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1.
Proc Natl Acad Sci U S A ; 120(15): e2218142120, 2023 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-37023123

RESUMEN

The internal state of an animal, including homeostatic requirements, modulates its behavior. Negative energy balance stimulates hunger, thus promoting a range of actions aimed at obtaining food. While these survival actions are well established, the influence of the energy status on prosocial behavior remains unexplored. We developed a paradigm to assess helping behavior in which a free mouse was faced with a conspecific trapped in a restrainer. We measured the willingness of the free mouse to liberate the confined mouse under diverse metabolic conditions. Around 42% of ad libitum-fed mice exhibited a helping behavior, as evidenced by the reduction in the latencies to release the trapped cagemate. This behavior was independent of subsequent social contact reward and was associated with changes in corticosterone indicative of emotional contagion. This decision-making process was coupled with reduced blood glucose excursions and higher Adenosine triphosphate (ATP):Adenosine diphosphate (ADP) ratios in the forebrain of helper mice, suggesting that it was a highly energy-demanding process. Interestingly, chronic (food restriction and type 2 diabetes) and acute (chemogenetic activation of hunger-promoting AgRP neurons) situations mimicking organismal negative energy balance and enhanced appetite attenuated helping behavior toward a distressed conspecific. To investigate similar effects in humans, we estimated the influence of glycated hemoglobin (a surrogate of long-term glycemic control) on prosocial behavior (namely charity donation) using the Understanding Society dataset. Our results evidenced that organismal energy status markedly influences helping behavior and that hypothalamic AgRP neurons are at the interface of metabolism and prosocial behavior.


Asunto(s)
Metabolismo Energético , Conducta de Ayuda , Animales , Ratones , Glucemia/metabolismo , Adenosina Trifosfato/metabolismo , Adenosina Difosfato/metabolismo , Prosencéfalo/metabolismo , Hambre , Hemoglobina Glucada/análisis , Hipotálamo/metabolismo , Control Glucémico , Ratones Endogámicos C57BL , Masculino , Humanos , Organizaciones de Beneficencia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Experimental/metabolismo , Estreptozocina
2.
Curr Biol ; 32(21): 4699-4706.e4, 2022 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-36182699

RESUMEN

Loss of appetite and negative energy balance are common features of endotoxemia in all animals and are thought to have protective roles by reducing nutrient availability to host and pathogen metabolism. Accordingly, fasting and caloric restriction have well-established anti-inflammatory properties. However, in response to reduced nutrient availability at the cellular and organ levels, negative energy balance also recruits distinct energy-sensing brain circuits, but it is not known whether these neuronal systems have a role in its anti-inflammatory effects. Here, we report that hypothalamic AgRP neurons-a critical neuronal population for the central representation of negative energy balance-have parallel immunoregulatory functions. We found that when endotoxemia occurs in fasted mice, the activity of AgRP neurons remains sustained, but this activity does not influence feeding behavior and endotoxemic anorexia. Furthermore, we found that endotoxemia acutely desensitizes AgRP neurons, which also become refractory to inhibitory signals. Mimicking this sustained AgRP neuron activity in fed mice by chemogenetic activation-a manipulation known to recapitulate core behavioral features of fasting-results in reduced acute tumor necrosis factor alpha (TNF-α) release during endotoxemia. Mechanistically, we found that endogenous glucocorticoids play an important role: glucocorticoid receptor deletion from AgRP neurons prevents their endotoxemia-induced desensitization, and importantly, it counteracts the fasting-induced suppression of TNF-α release, resulting in prolonged sickness. Together, these findings provide evidence directly linking AgRP neuron activity to the acute response during endotoxemia, suggesting that these neurons are a functional component of the immunoregulatory effects associated with negative energy balance and catabolic metabolism.


Asunto(s)
Endotoxemia , Factor de Necrosis Tumoral alfa , Ratones , Animales , Proteína Relacionada con Agouti/genética , Proteína Relacionada con Agouti/metabolismo , Factor de Necrosis Tumoral alfa/genética , Endotoxemia/metabolismo , Endotoxemia/patología , Hipotálamo/metabolismo , Neuronas/fisiología , Metabolismo Energético
3.
Cell Metab ; 33(5): 888-904.e6, 2021 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-33667386

RESUMEN

The protein leverage hypothesis predicts that low dietary protein should increase energy intake and cause adiposity. We designed 10 diets varying from 1% to 20% protein combined with either 60% or 20% fat. Contrasting the expectation, very low protein did not cause increased food intake. Although these mice had activated hunger signaling, they ate less food, resulting in decreased body weight and improved glucose tolerance but not increased frailty, even under 60% fat. Moreover, they did not show hyperphagia when returned to a 20% protein diet, which could be mimicked by treatment with rapamycin. Intracerebroventricular injection of AAV-S6K1 significantly blunted the decrease in both food intake and body weight in mice fed 1% protein, an effect not observed with inhibition of eIF2a, TRPML1, and Fgf21 signaling. Hence, the 1% protein diet induced decreased food intake and body weight via a mechanism partially dependent on hypothalamic mTOR signaling.


Asunto(s)
Dieta con Restricción de Proteínas , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Factor de Transcripción Activador 4/genética , Factor de Transcripción Activador 4/metabolismo , Tejido Adiposo Blanco/metabolismo , Animales , Ingestión de Alimentos , Metabolismo Energético , Factores de Crecimiento de Fibroblastos/genética , Factores de Crecimiento de Fibroblastos/metabolismo , Expresión Génica , Prueba de Tolerancia a la Glucosa , Hiperfagia/tratamiento farmacológico , Hipotálamo/metabolismo , Leptina/sangre , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacos , Sirolimus/farmacología , Sirolimus/uso terapéutico , Pérdida de Peso
4.
Mol Autism ; 11(1): 88, 2020 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-33208191

RESUMEN

BACKGROUND: Autism spectrum disorder (ASD) is a highly prevalent neurodevelopmental condition affecting almost 1% of children, and represents a major unmet medical need with no effective drug treatment available. Duplication at 7q11.23 (7Dup), encompassing 26-28 genes, is one of the best characterized ASD-causing copy number variations and offers unique translational opportunities, because the hemideletion of the same interval causes Williams-Beuren syndrome (WBS), a condition defined by hypersociability and language strengths, thereby providing a unique reference to validate treatments for the ASD symptoms. In the above-indicated interval at 7q11.23, defined as WBS critical region, several genes, such as GTF2I, BAZ1B, CLIP2 and EIF4H, emerged as critical for their role in the pathogenesis of WBS and 7Dup both from mouse models and human studies. METHODS: We performed a high-throughput screening of 1478 compounds, including central nervous system agents, epigenetic modulators and experimental substances, on patient-derived cortical glutamatergic neurons differentiated from our cohort of induced pluripotent stem cell lines (iPSCs), monitoring the transcriptional modulation of WBS interval genes, with a special focus on GTF2I, in light of its overriding pathogenic role. The hits identified were validated by measuring gene expression by qRT-PCR and the results were confirmed by western blotting. RESULTS: We identified and selected three histone deacetylase inhibitors (HDACi) that decreased the abnormal expression level of GTF2I in 7Dup cortical glutamatergic neurons differentiated from four genetically different iPSC lines. We confirmed this effect also at the protein level. LIMITATIONS: In this study, we did not address the molecular mechanisms whereby HDAC inhibitors act on GTF2I. The lead compounds identified will now need to be advanced to further testing in additional models, including patient-derived brain organoids and mouse models recapitulating the gene imbalances of the 7q11.23 microduplication, in order to validate their efficacy in rescuing phenotypes across multiple functional layers within a translational pipeline towards clinical use. CONCLUSIONS: These results represent a unique opportunity for the development of a specific class of compounds for treating 7Dup and other forms of intellectual disability and autism.


Asunto(s)
Trastorno del Espectro Autista/patología , Corteza Cerebral/patología , Duplicación Cromosómica/genética , Cromosomas Humanos Par 7/genética , Ensayos Analíticos de Alto Rendimiento , Inhibidores de Histona Desacetilasas/farmacología , Neuronas/patología , Factores de Transcripción TFII/genética , Trastorno del Espectro Autista/genética , Cromosomas Humanos Par 7/metabolismo , Variaciones en el Número de Copia de ADN/genética , Evaluación Preclínica de Medicamentos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/metabolismo , Neurogénesis/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Transcripción TFII/metabolismo , Transcripción Genética/efectos de los fármacos
5.
Am J Clin Oncol ; 43(9): 628-635, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32889832

RESUMEN

OBJECTIVES: Stereotactic body radiation treatment represents an intriguing therapeutic option for patients with early-stage prostate cancer. In this phase II study, stereotactic body radiation treatment was delivered by volumetric modulated arc therapy with flattening filter free beams and was gated using real-time electromagnetic transponder system to maximize precision of radiotherapy and, potentially, to reduce toxicities. MATERIALS AND METHODS: Patients affected by histologically proven prostate adenocarcinoma and National Comprehensive Cancer Network (NCCN) intermediate class of risk were enrolled in this phase II study. Beacon transponders were positioned transrectally within the prostate parenchyma 7 to 10 days before simulation computed tomography scan. The radiotherapy schedule was 38 Gy in 4 fractions delivered every other day. Toxicity assessment was performed according to Common Terminology Criteria for Adverse Events (CTCAE), v4.0. RESULTS: Thirty-six patients were enrolled in this study. Median initial prostate-specific antigen was 7.0 ng/mL (range: 2.3 to 14.0 ng/mL). Median nadir-prostate-specific antigen after treatment was 0.2 ng/mL (range: 0.006 to 4.8 ng/mL). A genitourinary acute toxicity was observed in 21 patients (dysuria grade [G] 1: 41.7%, G2: 16.7%). Gastrointestinal acute toxicity was found in 9 patients (proctitis G1: 19.4%, G2: 5.6%). Late toxicity was mild (genitourinary toxicity G1: 30.6%; G2: 8.3%; gastrointestinal toxicity G1: 13.9%; G2: 19.4%). At a median follow-up time of 41 months, 3 biochemical recurrences were observed (2 local recurrences, 1 distant metastasis). Three-year biochemical recurrence-free survival was 89.8% (International Society of Urologic Pathology Grade Group 2: 100%, Grade Group 3: 77.1%, P=0.042). CONCLUSION: Ultrahypofractionated radiotherapy, delivered with flattening filter free-volumetric modulated arc therapy and gated by electromagnetic transponders, is a valid option for intermediate-risk prostate cancer.


Asunto(s)
Adenocarcinoma/radioterapia , Recurrencia Local de Neoplasia/sangre , Neoplasias de la Próstata/radioterapia , Radiocirugia/métodos , Radioterapia de Intensidad Modulada , Adenocarcinoma/secundario , Anciano , Diarrea/etiología , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Disuria/etiología , Fenómenos Electromagnéticos , Humanos , Masculino , Persona de Mediana Edad , Nocturia/etiología , Proctitis/etiología , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/patología , Traumatismos por Radiación/etiología , Radiocirugia/efectos adversos , Radioterapia de Intensidad Modulada/efectos adversos
6.
Strahlenther Onkol ; 196(7): 608-616, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32303782

RESUMEN

INTRODUCTION: Stereotactic body radiation therapy (SBRT) is considered an effective and safe treatment in patients with low- and intermediate-risk prostate cancer (PC). However, due to a lack of long-term follow-up and late toxicity data, this treatment is not universally accepted. The present study aimed to evaluate outcome and early and late toxicity in a cohort of patients with low- and intermediate-risk PC treated prospectively with linear accelerator (linac)-based SBRT. PATIENTS AND METHODS: Patients with low- or intermediate-risk (NCCN criteria) PC were included. All patients received linac-based SBRT to 35 Gy in 5 fractions delivered on alternate days. Endpoints were toxicity, biochemical relapse-free survival (BRFS), metastatic progression-free survival (mPFS), and overall survival (OS). RESULTS: From 2012 to 2018, 178 patients were treated. Median baseline prostate-specific antigen (iPSA) was 6.37 ng/ml (range 1.78-20). Previous transurethral resection of the prostate (TURP) was present in 23 (12.9%) patients. Median follow-up was 58.9 months (range 9.7-89.9). BRFS rates at 1, 3, and 5 years were 98.3 (95% confidence interval, CI, 94.7-99.4%), 94.4 (95%CI 89.4-97), and 91.6% (95%CI 85.4-95.2), respectively. In univariate analysis, performance status (PS), iPSA, and nadir PSA (nPSA) were correlated with BRFS. In multivariable analysis iPSA and nPSA remained significant. BRFS rates at 5 years were 94.9% (95%CI 86.8-98) for International Society of Urological Pathology (ISUP) grade group 1, 93.2% (95%CI 80.5-97.7) for ISUP group 2, and 74.8% (95%CI 47.1-89.5) for ISUP group 3. At 1, 3, and 5 years, mPFS rates were 98.8 (95%CI 95.5-99.7), 96.2 (95%CI 91.9-98.3), and 92.9% (95%CI 87.2-96.2), respectively; OS rates were 100, 97.2 (95%CI 92.9-98.9), and 95.1% (95%CI 90-97.6), respectively. One (0.56%) case of grade 3 acute genitourinary (GU), one case of acute gastrointestinal (GI), and one case of grade 3 late GU toxicity were observed. GI toxicity positively correlated with prostate volume. CONCLUSION: At long-term follow-up, linac-based SBRT continues to be a valid option for the management localized PC. Biochemical control remains high at 5 years, albeit with some concerns regarding the optimal schedule for unfavorable intermediate-risk PC. Considering the excellent prognosis, patient selection is crucial for prevention of severe late toxicity.


Asunto(s)
Adenocarcinoma/radioterapia , Neoplasias de la Próstata/radioterapia , Radiocirugia/métodos , Adenocarcinoma/sangre , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Anciano , Anciano de 80 o más Años , Terapia Combinada , Fraccionamiento de la Dosis de Radiación , Enfermedades Gastrointestinales/etiología , Ultrasonido Enfocado de Alta Intensidad de Ablación , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Aceleradores de Partículas , Supervivencia sin Progresión , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Radiocirugia/efectos adversos , Factores de Riesgo , Resección Transuretral de la Próstata , Resultado del Tratamiento , Carga Tumoral , Trastornos Urinarios/etiología
7.
Psychoneuroendocrinology ; 109: 104407, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31445429

RESUMEN

The cannabinoid-1 receptor (CB1) plays a critical role in a number of biological processes including nutrient intake, addiction and anxiety-related behaviour. Numerous studies have shown that expression of the gene encoding CB1 (CNR1) is highly dynamic with changes in the tissue specific expression of CNR1 associated with brain homeostasis and disease progression. However, little is known of the mechanisms regulating this dynamic expression. To gain a better understanding of the genomic mechanisms modulating the expression of CNR1 in health and disease we characterised the role of a highly conserved regulatory sequence (ECR1) in CNR1 intron 2 that contained a polymorphism in linkage disequilibrium with disease associated SNPs. We used CRISPR/CAS9 technology to disrupt ECR1 within the mouse genome. Disruption of ECR1 significantly reduced CNR1 expression in the hippocampus but not in the hypothalamus. These mice also displayed an altered sex-specific anxiety-related behavioural profile (open field test), reduced ethanol intake and a reduced hypothermic response following CB1 agonism. However, no significant changes in feeding patterns were detected. These data suggest that, whilst not all of the expression of CNR1 is modulated by ECR1, this highly conserved enhancer is required for appropriate physiological responses to a number of stimuli. The combination of comparative genomics and CRISPR/CAS9 disruption used in our study to determine the functional effects of genetic and epigenetic changes on the activity of tissue-specific regulatory elements at the CNR1 locus represent an important first step in gaining a mechanistic understanding of cannabinoid regulatory pharmacogenetics.


Asunto(s)
Consumo de Bebidas Alcohólicas/genética , Conducta Adictiva/genética , Receptor Cannabinoide CB1/genética , Animales , Ansiedad/genética , Trastornos de Ansiedad/genética , Encéfalo/metabolismo , Cannabinoides/genética , Femenino , Predisposición Genética a la Enfermedad/genética , Genotipo , Hipocampo/metabolismo , Hipotálamo/metabolismo , Intrones/genética , Desequilibrio de Ligamiento/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Polimorfismo de Nucleótido Simple/genética , Receptor Cannabinoide CB1/metabolismo
8.
Nucl Med Commun ; 39(10): 951-956, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30124599

RESUMEN

BACKGROUND: In the era of image-guided radiotherapy, PET has become an important tool for tumor delineation in several types of cancer. The aim of this study was to evaluate the effect of this imaging modality in treatment planning of a cohort of patients with prostate cancer eligible for radiotherapy. METHODS: From September 2011 to January 2016, 135 consecutive patients (median age 69 years, range: 53-89) were referred to our department for radiation therapy with radical intent (n=28), for postoperative adjuvant (n=13) or salvage treatment (n=50), for re-irradiation (n=19), or for radiotherapy on oligometastases (n=25). Before planning the radiotherapy course, patients were submitted to carbon-11-choline PET (Cho-PET) to confirm the indication to radiotherapy and the irradiation volumes. RESULTS: Among the 135 patients subjected to Cho-PET, the indication to radiotherapy was modified in 66 (48.8%) cases based on the Cho-PET result. In particular, Cho-PET helped to better define the radiotherapy programme in 12 out of 28 (42.8%) patients who were candidates for primary radiation therapy, 33 (52.4%) of 63 patients undergoing adjuvant/salvage radiotherapy, and 21 out of 44 (47.7%) patients with relapsed/metastatic disease. Overall biochemical response is documented by mean and median prostate specific antigen values, which changed from 15.29 to 4.00 ng/ml, respectively, before to mean 4.74 ng/ml and median 0.81 ng/ml after therapy (P=0.05). CONCLUSION: In our series, Cho-PET had a significant effect on radiotherapy planning of patients affected by prostate cancer, determining a change in management in 48.8% of cases, considering all therapeutic indications.


Asunto(s)
Radioisótopos de Carbono , Colina , Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/radioterapia , Planificación de la Radioterapia Asistida por Computador , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad
9.
Nature ; 537(7618): 97-101, 2016 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-27556938

RESUMEN

Serotonin (also known as 5-hydroxytryptamine (5-HT)) is a neurotransmitter that has an essential role in the regulation of emotion. However, the precise circuits have not yet been defined through which aversive states are orchestrated by 5-HT. Here we show that 5-HT from the dorsal raphe nucleus (5-HTDRN) enhances fear and anxiety and activates a subpopulation of corticotropin-releasing factor (CRF) neurons in the bed nucleus of the stria terminalis (CRFBNST) in mice. Specifically, 5-HTDRN projections to the BNST, via actions at 5-HT2C receptors (5-HT2CRs), engage a CRFBNST inhibitory microcircuit that silences anxiolytic BNST outputs to the ventral tegmental area and lateral hypothalamus. Furthermore, we demonstrate that this CRFBNST inhibitory circuit underlies aversive behaviour following acute exposure to selective serotonin reuptake inhibitors (SSRIs). This early aversive effect is mediated via the corticotrophin-releasing factor type 1 receptor (CRF1R, also known as CRHR1), given that CRF1R antagonism is sufficient to prevent acute SSRI-induced enhancements in aversive learning. These results reveal an essential 5-HTDRN→CRFBNST circuit governing fear and anxiety, and provide a potential mechanistic explanation for the clinical observation of early adverse events to SSRI treatment in some patients with anxiety disorders.


Asunto(s)
Amígdala del Cerebelo/metabolismo , Ansiedad/metabolismo , Hormona Liberadora de Corticotropina/metabolismo , Miedo/fisiología , Serotonina/metabolismo , Tálamo/metabolismo , Amígdala del Cerebelo/efectos de los fármacos , Animales , Ansiedad/inducido químicamente , Trastornos de Ansiedad/inducido químicamente , Núcleo Dorsal del Rafe/efectos de los fármacos , Núcleo Dorsal del Rafe/metabolismo , Miedo/efectos de los fármacos , Femenino , Fluoxetina/efectos adversos , Fluoxetina/farmacología , Hipotálamo/efectos de los fármacos , Hipotálamo/metabolismo , Masculino , Ratones , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Optogenética , Receptores de Hormona Liberadora de Corticotropina/metabolismo , Inhibidores Selectivos de la Recaptación de Serotonina/efectos adversos , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Tálamo/efectos de los fármacos , Área Tegmental Ventral/efectos de los fármacos , Área Tegmental Ventral/metabolismo
10.
Anticancer Res ; 36(7): 3451-7, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27354607

RESUMEN

BACKGROUND/AIM: Radiotherapy is a common approach for treating squamous cell carcinoma (SCC) of the oropharynx. We aimed to analyze toxicity and outcome of patients affected by oropharyngeal SCC treated with volumetric modulated arc therapy (VMAT). PATIENTS AND METHODS: Fifty-four patients presenting advanced orophayngeal carcinoma who were treated with radical radiotherapy were analyzed. All patients were treated with VMAT-RapidArc, with simultaneous integrated boost in 33 fractions for a dose of 69.96 Gy to the high-risk, and of 54.45 Gy to the low-risk volume. RESULTS: Median follow-up was 23 months. In eight cases, locoregional relapse was observed (median time to relapse=10.7 months). Four among eight local recurrences appeared in the high-dose target volume. The 1- and 2-year actuarial disease-free survival rates were 88% and 80%, respectively. The 1- and 2-year actuarial overall survival rates were 94% and 87%, respectively. CONCLUSION: VMAT for oropharyngeal SCC treatment is effective and safe, with interesting rates of control of disease and survival.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Neoplasias Orofaríngeas/radioterapia , Radioterapia de Intensidad Modulada/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carboplatino/administración & dosificación , Carcinoma de Células Escamosas/mortalidad , Cetuximab/administración & dosificación , Quimioradioterapia , Cisplatino/administración & dosificación , Fraccionamiento de la Dosis de Radiación , Femenino , Fluorouracilo/administración & dosificación , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Neoplasias Orofaríngeas/mortalidad , Radiodermatitis/etiología , Resultado del Tratamiento , Xerostomía/etiología
11.
Dis Model Mech ; 9(4): 401-12, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26769798

RESUMEN

Although obesity is a global epidemic, the physiological mechanisms involved are not well understood. Recent advances reveal that susceptibility to obesity can be programmed by maternal and neonatal nutrition. Specifically, a maternal low-protein diet during pregnancy causes decreased intrauterine growth, rapid postnatal catch-up growth and an increased risk for diet-induced obesity. Given that the synthesis of the neurotransmitter 5-hydroxytryptamine (5-HT) is nutritionally regulated and 5-HT is a trophic factor, we hypothesised that maternal diet influences fetal 5-HT exposure, which then influences development of the central appetite network and the subsequent efficacy of 5-HT to control energy balance in later life. Consistent with our hypothesis, pregnant rats fed a low-protein diet exhibited elevated serum levels of 5-HT, which was also evident in the placenta and fetal brains at embryonic day 16.5. This increase was associated with reduced levels of 5-HT2CR, the primary 5-HT receptor influencing appetite, in the fetal, neonatal and adult hypothalamus. As expected, a reduction of 5-HT2CR was associated with impaired sensitivity to 5-HT-mediated appetite suppression in adulthood. 5-HT primarily achieves effects on appetite by 5-HT2CR stimulation of pro-opiomelanocortin (POMC) peptides within the arcuate nucleus of the hypothalamus (ARC). We show that 5-HT2ARs are also anatomically positioned to influence the activity of ARC POMC neurons and that mRNA encoding 5-HT2AR is increased in the hypothalamus ofin uterogrowth-restricted offspring that underwent rapid postnatal catch-up growth. Furthermore, these animals at 3 months of age are more sensitive to appetite suppression induced by 5-HT2AR agonists. These findings not only reveal a 5-HT-mediated mechanism underlying the programming of susceptibility to obesity, but also provide a promising means to correct it, by treatment with a 5-HT2AR agonist.


Asunto(s)
Crecimiento y Desarrollo , Hipotálamo/metabolismo , Receptor de Serotonina 5-HT2A/metabolismo , Receptor de Serotonina 5-HT2C/metabolismo , Animales , Animales Recién Nacidos , Núcleo Arqueado del Hipotálamo/efectos de los fármacos , Núcleo Arqueado del Hipotálamo/metabolismo , Peso Corporal/efectos de los fármacos , Proteínas en la Dieta/farmacología , Conducta Alimentaria/efectos de los fármacos , Femenino , Fenfluramina/administración & dosificación , Fenfluramina/farmacología , Feto/efectos de los fármacos , Feto/metabolismo , Crecimiento y Desarrollo/efectos de los fármacos , Hipotálamo/anatomía & histología , Hipotálamo/efectos de los fármacos , Hipotálamo/crecimiento & desarrollo , Captura por Microdisección con Láser , Masculino , Neuronas/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Tamaño de los Órganos/efectos de los fármacos , Embarazo , Ratas Wistar , Reproducibilidad de los Resultados , Serotonina/metabolismo , Factores de Tiempo , Triptófano/metabolismo
12.
Proc Natl Acad Sci U S A ; 111(32): 11876-81, 2014 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-25071172

RESUMEN

Prolyl endopeptidase (PREP) has been implicated in neuronal functions. Here we report that hypothalamic PREP is predominantly expressed in the ventromedial nucleus (VMH), where it regulates glucose-induced neuronal activation. PREP knockdown mice (Prep(gt/gt)) exhibited glucose intolerance, decreased fasting insulin, increased fasting glucagon levels, and reduced glucose-induced insulin secretion compared with wild-type controls. Consistent with this, central infusion of a specific PREP inhibitor, S17092, impaired glucose tolerance and decreased insulin levels in wild-type mice. Arguing further for a central mode of action of PREP, isolated pancreatic islets showed no difference in glucose-induced insulin release between Prep(gt/gt) and wild-type mice. Furthermore, hyperinsulinemic euglycemic clamp studies showed no difference between Prep(gt/gt) and wild-type control mice. Central PREP regulation of insulin and glucagon secretion appears to be mediated by the autonomic nervous system because Prep(gt/gt) mice have elevated sympathetic outflow and norepinephrine levels in the pancreas, and propranolol treatment reversed glucose intolerance in these mice. Finally, re-expression of PREP by bilateral VMH injection of adeno-associated virus-PREP reversed the glucose-intolerant phenotype of the Prep(gt/gt) mice. Taken together, our results unmask a previously unknown player in central regulation of glucose metabolism and pancreatic function.


Asunto(s)
Glucagón/metabolismo , Hipotálamo/enzimología , Insulina/metabolismo , Serina Endopeptidasas/metabolismo , Animales , Glucemia/metabolismo , Expresión Génica , Técnicas de Silenciamiento del Gen , Técnica de Clampeo de la Glucosa , Intolerancia a la Glucosa/enzimología , Intolerancia a la Glucosa/etiología , Hipotálamo/fisiología , Indoles/farmacología , Secreción de Insulina , Canales Iónicos/genética , Masculino , Ratones , Ratones Transgénicos , Proteínas Mitocondriales/genética , Páncreas/metabolismo , Fosforilación , Prolil Oligopeptidasas , Receptor de Insulina/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Serina Endopeptidasas/deficiencia , Serina Endopeptidasas/genética , Inhibidores de Serina Proteinasa/farmacología , Tiazolidinas/farmacología , Proteína Desacopladora 1 , Núcleo Hipotalámico Ventromedial/enzimología , Núcleo Hipotalámico Ventromedial/fisiología
13.
Cell Metab ; 15(3): 299-310, 2012 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-22405068

RESUMEN

The endocannabinoid system plays a critical role in the control of energy homeostasis, but the identity and localization of the endocannabinoid signal involved remain unknown. In the present study, we developed transgenic mice that overexpress in forebrain neurons the presynaptic hydrolase, monoacylglycerol lipase (MGL), which deactivates the endocannabinoid 2-arachidonoyl-sn-glycerol (2-AG). MGL-overexpressing mice show a 50% decrease in forebrain 2-AG levels but no overt compensation in other endocannabinoid components. This biochemical abnormality is accompanied by a series of metabolic changes that include leanness, elevated energy cost of activity, and hypersensitivity to ß(3)-adrenergic-stimulated thermogenesis, which is corrected by reinstating 2-AG activity at CB(1)-cannabinoid receptors. Additionally, the mutant mice are resistant to diet-induced obesity and express high levels of thermogenic proteins, such as uncoupling protein 1, in their brown adipose tissue. The results suggest that 2-AG signaling through CB(1) regulates the activity of forebrain neural circuits involved in the control of energy dissipation.


Asunto(s)
Ácidos Araquidónicos/metabolismo , Metabolismo Energético/fisiología , Glicéridos/metabolismo , Prosencéfalo/metabolismo , Transducción de Señal/fisiología , Animales , Endocannabinoides , Metabolismo Energético/genética , Hipotálamo/metabolismo , Inmunohistoquímica , Ratones , Ratones Transgénicos , Monoacilglicerol Lipasas/genética , Monoacilglicerol Lipasas/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Transducción de Señal/genética
14.
Am J Clin Oncol ; 31(3): 280-4, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18525308

RESUMEN

OBJECTIVE: Aim of this study is to evaluate the feasibility of an accelerated fractionation radiotherapy by concomitant boost in locally advanced cervical cancer patients, to explore the maximum tolerated dose (MTD) of radiation through a dose-escalation scheme, and to verify if increasing the radiation dose would result in a higher rate of pathologic complete response. METHODS: During the first and the last week of treatment, a combination of cisplatin (20 mg/mq/d, IV, days 1-4) and 5-fluorouracil (1 g/mq/d, continuous venous infusion, days 1-4) was administered. The dose escalation of external radiotherapy was delivered on the primary tumor, using the concomitant boost technique (CB, 90 cGy per fraction), delivering 3 different dose levels: (1) 1 weekly boost for a total dose of 4320 cGy; (2) 2 weekly boosts, total dose 4680 cGy; (3) 3 weekly boosts, total dose of 5040 cGy. RESULTS: Eighteen patients were submitted to a radiochemotherapeutic schedule of 3960 cGy in 22 fractions on pelvic lymph nodal stations. The MTD of radiation was not reached, being the only toxicities registered neutropenia G3 (n = 4), thrombocytopenia G3 (n = 1), stomatitis G3 (n = 1), diarrhea G3 (n = 2) easily managed. Six weeks after the end of radiochemotherapy, 17 patients were submitted to radical surgery, and are therefore evaluable for pathologic response. Among them, 15 complete remissions (88.2%, including 3 microscopical partial response), 1 partial response (5.9%), and 1 progression (5.9%) have been observed. CONCLUSIONS: These results demonstrate, even if in a small study, that this regimen of concurrent chemoradiation followed by radical surgery is well tolerated.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/radioterapia , Adulto , Anciano , Quimioterapia Adyuvante , Cisplatino/administración & dosificación , Fraccionamiento de la Dosis de Radiación , Estudios de Factibilidad , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Metástasis Linfática , Dosis Máxima Tolerada , Persona de Mediana Edad , Estadificación de Neoplasias , Dosificación Radioterapéutica , Radioterapia Adyuvante , Inducción de Remisión , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/cirugía
15.
Tumori ; 91(4): 295-301, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16277092

RESUMEN

AIMS AND PURPOSE: This is a prospective, phase II study aimed to evaluate the effect of concurrent 5-fluorouracil, mitomycin C, and radiation with or without brachytherapy on the clinical outcome of a series of recurrent cervical cancer patients and to determine the prognostic impact of a subset of factors. METHODS: Thirty-three patients with locally recurrent, non-metastatic cervical cancer received external beam radiation (4-week split course: 23.4 + 23.4 Gy) plus two courses of concomitant chemotherapy (5-fluorouracil, 96-h continuous infusion, days 1-4, 1 g/m2/day; mitomycin C, 10 mg/m2, bolus i.v., day 1). Twelve patients with vaginal recurrence (36.4%) underwent endocavitary low-dose rate brachytherapy boost (20-25 Gy); 11 patients with lateral pelvic recurrence (33.3%) received external beam radiation boost (14-20 Gy). RESULTS: Fourteen complete responses (42.4%), 7 partial responses (21.2%), 5 disease stabilizations (15.1%) and 7 progressions (21.2%) were obtained. After a median follow-up of 34 months (range, 6-127), overall actuarial 3-year survival, progression-free survival and local progression-free survival were 59.7%, 48.1% and 51.7%, respectively. Patients with vaginal recurrence of less than 4 cm and negative lymph nodes proved to respond best to the treatment. Two patients (6.1%) experienced hematologic grade 3 toxicity. One patient had grade 3 intestinal toxicity (3.0%). No patient had major skin or urological acute toxicity. Severe late toxicity was infrequent. Three patients had prolonged leukopenia (9.0%). Four patients showed severe vaginal stenosis (12.1%). A clinical score of 0 to 1 was assigned to each patient on the basis of the absence (score = 0) or presence (score = 1) of any of the following prognostic factors: time between surgery and recurrence shorter than 12 months, pelvic wall site of recurrence, positive lymph nodes, hemoglobin < 11 g/dL. Using this system, it was clear that patients with a low total score had a significantly better outcome (clinical remission, 51% of patients with a score < or = 2 vs 12% of patients with a score > 2, P = 0.06), local control of the disease (65% vs 20% after 3 years, P = 0.001,) and overall survival (75% vs 30% after 3 years, P = 0.032). CONCLUSIONS: Our data suggest that this combined modality therapy was relatively well tolerated and resulted in reasonable local control and survival. The scoring system proved to be helpful to identify patients with the greatest chance of benefiting from the treatment. Further studies are probably needed to salvage the other patients, whose prognosis remains severe.


Asunto(s)
Antineoplásicos/uso terapéutico , Braquiterapia , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/radioterapia , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/radioterapia , Adulto , Anciano , Antineoplásicos/efectos adversos , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Fluorouracilo/administración & dosificación , Humanos , Persona de Mediana Edad , Mitomicina/administración & dosificación , Valor Predictivo de las Pruebas , Estudios Prospectivos , Radioterapia Adyuvante , Análisis de Supervivencia , Resultado del Tratamiento
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