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1.
Metabolism ; 115: 154460, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33285180

RESUMO

BACKGROUND: Reproduction is tightly coupled to body energy and metabolic status. GnRH neurons, master elements and final output pathway for the brain control of reproduction, directly or indirectly receive and integrate multiple metabolic cues to regulate reproductive function. Yet, the molecular underpinnings of such phenomenon remain largely unfolded. AMP-activated protein kinase (AMPK), the fundamental cellular sensor that becomes activated in conditions of energy deficit, has been recently shown to participate in the control of Kiss1 neurons, essential gatekeepers of the reproductive axis, by driving an inhibitory valence in situations of energy scarcity at puberty. However, the contribution of AMPK signaling specifically in GnRH neurons to the metabolic control of reproduction remains unknown. METHODS: Double immunohistochemistry (IHC) was applied to evaluate expression of active (phosphorylated) AMPK in GnRH neurons and a novel mouse line, named GAMKO, with conditional ablation of the AMPK α1 subunit in GnRH neurons, was generated. GAMKO mice of both sexes were subjected to reproductive characterization, with attention to puberty and gonadotropic responses to kisspeptin and metabolic stress. RESULTS: A vast majority (>95%) of GnRH neurons co-expressed pAMPK. Female (but not male) GAMKO mice displayed earlier puberty onset and exaggerated LH (as surrogate marker of GnRH) responses to kisspeptin-10 at the prepubertal age. In adulthood, GAMKO females retained increased LH responsiveness to kisspeptin and showed partial resilience to the inhibitory effects of conditions of negative energy balance on the gonadotropic axis. The modulatory role of AMPK in GnRH neurons required preserved ovarian function, since the differences in LH pulsatility detected between GAMKO and control mice subjected to fasting were abolished in ovariectomized animals. CONCLUSIONS: Altogether, our data document a sex-biased, physiological role of AMPK signaling in GnRH neurons, as molecular conduit of the inhibitory actions of conditions of energy deficit on the female reproductive axis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Metabolismo Energético/fisiologia , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Luteinizante/sangue , Neurônios/metabolismo , Reprodução/fisiologia , Proteínas Quinases Ativadas por AMP/genética , Animais , Ciclo Estral/metabolismo , Feminino , Kisspeptinas/farmacologia , Masculino , Desnutrição/metabolismo , Camundongos , Camundongos Knockout , Neurônios/efeitos dos fármacos , Fosforilação , Caracteres Sexuais , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
2.
Talanta ; 219: 121184, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887102

RESUMO

Matrix-assisted laser desorption ionization (MALDI) imaging mass spectrometry (IMS) is increasingly recognized for its potential in the discovery of novel biomarkers directly from tissue sections. However, there are no MALDI IMS studies as yet on the adipose tissue, a lipid-enriched tissue that plays a pivotal role in the development of obesity-associated disorders. Herein, we aimed at developing an optimized method for analyzing adipose tissue lipid composition under both physiological and pathological conditions by MALDI IMS. Our studies showed an exacerbated lipid delocalization from adipose tissue sections when conventional strategies were applied. However, our optimized method using conductive-tape sampling and 2,5-dihydroxybenzoic acid (DHB) as a matrix, preserved the anatomical organization and minimized lipid diffusion from sample sections. This method enabled the identification of a total of 625 down-regulated and 328 up-regulated m/z values in the adipose tissue from a rat model of extreme obesity as compared to lean animals. Combination of MALDI IMS and liquid chromatography (LC)-MS/MS data identified 44 differentially expressed lipid species between lean and obese animals, including phospholipids and sphingomyelins. Among the lipids identified, SM(d18:0_18:2), PE(P-16:0_20:0), and PC(O-16:0_16:1) showed a differential spatial distribution in the adipose tissue of lean vs. obese animals. In sum, our method provides a valuable new tool for research on adipose tissue that may pave the way for the identification of novel biomarkers of obesity and metabolic disease.


Assuntos
Fosfolipídeos , Espectrometria de Massas em Tandem , Tecido Adiposo , Animais , Cromatografia Líquida , Ratos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
3.
Sci Rep ; 10(1): 13898, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807904

RESUMO

In addition to its essential role in the physiological control of longitudinal growth, growth-hormone (GH) is endowed with relevant metabolic functions, including anabolic actions in muscle, lipolysis in adipose-tissue and glycemic modulation. Adult obesity is known to negatively impact GH-axis, thereby promoting a vicious circle that may contribute to the exacerbation of the metabolic complications of overweight. Yet, to what extent early-overnutrition sensitizes the somatotropic-axis to the deleterious effects of obesity remains largely unexplored. Using a rat-model of sequential exposure to obesogenic insults, namely postnatal-overfeeding during lactation and high-fat diet (HFD) after weaning, we evaluated in both sexes the individual and combined impact of these nutritional challenges upon key elements of the somatotropic-axis. While feeding HFD per se had a modest impact on the adult GH-axis, early overnutrition had durable effects on key elements of the somatotropic-system, which were sexually different, with a significant inhibition of pituitary gene expression of GH-releasing hormone-receptor (GHRH-R) and somatostatin receptor-5 (SST5) in males, but an increase in pituitary GHRH-R, SST2, SST5, GH secretagogue-receptor (GHS-R) and ghrelin expression in females. Notably, early-overnutrition sensitized the GH-axis to the deleterious impact of HFD, with a significant suppression of pituitary GH expression in both sexes and lowering of circulating GH levels in females. Yet, despite their similar metabolic perturbations, males and females displayed rather distinct alterations of key somatotropic-regulators/ mediators. Our data document a synergistic effect of postnatal-overnutrition on the detrimental impact of HFD-induced obesity on key elements of the adult GH-axis, which is conducted via mechanisms that are sexually-divergent.


Assuntos
Dieta Hiperlipídica , Hormônio do Crescimento/metabolismo , Obesidade/etiologia , Hipernutrição/complicações , Caracteres Sexuais , Animais , Peso Corporal , Feminino , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Modelos Biológicos , Obesidade/genética , Especificidade de Órgãos , Hipernutrição/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Wistar , Receptores da Somatotropina/genética , Receptores da Somatotropina/metabolismo
4.
Hum Reprod ; 34(12): 2495-2512, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31820802

RESUMO

STUDY QUESTION: Can kisspeptin treatment induce gonadotrophin responses and ovulation in preclinical models and anovulatory women with polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: Kisspeptin administration in some anovulatory preclinical models and women with PCOS can stimulate reproductive hormone secretion and ovulation, albeit with incomplete efficacy. WHAT IS KNOWN ALREADY: PCOS is a prevalent, heterogeneous endocrine disorder, characterized by ovulatory dysfunction, hyperandrogenism and deregulated gonadotrophin secretion, in need of improved therapeutic options. Kisspeptins (encoded by Kiss1) are master regulators of the reproductive axis, acting mainly at GnRH neurons, with kisspeptins being an essential drive for gonadotrophin-driven ovarian follicular maturation and ovulation. Altered Kiss1 expression has been found in rodent models of PCOS, although the eventual pathophysiological role of kisspeptins in PCOS remains unknown. STUDY DESIGN, SIZE, DURATION: Gonadotrophin and ovarian/ovulatory responses to kisspeptin-54 (KP-54) were evaluated in three preclinical models of PCOS, generated by androgen exposures at different developmental windows, and a pilot exploratory cohort of anovulatory women with PCOS. PARTICIPANTS/MATERIALS, SETTING, METHODS: Three models of PCOS were generated by exposure of female rats to androgens at different periods of development: PNA (prenatal androgenization; N = 20), NeNA (neonatal androgenization; N = 20) and PWA (post-weaning androgenization; N = 20). At adulthood (postnatal day 100), rats were subjected to daily treatments with a bolus of KP-54 (100 µg/kg, s.c.) or vehicle for 11 days (N = 10 per model and treatment). On Days 1, 4, 7 and 11, LH and FSH responses were assessed at different time-points within 4 h after KP-54 injection, while ovarian responses, in terms of follicular maturation and ovulation, were measured at the end of the treatment. In addition, hormonal (gonadotrophin, estrogen and inhibin B) and ovulatory responses to repeated KP-54 administration, at doses of 6.4-12.8 nmol/kg, s.c. bd for 21 days, were evaluated in a pilot cohort of anovulatory women (N = 12) diagnosed with PCOS, according to the Rotterdam criteria. MAIN RESULTS AND THE ROLE OF CHANCE: Deregulated reproductive indices were detected in all PCOS models: PNA, NeNA and PWA. Yet, anovulation was observed only in NeNA and PWA rats. However, while anovulatory NeNA rats displayed significant LH and FSH responses to KP-54 (P < 0.05), which rescued ovulation, PWA rats showed blunted LH secretion after repeated KP-54 injection and failed to ovulate. In women with PCOS, KP-54 resulted in a small rise in LH (P < 0.05), with an equivalent elevation in serum estradiol levels (P < 0.05). Two women showed growth of a dominant follicle with subsequent ovulation, one woman displayed follicle growth but not ovulation and desensitization was observed in another patient. No follicular response was detected in the other women. LIMITATIONS, REASONS FOR CAUTION: While three different preclinical PCOS models were used in order to capture the heterogeneity of clinical presentations of the syndrome, it must be noted that rat models recapitulate many but not all the features of this condition. Additionally, our pilot study was intended as proof of principle, and the number of participants is low, but the convergent findings in preclinical and clinical studies reinforce the validity of our conclusions. WIDER IMPLICATIONS OF THE FINDINGS: Our first-in-rodent and -human studies demonstrate that KP-54 administration in anovulatory preclinical models and women with PCOS can stimulate reproductive hormone secretion and ovulation, albeit with incomplete efficacy. As our rat models likely reflect the diversity of PCOS phenotypes, our results argue for the need of personalized management of anovulatory dysfunction in women with PCOS, some of whom may benefit from kisspeptin-based treatments. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by research agreements between Ferring Research Institute and the Universities of Cordoba and Edinburgh. K.S. was supported by the Wellcome Trust Scottish Translational Medicine and Therapeutics Initiative (STMTI). Some of this work was undertaken in the MRC Centre for Reproductive Health which is funded by the MRC Centre grant MR/N022556/1. M.T.-S. is a member of CIBER Fisiopatología de la Obesidad y Nutrición, which is an initiative of Instituto de Salud Carlos III. Dr Mannaerts is an employee of Ferring International PharmaScience Center (Copenhagen, Denmark), and Drs Qi, van Duin and Kohout are employees of the Ferring Research Institute (San Diego, USA). Dr Anderson and Dr Tena-Sempere were recipients of a grant support from the Ferring Research Institute, and Dr Anderson has undertaken consultancy work and received speaker fees outside this study from Merck, IBSA, Roche Diagnostics, NeRRe Therapeutics and Sojournix Inc. Dr Skorupskaite was supported by the Wellcome Trust through the Scottish Translational Medicine and Therapeutics Initiative 102419/Z/13/A. The other authors have no competing interest.


Assuntos
Kisspeptinas/uso terapêutico , Ovulação/efeitos dos fármacos , Síndrome do Ovário Policístico/tratamento farmacológico , Adulto , Animais , Modelos Animais de Doenças , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Kisspeptinas/farmacologia , Hormônio Luteinizante/sangue , Projetos Piloto , Síndrome do Ovário Policístico/sangue , Ratos Wistar , Adulto Jovem
5.
J Endocrinol ; 242(2): R51-R65, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31189134

RESUMO

Puberty is driven by sophisticated neuroendocrine networks that timely activate the brain centers governing the reproductive axis. The timing of puberty is genetically determined; yet, puberty is also sensitive to numerous internal and external cues, among which metabolic/nutritional signals are especially prominent. Compelling epidemiological evidence suggests that alterations of the age of puberty are becoming more frequent; the underlying mechanisms remain largely unknown, but the escalating prevalence of obesity and other metabolic/feeding disorders is possibly a major contributing factor. This phenomenon may have clinical implications, since alterations in pubertal timing have been associated to adverse health outcomes, including higher risk of earlier all-cause mortality. This urges for a better understanding of the neurohormonal basis of normal puberty and its deviations. Compelling evidence has recently documented the master role of hypothalamic neurons producing kisspeptins, encoded by Kiss1, in the neuroendocrine pathways controlling puberty. Kiss1 neurons seemingly participate in transmitting the regulatory actions of metabolic cues on pubertal maturation. Key cellular metabolic sensors, as the mammalian target of rapamycin (mTOR), AMP-activated protein kinase (AMPK) and the fuel-sensing deacetylase, SIRT1, have been recently shown to participate also in the metabolic modulation of puberty. Recently, we have documented that AMPK and SIRT1 operate as major molecular effectors for the metabolic control of Kiss1 neurons and, thereby, puberty onset. Alterations of these molecular pathways may contribute to the perturbation of pubertal timing linked to conditions of metabolic stress in humans, such as subnutrition or obesity and might become druggable targets for better management of pubertal disorders.


Assuntos
Metabolismo Energético/fisiologia , Desnutrição/fisiopatologia , Obesidade/fisiopatologia , Puberdade/fisiologia , Maturidade Sexual/fisiologia , Animais , Feminino , Humanos , Hipotálamo/fisiologia , Sistemas Neurossecretores/fisiologia
6.
Rev Clin Esp (Barc) ; 219(7): 390-393, 2019 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30902426

RESUMO

OBJECTIVE: To assess the frequency of care in an emergency department in the 6months prior to the diagnosis of tuberculosis and to determine the reasons for the care, the degree of suspicion in the emergency department and the factors associated with this suspicion. METHOD: A retrospective study was conducted on patients with pulmonary tuberculosis treated in the general emergency department between 2011 and 2017. RESULTS: Of the 54 included patients, 38 (70%) had been treated in the emergency department in the 6months prior to the diagnosis: 6 (16%) patients had been treated for processes unrelated to the tuberculosis, and 32 (84%) were treated for processes that were potentially related to the tuberculosis. Pulmonary tuberculosis was suspected in the emergency department for 12 (38%) of these patients and not suspected in the remaining 20 patients (62%). The group in which pulmonary tuberculosis was suspected had a higher rate of general and respiratory symptoms and cavitation in the radiography. CONCLUSIONS: A high percentage of patients with pulmonary tuberculosis were admitted to the emergency department in the 6months prior to the diagnosis, and this diagnostic possibility was often not suspected.

7.
Nat Commun ; 9(1): 4194, 2018 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-30305620

RESUMO

Puberty is regulated by epigenetic mechanisms and is highly sensitive to metabolic and nutritional cues. However, the epigenetic pathways mediating the effects of nutrition and obesity on pubertal timing are unknown. Here, we identify Sirtuin 1 (SIRT1), a fuel-sensing deacetylase, as a molecule that restrains female puberty via epigenetic repression of the puberty-activating gene, Kiss1. SIRT1 is expressed in hypothalamic Kiss1 neurons and suppresses Kiss1 expression. SIRT1 interacts with the Polycomb silencing complex to decrease Kiss1 promoter activity. As puberty approaches, SIRT1 is evicted from the Kiss1 promoter facilitating a repressive-to-permissive switch in chromatin landscape. Early-onset overnutrition accelerates these changes, enhances Kiss1 expression and advances puberty. In contrast, undernutrition raises SIRT1 levels, protracts Kiss1 repression and delays puberty. This delay is mimicked by central pharmacological activation of SIRT1 or SIRT1 overexpression, achieved via transgenesis or virogenetic targeting to the ARC. Our results identify SIRT1-mediated inhibition of Kiss1 as key epigenetic mechanism by which nutritional cues and obesity influence mammalian puberty.


Assuntos
Epigênese Genética , Kisspeptinas/genética , Fenômenos Fisiológicos da Nutrição , Obesidade/metabolismo , Maturidade Sexual , Sirtuína 1/metabolismo , Animais , Núcleo Arqueado do Hipotálamo/metabolismo , Cromatina/metabolismo , Feminino , Histonas/metabolismo , Hipotálamo/metabolismo , Kisspeptinas/metabolismo , Camundongos Transgênicos , Modelos Biológicos , Neurônios/metabolismo , Estado Nutricional , Complexo Repressor Polycomb 2/metabolismo , Regiões Promotoras Genéticas , Ratos , Ratos Wistar , Fatores de Tempo
8.
Hum Reprod ; 33(4): 680-689, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29401296

RESUMO

STUDY QUESTION: Is keratin 8/18 (K8/K18) expression linked to cell death/survival events in the human granulosa cell lineage? SUMMARY ANSWER: A close association exists between changes in K8/K18 expression and cell death/survival events along the human granulosa cell lineage lifespan. WHAT IS KNOWN ALREADY: In addition to their structural and mechanical functions, K8/K18 play essential roles regulating cell death, survival and differentiation in several non-gonadal epithelial tissues. Transfection of the granulosa-like tumor KGN cells with siRNA to interfere KRT8 and KRT18 expression increases FAS-mediated apoptosis, while an inverse association between K8/K18 expression and cell death has been found in the bovine antral follicles and corpus luteum. Yet, only fragmentary and inconclusive information exists regarding K8/K18 expression in the human ovary. STUDY DESIGN, SIZE, DURATION: Expression of K8/K18 was assessed by immunohistochemistry at different stages of the granulosa cell lineage, from flattened granulosa cells in primordial follicles to fully luteinized granulosa-lutein cells in the corpus luteum (including corpus luteum of pregnancy). PARTICIPANTS/MATERIALS, SETTING, METHODS: Immunohistochemical detection of K8/K18 was conducted in 40 archival ovarian samples from women aged 17-39 years. K8/K18 expression was analyzed at the different stages of follicle development and corpus luteum lifespan. The proportions of primordial follicles showing all K8/K18-positive, all K8/K18 negative, or a mixture of K8/K18 negative and positive granulosa cells were quantified in 18 ovaries, divided into three age groups: ≤ 25 years (N = 6), 26-30 (N = 6) and 31-36 (N = 6) years. A total number of 1793 primordial, 750 transitional and 140 primary follicles were scored. MAIN RESULTS AND THE ROLE OF CHANCE: A close association was found between changes in K8/K18 expression and cell death/cell survival events in the human granulosa cell lineage. Large secondary and early antral follicles (most of them undergoing atresia) and regressing corpora lutea displayed low/absent K8/K18 expression. Conversely, early growing and some large antral follicles, functional menstrual corpora lutea, as well as life-extended corpus luteum of pregnancy, in which cell death was scarce, showed high K8/K18 expression. Three sub-populations of primordial follicles were observed with respect to the presence of K8/K18 in their flattened granulosa cells, ranging from primordial follicles showing only positive granulosa cells [P0(+)], to others with a mixture of positive and negative cells [P0(+/-)] or follicles with only negative cells [P0(-)]. Significant age-related changes were found in the proportions of the different primordial follicle types. In relation to age, a positive correlation was found for P0(+) primordial follicles (R2= 0.7883, N = 18; P < 0.001), while negative correlations were found for P0(+/-) (R2 = 0.6853, N = 18; P < 0.001) and P0(-) (R2 = 0.6725, N = 18; P < 0.001) follicles. Furthermore, an age-related shift towards greater keratin expression was found in P0(+/-) follicles (χ2 = 19.07, P < 0.05). LARGE SCALE DATA: N/A. LIMITATIONS REASONS FOR CAUTION: This is a descriptive study. Hence, a cause-and-effect relationship between K8/K18 expression and cell death/survival cannot be directly established. WIDER IMPLICATIONS OF THE FINDINGS: This study describes, for the first time, the existence of sub-populations of primordial follicles on the basis of K8/K18 expression in granulosa cells, and that their proportions change with age. While a progressive increase in K8/K18 expression cannot be ruled out, our data are consistent with the hypothesis that primordial follicles expressing low levels of K8/K18 are preferentially ablated by follicle attrition, while primordial follicles showing high K8/K18 levels are those predominantly recruited into the growing pool. This suggests that K8/K18 expression could constitute a novel factor regulating primordial follicle death/survival, and raises the possibility that alterations of K8/K18 expression could be involved in the accelerated depletion of the ovarian reserve leading to premature ovarian insufficiency. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by Grants BFU2011-025021 and BFU2014-57581-P (Ministerio de Economía y Competitividad, Spain; co-funded with EU funds from FEDER Program); project PIE14-00005 (Flexi-Met, Instituto de Salud Carlos III, Ministerio de Sanidad, Spain); Projects P08-CVI-03788 and P12-FQM-01943 (Junta de Andalucía, Spain); and EU research contract DEER FP7-ENV-2007-1. CIBER Fisiopatología de la Obesidad y Nutrición is an initiative of Instituto de Salud Carlos III. The authors have nothing to disclose in relation to the contents of this study.


Assuntos
Morte Celular/fisiologia , Sobrevivência Celular/fisiologia , Células da Granulosa/metabolismo , Queratina-18/metabolismo , Queratina-8/metabolismo , Reserva Ovariana/fisiologia , Adolescente , Adulto , Linhagem da Célula/fisiologia , Corpo Lúteo/metabolismo , Feminino , Humanos , Queratina-18/genética , Queratina-8/genética , Adulto Jovem
9.
Front Neuroendocrinol ; 48: 37-49, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28754629

RESUMO

Albeit essential for perpetuation of species, reproduction is an energy-demanding function that can be adjusted to body metabolic status. Reproductive maturation and function can be suppressed in conditions of energy deficit, but can be altered also in situations of persistent energy excess, e.g., morbid obesity. This metabolic-reproductive integration, of considerable pathophysiological relevance to explain different forms of perturbed puberty and sub/infertility, is implemented by the concerted action of numerous central and peripheral regulators, which impinge at different levels of the hypothalamic-pituitary-gonadal (HPG) axis, permitting a tight fit between nutritional/energy status and gonadal function. We summarize here the major physiological mechanisms whereby nutritional and metabolic cues modulate the maturation and function of the HPG axis. We will focus on recent progress on the major central neuropeptide pathways, including kisspeptins, neurokinin B and the products of POMC and NPY neurons, which convey metabolic information to GnRH neurons, as major hierarchical hub of our reproductive brain.


Assuntos
Fertilidade/fisiologia , Neuropeptídeos/metabolismo , Neurotransmissores/metabolismo , Puberdade/metabolismo , Reprodução/fisiologia , Maturidade Sexual/fisiologia , Transdução de Sinais/fisiologia , Animais , Humanos
10.
Hum Reprod Update ; 23(6): 737-763, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28961976

RESUMO

BACKGROUND: Puberty is a complex developmental event, controlled by sophisticated regulatory networks that integrate peripheral and internal cues and impinge at the brain centers driving the reproductive axis. The tempo of puberty is genetically determined but is also sensitive to numerous modifiers, from metabolic and sex steroid signals to environmental factors. Recent epidemiological evidence suggests that the onset of puberty is advancing in humans, through as yet unknown mechanisms. In fact, while much knowledge has been gleaned recently on the mechanisms responsible for the control of mammalian puberty, fundamental questions regarding the intimate molecular and neuroendocrine pathways responsible for the precise timing of puberty and its deviations remain unsolved. OBJECTIVE AND RATIONALE: By combining data from suitable model species and humans, we aim to provide a comprehensive summary of our current understanding of the neuroendocrine mechanisms governing puberty, with particular focus on its central regulatory pathways, underlying molecular basis and mechanisms for metabolic control. SEARCH METHODS: A comprehensive MEDLINE search of articles published mostly from 2003 to 2017 has been carried out. Data from cellular and animal models (including our own results) as well as clinical studies focusing on the pathophysiology of puberty in mammals were considered and cross-referenced with terms related with central neuroendocrine mechanisms, metabolic control and epigenetic/miRNA regulation. OUTCOMES: Studies conducted during the last decade have revealed the essential role of novel central neuroendocrine pathways in the control of puberty, with a prominent role of kisspeptins in the precise regulation of the pubertal activation of GnRH neurosecretory activity. In addition, different transmitters, including neurokinin-B (NKB) and, possibly, melanocortins, have been shown to interplay with kisspeptins in tuning puberty onset. Alike, recent studies have documented the role of epigenetic mechanisms, involving mainly modulation of repressors that target kisspeptins and NKB pathways, as well as microRNAs and the related binding protein, Lin28B, in the central control of puberty. These novel pathways provide the molecular and neuroendocrine basis for the modulation of puberty by different endogenous and environmental cues, including nutritional and metabolic factors, such as leptin, ghrelin and insulin, which are known to play an important role in pubertal timing. WIDER IMPLICATIONS: Despite recent advancements, our understanding of the basis of mammalian puberty remains incomplete. Complete elucidation of the novel neuropeptidergic and molecular mechanisms summarized in this review will not only expand our knowledge of the intimate mechanisms responsible for puberty onset in humans, but might also provide new tools and targets for better prevention and management of pubertal deviations in the clinical setting.


Assuntos
Mamíferos/crescimento & desenvolvimento , Maturidade Sexual/fisiologia , Animais , Epigênese Genética , Humanos , Mamíferos/fisiologia , Sistemas Neurossecretores/fisiologia , Reprodução , Maturidade Sexual/genética , Transdução de Sinais
11.
Ars pharm ; 57(4): 177-181, oct.-dic. 2016. graf
Artigo em Espanhol | IBECS | ID: ibc-159646

RESUMO

Introducción: vancomicina es un antibiótico eficaz para el tratamiento de infecciones por gérmenes grampositivos, sin embargo la toxicidad renal asociada a su uso, ha relegado su utilización a líneas secundarias de uso. Este hecho ha consolidado el tratamiento empírico con antibióticos más caros. Objetivo: analizar los datos de monitorización de vancomicina y valorar la eficiencia frente al uso de otros antibióticos. Método: estudio observacional donde se analiza la monitorización farmacocinética de vancomicina y la eficiencia de una Unidad de Farmacocinética Clínica, con una población de 137 pacientes ingresados en un hospital general de especialidades. Resultados: la utilización de vancomicina en primera intención, supuso un ahorro de 16.472,82 € respecto al uso de daptomicina y de 83.039,83 € respecto al de linezolid. No obstante, el 18% de nuestra muestra no pudo ser tratado con vancomicina, lo que hace necesario disponer de otros fármacos


Introduction: vancomycin is an effective antibiotic for the treatment of infections due to Gram-positive germs, however renal toxicity associated with its use, has relegated its use to use secondary lines. This fact has consolidated the empirical treatment with more expensive antibiotics. Objective: to analyze the data of monitoring of vancomycin and rating the efficiency facing the use of other antibiotics. Materials and methods: observational study where discusses monitoring pharmacokinetics of Vancomycin and a unit of pharmacokinetics clinical efficiency, with a population of 137 patients admitted to a general hospital specialties. Results: the use of Vancomycin in first intention meant a savings of € 16.472,82 regarding the use of € 83.039,83 the linezolid and daptomycin. However, 18% of our sample not could be treated with Vancomycin, making it necessary to have other drugs


Assuntos
Humanos , Masculino , Feminino , Vancomicina/uso terapêutico , Monitoramento de Medicamentos/instrumentação , Monitoramento de Medicamentos/métodos , Monitoramento de Medicamentos , Daptomicina/uso terapêutico , Linezolida/uso terapêutico , Monitoramento de Medicamentos/tendências , Estudos Prospectivos , Vancomicina/farmacocinética , Daptomicina/farmacocinética , Linezolida/farmacocinética
12.
Ars pharm ; 57(2): 49-54, abr.-jun. 2016. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-156807

RESUMO

Introducción: la Prescripción Electrónica Asistida (PEA), constituye en la actualidad una herramienta útil en el proceso de hospitalización. La supresión de la prescripción y/o transcripción manuscrita, ha conseguido minimizar los errores relacionados con la medicación, mitigando la constante preocupación que supone la seguridad del paciente. Objetivo: analizar los datos de intervención farmacéutica registrados tras la implantación de un software de prescripción electrónica y la seguridad que confiere al usuario. Material y método: estudio retrospectivo de cinco meses de duración, en el que se revisaron las historias clínicas electrónicas de prescripción, describiendo los errores de medicación detectados y el número de intervenciones farmacéuticas realizadas. Resultados: sobre un total de 27.533 validaciones, fueron realizadas 4.917 intervenciones farmacéuticas (IF), lo que supone 32,78 errores de medicación/día y 0,95 errores/paciente


Introduction: the Electronically Assisted Prescription (EAP) is now a useful tool in the process of hospitalization. The removal of the prescription or transcript handwritten, has managed to minimize errors related to medication, mitigating the constant concern involving the safety of the patient. Objective: to analyze data pharmaceutical intervention reported following implementation of a software for e-prescribing and the security that gives the user. Materials and methods: retrospective study of five months duration, which reviewed the electronic medical records of prescription, describing medication errors that are detected and the number of pharmaceutical interventions carried out. Results: out of a total of 27.533 validations, were performed 4.917 pharmaceutical interventions (IF), which represents 32.78 medication errors per day and 0.95 errors per patient


Assuntos
Humanos , Masculino , Feminino , Medicamentos sob Prescrição/uso terapêutico , Prescrição Eletrônica/classificação , Prescrição Eletrônica/normas , Erros de Medicação/legislação & jurisprudência , Erros de Medicação/estatística & dados numéricos , Erros de Medicação/tendências , Segurança do Paciente , Estudos Retrospectivos , Governança Clínica/normas , Governança Clínica/tendências
13.
Sci Rep ; 5: 15683, 2015 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-26494358

RESUMO

The Lin28/let-7 system, which includes the RNA-binding proteins, Lin28a/Lin28b, and let-7 miRNAs, has emerged as putative regulator of puberty and male gametogenesis; yet, its expression pattern and regulation in postnatal testis remain ill defined. We report herein expression profiles of Lin28 and let-7 members, and related mir-145 and mir-132, in rat testis during postnatal maturation and in models of altered puberty and hormonal deregulation. Neonatal expression of Lin28a and Lin28b was low and rose markedly during the infantile period; yet, expression patterns diverged thereafter, with persistently elevated levels only for Lin28b, which peaked at puberty. Let-7a, let-7b, mir-132 and mir-145 showed profiles opposite to Lin28b. In fact, let-7b and mir-145 were abundant in pachytene spermatocytes, but absent in elongating spermatids, where high expression of Lin28b was previously reported. Perturbation of puberty by neonatal estrogenization reverted the Lin28/let-7 expression ratio; expression changes were also detected in other models of delayed puberty, due to early photoperiod or nutritional manipulations. In addition, hypophysectomy or growth hormone (GH) deficiency revealed regulation of this system by gonadotropins and GH. Our data document the expression profiles of the Lin28/let-7 system in rat testis along postnatal/pubertal maturation, and their perturbation in models of pubertal and hormonal manipulation.


Assuntos
MicroRNAs/genética , Proteínas de Ligação a RNA/genética , Maturidade Sexual , Testículo/metabolismo , Animais , Humanos , Masculino , Ratos , Ratos Endogâmicos Lew , Ratos Wistar
14.
Ars pharm ; 56(3): 161-164, jul.-sept. 2015. tab
Artigo em Espanhol | IBECS | ID: ibc-144110

RESUMO

Introducción. La inadecuada utilización de los antibióticos restringidos (ATBr) en el entorno hospitalario, constituyen en la actualidad un importante problema de salud. Su uso indiscriminado y la ausencia de supervisión por parte de especialistas en enfermedades infecciosas, están contribuyendo a una acelerada selección de cepas resistentes, lo que se traduce en un cada vez más reducido arsenal terapéutico. Objetivo. Analizar la correcta o incorrecta indicación de los antibióticos restringidos en nuestro hospital, de acuerdo al diagnóstico principal. Material y método. Estudio observacional y descriptivo de una serie de 126 casos consecutivos analizados a lo largo de seis meses, en el que se revisaron tanto historias clínicas como solicitudes de antibióticos restringidos. Resultados. El 61,11% de los pacientes a los que se les prescribió un ATBr habían recibido tratamiento previo y en un 19,84% los ATBr fueron prescritos de inicio. El 73% de las prescripciones eran inadecuadas o estaban incompletas


Introduction. The improper use of restricted antibiotics (ATBr) in the hospital environment, currently constitute a major health problem. Their indiscriminate use and the absence of oversight by specialists in infectious diseases, are contributing to an accelerated selection of resistant strains, which translates into an increasingly smaller therapeutic arsenal. Objective. To analyze the right or wrong indication of restricted antibiotics in our hospital, according to the primary diagnosis. Material and methods. Observational and descriptive study of a series of 126 consecutive cases analyzed over six months, in which we reviewed both stories clinics as requests for restricted antibiotics. Results. The 61.11% of patients who are prescribed an ATBr had been treated prior and a 19.84% the ATBr were prescribed home. The 73% remaining prescriptions were inadequate or incomplete


Assuntos
Antibacterianos/uso terapêutico , Prescrições de Medicamentos , Uso Indevido de Medicamentos sob Prescrição , Infecção Hospitalar/tratamento farmacológico , Fidelidade a Diretrizes , Monitoramento Epidemiológico/tendências , Controle de Medicamentos e Entorpecentes , Resistência Microbiana a Medicamentos , Estudos Retrospectivos , Espanha/epidemiologia
15.
Ars pharm ; 56(2): 115-120, abr.-jun. 2015. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-139448

RESUMO

Introducción. Cada vez son más los hospitales que incorporan en su tecnología software informáticos capaces de elaborar una nutrición eficaz, segura y ajustada a las necesidades de los pacientes con el fin de minimizar errores. Sin embargo, estos programas no siempre disponen de un manejo intuitivo, lo que en ocasiones, pueden comportar diversas dificultades que los haga estar infrautilizados y en consecuencia, el número de prescripciones puede verse disminuido. Objetivo: Evaluar la reducción en la prescripción de nutriciones parenterales y el impacto económico que ha supuesto en nuestro centro, tras la implantación de un software informático de prescripción electrónica para nutriciones parenterales. Material y métodos. Se utilizó un software informático de Fresenius-Kabi España (v. 1.8/2011) como base de datos, para clasificar las NP prescritas durante los últimos 24 meses, teniendo en cuenta la implantación de la herramienta informática. Este procedimiento se usó para determinar la disminución en la prescripción de nutriciones. Resultados. Durante el año 2013 se prescribieron un total de 3.530 nutriciones parenterales, mientras que en el mismo periodo de 2014, las nutriciones prescritas fueron 2.622. Esta diferencia de 908 prescripciones, supuso un ahorro económico de 22.230,03 Euros


Introduction. Increasingly hospitals that incorporate in its software technology computer capable of developing a nutrition effective, safe and adjusted to the needs of patients in order to minimize errors. However, these programs do not always have an intuitive, sometimes, may lead to difficulties making them to be underused and as a result, the number of prescriptions will be decreased. Objective. To evaluate the reduction in prescription of parenteral nutritions and the economic impact that has been in our centre, the introduction of computer software for electronic prescription for parenteral nutritions. Material and method. A computer software of Fresenius-Kabi Spain (v. 1.8/2011) as the database, was used to classify the NP prescribed during the past 24 months, taking into account the implementation of the computer tool. This procedure was used to determine the reduction in prescription of nutritions. Results. During the year 2013 were prescribed a total of 3.530 parenteral nutritions, while in the same period in 2014, prescribed nutritions were 2.622. This difference of 908 prescriptions meant a savings of 22.230,03 Euros


Assuntos
Feminino , Humanos , Masculino , Prescrição Eletrônica/economia , Prescrição Eletrônica/história , Informática em Saúde Pública/legislação & jurisprudência , Informática em Saúde Pública/métodos , Nutrição Parenteral/métodos , Nutrição Parenteral/psicologia , Epidemiologia Descritiva , Prescrição Eletrônica/enfermagem , Prescrição Eletrônica/normas , Informática em Saúde Pública/economia , Informática em Saúde Pública , Nutrição Parenteral/instrumentação , Nutrição Parenteral/enfermagem , Estudos Retrospectivos
16.
Endocrinology ; 156(2): 576-88, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25490143

RESUMO

Kisspeptin/neurokinin B/dynorphin (KNDy) neurons, which coexpress kisspeptins (Kps), neurokinin B (NKB), and dynorphin (Dyn), regulate gonadotropin secretion. The KNDy model proposes that NKB (a stimulator, through NK3R) and Dyn (an inhibitor, through κ-opioid receptor) shape Kp secretion onto GnRH neurons. However, some aspects of this paradigm remain ill defined. Here we aimed to characterize the following: 1) the effects of NKB signaling on FSH secretion and 2) the role of Dyn in gonadotropin secretion after NK3R activation; 3) additionally, we explored the roles of other tachykinin receptors, NK1R and NK2R, on gonadotropin release. Thus, the effects of the NK3R agonist, senktide, on FSH release were explored across postnatal development in male and female rats; gonadotropin responses to agonists of NK1R substance P and NK2R [neurokinin A (NKA)] were also monitored. Moreover, the effects of senktide on gonadotropin secretion were assessed after antagonizing Dyn actions by nor-binaltorphimine didydrochloride. Before puberty, rats of both sexes showed increased FSH secretion to senktide (and Kp-10). Conversely, adult female rats were irresponsive to senktide in terms of FSH, despite proven LH responses, whereas the adult males did not display FSH or LH responses to senktide, even at high doses. In turn, substance P and NKA stimulated gonadotropin secretion in prepubertal rats, whereas in adults modest gonadotropin responses to NKA were detected. By pretreatment with a Dyn antagonist, adult males became responsive to senktide in terms of LH secretion and displayed elevated basal LH and FSH levels; nor-binaltorphimine didydrochloride treatment uncovered FSH responses to senktide in adult females. Furthermore, the expression of Pdyn and Opkr1 (encoding Dyn and κ-opioid receptor, respectively) in the mediobasal hypothalamus was greater in males than in females at prepubertal ages. Overall, our data contribute to refining our understanding on how the elements of the KNDy node and related factors (ie, other tachykinins) differentially participate in the control of gonadotropins at different stages of rat postnatal maturation.


Assuntos
Envelhecimento/metabolismo , Hormônio Foliculoestimulante/metabolismo , Kisspeptinas/metabolismo , Hormônio Luteinizante/metabolismo , Neurocinina B/metabolismo , Animais , Dinorfinas/antagonistas & inibidores , Dinorfinas/metabolismo , Encefalinas/metabolismo , Feminino , Hipotálamo/metabolismo , Masculino , Neurocinina B/agonistas , Fragmentos de Peptídeos , Precursores de Proteínas/metabolismo , Ratos Wistar , Receptores da Neurocinina-1/agonistas , Receptores da Neurocinina-2/agonistas , Substância P/análogos & derivados
17.
Hum Reprod ; 29(12): 2736-46, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25316443

RESUMO

STUDY QUESTION: Are neurokinin B (NKB), NK3 receptor (NK3R), kisspeptin (KISS1) and kisspeptin receptor (KISS1R) expressed in human ovarian granulosa cells? SUMMARY ANSWER: The NKB/NK3R and kisspeptin/KISS1R systems are co-expressed and functionally active in ovarian granulosa cells. WHAT IS KNOWN ALREADY: The NKB/NK3R and KISS1/KISS1R systems are essential for reproduction. In addition to their well-recognized role in hypothalamic neurons, these peptide systems may contribute to the control of fertility by acting directly on the gonads, but such a direct gonadal role remains largely unknown. STUDY DESIGN, SIZE, DURATION: This study analyzed matched mural granulosa cells (MGCs) and cumulus cells (CCs) collected from preovulatory follicles of oocyte donors at the time of oocyte retrieval. PARTICIPANTS/MATERIALS, SETTING, METHODS: The samples were provided by 56 oocyte donor women undergoing ovarian stimulation treatment. Follicular fluid samples containing MGCs and cumulus-oocyte complexes were collected after transvaginal ultrasound-guided oocyte retrieval. RT-PCR, quantitative real-time PCR, immunocytochemistry and western blot were used to investigate the pattern of expression of the NKB/NK3R and KISS/KISS1R systems in MGCs and CCs. Intracellular free Ca(2+) levels, [Ca(2+)]i, in MGCs after exposure to NKB or KISS1, in the presence or not of tachykinin receptor antagonists, were also measured. MAIN OUTCOME AND THE ROLE OF CHANCE: NKB/NK3R and KISS1/KISS1R systems were expressed, at the mRNA and protein levels, in MGCs and CCs, with significantly higher expression in CCs. Kisspeptin increased the [Ca(2+)]i in the cytosol of human MGCs while exposure to NKB failed to induce any change in [Ca(2+)]i. However, the [Ca(2+)]i response to kisspeptin was reduced in the presence of NKB. The inhibitory effect of NKB was only partially mimicked by the NK3R agonist, senktide and marginally suppressed by the NK3R-selective antagonist SB 222200. Yet, a cocktail of antagonists selective for the NK1, NK2 and NK3 receptors blocked the effect of NKB. LIMITATIONS, REASONS FOR CAUTION: The granulosa and cumulus cells were obtained from oocyte donors undergoing ovarian stimulation, which in comparison with natural cycles, may have affected gene and protein expression in granulosa cells. WIDER IMPLICATIONS OF THE FINDINGS: Our data demonstrate that, in addition to their indispensable effects at the central nervous system, the NKB/NK3R and kisspeptin/KISS1R systems are co-expressed and are functionally active in non-neuronal reproductive cells of the female gonads, the ovarian granulosa cells. STUDY FUNDING/ COMPETING INTERESTS: This work was supported by grants from Ministerio de Economía y Competitividad (CTQ2011-25564 and BFI2011-25021) and Junta de Andalucía (P08-CVI-04185), Spain. J.G.-O., F.M.P., M.F.-S., N.P., A.C.-R., T.A.A., M.H., M.R., M.T.-S. and L.C. have nothing to declare.


Assuntos
Células da Granulosa/metabolismo , Kisspeptinas/metabolismo , Neurocinina B/metabolismo , Receptores de Taquicininas/metabolismo , Células Cultivadas , Feminino , Humanos , Kisspeptinas/genética , Neurocinina B/genética , RNA Mensageiro/metabolismo , Receptores de Taquicininas/genética
18.
Curr Mol Med ; 14(1): 3-21, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24236459

RESUMO

Optimal cellular function and therefore organism's survival is determined by the sensitive and accurate convergence of energy and nutrient abundance to cell growth and division. Among other factors, this integration is coupled by the target of rapamycin (TOR) pathway, which is able to sense nutrient, energy and oxygen availability and also growth factor signaling. Indeed, TOR signaling regulates cell energy homeostasis by coordinating anabolic and catabolic processes for survival. TOR, named mTOR in mammals, is a conserved serine/threonine kinase that exists in two different complexes, mTORC1 and mTORC2. Recently, studies are suggesting that alterations of those complexes promote disease and disrupted phenotypes, such as aging, obesity and related disorders and even cancer. The evidences linking mTOR to energy and metabolic homeostasis included the following. At central level mTOR regulates food intake and body weight being involved in the mechanism by which signals such as leptin and ghrelin exert its effects. At peripheral level it influences adipogenesis and lipogenesis in different tissues including the liver. Noteworthy chronic nutritional activation of mTOR signaling has been implicated in the development of beta cell mass expansion and on insulin resistance. Understanding of mTOR and other molecular switches, such as AMP-activated protein kinase (AMPK), as well as their interrelationship is crucial to know how organisms maintain optimal homeostasis. This review summarizes the role of hypothalamic TOR complex in cellular energy sensing, evidenced in the last years, focusing on the metabolic pathways where it is involved and the importance of this metabolic sensor in cellular and whole body energy management. Understanding the exact role of hypothalamic mTOR may provide new cues for therapeutic intervention in diseases.


Assuntos
Hipotálamo/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Metabolismo Energético , Hormônios/metabolismo , Hormônios/farmacologia , Humanos , Hipotálamo/efeitos dos fármacos , Alvo Mecanístico do Complexo 1 de Rapamicina , Alvo Mecanístico do Complexo 2 de Rapamicina , Modelos Biológicos , Complexos Multiproteicos/metabolismo , Puberdade/genética , Puberdade/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/genética
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