovascular disease (CVD). Free saturated fatty acids (FAs) induce EC damage and increase the risk of CVD by promoting arteriosclerosis. Conversely, polyunsaturated FAs (PUFAs), such as docosahexaenoic acid, are thought to suppress EC damage induced during the early stages of CVD. This review describes the effects of multiple dietary FAs on EC disorders involved in the development of CVD. The roles of FAs in atherosclerosis and CVD were analyzed by evaluating articles published in PubMed, Science Direct, and Web of Science. Saturated FAs were found to induce EC damage by reducing the production and action of EC-derived nitric oxide. Oxidative stress, inflammation, and the renin-angiotensin system were found to be involved in EC disorder. Furthermore, n-3 PUFAs were found to reduce EC dysfunction and prevent the development of EC disorder. These results indicate that FAs may affect EC failure induced during the early stages of CVD and reduce the risk of developing the disease.

Eicosapentaenoic and Docosahexaenoic Acid Supplementation Increases HDL Content in n-3 Fatty Acids and Improves Endothelial Function in Hypertriglyceridemic Patients

High-density lipoproteins (HDLs) are known to enhance vascular function through different mechanisms, including the delivery of functional lipids to endothelial cells. Therefore, we hypothesized that omega-3 (n-3) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) content of HDLs would improve the beneficial vascular effects of these lipoproteins. To explore this hypothesis, we performed a placebo-controlled crossover clinical trial in 18 hypertriglyceridemic patients without clinical symptoms of coronary heart disease who received highly purified EPA 460 mg and DHA 380 mg, twice a day for 5 weeks or placebo. After 5 weeks of treatment, patients followed a 4-week washout period before crossover. HDLs were isolated using sequential ultracentrifugation for characterization and determination of fatty acid content. Our results showed that n-3 supplementation induced a significant decrease in body mass index, waist circumference as well as triglycerides and HDL-triglyceride plasma concentrations, whilst HDL-cholesterol and HDL-phospholipids significantly increased. On the other hand, HDL, EPA, and DHA content increased by 131% and 62%, respectively, whereas 3 omega-6 fatty acids significantly decreased in HDL structures. In addition, the EPA-to-arachidonic acid (AA) ratio increased more than twice within HDLs suggesting an improvement in their anti-inflammatory properties. All HDL-fatty acid modifications did not affect the size distribution or the stability of these lipoproteins and were concomitant with a significant increase in endothelial function assessed using a flow-mediated dilatation test (FMD) after n-3 supplementation. However, endothelial function was not improved in vitro using a model of rat aortic rings co-incubated with HDLs before or after treatment with n-3. These results suggest a beneficial effect of n-3 on endothelial function through a mechanism independent of HDL composition. In conclusion, we demonstrated that EPA and DHA supplementation for 5 weeks improved vascular function in hypertriglyceridemic patients, and induced enrichment of HDLs with EPA and DHA to the detriment of some n-6 fatty acids. The significant increase in the EPA-to-AA ratio in HDLs is indicative of a more anti-inflammatory profile of these lipoproteins.

Nutrition-related mobile applications - Should they be used for dietary prevention and treatment of cardiovascular diseases?

BACKGROUND AND AIMS

There is no prior research on the usefulness that popular nutrition-related mobile applications would have in assessing fatty acids intake. In this study, we examine these applications through their utilization in the assessment of consumption of saturated (SFAs) and polyunsaturated (PUFAs) fatty acids against the Polish reference method (RM, Dieta 6.0). This report does also include the information about monounsaturated fatty acids and cholesterol intake.

METHODS AND RESULTS

SFAs and PUFAs intake was assessed using two-day dietary recalls obtained from 120 individuals by 3 selected mobile applications (App1 = Yazio, App2 = MyFitnessPal, App3 = Fitatu) and compared with RM. Despite strong (SFAs by App1 and App3) and moderate (SFAs by App2 and PUFAs by App1, App2, App3) correlations with RM, Bland-Altman analyses showed relevant biases and wide range between limits of agreement. Considering SFAs and MUFAs intake, App1 had the best agreement. App1 had high sensitivity (94.6%) in recognition of subjects with SFAs intake >10% with moderate specificity (67.9%), while App2 had poor sensitivity (27.2%) and high specificity (100%). App3 showed moderate sensitivity and specificity (77.2% and 75%, respectively).

CONCLUSIONS

Mobile applications are not accurate tools in SFAs and PUFAs assessment when compared to the RM. Nonetheless, their ability to recognize SFAs intake >10% energy intake may suggest that further development of mobile applications could potentially become an attractive tool in clinical practice.

Clinical significance of polyunsaturated fatty acids in the prevention of cardiovascular diseases

Cardiovascular diseases are one of the most important problems of modern medicine. They are associated with a large number of health care visits, hospitalizations and mortality. Prevention of atherosclerosis is one of the most effective strategies and should start as early as possible. Correction of lipid metabolism disorders is associated with definite clinical successes, both in primary prevention and in the prevention of complications of many cardiovascular diseases. A growing body of evidence suggests a multifaceted role for polyunsaturated fatty acids. They demonstrate a variety of functions in inflammation, both participating directly in a number of cellular processes and acting as a precursor for subsequent biosynthesis of lipid mediators. Extensive clinical data also support the importance of polyunsaturated fatty acids, but all questions have not been answered to date, indicating the need for further research.

Effect of n-3 (Omega-3) Polyunsaturated Fatty Acid Supplementation on Metabolic and Inflammatory Biomarkers and Body Weight in Patients with Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of RCTs

Beneficial effects of n-3 fatty acids on metabolic biomarkers in patients with type 2 diabetes (T2DM) has been reported. The objectives of this current research were to investigate the effects of n-3 supplementation on metabolic factors, weight, and body mass index (BMI) in patients with type 2 diabetes mellitus (T2DM), using a meta-analysis of randomized, controlled trials (RCTs). Online databases PubMed, Embase, Web of Science, and Science Direct were searched until 2021 to identify eligible articles. Thirty trials were included. The results showed that n-3 consumption can significantly reduce glycemic factors including fasting blood sugar (FBS) (−0.36 (−0.71 to −0.01)), glycated hemoglobulin (HbA1c) (−0.74 (−1.13 to −0.35)), and homeostatic model assessment of insulin resistance (HOMA.IR) (−0.58 (−1.13 to −0.03)). Furthermore, significant improvement in lipid profile including triglycerides (TG) (−0.27 (−0.37 to −0.18)), total cholesterol (−0.60 (−0.88 to −0.32)), low density lipoprotein (LDL) (−0.54 (−0.85 to −0.23)), and high-density lipoprotein (HDL) (0.60 (0.23 to 0.96)) levels were found in the present meta-analysis. The reduction in the inflammatory marker’s tumor necrosis factor-alpha (TNF-α) (−0.13 (−0.75 to 0.48)) and c-reactive protein (CRP) (−0.72 (−1.70 to 0.27)), as well as weight (−0.09 (−0.24 to 0.07)) and BMI (−0.13 (−0.29 to 0.02)) were not statistically significant. Furthermore, the findings revealed that the optimal dose and duration of n-3 consumption for patients with T2DM is 1000–2000 mg/d for more than 8 weeks. The present meta-analysis and review reveals that n-3 supplementation can improve glycemic factors and lipid profile in patients with T2DM. Furthermore, n-3 supplementation may provide beneficial effects on inflammatory markers and body weight if used at the appropriate dose and duration.

Aspirin and omega-3 polyunsaturated fatty acid use and their interaction in cardiovascular diseases and colorectal adenomas

Aspirin (acetylsalicylic acid, ASA) is inexpensive and is established in preventing cardiovascular disease (CVD) and colorectal adenomas. Omega-3 (n3) polyunsaturated fatty acids (PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have also shown benefit in preventing CVD. The combination could be an effective preventative measure in patients with such diseases. ASA and n3 PUFA reduced the risk of CVD in ASA-resistant or diabetic patients. EPA- and DHA-deficient patients also benefited the most from n3 PUFA supplementation. Synergistic effects between ASA and EPA and DHA are 'V-shaped' such that optimal ASA efficacy is dependent on EPA and DHA concentrations in blood. In colorectal adenomas, ASA (300 mg/d) and EPA reduced adenoma burden in a location- and subtype-specific manner. Low doses of ASA (75-100 mg/d) were used in CVD prevention; however, ultra-low doses (30 mg/d) can also reduce thrombosis. EPA-to-DHA ratio is also important with regard to efficacy. DHA is more effective in reducing blood pressure and modulating systemic inflammation; however, high-dose EPA can lower CVD events in high-risk individuals. Although current literature has yet to examine ASA and DHA in preventing CVD, such combination warrants further investigation. To increase adherence to ASA and n3 PUFA supplementation, combination dosage form may be required to improve outcomes.

Beneficial Effects of a Specially Designed Home Meal Replacement on Cardiometabolic Parameters in Individuals with Obesity: Preliminary Results of a Randomized Controlled Clinical Trial

We aimed to investigate if a home meal replacement (HMR), designed with a low ω-6/ω-3 fatty acid ratio, improves cardiometabolic parameters, including metabolic syndrome (MetS) in obese individuals. We conducted a monocentric, controlled, randomized crossover trial. The HMR contains higher protein and fat content, lower carbohydrate content, and a lower ω6FA/ω3FA ratio than the regular diet. Sixty-four participants were randomized into two groups and switched to the other group following a 4-week intervention. While subjects in the HMR group were provided three HMRs daily, those in the control group were requested to maintain their regular dietary pattern. We conducted paired t-tests, repeated measures analysis of variance, and McNemar tests before and after the intervention. Body mass index (BMI) and weight were lower in the HMR group after adjusting for age, sex, and total energy intake and significantly changed in the between-group differences. The waist circumference, systolic blood pressure, triglycerides, triglyceride–glucose index, and triglyceride to high-density lipoprotein cholesterol ratio were reduced in the HMR group (all p < 0.05). The percentage of subjects with MetS significantly decreased from 39.1% at baseline to 28.1% post-intervention (p = 0.035). Using the HMR for 4 weeks reduced the BMI, weight, and MetS prevalence in individuals with obesity. This trial was registered at clinicaltrials.gov (NCT04552574).

Omega-3 polyunsaturated fatty acids and hypertension: a review of vasodilatory mechanisms of docosahexaenoic acid and eicosapentaenoic acid

Hypertension is often characterised by impaired vasodilation involving dysfunction of multiple vasodilatory mechanisms. ω-3 polyunsaturated fatty acids (PUFAs), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) can reduce blood pressure and vasodilation. In the endothelium, DHA and EPA improve function including increased NO bioavailability. However, animal studies show that DHA- and EPA-mediated vasodilation persists after endothelial removal, indicating a role for vascular smooth muscle cells (VSMCs). The vasodilatory effects of ω-3 PUFAs on VSMCs are mediated via opening of large conductance calcium-activated potassium channels (BK_Ca ), ATP-sensitive potassium channels (K_ATP ) and possibly members of the K_v 7 family of voltage-activated potassium channels, resulting in hyperpolarisation and relaxation. ω-3 PUFA actions on BK_Ca and voltage-gated ion channels involve electrostatic interactions that are dependent on the polyunsaturated acyl tail, cis-geometry of these double bonds and negative charge of the carboxyl headgroup. This suggests structural manipulation of ω-3 PUFA could generate novel, targeted, therapeutic leads.

Omega-3 polyunsaturated fatty acids focusing on eicosapentaenoic acid and docosahexaenoic acid in the prevention of cardiovascular diseases: a review of the state-of-the-art

INTRODUCTION

: An epidemiological study of Greenlandic Inuit suggested the importance of omega-3 polyunsaturated fatty acids (PUFAs) in preventing ischemic heart disease. After this landmark study, large-scale epidemiological studies have examined the benefits of omega-3 PUFAs in the prevention of cardiovascular diseases.

AREAS COVERED

: This article reviews studies on omega-3 PUFAs, and identifies issues relevant to cardiovascular risk.

EXPERT OPINION

: Recent studies have focused on the anti-inflammatory effects of omega-3 PUFAs and specialized pro-resolving mediators. High-purity eicosapentaenoic acid (EPA) ethyl ester and EPA/docosahexaenoic acid (DHA) preparations have been developed primarily for the treatment of hypertriglyceridemia. Various trials on the cardiovascular protective effects of omega-3 PUFAs have been reported, but the results have not been consistent. Some issues of the trials have been suggested, such as using low-dose omega-3 PUFAs and not including hypertriglyceridemia in subject selection criteria. REDUCE-IT study that used a high dose of high-purity EPA preparation showed a relative reduction in cardiovascular events, but, the STRENGTH study that used a high dose of EPA/DHA preparation did not support this benefit. This article reviews the roles of omega-3 PUFAs in cardiovascular diseases, including progress in understanding the molecular mechanisms and recent large-scale clinical trials.

Effect of omega-3 polyunsaturated fatty acids in modulation of vascular tone under physiological and pathological conditions

Omega-3 polyunsaturated fatty acids (n-3 PUFAs), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are mainly found in marine fish oils and commercially available fish oil supplements. Several studies have documented that n-3 PUFAs can reduce the risk of cardiovascular diseases through anti-inflammatory, anti-thrombotic, and anti-atherosclerotic properties. Notably, regulation of vascular tone is one of the most important bases of cardiovascular health and especially for maintaining blood pressure within optimal physiological ranges. Recent clinical and animal studies indicate an association between n-3 PUFAs and vascular functions. In this regard, many clinical trials and basic experimental studies have been conducted so far to investigate the influence of n-3 PUFAs on vascular tone. In this review, we have summarized the results obtained from both clinical and basic studies that evaluated the effect of n-3 PUFAs under physiological and pathological conditions. Moreover, we also focus on verifying the underlying basic molecular mechanism of n-3 PUFAs on the vascular system.

Impact of Lifestyles (Diet and Exercise) on Vascular Health: Oxidative Stress and Endothelial Function

Healthy lifestyle and diet are associated with significant reduction in risk of obesity, type 2 diabetes, and cardiovascular diseases. Oxidative stress and the imbalance between prooxidants and antioxidants are linked to cardiovascular and metabolic diseases. Changes in antioxidant capacity of the body may lead to oxidative stress and vascular dysfunction. Diet is an important source of antioxidants, while exercise offers many health benefits as well. Recent findings have evidenced that diet and physical factors are correlated to oxidative stress. Diet and physical factors have debatable roles in modulating oxidative stress and effects on the endothelium. Since endothelium and oxidative stress play critical roles in cardiovascular and metabolic diseases, dietary and physical factors could have significant implications on prevention of the diseases. This review is aimed at summarizing the current knowledge on the impact of diet manipulation and physical factors on endothelium and oxidative stress, focusing on cardiovascular and metabolic diseases. We discuss the friend-and-foe role of dietary modification (including different diet styles, calorie restriction, and nutrient supplementation) on endothelium and oxidative stress, as well as the potential benefits and concerns of physical activity and exercise on endothelium and oxidative stress. A fine balance between oxidative stress and antioxidants is important for normal functions in the cells and interfering with this balance may lead to unfavorable effects. Further studies are needed to identify the best diet composition and exercise intensity.

Omega-3 polyunsaturated fatty acid supplementation versus placebo on vascular health, glycaemic control, and metabolic parameters in people with type 1 diabetes: a randomised controlled preliminary trial

Background

The role of omega-3 polyunsaturated fatty acids (n-3PUFA), and the potential impact of n-3PUFA supplementation, in the treatment and management of type 1 diabetes (T1D) remains unclear and controversial. Therefore, this study aimed to examine the efficacy of daily high-dose-bolus n-3PUFA supplementation on vascular health, glycaemic control, and metabolic parameters in subjects with T1D.

Methods

Twenty-seven adults with T1D were recruited to a 6-month randomised, double-blind, placebo-controlled trial. Subjects received either 3.3 g/day of encapsulated n-3PUFA or encapsulated 3.0 g/day corn oil placebo (PLA) for 6-months, with follow-up at 9-months after 3-month washout. Erythrocyte fatty acid composition was determined via gas chromatography. Endpoints included inflammation-associated endothelial biomarkers (vascular cell adhesion molecule-1 [VCAM-1], intercellular adhesion molecule-1 [ICAM-1], E-selectin, P-selectin, pentraxin-3, vascular endothelial growth factor [VEGF]), and their mediator tumor necrosis factor alpha [TNFα] analysed via immunoassay, vascular structure (carotid intima-media thickness [CIMT]) and function (brachial artery flow mediated dilation [FMD]) determined via ultrasound technique, blood pressure, glycosylated haemoglobin (HbA1c), fasting plasma glucose (FPG), and postprandial metabolism.

Results

Twenty subjects completed the trial in full. In the n-3PUFA group, the mean ± SD baseline n-3PUFA index of 4.93 ± 0.94% increased to 7.67 ± 1.86% (P < 0.001) after 3-months, and 8.29 ± 1.45% (P < 0.001) after 6-months. Total exposure to n-3PUFA over the 6-months (area under the curve) was 14.27 ± 3.05% per month under n-3PUFA, and 9.11 ± 2.74% per month under PLA (P < 0.001). VCAM-1, ICAM-1, E-selectin, P-selectin, pentraxin-3, VEGF, TNFα, CIMT, FMD, blood pressure, HbA1c, FPG, and postprandial metabolism did not differ between or within groups after treatment (P > 0.05).

Conclusions

This study indicates that daily high-dose-bolus of n-3PUFA supplementation for 6-months does not improve vascular health, glucose homeostasis, or metabolic parameters in subjects with T1D. The findings from this preliminary RCT do not support the use of therapeutic n-3PUFA supplementation in the treatment and management of T1D and its associated complications.

Trial Registration ISRCTN, ISRCTN40811115. Registered 27 June 2017, http://www.isrctn.com/ISRCTN40811115.

Effects of n-3 PUFA on endothelial function in patients with peripheral arterial disease: a randomised, placebo-controlled, double-blind trial

As only limited evidence is available for potential benefits of n-3 PUFA supplementation in patients with peripheral arterial disease (PAD), we studied the effects of 4 g n-3 PUFA on endothelial function and inflammatory markers. Seventy patients with stable PAD classified as Rutherford stage 2 or 3 and good control of cardiovascular factors were randomised to receive either 4 g n-3 PUFA or placebo daily for 3 months in a double-blind fashion. Primary endpoint was endothelial function assessed by flow-mediated vasodilation (FMD). In addition, ankle-brachial index, maximum and pain-free walking distances were determined. Lipid parameters including the omega-3 index reflecting n-3 PUFA intake as well as pro-inflammatory, endothelial and platelet activation markers were measured over the same time interval. After 3 months of treatment with 4 g n-3 PUFA daily, a significant improvement of FMD was observed compared with placebo (n-3 PUFA, median Δ 3·7 (interquartile range (IQR) -1·8, 7·1) % v. placebo, Δ -0·5 (IQR -6·5, 3·0) %, P = 0·01 between the groups). After a 3-month washout period, this benefit was not sustained (n-3 PUFA, median Δ 0·6 (IQR -2·2, 5·6) % v. placebo, Δ -0·9 (IQR -6·6, 6·7) %, P = 0·20). In response to n-3 PUFA, an improvement of lipid parameters with a pronounced increase in the omega-3 index was seen. No changes were found for other parameters. In conclusion, in patients with PAD, 4 g/d n-3 PUFA improved cardiovascular risk in PAD patients, which needs testing in large-scale trials.

Evaluation of the Effect of Fish Oil Alone and in Combination with a Proprietary Chromium Complex on Endothelial Dysfunction, Systemic Inflammation and Lipid Profile in Type 2 Diabetes Mellitus - A Randomized, Double-Blind, Placebo-Controlled Clinical Study

PURPOSE

This study was conducted to evaluate the effectiveness of fish oil alone and with an adjunct, a proprietary chromium complex (PCC), on cardiovascular parameters - endothelial dysfunction, lipid profile, systemic inflammation and glycosylated hemoglobin - in a 12-week randomized, double-blind, placebo-controlled clinical study in type 2 diabetes mellitus subjects.

PATIENTS AND METHODS

In this randomized, double-blind, parallel group study, 59 subjects in three groups completed the study: Group A, fish oil 2000 mg; Group B, fish oil 2000 mg + PCC 10 mg (200 µg of Cr³⁺); and Group C, fish oil 2000 mg + PCC 20 mg (400 µg of Cr³⁺) daily for 12 weeks (2000 mg of fish oil contained 600 mg of eicosapentaenoic acid [EPA] and 400 mg of docosahexaenoic acid [DHA], the omega-3 fatty acids). Endothelial function, by estimating reflection index (RI), biomarkers of oxidative stress (nitric oxide [NO], malondialdehyde [MDA], glutathione [GSH]) and inflammatory biomarkers (high-sensitivity C-reactive protein [hsCRP], intercellular adhesion molecule-1 [ICAM-1], vascular cell adhesion molecule-1 [VCAM-1], endothelin-1) were evaluated at baseline, and 4 and 12 weeks. Lipid profile, platelet aggregation and glycosylated hemoglobin [HbA1c) were tested at baseline and 12 weeks. Any reported adverse drug reactions were recorded. Statistical analysis was performed using GraphPad Prism 8.

RESULTS

The present study shows that fish oil by itself, at a dose of 2000 mg (600 mg of EPA + 400 mg of DHA) per day, led to significant, but only modest, improvement in cardiovascular parameters (RI from -2.38±0.75 to -3.92±0.60, MDA from 3.77±0.16 to 3.74±0.16 nM/mL, NO from 30.60±3.18 to 32.12±3.40 µM/L, GSH from 568.93±5.91 to 583.95±6.53 µM/L; p≤0.0001), including triglyceride levels. However, when PCC was added to fish oil, especially at the 20 mg dose, there were highly significant improvements in all the parameters tested (RI from -2.04±0.79 to -8.73±1.36, MDA from 3.67±0.39 to 2.89±0.34 nM/mL, NO from 28.98±2.93 to 40.01±2.53 µM/L, GSH from 553.82±8.18 to 677.99±10.19 µM/L; p≤0.0001), including the lipid profile. It is noteworthy that the triglycerides were decreased significantly by addition of 20 mg of PCC although the dose of fish oil was only 2 g/day and the baseline triglyceride levels were only about 200 mg/dL. Fish oil alone did not significantly decrease the HbA1c, whereas the addition of 20 mg of PCC did.

CONCLUSION

Addition of PCC, especially at 20 mg dose, significantly improves the efficacy of fish oil in addressing cardiovascular risk factors compared to fish oil given alone.

Modulation of endothelial cell responses and vascular function by dietary fatty acids

Healthy and functional endothelial cells play important roles in maintaining vascular homeostasis, whereas endothelial dysfunction initiates and exacerbates vascular disease progression. Interventional studies with dietary fatty acids have shown that these molecules have varying effects on vascular function. It is hypothesized that the actions of dietary fatty acids on vascular function may be mediated in part through endothelial cells. This review summarizes the results of studies that have examined the acute and chronic effects of dietary fatty acids on endothelial function and vascular properties in humans, as well as the potential mechanisms by which n-3 polyunsaturated fatty acids regulate endothelial function. Altogether, this article provides an extensive review of how fatty acids contribute to vascular function through their ability to modulate endothelial cells and discusses relationships between dietary fatty acids and endothelial cells in the context of vascular dysfunction.

Addition of marine omega-3 fatty acids to statins in familial hypercholesterolemia does not affect in vivo or in vitro endothelial function

BACKGROUND

Prestatin trials reported positive effects of omega-3 polyunsaturated fatty acids (n-3 PUFA) in cardiovascular disease, whereas recent studies and meta-analyses have not reproduced these results. The effect of n-3 PUFA in patients with familial hypercholesterolemia (FH), a group with particularly high risk of cardiovascular disease, is not well established.

OBJECTIVE

We investigated the effect of n-3 PUFA in the early stage of atherosclerosis in FH patients by evaluating in vivo (peripheral arterial tonometry [PAT]) and in vitro (plasma asymmetric dimethylarginine and E-selectin) endothelial function.

METHODS

This was a double-blind, placebo-controlled cross-over study with 34 FH patients on statin treatment (mean age 46.6 years). In random order, all individuals were treated for 3 months with high-dose n-3 PUFA (2 g, ×2) and 3 months placebo (olive oil, 2 g ×2), separated by a 3-month washout period. Anthropometric data, blood samples, and PAT were collected at 4 time points.

RESULTS

There were no significant changes in reactive hyperemia index measured by PAT after n-3 PUFA compared with placebo, median reactive hyperemia index after n-3 PUFA was 1.98 and after placebo 1.96 (P = .51). No significant changes were detected in the soluble endothelial marker asymmetric dimethylarginine (in 2 different assays) when comparing n-3 PUFA and placebo (P = .92 and .14, respectively). Finally, the level of E-selectin did not change significantly during the trial (P = .26).

CONCLUSION

Addition of n-3 PUFA to standard lipid-lowering treatment in genetically verified FH patients did not affect the in vivo endothelial function or soluble endothelial markers.

The Use of Nutraceuticals to Counteract Atherosclerosis: The Role of the Notch Pathway

Despite the currently available pharmacotherapies, today, thirty percent of worldwide deaths are due to cardiovascular diseases (CVDs), whose primary cause is atherosclerosis, an inflammatory disorder characterized by the buildup of lipid deposits on the inside of arteries. Multiple cellular signaling pathways have been shown to be involved in the processes underlying atherosclerosis, and evidence has been accumulating for the crucial role of Notch receptors in regulating the functions of the diverse cell types involved in atherosclerosis onset and progression. Several classes of nutraceuticals have potential benefits for the prevention and treatment of atherosclerosis and CVDs, some of which could in part be due to their ability to modulate the Notch pathway. In this review, we summarize the current state of knowledge on the role of Notch in vascular health and its modulation by nutraceuticals for the prevention of atherosclerosis and/or treatment of related CVDs.

Clinical Advances in Immunonutrition and Atherosclerosis: A Review

Atherosclerosis is a chronic low-grade inflammatory disease that affects large and medium-sized arteries and is considered to be a major underlying cause of cardiovascular disease (CVD). The high risk of mortality by atherosclerosis has led to the development of new strategies for disease prevention and management, including immunonutrition. Plant-based dietary patterns, functional foods, dietary supplements, and bioactive compounds such as the Mediterranean Diet, berries, polyunsaturated fatty acids, ω-3 and ω-6, vitamins E, A, C, and D, coenzyme Q10, as well as phytochemicals including isoflavones, stilbenes, and sterols have been associated with improvement in atheroma plaque at an inflammatory level. However, many of these correlations have been obtained in vitro and in experimental animals' models. On one hand, the present review focuses on the evidence obtained from epidemiological, dietary intervention and supplementation studies in humans supporting the role of immunonutrient supplementation and its effect on anti-inflammatory response in atherosclerotic disease. On the other hand, this review also analyzes the possible molecular mechanisms underlying the protective action of these supplements, which may lead a novel therapeutic approach to prevent or attenuate diet-related disease, such as atherosclerosis.

Acute Endothelial Benefits of Fat Restriction over Carbohydrate Restriction in Type 2 Diabetes Mellitus: Beyond Carbs and Fats

Background: Cardiovascular diseases (CVD) are the major cause of mortality in type 2 diabetes patients (T2DM). The causes are embedded in a complex interplay between excess body fat, insulin resistance and serum lipid anomalies. Endothelial homeostasis is strongly affected by this pathogenic network. Even though metabolic changes and weight loss improve vascular endothelial function, the effect of different dietary approaches is still uncertain for type 2 diabetes patients. Objective: We aimed to compare the acute effects of a hypocaloric very low carbohydrate (VLC) diet versus a hypocaloric low fat (LF) diet on flow mediated dilation (FMD), intrahepatic lipid (IHL) accumulation and visceral adipose tissue as independent risk factors of CVD in T2DM patients. Design: 36 T2DM patients (age 63 ± 8 years, 60% females) were randomly assigned to the VLC diet (4–10% of total energy intake (E)) or to the LF diet (<30% E) for 3 weeks. Endothelial function was assessed by the flow mediated dilation (FMD) method. Adipose tissue depots and IHL were determined by magnetic resonance. Results: Both dietary strategies reduced body weight, body fat content and IHL. Unexpectedly, the LF group experienced significantly greater enhancement of FMD, compared to the VLC group. The FMD showed a positive correlation with protein intake and fat intake in the LF group, while it revealed a negative correlation with protein intake in the VLC diet group. Conclusions: Reduction of total and hepatic adiposity was shown to be successful using either the VLC or LF hypocaloric diets, however, improvements in FMD may be related to the interplay of fat and protein intake.

Influence of Bioactive Nutrients on the Atherosclerotic Process: A Review

The protective effects of a dietary intervention as a useful tool in the prevention of atherosclerosis disease has gained greater attention in recent years. Several epidemiological studies have demonstrated the importance of diet in reducing expensive treatments or possible undesirable side effects. The main aim of this review is to examine the effects of specific nutrients on the development and progression of atherosclerosis in patients with cardiovascular disease. Various mechanisms have been proposed to explain the cardioprotective effect of different nutrients. In this sense, results have shown stabilization of vulnerable atherosclerotic plaques or downregulation of biomarkers related to inflammation through nutrients such as Omega-3 polyunsaturated fatty acids, hydroxytyrosol of extra virgin olive oil, lycopen, phytosterols of plants, or flavonols of fruits and vegetables, among others. The accumulated evidence on the anti-inflammatory effects related to these nutrients is summarized in the present review.

Omega-3 fatty acids in coronary heart disease: Recent updates and future perspectives

Incidence of coronary heart disease (CHD) increases worldwide with varying etiological factors. In addition to the control of risk factors, dietary modification has been recommended to reduce the prevalence. Omega-3 (ω-3) fatty acids (FAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), of fish oil are beneficial for the prevention of CHD. The effect can be ascribed to anti-inflammatory, vasodilating, antiarrhythmic, antihypertensive activities and lowering of triacyl glycerol level. The American Heart Association advises two fish meals per week in subjects without CHD or supplementation of 1 g of EPA plus DHA per day in subjects with CHD. Despite the beneficial effects of EPA/DHA reported in some of the clinical trials, results of many others were inconsistent that can be ascribed to short duration of studies, low doses of ω-3 FAs, variations in the EPA:DHA ratio, selection of patients with different risk factors or interaction of ω-3 FAs with drugs used in the therapy. Therefore, well designed clinical trials in various populations are warranted. This article discusses the current situation and future prospective of ω-3 FAs in CHD.