29 resultados para Fatty degeneration.
Resumo:
The fatty acid composition of immune cells appears to contribute to variations of cell function. The independent and combined effects of a single session of exercise (SSE) and glutamine supplementation (GS) on neutrophil fatty acid composition were investigated. Compared to control (no treatment given - i.e. neither SSE or GS), single session of exercise decreased myristic, palmitic and eicosapentaenoic (EPA) acids, and increased lauric, oleic, linoleic, arachidonic (AA) and docosahexaenoic (DHA) acids whereas glutamine supplementation combined with SSE (GS+SSE) increased oleic acid. Polyunsaturated/saturated fatty acid ratio and Unsaturation index were higher in neutrophils from the SSE and GS groups as compared with control. These findings support the proposition that SSE and GS may modulate neutrophil function through alterations in fatty acid composition.
Resumo:
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.
Resumo:
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
Resumo:
Interleukin-10 (IL-10) is an endogenous factor that restrains hepatic insulin resistance in diet-induced steatosis Reducing IL-10 expression increases proinflammatory activity in the steatotic liver and worsens insulin resistance As the transcriptional coactivator proliferator-activated receptor gamma coactivator-1 alpha (PGC-1 alpha) plays a central role in dysfunctional hepatocytic activity in diet-induced steatosis, we hypothesized that at least part of the action of PGC-1 alpha could be mediated by reducing the transcription of the IL-10 gene Here, we used immunoblotting, real-time polymerase chain reaction, immunocytochemistry, and chromatin immunoprecipitation assay to investigate the role of PGC-1 alpha in the control of IL-10 expression in hepatic cells First, we show that, in the intact steatotic liver, the expressions of IL-10 and PGC-1 alpha are increased Inhibiting PGC-1 alpha expression by antisense oligonucleotide increases IL-10 expression and reduces the steatotic phenotype. In cultured hepatocytes, the treatment with saturated and unsaturated fatty acids increased IL-10 expression. This was accompanied by increased association of PGC-1 alpha with c-Maf and p50-nuclear factor (NF) kappa B, 2 transcription factors known to modulate IL-10 expression In addition, after fatty acid treatment. PGC-1 alpha, c-Maf, and p50-NF kappa B migrate from the cytosol to the nuclei of hepatocytes and bind to the IL-10 promoter region Inhibiting NF kappa B activation with salicylate reduces IL-10 expression and the association of PGC-1 alpha with p50-NF kappa B Thus, PGC-1 alpha emerges as a potential transcriptional regulator of the inflammatory phenomenon taking place in the steatotic liver (C) 2010 Elsevier Inc All rights reserved
Resumo:
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.
Resumo:
Fatty acid (FA) composition of nine organs from two closely related Antarctic fish species, Notothenia codiceps and Notothenia rossii, was determined through gas chromatography with flame ionization detection. A data set for each species was obtained using major FA profiles from specimens caught in the sea waters of Admiralty Bay during the summer season. The FA profiles for both species are overall similar, but organ peculiarities have been found, which could reflect metabolic specificities and feeding habits between species. With the exception of liver, the most abundant FA in organs was the n-3 polyunsaturated FA. The total n-6 polyunsaturated FAs were minor components in all evaluated organs. Palmitic acid was identified as the major saturated FA, whereas oleic acid was the most represented of the monounsaturated FA in almost all assessed organs of both species. The n-3/n-6 ratios of all organs were higher than 3.5. Differences in individual FA and FA metabolic profiles of some organs observed between N. coriiceps and N. rossii suggest specific requirements in the mobilization, transport, incorporation, and/or catabolism of lipids that were reinforced by differences on some FA ratios expressing the activity coefficient of enzymes implicated on the FA pathway flux. (C) 2009 Elsevier Inc. All rights reserved.
Resumo:
Increased plasma levels of free fatty acids (FFA) occur in states of insulin resistance such as obesity and type 2 diabetes mellitus. These high levels of plasma FFA are proposed to play an important role for the development of insulin resistance but the mechanisms involved are still unclear. This study investigated the effects of saturated and unsaturated FFA on insulin sensitivity in parallel with mitochondrial function. C2C12 myotubes were treated for 24 h with 0.1 mM of saturated (palmitic and stearic) and unsaturated (oleic, linoleic, eicosapentaenoic, and docosahexaenoic) FFA. After this period, basal and insulin-stimulated glucose metabolism and mitochondrial function were evaluated. Saturated palmitic and stearic acids decreased insulin-induced glycogen synthesis, glucose oxidation, and lactate production. Basal glucose oxidation was also reduced. Palmitic and stearic acids impaired mitochondrial function as demonstrated by decrease of both mitochondrial hyperpolarization and ATP generation. These FFA also decreased Akt activation by insulin. As opposed to saturated FFA, unsaturated FFA did not impair glucose metabolism and mitochondrial function. Primary cultures of rat skeletal muscle cells exhibited similar responses to saturated FFA as compared to C2C12 cells. These results show that in muscle cells saturated FFA-induced mitochondrial dysfunction associated with impaired insulin-induced glucose metabolism. J. Cell. Physiol. 222: 187-194, 2010. (C) 2009 Wiley-Liss, Inc.
Resumo:
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.
Resumo:
Purkinje cell degeneration (pcd) mice have a mutation within the gene encoding cytosolic carboxypeptidase 1 (CCP1/Nna1), which has homology to metallocarboxypeptidases. To assess the function of CCP1/Nna1, quantitative proteomics and peptidomics approaches were used to compare proteins and peptides in mutant and wild-type mice. Hundreds of peptides derived from cytosolic and mitochondrial proteins are greatly elevated in pcd mouse hypothalamus, amygdala, cortex, prefrontal cortex, and striatum. However, the major proteins detected on 2-D gel electrophoresis were present in mutant and wild-type mouse cortex and hypothalamus at comparable levels, and proteasome activity is normal in these brain regions of pcd mice, suggesting that the increase in cellular peptide levels in the pcd mice is due to reduced degradation of the peptides downstream of the proteasome. Both nondegenerating and degenerating regions of pcd mouse brain, but not wild-type mouse brain, show elevated autophagy, which can be triggered by a decrease in amino acid levels. Taken together with previous studies on CCP1/Nna1, these data suggest that CCP1/Nna1 plays a role in protein turnover by cleaving proteasome-generated peptides into amino acids and that decreased peptide turnover in the pcd mice leads to cell death.-Berezniuk, I., Sironi, J., Callaway, M. B., Castro, L. M., Hirata, I. Y., Ferro, E. S., Fricker, L. D. CCP1/Nna1 functions in protein turnover in mouse brain: Implications for cell death in Purkinje cell degeneration mice. FASEB J. 24, 1813-1823 (2010). www.fasebj.org
Resumo:
Purpose: The aim of this study was investigate the association between complement Factor H polymorphism (Y402H) and age-related macular degeneration (AMD) in Brazilian patients. Methods: Patients with AMD aged 50 or more and age-matched healthy controls were enrolled in the study. Genomic DNA was isolated from leucocytes of patients and controls; the Y402H polymorphism of complement Factor H gene (CFH) was determined by polymerase chain reaction directed sequencing. Results: The frequency of 1277C allele of Factor H was 56.30% in patients with AMD compared with 36.51% in controls (p-value = 0.001). The genotypic distribution differed significantly between the two groups (1277CC 36.98%, 1277CT 38.65% and 1277TT 24.37% for AMD group; 1277CC 13.16%, 1277CT 46.71% and 1277TT 40.13% for controls, p-value = 0.001). The odds ratio for patients with AMD carrying only one 1277C allele was 1.36 and for those carrying two 1277C alleles was 4.63, when compared to the control group. Conclusions: These results suggest the Y402H polymorphism of CFH is a risk factor to the development of AMD in Brazilian patients. This is in accordance with findings from the majority of previous study population in Europe and North American.
Resumo:
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.
Resumo:
Steatosis is diagnosed on the basis of the macroscopic aspect of the liver evaluated by the surgeon at the time of organ extraction or by means of a frozen biopsy. In the present study, the applicability of laser-induced fluorescence (LIF) spectroscopy was investigated as a method for the diagnosis of different degrees of steatosis experimentally induced in rats. Rats received a high-lipid diet for different periods of time. The animals were divided into groups according to the degree of induced steatosis diagnosis by histology. The concentration of fat in the liver was correlated with LIF by means of the steatosis fluorescence factor (SFF). The histology classification, according to liver fat concentration was, Severe Steatosis, Moderate Steatosis, Mild Steatosis and Control (no liver steatosis). Fluorescence intensity could be directly correlated with fat content. It was possible to estimate an average of fluorescence intensity variable by means of different confidence intervals (P=95%) for each steatosis group. SFF was significantly higher in the Severe Steatosis group (P < 0.001) compared with the Moderate Steatosis, Mild Steatosis and Control groups. The various degrees of steatosis could be directly correlated with SFF. LIF spectroscopy proved to be a method capable of identifying the degree of hepatic steatosis in this animal model, and has the potential of clinical application for non-invasive evaluation of the degree of steatosis.
Resumo:
Four species of marine benthic algae (Laurencia filiformis, L. intricata, Gracilaria domingensis and G. birdiae) that belong to the phylum Rhodophyta were collected in Espirito Santo State, Brazil and investigated concerning their biochemical composition (fatty acid, total lipid, soluble proteins, amino acid and ash). The total content of lipid (% dry weight) ranged from 1.1% to 6.2%: fatty acid from 0.7% to 1.0%: soluble protein from 4.6% to 18.3%, amino acid from 6.7% to 11.3% and ash from 22.5% to 38.4%. judging from their composition, the four species of algae appear to be potential sources of dietary proteins, amino acids, lipids and essential fatty acids for humans and animals. (C) 2009 Elsevier Ltd. All rights reserved.
Resumo:
An alternative method for determination of total trans fatty acids expressed as elaidic acid by capillary zone electrophoresis (CZE) under indirect UV detection at 224 nm within an analysis time of 7.5 min was developed. The optimized running electrolyte includes 15.0 mmol L(-1) KH(2)PO(4)/Na(2)HPO(4) buffer (pH similar to 7.0), 4.0 mmol L(-1) SDBS, 8.0 mmol L(-1) Brij35, 45%v/v ACN, 8% methanol, and 1.5% v/v n-octanol. Baseline separation of the critical pair C18-9cis/C18:1-9t: with a resolution higher than 1.5 was achieved using C15:0 as the internal standard. The optimum capillary electrophoresis (CE) conditions for the background electrolyte were established with the aid of Raman spectroscopy and experiments of a 3(2) factorial design. After response factor (R(F)) calculations, the CE method was applied to total trans fatty acid (TTFA) analysis in a hydrogenated vegetable fat (HVF) sample, and compared with the American Oil Chemists` Society (AOCS) official method by gas chromatography (GC). The methods were compared with an independent sample t test, and no significant difference was found between CE and GC methods within the 95% confidence interval for six genuine replicates of TTFA analysis (p-value > 0.05). The CE method was applied to TTFA analysis in a spreadable cheese sample. Satisfactory results were obtained, indicating that the optimized methodology can be used for trans fatty acid determination for these samples.