Saturated Fatty Acids Modulate Autophagy's Proteins In The Hypothalamus.

Autophagy is an important process that regulates cellular homeostasis by degrading dysfunctional proteins, organelles and lipids. In this study, the hypothesis that obesity could lead to impairment in hypothalamic autophagy in mice was evaluated by examining the hypothalamic distribution and content of autophagic proteins in animal with obesity induced by 8 or 16 weeks high fat diet to induce obesity and in response to intracerebroventricular injections of palmitic acid. The results showed that chronic exposure to a high fat diet leads to an increased expression of inflammatory markers and downregulation of autophagic proteins. In obese mice, autophagic induction leads to the downregulation of proteins, such as JNK and Bax, which are involved in the stress pathways. In neuron cell- line, palmitate has a direct effect on autophagy even without inflammatory activity. Understanding the cellular and molecular bases of overnutrition is essential for identifying new diagnostic and therapeutic targets for obesity.

Storage stability of snacks with reduced saturated and trans fatty acids contents

A gordura vegetal parcialmente hidrogenada tem sido utilizada na aromatização de snacks. Entretanto, o risco à saúde ocasionado pelo elevado consumo de ácidos graxos saturados e trans (AGT) vem estimulando o desenvolvimento de abordagens alternativas a essa gordura. Substituímos a gordura vegetal parcialmente hidrogenada (F) por óleo de canola (O) na aromatização de snacks. Snacks com diferentes níveis de O foram produzidos, embalados e armazenados em temperatura ambiente durante vinte semanas. Monitoramos o perfil de ácidos graxos, o teor de substâncias reativas ao TBA (TBARS), a força de cisalhamento e a aceitabilidade sensorial. A substituição total reduziu o teor de ácidos graxos saturados em 72,5 por cento, em comparação aos snacks comerciais. Os snacks eram inicialmente isentos de AGT, porém, após 8 semanas, esses compostos surgiram, havendo aumento gradual durante o período de armazenamento. Entretanto, estes níveis mantiveram-se inferiores aos observados em snacks comercializados. Também foram observados baixos teores de TBARS e estabilidade da força de cisalhamento. Snacks aromatizados com F ou O foram igualmente bem aceitos durante as vinte semanas de armazenamento. É possível desenvolver snacks com teores reduzidos de ácidos graxos saturados e trans, estáveis durante o armazenamento, mantendo a elevada aceitabilidade sensorial típica deste tipo de produto

Interaction Between Polar Components and the Degree of Unsaturation of Fatty Acids on the Oxidative Stability of Emulsions

Minor components (polar components) and the degree of unsaturation of the fatty acids are the main factors responsible for the oxidative stability of bulk oils and emulsions. The isolated effects of these two factors and their interaction were evaluated in oil-in-water emulsions stored at 32 A degrees C. Samples of coconut, olive, soybean, linseed and fish oils, both full and stripped of their polar components, were used to prepare the emulsions (1% w/w). The maximum concentration of hydroperoxide (LOOH(max)) and the rate of formation of hydroperoxides (mu mol L(-1) h(-1)) were used to measure the primary products. Hexanal, propanal and malondialdehyde were used to determine the secondary products of the oxidized emulsions containing polyunsaturated fatty acids. LOOH(max) varied from 0.16 to 12.75 mmol/kg among the samples. The interaction between the polar components and the degree of unsaturation of the fatty acids was significant (p < 0.001) when the hydroperoxides were evaluated. In general, the degree of unsaturation (beta(1)) and the absence of polar components (beta(2)), respectively, represented 30 and 20% of the contribution to increase the mean oxidation, with the interaction (beta(12)) contribution being more sensitive to the rate of formation of hydroperoxides (16%) than to the LOOH(max) (5%). The significance of this interaction suggests that both strategies present synergism and should be applied to improve the oxidative stability of food emulsions.

Effect of different prebiotics on the fermentation kinetics, probiotic survival and fatty acids profiles in nonfat symbiotic fermented milk

The simultaneous effects of different binary co-cultures of Lactobacillus acidophilus, Lactobacillus bulgaricus, Lactobacillus rhamnosus and Bifidobacterium lactis with Streptococcus thermophilus and of different prebiotics on the production of fermented milk were investigated in this paper. In particular, we determined and compared the kinetics of acidification of milk either as such or supplemented with 4% (w/w) maltodextrin, oligofructose and polydextrose, as well as the probiotic survival, chemical composition (pH, lactose, lactic acid and protein contents), fatty acids profile and conjugate linoleic acid (CIA) content of fermented milk after storage at 4 degrees C for 24 h. Fermented milk quality was strongly influenced both by the co-culture composition and the selected prebiotic. Depending on the co-culture, prebiotic addition to milk influenced to different extent kinetic acidification parameters. All probiotic counts were stimulated by oligofructose and polydextrose, and among these B. lactis always exhibited the highest counts in all supplemented milk samples. Polydextrose addition led to the highest post-acidification. Although the contents of the main fatty acids were only barely influenced. the highest amounts of conjugated linoleic acid (38% higher than in the control) were found in milk fermented by S. thermophilus-L. acidophilus co-culture and supplemented with maltodextrin. (C) 2008 Elsevier B.V. All rights reserved.

Oxidation of oxa and thia fatty acids and related compounds catalysed by 5-and 15-lipoxygenase

The modified fatty acids, (Z,Z,Z)-(octadeca-6,9,12-trienyloxy)acetic acid, (Z,Z,Z)-(octadeca-9,12,15-trienyloxy)acetic acid, (all-Z)-(eicosa-5,8,11,14-tetraenyloxy)acetic acid, (all-Z)-(eicosa-5,8,11,14-tetraenylthio)acetic acid, 3-[(all-Z)-(eicosa-5,8,11,14-tetraenylthio)]propionic acid, (all-Z)-(eicosa-5,8,11,14-tetraenylthio)succinic acid, N-[(all-Z)-(eicosa-5,8,11,14-tetraenoyl)]glycine and N-[(all-Z)-(eicosa-5,8,11,14-tetraenoyl)]aspartic acid, all react with soybean 15-lipoxygenase. The products were treated with triphenylphosphine to give alcohols, which were isolated using HPLC. Analysis of the alcohols using negative ion tandem electrospray mass spectrometry, and by comparison with compounds obtained by autoxidation of arachidonic acid, shows that each enzyme catalysed oxidation occurs at the omega -6 position of the substrate. In a similar fashion, it has been found that (Z,Z,Z)-(octadeca-6,9,12-trienyloxy)acetic acid, (Z,Z,Z)-(octadeca-9,12,15-trienyloxy)acetic acid, (all-Z)-(eicosa-5,8,11,14-tetraenylthio)acetic acid and N-[(all-Z)-(eicosa-5,8, 11.14-tetraenylthio)]propionic acid each undergoes regioselective oxidation at the carboxyl end of the polyene moiety on treatment with potato 5-lipoxygenase. Neither (all-Z)-(eicosa-5,8,11,14-tetraenylthio)succinic acid nor N-[(all-Z)-(eicosa-5,8,11,14-tetraenoyl)]aspartic acid reacts in the presence of this enzyme, while N-[(all-Z)-(eicosa-5,8,11,14-tetraenoyl)]glycine affords the C11' oxidation product. The alcohol derived from (Z,Z,Z)-(octadeca-6,9, 12-trienyloxy)acetic acid using the 15-lipoxygenase reacts at the C6' position with the 5-lipoxygenase. (C) 2001 Elsevier Science Ltd. All rights reserved.

Intake of trans Fatty Acids Causes Nonalcoholic Steatohepatitis and Reduces Adipose Tissue Fat Content

We investigated the effects of dietary trans fatty acids, PUFA, and SEA on body and liver fat content, liver histology, and mRNA of enzymes involved in fatty acid metabolism. LDL receptor knockout weaning male mice were fed for 16 wk with diets containing 40% energy as either trans fatty acids (TRANS), PUFA, or SEA. Afterwards, subcutaneous and epididymal fat were weighed and histological markers of nonalcoholic fatty liver disease (NAFLD) were assessed according to the Histological Scoring System for NAFLD. PPAR alpha, PPAR gamma, microsomal triglyceride transfer protein (MTP), carnitine palmitoyl transferase 1 (CPT-1), and sterol regulatory element binding protein-1c (SREBP-1c) mRNA were measured by quantitative RT-PCR. Food intake was similar in the 3 groups, although mice fed the TRANS diet gained less weight than those receiving the PUFA diet. Compared with the PUFA- and SEA-fed mice, TRANS-fed mice had greater plasma total cholesterol (TC) and triglyceride (TG) concentrations, less epididymal and subcutaneous fat, larger livers with nonalcoholic steatohepatitis (NASH)-like lesions, and greater liver TC and TG concentrations. Macrosteatosis in TRANS-fed mice was associated with a higher homeostasis model assessment of insulin resistance (HOMA(IR)) index and upregulated mRNA related to hepatic fatty acid synthesis (SREBP-1 c and PPAR gamma) and to downregulated MTP mRNA. Diet consumption did not alter hepatic mRNA related to fatty acid oxidation (PPAR alpha and CPT-1). In conclusion, compared with PUFA- and SFA-fed mice, TRANS-fed mice had less adiposity, impaired glucose tolerance characterized by greater HOMA(IR) index, and NASH-like lesions due to greater hepatic lipogenesis. These results demonstrate the role of trans fatty acid intake on the development of key features of metabolic syndrome. J. Nutr. 140: 1127-1132, 2010.

Effects of Sleep Apnea on Nocturnal Free Fatty Acids in Subjects with Heart Failure

Study Objectives: Sleep apnea is common in patients with congestive heart failure, and may contribute to the progression of underlying heart diseae. Cardiovascular and metabolic complications of sleep apnea have been attributed to intermittent hypoxia. Elevated free fatty acids (FFA) are also associated with the progression of metabolic, vascular, and cardiac dysfunction. The objective of this study was to determine the effect of intermittent hypoxia on FFA levels during sleep in patients with heart failure. Design and interventions: During sleep, frequent blood samples were examined for FFA in patients with stable heart (ejection fraction < 40%). In patients with severe sleep apnea (apnea-hypopnea index = 15.4 +/- 3.7 events/h; average low SpO(2) = 93.6%). In patients with severe sleep apnea, supplemental oxygen at 2-4 liters/min was administered on a subsequent night to eliminate hypoxemia. Measurements and Results: Prior to sleep onset, controls and patients with severe apnea exhibited a similar FFA level. After sleep onset, patients with severe sleep apnea exhibited a marked and rapid increase in FFA relative to control subjects. This increase persisted throughout NREM and REM sleep exceeding serum FFA levels in control subjects by 0.134 mmol/L (P = 0.0038) Supplemental oxygen normalized the FFA profile without affecting sleep architecture or respiratory arousal frequency. Conclusion: In patients with heart failure, severe sleep apnea causes surges in nocturnal FFA that may contribute to the accelerated progression of underlying heart disease. Supplemental oxygen prevents that FFA elevation.

Positive impact of omega-3 fatty acid supplementation in a dog with drug-resistant epilepsy: A case study

Epilepsy is the most common neurological disorder in both dogs and humans. Although the pharmacological options for treatment of epilepsies have increased. it has been reported that two-thirds of dogs with epilepsy are refractory to antiepileptic drug therapy. To our knowledge, there are no experimental Studies in the literature that show an effect of omega-3 supplementation oil epilepsy in dogs. Our case study describes the effectiveness of daily intake of a moderate amount of fish oil in a case of canine epilepsy. (C) 2009 Elsevier Inc. All rights reserved.

The effect of volatile fatty acids in acidified fermented piggery effluent on shiga-toxigenic and non-toxic resident strains of Escherichia coli

Aims: To examine the effects of acidified acidogenically fermented piggery effluent containing Volatile Fatty Acids (VFA) on shiga-toxigenic and resident strains of Escherichia coli (E. coli) as part of the development of a waste treatment process. Methods and Results: Four shiga-toxigenic E. coli strains (O157:H7, 091.H-, 0111.H-, and 0123.H-) and four non-toxic resident enzootic strains were all killed by 3 h treatment with fermented piggery effluent liquor (153 mmol l(-1) total VFA) at pH 4.3. The shiga-toxigenic strains showed greater sensitivity after 1 h of treatment. The fermented liquor at pH 6.8 was not inhibitory. Conclusions: The shiga-toxigenic strains were no more resistant to the toxic effects of VFA than the non-toxic strains tested. Significance and Impact of the Study: Shiga-toxigenic strains and resident enzootic non-toxigenic strains are equally susceptible to inactivation by this waste treatment process and by acidified VFA in general.

Effects of polyunsaturated fatty acids on voltage-gated K+ and Na+ channels in rat olfactory receptor neurons

Although the polyunsaturated fatty acids arachidonic acid (AA) and docosahexaenoic acid (DHA) are enriched in the olfactory mucosa, their possible contribution to olfactory transduction has not been investigated. This study characterized their effects on voltage-gated K+ and Na+ channels of rat olfactory receptor neurons. Physiological (3-10 mum) concentrations of AA and DHA potently and irreversibly inhibited the voltage-gated K+ current in a voltage-independent manner. In addition, both compounds significantly reduced the inhibitory potency of the odorants acetophenone and amyl acetate at these channels. By comparison, the steady-state effects of both AA and DHA on the voltage-gated Na+ channel were relatively weak, with half-maximal inhibition requiring approximate to 35 mum of either compound. However, a surprising finding was that the initial application of 3 mum AA to a naive neuron caused a strong but transient inhibition of the Na+ current. The channels became almost completely resistant to this inhibition within 1 min, and a 2-min wash in control solution was insufficient to restore the strong inhibitory effect. These observations suggest that polyunsaturated fatty acids have the potential to strongly influence the coding of odorant information by olfactory receptor neurons.

Fatty acids, IL6, and TNFα polymorphisms: an example of nutrigenetics in Crohn's disease

Objectives - The aim of this work was to study the interaction between genetic polymorphisms (single-nucleotide polymorphisms, SNPs) of pro- and anti-inflammatory cytokines and fat intake on the risk of developing Crohn's disease (CD) or modifying disease activity. Methods - Seven SNPs in interleukin 1 (IL1), tumor necrosis factor alpha (TNFalpha), lymphotoxin alpha (LTalpha), and IL6 genes were analyzed in 116 controls and 99 patients with CD. The type of fat intake was evaluated, and the interaction between SNPs and dietary fat in modulating disease activity was analyzed. Results - Individuals who were homozygous for the IL6-174G/C polymorphism had a six-fold higher risk for CD (odds ratio (OR)=6.1; 95% confidence interval (95% CI)=1.9-19.4), whereas the TT genotype on the TNFalpha-857C/T polymorphism was associated with more active disease (OR=10.4; 95% CI=1.1-94.1). A high intake of total, saturated, and monounsaturated fats, as well as a higher ratio of n-6/n-3 polyunsaturated fatty acid (PUFA), was associated with a more active phenotype (P<0.05). Furthermore, there was an interaction between dietary fat intake and SNPs, with a high intake of saturated and monounsaturated fats being associated with active disease, mainly in patients carrying the variant alleles of the 857 TNFalpha polymorphism (OR=6.0, 95% CI=1.4-26.2; OR=5.17; 95% CI=1.4-19.2, respectively) and the 174 IL6 polymorphism (OR=2.95; 95% CI=1.0-9.1; OR=3.21; 95% CI=1.0-10.4, respectively). Finally, low intake of n-3 PUFA and high n-6/n-3 PUFA ratio in patients with the TNFalpha 857 polymorphism were associated with higher disease activity (OR=3.6; 95% CI=1.0-13.0; OR=5.92; 95% CI=1.3-26.5, respectively). Conclusions - These results show that different types of fat may interact with cytokine genotype, modulating disease activity.

The effect of long-chain polyunsaturated fatty acids intake during pregnancy on adiposity of healthy full-term offspring at birth

Objective - The adjusted effect of long-chain polyunsaturated fatty acid (LCPUFA) intake during pregnancy on adiposity at birth of healthy full-term appropriate-for-gestational age neonates was evaluated. Study Design - In a cross-sectional convenience sample of 100 mother and infant dyads, LCPUFA intake during pregnancy was assessed by food frequency questionnaire with nutrient intake calculated using Food Processor Plus. Linear regression models for neonatal body composition measurements, assessed by air displacement plethysmography and anthropometry, were adjusted for maternal LCPUFA intakes, energy and macronutrient intakes, prepregnancy body mass index and gestational weight gain. Result - Positive associations between maternal docosahexaenoic acid intake and ponderal index in male offspring (β=0.165; 95% confidence interval (CI): 0.031–0.299; P=0.017), and between n-6:n-3 LCPUFA ratio intake and fat mass (β=0.021; 95% CI: 0.002–0.041; P=0.034) and percentage of fat mass (β=0.636; 95% CI: 0.125–1.147; P=0.016) in female offspring were found. Conclusion - Using a reliable validated method to assess body composition, adjusted positive associations between maternal docosahexaenoic acid intake and birth size in male offspring and between n-6:n-3 LCPUFA ratio intake and adiposity in female offspring were found, suggesting that maternal LCPUFA intake strongly influences fetal body composition.