Omega-3 fatty acid supplementation enhances stroke volume and cardiac output during dynamic exercise

Effect of Omega-3 Polyunsaturated Fatty Acids Intake on Eosinophil Airway Inflammation in University Athletes

Background

Though athletes have a high risk of respiratory disorders, effective prevention has not yet to be identified. Omega-3 (n-3) polyunsaturated fatty acids (PUFA) have some practical anti-inflammatory effects in allergy, and therefore may reduce airway inflammation in athletes. This study aimed to assess whether n-3 PUFA intake affects airway inflammation in university athletes.

Methods

Twenty-three males were divided into three groups: 1) the eosinophilic airway inflammation group (I_PUFA group; fractional exhaled nitric oxide (FeNO ≥ 25 ppb, n = 10); 2) the non-eosinophilic airway inflammation group (N_PUFA group; FeNO < 25 ppb, exhaled carbon dioxide (eCO) ≥ 3.6 ppm, n = 5); and 3) the control group (FeNO < 25 ppb, eCO < 3.6 ppm, n = 8). Participants took supplements containing 260 mg of docosapentaenoic acid and 600 mg of eicosapentaenoic acid (EPA) daily for 3 weeks. Baseline measurements of FeNO, respiratory impedance, respiratory function, dietary intake (food frequency questionnaires), and blood tests were performed. FeNO and respiratory impedance were measured weekly, and the rest were measured after 3 weeks.

Results

There was a significant decrease in FeNO levels from baseline at 2 and 3 weeks in the I_PUFA group (54.7 ± 8.5 ppb vs. 45.1 ± 9.1 and 45.4 ± 7.7 ppb; mean ± standard error (SE), P < 0.05). After 3 weeks, FeNO levels remained unchanged in the N_PUFA and control groups, and respiratory impedance and function remained unchanged in all groups. Blood EPA levels significantly increased in the I_PUFA and N_PUFA groups (I_PUFA, 27.7 ± 16.9 vs. 52.1 ± 12.3 µg/mL; N_PUFA, 20.8 ± 8.7 vs. 70.4 ± 36.1 µg/mL; mean ± standard deviation (SD), P < 0.05). No changes were observed in dietary intake over the 3 weeks.

Conclusions

n-3 PUFA supplementation for 3 weeks reduced airway inflammation in athletes with FeNO levels ≥ 25 ppb.

Exercise Training Combined with Calanus Oil Supplementation Improves the Central Cardiodynamic Function in Older Women

The aim of this study was to investigate the possible beneficial effects of exercise training (ET) with omega-3/Calanus oil supplementation on cardiorespiratory and adiposity parameters in elderly women. Fifty-five women (BMI: 19–37 kg/m², 62–80 years old) were recruited and randomly assigned to the 4 month intervention with ET and omega-3 supplementation (Calanus oil, ET-Calanus) or ET and the placebo (sunflower oil; ET-Placebo). The body composition was determined by dual-energy X-ray absorptiometry (DXA), and cardiorespiratory parameters were measured using spiroergometry and PhysioFlow hemodynamic testing. Both interventions resulted in an increased lean mass whereas the fat mass was reduced in the leg and trunk as well as the android and gynoid regions. The content of trunk fat (in percent of the total fat) was lower and the content of the leg fat was higher in the ET-Calanus group compared with the ET-Placebo. Although both interventions resulted in similar improvements in cardiorespiratory fitness (VO_2max), it was explained by an increased peripheral oxygen extraction (a-vO₂diff) alone in the ET-Placebo group whereas increased values of both a-vO₂diff and maximal cardiac output (CO_max) were observed in the ET-Calanus group. Changes in CO_max were associated with changes in systemic vascular resistance, circulating free fatty acids, and the omega-3 index. In conclusion, Calanus oil supplementation during a 4 month ET intervention in elderly women improved the cardiorespiratory function, which was due to combined central and peripheral cardiodynamic mechanisms.

The influence of a basic military training diet on whole blood fatty acid profile and the Omega-3 Index of Australian Army recruits

This study described the whole blood fatty acid profile and Omega-3 Index (O3I) of Australian Army recruits at the commencement and completion of basic military training (BMT). Eighty (80) males (17-34 y, 77.4±13.0 kg, 43.5±4.3 mL/kg/min) and 37 females (17-45 y, 64.3±8.8 kg, 39.3±2.7 mL/kg/min) volunteered to participate (N=117). Whole blood samples of each recruit were collected using a finger prick in weeks 1 and 11 (n=82) and analysed via gas chromatography for the relative proportions of each fatty acid (mean [95% CI]). The macronutrient characteristics of the diet offerings was also determined. At commencement there was a low omega-3 status (sum of omega-3; 4.95% [4.82-5.07]) and O3I (5.03% [4.90-5.16]) and no recruit recorded an O3I >8% (desirable). The omega-6/omega-3 (7.04 [6.85-7.23]) and arachidonic acid / eicosapentaenoic acid (AA/EPA) (18.70 [17.86-19.53]) ratios for the cohort were also undesirable. The BMT mess menu provided a maximum of 190 mg/day of eicosapentaenoic acid (EPA) and 260 mg/day of docosahexaenoic acid (DHA). The O3I of the recruits was lower by week 11 (4.62% [4.51-4.78], p<0.05), the omega-6/omega-3 increased (7.27 [7.07-7.47] p<0.05) and the AA/EPA remained elevated (17.85 [16.89-18.81]). In conclusion, Australian Army recruits' omega-3 status remained undesirable during BMT and deserves nutritional attention. Novelty Bullets • Australian Army recruits' Omega-3 Index, at the commencement of BMT, was reflective of the Western-style diet. • The BMT diet offered minimum opportunity for daily EPA and DHA consumption. • Every recruit experienced a further reduction of their Omega-3 Index during BMT.

Muscular endurance and muscle metabolic responses to 8 weeks of omega-3 polyunsaturated fatty acids supplementation

BACKGROUND

It has been well known that exercise training improves muscular endurance; however, whether nutritional strategies can be used to enhance muscular endurance remains unclear. Herein, we tested the hypothesis that 8 weeks of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplementation, known to promote oxygen availability and lipid metabolism, would attenuate muscular fatigue caused by numerous muscle contractions.

METHODS

Nineteen healthy men were randomly assigned to a placebo group (n = 9) and fish oil group (n = 10) in a double-blind fashion. The fish oil group consumed EPA-rich fish oil that contains 600-mg EPA and 260-mg DHA per day for 8 weeks. The placebo group received matching capsules for the same duration of time. After the 8-week intervention, subjects performed muscular endurance test that was repeated knee extensions with weights equal to 40% of the subject's body weight.

RESULTS

Maximal repetitions to exhaustion were recorded. In addition, maximum isometric voluntary muscle contraction (MVC), muscle metabolism using near-infrared spectroscopy, and blood lactate were measured during the test. Subjects in both groups reached exhaustion after the muscular endurance test, while the maximal repetitions did not differ between the groups. Similarly, there is no significant difference in oxygen saturation in muscle tissue (StO2), an index of muscle oxygen availability, between the groups. Also, MVC and blood lactate did not change between groups.

CONCLUSION

In conclusion, the present study provided evidence that muscle fatigue caused by knee extensions cannot be attenuated by EPA and DHA supplementation in healthy subjects.

Are There Benefits from the Use of Fish Oil Supplements in Athletes? A Systematic Review

Despite almost 25 y of fish oil supplementation (FS) research in athletes and widespread use by the athletic community, no systematic reviews of FS in athletes have been conducted. The objectives of this systematic review are to: 1) provide a summary of the effect of FS on the athlete's physiology, health, and performance; 2) report on the quality of the evidence; 3) document any side effects as reported in the athlete research; 4) discuss any risks associated with FS use; and 5) provide guidance for FS use and highlight gaps for future research. Electronic databases (PubMed, Embase, Web of Science, Google Scholar) were searched up until April 2019. Only randomized placebo-controlled trials (RCTs) in athletes, assessing the effect of FS on a health, physiological/biochemical, or performance variable were included. Of the 137 papers identified through searches, 32 met inclusion criteria for final analysis. Athletes varied in classification from recreational to elite, and from Olympic to professional sports. Mean age for participants was 24.9 ± 4.5 y, with 70% of RCTs in males. We report consistent effects for FS on reaction time, mood, cardiovascular dynamics in cyclists, skeletal muscle recovery, the proinflammatory cytokine TNF-α, and postexercise NO responses. No clear effects on endurance performance, lung function, muscle force, or training adaptation were evident. Methodological quality, applying the Physiotherapy Evidence Database (PEDro) scale, ranged from 6 to a maximum of 11, with only 4 RCTs reporting effect sizes. Few negative outcomes were reported. We report various effects for FS on the athlete's physiology; the most consistent findings were on the central nervous system, cardiovascular system, proinflammatory cytokines, and skeletal muscle. We provide recommendations for future research and discuss the potential risks with FS use.

Correlation between invasive and noninvasive blood pressure measurements in severely burned children

INTRODUCTION

Accurate blood pressure monitoring is essential for burn management, with the intra-arterial line method being the gold standard. Here we evaluated agreement between cuff and intra-arterial line methods.

METHODS

Data from burned children admitted from 1997 to 2016 were retrospectively reviewed. Simultaneously collected intra-arterial and cuff measurements were cross-matched and linear regression performed to assess agreement for systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP).

RESULTS

We identified 9969 matches for SBP, DBP, and MAP in 872 patients (579 male) aged 8±5years with burns covering 52±20% of the total body surface area and a hospitalization lasting 33±31 days. Intra-arterial lines had a complication rate of 1%. The mean bias (95% CI) between methods was 1.3 (0.5, 2.1) mm Hg for SBP, -6.4 (-7.0, -5.7) mmHg for DBP, and -5.8 (-6.4, -5.3) mmHg for MAP. The standard deviation of the bias (95% limit of agreement) was 12.1 (-22.5, 25.1) mmHg for SBP, 9.9 (-25.8, 13.0) mmHg for DBP, and 8.7 (-22.8, 11.1) mmHg for MAP.

CONCLUSIONS

Cuff measurements vary widely from those of intra-arterial lines, which have a low complication rate. Intra-arterial lines are advisable when tight control of the hemodynamic response is essential.

Effect of omega-3 long-chain polyunsaturated fatty acid supplementation on heart rate: a meta-analysis of randomized controlled trials

Background

Elevated resting heart rate (HR) has emerged as a new risk factor for all-cause and cardiovascular mortality. The effect of marine-derived omega-3 long-chain polyunsaturated fatty acid (n−3 LCPUFAs) supplementation on HR was investigated as an outcome in many clinical trials. The present study was to provide an updated meta-analysis on the HR-slowing effect of n−3 LCPUFAs, and to differentiate the chronotropic effect between eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

Methods

PubMed and Cochrane databases were searched for relevant articles examining the effects of n−3 PUFAs on HR through May 2017. A random-effects model was used to generate the pooled effect sizes and 95% confidence intervals (CIs). The pooled effect sizes were presented as weighted mean differences (WMDs).

Results

A total of 51 randomized controlled trials (RCTs) with approximately 3000 participants were included in this meta-analysis. Compared to placebo, n−3 PUFA supplementation mildly but significantly reduced HR (−2.23 bpm; 95% CI: −3.07, −1.40 bpm). Moderate evidence of heterogeneity was observed among included trials (I² = 49.1%, P heterogeneity < 0.001). When DHA and EPA were separately administered, modest HR reduction was observed in trials that supplemented with DHA (−2.47 bpm; 95% CI: −3.47, −1.46 bpm), but not in trials with EPA.

Conclusions

The present meta-analysis provides strong clinical evidence demonstrating the effect of heart rate reduction by n−3 LCPUFA supplementation. When DHA or EPA administered alone, heart rate was slowed by DHA rather than by EPA.

Comparable reductions in hyperpnoea-induced bronchoconstriction and markers of airway inflammation after supplementation with 6·2 and 3·1 g/d of long-chain n-3 PUFA in adults with asthma

Although high dose n-3 PUFA supplementation reduces exercise- and hyperpnoea-induced bronchoconstriction (EIB/HIB), there are concurrent issues with cost, compliance and gastrointestinal discomfort. It is thus pertinent to establish the efficacy of lower n-3 PUFA doses. Eight male adults with asthma and HIB and eight controls without asthma were randomly supplemented with two n-3 PUFA doses (6·2 g/d (3·7 g EPA and 2·5 g DHA) and 3·1 g/d (1·8 g EPA and 1·3 g DHA)) and a placebo, each for 21 d followed by 14 d washout. A eucapnic voluntary hyperpnoea (EVH) challenge was performed before and after treatments. Outcome measures remained unchanged in the control group. In the HIB group, the peak fall in forced expiratory volume in 1 s (FEV1) after EVH at day 0 (-1005 (sd 520) ml, -30 (sd 18) %) was unchanged after placebo. The peak fall in FEV1 was similarly reduced from day 0 to day 21 of 6·2 g/d n-3 PUFA (-1000 (sd 460) ml, -29 (sd 17) % v. -690 (sd 460) ml, -20 (sd 15) %) and 3·1 g/d n-3 PUFA (-970 (sd 480) ml, -28 (sd 18) % v. -700 (sd 420) ml, -21 (sd 15) %) (P<0·001). Baseline fraction of exhaled nitric oxide was reduced by 24 % (P=0·020) and 31 % (P=0·018) after 6·2 and 3·1 g/d n-3 PUFA, respectively. Peak increases in 9α, 11β PGF2 after EVH were reduced by 65 % (P=0·009) and 56 % (P=0·041) after 6·2 and 3·1 g/d n-3 PUFA, respectively. In conclusion, 3·1 g/d n-3 PUFA supplementation attenuated HIB and markers of airway inflammation to a similar extent as a higher dose. Lower doses of n-3 PUFA thus represent a potentially beneficial adjunct treatment for adults with asthma and EIB.

The relation of red blood cell fatty acids with vascular stiffness, cardiac structure and left ventricular function: the Framingham Heart Study

Polyunsaturated fatty acids have been associated with beneficial influences on cardiovascular health. However, the underlying mechanisms are not clear, and data on the relations of polyunsaturated fatty acids to subclinical disease measures such as vascular stiffness and cardiac function are sparse and inconclusive. In a large community-based cohort, we examined the relations of omega-3 and other fatty acids to a comprehensive panel of vascular function measures (assessing microvascular function and large artery stiffness), cardiac structure and left ventricular function. Red blood cell (RBC) membrane fatty acid composition, a measure of long-term fatty acid intake, was assessed in participants of the Framingham Offspring Study and Omni cohorts and related to tonometry-derived measures of vascular stiffness and to a panel of echocardiographic traits using partial correlations. Up to n=3055 individuals (56% women, mean age 66 years) were available for analyses. In age- and sex-adjusted models, higher RBC omega-3 content was moderately associated (p≤0.002) with several measures of vascular stiffness and function in a protective direction. However, after multivariable adjustment, only an association of higher RBC omega-3 content with lower carotid-femoral pulse wave velocity (a measure of aortic stiffness) remained significant (r = -0.06, p=0.002). In secondary analyses, higher linoleic acid, the major nutritional omega-6 fatty acid, was associated with smaller left atrial size, even after multivariable adjustment (r = -0.064, p<0.001). In conclusion, in our cross-sectional community-based study, we found several associations consistent with the notion of protective effects of omega-3 and linoleic acid. The clinical significance of these modest associations remains to be elucidated.

Long-chain omega-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid and blood pressure: a meta-analysis of randomized controlled trials

BACKGROUND

Although a large body of literature has been devoted to examining the relationship between eicosapentaenoic and docosahexaenoic acids (EPA+DHA) and blood pressure, past systematic reviews have been hampered by narrow inclusion criteria and a limited scope of analytical subgroups. In addition, no meta-analysis to date has captured the substantial volume of randomized controlled trials (RCTs) published in the past 2 years. The objective of this meta-analysis was to examine the effect of EPA+DHA, without upper dose limits and including food sources, on blood pressure in RCTs.

METHODS

Random-effects meta-analyses were used to generate weighted group mean differences and 95% confidence intervals (CIs) between the EPA+DHA group and the placebo group. Analyses were conducted for subgroups defined by key subject or study characteristics.

RESULTS

Seventy RCTs were included. Compared with placebo, EPA+DHA provision reduced systolic blood pressure (−1.52mm Hg; 95% confidence interval (CI) = −2.25 to −0.79) and diastolic blood pressure (−0.99mm Hg; 95% CI = −1.54 to −0.44) in the meta-analyses of all studies combined. The strongest effects of EPA+DHA were observed among untreated hypertensive subjects (systolic blood pressure = −4.51mm Hg, 95% CI = −6.12 to −2.83; diastolic blood pressure = −3.05mm Hg, 95% CI = −4.35 to −1.74), although blood pressure also was lowered among normotensive subjects (systolic blood pressure = −1.25mm Hg, 95% CI = −2.05 to −0.46; diastolic blood pressure = −0.62mm Hg, 95% CI = −1.22 to −0.02).

CONCLUSIONS

Overall, available evidence from RCTs indicates that provision of EPA+DHA reduces systolic blood pressure, while provision of ≥2 grams reduces diastolic blood pressure.

Marine bioactives and potential application in sports

An enriched diet with antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic compounds, has always been suggested to improve oxidative stress, preventing related diseases. In this respect, marine natural product (MNP), such as COX inhibitors, marine steroids, molecules interfering with factors involved in the modulation of gene expression (such as NF-κB), macrolides, many antioxidant agents, thermogenic substances and even substances that could help the immune system and that result in the protection of cartilage, have been recently gaining attention. The marine world represents a reserve of bioactive ingredients, with considerable potential as functional food. Substances, such as chitin, chitosan, n-3 oils, carotenoids, vitamins, minerals and bioactive peptides, can provide several health benefits, such as the reduction of cardiovascular diseases, anti-inflammatory and anticarcinogenic activities. In addition, new marine bioactive substances with potential anti-inflammatory, antioxidant and thermogenic capacity may provide health benefits and performance improvement, especially in those who practice physical activity, because of their increased free radical and Reacting Oxygen Species (ROS) production during exercise, and, particularly, in athletes. The aim of this review is to examine the potential pharmacological properties and application of many marine bioactive substances in sports.

The essentials of essential fatty acids

All fats, including saturated fatty acids, have important roles in the body. However, the most important fats are those that the body cannot make and thus must come from the food we eat. These essential fatty acids (EFAs) are based on linoleic acid (omega-6 group) and alpha-linolenic acid (omega-3 group). We need both groups of essential fatty acids to survive. For various reasons EFA deficiency is common in the general population, as is a disproportionate intake of omega-6 fatty acids over omega-3 fatty acids. As such, it is important to eat the right foods to make sure that you're taking in enough and the right kinds of the essential fatty acids. However, there is much more to the story. Studies have shown that increasing the intake of certain essential fatty acids, either alone or in combination with other fats and compounds, can increase health, help in treating certain diseases, and even improve body composition, mental and physical performance.

Effects of marine-derived omega-3 fatty acids on systemic hemodynamics at rest and during stress: a dose-response study

BACKGROUND

Omega-3 fatty acids reduced heart rate (HR) and blood pressure (BP) in some studies, but dose-response studies are rare, and little is known about underlying mechanisms.

PURPOSE

We examined effects of 0.85 g/day eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) (low dose) and 3.4 g/day EPA + DHA (high dose) on HR and systemic hemodynamics during rest, speech, and foot cold pressor tasks.

METHODS

This was a dose-response, placebo-controlled, double-blind, randomized, crossover trial (8-week treatment, 6-week washout) in 26 adults.

RESULTS

Throughout the testing sessions, HR was reduced in a dose-dependent manner. The high dose reduced BP and stroke volume and increased pre-ejection period. Reductions in BP were associated with increases in erythrocyte omega-3 fatty acids.

CONCLUSIONS

High-dose long-chain omega-3 fatty acids can reduce BP and HR, at rest and during stress. These findings suggest that at-risk populations may achieve benefits with increased omega-3 intake. The trial was registered on ClinicalTrials.gov (NCT00504309).

A comparison of the changes in cardiac output and systemic vascular resistance during exercise following high-fat meals containing DHA or EPA

Long-chain n-3 PUFA can lower blood pressure (BP) but their acute effects on cardiac output, BP and systemic vascular resistance (SVR) in response to dynamic exercise are uncertain. We compared the effects of high-fat meals rich in EPA (20 : 5n-3), DHA (22 : 6n-3) or oleic acid (control) on cardiac output, BP and SVR in response to exercise stress testing. High-fat meals (50 g fat) containing high-oleic sunflower oil enriched with 4·7 g of either EPA or DHA v. control (high-oleic sunflower oil only) were fed to twenty-two healthy males using a randomised cross-over design. Resting measurements of cardiac output, heart rate and BP were made before and hourly over 5 h following the meal. A standardised 12 min exercise test was then conducted with further measurements made during and post-exercise. Blood samples were collected at fasting, 5 h postprandially and immediately post-exercise for the analysis of lipid, glucose and 8-isoprostane-F2α (8-iso-PGF2α). Plasma concentrations of EPA and DHA increased by 0·22 mmol/l 5 h following the EPA and DHA meals, respectively, compared with the control (P < 0·001). Resting cardiac output and 8-iso-PGF2α increased similarly following all meals and there were no significant differences in cardiac output during exercise between the meals. SVR was lower at 5 h and during exercise following the DHA but not EPA meal, compared with the control meal, by 4·9 % (95 % CI 1·3, 8·4; P < 0·01). Meals containing DHA appear to differ from EPA with regard to their effects on cardiovascular haemodynamics during exercise.

The virtual liver: a multidisciplinary, multilevel challenge for systems biology

The liver is the central metabolic organ in human physiology, with functions that are fundamentally important to the detoxification of xenobiotics (drugs), the maintenance of homeostasis of numerous blood metabolites, and the production of mediators of the acute phase response. Liver toxicity, whether actual or implied is the reason for the failure of a significant proportion of many promising novel medicines that consequently never reach the market, and diseases such as atherosclerosis, diabetes, and fatty liver diseases, that are a major burden on current health resources, are directly linked to functional and structural disorders of the liver. This article presents the concepts and approaches underpinning one of the most exciting and ambitious modeling projects in the field of systems biology and systems medicine. This major multidisciplinary research program is aimed at developing a whole-organ model of the human liver, representing its central physiological functions under normal and pathological conditions The model will be composed of a larger battery of interconnected submodels representing liver anatomy and physiology, integrating processes across hierarchical levels in space, time, and structural organization. In this article, we outline the general architecture of the liver model and present first step taken to reach this ambitious goal.

Pharmacology of dimethyl sulfoxide in cardiac and CNS damage

The pharmacological effects of dimethyl sulfoxide (DMSO) administration include some desirable properties that may be useful in the treatment of medical disorders resulting in tissue injury and compromised organ systems. These properties include the reported effects of DMSO on impaired blood flow, suppression of cytotoxicity from excess glutamate release that may result in lethal NMDA-AMPA activation, restriction of cytotoxic Na(+) and Ca(2+) entry into damaged cells, blocking tissue factor (TF) from contributing to thrombosis, reduction of intracranial pressure, tissue edema, and inflammatory reactions, and inhibition of vascular smooth muscle cell migration and proliferation that can lead to atherosclerosis of the coronary, peripheral, and cerebral circulation. A review of the basic and clinical literature on the biological actions of DMSO in cardiac and central nervous system (CNS) damage or dysfunction indicates that this agent, alone or in combination with other synergistic molecules, has been reported to neutralize or attenuate pathological complications that harmed or can further harm these two organ systems. The effects of DMSO make it potentially useful in the treatment of medical disorders involving head and spinal cord injury, stroke, memory dysfunction, and ischemic heart disease.

Resolvins and protectins: mediating solutions to inflammation

Resolution of inflammation has historically been viewed as a passive process, occurring as a result of the withdrawal of pro-inflammatory signals, including lipid mediators such as leukotrienes and prostaglandins. Thus, most anti-inflammatory drugs have traditionally targeted primarily mediator pathways that are engaged at the onset of inflammation. Only recently has it been established that inflammation resolution is an active process with a distinct set of chemical mediators. Several clinical and epidemiological studies have identified beneficial effects of polyunsaturated fatty acids (PUFAs) for a variety of inflammatory diseases, yet without mechanistic explanations for these beneficial effects. Resolvins and protectins are recently identified molecules that are generated from omega-3 PUFA precursors and can orchestrate the timely resolution of inflammation in model systems. Dysregulation of pro-resolving mediators is associated with diseases of prolonged inflammation, so designing pharmacological mimetics of naturally occurring pro-resolving mediators offers exciting new targets for drug design. This review describes the discovery and synthesis of these novel lipid mediators, their receptors and mechanisms of action, and summarizes the studies to date that have uncovered roles for resolvins and protectins in disease states.

Recent insights on chronic heart failure, cachexia and nutrition

PURPOSE OF REVIEW

To provide recent observations on the interrelation between chronic heart failure (CHF), cachexia and human nutrition and updating epidemiological issues in CHF.

RECENT FINDINGS

Present evidence suggests that impairment in cardiac muscle energetics plays an important role in the pathogenesis of heart failure. New concepts such as microRNA expression are emerging as potential agents in heart failure. Recent research suggests mechanisms by which inflammatory catabolic states may persist in the presence of adequate growth factors and nutrition. A consensus panel has recently designed a definition for general cachexia and its stratification. Together with classicals, new nutrients and substrates are showing efficacies in the malnutrition associated with CHF. Although still promising, ghrelin, growth factors and other biological compounds maintain emergent therapeutical positions for heart failure or associated catabolic states or both.

SUMMARY

Altered intestinal function as an agent for CHF is rising in evidence. New techniques to well diagnose and stratify malnutrition and cardiac cachexia in CHF are needed. Treatment of cachexia in CHF appears to be a combination of different approaches, in which metabolic, nutritional, immunological and hormonal strategies may play an important role. Although the current experimental research is of great help, well designed randomized controlled trials are needed to test these hypothesis and generate clinical evidence.

Towards establishing dietary reference intakes for eicosapentaenoic and docosahexaenoic acids

There is considerable interest in the impact of (n-3) long-chain PUFA in mitigating the morbidity and mortality caused by chronic diseases. In 2002, the Institute of Medicine concluded that insufficient data were available to define Dietary Reference Intakes (DRI) for eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA), noting only that EPA and DHA could contribute up to 10% toward meeting the Adequate Intake for alpha-linolenic acid. Since then, substantial new evidence has emerged supporting the need to reassess this recommendation. Therefore, the Technical Committee on Dietary Lipids of the International Life Sciences Institute North America sponsored a workshop on 4-5 June 2008 to consider whether the body of evidence specific to the major chronic diseases in the United States--coronary heart disease (CHD), cancer, and cognitive decline--had evolved sufficiently to justify reconsideration of DRI for EPA+DHA. The workshop participants arrived at these conclusions: 1) consistent evidence from multiple research paradigms demonstrates a clear, inverse relation between EPA+DHA intake and risk of fatal (and possibly nonfatal) CHD, providing evidence that supports a nutritionally achievable DRI for EPA+DHA between 250 and 500 mg/d; 2) because of the demonstrated low conversion from dietary ALA, protective tissue levels of EPA+DHA can be achieved only through direct consumption of these fatty acids; 3) evidence of beneficial effects of EPA+DHA on cognitive decline are emerging but are not yet sufficient to support an intake level different from that needed to achieve CHD risk reduction; 4) EPA+DHA do not appear to reduce risk for cancer; and 5) there is no evidence that intakes of EPA+DHA in these recommended ranges are harmful.