Effects of short chain fatty acids on effector mechanisms of neutrophils

Short chain fatty acids (SCFAs) are metabolic by products of anerobic bacteria fermentation. These fatty acids, despite being an important fuel for colonocytes, are also modulators of leukocyte function. The aim of this study was to evaluate the effects of SCFAs (acetate, propionate, and butyrate) on function of neutrophils, and the possible mechanisms involved. Neutrophils obtained from rats by intraperitoneal lavage 4 h after injection of oyster glycogen solution (1%) were treated with non toxic concentrations of the fatty acids. After that, the following measurements were performed: phagocytosis and destruction of Candida albicans, production of ROS (O(2)(center dot-), H(2)O(2), and HOCl) and degranulation. Gene expression (p47(phox) and p22(phox)) and protein phosphorylation (p47(phox)) were analyzed by real time reverse transcriptase chain reaction (RT-PCR) and Western blotting, respectively. Butyrate inhibited phagocytosis and killing of C. albicans. This SCFA also had an inhibitory effect on production of O(2)(center dot-), H(2)O(2), and HOCI by neutrophils stimulated with PMA or fMLP. This effect of butyrate was not caused by modulation of expression of NADPH oxidase subunits (p47(phox) and p22(phox)) but it was in part due to reduced levels of p47(phox) phosphorylation and an increase in the concentration of cyclic AMP. Acetate increased the production of O(2)(center dot-) and H(2)O(2), in the absence of stimuli but had no effect on phagocytosis and killing of C. albicans. Propionate had no effect on the parameters studied. These results suggest that butyrate can modulate neutrophil function, and thus could be important in inflammatory neutrophil-associated diseases. Copyright (C) 2008 John Wiley & Sons, Ltd.

Modulatory effect of fatty acids on fungicidal activity, respiratory burst and TNF-alpha and IL-6 production in J774 murine macrophages

The reported effects of different families of fatty acids (FA; SFA, MUFA, n-3 and n-6 PUFA) on human health and the importance of macrophage respiratory burst and cytokine release to immune defence led us to examine the influence of palmitic acid (PA), oleic acid (OA), linoleic acid, arachidonic acid, EPA and DHA on macrophage function. We determined fungicidal activity, reactive oxygen species (ROS) and cytokine production after the treatment of J774 cells with non-toxic concentrations of the FA. PA had a late and discrete stimulating effect on ROS production, which may be associated with the reduced fungicidal activity of the cells after treatment with this FA. OA presented a sustained stimulatory effect on ROS production and increased fungicidal activity of the cells, suggesting that enrichment of diets with OA may be beneficial for pathogen elimination. The effects of PUFA on ROS production were time-and dose-dependently regulated, with no evident differences between n-3 and n-6 PUFA. It was worth noting that most changes induced after stimulation of the cells with lipopolysaccharide were suppressed by the FA. The present results suggest that supplementation of the diet with specific FA, not classes of FA, might enable an improvement in host defence mechanisms or a reduction in adverse immunological reactions.

Molecular Mechanisms by Which Saturated Fatty Acids Modulate TNF-alpha Expression in Mouse Macrophage Lineage

Many macrophage functions are modulated by fatty acids (FAs), including cytokine release, such as tumor necrosis factor-alpha (TNF-alpha). TNF-alpha is of great interest due to its role in the inflammation process observed in several diseases such as rheumatoid arthritis, atherosclerosis, and obesity. However, the mechanisms by which FA effects occur have not been completely elucidated yet. In this study, we used a mouse monocyte lineage (J774 cells) to evaluate the effect of 50 and 100 mu M of saturated (palmitic and stearic acids), monounsaturated (oleic acid) and polyunsaturated (linoleic acid) FAs on TNF-alpha production. Alterations in gene expression, poly(A) tail length and activation of transcription factors were evaluated. Oleic and linoleic acids, usually known as neutral or pro-inflammatory FA, inhibited LPS-induced TNF-alpha secretion by the cells. Saturated FAs were potent inducers of TNF-alpha expression and secretion under basal and inflammatory conditions (in the presence of LPS). Although the effect of the saturated FA was similar, the mechanism involved in each case seem to be distinct, as palmitic acid increased EGR-1 and CREB binding activity and stearic acid increased mRNA poly(A) tail. These results may contribute to the understanding of the molecular mechanisms by which saturated FAs modulate the inflammatory response and may lead to design of associations of dietary and pharmacological strategies to counteract the pathological effects of TNF-alpha.

Lymphocytes transfer [(14)C]-labeled fatty acids to skeletal muscle in culture; modulation by exercise

Previous studies have shown that lipids are transferred from lymphocytes (Ly) to different cell types including macrophages. enterocytes, and pancreatic beta cells in co-culture This study investigated whether [(14)C]-labeled fatty acids (FA) can be transferred from Ly to skeletal muscle (SM), and the effects of exercise on such phenomenon Ly obtained from exercised (EX) and control (C) male Wistar rats were preloaded with the [(14)C]-labeled free FA palmitic (PA), oleic (OA), linoleic (LA), or arachidonic (AA) Radioactively loaded Ly were then co-cultured with SM from the same Ly donor animals Substantial amounts of FA were transferred to SM being the profile PA = OA > AA > LA to the C group. and PA > OA > LA > AA to the EX group These FA were incorporated predominantly as phospholipids (PA = 66 75%: OA = 63 09%, LA = 43 86%, AA - 47 40%) in the C group and (PA = 63 99% OA = 52 72%, LA = 55 99%, AA = 63 40%) in the EX group Also in this group, the remaining radioactivity from AA, LA, and OA acids was mainly incorpoiated in structural and energetic lipids These results support the hypothesis that Ly are able to export lipids to SM in co-culture Furthermore. exercise modulates the lipid transference profile, and its incorporation on SM The overall significance of this phenomenon in vivo remains to be elucidated. Copyright (C) 2010 John Wiley & Sons, Ltd

Suppressive effect of short-chain fatty acids on production of proinflammatory mediators by neutrophils

Short chain fatty acids (SCFAs) are fermentation products of anaerobic bacteria. More than just being an important energy source for intestinal epithelial cells, these compounds are modulators of leukocyte function and potential targets for the development of new drugs. The aim of this study was to evaluate the effects of SCFAs (acetate, propionate and butyrate) on production of nitric oxide (NO) and proinflammatory cytokines [tumor necrosis factor alpha (TNF-alpha) and cytokine-induced neutrophil chemoattractant-2 (CINC-2 alpha beta)] by rat neutrophils. The involvement of nuclear factor kappa B (NF-kappa B) and histone deacetylase (HDAC) was examined. The effect of butyrate was also investigated in vivo after oral administration of tributyrin (a pro-drug of butyrate). Propionate and butyrate diminished TNF-alpha, CINC-2 alpha beta and NO production by LPS-stimulated neutrophils. We also observed that these fatty acids inhibit HDAC activity and NF-kappa B activation, which might be involved in the attenuation of the LPS response. Products of cyclooxygenase and 5-lipoxygenase are not involved in the effects of SCFAs as indicated by the results obtained with the inhibitors of these enzymes. The recruitment of neutrophils to the peritonium after intraperitoneal administration of a glycogen solution (1%) and the ex vivo production of cytokines and NO by neutrophils were attenuated in rats that previously received tributyrin. These results argue that this triglyceride may be effective in the treatment of inflammatory conditions. Crown Copyright (C) 2011 Published by Elsevier Inc. All rights reserved.

Short-chain fatty acids stimulate the migration of neutrophils to inflammatory sites

SCFAs (short-chain fatty acids) are produced by anaerobic bacterial fermentation. Increased concentrations of these fatty acids are observed in inflammatory conditions, such as periodontal disease, and at sites of anaerobic infection. In the present study, the effect of the SCFAs acetate, propionate and butyrate on neutrophil chemotaxis and migration was investigated. Experiments were carried out in rats and in vitro. The following parameters were measured: rolling, adherence, expression of adhesion molecules in neutrophils (L-selectin and beta 2 integrin), transmigration, air pouch influx of neutrophils and production of cytokines [CINC-2 alpha beta (cytokine-induced neutrophil chemoattractant-2 alpha beta), IL-1 beta (interleukin-1 beta), MIP-1 alpha (macrophage inflammatory protein-1 alpha) and TNF-alpha (tumour necrosis factor-alpha)]. SCFAs induced in vivo neutrophil migration and increased the release of CINC-2 alpha beta into the air pouch. These fatty acids increased the number of rolling and adhered cells as evaluated by intravital microscopy. SCFA treatment increased L-selectin expression on the neutrophil surface and L-selectin mRNA levels, but had no effect on the expression of beta 2 integrin. Propionate and butyrate also increased in vitro transmigration of neutrophils. These results indicate that SCFAs produced by anaerobic bacteria raise neutrophil migration through increased L-selectin expression on neutrophils and CINC-2 alpha beta release.

Optimization of the physical refining of sunflower oil concerning the final contents of trans-fatty acids

The final contents of total and individual trans-fatty acids of sunflower oil, produced during the deacidification step of physical refining were obtained using a computational simulation program that considered cis-trans isomerization reaction features for oleic, linoleic, and linolenic acids attached to the glycerol part of triacylglycerols. The impact of process variables, such as temperature and liquid flow rate, and of equipment configuration parameters, such as liquid height, diameter, and number of stages, that influence the retention time of the oil in the equipment was analyzed using the response-surface methodology (RSM). The computational simulation and the RSM results were used in two different optimization methods, aiming to minimize final levels of total and individual trans-fatty acids (trans-FA), while keeping neutral oil loss and final oil acidity at low values. The main goal of this work was to indicate that computational simulation, based on a careful modeling of the reaction system, combined with optimization could be an important tool for indicating better processing conditions in industrial physical refining plants of vegetable oils, concerning trans-FA formation.

Quality of polyunsaturated fatty acids in Nile tilapias (Oreochromis niloticus) fed with vitamin E supplementation

Freshwater fish are an important source of protein, but they also contain other highly nutritive components such as fats. Polyunsaturated fatty acids (PUFAs) are essential for normal growth, development and reproduction of vertebrates. The antioxidant role of vitamin E in cell membranes prevents fatty acid and cholesterol oxidation, thereby promoting PUFA and subcellular particle stabilization. The effects of vitamin E supplementation on the quality of Nile tilapia (Oreochromis niloticus) carcass were investigated. The experiments were carried out in an experimental laboratory over 106 d. After sex reversal, 400 early juvenile O. niloticus were tested in a completely randomized experiment with 5 treatments (4 repetitions each), consisting of vitamin E monophosphate supplementation at 0, 50, 100, 150 or 200 mg/kg of a base diet. Treatment diets contained equal amounts of protein and energy. Tilapias supplemented with vitamin E contained arachidonic acid (20:4 omega-6; AA) which participates in inflammatory response. Nile tilapia carcasses that received vitamin E at 100 and 150 mg/kg diet had improved carcass quality by increasing the PUFA:SFA ratio and had the highest levels of polyunsaturated fatty acids from the omega-3 (linolenic acid; 18:3 omega-3) and omega-6 (linoleic acid; 18:2 omega-6) series. (C) 2012 Elsevier Ltd. All rights reserved.

Kinetics of chronic inflammation in Nile tilapia fed n-3 and n-6 essential fatty acids

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of polyunsaturated fatty acids on the fecundity of the Amazon river prawn Macrobrachium amazonicum (Heller, 1862)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Decreased oxidative stress in patients with ulcerative colitis supplemented with fish oil omega-3 fatty acids

OBJECTIVE: the potential pathogenicity of free radicals may have a pivotal role in ulcerative colitis. Fish oil omega-3 fatty acids exert anti-inflammatory effects on patients with ulcerative colitis (UC), but the precise mechanism of the action of fish oil on oxidative stress is still controversial. The aim of the present work was to verify the blood oxidative stress in patients with UC and determine whether the association of sulfasalazine to fish oil omega-3 fatty acids is more effective than isolated use of sulfasalazine to reduce the oxidative stress.METHODS:, Nine patients (seven female and two male; me. an age = 40 +/- 11 y) with mild or moderate active UC were studied in a randomized crossover design. In addition to their usual medication (2 g/d of sulfasalazine), they received fish oil omega-3 fatty acids (4.5 g/d) or placebo for 2-mo treatment periods that were separated by 2 mo, when they only received sulfasalazine. Nine healthy individuals served as control subjects to study the oxidative stress status. Disease activity was assessed by laboratory indicators (C-reactive protein, alpha(1)-acid glycoprotein, alpha(1)-antitrypsin, erythrocyte sedimentation rate, albumin, hemoglobin, and platelet count), sigmoidoscopy, and histology scores. Analysis of oxidative stress was assessed by plasma chemiluminescence and erythrocyte lipid peroxidation, both induced by tert butyl hydroperoxide (t-BuOOH) and by plasma malondialdehyde. Antioxidant status was assayed by total plasma antioxidant capacity (TRAP) and microsomal lipid peroxidation inhibition (LPI). Superoxide dismutase (SOD) and catalase erythrocyte enzymatic activities were also determined.RESULTS: No significant changes were observed in any laboratory indicator or in the sigmoidoscopy or histology scores, with the exception of erythrocyte sedimentation rate, which decreased with both treatments. Oxidative stress was demonstrated by significant decreases in TRAP and LPI levels, increased chemiluminescence induced by t-BuOOH, and higher SOD activity in patients with UC. Treatment with fish oil omega-3 fatty acids reverted the chemiluminescence induced by t-BuOOH and LPI to baseline levels but that did not occur when patients received only sulfasalazine. Levels of plasma malondialdehyde, erythrocyte lipid peroxidation, and catalase were not different from those in the control group.CONCLUSIONS: the results indicated that plasma oxidative stress occurs in patients with UC, and there was a significant decrease when the patients used sulfasalazine plus fish oil omega-3 fatty acids. However, there was no improvement in most laboratory indicators, sigmoidoscopy, and histology scores. The results suggested that omega-3 fatty acids may act as free radical scavengers protecting the patients against the overall effect of oxidative stress. (C)Elsevier B.V. 2003.

Comparison of omega-3 fatty acids and sulfasalazine in ulcerative colitis

Fish oil omega-3 fatty acids exert antiinflammatory effects on patients with ulcerative colitis. However, a comparative study in patients with mild to moderate ulcerative colitis receiving only sulfasalazine or omega-3 fatty acids has not been performed. We sought to detect changes in the inflammatory disease activity with the use of either fish oil omega-3 fatty acids or sulfasalazine in patients with ulcerative colitis. Ten patients (five male, five female; mean age = 48 +/- 12 y) with mild to moderate active ulcerative colitis were investigated in a randomized cross-over design. They received either sulfasalazine (2 g/d) or omega-3 fatty acids (5.4 g/d) for 2 mo. Disease activity was assessed by clinical and laboratory indicators, sigmoidoscopy, histology, and whole-body protein turnover (with N-15-glycine). Treatment with w-3 fatty acids resulted in greater disease activity as detected by a significant increase in platelet count, erythrocyte sedimentation rate, C-reactive protein, and total fecal nitrogen excretion. No major changes in protein synthesis and breakdown were observed during either treatment. In conclusion, treatment with sulfasalazine is superior to treatment with omega-3 fatty acids in patients with mild to moderate active ulcerative colitis. Nutrition 2000;16:87-901 (C) Elsevier B.V. 2000.

Effects of intravenous glucose infusion and nutritional balance on serum concentrations of nonesterified fatty acids, glucose, insulin, and progesterone in nonlactating dairy cows

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Strategic supplementation of calcium salts of polyunsaturated fatty acids to enhance reproductive performance of Bos indicus beef cows

Five experiments evaluated the effects of supplemental Ca salts of PUFA on reproductive function of Bos indicus beef cows. In Exp. 1, nonlactating and multiparous grazing cows (n = 51) were assigned to receive (as-fed basis) 0.1 kg of a protein-mineral mix + 0.1 kg of ground corn per cow/d, in addition to 0.1 kg per cow/d of 1) Ca salts of PUFA (PF), 2) Ca salts of SFA (SF), or 3) kaolin (control). Treatments were offered from d 0 to 20 of the estrous cycle. No treatment effects were detected on serum progesterone concentrations (P = 0.83), day of luteolysis (P = 0.86), or incidence of short cycles (P = 0.84). In Exp. 2, nonlactating and multiparous grazing cows (n = 43) were assigned to receive PF, SF, or control from d 0 to 8 of the estrous cycle. on d 6, all cows received (intramuscularly) 25 mg of PGF(2 alpha). No treatment effects were detected on serum progesterone concentrations on d 6 (P = 0.37), and incidence (P = 0.67) or estimated time of luteolysis (P = 0.44). In Exp. 3, twenty-seven lactating and multiparous grazing cows, approximately 30 to 40 d postpartum, were assigned to receive PF or control for 10 d beginning at the first postpartum ovulation. No treatment effects were detected (P = 0.85) on incidence of short cycles. In Exp. 4, lactating and multiparous grazing cows (n = 1,454), approximately 40 to 60 d postpartum, were assigned to receive 1 of the 7 treatments for 28 d after timed AI (TAI; d 0): 1) control from d 0 to 28, 2) SF from d 0 to 14 and then control, 3) PF from d 0 to 14 and then control, 4) SF from d 0 to 21 and then control, 5) PF from d 0 to 21 and then control, 6) SF from d 0 to 28, and 7) PF from d 0 to 28. Cows receiving PF for more than 21 d after TAI had greater (P < 0.01) pregnancy to TAI compared with all other treatments combined (50.4 vs. 42.4%, respectively). In Exp. 5, lactating and multiparous grazing cows (n = 501), approximately 40 to 60 d postpartum, were assigned to receive 1 of the 4 treatments for 21 d after TAI (d 0): 1) PF from d 0 to 14 and then control, 2) control from d 0 to 6 and then PF, 3) control from d 0 to 13 and then PF, and 4) PF from d 0 to 21. Cows receiving PF after d 14 of the experiment had greater (P = 0.02) pregnancy to TAI compared with cows not receiving PF during the same period (46.8 vs. 33.1%, respectively). In summary, supplemental Ca salts of PUFA during the expected time of luteolysis increased pregnancy to TAI in beef cows.