Ruminant fat intake improves gut microbiota, serum inflammatory parameter and fatty acid profile in tissues of Wistar rats.

This study tested the hypothesis that naturally and industrially produced trans-fatty acids can exert distinct effects on metabolic parameters and on gut microbiota of rats. Wistar rats were randomized into three groups according to the diet: CONT-control, with 5% soybean oil and normal amount of fat; HVF-20% of hydrogenated vegetable fat (industrial); and RUM-20% of ruminant fat (natural). After 53 days of treatment, serum biochemical markers, fatty acid composition of liver, heart and adipose tissue, histology and hepatic oxidative parameters, as well as gut microbiota composition were evaluated. HVF diet intake reduced triglycerides (≈ 39.39%) and VLDL levels (≈ 39.49%). Trans-fatty acids levels in all tissue were higher in HVF group. However, RUM diet intake elevated amounts of anti-inflammatory cytokine IL-10 (≈ 14.7%) compared to CONT, but not to HVF. Furthermore, RUM intake led to higher concentrations of stearic acid and conjugated linoleic acid in all tissue; this particular diet was associated with a hepatoprotective effect. The microbial gut communities were significantly different among the groups. Our results show that ruminant fat reversed the hepatic steatosis normally caused by high fat diets, which may be related to the remodelling of the gut microbiota and its anti-inflammatory potential.

Trans-palmitoleic acid (trans-9-C16:1, or trans-C16:1 n-7): Nutritional impacts, metabolism, origin, compositional data, analytical methods and chemical synthesis. A review.

Since the early 2010s, dietary trans-palmitoleic acid (trans-9-hexadecenoic acid, trans-9-C16:1 in the Δ-nomenclature, trans-C16:1 n-7 in the Ω-nomenclature, TPA) has been epidemiologically associated with a lower risk of type 2 diabetes in humans. Thanks to these findings, TPA has become a nutrient of interest. However, there is a lot of unresolved crucial questions about this dietary fatty acid. Is TPA a natural trans fatty acid? What kind of foods ensures intakes in TPA? What about its metabolism? How does dietary TPA act to prevent type 2 diabetes? What are the biological mechanisms involved in this physiological effect? Clearly, it is high time to answer all these questions with the very first review specifically dedicated to this intriguing fatty acid. Aiming at getting an overview, we shall try to give an answer to all these questions, relying on appropriate and accurate scientific results. Briefly, this review underlines that TPA is indeed a natural trans fatty acid which is metabolically linked to other well-known natural trans fatty acids. Knowledge on physiological impacts of dietary TPA is limited so far to epidemiological data, awaiting for supplementation studies. In this multidisciplinary review, we also emphasize on methodological topics related to TPA, particularly when it comes to the quantification of TPA in foods and human plasma. As a conclusion, we highlight promising health benefits of dietary TPA; however, there is a strong lack in well-designed studies in both the nutritional and the analytical area.

Fatty acids, epigenetic mechanisms and chronic diseases: a systematic review.

BACKGROUND: Chronic illnesses like obesity, type 2 diabetes (T2D) and cardiovascular diseases, are worldwide major causes of morbidity and mortality. These pathological conditions involve interactions between environmental, genetic, and epigenetic factors. Recent advances in nutriepigenomics are contributing to clarify the role of some nutritional factors, including dietary fatty acids in gene expression regulation. This systematic review assesses currently available information concerning the role of the different fatty acids on epigenetic mechanisms that affect the development of chronic diseases or induce protective effects on metabolic alterations. METHODS: A targeted search was conducted in the PubMed/Medline databases using the keywords "fatty acids and epigenetic". The data were analyzed according to the PRISMA-P guidelines. RESULTS: Consumption fatty acids like n-3 PUFA: EPA and DHA, and MUFA: oleic and palmitoleic acid was associated with an improvement of metabolic alterations. On the other hand, fatty acids that have been associated with the presence or development of obesity, T2D, pro-inflammatory profile, atherosclerosis and IR were n-6 PUFA, saturated fatty acids (stearic and palmitic), and trans fatty acids (elaidic), have been also linked with epigenetic changes. CONCLUSIONS: Fatty acids can regulate gene expression by modifying epigenetic mechanisms and consequently result in positive or negative impacts on metabolic outcomes.

Dietary Fats in Relation to Total and Cause-Specific Mortality in a Prospective Cohort of 521 120 Individuals With 16 Years of Follow-Up.

RATIONALE: Evidence linking saturated fat intake with cardiovascular health is controversial. The associations of unsaturated fats with total and cardiovascular disease (CVD) mortality remain inconsistent, and data about non-CVD mortality are limited. OBJECTIVE: To assess dietary fat intake in relation to total and cause-specific mortality. METHODS AND RESULTS: We analyzed data of 521 120 participants aged 50 to 71 years from the National Institutes of Health-American Association of Retired Persons Diet and Health Study with 16 years of follow-up. Intakes of saturated fatty acids (SFAs), trans-fatty acids, monounsaturated fatty acids (MUFAs), and polyunsaturated fatty acids (PUFAs) were assessed via food frequency questionnaires. Hazard ratios and 95%CIs were estimated using the Cox proportional hazards model. Overall, 129 328 deaths were documented during 7.3 million person-years of follow-up. In the replacement of carbohydrates, multivariable-adjusted hazard ratios of total mortality comparing extreme quintiles were 1.29 (95% CI, 1.25-1.33) for SFAs, 1.03 (1.00-1.05) for trans-fatty acids, 0.98 (0.94-1.02) for MUFAs, 1.09 (1.06-1.13) for animal MUFAs, 0.94 (0.91-0.97) for plant MUFAs, 0.93 (0.91-0.95) for PUFAs, 0.92 (0.90-0.94) for marine omega-3 PUFAs, 1.06 (1.03-1.09) for α-linolenic acid, 0.88 (0.86-0.91) for linoleic acid, and 1.10 (1.08-1.13) for arachidonic acid. CVD mortality was inversely associated with marine omega-3 PUFA intake ( P trend <0.0001), whereas it was positively associated with SFA, trans-fatty acid, and arachidonic acid intake. Isocalorically replacing 5% of the energy from SFAs with plant MUFAs was associated with 15%, 10%, 11%, and 30% lower total mortality, CVD, cancer, and respiratory disease mortality, respectively. Isocaloric replacement of SFA with linoleic acid (2%) was associated with lower total (8%), CVD (6%), cancer (8%), respiratory disease (11%), and diabetes mellitus (9%) mortality. CONCLUSIONS: Intakes of SFAs, trans-fatty acids, animal MUFAs, α-linolenic acid, and arachidonic acid were associated with higher mortality. Dietary intake of marine omega-3 PUFAs and replacing SFAs with plant MUFAs or linoleic acid were associated with lower total, CVD, and certain cause-specific mortality. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov . Unique identifier: NCT00340015.

Effect of industrial trans-fatty acids-enriched diet on gut microbiota of C57BL/6 mice.

PURPOSE: Previous studies have shown that industrially originated trans-fatty acids (iTFAs) are associated with several chronic diseases, but the underlying mechanisms remain unknown. Because gut microbiota play a critical role in human health, diet competent induced gut microbiota dysbiosis may contributing to disease pathogenesis. Therefore, the present study examined the impact of iTFA on gut microbiota, help understanding the underling mechanism of iTFA-associated chronic diseases. METHODS: Forty male 8-week-old mice were divided into 4 groups and randomly assigned to diets containing soybean oil (non-iTFA) or partially hydrogenated soybean oil (iTFA). The intervention groups were: (1) low soybean oil (LS); (2) high soybean oil (HS); (3) low partially hydrogenated oil (LH) and (4) high partially hydrogenated oil (HH). The gut microbiota profiles were determined by 16S rRNA gene sequencing. Physiological parameters and the inflammatory status of the small intestine and other tissues were analyzed. Short-chain fatty acid levels in feces were measured using gas chromatography. RESULTS: The intake of iTFA increased the abundance of well-documented 'harmful' bacteria, such as Proteobacteria and Desulfovibrionaceae (P < 0.05), whereas it decreased relative abundance of 'beneficial' bacteria, such as Bacteroidetes, Lachnospiraceae, Bacteroidales S24-7 (P < 0.05). Surprisingly, the intake of iTFA increased the abundance of the probiotic Lactobacillaceae (P < 0.05). Additionally, the intake of iTFA induced increase of inflammatory parameters, as well as a numerical decrease of fecal butyric acid and valeric acid. CONCLUSIONS: This study, to our knowledge, is the first to demonstrate that the consumption of iTFA resulted in a significant dysbiosis of gut microbiota, which may contribute to the development of chronic diseases associated with iTFA.

Modeled replacement of traditional soybean and canola oil with high-oleic varieties increases monounsaturated fatty acid and reduces both saturated fatty acid and polyunsaturated fatty acid intake in the US adult population.

BACKGROUND: High-oleic (HO) seed oils are being introduced as replacements for trans fatty acid (TFA)-containing fats and oils. Negative health effects associated with TFAs led to their removal from the US Generally Recognized As Safe list. HO oils formulated for use in food production may result in changes in fatty acid intake at population levels. Objectives: The purposes of this study were to 1) identify major food sources of soybean oil (SO) and canola oil (CO), 2) estimate effects of replacing SO and CO with HO varieties on fatty acid intake overall and by age and sex strata, and 3) compare predicted intakes with the Dietary Reference Intakes and Adequate Intakes (AIs) for the essential fatty acids (EFAs) α-linolenic acid (ALA) and linoleic acid (LA). Design: Food and nutrient intakes from NHANES waves 2007-2008, 2009-2010, 2011-2012, and 2013-2014 in 21,029 individuals aged ≥20 y were used to model dietary changes. We estimated the intake of fatty acid with the replacement of HO-SO and HO-CO for commodity SO and CO at 10%, 25%, and 50% and evaluated the potential for meeting the AI at these levels. RESULTS: Each modeling scenario decreased saturated fatty acids (SFAs), although intakes remained greater than recommended for all age and sex groups. Models of all levels increased the intake of total monounsaturated fatty acids (MUFAs), especially oleic acid, and decreased the intake of total polyunsaturated fatty acids (PUFAs), particularly LA and ALA. Replacement of traditional with HO oils at 25-50% places specific adult age and sex groups at risk of not meeting the AI for LA and ALA. Conclusions: The replacement of traditional oils with HO varieties will increase MUFA intake and reduce both SFA and PUFA intakes, including EFAs, and may place specific age and sex groups at risk of inadequate LA and ALA intake.

The Role of Lipids in Human Milk and Infant Formulae.

The quantity and quality of dietary lipids in infant formulae have a significant impact on health outcomes, especially when fat storing and/or absorption are limited (e.g., preterm birth and short bowel disease) or when fat byproducts may help to prevent some pathologies (e.g., atopy). The lipid composition of infant formulae varies according to the different fat sources used, and the potential biological effects are related to the variety of saturated and unsaturated fatty acids. For example, since lipids are the main source of energy when the normal absorptive capacity of the digestive tract is compromised, medium-chain saturated fatty acids might cover this requirement. Instead, ruminant-derived trans fatty acids and metabolites of n-3 long-chain polyunsaturated fatty acids with their anti-inflammatory properties can modulate immune function. Furthermore, dietary fats may influence the nutrient profile of formulae, improving the acceptance of these products and the compliance with dietary schedules.

Dietary fats and cardiovascular health: a summary of the scientific evidence and current debate.

This narrative review summarises the main studies of the role of the different fatty acids in coronary heart disease (CHD) and cardiovascular disease (CVD) risk and the current scientific debate on dietary recommendations. Reduction and substitution of the saturated fatty acids (SFAs) with the polyunsaturated fatty acids (PUFAs) are still the main dietary recommendation to prevent CHD and CVD. In the last few years, however, the strength of the scientific evidence underlying this dietary advice has been questioned. Recent investigations reappraise the previously declared deleterious role of the SFAs and reduce the positive role of PUFAs, mainly the omega-6, whereas the role of monounsaturated fatty acids (MUFAs) remains unclear. In contrast, the negative effects of trans fatty acids (TFAs) seem stronger than previously thought. Finally, criticisms have emerged from a dietary recommendation approach focussed on individual components rather than on wide food items and eating habits.

Serum trans-fatty acids level are positively associated with lower food security among american adults.

OBJECTIVES: In the current study we aimed to assess whether the food security is associated with serum trans-fatty acids (TFAs) and dietary fat. METHODS: Analyses were restricted to participants (from the US National Health and Nutrition Examination Survey) with data available on serum and diet TFAs and food security status from 2009 to 2010. All statistical analyses (analysis of covariance and linear regression) accounted for the survey design and sample weights. RESULTS: We included 3876 participants, overall (48.6%) participants were men, and (51.4%) were women, generally (69.0%) had high food security. Subjects with higher food security had a higher level of education as well (p < 0.001). Age-adjusted, sex-adjusted, race-adjusted, education-adjusted mean of trans 9-octadecenoic acid and trans-9, trans-12-octadecadienoic acid were higher in plasma of participants with lower food security (all p < 0.001), moreover in same model there was a significant positive association between plasma level of trans-11-octadecenoic acid, trans-9-octadecenoic acid and trans-9, trans-12-octadecadienoic acid and score of food security. Further, age, sex, race, education, and energy intake adjusted mean of dietary fatty acids show that total polyunsaturated fatty acids are higher in subjects with higher food security (p = 0.026) while, cholesterol consumption is higher in subjects with lower food security (p = 0.039). CONCLUSIONS: Our findings provide more evidence on the association between food insecurity and the higher level of TFAs in serum and different type of fat in the diet.

Monounsaturated fats from plant and animal sources in relation to risk of coronary heart disease among US men and women.

Background: Monounsaturated fatty acids (MUFAs) improve blood lipid profiles in intervention studies, but prospective evidence with regard to MUFA intake and coronary heart disease (CHD) risk is limited and controversial. Objective: We investigated the associations of cis MUFA intake from plant (MUFA-P) and animal (MUFA-A) sources with CHD risk separately among 63,442 women from the Nurses' Health Study (1990-2012) and 29,942 men from the Health Professionals Follow-Up Study (1990-2012). Design: Intakes of MUFA-Ps and MUFA-As were calculated by using validated food-frequency questionnaires collected every 4 y. Incident nonfatal myocardial infarction and fatal CHD cases (n = 4419) were confirmed by medical record review. Results: During follow-up, MUFA-Ps and MUFA-As contributed 5.8-7.9% and 4.2-5.4% of energy on average, respectively. When MUFA-Ps were modeled to isocalorically replace other macronutrients, HRs (95% CIs) of CHD were 0.83 (0.68, 1.00) for saturated fatty acids (SFAs; 5% of energy), 0.86 (0.76, 0.97) for refined carbohydrates (5% of energy), and 0.80 (0.70, 0.91) for trans fats (2% of energy) (P = 0.05, 0.01, and 0.001, respectively). For MUFA-As, corresponding HRs (95% CIs) for the same isocaloric substitutions were 1.04 (0.79, 1.38) for SFAs, 1.11 (0.91, 1.35) for refined carbohydrates, and 0.88 (0.77, 1.01) for trans fats (P = 0.76, 0.31, and 0.08, respectively). Given the common food sources of SFAs and MUFA-As (Spearman correlation coefficients of 0.81-0.83 between these groups of fatty acids), we further estimated CHD risk when the sum of MUFA-As and SFAs (5% of energy) was replaced by MUFA-Ps, and found that the HR was 0.81 (95% CI: 0.73, 0.90; P < 0.001) for this replacement. Conclusions: The largely different associations of MUFA-Ps and MUFA-As with CHD risk suggest that plant-based foods are the preferable sources of MUFAs for CHD prevention. These findings are observational and warrant confirmation in intervention settings. This study was registered at clinicaltrials.gov as NCT00005152 and NCT00005182.

Modifications in the Consumption of Energy, Sugar, and Saturated Fat among the Mexican Adult Population: Simulation of the Effect When Replacing Processed Foods that Comply with a Front of Package Labeling System.

A Mexican Committee of Nutrition Experts (MCNE) from the National Institute of Public Health (INSP), free from conflict of interest, established food content standards to place the front-of-package (FOP) logo on foods that meet these nutrition criteria. The objectives were to simulate the effect on nutrient intake in the Mexican adult population (20-59 years old) after replacing commonly consumed processed foods with those that meet the FOP nutrition-labeling criteria. Twenty-four hour dietary recalls were collected from the 2012 Mexican National Health and Nutrition Survey (n = 2164 adults). A food database from the INSP was used. Weighted medians and 25-75 inter-quartile ranges (IQR) of energy and nutrient intake were calculated for all subjects by sociodemographic characteristics before and after replacing foods. Significant decreases were observed in energy (-5.4%), saturated fatty acids (-18.9%), trans-fatty acids (-20%), total sugar (-36.8%) and sodium (-10.7%) intake and a significant increase in fiber intake (+15.5%) after replacing foods, using the MCNE nutrition criteria. Replacing commonly consumed processed foods in the diet with foods that meet the FOP nutrition-labeling criteria set by the MCNE can lead to improvements in energy and nutrient intake in the Mexican adult population.

Effect of a trans fatty acid-enriched diet on mitochondrial, inflammatory, and oxidative stress parameters in the cortex and hippocampus of Wistar rats.

PURPOSE: Previously showed that dietary trans fatty acids (TFAs) may cause systemic inflammation and affect the central nervous system (CNS) in Wistar rats by increased levels of cytokines in the cerebrospinal fluid (CSF) and serum (Longhi et al. Eur J Nutr 56(3):1003-1016, 1). Here, we aimed to clarifying the impact of diets with different TFA concentrations on cerebral tissue, focusing on hippocampus and cortex and behavioral performance. METHODS: Wistar rats were fed either a normolipidic or a hyperlipidic diet for 90 days; diets had the same ingredients except for fat compositions, concentrations, and calories. We used lard in the cis fatty acid (CFA) group and PHSO in the TFA group. The intervention groups were as follows: (1) low lard (LL), (2) high lard (HL), (3) low partially hydrogenated soybean oil (LPHSO), and (4) high partially hydrogenated soybean oil (HPHSO). Mitochondrial parameters, tumor necrosis factor alpha (TNF-α), 2'7'-dichlorofluorescein (DCFH) levels in brain tissue, and open field task were analyzed. RESULTS: A worse brain tissue response was associated with oxidative stress in cortex and hippocampus as well as impaired inflammatory and mitochondrial parameters at both PHSO concentrations and there were alterations in the behavioral performance. In many analyses, there were no significant differences between the LPHSO and HPHSO diets. CONCLUSIONS: Partially hydrogenated soybean oil impaired cortical mitochondrial parameters and altered inflammatory and oxidative stress responses, and the hyperlipidic treatment caused locomotor and exploratory effects, but no differences on weight gain in all treatments. These findings suggest that quality is more important than the quantity of fat consumed in terms of CFA and TFA diets.

Adult Nutrient Intakes from Current National Dietary Surveys of European Populations.

The World Health Organization (WHO) encourages countries to undertake national dietary survey (NDS) but implementation and reporting is inconsistent. This paper provides an up-to-date review of adult macro and micronutrient intakes in European populations as reported by NDS. It uses WHO Recommended Nutrient Intakes (RNIs) to assess intake adequacy and highlight areas of concern. NDS information was gathered primarily by internet searches and contacting survey authors and nutrition experts. Survey characteristics and adult intakes by gender/age group were extracted for selected nutrients and weighted means calculated by region. Of the 53 WHO Europe countries, over a third (n = 19), mainly Central & Eastern European countries (CEEC), had no identifiable NDS. Energy and nutrient intakes were extracted for 21 (40%) countries but differences in age group, methodology, under-reporting and nutrient composition databases hindered inter-country comparisons. No country met more than 39% WHO RNIs in all age/gender groups; macronutrient RNI achievement was poorer than micronutrient. Overall RNI attainment was slightly worse in CEEC and lower in women and female elderly. Only 40% countries provided adult energy and nutrient intakes. The main gaps lie in CEEC, where unknown nutrient deficiencies may occur. WHO RNI attainment was universally poor for macronutrients, especially for women, the female elderly and CEEC. All countries could be encouraged to report a uniform nutrient set and sub-analyses of nationally representative nutrient intakes.

Abdominal obesity and type 2 diabetes in Asian Indians: dietary strategies including edible oils, cooking practices and sugar intake.

Obesity and type 2 diabetes are increasing in rural and urban regions of South Asia including India. Pattern of fat deposition in abdomen, ectopic fat deposition (liver, pancreas) and also low lean mass are contributory to early-onset insulin resistance, dysmetabolic state and diabetes in Asian Indians. These metabolic perturbations are further exacerbated by changing lifestyle, diet urbanization, and mechanization. Important dietary imbalances include increasing use of oils containing high amount of trans fatty acids and saturated fats (partially hydrogenated vegetable oil, palmolein oil) use of deep frying method and reheating of oils for cooking, high intake of saturated fats, sugar and refined carbohydrates, low intake of protein, fiber and increasing intake of processed foods. Although dietary intervention trials are few; the data show that improving quality of carbohydrates (more complex carbohydrates), improving fat quality (more monounsaturated fatty acids and omega 3 polyunsaturated fatty acids) and increasing protein intake could improve blood glucose, serum insulin, lipids, inflammatory markers and hepatic fat, but more studies are needed. Finally, regulatory framework must be tightened to impose taxes on sugar-sweetened beverages, oils such as palmolein, and dietary fats and limit trans fats.

Organic food consumption during pregnancy is associated with different consumer profiles, food patterns and intake: the KOALA Birth Cohort Study.

OBJECTIVE: To find out how the consumption of organic food during pregnancy is associated with consumer characteristics, dietary patterns and macro- and micronutrient intakes. DESIGN: Cross-sectional description of consumer characteristics, dietary patterns and macro- and micronutrient intakes associated with consumption of organic food during pregnancy. SETTING: Healthy, pregnant women recruited to a prospective cohort study at midwives' practices in the southern part of the Netherlands; to enrich the study with participants adhering to alternative lifestyles, pregnant women were recruited through various specific channels. SUBJECTS: Participants who filled in questionnaires on food frequency in gestational week 34 (n 2786). Participant groups were defined based on the share of organic products within various food types. RESULTS: Consumers of organic food more often adhere to specific lifestyle rules, such as vegetarianism or anthroposophy, than do participants who consume conventional food only (reference group). Consumption of organic food is associated with food patterns comprising more products of vegetable origin (soya/vegetarian products, vegetables, cereal products, bread, fruits, and legumes) and fewer animal products (milk and meat), sugar and potatoes than consumed in conventional diets. These differences translate into distinct intakes of macro- and micronutrients, including higher retinol, carotene, tocopherol and folate intakes, lower intakes of vitamin D and B12 and specific types of trans-fatty acids in the organic groups. These differences are seen even in groups with low consumption of organic food. CONCLUSIONS: Various consumer characteristics, specific dietary patterns and types of food intake are associated with the consumption of organic food during pregnancy.

Trans-Fatty Acid-Stimulated Mammary Gland Growth in Ovariectomized Mice is Fatty Acid Type and Isomer Specific.

We previously reported that the trans-18:2 fatty acid trans-10, cis-12 conjugated linoleic acid (t10,c12-CLA) stimulates mammary gland development independent of estrogen and its receptor. Given the negative consequences of dietary trans-fatty acids on various aspects of human health, we sought to establish whether other trans-fatty acids could similarly induce ovary-independent mammary gland growth in mice. Prepubertal BALB/cJ mice were ovariectomized at 21 days of age then were fed diets enriched with cis-9, trans-11 CLA (c9,t11-CLA), or mixtures of trans-18:1 fatty acids supplied by partially hydrogenated sunflower, safflower, or linseed oil. The resultant mammary phenotype was evaluated 3 weeks later and compared to the growth response elicited by t10,c12-CLA, or the defined control diet. Whereas partially hydrogenated safflower oil increased mammary gland weight, none of the partially hydrogenated vegetable oils promoted mammary ductal growth. Similarly, the c9,t11-CLA supplemented diet was without effect on mammary development. Taken together, our data emphasize a unique effect of t10,c12-CLA in stimulating estrogen-independent mammary gland growth manifest as increased mammary ductal area and elongation that was not recapitulated by c9,t11-CLA or the partially hydrogenated vegetable oil diets.

Effect of a trans fatty acid-enriched diet on biochemical and inflammatory parameters in Wistar rats.

PURPOSE: Recent data regarding trans fatty acids (TFAs) have implicated these lipids as particularly deleterious to human health, causing systemic inflammation, endothelial dysfunction and possibly inflammation in the central nervous system (CNS). We aimed to clarify the impact of partially hydrogenated soybean oil (PHSO) with different TFA concentrations on cerebrospinal fluid (CSF), serum and hepatic parameters in adult Wistar rats. METHODS: Wistar rats (n = 15/group) were fed either a normolipidic diet or a hyperlipidic diet for 90 days. The normolipidic and hyperlipidic diets had the same ingredients except for fat compositions, concentrations and calories. We used lard in the cis fatty acid group and PHSO in the trans fatty acid group. The intervention groups were as follows: (1) low lard (LL), (2) high lard (HL), (3) low partially hydrogenated soybean oil (LPHSO) and (4) high partially hydrogenated soybean oil (HPHSO). Body weight, lipid profiles and the inflammatory responses in the CSF, serum and liver tissue were analyzed. RESULTS: Surprisingly, with the PHSO diet we observed a worse metabolic response that was associated with oxidative stress in hepatic tissue as well as impaired serum and CSF fluid parameters at both PHSO concentrations. In many analyses, there were no significant differences between the LPHSO and HPHSO diets. CONCLUSIONS: Dietary supplementation with PHSO impaired inflammatory parameters in CSF and blood, induced insulin resistance, altered lipid profiles and caused hepatic damage. Overall, these findings suggest that fat composition is more important than the quantity of fat consumed in terms of cis and trans fatty acid diets.

PPARα protects against trans-fatty-acid-containing diet-induced steatohepatitis.

Consumption of trans-fatty acids (TFA), unsaturated fatty acids (FA) containing trans double bonds, is a risk factor for metabolic syndrome and steatohepatitis. Peroxisome proliferator-activated receptor α (PPARα) is a master regulator of hepatic lipid homeostasis. To examine the contribution of PPARα to changes in liver phenotypes induced by TFA, two diets were used: a purified control diet and an isocaloric diet in which most of the soybean oil, a major source of FA in the diet, was replaced with TFA-rich shortening. The diets were fed to wild-type and Ppara-null mice for 2 months. Ppara-null mice fed a TFA-containing diet showed more severe hepatic steatosis and liver damage compared with similarly treated wild-type mice, as revealed by increased hepatic triglyceride (TG) contents and serum alanine aminotransferase activities. While the TFA-rich diet increased the hepatic expression of enzymes involved in de novo FA synthesis and decreased TG-hydrolyzing enzymes in both genotypes, the expression of FA-catabolizing enzymes was decreased in Ppara-null mice, resulting in more severe hepatosteatosis. Additionally, the expression levels of key contributors to inflammation, such as osteopontin, were increased, and nuclear factor-kappa B was activated in TFA-containing diet-fed Ppara-null mice. Enhanced inflammatory signaling in these mice was presumably mediated by toll-like receptor 2, with no accompanying inflammasome activation. Collectively, these results suggest a protective role for PPARα in the pathological changes in the liver following TFA consumption. PPARα might prevent TFA-containing diet-induced steatohepatitis.

N-3 fatty acids reduced trans fatty acids retention and increased docosahexaenoic acid levels in the brain.

INTRODUCTION: The levels of docosahexaenoic acid (DHA, 22:6n-3) and arachidonic acid (AA, 20:4n-6) are critical for the normal structure and function of the brain. Trans fatty acids (TFA) and the source of the dietary fatty acids (FA) interfere with long-chain polyunsaturated fatty acids (LC-PUFA) biosynthesis. OBJECTIVES: The aim of this study was to investigate the effect of TFA supplementation in diets containing different proportions of n-9, n-6, and n-3 FA on the brain FA profile, including the retention of TFA, LC-PUFA levels, and n-6/n-3 PUFA ratios. These parameters were also investigated in the liver, considering that LC-PUFA are mainly bioconverted from their dietary precursors in this tissue and transported by serum to the brain. Also, stearoyl-CoA desaturase-1 (SCD1) and sterol regulatory element-binding protein-1c (SREBP-1c) gene expressions were evaluated. METHODS: Male CF1 mice were fed (16 weeks) diets containing different oils (olive, corn, and rapeseed) with distinct proportions of n-9, n-6, and n-3 FA (55.2/17.2/0.7, 32.0/51.3/0.9, and 61.1/18.4/8.6), respectively, substituted or not with 0.75% of TFA. FA composition of the brain, liver, and serum was assessed by gas chromatography. RESULTS: TFA were incorporated into, and therefore retained in the brain, liver, and serum. However, the magnitude of retention was dependent on the tissue and type of isomer. In the brain, total TFA retention was lower than 1% in all diets. DISCUSSION: Dietary n-3 PUFA decreased TFA retention and increased DHA accretion in the brain. The results underscore the importance of the type of dietary FA on the retention of TFA in the brain and also on the changes of the FA profile.

Oxidative stress in relation to diet and physical activity among premenopausal women.

Higher levels of oxidative stress, as measured by F2-isoprostanes, have been associated with chronic diseases such as CVD and some cancers. Improvements in diet and physical activity may help reduce oxidative stress; however, previous studies regarding associations between lifestyle factors and F2-isoprostane concentrations have been inconsistent. The aim of this cross-sectional study was to investigate whether physical activity and intakes of fruits/vegetables, antioxidant nutrients, dietary fat subgroups and alcohol are associated with concentrations of F2-isoprostane and the major F2-isoprostane metabolite. Urinary F2-isoprostane and its metabolite were measured in urine samples collected at enrolment from 912 premenopausal women (aged 35-54 years) participating in the Sister Study. Physical activity, alcohol consumption and dietary intakes were self-reported via questionnaires. With adjustment for potential confounders, the geometric means of F2-isoprostane and its metabolite were calculated according to quartiles of dietary intakes, alcohol consumption and physical activity, and linear regression models were used to evaluate trends. Significant inverse associations were found between F2-isoprostane and/or its metabolite and physical activity, vegetables, fruits, vitamin C, α-carotene, vitamin E, ß-carotene, vitamin A, Se, lutein+zeaxanthin and long-chain n-3 fatty acids. Although trans fats were positively associated with both F2-isoprostane and its metabolite, other dietary fat subgroups including SFA, n-6 fatty acids, n-3 fatty acids, MUFA, PUFA, short-chain n-3 fatty acids, long-chain n-3 fatty acids and total fat were not associated with either F2-isoprostane or its metabolite. Our findings suggest that lower intake of antioxidant nutrients and higher intake of trans fats may be associated with greater oxidative stress among premenopausal women.