Omega-3 fatty acids for cardioprotection

Dietary Application of the Microalga Lobosphaera incisa P127 Reduces Severity of Intestinal Inflammation, Modulates Gut-Associated Gene Expression, and Microbiome in the Zebrafish Model of IBD

SCOPE

Microalgae are an emerging nutritional resource of biomolecules with potential to alleviate gut inflammation. The study explores the anti-inflammatory and immunomodulatory potential of the microalga Lobosphaera incisa P127, which accumulates a rare omega-6 LC-PUFA dihomo-ɣ-linolenic acid (DGLA) under nitrogen starvation. The therapeutic potential of dietary supplementation with P127 is investigated in the zebrafish model of IBD (TNBS-induced colitis).

METHODS AND RESULTS

Guts are sampled from zebrafish fed experimental diets for 4 weeks, before and 24 h after TNBS challenge. Diets containing 15% non-starved (Ns) and 7.5% and 15% N-starved (St) algal biomass significantly attenuate the severity of gut injury and goblet cell depletion. In contrast, diets containing 7.5% Ns and DGLA ethyl ester have no effect on gut condition. Fish fed 15% St, high-DGLA biomass, have the fewest individuals with pathological alterations in the gut. Dietary inclusion of Ns and St distinctly modulates gut-associated expression of the immune and inflammatory genes. Fish fed 15% Ns biomass display a coordinated boost in immune gene expression and show major changes in the gut microbiome prior challenge.

CONCLUSION

Dietary inclusion of L. incisa biomass at two physiological states, ameliorates TNBS-induced gut inflammation, suggesting the synergistic beneficial effects of biomass components not limited to DGLA.

The Quest for Neurodegenerative Disease Treatment-Focusing on Alzheimer's Disease Personalised Diets

Dementia represents a clinical syndrome characterised by progressive decline in memory, language, visuospatial and executive function, personality, and behaviour, causing loss of abilities to perform instrumental or essential activities of daily living. The most common cause of dementia is Alzheimer's disease (AD), which accounts for up to 80% of all dementia cases. Despite that extensive studies regarding the etiology and risk factors have been performed in recent decades, and how the current knowledge about AD pathophysiology significantly improved with the recent advances in science and technology, little is still known about its treatment options. In this controverted context, a nutritional approach could be a promising way to formulate improved AD management strategies and to further analyse possible treatment strategy options based on personalised diets, as Nutritional Psychiatry is currently gaining relevance in neuropsychiatric disease treatment. Based on the current knowledge of AD pathophysiology, as well as based on the repeatedly documented anti-inflammatory and antioxidant potential of different functional foods, we aimed to find, describe, and correlate several dietary compounds that could be useful in formulating a nutritional approach in AD management. We performed a screening for relevant studies on the main scientific databases using keywords such as "Alzheimer's disease", "dementia", "treatment", "medication", "treatment alternatives", "vitamin E", "nutrition", "selenium", "Ginkgo biloba", "antioxidants", "medicinal plants", and "traditional medicine" in combinations. Results: nutrients could be a key component in the physiologic and anatomic development of the brain. Several nutrients have been studied in the pursuit of the mechanism triggered by the pathology of AD: vitamin D, fatty acids, selenium, as well as neuroprotective plant extracts (i.e., Ginkgo biloba, Panax ginseng, Curcuma longa), suggesting that the nutritional patterns could modulate the cognitive status and provide neuroprotection. The multifactorial origin of AD development and progression could suggest that nutrition could greatly contribute to the complex pathological picture. The identification of adequate nutritional interventions and the not yet fully understood nutrient activity in AD could be the next steps in finding several innovative treatment options for neurodegenerative disorders.

Pharmacokinetics of Icosapent Ethyl: An Open-Label, Multiple Oral Dose, Parallel Design Study in Healthy Chinese Subjects

Icosapent ethyl (IPE) is a high-purity prescription form of eicosapentaenoic acid (EPA) ethyl ester that has been approved to lower triglyceride levels in adult patients with severe (≥500 mg/dL) hypertriglyceridemia. Before this study, there were no pharmacokinetics (PK) or safety data in Chinese patients after receiving IPE. The purpose of this study was to evaluate the PK of EPA in plasma and red blood cells and safety after oral administration of IPE capsules for 28 consecutive days in healthy Chinese subjects. It was a randomized, open-label, parallel-designed multiple-dose, phase I study. Twenty-four subjects were enrolled and randomly assigned to 2 groups, including 6 men and 6 women in each group. Group A received IPE 2.0 g/day (1×1 g twice daily), and group B received IPE 4.0 g/day (2×1 g twice daily) with dosing after standard meals for 28 days. During the treatment period, PK samples were collected from all subjects before the morning dose on days 1, 14, 26, and 28. Following completion of the last study drug administration in the morning on day 28, an 18-day posttreatment PK sample collection period was followed. Twenty-four eligible subjects were enrolled in this study, and 1 subject withdrew from the study. The main PK parameters (baseline-corrected maximum observed plasma concentration and area under the plasma concentration-time curve during a dosing interval) of plasma total EPA, RBC EPA, and plasma unesterified EPA increased with dose. Chinese healthy subjects who took IPE capsules orally in the dose range of 2.0 to 4.0 g/day for 28 consecutive days were safe and tolerable.

Properties of Polyunsaturated Fatty Acids in Primary and Secondary Prevention of Cardiovascular Diseases in the View of Patients (Silesia, Poland)

BACKGROUND

Cardiovascular diseases are a major cause of morbidity and mortality in Europe. Lifestyle plays an important role in the primary and secondary prevention of cardiovascular diseases, apart from pharmacotherapy and diagnostics. Numerous studies confirm that the type and quality of fat consumed in the diet have a huge impact on the risk of cardiovascular diseases. Reducing the risk of cardiovascular disease can be helped by minimizing the proportion of saturated fatty acids in the diet and replacing them with polyunsaturated fatty acids. These acids and, above all, their long-chain forms have a positive effect on health.

AIM

This study aims to assess the awareness of the properties of polyunsaturated fatty acids in the primary and secondary prevention of cardiovascular diseases in the opinions of patients of the Cardiology Department of the Racibórz Medical Center.

MATERIAL AND METHODS

The analysis included 302 patients (113 women and 189 men) hospitalized in the Cardiology Department. The research method was the authors' questionnaire consisting of the patients' record and thirty closed questions. To answer the research questions posed and test the hypotheses, statistical analyses were carried out using the IBM SPSS Statistics version 25 package.

RESULTS

Among the respondents, the least frequently used healthy eating habit was the infrequent eating of fried foods. A total of 18.2% of respondents had such a habit. The most commonly used healthy eating habit was checking the fat content in products, which was performed by 67.2% of respondents. Among the respondents, 58.3% said that butter and margarine increase serum cholesterol.

CONCLUSIONS

The analysis of the data shows that the place of residence, education, sex, and reason for hospitalization of the respondents did not affect the frequency of healthy eating habits. In addition, the subjects had a low amount of healthy eating habits.

Lessons learned from two clinical trials on nutritional supplements to reduce aggressive behaviour

BACKGROUND

Setting up and conducting a randomised controlled trial (RCT) has many challenges-particularly trials that include vulnerable individuals with behavioural problems or who reside in facilities that focus on care as opposed to research. These populations are underrepresented in RCTs.

APPROACH

In our paper, we describe the challenges and practical lessons learned from two RCTs in two care settings involving long-stay psychiatric inpatients and people with intellectual disabilities. We describe five main difficulties and how these were overcome: (1) multisite setting, (2) inclusion of vulnerable participants, (3) nutritional supplements and placebos, (4) assessment of behavioural outcomes, and (5) collecting bio samples.

CONCLUSIONS

By sharing these practical experiences, we hope to inform other researchers how to optimally design their trials, while avoiding and minimising the difficulties that we encountered, and to facilitate the implementation of a trial. Both trials were registered in the Clinical Trials Register (RCT A: NCT02498106; RCT B: NCT03212092).

The fatty acid composition of serum phospholipids in adolescents is associated with body composition in early adulthoods: an eight-year follow-up study

The fatty acid composition is associated with obesity. Omega 3 polyunsaturated fatty acid (PUFA) could have a beneficial role in the prevention and treatment of many disorders, including cardiometabolic diseases. A cohort of 84 men and 131 women were examined in adolescence and after 8 years. Body weight (BW) and fat mass (FM) were measured. The composition of fatty acids (FAs) of serum phospholipids was assessed using gas chromatography. Statistics: PLS method. Aim: to determine the relationships between FAs in adolescence and FM (explanatory variable 1, EV1) and BW (explanatory variable 2, EV2) in adulthood. In the predictive models, a cluster of FAs in boys explained 47.2 % of EV1 and a cluster of 6 FAs in girls explained 32.3 % of EV1 measured in adulthood. FAs measured in adolescents explained 23.7 % of EV2 in early adults regardless of gender. A significant negative association was found between 18:1n-9c and EV1 in males and EV2 in both genders. We found a significant negative association between 18:2n-6 and 20:0 and both EV1 and EV2. In all analyses, we found a significant negative association of 20:1n-9 and 18:3n-3 with EV1-2 in both genders. A significant positive association was found in 20:3n-6 with EV1 and EV2 in males. 20:4n-6 was positively associated with EV1 in females and EV2 in both genders. A positive association between FM and very long chain n- 6 PUFAs was also observed. It is concluded that serum MUFAs and essential PUFAs in adolescence are associated with lower BW and FM in adulthood.

Antiarrhythmic and Hemodynamic Effects of Omega-3 Polyunsaturated Fatty Acids on Cardiovascular Diseases

This review presents the results of previously performed epidemiological, experimental and clinical studies indicating the use of ω-3 PUFA (polyunsaturated fatty acids) contributes to reduce the risk of developing cardiovascular diseases. Experimental studies have shown ω-3 PUFA are exhibiting antiarrhythmic effects, improving endothelial function, showing an anti- inflammatory effect, affecting the rheological properties of blood, reducing triglyceride concentrations, and increasing the stability of atheromatous plaque. Wide-scale clinical trials have established high efficacy of ω-3 PUFA in primary and secondary prevention of coronary heart disease. It is found to reduce the risk of ventricular arrhythmias and sudden cardiac death. Also, reduces overall mortality and hospitalization rates due to cardiovascular causes in patients with chronic heart failure. Clinical efficacy among cardiovascular diseases of the prescription drugs ω-3 PUFA standardized by qualitative and quantitative compositions to be studied further in a comparison to the other medications with similar make-up.

A critical review on the health benefits of fish consumption and its bioactive constituents

As one of food sources, fish provides sufficient nutrition to human. Diverse nutrients in fish make fish an important nutrient source available easily across the globe. Fish is proven to possess several health benefits, such as anti-oxidation, anti-inflammation, wound healing, neuroprotection, cardioprotection, and hepatoprotection properties. Fish proteins, such as immunoglobins, act as defense agents against viral and bacterial infections and prevent protein-calorie malnutrition. Besides, fish oil constituents, such as polyunsaturated fatty acids (PUFAs), regulate various signaling pathways, such as nuclear factor kappa B pathway, Toll-like receptor pathway, transforming growth factor-β (TGF-β) pathway, and peroxisome proliferators activated receptor (PPAR) pathways. In this review, the literature about health benefits of fish consumption are accumulated from PubMed, Google Scholar, Scopus, and the mechanistic action of health benefits are summarized. Fish consumption at least twice per week as part of a healthy diet is beneficial for a healthy heart. More advances in this field could pose fish as a major nutrients source of foods.

The Effects of Fish Oil on Cardiovascular Diseases: Systematical Evaluation and Recent Advance

Fish oil is rich in unsaturated fatty acids, i.e., eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), both of which are widely distributed in the body such as heart and brain. In vivo and in vitro experiments showed that unsaturated fatty acids may have effects of anti-inflammation, anti-oxidation, protecting vascular endothelial cells, thrombosis inhibition, modifying autonomic nerve function, improving left ventricular remodeling, and regulating blood lipid. Given the relevance to public health, there has been increasing interest in the research of potential cardioprotective effects of fish oil. Accumulated evidence showed that fish oil supplementation may reduce the risk of cardiovascular events, and, in specific, it may have potential benefits in improving the prognosis of patients with hypertension, coronary heart disease, cardiac arrhythmias, or heart failure; however, some studies yielded inconsistent results. In this article, we performed an updated systematical review in order to provide a contemporary understanding with regard to the effects of fish oil on cardiovascular diseases.

Lung Function and Short-Term Ambient Air Pollution Exposure: Differential Impacts of Omega-3 and Omega-6 Fatty Acids

RATIONALE

Exposure to air pollution is associated with adverse respiratory effects. Omega-3 polyunsaturated fatty acids (n-3 FA) appear to attenuate the health effects to air pollution.

OBJECTIVE

This panel study evaluated whether n-3 FA intake and blood levels of omega-6 polyunsaturated fatty acids (n-6 FA) can modulate the associations between respiratory effects and short-term exposure to ambient air pollution in healthy adults.

METHODS

Sixty-two healthy adults were enrolled into either high or low n-3 groups based on n-3 FA intake and erythrocytes n-3 FA concentrations. Low and high n-6 groups were dichotomized on blood n-6 FA levels. Participants underwent 3-5 testing sessions separated by at least seven days. At each session, FVC, FEV1, plasma markers of inflammation (IL-6) and oxidative stress (ox-LDL) were measured. Associations between ambient ozone and fine particulate matter (PM2.5) levels and lung function and blood markers were assessed using mixed-effects models stratified by fatty acids levels.

RESULTS

Average concentrations of ozone (40.8±11.1 ppb) and PM2.5 (10.2±4.1 µg/m3) were below national ambient air quality standards during the study period. FVC was positively associated with ozone at lag0 in the high n-3 group while the association was null in the low n-3 group [for an IQR increase in ozone, 1.8%(95% CI:0.5-3.2) vs. 0.0%(95% CI:-1.4-1.5)]; however, the association shifted to negative at lag4 [-1.9%(95% CI:-3.2- -0.5) vs. 0.2%(95% CI:-1.2-1.5)] and lag5 [-1.2%(95% CI:-2.4-0.0) vs. 0.9%(-0.4-2.3)]. A similar pattern was observed in the low n-6 group compared to the high n-6 group [lag0:1.7%(95% CI:0.3-3.0) vs. 0.5%(95% CI:-0.9-2.0) and lag4:-1.4%(95% CI:-2.8-0.0) vs. -0.5%(95% CI:-1.8-0.9)]. The associations between FEV1 and ozone and between FVC and PM2.5 also followed a similar pattern. Elevated ozone levels were associated with an immediate decrease in ox-LDL in the high n-3 group atlag0 [-12.3%(95% CI:-24.8-0.1)] while no change in the low n-3 group [-7.5%(95% CI: -21.4-6.5)], and a delayed increase in IL-6 in the high n-3 group compared with the low n-3 group [lag4: 66.9%(95% CI:27.9-106.0) vs. 8.9%(95% CI:-31.8-49.6), lag5: 58.2%(95% CI:22.4-94.1) vs. -7.4%(95% CI:-48.8-34.0), and lag6: 45.8%(95% CI:8.7-82.9) vs. -8.5%(95% CI:-49.7-32.6)].

CONCLUSIONS

We observed lag-dependent associations between short-term ambient air pollutants and lung function that were differentially modulated by n-3 and n-6 FAs, suggesting that n-3 and n-6 FAs counteract the respiratory response to low levels of ambient air pollution in healthy adults. Clinical trial registered with ClinicalTrials.gov (NCT02921048).

Heavy metal and metalloid accumulation in wild brown trout (Salmo trutta L., 1758 complex, Osteichthyes: Salmonidae) from a mountain stream in Sardinia by ICP-OES

 This paper reports heavy metal and metalloid accumulation in wild brown trout (Salmo trutta L., 1758 complex) raised in freshwater and uncontaminated Sardinia system (Italy). Metals are widespread pollutants of aquatic systems, and their contamination can originate from anthropogenic activities such as industrial waste, agricultural and domestic environments, and geochemical release. Fish has a relevant position within the human diet; moreover, fishes can accumulate metals, making them a valuable tool as biomarkers for risk assessment studies. The concentration of 22 metals and metalloids after chemical digestion was assessed by inductively coupled plasma-optic emission spectroscopy (ICP-OES) in both the guts and the edible part (EP, muscle + skin) of brown trout. The results, expressed as μg g-1, showed different levels of accumulation in the EP and guts, following the series Cu > Zn > Ba > Al > Sr > Fe > Pb and Fe > Al > Hg > As > Mn > Cu > Ba > B > Zn > Pb, respectively. PCA analysis showed a fairly good correlation between the total lipid and SAFA content and Cd, Hg, and Pb accumulation in the gut. Non-carcinogenic risk assessment, expressed as THQ (target hazard quotient), showed values far below 1 for all metals in muscles, while high As and Hg contamination of the gut draws attention to possible health risks which should be discarded from the fish before consumption. TR (target cancer risk) values showed alarmingly high values for As and Cd when the fish were consumed entirely (gut + EP), while Pb levels were far below the safety levels.

Lipid-modifying effects of krill oil vs fish oil: a network meta-analysis

CONTEXT

Krill oil is a good source of n-3 phospholipids and has greater bioavailability than fish oil, which contains n-3 triglycerides. However, it is unclear whether krill oil affects circulating lipid concentrations more beneficially than fish oil.

OBJECTIVE

A network meta-analysis was conducted to compare the lipid-modifying effects of krill oil and fish oil.

DATA SOURCES

PubMed and Embase databases were searched.

STUDY SELECTION

A total of 64 randomized controlled trials that determined the lipid-modifying effects of krill oil or fish oil were selected.

DATA EXTRACTION

The MetaXL program was used for meta-analysis. A subgroup analysis and a network meta-regression were conducted to investigate the dose-response effect of the n-3 fatty acid content of fish oil and krill oil.

RESULTS

Krill oil was associated with significantly lower triglyceride levels than control supplements (weighted mean difference [WMD] -23.26 [95%CI, -38.84 to -7.69]). However, the net differences in triglycerides (WMD -4.07 [95%CI, -15.22 to 7.08]), low-density lipoprotein cholesterol (WMD 3.01 [95%CI, -5.49 to 11.51]), high-density lipoprotein cholesterol (WMD 1.37 [95%CI, -3.73 to 6.48]), and total cholesterol (WMD 1.69 [95%CI, -6.62 to 10.01]) were not significantly different between the krill oil and fish oil groups. One gram of n-3 fatty acids contained in fish oil and krill oil lowered median triglycerides by 8.971 mg/dL (95% credible interval [CrI], 2.27 to 14.04) and 9.838 mg/dL (95%CrI, 0.72 to 19.40), respectively.

CONCLUSIONS

The lipid-modifying effects of krill oil and fish oil do not differ. The reduction in triglycerides depends on the dose of n-3 fatty acids consumed.

DO-HEALTH: Vitamin D3 - Omega-3 - Home exercise - Healthy aging and longevity trial - Design of a multinational clinical trial on healthy aging among European seniors

DO-HEALTH is a multi-center clinical trial among 2157 community-dwelling European men and women age 70 and older. The 2x2x2 randomized-control factorial design trial tested the individual and additive benefit, as well as the cost-effectiveness, of 3 interventions: vitamin D 2000 IU/day, omega-3 fatty acids 1000 mg/day (EPA + DHA, ratio 1:2), and a 30-minute 3 times/week home exercise (strength versus flexibility). Each treatment tested has shown considerable prior promise from mechanistic studies, small clinical trials, or large cohort studies, in the prevention of common age-related chronic diseases, but definitive data are missing. DO-HEALTH will test these interventions in relation to 6 primary endpoints (systolic and diastolic blood pressure, non-vertebral fractures, Short Physical Performance Battery score, the Montreal Cognitive Assessment, and risk of infections), plus several secondary endpoints explored in ancillary studies (i.e. rate of any falls and injurious falls, joint pain, oral health, quality of life, and incident frailty). As the 3 interventions have distinct mechanisms of action for each of the 6 primary endpoints, a maximum benefit is expected for their additive benefit as a "multi-modal" intervention. The trial duration is 3 years with in-person contacts with all participants at 4 clinical visits and by quarterly phone calls. Baseline and follow-up blood samples were collected in all participants to measure changes in 25-hydroxyvitamin D and poly-unsaturated fatty acid concentrations. Our objective was to test interventions that are expected to promote healthy aging and longer life expectancy and that can be easily and safely implemented by older community-dwelling adults.

The Potential Uses of Omega-3 Fatty Acids in Dermatology: A Review

BACKGROUND

A growing interest exists in the relationship between diet and skin disease, with many recent studies identifying a role for omega-3 fatty acids (O3FAs) in various dermatological conditions.

OBJECTIVE

Our objective was to identify the spectrum of uses for O3FA supplementation reported in literature and to evaluate the current level of evidence for its clinical application in skin disease prevention and management.

METHODS

A search was conducted using Ovid MEDLINE for primary literature that examined O3FA intake and skin health. A manual search of reference lists was performed to identify additional articles for inclusion.

RESULTS

A total of 38 studies met eligibility for review, reporting benefits for O3FA supplementation in the treatment of psoriasis, atopic dermatitis, acne, and skin ulcers. Additionally, a reduced incidence of skin cancer and a decrease in the severity of drug-associated mucocutaneous side effects were reported with O3FA supplementation.

CONCLUSION

This review yielded many well-studied benefits of O3FA uses in dermatology. Given its high safety profile, low cost, and ease of supplementation, O3FA is a reasonable supplement that may benefit patients wishing to improve inflammatory skin conditions through diet. Areas of particular clinical interest where supplementation may be valuable include O3FAs for systemic UV photoprotection, as well as adjuvant treatment for acne to reduce both inflammatory lesion count and the severity of mucocutaneous side effects associated with isotretinoin use.

Novel Vibrio spp. Strains Producing Omega-3 Fatty Acids Isolated from Coastal Seawater

Omega-3 long-chain polyunsaturated fatty acids (LC-PUFAs), such as eicosapentaenoic acid (EPA) (20:5n-3) and docosahexaenoic acid (DHA) (22:6n-3), are considered essential for human health. Microorganisms are the primary producers of omega-3 fatty acids in marine ecosystems, representing a sustainable source of these lipids, as an alternative to the fish industry. Some marine bacteria can produce LC-PUFAs de novo via the Polyunsaturated Fatty Acid (Pfa) synthase/ Polyketide Synthase (PKS) pathway, which does not require desaturation and elongation of saturated fatty acids. Cultivation-independent surveys have revealed that the diversity of microorganisms harboring a molecular marker of the pfa gene cluster (i.e., pfaA-KS domain) is high and their potential distribution in marine systems is widespread, from surface seawater to sediments. However, the isolation of PUFA producers from marine waters has been typically restricted to deep or cold environments. Here, we report a phenotypic and genotypic screening for the identification of omega-3 fatty acid producers in free-living bacterial strains isolated from 5, 500, and 1000 m deep coastal seawater from the Bay of Biscay (Spain). We further measured EPA production in pelagic Vibrio sp. strains collected at the three different depths. Vibrio sp. EPA-producers and non-producers were simultaneously isolated from the same water samples and shared a high percentage of identity in their 16S rRNA genes, supporting the view that the pfa gene cluster can be horizontally transferred. Within a cluster of EPA-producers, we found intraspecific variation in the levels of EPA synthesis for isolates harboring different genetic variants of the pfaA-KS domain. The maximum production of EPA was found in a Vibrio sp. strain isolated from a 1000 m depth (average 4.29% ± 1.07 of total fatty acids at 10 °C, without any optimization of culturing conditions).

Fermentation performance and metabolomic analysis of an engineered high-yield PUFA-producing strain of Schizochytrium sp

The ω-3/long-chain polyunsaturated fatty acids (LC-PUFAs) play an important role in human health, but they cannot be synthesized in sufficient amounts by the human body. In a previous study, we obtained an engineered Schizochytrium sp. strain (HX-RS) by exchanging the acyltransferase (AT) gene, and it was able to co-produce docosahexaenoic acid and eicosapentaenoic acid. To investigate the mechanism underlying the increase of PUFA content in HX-RS, the discrepancies of fermentation performance, key enzyme activities and intracellular metabolites between HX-RS and its wild-type parent strain (WTS) were analyzed via fed-batch fermentation in 5-L bioreactors. The results showed that the cell dry weight (CDW) of HX-RS was higher than that of the WTS. Metabolomics combined with multivariate analysis showed that 4-aminobutyric acid, proline and glutamine are potential biomarkers associated with cell growth and lipid accumulation of HX-RS. Additionally, the shift of metabolic flux including a decrease of glyceraldehyde-3-phosphate content, high flux from pyruvate to acetyl-CoA, and a highly active glycolysis pathway were also found to be closely related to the high PUFA yield of the engineered strain. These findings provide new insights into the effects of exogenous AT gene expression on cell proliferation and fatty acid metabolism.

fabH deletion increases DHA production in Escherichia coli expressing Pfa genes

BACKGROUND

Some marine bacteria, such as Moritella marina, produce the nutraceutical docosahexaenoic acid (DHA) thanks to a specific enzymatic complex called Pfa synthase. Escherichia coli heterologously expressing the pfa gene cluster from M. marina also produces DHA. The aim of this study was to find genetic or metabolic conditions to increase DHA production in E. coli.

RESULTS

First, we analysed the effect of the antibiotic cerulenin, showing that DHA production increased twofold. Then, we tested a series of single gene knockout mutations affecting fatty acid biosynthesis, in order to optimize the synthesis of DHA. The most effective mutant, fabH, showed a threefold increase compared to wild type strain. The combination of cerulenin inhibition and fabH deletion rendered a 6.5-fold improvement compared to control strain. Both strategies seem to have the same mechanism of action, in which fatty acid synthesis via the canonical pathway (fab pathway) is affected in its first catalytic step, which allows the substrates to be used by the heterologous pathway to synthesize DHA.

CONCLUSIONS

DHA-producing E. coli strain that carries a fabH gene deletion boosts DHA production by tuning down the competing canonical biosynthesis pathway. Our approach can be used for optimization of DHA production in different organisms.

n-3 PUFA and obesity: from peripheral tissues to the central nervous system

The current paradigms of prevention and treatment are unable to curb obesity rates, which indicates the need to explore alternative therapeutic approaches. Obesity leads to several damages to the body and is an important risk factor for a number of other chronic diseases. Furthermore, despite the first alterations in obesity being observed and reported in peripheral tissues, studies indicate that obesity can also cause brain damage. Obesity leads to a chronic low-grade inflammatory state, and the therapeutic manipulation of inflammation can be explored. In this context, the use of n-3 PUFA (especially in the form of fish oil, rich in EPA and DHA) may be an interesting strategy, as this substance is known by its anti-inflammatory effect and numerous benefits to the body, such as reduction of TAG, cardiac arrhythmias, blood pressure and platelet aggregation, and has shown potential to help treat obesity. Thereby, the aim of this narrative review was to summarise the literature related to n-3 PUFA use in obesity treatment. First, the review provides a brief description of the obesity pathophysiology, including alterations that occur in peripheral tissues and at the central nervous system. In the sequence, we describe what are n-3 PUFA, their sources and their general effects. Finally, we explore the main topic linking obesity and n-3 PUFA. Animal and human studies were included and alterations on the whole organism were described (peripheral tissues and brain).

Omega-3 Polyunsaturated Fatty Acids and Cardiovascular Health: A Comprehensive Review

The potential cardiovascular (CV) disease (CVD) benefits of Omega-3 Polyunsaturated Fatty Acids (OM3) have been intensely studied and debated for decades. Initial trials were performed in patients with low use of maximal medical therapy for CVD, and reported significant mortality benefits with the use of 1 g/day OM3 intervention following myocardial infarction (MI). More recent studies, including cohorts of patients receiving modern guideline directed medical therapy for CVD, have often not shown similar benefits with OM3 use. We conducted a literature review using PubMed, professional society guidelines, specific journal databases including New England Journal of Medicine and Journal of the American College of Cardiology from January 1, 2007 to December 31, 2017. References from selected articles were also reviewed, as well as key articles outside of the selected time-frame for their important findings or historical perspectives. Currently, there are no Class I recommendations from the American Heart Association (AHA) for the use of OM3, however, considering the safety of this therapy and beneficial findings of some modern studies (including patients with current maximal medical therapy for CVD), the AHA has recently expanded their list of Class II recommendations, in which treatment with OM3 for CVD benefit is reasonable. This review discusses the current state of the evidence, summarizes current professional recommendations, and provides recommendations for future research.

Immunomodulatory Activity of Docosahexenoic Acid on RAW264.7 Cells Activation through GPR120-Mediated Signaling Pathway

In this study, we elucidated the immunomodulatory activity of docosahexaenoic acid (DHA) on protein expression in RAW264.7 cells and its molecular mechanism. The results showed that the proliferation index of RAW264.7 cells at 48 h was about 173.03 ± 7.82% after the treatment of 2.4 μM DHA. DHA could activate RAW264.7 cells by the G-protein coupled cell membrane receptor GPR120-C-Raf- mitogen-activated protein kinases (MAPKs)-nuclear factor κB (NF-κB) p65 pathway. In addition, 2.4 μM of DHA could significantly increase (P < 0.01) the mRNA and protein expression of inducible nitric oxide synthase (iNOS), which is consistent with the result of the NO release. ELISA results revealed that DHA could enhance the protein expression of cytokines IL-1β, IL-6, IL-10, IL-12, TNF-α, IFN-γ, and TGF-β. These results indicated that the immunomodulatory mechanism of RAW264.7 cells by DHA was associated with the release of NO and cytokines by stimulating the GPR120, C-Raf, and MAPKs to the NF-κB p65 pathway.

Potential Use of Tuna (Thunnus albacares) by-product: Production of Antioxidant Peptides and Recovery of Unsaturated Fatty Acids from Tuna Head

Tuna by-products were subjected to enzymatic hydrolysis with Alcalase (enzyme to substrate ratio 1 : 200 w/w; 60 °C; pH 6.5, 120 min) rendering a tuna protein hydrolysate (TPH) with 9.24 % degree of hydrolysis (DH). The antioxidant capacity of TPH determined by the methods of ferric reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) were similar and 10 times lower than the result obtained by oxygen radical absorbance capacity (ORAC). The total amino acid profile indicated that 42.15 % are composed of hydrophobic amino acids and 7.7 % of aromatics, with leucine being found in the highest quantity (17.85 %). The fatty acid profile of the oil recovered by centrifugation of the TPH – as determined by a gas chromatograph – was characterized by a high percentage of polyunsaturated fatty acids (PUFAs) (39.06 %), mainly represented by the fatty acids ω3, docosahexaenoic acid (27.15 %) and eicosapentaenoic acid (6.05 %). The simultaneous recovery of unsaturated fatty acids and antioxidant peptides can add value to tuna by-products, assisting in the efficient management of fishing industry waste.

EPA Prevents the Development of Abdominal Aortic Aneurysms through Gpr-120/Ffar-4

Abdominal aortic aneurysms (AAAs), which commonly occur among elderly individuals, are accompanied by a risk of rupture with a high mortality rate. Although eicosapentaenoic acid (EPA) has been reported to prevent AAA formation, the mechanism by which EPA works on vascular smooth muscle cells is unknown. This study aimed to investigate the mechanism by which orally-administered EPA prevents the formation of severe AAAs that develop in Osteoprotegerin (Opg) knockout (KO) mice. In the CaCl₂-induced AAA model, EPA attenuated the enhanced progression of AAAs in Opg-KO mice, including the increase in aortic diameter with destruction of elastic fibers in the media. Immunohistochemical analyses showed that EPA reduced the phosphorylation of transforming growth factor beta-activated kinase-1/Map3k7 (Tak-1) and c-Jun NH2-terminal kinase (JNK), as well as the expression of Matrix metalloproteinase-9 (Mmp-9) in the media of the aorta. In smooth muscle cell cultures, rh-TRAIL-induced activation of the Tak-1-JNK pathway and increase in Mmp-9 expression were inhibited by EPA. Moreover, GW9508, a specific ligand for G-protein coupled receptor (Gpr)-120/Free fatty acid receptor (Ffar)-4, mimicked the effects of EPA. The effects of EPA were abrogated by knockdown of the Gpr-120/Ffar-4 receptor gene. Our data demonstrate that the Trail-Tak-1-JNK-Mmp-9 pathway is responsible for the enhancement of AAAs in Opg-KO mice, and that EPA inhibits the Tak-1-JNK pathway by activating Gpr-120/Ffar-4, which results in the attenuation of AAA development.

Nutraceutical therapies for atherosclerosis

Atherosclerosis is a chronic inflammatory disease affecting large and medium arteries and is considered to be a major underlying cause of cardiovascular disease (CVD). Although the development of pharmacotherapies to treat CVD has contributed to a decline in cardiac mortality in the past few decades, CVD is estimated to be the cause of one-third of deaths globally. Nutraceuticals are natural nutritional compounds that are beneficial for the prevention or treatment of disease and, therefore, are a possible therapeutic avenue for the treatment of atherosclerosis. The purpose of this Review is to highlight potential nutraceuticals for use as antiatherogenic therapies with evidence from in vitro and in vivo studies. Furthermore, the current evidence from observational and randomized clinical studies into the role of nutraceuticals in preventing atherosclerosis in humans will also be discussed.

The effect of n-3 polyunsaturated fatty acids on incidence and severity of oxaliplatin induced peripheral neuropathy: a randomized controlled trial

BACKGROUND

Oxaliplatin induced peripheral neurotoxicity (OXIPN) is the major dose-limiting and long-lasting side effect of oxaliplatin. N-3 PUFAs have neuroprotective property via their effects on voltage-gated ion channels and by reducing the production of proinflammatory cytokines that causes neuropathy. This study was a randomized double blind placebo controlled trial to find the possible advantages of n-3 PUFAs for preventing and reducing the severity of OXIPN in patients with colon cancer.

METHODS

Eligible patients with colon cancer randomly allocated to take n-3 PUFAs pearls, 640 mg t.i.d during chemotherapy with oxaliplatin and one month after the cessation of the treatment or placebo. All patients were evaluated for incidence and severity of OXIPN based on "reduced Total Neuropathy Score" in which clinical and electrophysiological assessments were included.

RESULTS

Seventeen patients (47 %) of the n-3 PUFA supplemented group (n = 36) did not develop PN while it was 11 %(4 patients) in the placebo group (n = 35). There was a significant difference in PN incidence (OR = 0.14, .95 % CI = (0.04 to 0.49), p = 0.002). The difference of OXIPN severity was significant between the two study groups (B = -1.61, 0.95 % CI = (-2.59 to -0.62), p = 0.001).

CONCLUSIONS

N-3 PUFAs may have neuroprotective effect for reducing the incidence and severity of OXIPN. Finding an effective prophylactic or symptomatic therapy for OXIPN would significantly improve the patients' quality of life.

TRIAL REGISTRATION

IRCT201112158397N2.

A Dietary Treatment Improves Cerebral Blood Flow and Brain Connectivity in Aging apoE4 Mice

APOE ε4 (apoE4) polymorphism is the main genetic determinant of sporadic Alzheimer's disease (AD). A dietary approach (Fortasyn) including docosahexaenoic acid, eicosapentaenoic acid, uridine, choline, phospholipids, folic acid, vitamins B12, B6, C, and E, and selenium has been proposed for dietary management of AD. We hypothesize that the diet could inhibit AD-like pathologies in apoE4 mice, specifically cerebrovascular and connectivity impairment. Moreover, we evaluated the diet effect on cerebral blood flow (CBF), functional connectivity (FC), gray/white matter integrity, and postsynaptic density in aging apoE4 mice. At 10–12 months, apoE4 mice did not display prominent pathological differences compared to wild-type (WT) mice. However, 16–18-month-old apoE4 mice revealed reduced CBF and accelerated synaptic loss. The diet increased cortical CBF and amount of synapses and improved white matter integrity and FC in both aging apoE4 and WT mice. We demonstrated that protective mechanisms on vascular and synapse health are enhanced by Fortasyn, independent of apoE genotype. We further showed the efficacy of a multimodal translational approach, including advanced MR neuroimaging, to study dietary intervention on brain structure and function in aging.

Nutrients and contaminants in tissues of five fish species obtained from Shanghai markets: Risk-benefit evaluation from human health perspectives

Shanghai is a Chinese megacity in the Yangtze River Delta area, one of the most polluted coastal areas in China. The inhabitants of Shanghai have very high aquatic product consumption rates. A risk-benefit assessment of the co-ingestion of fish nutrients and contaminants has not previously been performed for Shanghai residents. Samples of five farmed fish species (marine and freshwater) with different feeding habits were collected from Shanghai markets in winter and summer. Fatty acids, protein, mercury, cadmium, lead, copper, polychlorinated biphenyls, hexachlorocyclohexanes, and dichlorodiphenyltrichloroethanes were measured in liver, abdominal fat, and dorsal, abdominal, and tail muscles from fish. Tolerable daily intakes and benefit-risk quotients were calculated to allow the benefits and risks of co-ingesting n-3 long-chain polyunsaturated fatty acids and contaminants to be assessed according to the cancer slope factors and reference doses of selected pollutants. All of the contaminant concentrations in the muscle tissues were much lower than the national maximum limits, but the livers generally contained high Hg concentrations, exceeding the regulatory limit. The organic pollutant and n-3 long-chain polyunsaturated fatty acid concentrations correlated with the lipid contents of the fish tissues, and were higher in carnivorous marine fish than in omnivorous and herbivorous freshwater fish. The tolerable daily intakes, risk-benefit quotients, and current daily aquatic product intakes for residents of large Chinese cities indicated that the muscle tissues of most of the fish analyzed can be consumed regularly without significant contaminant-related risks to health. However, attention should be paid to the potential risks posed by dichlorodiphenyltrichloroethane in large yellow croaker and Hg in tilapia. Based on the results of this study, we encourage people to consume equal portions of marine and freshwater fish.

Effect of consuming novel foods consisting high oleic canola oil, barley β-glucan, and DHA on cardiovascular disease risk in humans: the CONFIDENCE (Canola Oil and Fibre with DHA Enhanced) study - protocol for a randomized controlled trial

Background

Metabolic syndrome (MetS) has been identified as a major contributor to the development of cardiovascular disease (CVD). Current recommendations for dietary management of people with MetS involve quantitative and qualitative modifications of food intake, such as high consumption of vegetables, fruits, and whole grain foods. The results from our previous human trials revealed the potential of the dietary components high-oleic acid canola oil (HOCO)-docosahexaenoic acid (DHA) and high molecular weight barley β-glucan individually in managing CVD risk factors. Foods with a combination of HOCO-DHA and barley β-glucan have never been tested for their effects on CVD risk. The objective is to determine the effects of consuming novel foods HOCO-DHA, and barley β-glucan on managing CVD risk factors in people with MetS.

Methods/Design

We are conducting a randomized, single-blind crossover trial with four treatment phases of 28 days each separated by a 4-week washout interval. Participants (n=35) will be provided with weight-maintaining, healthy balanced diet recommendations according to their energy requirements during the intervention periods. Participants will receive muffins and cookies as treatment foods in a random order and will consume at least one meal per day at the research center under supervision. The four treatments include muffins and cookies consisting of (1) all-purpose flour and HOCO-DHA (50 g/day); (2) barley flour (4.36 g/day of β-glucan) and a blend of sunflower oil, safflower oil, and butter as control oil (50 g/day); (3) barley flour (4.36 g/day of β-glucan) and HOCO-DHA (50 g/day; dosage of DHA would be 3 g/day); and (4) all-purpose flour and control oil (50 g/day). At the beginning and end of each phase, we will evaluate anthropometrics; systolic and diastolic blood pressure; blood lipid profile; low-density lipoprotein subfractions and particle size; 10-year Framingham CVD risk score; inflammatory status; and plasma and red blood cell fatty acid profiles, fecal microbiome, and body composition by dual-energy X-ray absorptiometry.

Conclusion

Cholesterol synthesis will also be studied, using a stable isotope approach. The proposed study will lead to innovation of novel food products, which may result in improvement in the overall cardiovascular health of humans.

Trial registration

Clinical trials.gov identifier: NCT02091583. Date of registration: 12 March 2014.

Whey protein gel composites in the diet of goats increased the omega-3 and omega-6 content of milk fat

Previously, feeding whey protein gels containing polyunsaturated fatty acids (PUFA) reduced their rumen biohydrogenation and increased their concentration in milk fat of Holstein cows. Our objective was to test the efficacy of whey protein isolate (WPI) gels produced in a steam tunnel as a method to alter the fatty acid (FA) composition of the milk lipids. Four primiparous Lamancha goats in midlactation were fed three diets in a 3 × 4 Latin square design. The WPI gels were added to a basal concentrate mix that contained one of three lipid sources: (i) 100% soya bean oil (S) to create (WPI/S), (ii) a 1:1 (wt/wt) mixture of S and linseed (L) oil to create (WPI/SL), or (iii) 100% L to create (WPI/L). Periods were 22 days with the first 10 days used as an adjustment phase followed by a 12-day experimental phase. During the adjustment phase, all goats received a rumen available source of lipid, yellow grease, to provide a baseline for milk FA composition. During the experimental phase, each goat received its assigned WPI. Milk FA concentration of C18:2 n-6 and C18:3 n-3 reached 9.3 and 1.64 g/100 g FA, respectively, when goats were fed WPI/S. Feeding WPI/SL increased the C18:2 n-6 and C18:3 n-3 concentration to 6.22 and 4.36 g/100 g FA, and WPI/L increased C18:2 n-6 and C18:3 n-3 to 3.96 and 6.13 g/100 g FA respectively. The adjusted transfer efficiency (%) of C18:3 n-3 to milk FA decreased significantly as dietary C18:3 n-3 intake increased. Adjusted transfer efficiency for C18:2 n-6 did not change with increasing intake of C18:2 n-6. The WPI gels were effective at reducing rumen biohydrogenation of PUFA; however, we observed a change in the proportion increase of C18:3 n-3 in milk FA suggesting possible regulation of n-3 FA to the lactating caprine mammary gland.

Plasma fatty acid composition in French-Canadian children with non-alcoholic fatty liver disease: Effect of n-3 PUFA supplementation

Non-alcoholic fatty liver disease (NAFLD) represents one of the most common causes of liver disease worldwide. As the NAFLD pathogenesis is associated with diet and lifestyle, the aims of the present work are to assess fatty acid (FA) composition in NAFLD young French-Canadian, to determine whether treatment with n-3 FA improves the plasma FA profile, and to define the time on the effectiveness of n-3 FA supplementation. Baseline characteristics of the NAFLD subjects show increased, anthropometric and biochemical parameters. Their plasma FA composition is characterized by a percent increase in total n-6 FA and a high proportion of saturated and total monounsaturated FA, as well as a decrease in Δ5 and increase in Δ6 desaturases. In conclusion, our results document for the first time the composition of plasma FAs in NAFLD young French Canadian and the efficacy of 3-month supplementation to improve the proportion of n-3 FA in their plasma.

Pharmacological approaches in either intermittent or permanent hypoxia: A tale of two exposures

Hypoxia induces several responses at cardiovascular, pulmonary and reproductive levels, which may lead to chronic diseases. This is relevant in human populations exposed to high altitude (HA), in either chronic continuous (permanent inhabitants) or intermittent fashion (HA workers, tourists and mountaineers). In Chile, it is estimated that 1.000.000 people live at highlands and more than 55.000 work in HA shifts. Initial responses to hypoxia are compensatory and induce activation of cardioprotective mechanisms, such as those seen under intermittent hypobaric (IH) hypoxia, events that could mediate preconditioning. However, whenever hypoxia is prolonged, the chronic activation of cellular responses induces long-lasting modifications that may result in acclimatization or produce maladaptive changes with increase in cardiovascular risk. HA exposure during pregnancy induces hypoxia and oxidative stress, which in turn may promote cellular responses and epigenetic modifications resulting in severe impairment in growth and development. Sadly, this condition is accompanied with an increased fetal and neonatal morbi-mortality. Further, developmental hypoxia may program cardio-pulmonary circulations later in postnatal life, ending in vascular structural and functional alterations with augmented risk on pulmonary and cardiovascular failure. Additionally, permanent HA inhabitants have augmented risk and prevalence of chronic hypoxic pulmonary hypertension, right ventricular hypertrophy and cardiopulmonary remodeling. Similar responses are seen in adults that are intermittently exposed to chronic hypoxia (CH) such as shift workers in HA areas. The mechanisms involved determining the immediate, short and long-lasting effects are still unclear. For several years, the study of the responses to hypoxic insults and pharmacological targets has been the motivation of our group. This review describes some of the mechanisms underlying hypoxic responses and potential therapeutic approaches with antioxidants such as melatonin, ascorbate, omega 3 (Ω3) or compounds that increase the nitric oxide (NO) bioavailability.

Relation of fish oil supplementation to markers of atherothrombotic risk in patients with cardiovascular disease not receiving lipid-lowering therapy

Fish oil supplementation (FOS) is known to have cardiovascular benefits. However, the effects of FOS on thrombosis are incompletely understood. We sought to determine if the use of FOS is associated with lower indices of atherothrombotic risk in patients with suspected coronary artery disease (sCAD). This is a subgroup analysis of consecutive patients with sCAD (n=600) enrolled in the Multi-Analyte, Thrombogenic, and Genetic Markers of Atherosclerosis study. Patients on FOS were compared with patients not on FOS. Lipid profile was determined by vertical density gradient ultracentrifugation (n=520), eicosapentaenoic acid+docosahexaenoic acid was measured by gas chromatography (n=437), and AtherOx testing was performed by immunoassay (n=343). Thromboelastography (n=419), ADP- and collagen-induced platelet aggregation (n=137), and urinary 11-dehydrothromboxane B2 levels (n=259) were performed immediately before elective coronary angiography. In the total population, FOS was associated with higher eicosapentaenoic acid+docosahexaenoic acid content (p<0.001), lower triglycerides (p=0.04), total very low-density lipoprotein cholesterol (p=0.002), intermediate-density lipoprotein cholesterol (p=0.02), and AtherOx levels (p=0.02) but not in patients on lipid-lowering therapy. Patients not on lipid-lowering therapy taking FOS had lower very low-density lipoprotein cholesterol, intermediate-density lipoprotein cholesterol, remnant lipoproteins, triglycerides, low-density lipoprotein cholesterol, AtherOx levels, collagen-induced platelet aggregation, thrombin-induced platelet-fibrin clot strength, and shear elasticity (p<0.03 for all). In clopidogrel-treated patients, there was no difference in ADP-induced aggregation between FOS groups. Patients on FOS had lower urinary 11-dehydrothromboxane B2 levels regardless of lipid-lowering therapy (p<0.04). In conclusion, the findings of this study support the potential benefit of FOS for atherothrombotic risk reduction in sCAD with the greatest benefit in patients not receiving lipid-lowering therapy. Future prospective studies to compare FOS with lipid-lowering therapy and to assess the independent effects of FOS on thrombogenicity are needed.

Dietary n-3 polyunsaturated fatty acid intakes modify the effect of genetic variation in fatty acid desaturase 1 on coronary artery disease

BACKGROUND

Previous studies suggested that dietary fatty acids could affect blood lipids by interacting with genetic variations in fatty acid desaturase 1 (FADS1). However, little is known about their direct effects on coronary artery disease (CAD). The aim of this study was to evaluate whether dietary n-3 long-chain polyunsaturated fatty acids (LCPUFAs)-eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) could modulate the effect of FADS1 rs174547 polymorphism on CAD.

METHODS

FADS1 single-nucleotide polymorphisms rs174547 genotypes were measured in 440 CAD patients and 838 healthy controls. Dietary EPA and DHA intakes were assessed with a validated quantitative frequency food questionnaire. The association between FADS1 rs174547 and CAD was estimated using logistic regression under both dominant and additive genetic models. The interactions between rs174547 polymorphism and LCPUFAs were analyzed by using multiple logistic regression and the "genotype × n-3 LCPUFAs" interaction term was included into the model.

RESULTS

We found that the minor T allele of FADS1 rs174547 increased CAD risk (OR = 1.36, 95%CIs 1.03-1.80), and observed significant interaction between rs174547 and dietary EPA intakes on CAD (P-interaction = 0.028). The T-allele was only associated with higher CAD risk among individuals with lower dietary EPA intakes, but not in those with higher EPA intakes. Similarly, significant interaction was also observed between rs174547 and dietary DHA intakes on CAD (P-interaction = 0.020).

CONCLUSIONS

Dietary n-3 LCPUFA intakes could modulate the association between FADS1 rs174547 polymorphism and CAD. High dietary n-3 LCPUFA intakes could negate the unfavorable effect of genetic variation in FADS1 on CAD in middle-aged and elderly Chinese population.

Impact of fatty acids on brain circulation, structure and function

The use of dietary intervention has evolved into a promising approach to prevent the onset and progression of brain diseases. The positive relationship between intake of omega-3 long chain polyunsaturated fatty acids (ω3-LCPUFAs) and decreased onset of disease- and aging-related deterioration of brain health is increasingly endorsed across epidemiological and diet-interventional studies. Promising results are found regarding to the protection of proper brain circulation, structure and functionality in healthy and diseased humans and animal models. These include enhanced cerebral blood flow (CBF), white and gray matter integrity, and improved cognitive functioning, and are possibly mediated through increased neurovascular coupling, neuroprotection and neuronal plasticity, respectively. Contrary, studies investigating diets high in saturated fats provide opposite results, which may eventually lead to irreversible damage. Studies like these are of great importance given the high incidence of obesity caused by the increased and decreased consumption of respectively saturated fats and ω3-LCPUFAs in the Western civilization. This paper will review in vivo research conducted on the effects of ω3-LCPUFAs and saturated fatty acids on integrity (circulation, structure and function) of the young, aging and diseased brain.

A new, microalgal DHA- and EPA-containing oil lowers triacylglycerols in adults with mild-to-moderate hypertriglyceridemia

In this double-blind, parallel trial, 93 healthy adults with hypertriglyceridemia (triacylglycerols [TAG] 150-499 mg/dL) were randomized to receive either a nutritional oil derived from marine algae (DHA-O; 2.4 g/day docosahexaenoic acid [DHA] and eicosapentaenoic acid [EPA] in a 2.7:1 ratio), fish oil (FO; 2.0 g/day DHA and EPA in a 0.7:1 ratio), or a corn oil/soy oil control as 4-1g softgel capsules/day with meals for 14 weeks; and were instructed to maintain their habitual diet. Percent changes from baseline for DHA-O, FO, and control, respectively, were TAG (-18.9, -22.9, 3.5; p<0.001 DHA-O and FO vs. control), low-density lipoprotein cholesterol (4.6, 6.8, -0.6; p<0.05 DHA-O and FO vs. control), and high-density lipoprotein cholesterol (4.3, 6.9, 0.6; p<0.05 FO vs. control). This study demonstrated that ingestion of microalgal DHA-O providing 2.4 g/day DHA+EPA lowered TAG levels to a degree that was not different from that of a standard fish oil product, and that was significantly more than for a corn oil/soy oil control.

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.

Opportunities to enhance alternative sources of long-chainn-3 fatty acids within the diet

Health benefits or advocated health benefits of long-chain (LC)n-3 PUFA are better known by medical doctors as well as by consumers, so that consumption increases. In addition, the development of aquaculture requires more fishmeal and fish oil. Humanisation of care of companion animals is also associated with addition of LCn-3 PUFA in pet foods. The risk of the increased demand for LCn-3 PUFA is the excess harvesting of natural sources, especially of marine origin (oily fishes, krill). In order to improve sustainability, alternative sources of LCn-3 PUFA have been developed. These alternative sources are: (a) terrestrial plants naturally or genetically enriched in stearidonic acid (SDA), which bypasses the first limiting step of (i.e. ∆6 desaturase) of the biosynthesis of LCn-3 PUFA; (b) single-cell oils rich in LCn-3 PUFA (microalgae,Escherichia coli) and krill. Currently, plants rich in SDA are expensive, metabolic engineering is unfavourably accepted by consumers in many countries, cultivation of microalgae is very expensive even though their ability (for some of them) to synthesise biofuels could induce a decrease in industrial costs, and Antarctic krill harvest must be restricted. Thus, it is difficult to predict their real development in the future.

Modifying influence of dietary sugar in the relationship between cortisol and visceral adipose tissue in minority youth

OBJECTIVE

Cortisol has been associated with preferential visceral adipose tissue (VAT) deposition; however, findings in humans are mixed, which may be clarified when diet is considered.

DESIGN AND METHODS

Participants included 165 African-American and Latino, overweight adolescents (BMI% 97.2±3.2%, ages 13-18, 67% Latino, 66% female). Body composition was determined by dual energy X-ray absorptiometry, abdominal fat depots [VAT, subcutaneous (SAT)] by multiple-slice MRI, time-controlled serum sample to measure cortisol, and 2-day multi-pass 24-hour dietary recall. Linear regression analysis examined the cross-sectional relationship between cortisol, and the interaction of diet and cortisol on adiposity measures. Sex, race, age, and total body fat were a priori covariates.

RESULTS

There was a significant interaction between cortisol and sugar (total and added) in the prediction of VAT (P(interaction)  ≤ 0.05). Amongst participants with high total or added-sugar intake, cortisol was significantly associated with VAT (ß = 0.031 P < 0.001; ß = 0.026 P < 0.001), with no relationship in low consumers of total or added-sugar.

CONCLUSION

Dietary sugar may play an important role in modifying the relationship between cortisol and VAT, such that cortisol is significantly associated with elevated VAT under conditions of high sugar intake.

Comparative effectiveness of fish oil versus fenofibrate, gemfibrozil, and atorvastatin on lowering triglyceride levels among HIV-infected patients in routine clinical care

OBJECTIVE

The goal of this study was to compare the effectiveness of fish oil, fenofibrate, gemfibrozil, and atorvastatin on reducing triglyceride (TG) levels among a large cohort of HIV-infected patients in clinical care.

DESIGN

Retrospective observational cohort study.

METHODS

The primary endpoint was absolute change in TG levels measured using the last TG value pretreatment and the first TG value posttreatment. A pre-post quasi-experimental design was used to estimate the change in TG because of initiating fish oil. Linear regression models examined the comparative effectiveness of treatment with fish oil versus gemfibrozil, fenofibrate, or atorvastatin for TG reduction. Models were adjusted for baseline differences in age, sex, race, CD4⁺ cell count, diabetes, body mass index, protease inhibitor use, and time between TG measures.

RESULTS

A total of 493 patients (mean age, 46 years; 95% male) were included (46 patients receiving gemfibrozil; 80, fenofibrate; 291, atorvastatin; and 76, fish oil) with a mean baseline TG of 347 mg/dL. New use of fish oil decreased TG [ΔTG, -45 mg/dL; 95% confidence interval (CI): -80 to -11] in the pre-post study. Compared with fish oil (reference), fibrates were more effective (ΔTG, -66; 95% CI: -120 to -12) in reducing TG levels, whereas atorvastatin was not (ΔTG, -39; 95% CI: -86 to 9).

CONCLUSIONS

In HIV-infected patients in routine clinical care, fish oil is less effective than fibrates (but not atorvastatin) at lowering TG values. Fish oil may still represent an attractive alternative for patients with moderately elevated TGs, particularly among patients who may not want or tolerate fibrates.