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1.
Proc Natl Acad Sci U S A ; 118(5)2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33495334

RESUMO

Seminal fluid plays an essential role in promoting male reproductive success and modulating female physiology and behavior. In the fruit fly, Drosophila melanogaster, Sex Peptide (SP) is the best-characterized protein mediator of these effects. It is secreted from the paired male accessory glands (AGs), which, like the mammalian prostate and seminal vesicles, generate most of the seminal fluid contents. After mating, SP binds to spermatozoa and is retained in the female sperm storage organs. It is gradually released by proteolytic cleavage and induces several long-term postmating responses, including increased ovulation, elevated feeding, and reduced receptivity to remating, primarily signaling through the SP receptor (SPR). Here, we demonstrate a previously unsuspected SPR-independent function for SP. We show that, in the AG lumen, SP and secreted proteins with membrane-binding anchors are carried on abundant, large neutral lipid-containing microcarriers, also found in other SP-expressing Drosophila species. These microcarriers are transferred to females during mating where they rapidly disassemble. Remarkably, SP is a key microcarrier assembly and disassembly factor. Its absence leads to major changes in the seminal proteome transferred to females upon mating. Males expressing nonfunctional SP mutant proteins that affect SP's binding to and release from sperm in females also do not produce normal microcarriers, suggesting that this male-specific defect contributes to the resulting widespread abnormalities in ejaculate function. Our data therefore reveal a role for SP in formation of seminal macromolecular assemblies, which may explain the presence of SP in Drosophila species that lack the signaling functions seen in Dmelanogaster.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Lipídeos/química , Microesferas , Sêmen/química , Animais , Proteínas de Drosophila/genética , Feminino , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Mutação/genética , Proteoma/metabolismo , Comportamento Sexual Animal , Especificidade da Espécie
2.
Semin Cell Dev Biol ; 108: 55-64, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32446655

RESUMO

Proper regulation of cellular lipid storage and oxidation is indispensable for the maintenance of cellular energy homeostasis and health. Mitochondrial function has been shown to be a main determinant of functional lipid storage and oxidation, which is of particular interest for the adipose tissue, as it is the main site of triacylglyceride storage in lipid droplets (LDs). Recent studies have identified a subpopulation of mitochondria attached to LDs, peridroplet mitochondria (PDM) that can be separated from cytoplasmic mitochondria (CM) by centrifugation. PDM have distinct bioenergetics, proteome, cristae organization and dynamics that support LD build-up, however their role in adipose tissue biology remains largely unexplored. Therefore, understanding the molecular basis of LD homeostasis and their relationship to mitochondrial function and attachment in adipocytes is of major importance.


Assuntos
Gotículas Lipídicas/metabolismo , Mitocôndrias/metabolismo , Tecido Adiposo/metabolismo , Animais , Sistema Endócrino/metabolismo , Humanos , Gotículas Lipídicas/ultraestrutura , Mitocôndrias/ultraestrutura , Terapia de Alvo Molecular
3.
Biochem J ; 478(10): 1861-1877, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33900381

RESUMO

Fatty acid transport protein 4 (FATP4) belongs to a family of acyl-CoA synthetases which activate long-chain fatty acids into acyl-CoAs subsequently used in specific metabolic pathways. Patients with FATP4 mutations and Fatp4-null mice show thick desquamating skin and other complications, however, FATP4 role on macrophage functions has not been studied. We here determined whether the levels of macrophage glycerophospholipids, sphingolipids including ceramides, triacylglycerides, and cytokine release could be altered by FATP4 inactivation. Two in vitro experimental systems were studied: FATP4 knockdown in THP-1-derived macrophages undergoing M1 (LPS + IFNγ) or M2 (IL-4) activation and bone marrow-derived macrophages (BMDMs) from macrophage-specific Fatp4-knockout (Fatp4M-/-) mice undergoing tunicamycin (TM)-induced endoplasmic reticulum stress. FATP4-deficient macrophages showed a metabolic shift towards triacylglycerides and were protected from M1- or TM-induced release of pro-inflammatory cytokines and cellular injury. Fatp4M-/- BMDMs showed specificity in attenuating TM-induced activation of inositol-requiring enzyme1α, but not other unfolded protein response pathways. Under basal conditions, FATP4/Fatp4 deficiency decreased the levels of ceramides and induced an up-regulation of mannose receptor CD206 expression. The deficiency led to an attenuation of IL-8 release in THP-1 cells as well as TNF-α and IL-12 release in BMDMs. Thus, FATP4 functions as an acyl-CoA synthetase in macrophages and its inactivation suppresses the release of pro-inflammatory cytokines by shifting fatty acids towards the synthesis of specific lipids.


Assuntos
Citocinas/metabolismo , Estresse do Retículo Endoplasmático , Proteínas de Transporte de Ácido Graxo/fisiologia , Macrófagos/imunologia , Triglicerídeos/metabolismo , Resposta a Proteínas não Dobradas , Acil Coenzima A/metabolismo , Animais , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Mieloides/metabolismo , Transdução de Sinais
4.
J Nutr ; 151(10): 2997-3035, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34510181

RESUMO

BACKGROUND: Palmitic acid (PA; 16:0) is added to infant formula in the form of palm oil/palm olein (PO/POL) and stereospecific numbered-2 palmitate (SN2). Several studies have examined the effects of PO/POL and or SN2 in formulas on health outcomes, mainly growth, digestion, and absorption of nutrients. However, the roles of PA, PO/POL, and SN2 on neurodevelopment remains unknown. OBJECTIVES: The objective of this scoping review was to map out studies in infants fed formula with PO/POL or SN2 to identify current knowledge on the role of PA in infant nutrition, specifically neurodevelopment. METHODS: Data sources, including Medline, Embase, CAB Abstracts, and the Cochrane Database, were searched. Eligible articles were randomized controlled trials (RCTs) and observational studies examining outcomes in term singleton infants fed formula containing PO/POL or SN2. Studies examining preterm infants or infants with infections, mixed-feeding interventions, or outcomes not concerned with PO/POL or SN2 were excluded. Screening and data extraction were performed by 2 independent reviewers, and results were charted into 10 outcome categories. RESULTS: We identified 28 RCTs and 2 observational studies. Only 1 RCT examined a neurodevelopmental outcome, reporting infants fed SN2 formula had higher fine motor skill scores compared to those fed a vegetable oil formula with a lower amount of SN2; however, only after adjustment for maternal education and at an earlier, but not a later time point. Anthropometric measures do not appear to be influenced by PO/POL or SN2 within formulas. Alternatively, it was reported that infants fed PO/POL within formulas had a decreased absorption of calcium, total fat, and PA compared to those fed vegetable oil formulas. However, studies were heterogenous, making it difficult to isolate the effects of PO/POL or SN2 in formulas. CONCLUSIONS: Our review reiterates the need for future studies to address the effects of PO/POL and SN2 on neurodevelopment in infants. This study is registered at Open Science Framework as osf.io/697he.


Assuntos
Fórmulas Infantis , Palmitatos , Alimentos Formulados , Humanos , Lactente , Recém-Nascido , Óleo de Palmeira , Óleos de Plantas
5.
FEMS Yeast Res ; 21(2)2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33571365

RESUMO

Oleaginous yeasts have the ability to store greater than 20% of their mass as neutral lipids, in the form of triacylglycerides. The ATP citrate lyase is thought to play a key role in triacylglyceride synthesis, but the relationship between expression levels of this and other related enzymes is not well understood in the role of total lipid accumulation conferring the oleaginous phenotype. We conducted comparative proteomic analyses with the oleaginous yeast, Yarrowia lipolytica, grown in either nitrogen-sufficient rich media or nitrogen-limited minimal media. Total proteins extracted from cells collected during logarithmic and late stationary growth phases were analyzed by 1D liquid chromatography, followed by mass spectroscopy. The ATP citrate lyase enzyme was expressed at similar concentrations in both conditions, in both logarithmic and stationary phase, but many upstream and downstream enzymes showed drastically different expression levels. In non-lipogenic conditions, several pyruvate enzymes were expressed at higher concentration. These enzymes, especially the pyruvate decarboxylase and pyruvate dehydrogenase, may be regulating carbon flux away from central metabolism and reducing the amount of citrate being produced in the mitochondria. While crucial for the oleaginous phenotype, the constitutively expressed ATP citrate lyase appears to cleave citrate in response to carbon flux upstream from other enzymes creating the oleaginous phenotype.


Assuntos
Expressão Gênica , Metabolismo dos Lipídeos/genética , Lipídeos/genética , Nitrogênio/metabolismo , Proteoma/genética , Yarrowia/genética , Yarrowia/metabolismo , Simulação por Computador , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteoma/análise , Proteômica/métodos , Yarrowia/química
6.
Glia ; 68(1): 161-177, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31453649

RESUMO

Schwann cell (SC)-specific monocarboxylate transporter 1 (MCT1) knockout mice were generated by mating MCT1 f/f mice with myelin protein zero (P0)-Cre mice. P0-Cre+/- , MCT1 f/f mice have no detectable early developmental defects, but develop hypomyelination and reduced conduction velocity in sensory, but not motor, peripheral nerves during maturation and aging. Furthermore, reduced mechanical sensitivity is evident in aged P0-Cre+/- , MCT1 f/f mice. MCT1 deletion in SCs impairs both their glycolytic and mitochondrial functions, leading to altered lipid metabolism of triacylglycerides, diacylglycerides, and sphingomyelin, decreased expression of myelin-associated glycoprotein, and increased expression of c-Jun and p75-neurotrophin receptor, suggesting a regression of SCs to a less mature developmental state. Taken together, our results define the contribution of SC MCT1 to both SC metabolism and peripheral nerve maturation and aging.


Assuntos
Envelhecimento/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Bainha de Mielina/metabolismo , Células de Schwann/metabolismo , Células Receptoras Sensoriais/metabolismo , Simportadores/metabolismo , Envelhecimento/genética , Animais , Células Cultivadas , Feminino , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Transportadores de Ácidos Monocarboxílicos/deficiência , Transportadores de Ácidos Monocarboxílicos/genética , Bainha de Mielina/genética , Condução Nervosa/fisiologia , Nervo Sural/metabolismo , Simportadores/deficiência , Simportadores/genética
7.
Artigo em Inglês | MEDLINE | ID: mdl-32579905

RESUMO

The transcription factor Nrf2 and its negative regulator Keap1 play important roles in the maintenance of redox homeostasis in animal cells. Nrf2 activates defenses against oxidative stress and xenobiotics. Homologs of Nrf2 and Keap1 are present in Drosophila melanogaster (CncC and dKeap1, respectively). The aim of this study was to explore effects of CncC deficiency (due to mutation in the cnc gene) or enhanced activity (due to mutation in the dKeap1 gene) on redox status and energy metabolism of young adult flies in relation to behavioral traits and resistance to a number of stressors. Deficiency in either CncC or dKeap1 delayed pupation and increased climbing activity and heat stress resistance in 2-day-old adult flies. Males and females of the ∆keap1 line shared some similarities such as elevated antioxidant defense as well as lower triacylglyceride and higher glucose levels. Males of the ∆keap1 line also had a higher activity of hexokinase, whereas ∆keap1 females showed higher glycogen levels and lower values of respiratory control and ATP production than flies of the control line. Mutation of cnc gene in allele cncEY08884 caused by insertion of P{EPgy2} transposon in cnc promotor did not affect significantly the levels of metabolites and redox parameters, and even activated some components of antioxidant defense. These data suggest that the mutation can be hypomorphic as well as CncC protein can be dispensable for adult fruit flies under physiological conditions. In females, CncC mutation led to lower mitochondrial respiration, higher hexokinase activity and higher fecundity as compared with the control line. Either CncC activation or its deficiency affected stress resistance of flies.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Mutação , Proteínas Repressoras/genética , Animais , Antioxidantes/metabolismo , Drosophila melanogaster/embriologia , Feminino , Glicogênio/metabolismo , Peróxido de Hidrogênio/química , Masculino , Mitocôndrias/metabolismo , Nitroprussiato/química , Oxirredução , Estresse Oxidativo , Temperatura , Xenobióticos
8.
J Bacteriol ; 200(10)2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29507089

RESUMO

Myxococcus xanthus cells produce lipid bodies containing triacylglycerides during fruiting body development. Fatty acid ß-oxidation is the most energy-efficient pathway for lipid body catabolism. In this study, we used mutants in fadJ (MXAN_5371 and MXAN_6987) and fadI (MXAN_5372) homologs to examine whether ß-oxidation serves an essential developmental function. These mutants contained more lipid bodies than the wild-type strain DK1622 and 2-fold more flavin adenine dinucleotide (FAD), consistent with the reduced consumption of fatty acids by ß-oxidation. The ß-oxidation pathway mutants exhibited differences in fruiting body morphogenesis and produced spores with thinner coats and a greater susceptibility to thermal stress and UV radiation. The MXAN_5372/5371 operon is upregulated in sporulating cells, and its expression could not be detected in csgA, fruA, or mrpC mutants. Lipid bodies were found to persist in mature spores of DK1622 and wild strain DK851, suggesting that the roles of lipid bodies and ß-oxidation may extend to spore germination.IMPORTANCE Lipid bodies act as a reserve of triacylglycerides for use when other sources of carbon and energy become scarce. ß-Oxidation is essential for the efficient metabolism of fatty acids associated with triacylglycerides. Indeed, the disruption of genes in this pathway has been associated with severe disorders in animals and plants. Myxococcus xanthus, a model organism for the study of development, is ideal for investigating the complex effects of altered lipid metabolism on cell physiology. Here, we show that ß-oxidation is used to consume fatty acids associated with lipid bodies and that the disruption of the ß-oxidation pathway is detrimental to multicellular morphogenesis and spore formation.


Assuntos
Ácidos Graxos/metabolismo , Metabolismo dos Lipídeos , Myxococcus xanthus/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Flavina-Adenina Dinucleotídeo/metabolismo , Mutação , Myxococcus xanthus/genética , Oxirredução , Fenótipo , Transdução de Sinais , Esporos Bacterianos/crescimento & desenvolvimento , Esporos Bacterianos/efeitos da radiação , Raios Ultravioleta
9.
Plant Cell Environ ; 41(10): 2390-2403, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29813189

RESUMO

Salt stress causes dramatic changes in the organization and dynamic properties of membranes, however, little is known about the underlying mechanisms involved. Modified trichomes, known as epidermal bladder cells (EBC), on the leaves and stems of the halophyte Mesembryanthemum crystallinum can be successfully exploited as a single-cell-type system to investigate salt-induced changes to cellular lipid composition. In this study, alterations in key molecular species from different lipid classes highlighted an increase in phospholipid species, particularly those from phosphatidylcholine and phosphatidic acid (PA), where the latter is central to the synthesis of membrane lipids. Triacylglycerol (TG) species decreased during salinity, while there was little change in plastidic galactolipids. EBC transcriptomic and proteomic data mining revealed changes in genes and proteins involved in lipid metabolism and the upregulation of transcripts for PIPKIB, PI5PII, PIPKIII, and phospholipase D delta suggested the induction of signalling processes mediated by phosphoinositides and PA. TEM and flow cytometry showed the dynamic nature of lipid droplets in these cells under salt stress. Altogether, this work indicates that the metabolism of TG might play an important role in EBC response to salinity as either an energy reserve for sodium accumulation and/or driving membrane biosynthesis for EBC expansion.


Assuntos
Metabolismo dos Lipídeos , Mesembryanthemum/metabolismo , Epiderme Vegetal/citologia , Plantas Tolerantes a Sal/metabolismo , Lipídeos de Membrana/metabolismo , Mesembryanthemum/citologia , Ácidos Fosfatídicos/metabolismo , Fosfatidilcolinas/metabolismo , Epiderme Vegetal/metabolismo , Folhas de Planta/citologia , Folhas de Planta/metabolismo , Caules de Planta/citologia , Caules de Planta/metabolismo , Estresse Salino , Plantas Tolerantes a Sal/citologia , Sódio/metabolismo , Triglicerídeos/metabolismo
10.
Biotechnol Bioeng ; 115(4): 932-942, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29313898

RESUMO

Chain length and degree of saturation plays an important role for the characteristics of various products derived from fatty acids, such as fuels, cosmetics, and food additives. The seeds of Theobroma cacao are the source of cocoa butter, a natural lipid of high interest for the food and cosmetics industry. Cocoa butter is rich in saturated fatty acids that are stored in the form of triacylglycerides (TAGs). One of the major TAG species of cocoa butter, consisting of two stearic acid molecules and one oleic acid molecule (stearic acid-oleic acid-stearic acid, sn-SOS), is particularly rare in nature as the saturated fatty acid stearic acid is typically found only in low abundance. Demand for cocoa butter is increasing, yet T. cacao can only be cultivated in some parts of the tropics. Alternative means of production of cocoa butter lipids (CBLs) are, therefore, sought after. Yeasts also store fatty acids in the form of TAGs, but these are typically not rich in saturated fatty acids. To make yeast an attractive host for microbial production of CBLs, its fatty acid composition needs to be optimized. We engineered Saccharomyces cerevisiae yeast strains toward a modified fatty acid synthesis. Analysis of the fatty acid profile of the modified strains showed that the fatty acid content as well as the titers of saturated fatty acids and the titers of TAGs were increased. The relative content of potential CBLs in the TAG pool reached up to 22% in our engineered strains, which is a 5.8-fold increase over the wild-type. SOS content reached a level of 9.8% in our engineered strains, which is a 48-fold increase over the wild type.


Assuntos
DNA Fúngico/genética , Gorduras na Dieta/metabolismo , Ácidos Oleicos/metabolismo , Saccharomyces cerevisiae/enzimologia , Ácidos Esteáricos/metabolismo , Acetiltransferases/genética , Acetiltransferases/metabolismo , Gorduras na Dieta/análise , Escherichia coli/genética , Engenharia Metabólica , Ácidos Oleicos/análise , Regiões Promotoras Genéticas/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Ácidos Esteáricos/análise , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo
11.
Can J Microbiol ; 64(4): 277-289, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29394487

RESUMO

Relationships between lipid and carotenoid synthesis by Rhodosporidium diobovatum were investigated for cell cultures in nitrogen-limited medium (GMY) containing equimolar amounts of carbon of glucose or glycerol. The cultures were also supplemented with additional substrate at 120 h postinoculation (pi) and during a fed-batch experiment. Growth of R. diobovatum on glucose resulted in higher yields of triacyglycerides (TAGs) and carotenoid than when grown on glycerol, even though the cultures contained equimolar amounts of carbon. After the addition of fresh substrate at 120 h pi, total carotenoid concentrations were significantly different from the concentrations measured at 120 h pi in both glucose and glycerol cultures, with no concomitant increase in lipid concentrations, suggesting that carotenoid synthesis is linked to exponential-phase growth, while lipid synthesis is linked to stationary phase. We also compared the calculated properties of biodiesel that could be made with TAGs derived from R. diobovatum with properties of biodiesel made from TAGs of other oleaginous yeasts, microalgae, vegetable oils, and animal fats. This study shows that R. diobovatum can be an effective strain for production of neutral lipids containing high percentages of oleic acid, palmitic acid, and linoleic acid, as well as carotenoids.


Assuntos
Basidiomycota/metabolismo , Biocombustíveis , Carotenoides/biossíntese , Glucose/metabolismo , Glicerol/metabolismo , Lipídeos/biossíntese , Carbono , Nitrogênio , Leveduras/crescimento & desenvolvimento
12.
Artigo em Inglês | MEDLINE | ID: mdl-29054808

RESUMO

There are very few studies that have directly analyzed the effects of dietary intake of slowly digestible starches on metabolic parameters of animals. The present study examined the effects of slowly digestible starch with high amylose content (referred also as amylose starch) either alone, or in combination with metformin on the development, lifespan, and levels of glucose and storage lipids in the fruit fly Drosophila melanogaster. Consumption of amylose starch in concentrations 0.25-10% did not affect D. melanogaster development, whereas 20% starch delayed pupation and reduced the number of larvae that reached the pupal stage. Starch levels in larval food, but not in adult food, determined levels of triacylglycerides in eight-day-old adult flies. Rearing on diet with 20% starch led to shorter lifespan and a higher content of triacylglycerides in the bodies of adult flies as compared with the same parameters in flies fed on 4% starch diet. Food supplementation with 10mM metformin partly attenuated the negative effects of high starch concentrations on larval pupation and decreased triacylglyceride levels in adult flies fed on 20% starch. Long-term consumption of diets supplemented with metformin and starch decreased lifespan of the insects, compared with the diet supplemented with starch only. The data show that in Drosophila high starch consumption may induce a fat fly phenotype and metformin may partially prevent it.


Assuntos
Adiposidade/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Animal , Drosophila melanogaster/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Metformina/farmacologia , Amido/efeitos adversos , Amilose/efeitos adversos , Animais , Comportamento Animal/efeitos dos fármacos , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/fisiologia , Feminino , Glucose/metabolismo , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento , Pupa/fisiologia , Caracteres Sexuais , Análise de Sobrevida , Triglicerídeos/metabolismo
13.
Molecules ; 23(1)2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29329227

RESUMO

A full understanding of the origin, formation and degradation of volatile compounds that contribute to wine aroma is required before wine style can be effectively managed. Fractionation of grapes represents a convenient and robust method to simplify the grape matrix to enhance our understanding of the grape contribution to volatile compound production during yeast fermentation. In this study, acetone extracts of both Riesling and Cabernet Sauvignon grape berries were fractionated and model wines produced by spiking aliquots of these grape fractions into model grape juice must and fermented. Non-targeted SPME-GCMS analyses of the wines showed that several medium chain fatty acid ethyl esters were more abundant in wines made by fermenting model musts spiked with certain fractions. Further fractionation of the non-polar fractions and fermentation of model must after addition of these fractions led to the identification of a mixture of polyunsaturated triacylglycerides that, when added to fermenting model must, increase the concentration of medium chain fatty acid ethyl esters in wines. Dosage-response fermentation studies with commercially-available trilinolein revealed that the concentration of medium chain fatty acid ethyl esters can be increased by the addition of this triacylglyceride to model musts. This work suggests that grape triacylglycerides can enhance the production of fermentation-derived ethyl esters and show that this fractionation method is effective in segregating precursors or factors involved in altering the concentration of fermentation volatiles.


Assuntos
Produtos Biológicos/química , Ésteres/química , Triglicerídeos/química , Vitis/química , Acetona/química , Produtos Biológicos/isolamento & purificação , Ácidos Graxos/química , Fermentação , Aromatizantes/química , Frutas/química , Humanos , Odorantes/análise , Saccharomyces cerevisiae , Triglicerídeos/isolamento & purificação , Compostos Orgânicos Voláteis/química , Vinho/análise
14.
Exp Cell Res ; 320(2): 302-10, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24200503

RESUMO

Fatty acid synthase is over-expressed in many cancers and its activity is required for cancer cell survival, but the role of endogenously synthesized fatty acids in cancer is unknown. It has been suggested that endogenous fatty acid synthesis is either needed to support the growth of rapidly dividing cells, or to maintain elevated glycolysis (the Warburg effect) that is characteristic of cancer cells. Here, we investigate both hypotheses. First, we compared utilization of fatty acids synthesized endogenously from (14)C-labeled acetate to those supplied exogenously as (14)C-labeled palmitate in the culture medium in human breast cancer (MCF-7 and MDA-MB-231) and untransformed breast epithelial cells (MCF-10A). We found that cancer cells do not produce fatty acids that are different from those derived from exogenous palmitate, that these fatty acids are esterified to the same lipid and phospholipid classes in the same proportions, and that their distribution within neutral lipids is not different from untransformed cells. These results suggest that endogenously synthesized fatty acids do not fulfill a specific function in cancer cells. Furthermore, we observed that cancer cells excrete endogenously synthesized fatty acids, suggesting that they are produced in excess of requirements. We next investigated whether lipogenic activity is involved in the maintenance of high glycolytic activity by culturing both cancer and non-transformed cells under anoxic conditions. Although anoxia increased glycolysis 2-3 fold, we observed no concomitant increase in lipogenesis. Our results indicate that breast cancer cells do not have a specific qualitative or quantitative requirement for endogenously synthesized fatty acids and that increased de novo lipogenesis is not required to sustain elevations in glycolytic activity induced by anoxia in these cells.


Assuntos
Ácido Graxo Sintase Tipo I/fisiologia , Ácidos Graxos/metabolismo , Glicólise , Neoplasias/metabolismo , Fosfolipídeos/biossíntese , Hipóxia Celular/fisiologia , Células Cultivadas , Esterificação , Feminino , Glicólise/genética , Humanos , Metabolismo dos Lipídeos , Lipogênese/fisiologia , Células MCF-7 , Neoplasias/genética
15.
Biochim Biophys Acta ; 1832(12): 2103-14, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23928362

RESUMO

Lipin-1 deficiency is associated with massive rhabdomyolysis episodes in humans, precipitated by febrile illnesses. Despite well-known roles of lipin-1 in lipid biosynthesis and transcriptional regulation, the pathogenic mechanisms leading to rhabdomyolysis remain unknown. Here we show that primary myoblasts from lipin-1-deficient patients exhibit a dramatic decrease in LPIN1 expression and phosphatidic acid phosphatase 1 activity, and a significant accumulation of lipid droplets (LD). The expression levels of LPIN1-target genes [peroxisome proliferator-activated receptors delta and alpha (PPARδ, PPARα), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), acyl-coenzyme A dehydrogenase, very long (ACADVL), carnitine palmitoyltransferase IB and 2 (CPT1B and CPT2)] were not affected while lipin-2 protein level, a closely related member of the family, was increased. Microarray analysis of patients' myotubes identified 19 down-regulated and 51 up-regulated genes, indicating pleiotropic effects of lipin-1 deficiency. Special attention was paid to the up-regulated ACACB (acetyl-CoA carboxylase beta), a key enzyme in the fatty acid synthesis/oxidation balance. We demonstrated that overexpression of ACACB was associated with free fatty acid accumulation in patients' myoblasts whereas malonyl-carnitine (as a measure of malonyl-CoA) and CPT1 activity were in the normal range in basal conditions accordingly to the normal daily activity reported by the patients. Remarkably ACACB invalidation in patients' myoblasts decreased LD number and size while LPIN1 invalidation in controls induced LD accumulation. Further, pro-inflammatory treatments tumor necrosis factor alpha+Interleukin-1beta(TNF1α+IL-1ß) designed to mimic febrile illness, resulted in increased malonyl-carnitine levels, reduced CPT1 activity and enhanced LD accumulation, a phenomenon reversed by dexamethasone and TNFα or IL-1ß inhibitors. Our data suggest that the pathogenic mechanism of rhabdomyolysis in lipin-1-deficient patients combines the predisposing constitutive impairment of lipid metabolism and its exacerbation by pro-inflammatory cytokines.


Assuntos
Citocinas/farmacologia , Mediadores da Inflamação/farmacologia , Transtornos do Metabolismo dos Lipídeos/etiologia , Lipídeos , Fibras Musculares Esqueléticas/patologia , Mioblastos/patologia , Fosfatidato Fosfatase/genética , Biomarcadores/metabolismo , Western Blotting , Estudos de Casos e Controles , Ciclo Celular , Proliferação de Células , Criança , Pré-Escolar , Estresse do Retículo Endoplasmático , Feminino , Perfilação da Expressão Gênica , Humanos , Transtornos do Metabolismo dos Lipídeos/metabolismo , Transtornos do Metabolismo dos Lipídeos/patologia , Masculino , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Mutação/genética , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Associadas a Pancreatite , Fosfatidato Fosfatase/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rabdomiólise/etiologia , Rabdomiólise/metabolismo , Rabdomiólise/patologia
16.
Food Res Int ; 177: 113864, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38225135

RESUMO

Cocoa butter equivalents (CBE) are mixtures of triglycerides from multiple sources (e.g., sunflower oil, mango kernel and sal), which resemble cocoa butter (CB) in both physical and chemical properties. Despite being widely used to replace CB in chocolate products, the crystallization behavior of many CBEs is still poorly understood. The aim of this work was to develop a fundamental understanding, at the molecular level, of the crystallization behavior of selected CBEs, and compare it with that of CB. Chromatography was used to determine the composition of CBEs, in terms of fatty acids and triacylglycerides (TAGs), while their thermodynamic behavior and crystallization kinetics were studied using polarized microscopy, differential calorimetry and three different synchrotron X-ray scattering setups. CBEs of different origin and chemical composition (e.g., different ratios of the main CB TAGs, namely POP, SOS and POS) crystallized in different polymorphs and with different kinetics of nucleation, growth and polymorphic transformation. SOS rich CBEs presented showed more polymorphs than CB and POP rich samples; whereas, CBEs with high concentration of POP showed slow kinetic of polymorphic transformation towards the stable ß(3L) form. Additionally, it was observed that the presence of small amounts (<1% w/w) of specific TAGs, such as OOO, PPP or SSS, could significantly affect the crystallization behavior of CBEs and CBs in terms of kinetics of polymorphic transformation and number of phases detected (multiple high melting ß(2L) polymorphs were identified in all samples studied). Finally, it was found that, regardless of the CBE composition, the presence of shear could promote the formation of stable ß polymorphs over metastable ß' and γ forms, and reduced the size of the crystal agglomerates formed due to increased secondary nucleation.


Assuntos
Ácidos Graxos , Síncrotrons , Cristalização , Raios X , Triglicerídeos/química , Ácidos Graxos/análise
17.
Biomedicines ; 12(6)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38927486

RESUMO

According to the World Health Organization, ischemic stroke is the second leading cause of death in the world. Frequently, it is caused by brachiocephalic artery (BCA) atherosclerosis. Timely detection of atherosclerosis and its unstable course can allow for a timely response to potentially dangerous changes and reduce the risk of vascular complications. Omics technologies allow us to identify new biomarkers that we can use in diagnosing diseases. This research included 90 blood plasma samples. The study group comprised 52 patients with severe atherosclerotic lesions BCA, and the control group comprised 38 patients with no BCA atherosclerosis. Targeted and panoramic lipidomic profiling of their blood plasma was carried out. There was a statistically significant difference (p < 0.05) in the values of the indices saturated fatty acids (FAs), unsaturated FAs, monounsaturated FAs, omega-3, and omega-6. Based on the results on the blood plasma lipidome, we formed models that have a fairly good ability to determine atherosclerotic lesions of the brachiocephalic arteries, as well as a model for identifying unstable atherosclerotic plaques. According only to the panoramic lipidome data, divided into groups according to stable and unstable atherosclerotic plaques, a significant difference was taken into account: p value < 0.05 and abs (fold change) > 2. Unfortunately, we did not observe significant differences according to the established plasma panoramic lipidome criteria between patients with stable and unstable plaques. Omics technologies allow us to obtain data about any changes in the body. According to our data, statistically significant differences in lipidomic profiling were obtained when comparing groups with or without BCA atherosclerosis.

18.
Methods Mol Biol ; 2769: 189-198, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38315398

RESUMO

The metabolic rearrangements of hepatic metabolism associated with liver cancer are still incompletely understood. There is an ongoing need to identify novel and more efficient diagnostic biomarkers and therapeutic targets based on the metabolic mechanisms of these diseases. In comparison to traditional diagnostic biomarkers, metabolomics is a comprehensive technique for discovering chemical signatures for liver cancer screening, prediction, and earlier diagnosis. Lipids are a large and diverse group of complex biomolecules that are at the heart of liver physiology and play an important role in the development and progression of cancer. In this chapter, we described two detailed protocols for targeted lipids analysis: glycerophospholipids and mono, di, tri-acylglycerides, both by Flow Injection Analysis (FIA) HPLC coupled to a SelexIon/QTRAP 6500+ system. These approaches provide a targeted lipidomic metabolomic signature of dissimilar metabolic disorders affecting liver cancers.


Assuntos
Glicerofosfolipídeos , Neoplasias Hepáticas , Humanos , Metabolômica/métodos , Biomarcadores
19.
J Pharm Biomed Anal ; 222: 115112, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36274478

RESUMO

Intravenous lipid emulsions (ILEs) are used for parenteral nutrition, providing a vital source of essential fatty acids and concentrated energy for patients who are unable to absorb nutrients via the digestive track. They are commonly used to treat local and non-local anesthetic toxicity, and lipophilic drug overdose. ILE are composed of natural lipids, and the composition of these natural lipids can be varied based on their source. The lipids are susceptible to hydrolytic degradation with time, resulting various lipid degradation products such as Lysophosphatidylcholines (LPs), affecting the actual composition of nutrients in the formulation. As a result, the identification and quantification of lipid components, including degradation products, in ILEs are crucial in quality control. In this study, lipids from different batches of ILE Intralipid® 20%, were separated and identified using a UHPLC-ESI-QTOF system and SimLipid® high throughput lipid identification software. Out of 47 lipids identified, 34 were phospholipids (PLs) and the others were triacylglycerols (TAGs). Most of the phospholipids detected were phosphatidylcholines (PC) and Lysophosphatidylcholines (LPC). A total of 9 LPCs, 18 PCs, 6 phosphoethanolamines (PEs), and 1 sphingomyelin (SM) were identified. The LPCs concentration changed with the manufacturing date and storage time. This UHPLC method enabled the identification and quantification of lipids and their decomposition products in complex ILE emulsion mixtures on a single 20-minute chromatographic run.


Assuntos
Emulsões Gordurosas Intravenosas , Lisofosfatidilcolinas , Humanos , Triglicerídeos/análise , Fosfolipídeos/análise , Emulsões , Nutrição Parenteral , Fosfatidilcolinas
20.
Lipids ; 58(6): 257-270, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37997471

RESUMO

Consumption of a Western diet (WD) is known to increase the risk of obesity. Short or medium chain fatty acids influence energy metabolism, and triacetin, a synthetic short chain triacylglyceride, has been shown to lower body fat under normal conditions. This study aimed to investigate if triacetin as part of a WD modifies rat weight and body fat. Male rats were fed a control diet or WD for 8 weeks. At week 8, rats in the WD group were maintained on a WD diet or switched to a WD diet containing 30% energy from medium-chain triacylglyceride (WD-MCT) or triacetin (WD-T) for another 8 weeks. At week 16, rats were euthanized and liver, adipose and blood were collected. Tissue fatty acids (FAs) were quantified by gas chromatography (GC) and hepatic FAs were measured by GC-combustion-isotope ratio mass spectrometry for δ13 C-palmitic acid (PAM)-a novel marker of de novo lipogenesis (DNL). Rats fed WD-T had a body weight not statistically different to the control group, and gained less body weight than rats fed WD alone. Furthermore, WD-T fed rats had a lower fat mass, and lower total liver and plasma FAs compared to the WD group. Rats fed WD-T did not differ from WD in blood ketone or glucose levels, however, had a significantly lower hepatic δ13 C-PAM value than WD fed rats; suggestive of lower DNL. In summary, we show that triacetin has the potential to blunt weight gain and adipose tissue accumulation in a rodent model of obesity, possibly due to a decrease in DNL.


Assuntos
Obesidade , Triacetina , Ratos , Masculino , Animais , Triacetina/metabolismo , Triacetina/farmacologia , Peso Corporal , Cromatografia Gasosa-Espectrometria de Massas , Obesidade/metabolismo , Dieta , Fígado/metabolismo , Aumento de Peso , Ácidos Graxos/metabolismo
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