Effect of dietary monounsaturated and polyunsaturated fatty acids on the susceptibility of plasma low density lipoproteins to oxidative modification

Smoking Induces the Circulating Levels of Matrix Metalloproteinase-9 and Its Association with Cardiovascular Risk in Young Smokers

Objective

Smoking causes cardiovascular risk, which may alter the stability between the production and degradation of the extracellular matrix. Matrix metalloproteinase-9 (MMP-9) is a zinc-containing endopeptidase that degrades the extracellular matrix and is involved in tissue remodelling and several physiological processes. As a result, smoking-induced elevated serum MMP-9 levels, particularly at a younger age, raise the risk of coronary heart disease (CHD). Thus, this study aimed to determine the possible relationship between smoking-induced circulating MMP-9 and the risk of cardiovascular disease in young smokers.

Methods

In this cross-sectional study, the patients were divided into three groups. Each group contains 120 study participants. Group one consisted of 120 healthy individuals with no physical and mental illness, group two consisted of 120 active smokers with a heart disease, and group three consisted of 120 active smokers with a heart disease and diabetes, who attended Sri Ramaswamy Memorial Hospital for cardiology checkup at the age of 20-55 years. The serum MMP-9, high-sensitivity C-reactive protein (hs-CRP), and apolipoprotein-E (APO-E) levels were analyzed using the ELISA method, and the lipid levels were measured enzymatically using AU480 automatic analyzer (Beckman Coulter).

Results

Compared with non-smokers, the study shows that the mean serum MMP-9, hs-CRP, and APO-E levels were significantly higher in smokers (p<0.001). A strong relationship was also found between MMP-9 and hs-CRP, APO-E, smoking load, and smoking intensity.

Conclusions

A significant association was found between cigarette smoking with MMP-9, and relative exposure to circulating inflammation markers plays a potential role in the pathogenesis of CHD.

Surgical castration versus chemical castration in donkeys: response of stress, lipid profile and redox potential biomarkers

Background

Castration is a husbandry practice raising important questions on the welfare and physiological status of farm animals. Searching for effective castration methods that minimally compromise the body physiology is worthy of attention. Therefore, this study aimed to evaluate the differential response of biological systems in donkeys to surgical castration versus the chemical one by CaCl₂ with special emphasis on stress, lipid profile, and oxidative stress biomarkers. Donkeys were divided randomly and equally into two groups; the chemical (Ch) and surgical (S) groups (n = 6). The Ch group was chemically castrated by intratesticular injection of 20% CaCl₂ dissolved in absolute ethanol. Blood samples were collected prior to castration and at 15, 30, 45, and 60 days after the beginning of experiment.

Results

Surprisingly, the Ch group at the end of the experiment was characterized by significantly higher cortisol level compared to the S group. TC and LDL-C levels in the S group significantly decreased at day 45, while TG levels significantly increased at days 45 and 60 in comparison with day 0. HDL-C levels at days 30 and 60 in the Ch group significantly increased in comparison with day 0. At day 30 post-castration, HDL-C was significantly higher and LDL-C was significantly lower in the Ch group than the S group. A significant elevation in TC and LDL-C was observed at day 45 and in HDL-C at the end of experimental duration in the Ch group when compared with the S group. TPX level was significantly lower and TAC was significantly higher in the Ch group at day 45 than the S group.

Conclusion

Surgical castration evoked less stress and minor changes in lipid profile and oxidant/antioxidant balance relative to chemical castration by intratesticular 20% CaCl₂ dissolved in absolute ethanol.

Mediterranean Diet Increases Endothelial Function in Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

The endothelium plays a key role in the maintenance of vascular health and represents a potential physiological target for dietary and other lifestyle interventions designed to reduce the risk of cardiovascular diseases (CVD) including stroke or coronary heart disease.

OBJECTIVE

To conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) investigating the effects of the Mediterranean dietary pattern (MedDiet) on endothelial function.

METHODS

Medline, Embase, and Scopus databases were searched from inception until January 2019 for studies that met the following criteria: 1) RCTs including adult participants, 2) interventions promoting the MedDiet, 3) inclusion of a control group, and 4) measurements of endothelial function. A random-effects meta-analysis was conducted. Metaregression and subgroup analyses were performed to identify whether effects were modified by health status (i.e., healthy participants versus participants with existing comorbidities), type of intervention (i.e., MedDiet alone or with a cointervention), study duration, study design (i.e., parallel or crossover), BMI, and age of participants.

RESULTS

Fourteen articles reporting data for 1930 participants were included in the meta-analysis. Study duration ranged from 4 wk to 2.3 y. We observed a beneficial effect of the MedDiet on endothelial function [standardized mean difference (SMD): 0.35; 95% CI: 0.17, 0.53; P <0.001; I2 = 73.68%]. MedDiet interventions improved flow-mediated dilation (FMD)-the reference method for noninvasive, clinical measurement of endothelial function-by 1.66% (absolute change; 95% CI: 1.15, 2.17; P <0.001; I2 = 0%). Effects of the MedDiet on endothelial function were not modified by health status, type of intervention, study duration, study design, BMI, or age of participants (P >0.05).

CONCLUSIONS

MedDiet interventions improve endothelial function in adults, suggesting that the protective effects of the MedDiet are evident at early stages of the atherosclerotic process with important implications for the early prevention of CVD. This study has the PROSPERO registration number: CRD42018106188.

Effects of overfeeding on the fatty acid profile and stearoyl-CoA desaturase-1 indices in the liver and subcutaneous adipose tissue in cats

To evaluate the effect of overfeeding on fatty acid distribution and metabolism, especially stearoyl-CoA desaturase-1 (SCD-1) indices, 8 cats in the experimental and control groups (4 per group) were evaluated in this study. The experiments involved feeding the experimental group cats twice their daily energy requirement with a commercial diet for 4 weeks. The control group was fed the estimated daily energy requirement with the same diet. Body weight, feline body mass index, body condition score, several zoometry measurements, and plasma metabolites/hepatic injury markers were measured in all the cats before and after the experiment. In addition, the fatty acid profiles in the liver and subcutaneous adipose tissue were measured after the experiment. After 4 weeks of overfeeding, the experimental group demonstrated significant increases in hepatic C18:1, plasma triglyceride, and nonesterified fatty acid (NEFA) concentrations and in alanine aminotransferase activity. Furthermore, hepatic SCD-1 indices were positively correlated with body weight, feline body mass index, body condition score, and plasma NEFA concentration, although subcutaneous adipose tissue did not demonstrate any increase in SCD-1 indices in this study. The increase in hepatic SCD-1 indices might be enhanced by the inflow of plasma NEFA into the liver, and NEFA toxicity might stimulate C18:1 synthesis by SCD-1.

Diet and longevity: The effects of traditional eating habits on human lifespan extension

Since the dawn of time human beings have been trying to improve the quality of the existence and extend their lifespan. Genetic, environmental, behavioral and dietary factors influence the pathways that regulate aging and life expectancy, thus rendering longevity a very complex phenomenon. Although a long-lived elixir has not yet been found, physicians and scientists agree that nutrition has a major impact on the overall mortality and morbidity, hence becoming the subject of a widespread scientific research. This review describes, analyzes and compares the effects of different types of diets in reducing the onset of typical Western countries non-communicable diseases (NCDs) (cardiovascular diseases, tumors, chronic respiratory diseases, diabetes, etc.), thus increasing the average lifespan. It will first depict the most relevant characteristics, nutraceutical properties and effects on the populations of the Mediterranean, Japanese, Vegetarian and New Nordic Diet. Finally, it will describe the impact of different dietary restrictions in modulating the genetic pathways that regulate metabolism and aging. Overall, this work reinforces the evidence that specific eating habits, in addition to healthy and active lifestyles, are crucial to increase people’s health span and to achieve an optimal longevity.

Staphylococcus aureus Utilizes Host-Derived Lipoprotein Particles as Sources of Fatty Acids

Methicillin-resistant Staphylococcus aureus (MRSA) is a threat to global health. Consequently, much effort has focused on the development of new antimicrobials that target novel aspects of S. aureus physiology. Fatty acids are required to maintain cell viability, and bacteria synthesize fatty acids using the type II fatty acid synthesis (FASII) pathway. FASII is significantly different from human fatty acid synthesis, underscoring the therapeutic potential of inhibiting this pathway. However, many Gram-positive pathogens incorporate exogenous fatty acids, bypassing FASII inhibition and leaving the clinical potential of FASII inhibitors uncertain. Importantly, the source(s) of fatty acids available to pathogens within the host environment remains unclear. Fatty acids are transported throughout the body by lipoprotein particles in the form of triglycerides and esterified cholesterol. Thus, lipoproteins, such as low-density lipoprotein (LDL), represent a potentially rich source of exogenous fatty acids for S. aureus during infection. We sought to test the ability of LDLs to serve as a fatty acid source for S. aureus and show that cells cultured in the presence of human LDLs demonstrate increased tolerance to the FASII inhibitor triclosan. Using mass spectrometry, we observed that host-derived fatty acids present in the LDLs are incorporated into the staphylococcal membrane and that tolerance to triclosan is facilitated by the fatty acid kinase A, FakA, and Geh, a triacylglycerol lipase. Finally, we demonstrate that human LDLs support the growth of S. aureus fatty acid auxotrophs. Together, these results suggest that human lipoprotein particles are a viable source of exogenous fatty acids for S. aureus during infection.IMPORTANCE Inhibition of bacterial fatty acid synthesis is a promising approach to combating infections caused by S. aureus and other human pathogens. However, S. aureus incorporates exogenous fatty acids into its phospholipid bilayer. Therefore, the clinical utility of targeting bacterial fatty acid synthesis is debated. Moreover, the fatty acid reservoir(s) exploited by S. aureus is not well understood. Human low-density lipoprotein particles represent a particularly abundant in vivo source of fatty acids and are present in tissues that S. aureus colonizes. Herein, we establish that S. aureus is capable of utilizing the fatty acids present in low-density lipoproteins to bypass both chemical and genetic inhibition of fatty acid synthesis. These findings imply that S. aureus targets LDLs as a source of fatty acids during pathogenesis.

Benefits of Nut Consumption on Insulin Resistance and Cardiovascular Risk Factors: Multiple Potential Mechanisms of Actions

Epidemiological and clinical studies have indicated that nut consumption could be a healthy dietary strategy to prevent and treat type 2 diabetes (T2DM) and related cardiovascular disease (CVD). The objective of this review is to examine the potential mechanisms of action of nuts addressing effects on glycemic control, weight management, energy balance, appetite, gut microbiota modification, lipid metabolism, oxidative stress, inflammation, endothelial function and blood pressure with a focus on data from both animal and human studies. The favourable effects of nuts could be explained by the unique nutrient composition and bioactive compounds in nuts. Unsaturated fatty acids (monounsaturated fatty acids and polyunsaturated fatty acids) present in nuts may play a role in glucose control and appetite suppression. Fiber and polyphenols in nuts may also have an anti-diabetic effect by altering gut microbiota. Nuts lower serum cholesterol by reduced cholesterol absorption, inhibition of HMG-CoA reductase and increased bile acid production by stimulation of 7-α hydroxylase. Arginine and magnesium improve inflammation, oxidative stress, endothelial function and blood pressure. In conclusion, nuts contain compounds that favourably influence glucose homeostasis, weight control and vascular health. Further investigations are required to identify the most important mechanisms by which nuts decrease the risk of T2DM and CVD.

Influence of different intravenous lipid emulsions on growth, development and laboratory and clinical outcomes in hospitalised paediatric patients: A systematic review

BACKGROUND & AIMS

Fats in the form of lipid emulsions (LEs) are an integral part of intravenous nutrition. The fatty acid composition of different LEs varies. The exact composition of a LE may influence cell and tissue function and clinical outcome. Currently, it is not clear which LE might be best for paediatric patients. We conducted a systematic review of the effects of different intravenous LEs in hospitalised paediatric patients.

METHODS

Randomised controlled trials published in a peer reviewed journal, written in the English language, and comparing two or more different intravenous LEs in hospitalised paediatric patients were included. Data on outcomes of relevance (growth, development, laboratory and clinical outcomes) were extracted, collated and interpreted.

RESULTS

Thirty-one articles involving 1522 infants or children were included. Most outcomes were not affected by the nature of the LE used. LEs containing fish oil, a source of omega-3 fatty acids, improved outcome of retinopathy of prematurity, decreased liver cholestasis and increased blood omega-3 fatty acid levels. LEs containing olive oil increased blood oleic acid level and had a cholesterol lowering effect.

CONCLUSION

Blood fatty acids are influenced by the nature of the intravenous LE used in hospitalised paediatric patients. Most studies suggest limited differences in relevant laboratory or clinical outcomes or in growth in paediatric patients receiving different LEs, although several studies do find benefits from including fish oil or olive oil. There is a need for larger trials to fully evaluate the effects of the available LE types in hospitalised paediatric patients.

A Mediterranean diet lowers blood pressure and improves endothelial function: results from the MedLey randomized intervention trial

Background: The consumption of a Mediterranean diet (MedDiet) is associated with a lower risk of cardiovascular disease. However, its impact on blood pressure and endothelial function is not clear.Objective: We sought to determine the effects of adhering to the consumption of a MedDiet for 6 mo on blood pressure and endothelial function in older, healthy Australians.Design: A total of 166 men and women aged >64 y were allocated via minimization to consume either a MedDiet (n = 85) or their habitual diet (HabDiet; control: n = 81) for 6 mo. The MedDiet comprised mainly plant foods, abundant extra-virgin olive oil, and minimal red meat and processed foods. A total of 152 participants commenced the study, and 137 subjects completed the study. Home blood pressure was measured on 5 consecutive days at baseline (n = 149) and at 3 and 6 mo. Endothelial function (n = 82) was assessed by flow-meditated dilatation (FMD) at baseline and 6 mo. Dietary intake was monitored with the use of 3-d weighed food records. Data were analyzed with the use of linear mixed-effects models to determine adjusted between-group differences.Results: The MedDiet adherence score increased significantly in the MedDiet group but not in the HabDiet group (P < 0.001). The MedDiet, compared with the HabDiet, resulted in lower systolic blood pressure (P-diet × time interaction = 0.02) [mean: -1.3 mm Hg (95% CI: -2.2, -0.3 mm Hg; P = 0.008) at 3 mo and -1.1 mm Hg (95% CI: -2.0, -0.1 mm Hg; P = 0.03) at 6 mo]. At 6 mo, the percentage of FMD was higher by 1.3% (95% CI: 0.2%, 2.4%; P = 0.026) in the MedDiet group.Conclusion: Australian men and women who consumed a MedDiet for 6 mo had small but significantly lower systolic blood pressure and improved endothelial function. This trial was registered at www.anzctr.org.au as ACTRN12613000602729.

Health benefits and evaluation of healthcare cost savings if oils rich in monounsaturated fatty acids were substituted for conventional dietary oils in the United States

The impact of nutritional behaviors on health is beyond debate and has the potential to affect the economic outputs of societies in significant ways. Dietary fatty acids have become a central theme in nutrition research in recent years, and the popularity of dietary oils rich in healthy fatty acids, such as monounsaturated fatty acid (MUFA), for cooking applications and use in food products has increased. Here, the objective is to summarize the health effects of MUFA-rich diets and to systematically estimate the potential healthcare and societal cost savings that could be realized by increasing MUFA intakes compared with other dietary fat intakes in the United States. Using a scoping review approach, the literature of randomized controlled clinical trials was searched and a 4-step cost-of-illness analysis was developed, which included estimates of success rate, disease biomarker reduction, disease incidence reduction, and cost savings. Findings revealed improvements in established biomarkers and in incidence of coronary heart disease and type 2 diabetes, along with potentially substantial annual healthcare and societal cost savings when recommendations for daily MUFA intake were followed. In summary, beyond the beneficial health effects of MUFA-rich diets, potential economic benefits suggest practical implications for consumers, food processors, and healthcare authorities alike.

Emu oil decreases atherogenic plaque formation in cafeteria diet-induced obese rats

BACKGROUND

Atherosclerosis-induced coronary heart disease - caused by elevated levels of low-density lipoproteins (LDL) and inflammation - is one of the most prevalent diseases. Monounsaturated fatty acids are reported to prevent atherosclerosis; emu oil is a rich source of monounsaturated fatty acid, and we hypothesize that emu oil supplementation could lower inflammation and prevent atherosclerosis in diet-induced obese (DIO) animals. Male Wistar rats were randomly divided into five groups (n = 6), and fed with normal diet (chow pellet; ND), or with cafeteria diet (CD), or with CD along with emu oil supplementation at three different doses: ED1 (2 mL), ED2 (4 mL) and ED3 (8 mL) kg(-1) body weight (BW), respectively.

RESULTS

After 12 weeks, the animals were sacrificed and serum was analysed for measuring lipid profile, C-reactive proteins, testosterone and luteinizing hormone. Histopathological studies were performed to observe atherogenic changes in thoracic aorta. Restoration of altered lipid and hormonal profiles, and inhibition of atherogenic changes in thoracic aorta, were observed with supplementation of emu oil, confirming its anti-atherosclerotic activity.

CONCLUSION

The high content of oleic acid in emu oil could have orchestrated - either solely or in combination with linoleic and linolenic acids - causing the upregulation of testosterone biosynthesis and inhibition of atheromatous plaque formation in diet-induced obese animals. © 2015 Society of Chemical Industry.

The interaction between ApoA2 -265T>C polymorphism and dietary fatty acids intake on oxidative stress in patients with type 2 diabetes mellitus

INTRODUCTION

Apolipoprotein A2 (APOA2) -265T>C polymorphism has been studied in relation to oxidative stress and various dietary fatty acids. Since the interaction between APOA2 polymorphism and dietary fatty acids on oxidative stress has not yet discussed, we aimed to investigate the interaction on oxidative stress in type 2 diabetes mellitus (T2DM) patients.

METHODS

The subjects were 180 T2DM patients with known APOA2 genotype, either TT, TC or CC. Superoxide dismutase (SOD) activity was determined by colorimetric method. Total antioxidant capacity (TAC) and serum level of 8-isoprostane F2α were measured by spectrophotometry and ELISA, respectively. Dietary intake was collected through a food frequency questionnaire. Based on the median intake, fatty acids intake was dichotomized into high or low groups. The interaction between APOA2 polymorphism and dietary fatty acids intake was analyzed by ANCOVA multivariate interaction model.

RESULTS

Higher than median intake of omega-6 polyunsaturated fatty acids (n-6 PUFA) was associated with increased serum level of 8-isoprostane F2α in subjects with TT/TC genotype (p = 0.004), and higher than median intake of omega-3 polyunsaturated fatty acids (n-3 PUFA) was associated with increased serum SOD activity in CC genotype (p < 0.001). There was a statistically significant interaction between APOA2 polymorphism and n-6 PUFA intake on 8-isoprostane F2α concentration as well as n-3 PUFA intake on serum SOD activity (p-interaction = 0.04 and 0.02, respectively).

CONCLUSIONS

The current study shows the interaction between APOA2 polymorphism and dietary fatty acids intake on oxidative stress. More investigations on different populations are required to confirm the interaction.

Effects of dietary extra virgin olive oil and its fractions on antioxidant status and DNA damage in the heart of rats co-exposed to aluminum and acrylamide

Oxidative stress generated by an excessive production of free radicals has been linked to the development of several health problems such as cardiovascular diseases. We investigated the protective efficacy of Extra Virgin Olive Oil (EVOO) and its lipophilic fraction (OOLF) and hydrophilic fraction (OOHF) against the cardiotoxicity and DNA damage induced by co-exposure to aluminum (AlCl3) and acrylamide (ACR). Rats were divided into eight groups of six each: controls, AlCl3 (50 mg per kg body weight) administered via drinking water and ACR (20 mg per kg body weight) given by gavage, combined group plus EVOO (300 μl); combined group plus the hydrophilic fraction (1 ml); combined group plus the lipophilic fraction (300 μl); extra virgin olive oil (EVOO) and its fractions were administered daily by gavage for 21 days. Three other groups, considered as positive controls, received either EVOO, OOLF or OOLH. Exposure of rats to both AlCl3 and ACR provoked oxidative stress objectified by an increase in MDA, AOPP and a decrease in GSH, NPSH and vitamin C levels. The activities of CAT, GPx and SOD were also decreased. EVOO and its OOLF fraction exhibited a pronounced enhancement of antioxidant status while a partial recovery in the antioxidant status was obtained with the OOHF fraction. Plasma LDH and CK activities, TC, LDL-C levels, TC/HDL-C and LDL-C/HDL-C ratios were increased, while HDL-C and TG decreased in rats treated with both AlCl3 and ACR. Co-administration of EVOO, OOLF or OOHF to treated rats restored cardiac biomarkers and lipid profile to near-normal values. Histological studies and DNA damage confirmed the biochemical parameters and the beneficial role of EVOO and its two fractions. Our results suggest that extra virgin olive oil and its two fractions can decrease the frequency of cardiac complications and genotoxicity.

Omega 6 fatty acids for the primary prevention of cardiovascular disease

BACKGROUND

Omega 6 plays a vital role in many physiological functions but there is controversy concerning its effect on cardiovascular disease (CVD) risk. There is conflicting evidence whether increasing or decreasing omega 6 intake results in beneficial effects.

OBJECTIVES

The two primary objectives of this Cochrane review were to determine the effectiveness of:1. Increasing omega 6 (Linoleic acid (LA), Gamma-linolenic acid (GLA), Dihomo-gamma-linolenic acid (DGLA), Arachidonic acid (AA), or any combination) intake in place of saturated or monounsaturated fats or carbohydrates for the primary prevention of CVD.2. Decreasing omega 6 (LA, GLA, DGLA, AA, or any combination) intake in place of carbohydrates or protein (or both) for the primary prevention of CVD.

SEARCH METHODS

We searched the following electronic databases up to 23 September 2014: the Cochrane Central Register of Controlled Trials (CENTRAL) on the Cochrane Library (Issue 8 of 12, 2014); MEDLINE (Ovid) (1946 to September week 2, 2014); EMBASE Classic and EMBASE (Ovid) (1947 to September 2014); Web of Science Core Collection (Thomson Reuters) (1990 to September 2014); Database of Abstracts of Reviews of Effects (DARE) and Health Technology Assessment Database, and Health Economics Evaluations Database on the Cochrane Library (Issue 3 of 4, 2014). We searched trial registers and reference lists of reviews for further studies. We applied no language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of interventions stating an intention to increase or decrease omega 6 fatty acids, lasting at least six months, and including healthy adults or adults at high risk of CVD. The comparison group was given no advice, no supplementation, a placebo, a control diet, or continued with their usual diet. The outcomes of interest were CVD clinical events (all-cause mortality, cardiovascular mortality, non-fatal end points) and CVD risk factors (changes in blood pressure, changes in blood lipids, occurrence of type 2 diabetes). We excluded trials involving exercise or multifactorial interventions to avoid confounding.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, extracted the data, and assessed the risk of bias in the included trials.

MAIN RESULTS

We included four RCTs (five papers) that randomised 660 participants. No ongoing trials were identified. All included trials had at least one domain with an unclear risk of bias. There were no RCTs of omega 6 intake reporting CVD clinical events. Three trials investigated the effect of increased omega 6 intake on lipid levels (total cholesterol, low density lipoprotein (LDL-cholesterol), and high density lipoprotein (HDL-cholesterol)), two trials reported triglycerides, and two trials reported blood pressure (diastolic and systolic blood pressure). Two trials, one with two relevant intervention arms, investigated the effect of decreased omega 6 intake on blood pressure parameters and lipid levels (total cholesterol, LDL-cholesterol, and HDL-cholesterol) and one trial reported triglycerides. Our analyses found no statistically significant effects of either increased or decreased omega 6 intake on CVD risk factors.Two studies were supported by funding from the UK Food Standards Agency and Medical Research Council. One study was supported by Lipid Nutrition, a commercial company in the Netherlands and the Dutch Ministry of Economic Affairs. The final study was supported by grants from the Finnish Food Research Foundation, Finnish Heart Research Foundation, Aarne and Aili Turnen Foundation, and the Research Council for Health, Academy of Finland.

AUTHORS' CONCLUSIONS

We found no studies examining the effects of either increased or decreased omega 6 on our primary outcome CVD clinical endpoints and insufficient evidence to show an effect of increased or decreased omega 6 intake on CVD risk factors such as blood lipids and blood pressure. Very few trials were identified with a relatively small number of participants randomised. There is a need for larger well conducted RCTs assessing cardiovascular events as well as cardiovascular risk factors.

Functional Roles of Fatty Acids and Their Effects on Human Health

A variety of fatty acids exists in the diet of humans, in the bloodstream of humans, and in cells and tissues of humans. Fatty acids are energy sources and membrane constituents. They have biological activities that act to influence cell and tissue metabolism, function, and responsiveness to hormonal and other signals. The biological activities may be grouped as regulation of membrane structure and function; regulation of intracellular signaling pathways, transcription factor activity, and gene expression; and regulation of the production of bioactive lipid mediators. Through these effects, fatty acids influence health, well-being, and disease risk. The effects of saturated, cis monounsaturated, ω-6 and ω-3 polyunsaturated, and trans fatty acids are discussed. Although traditionally most interest in the health impact of fatty acids related to cardiovascular disease, it is now clear that fatty acids influence a range of other diseases, including metabolic diseases such as type 2 diabetes, inflammatory diseases, and cancer. Scientists, regulators, and communicators have described the biological effects and the health impacts of fatty acids according to fatty acid class. However, it is now obvious that within any fatty acid class, different members have different actions and effects. Thus, it would seem more appropriate to describe biological effects and health impacts of individual named fatty acids, although it is recognized that this would be a challenge when communicating outside of an academic environment (eg, to consumers).

Anti-inflammatory properties of blended edible oil with synergistic antioxidants

BACKGROUND

Blending of oil combines the potency of two edible oils and offers a balance of fatty acids. Various cooking preparations existing across different ethnicities and regions subject oil to different cooking temperatures thereby causing deterioration of the oil due to oxidative stress. In order to prevent the oxidative damage of unsaturated fatty acid, a blend of rice bran oil (RBO) and safflower oil (SO) (70:30) with an antioxidant technology was designed. A controlled trial was carried out to assess the efficacy of the blend on different biomarkers including lipid parameters and some important inflammatory markers that have the potency to lead to various lifestyle diseases.

STUDY DESIGN

A prospective, double-blind, randomized, parallel group study (on 80 adult hyperlipidemic patients) was conducted for 3 months. During the study, all the subjects were recommended lifestyle modifications, which included, exercise regime and diet counseling; oil quantity consumed was 1 L/person/month for both the groups. The subjects were divided into two groups; one group, continued with their regularly consumed oil whereas, the other was given the test oil. Biomarkers assessed were lipid profile and seven other inflammatory markers were assessed.

RESULTS

Low-density lipoprotein cholesterol (LDL-C) the primary marker for cardiovascular diseases showed a decrease of 56.07 ± 04.31 mg/dL and 31.98 ± 03.81 mg/dL (P < 0.001 by analysis of variance [ANOVA]) from baseline in test and control group, respectively, during 3 months. Similar reduction trends were observed for total cholesterol where -52.31 ± 13.04 mg/dL and 31.98 ± 04.12 mg/dL (P < 0.001 by ANOVA, between the groups) were seen in test and control group, respectively. Oxidized LDL and high sensitivity C-reactive protein showed a reduction of 2.23 ± 1.3 units/dL and 0.87 ± 2.85 mg/L in test group whereas; an increase of 1.04 ± 1.73 units/dL and 0.44 ± 2.37 mg/L was seen in the control group, respectively (P < 0.05 by Student's t-test, between the groups).

CONCLUSION

The study showed that the blend of RBO and SO with antioxidant technology along with other lifestyle changes helps lowering of blood lipids and stated inflammatory biomarkers and thus, in turn may help prevent lifestyle diseases.

Dietary interventions (plant sterols, stanols, omega-3 fatty acids, soy protein and dietary fibers) for familial hypercholesterolaemia

BACKGROUND

A cholesterol-lowering diet and several other dietary interventions have been suggested as a management approach either independently or as an adjuvant to drug therapy in children and adults with familial hypercholesterolaemia (FH). However, a consensus has yet to be reached on the most appropriate dietary treatment. Plant sterols are commonly used in FH although patients may know them by other names like phytosterols or stanols.

OBJECTIVES

To examine whether a cholesterol-lowering diet is more effective in reducing ischaemic heart disease and lowering cholesterol than no dietary intervention in children and adults with familial hypercholesterolaemia. Further, to compare the efficacy of supplementing a cholesterol-lowering diet with either omega-3 fatty acids, soya proteins, plant sterols or plant stanols.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Inborn Errors of Metabolism Trials Register, which is compiled from electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL) (updated with each new issue of The Cochrane Library), quarterly searches of MEDLINE and the prospective handsearching of one journal - Journal of Inherited Metabolic Disease. Most recent search of the Group's Inborn Errors of Metabolism Trials Register: 22 August 2013. We also searched PubMed to 05 February 2012.

SELECTION CRITERIA

Randomised controlled trials, both published and unpublished, where a cholesterol-lowering diet in children and adults with familial hypercholesterolaemia has been compared to other forms of dietary treatment or to no dietary intervention were included.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the trial eligibility and risk of bias and one extracted the data, with independent verification of data extraction by a colleague.

MAIN RESULTS

In the 2014 update of the review, 15 trials have been included, with a total of 453 participants across seven comparison groups. The included trials had either a low or unclear risk of bias for most of the parameters used for risk assessment. Only short-term outcomes could be assessed due to the short duration of follow up in the included trials. None of the primary outcomes, (incidence of ischaemic heart disease, number of deaths and age at death) were evaluated in any of the included trials. No significant differences were noted for the majority of secondary outcomes for any of the planned comparisons. However, a significant difference was found for the following comparisons and outcomes: for the comparison between plant sterols and cholesterol-lowering diet (in favour of plant sterols), total cholesterol levels, mean difference 0.30 mmol/l (95% confidence interval 0.12 to 0.48); decreased serum LDL cholesterol, mean difference -0.60 mmol/l (95% CI -0.89 to -0.31). Fasting serum HDL cholesterol levels were elevated, mean difference -0.04 mmol/l (95% CI -0.11 to 0.03) and serum triglyceride concentration was reduced, mean difference -0.03 mmol/l (95% CI -0.15 to -0.09), although these changes were not statistically significant. Similarly, guar gum when given as an add on therapy to bezafibrate reduced total cholesterol and LDL levels as compared to bezafibrate alone.

AUTHORS' CONCLUSIONS

No conclusions can be made about the effectiveness of a cholesterol-lowering diet, or any of the other dietary interventions suggested for familial hypercholesterolaemia, for the primary outcomes: evidence and incidence of ischaemic heart disease, number of deaths and age at death,due to the lack of data on these. Large, parallel, randomised controlled trials are needed to investigate the effectiveness of a cholesterol-lowering diet and the addition of omega-3 fatty acids, plant sterols or stanols, soya protein, dietary fibers to a cholesterol-lowering diet.

Effect of Smoking on Metalloproteinases (MMPs) Activity in Patients with Acute Myocardial Infarction (AMI)

INTRODUCTION

Many risk factors are involved in the course and pathogenesis of Acute Myocardial Infarction (AMI). Smoking can significantly increase the AMI mortality and morbidity. Matrix metalloproteinases (MMPs), a class of Zn containing enzymes, are involved in the erosion of the fibrous cap and rupture of the plaque which leads to AMI.

AIM

To evaluate the activity of MMP2 and MMP9 in AMI patients, with or without the habit of smoking.

MATERIALS AND METHODS

The study group consists of 300 AMI patients and 100 sex and age matched control subjects with and without the habit of smoking. MMP2 and MMP9 activities were measured in the blood samples of these patients and controls by sandwich enzyme immunoassay and the values were noted and compared.

RESULTS

Both MMP2 and MMP9 were found to be significantly elevated in all the AMI patients when compared to the normal controls subjects irrespective of the habit of smoking. However MMP9 showed a significant elevation when compared to MMP2 in patients with the habit of smoking.

CONCLUSION

The results of the present study shows increased concentration of both MMPs in AMI patients. However, concentration of MMP9 was found to be more in patients with the habit of smoking when compared to MMP2, indicating that smoking can increase the activity of MMP9 in these patients. Hence apart from producing the free radicals, the smoke can increase the activities of matrix degrading enzymes which in turn contribute to the vulnerability of plaque.

Thyroid hormones and antioxidant systems: focus on oxidative stress in cardiovascular and pulmonary diseases

In previous works we demonstrated an inverse correlation between plasma Coenzyme Q₁₀ (CoQ₁₀) and thyroid hormones; in fact, CoQ₁₀ levels in hyperthyroid patients were found among the lowest detected in human diseases. On the contrary, CoQ₁₀ is elevated in hypothyroid subjects, also in subclinical conditions, suggesting the usefulness of this index in assessing metabolic status in thyroid disorders. A Low-T3 syndrome is a condition observed in several chronic diseases: it is considered an adaptation mechanism, where there is a reduction in pro-hormone T4 conversion. Low T3-Syndrome is not usually considered to be corrected with replacement therapy. We review the role of thyroid hormones in regulation of antioxidant systems, also presenting data on total antioxidant capacity and Coenzyme Q₁₀. Published studies suggest that oxidative stress could be involved in the clinical course of different heart diseases; our data could support the rationale of replacement therapy in low-T3 conditions.

NMR protocol for determination of oxidation susceptibility of serum lipids and application of the protocol to a chocolate study

A protocol for determination of oxidation susceptibility of serum lipids based on proton nuclear magnetic resonance ((1)H NMR) spectroscopy is presented and compared to the commonly used spectrophotometric method. Even though there are methodological differences between these two methods, the NMR-based oxidation susceptibility correlates well (r(2) = 0.73) with the lag time determined spectrophotometrically. In addition to the oxidizability of serum lipids, the NMR method provides also information about the lipid profile. The NMR oxidation assay was applied to the chocolate study including fasting serum samples (n = 45) from subjects who had consumed white (WC), dark (DC) or high-polyphenol chocolate (HPC) daily for 3 weeks. The oxidation susceptibility of serum lipids decreased in the HPC group, and there was a significant difference between the WC and HPC groups (P = 0.031). According to the random forest analysis, the consumption of the HPC chocolate induced changes to the amounts of HDL, phosphatidylcholine, sphingomyelin, and nervonic, docosahexaenoic and myristic acids. Furthermore, arachidonic, docosahexaenoic, docosapentaenoic and palmitic acids, gamma-glutamyl transferase, hemoglobin, HDL, phosphatidylcholine and choline containing phospholipids explained about 60% of the oxidation susceptibility values. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11306-011-0323-2) contains supplementary material, which is available to authorized users.

Oxidative stress and heart failure in altered thyroid States

Increased or reduced action of thyroid hormone on certain molecular pathways in the heart and vasculature causes relevant cardiovascular derangements. It is well established that hyperthyroidism induces a hyperdynamic cardiovascular state, which is associated with a faster heart rate, enhanced left ventricular systolic and diastolic function whereas hypothyroidism is characterized by the opposite changes. Hyperthyroidism and hypothyroidism represent opposite clinical conditions, albeit not mirror images. Recent experimental and clinical studies have suggested the involvement of ROS tissue damage under altered thyroid status. Altered-thyroid state-linked changes in heart modify their susceptibility to oxidants and the extent of the oxidative damage they suffer following oxidative challenge. Chronic increase in the cellular levels of ROS can lead to a catastrophic cycle of DNA damage, mitochondrial dysfunction, further ROS generation and cellular injury. Thus, these cellular events might play an important role in the development and progression of myocardial remodeling and heart failure in altered thyroid states (hypo- and hyper-thyroidism). The present review aims at elucidating the various signaling pathways mediated via ROS and their modulation under altered thyroid state and the possibility of antioxidant therapy.

Effects of olive oil and its fractions on oxidative stress and the liver's fatty acid composition in 2,4-Dichlorophenoxyacetic acid-treated rats

Background

Olive oil's beneficial effects are not only related to its high content of oleic acid, but also to the antioxidant potential of its polyphenols. In this study, we assess the effects of virgin olive oil and its fractions on 2,4-D- induced oxidative damage in the liver of rats.

Methods

Male Wistar rats were randomly divided into eight groups of ten each: (C) a control group, (D) group that received 2,4-D (5 mg/kg b.w.), (D/EVOO) group treated with 2,4-D plus extra virgin olive oil, (D/OOHF) group that received 2,4-D plus hydrophilic fraction, (D/OOLF) group treated with 2,4-D plus lipophilic fraction, (EVOO) group that received only extra virgin olive oil, (OOHF) group given hydrophilic fraction and (OOLF) group treated with lipophilic fraction. These components were daily administered by gavage for 4 weeks.

Results

A significant liver damage was observed in rats treated with 2,4-D via increased serum levels of transaminases and alkaline phosphatase, hepatic lipid peroxidation and decreased hepatic antioxidant enzyme activities, namely, superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase. The liver's fatty acid composition was also significantly modified with 2,4-D exposure. However, extra virgin olive oil and hydrophilic fraction intake during 2,4-D treatment induced a significant increase in the antioxidant enzyme activities and a decrease in the conjugated dienes (CD) and thiobarbituric acid-reactive substances (TBARs) levels in the liver. The lipophilic fraction supplemented to 2,4-D- treated rats did not show any improvement in the liver oxidative status while a marked improvement was detected in the hepatic fatty acid composition of rats supplemented with olive oil and the two fractions.

Conclusion

We concluded that the protective effect of olive oil against oxidative damage induced by 2,4-D is mainly related to the antioxidant potential of its hydrophilic fraction.

Dietary olive oil effect on antioxidant status and fatty acid profile in the erythrocyte of 2,4-D- exposed rats

Background

Oxidative stress produced by reactive oxygen species (ROS) has been linked to the development of several diseases such as cardiovascular, cancer, and neurodegenerative diseases. This study investigates the possible protective effect of extra virgin olive oil (EVOO), lipophilic fraction (OOLF) and hydrophilic fraction (OOHF) on oxidative stress and fatty acid profile of erythrocytes in 2,4-D treated rats.

Methods

Male Wistar rats were divided randomly into eight groups: control (C), (2,4-D) at a dose of 5 mg/kg b.w., (2,4-D/EVOO) was given 2,4-D plus EVOO, (2,4-D/OOHF) that received 2,4-D plus hydrophilic fraction, (2,4-D/OOLF) treated with 2,4-D plus lipophilic fraction, (EVOO) that received only EVOO, (OOHF) was given hydrophilic fraction and (OOLF) treated with lipophilic fraction. These components were daily administered by gavages for 4 weeks.

Results

2,4-D treatment lead to decrease of antioxidant enzyme activities, namely, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) associated with a higher amount of MDA level. Erythrocyte membranes' fatty acid composition was also significantly modified with 2,4-D exposure. EVOO and hydrophilic fraction supplemented to rats with or not 2,4-D treatment enhanced the antioxidant enzyme activities and reduced the MDA level. However, lipophilic fraction did not show any improvement in oxidative damage induced by 2,4-D in spite its richness in MUFA and vitamins.

Conclusion

EVOO administered to 2,4-D-treated rats protected erythrocyte membranes against oxidative damage by means of preventing excessive lipid peroxidation to increase the MUFA composition and increase maintaining antioxidants enzymes at normal concentrations.

n-6 Fatty acids and cardiovascular health: a review of the evidence for dietary intake recommendations

n-6 PUFA are well known for their critical role in many physiological functions and seem to reduce risks of CHD. However, some argue that excessive consumption of n-6 PUFA may lead to adverse effects on health and therefore recommend reducing dietary n-6 PUFA intake or fixing an upper limit. In this context, the present work aimed to review evidence on the link between n-6 PUFA and risks of CVD. Epidemiological studies show that n-6 PUFA dietary intake significantly lowers blood LDL-cholesterol levels. In addition, n-6 PUFA intake does not increase several CVD risk factors such as blood pressure, inflammatory markers, haemostatic parameters and obesity. Data from prospective cohort and interventional studies converge towards a specific protective role of dietary n-6 PUFA intake, in particular linoleic acid, against CVD. n-6 PUFA benefits are even increased when SFA intake is also reduced. In regards to studies examined in this narrative review, recommendation for n-6 PUFA intake above 5 %, and ideally about 10 %, of total energy appears justified.

Individual variation and intraclass correlation in arachidonic acid and eicosapentaenoic acid in chicken muscle

Chicken meat with reduced concentration of arachidonic acid (AA) and reduced ratio between omega-6 and omega-3 fatty acids has potential health benefits because a reduction in AA intake dampens prostanoid signaling, and the proportion between omega-6 and omega-3 fatty acids is too high in our diet. Analyses for fatty acid determination are expensive, and finding the optimal number of analyses to give reliable results is a challenge. The objective of the present study was i) to analyse the intraclass correlation of different fatty acids in five meat samples, of one gram each, within the same chicken thigh, and ii) to study individual variations in the concentrations of a range of fatty acids and the ratio between omega-6 and omega-3 fatty acid concentrations among fifteen chickens. Fifteen newly hatched broilers were fed a wheat-based diet containing 4% rapeseed oil and 1% linseed oil for three weeks. Five muscle samples from the mid location of the thigh of each chicken were analysed for fatty acid composition. The intraclass correlation (sample correlation within the same animal) was 0.85-0.98 for the ratios of total omega-6 to total omega-3 fatty acids and of AA to eicosapentaenoic acid (EPA). This indicates that when studying these fatty acid ratios, one sample of one gram per animal is sufficient. However, due to the high individual variation between chicken for these ratios, a relatively high number of animals (minimum 15) are required to obtain a sufficiently high power to reveal significant effects of experimental factors (e.g. feeding regimes). The present experiment resulted in meat with a favorable concentration ratio between omega-6 and omega-3 fatty acids. The AA concentration varied from 1.5 to 2.8 g/100 g total fatty acids in thigh muscle in the fifteen broilers, and the ratio between AA and EPA concentrations ranged from 2.3 to 3.9. These differences among the birds may be due to genetic variance that can be exploited by breeding for lower AA concentration and/or a more favorable AA/EPA ratio to produce meat with health benefits.

Dietary treatment for familial hypercholesterolaemia

BACKGROUND

A cholesterol-lowering diet and several other dietary interventions have been suggested as a management approach either independently or as an adjuvant to drug therapy in children and adults with familial hypercholesterolemia. However, a consensus has yet to be reached on the most appropriate dietary treatment.

OBJECTIVES

To examine whether a cholesterol-lowering diet is more effective in reducing ischaemic heart disease and lowering cholesterol than no dietary intervention in children and adults with familial hypercholesterolaemia. Further, to compare the efficacy of supplementing a cholesterol-lowering diet with either omega-3 fatty acids, soya proteins, plant sterols or plant stanols.

SEARCH STRATEGY

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Inborn Errors of Metabolism Trials Register.Most recent search of the Group's Inborn Errors of Metabolism Trials Register: 09 October 2009.We also searched PubMed till 01 June 2008.

SELECTION CRITERIA

Randomised controlled trials, both published and unpublished, where a cholesterol-lowering diet in children and adults with familial hypercholesterolaemia has been compared to other forms of dietary treatment or to no dietary intervention were included.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the trial eligibility and methodological quality and one extracted the data, with independent verification of data extraction by a colleague.

MAIN RESULTS

In the present update, four new trials have been added making eleven trials with a total of 331 participants eligible for inclusion. Only short-term outcomes could be assessed due to the short duration of follow up in the included studies. None of the primary outcomes, (incidence of ischaemic heart disease, number of deaths and age at death) were evaluated in any of the included studies. No significant difference was noted for the majority of secondary outcomes for any of the planned comparisons. However, a significant difference was found only for the following comparison and outcome: total cholesterol levels for the comparison between plant sterols and cholesterol-lowering diet, mean difference 0.70 (95% confidence interval 0.19 to 1.21).

AUTHORS' CONCLUSIONS

No conclusions can be made about the effectiveness of a cholesterol-lowering diet, or any of the other dietary interventions suggested for familial hypercholesterolaemia, due to the lack of adequate data. Large, parallel, randomised controlled trials are needed to investigate the effectiveness of a cholesterol-lowering diet and the addition of omega-3 fatty acids, plant sterols or stanols, soya protein to a cholesterol-lowering diet.

Long-chainn-3 polyunsaturated fatty acid from fish oil modulates aortic nitric oxide and tocopherol status in the rat

In spite of their high oxidisability, long-chainn-3 PUFA protect against CVD. Dietary fatty acids modulate the fatty acid composition of lipoproteins involved in atherosclerosis. We thought that if long-chainn-3 PUFA were able to increase NO production by the aorta, then by its antioxidant activity the NO will prevent lipid peroxidation. However, the beneficial effect of NOin vivoon VLDL+LDL oxidation would only be possible if NO could diffuse to their lipidic core. Rats were fed maize oil- or fish oil as menhaden oil- (MO) rich diets for 8 weeks, to study the effects of MO on aortic NO production, NO diffusion into VLDL+LDL, the extent of oxidation in native VLDL+LDL and their oxidisabilityex vivo. Aortic NO production and its α-tocopherol content were increased andn-3 PUFA were incorporated into the VLDL+LDL. In spite of the higher peroxidisability and the low α-tocopherol in native VLDL+LDL from rats fed MO, native VLDL+LDL from the two groups shared similar electrophoretic patterns, conjugated dienes, thiobarbituric acid-reactive substances, total antioxidant capacity, and NO diffusibility on VLDL+LDL, indicative of anin vivoprotection against oxidation. However, these results do not correlate with theex vivooxidisability of VLDL+LDL, as NO is lacking. Thus, thein vivobeneficial effects can be explained by increased α-tocopherol in aorta and by a compensatory effect of NO on VLDL+LDL against the low α-tocopherol levels, which may contribute to the anti-atherogenic properties of fish oil.

Olive oil and oxidative stress

Oxidative stress is defined as an imbalance between the oxidant and antioxidant systems of the body, in favor of the oxidants. Oxidative stress produced by free radicals has been linked to the development of several diseases such as cardiovascular, cancer, and neurodegenerative diseases Olive oil is the main source of fat of the Mediterranean diet which has been shown to be effective against oxidative stress associated diseases and also with ageing. Besides its richness in monounsaturated fatty acids, the oleic acid, olive oil contains minor components with antioxidant properties. In this review, we summarize the state of the art, and degree of evidence, of the body of knowledge concerning the protective role of the major and minor components of olive oil on oxidative stress.

The phenolic compounds of olive oil: structure, biological activity and beneficial effects on human health

The Mediterranean diet is rich in vegetables, cereals, fruit, fish, milk, wine and olive oil and has salutary biological functions. Epidemiological studies have shown a lower incidence of atherosclerosis, cardiovascular diseases and certain kinds of cancer in the Mediterranean area. Olive oil is the main source of fat, and the Mediterranean diet's healthy effects can in particular be attributed not only to the high relationship between unsaturated and saturated fatty acids in olive oil but also to the antioxidant property of its phenolic compounds. The main phenolic compounds, hydroxytyrosol and oleuropein, which give extra-virgin olive oil its bitter, pungent taste, have powerful antioxidant activity bothin vivoandin vitro. The present review focuses on recent works analysing the relationship between the structure of olive oil polyphenolic compounds and their antioxidant activity. These compounds' possible beneficial effects are due to their antioxidant activity, which is related to the development of atherosclerosis and cancer, and to anti-inflammatory and antimicrobial activity.

Different effects of diets rich in olive oil, rapeseed oil and sunflower-seed oil on postprandial lipid and lipoprotein concentrations and on lipoprotein oxidation susceptibility

Elevated concentrations of fasting and non-fasting triacylglycerol-rich lipoproteins (TRL) as well as oxidative changes of lipoproteins may increase the risk of ischaemic heart disease. To compare the effects of different diets rich in unsaturated fatty acids on the concentrations andin vitrooxidation of fasting and postprandial lipoproteins eighteen males consumed diets enriched with rapeseed oil (RO), olive oil (OO), or sunflower-seed oil (SO) in randomised order for periods of 3 weeks followed by a RO test meal. In the postprandial state the concentrations of cholesterol and triacylglycerol (TAG) in TRL were higher after consumption of OO compared with RO and SO (P<0·04), possibly related to differences in the fasting state. The propagation rates for VLDL and LDL oxidation were higher in the postprandial compared with the fasting state irrespective of diet. In the fasting state, the propagation rates were highest after SO (P<0·001), and in the postprandial state, SO gave rise to a shorter VLDL lag time (P=0·03) and a higher propagation rate than OO consumption (P=0·04). Overall, the SO diet resulted in a higher postprandial propagation rate of LDL (P<0·001) compared with RO and OO, while there was no effect of diet on LDL oxidation lag time. Our results suggest that RO and SO diets lower the postprandial cholesterol and TAG concentrations compared with OO, while RO and OO diets result in similar and lowerin vitrosusceptibility to oxidation of lipoproteins than SO.

Cholesterol-lowering potential in human subjects of fat from pigs fed rapeseed oil

The possibility of achieving blood-lipid-lowering characteristics of pig fat by increasing the content of unsaturated fat in pig feed was evaluated. Three pig feeding regimens were applied: basal feed (no added fat or vitamin E), basal feed + rapeseed oil (60 g/kg feed), and basal feed + rapeseed oil (60 g/kg) + vitamin E (200 mg/kg). Meat and meat products from the three pig groups were incorporated into diets providing 86 g pig fat/10 MJ. The diets were served to twelve healthy human male subjects for 3 weeks each in a randomised crossover design. The diets prepared from pigs fed rapeseed oil had a lower content of saturated fatty acids (approximately 9 v. 11 % of energy) and a higher content of polyunsaturated fatty acids (approximately 6 v. 4 % of energy) than the diet prepared from pigs fed the basal feed. Diets based on fat from pigs fed the rapeseed oil resulted in significantly lower (approximately 4 %, P = 0·019) total serum cholesterol concentration compared with the diet from pigs fed the basal feed. No differences were observed in LDL-, HDL- or VLDL-cholesterol, or in triacylglycerol or VLDL-triacylglycerol concentrations. Addition of vitamin E to the pig feed resulted in only a minor increase in vitamin E content in the human subjects' diet and the vitamin E content was low in all three pig diets. Plasma vitamin E concentration in the human subjects at the end of the period with diets from pigs fed rapeseed oil without vitamin E was significantly lower (P = 0·04) than in the other two diet periods. In conclusion, an increased content of rapeseed oil in pig feed changes the fatty acid composition of the pig fat in a way that has a potential to reduce blood cholesterol concentrations in human subjects. However, intake of pig fat with a higher content of unsaturated fatty acids needs to be matched by a higher dietary intake of vitamin E.

Evolutionary aspects of diet, the omega-6/omega-3 ratio and genetic variation: nutritional implications for chronic diseases

Anthropological and epidemiological studies and studies at the molecular level indicate that human beings evolved on a diet with a ratio of omega-6 to omega-3 essential fatty acids (EFA) of approximately 1 whereas in Western diets the ratio is 15/1 to 16.7/1. A high omega-6/omega-3 ratio, as is found in today's Western diets, promotes the pathogenesis of many diseases, including cardiovascular disease, cancer, osteoporosis, and inflammatory and autoimmune diseases, whereas increased levels of omega-3 polyunsaturated fatty acids (PUFA) (a lower omega-6/omega-3 ratio), exert suppressive effects. Increased dietary intake of linoleic acid (LA) leads to oxidation of low-density lipoprotein (LDL), platelet aggregation, and interferes with the incorporation of EFA in cell membrane phospholipids. Both omega-6 and omega-3 fatty acids influence gene expression. Omega-3 fatty acids have anti-inflammatory effects, suppress interleukin 1beta (IL-1beta), tumor necrosis factor-alpha (TNFalpha) and interleukin-6 (IL-6), whereas omega-6 fatty acids do not. Because inflammation is at the base of many chronic diseases, dietary intake of omega-3 fatty acids plays an important role in the manifestation of disease, particularly in persons with genetic variation, as for example in individuals with genetic variants at the 5-lipoxygenase (5-LO). Carotid intima media thickness (IMT) taken as a marker of the atherosclerotic burden is significantly increased, by 80%, in the variant group compared to carriers with the common allele, suggesting increased 5-LO promoter activity associated with the (variant) allele. Dietary arachidonic acid (AA) and LA increase the risk for cardiovascular disease in those with the variants, whereas dietary intake of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) decrease the risk. A lower ratio of omega-6/omega-3 fatty acids is needed for the prevention and management of chronic diseases. Because of genetic variation, the optimal omega-6/omega-3 fatty acid ratio would vary with the disease under consideration.