Reference values of whole-blood fatty acids by age and sex from European children aged 3-8 years

OBJECTIVES: To establish reference values for fatty acids (FA) especially for n-3 and n-6 long-chain polyunsaturated FAs (LC PUFA) in whole-blood samples from apparently healthy 3-8-year-old European children. The whole-blood FA composition was analysed and the age-and sex-specific distribution of FA was determined. DESIGN AND SUBJECTS: Blood samples for FA analysis were taken from 2661 children of the IDEFICS (identification and prevention of dietary-and lifestyle-induced health effects in children and infants) study cohort. Children with obesity (n = 454) and other diseases that are known to alter the FA composition (n = 450) were excluded leaving 1653 participants in the reference population. MEASUREMENTS: The FA composition of whole blood was analysed from blood drops by a rapid, validated gas chromatographic method. RESULTS: Pearson correlation coefficients showed an age-dependent increase of C18:2n-6 and a decrease of C18:1n-9 in a subsample of normal weight boys and girls. Other significant correlations with age were weak and only seen either in boys or in girls, whereas most of the FA did not show any age dependence. For age-dependent n-3 and n-6 PUFA as well as for other FA that are correlated with age (16:0, C18:0 and C18:1n-9) percentiles analysed with the general additive model for location scale and shape are presented. A higher median in boys than in girls was observed for C20:3n-6, C20:4n-6 and C22:4n-6. CONCLUSIONS: Given the reported associations between FA status and health-related outcome, the provision of FA reference ranges may be useful for the interpretation of the FA status of children in epidemiological and clinical studies

Eight-week consumption of milk enriched with omega 3 fatty acids raises their blood concentrations yet does not affect lipids and cardiovascular disease risk factors in adult healthy volunteers

Adequate concentrations of omega 3 fatty acids (FA) may be maintained by consuming foods naturally rich in or functional foods enriched with those essential FA. We assessed the effects of an 8-week consumption of milk enriched with 400. mg of omega 3 FA on blood lipid levels and selected cardiovascular risk factors in adult healthy volunteers. Participants (n= 157) were randomized to consume - for eight weeks - either 500. mL/day of 1% fat milk providing 150. mg of eicosapentaenoic (EPA), 150. mg of docosahexaenoic (DHA), and 100. mg of α-linolenic (ALA) acids or 500. mL/day of non-enriched 1% fat milk. At week 8, we observed significant increments of blood EPA and DHA in the intervention group and a decrease in controls. No significant between-group differences at week 8 were observed in the lipid profile and other surrogate makers of cardiovascular disease, with the exception of homocysteine, whose levels remained stable in the intervention group, but increased in the control group (p<. 0.001). In conclusion, daily consumption of 500. mL of 1% fat milk enriched with omega-3 FA for eight weeks leads to higher blood levels of EPA and DHA, confirming that milk is an optimal matrix for the provision of important micronutrients

Blood N-3 fatty acids increase after consumption of an enriched yoghurt

The effects of a n-3 fatty acid (FA) enriched yoghurt on blood FA were investigated in 23 females and 23 males, who consumed 2 yoghurts/day for 6 weeks, providing 64 mg EPA and 74 mg DHA. Blood samples were collected before treatment, at the beginning, end, and after wash out. Yoghurt intakes increased blood EPA (35%) and DHA (11%) with different trends of changes in women versus men. In conclusion, the daily consumption of a yoghurt containing small amounts of n-3 FA significantly increases blood n-3 FA, providing a useful approach to reach the recommended intakes in populations

Docosahexaenoic acid supplementation decreases liver fat content in children with non-alcoholic fatty liver disease: Double-blind randomised controlled clinical trial

Objective: To investigate whether dietary supplementation with docosahexaenoic acid (DHA) decreases liver fat content in children with non-alcoholic fatty liver disease (NAFLD). Design, setting and patients: We performed a randomised controlled trial of DHA supplementation (250 and 500 mg/day) versus placebo in 60 children with biopsy-proven NAFLD (20 children per group). Main outcome measures: The main outcome was the change in liver fat content as detected by ultrasonography after 6 months of treatment. Secondary outcomes were the changes in insulin sensitivity index, alanine transaminase, triglycerides and body mass index after 6 months of treatment. Results: Blood DHA increased in children supplemented with DHA (0.65%, 95% CI 0.30% to 1.10% for the DHA 250 mg group and 1.15%, 0.87% to 1.43% for the DHA 500 mg group). The odds of more severe versus less severe liver steatosis after treatment was lower in children treated with DHA 250 mg/day (OR = 0.01, 0.002 to 0.11, p ̃ <0.001) and DHA 500 mg/day (OR = 0.04, 0.002 to 0.46, p = 0.01) as compared to placebo but there was no difference between the DHA groups (p = 0.4). Insulin sensitivity index increased and triglycerides decreased to a similar degree in both DHA groups as compared to placebo but there was no effect on alanine transaminase and body mass index. Conclusion: DHA supplementation improves liver steatosis and insulin sensitivity in children with NAFLD

Fatty acid profiles of blood lipids in a population group in Tibet : correlations with diet and environmental conditions

The aim of the study was to compare blood fatty acid profiles of two population groups: Italian and Tibetan, differing with regard to ethnic, life style and environmental aspects. Additionally the collection of two staple foods provided the opportunity to analyze typical Tibetan dishes. A new, simple, rapid, and substantially non invasive method for fatty acid (FA) analysis of blood lipids was applied to healthy Italian (n= 14) and Tibetan (n= 13) subjects. Blood drops obtained from the ear lobe of Tibetans or the fingertip of Italians were adsorbed by a special strip of paper and processed for fatty acid analysis. The fatty acid profiles of the two groups are different, and environmental factors, such as dietary fats and altitudes of the two locations Milan, Italy (a low altitude site), and Lhasa, Tibet (a high altitude site) appear to contribute to these differences. More specifically, in Tibetans higher levels of monounsaturated fatty acids including the 22 and 24 carbon molecules, were found. This appears to be derived mainly from locally consumed fats (mustard seed oil), and are associated with lower levels of total polyunsaturated fatty acids and higher levels of selected omega 3 fatty acids, when compared to the Italians. These relatively higher levels of monounsaturated fatty acids may also indicate means of adaptation to local prooxidant conditions. The observed differences in blood fatty acid profiles in Tibetans vs Italians appear to result both from dietary factors and adaptation to local environmental conditions such as the high altitude of the Tibetan locatio

Very low density lipoprotein-mediated signal transduction and plasminogen activator inhibitor type 1 in cultured HepG2 cells

In normal subjects and in patients with cardiovascular disease, plasma triglycerides are positively correlated with plasminogen activator inhibitor type 1 (PAI-1) levels. Moreover, in vitro studies indicate that VLDLs induce PAI-1 synthesis in cultured cells, ie, endothelial and HepG2 cells. However, the signaling pathways involved in the effect of VLDL on PAI-1 synthesis have not yet been investigated. We report that VLDLs induce a signaling cascade that leads to an enhanced secretion of PAI-1 by HepG2 cells. In myo-[(3)H]inositol-labeled HepG2 cells, VLDL (100 microg/mL) caused a time-dependent increase in [(3)H]inositol phosphates, the temporal sequence being tris>bis>monophosphate. VLDL brought about a time-dependent stimulation of membrane-associated protein kinase C (PKC) activity and arachidonate release. Finally, VLDL stimulated mitogen-activated protein (MAP) kinase, and this effect was reduced by 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H7), which suggests that PKC plays a pivotal role in MAP kinase phosphorylation. VLDL-induced PAI-1 secretion was completely prevented by U73122, a specific inhibitor of phosphatidylinositol-specific phospholipase C, by H7 or by PKC downregulation, and by mepacrine (all P<0.01 versus VLDL-treated cells). 3,4,5-Trimethoxybenzoic acid 8-(diethylamino)-octyl ester, which prevents Ca2+ release from intracellular stores, inhibited VLDL-induced PAI-1 secretion by 60% (P<0.05), and the MAP kinase/extracellular signal-regulated kinase kinase (MEK) inhibitor PD98059 completely suppressed both basal and VLDL-induced PAI-1 secretion. These data demonstrate that VLDL-induced PAI-1 biosynthesis results from a principal signaling pathway involving PKC-mediated MAP kinase activation

Very low density lipoprotein-mediated signal transduction and plasminogen activator inhibitor type 1 in cultured HepG2 cells

In normal subjects and in patients with cardiovascular disease, plasma triglycerides are positively correlated with plasminogen activator inhibitor type 1 (PAI-1) levels. Moreover, in vitro studies indicate that VLDLs induce PAI-1 synthesis in cultured cells, ie, endothelial and HepG2 cells. However, the signaling pathways involved in the effect of VLDL on PAI-1 synthesis have not yet been investigated. We report that VLDLs induce a signaling cascade that leads to an enhanced secretion of PAI-1 by HepG2 cells. In myo-[(3)H]inositol-labeled HepG2 cells, VLDL (100 microg/mL) caused a time-dependent increase in [(3)H]inositol phosphates, the temporal sequence being tris>bis>monophosphate. VLDL brought about a time-dependent stimulation of membrane-associated protein kinase C (PKC) activity and arachidonate release. Finally, VLDL stimulated mitogen-activated protein (MAP) kinase, and this effect was reduced by 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H7), which suggests that PKC plays a pivotal role in MAP kinase phosphorylation. VLDL-induced PAI-1 secretion was completely prevented by U73122, a specific inhibitor of phosphatidylinositol-specific phospholipase C, by H7 or by PKC downregulation, and by mepacrine (all P<0.01 versus VLDL-treated cells). 3,4,5-Trimethoxybenzoic acid 8-(diethylamino)-octyl ester, which prevents Ca2+ release from intracellular stores, inhibited VLDL-induced PAI-1 secretion by 60% (P<0.05), and the MAP kinase/extracellular signal-regulated kinase kinase (MEK) inhibitor PD98059 completely suppressed both basal and VLDL-induced PAI-1 secretion. These data demonstrate that VLDL-induced PAI-1 biosynthesis results from a principal signaling pathway involving PKC-mediated MAP kinase activation