Trans-fatty acids aggravate anabolic steroid-induced metabolic disturbances and differential gene expression in muscle, pancreas and adipose tissue.

AIMS: Although anabolic steroids (AS) and trans-fatty acids overload exerts systemic toxicity and are independent risk factors for metabolic and cardiovascular disorders, their interaction remains poorly understood. Thus, we investigated the impact of a diet rich in trans-fatty acids (HFD) combined with AS on glycemic control, lipid profile, adipose tissue, skeletal muscle and pancreas microstructure and expression of genes involved in energy metabolism. MAIN METHODS: Forty-eight C57BL/6 mice were randomized into 6 groups treated for 12 weeks with a standard diet (SD) or a diet rich in C18:1 trans-fatty isomers (HFD), alone or combined with 10 or 20 mg/kg testosterone cypionate (AS). KEY FINDINGS: Our results indicated that AS improved glycemic control, upregulated gene expression of Glut-4 and CPT-1 in skeletal muscle, FAS, ACC and UCP-1 in adipose tissue. AS also reduced total and LDL cholesterol in mice fed a SD. When combined with the HFD, AS was unable to induce microstructural adaptations in adipose tissue, pancreatic islets and ß-cells, but potentiated GCK and Glut-2 (pancreas) and Glut-4 and CPT-1 (skeletal muscle) upregulation. HFD plus AS also downregulated FAS and ACC gene expression in adipose tissue. Combined with HFD, AS increased triacylglycerol circulating levels, improved insulin sensitivity and glycemic control in mice. SIGNIFICANCE: Our findings indicated that HFD and AS can interact to modulates glycemic control and lipid profile by a mechanism potentially related with a reprogramming of genes expression in organs such as the pancreas, adipose tissue and skeletal muscle.

Trans-Fatty Acids and Cardiovascular Disease: Urgent Need for Legislation.

Hydrogenated oils containing trans-fatty acids (TFA) are used to produce margarine and various processed foods. TFA affect serum lipid levels, fatty acid metabolism, and endothelial function. High TFA intake is linked to increased all-cause mortality, coronary heart disease mortality, and cardiovascular disease (CVD) incidence. Denmark was the first country to introduce a law that limited TFA content in food; this action led to lower CVD mortality. So far 7 European countries have followed this practice, in a few others the food industry voluntarily reduced TFA use. The issue remains mostly unaddressed in the rest of the world. Legal TFA limits should be commonly established as they are the optimal solution considering both CVD prevention and the associated cost savings in public healthcare.

Trans fatty acids: are its cardiovascular risks fully appreciated?

OBJECTIVE: The goal of this article was to review the causal link between trans fatty acids (TFA) produced from partially hydrogenated vegetable oil (PHVO) and cardiovascular disease (CVD) risk and its likely mechanisms. The potential risk of TFA from ruminant dairy and meats, which are currently the major sources of dietary TFA, is also discussed. METHODS: Evidence was derived from observational studies of large cohorts followed up prospectively; from randomized controlled trials of clinical interventions; and from specific case-control studies that investigated biomarkers in tissues. Searches included PubMed and Medline from 1990 to 2013. RESULTS: Despite TFA from PHVO being associated more strongly with CVD risk than even saturated fats, it may prove difficult to totally eliminate PHVO from all foods. This raises the issue of the lower limit of TFA consumption below which CVD risk is not increased. Limits of <1% of total energy have been suggested. The major mechanism underlying the increased CVD risk from TFA is an increase in LDL-C and Lp(a) lipoproteins and a decrease in HDL-C; increased inflammation and adverse effects on vascular function have also been shown. Both PHVO and ruminant TFA comprise a range of isomers, some specific to each source but including a substantial commonality that supports findings of similar adverse effects at equivalent intakes of TFA. However, the amount of TFA in ruminant fat is relatively small; this limits the CVD risk from eating ruminant products, an inference supported by analysis of prospective cohort studies. CONCLUSIONS: Two key challenges to the health industry arise from this evidence. They must first determine whether a small intake of TFA from PHVO is safe and what constitutes a safe amount. They must also determine whether TFA from ruminant fat in currently consumed amounts represent limited cardiovascular risk that is balanced by the nutritional benefits of dairy products.

Trans fatty acids induce a proinflammatory response in endothelial cells through ROS-dependent nuclear factor-κB activation.

UNLABELLED: It has been shown that increased intake of trans fatty acids (TFAs) is associated with a higher risk of cardiovascular disease. In this study, we have investigated the effects of linoelaidic (LA) and elaidic (EA) acids on the proinflammatory response in endothelial cells, a key step in vascular disease. Human aortic endothelial cells (HAECs) were treated with different concentrations (100 µmol/l in most experiments) of LA or EA for different periods of time. The surface protein and mRNA expression of ICAM-1 and VCAM-1 were determined by flow cytometry and real time RT-PCR, respectively. Adhesion of leukocytes to TFA-treated HAECs was evaluated by an adhesion assay. Activation of nuclear factor-κB (NF-κB) was evaluated by measuring NF-κB p65 phosphorylation using flow cytometry. ROS production was determined by the reduction of fluorescent 2',7'-dichlorofluorescein diacetate (DCFH-DA). LA treatment significantly increased protein and mRNA levels of ICAM-1 and VCAM-1, leukocyte adhesion to HAECs, phosphorylation of NF-κB and ROS generation. Similar effects were achieved for cells incubated with EA. Experiments with HAECs pretreated with pyrrolidine dithiocarbamate, an inhibitor of NF-κB, revealed that both LA and EA-mediated induction of ICAM-1 and VCAM-1 is mainly regulated by NF-κB. The ROS production induced by both of the studied acids was inhibited in the presence of diphenyleneiodonium (DPI), a NADPH oxidase inhibitor, suggesting ROS production through the activation of NADPH oxidase. Furthermore, LA or EA-induced ICAM-1 and VCAM-1 expression, activation of NF-κB and adhesion of leukocytes to HAECs were abolished in the presence of DPI. CONCLUSION: TFAs present in our diet have a direct proinflammatory effect, which promotes leukocyte adhesion to the endothelium through ROS-dependent NF-κB activation.

Fish intake and the risk of incident heart failure: the Women's Health Initiative.

BACKGROUND: Whether fish or the fatty acids they contain are independently associated with risk for incident heart failure (HF) among postmenopausal women is unclear. METHODS AND RESULTS: The baseline Women's Health Initiative Observational Study cohort consisted of 93 676 women ages 50 to 79 years of diverse ethnicity and background, of which 84 493 were eligible for analyses. Intakes of baked/broiled fish, fried fish, and omega-3 fatty acid (eicosapentaenoic acid+docosahexaenoic acid, α-linolenic acid), and trans-fatty acid were determined from the Women's Health Initiative food frequency questionnaire. Baked/broiled fish consumption was divided into 5 frequency categories: <1/mo (referent), 1 to 3/mo, 1 to 2/wk, 3 to 4/wk, ≥5/wk. Fried fish intake was grouped into 3 frequency categories: <1/mo (referent), 1-3/mo, and ≥1/wk. Associations between fish or fatty acid intake and incident HF were determined using Cox models adjusting for HF risk factors and dietary factors. Baked/broiled fish consumption (≥5 servings/wk at baseline) was associated with a hazard ratio of 0.70 (95% confidence interval, 0.51 to 0.95) for incident HF. In contrast, fried fish consumption (≥1 serving/wk at baseline) was associated with a hazard ratio of 1.48 (95% confidence interval, 1.19 to 1.84) for incident HF. No significant associations were found between eicosapentaenoic acid+docosahexaenoic acid, α-linolenic acid, or trans-fatty acid intake and incident HF. CONCLUSIONS: Increased baked/broiled fish intake may lower HF risk, whereas increased fried fish intake may increase HF risk in postmenopausal women.

Trans fat intake in children: risks and recommendations.

Partially hydrogenated oils, also known as trans fat, are found in many baked goods, snack foods, fast foods, margarines, and shortening. Partially hydrogenated oil is vegetable oil that has been modified to be solid at room temperature and lengthens the shelf life of products in which it is used. Consumption of trans fat has been linked to negative changes in lipoproteins, systemic inflammation, coronary heart disease, and diabetes mellitus. Evidence of processes leading to these conditions has also been found in children. Dietary habits and preferences are established in early childhood; therefore, it is important to intervene early with parents to help them make healthier food choices for their families. Educational intervention should reflect successful programs, be based on a theoretical model, and focus on the adverse health effects of consuming trans fat and the importance of choosing a diet that favors unprocessed foods.

[The importance of essential fatty acids and the effect of trans fatty acids in human milk on fetal and neonatal development]. / Importância dos ácidos graxos essenciais e os efeitos dos ácidos graxos trans do leite materno para o desenvolvimento fetal e neonatal.

Breastfeeding has a major impact on public health, since human breast milk is the best food for infants up to six months of age. The lipid fraction in human milk is the main source of energy for the infant and supplies essential nutrients such as fat-soluble vitamins and polyunsaturated fatty acids (PUFA). Essential fatty acids (EFA), specifically linoleic acid (LA, 18:2n-6) and alpha-linolenic acid (ALA, 18:3n-3), are precursors of long-chain polyunsaturated fatty acids (LC-PUFA), including docosahexaenoic (DHA) and arachidonic (ARA) acids. Quality of lipids in secreted milk is precisely related to maternal ingestion. LC-PUFAs protect against allergy and infection and are important for visual and cognitive development in infancy. Industrial food processing has introduced the trans fatty acids (TFA) among the nutrients available to the population. TFA can interfere with the metabolism of essential fatty acids by decreasing LC-PUFA synthesis. It is thus important to raise population awareness on the importance of adequate PUFA consumption and reduced TFA intake during prenatal and postnatal development.

Trans-fatty acid intake and increased risk of advanced prostate cancer: modification by RNASEL R462Q variant.

Previous studies have examined the role of higher trans-fatty acid consumption on prostate cancer risk, but the results remain unclear. Any potential association may be modified by variants in genes involved with immune and inflammatory responses. To investigate this, we undertook a case-control study (N = 1012) of the association between trans-fatty acid intake and advanced prostate cancer, and evaluated whether this effect was modified by a functional polymorphism in the RNASEL gene (R462Q). Among Caucasians (N = 834), we observed that each type of trans-fatty acid and total trans-fatty acid intake showed a statistically significant positive association with prostate cancer, but only weakly increased risk for the isomers of cis-fatty acids. Compared with the lowest quartile of total trans-fatty acid consumption, the higher quartiles gave odds ratios (ORs) equal to 1.58 [95% confidence interval (CI): 1.00, 2.48], 1.95 (95% CI: 1.20, 3.19) and 2.77 (95% CI: 1.60, 4.79) (P-trend = 0.0003); this effect was modified by the RNASEL R462Q polymorphism (P(interaction) = 0.01). Among men with the QQ/RQ genotype, the association between total trans-fatty acid intake and prostate cancer was substantially stronger [ORs of higher quartiles equal to 2.93 (95% CI: 1.62, 5.30), 3.13 (95% CI: 1.64, 5.98) and 4.80 (95% CI: 2.29, 10.08), respectively]. For men with the RR genotype, total trans-fatty acid intake was not associated with disease. This suggests that among Caucasians, positive association between higher trans-fatty acid consumption and prostate cancer may be modified by the functional RNASEL variant R462Q.