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Fernandez-Galilea M.,University of Navarra | Fernandez-Galilea M.,University of Santiago de Chile | Perez-Matute P.,HIV and Associated Metabolic Alterations Unit | Prieto-Hontoria P.L.,University of Navarra | And 11 more authors.
Biochimica et Biophysica Acta - Molecular and Cell Biology of Lipids | Year: 2015

α-Lipoic acid (α-Lip) is a natural occurring antioxidant with beneficial anti-obesity properties. The aim of this study was to investigate the putative effects of α-Lip on mitochondrial biogenesis and the acquirement of brown-like characteristics by subcutaneous adipocytes fromoverweight/obese subjects. Thus, fully differentiated human subcutaneous adipocyteswere treated with α-Lip (100 and 250 μM) for 24 h for studies on mitochondrial content and morphology, mitochondrial DNA (mtDNA) copy number, fatty acid oxidation enzymes and brown/beige characteristic genes. The involvement of the Sirtuin1/Peroxisome proliferator-activated receptor gamma, coactivator 1 alpha (SIRT1/PGC-1α) pathway was also evaluated. Our results showed that α-Lip increased mitochondrial content in cultured human adipocytes as revealed by electron microscopy and by mitotracker green labeling. Moreover, an enhancement in mtDNA content was observed. This increase was accompanied by an up-regulation of SIRT1 protein levels, a decrease in PGC-1innodataalpha acetylation and up-regulation of Nuclear respiratory factor 1 (Nrf1) and Mitochondrial transcription factor (Tfam) transcription factors. Enhanced oxygen consumption and fatty acid oxidation enzymes, Carnitine palmitoyl transferase 1 and Acyl-coenzyme A oxidase (CPT-1 and ACOX)were also observed. Mitochondria from α-Lip-treated adipocytes exhibited somemorphological characteristics of brown mitochondria, and α-Lip also induced up-regulation of some brown/beige adipocytes markers such as cell death-inducing DFFA-like effector a (Cidea) and T-box 1 (Tbx1). Moreover, α-Lip up-regulated PR domain containing 16 (Prdm16) mRNA levels in treated adipocytes. Therefore, our study suggests the ability of α-Lip to promote mitochondrial biogenesis and brown-like remodeling in cultured white subcutaneous adipocytes from overweight/obese donors. © 2014 Elsevier B.V. All rights reserved.


PubMed | University of the Basque Country, CIBER ISCIII, Cruces University Hospital and BioCruces Health Research Institute, HIV and Associated Metabolic Alterations Unit and 2 more.
Type: Journal Article | Journal: Journal of physiology and biochemistry | Year: 2016

Resveratrol is beneficial in obese and diabetic rodents. However, its low bioavailability raises questions about its therapeutic relevance for treating or preventing obesity complications. In this context, many related natural polyphenols are being tested for their putative antidiabetic and anti-obesity effects. This prompted us to study the influence of piceatannol, a polyhydroxylated stilbene, on the prevention of obesity complications in Zucker obese rats. A 6-week supplementation was followed by the determination of various markers in plasma, liver, adipose tissue and heart, together with a large-scale analysis of gut microbiota composition. When given in doses of 15 or 45mg/kg body weight/day, piceatannol did not reduce either hyperphagia or fat accumulation. It did not modify the profusion of the most abundant phyla in gut, though slight changes were observed in the abundance of several Lactobacillus, Clostridium, and Bacteroides species belonging to Firmicutes and Bacteroidetes. This was accompanied by a tendency to reduce plasma lipopolysaccharides by 30%, and by a decrease of circulating non-esterified fatty acids, LDL-cholesterol, and lactate. While piceatannol tended to improve lipid handling, it did not mitigate hyperinsulinemia and cardiac hypertrophy. However, it increased cardiac expression of ephrin-B1, a membrane protein that contributes to maintaining cardiomyocyte architecture. Lastly, ascorbyl radical plasma levels and hydrogen peroxide release by adipose tissue were similar in control and treated groups. Thus, piceatannol did not exhibit strong slimming capacities but did limit several obesity complications.


PubMed | University Institute of Health Sciences, HIV and Associated Metabolic Alterations Unit, French Institute of Health and Medical Research, University of the Basque Country and CIBER ISCIII
Type: Journal Article | Journal: Journal of physiology and biochemistry | Year: 2016

Obesity-associated nephropathy is considered to be a leading cause of end-stage renal disease. Resveratrol supplementation represents a promising therapy to attenuate kidney injury, but the poor solubility and limited bioavailability of this polyphenol limits its use in dietary intervention. Piceatannol, a resveratrol analogue, has been suggested as a better option. In this study, we aimed to provide evidence of a preventive action of piceatannol in very early stages of obesity-associated nephropathy. Thirty obese Zucker rats were divided into three experimental groups: one control and two groups orally treated for 6weeks with 15 and 45mg piceatannol/kg body weight/day. Enzyme-linked immunosorbent assays (ELISA) were used to determine renal and urinary kidney injury molecule-1 (Kim-1), renal fibrosis markers (transforming growth factor 1 and fibronectin) and renal sirtuin-1 protein. Oxidative stress was assessed in the kidney by measuring lipid peroxidation and nitrosative stress (thiobarbituric acid reactive substrates and 3-nitrotyrosine levels, respectively) together with the activity of the antioxidant enzyme superoxide dismutase. Renal fatty acids profile analysis was performed by thin-layer and gas chromatography. Piceatannol-treated rats displayed lower levels of urinary and renal Kim-1. Renal fibrosis biomarkers and lipid peroxidation exhibited a tendency to decrease in the piceatannol-treated groups. Piceatannol treatment did not modify superoxide dismutase activity or sirtuin-1 protein levels, while it seemed to increase the levels of polyunsaturated and omega-6 polyunsaturated fatty acids in the kidneys. Our findings suggest a mild renoprotective effect of piceatannol in obese Zucker rats and the need of intervention at early stages of renal damage.


Pizarro C.,University of La Rioja | Arenzana-Ramila I.,University of La Rioja | Perez-Del-Notario N.,University of La Rioja | Perez-Matute P.,HIV and Associated Metabolic Alterations Unit | Gonzalez-Saiz J.-M.,University of La Rioja
Analytical Chemistry | Year: 2013

Lipidomics is an emerging field in biomedical research that includes the analysis of all the lipids present in complex biological samples. To evaluate the chemical and biological diversity of lipids, lipid extraction is usually the first step toward lipidomics analysis. Nevertheless, sample preparation is still a time-consuming and error prone analytical step. Therefore, the development of simple and robust methods suitable for high-throughput lipid analysis is of great interest. This study presents a new method for exhaustive lipid fingerprinting of human blood plasma samples based on the employment of methyl tert-butyl ether (MTBE) and ultrasound (US) energy combined with liquid chromatography-electrospray ionization quadrupole-time-of-flight mass spectrometry (LC-ESIqToF-MS). First, the MTBE-US extraction step was optimized by means of experimental design methodology. After the optimization step, a comparative study was performed to assess the suitability of the proposed method. The new method allowed extraction time to be reduced to half, in comparison with previously reported methods. The proposed method also allowed increasing extraction repeatability (with RSDs below 5.55%) and efficiency (recoveries higher than 70% were obtained for all lipids evaluated). Moreover, the new proposed method enables more than 800 different features to be detected. Thus, the overall number of lipids identified with the databases for this novel extraction method (352) was the highest of the evaluated methods. The efficiency, precision, and feature detection capacity of the proposed method confirmed its suitability for the evaluation of the lipid profile of human blood plasma samples. Moreover, taking into account its simplicity, low time consumption, and compatibility with automation, the new proposed method could be a suitable alternative to previously reported methods for use in laboratories for comprehensive lipidomic profiling. © 2013 American Chemical Society.


Valdecantos M.P.,University of Navarra | Perez-Matute P.,HIV and Associated Metabolic Alterations Unit | Gonzalez-Muniesa P.,University of Navarra | Prieto-Hontoria P.L.,University of Navarra | And 2 more authors.
Obesity | Year: 2012

Nonalcoholic steatosis is an important hepatic complication of obesity linked to mitochondrial dysfunction and oxidative stress. Lipoic acid (LA) has been reported to have beneficial effects on mitochondrial function and to attenuate oxidative stress. The sirtuin (SIRT) family has been demonstrated to play an important role in the regulation of mitochondrial function and in the activation of antioxidant defenses. In this study, we analyzed the potential protective effect of LA supplementation, via the modulation of mitochondrial defenses through the SIRT pathway, against oxidative stress associated with high-fat feeding. Wistar rats were fed a standard diet (control group (C), n = 10), a high-fat diet (obese group (OB), n = 10) and a high-fat diet supplemented with LA (OLIP, n = 10). A group pair-fed to the latter group (pair-fed OLIP group (PFO), n = 6) was also included. LA prevented hepatic triglyceride (TG) accumulation (68.2%) and liver oxidative damage (P < 0.01) through the inhibition of hydroperoxide (H2O2) production (P < 0.001) and the stimulation of mitochondrial antioxidant defenses. LA treatment upregulated manganese superoxide dismutase (SOD2) (60.6%) and glutathione peroxidase (GPx) (100.2%) activities, and increased the reduced glutathione (GSH): oxidized glutathione (GSSG) ratio and UCP2 mRNA levels (P < 0.001-P < 0.01). Moreover, this molecule reduced oxidative damage in mitochondrial DNA (mtDNA) and increased mitochondrial copy number (P < 0.001- P < 0.01). LA treatment decreased the acetylation levels of Forkhead transcription factor 3a (Foxo3a) and PGC1Β (P < 0.001- P < 0.01) through the stimulation of SIRT3 and SIRT1 (P < 0.001). In summary, our results demonstrate that the beneficial effects of LA supplementation on hepatic steatosis could be mediated by its ability to restore the oxidative balance by increasing antioxidant defenses through the deacetylation of Foxo3a and PGC1Β by SIRT1 and SIRT3.


Prieto-Hontoria P.L.,University of Navarra | Perez-Matute P.,University of Navarra | Perez-Matute P.,HIV and Associated Metabolic Alterations Unit | Fernandez-Galilea M.,University of Navarra | And 2 more authors.
European Journal of Nutrition | Year: 2013

Background: Lipoic acid (LA) is an antioxidant with antiobesity and antidiabetic properties. Adiponectin is an adipokine with potent anti-inflammatory and insulin-sensitizing properties. AMP-activated protein kinase (AMPK) is a key enzyme involved in cellular energy homeostasis. Activation of AMPK has been considered as a target to reverse the metabolic abnormalities associated with obesity and type 2 diabetes. Aim of the study: The aim of this study was to determine the effects of LA on AMPK phosphorylation and adiponectin production in adipose tissue of low-fat (control diet) and high-fat diet-fed rats. Results: Dietary supplementation with LA reduced body weight and adiposity in control and high-fat-fed rats. LA also reduced basal hyperinsulinemia as well as the homeostasis model assessment (HOMA) levels, an index of insulin resistance, in high-fat-fed rats, which was in part independent of their food intake lowering actions. Furthermore, AMPK phosphorylation was increased in white adipose tissue (WAT) from LA-treated rats as compared with pair-fed animals. Dietary supplementation with LA also upregulated adiponectin gene expression in WAT, while a negative correlation between adiposity-corrected adiponectin levels and HOMA index was found. Our present data suggest that the ability of LA supplementation to prevent insulin resistance in high-fat diet-fed rats might be related in part to the stimulation of AMPK and adiponectin in WAT. © 2012 Springer-Verlag.


Villanueva-Millan M.J.,HIV and Associated Metabolic Alterations Unit | Perez-Matute P.,HIV and Associated Metabolic Alterations Unit | Oteo J.A.,HIV and Associated Metabolic Alterations Unit | Oteo J.A.,Hospital San Pedro
Journal of Physiology and Biochemistry | Year: 2015

Gut microbiota, its evolutive dynamics and influence on host through its protective, trophic and metabolic actions, has a key role in health and opens unique opportunities for the identification of new markers of the physiopathological state of each individual. Alterations in gut microbiota composition have been associated with plenty disorders. Of interest, the vast number of studies demonstrates the role of microbiota in obesity, a serious public health problem that has reached epidemic proportions in many developed and middle-income countries. The economic and health costs of this condition and its comorbidities such as fatty liver, insulin resistance/diabetes, or cardiovascular events are considerable. Therefore, every strategy designed to reduce obesity would imply important savings. Targeting microbiota, in order to restore/modulate the microbiota composition with antibiotics, probiotics, prebiotics, or even fecal transplants, is considered as a promising strategy for the development of new solutions for the treatment of obesity. However, there is still lot to do in this field in order to identify the exact composition of microbiota in “health” and the specific mechanisms that regulate the host-microbiotal crosstalk. In addition, it is important to note that changes not only in the gut microbiota profile (abundance) but also in its metabolism and functions need to be taken into account in the context of contribution in the physiopathology of obesity and related disorders. © 2015, University of Navarra.


Fernandez-Galilea M.,University of Navarra | Perez-Matute P.,University of Navarra | Perez-Matute P.,HIV and Associated Metabolic Alterations Unit | Prieto-Hontoria P.L.,University of Navarra | And 2 more authors.
Journal of Lipid Research | Year: 2012

Lipoic acid (LA) is a naturally occurring compound with beneficial effects on obesity. The aim of this study was to evaluate its effects on lipolysis in 3T3-L1 adipocytes and the mechanisms involved. Our results revealed that LA induced a dose- and time-dependent lipolytic action, which was reversed by pretreatment with the c-Jun N-terminal kinase inhibitor SP600125, the PKA inhibitor H89, and the AMP-activated protein kinase activator AICAR. In contrast, the PI3K/Akt inhibitor LY294002 and the PDE3B antagonist cilostamide enhanced LA-induced lipolysis. LA treatment for 1 h did not modify total protein content of hormone-sensitive lipase (HSL) but significantly increased the phosphorylation of HSL at Ser563 and at Ser660, which was reversed by H89. LA treatment also induced a marked increase in PKA-mediated perilipin phosphorylation. LA did not significantly modify the protein levels of adipose triglyceride lipase or its activator comparative gene identification 58 (CGI-58) and inhibitor G(0)/G(1) switch gene 2 (G0S2). Furthermore, LA caused a significant inhibition of adiposespecific phospholipase A2 (AdPLA) protein and mRNA levels in parallel with a decrease in the amount of prostaglandin E 2 released and an increase in cAMP content. Together, these data suggest that the lipolytic actions of LA are mainly mediated by phosphorylation of HSL through cAMP-mediated activation of protein kinase A probably through the inhibition of AdPLA and prostaglandin E2. Copyright © 2012 by the American Society for Biochemistry and Molecular Biology, Inc.


Prieto-Hontoria P.L.,University of Navarra | Perez-Matute P.,University of Navarra | Perez-Matute P.,HIV and Associated Metabolic Alterations Unit | Fernandez-Galilea M.,University of Navarra | And 2 more authors.
Molecular Nutrition and Food Research | Year: 2011

Scope: Lipoic acid (LA) is an antioxidant with therapeutic potential on several diseases such as diabetes and obesity. Hyperleptinemia and oxidative stress play a major role in the development of obesity-linked diseases. The aim of this study was to examine in vivo and in vitro the effects of LA on leptin production, as well as to elucidate the mechanisms and signalling pathways involved in LA actions. Methods and results: Dietary supplementation with LA decreased both circulating leptin, and adipose tissue leptin mRNA in rats. Treatment of 3T3-L1 adipocytes with LA caused a concentration-dependent inhibition of leptin secretion and gene expression. Moreover, LA stimulated the anaerobic utilization of glucose to lactate, which negatively correlated with leptin secretion. Furthermore, LA enhanced phosphorylation of Sp1 and inhibited Sp1 transcriptional activity in 3T3-L1 adipocytes. Moreover, LA inhibited Akt phosphorylation, a downstream target of phosphatidylinositol 3-kinase (PI3K). Treatment with the PI3K inhibitor LY294002 mimicked LA actions, dramatically inhibiting both leptin secretion and gene expression and stimulating Sp1 phosphorylation. Conclusion: All of these data suggest that the phosphorylation of Sp1 and the accompanying reduced DNA-binding activity are likely to be involved in the inhibition of leptin induced by LA, which could be mediated in part by the abrogation of the PI3K/Akt pathway. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Perez-Matute P.,HIV and Associated Metabolic Alterations Unit | Perez-Martinez L.,HIV and Associated Metabolic Alterations Unit | Blanco J.R.,HIV and Associated Metabolic Alterations Unit | Blanco J.R.,Hospital San Pedro | And 2 more authors.
Current HIV Research | Year: 2011

Raltegravir (RAL) has been shown to be virologically effective in both treatment naive and triple class resistant patients. A more favourable metabolic profile associated with RAL in comparison with other antiretroviral drugs has also been observed. The aim of this study was to investigate the molecular mechanisms that could explain the lack of toxicity of this drug in metabolism. Thus, the effects of RAL on adipogenesis and adipocyte metabolism were analyzed using 3T3- L1 cells, a very adequate and convenient cell culture model for the investigation of adipose differentiation and metabolism. The effects of RAL on adipogenesis were evaluated by the Oil Red O staining after 8 days of induction of differentiation. Several adipogenic genes (C/EBPα, PPARβ, Pref-1 and AP2) were analyzed by Real-Time PCR. Fully differentiated adipocytes were also incubated with RAL for 24 hours and glucose utilization, lactate production and glycerol release were analyzed. Thus, minimal effects of RAL on murine adipocyte differentiation were observed. Basal glucose uptake and lactate production were not affected by RAL at any of the concentrations used. No effects were also found on the percentage of glucose that is metabolized to lactate. Lipolysis was only slightly inhibited by Raltegravir (-10%) at the highest concentration used (50 μM), while no effects were observed with lower doses. Our results suggest that the absence of significant actions of RAL on adipogenesis and glucose and lipid metabolism in adipocytes could explain, at least in part, the neutral metabolic effects of RAL in clinical studies. © 2011 Bentham Science Publishers Ltd.

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