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1.
Nat Commun ; 11(1): 4865, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978396

RESUMO

The metabolic state of an organism instructs gene expression modalities, leading to changes in complex life history traits, such as longevity. Dietary restriction (DR), which positively affects health and life span across species, leads to metabolic reprogramming that enhances utilisation of fatty acids for energy generation. One direct consequence of this metabolic shift is the upregulation of cytoprotective (CyTP) genes categorized in the Gene Ontology (GO) term of "Xenobiotic Detoxification Program" (XDP). How an organism senses metabolic changes during nutritional stress to alter gene expression programs is less known. Here, using a genetic model of DR, we show that the levels of polyunsaturated fatty acids (PUFAs), especially linoleic acid (LA) and eicosapentaenoic acid (EPA), are increased following DR and these PUFAs are able to activate the CyTP genes. This activation of CyTP genes is mediated by the conserved p38 mitogen-activated protein kinase (p38-MAPK) pathway. Consequently, genes of the PUFA biosynthesis and p38-MAPK pathway are required for multiple paradigms of DR-mediated longevity, suggesting conservation of mechanism. Thus, our study shows that PUFAs and p38-MAPK pathway function downstream of DR to help communicate the metabolic state of an organism to regulate expression of CyTP genes, ensuring extended life span.


Assuntos
Ácidos Graxos Insaturados/genética , Ácidos Graxos Insaturados/metabolismo , Regulação da Expressão Gênica , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Fenômenos Bioquímicos , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Ácido Eicosapentaenoico/análogos & derivados , Regulação da Expressão Gênica/genética , Técnicas de Silenciamento de Genes , Ácido Linoleico/metabolismo , Longevidade , Redes e Vias Metabólicas/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo
2.
Adv Gerontol ; 33(2): 265-272, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32593240

RESUMO

A decrease in cognitive functions up to the development of dementia in the elderly is associated with a decrease in the blood level of polyunsaturated fatty acids, especially Omega-3, which occurs against the background of oxidative stress. The paper presents a comparative analysis of the spectrum of polyunsaturated fatty acids and the activity of individual components of the enzymatic antioxidant system in the blood of elderly people with impaired cognitive performance to the level of «mild cognitive decline¼ (MCI AD, prodromal Alzheimer's disease) or vascular etiology (MCI VaD, prodromal vascular dementia) compared with older people without signs of cognitive impairment. A decrease in the concentration of Omega-3 polyunsaturated fatty acids in the blood of both groups of the examined patients was revealed compared with the control group. In patients with AD MCI, a sharp decrease in the concentration of arachidonic acid (Omega-6) was detected compared with patients with MCI VaD and the control group. The decrease in the activity of the antioxidant enzymatic system and the decrease in polyunsaturated fatty acids due to their peroxidation revealed in this study indicate an intensification of the OS processes in patients with impaired cognitive functions. The question of the pathogenetic role of arachidonic acid in patients predisposed in the future to the development of AD is discussed.


Assuntos
Doença de Alzheimer , Demência Vascular , Ácidos Graxos Insaturados/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Disfunção Cognitiva/metabolismo , Demência Vascular/metabolismo , Humanos
3.
Am J Clin Nutr ; 112(1): 13-18, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32491173

RESUMO

Based on decades of research, there is strong evidence that supports ongoing dietary recommendations to decrease intakes of SFAs and, more recently, to replace SFAs with unsaturated fat, including PUFAs and MUFAs. Epidemiologic research has shown that replacement of SFAs with unsaturated fat, but not refined carbohydrate and added sugars, is associated with a reduction in coronary heart disease events and death. There is much evidence from controlled clinical studies demonstrating that SFAs increase LDL cholesterol, a major causal factor in the development of cardiovascular disease. When each (nonprotein) dietary macronutrient isocalorically replaces SFA, the greatest LDL-cholesterol-lowering effect is seen with PUFA, followed by MUFA, and then total carbohydrate. New research on full-fat dairy products high in saturated fat, particularly fermented dairy foods, demonstrates some benefits for cardiometabolic diseases. However, compared with food sources of unsaturated fats, full-fat dairy products increase LDL cholesterol. Thus, current dietary recommendations to decrease SFA and replace it with unsaturated fat should continue to the basis for healthy food-based dietary patterns.


Assuntos
Gorduras na Dieta/metabolismo , Ácidos Graxos/metabolismo , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/prevenção & controle , LDL-Colesterol/metabolismo , Ácidos Graxos/análise , Ácidos Graxos Insaturados/análise , Ácidos Graxos Insaturados/metabolismo , História do Século XXI , Humanos , Saúde Pública/história , Saúde Pública/normas , Ensaios Clínicos Controlados Aleatórios como Assunto , Recomendações Nutricionais/história
4.
PLoS One ; 15(5): e0233322, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32469895

RESUMO

The importance of dietary lipids in male reproduction are not as well understood as in females, in which dietary lipids, such as phospholipids (PL) and associated fatty acids (FA), are important structural components of the eggs and provide energy for their offspring. In mammals, lipids are suggested to be important for spermatogenesis and to structural components of the spermatozoa that could improve fertilization rates. New knowledge of how lipids affect sexual maturation in male Atlantic salmon (Salmo salar), an important global aquaculture species, could provide tools to delay maturation and/or improve reproductive success. Therefore, changes in testicular composition of lipids and gene transcripts associated with spermatogenesis and lipid metabolism were studied in sexually maturing male salmon compared to immature males and females. An increase in total testis content of FA and PL, and a shift to higher PL composition was observed in maturing males, concomitant with increases in mRNA levels for genes involved in spermatogenesis, FA uptake and synthesis, and production of long chain-polyunsaturated fatty acids (LC-PUFA) and PL. A particularly interesting finding was elevated testis expression of acyl-CoA synthetase 4 (acsl4), and acyl-CoA thioesterase 2 (acot2), critical enzymes that regulate intra-mitochondrial levels of 20:4n-6 FA (arachidonic acid), which have been associated with improved cholesterol transport during steroidogenesis. This suggested that FA may have direct effects on sex steroid production in salmon. Furthermore, we observed increased testis expression of genes for endogenous synthesis of 16:0 and elongation/desaturation to 22:6n-3 (docosahexaenoic acid) in sexually maturing males relative to immature fish. Both of these FA are important structural components of the PL, phosphatidylcholine (PC), and were elevated concomitant with increases in the content of phosphatidic acid, an important precursor for PC, in maturing males compared to immature fish. Overall, this study suggests that, similar to mammals, lipids are important to spermatogenesis and serve as structural components during testicular growth and maturation in Atlantic salmon.


Assuntos
Ácidos Graxos Insaturados/metabolismo , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica , Fosfolipídeos/metabolismo , Salmo salar/metabolismo , Maturidade Sexual , Testículo/metabolismo , Animais , Ácidos Graxos Dessaturases/genética , Feminino , Proteínas de Peixes/genética , Perfilação da Expressão Gênica , Masculino , Salmo salar/genética , Testículo/citologia
5.
Nat Commun ; 11(1): 2258, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32382158

RESUMO

En route to a bio-based chemical industry, the conversion of fatty acids into building blocks is of particular interest. Enzymatic routes, occurring under mild conditions and excelling by intrinsic selectivity, are particularly attractive. Here we report photoenzymatic cascade reactions to transform unsaturated fatty acids into enantiomerically pure secondary fatty alcohols. In a first step the C=C-double bond is stereoselectively hydrated using oleate hydratases from Lactobacillus reuteri or Stenotrophomonas maltophilia. Also, dihydroxylation mediated by the 5,8-diol synthase from Aspergillus nidulans is demonstrated. The second step comprises decarboxylation of the intermediate hydroxy acids by the photoactivated decarboxylase from Chlorella variabilis NC64A. A broad range of (poly)unsaturated fatty acids can be transformed into enantiomerically pure fatty alcohols in a simple one-pot approach.


Assuntos
Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/metabolismo , Álcoois Graxos/química , Álcoois Graxos/metabolismo , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Lactobacillus reuteri/metabolismo , Stenotrophomonas maltophilia/metabolismo , Especificidade por Substrato
6.
Toxicol Appl Pharmacol ; 398: 115034, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32387183

RESUMO

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a potent aryl hydrocarbon receptor (AhR) agonist that elicits a broad spectrum of dose-dependent hepatic effects including lipid accumulation, inflammation, and fibrosis. To determine the role of inflammatory lipid mediators in TCDD-mediated hepatotoxicity, eicosanoid metabolism was investigated. Female Sprague-Dawley (SD) rats were orally gavaged with sesame oil vehicle or 0.01-10 µg/kg TCDD every 4 days for 28 days. Hepatic RNA-Seq data was integrated with untargeted metabolomics of liver, serum, and urine, revealing dose-dependent changes in linoleic acid (LA) and arachidonic acid (AA) metabolism. TCDD also elicited dose-dependent differential gene expression associated with the cyclooxygenase, lipoxygenase, and cytochrome P450 epoxidation/hydroxylation pathways with corresponding changes in ω-6 (e.g. AA and LA) and ω-3 polyunsaturated fatty acids (PUFAs), as well as associated eicosanoid metabolites. Overall, TCDD increased the ratio of ω-6 to ω-3 PUFAs. Phospholipase A2 (Pla2g12a) was induced consistent with increased AA metabolism, while AA utilization by induced lipoxygenases Alox5 and Alox15 increased leukotrienes (LTs). More specifically, TCDD increased pro-inflammatory eicosanoids including leukotriene LTB4, and LTB3, known to recruit neutrophils to damaged tissue. Dose-response modeling suggests the cytochrome P450 hydroxylase/epoxygenase and lipoxygenase pathways are more sensitive to TCDD than the cyclooxygenase pathway. Hepatic AhR ChIP-Seq analysis found little enrichment within the regulatory regions of differentially expressed genes (DEGs) involved in eicosanoid biosynthesis, suggesting TCDD-elicited dysregulation of eicosanoid metabolism is a downstream effect of AhR activation. Overall, these results suggest alterations in eicosanoid metabolism may play a key role in TCDD-elicited hepatotoxicity associated with the progression of steatosis to steatohepatitis.


Assuntos
Eicosanoides/metabolismo , Ácidos Graxos Insaturados/metabolismo , Fígado/efeitos dos fármacos , Dibenzodioxinas Policloradas/farmacologia , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Ácidos Graxos Ômega-3/metabolismo , Fígado Gorduroso/metabolismo , Feminino , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Hidrocarboneto Arílico/metabolismo
7.
Adv Exp Med Biol ; 1260: 33-83, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32304030

RESUMO

Our own studies and those of others have shown that defects in essential fatty acid (EFA) metabolism occurs in age-related disorders such as obesity, type 2 diabetes mellitus, hypertension, atherosclerosis, coronary heart disease, immune dysfunction and cancer. It has been noted that in all these disorders there could occur a defect in the activities of desaturases, cyclo-oxygenase (COX), and lipoxygenase (LOX) enzymes leading to a decrease in the formation of their long-chain products gamma-linolenic acid (GLA), arachidonic acid, eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA). This leads to an increase in the production of pro-inflammatory prostaglandin E2 (PGE2), thromboxanes (TXs), and leukotrienes (LTs) and a decrease in anti-inflammatory lipoxin A4, resolvins, protectins and maresins. All these bioactive molecules are termed as bioactive lipids (BALs). This imbalance in the metabolites of EFAs leads to low-grade systemic inflammation and at times acute inflammatory events at specific local sites that trigger the development of various age-related disorders such as obesity, type 2 diabetes mellitus, hypertension, coronary heart disease, atherosclerosis, and immune dysfunction as seen in rheumatoid arthritis, lupus, nephritis and other localized inflammatory conditions. This evidence implies that methods designed to restore BALs to normal can prevent age-related disorders and enhance longevity and health.


Assuntos
Envelhecimento/metabolismo , Envelhecimento/patologia , Doença , Ácidos Graxos Essenciais/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Graxos Insaturados/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/patologia
8.
PLoS One ; 15(4): e0231223, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32298286

RESUMO

We observed prominent effects of doxorubicin (Dox), an anthracycline widely used in anti-cancer therapy, on the aggregation and intracellular distribution of both partners of the H2A-H2B dimer, with marked differences between the two histones. Histone aggregation, assessed by Laser Scanning Cytometry via the retention of the aggregates in isolated nuclei, was observed in the case of H2A. The dominant effect of the anthracycline on H2B was its massive accumulation in the cytoplasm of the Jurkat leukemia cells concomitant with its disappearance from the nuclei, detected by confocal microscopy and mass spectrometry. A similar effect of the anthracycline was observed in primary human lymphoid cells, and also in monocyte-derived dendritic cells that harbor an unusually high amount of H2B in their cytoplasm even in the absence of Dox treatment. The nucleo-cytoplasmic translocation of H2B was not affected by inhibitors of major biochemical pathways or the nuclear export inhibitor leptomycin B, but it was completely diminished by PYR-41, an inhibitor with pleiotropic effects on protein degradation pathways. Dox and PYR-41 acted synergistically according to isobologram analyses of cytotoxicity. These large-scale effects were detected already at Dox concentrations that may be reached in the typical clinical settings, therefore they can contribute both to the anti-cancer mechanism and to the side-effects of this anthracycline.


Assuntos
Citoplasma/metabolismo , Doxorrubicina/farmacologia , Histonas/metabolismo , Transporte Ativo do Núcleo Celular , Antraciclinas/farmacologia , Antineoplásicos/farmacologia , Núcleo Celular/metabolismo , Proliferação de Células , Ácidos Graxos Insaturados/metabolismo , Humanos , Células Jurkat , Citometria de Varredura a Laser , Espectrometria de Massas , Microscopia Confocal , Monócitos/citologia
9.
Nat Commun ; 11(1): 1775, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286299

RESUMO

The increased incidence of inflammatory bowel disease (IBD) has become a global phenomenon that could be related to adoption of a Western life-style. Westernization of dietary habits is partly characterized by enrichment with the ω-6 polyunsaturated fatty acid (PUFA) arachidonic acid (AA), which entails risk for developing IBD. Glutathione peroxidase 4 (GPX4) protects against lipid peroxidation (LPO) and cell death termed ferroptosis. We report that small intestinal epithelial cells (IECs) in Crohn's disease (CD) exhibit impaired GPX4 activity and signs of LPO. PUFAs and specifically AA trigger a cytokine response of IECs which is restricted by GPX4. While GPX4 does not control AA metabolism, cytokine production is governed by similar mechanisms as ferroptosis. A PUFA-enriched Western diet triggers focal granuloma-like neutrophilic enteritis in mice that lack one allele of Gpx4 in IECs. Our study identifies dietary PUFAs as a trigger of GPX4-restricted mucosal inflammation phenocopying aspects of human CD.


Assuntos
Doença de Crohn/metabolismo , Gorduras na Dieta/efeitos adversos , Enterite/metabolismo , Ácidos Graxos Insaturados/metabolismo , Inflamação/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Adulto , Animais , Morte Celular/genética , Morte Celular/fisiologia , Doença de Crohn/genética , Enterite/etiologia , Enterite/genética , Ácidos Graxos Insaturados/genética , Feminino , Glutationa Peroxidase/metabolismo , Humanos , Inflamação/genética , Peroxidação de Lipídeos/genética , Peroxidação de Lipídeos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética
10.
Gene ; 741: 144559, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32169630

RESUMO

The fungi in order Mortierellales are attractive producers for long-chain polyunsaturated fatty acids (PUFAs). Here, the genome sequencing and assembly of a novel strain of Mortierella sp. BCC40632 were done, yielding 65 contigs spanning of 49,964,116 total bases with predicted 12,149 protein-coding genes. We focused on the acetyl-CoA in relevant to its derived metabolic pathways for biosynthesis of macromolecules with biological functions, including PUFAs, eicosanoids and carotenoids. By comparative genome analysis between Mortierellales and Mucorales, the signature genetic characteristics of the arachidonic acid-producing strains, including Δ5-desaturase and GLELO-like elongase, were also identified in the strain BCC40632. Remarkably, this fungal strain contained only n-6 pathway of PUFA biosynthesis due to the absence of Δ15-desaturase or ω3-desaturase gene in contrast to other Mortierella species. Four putative enzyme sequences in the eicosanoid biosynthetic pathways were identified in the strain BCC40632 and others Mortierellale fungi, but were not detected in the Mucorales. Another unique metabolic trait of the Mortierellales was the inability in carotenoid synthesis as a result of the lack of phytoene synthase and phytoene desaturase genes. The findings provide a perspective in strain optimization for production of tailored-made products with industrial applications.


Assuntos
Acetilcoenzima A/biossíntese , Ácido Araquidônico/genética , Genoma Fúngico/genética , Mortierella/metabolismo , Acetilcoenzima A/genética , Ácido Araquidônico/biossíntese , Vias Biossintéticas/genética , Ácidos Graxos Dessaturases/genética , Elongases de Ácidos Graxos/genética , Ácidos Graxos Insaturados/genética , Ácidos Graxos Insaturados/metabolismo , Mortierella/genética , Mucorales/genética , Mucorales/metabolismo , Ácido gama-Linolênico/genética , Ácido gama-Linolênico/metabolismo
11.
Nat Commun ; 11(1): 1496, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32198415

RESUMO

The ability to grow at moderate acidic conditions (pH 4.0-5.0) is important to Escherichia coli colonization of the host's intestine. Several regulatory systems are known to control acid resistance in E. coli, enabling the bacteria to survive under acidic conditions without growth. Here, we characterize an acid-tolerance response (ATR) system and its regulatory circuit, required for E. coli exponential growth at pH 4.2. A two-component system CpxRA directly senses acidification through protonation of CpxA periplasmic histidine residues, and upregulates the fabA and fabB genes, leading to increased production of unsaturated fatty acids. Changes in lipid composition decrease membrane fluidity, F0F1-ATPase activity, and improve intracellular pH homeostasis. The ATR system is important for E. coli survival in the mouse intestine and for production of higher level of 3-hydroxypropionate during fermentation. Furthermore, this ATR system appears to be conserved in other Gram-negative bacteria.


Assuntos
Tolerância a Medicamentos/fisiologia , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/genética , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Sequência de Bases , Sítios de Ligação , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Ácido Graxo Sintase Tipo II/genética , Ácido Graxo Sintase Tipo II/metabolismo , Ácidos Graxos Insaturados/metabolismo , Feminino , Fermentação , Regulação Bacteriana da Expressão Gênica , Homeostase , Hidroliases/genética , Hidroliases/metabolismo , Concentração de Íons de Hidrogênio , Intestinos/microbiologia , Ácido Láctico/análogos & derivados , Ácido Láctico/metabolismo , Fluidez de Membrana , Lipídeos de Membrana , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Quinases/metabolismo , Transcrição Genética
12.
Arch Med Res ; 51(2): 105-114, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32111491

RESUMO

Resveratrol modulates the transcription factor NF-κB, cytochrome P450 isoenzyme CYP1A1, expression and activity of cyclooxygenase (COX) enzymes, Fas/Fas ligand mediated apoptosis, p53, mTOR and cyclins and various phospho-diesterases resulting in an increase in cytosolic cAMP levels. Cyclic AMP, in turn, activates Epac1/CaMKKß/AMPK/SIRT1/PGC-1α pathway that facilitates increased oxidation of fatty acids, mitochondrial respiration and their biogenesis and gluconeogenesis. Resveratrol triggers apoptosis of activated T cells and suppresses tumor necrosis factor-α (TNF-α), interleukin-17 (IL-17) and other pro-inflammatory molecules and inhibits expression of hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) that may explain its anti-inflammatory actions. Polyunsaturated fatty acids (PUFAs) and their anti-inflammatory metabolites lipoxin A4, resolvins, protectins and maresins have a significant role in obesity, type 2 diabetes mellitus (T2DM), metabolic syndrome and cancer. We observed that PUFAs (especially arachidonic acid, AA) and BDNF (brain-derived neurotrophic factor) protect against the cytotoxic actions of alloxan, streptozotocin, benzo(a)pyrene (BP) and doxorubicin. Thus, there is an overlap in the beneficial actions of resveratrol, PUFAs and BDNF suggesting that these molecules may interact and augment synthesis and action of each other. This is supported by the observation that resveratrol and PUFAs modulate gut microbiota and influence stem cell proliferation and differentiation. Since resveratrol is not easily absorbed from the gut it is likely that it may act on endocannabinoid and light, odor, and taste receptors located in the gut, which, in turn, convey their messages to the various organs via vagus nerve.


Assuntos
Antioxidantes/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Ácidos Graxos Insaturados/metabolismo , Resveratrol/uso terapêutico , Antioxidantes/farmacologia , Humanos , Resveratrol/farmacologia
13.
Proc Natl Acad Sci U S A ; 117(11): 5923-5930, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32123095

RESUMO

Arachidonic acid epoxides generated by cytochrome P450 (CYP) enzymes have been linked to increased tumor growth and metastasis, largely on the basis of overexpression studies and the application of exogenous epoxides. Here we studied tumor growth and metastasis in Cyp2c44-/- mice crossed onto the polyoma middle T oncogene (PyMT) background. The resulting PyMT2c44 mice developed more primary tumors earlier than PyMT mice, with increased lymph and lung metastasis. Primary tumors from Cyp2c44-deficient mice contained higher numbers of tumor-associated macrophages, as well as more lymphatic endothelial cells than tumors from PyMT mice. While epoxide and diol levels were comparable in tumors from both genotypes, prostaglandin (PG) levels were higher in the PyMTΔ2c44 tumors. This could be accounted for by the finding that Cyp2c44 metabolized the PG precursor, PGH2 to 12(S)-hydroxyheptadeca-5Z,8E,10E-trienoic acid (12-HHT), thus effectively reducing levels of effector PGs (including PGE2). Next, proteomic analyses revealed an up-regulation of WD repeating domain FYVE1 (WDFY1) in tumors from PyMTΔ2c44 mice, a phenomenon that was reproduced in Cyp2c44-deficient macrophages as well as by PGE2 Mechanistically, WDFY1 was involved in Toll-like receptor signaling, and its down-regulation in human monocytes attenuated the LPS-induced phosphorylation of IFN regulatory factor 3 and nuclear factor-κB. Taken together, our results indicate that Cyp2c44 protects against tumor growth and metastasis by preventing the synthesis of PGE2 The latter eicosanoid influenced macrophages at least in part by enhancing Toll-like receptor signaling via the up-regulation of WDFY1.


Assuntos
Neoplasias da Mama/metabolismo , Família 2 do Citocromo P450/metabolismo , Linfangiogênese/fisiologia , Prostaglandinas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Família 2 do Citocromo P450/genética , Modelos Animais de Doenças , Células Endoteliais/patologia , Ácidos Graxos Insaturados/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Linfangiogênese/genética , Macrófagos , Camundongos , Camundongos Knockout , Monócitos , Processos Neoplásicos , Proteômica , Transdução de Sinais , Receptores Toll-Like , Regulação para Cima
14.
J Breath Res ; 14(3): 034001, 2020 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-32163929

RESUMO

The assessment of volatile compounds (VOCs) for disease diagnosis is a growing area of research. There is a need to provide hard evidence i.e. biochemical routes, to justify putative VOC biomarkers, as in many cases this remains uncertain, which weakens their authenticity. Recently reports of volatile hydrocarbons and or aldehydes in bodily fluids and breath have been attributed to oxidative stress, although as discussed here, fewer compounds have been reported than expected from a mechanistic examination. Oxidative stress can result from many disease states which produce inflammation, and a better understanding of the interconnection between oxidative stress and the release of VOCs from target diseased and healthy organs could greatly help diagnoses. It is generally considered that oxidation of unsaturated fatty acids are a major source of these VOCs. An investigation listing the many possible volatile oxidation products has not been undertaken. This is described here using a mechanistic analysis (based on the literature) of the compounds derived from molecular cleavage and the results compared with a recent review of all the VOCs emanating from the human body, which satisfactorily explains the presence of at least 100 VOCs. Six important unsaturated fatty acids, oleic, palmitoleic, linoleic, linolenic, arachidonic, and cervonic acids have been shown to be capable of producing up to 18 n+6 unique breakdown products (where n = the number of alkene double bonds in the fatty acid hydrocarbon chain), in total 299 compounds. In many cases these have not been reported. We suggest several reasons for this: these VOCs have not been expected, so researchers are not looking for them and importantly some are not present in the mass spectral libraries, or they are too low a concentration to have been detected, or are not present. Furthermore a theoretical explanation for the origins of branched aldehydes and other compounds arising from bacterial oxidative metabolism of unsaturated fatty acids are described.


Assuntos
Ácidos Graxos Insaturados/metabolismo , Corpo Humano , Peroxidação de Lipídeos , Compostos Orgânicos Voláteis/análise , Testes Respiratórios/métodos , Ácidos Graxos Insaturados/química , Humanos , Oxirredução
15.
Biochemistry (Mosc) ; 85(Suppl 1): S34-S55, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32087053

RESUMO

This review discusses formation of reactive halogen species (RHS) catalyzed by myeloperoxidase (MPO), an enzyme mostly present in leukocytes. An imbalance between the RHS production and body's ability to remove or neutralize them leads to the development of halogenative stress. RHS reactions with proteins, lipids, carbohydrates, and antioxidants in the content of low-density lipoproteins (LDLs) of the human blood are described. MPO binds site-specifically to the LDL surface and modifies LDL properties and structural organization, which leads to the LDL conversion into proatherogenic forms captured by monocytes/macrophages, which causes accumulation of cholesterol and its esters in these cells and their transformation into foam cells, the basis of atherosclerotic plaques. The review describes the biomarkers of MPO enzymatic activity and halogenative stress, as well as the involvement of the latter in the development of atherosclerosis.


Assuntos
Aterosclerose/metabolismo , Halogenação , Halogênios/metabolismo , Lipoproteínas LDL/metabolismo , Placa Aterosclerótica/metabolismo , Sítios de Ligação , Biomarcadores/metabolismo , Colesterol/metabolismo , Ácidos Graxos Insaturados/metabolismo , Células Espumosas/metabolismo , Radicais Livres/metabolismo , Humanos , Ácido Hipocloroso/metabolismo , Leucócitos/metabolismo , Peroxidase/metabolismo
16.
PLoS One ; 15(2): e0226123, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32032370

RESUMO

The visual photopigment protein rhodopsin (Rh) is a typical G protein-coupled receptor (GPCR) that initiates the phototransduction cascade in retinal disk membrane of rod-photoreceptor cells. Rh molecule has a tendency to form dimer, and the dimer tends to form rows, which is suggested to heighten phototransduction efficiency in single-photon regime. In addition, the dimerization confers Rh an affinity for lipid raft, i.e. raftophilicity. However, the mechanism by which Rh-dimer raftophilicity contributes to the organization of the higher order structure remains unknown. In this study, we performed coarse-grained molecular dynamics simulations of a disk membrane model containing unsaturated lipids, saturated lipids with cholesterol, and Rh-dimers. We described the Rh-dimers by two-dimensional particle populations where the palmitoyl moieties of each Rh exhibits raftophilicity. We simulated the structuring of Rh in a disk for two types of Rh-dimer, i.e., the most and second most stable Rh dimers, which exposes the raftophilic regions at the dimerization-interface (H1/H8 dimer) and two edges away from the interface (H4/H5 dimer), respectively. Our simulations revealed that only the H1/H8 dimer could form a row structure. A small number of raftophilic lipids recruited to and intercalated in a narrow space between H1/H8 dimers stabilize the side-by-side interaction between dimers in a row. Our results implicate that the nano-sized lipid raft domains act as a "glue" to organize the long row structures of Rh-dimers.


Assuntos
Simulação de Dinâmica Molecular , Multimerização Proteica , Rodopsina/química , Rodopsina/metabolismo , Colesterol/metabolismo , Cristalografia por Raios X , Ácidos Graxos Insaturados/metabolismo , Cinética , Bicamadas Lipídicas/metabolismo , Lipoilação , Microdomínios da Membrana/metabolismo , Membranas/química , Membranas/metabolismo , Modelos Moleculares , Conformação Proteica em alfa-Hélice , Células Fotorreceptoras Retinianas Bastonetes/metabolismo
17.
Am J Clin Nutr ; 111(4): 739-748, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32020168

RESUMO

BACKGROUND: Modifying dairy fat composition by increasing the MUFA content is a potential strategy to reduce dietary SFA intake for cardiovascular disease (CVD) prevention in the population. OBJECTIVES: To determine the effects of consuming SFA-reduced, MUFA-enriched (modified) dairy products, compared with conventional dairy products (control), on the fasting cholesterol profile (primary outcome), endothelial function assessed by flow-mediated dilatation (FMD; key secondary outcome), and other cardiometabolic risk markers. METHODS: A double-blind, randomized, controlled crossover 12-wk intervention was conducted. Participants with a 1.5-fold higher (moderate) CVD risk than the population mean replaced habitual dairy products with study products (milk, cheese, and butter) to achieve a high-fat, high-dairy isoenergetic daily dietary exchange [38% of total energy intake (%TE) from fat: control (dietary target: 19%TE SFA; 11%TE MUFA) and modified (16%TE SFA; 14%TE MUFA) diet]. RESULTS: Fifty-four participants (57.4% men; mean ± SEM age: 52 ± 3 y; BMI: 25.8 ± 0.5 kg/m2) completed the study. The modified diet attenuated the rise in fasting LDL cholesterol observed with the control diet (0.03 ± 0.06 mmol/L and 0.19 ± 0.05 mmol/L, respectively; P = 0.03). Relative to baseline, the %FMD response increased after the modified diet (0.35% ± 0.15%), whereas a decrease was observed after the control diet (-0.51% ± 0.15%; P< 0.0001). In addition, fasting plasma nitrite concentrations increased after the modified diet, yet decreased after the control diet (0.02 ± 0.01 µmol/L and -0.03 ± 0.02 µmol/L, respectively; P = 0.01). CONCLUSIONS: In adults at moderate CVD risk, consumption of a high-fat diet containing SFA-reduced, MUFA-enriched dairy products for 12 wk showed beneficial effects on fasting LDL cholesterol and endothelial function compared with conventional dairy products. Our findings indicate that fatty acid modification of dairy products may have potential as a public health strategy aimed at CVD risk reduction. This trial was registered at clinicaltrials.gov as NCT02089035.


Assuntos
Doenças Cardiovasculares/prevenção & controle , LDL-Colesterol/metabolismo , Gorduras Insaturadas/metabolismo , Ácidos Graxos Insaturados/metabolismo , Doenças Cardiovasculares/dietoterapia , Doenças Cardiovasculares/metabolismo , Gorduras na Dieta/metabolismo , Dilatação , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Artigo em Inglês | MEDLINE | ID: mdl-32058894

RESUMO

INTRODUCTION: Omega-3 DHA is important for the prevention of preterm birth, however there is limited knowledge of the determinants of omega-3 status during pregnancy. The primary objective of this systematic review was to synthesise data from existing studies assessing relationships between clinical factors and maternal DHA status. MATERIALS AND METHODS: The Medline, Embase, Amed, and CINAHL databases were searched for studies reporting measures of maternal omega-3 status and one or more clinical characteristics. RESULTS: Eighteen studies were included in the final analyses. Factors associated with a higher BMI (overweight, higher gestational weight gain, gestational diabetes), or lower parity were each associated with higher omega-3 status in the majority of studies, with mixed findings for other comparisons. DISCUSSION: Inconsistent findings between studies make it difficult to draw clear conclusions about the relationship between clinical factors and maternal omega-3 DHA status. However, maternal overweight and associated metabolic conditions may increase lipid metabolism.


Assuntos
Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Graxos Insaturados/metabolismo , Nascimento Prematuro/prevenção & controle , Índice de Massa Corporal , Feminino , Idade Gestacional , Humanos , Metabolismo dos Lipídeos , Gravidez , Resultado da Gravidez
19.
J Immunol Res ; 2020: 3813250, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32090128

RESUMO

The current study is aimed at highlighting the impact of enterally or parenterally applied immunoglobulins (Igs) on polyunsaturated fatty acid (PUFA) absorption in newborn pigs. Piglets were chosen as the appropriate model since they are born agammaglobulinemic and any effects of Ig addition can thus be easily monitored. Twenty-one, new born piglets were used in the study. Plasma levels of PUFAs, ARA, DHA, and EPA dropped (similarly to that seen in human infants) by between 40 and 50% in newborn, unsuckled piglets fed an infant formula for 48 h. However, piglets fed the same infant formula but supplied with immunoglobulins (Igs) either orally, by feeding piglets with swine or bovine colostrum, or intravenously, by i.u.a. (intraumbilical artery) infusion of swine or human Ig preparations or swine serum, demonstrated improved growth and PUFA levels similar to those observed at birth. The significant positive correlation was found between the body weight gain, as well as levels of ARA and EPA, and plasma immunoglobulins concentration. These results indicate the importance of the presence of Ig in the blood for appropriate absorption of dietary PUFAs and probably other nutrients in newborn piglets. This may have an impact on the dietary guidelines for human neonates, especially those born prematurely with low plasma Ig levels, since PUFAs are important factors for brain development in early life.


Assuntos
Ácidos Graxos Insaturados/metabolismo , Absorção Gastrointestinal , Imunoglobulina G/sangue , Período Pós-Parto , Animais , Animais Recém-Nascidos , Biomarcadores , Bovinos , Humanos , Suínos
20.
World J Microbiol Biotechnol ; 36(1): 17, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31912247

RESUMO

In this study, the effects of limited and excess nitrate on biomass, lipid production, and fatty acid profile in Messastrum gracile SE-MC4 were determined. The expression of fatty acid desaturase genes, namely stearoyl-ACP desaturase (SAD), omega-6 fatty acid desaturase (ω-6 FAD), omega-3 fatty acid desaturase isoform 1 (ω-3 FADi1), and omega-3 fatty acid desaturase isoform 2 (ω-3 FADi2) was also assessed. It was found that nitrate limitation generally increased the total oil, α-linolenic acid (C18:3n3) and total polyunsaturated fatty acid (PUFA) contents in M. gracile. The reduction of nitrate concentration from 1.76 to 0.11 mM increased the total oil content significantly from 32.5 to 41.85% (dry weight). Palmitic (C16:0) and oleic (C18:1) acids as the predominant fatty acids in this microalgae constituted between 82 and 87% of the total oil content and were relatively consistent throughout all nitrate concentrations tested. The expression of SAD, ω-6 FAD, and ω-3 FADi2 genes increased under nitrate limitation, especially at 0.11 mM nitrate. The ω-3 FADi1 demonstrated a binary up-regulation pattern of expression under both nitrate-deficient (0.11 mM) and -excess (3.55 mM) conditions. Thus, findings from this study suggested that limited or excess nitrate could be used as part of a cultivation strategy to increase oil and PUFA content following media optimisation and more efficient culture methodology. Data obtained from the expression of desaturase genes would provide valuable insights into their roles under excess and limited nitrate conditions in M. gracile, potentially paving the way for future genetic modifications.


Assuntos
Ácidos Graxos Dessaturases/genética , Ácidos Graxos/análise , Microalgas/crescimento & desenvolvimento , Nitrogênio/metabolismo , Biomassa , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Insaturados/metabolismo , Regulação Enzimológica da Expressão Gênica , Metabolismo dos Lipídeos , Microalgas/genética , Microalgas/metabolismo , Ácido Oleico/metabolismo , Ácido Palmítico/metabolismo , Ácido alfa-Linoleico/metabolismo
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