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Hepatic fat-specific protein 27 [cell death-inducing DNA fragmentation effector protein C (Cidec)/Fsp27] mRNA levels have been associated with hepatic lipid droplet extent under certain circumstances. To address its hepatic expression under different dietary conditions and in both sexes, apolipoprotein E (Apoe)-deficient mice were subjected to different experimental conditions for 11 wk to test the influence of cholesterol, Western diet, squalene, oleanolic acid, sex, and surgical castration on Cidec/Fsp27 mRNA expression. Dietary cholesterol increased hepatic Cidec/Fsp27β expression, an effect that was suppressed when cholesterol was combined with saturated fat as represented by Western diet feeding. Using the latter diet, neither oleanolic acid nor squalene modified its expression. Females showed lower levels of hepatic Cidec/Fsp27β expression than males when they were fed Western diets, a result that was translated into a lesser amount of CIDEC/FSP27 protein in lipid droplets and microsomes. This was also confirmed in low-density lipoprotein receptor (Ldlr)-deficient mice. Incubation with estradiol resulted in decreased Cidec/Fsp27β expression in AML12 cells. Whereas male surgical castration did not modify the expression, ovariectomized females did show increased levels compared with control females. Females also showed increased expression of peroxisome proliferator-activated receptor-γ coactivator 1-α (Pgc1a), suppressed by ovariectomy, and the values were significantly and inversely associated with those of Cidec/Fsp27β. When Pgc1a-deficient mice were used, the sex differences in Cidec/Fsp27β expression disappeared. Therefore, hepatic Cidec/Fsp27β expression has a complex regulation influenced by diet and sex hormonal milieu. The mRNA sex differences are controlled by Pgc1a., This research was supported by Ministerio de Economía y CompetitividadFondo Europeo de Desarrollo Regional (Grants SAF2015-63904-R, SAF2016-75441-R, and RTI2018-093864-B-I00), Fondo Social Europeo-Gobierno de Aragón (Grant B16_17R), and the European Union’s Horizon 2020 research and innovation program under Marie Skłodowska-Curie Grant Agreement 721236-TREATMENT to M. Monsalve. Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y Nutrición (CB06/03/1012) is an initiative of Instituto de Salud Carlos III. L. V. Herrera-Marcos and S. Sancho-Knapik were recipients of Fondo Social Europeo-Gobierno de Aragón and Fundación Cuenca-Villoro (BE 203/2009) fellowships, respectively.

© 2021 by the authors., Mitophagy is a selective autophagic process, essential for cellular homeostasis, that eliminates dysfunctional mitochondria. Activated by inner membrane depolarization, it plays an important role during development and is fundamental in highly differentiated post-mitotic cells that are highly dependent on aerobic metabolism, such as neurons, muscle cells, and hepatocytes. Both defective and excessive mitophagy have been proposed to contribute to age-related neurodegenerative diseases, such as Parkinson’s and Alzheimer’s diseases, metabolic diseases, vascular complications of diabetes, myocardial injury, muscle dystrophy, and liver disease, among others. Pharmacological or dietary interventions that restore mitophagy homeostasis and facilitate the elimination of irreversibly damaged mitochondria, thus, could serve as potential therapies in several chronic diseases. However, despite extraordinary advances in this field, mainly derived from in vitro and preclinical animal models, human applications based on the regulation of mitochondrial quality in patients have not yet been approved. In this review, we summarize the key selective mitochondrial autophagy pathways and their role in prevalent chronic human diseases and highlight the potential use of specific interventions., This research was funded by the Spanish “Ministerio de Ciencia, Innovación y Universidades” (MICIU) and ERDF/FEDER funds, grant number RTI2018-093864-B-I00, and the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement 721236-TREATMENT to M.M.

Metabolic plasticity is the ability of a biological system to adapt its metabolic phenotype to different environmental stressors. We used a whole-body and tissue-specific phenotypic, functional, metabolomic and transcriptomic approach to systematically assess metabolic plasticity in diet-induced obese mice after a combined nutritional and exercise intervention. Although most pathological features were successfully reverted, we observed a high degree of metabolic dysfunction irreversibility in visceral white adipose tissue, characterised by abnormal mitochondrial morphology and functionality. Despite two sequential therapeutic interventions and apparent global phenotypic recovery, obesity specifically triggered in visceral adipose a cascade of events progressing from mitochondrial metabolic and proteostatic defects to widespread cellular stress, which compromises its biosynthetic and recycling capacity. Our data indicate that obesity prompts a lasting metabolic fingerprint that leads to a progressive breakdown of metabolic plasticity in white adipose tissue, becoming a significant milestone in disease progression.

Reactive Oxygen Species (ROS) are key mediators of ischemia-reperfusion injury but also required for the induction of the stress response that limits tissue injury and underlies the protection provided by ischemic-preconditioning protocols. Liver steatosis is an important risk factor for liver transplant failure. Liver steatosis is associated with mitochondrial dysfunction and excessive mitochondrial ROS production. Studies aiming at decreasing the sensibility of the steatotic liver to ischemia-reperfusion injury using pre-conditioning protocols, have shown that the steatotic liver has a reduced capacity to respond to these protocols. Recent studies indicate that these effects are related to a reduced capacity of the steatotic liver to respond to elevated ROS levels following reperfusion by inducing a compensatory response. This failure to respond to ROS is associated with reduced levels of antioxidants, mitochondrial damage, hepatocyte cell death, activation of the immune system and induction of pro-fibrotic mediators., This work was supported by grants from the Spanish ‘‘Ministerio de Economía y Competitividad’’ (Grant numbers SAF2015-63904-R and SAF2015-71521-REDC).

This article belongs to the Special Issue Molecular Mechanisms of Kidney Injury and Repair., Chronic kidney disease (CKD) is one of the fastest growing causes of death worldwide, emphasizing the need to develop novel therapeutic approaches. CKD predisposes to acute kidney injury (AKI) and AKI favors CKD progression. Mitochondrial derangements are common features of both AKI and CKD and mitochondria-targeting therapies are under study as nephroprotective agents. PGC-1α is a master regulator of mitochondrial biogenesis and an attractive therapeutic target. Low PGC-1α levels and decreased transcription of its gene targets have been observed in both preclinical AKI (nephrotoxic, endotoxemia, and ischemia-reperfusion) and in experimental and human CKD, most notably diabetic nephropathy. In mice, PGC-1α deficiency was associated with subclinical CKD and predisposition to AKI while PGC-1α overexpression in tubular cells protected from AKI of diverse causes. Several therapeutic strategies may increase kidney PGC-1α activity and have been successfully tested in animal models. These include AMP-activated protein kinase (AMPK) activators, phosphodiesterase (PDE) inhibitors, and anti-TWEAK antibodies. In conclusion, low PGC-1α activity appears to be a common feature of AKI and CKD and recent characterization of nephroprotective approaches that increase PGC-1α activity may pave the way for nephroprotective strategies potentially effective in both AKI and CKD., Supported by ISCIII-FIS, FEDER funds, CP14/00133, PI16/02057, PI16/01900, PI18/01366, PI19/00588, PI19/00815, DTS18/00032, ERA-PerMed-JTC2018 (KIDNEY ATTACK AC18/00064 and PERSTIGAN AC18/00071, ISCIII-RETIC REDinREN RD016/0009, Sociedad Española de Nefrología, Fundacion Renal IñigoÁlvarez de Toledo (FRIAT), ISCIII Miguel Servet (A.B.S., M.D.S.-N.), ISCIII Sara Borrell (J.M.M.-M.), Comunidad de Madrid CIFRA2 B2017/BMD-3686 (M.F.-B. and D.M.-S.).

Acute pancreatitis is an inflammatory process of the pancreatic tissue that often leads to distant organ dysfunction. Although liver injury is uncommon in acute pancreatitis, obesity is a risk factor for the development of hepatic complications. The aim of this work was to evaluate the role of PGC-1&alpha, in inflammatory response regulation in the liver and its contribution to the detrimental effect of obesity on the liver during acute pancreatitis. For this purpose, we induced acute pancreatitis by cerulein in not only wild-type (WT) and PGC-1&alpha, knockout (KO) mice, but also in lean and obese mice. PGC-1&alpha, levels were up-regulated in the mice livers with pancreatitis. The increased PGC-1&alpha, levels were bound to p65 to restrain its transcriptional activity toward Nos2. Lack of PGC-1&alpha, favored the assembly of the p65/phospho-STAT3 complex, which promoted Nos2 expression during acute pancreatitis. The increased transcript Nos2 levels and the pro-oxidant liver status caused by the down-regulated expression of the PGC-1&alpha, dependent antioxidant genes enhanced nitrosative stress and decreased energy charge in the livers of the PGC-1&alpha, KO mice with pancreatitis. It is noteworthy that the PGC-1&alpha, levels lowered in the obese mice livers, which increased the Nos2 mRNA expression and protein nitration levels and decreased energy charge during pancreatitis. In conclusion, obesity impairs PGC-1&alpha, up-regulation in the liver to cause nitrosative stress during acute pancreatitis.

© 2020 by the authors., Cancer is one of the highest prevalent diseases in humans. The chances of surviving cancer and its prognosis are very dependent on the affected tissue, body location, and stage at which the disease is diagnosed. Researchers and pharmaceutical companies worldwide are pursuing many attempts to look for compounds to treat this malignancy. Most of the current strategies to fight cancer implicate the use of compounds acting on DNA damage checkpoints, non-receptor tyrosine kinases activities, regulators of the hedgehog signaling pathways, and metabolic adaptations placed in cancer. In the last decade, the finding of a lipid peroxidation increase linked to 15-lipoxygenases isoform 1 (15-LOX-1) activity stimulation has been found in specific successful treatments against cancer. This discovery contrasts with the production of other lipid oxidation signatures generated by stimulation of other lipoxygenases such as 5-LOX and 12-LOX, and cyclooxygenase (COX-2) activities, which have been suggested as cancer biomarkers and which inhibitors present anti-tumoral and antiproliferative activities. These findings support the previously proposed role of lipid hydroperoxides and their metabolites as cancer cell mediators. Depletion or promotion of lipid peroxidation is generally related to a specific production source associated with a cancer stage or tissue in which cancer originates. This review highlights the potential therapeutical use of chemical derivatives to stimulate or block specific cellular routes to generate lipid hydroperoxides to treat this disease., This research was funded by Ministerio de Ciencia e Innovación grant number RTI2018-093864-B-I00 and the European Union’s Horizon 2020 Research and Innovation Programme MSCA GA 721236-TREATMENT.

PGC-1α controls, to a large extent, the capacity of cells to respond to changing nutritional requirements and energetic demands. The key role of metabolic reprogramming in tumor development has highlighted the potential role of PGC-1α in cancer. To investigate how loss of PGC-1α activity in primary cells impacts the oncogenic characteristics of spontaneously immortalized cells, and the mechanisms involved, we used the classic 3T3 protocol to generate spontaneously immortalized mouse embryonic fibroblasts (iMEFs) from wild-type (WT) and PGC-1α knockout (KO) mice and analyzed their oncogenic potential in vivo and in vitro. We found that PGC-1α KO iMEFs formed larger and more proliferative primary tumors than WT counterparts, and fostered the formation of lung metastasis by B16 melanoma cells. These characteristics were associated with the reduced capacity of KO iMEFs to respond to cell contact inhibition, in addition to an increased ability to form colonies in soft agar, an enhanced migratory capacity, and a reduced growth factor dependence. The mechanistic basis of this phenotype is likely associated with the observed higher levels of nuclear β-catenin and c-myc in KO iMEFs. Evaluation of the metabolic adaptations of the immortalized cell lines identified a decrease in oxidative metabolism and an increase in glycolytic flux in KO iMEFs, which were also more dependent on glutamine for their survival. Furthermore, glucose oxidation and tricarboxylic acid cycle forward flux were reduced in KO iMEF, resulting in the induction of compensatory anaplerotic pathways. Indeed, analysis of amino acid and lipid patterns supported the efficient use of tricarboxylic acid cycle intermediates to synthesize lipids and proteins to support elevated cell growth rates. All these characteristics have been observed in aggressive tumors and support a tumor suppressor role for PGC-1α, restraining metabolic adaptations in cancer., This work was funded by grants from the Spanish “Ministerio de Ciencia, Innovación y Universidades” (MICINN) and ERDF/FEDER funds, SAF2012-37693, SAF2015-63904-R, SAF2015-71521-REDC, RTI2018-093864-B-I00 to M.M., SAF2017-83043-R and B2017/BMD-3724 to S·C., PI15/00107 to A.M.R, the University of the Basque Country UPV/EHU grant GIU16/62) to J.l.R.S. and M.B.R.L., and the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement 721236-TREATMENT to M.M.

Most pharmacological studies concerning the beneficial effects of organoselenium compounds have focused on their ability to mimic glutathione peroxidase (GPx). However, mechanisms other than GPx-like activity might be involved on their biological effects. This study was aimed to investigate and compare the protective effects of two well known [(PhSe)2 and PhSeZnCl] and two newly developed (MRK Picolyl and MRK Ester) organoselenium compounds against oxidative challenge in cultured neuronal HT22 cells. The thiol peroxidase and oxidase activities were performed using the glutathione reductase (GR)-coupled assay. In order to evaluate protective effects of the organoselenium compounds against oxidative challenge in neuronal HT22 cells, experiments based on glutamate-induced oxytosis and SIN-1-mediated peroxynitrite generation were performed. The thiol peroxidase activities of the studied organoselenium compounds were smaller than bovine erythrocytes GPx enzyme. Besides, (PhSe)2 and PhSeZnCl showed higher thiol peroxidase and lower thiol oxidase activities compared to the new compounds. MRK Picolyl and MRK Ester, which showed lower thiol peroxidase activity, showed higher thiol oxidase activity. Both pre- or co-treatment with (PhSe)2, PhSeZnCl, MRK Picolyl and MRK Ester protected HT22 cells against glutamate-induced cytotoxicity. (PhSe)2 and MRK Picolyl significantly prevented peroxinitrite-induced dihydrorhodamine oxidation, but this effect was observed only when HT22 were pre-treated with these compounds. The treatment with (PhSe)2 increased the protein expression of antioxidant defences (Prx3, CAT and GCLC) in HT22 cells. Taking together, our results suggest that the biological effects elicited by these compounds are not directly related to their GPx-mimetic and thiol oxidase activities, but might be linked to the up-regulation of endogenous antioxidant defences trough their thiol-modifier effects., The funding was provided by Conselho Nacional de Desenvolvimento Científico e Tecnológico (Grant Nos. 401065/204-6 and 424809/2018-4) and FAPDF (Grant No. 712/2019). L.G.S. was recipient of a PhD fellowship from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).

MicroRNAs (miRNAs) regulate gene expression posttranscriptionally and control biological processes (BPs), including fibrogenesis. Kidney fibrosis remains a clinical challenge and miRNAs may represent a valid therapeutic avenue. We show that miR‐9‐5p protected from renal fibrosis in the mouse model of unilateral ureteral obstruction (UUO). This was reflected in reduced expression of pro‐fibrotic markers, decreased number of infiltrating monocytes/macrophages, and diminished tubular epithelial cell injury and transforming growth factor‐beta 1 (TGF‐β1)‐dependent de‐differentiation in human kidney proximal tubular (HKC‐8) cells. RNA‐sequencing (RNA‐Seq) studies in the UUO model revealed that treatment with miR‐9‐5p prevented the downregulation of genes related to key metabolic pathways, including mitochondrial function, oxidative phosphorylation (OXPHOS), fatty acid oxidation (FAO), and glycolysis. Studies in human tubular epithelial cells demonstrated that miR‐9‐5p impeded TGF‐β1‐induced bioenergetics derangement. The expression of the FAO‐related axis peroxisome proliferator‐activated receptor gamma coactivator 1 alpha (PGC‐1α)‐peroxisome proliferator‐activated receptor alpha (PPARα) was reduced by UUO, although preserved by the administration of miR‐9‐5p. We found that in mice null for the mitochondrial master regulator PGC‐1α, miR‐9‐5p was unable to promote a protective effect in the UUO model. We propose that miR‐9‐5p elicits a protective response to chronic kidney injury and renal fibrosis by inducing reprogramming of the metabolic derangement and mitochondrial dysfunction affecting tubular epithelial cells., This work was supported by Grants from the Ministerio de Economía y Competitividad (MINECO) SAF 2012‐31388 (SL) and SAF2015‐66107‐R (SL), both cofunded by the European Regional Development Fund, Instituto de Salud Carlos III REDinREN RD12/0021/0009 and RD16/0009/0016 (SL and MRO), PI17/00119 (MRO), SAF2015‐63904‐R (MM), cofunded by the European Regional Development Fund, European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska‐Curie grant agreement 721236‐TREATMENT (MM), Comunidad de Madrid “NOVELREN” B2017/BMD­3751 (SL and MRO), and Fundación Renal “Iñigo Alvarez de Toledo” (SL), all from Spain. The CBMSO receives institutional support from Fundación “Ramón Areces”. VM and CNT were supported by predoctoral fellowships of the FPI Program (BES‐2013‐065986 and BES‐2014‐068929) from MINECO.

This article belongs to the Special Issue Cellular Stress Response in Health and Disease., The interplay of mitochondria with the endoplasmic reticulum and their connections, called mitochondria-ER contacts (MERCs) or mitochondria-associated ER membranes (MAMs), are crucial hubs in cellular stress. These sites are essential for the passage of calcium ions, reactive oxygen species delivery, the sorting of lipids in whole-body metabolism. In this perspective article, we focus on microscopic evidences of the pivotal role of MERCs/MAMs and their changes in metabolic diseases, like obesity, diabetes, and neurodegeneration., This research was funded by FFARB 2017 of A.S., ex 60% grants of University of Brescia (Italy) of A.S. and R.R. and Spanish “Ministerio de Economía Industria y Competitividad” (MINEICO) that includes FEDER funds (SAF2015-63904-R) and from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie agreement 721236-TREATMENT of M.M.

[Aims]: Oxidative stress is known to induce early replicative senescence. Senescence has been proposed to work as a barrier to immortalization and tumor development. Here, we aimed to evaluate the impact of the loss of peroxisome proliferator activated receptor γ co-activator 1α (PGC-1α), a master regulator of oxidative metabolism and mitochondrial reactive oxygen species (ROS) generation, on replicative senescence and immortalization in mouse embryonic fibroblasts (MEFs)., [Results]: We found that primary MEFs lacking PGC-1α showed higher levels of ROS than wild-type MEFs at all cell passages tested. The elevated production of ROS was associated with higher levels of oxidative DNA damage and the increased formation of DNA double-strand breaks. Evaluation of the induction of DNA repair systems in response to γ-radiation indicated that the loss of PGC-1α also resulted in a small but significant reduction in their activity. DNA damage induced the early activation of senescence markers, including an increase in the number of β-galactosidase-positive cells, the induction of p53 phosphorylation, and the increase in p16 and p19 protein. These changes were, however, not sufficient to reduce proliferation rates of PGC-1α-deficient MEFs at any cell passage tested. Moreover, PGC-1α-deficient cells escaped replicative senescence., [Innovation & conclusion]: PGC-1α plays an important role in the control of cellular senescence and immortalization., This work was supported by grants from the Spanish Ministerio de Economía Industria y Competitividad (MINEICO) and FEDER funds [Grant numbers SAF2012-37693, SAF2015-63904-R, SAF2015-71521-REDC, to M.M., BFU-2014-53610-P to A.A.], from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Action grant agreement 721236-TREATMENT to M.M. and MPY-1038/14 and MPY-1146/16 from ISCIII to A.Z.

Capítulo 6, Parte I: Biochemical and Molecular Methods., All four FOXO isoforms have been shown to respond to changes in the cellular redox status of the cell, and regulate the expression of target genes that in turn can modulate the cellular oxidative status. However, the mechanisms involved are still controversial. It is clear though that redox regulation of FOXO factors occurs at different levels. The proteins themselves are redox-sensitive and their capacity to bind their target sites seems to be at least partially dependent on their oxidative status. Importantly, several of the cofactors that are known to regulate FOXO transcriptional activity are also sensitive to changes in the cellular redox status, in particular the deacetylase SirT1 is activated in response to reduced levels of reducing equivalents (increased NAD+/NADH+ ratio) and the coactivator PGC-1α is induced in response to increased cellular oxidative stress. Furthermore, nuclear localization of FOXO factors is also regulated by proteins that, like AKT, are themselves regulated directly or indirectly by the cellular levels of reactive oxygen and nitrogen species. In this technical review, we aim to update the current status of our knowledge of how to handle redox-regulated FOXO factor research in order to better understand FOXO biology., This work was supported by grants from the Spanish “Ministerio de Economía Industria y Competitividad” (MINEICO) and FEDER funds [Grant numbers SAF2015-63904-R, SAF2015-71521-REDC] and from the EU H2020 framework programm Grant MSCA-ITN-2016-721236.

Taurine (TAU) is a sulfur-containing beta amino acid that is not involved in protein composition and anabolism, conditionally essential in mammals provided through diet. Growing evidence supports a protective role of TAU supply in osmoregulation, calcium flux, and reduction of inflammation and oxidant damage in renal diseases like diabetes. Endoplasmic reticulum (ER) stress, due to abnormal proteostasis, is a contributor to nephrotic syndrome and related renal damage. Here, we investigated the effect of dietary TAU (1.5% in drinking water for 15 days) in an established rat model that mimics human minimal change nephrosis, consisting of a single puromycin aminonucleoside (PAN) injection (intraperitoneally 15 mg/100 g body weight), with sacrifice after eight days. TAU limited proteinuria and podocytes foot processes effacement, and balanced slit diaphragm nephrin and glomerular claudin 1 expressions. In cortical proximal tubules, TAU improved lysosomal density, ER perimeter, restored proper ER-mitochondria tethering and mitochondrial cristae, and decreased inflammation. Remarkably, TAU downregulated glomerular ER stress markers (GRP78, GRP94), pro-apoptotic C/EBP homologous protein, activated caspase 3, tubular caspase1, and mitochondrial chaperone GRP75, but maintained anti-apoptotic HSP25. In conclusion, TAU, by targeting upstream ER stress separate from mitochondria dysfunctions at crucial renal sites, might be a promising dietary supplement in the treatment of the drug-resistant nephrotic syndrome., This study was supported by New Pet Food Italia S.r.l. (Italy) donation, ex 60% grants from the University of Brescia (Italy), FFARB 2017, SAF2015-63904-R grant from the Spanish Ministerio de Economía Industria y Competitividad (MINEICO), FEDER funds and MSCA-ITN-2016-721236 from the European Commission H2020-MSCA-ITN program.

Peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α) is a regulator of mitochondrial oxidative metabolism and reactive oxygen species (ROS) homeostasis that is known to be inactivated in diabetic subjects. This study aimed to investigate the contribution of PGC-1α inactivation to the development of oxygen-induced retinopathy. We analyzed retinal vascular development in PGC-1α mice. Retinal vasculature of PGC-1α mice showed reduced pericyte coverage, a de-structured vascular plexus, and low perfusion. Exposure of PGC-1α mice to hyperoxia during retinal vascular development exacerbated these vascular abnormalities, with extensive retinal hemorrhaging and highly unstructured areas as compared with wild-type mice. Structural analysis demonstrated a reduction in membrane-bound VE-cadherin, which was suggestive of defective intercellular junctions. Interestingly, PGC-1α retinas showed a constitutive activation of the VEGF-A signaling pathway. This phenotype could be partially reversed by antioxidant administration, indicating that elevated production of ROS in the absence of PGC-1α could be a relevant factor in the alteration of the VEGF-A signaling pathway. Collectively, our findings suggest that PGC-1α control of ROS homeostasis plays an important role in the regulation of de novo angiogenesis and is required for vascular stability., This work was supported by grants from the Spanish ‘‘Ministerio de Economía y Competitividad’’ (Grant number SAF2009-07599 & SAF2012-37693 to M.M and CSD 2007-00020 to M.M.) and the ‘‘Comunidad de Madrid’’ (Grant Number S2010/BMD-2361 to M.M.).

et al., [Objective]: Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) is a transcriptional coactivator that has been proposed to play a protective role in mouse models of cardiac ischemia and heart failure, suggesting that PGC-1α could be relevant as a prognostic marker. Our previous studies showed that the estimation of peripheral mRNA PGC-1α expression was feasible and that its induction correlated with the extent of myocardial necrosis and left ventricular remodeling in patients with myocardial infarction. In this study, we sought to determine if the myocardial and peripheral expressions of PGC-1α are well correlated and to analyze the variability of PGC-1α expression depending on the prevalence of some metabolic disorders. [Methods]: This was a cohort of 35 consecutive stable heart failure patients with severe aortic stenosis who underwent an elective aortic valve replacement surgery. mRNA PGC-1α expression was simultaneously determined from myocardial biopsy specimens and blood samples obtained during surgery by quantitative PCR, and a correlation between samples was made using the Kappa index. Patients were divided into two groups according to the detection of baseline expression levels of PGC-1α in blood samples, and comparisons between both groups were made by chi-square test or unpaired Student’s t-test as appropriate. [Results]: Based on myocardial biopsies, we found that mRNA PGC-1α expression in blood samples showed a statistically significant correlation with myocardial expression (Kappa index 0.66, p, Grant from Sociedad Valenciana de Cardiología, 2013 to Óscar Fabregat-Andrés.

et al., [ES]: [Introduction and objectives]: Peroxisome proliferator-activated receptor gamma coactivator 1a (PGC-1a) is a metabolic regulator induced during ischemia that prevents cardiac remodeling in animal models. The activity of PGC-1a can be estimated in patients with ST-segment elevation acute myocardial infarction. The aim of the present study was to evaluate the value of plasma PGC-1a levels in predicting the extent of necrosis and ventricular remodeling after infarction. [Methods]: In this prospective study of 31 patients with a first myocardial infarction in an anterior location and successful reperfusion, PGC-1a expression in peripheral blood on admission and at 72 hours was correlated with myocardial injury, ventricular volume, and systolic function at 6 months. Edema and myocardial necrosis were estimated using cardiac magnetic resonance imaging during thefirst week. At 6 months, infarct size and ventricular remodeling, defined as an increase > 10% of the left ventricular end-diastolic volume, was evaluated by follow-up magnetic resonance imaging. Myocardial salvage was defined as the difference between the edema and necrosis areas. [Results]: Greater myocardial salvage was seen in patients with detectable PGC-1a levels at admission (mean [standard deviation (SD)], 18.3% [5.3%] vs 4.5% [3.9%]; P = .04). Induction of PGC-1a at 72 hours correlated with greater ventricular remodeling (change in left ventricular end-diastolic volume at 6 months, 29.7% [11.2%] vs 1.2% [5.8%]; P = .04). Conclusions: Baseline PGC-1a expression and an attenuated systemic response after acute myocardial infarction are associated with greater myocardial salvage and predict less ventricular remodeling., [EN]: [Introducción y objetivos]: El coactivador 1a del receptor activado gamma del proliferador de peroxisoma (PGC-1a) es un regulador metabólico que se induce durante la isquemia y previene el remodelado cardiaco en modelos animales. Su actividad puede estimarse en pacientes con infarto agudo de miocardio con elevación del segmento ST. Nuestro objetivo es evaluar el valor predictivo de los valores plasmáticos de PGC-1a en la extensión del área necrótica y el remodelado ventricular tras infarto. [Métodos]: Estudio prospectivo de 31 pacientes con primer infarto de miocardio de localización anterior y reperfusión exitosa. Se determinó la expresión de PGC-1a en sangre periférica al ingreso y a las 72 h, evaluando su correlación con el daño miocárdico y el volumen ventricular y la función sistólica a los 6 meses. El edema y la necrosis miocárdica se estimaron mediante resonancia magnética cardiaca durante la primera semana. A los 6 meses, una resonancia de control evaluó tamaño del infarto y remodelado ventricular, definido como el incremento > 10% del volumen telediastólico del ventrículo izquierdo. Se definió miocardio salvado como la diferencia entre las áreas de edema y de necrosis. [Resultados]: Se observó más miocardio salvado en los pacientes con expresión de PGC-1a detectable al ingreso (el 18.3% [5.3%] vs 4.5% [3.9%]; P = .04). La inducción de PGC-1a a las 72 h se correlacionó con mayor remodelado ventricular (variación del volumen telediastólico del ventrículo izquierdo a los 6 meses, 29.7% [11.2%] vs 1.2% [5.8%]; P = .04). [Conclusiones]: El grado de expresión basal de PGC–1a y una respuesta atenuada del sistema tras infarto agudo de miocardio se asocian con más miocardio salvado y predicen menos remodelado ventricular., This work was financed by the Spanish Society of Cardiology through a grant for Proyectos de Investigación Básica en Cardiología, 2010; the Programa I3 de Intensificación Investigadora 2010 and 2012 from the Instituto de Salud Carlos III and the Generalitat Valenciana; the Fundación para la Investigación del Hospital General Universitario de Valencia through the Becas de Investigación Intramural, 2008 and 2010; the Spanish Ministry of Science and Innovation through projects SAF 2009-07599 and CSD 2007-00020; SAF2012-37693 from MINECO (Ministerio de Economía y Competitividad); and S2010/BMD-2361 from the Community of Madrid.

ARS Open., [Aims]: Sirtuin 1 (SIRT1) is a key player in liver physiology and a therapeutic target against hepatic inflammation. We evaluated the role of SIRT1 in the proinflammatory context and oxidative stress during acetaminophen (APAP)-mediated hepatotoxicity., [Results]: SIRT1 protein levels decreased in human and mouse livers following APAP overdose. SIRT1-Tg mice maintained higher levels of SIRT1 on APAP injection than wild-type mice and were protected against hepatotoxicity by modulation of antioxidant systems and restrained inflammatory responses, with decreased oxidative stress, proinflammatory cytokine messenger RNA levels, nuclear factor kappa B (NFκB) signaling, and cell death. Mouse hepatocytes stimulated with conditioned medium of APAP-treated macrophages (APAP-CM) showed decreased SIRT1 levels; an effect mimicked by interleukin (IL)1β, an activator of NFκB. This negative modulation was abolished by neutralizing IL1β in APAP-CM or silencing p65-NFκB in hepatocytes. APAP-CM of macrophages from SIRT1-Tg mice failed to downregulate SIRT1 protein levels in hepatocytes. In vivo administration of the NFκB inhibitor BAY 11-7082 preserved SIRT1 levels and protected from APAP-mediated hepatotoxicity., [Inovation]: Our work evidenced the unique role of SIRT1 in APAP hepatoprotection by targeting oxidative stress and inflammation., [Conclusion]: SIRT1 protein levels are downregulated by IL1β/NFκB signaling in APAP hepatotoxicity, resulting in inflammation and oxidative stress. Thus, maintenance of SIRT1 during APAP overdose by inhibiting NFκB might be clinically relevant., [Rebound Track]: This work was rejected during standard peer review and rescued by Rebound Peer Review (Antioxid Redox Signal 16:293-296, 2012) with the following serving as open reviewers: Rafael de Cabo, Joaquim Ros, Kalervo Hiltunen, and Neil Kaplowitz. Antioxid. Redox Signal. 28, 1187-1208., This work was funded by SAF2015-65267-R (MINECO/FEDER), CIBERdem (ISCIII, Spain), and INFLAMES (ISCIII PIE14/00045, cofunded by ERDF, ‘‘Investing in your future’’) to A.M.V.; IJCI-2014-19381 (MINECO/FEDER) to P.R. and A.M.V.; SAF2014-52009-R (MINECO/FEDER) to S.A.; SAF2015-63904-R (MINECO/FEDER) to M.M.; CP14/00181 (ISCIII/FEDER) to A.G.-R.; and PI13/00021 (ISCIII/FEDER) to J.M. CIBERehd (ISCIII) to A.G.-R. and J.M.; Grant 37/371 from Al Jouf University to M.A.M. We also acknowledge H2020 Marie Sklodowska-Curie ITNTREATMENT (Grant Agreement No. 721236) (European Commission).

El virus de inmunodeficiencia humana marca la vida de las personas, principalmente en el autocuidado, el trabajo y el tiempo libre, lo cual influye en el ejercicio de la participación social. Objetivo: describir el desempeño ocupacional de 29 pacientes que viven con VIH SIDA y son atendidos por el programa B24 en un Hospital de Bogotá-Colombia. Metodo: estudio descriptivo-exploratorio, recaba información sobre patrones del desempeño, roles ocupacionales e independencia en actividades instrumentales de la vida diaria (AIVD). Se realiza una entrevista y se utiliza el cuestionario ocupacional, el listado de roles y el índice de Lawton y Brody; se procesan los datos en el programa SPSS y se realiza un análisis de frecuencias. Resultados: los participantes tienen en promedio 53 años, el 82.8% son hombres y el 48.3% un nivel de formación superior. Trabajan en promedio 2 horas diarias, invierten en actividades cotidianas alrededor de 11 horas diarias, casi 5 horas a la recreación y 6 horas al descanso. Los roles más significativos son amigo y miembro de familia y el menos significativo miembro de un grupo religioso. El 65.5% es independiente en AIVD, el 31% precisa ayuda para algunas actividades y el 3.4% es dependiente. Los signos y síntomas del VIH y las infecciones oportunistas, dificultan la asunción de roles, incluyendo las actividades socio-laborales. Conclusión: Cobra valor el significado de la transición ocupacional que vive este colectivo y su perspectiva de futuro para implementar programas que propendan por la re-significación de su participación socio-familiar. O vírus da imunodeficiência adquirida afeta a vida das pessoas, principalmente no autocuidado, trabalho e lazer, assim como o exercício da participação social. Objetivo: Descrever o desempenho ocupacional de 29 pessoas que vivem com HIV e AIDS e recebem atenção do programa B24 em um hospital em Bogotá-Colômbia. Método: Estudo descritivo e exploratório sobre os padrões de atuação, papéis ocupacionais e independência nas atividades instrumentais da vida diária (AIVD). Foram usados uma entrevista e um questionário ocupacional, o índice de Lawton e Brody. Os dados foram processados no SPSS para a análise de frequência das variáveis. Resultados: Os participantes têm em média 53 anos, 82,8% homens e 48,3% com formação em educação superior. Eles trabalham uma média de 2 horas por dia e dispendem 11 horas por dia para as atividades diárias, quase 5 ou 6 horas de lazer e descanso. Os papéis mais significativos são de amigo e membro da família, o menos significativo é ser membro de um grupo religioso. 65,5% das pessoas são independentes em AIVD, 31% precisam de ajuda para algumas atividades, só 3,4% são dependentes. Sinais e sintomas de HIV e infecções oportunistas dificultam que se assumam Características del desempeño ocupacional de un grupo de adultos que viven con VIH-SIDA Angélica María Monsalve Robayoa , Martha Rocio Torres Narváeza , Edgar Debray Hernandez Alvareza , Angela González Pucheb , Maira Lizeth Peña Duartea , María Angélica Zúñiga Peñaa a Universidad del Rosario, Bogotá, Colombia. b Hospital Universitario Mayor, Bogotá, Colombia. Cad. Ter. Ocup. UFSCar, São Carlos, v. 25, n. 1, p. 85-93, 2017 86 Características del desempeño ocupacional de un grupo de adultos que viven con VIH-SIDA 1 Introduccion El VIH-SIDA se ha tornado en un tema central de salud pública a nivel mundial; ello a causa de las alarmantes cifras de contagio y mortalidad, en parte debido al bajo acceso a un tratamiento oportuno. Según las últimas estimaciones realizadas, en el mundo hay 33.3 millones de personas que padecen el VIH/SIDA y en el 2009 se produjeron 2.6 millones de nuevas infecciones. En la situación epidemiológica actual del VIH/SIDA en el mundo, Latinoamérica ocupa el cuarto lugar en incidencia y prevalencia, seguido de África, Europa y Asia (TEVA et al., 2012). Colombia ha sido clasificada como un país donde el VIH/SIDA es una epidemia muy concentrada, debido a su rápida propagación por una o más poblaciones aunque no se haya extendido entre la población en general (COLOMBIA…, 2014), se encuentra en la primera posición en porcentaje de hombres jóvenes con VIH/SIDA y en segunda posición en porcentaje de niños (TEVA et al., 2012). Colombia se encuentra en el puesto 34 dentro de la comparación realizada entre 122 países, con una cifra de 136.500 personas infectadas con VIH y con vida al final del año (CENTRAL…, 2014) El Ministerio de Salud y Protección Social de la República de Colombia (2014), afirma que desde 1985 al 31 de diciembre de 2012 se ha reportado un total de 95.187 casos nuevos de infección por VIH Sida lo que evidencia el incremento anual de casos a nivel nacional. Lo anterior refleja una situación inquietante en el país y la necesidad de implementar proyectos para su prevención y acceso al tratamiento. En Colombia la ley 972 de 2005, establece los lineamientos para mejorar la atención a personas con enfermedades catastróficas, específicamente el VIH SIDA y ratifica la importancia de considerar el manejo del estigma como un elemento principal (COLOMBIA, 2005). Por otro lado, se ha evidenciado el progreso en cuanto a programas preventivos y acceso al tratamiento, lo cual ha reducido la cantidad de muertes y contagios. El informe del día mundial del SIDA reporta una reducción en un 50% de la infección por VIH en 25 países de ingresos bajos y medios; cabe anotar que la calidad de vida de las personas está directamente asociada al sentido que tiene ésta y cómo se reconoce la posibilidad de involucrarse con el tratamiento médico y los cambios generados a nivel social. A pesar del progreso en cuanto a la reducción de la infección y la implementación de proyectos de salud pública, se ha desarrollado y mantenido un estigma que afecta directamente el desempeño ocupacional de la persona portadora de VIH, entendiendo desempeño ocupacional como el producto de la interacción papéis, incluindo atividades de trabalho. Conclusão: o valor Cobra demonstra o significado de transição profissional para este grupo e suas perspectivas futuras para implementar programas que promovam a importância da sua participação social e familiar.

SirT1 is a class III histone deacetylase that has been implicated in metabolic and reactive oxygen species control. In the vasculature it has been shown to decrease endothelial superoxide production, prevent endothelial dysfunction and atherosclerosis. However, the mechanisms that mediate SirT1 antioxidant functions remain to be characterized. The transcription factor FoxO3a and the transcriptional coactivator peroxisome proliferator activated receptor γ-coactivator 1α (PGC-1α) have been shown to induce the expression of antioxidant genes and to be deacetylated by SirT1. [Aims]: Here we investigated SirT1 regulation of antioxidant genes and the roles played by FoxO3a and PGC-1α in this regulation. [Results]: We found that SirT1 regulates the expression of several antioxidant genes in bovine aortic endothelial cells, including Mn superoxide dismutase (MnSOD), catalase, peroxiredoxins 3 and 5 (Prx3, Prx5), thioredoxin 2 (Trx2), thioredoxin reductase 2 (TR2), and uncoupling protein 2 (UCP-2) and can be localized in the regulatory regions of these genes. We also found that knockdown of either FoxO3a or PGC-1α prevented the induction of antioxidant genes by SirT1 over-expression. Furthermore, SirT1 increased the formation of a FoxO3a/PGC-1α complex as determined by co-immunoprecipitation (IP) assays, concomitantly reducing H2O2-dependent FoxO3a and PGC-1α acetylation. Data showing that FoxO3a knockdown increases PGC-1α acetylation levels and vice versa, suggest that SirT1 activity on FoxO3a and PGC-1α may be dependent of the formation of a FoxO3a/PGC-1α complex. [Innovation]: A unifying mechanism for SirT1 activities is suggested. [Conclusion]: We show that SirT1 regulation of antioxidant genes in vascular endothelial cells depends on the formation of a FoxO3a/PGC-1α complex., This work was supported by the Spanish ‘‘Ministerio de Economía y Competitividad’’ (grants SAF2009-07599 to M.M, SAF 2009-07520 to S.L. and CSD 2007-00020 to M.M. and S.L.) and the ‘‘Comunidad Autónoma de Madrid’’ (grant S2010/BMD-2361 to M.M.).

Resumen del póster presentado al OCC World Congress and Annual SFRR-E Conference: "Metabolic Stress and Redox Regulation", celebrados en Berlin (Alemania) del 21 la 23 de junio de 2017., Liver steatosis is associated with mitochondrial dysfunction and elevated Reactive Oxygen Species (ROS) levels together with enhanced sensitivity to IR injury and limited response to preconditioning protocols. Here, we sought to determine whether the downregulation in the steatotic liver of PGC-1a, a master regulator of mitochondrial metabolism and ROSl, could be responsible for the sensitivity of steatotic liver to ischemic damage. PGC-1a was induced in normal liver following exposure to an IR protocol concomitant with an increase in the levels of antioxidant proteins. By contrast, its induction was severely blunted in steatotic liver, resulting in a modest induction of antioxidant proteins. Livers of PGC-1a-/- mice on chow diet were normal, but they exhibited an enhanced sensitivity to IR injury and also a lack of response to ischemic preconditioning, a phenotype that recapitulated the features of steatotic liver in terms of liver damage. Utilizing an in vitro model of IPC, we found that PGC-1a expression was downregulated in hepatic cells cultured at 1% O2 whereas it was induced following reoxygenation (3% O2), and was responsible for the recovery of antioxidant gene expression following the ischemic period. We concluded that PGC-1a plays an important role in the protection against IR injury in the liver, which is likely associated with its capacity to induce antioxidant gene expression., Funding was provided by MINEICO, FEDER Funds, Comunidad Autónoma de Madrid, ISCIII.

[Aims]: A loss in brain acetylcholine and cholinergic markers, subchronic inflammation, and impaired mitochondrial function, which lead to low-energy production and high oxidative stress, are common pathological factors in several neurodegenerative diseases (NDDs). Glial cells are important for brain homeostasis, and microglia controls the central immune response, where α7 acetylcholine nicotinic receptors (nAChR) seem to play a pivotal role; however, little is known about the effects of this receptor in metabolism. Therefore, the aim of this study was to evaluate if glial mitochondrial energetics could be regulated through α7 nAChR. [Results]: Primary glial cultures treated with the α7 nicotinic agonist PNU282987 increased their mitochondrial mass and their mitochondrial oxygen consumption without increasing oxidative stress; these changes were abolished when nuclear erythroid 2-related factor 2 (Nrf2) was absent, heme oxygenase-1 (HO-1) was inhibited, or peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) was silenced. More specifically, microglia of animals treated intraperitoneally with the α7 nAChR agonist PNU282987 (10 mg/kg) showed a significant increase in mitochondrial mass. Interestingly, LysMcre-Hmox1Δ/Δ and PGC-1α−/− animals showed lower microglial mitochondrial levels and treatment with PNU282987 did not produce effects on mitochondrial levels., [Innovation]: Increases in microglial mitochondrial mass and metabolism can be achieved via α7 nAChR by a mechanism that implicates Nrf2, HO-1, and PGC-1α. This signaling pathway could open a new strategy for the treatment of NDDs, such as Alzheimer's, characterized by a reduction of cholinergic markers. [Conclusion]: α7 nAChR signaling increases glial mitochondrial mass, both in vitro and in vivo, via HO-1 and PCG-1α. These effects could be of potential benefit in the context of NDDs., This work was supported by the Spanish Ministry of Economy and Competence Ref. SAF2012-23332 and SAF2015-63935-R to M.G.L.; Ref. SAF2012-37693 to M.M. Comunidad Autónoma de Madrid grant number S2010/BMD-2361 to M.M. E.N. a predoctoral fellowship from Universidad Autónoma de Madrid. The work in SC laboratory is supported by grants from the Instituto de Salud Carlos III FIS (PI12/00933 and PI15/00448) and by Comunidad de Madrid (S2011/BMD-2402). We also thank the Fundación Teófilo Hernando, the Network of Excellence Nrf2-net of MINECO, and the European Cooperation and Technology (COST Action BM1203/EU-ROS).

Peroxisome proliferator activated receptor α (PPARα) is a distinctive marker of the brown fat phenotype that has been proposed to coordinate the transcriptional activation of genes for lipid oxidation and for thermogenic uncoupling protein 1 in brown adipose tissue. Here, we investigated the involvement of PPARα in the transcriptional control of the PPARγ coactivator (PGC)-1α gene. Treatment with PPARα agonists induced PGC-1α mRNA expression in brown fat in vivo and in primary brown adipocytes. This enhancement of PGC-1α transcription was mediated by PPARα binding to a PPAR-responsive element in the distal PGC-1α gene promoter. PGC-1α gene expression was decreased in PPARα-null brown fat, both under basal conditions and in response to thermogenic activation. Moreover, PPARα- and cAMP-mediated pathways interacted to control PGC-1α transcription. PRDM16 (PRD1-BF1-RIZ1 homologous domain-containing 16) promoted PPARα induction of PGC-1α gene transcription, especially under conditions in which protein kinase A pathways were activated. This enhancement was associated with the interaction of PRDM16 with the PGC-1α promoter at the PPARα-binding site. In addition, PPARα promoted the expression of the PRDM16 gene in brown adipocytes, and activation of PPARα in human white adipocytes led to the appearance of a brown adipocyte pattern of gene expression, including induction of PGC-1α and PRDM16. Collectively, these results suggest that PPARα acts as a key component of brown fat thermogenesis by coordinately regulating lipid catabolism and thermogenic gene expression via induction of PGC-1α and PRDM16.

El pdf es el manuscrito de autor.-- et al., [Aims]: The epidermal growth factor-like protein Delta-like 1 (DLK1) regulates multiple differentiation processes. It resembles NOTCH ligands structurally and is considered a non-canonical ligand. Given the crucial role of the NOTCH pathway in angiogenesis, we hypothesized that DLK1 could regulate angiogenesis by interfering with NOTCH. We therefore investigated the expression and function of DLK1 in the vascular endothelium and its role in the regulation of angiogenesis., [Methods and Results]: We report DLK1 expression in the endothelium of different species, including human, cow, pig, and mouse. Angiogenesis was studied by using in vitro and in vivo models of angiotube formation in endothelial cells, retinal phenotypes in Dlk1-null mice, and vessel development in zebrafish. DLK1 overexpression strongly inhibited angiotube formation, whereas lung endothelial cells from Dlk1-null mice were highly angiogenic. In vivo studies demonstrated DLK1-mediated inhibition of neovessel formation and revealed an altered pattern of angiogenesis in the retinas of Dlk1-null mice. The expression of human DLK1 in zebrafish embryos severely altered the formation of intersegmental vessels, while knockdown of the orthologous gene was associated with ectopic and increased tumour-induced angiogenesis. NOTCH-dependent signalling as determined by gene expression reporters was inhibited by the presence of DLK1 in vascular endothelial cells. In contrast, Dlk1-null mice showed increased levels of NOTCH downstream targets, such as Snail and Slug., [Conclusion]: Our results unveil a novel inhibitory role for DLK1 in the regulation of angiogenesis, mediated by antagonism of the NOTCH pathway, and establish the basis for investigating its action in pathological settings., This work was supported by the conjoint grant Cardiovrep S2006/BIO-0194 from the Comunidad Autónoma de Madrid (to S.L., J.L.P., and J.M.R.), CSD 2007-00020 (to S.L. and M.M.), SAF2009-07520 (to S.L.), and BFU2007-61094 (to J.L.) all from the Spanish Ministerio de Ciencia e Innovación (MICINN).

Chronic cholestasis is characterizedby mitochondrial dysfunction, associated with loss of mitochondrialmembrane potential, decreased activities of respiratory chaincomplexes, and ATP production. Our aim was to determine themolecular mechanisms that link long-term cholestasis to mitochondrialdysfunction. We studied a model of chronic cholestasis inducedby bile duct ligation in rats. Key sensors and regulators of theenergetic state and mitochondrial biogenesis, mitochondrial DNA(mtDNA)-to-nuclear DNA (nDNA) ratio (mtDNA/nDNA) relativecopy number, mtDNA deletions, and indexes of apoptosis (BAX,BCL-2, and cleaved caspase 3) and cell proliferation (PCNA) wereevaluated. Our results show that long-term cholestasis is associatedwith absence of activation of key sensors of the energetic state,evidenced by decreased SIRT1 and pyruvate dehydrogenase kinaselevels and lack of AMPK activation. Key mitochondrial biogenesisregulators (PGC-1α and GABP-α) decreased and NRF-1 was nottranscriptionally active. Mitochondrial transcription factor A (TFAM)protein levels increased transiently in liver mitochondria at 2 wk afterbile duct ligation, but they dramatically decreased at 4 wk. ReducedTFAM levels at this stage were mirrored by a marked decrease (65%)in mtDNA/nDNA relative copy number. The blockade of mitochondrialbiogenesis should not be ascribed to activation of apoptosis orinhibition of cell proliferation. Impaired mitochondrial turnover andloss of the DNA stabilizing effect of TFAM are likely the causativeevent involved in the genetic instability evidenced by accumulation ofmtDNA deletions. In conclusion, the lack of stimulation of mitochondrialbiogenesis leads to mtDNA severe depletion and deletions inlong-term cholestasis. Hence, long-term cholestasis should be considereda secondary mitochondrial hepatopathy., This work was supported by Grants CSD-2007-00020, SAF2006-06963, and SAF2009-09500 from Ministerio de Ciencia e Innovación together with FEDER funds to J. Sastre and Grant Prometeo/2010/074 to J. Viña.

Nitric oxide (NO•) is a vasodilator compound responsible for different physiological processes and its decrease in vasculature may lead to endothelial dysfunction. The main pathway related to the decrease in NO• bioavailability is its reaction with the superoxide radical (O2•-) with consequent production of peroxynitrite (ONOO-). Thus, we aim to evaluate the protective effect of diphenyl diselenide (PhSe)2 on bovine aortic endothelial cells culture (BAEC), clarifying the participation of this compound during nitroxidative stress and mitochondrial modulation. Thus, BAEC were treated at different times and concentrations (1–1000 nM) of (PhSe)2 and exposed to SIN-1 (ONOO- donor). The treatment with (PhSe)2 was able to prevent the formation of ONOO- in time and concentration-dependent manner analyzed by the DHR probe test. By high resolution respirometry (Oroboros), the treatment with (PhSe)2 (1 µM) was able to modulate different respiratory states, such as the increase of the maximum respiratory capacity and the consumption of oxygen coupled to ATP synthesis. Thus, we hypothesized that the activation of transcription factors such as Nrf-2 and FOXO3a by (PhSe)2 render cells more resistance to oxidative damage and consequent mitochondrial dysfunction.

Peroxisome proliferator activated receptor g co-activator 1alpha (PGC-1α) is a regulator of oxidative metabolism and reactive oxygen species (ROS) homeostasis that has been show to play a relevant role in angiogenesis. PGC-1α KO mice show reduced vascular density in the retinas and KO primary vascular endothelial cells (ECs) migrate faster than the wild type, an effect that can be rescued by antioxidants, suggesting that excessive ROS levels might be relevant in PGC-1 α role in angiogenesis. This study aims to investigate the role of ROS homeostasis on the regulation by PGC-1 α of angiogenesis. We found that endothelial cells (ECs) from mice deleted for PGC-1 α display attenuated adhesion to the extracellular matrix, together with slower spreading, reduced formation of cellular junctions, a disorganized cytoskeleton and random motility, and a enhanced tip phenotype. Aditionally, PGC-1 α -deleted ECs exhibit an altered response to vascular endothelial growth factor-A (VEGF-A). In vivo, deletion of PGC-1 α results in addition to reduced retinal vascular density, sparse pericyte coverage. Exposure of PGC-1 α deleted mice to hyperoxia during retinal vascular development exacerbates these vascular abnormalities and mice show extensive retinal hemorrhaging, with highly unstructured areas and very poor perfusion, compared with wild-type mice. Structural analysis demonstrates a reduction of endothelial VE-cadherin, suggesting defective inter-cellular junctions. Interestingly, this hyperoxia-induced phenotype is partially reversed by antioxidant administration, indicating that elevated production of mitochondrial reactive oxygen species (ROS) in the absence of PGC-1 α is functionally important. Finally, in vitro studies show that antioxidant treatment improves VEGF-A signaling, suggesting that toxic effect of ROS may be caused by the alteration of the VEGF-A signaling pathway. In summary, our findings indicate that PGC-1 α control of ROS homeostasis plays an important role in the control of de novo angiogenesis, and is required for vascular stability.

12 páginas, 7 figuras, 1 tabla.-- et al., Retinol binding protein-4 (RBP4) is a serum protein involved in the transport of vitamin A. It is known to be produced by the liver and white adipose tissue. RBP4 release by white fat has been proposed to induce insulin resistance. We analyzed the regulation and production of RBP4 in brown adipose tissue. RBP4 gene expression is induced in brown fat from mice exposed to cold or treated with peroxisome proliferator-activated receptor (PPAR) agonists. In brown adipocytes in culture, norepinephrine, cAMP, and activators of PPARγ and PPARα induced RBP4 gene expression and RBP4 protein release. The induction of RBP4 gene expression by norepinephrine required intact PPAR-dependent pathways, as evidenced by impaired response of the RBP4 gene expression to norepinephrine in PPARα-null brown adipocytes or in the presence of inhibitors of PPARγ and PPARα. PPARγ and norepinephrine can also induce the RBP4 gene in white adipocytes, and over expression of PPARα confers regulation by this PPAR subtype to white adipocytes. The RBP4 gene promoter transcription is activated by cAMP, PPARα, and PPARγ. This is mediated by a PPAR-responsive element capable of binding PPARα and PPARγ and required also for activation by cAMP. The induction of the RBP4 gene expression by norepinephrine in brown adipocytes is protein synthesis dependent and requires PPARα-coactivator- 1-α, which acts as a norepinephine-induced coactivator of PPAR on the RBP4 gene. We conclude that PPARγ- and PPARγ-mediated signaling controls RBP4 gene expression and releases in brown adipose tissue, and thermogenic activation induces RBP4 gene expression in brown fat through mechanisms involving PPARγ-coactivator-1-α coactivation of PPAR signaling. Copyright © 2012 by The Endocrine Society., This work was supported by the Ministerio de Ciencia e Innovación Grant SAF2008-01896, SAF2011-23636 and Fondo de Investigaciones Sanitarias Grant PI081715, Spain. Centro de Investigación Biomédica en Red Fisiopatologia de la Obesidad y Nutrición is an initiative of Instituto de Salud Carlos III Spain, and Grant HEALTH-F2-2011-277713 by the European Union.

Low mitochondriogenesis is critical to explain loss of muscle function in aging and in the development of frailty. The aim of this work was to explain the mechanism by which mitochondriogenesis is decreased in aging and to determine to which extent it may be prevented by exercise training. We used aged rats and compared them with peroxisome proliferator-activated receptor-γ coactivator-1α deleted mice (PGC-1α KO). PGC-1α KO mice showed a significant decrease in the mitochondriogenic pathway in muscle. In aged rats, we found a loss of exercise-induced expression of PGC-1α, nuclear respiratory factor-1 (NRF-1), and of cytochrome C. Thus muscle mitochondriogenesis, which is activated by exercise training in young animals, is not in aged or PGC-1α KO ones. Other stimuli to increase PGC-1α synthesis apart from exercise training, namely cold induction or thyroid hormone treatment, were effective in young rats but not in aged ones. To sum up, the low mitochondrial biogenesis associated with aging may be due to the lack of response of PGC-1α to different stimuli. Aged rats behave as PGC-1α KO mice. Results reported here highlight the role of PGC-1α in the loss of mitochondriogenesis associated with aging and point to this important transcriptional coactivator as a target for pharmacological interventions to prevent age-associated sarcopenia., This work was supported by grants SAF2008-00270, SAF2009-08334, and BFU2007-65803/BFI from the Spanish Ministry of Education and Science; PROMETEO/2010/074 from the Consellería de Educación de la Generalitat Valenciana. ISCIII2006-RED13-027 from the “Red Temática de Investigación Cooperativa en Envejecimiento y Fragilidad (RETICEF)”, EU Funded COSTB35 and DPS2008-06968 from Spanish Ministry of Innovation and Science. This study has been cofinanced by FEDER funds from the European Union.

et al., Cholestatic liver diseases are characterized by blockade of bile flow from the liver to the intestine, and accumulation of hydrophobic bile acids in the liver and plasma. As a consequence an inflammatory response evolves associated with increased apoptosis, oxidative stress, and eventually fibrosis. Cholestasis is associated with profound metabolic changes, alterations in the mitochondrial function, decreased fatty acid oxidation, and increased glycolisis. Mitochondria play a central role in the development of this liver disease because they mediate death receptor signaling - triggered by inflammatory cytokines or bile acids - and contribute to oxidative damage, metabolic disorder, and onset of fibrosis. During the pathogenesis of biliary cirrhosis mitochondria's need for renewal is hampered by a blunted mitochondrial biogenesis. Lack of stimulation of mitochondrial renewal helps to explain mitochondrial impairment in long-term cholestasis. The marked depletion of mitochondrial DNA and occurrence of mitochondrial DNA deletions are probably relevant contributors to the progression of this severe disease. All these findings certainly support the consideration of long-term cholestasis as a secondary mitochondrial hepatopathy.

FOXO transcription factors control proliferation, apoptosis, differentiation and metabolic processes. Loss of FOXO function has been identified in several human cancers, and results in increased cellular survival and a predisposition to neoplasia, especially in epithelial cancer. FOXO factors are therefore bona fide tumor suppressors, and their potential use as therapeutic targets in cancer has been a matter of debate. Importantly, FOXO factors can also positively regulate cell survival through the activation of several detoxification genes, complicating its putative therapeutic potential. Targeting of FOXO factors has also been proposed for the treatment of metabolic dysfunctions such as diabetes mellitus, immunological disorders and neurodegeneration, as well as for the prevention of aging by maintaining the hematopoyetic stem cells niche. But again, data has accumulated that cautions against the potential use of the FOXO activators in these settings. Therefore, greater understanding of the regulation of FOXO target specificity is still needed to boost its use as a therapeutic target. The four members of the FOXO family (FOXO1, FOXO3A, FOXO4 and FOXO6) have distinct but overlapping cellular functions, although they seem to bind a common set of DNA sites. This fact together with the observation that FOXOs are only partially dependent on their DNA binding activity to regulate their target genes highlights the fact that the interaction of the FOXOs with other transcription factors is crucial for the FOXO-mediated transcriptional programs. In this review, we provide an overview of recent progress in the understanding of the modulation of FOXO activity and target specificity by transcription factors and coactivators. © 2011 Bentham Science Publishers Ltd., This work was supported Ministry of Science and Innovation (grants SAF2006-01619, SAF2009-07599 and CSD 2007-00020 to M.M.). CNIC is supported by the Spanish Ministry of Health and Consumer Affairs and the Pro-CNIC Foundation.

In damaged or proliferating endothelium, production of nitric oxide (NO) from endothelial nitric oxide synthase (eNOS) is associated with elevated levels of reactive oxygen species (ROS), which are necessary for endothelial migration. We aimed to elucidate the mechanism that mediates NO induction of endothelial migration. NO downregulates expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), which positively modulates several genes involved in ROS detoxification. We tested whether NO-induced cell migration requires PGC-1α downregulation and investigated the regulatory pathway involved. PGC-1α negatively regulated NO-dependent endothelial cell migration in vitro, and inactivation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway, which is activated by NO, reduced NO-mediated downregulation of PGC-1α. Expression of constitutively active Foxo3a, a target for Akt-mediated inactivation, reduced NO-dependent PGC-1α downregulation. Foxo3a is also a direct transcriptional regulator of PGC-1α, and we found that a functional FoxO binding site in the PGC-1α promoter is also a NO response element. These results show that NO-mediated downregulation of PGC-1α is necessary for NO-induced endothelial migration and that NO/protein kinase G (PKG)-dependent downregulation of PGC-1α and the ROS detoxification system in endothelial cells are mediated by the PI3K/Akt signaling pathway and subsequent inactivation of the FoxO transcription factor Foxo3a., This work was supported by the Spanish Ministry of Science and Innovation (grants SAF2006-01619 and SAF2009-07599 to M.M., grant CSD 2007-00020 to M.M. and S.L., and grants SAF2006-02410 and SAF2009-07520 to S.L.), the Spanish Society of Nephrology (grant-in-aid to S.L.), a CNIC-Bancaja predoctoral fellowship to I.V., and an Instituto de Salud Carlos III (ISCIII) contrato de apoyo a la investigación to F.M.-G. The CNIC is supported by the Spanish Ministry of Science and Innovation and the Pro-CNIC Foundation.

Oxidative stress is a hallmark of metabolism-related diseases and a risk factor for atherosclerosis. FoxO factors have been shown to play a key role in vascular endothelial development and homeostasis. Foxo3a can protect quiescent cells from oxidative stress through the regulation of detoxification genes such as sod2 and catalase. Here we show that Foxo3a is a direct transcriptional regulator of a group of oxidative stress protection genes in vascular endothelial cells. Importantly, Foxo3a activity requires the transcriptional co-activator PGC-1α, because it is severely curtailed in PGC-1α-deficient endothelial cells. Foxo3a and PGC-1α appear to interact directly, as shown by co-immunoprecipitation and in vitro interaction assays, and are recruited to the same promoter regions. The notion that Foxo3a and PGC-1α interact directly to regulate oxidative stress protection genes in the vascular endothelium is supported by the observation that PGC-1α transcriptional activity at the sod2 (manganese superoxide dismutase) promoter requires a functional FoxO site. We also demonstrate that Foxo3a is a direct transcriptional regulator of PGC-1α, suggesting that an auto-regulatory cycle regulates Foxo3a/PGC-1α control of the oxidative stress response., This work was supported in part by Grant SAF2006-01619 from the Plan Nacional de I+D+I of the Ministerio de Educación y Ciencia (to M. M.), Grant CSD 2007-00020 from the Ministerio de Educación y Ciencia (to M. M. and S. L.), and Grant SAF2006-02410 from the Ministerio de Educación y Ciencia and a grant-in-aid from the Spanish Society of Nephrology (to S. L.). The Centro Nacional de Investigaciones Cardiovasculares is supported by the Spanish Ministry of Health and Consumer Affairs and the Pro-Centro Nacional de Investigaciones Cardiovasculares Foundation.

The integrity of mitochondrial function is fundamental to cell life. The cell demands for mitochondria and their complex integration into cell biology, extends far beyond the provision of ATP. It follows that disturbances of mitochondrial function lead to disruption of cell function, expressed as disease or even death. Mitochondria are major producers of free radical species and also possibly of nitric oxide, and are, at the same time, major targets for oxidative damage. In this review we consider recent developments in our knowledge of how the mitochondrial production of reactive oxygen species (ROS) plays a critical role in several major human pathologies. We will also consider recent advances in our understanding of the molecular mechanisms involved in mitochondrial ROS detoxification., This work was supported by an institutional grant from the CNIC, by Plan Nacional de I+D+I grants SAF2003-01039 and SAF2003-04901 and grant-in-aid from the Spanish Society of Nephrology to Dr. Santiago Lamas. Sara Borniquel is holder of grant SAF2003-04901 predoctoral fellowship. Inmaculada Valle is holder of a CNIC-Bancaja predoctoral fellowship. Maria Monsalve is holder of a Ramon y Cajal contract from the Ministerio de Educación y Ciencia.

Nitric oxide (NO) has both prooxidant and antioxidant activities in the endothelium; however, the molecular mechanisms involved are still a matter of controversy. PGC-1α [peroxisome proliferators-activated receptor (PPAR) γ coactivator 1-α] induces the expression of several members of the mitochondrial reactive oxygen species (ROS) detoxification system. Here, we show that NO regulates this system through the modulation of PGC-1α expression. Short-term (24 h) treatment up-regulates it. Treatment with the NOS inhibitor L-NAME has the opposite effect. Downregulation of PGC-1α by NO is mediated by protein kinase G (PKG). It is blocked by the soluble guanylate cyclase (sGC) inhibitor ODQ and the PKG inhibitor KT5823, and mimicked by the cGMP analog 8-Br-cGMP. Changes in PGC-1α expression are in all cases paralleled by corresponding variations in the mitochondrial ROS detoxification system. Cells that transiently overexpress PGC-1α from the cytomeglovirus (CMV) promoter respond poorly to NO donors. Analysis of tissues from eNOS-/- mice showed reduced levels of PGC-1α and the mitochondrial ROS detoxification system. These data suggest that NO can regulate the mitochondrial ROS detoxification system both positively and negatively through PGC-1α., This work was supported by an institutional grant from the CNIC, Plan Nacional de I+D+I grants SAF2003–01039, SAF2003–04901, BFI2003–03493, and grant-in-aid from the Spanish Society of Nephrology to S.L. S.B. is a holder of a predoctoral fellowship under grant SAF2003–04901. Inmaculada Valle is a holder of a CNIC-Bancaja predoctoral fellowship. M.M. and S.C. are holders of a Ramon&Cajal contract from the Ministerio de Educación y Ciencia.

Transcription of the genome of Bacillus subtilis phage Φ29 is tightly controlled, taking place in two stages, early and late. We have analyzed the abundance of the transcripts produced from each viral promoter throughout the infection cycle. We compare the relative strength of each promoter, as well as get a better understanding of the regulatory events, finding a new promoter regulated by the viral protein p4. The two strong early promoters, A2b and A2c, responsible for the expression of genes 6 to 1, are coordinately repressed by the viral protein p4, although repression is not complete; both promoters are still active at late times of infection. Since repression by protein p4 was very efficient in vitro, and affects its own synthesis, it is likely that this protein is produced in limiting amounts, not being bound to all viral DNA molecules present in the cell at a given time. Protein p4, also known to activate the late promoter responsible for the expression of all the structural end morphogenetic genes, is the key regulator of phage Φ29 development.

PGC‐1α (peroxisome proliferator‐activated receptor gamma coactivator‐1α, PPARGC1A) regulates the expression of genes involved in energy homeostasis and mitochondrial biogenesis. Here we identify inactivation of the transcriptional regulator PGC‐1α as a landmark for experimental nephrotoxic acute kidney injury (AKI) and describe the in vivo consequences of PGC‐1α deficiency over inflammation and cell death in kidney injury. Kidney transcriptomic analyses of WT mice with folic acid‐induced AKI revealed 1398 up‐ and 1627 downregulated genes. Upstream transcriptional regulator analyses pointed to PGC‐1α as the transcription factor potentially driving the observed expression changes with the highest reduction in activity. Reduced PGC‐1α expression was shared by human kidney injury. Ppargc1a−/− mice had spontaneous subclinical kidney injury characterized by tubulointerstitial inflammation and increased Ngal expression. Upon AKI, Ppargc1a−/− mice had lower survival and more severe loss of renal function, tubular injury, and reduction in expression of mitochondrial PGC‐1α‐dependent genes in the kidney, and an earlier decrease in mitochondrial mass than WT mice. Additionally, surviving Ppargc1a−/− mice showed higher rates of tubular cell death, compensatory proliferation, expression of proinflammatory cytokines, NF‐κB activation, and interstitial inflammatory cell infiltration. Specifically, Ppargc1a−/− mice displayed increased M1 and decreased M2 responses and expression of the anti‐inflammatory cytokine IL‐10. In cultured renal tubular cells, PGC‐1α targeting promoted spontaneous cell death and proinflammatory responses. In conclusion, PGC‐1α inactivation is a key driver of the gene expression response in nephrotoxic AKI and PGC‐1α deficiency promotes a spontaneous inflammatory kidney response that is magnified during AKI., Sandra Zazo and Federico Rojo of the IIS‐FJD Biobank (B.0000647). FIS/Fondos FEDER (PI15/00298, CP14/00133, PI16/02057, PI16/01900, ISCIII‐RETIC REDinREN RD016/0009), Sociedad Española de Nefrología, FRIAT, Comunidad de Madrid en Biomedicina B2017/BMD‐3686 CIFRA2‐CM. Grants from the Spanish ‘Ministerio de Economía Industria y Competitividad’ (MINEICO) and FEDER funds (Grant numbers SAF2015‐63904‐R, SAF2015‐71521‐REDC), and from the EC H2020 framework program Grant MSCA‐ITN‐2016‐721236 to MM. Salary support: ISCIII Miguel Servet and to ABS and MDS‐N. ISCIII Sara Borrell to JM‐MM, and Fundación Conchita Rabago to DMS. Consejería de Educación, Juventud y Deporte (Comunidad de Madrid/FSE) to MF‐B.

Obesity is associated with local and systemic complications in acute pancreatitis. PPARγ coactivator 1α (PGC-1α) is a transcriptional coactivator and master regulator of mitochondrial biogenesis that exhibits dysregulation in obese subjects. Our aims were: (1) to study PGC-1α levels in pancreas from lean or obese rats and mice with acute pancreatitis; and (2) to determine the role of PGC-1α in the inflammatory response during acute pancreatitis elucidating the signaling pathways regulated by PGC-1α. Lean and obese Zucker rats and lean and obese C57BL6 mice were used first; subsequently, wild-type and PGC-1α knockout (KO) mice with cerulein-induced pancreatitis were used to assess the inflammatory response and expression of target genes. Ppargc1a mRNA and protein levels were markedly downregulated in pancreas of obese rats and mice versus lean animals. PGC-1α protein levels increased in pancreas of lean mice with acute pancreatitis, but not in obese mice with pancreatitis. Interleukin-6 (Il6) mRNA levels were dramatically upregulated in pancreas of PGC-1α KO mice after cerulein-induced pancreatitis in comparison with wild-type mice with pancreatitis. Edema and the inflammatory infiltrate were more intense in pancreas from PGC-1α KO mice than in wild-type mice. The lack of PGC-1α markedly enhanced nuclear translocation of phospho-p65 and recruitment of p65 to Il6 promoter. PGC-1α bound phospho-p65 in pancreas during pancreatitis in wild-type mice. Glutathione depletion in cerulein-induced pancreatitis was more severe in KO mice than in wild-type mice. PGC-1α KO mice with pancreatitis, but not wild-type mice, exhibited increased myeloperoxidase activity in the lungs, together with alveolar wall thickening and collapse, which were abrogated by blockade of the IL-6 receptor glycoprotein 130 with LMT-28. In conclusion, obese rodents exhibit PGC-1α deficiency in the pancreas. PGC-1α acts as selective repressor of nuclear factor-κB (NF-κB) towards IL-6 in pancreas. PGC-1α deficiency markedly enhanced NF-κB-mediated upregulation of Il6 in pancreas in pancreatitis, leading to a severe inflammatory response., This work was supported by grants SAF2009‐09500 and SAF2015–71208‐R with FEDER funds from the Spanish Ministry of Economy and Competitiveness to JS and by grants SAF2015‐63904‐R with FEDER funds from the Spanish Ministry of Economy and Competitiveness and EC MSCA‐ITN‐2016‐721236 to MM. IF was recipient of a fellowship from ‘Programa de Pós‐Doutorado no Exterior (PDE)’ that belongs to the ‘Conselho Nacional de Desenvolvimento Científico e Tecnológico’ (CNPq).

Melatonin, an indole produced by pineal and extrapineal tissues, but also taken with a vegetarian diet, has strong anti-oxidant, anti-inflammatory and anti-obesogenic potentials. Non-alcoholic fatty liver disease (NAFLD) is the hepatic side of the metabolic syndrome. NAFLD is a still reversible phase but may evolve into steatohepatitis (NASH), cirrhosis and carcinoma. Currently, an effective therapy for blocking NAFLD staging is lacking. Silent information regulator 1 (SIRT1), a NAD+ dependent histone deacetylase, modulates the energetic metabolism in the liver. Micro-RNA-34a-5p, a direct inhibitor of SIRT1, is an emerging indicator of NAFLD grading. Thus, here we analyzed the effects of oral melatonin against NAFLD and underlying molecular mechanisms, focusing on steatosis, ER stress, mitochondrial shape and autophagy. Male C57BL/6J (WT) and SIRT1 heterozygous (HET) mice were placed either on a high-fat diet (58.4% energy from lard) (HFD) or on a standard maintenance diet (8.4% energy from lipids) for 16 weeks, drinking melatonin (10 mg/kg) or not. Indirect calorimetry, glucose tolerance, steatosis, inflammation, ER stress, mitochondrial changes, autophagy and microRNA-34a-5p expression were estimated. Melatonin improved hepatic metabolism and steatosis, influenced ER stress and mitochondrial shape, and promoted autophagy in WT HFD mice. Conversely, melatonin was ineffective in HET HFD mice, maintaining NASH changes. Indeed, autophagy was inconsistent in HET HFD or starved mice, as indicated by LC3II/LC3I ratio, p62/SQSTM1 and autophagosomes estimation. The beneficial role of melatonin in dietary induced NAFLD/NASH in mice was related to reduced expression of microRNA-34a-5p and sterol regulatory element-binding protein (SREBP1) but only in the presence of full SIRT1 availability., This research was funded by FFABR 2017, 60% from grants of University of Brescia (Italy) and grants by the Spanish “Ministerio de Economía Industria y Competitividad” (MINEICO) including FEDER funds (SAF2015-63904-R) and the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie agreement 721236-TREATMENT to M.M.