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INTRODUCTION: Laparoscopic sacrocolpopexy (LSCP) is currently the gold standard surgical technique for treating pelvic prolapse. This study aimed to evaluate the feasibility of laparoscopic sacrocolpopexy in ambulatory care. PATIENTS AND METHODS: This prospective study was conducted to evaluate the feasibility of LSCP in women who visited the outpatient department of obstetrics and gynecology at the University Hospital of Strasbourg between July 2018 and December 2021. All women with indications for laparoscopic sacrocolpopexy for prolapse treatment who were willing to be treated as outpatients were included. The main criterion of the study was to evaluate the rate of re-hospitalization between discharge from the outpatient department after LSCP and postoperative follow-up consultations. RESULTS: Among the whole population (57/200, 28.5 %) included, 4 (7 %) were hospitalized. The quality of life was not altered with a preserved EuroQol (EQ-5D) quality of life score with a mean score of 73±18.4 standard deviation (SD) 95 % confidence interval (CI) (67.9; 78.1) on postoperative day 3 (D3) and 91.2 ± 16.3 SD 95 % CI (86.2-96) on D30. On D1, D2, D3, and D7, the anxiety rate evaluated by State-Trait Anxiety Inventory score (STAI Y-A) remained low, with mean scores of 24.8 ± 9.6 SD 95 % [23.4-26.5] on D30. All patients were satisfied or very satisfied with the procedure and outpatient management, with an average score of 9.6/10 (range: 8-10). CONCLUSION: This prospective, monocentric study evaluating the feasibility of outpatient LSCP reported demonstrated low rates of complications and re-hospitalization after outpatient management. Furthermore, the patients' quality of life was not altered, and they patients were satisfied with this type of management.
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Procedimientos Quirúrgicos Ambulatorios , Estudios de Factibilidad , Laparoscopía , Prolapso de Órgano Pélvico , Calidad de Vida , Humanos , Femenino , Laparoscopía/métodos , Persona de Mediana Edad , Estudios Prospectivos , Prolapso de Órgano Pélvico/cirugía , Anciano , Procedimientos Quirúrgicos Ambulatorios/métodos , Procedimientos Quirúrgicos Ginecológicos/métodos , Readmisión del Paciente/estadística & datos numéricosRESUMEN
Ammonia oxidation is the rate-limiting first step of nitrification and a key process in the nitrogen cycle that results in the formation of nitrite (NO2 -), which can be further oxidized to nitrate (NO3 -). In the Amazonian floodplains, soils are subjected to extended seasons of flooding during the rainy season, in which they can become anoxic and produce a significant amount of methane (CH4). Various microorganisms in this anoxic environment can couple the reduction of different ions, such as NO2 - and NO3 -, with the oxidation of CH4 for energy production and effectively link the carbon and nitrogen cycle. Here, we addressed the composition of ammonium (NH4 +) and NO3 --and NO2 --dependent CH4-oxidizing microbial communities in an Amazonian floodplain. In addition, we analyzed the influence of environmental and geochemical factors on these microbial communities. Soil samples were collected from different layers of forest and agroforest land-use systems during the flood and non-flood seasons in the floodplain of the Tocantins River, and next-generation sequencing of archaeal and bacterial 16S rRNA amplicons was performed, coupled with chemical characterization of the soils. We found that ammonia-oxidizing archaea (AOA) were more abundant than ammonia-oxidizing bacteria (AOB) during both flood and non-flood seasons. Nitrogen-dependent anaerobic methane oxidizers (N-DAMO) from both the archaeal and bacterial domains were also found in both seasons, with higher abundance in the flood season. The different seasons, land uses, and depths analyzed had a significant influence on the soil chemical factors and also affected the abundance and composition of AOA, AOB, and N-DAMO. During the flood season, there was a significant correlation between ammonia oxidizers and N-DAMO, indicating the possible role of these oxidizers in providing oxidized nitrogen species for methanotrophy under anaerobic conditions, which is essential for nitrogen removal in these soils.
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BACKGROUND: Recent research has suggested that excessive alcohol consumption in patients with alcohol use disorder (AUD) is associated with chronic immune activation, which affects the metabolism of the neurotransmitter precursor amino acid tryptophan (TRP) and contributes to the complex pathophysiology of AUD. Our study investigated possible immune-associated alterations of TRP to kynurenine (KYN) metabolism in patients with AUD during acute alcohol withdrawal. METHODS: We measured serum concentrations of TRP, KYN, quinolinic (QUIN), kynurenic acid (KYNA), and the immune activation marker neopterin (NEO) at the first, fifth and 10th day of alcohol withdrawal in patients with AUD, who attended a standardized in-patient treatment program and underwent a detailed clinical assessment. RESULTS: Data from these individuals were compared to data from a reference control group (RCG). The primary outcome measures were the differences in serum concentrations of metabolites between AUD patients and RCG and correlations between NEO and metabolites of the tryptophan-kynurenine pathway. r = 0.695, p < 0.001) in the AUD group. Mixed models analysis showed that NEO concentrations were positively associated with QUIN but not with KYNA concentrations. Several behavioral symptoms correlated positively with QUIN concentrations and negatively with the KYNA/QUIN ratio. CONCLUSIONS: Our findings demonstrate that the changes in TRP catabolism in acute alcohol withdrawal resulting in increased KYN production could reflect the involvement of immune-associated activation of the enzyme indoleamine 2,3-dioxygenase, as NEO concentrations correlated with the KYN/TRP ratio. In addition, our data show that this low-grade immune activation may cause an imbalance in the production of neurotoxic and neuroprotective kynurenine metabolites in AUD.
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Alcoholismo , Síndrome de Abstinencia a Sustancias , Consumo de Bebidas Alcohólicas , Biomarcadores/metabolismo , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Ácido Quinurénico , Quinurenina/metabolismo , Neopterin , Ácido Quinolínico/metabolismo , Triptófano/metabolismoRESUMEN
We study the large-amplitude response of classical molecules to electromagnetic radiation, showing the universality of the transition from linear to nonlinear response and breakup at sufficiently large amplitudes. We demonstrate that a range of models, from the simple harmonic oscillator to the successful Peyrard-Bishop-Dauxois type models of DNA, which include realistic effects of the environment (including damping and dephasing due to thermal fluctuations), lead to characteristic universal behavior: formation of domains of dissociation in driving force amplitude-frequency space, characterized by the presence of local boundary minima. We demonstrate that by simply following the progression of the resonance maxima in this space, while gradually increasing intensity of the radiation, one must necessarily arrive at one of these minima, i.e., a point where the ultrahigh spectral selectivity is retained. We show that this universal property, applicable to other oscillatory systems, is a consequence of the fact that these models belong to the fold catastrophe universality class of Thom's catastrophe theory. This in turn implies that for most biostructures, including DNA, high spectral sensitivity near the onset of the denaturation processes can be expected. Such spectrally selective molecular denaturation could find important applications in biology and medicine.
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BACKGROUND: Women with a history of gestational diabetes mellitus (GDM) have a 7-fold higher risk of developing type 2 diabetes (T2D) during midlife and an elevated risk of developing hypertension and cardiovascular disease. Glucose tolerance reclassification after delivery is recommended, but fewer than 40% of women with GDM are tested. Thus, improved risk stratification methods are needed, as is a deeper understanding of the pathology underlying the transition from GDM to T2D. We hypothesize that metabolites during the early postpartum period accurately distinguish risk of progression from GDM to T2D and that metabolite changes signify underlying pathophysiology for future disease development. METHODS AND FINDINGS: The study utilized fasting plasma samples collected from a well-characterized prospective research study of 1,035 women diagnosed with GDM. The cohort included racially/ethnically diverse pregnant women (aged 20-45 years-33% primiparous, 37% biparous, 30% multiparous) who delivered at Kaiser Permanente Northern California hospitals from 2008 to 2011. Participants attended in-person research visits including 2-hour 75-g oral glucose tolerance tests (OGTTs) at study baseline (6-9 weeks postpartum) and annually thereafter for 2 years, and we retrieved diabetes diagnoses from electronic medical records for 8 years. In a nested case-control study design, we collected fasting plasma samples among women without diabetes at baseline (n = 1,010) to measure metabolites among those who later progressed to incident T2D or did not develop T2D (non-T2D). We studied 173 incident T2D cases and 485 controls (pair-matched on BMI, age, and race/ethnicity) to discover metabolites associated with new onset of T2D. Up to 2 years post-baseline, we analyzed samples from 98 T2D cases with 239 controls to reveal T2D-associated metabolic changes. The longitudinal analysis tracked metabolic changes within individuals from baseline to 2 years of follow-up as the trajectory of T2D progression. By building prediction models, we discovered a distinct metabolic signature in the early postpartum period that predicted future T2D with a median discriminating power area under the receiver operating characteristic curve of 0.883 (95% CI 0.820-0.945, p < 0.001). At baseline, the most striking finding was an overall increase in amino acids (AAs) as well as diacyl-glycerophospholipids and a decrease in sphingolipids and acyl-alkyl-glycerophospholipids among women with incident T2D. Pathway analysis revealed up-regulated AA metabolism, arginine/proline metabolism, and branched-chain AA (BCAA) metabolism at baseline. At follow-up after the onset of T2D, up-regulation of AAs and down-regulation of sphingolipids and acyl-alkyl-glycerophospholipids were sustained or strengthened. Notably, longitudinal analyses revealed only 10 metabolites associated with progression to T2D, implicating AA and phospholipid metabolism. A study limitation is that all of the analyses were performed with the same cohort. It would be ideal to validate our findings in an independent longitudinal cohort of women with GDM who had glucose tolerance tested during the early postpartum period. CONCLUSIONS: In this study, we discovered a metabolic signature predicting the transition from GDM to T2D in the early postpartum period that was superior to clinical parameters (fasting plasma glucose, 2-hour plasma glucose). The findings suggest that metabolic dysregulation, particularly AA dysmetabolism, is present years prior to diabetes onset, and is revealed during the early postpartum period, preceding progression to T2D, among women with GDM. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01967030.
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Aminoácidos/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Gestacional/metabolismo , Metabolismo de los Lípidos , Adulto , Progresión de la Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Periodo Posparto/metabolismo , Embarazo , Factores de Riesgo , Adulto JovenRESUMEN
Non-alcoholic fatty liver disease (NAFLD) is a chronic disease in which excessive amount of lipids is accumulated as droplets in hepatocytes. Recently, cumulative evidences suggested that a sustained de novo lipogenesis can play an important role in NAFLD. Dysregulated expression of lipogenic genes, including ATP-citrate lyase (ACLY), has been found in liver diseases associated with lipid accumulation. ACLY is a ubiquitous cytosolic enzyme positioned at the intersection of nutrients catabolism and cholesterol and fatty acid biosyntheses. In the present study, the molecular mechanism of ACLY expression in a cell model of steatosis has been reported. We identified an internal ribosome entry site (IRES) in the 5' untranslated region of the ACLY mRNA, that can support an efficient mRNA translation through a Cap-independent mechanism. In steatotic HepG2 cells, ACLY expression was up-regulated through IRES-mediated translation. Since it has been demonstrated that lipid accumulation in cells induces endoplasmic reticulum (ER) stress, the involvement of this cellular pathway in the translational regulation of ACLY has been also evaluated. Our results showed that ACLY expression was increased in ER-stressed cells, through IRES-mediated translation of ACLY mRNA. A potential role of the Cap-independent translation of ACLY in NAFLD has been discussed.
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ATP Citrato (pro-S)-Liasa/genética , Hepatocitos/metabolismo , Lipogénesis , Biosíntesis de Proteínas , ARN Mensajero/genética , Regiones no Traducidas 5' , ATP Citrato (pro-S)-Liasa/metabolismo , Estrés del Retículo Endoplásmico , Células Hep G2 , Humanos , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , ARN Mensajero/metabolismoRESUMEN
The coupling between ferrous iron and methane production has important global implications, with iron ions acting as electron acceptors for anaerobic oxidation of methane (AOM) and inhibitors of methanogenesis in different environments, including floodplain soils. In this sense, we analyzed the relationship between Fe(II) concentration and methane production in soil layers collected at 0-15 cm and 15-30 cm from flooded-forest and -agroforestry in Amazonian clear water floodplain incubated in anaerobic batch reactors using acetate, formate and glucose as organic sources. High throughput sequencing of archaeal and bacterial 16S rRNA genes was employed to assess the abundance and composition of the active methanogenic and methanotrophic microbial groups potentially involved in Fe(III)-dependent AOM in the soil used as inoculum. Positive correlation was revealed between Fe(II) concentration and methane production, with higher accumulation of Fe(II) in incubated soil layer collected at 0-15 cm in both forest and agroforestry sites for all the three organic sources. The accumulation of Fe(II) in the incubated soil evidenced the oxidation of Fe(III) potentially by Methanobacterium, Desulfobulbus and 'Candidatus methanoperedens nitroreducens' living in anaerobic condition at this soil layer. The results point out to the microbial ferric iron reduction as an important potential pathway for anaerobic organic matter decomposition in Amazonian floodplain, evidencing methanogenesis suppression by Fe(III) reduction in flooded-forest and -agroforestry in Amazonian clear water river floodplain.
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Contaminantes Atmosféricos/metabolismo , Inundaciones , Metano/metabolismo , Microbiología del Suelo , Anaerobiosis , Archaea/metabolismo , Brasil , Compuestos Férricos/metabolismo , Bosques , Agua Dulce , Hierro/metabolismo , Methanosarcinales/metabolismo , Oxidación-Reducción , ARN Ribosómico 16S/genética , SueloRESUMEN
l-Carnitine is an amino acid derivative widely known for its involvement in the transport of long-chain fatty acids into the mitochondrial matrix, where fatty acid oxidation occurs. Moreover, l-Carnitine protects the cell from acyl-CoA accretion through the generation of acylcarnitines. Circulating carnitine is mainly supplied by animal-based food products and to a lesser extent by endogenous biosynthesis in the liver and kidney. Human muscle contains high amounts of carnitine but it depends on the uptake of this compound from the bloodstream, due to muscle inability to synthesize carnitine. Mitochondrial fatty acid oxidation represents an important energy source for muscle metabolism particularly during physical exercise. However, especially during high-intensity exercise, this process seems to be limited by the mitochondrial availability of free l-carnitine. Hence, fatty acid oxidation rapidly declines, increasing exercise intensity from moderate to high. Considering the important role of fatty acids in muscle bioenergetics, and the limiting effect of free carnitine in fatty acid oxidation during endurance exercise, l-carnitine supplementation has been hypothesized to improve exercise performance. So far, the question of the role of l-carnitine supplementation on muscle performance has not definitively been clarified. Differences in exercise intensity, training or conditioning of the subjects, amount of l-carnitine administered, route and timing of administration relative to the exercise led to different experimental results. In this review, we will describe the role of l-carnitine in muscle energetics and the main causes that led to conflicting data on the use of l-carnitine as a supplement.
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Carnitina/análogos & derivados , Carnitina/metabolismo , Metabolismo Energético/efectos de los fármacos , Ácidos Grasos/metabolismo , Mitocondrias/metabolismo , Músculo Esquelético/metabolismo , Carnitina/administración & dosificación , Carnitina/biosíntesis , Carnitina/química , Carnitina/farmacología , Carnitina O-Palmitoiltransferasa/metabolismo , Suplementos Dietéticos/efectos adversos , Ejercicio Físico/fisiología , Humanos , Metilaminas/metabolismo , Músculo Esquelético/efectos de los fármacos , Oxidación-ReducciónRESUMEN
Obesity, type 2 diabetes, and other metabolic disorders have a large impact on global health, especially in Western countries. An important hallmark of metabolic disorders is chronic low-grade inflammation. A key player in chronic low-grade inflammation is dysmetabolism, which is defined as the inability to keep homeostasis resulting in loss of lipid control, oxidative stress, inflammation, and insulin resistance. Although often not yet detectable in the circulation, chronic low-grade inflammation can be present in one or multiple organs. The response to a metabolic challenge containing lipids may magnify dysfunctionalities at the tissue level, causing an overflow of inflammatory markers into the circulation and hence allow detection of early low-grade inflammation. Here, we summarize the evidence of successful application of metabolic challenge tests in type 2 diabetes, metabolic syndrome, obesity, and unhealthy aging. We also review how metabolic challenge tests have been successfully applied to evaluate nutritional intervention effects, including an "anti-inflammatory" mixture, dark chocolate, whole grain wheat and overfeeding. Additionally, we elaborate on future strategies to (re)gain inflammatory flexibility. Through epigenetic and metabolic regulation, the inflammatory response may be trained by regular mild and metabolic triggers, which can be understood from the perspective of trained immunity, hormesis and pro-resolution. New strategies to optimize dynamics of inflammation may become available.
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Quercetin (Que), a widely distributed flavonoid in the human diet, exerts neuroprotective action because of its property to antagonize oxidative stress. Here, we investigated the effects of Que on lipid synthesis in C6 glioma cells. A rapid Que-induced inhibition of cholesterol and, to a lesser extent, of fatty acid synthesis from [1-14C]acetate was observed. The maximum decrease was detected at the level of palmitate, the end product of de novo fatty acid synthesis. The effect of Que on the enzyme activities of acetyl-CoA carboxylase 1 (ACC1) and fatty acid synthase (FAS), the two enzymes of this pathway, was investigated directly in situ in permeabilized C6 cells. An inhibitory effect on ACC1 was observed after 4â¯h of 25⯵M Que treatment, while FAS activity was not affected. A reduction of polar lipid biosynthesis was also detected. A remarkable decrease of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) activity, regulatory enzyme of cholesterol synthesis, was evidenced. Expression studies demonstrated that Que acts at transcriptional level, by reducing the mRNA abundance and protein amount of ACC1 and HMGCR. Deepening the molecular mechanism, we found that Que decreased the expression of SREBP-1 and SREBP-2, transcriptional factors representing the main regulators of de novo fatty acid and cholesterol synthesis, respectively. Que also reduced the nuclear content of ChREBP, a glucose-induced transcription factor involved in the regulation of lipogenic genes. Our results represent the first evidence that a direct and rapid downregulatory effect of Que on cholesterol and de novo fatty acid synthesis is elicited in C6 cells.
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Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Colesterol/metabolismo , Ácidos Grasos/metabolismo , Glioma/metabolismo , Quercetina/antagonistas & inhibidores , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Animales , Humanos , RatasRESUMEN
Methyl cytosine binding protein 2 (MeCP2) is a structural chromosomal protein involved in the regulation of gene expression. Mutations in the gene encoding MeCP2 result in Rett Syndrome (RTT), a pervasive neurodevelopmental disorder. RTT is one of few autism spectrum disorders whose cause was identified as a single gene mutation. Remarkably, abnormal levels of MeCP2 have been associated to other neurodevelopmental disorders, as well as neuropsychiatric disorders. Therefore, many studies have been oriented to investigate the role of MeCP2 in the nervous system. In the present work, we explore cellular and molecular mechanisms affecting synaptic plasticity events in vivo in the hippocampus of MeCP2 mutant mice. While most studies addressed postsynaptic defects in the absence of MeCP2, we took advantage of an in vivo activity-paradigm (seizures), two models of MeCP2 deficiency, and neurobiological assays to reveal novel defects in presynaptic structural plasticity in the hippocampus in RTT rodent models. These approaches allowed us to determine that MeCP2 mutations alter presynaptic components, i.e., disrupts the plastic response of mossy fibers to synaptic activity and results in reduced axonal growth which is correlated with imbalanced trophic and guidance support, associated with aberrant expression of brain-derived neurotrophic factor and semaphorin 3F. Our results also revealed that adult-born granule cells recapitulate maturational defects that have been only shown at early postnatal ages. As these cells do not mature timely, they may not integrate properly into the adult hippocampal circuitry. Finally, we performed a hippocampal-dependent test that revealed defective spatial memory in these mice. Altogether, our studies establish a model that allows us to evaluate the effect of the manipulation of specific pathways involved in axonal guidance, synaptogenesis, or maturation in specific circuits and correlate it with changes in behavior. Understanding the mechanisms underlying the neuronal compromise caused by mutations in MeCP2 could provide information on the pathogenic mechanism of autistic spectrum disorders and improve our understanding of brain development and molecular basis of behavior.
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Although insulin resistance (IR) is a key pathophysiologic condition underlying various metabolic disorders, impaired cellular glucose uptake is one of many manifestations of metabolic derangements in the human body. To study the systems-wide molecular changes associated with obesity-dependent IR, we integrated information on plasma proteins and microRNAs in eight obese insulin-resistant (OIR, HOMA-IR > 2.5) and nine lean insulin-sensitive (LIS, HOMA-IR < 1.0) normoglycemic males. Of 374 circulating miRNAs we profiled, 65 species increased and 73 species decreased in the OIR compared to the LIS subjects, suggesting that the overall balance of the miRNA secretome is shifted in the OIR subjects. We also observed that 40 plasma proteins increased and 4 plasma proteins decreased in the OIR subjects compared to the LIS subjects, and most proteins are involved in metabolic and endocytic functions. We used an integrative -omics analysis framework called iOmicsPASS to link differentially regulated miRNAs with their target genes on the TargetScan map and the human protein interactome. Combined with tissue of origin information, the integrative analysis allowed us to nominate obesity-dependent and obesity-independent protein markers, along with potential sites of post-transcriptional regulation by some of the miRNAs. We also observed the changes in each -omics platform that are not linked by the TargetScan map, suggesting that proteins and microRNAs provide orthogonal information for the progression of OIR. In summary, our integrative analysis provides a network of elevated plasma markers of OIR and a global shift of microRNA secretome composition in the blood plasma.
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It is widely accepted that chronic stress may alter the homeostatic mechanisms of body weight control. In this study, we followed the metabolic changes occurring in mice when chronic stress caused by psychosocial defeat (CPD) is associated with ad libitum exposure to a palatable high-fat diet (HFD). In this model, CPD mice consumed more HFD than unstressed (Un) mice without gaining body weight. We focused on metabolic processes involved in weight control, such as de novo lipogenesis (DNL), fatty acid ß-oxidation (FAO), and thermogenesis. The activity and expression of DNL enzymes were reduced in the liver and white adipose tissue of mice consuming the HFD. Such effects were particularly evident in stressed mice. In both CPD and Un mice, HFD consumption increased the hepatic expression of the mitochondrial FAO enzyme carnitine palmitoyltransferase-1. In the liver of mice consuming the HFD, stress exposure prevented accumulation of triacylglycerols; however, accumulation of triacylglycerols was observed in Un mice under the same dietary regimen. In brown adipose tissue, stress increased the expression of uncoupling protein-1, which is involved in energy dissipation, both in HFD and control diet-fed mice. We consider increased FAO and energy dissipation responsible for the antiobesity effect seen in CPD/HFD mice. However, CPD associated with HFD induced hepatic oxidative stress.-Giudetti, A. M., Testini, M., Vergara, D., Priore, P., Damiano, F., Gallelli, C. A., Romano, A., Villani, R., Cassano, T., Siculella, L., Gnoni, G. V., Moles, A., Coccurello, R., Gaetani, S. Chronic psychosocial defeat differently affects lipid metabolism in liver and white adipose tissue and induces hepatic oxidative stress in mice fed a high-fat diet.
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Tejido Adiposo Blanco/metabolismo , Dieta Alta en Grasa , Metabolismo de los Lípidos , Hígado/metabolismo , Estrés Oxidativo , Estrés Psicológico , Acetil-CoA Carboxilasa/metabolismo , Tejido Adiposo Pardo/enzimología , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/enzimología , Animales , Peso Corporal , Carnitina O-Palmitoiltransferasa/genética , Carnitina O-Palmitoiltransferasa/metabolismo , Modelos Animales de Enfermedad , Ingestión de Energía , Ácido Graso Sintasas/metabolismo , Ácidos Grasos/metabolismo , Glutatión/metabolismo , Hígado/enzimología , Masculino , Ratones , Ratones Endogámicos BALB C , ARN Mensajero/genética , Proteína Desacopladora 1/metabolismoRESUMEN
Firefly luciferases produce yellow-green light under physiological and alkaline conditions, however at acidic pH, higher temperatures or in the presence of heavy metals the color changes to red, a property called pH-sensitivity. Despite many decades of studies, the proton and metal binding sites responsible for pH-sensitivity remain enigmatic. Previously we suggested that the salt bridge E311/R337 keeps a closed conformation of the luciferin phenolate binding site. Here we further investigated the effect of this salt bridge and mutations of the neighbor residues H310 and E/N354, on metal and pH-sensitivity of firefly luciferases emitting distinct bioluminescence colors (Cratomorphus distinctus: 548 nm; Macrolampis sp2: 569 nm). The substitutions of H310 and E/N354 modulate metal sensitivity, whereas the carboxylate of E311 may work as the catalytic base essential for green bioluminescence and pH-sensitivity. Modeling studies showed that H310, E311 and E354 side-chains coordinate Zinc, constituting the metal binding site and the pH-sensor. Electrostatic potential and pKa calculations suggest that the external couple H310/E354 is affected by pH, whereas E311/R337 make a stabilized internal pair which retains excited oxyluciferin ejected proton near its phenolate group into a high energy state, promoting yellow-green bioluminescence. Protonation or metal binding weaken these electrostatic gates and their ability to retain the excited oxyluciferin released proton near its phenolate, promoting red light emission.
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Acetyl-CoA carboxylase 1 (ACC1) is a cytosolic enzyme catalyzing the rate limiting step in de novo fatty acid biosynthesis. There is mounting evidence showing that ACC1 is susceptible to dysregulation and that it is over-expressed in liver diseases associated with lipid accumulation and in several cancers. In the present study, ACC1 regulation at the translational level is reported. Using several experimental approaches, the presence of an internal ribosome entry site (IRES) has been established in the 5' untranslated region (5' UTR) of the ACC1 mRNA. Transfection experiments with the ACC1 5' UTR inserted in a dicistronic reporter vector show a remarkable increase in the downstream cistron translation, through a cap-independent mechanism. The endoplasmic reticulum (ER) stress condition and the related unfolded protein response (UPR), triggered by treatment with thapsigargin and tunicamycin, cause an increase of the cap-independent translation of ACC1 mRNA in HepG2 cells, despite the overall reduction in global protein synthesis. Other stress conditions, such as serum starvation and incubation with hypoxia mimetic agent CoCl2, up-regulate ACC1 expression in HepG2 cells at the translational level. Overall, these findings indicate that the presence of an IRES in the ACC1 5' UTR allows ACC1 mRNA translation in conditions that are inhibitory to cap-dependent translation. A potential involvement of the cap-independent translation of ACC1 in several pathologies, such as obesity and cancer, has been discussed.
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Acetil-CoA Carboxilasa/genética , Cobalto/farmacología , Estrés del Retículo Endoplásmico/efectos de los fármacos , Sitios Internos de Entrada al Ribosoma/genética , Biosíntesis de Proteínas , Regiones no Traducidas 5'/genética , Acetil-CoA Carboxilasa/metabolismo , Hipoxia de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Medio de Cultivo Libre de Suero , Células Hep G2 , Humanos , Plásmidos/metabolismo , Biosíntesis de Proteínas/efectos de los fármacos , Empalme del ARN/genética , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
Mammalian genomes are well established, and highly conserved regions within odorant receptors that are unique from other G-protein coupled receptors have been identified. Numerous functional studies have focused on specific conserved amino acids motifs; however, not all conserved motifs have been sufficiently characterized. Here, we identified a highly conserved 18 amino acid sequence motif within transmembrane domain seven (CAS-TM7) which was identified by aligning odorant receptor sequences. Next, we investigated the expression pattern and distribution of this conserved amino acid motif among a broad range of odorant receptors. To examine the localization of odorant receptor proteins, we used a sequence-specific peptide antibody against CAS-TM7 which is specific to odorant receptors across species. The specificity of this peptide antibody in recognizing odorant receptors has been confirmed in a heterologous in vitro system and a rat-based in vivo system. The CAS-TM7 odorant receptors localized with distinct patterns at each region of the olfactory epithelium; septum, endoturbinate and ectoturbinate. To our great interests, we found that the CAS-TM7 odorant receptors are primarily localized to the dorsal region of the olfactory bulb, coinciding with olfactory epithelium-based patterns. Also, these odorant receptors were ectopically expressed in the various non-olfactory tissues in an evolutionary constrained manner between human and rats. This study has characterized the expression patterns of odorant receptors containing particular amino acid motif in transmembrane domain 7, and which led to an intriguing possibility that the conserved motif of odorant receptors can play critical roles in other physiological functions as well as olfaction.
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Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia Conservada , Células HEK293 , Humanos , Masculino , Dominios Proteicos , Ratas , Ratas Sprague-Dawley , Olfato/genéticaRESUMEN
OBJECTIVE: The objective of this review was to assess the level of risk of breast cancer for women exposed to ovulation-inducing therapy (OIT). METHODS: The 25 selected studies were extracted from the PUBMED database from January 2000 until March 2016 with the following key-words: "fertility agents", "infertility treatments", "clomiphene citrate", "buserelin", "ovarian stimulation", "assisted reproductive technology" and "breast cancer". Our meta-analysis was performed using Review Manager software, Cochrane Collaboration, 2014. The results were calculated by type of OIT, as well as globally. RESULTS: The analysis of these published epidemiological studies confirms that exposition to OIT is not a breast cancer risk factor, but the results are contradictory. Two studies have shown a significantly increased risk of breast cancer in a population of infertile women, while two others have found a significant decrease of this risk. The twenty others did not show any impact of IOT over this risk. Our meta-analysis of 20 selected studies has not identified a significant association between exposition to OIT and breast cancer risk (relative risk=0,96; IC 95: (0,81-1,14) for cohort studies and odds ratio=0,94; IC 95% (0,81-1,10) for case-control studies). CONCLUSION: Exposition to OIT is not an identified risk factor for breast cancer. A message reassuring about a possible risk of OIT-related breast cancer should be given to these women. Exposition to OIT is therefore not an indication of increased breast surveillance.
Asunto(s)
Neoplasias de la Mama/epidemiología , Infertilidad Femenina/terapia , Inducción de la Ovulación/efectos adversos , Neoplasias de la Mama/etiología , Buserelina/efectos adversos , Clomifeno/efectos adversos , Femenino , Fármacos para la Fertilidad/efectos adversos , Humanos , Inducción de la Ovulación/métodos , Técnicas Reproductivas Asistidas , Factores de RiesgoRESUMEN
Cyclic AMP (cAMP) and protein kinase A (PKA), classical examples of spatially compartmentalized signaling molecules, are critical axon determinants that regulate neuronal polarity and axon formation, yet little is known about micro-compartmentalization of cAMP and PKA signaling and its role in developing neurons. Here, we revealed that cAMP forms a gradient in developing hippocampal neurons, with higher cAMP levels in more distal regions of the axon compared to other regions of the cell. Interestingly, this cAMP gradient changed according to the developmental stage and depended on proper anchoring of PKA by A-kinase anchoring proteins (AKAPs). Disrupting PKA anchoring to AKAPs increased the cAMP gradient in early-stage neurons and led to enhanced axon elongation. Our results provide new evidence for a local negative-feedback loop, assembled by AKAPs, for the precise control of a growth-stage-dependent cAMP gradient to ensure proper axon growth.