Beneficial effects of omega-3 fatty acids on the consequences of a fructose diet are not mediated by PPAR delta or PGC1 alpha

Purpose

To study, in high-fructose-fed rats, the effect of a dietary enrichment in omega-3 polyunsaturated fatty acids (n-3 PUFA) on the expression of genes involved in lipid metabolism and cardiovascular function.

Methods

Twenty-eight male “Wistar Han” rats received for 8 weeks, either a standard chow food or an isocaloric 67 % fructose diet enriched or not in alpha-linolenic acid (ALA) or in docosahexaenoic (DHA) and eicosapentaenoic acids (EPA) mix (DHA/EPA). After sacrifice, blood was withdrawn for biochemical analyses; heart, periepididymal adipose tissue and liver were collected and analyzed for the expression of 22 genes by real-time PCR.

Results

Fructose intake resulted in an increase in liver weight and triglyceride content, plasma triglyceride and cholesterol concentrations, although no difference in glucose and insulin. In the liver, lipogenesis was promoted as illustrated by an increase in stearoyl-CoA desaturase and fatty acid synthase (Fasn) together with a decrease in PPAR gamma, delta and PPAR gamma coactivator 1 alpha (PGC1 alpha) expression. In the heart, Fasn and PPAR delta expression were increased. The addition of ALA or DHA/EPA into the diet resulted in a protection against fructose effects except for the decreased expression of PPARs in the liver that was not counterbalanced by n-3 PUFA suggesting that n-3 PUFA and fructose act independently on the expression of PPARs and PGC1 alpha.

Conclusions

In liver, but not in heart, the fructose-enriched diet induces an early tissue-specific reduction in PPAR gamma and delta expression, which is insensitive to n-3 PUFA intake and dissociated from lipogenesis.     

Omega-3 and omega-6 fatty acid intakes and endometrial cancer risk in a population-based case–control study

Purpose

Animal and laboratory studies suggest that long-chain omega-3 (n-3) fatty acids, a type of polyunsaturated fat found in fatty fish, may protect against carcinogenesis, but human studies on dietary intake of polyunsaturated fats and fish with endometrial cancer risk show mixed results.

Methods

We evaluated the associations between endometrial cancer risk and intake of fatty acids and fish in a population-based sample of 556 incident cancer cases and 533 age-matched controls using multivariate unconditional logistic regression methods.

Results

Although total n-3 fatty acid intake was not associated with endometrial cancer risk, higher intakes of eicosapentaenoic (EPA 20:5) and docosahexaenoic (DHA 22:6) fatty acids were significantly associated with lower risks (OR = 0.57, 95 % CI: 0.39–0.84; OR = 0.64, 95 % CI: 0.44–0.94; respectively) comparing extreme quartiles. The ratio of n-3:n-6 fatty acids was inversely associated with risk only on a continuous scale (OR = 0.84, 95 % CI: 0.71–0.99), while total fish intake was not associated with risk. Fish oil supplement use was significantly associated with reduced risk of endometrial cancer: OR = 0.63 (95 % CI: 0.45–0.88).

Conclusions

Our results suggest that dietary intake of the long-chain polyunsaturated fatty acids EPA and DHA in foods and supplements may have protective associations against the development of endometrial cancer.     

A short-term n-3 DPA supplementation study in humans

Purpose

Despite the detailed knowledge of the absorption and incorporation of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) into plasma lipids and red blood cells (RBC) in humans, very little is known about docosapentaenoic acid (DPA, 22:5 n-3). The aim of this study was to investigate the uptake and incorporation of pure DPA and EPA into human plasma and RBC lipids.

Methods

Ten female participants received 8 g of pure DPA or pure EPA in randomized crossover double-blinded manner over a 7-day period. The placebo treatment was olive oil. Blood samples were collected at days zero, four and seven, following which the plasma and RBC were separated and used for the analysis of fatty acids.

Results

Supplementation with DPA significantly increased the proportions of DPA in the plasma phospholipids (PL) (by twofold) and triacylglycerol (TAG) fractions (by 2.3-fold, day 4). DPA supplementation also significantly increased the proportions of EPA in TAG (by 3.1-fold, day 4) and cholesterol ester (CE) fractions (by 2.0-fold, day 7) and of DHA in TAG fraction (by 3.1-fold, day 4). DPA proportions in RBC PL did not change following supplementation. Supplementation with EPA significantly increased the proportion of EPA in the plasma CE and PL fractions, (both by 2.7-fold, day 4 and day 7) and in the RBC PL (by 1.9-fold, day 4 and day 7). EPA supplementation did not alter the proportions of DPA or DHA in any lipid fraction. These results showed that within day 4 of supplementation, DPA and EPA demonstrated different and specific incorporation patterns.

Conclusion

The results of this short-term study suggest that DPA may act as a reservoir of the major long-chain n-3 fatty acids (LC n-3 PUFA) in humans.     

Milk phospholipid and plant sterol-dependent modulation of plasma lipids in healthy volunteers

Purpose

Hypolipidemic and/or hypocholesterolemic effects are presumed for dietary milk phospholipid (PL) as well as plant sterol (PSt) supplementation. The aim was to induce changes in plasma lipid profile by giving different doses of milk PL and a combination of milk PL with PSt to healthy volunteers.

Methods

In an open-label intervention study, 14 women received dairy products enriched with moderate (3 g PL/day) or high (6 g PL/day) dose of milk PL or a high dose of milk PL combined with PSt (6 g PL/day + 2 g PSt/day) during 3 periods each lasting 10 days.

Results

Total cholesterol concentration and HDL cholesterol concentration were reduced following supplementation with 3 g PL/day. No significant change in LDL cholesterol concentration was found compared with baseline. High PL dose resulted in an increase of LDL cholesterol and unchanged HDL cholesterol compared with moderate PL dose. The LDL/HDL ratio and triglyceride concentration remained constant within the study. Except for increased phosphatidyl ethanolamine concentrations, plasma PL concentrations were not altered during exclusive PL supplementations. A combined high-dose PL and PSt supplementation led to decreased plasma LDL cholesterol concentration, decreased PL excretion, increased plasma sphingomyelin/phosphatidyl choline ratio, and significant changes in plasma fatty acid distribution compared with exclusive high-dose PL supplementation.

Conclusion

Milk PL supplementations influence plasma cholesterol concentrations, but without changes of LDL/HDL ratio. A combined high-dose milk PL and PSt supplementation decreases plasma LDL cholesterol concentration, but it probably enforces absorption of fatty acids or fatty acid-containing hydrolysis products that originated during lipid digestion.     

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

Background

Dietary long-chain polyunsaturated fatty acids (LC-PUFA) are of crucial importance for the development of neural tissues. The aim of this study was to evaluate the impact of a dietary supplementation in n-3 fatty acids in female rats during gestation and lactation on fatty acid pattern in brain glial cells phosphatidylethanolamine (PE) and phosphatidylserine (PS) in the neonates.

Methods

Sprague-Dawley rats were fed during the whole gestation and lactation period with a diet containing either docosahexaenoic acid (DHA, 0.55%) and eicosapentaenoic acid (EPA, 0.75% of total fatty acids) or α-linolenic acid (ALA, 2.90%). At two weeks of age, gastric content and brain glial cell PE and PS of rat neonates were analyzed for their fatty acid and dimethylacetal (DMA) profile. Data were analyzed by bivariate and multivariate statistics.

Results

In the neonates from the group fed with n-3 LC-PUFA, the DHA level in gastric content (+65%, P < 0.0001) and brain glial cell PE (+18%, P = 0.0001) and PS (+15%, P = 0.0009) were significantly increased compared to the ALA group. The filtered correlation analysis (P < 0.05) underlined that levels of dihomo-γ-linolenic acid (DGLA), DHA and n-3 docosapentaenoic acid (DPA) were negatively correlated with arachidonic acid (ARA) and n-6 DPA in PE of brain glial cells. No significant correlation between n-3 and n-6 LC-PUFA were found in the PS dataset. DMA level in PE was negatively correlated with n-6 DPA. DMA were found to occur in brain glial cell PS fraction; in this class DMA level was correlated negatively with DHA and positively with ARA.

Conclusion

The present study confirms that early supplementation of maternal diet with n-3 fatty acids supplied as LC-PUFA is more efficient in increasing n-3 in brain glial cell PE and PS in the neonate than ALA. Negative correlation between n-6 DPA, a conventional marker of DHA deficiency, and DMA in PE suggests n-6 DPA that potentially be considered as a marker of tissue ethanolamine plasmalogen status. The combination of multivariate and bivariate statistics allowed to underline that the accretion pattern of n-3 LC-PUFA in PE and PS differ.     

Increased linoleic acid/α-linolenic acid ratio in Swedish cord blood samples collected between 1985 and 2005

Background

Cord serum (CS) phospholipid fatty acid composition is associated with maternal diet during foetal life, and maternal intake of linoleic acid (LA, C18:2ω-6) and α-linolenic acid (LNA, C18:3 ω-3) has been shown to influence the LA and LNA levels in CS. A possible connection between the increased incidence of atopic diseases and increased intake of LA and decreased intake of LNA in the Western world has been proposed.

Aim

The aim of this study was to explore phospholipid fatty acid proportions and total IgE levels in CS from Swedish children, collected from 1985 to 2005, a period with increasing frequency of allergic diseases in Sweden, and reveal possible changes over time.

Method

Phospholipid fatty acids and total IgE antibodies were analysed with gas chromatography and UniCAP^® technology, respectively, in 300 CS samples.

Results

The proportions of LA and LNA decreased significantly from 1985 to 2005 (p < 0.001 for both). However, the LA/LNA ratio did increase (p < 0.001), revealing a relatively larger decrease in LNA than in LA. No correlations were found between ω-6 and ω-3 fatty acids and total IgE antibodies in CS from newborn children.

Conclusions

The LA/LNA ratio increased (p < 0.001) in cord serum samples collected between 1985 and 2005, and no correlations between fatty acids and total IgE were found.     

Homocysteine,antioxidant micronutrients and late onset dementia

Purpose

To distinguish between contributions to dementia made by homocysteine, folate, B12 and antioxidant micronutrients.

Methods

This is a follow-up study of a sample reported in 2002. Homocysteine was measured at baseline in 201 individuals born in 1921 and without dementia at age 77 years and followed up to age 88 years. Baseline macro- and micronutrient status was estimated from BMI, the MONICA food frequency questionnaire, plasma folate, B12 and, in a subgroup (N = 173), plasma antioxidant micronutrients. Time to dementia onset during follow-up was compared between participants grouped by homocysteine concentration using Cox regression. Model 1 adjusted for age, sex, childhood IQ, education, socioeconomic deprivation, presence of heart disease, hypertension, plasma folate and B12. In model 2 plasma, antioxidants were added to these covariables.

Results

During a mean follow-up of about 5 years, there were 39 incident dementia cases among 201 participants. In model 1, being in the highest homocysteine group (>14 μmol/L) was associated with a 234 % increased risk (HR 3.34, 95 % CI 1.16–9.57) of any dementia. After inclusion of plasma antioxidants in model 2, there were 32 incident dementia cases from a subsample (N = 173). Homocysteine >14 μmol was associated with a 272 % increased dementia risk (HR = 3.72, 95 % CI 1.06–13.08).

Conclusions

High homocysteine increases the risk of dementia. The association between tHcy and dementia is independent of plasma folate, B12 and antioxidant micronutrient status.     

Circulating linoleic acid and alpha-linolenic acid and glucose metabolism: the Hoorn Study

Purpose

Data on the relation between linoleic acid (LA) and alpha-linolenic acid (ALA) and type 2 diabetes mellitus (T2DM) risk are scarce and inconsistent. The aim of this study was to investigate the association of serum LA and ALA with fasting and 2 h post-load plasma glucose and glycated hemoglobin (HbA1c).

Method

This study included 667 participants from third examination (2000) of the population-based Hoorn study in which individuals with glucose intolerance were overrepresented. Fatty acid profiles in serum total lipids were measured at baseline, in 2000. Diabetes risk markers were measured at baseline and follow-up in 2008. Linear regression models were used in cross-sectional and prospective analyses.

Results

In cross-sectional analyses (n = 667), serum LA was inversely associated with plasma glucose, both in fasting conditions (B = ?0.024 [?0.045, ?0.002]) and 2 h after glucose tolerance test (B = ?0.099 [?0.158, ?0.039]), but not with HbA1c (B = 0.000 [?0.014, 0.013]), after adjustment for relevant factors. In prospective analyses (n = 257), serum LA was not associated with fasting (B = 0.003 [?0.019, 0.025]) or post-load glucose (B = ?0.026 [?0.100, 0.049]). Furthermore, no significant associations were found between serum ALA and glucose metabolism in cross-sectional or prospective analyses.

Conclusions

In this study, serum LA was inversely associated with fasting and post-load glucose in cross-sectional, but not in prospective analyses. Further studies are needed to elucidate the exact role of serum LA and ALA levels and dietary polyunsaturated fatty acids in glucose metabolism.

     

Adipose tissue fatty acid composition and colon cancer: a case–control study

Purpose

An increased dietary intake of fat, particularly polyunsaturated fatty acids (PUFAs), has been related to an increased risk of breast, prostate and colon cancers. Patients with and without colon cancer were tested for differences in their fatty stores composition.

Methods

The fatty acid levels were determined by gas–liquid chromatography in adipose tissue samples, subcutaneous and visceral, obtained intra-operatively from 52 colon cancer and 50 nonneoplastic abdominal disease patients. Statistical analysis was performed using one-way ANOVA, SNK test and Dunnet test. Differences in the composition of saturated, monounsaturated and polyunsaturated fatty acids, in visceral and in subcutaneous samples of colon cancer and nonneoplastic patients, were assessed.

Results

The sum of saturated and monounsaturated fatty acids, respectively, in visceral and in subcutaneous samples, was higher in neoplastic patients (p < 0.001). The sum of some n-6 polyunsaturated fatty acids (PUFAs), the dietary precursor linoleic acid (LA-18:2n-6), and their metabolites, gammalinolenic acid (GLA-18:3n-6) + dihomogammalinolenic acid (DGLA-20:3n-6) + arachidonic acid (AA-22:4n-6), was higher in subcutaneous fat of controls (p < 0.05). The samples from these patients had a fatty acid composition, both subcutaneous and visceral, with a higher content of alphalinolenic acid (ALA-18:3n-3) and stearidonic acid (SDA-18:4n-3) compared to neoplastic patients (p < 0.001). These had subcutaneous and visceral fat stores statistically higher in GLA, DGLA and AA (p < 0.001). Colon cancer patients had subcutaneous adipose stores higher in ALA and LA than visceral sites (p < 0.001).

Conclusions

Fatty acids may be involved in colon carcinogenesis and there is a depot-specific impact on this process by visceral fat.     

Distribution of procyanidins and their metabolites in rat plasma and tissues in relation to ingestion of procyanidin-enriched or procyanidin-rich cocoa creams

Background

Procyanidins are extensively metabolized via phase-II and microbial enzymes. However, their distribution in the body is not well characterized.

Aim

This study investigates the distribution of procyanidins (monomers and dimers) and their phase-II metabolites in plasma and tissues (thymus, heart, liver, testicle, lung, kidney, spleen and brain).

Methods

Wistar rats were fed with 1 g of cocoa cream (CC), 50 mg of procyanidin hazelnut skin extract (PE) and 50 mg PE in 1 g CC (PECC). The rats were killed at 0, 1, 1.5, 2, 3, 4 and 18 h after gavage, and the plasma and tissues were analyzed by UPLC–MS/MS.

Results

Epicatechin–glucuronide was the main metabolite in the plasma after the CC intake, with C _max at 423 nM and t _max at 2 h, and methyl catechin–glucuronide (301 nM, 2 h) was the main metabolite in the plasma after the PE intake. As a result of the PECC enrichment, epicatechin–glucuronide (452 nM, 1.5 h) and catechin–glucuronide (297 nM, 2 h) were the main metabolites in the plasma. Methyl catechin–glucuronide was found in the liver after PE (8 nmol/g tissue, 4 h) and PECC (8 nmol/g, 1.5 h). The kidney was found to contain a high concentration of phase-II metabolites of procyanidins and is therefore thought to be the main site of metabolism of the compounds. Methyl catechin–sulfate (6.4 nmol/g, 4 h) was only quantified in the brain and after PE intake. Catechin metabolites were not found in the spleen or heart. Phenolic acids were detected in all tissues.

Conclusions

The formulation of a product enriched or fortified with procyanidins is a way to increase their bioavailability, with clear effects on the plasmatic pharmacokinetics, and a greater accumulation of phenolic metabolites in such tissues as the liver, kidney, lung and brain.     

Antidiabetic activity of isoquercetin in diabetic KK -Ay mice

Background

Protective effects of omega-3 fatty acids against cellular damages of high glucose were studied on retinal pigmented epithelial (RPE) cells.

Methods

Retinal epithelial cells were incubated with omega-3 marine oils rich in EPA and DHA and then with high glucose (25 mM) for 48 hours. Cellular responses were compared to normal glucose (5 mM): intracellular redox status, reactive oxygen species (ROS), mitochondrial succinate deshydrogenase activity, inflammatory cytokines release and caveolin-1 expression were evaluated using microplate cytometry, ELISA and flow cytometry techniques. Fatty acids incorporation in retinal cell membranes was analysed using chromatography.

Results

Preincubation of the cells with fish oil decreased ROS overproduction, mitochondrial alterations and TNFα release. These protective effects could be attributed to an increase in caveolin-1 expression induced by marine oil.

Conclusion

Marine formulations rich in omega-3 fatty acids represent a promising therapeutic approach for diabetic retinopathy.     

The interaction between ApoA2 −265T&gt;C polymorphism and dietary fatty acids intake on oxidative stress in patients with type 2 diabetes mellitus

Introduction

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

Methods

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

Results

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

Conclusions

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

     

Biomarkers of endothelial activation and thrombosis in tunnel construction workers exposed to airborne contaminants

Objectives

The aims were to study biomarkers of systemic inflammation, platelet/endothelial activation and thrombosis in tunnel construction workers (TCW).

Methods

Biomarkers and blood fatty acids were measured in blood of 90 TCW and 50 referents before (baseline) and towards the end (follow-up) of a 12 days work period. They had been absent from work for 9 days at baseline. Air samples were collected by personal sampling.

Results

Personal thoracic air samples showed geometric mean (GM) particulate matter and α-quartz concentrations of 604 and 74 µg/m³, respectively. The arithmetic mean (AM) concentration of elemental carbon was 51 µg/m³. The GM (and 95% confidence interval) concentration of the pro-inflammatory cytokine TNF-α decreased from 2.2 (2.0–2.4) at baseline to 2.0 pg/mL (1.8–2.2) (p?=?0.02) at follow-up among the TCW. Also the platelet activation biomarkers P-selectin and CD40L decreased significantly [25.4 (24.1–26.6) to 24.4 (22.9–26.0)] ng/mL, p?=?0.04 and 125 (114–137) to 105 (96–115) pg/mL, p?<?0.001, respectively. ICAM-1 concentrations increased from 249 (238–260) to 254 (243–266) ng/mL (p?=?0.02). No significant alterations were observed among the referents when assessed by paired sample t test. Unbeneficial alterations in blood fatty acid composition were observed between baseline and follow-up, mainly among referents.

Conclusions

TCW had slightly reduced systemic inflammation and platelet activation although highly exposed to particulate matter, α-quarz and diesel exhaust, which might be due to increased physical activity during the exposure period. The slightly increased ICAM-1 may indicate monocyte recruitment to the lungs. The diet was substantially altered towards a less beneficial fatty acid profile.

     

Sense of coherence as an independent predictor of health-related quality of life among coronary heart disease patients

Purpose

The aim of this study was to determine whether sense of coherence (SOC) at baseline predicts health-related quality of life (HRQoL) at 12–28-month follow-up among patients with coronary heart disease when controlled for sociodemographic and medical variables.

Methods

A total of 179 consecutive patients (58.28 ± 6.52 years, 16.8% women) scheduled for coronary angiography (CAG) were interviewed before CAG and 12–28 months after. SOC was measured with the 13-item Orientation to Life Questionnaire. HRQoL was measured using the Short Form Health Survey 36 (SF-36), from which the mental and physical component summaries (MCS, PCS) were calculated. The relationship between SOC and HRQoL was examined using regression analyses.

Results

SOC proved to be a significant predictor of the MCS-score (B = 0.29; 95% CI = 0.17–0.41) and PCS-score (B = 0.18; 95% CI = 0.06–0.31) when not adjusted for possible confounding sociodemographic and medical variables. After adjustment for sociodemographic and medical variables, SOC remained a predictor of the MCS-score (B = 0.26; 95% CI = 0.14–0.39). SOC also remained a predictor of the PCS-score when controlled for gender, age and family income; however, the association disappeared after adjustment for functional status (B = 0.07; 95% CI = ?0.05 to 0.19).

Conclusions

SOC is a predictor of mental and physical HRQoL at 12–28-month follow-up, crude and also after adjustment. Patients undergoing CAG with low SOC thus deserve particular attention in regard to the maintenance and improvement of their HRQoL.     

Adherence to Mediterranean diet and close dietetic supervision increase total dietary antioxidant intake and plasma antioxidant capacity in subjects with abdominal obesity

Purpose

To determine the effect of Mediterranean-type diet and close dietetic supervision on dietary antioxidant intake and plasma total antioxidant capacity (TAC) in patients with abdominal obesity.

Methods

Ninety subjects with abdominal obesity, 46 in intervention group, 44 in control group, participated in a 2-month, randomized, parallel dietary intervention. All participants were counseled on Greek Mediterranean diet. The intervention group was under close dietetic supervision, followed a specific relevant daily and weekly food plan consuming antioxidant-rich foods and food products. Total dietary antioxidant intake was calculated from the volunteers’ food diaries, and plasma TAC using plasma ORAC assay and plasma ferric-reducing antioxidant power (FRAP) assay, both at baseline and at 2 months.

Results

Following the 2-month period, total dietary antioxidant intake was increased in the intervention group compared to the control group (P = 0.000). In addition, increased intake of total fat, due to higher consumption of monounsaturated fatty acids, as well as increased intakes of dietary fiber, vitamin C and alcohol was also observed in the intervention group compared to the control group (P < 0.05). Plasma TAC was increased in the intervention group compared to the control group (P = 0.039) using the ORAC assay, while there was a trend toward a TAC increase (P = 0.077) using the FRAP assay.

Conclusion

Adherence to a Mediterranean-type diet, with emphasis on an increase in foods rich in antioxidants and close dietetic supervision, can increase total dietary antioxidant intake and plasma TAC in patients with abdominal obesity.     

Olive oil improves the intestinal absorption and bioavailability of lutein in lutein-deficient mice

Purpose

To investigate the influence of olive (OO), groundnut (GNO), soybean (SBO), sunflower (SFO), rice bran (RBO), corn (CO), palm (PO) oil or mixed micelle (control) on absorption kinetics and bioavailability of lutein in lutein-deficient mice. Additional aim was to correlate the activity of intestinal triacylglycerol lipase with intestinal and plasma lutein levels.

Methods

After induction of lutein deficiency, mice (n = 165) were divided into eight groups (OO, SFO, GNO, RBO, PO, CO, SBO and control; n = 20/group) and the remaining (n = 5) were used as baseline (0 h). Groups were further divided into four subgroups (n = 5/subgroup) and were intubated with lutein (200 μM) dispersed in different vegetable oils. Plasma and tissue (intestine, liver and eyes), lutein, triglycerides, intestinal triacylglycerol lipases and fatty acid profile of plasma and tissues were measured at different time intervals.

Results

The percentage area under the curve value for plasma lutein in OO and GNO was higher by 41.8 and 5.1 %, while it was lower in other groups (18.2–53.3 %), when compared to control. Similarly, the percentage area under the curve for eye lutein in OO and GNO groups was higher by 35.2 and 4.8 %, whereas in other groups it was lower (5.4–69 %) than in control. Results show that olive oil facilitates the lutein absorption more compared to other vegetable oils, which may be due to the difference in fatty acid composition and higher activity of intestinal triacylglycerol lipase.

Conclusions

Dietary olive oil rich in oleic acid improves the bioavailability and accumulation of lutein in lutein-deficient mice by modifying the intestinal triacylglycerol lipase activity.     

The α′ subunit of β-conglycinin and the A1–5 subunits of glycinin are not essential for many hypolipidemic actions of dietary soy proteins in rats

Purpose

This study examined the effects of dietary soy protein (SP) lacking different storage protein subunits and isoflavones (ISF) on the abdominal fat, blood lipids, thyroid hormones, and enzymatic activities in rats.

Methods

Weanling Sprague–Dawley rats (8 males and 8 females/group) were fed diets containing either 20 % casein without or with supplemental isoflavones or alcohol-washed SP isolate or SP concentrates (SPC) prepared from 6 different soy bean lines for 8 weeks.

Results

Feeding of diets containing SPC regardless of their subunit compositions significantly lowered relative liver weights, blood total, free, and LDL cholesterol in both genders (P < 0.05) and also reduced serum free fatty acids (FFA) and abdominal fat in females (P < 0.05) compared to the casein or casein + ISF diets. Dietary SPC significantly elevated the plasma free triiodothyronine (T3) in both genders and total T3 in females compared to the casein diet (P < 0.05). The SPC lacking β-conglycinin α′ and either the glycinin A1–3 or A1–5 subunits increased total T3 in males and reduced plasma enzymatic activities of creatine kinase and lactate dehydrogenase compared to casein or casein + ISF diet (P < 0.05).

Conclusions

Soy isoflavones were mainly responsible for the hypocholesterolemic effects and increased plasma free T3, whereas reduction in FFA, abdominal fat, liver weight and increased plasma total T3 were the effects of the soy proteins. Neither the α′ subunit of β-conglycinin nor the A1–5 subunits of glycinin are essential for the hypolipidemic properties of soy proteins.     

Screening of soy protein-derived hypotriglyceridemic di-peptides in vitro and in vivo

Background

Postprandial lipaemia varies with gender and the composition of dietary fat due to the partitioning of fatty acids between beta-oxidation and incorporation into triacylglycerols (TAGs). Increasing evidence highlights the importance of postprandial measurements to evaluate atherogenic risk. Postprandial effects of alpha-linolenic acid (ALA) in women are poorly characterized. We therefore studied the postprandial lipid response of women to an ALA-rich oil in comparison with olive oil and butter, and characterized the fatty acid composition of total lipids, TAGs, and non-esterified fatty acids (NEFAs) in plasma.

Methods

A randomized crossover design (n = 19) was used to compare the postprandial effects of 3 meals containing 35 g fat. Blood samples were collected at regular intervals for 7 h. Statistical analysis was carried out with ANOVA (significant difference = P < 0.05).

Results

No significant difference was seen in incremental area under the curve (iAUC) plasma-TAG between the meals. ALA and oleic acid levels were significantly increased in plasma after ALA-rich oil and olive oil meals, respectively. Palmitic acid was significantly increased in plasma-TAG after the butter meal. The ratios of 18:2 n-6 to18:3 n-3 in plasma-TAGs, three and seven hours after the ALA-rich oil meal, were 1.5 and 2.4, respectively. The corresponding values after the olive oil meal were: 13.8 and 16.9; and after the butter meal: 9.0 and 11.6.

Conclusions

The postprandial p-TAG and NEFA response in healthy pre-menopausal women was not significantly different after the intake of an ALA-rich oil, olive oil and butter. The ALA-rich oil significantly affected different plasma lipid fractions and improved the ratio of n-6 to n-3 fatty acids several hours postprandially.     

Unfavourable life-course social gradient of coronary heart disease within Spain: a low-incidence welfare-state country

Objective

Social position has yet to be established as a risk factor of coronary heart disease (CHD). Our aim was to investigate an individual life-course social position gradient link with CHD incidence in the EPIC-Spain cohort.

Methods

41,066 participants, mostly 30–65 years old, and free of cardiovascular disease at baseline (1992–1996) were followed up for a mean of 10.4 years. A combined score of paternal occupation in childhood and own adult education was used to assess individual life-course risk accumulation. Hazard ratios of CHD were estimated using Cox models, stratifying by centre, and age, and adjusting for cardiovascular risk factors.

Results

583 participants (80 % men) developed a definite CHD event. Paternal occupational class IV was associated with CHD in all models in men. The educational gradient remained significant after adjusting for diet and physical activity (p = 0.01). All adjusted risk of incident CHD rose by 23 % (95 % CI 6–42 %) per category increase of life-course social position score in men. No significant associations were found in women.

Conclusions

Individual life-course social position gradient was adversely related to incident CHD in Spanish men.     

A moderate weight reduction through dietary intervention decreases hepatic fat content in patients with non-alcoholic fatty liver disease (NAFLD): a pilot study

Purpose

As a diet rich in fructose and an impaired intestinal barrier function have been proposed to be risk factors for the development of non-alcoholic fatty liver disease (NAFLD), the aim of the present pilot study was to determine whether a dietary intervention focusing on a reduction of fructose intake (?50 % in comparison with baseline) has a beneficial effect on liver status.

Methods

A total of 15 patients with NAFLD were enrolled in the study of which 10 finished the study. Fructose and total nutrient intake were assessed using a diet history. At baseline and after 6 months liver status and markers of intestinal barrier function as well as plasminogen activator inhibitor (PAI-) 1 concentration were determined in plasma.

Results

Hepatic lipid content and transaminases in plasma as well as body mass index and some parameters of glucose metabolism (e.g., fasting plasma insulin) were significantly lower at the end of the intervention when compared to baseline. Whereas the dietary intervention had no effect on the prevalence of bacterial overgrowth, orocecal transit time and the intestinal permeability or blood ethanol levels endotoxin and PAI-1 concentration in plasma were significantly lower at the end of 6 months intervention period than at baseline.

Conclusions

Taken together, our results indicate that a dietary intervention focusing only on one dietary parameter like fructose may help to decrease intrahepatic fat content of NAFLD patients.