Influence of hydrogenated fat and butter on CVD risk factors: remnant-like particles, glucose and insulin, blood pressure and C-reactive protein

Molecular effects of the consumption of margarine and butter varying in trans fat composition: a parallel human intervention study

BACKGROUND

Whereas the dietary intake of industrial trans fatty acids (iTFA) has been specifically associated with inflammation, cardiovascular disease, and type 2 diabetes, understanding the impact of dietary fats on human health remains challenging owing to their complex composition and individual effects of their lipid components on metabolism. The aim of this study is to profile the composition of blood, measured by the fatty acid (FAs) profile and untargeted metabolome of serum and the transcriptome of blood cells, in order to identify molecular signatures that discriminate dietary fat intakes.

METHODS

In a parallel study, the molecular effects of consuming dairy fat containing ruminant TFA (rTFA) or margarine containing iTFA were investigated. Healthy volunteers (n = 42; 45-69 y) were randomly assigned to diets containing margarine without TFA as major source of fat (wTFA control group with 0.4 g TFA per 100 g margarine), margarine with iTFA (iTFA group with 4.1 g TFA per 100 g margarine), or butter with rTFA (rTFA group with 6.3 g TFA per 100 g butter) for 4 weeks. The amounts of test products were individually selected so that fat intake contributed to 30-33% of energy requirements and TFA in the rTFA and iTFA groups contributed to up to 2% of energy intake. Changes in fasting blood values of lipid profiles (GC with flame-ionization detection), metabolome profiles (LC-MS, GC-MS), and gene expression (microarray) were measured.

RESULTS

Eighteen FAs, as well as 242 additional features measured by LC-MS (185) and GC-MS (54) showed significantly different responses to the diets (P_FDR-adjusted < 0.05), mainly distinguishing butter from the margarine diets while gene expression was not differentially affected. The most abundant TFA in the butter, i.e. TFA containing (E)-octadec-11-enoic acid (C18:1 t11; trans vaccenic acid), and margarines, i.e. TFA containing (E)-octadec-9-enoic acid (C18:1 t9; elaidic acid) were reflected in the significantly different serum levels of TFAs measured after the dietary interventions.

CONCLUSIONS

The untargeted serum metabolome differentiates margarine from butter intake although the identification of the discriminating features remains a bottleneck. The targeted serum FA profile provides detailed information on specific molecules differentiating not only butter from margarine intake but also diets with different content of iTFAs in margarine.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00933322.

Inclusion of Sunflower Oil, Organic Selenium, and Vitamin E on Milk Production and Composition, and Blood Parameters of Lactating Cows

Simple Summary

Feeding sunflower oil, selenium, and vitamin E to lactating dairy cows has improved the nutritional profile of milk for human consumption and positively impacted animal performance. This may be attributed to the increased healthier fat components, i.e., “good fats”, and antioxidant substances in milk. This study evaluated the effects of supplementing sunflower oil, selenium, and vitamin E on milk production and composition, and the blood parameters of lactating dairy cows. Supplementing sunflower oil to lactating dairy cows provided beneficial effects on milk fatty acid profiles, increasing healthier fatty acids concentrations, which have been reported as important anticarcinogenic, antiatherogenic, and antidiabetic nutrients in human diet. However, this strategy reduced the milk fat content. Selenium and vitamin E supplementation improved milk production and provided higher selenium and vitamin E content in blood and milk. These compounds are important antioxidants and nutrients for animal and human health.

Abstract

Aiming to improve milk quality and animal health, the effects of the inclusion of sunflower oil with added organic selenium (Se) and vitamin E in the diets of lactating cows were evaluated. Twenty-four multiparous lactating Jersey cows were randomly enrolled into four treatments: CON (control); SEL [2.5 mg organic Se kg⁻¹ dry matter (DM) + 1000 IU vitamin E daily]; SUN (sunflower oil 3% DM); and SEL + SUN (sunflower oil 3% DM + 2.5 mg organic Se kg⁻¹ DM + 1000 IU vitamin E daily). The experimental period was 12 weeks with 14 days for acclimation. Cows were milked twice a day. Dry matter intake, milk production, and composition were measured daily and analyzed in a pooled 4-week sample. On day 84, white blood cell counts, as well as serum and milk Se and vitamin E levels, were assessed. Supplementation with selenium and vitamin E alone or combined with sunflower oil increased milk production, and increased the serum and milk concentrations of those nutrients. The inclusion of sunflower oil reduced fat content and DM intake but also altered the milk fatty acid profile, mainly increasing levels of trans 11 C18:1 (vaccenic) and cis 9 trans 11 conjugated linoleic acid (CLA). Our results indicate that supplementation with sunflower oil, Se and vitamin E provides beneficial effects on animal performance and milk composition, which could be an important source of CLA and antioxidants (Se and vitamin E) for human consumption.

Soybean oil lowers circulating cholesterol levels and coronary heart disease risk, and has no effect on markers of inflammation and oxidation

To reduce risk of coronary heart disease, replacement of saturated fats (SFAs) with polyunsaturated fats (PUFA) is recommended. Strong and concordant evidence supports this recommendation, but controversy remains. Some observational studies have reported no association between SFAs and coronary heart disease, likely because of failure to account for the macronutrient replacing SFAs, which determines the direction and strength of the observed associations. Controversy also persists about whether ω-6 (nω-6) PUFA or a high dietary ratio of nω-6 to ω-3 (nω-3) fatty acids leads to proinflammatory and pro-oxidative states. These issues are relevant to soybean oil, which is the leading edible oil consumed globally and in the United States. Soybean oil accounts for over 40% of the US intake of both essential fatty acids. We reviewed clinical and epidemiologic literature to determine the effects of soybean oil on cholesterol levels, inflammation, and oxidation. Clinical evidence indicates that soybean oil does not affect inflammatory biomarkers, nor does it increase oxidative stress. On the other hand, it has been demonstrated that when dietary SFAs are replaced with soybean oil, blood cholesterol levels are lowered. Regarding the nω-6:nω-3 dietary ratio, health agencies have consistently rejected the importance of this ratio, instead emphasizing the importance of consuming sufficient amounts of each type of fat. Thus, several lines of evidence indicate that soybean oil can positively contribute to overall health and reduction of risk of coronary heart disease.

Structure and thermal properties of beeswax-based oleogels with different types of vegetable oil

Beeswax-based oleogels with different types of vegetable oil, including camellia oil (CO), soybean oil (SO), sunflower oil (SFO), or flaxseed oil (FO), were prepared and their structure and thermal properties were evaluated. The critical concentration of oleogel obtained from each of CO, SO, and SFO at 25 °C was 3% (w/w), and that from FO was 4%. Thermal measurements revealed similar thermodynamic curves for oleogels in different lipid phases. X-Ray diffraction showed orthorhombic perpendicular subcell packing and characteristic peaks of the β’ form. Furthermore, a morphology analysis of the crystals showed that they were needle shaped. Fourier transform-infrared spectra revealed that beeswax-based oleogels were formed via non-covalent bonds and may be stabilized with physical entanglements. The oleogels showed oil type-dependent oxidative abilities, but they were all stable and showed no obvious changes in peroxide value during 90 days of storage at 5 °C.

Erythrocyte membrane fatty acids and breast cancer risk by tumor tissue expression of immuno-inflammatory markers and fatty acid synthase: a nested case-control study

BACKGROUND

Previous studies of fatty acids and breast cancer risk have shown mixed results, which may be due in part to tumor heterogeneity. Prior research has also illustrated an important role of specific fatty acids in immune regulation, T cell function, and inflammation, indicating that the effects of specific fatty acids on breast cancer risk may vary by tumor expression of immuno-inflammatory markers. We therefore aimed to evaluate the relationships between prediagnostic erythrocyte membrane fatty acids and breast cancer risk by tumor tissue expression of immuno-inflammatory markers (CD4, CD8, CD20, CD163, COX-2) and fatty acid synthase (FAS).

METHODS

We conducted a matched case-control study nested within the Nurses' Health Study II (n = 235 cases and 235 controls). Blood samples were collected from 1996 to 1999. Tumor tissue blocks were collected for cases diagnosed after blood collection and through 2006. Unconditional nominal polytomous logistic regression adjusted for matching factors and potential confounders was used to assess whether associations between fatty acids and breast cancer risk varied by tumor expression subtype, ascertained via immunohistochemistry. Odds ratios (OR) and 95% confidence intervals (CI) were estimated separately by tumor expression subtype using unconditional logistic regression.

RESULTS

Associations between fatty acids and breast cancer risk did not vary substantially by tumor CD4, CD20, CD163, or COX-2. However, n-3 polyunsaturated fatty acids (PUFAs) were inversely associated with CD8^low but not CD8^high cancers (CD8^low OR_{T3 vs T1} = 0.45, 95% CI 0.23-0.87, P_trend = 0.02; CD8^high OR_{T3 vs T1} = 1.19, 95% CI 0.62-2.26, P_trend = 0.62; P_het = 0.04). n-6 PUFAs were suggestively inversely associated with CD8^high but not CD8^low cancers (CD8^high OR_{T3 vs T1} = 0.61, 95% CI 0.32-1.14, P_trend = 0.11; CD8^low OR_{T3 vs T1} = 1.63, 95% CI 0.87-3.04, P_trend = 0.12; P_het = 0.02). Trans fatty acids were positively associated with FAS^high but not FAS^low tumors (FAS^high OR_{T3 vs T1} = 2.94, 95% CI 1.46-5.91, P_trend = 0.002; FAS^low OR_{T3 vs T1} = 0.99, 95% CI 0.52-1.92, P_trend = 0.97; P_het = 0.01).

CONCLUSION

Results indicate that the effects of n-3 PUFAs, n-6 PUFAs, and trans fatty acids on breast cancer risk may vary by tumor tissue expression subtypes. Findings suggest potential immuno-modulatory and FAS-mediated mechanisms.

Bioactivity and health effects of ruminant meat lipids. Invited Review

Ruminant meat (RM) is an excellent source of high-quality protein, B vitamins and trace minerals and plays an important role in global food and nutrition security. However, nutritional guidelines commonly recommend reduced intake of RM mainly because of its high saturated fatty acid (SFA) content, and more recently because of its perceived negative environmental impacts. RM is, however, rich in heart healthy cis-monounsaturated fatty acids and can be an important source of long-chain omega-3 (n-3) fatty acids in populations with low fish consumption. In addition, RM is a source of bioactive phospholipids, as well as rumen-derived bioactive fatty acids including branched-chain, vaccenic and rumenic acids, which have been associated with several health benefits. However, the role of bioactive RM lipids in maintaining and improving consumers' health have been generally ignored in nutritional guidelines. The present review examines RM lipids in relation to human health, and evaluates the effectiveness of different feeding strategies and possibilities for future profile and content improvement.

Relationship Between the Consumption of Milk-Based Oils Including Butter and Kermanshah Ghee with Metabolic Syndrome: Ravansar Non-Communicable Disease Cohort Study

BACKGROUND

The prevalence of metabolic syndrome (MetS) in recent years has been growing in different societies, which may be due to lifestyle changes including changes in diet, in particular the consumption pattern of edible oils. The purpose of this study was to investigate the relationship between the consumption of animal oils including butter and Kermanshah ghee with MetS and its components in the adult population of Ravansar Non-Communicable Disease (RaNCD) cohort study.

METHODS

This cross-sectional study was carried out on 5550 adults aged 35-65 years using baseline data of Ravansar's prospective study center in Iran. MetS was defined according to the criteria of modified NCEP ATP III for Iranian adults. Relationship between the consumption of butter and Kermanshah ghee and MetS was analyzed by logistic regression model using STATA software.

RESULTS

In our study, the frequency of MetS was 31.40%. The mean body mass index and mean age were 27.1±4.6 kg/m² and 47.6±8.2 years. The mean values of consumed butter and Kermanshah ghee were 3.3±1.8 and 5.1±2.3 g/day, respectively. After adjusting the confounding variables, the highest to the lowest quintile of butter and Kermanshah ghee consumption showed a reverse correlation with the MetS (OR = 0.7, 95% CI = 0.5-0.9) and (OR= 0.7, 95% CI=0.6-0.9), respectively.

CONCLUSION

This study revealed a reverse relationship between milk and Kermanshah ghee consumption with MetS and its components. Therefore, consumption of milk-based oils may be associated with lower cardiovascular risk factors.

Eighteen‑carbon trans fatty acids and inflammation in the context of atherosclerosis

Endothelial dysfunction is a pro-inflammatory state characterized by chronic activation of the endothelium, which leads to atherosclerosis and cardiovascular disease (CVD). Intake of trans fatty acids (TFAs) is associated with an increased risk of CVD. This risk is usually associated with industrial TFAs (iTFAs) rather than ruminant TFAs (rTFAs); however it is not clear how specific TFA isomers differ in their biological activity and mechanisms of action with regard to inflammation. Here we review the literature on 18‑carbon TFAs, including the research associating their intake or levels with CVD and studies relating 18‑carbon TFA exposure to modulation of inflammatory processes. The evidence associating iTFAs with CVD risk factors is fairly consistent and studies in humans usually show a relation between iTFAs and higher levels of inflammatory markers. In contrast, studies in humans, animals and in vitro suggest that rTFAs have null or mildly beneficial effects in cardiovascular health, metabolic parameters and inflammatory markers, although the evidence is not always consistent. More studies are needed to better identify the beneficial and detrimental effects of the different TFAs, including those with 18 carbons.

Effects of palm oil consumption on biomarkers of glucose metabolism: A systematic review

Introduction

Vegetable oil is an important source of fatty acids, and as palm oil being the highest consumed vegetable oil in many countries, its high saturated fatty acid content has led many concerns on cardiometabolic health. Dietary fatty acids has also been linked to affect glucose metabolism and insulin sensitivity. This systematic review is aimed at critically evaluating the available evidence on the association of palm oil with the biomarkers of glucose metabolism as compared to other vegetable oils.

Methods

We systemically searched PubMed, CENTRAL and Scopus up to June 2018. We searched for published interventional studies on biomarkers of glucose metabolism (defined as fasting glucose, fasting insulin, HOMA, 2-hour post prandial glucose and HbA1C) that compared palm oil- or palm olein-rich diets with other edible vegetable oils (such as olive oil, canola oil and soybean oil). Two reviewers independently extracted data and assessed study risks of bias. Mean differences of outcomes were pooled for the meta-analysis.

Results

We identified 1921 potentially eligible articles with only eight included studies. Seven randomised cross-over trials and one parallel trial were included. Study population were among young to middle-aged, healthy, non-diabetic, and normal weight participants. Intervention duration ranged from three to seven weeks, and fat substitution ranged from 15% to 20% energy. There were insignificant differences in fasting glucose when compared to partially hydrogenated soybean oil [-0.15mmol/L (-0.46,0.16) P = 0.33, I² = 48%], soybean oil [0.05mmol/L (-0.09,0.18) P = 0.49, I² = 0%] and olive oil [0.04mmol/L (-0.09,0.17) P = 0.76, I² = 0%]. Insignificant effects were also seen on fasting insulin when compared to partially hydrogenated soybean oil [1.72pmol/L (-11.39,14.84) P = 0.80, I² = 12%] and olive oil diet [-0.14pmol/L (-4.87,4.59) P = 0.95, I² = 0%].

Conclusion

Current evidence on the effects of palm oil consumption on biomarkers of glucose metabolism is poor and limited to only healthy participants. We conclude that little or no additional benefit will be obtained by replacing palm oil with other oils rich in mono or polyunsaturated fatty acids for changes in glucose metabolism.

Plant-derived polyunsaturated fatty acids and markers of glucose metabolism and insulin resistance: a meta-analysis of randomized controlled feeding trials

The objective of this meta-analysis was to investigate the effects of plant-derived polyunsaturated fatty acids (PUFAs) on glucose metabolism and insulin resistance. Scopus and PubMed databases were searched until January 2018. Eligible studies were randomized controlled feeding trials that investigated the effects of a diet high in plant-derived PUFA as compared with saturated fatty acids (SFA) or carbohydrates and measured markers of glucose metabolism and insulin resistance as outcomes. Data from 13 relevant studies (19 comparisons of plant-derived PUFA with control) were retrieved. Plant-derived PUFA did not significantly affect fasting glucose (-0.01 mmol/L (95 % CI - 0.06 to 0.03 mmol/L)), but lowered fasting insulin by 2.6 pmol/L (-4.9 to -0.2 pmol/L) and homeostatic model assessment-insulin resistance (HOMA-IR) by 0.12 units (-0.23 to - 0.01 units). In dose-response analyses, a 5% increase in energy (En%) from PUFA significantly reduced insulin by 5.8 pmol/L (95% CI -10.2 to -1.3 pmol/L), but not glucose (change -0.07, 95% CI -0.17 to 0.04 mmol/L) and HOMA-IR (change - 0.24, 95% CI -0.56 to 0.07 units). In subgroup analyses, studies with higher PUFA dose (upper tertiles) reduced insulin (-6.7, -10.5 to -2.9 pmol/L) and HOMA-IR (-0.28, -0.45 to -0.12 units), but not glucose (-0.09, 95% CI -0.18 to 0.01 mmol/L), as compared with an isocaloric control. Subgroup analyses showed no differences in effects between SFA and carbohydrates as replacement nutrients (p interaction ≥0.05). Evidence from randomized controlled trials indicated that plant-derived PUFA as an isocaloric replacement for SFA or carbohydrates probably reduces fasting insulin and HOMA-IR in populations without diabetes.

Effects of exchanging carbohydrate or monounsaturated fat with saturated fat on inflammatory and thrombogenic responses in subjects with abdominal obesity: A randomized controlled trial

BACKGROUND & AIMS

Modification of the amount and type of dietary fat has diverse effects on cardiovascular risk.

METHODS

We recruited 54 abdominally obese subjects to participate in a prospective cross-over design, single-blind trial comparing isocaloric 2000 kcal MUFA or carbohydrate-enriched diet with SFA-enriched diet (control). The control diet consisted of 15E% protein, 53E% carbohydrate and 32E% fat (12E% SFA, 13E% MUFA). A total of ∼7E% of MUFA or refined carbohydrate was exchanged with SFA in the MUFA-rich and carbohydrate-rich diets respectively for 6-weeks. Blood samples were collected at fasting upon trial commencement and at week-5 and 6 of each dietary-intervention phase to measure levels of cytokines (IL-6, IL-1β), C-reactive protein (CRP), thrombogenic markers (E-selectin, PAI-1, D-dimer) and lipid subfractions. Radial pulse wave analysis and a 6-h postprandial mixed meal challenge were carried out at week-6 of each dietary intervention. Blood samples were collected at fasting, 15 and 30 min and hourly intervals thereafter till 6 h after a mixed meal challenge (muffin and milkshake) with SFA or MUFA (872.5 kcal, 50 g fat, 88 g carbohydrates) or CARB (881.3 kcal, 20 g fat, 158 g carbohydrates)- enrichment corresponding to the background diets.

RESULTS

No significant differences in fasting inflammatory and thrombogenic factors were noted between diets (P > 0.05). CARB meal was found to increase plasma IL-6 whereas MUFA meal elevated plasma D-dimer postprandially compared with SAFA meal (P < 0.05). Comparing the 3 meals, there were similar postprandial elevations in IL-6 and D-dimer and postprandial reductions in PAI-1, augmentation index and pressure (time effect: P < 0.05). CARB diet was found to reduce HDL₃ by 7.8% and increase small dense HDL (sdHDL) by 8.6% compared with SFA diet (P < 0.05). SFA diet increased large HDL subfractions compared with both CARB and MUFA diets by 4.9% and 6.6% (P < 0.05), respectively.

CONCLUSIONS

Overall, the evidence presented in this study suggests that the replacement of SFA with MUFA or refined carbohydrates may not improve inflammatory and thrombogenic markers in abdominally overweight individuals. Indeed increased refined carbohydrates consumption adversely impacts fasting HDL subfractions. This trial was registered under ClinicalTrials.gov. Identifier no. NCT01665482.

Trans fatty acids and cholesterol levels: An evidence map of the available science

High intakes of industrial trans fatty acids (iTFA) increase circulating low density lipoprotein cholesterol (LDL-C) levels, which has implicated iTFA in coronary heart disease (CHD) risk. Published data on iTFA and LDL-C, however, represent higher intake levels than the U.S. population currently consume. This study used state-of-the-art evidence mapping approaches to characterize the full body of literature on LDL-C and iTFA at low intake levels. A total of 32 independent clinical trials that included at least one intervention or control group with iTFA at ≤3%en were found. Findings indicated that a wide range of oils and interventions were used, limiting the ability to determine an isolated effect of iTFA intake. Few data points were found for iTFA at <3%en, with the majority of low-level exposures actually representing control group interventions containing non-partially hydrogenated (PHO) oils. Further, it appears that few dose-response data points are available to assess the relationship of low levels of iTFA, particularly from PHO exposure, and LDL-C. Therefore, limited evidence is available to determine the effect of iTFA at current consumption levels on CHD risk.

Different consumed oils and metabolic parameters in type 2 diabetes patients in diabetes society of Natanz

AIMS

This study, for the first time, has investigated the effect of highly consumed oils in Iran on type 2 diabetic patient's blood pressure.

MATERIALS AND METHODS

After measuring height, weight and blood pressure and calculating Body Mass Index (BMI) of 200 patients (30-65 years old) with type 2 diabetes (26.7% men, 73.3% women) in diabetes center of Natanz, their consumed oil was obtained by questionnaire, and their blood lipid and glucose were also measured. Data analyzed by SPSS 16 software, one-way ANOVA, independent T test, and Means procedure statistic tests.

RESULTS

In mean procedure test, the highest average of systolic and diastolic blood pressure was in patients consumed solid and semi-solid oils; and the lowest was in patients consumed vegetable liquid oils. However, women consumed solid vegetable oils have lower systolic and mean arterial pressures. In one-way ANOVA test, there was a significant relation between consumed oil and hemoglobin A1C (p=0.049) and diastolic blood pressure (p=0.032).

CONCLUSION

Consumption of solid and semi-solid oils, especially animal fat, cause increasing in blood pressure of diabetic type 2 patients; but consumption of olive oil, and to a lesser extent liquid vegetable oils, related to lesser increasing in their blood pressure.

Is the metabolic syndrome inversely associates with butter, non-hydrogenated- and hydrogenated-vegetable oils consumption: Tehran lipid and glucose study

AIM

The aim of this study was to investigate the association between hydrogenated- (HVOs) and non-hydrogenated vegetable oils (non-HVOs) and butter and the metabolic syndrome (MetS) after 3-years of follow-up in adults.

METHODS

This study was conducted between 2006-2008 and 2009-2011 within the framework of the Tehran Lipid and Glucose Study, on 1582 adults, aged 19-84 years. Intakes of HVOs, non-HVOs and butter were assessed by a validated semi-quantitative food frequency questionnaire. Based on the consumption of food rich in fat including HVOs, non-HVOs and butter, participants were categorized to consumers and non-consumers.

RESULTS

Of 1582 participants during a 3-year follow-up, 15.2% developed MetS. Non-consumption of butter was associated with lower MetS risk compared with its consumption. Among consumers of food rich in fat, intake of HVOs and butter were associated with an increased risk of MetS; ORs in the final multivariate model were 2.70 (95% CI: 1.52-4.78) for HVOs and 2.03 (95% CI: 1.20-3.41) for butter, in the highest, compared to the lowest category of dietary intakes. Intake of non-HVOs was not associated with risk of MetS.

CONCLUSIONS

Consumption of HVOs and butter were positively associated with an increase risk of MetS.

Association between diet-related inflammation, all-cause, all-cancer, and cardiovascular disease mortality, with special focus on prediabetics: findings from NHANES III

INTRODUCTION

Chronic inflammation is associated with increased risk of cancer, cardiovascular disease (CVD), and diabetes. The role of pro-inflammatory diet in the risk of cancer mortality and CVD mortality in prediabetics is unclear. We examined the relationship between diet-associated inflammation, as measured by dietary inflammatory index (DII) score, and mortality, with special focus on prediabetics.

METHODS

This prospective cohort study used data from the Third National Health and Nutrition Examination Survey (NHANES III). We categorized 13,280 eligible participants, ages 20-90 years, according to glycosylated hemoglobin (HgbA1c) level and identified 2681 with prediabetes, defined as a glycosylated hemoglobin percentage of 5.7-6.4. Computation of DII scores and all statistical analyses were conducted in 2015. The DII was computed based on baseline dietary intake assessed using 24-h dietary recalls (1988-1994). Mortality was determined from the National Death Index records through 2006. Over follow-up ranging between 135 and 168 person-months, a total of 3016 deaths were identified, including 676 cancer, 192 lung cancer, 176 digestive-tract cancer, and 1328 CVD deaths. Cox proportional hazard regression was used to estimate hazard ratios.

RESULTS

The prevalence of prediabetes was 20.19 %. After controlling for age, sex, race, HgbA1c, current smoking, physical activity, BMI, and systolic blood pressure, DII scores in tertile III (vs tertile I) was significantly associated with mortality from all causes (HR 1.39, 95 % CI 1.13, 1.72), CVD (HR 1.44, 95 % CI 1.02, 2.04), all cancers (HR 2.02, 95 % CI 1.27, 3.21), and digestive-tract cancer (HR 2.89, 95 % CI 1.08, 7.71). Findings for lung cancer (HR 2.01, 95 % CI 0.93, 4.34) suggested a likely effect. These results were moderately enhanced after additional adjustment for serum low-density lipoprotein and triglyceride and following eliminating deaths during the first year.

CONCLUSIONS

A pro-inflammatory diet, as indicated by higher DII scores, is associated with an increased risk of all-cause, CVD, all-cancer, and digestive-tract cancer mortality among prediabetic subjects.

Hepatocytes respond differently to major dietary trans fatty acid isomers, elaidic acid and trans-vaccenic acid

BACKGROUND

It has been discussed if the adverse health effect associated with the ingestion of trans fatty acids correlates with the food source, as the composition of the isomers varies in different foods. We have investigated the hepatocellular responses to the predominant trans fatty acid isomers in industrially produced partially hydrogenated vegetable oils (elaidic acid) and products of ruminant origin (trans-vaccenic acid).

RESULTS

The responses of HepG2-SF cells exposed to 100 μM fatty acids during 7 days were examined. Elaidic acid decreased the cellular proliferation rate while trans-vaccenic acid had no effect. Analysis of cellular triacylglycerol fractions showed, that both trans fatty acids were metabolized by HepG2-SF cells, although elaidic acid, to a higher degree than trans-vaccenic, accumulated in the triacylglycerol fraction. Proteome analysis revealed that the overlap of differentially regulated proteins only contained four proteins, suggesting that the two trans fatty acid isomers affect the cells in different ways. The data are available via ProteomeXchange with identifier PXD000760.

CONCLUSIONS

Our investigations revealed that the hepatocellular response to the two most abundant dietary positional C18:1 trans fatty acid isomers differ substantially. In addition, the results suggest that trans-vaccenic acid does not affect cholesterol metabolism adversely compared to elaidic acid.

Vaccenic acid and trans fatty acid isomers from partially hydrogenated oil both adversely affect LDL cholesterol: a double-blind, randomized controlled trial

BACKGROUND

Adverse effects of industrially produced trans fatty acids (iTFAs) on the risk of coronary artery disease are well documented in the scientific literature; however, effects of naturally occurring trans fatty acids (TFAs) from ruminant animals (rTFA), such as vaccenic acid (VA) and cis-9,trans-11 conjugated linoleic acid (c9,t11-CLA), are less clear. Although animal and cell studies suggest that VA and c9,t11-CLA may be hypocholesterolemic and antiatherogenic, epidemiologic data comparing rTFAs and iTFAs are inconsistent, and human intervention studies have been limited, underpowered, and not well controlled.

OBJECTIVE

We determined the effects of VA, c9,t11-CLA, and iTFA, in the context of highly controlled diets (24 d each), on lipoprotein risk factors compared with a control diet.

RESULTS

We conducted a double-blind, randomized, crossover feeding trial in 106 healthy adults [mean ± SD age: 47 ± 10.8 y; body mass index (in kg/m(2)): 28.5 ± 4.0; low-density lipoprotein (LDL) cholesterol: 3.24 ± 0.63 mmol/L]. Diets were designed to have stearic acid replaced with the following TFA isomers (percentage of energy): 0.1% mixed isomers of TFA (control), ∼3% VA, ∼3% iTFA, or 1% c9,t11-CLA. Total dietary fat (34% of energy) and other macronutrients were matched. Total cholesterol (TC), LDL cholesterol, triacylglycerol, lipoprotein(a), and apolipoprotein B were higher after VA than after iTFA; high-density lipoprotein (HDL) cholesterol and apolipoprotein AI also were higher after VA. Compared with control, VA and iTFA both increased TC, LDL cholesterol, ratio of TC to HDL cholesterol, and apolipoprotein B (2-6% change; P < 0.05); VA also increased HDL cholesterol, apolipoprotein AI, apolipoprotein B, and lipoprotein(a) (2-6% change; P < 0.05), whereas iTFA did not. c9,t11-CLA lowered triacylglycerol (P ≤ 0.01) and had no effect on other lipoprotein risk factors.

CONCLUSIONS

With respect to risk of cardiovascular disease, these results are consistent with current nutrition labeling guidelines, with the requirement of VA, but not c9,t11-CLA, to be listed under TFA on the Nutrition Facts Panel. This trial was registered at clinicaltrials.gov as NCT00942656.

Is there a linear relationship between the dose of ruminant trans-fatty acids and cardiovascular risk markers in healthy subjects: results from a systematic review and meta-regression of randomised clinical trials

The effects of ruminant (R) trans-fatty acids (TFA) on the risk of CVD are still under debate. It could be argued that the lack of the effect of R-TFA may be the result of the small amount of their intake. Taking into consideration the growing available data from intervention studies, we carried out a systematic review and meta-regression to assess the impact of R-TFA intake levels on changes in the total cholesterol: HDL-cholesterol (TC:HDL-C) ratio. A systematic review of the literature was conducted and thirteen randomised clinical trials were included, yielding a total of twenty-three independent experimental groups of subjects. A univariate random-effects meta-regression approach was used to quantify the relationship between the dose of R-TFA and changes in the TC:HDL-C ratio. To consider several potential modifiers such as subject and dietary characteristics, a multivariate regression analysis was performed. We found no relationship between R-TFA intake levels of up to 4·19 % of daily energy intake (EI) and changes in cardiovascular risk factors such as TC:HDL-C and LDL-cholesterol (LDL-C):HDL-C ratios. In addition, a multivariate regression analysis that included other dietary variables, as well as subject baseline characteristics, confirmed that doses of R-TFA did not significantly influence the changes in the lipid ratio. Our findings showed that doses of R-TFA did not influence the changes in the ratios of plasma TC:HDL-C and LDL-C:HDL-C. These data suggest that TFA from natural sources, at least at the current levels of intake and up to 4·19 % EI, have no adverse effects on these key CVD risk markers in healthy people.

Circulating fatty acids and prostate cancer risk: individual participant meta-analysis of prospective studies

BACKGROUND

Individual studies have suggested that some circulating fatty acids are associated with prostate cancer risk, but have not been large enough to provide precise estimates of associations, particularly by stage and grade of disease.

METHODS

Principal investigators of prospective studies on circulating fatty acids and prostate cancer were invited to collaborate. Investigators provided individual participant data on circulating fatty acids (weight percent) and other characteristics of prostate cancer cases and controls. Prostate cancer risk by study-specific fifths of 14 fatty acids was estimated using multivariable-adjusted conditional logistic regression. All statistical tests were two-sided.

RESULTS

Five thousand and ninety-eight case patients and 6649 control patients from seven studies with an average follow-up of 5.1 (SD = 3.3) years were included. Stearic acid (18:0) was inversely associated with total prostate cancer (odds ratio [OR] Q5 vs Q1 = 0.88, 95% confidence interval [CI] = 0.78 to 1.00, P trend = .043). Prostate cancer risk was, respectively, 14% and 16% greater in the highest fifth of eicosapentaenoic acid (20:5n-3) (OR = 1.14, 95% CI = 1.01 to 1.29, Ptrend = .001) and docosapentaenoic acid (22:5n-3) (OR = 1.16, 95% CI = 1.02 to 1.33, P trend = .003), but in each case there was heterogeneity between studies (P = .022 and P < .001, respectively). There was heterogeneity in the association between docosapentaenoic acid and prostate cancer by grade of disease (P = .006); the association was statistically significant for low-grade disease but not high-grade disease. The remaining 11 fatty acids were not statistically associated with total prostate cancer risk.

CONCLUSION

There was no strong evidence that circulating fatty acids are important predictors of prostate cancer risk. It is not clear whether the modest associations of stearic, eicosapentaenoic, and docosapentaenoic acid are causal.

Unraveling the complex relationship triad between lipids, obesity, and inflammation

Obesity today stands at the intersection between inflammation and metabolic disorders causing an aberration of immune activity, and resulting in increased risk for diabetes, atherosclerosis, fatty liver, and pulmonary inflammation to name a few. Increases in mortality and morbidity in obesity related inflammation have initiated studies to explore different lipid mediated molecular pathways of attempting resolution that uncover newer therapeutic opportunities of anti-inflammatory components. Majorly the thromboxanes, prostaglandins, leukotrienes, lipoxins, and so forth form the group of lipid mediators influencing inflammation. Of special mention are the omega-6 and omega-3 fatty acids that regulate inflammatory mediators of interest in hepatocytes and adipocytes via the cyclooxygenase and lipoxygenase pathways. They also exhibit profound effects on eicosanoid production. The inflammatory cyclooxygenase pathway arising from arachidonic acid is a critical step in the progression of inflammatory responses. New oxygenated products of omega-3 metabolism, namely, resolvins and protectins, behave as endogenous mediators exhibiting powerful anti-inflammatory and immune-regulatory actions via the peroxisome proliferator-activated receptors (PPARs) and G protein coupled receptors (GPCRs). In this review we attempt to discuss the complex pathways and links between obesity and inflammation particularly in relation to different lipid mediators.

Blood levels of saturated and monounsaturated fatty acids as markers of de novo lipogenesis and risk of prostate cancer

De novo lipogenesis has been implicated in prostate carcinogenesis, and blood levels of specific saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) could reflect activity of this pathway. We used gas chromatography to measure blood SFA and MUFA levels in prediagnostic samples from 476 incident prostate cancer cases (1982-1995) in the Physicians' Health Study and an equal number of controls matched on age and smoking status. Five tagging polymorphisms in the fatty acid synthase (FASN) gene (rs1127678, rs6502051, rs4246444, rs12949488, and rs8066956) were related to blood SFA and MUFA levels. Conditional logistic regression was used to estimate the rate ratios, with 95% confidence intervals, of prostate cancer across quintiles of blood fatty acid levels. The polymorphisms rs6502051 and rs4246444 were associated with lower levels of 14:1n-5, 16:1n-7, and 18:1n-9. Blood levels of 16:1n-7 were associated with higher prostate cancer incidence, with rate ratios for men in increasing quintiles of 1.00, 1.40, 1.35, 1.44, and 1.97 (95% confidence interval: 1.27-3.06; Ptrend = 0.003). Furthermore, 16:1n-7 levels were positively related to incidence of high-grade (Gleason score ≥7) tumors (rate ratioQ5-Q1 = 3.92; 95% confidence interval: 1.72-8.94) but not low-grade tumors (rate ratioQ5-Q1 = 1.51; 95% confidence interval: 0.87-2.62) (Pheterogeneity = 0.02). Higher activity of enzymes involved in de novo lipogenesis, as reflected in blood levels of 16:1n-7, could be involved in the development of high-grade prostate cancer.

Obesity, inflammation and diet

Obesity is a state in which there is an over-accumulation of subcutaneous and/or abdominal adipose tissue. This adipose tissue is no longer considered inert and mainly devoted to storing energy; it is emerging as an active tissue in the regulation of physiological and pathological processes, including immunity and inflammation. Adipose tissue produces and releases a variety of adipokines (leptin, adiponectin, resistin, and visfatin), as well as pro- and anti-inflammatory cytokines (tumor necrosis factor-α, interleukin [IL]-4, IL-6, and others). Adipose tissue is also implicated in the development of chronic metabolic diseases such as type 2 diabetes mellitus or cardiovascular disease. Obesity is thus an underlying condition for inflammatory and metabolic diseases. Diet or dietary patterns play critical roles in obesity and other pathophysiological conditions. A healthy diet and some nutrients are generally considered beneficial; however, some dietary nutrients are still considered controversial. In this article, dietary factors that influence inflammation associated with obesity are discussed.

Lipotoxicity: effects of dietary saturated and transfatty acids

The ingestion of excessive amounts of saturated fatty acids (SFAs) and transfatty acids (TFAs) is considered to be a risk factor for cardiovascular diseases, insulin resistance, dyslipidemia, and obesity. The focus of this paper was to elucidate the influence of dietary SFA and TFA intake on the promotion of lipotoxicity to the liver and cardiovascular, endothelial, and gut microbiota systems, as well as on insulin resistance and endoplasmic reticulum stress. The saturated and transfatty acids favor a proinflammatory state leading to insulin resistance. These fatty acids can be involved in several inflammatory pathways, contributing to disease progression in chronic inflammation, autoimmunity, allergy, cancer, atherosclerosis, hypertension, and heart hypertrophy as well as other metabolic and degenerative diseases. As a consequence, lipotoxicity may occur in several target organs by direct effects, represented by inflammation pathways, and through indirect effects, including an important alteration in the gut microbiota associated with endotoxemia. Interactions between these pathways may perpetuate a feedback process that exacerbates an inflammatory state. The importance of lifestyle modification, including an improved diet, is recommended as a strategy for treatment of these diseases.

Averting comfortable lifestyle crises

How have climate change and diet shaped the evolution of human energy metabolism, and responses to vitamin C, fructose and uric acid? Through the last three millennia observant physicians have noted the association of inappropriate diets with increased incidence of obesity, heart disease, diabetes and cancer, and over the past 300 years doctors in the UK observed that overeating increased the incidence of these diseases. Anthropological studies of the Inuit culture in the mid-nineteenth century revealed that humans can survive and thrive in the virtual absence of dietary carbohydrate. In the 1960s, Cahill revealed the flexibility of human metabolism in response to partial and total starvation and demonstrated that type 2 diabetics were better adapted than healthy subjects to conserving protein during fasting. The potential role for brown adipose tissue thermogenesis in temperature maintenance and dietary calorie control was suggested by Rothwell and Stock from their experiments with 'cafeteria fed rats' in the 1980s. Recent advances in gene array studies and PET scanning support a role for this process in humans. The industrialisation of food processing in the twentieth century has led to increases in palatability and digestibility with a parallel loss of quality leading to overconsumption and the current obesity epidemic. The switch from animal to vegetable fats at the beginning of the twentieth century, followed by the rapid increase in sugar and fructose consumption from 1979 is mirrored by a steep increase in obesity in the 1980s, in the UK and USA. Containment of the obesity epidemic is compounded by the addictive properties of sugar which involve the same dopamine receptors in the pleasure centres of the brain as for cocaine, nicotine and alcohol. Of the many other toxic effects of excessive sugar consumption, immunocompromisation, kidney damage, atherosclerosis, oxidative stress and cancer are highlighted. The WHO and guidelines on sugar consumption include: alternative non-sugar sweeteners; toxic side-effects of aspartame. Stevia and xylitol as healthy sugar replacements; the role of food processing in dietary health; and beneficial effects of resistant starch in natural and processed foods. The rise of maize and soya-based vegetable oils have led to omega-6 fat overload and imbalance in the dietary ratio of omega-3 to omega-6 fats. This has led to toxicity studies with industrial trans fats; investigations on health risks associated with stress and comfort eating; and abdominal obesity. Other factors to consider are: diet, cholesterol and oxidative stress, as well as the new approaches to the chronology of eating and the health benefits of intermittent fasting.

Effects of trans fatty acids on glucose homeostasis: a meta-analysis of randomized, placebo-controlled clinical trials

BACKGROUND

Although evidence from cohort studies has suggested that trans fatty acid (TFA) consumption may be associated with insulin resistance and diabetes, randomized placebo-controlled trials (RCTs) have yielded conflicting results.

OBJECTIVE

In a meta-analysis, we combined all available RCTs that examined the role of TFA intake on glucose homeostasis.

DESIGN

A systematic review of PubMed was performed, and a total of 7 RCTs were included in the meta-analysis. Primary outcomes were glucose and insulin concentrations. Secondary outcomes were total, LDL-, and HDL-cholesterol and triglyceride concentrations. The pooled effect size (ES) was calculated through fixed- and random-effects meta-analyses. The potential existence of publication bias was evaluated by using funnel-plot analysis. Metaregression analysis was performed to evaluate for potential dose-response relations between the ES of outcomes and TFA intake.

RESULTS

Increased TFA intake did not result in significant changes in glucose or insulin concentrations. Increased TFA intake led to a significant increase in total and LDL-cholesterol [ES (95% CI): 0.28 (0.04, 0.51) and 0.36 (0.13, 0.60), respectively] and a significant decrease in HDL-cholesterol concentrations [ES (95% CI): -0.25 (-0.48, -0.01)]. Our analysis also showed the absence of publication bias and any dose-response relations between the ES and TFA intake.

CONCLUSIONS

Increased TFA intake does not result in changes in glucose, insulin, or triglyceride concentrations but leads to an increase in total and LDL-cholesterol and a decrease in HDL-cholesterol concentrations. There is no evidence to support a potential benefit of the reduction of dietary TFA intake on glucose homeostasis.

Influence of dairy product and milk fat consumption on cardiovascular disease risk: a review of the evidence

Although evidence has linked the consumption of saturated fat (SF) to increased LDL levels and an increased risk of the development of cardiovascular disease (CVD), recent findings have indicated that the link between CVD and SF may be less straightforward than originally thought. This may be due to the fact that some food sources high in SF contain an array of saturated and unsaturated fatty acids, each of which may differentially affect lipoprotein metabolism, as well as contribute significant amounts of other nutrients, which may alter CVD risk. The purpose of this review is to examine the published research on the relationship between milk fat containing dairy foods and cardiovascular health. The findings indicate that the majority of observational studies have failed to find an association between the intake of dairy products and increased risk of CVD, coronary heart disease, and stroke, regardless of milk fat levels. Results from short-term intervention studies on CVD biomarkers have indicated that a diet higher in SF from whole milk and butter increases LDL cholesterol when substituted for carbohydrates or unsaturated fatty acids; however, they may also increase HDL and therefore might not affect or even lower the total cholesterol:HDL cholesterol ratio. The results from the review also indicate that cheese intake lowers LDL cholesterol compared with butter of equal milk fat content. In addition, the review highlights some significant gaps in the research surrounding the effects of full-fat dairy on CVD outcomes, pointing to the need for long-term intervention studies.

Differential effects of the trans-18:1 isomer profile of partially hydrogenated vegetable oils on cholesterol and lipoprotein metabolism in male F1B hamsters

Trans-fatty acid consumption from partially hydrogenated vegetable oil (PHVO) has been positively associated with multiple cardiovascular disease risk factors and events. This study was designed to examine the effects of trans-fatty acid isomer profile of PHVO on plasma lipids and lipoproteins and hepatic expression of key genes involved in cholesterol and fatty acid metabolism. Thirty-three male F(1)B strain Syrian Golden Hamsters were allocated to 1 of 3 hypercholesterolemic diets containing (5% by weight): 1) tristearin [control fat (CON)]; 2) partially hydrogenated high-oleic acid sunflower oil (PH-SUN); or 3) partially hydrogenated high-linoleic acid safflower oil (PH-SAF). PH-SUN contained more trans-4 to trans-10 18:1 compared with PH-SAF, which contained more trans-11 to trans-16 18:1. The addition of both PHVO to the diet increased plasma total cholesterol concentrations relative to CON, but only PH-SUN increased the plasma ratio of non-HDL:HDL cholesterol compared with CON. PH-SUN increased VLDL (total, large, and medium) and IDL particle concentrations while decreasing total, medium, and small HDL particle concentrations relative to CON. Both PHVO diets increased the hepatic cholesterol ester concentration, whereas the hepatic TG concentration was lower in PH-SUN compared with PH-SAF and CON. Levels of hepatic LDL receptor, HMG-CoA reductase, and sterol response element binding protein 1 mRNA were specifically reduced in the PH-SUN group compared to the CON group. Expression of SREBP1c was upregulated in both PHVO groups compared to CON, whereas only the PH-SAF group had higher levels of the lipogenic enzymes acetyl-CoA carboxylase, fatty acid synthase, and stearoyl-CoA desaturase-1 compared to CON. These results indicate that differences in the trans-fatty acid profile of PHVO can differentially affect lipid and lipoprotein metabolism.

A high intake of trans fatty acids has little effect on markers of inflammation and oxidative stress in humans

Consumption of industrial trans fatty acids (iTFA) increases LDL cholesterol, decreases HDL cholesterol, and is strongly associated with a higher risk of cardiovascular disease (CVD). However, changes in circulating cholesterol cannot explain the entire effect. Therefore, we studied whether iTFA and conjugated linoleic acid (CLA) affect markers of inflammation and oxidative stress. Sixty-one healthy adults consumed each of 3 diets for 3 wk, in random order. Diets were identical except for 7% of energy provided by oleic acid (control diet), iTFA, or CLA. At the end of the 3 wk, we measured plasma inflammatory markers IL-6, C-reactive protein, tumor necrosis factor receptors I and II (TNF-RI and -RII), monocyte chemotactic protein-1 and E-selectin, and urinary 8-iso-PGF(2α), a marker of lipid peroxidation. Consumption of iTFA caused 4% lower TNF-RI concentrations and 6% higher E-selectin concentrations compared with oleic acid (control) and had no significant effect on other inflammatory markers. CLA did not significantly affect inflammatory markers. The urine concentration of 8-iso-PGF(2α) [geometric mean (95% CI)] was greater after the iTFA [0.54 (0.48, 0.60) nmol/mmol creatinine] and the CLA [1.2 (1.1, 1.3) nmol/mmol creatinine] diet periods than after the control period [0.45 (0.41, 0.50) nmol/mmol creatinine; P < 0.05]. In conclusion, high intakes of iTFA and CLA did not substantially affect plasma concentrations of inflammatory markers, but they increased the urine 8-iso-PGF(2α) concentration. However, it is unlikely this plays a major role in the mechanism by which iTFA increase the risk of CVD. However, more research is needed to fully understand the implications of these findings.

Effect of industrially produced trans fat on markers of systemic inflammation: evidence from a randomized trial in women

Consumption of industrially produced trans fatty acids (IP-TFA) has been positively associated with systemic markers of low-grade inflammation and endothelial dysfunction in cross-sectional studies, but results from intervention studies are inconclusive. Therefore, we conducted a 16 week double-blind parallel intervention study with the objective to examine the effect of IP-TFA intake on biomarkers of inflammation, oxidative stress, and endothelial dysfunction. Fifty-two healthy overweight postmenopausal women (49 completers) were randomly assigned to receive either partially hydrogenated soybean oil (15.7 g/day IP-TFA) or control oil without IP-TFA. After 16 weeks, IP-TFA intake increased baseline-adjusted serum tumor necrosis factor (TNF) α by 12% [95% confidence interval (CI): 5-20; P = 0.002] more in the IP-TFA group compared with controls. Plasma soluble TNF receptors 1 and 2 were also increased by IP-TFA [155 pg/ml (CI: 63-247); P < 0.001 and 480 pg/ml (CI: 72-887); P = 0.02, respectively]. Serum C-reactive protein, interleukin (IL) 6 and adiponectin and subcutaneous abdominal adipose tissue mRNA expression of IL6, IL8, TNFα, and adiponectin as well as ceramide content were not affected by IP-TFA, nor was urinary 8-iso-prostaglandin-F(2α). In conclusion, this dietary trial indicates that the mechanisms linking dietary IP-TFA to cardiovascular disease may involve activation of the TNFα system.

Hydrogenated fat intake during pregnancy and lactation caused increase in TRAF-6 and reduced AdipoR1 in white adipose tissue, but not in muscle of 21 days old offspring rats

Background

Although lipids transfer through placenta is very limited, modification in dietary fatty acids can lead to implications in fetal and postnatal development. Trans fatty acid (TFA) intake during gestation and lactation have been reported to promote dyslipidemia and increase in pro- inflammatory adipokines in offspring. The aim of this study was to evaluate whether the alterations on pro-inflammatory cytokines and dyslipidemia observed previously in 21-d-old offspring of rats fed a diet containing hydrogenated vegetable fat during gestation and lactation were related to alterations in TLR-4, TRAF-6 and adipo-R1 receptor in white adipose tissue and muscle. On the first day of gestation, rats were randomly divided into two groups: (C) received a control diet, and (T) received a diet enriched with hydrogenated vegetable fat, rich in trans fatty acids. The diets were maintained throughout gestation and lactation. Each mother was given eight male pups. On the 21st day of life the offspring were killed. Blood, soleus and extensor digital longus (EDL) muscles, and retroperitoneal (RET) white adipose tissue were collected.

Results

21-d-old of T rats had higher serum triacylglycerols, cholesterol, and insulin. The Adipo R1 protein expression was lower in RET and higher in EDL of T group than C. TLR-4 protein content in all studied tissues were similar between groups, the same was verified in TRAF-6 protein expression in soleus and EDL. However, TRAF-6 protein expression in RET was higher in T than C.

Conclusion

These results demonstrated that maternal ingestion of hydrogenated vegetable fat rich in TFAs during gestation and lactation decrease in Adipo R1 protein expression and increase in TRAF-6 protein expression in retroperitoneal adipose tissue, but not in skeletal muscle, which could contributed for hyperinsulinemia and dyslipidemia observed in their 21-d-old offspring.

A mechanism by which dietary trans fats cause atherosclerosis

Dietary trans fats (TFs) have been causally linked to atherosclerosis, but the mechanism by which they cause the disease remains elusive. Suppressed transforming growth factor (TGF)-β responsiveness in aortic endothelium has been shown to play an important role in the pathogenesis of atherosclerosis in animals with hypercholesterolemia. We investigated the effects of a high TF diet on TGF-β responsiveness in aortic endothelium and integration of cholesterol in tissues. Here, we show that normal mice fed a high TF diet for 24 weeks exhibit atherosclerotic lesions and suppressed TGF-β responsiveness in aortic endothelium. The suppressed TGF-β responsiveness is evidenced by markedly reduced expression of TGF-β type I and II receptors and profoundly decreased levels of phosphorylated Smad2, an important TGF-β response indicator, in aortic endothelium. These mice exhibit greatly increased integration of cholesterol into tissue plasma membranes. These results suggest that dietary TFs cause atherosclerosis, at least in part, by suppressing TGF-β responsiveness. This effect is presumably mediated by the increased deposition of cholesterol into cellular plasma membranes in vascular tissue, as in hypercholesterolemia.

Long-term fatty acid stability in human serum cholesteryl ester, triglyceride, and phospholipid fractions

Fatty acid profiles of biological specimens from epidemiological/clinical studies can serve as biomarkers to assess potential relationships between diet and chronic disease risk. However, data are limited regarding fatty acid stability in archived specimens following long-term storage, a variable that could affect result validity. Our objective was to determine the effect of prolonged storage at -80 degrees C on the fatty acid profiles of serum cholesteryl ester (CE), triglyceride (TG), and phospholipid (PL) fractions. This was accomplished by determining the fatty acid profile of frozen, archived, previously unthawed serum samples from 22 subjects who participated in a controlled feeding trial. Initial analysis was performed after trial completion and the repeat analysis after 8-10 years of storage using GC. No significant differences were observed among the majority of fatty acids regardless of lipid fraction. Reliability coefficients were high for the fatty acid classes (saturated fatty acid : 0.70, MUFA : 0.90, PUFA : 0.80). When differences were identified, they were limited to low abundance fatty acids (<or=1.5 mol%). These differences were quantitatively small and likely attributable to technical improvements in GC methodology rather than sample degradation. Thus, our data demonstrate that storage at -80 degrees C up to 10 years does not significantly influence serum CE, TG, or PL fatty acid profiles.

Trans-fatty acids and nonlipid risk factors

Consumption of industrially produced trans-fatty acids (TFA) is associated with substantial risk of coronary heart disease (CHD). The magnitude of this relationship, as well as emerging associations with end points such as diabetes and sudden cardiac death, cannot be fully explained by the well-established adverse effects of TFA on serum lipids. We review the evidence for effects of TFA intake on nonlipid risk factors. Based on evidence from randomized controlled trials, observational studies, animal experiments, and in vitro studies, these include effects on systemic inflammation, endothelial dysfunction, visceral adiposity, insulin resistance, and arrhythmic risk. The types and strength of evidence for each of these nonlipid effects varies, but the overall constellation of findings is qualitatively and quantitatively unique among dietary fats. The multiple adverse effects and implicated pathways are consistent with the observed strong associations of TFA consumption with CHD risk. These nonlipid effects also explain why TFA consumption may adversely impact other non-CHD diseases and end points.

Periodontitis is associated with altered plasma fatty acids and cardiovascular risk markers

BACKGROUND AND AIMS

In periodontitis it has been found that some perturbation exists in lipid biomarkers, such as increased serum total cholesterol and low-density lipoprotein cholesterol. Nevertheless, the relationship between fatty acids and periodontitis has been demonstrated only in a few studies and remains controversial. The aim of this investigation was to explore the effects of periodontitis on a cluster of traditional and novel cardiovascular risk factors such as plasma-lipids profile, types of plasma fatty acids, adhesion molecules and systemic inflammatory markers.

METHODS AND RESULTS

At a university dental school, 56 patients all over 35 years old were enrolled and invited to participate in the study. Total plasma fatty acids, saturated, n-6 polyunsaturated and monounsaturated fatty acids, peroxidability index, soluble VCAM, TNF-alpha, cholesterol, triacylglycerols, and VLDL-c were significantly higher in the periodontitis group compared to the non-periodontitis group.

CONCLUSIONS

This close association found between plasma triacylglycerols, LDL-c, saturated fatty acids, polyunsaturated fatty acids, total amount of fatty acids and coenzyme Q(10) with some periodontal data such as periodontal probing depth, recession of the gingival margin and clinical attachment level (Pearson correlation between 0.3 and 0.6), leads to the conclusion that there is an inter-relationship between periodontitis, plasma fatty acids profile and the increase in metabolic risk factors for cardiovascular diseases.

Trans-11 vaccenic acid reduces hepatic lipogenesis and chylomicron secretion in JCR:LA-cp rats

Trans-11 vaccenic acid (VA) is the predominant trans isomer in ruminant fat and a major precursor to the endogenous synthesis of cis9,trans11-conjugated linoleic acid in humans and animals. We have previously shown that 3-wk VA supplementation has a triglyceride (TG)-lowering effect in a rat model of dyslipidemia, obesity, and metabolic syndrome (JCR:LA-cp rats). The objective of this study was to assess the chronic effect (16 wk) of VA on lipid homeostasis in both the liver and intestine in obese JCR:LA-cp rats. Plasma TG (P < 0.001), total cholesterol (P < 0.001), LDL cholesterol (P < 0.01), and nonesterified fatty acid concentrations, as well as the serum haptoglobin concentration, were all lower in obese rats fed the VA diet compared with obese controls (P < 0.05). In addition, there was a decrease in the postprandial plasma apolipoprotein (apo)B48 area under the curve (P < 0.05) for VA-treated obese rats compared with obese controls. The hepatic TG concentration and the relative abundance of fatty acid synthase and acetyl-CoA carboxylase proteins were all lower (P < 0.05) in the VA-treated group compared with obese controls. Following acute gastrointestinal infusion of a VA-triolein emulsion in obese rats that had been fed the control diet for 3 wk, the TG concentration was reduced by 40% (P < 0.05) and the number of chylomicron (CM) particles (apoB48) in nascent mesenteric lymph was reduced by 30% (P < 0.01) relative to rats infused with a triolein emulsion alone. In conclusion, chronic VA supplementation significantly improved dyslipidemia in both the food-deprived and postprandial state in JCR:LA-cp rats. The appreciable hypolipidemic benefits of VA may be attributed to a reduction in both intestinal CM and hepatic de novo lipogenesis pathways.

Proinflammatory cytokines in CRP baseline regulation

Low-grade inflammation, a minor elevation in the baseline concentration of inflammatory markers such as C-reactive protein (CRP), is nowadays recognized as an important underlying condition in many common diseases. Concentrations of CRP under 10 mg/1 are called low-grade inflammation and values above that are considered as clinically significant inflammatory states. Epidemiological studies have revealed demographic and socioeconomic factors that associate with CRP concentration; these include age, sex, birth weight, ethnicity, socioeconomic status, body mass index (BMI), fiber consumption, alcohol intake, and dietary fatty acids. At the molecular level, production of CRP is induced by proinflammatory cytokines IL-1, IL-6, and IL-17 in the liver, although extra hepatic production most likely contributes to systemic concentrations. The cytokines are produced in response to, for example, steroid hormones, thrombin, C5a, bradykinin, other cytokines, UV-light, neuropeptides and bacterial components, such as lipopolysaccharide. Cytokines exert their biological effects on CRP by signaling through their receptors on hepatic cells and activating different kinases and phosphatases leading to translocation of various transcription factors on CRP gene promoter and production of CRP protein. Genetic polymorphisms in the interleukin genes as well as in CRP gene have been associated with minor elevation in CRP. As minor elevation in CRP is associated with both inflammatory and noninflammatory conditions, it should be noticed that the elevation might just reflect distressed or injured cells homeostasis maintenance in everyday life, rather than inflammation with classical symptoms of redness, swelling, heat, and pain.

[Role of diet on chronic inflammation prevention and control - current evidences]

It is known that low chronic inflammation occurs in several stages of non transmissible chronic diseases, including cardiovascular diseases, obesity and diabetes mellitus, among others. Observational studies and clinical trials indicate that diet plays an important role in the reduction of such diseases. The present manuscript discusses the studies that linked diet macronutrient composition and the levels of inflammatory markers. It has been suggested that the consumption of high glycemic index diets, which have low fiber content and are rich in trans fat cause the activation of the immune system, leading to excessive production of pro-inflammatory mediators and the reduction of the anti-inflammatory ones. Although the results are controversial, healthy dietary intakes with the reduction in fat intake (especially trans and saturated fat) and the increase in fruits, vegetables, and whole grain consumption seem to be associated with the improvement in subclinical inflammatory condition.

Feasibility of recommending certain replacement or alternative fats

Expert groups and public health authorities recommend that trans-fatty acid (TFA) intakes from industrially produced partially hydrogenated vegetable oils (PHVOs) should be less than 1% of total energy intake. The starting point for any regulatory or nonregulatory response to this recommendation is to assess the extent of the problem by determining where in the food supply TFAs are found and the amounts consumed in the population. Unfortunately, this is a particularly difficult task using traditional methods of dietary assessment inasmuch as food composition databases with TFA data are either nonexistent or incomplete in most countries. Current evidence on estimates of intake suggests there is high variability in TFA intakes and their food sources between countries. The ubiquitous presence of PHVOs in the global food supply in bakery products, deep-fried foods, snack foods, confectionery products and table spreads attests to their commercial value and convenience. However, their common use is more the result of historical convenience from an industry infrastructure developed over 50 years based on efficient, cost-effective hydrogenation of vegetable oils rather than any inherent sensory or physical superiority of the hydrogenated fats over purpose-made zero-trans fats and oils. Current global supply of appropriate zero-trans replacement fats high in cis-unsaturated fatty acids is insufficient to meet the demand if all PHVOs in the food supply were replaced. Regulatory action needs to be coordinated with supply to maximize the opportunity for health gains by replacing partially hydrogenated fats with purpose-ready zero-trans vegetable oils low in saturates and high in cis-unsaturates rather than animal fats and tropical oils high in saturated fatty acids.