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1.
Prep Biochem Biotechnol ; 53(9): 1154-1163, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36794850

RESUMEN

Lignocellulosic residues, such as cocoa bean shell (FI), are generated in large quantities during agro-industrial activities. Proper management of residual biomass through solid state fermentation (SSF) can be effective in obtaining value-added products. The hypothesis of the present work is that the bioprocess promoted by P. roqueforti can lead to structural changes in the fibers of the fermented cocoa bean shell (FF) that confer characteristics of industrial interest. To unveil such changes, the techniques of FTIR, SEM, XRD, TGA/TG were used. After SSF, an increase of 36.6% in the crystallinity index was observed, reflecting the reduction of amorphous components such as lignin in the FI residue. Furthermore, an increase in porosity was observed through the reduction of the 2θ angle, which gives the FF a potential candidate for applications of porous products. The FTIR results confirm the reduction in hemicellulose content after SSF. The thermal and thermogravimetric tests showed an increase in the hydrophilicity and thermal stability of FF (15% decomposition) in relation to the by-product FI (40% decomposition). These data provided important information regarding changes in the crystallinity of the residue, existing functional groups and changes in degradation temperatures.


This work presents a new approach for solid state fermentation based on the study of structural changes caused by Penicillium roquefort, which is important to understand the changes in the lignocellulosic matrix after the fungus growth. The results provided important information regarding changes in the crystallinity of the residue, existing functional groups and changes in degradation temperatures. Consequently, they can help in proposals for the total use of the residual solid after fermentation, as well as contribute to reducing the lack of this information in the literature.


Asunto(s)
Penicillium , Penicillium/metabolismo , Lignina/metabolismo , Fermentación
2.
Biopolymers ; 113(6): e23488, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35338709

RESUMEN

Produced water (PW) and crude glycerin (CG) are compounds overproduced by the oil and biodiesel industry and significant scientific efforts are being applied for properly recycling them. The aim of this research is to combine such industrial byproducts for sustaining the production of xanthan by Xanthomonas campestris. Xanthan yields and viscosity on distinct PW ratios (0, 10, 15, 25, 50, 100) and on 100% dialyzed PW (DPW) in shaker batch testing identified DPW treatment as the best approach for further bioreactor experiments. Such experiments showed a xanthan yield of 17.3 g/L within 54 h and a viscosity of 512 mPa s. Physical-chemical characterization (energy dispersive X-ray spectroscopy, scanning electron microscopy and Raman spectroscopy) showed similarities between the produced gum and the experimental control. This research shows a clear alternative for upcycling high salinity PW and CG for the generation of a valued bioproduct for the oil industry.


Asunto(s)
Polisacáridos Bacterianos , Xanthomonas campestris , Glicerol , Polisacáridos Bacterianos/química , Viscosidad , Agua
3.
J Physiol ; 595(3): 677-693, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-27647415

RESUMEN

KEY POINTS: Long-chain acyl-CoA synthetase 6 (ACSL6) mRNA is present in human and rat skeletal muscle, and is modulated by nutritional status: exercise and fasting decrease ACSL6 mRNA, whereas acute lipid ingestion increase its expression. ACSL6 genic inhibition in rat primary myotubes decreased lipid accumulation, as well as activated the higher mitochondrial oxidative capacity programme and fatty acid oxidation through the AMPK/PGC1-α pathway. ACSL6 overexpression in human primary myotubes increased phospholipid species and decreased oxidative metabolism. ABSTRACT: Long-chain acyl-CoA synthetases (ACSL 1 to 6) are key enzymes regulating the partitioning of acyl-CoA species toward different metabolic fates such as lipid synthesis or ß-oxidation. Despite our understanding of ecotopic lipid accumulation in skeletal muscle being associated with metabolic diseases such as obesity and type II diabetes, the role of specific ACSL isoforms in lipid synthesis remains unclear. In the present study, we describe for the first time the presence of ACSL6 mRNA in human skeletal muscle and the role that ACSL6 plays in lipid synthesis in both rodent and human skeletal muscle. ACSL6 mRNA was observed to be up-regulated by acute high-fat meal ingestion in both rodents and humans. In rats, we also demonstrated that fasting and chronic aerobic training negatively modulated the ACSL6 mRNA and other genes of lipid synthesis. Similar results were obtained following ACSL6 knockdown in rat myotubes, which was associated with a decreased accumulation of TAGs and lipid droplets. Under the same knockdown condition, we further demonstrate an increase in fatty acid content, p-AMPK, mitochondrial content, mitochondrial respiratory rates and palmitate oxidation. These results were associated with increased PGC-1α, UCP2 and UCP3 mRNA and decreased reactive oxygen species production. In human myotubes, ACSL6 overexpression reduced palmitate oxidation and PGC-1α mRNA. In conclusion, ACSL6 drives acyl-CoA toward lipid synthesis and its downregulation improves mitochondrial biogenesis, respiratory capacity and lipid oxidation. These outcomes are associated with the activation of the AMPK/PGC1-α pathway.


Asunto(s)
Coenzima A Ligasas/metabolismo , Metabolismo de los Lípidos/fisiología , Mitocondrias Musculares/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Animales , Células Cultivadas , Citrato (si)-Sintasa/metabolismo , Coenzima A Ligasas/genética , Dieta Alta en Grasa , Ácidos Grasos/metabolismo , Femenino , Humanos , Masculino , Obesidad/metabolismo , Oxidación-Reducción , Consumo de Oxígeno , ARN Mensajero/metabolismo , Ratas Wistar
4.
J Cell Biochem ; 118(11): 3846-3854, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28387439

RESUMEN

In chemoresistant leukemia cells (Lucena-1), the low molecular weight protein tyrosine phosphatase (LMWPTP) is about 20-fold more active than in their susceptible counterpart (K562). We found this phosphatase ensures the activated statuses of Src and Bcr-Abl. Since, phosphorylation and dephosphorylation of proteins represent a key post-translational regulation of several enzymes, we also explored the kinome. We hereby show that LMWPTP superactivation, together with kinome reprogramming, cooperate towards glucose addiction. Resistant leukemia cells present lower levels of oxidative metabolism, in part due to downexpression of the following mitochondrial proteins: pyruvate dehydrogenase subunit alpha 1, succinate dehydrogenase, and voltage-dependent anion channel. Those cells displayed higher expression levels of glucose transporter 1 and higher production of lactate. In addition, Lucena-1 siRNA LMWPTP cells showed lower expression levels of glucose transporter 1 and lower activity of lactate dehydrogenase. On the other hand, K562 cells overexpressing LMWPTP presented higher expression/activity of both proteins. In this study, we show that LMWPTP is a pivotal mediator of metabolic reprogramming that confers survival advantages to leukemia cells against death stimuli. J. Cell. Biochem. 118: 3846-3854, 2017. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Resistencia a Antineoplásicos , Glucólisis , Leucemia/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Tirosina Fosfatasas/metabolismo , Transducción de Señal , Enfermedad Aguda , Humanos , Células K562 , Leucemia/patología , Fosforilación
5.
Biochim Biophys Acta ; 1832(10): 1591-604, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23643711

RESUMEN

The mitochondrial redox state plays a central role in the link between mitochondrial overloading and insulin resistance. However, the mechanism by which the ROS induce insulin resistance in skeletal muscle cells is not completely understood. We examined the association between mitochondrial function and H2O2 production in insulin resistant cells. Our hypothesis is that the low mitochondrial oxygen consumption leads to elevated ROS production by a mechanism associated with reduced PGC1α transcription and low content of phosphorylated CREB. The cells were transfected with either the encoded sequence for catalase overexpression or the specific siRNA for catalase inhibition. After transfection, myotubes were incubated with palmitic acid (500µM) and the insulin response, as well as mitochondrial function and fatty acid metabolism, was determined. The low mitochondrial oxygen consumption led to elevated ROS production by a mechanism associated with ß-oxidation of fatty acids. Rotenone was observed to reduce the ratio of ROS production. The elevated H2O2 production markedly decreased the PGC1α transcription, an effect that was accompanied by a reduced phosphorylation of Akt and CREB. The catalase transfection prevented the reduction in the phosphorylated level of Akt and upregulated the levels of phosphorylated CREB. The mitochondrial function was elevated and H2O2 production reduced, thus increasing the insulin sensitivity. The catalase overexpression improved mitochondrial respiration protecting the cells from fatty acid-induced, insulin resistance. This effect indicates that control of hydrogen peroxide production regulates the mitochondrial respiration preventing the insulin resistance in skeletal muscle cells by a mechanism associated with CREB phosphorylation and ß-oxidation of fatty acids.


Asunto(s)
Catalasa/metabolismo , Peróxido de Hidrógeno/metabolismo , Resistencia a la Insulina , Mitocondrias Musculares/fisiología , Animales , Antioxidantes/metabolismo , Células Cultivadas , Masculino , Mitocondrias Musculares/enzimología , Músculo Esquelético/citología , Músculo Esquelético/enzimología , Músculo Esquelético/metabolismo , Consumo de Oxígeno , Ácido Palmítico/farmacología , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Wistar
6.
J Pineal Res ; 57(2): 155-67, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24981026

RESUMEN

Melatonin has a number of beneficial metabolic actions and reduced levels of melatonin may contribute to type 2 diabetes. The present study investigated the metabolic pathways involved in the effects of melatonin on mitochondrial function and insulin resistance in rat skeletal muscle. The effect of melatonin was tested both in vitro in isolated rats skeletal muscle cells and in vivo using pinealectomized rats (PNX). Insulin resistance was induced in vitro by treating primary rat skeletal muscle cells with palmitic acid for 24 hr. Insulin-stimulated glucose uptake was reduced by palmitic acid followed by decreased phosphorylation of AKT which was prevented my melatonin. Palmitic acid reduced mitochondrial respiration, genes involved in mitochondrial biogenesis and the levels of tricarboxylic acid cycle intermediates whereas melatonin counteracted all these parameters in insulin-resistant cells. Melatonin treatment increases CAMKII and p-CREB but had no effect on p-AMPK. Silencing of CREB protein by siRNA reduced mitochondrial respiration mimicking the effect of palmitic acid and prevented melatonin-induced increase in p-AKT in palmitic acid-treated cells. PNX rats exhibited mild glucose intolerance, decreased energy expenditure and decreased p-AKT, mitochondrial respiration, and p-CREB and PGC-1 alpha levels in skeletal muscle which were restored by melatonin treatment in PNX rats. In summary, we showed that melatonin could prevent mitochondrial dysfunction and insulin resistance via activation of CREB-PGC-1 alpha pathway. Thus, the present work shows that melatonin play an important role in skeletal muscle mitochondrial function which could explain some of the beneficial effects of melatonin in insulin resistance states.


Asunto(s)
Resistencia a la Insulina/fisiología , Melatonina/farmacología , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Animales , Células Cultivadas , Ciclo del Ácido Cítrico/efectos de los fármacos , Prueba de Tolerancia a la Glucosa , Masculino , Consumo de Oxígeno/efectos de los fármacos , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacos
7.
N Biotechnol ; 78: 84-94, 2023 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-37820831

RESUMEN

Microalgae-based wastewater treatment has been conceived to obtain reclaimed water and produce microalgal biomass for bio-based products and biofuels generation. However, microalgal biomass harvesting is challenging and expensive, hence one of the main bottlenecks for full-scale implementation. Finding an integrated approach that covers concepts of engineering, green chemistry and the application of microbial anabolism driven towards the harvesting processes, is mandatory for the widespread establishment of full-scale microalgae wastewater treatment plants. By using nature-based substances and applying concepts of chemical functionalization in already established harvesting methods, the costs of harvesting processes could be reduced while preventing microalgae biomass contamination. Moreover, microalgae produced during wastewater treatment have unique culture characteristics, such as the consortia, which are primarily composed of microalgae and bacteria, that should be accounted for prior to downstream processing. The aim of this review is to examine recent advances in microalgal biomass harvesting and recovery in wastewater treatment systems, considering the impact of consortia variability. The costs of available harvesting technologies, such as coagulation/flocculation, coupled to sedimentation and differential air flotation, are provided. Additionally, promising technologies are discussed, including autoflocculation, bioflocculation, new filtration materials, nanotechnology, microfluidic and magnetic methods.


Asunto(s)
Microalgas , Purificación del Agua , Biomasa , Biocombustibles , Floculación
8.
Mol Metab ; 78: 101816, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37821006

RESUMEN

OBJECTIVE: The mitochondrial unfolded protein response (UPRmt) is an adaptive cellular response to stress to ensure mitochondrial proteostasis and function. Here we explore the capacity of physical exercise to induce UPRmt in the skeletal muscle. METHODS: Therefore, we combined mouse models of exercise (swimming and treadmill running), pharmacological intervention, and bioinformatics analyses. RESULTS: Firstly, RNA sequencing and Western blotting analysis revealed that an acute aerobic session stimulated several mitostress-related genes and protein content in muscle, including the UPRmt markers. Conversely, using a large panel of isogenic strains of BXD mice, we identified that BXD73a and 73b strains displayed low levels of several UPRmt-related genes in the skeletal muscle, and this genotypic feature was accompanied by body weight gain, lower locomotor activity, and aerobic capacity. Finally, we identified that c-Jun N-terminal kinase (JNK) activation was critical in exercise-induced UPRmt in the skeletal muscle since pharmacological JNK pathway inhibition blunted exercise-induced UPRmt markers in mice muscle. CONCLUSION: Our findings provide new insights into how exercise triggers mitostress signals toward the oxidative capacity in the skeletal muscle.


Asunto(s)
Proteínas Quinasas JNK Activadas por Mitógenos , Condicionamiento Físico Animal , Animales , Ratones , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Mitocondrias/metabolismo , Músculo Esquelético/metabolismo , Respuesta de Proteína Desplegada , Proteína Quinasa 8 Activada por Mitógenos/metabolismo
9.
J Photochem Photobiol B ; 226: 112356, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34801926

RESUMEN

Oil recovery is a challenge and microbial enhanced oil recovery is an option. We theorized that the use of produced water (PW) with photo-stimulation could influence both production and viscosity of Xanthan gum. This study aimed at the evaluation of the effect of photo-stimulation by λ630 ± 1 ηm LED light on the biosynthesis of Xanthan gum produced by Xanthomonas campestris IBSBF 2103 strain reusing PW of the oil industry. We assessed the effect of photo-stimulation by LED light (λ630 nm) on the biosynthesis of Xanthan gum produced by X. campestris in medium containing produced water. Different energy densities applied during the microbial growth phase were tested. The highest production was achieved when using 12 J/cm2 LED light (p < 0.01). Three protocols were assessed: Non-irradiated (Control), Irradiation with LED light during the growth phase (LEDgrowth) and Irradiation with LED light during both growth and production phases (LED growth+production). Both the amount and viscosity of the xanthan gum was significantly higher (p < 0.01) in the group LEDgrowth+production. The study showed that LED irradiation (λ630 ± 1 ηm) during both the growth and production phases of the biopolymer increased both the production and viscosity of Xanthan gum.


Asunto(s)
Viscosidad
10.
J Photochem Photobiol B ; 213: 112052, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33074141

RESUMEN

Produced water (PW) is a by-product generated throughout oil exploration. Geological formation and geographical location of the reservoir influence its physical, chemical and biological characteristics. Xanthan gum (XG), an exopolysaccharide (EPS) produced by Xanthomonas campestris, has been widely used in enhanced oil recovery (EOR) technology because of its high viscosity, pseudoplastic behavior, stability in function of salinity, temperature and alkaline conditions. The production of XG may be affected by the composition of the PW, where the acetyl and pyruvyl radicals may be present in the mannoses. The aim of this study was to evaluate the composition of XG produced by X. campestris, particularly the amount of Xanthan, acetyl and pyruvyl groups, in culture mediums containing distilled (DW) or produced (PW) water in different concentrations, by means of dispersive Raman spectroscopy (1064 nm). The spectra of XG showed peaks referred to the main constituents of the Xanthan (glucose, mannose and glucuronic acid). Spectral features assigned to pyruvyl were seen in all samples mainly at ~1010 cm-1, with higher intensity when using DW and 25% PW. PCA loadings showed that the peaks assigned to pyruvyl are consistent to presence of sodium pyruvate (~1040/~1050 and ~ 1432 cm-1) and were higher in the samples obtained in 25% PW. ANOVA GLM applied to Raman peaks of interest (~1010 and ~ 1090 cm-1) and to PCA scores (Score 1 to Score 3) showed that both were influenced by the type of water used in the culture medium, where the XG were strongly reduced in the groups PW compared to DW while the pyruvyl content increased proportionally with the concentration of PW. The results suggest that the composition of the water used in the bacteria's culture medium influenced the composition of XG, including the amount of Xanthan and particularly the pyruvyl content, and therefore needs to be considered when using this approach of injecting XG in oil fields as pyruvyl content affects viscosity.


Asunto(s)
Yacimiento de Petróleo y Gas/microbiología , Polisacáridos Bacterianos/química , Xanthomonas campestris/metabolismo , Glucosa/química , Ácido Glucurónico/química , Manosa/química , Yacimiento de Petróleo y Gas/química , Aceites , Análisis de Componente Principal , Ácido Pirúvico/química , Espectrometría Raman , Viscosidad , Agua/metabolismo
11.
J Photochem Photobiol B ; 213: 112057, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33142219

RESUMEN

Oil is expected to continue to be one of the most important sources of energy in the world and world's energy matrix for the foreseeable future. However, high demand for energy and the decline of the production of oil fields makes oil recovery a challenge. Most techniques used for the recovery process are expensive, non-sustainable and technically difficult to implement. In this context, microbial enhanced oil recovery (MEOR) represents an attractive alternative. It employs products derived from the metabolism of microorganisms that produce biopolymers. Certain bacteria species (e.g., Xanthomonas campestris) produce polysaccharides (exopolysaccharides - EPS) such as the well-known Xanthan gum (XG). We hypothesized that the use of produced water (PW) water in combination photo-stimulation with laser/LED could influence the production and composition of XG. Raman spectroscopy has been used for qualitative and quantitative evaluation of the biochemical composition of XG biopolymer under light stimulation. X. campestris cultures in either distilled water or dialysis-produced water were studied under the absence or presence of laser irradiation (λ = 660 nm, CW, spot size 0.040 cm2, 40 mW, 444 s, 8.0 J/cm2) or LED (λ = 630 nm ± 2 nm, CW, spot size 0.50 cm2, 140 mW, 500 s, 12 J/cm2). XG produced by these cultures was analyzed by Raman spectroscopy at 1064 nm excitation and subjected to principal component analysis (PCA). Results of the exploratory analysis and ANOVA general linear model (GLM) suggested that the extent of XG and pyruvate (pyruvyl mannose) production was affected differentially in X. campestris when cultured in distilled water plus LED photo-stimulation versus dialysis-produced water plus LED photo-stimulation. XG production increased in the distilled water culture. In contrast, both pyruvate acetyl mannose content went up in the dialysis-water culture. These results open a wide field of opportunities in the use of metal-enriched cultures in combination with photo-biomodulation to direct and optimize bacterial production of compounds (i.e., XG) that may be of great benefit in the implementation of sustainable practices for oil extraction.


Asunto(s)
Mezclas Complejas/análisis , Medios de Cultivo/química , Polisacáridos Bacterianos/análisis , Xanthomonas campestris/química , Mezclas Complejas/metabolismo , Medios de Cultivo/metabolismo , Rayos Láser , Polisacáridos Bacterianos/metabolismo , Análisis de Componente Principal , Espectrometría Raman , Viscosidad , Agua
12.
J Photochem Photobiol B ; 191: 38-43, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30562720

RESUMEN

Light biotechnology is a promising tool for enhancing recalcitrant compounds biodegradation. Xenobiotics can cause a significant impact on the quality of the results achieved by sewage treatment systems due to their recalcitrance and toxicity. The optimization of bioremediation and industrial processes, aiming to increase efficiency and income is of great value. The aim of this study was to accelerate and optimize the hydrolysis of Remazol Brilliant Blue R by photo stimulating a thermophilic bacterial consortium. Three experimental groups were studied: control group; LED Group and Laser Group. The control group was exposed to the same conditions as the irradiated groups, except exposure to light. The samples were irradiated in Petri dishes with either a Laser device (λ660 nm, CW, θ = 0.04 cm2, 40 mW, 325 s, 13 J/cm2) or by a LED prototype (λ632 ±â€¯2 nm, CW, θ = 0.5 cm2, 145 mW, 44 s, 13 J/cm2). We found that, within 48-h, statistically significant differences were observed between the irradiated and the control groups in the production of RNA, proteins, as well as in the degradation of the RBBR. It is concluded that, both Laser and LED light irradiation caused increased cellular proliferation, protein production and metabolic activity, anticipating and increasing the catabolism of the RBBR. Being the economic viability a predominant aspect for industrial propose our results indicates that photo stimulation is a low-cost booster of bioprocesses.


Asunto(s)
Antraquinonas/química , Procesos Fotoquímicos , Xenobióticos/metabolismo , Antraquinonas/metabolismo , Antraquinonas/efectos de la radiación , Biodegradación Ambiental , Costos y Análisis de Costo , Hidrólisis , Rayos Láser , Luz , Consorcios Microbianos/efectos de la radiación , Xenobióticos/efectos de la radiación
13.
J Nutr Biochem ; 60: 16-23, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30041048

RESUMEN

Understanding the mitochondrial processes that contribute to body energy metabolism may provide an attractive therapeutic target for obesity and co-morbidities. Here we investigated whether intermittent dietary supplementation with conjugated linoleic (CLA, 18:2n-6), docosahexaenoic (22:6n-3, DHA) and eicosapentaenoic (20:5n-3, EPA) acids, either alone or in combination, changes body metabolism associated with mitochondrial functions in the brain, liver, skeletal muscle and brown adipose tissue (BAT). Male C57Bl/6 mice were divided into groups: CLA (50% cis-9, trans-11; 50% trans-10, cis-12), EPA/DHA (64% EPA; 28% DHA), CLA plus EPA/DHA or control (linoleic acid). Each mouse received 3 g/kg b.w. of the stated oil by gavage on alternating days for 60 days. Dietary supplementation with CLA or EPA/DHA increased body VO2 consumption, VCO2 production and energy expenditure, being fish oil (FO) the most potent even in combination with CLA. Individually, both oils reduced mitochondrial density in BAT. CLA supplementation alone also a) elevated the expression of uncoupling proteins in soleus, liver and hippocampus and the uncoupling activity in the last two, ad this effect was associated with reduced hydrogen peroxide production in hippocampus; b) increased proteins related to mitochondrial fission in liver. EPA/DHA supplementation alone also a) induced mitochondrial biogenesis in liver, soleus and hippocampus associated with increased expression of PGC1-α; b) induced proteins related to mitochondrial fusion in the liver, and fission and fusion in the hippocampus. Therefore, this study shows changes on mitochondrial mechanisms induced by CLA and/or EPA/DHA that can be associated with elevated body energy expenditure.


Asunto(s)
Ácidos Docosahexaenoicos/administración & dosificación , Ácido Eicosapentaenoico/administración & dosificación , Metabolismo Energético/efectos de los fármacos , Ácidos Linoleicos Conjugados/administración & dosificación , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Tejido Adiposo Pardo/ultraestructura , Animales , Encéfalo/ultraestructura , Suplementos Dietéticos , Aceites de Pescado/administración & dosificación , Expresión Génica/efectos de los fármacos , Hipocampo/ultraestructura , Masculino , Ratones , Ratones Endogámicos C57BL , Mitocondrias Hepáticas/efectos de los fármacos , Mitocondrias Hepáticas/metabolismo , Proteínas Desacopladoras Mitocondriales/genética , Músculo Esquelético/ultraestructura , Consumo de Oxígeno/efectos de los fármacos
14.
Arq Bras Endocrinol Metabol ; 55(5): 303-13, 2011 Jun.
Artículo en Portugués | MEDLINE | ID: mdl-21881812

RESUMEN

The glucose-fatty acid cycle explains the preference for fatty acid during moderate and long duration physical exercise. In contrast, there is a high glucose availability and oxidation rate in response to intense physical exercise. The reactive oxygen species (ROS) production during physical exercise suggests that the redox balance is important to regulate of lipids/carbohydrate metabolism. ROS reduces the activity of the Krebs cycle, and increases the activity of mitochondrial uncoupling proteins. The opposite effects happen during moderate physical activity. Thus, some issues is highlighted in the present review: Why does skeletal muscle prefer lipids in the basal and during moderate physical activity? Why does glucose-fatty acid fail to carry out their effects during intense physical exercise? How skeletal muscles regulate the lipids and carbohydrate metabolism during the contraction-relaxation cycle?


Asunto(s)
Ejercicio Físico/fisiología , Ácidos Grasos/metabolismo , Glucosa/metabolismo , Músculo Esquelético/metabolismo , Animales , Carbohidratos de la Dieta/metabolismo , Humanos , Especies Reactivas de Oxígeno/metabolismo
15.
Arq. bras. endocrinol. metab ; 55(5): 303-313, June 2011. ilus
Artículo en Portugués | LILACS | ID: lil-604159

RESUMEN

O ciclo glicose-ácido graxo explica a preferência do tecido muscular pelos ácidos graxos durante atividade moderada de longa duração. Em contraste, durante o exercício de alta intensidade, há aumento na disponibilidade e na taxa de oxidação de glicose. A produção de espécies reativas de oxigênio (EROs) durante a atividade muscular sugere que o balanço redox intracelular é importante na regulação do metabolismo de lipídios/carboidratos. As EROs diminuem a atividade do ciclo de Krebs e aumentam a atividade da proteína desacopladora mitocondrial. O efeito oposto é esperado durante a atividade moderada. Assim, as questões levantadas nesta revisão são: Por que o músculo esquelético utiliza preferencialmente os lipídios no estado basal e de atividade moderada? Por que o ciclo glicose-ácido graxo falha em exercer seus efeitos durante o exercício intenso? Como o músculo esquelético regula o metabolismo de lipídios e carboidratos em regime envolvendo o ciclo contração-relaxamento.


The glucose-fatty acid cycle explains the preference for fatty acid during moderate and long duration physical exercise. In contrast, there is a high glucose availability and oxidation rate in response to intense physical exercise. The reactive oxygen species (ROS) production during physical exercise suggests that the redox balance is important to regulate of lipids/carbohydrate metabolism. ROS reduces the activity of the Krebs cycle, and increases the activity of mitochondrial uncoupling proteins. The opposite effects happen during moderate physical activity. Thus, some issues is highlighted in the present review: Why does skeletal muscle prefer lipids in the basal and during moderate physical activity? Why does glucose-fatty acid fail to carry out their effects during intense physical exercise? How skeletal muscles regulate the lipids and carbohydrate metabolism during the contraction-relaxation cycle?.


Asunto(s)
Animales , Humanos , Ejercicio Físico/fisiología , Ácidos Grasos/metabolismo , Glucosa/metabolismo , Músculo Esquelético/metabolismo , Carbohidratos de la Dieta/metabolismo , Especies Reactivas de Oxígeno/metabolismo
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