Publications by authors named "Maria-Jesus Vazquez"

25 Publications

  • Page 1 of 1

Central Ceramide Signaling Mediates Obesity-Induced Precocious Puberty.

Cell Metab 2020 Dec 19;32(6):951-966.e8. Epub 2020 Oct 19.

Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), Department of Cell Biology, Physiology and Immunology, University of Córdoba and Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain; Research Centre for Integrative Physiology and Pharmacology, Institute of Biomedicine and Turku Center for Disease Modeling, University of Turku, Turku, Finland. Electronic address:

Childhood obesity, especially in girls, is frequently bound to earlier puberty, which is linked to higher disease burden later in life. The mechanisms underlying this association remain elusive. Here we show that brain ceramides participate in the control of female puberty and contribute to its alteration in early-onset obesity in rats. Postnatal overweight caused earlier puberty and increased hypothalamic ceramide content, while pharmacological activation of ceramide synthesis mimicked the pubertal advancement caused by obesity, specifically in females. Conversely, central blockade of de novo ceramide synthesis delayed puberty and prevented the effects of the puberty-activating signal, kisspeptin. This phenomenon seemingly involves a circuit encompassing the paraventricular nucleus (PVN) and ovarian sympathetic innervation. Early-onset obesity enhanced PVN expression of SPTLC1, a key enzyme for ceramide synthesis, and advanced the maturation of the ovarian noradrenergic system. In turn, obesity-induced pubertal precocity was reversed by virogenetic suppression of SPTLC1 in the PVN. Our data unveil a pathway, linking kisspeptin, PVN ceramides, and sympathetic ovarian innervation, as key for obesity-induced pubertal precocity.
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http://dx.doi.org/10.1016/j.cmet.2020.10.001DOI Listing
December 2020

Environmentally Relevant Perinatal Exposures to Bisphenol A Disrupt Postnatal Kiss1/NKB Neuronal Maturation and Puberty Onset in Female Mice.

Environ Health Perspect 2019 10 25;127(10):107011. Epub 2019 Oct 25.

Instituto Maimónides de Investigación Biomédica de Cordoba (IMIBIC), Department of Cell Biology, Physiology and Immunology, University of Cordoba, Avda, Cordoba, Spain.

Background: The timing of puberty is highly sensitive to environmental factors, including endocrine disruptors. Among them, bisphenol A (BPA) has been previously analyzed as potential modifier of puberty. Yet, disparate results have been reported, with BPA advancing, delaying, or being neutral in its effects on puberty onset. Likewise, mechanistic analyses addressing the central and peripheral actions/targets of BPA at puberty remain incomplete and conflictive.

Objective: We aimed to provide a comprehensive characterization of the impact of early BPA exposures, especially at low, real-life doses, on the postnatal development of hypothalamic Kiss1/NKB neurons, and its functional consequences on female pubertal maturation.

Methods: Pregnant CD1 female mice were orally administered BPA at 5, 10, or body weight (BW)/d from gestational day 11 to postnatal day 8 (PND8). Vaginal opening, as an external marker of puberty onset, was monitored daily from PND19 to PND30 in the female offspring. Blood and brain samples were collected at PND12, 15, 18, 21, and 30 for measuring circulating levels of gonadotropins and analyzing the hypothalamic expression of Kiss1/kisspeptin and NKB.

Results: Perinatal exposure to BPA, in a range of doses largely below the no observed adverse effect level (NOAEL; BW/d, according to the FDA), was associated with pubertal differences in the female progeny compared with those exposed to vehicle alone, with an earlier age of vaginal opening but consistently lower levels of circulating luteinizing hormone. Mice treated with BPA exhibited a persistent, but divergent, impairment of Kiss1 neuronal maturation, with more kisspeptin cells in the rostral (RP3V) hypothalamus but consistently fewer kisspeptin neurons in the arcuate nucleus (ARC). Detailed quantitative analysis of the ARC population, essential for pubertal development, revealed that mice treated with BPA had persistently lower Kiss1 expression during (pre)pubertal maturation, which was associated with lower Tac2 (encoding NKB) levels, even at low doses ( BW/d), in the range of the tolerable daily intake (TDI), recently updated by the European Food Safety Authority.

Conclusions: Our data attest to the consistent, but divergent, effects of gestational exposures to low concentrations of BPA, via the oral route, on phenotypic and neuroendocrine markers of puberty in female mice, with an unambiguous impact on the developmental maturation not only of Kiss1, but also of the NKB system, both essential regulators of puberty onset. https://doi.org/10.1289/EHP5570.
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http://dx.doi.org/10.1289/EHP5570DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6867420PMC
October 2019

Validation of the protein kinase CLK3 as a multistage cross-species malarial drug target.

Science 2019 08;365(6456)

Centre for Translational Pharmacology, Institute of Molecular Cell and Systems Biology, University of Glasgow, Glasgow G12 8QQ, UK.

The requirement for next-generation antimalarials to be both curative and transmission-blocking necessitates the identification of previously undiscovered druggable molecular pathways. We identified a selective inhibitor of the protein kinase CLK3, which we used in combination with chemogenetics to validate CLK3 as a drug target acting at multiple parasite life stages. Consistent with a role for CLK3 in RNA splicing, inhibition resulted in the down-regulation of more than 400 essential parasite genes. Inhibition of CLK3 mediated rapid killing of asexual liver- and blood-stage and blockade of gametocyte development, thereby preventing transmission, and also showed parasiticidal activity against and Hence, our data establish CLK3 as a target for drugs, with the potential to offer a cure-to be prophylactic and transmission blocking in malaria.
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http://dx.doi.org/10.1126/science.aau1682DOI Listing
August 2019

Inhibiting the stringent response blocks entry into quiescence and reduces persistence.

Sci Adv 2019 03 20;5(3):eaav2104. Epub 2019 Mar 20.

Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.

The stringent response enables () to shut down its replication and metabolism under various stresses. Here we show that lacking the stringent response enzyme Rel was unable to slow its replication rate during nutrient starvation. Metabolomics analysis revealed that the nutrient-starved -deficient strain had increased metabolism similar to that of exponentially growing wild-type bacteria in nutrient-rich broth, consistent with an inability to enter quiescence. Deficiency of increased the susceptibility of mutant bacteria to killing by isoniazid during nutrient starvation and in the lungs of chronically infected mice. We screened a pharmaceutical library of over 2 million compounds for inhibitors of Rel and showed that the lead compound X9 was able to directly kill nutrient-starved and enhanced the killing activity of isoniazid. Inhibition of Rel is a promising approach to target persisters, with the potential to shorten the duration of TB treatment.
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http://dx.doi.org/10.1126/sciadv.aav2104DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6426458PMC
March 2019

Metabolic regulation of female puberty via hypothalamic AMPK-kisspeptin signaling.

Proc Natl Acad Sci U S A 2018 11 22;115(45):E10758-E10767. Epub 2018 Oct 22.

Instituto Maimónides de Investigación Biomédica de Córdoba, 14004 Cordoba, Spain;

Conditions of metabolic distress, from malnutrition to obesity, impact, via as yet ill-defined mechanisms, the timing of puberty, whose alterations can hamper later cardiometabolic health and even life expectancy. AMP-activated protein kinase (AMPK), the master cellular energy sensor activated in conditions of energy insufficiency, has a major central role in whole-body energy homeostasis. However, whether brain AMPK metabolically modulates puberty onset remains unknown. We report here that central AMPK interplays with the puberty-activating gene, , to control puberty onset. Pubertal subnutrition, which delayed puberty, enhanced hypothalamic pAMPK levels, while activation of brain AMPK in immature female rats substantially deferred puberty. Virogenetic overexpression of a constitutively active form of AMPK, selectively in the hypothalamic arcuate nucleus (ARC), which holds a key population of Kiss1 neurons, partially delayed puberty onset and reduced luteinizing hormone levels. ARC Kiss1 neurons were found to express pAMPK, and activation of AMPK reduced ARC expression. The physiological relevance of this pathway was attested by conditional ablation of the AMPKα1 subunit in Kiss1 cells, which largely prevented the delay in puberty onset caused by chronic subnutrition. Our data demonstrate that hypothalamic AMPK signaling plays a key role in the metabolic control of puberty, acting via a repressive modulation of ARC Kiss1 neurons in conditions of negative energy balance.
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http://dx.doi.org/10.1073/pnas.1802053115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6233121PMC
November 2018

Intergenerational Influence of Paternal Obesity on Metabolic and Reproductive Health Parameters of the Offspring: Male-Preferential Impact and Involvement of Kiss1-Mediated Pathways.

Endocrinology 2018 02;159(2):1005-1018

Instituto Maimónides de Investigación Biomédica de Cordoba, University of Cordoba, Cordoba, Spain.

Obesity and its comorbidities are reaching epidemic proportions worldwide. Maternal obesity is known to predispose the offspring to metabolic disorders, independently of genetic inheritance. This intergenerational transmission has also been suggested for paternal obesity, with a potential negative impact on the metabolic and, eventually, reproductive health of the offspring, likely via epigenetic changes in spermatozoa. However, the neuroendocrine component of such phenomenon and whether paternal obesity sensitizes the offspring to the disturbances induced by high-fat diet (HFD) remain poorly defined. We report in this work the metabolic and reproductive impact of HFD in the offspring from obese fathers, with attention to potential sex differences and alterations of hypothalamic Kiss1 system. Lean and obese male rats were mated with lean virgin female rats; male and female offspring were fed HFD from weaning onward and analyzed at adulthood. The increases in body weight and leptin levels, but not glucose intolerance, induced by HFD were significantly augmented in the male, but not female, offspring from obese fathers. Paternal obesity caused a decrease in luteinizing hormone (LH) levels and exacerbated the drop in circulating testosterone and gene expression of its key biosynthetic enzymes caused by HFD in the male offspring. LH responses to central kisspeptin-10 administration were also suppressed in HFD males from obese fathers. In contrast, paternal obesity did not significantly alter gonadotropin levels in the female offspring fed HFD, although these females displayed reduced LH responses to kisspeptin-10. Our findings suggest that HFD-induced metabolic and reproductive disturbances are exacerbated by paternal obesity preferentially in males, whereas kisspeptin effects are affected in both sexes.
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http://dx.doi.org/10.1210/en.2017-00705DOI Listing
February 2018

Defining a novel leptin-melanocortin-kisspeptin pathway involved in the metabolic control of puberty.

Mol Metab 2016 Oct 11;5(10):844-857. Epub 2016 Aug 11.

Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia (HURS), 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 14004 Córdoba, Spain. Electronic address:

Objective: Puberty is a key developmental phenomenon highly sensitive to metabolic modulation. Worrying trends of changes in the timing of puberty have been reported in humans. These might be linked to the escalating prevalence of childhood obesity and could have deleterious impacts on later (cardio-metabolic) health, but their underlying mechanisms remain unsolved. The neuropeptide α-MSH, made by POMC neurons, plays a key role in energy homeostasis by mediating the actions of leptin and likely participates in the control of reproduction. However, its role in the metabolic regulation of puberty and interplay with kisspeptin, an essential puberty-regulating neuropeptide encoded by Kiss1, remain largely unknown. We aim here to unveil the potential contribution of central α-MSH signaling in the metabolic control of puberty by addressing its role in mediating the pubertal effects of leptin and its potential interaction with kisspeptin.

Methods: Using wild type and genetically modified rodent models, we implemented pharmacological studies, expression analyses, electrophysiological recordings, and virogenetic approaches involving DREADD technology to selectively inhibit Kiss1 neurons, in order to interrogate the physiological role of a putative leptin→α-MSH→kisspeptin pathway in the metabolic control of puberty.

Results: Stimulation of central α-MSH signaling robustly activated the reproductive axis in pubertal rats, whereas chronic inhibition of melanocortin receptors MC3/4R, delayed puberty, and prevented the permissive effect of leptin on puberty onset. Central blockade of MC3/4R or genetic elimination of kisspeptin receptors from POMC neurons did not affect kisspeptin effects. Conversely, congenital ablation of kisspeptin receptors or inducible, DREADD-mediated inhibition of arcuate nucleus (ARC) Kiss1 neurons resulted in markedly attenuated gonadotropic responses to MC3/4R activation. Furthermore, close appositions were observed between POMC fibers and ARC Kiss1 neurons while blockade of α-MSH signaling suppressed Kiss1 expression in the ARC of pubertal rats.

Conclusions: Our physiological, virogenetic, and functional genomic studies document a novel α-MSH→kisspeptin→GnRH neuronal signaling pathway involved in transmitting the permissive effects of leptin on pubertal maturation, which is relevant for the metabolic (and, eventually, pharmacological) regulation of puberty onset.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5034608PMC
http://dx.doi.org/10.1016/j.molmet.2016.08.003DOI Listing
October 2016

Discovery of Novel Inhibitors of the Tautomerase Activity of Macrophage Migration Inhibitory Factor (MIF).

J Biomol Screen 2016 Jun 1;21(5):446-58. Epub 2016 Mar 1.

Molecular Discovery Research, Centro de Investigación Básica, GSK, Madrid, Spain

Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine associated with multiple diseases, including neurodegenerative disorders. With the ultimate goal of providing novel chemotypes as starting points for development of disease-modifying therapeutics for neurodegeneration, we endeavored to screen the GSK compound collection for MIF inhibitors using a miniaturized, activity-based kinetic assay. The assay monitors the increase in absorbance at 320 nm resulting from keto-to-enol tautomerization of 4-hydroxyphenylpyruvate, a reaction catalyzed by MIF. We ran a full-diversity screen evaluating the inhibitory activity of 1.6 million compounds. Primary hits were confirmed and retested in an orthogonal assay measuring tautomerization of l-dopachrome methyl ester by the decrease in absorbance at 475 nm in kinetic mode. Selected compounds were progressed to medium-throughput mode-of-inhibition studies, which included time dependence, enzyme concentration dependence, and reversibility of their inhibitory effect. With these results and after inspection of the physicochemical properties of compounds, 17 chemotypes were prioritized and progressed to further stages of validation and characterization to better assess their therapeutic potential.
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http://dx.doi.org/10.1177/1087057116633997DOI Listing
June 2016

Interaction between neonatal maternal deprivation and serum leptin levels on metabolism, pubertal development, and sexual behavior in male and female rats.

Biol Sex Differ 2016 11;7. Epub 2016 Jan 11.

Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Avenida Menéndez Pelayo, 65, Madrid, 28009 Spain ; CIBEROBN, Instituto Carlos III Madrid, Madrid, Spain.

Background: Maternal deprivation (MD) during neonatal life can have long-term effects on metabolism and behavior, with males and females responding differently. We previously reported that MD during 24 h at postnatal day (PND) 9 blocks the physiological neonatal leptin surge in both sexes. It is known that modifications in neonatal leptin levels can affect metabolism in adulthood. Thus, we hypothesized that at least some of the long-term metabolic changes that occur in response to MD are due to the decline in serum leptin during this critical period of development. Hence, we predicted that treatment with leptin during MD would normalize these metabolic changes, with this response also differing between the sexes.

Methods: MD was carried-out in Wistar rats for 24 h on PND9. Control and MD rats of both sexes were treated from PND 9 to 13 with leptin (3 mg/kg/day sc) or vehicle. Weight gain, food intake, glucose tolerance, and pubertal onset were monitored. Sexual behavior was analyzed in males. Rats were killed at PND90, and serum hormones and hypothalamic neuropeptides involved in metabolic control and reproduction were measured. Results were analyzed by three-way analysis of covariance using sex, MD, and leptin treatment as factors and litter as the covariate and employing repeated measures where appropriate.

Results: In males, MD advanced the external signs of puberty and increased serum insulin and triglyceride levels and hypothalamic proopiomelanocortin mRNA levels at PND90. Neonatal leptin treatment normalized these effects. In contrast, MD decreased circulating triglycerides, as well as estradiol levels, in females at PND90 and these changes were also normalized by neonatal leptin treatment. Neonatal leptin treatment also had long-term effects in control rats as it advanced the external signs of puberty in control males, but delayed them in females. Neonatal leptin treatment increased serum insulin and hypothalamic mRNA levels of the leptin receptor and cocaine- and amphetamine-regulated transcript in control males and increased orexin mRNA levels in controls of both sexes. Although pubertal onset in males was advanced by either MD or neonatal leptin treatment in males and delayed by leptin treatment in females, the mRNA levels of hypothalamic neuropeptides and receptors related to reproduction were not affected by MD or neonatal leptin treatment in either sex at PND90.

Conclusions: These findings indicate that some of the long-term changes in metabolic and reproductive parameters induced by MD, such as advanced pubertal onset and increased hypothalamic proopiomelanocortin (POMC) expression, hyperinsulinemia, and hypertriglyceridemia in adult males and decreased serum triglyceride and estradiol levels in females, are most likely due to the decrease in leptin levels during the period of MD.
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http://dx.doi.org/10.1186/s13293-015-0054-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4710050PMC
January 2016

Blockage of the Neonatal Leptin Surge Affects the Gene Expression of Growth Factors, Glial Proteins, and Neuropeptides Involved in the Control of Metabolism and Reproduction in Peripubertal Male and Female Rats.

Endocrinology 2015 Jul 9;156(7):2571-81. Epub 2015 Apr 9.

Department of Physiology (Animal Physiology II) (V.M., A.B.L.-R., M.-P.V.), Faculty of Biology, Universidad Complutense, 28040 Madrid, Spain; Department of Endocrinology (F.D., J.A., J.A.C.), Hospital Infantil Universitario Niño Jesús, Department of Pediatrics, Universidad Autónoma de Madrid, Instituto de Investigación Sanitaria Princesa, 28009 Madrid, Spain; Centro de Investigación Biomédica en Red (CIBER) Fisiopatología de Obesidad y Nutrición (F.D., M.J.V., J.A., M.T.-S., J.A.C.), Instituto Carlos III, 28903 Madrid, Spain; Department of Cell Biology, Physiology, and Immunology (M.J.V., M.T.-S.), University of Córdoba and Instituto Maimónides de Investigación Biomédica, Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; and The Robert H. Smith Faculty of Agriculture, Food and Environment (A.G.), The Hebrew University of Jerusalem, Rehovot, Israel 76100.

Leptin (Lep) is important in the development of neuroendocrine circuits involved in metabolic control. Because both Lep and metabolism influence pubertal development, we hypothesized that early changes in Lep signaling could also modulate hypothalamic (HT) systems involved in reproduction. We previously demonstrated that a single injection of a Lep antagonist (Antag) on postnatal day (PND)9, coincident with the neonatal Lep peak, induced sexually dimorphic modifications in trophic factors and markers of cell turnover and neuronal maturation in the HT on PND13. Here, our aim was to investigate whether the alterations induced by Lep antagonism persist into puberty. Accordingly, male and female rats were treated with a pegylated super Lep Antag from PND5 to PND9 and killed just before the normal appearance of external signs of puberty (PND33 in females and PND43 in males). There was no effect on body weight, but in males food intake increased, subcutaneous adipose tissue decreased and HT neuropeptide Y and Agouti-related peptide mRNA levels were reduced, with no effect in females. In both sexes, the Antag increased HT mRNA levels of the kisspeptin receptor, G protein-coupled recepter 54 (Gpr54). Expression of the Lep receptor, trophic factors, and glial markers were differently affected in the HT of peripubertal males and females. Lep production in adipose tissue was decreased in Antag-treated rats of both sexes, with production of other cytokines being differentially regulated between sexes. In conclusion, in addition to the long-term effects on metabolism, changes in neonatal Lep levels modifies factors involved in reproduction that could possibly affect sexual maturation.
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http://dx.doi.org/10.1210/en.2014-1981DOI Listing
July 2015

Roles of leptin in reproduction, pregnancy and polycystic ovary syndrome: consensus knowledge and recent developments.

Metabolism 2015 Jan 23;64(1):79-91. Epub 2014 Oct 23.

Department of Cell Biology, Physiology and Immunology, University of Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Spain; Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC)/Hospital Universitario Reina Sofia, 14004 Córdoba, Spain. Electronic address:

As an essential function for perpetuation of species, reproduction, including puberty onset, is sensitive to the size of body energy stores and the metabolic state of the organism. Accordingly, impaired energy homeostasis, ranging from extreme leanness, such as in anorexia or cachexia, to morbid obesity has an impact on the timing of puberty and is often associated to fertility problems. The neuroendocrine basis for such phenomenon is the close connection between numerous metabolic hormones and nutritional cues with the various elements of the so-called hypothalamic-pituitary-gonadal (HPG) axis. Yet, despite previous fragmentary knowledge, it was only the discovery of the adipose-hormone, leptin, in 1994 what revolutionized our understanding on how metabolic and reproductive systems closely interplay and allowed the definition of the neurohormonal causes of perturbations of puberty and fertility in conditions of impaired body energy homeostasis. In this article, we aim to provide a synoptic view of the mechanisms whereby leptin engages in the regulation of different elements of the HPG axis, with special attention to its effects and mechanisms of action on the different elements of the reproductive brain and its proven direct effects in the gonads. In addition, we will summarize the state-of-the-art regarding the putative roles of leptin during gestation, including its potential function as placental hormone. Finally, comments will be made on the eventual leptin alterations in reproductive disorders, with special attention to the polycystic ovary syndrome (PCOS), a disease in which reproductive, metabolic and neuroendocrine alterations are commonly observed. All in all, we intend to provide an updated account of our knowledge on the physiological roles of leptin in the metabolic regulation of the reproductive axis and its eventual pathophysiological implications in prevalent reproductive disorders, such as PCOS.
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http://dx.doi.org/10.1016/j.metabol.2014.10.013DOI Listing
January 2015

Kinetic considerations on the development of binding assays in single-addition mode: application to the search for α2δ1 modulators.

J Biomol Screen 2012 Sep 5;17(8):1041-9. Epub 2012 Jul 5.

Biological Reagents and Assay Development Department, GlaxoSmithKline, Madrid, Spain.

The development of assays in single-addition mode is of great interest for screening purposes given the multiple advantages of minimizing the number of intervention steps. Binding assays seem to be more prone to this attractive format because no functional biological activity is taking place but instead a biophysical process, whose dynamics seem easier to control without introducing significant alterations, is happening. Therefore, single-addition assays based on the displacement of prebound labeled ligands can be conceived, but careful kinetic considerations must still be taken to maximize the sensitivity of the assay and to avoid jeopardizing the identification of compounds with slow-binding kinetics. This article shows the development of a single-addition, displacement-based binding assay intended to identify modulators that act by binding to the gabapentin site of the ion channel regulatory protein α2δ1. After studying the kinetics of gabapentin binding and the influence they might have on the assay sensitivity, the best conditions were identified, and the sensitivity was compared with that of the more classical two-additions competition-based assay. Although the present study focuses on α2δ1 and its interaction with gabapentin, the rationale and the methodology followed are of broad purpose and can be applied to virtually every binding assay.
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http://dx.doi.org/10.1177/1087057112452318DOI Listing
September 2012

[Antibiotic prescribing to the paediatric population of Castilla y León in the last decade: trends, seasonal fluctuations and geographical differences].

Rev Esp Quimioter 2012 Jun;25(2):139-46

Centro de Salud Arturo Eyries, C/ Puerto Rico s/n.47014, Valladolid, Spain.

Introduction: The development of antibiotic resistance is a danger to the health of the population, especially for children,due to low antimicrobial arsenal available to them.

Material And Methods: We performed a retrospective observational study referred to the prescriptions of systemic antibiotic in the paediatric population of Castilla y León in the years 2001 to 2010.

Results: The total use of antibiotics outside hospitals is around to 20.7 DID (defined daily dose per 1,000 inhabitants per day). There are two different phases: the first from 2001 to 2007 where there is an increase of consumption, with a peak of 25 DID in 2003, following a phase of decline, with a minimum of 18 DID in 2010. Broad-spectrum penicillins are the most used. We also observe changes in prescription trends. It has a clear seasonal prescription profile related to acute respiratory infections (ARI) of winter, stands in February. The use of antibiotics varies substantially between different Health Areas.

Conclusions: We observed a decrease in antibiotic prescription to children in the last three years. Changes in the prescription profile for amoxicillin and at the expense of greater spectrum antibacterial antibiotics indicate a better match to therapeutic guidelines in recent years. The variability found in different Health Areas suggests the need for improvement in the rational use of antibiotic, at least to some.
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June 2012

BMP8B increases brown adipose tissue thermogenesis through both central and peripheral actions.

Cell 2012 May;149(4):871-85

Metabolic Research Laboratories, Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, UK.

Thermogenesis in brown adipose tissue (BAT) is fundamental to energy balance and is also relevant for humans. Bone morphogenetic proteins (BMPs) regulate adipogenesis, and, here, we describe a role for BMP8B in the direct regulation of thermogenesis. BMP8B is induced by nutritional and thermogenic factors in mature BAT, increasing the response to noradrenaline through enhanced p38MAPK/CREB signaling and increased lipase activity. Bmp8b(-/-) mice exhibit impaired thermogenesis and reduced metabolic rate, causing weight gain despite hypophagia. BMP8B is also expressed in the hypothalamus, and Bmp8b(-/-) mice display altered neuropeptide levels and reduced phosphorylation of AMP-activated protein kinase (AMPK), indicating an anorexigenic state. Central BMP8B treatment increased sympathetic activation of BAT, dependent on the status of AMPK in key hypothalamic nuclei. Our results indicate that BMP8B is a thermogenic protein that regulates energy balance in partnership with hypothalamic AMPK. BMP8B may offer a mechanism to specifically increase energy dissipation by BAT.
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http://dx.doi.org/10.1016/j.cell.2012.02.066DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3383997PMC
May 2012

Olanzapine, but not aripiprazole, weight-independently elevates serum triglycerides and activates lipogenic gene expression in female rats.

Int J Neuropsychopharmacol 2012 Mar 19;15(2):163-79. Epub 2011 Aug 19.

Dr. Einar Martens' Research Group for Biological Psychiatry, Department of Clinical Medicine, University of Bergen, Norway.

Metabolic adverse effects such as weight gain and dyslipidaemia represent a major concern in treatment with several antipsychotic drugs, including olanzapine. It remains unclear whether such metabolic side-effects fully depend on appetite-stimulating actions, or whether some dysmetabolic features induced by antipsychotics may arise through direct perturbation of metabolic pathways in relevant peripheral tissues. Recent clinical and preclinical studies indicate that dyslipidaemia could occur independently of weight gain. Using a rat model, we showed that subchronic treatment with olanzapine induces weight gain and increases adipose tissue mass in rats with free access to food. This effect was also observed for aripiprazole, considered metabolically neutral in the clinical setting. In pair-fed rats with limited food access, neither olanzapine nor aripiprazole induced weight gain. Interestingly, olanzapine, but not aripiprazole, induced weight-independent elevation of serum triglycerides, accompanied by up-regulation of several genes involved in lipid biosynthesis, both in liver and in adipose tissues. Our findings support the existence of tissue-specific, weight-independent direct effects of olanzapine on lipid metabolism.
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http://dx.doi.org/10.1017/S1461145711001271DOI Listing
March 2012

Acute effects of orexigenic antipsychotic drugs on lipid and carbohydrate metabolism in rat.

Psychopharmacology (Berl) 2012 Feb 12;219(3):783-94. Epub 2011 Jul 12.

Dr. Einar Martens' Research Group for Biological Psychiatry, Department of Clinical Medicine, University of Bergen, Bergen, Norway.

Objective: This study aims to investigate whether orexigenic antipsychotic drugs may induce dyslipidemia and glucose disturbances in female rats through direct perturbation of metabolically active peripheral tissues, independent of prior weight gain.

Methods: In the current study, we examined whether a single intraperitoneal injection of clozapine or olanzapine induced metabolic disturbances in adult female outbred Sprague-Dawley rats. Serum glucose and lipid parameters were measured during time-course experiments up to 48 h. Real-time quantitative PCR was used to measure specific transcriptional alterations in lipid and carbohydrate metabolism in adipose tissue depots or in the liver.

Results: Our results demonstrated that acute administration of clozapine or olanzapine induced a rapid, robust elevation of free fatty acids and glucose in serum, followed by hepatic accumulation of lipids evident after 12-24 h. These metabolic disturbances were associated with biphasic patterns of gluconeogenic and lipid-related gene expression in the liver and in white adipose tissue depots.

Conclusion: Our results support that clozapine and olanzapine are associated with primary effects on carbohydrate and lipid metabolism associated with transcriptional changes in metabolically active peripheral tissues prior to the development of drug-induced weight gain.
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http://dx.doi.org/10.1007/s00213-011-2397-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3259403PMC
February 2012

Olanzapine-induced hyperphagia and weight gain associate with orexigenic hypothalamic neuropeptide signaling without concomitant AMPK phosphorylation.

PLoS One 2011 13;6(6):e20571. Epub 2011 Jun 13.

Dr. Einar Martens' Research Group for Biological Psychiatry, Department of Clinical Medicine, University of Bergen, Bergen, Norway.

The success of antipsychotic drug treatment in patients with schizophrenia is limited by the propensity of these drugs to induce hyperphagia, weight gain and other metabolic disturbances, particularly evident for olanzapine and clozapine. However, the molecular mechanisms involved in antipsychotic-induced hyperphagia remain unclear. Here, we investigate the effect of olanzapine administration on the regulation of hypothalamic mechanisms controlling food intake, namely neuropeptide expression and AMP-activated protein kinase (AMPK) phosphorylation in rats. Our results show that subchronic exposure to olanzapine upregulates neuropeptide Y (NPY) and agouti related protein (AgRP) and downregulates proopiomelanocortin (POMC) in the arcuate nucleus of the hypothalamus (ARC). This effect was evident both in rats fed ad libitum and in pair-fed rats. Of note, despite weight gain and increased expression of orexigenic neuropeptides, subchronic administration of olanzapine decreased AMPK phosphorylation levels. This reduction in AMPK was not observed after acute administration of either olanzapine or clozapine. Overall, our data suggest that olanzapine-induced hyperphagia is mediated through appropriate changes in hypothalamic neuropeptides, and that this effect does not require concomitant AMPK activation. Our data shed new light on the hypothalamic mechanism underlying antipsychotic-induced hyperphagia and weight gain, and provide the basis for alternative targets to control energy balance.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0020571PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3113797PMC
November 2011

High-yield production and characterization of biologically active GST-tagged human topoisomerase IIα protein in insect cells for the development of a high-throughput assay.

Protein Expr Purif 2011 Apr 13;76(2):165-72. Epub 2010 Aug 13.

Biological Reagents & Assay Development, GlaxoSmithKline R&D, New Frontiers Science Park, Harlow, Essex, UK.

DNA topoisomerase type II enzymes are well-validated targets of anti-bacterial and anti-cancer compounds. In order to facilitate discovery of these types of inhibitors human topoisomerase II in vitro assays can play an important role to support drug discovery processes. Typically, human topoisomerase IIα proteins have been purified from human cell lines or as untagged proteins from yeast cells. This study reports a method for the rapid over-expression and purification of active GST-tagged human topoisomerase IIα using the baculovirus mediated insect cell expression system. Expression of the GST fused protein was observed in the nuclear fraction of insect cells. High yields (40 mg/L i.e. 8 mg/10(9) cells) at >80% purity of this target was achieved by purification using a GST HiTrap column followed by size exclusion chromatography. Functional activity of GST-tagged human topoisomerase IIα was demonstrated by ATP-dependent relaxation of supercoiled DNA in an agarose gel based assay. An 8-fold DNA-dependent increase in ATPase activity of this target compared to its intrinsic activity was also demonstrated in a high-throughput ATPase fluorescence based assay. Human topoisomerase IIα inhibitors etoposide, quercetin and suramin were tested in the fluorescence assay. IC(50) values obtained were in good agreement with published data. These inhibitors also demonstrated ≥ 30-fold potency over the anti-bacterial topoisomerase II inhibitor ciprofloxacin in the assay. Collectively these data validated the enzyme and the high-throughput fluorescence assay as tools for inhibitor identification and selectivity studies.
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http://dx.doi.org/10.1016/j.pep.2010.08.001DOI Listing
April 2011

Extracellular fatty acid synthase: a possible surrogate biomarker of insulin resistance.

Diabetes 2010 Jun 18;59(6):1506-11. Epub 2010 Mar 18.

Department of Diabetes, Endocrinology and Nutrition, Institutd' Investigació Biomédica de Girona, CIBEROBN Fisiopatología de la Obesidad y Nutrición CB06/03/010, Girona, Catalonia, Spain.

Context: Circulating fatty acid synthase (FASN) is a biomarker of metabolically demanding human diseases. The aim of this study was to determine whether circulating FASN could be a biomarker of overnutrition-induced metabolic stress and insulin resistance in common metabolic disorders.

Research Design And Methods: Circulating FASN was evaluated in two cross-sectional studies in association with insulin sensitivity and in four longitudinal studies investigating the effect of diet- and surgery-induced weight loss, physical training, and adipose tissue expansion using peroxisome proliferator-activated receptor agonist rosiglitazone on circulating FASN.

Results: Age- and BMI-adjusted FASN concentrations were significantly increased in association with obesity-induced insulin resistance in two independent cohorts. Both visceral and subcutaneous FASN expression and protein levels correlated inversely with extracellular circulating FASN (P = -0.63; P < 0.0001), suggesting that circulating FASN is linked to depletion of intracellular FASN. Improved insulin sensitivity induced by therapeutic strategies that decreased fat mass (diet induced, surgery induced, or physical training) all led to decreased FASN levels in blood (P values between 0.02 and 0.04). To discriminate whether this was an effect related to insulin sensitization, we also investigated the effects of rosiglitazone. Rosiglitazone did not lead to significant changes in circulating FASN concentration.

Conclusions: Our results suggest that circulating FASN is a biomarker of overnutrition-induced insulin resistance that could provide diagnostic and prognostic advantages by providing insights on the individualized metabolic stress.
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http://dx.doi.org/10.2337/db09-1756DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2874712PMC
June 2010

Resistin: regulation of food intake, glucose homeostasis and lipid metabolism.

Endocr Dev 2010 24;17:175-184. Epub 2009 Nov 24.

Resistin has been identified as a hormone secreted by adipocytes that is under hormonal and nutritional control. This hormone has been suggested to be the link between obesity and type 2 diabetes. In rodents, resistin is mainly located and secreted from adipocytes, even though its expression was also found in several other tissues. However, in humans resistin is expressed primarily by macrophages and seems to be involved in the recruitment of other immune cells and the secretion of pro-inflammatory factors, although its role in insulin resistance cannot be ruled out. In addition to its role in glucose metabolism, resistin has been also involved in the control of hypothalamic and peripheral lipid metabolism and in the regulation of food intake. In this short review, we will summarize the most relevant findings of this hormone in rodents.
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http://dx.doi.org/10.1159/000262538DOI Listing
December 2010

Adiponectin receptor 2 is regulated by nutritional status, leptin and pregnancy in a tissue-specific manner.

Physiol Behav 2010 Jan;99(1):91-9

Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, 15782 Santiago de Compostela, Spain.

The aim of the present work was to study the regulation of circulating adiponectin levels and the expression of adiponectin receptor 2 (Adipo-R2) in several rat tissues in relation to fasting, leptin challenge, pregnancy, and chronic undernutrition. Using real-time PCR, we found Adipo-R2 mRNA expression in the liver, stomach, white and brown adipose tissues (WAT and BAT) of adult rats. Immunohistochemical studies confirmed protein expression in the same tissues. Adipo-R2 mRNA levels were decreased in liver after fasting, with no changes in the other tissues. Leptin decreased Adipo-R2 expression in liver and stomach, but increased its expression in WAT and BAT. Chronic caloric restriction in normal rats increased Adipo-R2 gene expression in stomach, while it decreased hepatic Adipo-R2 levels in pregnant rats. Using radioimmunoassay, we found that plasma adiponectin levels were diminished by fasting and leptin. Conversely, circulating adiponectin was increased in food-restricted rats, whereas its levels decreased in food-restricted pregnant rats by the end of gestation. In conclusion our findings provide the first evidence that (a) Adipo-R2 mRNA is regulated in a tissue-specific manner by fasting, but leptin is not responsible for those changes; (b) chronic caloric restriction in normal and pregnant rats also regulate Adipo-R2 mRNA in a tissue-specific manner; and (c) Adipo-R2 mRNA does not show a clear correlation with plasma adiponectin levels.
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http://dx.doi.org/10.1016/j.physbeh.2009.10.015DOI Listing
January 2010

Discovery of GSK837149A, an inhibitor of human fatty acid synthase targeting the beta-ketoacyl reductase reaction.

FEBS J 2008 Apr 25;275(7):1556-67. Epub 2008 Feb 25.

GlaxoSmithKline R&D, Biological Reagents and Assay Development Department, Centro de Investigación Básica, Tres Cantos, Spain.

GSK837149A has been identified as a selective inhibitor of human fatty acid synthase (FAS). The compound was first isolated as a minor impurity in a sample found to be active against the enzyme in a high-throughput screening campaign. The structure of this compound was confirmed by NMR and MS studies, and evaluation of the newly synthesized molecule confirmed its activity against FAS. The compound and other analogs synthesized, all being symmetrical structures containing a bisulfonamide urea, act by inhibiting the beta-ketoacyl reductase activity of the enzyme. GSK837149A inhibits FAS in a reversible mode, with a K(i) value of approximately 30 nm, and it possibly binds to the enzyme-ketoacyl-ACP complex. Although initial results suggest that cell penetration for these compounds is impaired, they still can be regarded as useful tools with which to probe and explore the beta-ketoacyl reductase active site in FAS, helping in the design of new inhibitors.
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http://dx.doi.org/10.1111/j.1742-4658.2008.06314.xDOI Listing
April 2008

Utilization of substrate-induced quenching for screening targets promoting NADH and NADPH consumption.

J Biomol Screen 2006 Feb 16;11(1):75-81. Epub 2005 Dec 16.

Assay Development, Glaxo SmithKline, Madrid, Spain.

Oxidation of reduced nicotinamide adenine dinucleotides is a common event for many biochemical reactions. However, its exploitation for ultrahigh-throughput screening purposes is not an easy task and is affected by various drawbacks. It is known that such nucleotides induce quenching on the fluorescence of several dyes and that this quenching disappears with oxidation of the nucleotide. We have made use of this property to develop an assay for high-throughput screening with NADH and NADPH-dependent reductases. Full screening campaigns have been run with excellent assay quality parameters, and interesting hits have been identified. The method is amenable to miniaturization and allows easy identification of false positives without needing extra secondary assays. Although it is based on monitoring substrate consumption, it is demonstrated that the effect of fractional conversion on assay sensitivity is negligible.
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http://dx.doi.org/10.1177/1087057105283296DOI Listing
February 2006

Central administration of resistin promotes short-term satiety in rats.

Eur J Endocrinol 2005 Sep;153(3):R1-5

Department of Physiology, University of Santiago de Compostela, Santiago de Compostela 15 782, Spain.

Objective: Several hormones expressed in white adipose tissue influence food intake at the central level. We sought to determine whether resistin, a circulating adipose-derived hormone in rodents, has actions on the hypothalamus by determining the effects of central resistin injection on food intake and on hypothalamic Fos protein expression.

Design: As resistin expression in adipose tissue is influenced by altered nutritional status, we studied the effect of central resistin in both fed and pre-fasted rats.

Results: In fasted rats, central injection of resistin decreased food intake acutely and increased the number of cells that express Fos protein in the arcuate nucleus but not in any other hypothalamic structure. The effect on food intake was dose-dependent and did not result in the formation of a conditioned taste aversion.

Conclusions: Taken together, these results provide the first evidence documenting a central action of resistin, which could be involved in a feedback loop targeting the hypothalamus. On the other hand, since we observed resistin mRNA in the arcuate and ventromedial nuclei of the hypothalamus, it is also possible that brain-derived resistin serves as a neuropeptide involved in the regulation of energy homeostasis. However, since resistin-induced satiety was modest and transient, as central administration for several days did not affect body weight, the physiological relevance and therapeutic potential of the observed principal phenomenon may be limited.
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http://dx.doi.org/10.1530/eje.1.01999DOI Listing
September 2005

Sensing the fat: fatty acid metabolism in the hypothalamus and the melanocortin system.

Peptides 2005 Oct;26(10):1753-8

Department of Physiology, School of Medicine, University of Santiago de Compostela, C/S. Francisco 1, 15705 Santiago de Compostela, Spain.

Recent evidence has demonstrated that circulating long chain fatty acids act as nutrient abundance signals in the hypothalamus. Moreover, pharmacological inhibition of fatty acid synthase (FAS) results in profound decrease in food intake and body weight in rodents. These anorectic actions are mediated by the modulation of hypothalamic neuropeptide systems, such as melanocortins. In this review, we summarize what is known about lipid sensing and fatty acid metabolism in the hypothalamus. Understanding these molecular mechanisms could provide new pharmacological targets for the treatment of obesity and appetite disorders, as well as novel concepts in the nutritional design.
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http://dx.doi.org/10.1016/j.peptides.2004.11.025DOI Listing
October 2005