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1.
Rev Panam Salud Publica ; 47: e156, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37901443

RESUMO

Objective: To highlight the objectives, achievements, challenges, and next steps for the World Health Organization's Global Initiative for Childhood Cancer (GICC) framework, a project designed to improve psychosocial care (PSC) in pediatric cancer centers across Latin America and the Caribbean (LAC). Methods: The project was launched in Peru, the first GICC focal country, in November 2020. The diagnosis phase included a survey and a semistructured interview with health professionals to assess PSC practices in institutions, and a needs assessment survey for caregivers. In the second phase, a strategic plan was developed to address the identified needs, including the adaptation of PSC standards, the establishment of multicenter working groups, the expansion of the proposal, and the development of materials. Results: The study found that PSC was not being adequately provided in accordance with international standards. Six adapted standards were proposed and validated, and more than 50 regional health professionals participated in online activities to support the project. The implementation process is currently ongoing, with the establishment of five multidisciplinary working groups, one regional committee, and the production of 16 technical outputs. Conclusion: This project represents a substantial step forward to improve PSC for pediatric patients with cancer and their families in LAC countries. The establishment of working groups and evidence-based interventions strengthen the proposal and its implementation. Development of health policies that include PSC according to standards is needed to achieve sustainable results in the quality of life of children with cancer and their families.

2.
Eur J Neurosci ; 45(10): 1325-1332, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28370506

RESUMO

Food intake during the rest phase promotes circadian desynchrony, which has been associated with metabolic diseases. However, the link between circadian rhythm and metabolic alterations is not well understood. To investigate this issue, we explored the circadian rhythm of c-Fos immunoreactivity (IR) in rats fed during the day, during the night or with free access to food for 3 weeks. The analysis was focused on the hypothalamic nuclei, which are interconnected and involved in the control of energy homeostasis and/or arousal: lateral hypothalamus (LH), perifornical area, arcuate, ventrolateral pre-optic (VLPO) and tuberomammillary nuclei. The results show that food intake during the rest phase flattened the circadian c-Fos expression in the LH and perifornical area, and induced a phase shift in the VLPO area. In addition, c-Fos expression was analyzed in the orexin and melanin-concentrating hormone (MCH) neurons of the LH, which are involved in the control of food intake and arousal, and in α-melanin-stimulating hormone and neuropeptide Y (NPY) cells in the arcuate nucleus, all of which are involved in feeding-fasting cycles, energy homeostasis and sending projections to the LH. The results indicate that feeding during the rest phase decreased orexin neuron activation in the light in comparison with the other groups. Feeding during this phase also flattened the activity rhythm of MCH and α-melanin-stimulating hormone neurons and increased NPY IR when the light was turned on. This evidence indicates that mealtime differentially affected the hypothalamic nuclei under investigation leading to a circadian conflict that might account for metabolic impairment.


Assuntos
Ciclos de Atividade , Ritmo Circadiano , Metabolismo Energético , Comportamento Alimentar , Hipotálamo/fisiologia , Animais , Ingestão de Alimentos , Homeostase , Hormônios Hipotalâmicos/metabolismo , Hipotálamo/citologia , Hipotálamo/metabolismo , Masculino , Melaninas/metabolismo , Neurônios/metabolismo , Neurônios/fisiologia , Neuropeptídeo Y/metabolismo , Orexinas/metabolismo , Hormônios Hipofisários/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Wistar , Sono
3.
J Neurosci ; 35(46): 15419-29, 2015 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-26586828

RESUMO

In mammals, daily changes in body temperature (Tb) depend on the integrity of the suprachiasmatic nucleus (SCN). Fasting influences the Tb in the resting period and the presence of the SCN is essential for this process. However, the origin of this circadian/metabolic influence is unknown. We hypothesized that, not only the SCN but also the arcuate nucleus (ARC), are involved in the Tb setting through afferents to the thermoregulatory median preoptic nucleus (MnPO). Therefore, we investigated by neuronal tracing and microdialysis experiments the possible targeting of the MnPO by the SCN and the ARC in male Wistar rats. We observed that vasopressin release from the SCN decreases the temperature just before light onset, whereas α-melanocyte stimulating hormone release, especially at the end of the dark period, maintains high temperature. Both peptides have opposite effects on the brown adipose tissue activity through thermoregulatory nuclei such as the dorsomedial nucleus of the hypothalamus and the dorsal raphe nucleus. The present study indicates that the coordination between circadian and metabolic signaling within the hypothalamus is essential for an adequate temperature control. SIGNIFICANCE STATEMENT: When circadian and metabolic systems are not well synchronized, individuals may develop metabolic diseases. The underlying mechanisms are unknown. Here, we demonstrate that the balance between the releases of neuropeptides derived from the biological clock and from a metabolic sensory organ as the arcuate nucleus, are essential for an adequate temperature control. These observations show that brain areas involved in circadian and metabolic functions of the body need to interact to produce a coherent arrangement of physiological processes associated with temperature control.


Assuntos
Núcleo Arqueado do Hipotálamo/fisiologia , Ritmo Circadiano/fisiologia , Núcleo Supraquiasmático/fisiologia , Temperatura , Animais , Antagonistas dos Receptores de Hormônios Antidiuréticos/farmacologia , Núcleo Arqueado do Hipotálamo/citologia , Arginina Vasopressina/análogos & derivados , Arginina Vasopressina/metabolismo , Arginina Vasopressina/farmacologia , Toxina da Cólera/farmacocinética , Glutamato Descarboxilase/metabolismo , Hormônios Estimuladores de Melanócitos/farmacologia , Microdiálise , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neuropeptídeos/farmacologia , Estimulação Luminosa , Área Pré-Óptica/efeitos dos fármacos , Área Pré-Óptica/fisiologia , Proteínas Proto-Oncogênicas c-fos , Ratos , Núcleo Supraquiasmático/citologia , alfa-MSH/análogos & derivados , alfa-MSH/metabolismo , alfa-MSH/farmacologia
4.
Res Sq ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39041039

RESUMO

The secretion of cortisol in humans and corticosterone (Cort) in rodents follows a daily rhythm which is important in readying the individual for the daily active cycle and is impaired in chronic depression. This rhythm is orchestrated by the suprachiasmatic nucleus (SCN) which governs the activity of neurons in the paraventricular nucleus of the hypothalamus that produce the corticotropin-releasing hormone (PVHCRH neurons). The dorsomedial nucleus of the hypothalamus (DMH) serves as a crucial intermediary, being innervated by the SCN both directly and via relays in the subparaventricular zone, and projecting axons to the PVH, thereby exerting influence over the cortisol/corticosterone rhythm. However, the role and synaptic mechanisms by which DMH neurons regulate the daily rhythm of Cort secretion has not been explored. We found that either ablating or acutely inhibiting the DMH glutamatergic (DMHVglut2) neurons resulted in a 40-70% reduction in the daily peak of Cort. Deletion of the Vglut2 gene within the DMH produced a similar effect, highlighting the indispensable role of glutamatergic signaling. Chemogenetic stimulation of DMHVglut2 neurons led to an increase of Cort levels, and optogenetic activation of their terminals in the PVH in hypothalamic slices directly activated PVHCRH neurons through glutamate release (the DMHVglut2 → PVHCRH pathway). Similarly, ablating, inhibiting, or disrupting GABA transmission by DMH GABAergic (DMHVgat) neurons diminished the circadian peak of Cort, particularly under constant darkness conditions. Chemogenetic stimulation of DMHVgat neurons increased Cort, although with a lower magnitude compared to DMHVglut2 neuron stimulation, suggesting a role in disinhibiting PVHCRH neurons. Supporting this hypothesis, we found that rostral DMHVgat neurons project directly to GABAergic neurons in the caudal ventral part of the PVH and adjacent peri-PVH area (cvPVH), which directly inhibit PVHCRH neurons, and that activating the DMHVgat terminals in the cvPVH in brain slices reduced GABAergic afferent input onto the PVHCRH neurons. Finally, ablation of cvPVHVgat neurons resulted in increased Cort release at the onset of the active phase, affirming the pivotal role of the DMHVgat → cvPVHVgat → PVHCRH pathway in Cort secretion. In summary, our study delineates two parallel pathways transmitting temporal information to PVHCRH neurons, collectively orchestrating the daily surge in Cort in anticipation of the active phase. These findings are crucial to understand the neural circuits regulating Cort secretion, shedding light on the mechanisms governing this physiological process and the coordinated interplay between SCN, DMH, and PVH.

5.
Res Sq ; 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37205518

RESUMO

Many species use a temporary drop in body temperature and metabolic rate (torpor) as a strategy to survive food scarcity. A similar profound hypothermia is observed with activation of preoptic neurons that express the neuropeptides Pituitary Adenylate-Cyclase-Activating Polypeptide (PACAP)1, Brain Derived Neurotrophic Factor (BDNF)2, or Pyroglutamylated RFamide Peptide (QRFP)3, the vesicular glutamate transporter, Vglut24,5 or the leptin receptor6 (LepR), estrogen 1 receptor (Esr1)7 or prostaglandin E receptor 3 (EP3R) in mice8. However, most of these genetic markers are found on multiple populations of preoptic neurons and only partially overlap with one another. We report here that expression of the EP3R marks a unique population of median preoptic (MnPO) neurons that are required both for lipopolysaccharide (LPS)-induced fever9 and for torpor. These MnPOEP3R neurons produce persistent fever responses when inhibited and prolonged hypothermic responses when activated either chemo- or opto-genetically even for brief periods of time. The mechanism for these prolonged responses appears to involve increases in intracellular calcium in individual EP3R-expressing preoptic neurons that persist for many minutes up to hours beyond the termination of a brief stimulus. These properties endow MnPOEP3R neurons with the ability to act as a two-way master switch for thermoregulation.

6.
Neurogastroenterol Motil ; 35(12): e14687, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37815021

RESUMO

BACKGROUND: Disrupted circadian rhythms may result from a misalignment between the environmental cycles (due to shift work, sleep restriction, feeding at an unusual time of day) and endogenous rhythms or by physiological aging. Among the numerous adverse effects, disrupted rhythms affect the brain-gut axis, contributing to the pathogenesis of several diseases in the gastrointestinal tract, for example, abdominal pain, constipation, gastric dyspepsia, inflammatory bowel disease, irritable bowel syndrome, and others. METHODS: This study evaluated the rat gastric emptying, gastrointestinal motility, a clock gene, gut hormones, and the neuron activity on the nucleus of tractus solitarius (NTS), area postrema (AP), and the dorsal motor nucleus of the vagus (DMV) in rats with restricted food access to the rest phase for 4 weeks. KEY RESULTS: Our results show that food restricted to the rest light period disturbed the expression pattern of a series of transcripts, including metabolic and circadian regulation. Also, the secretion of gastrointestinal hormones, gastric emptying, intestinal motility, and NTS, AP, and DMV activity were altered. CONCLUSIONS & INFERENCES: These data indicate the importance of the time of the day food is ingested on the regulation of energy balance and the endocrine activity of the stomach and small intestine, emphasizing the importance of food as a powerful circadian synchronizer and an essential factor for the triggering of gastrointestinal diseases and metabolic problems. These findings offer a novel clue regarding the obesity-promoting effect attributed to feeding time and open the possibility of treating this and other intestinal disorders.


Assuntos
Gastroenteropatias , Hormônios Gastrointestinais , Ratos , Animais , Estômago , Nervo Vago/fisiologia , Ritmo Circadiano/fisiologia , Hormônios Gastrointestinais/fisiologia , Neurônios , Gastroenteropatias/metabolismo
7.
Exp Biol Med (Maywood) ; 248(23): 2381-2392, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38143435

RESUMO

Disturbance of sleep homeostasis encompasses health issues, including metabolic disorders like obesity, diabetes, and augmented stress vulnerability. Sleep and stress interact bidirectionally to influence the central nervous system and metabolism. Murine models demonstrate that decreased sleep time is associated with an increased systemic stress response, characterized by endocrinal imbalance, including the elevated activity of hypothalamic-pituitary-adrenal axis, augmented insulin, and reduced adiponectin, affecting peripheral organs physiology, mainly the white adipose tissue (WAT). Within peripheral organs, a local stress response can also be activated by promoting the formation of corticosterone. This local amplifying glucocorticoid signaling is favored through the activation of the enzyme 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1). In WAT, 11ß-HSD1 activity is upregulated by the sympathetic nervous system, suggesting a link between sleep loss, augmented stress response, and a potential WAT metabolic disturbance. To gain more understanding about this relationship, metabolic and stress responses of WAT-sympathectomized rats were analyzed to identify the contribution of the autonomic nervous system to stress response-related metabolic disorders during chronic sleep restriction. Male Wistar rats under sleep restriction were allowed just 6 h of daily sleep over eight weeks. Results showed that rats under sleep restriction presented higher serum corticosterone, increased adipose tissue 11ß-HSD1 activity, weight loss, decreased visceral fat, augmented adiponectin, lower leptin levels, glucose tolerance impairment, and mildly decreased daily body temperature. In contrast, sympathectomized rats under sleep restriction exhibited decreased stress response (lower serum corticosterone and 11ß-HSD1 activity). In addition, they maintained weight loss, explained by a reduced visceral fat pad, leptin, and adiponectin, improved glucose management, and persisting decline in body temperature. These results suggest autonomic nervous system is partially responsible for the WAT-exacerbated stress response and its metabolic and physiological disturbances.


Assuntos
Corticosterona , Doenças Metabólicas , Masculino , Camundongos , Ratos , Animais , Corticosterona/metabolismo , Leptina/metabolismo , Gordura Intra-Abdominal/metabolismo , Adiponectina/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Ratos Wistar , Sistema Hipófise-Suprarrenal/metabolismo , Tecido Adiposo/metabolismo , Redução de Peso , Sono , Doenças Metabólicas/metabolismo , Simpatectomia , Glucose/metabolismo
8.
Chronobiol Int ; 39(3): 374-385, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34906015

RESUMO

Temporal coordination of organisms according to the daytime allows a better performance of physiological processes. However, modern lifestyle habits, such as food intake during the rest phase, promote internal desynchronization and compromise homeostasis and health. The hypothalamic suprachiasmatic nucleus (SCN) synchronizes body physiology and behavior with the environmental light-dark cycle by transmitting time information to several integrative hypothalamic nuclei, such as the paraventricular nucleus (PVN), dorsomedial hypothalamic nucleus (DMH) and median preoptic area (MnPO). The SCN receives metabolic information mainly via Neuropeptide Y (NPY) inputs from the intergeniculate nucleus of the thalamus (IGL). Nowadays, there is no evidence of the response of the PVN, DMH and MnPO when the animals are subjected to internal desynchronization by restricting food access to the rest phase of the day. To explore this issue, we compared the circadian activity of the SCN, PVN, DMH and MnPO. In addition, we analyzed the daily activity of the satiety centers of the brainstem, the nucleus of the tractus solitarius (NTS) and area postrema (AP), which send metabolic information to the SCN, directly or via the thalamic intergeniculate leaflet (IGL). For that, male Wistar rats were assigned to three meal protocols: fed during the rest phase (Day Fed); fed during the active phase (Night Fed); free access to food (ad libitum). After 21 d, the daily activity patterns of these nuclei were analyzed by c-Fos immunohistochemistry, as well as NPY immunohistochemistry, in the SCN. The results show that eating during the rest period produces a phase advance in the activity of the SCN, changes the daily activity pattern in the MnPO, NTS and AP and flattens the c-Fos rhythm in the PVN and DMH. Altogether, these results validate previous observations of circadian dysregulation that occurs within the central nervous system when meals are consumed during the rest phase, a behavior that is involved in the metabolic alterations described in the literature.


Assuntos
Ritmo Circadiano , Hipotálamo , Animais , Masculino , Ratos , Ritmo Circadiano/fisiologia , Hipotálamo/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos Wistar , Núcleo Supraquiasmático/metabolismo
9.
Front Neurosci ; 16: 907508, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937866

RESUMO

Epidemiological and experimental evidence recognize a relationship between sleep-wake cycles and adiposity levels, but the mechanisms that link both are not entirely understood. Adipose tissue secretes adiponectin and leptin hormones, mainly involved as indicators of adiposity levels and recently associated to sleep. To understand how two of the main adipose tissue hormones could influence sleep-wake regulation, we evaluated in male rats, the effect of direct administration of adiponectin or leptin in the ventrolateral preoptic nuclei (VLPO), a major area for sleep promotion. The presence of adiponectin (AdipoR1 and AdipoR2) and leptin receptors in VLPO were confirmed by immunohistochemistry. Adiponectin administration increased wakefulness during the rest phase, reduced delta power, and activated wake-promoting neurons, such as the locus coeruleus (LC), tuberomammillary nucleus (TMN) and hypocretin/orexin neurons (OX) within the lateral hypothalamus (LH) and perifornical area (PeF). Conversely, leptin promoted REM and NREM sleep, including increase of delta power during NREM sleep, and induced c-Fos expression in VLPO and melanin concentrating hormone expressing neurons (MCH). In addition, a reduction in wake-promoting neurons activity was found in the TMN, lateral hypothalamus (LH) and perifornical area (PeF), including in the OX neurons. Moreover, leptin administration reduced tyrosine hydroxylase (TH) immunoreactivity in the LC. Our data suggest that adiponectin and leptin act as hormonal mediators between the status of body energy and the regulation of the sleep-wake cycle.

10.
Rev. panam. salud pública ; 47: e156, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1530309

RESUMO

ABSTRACT Objective. To highlight the objectives, achievements, challenges, and next steps for the World Health Organization's Global Initiative for Childhood Cancer (GICC) framework, a project designed to improve psychosocial care (PSC) in pediatric cancer centers across Latin America and the Caribbean (LAC). Methods. The project was launched in Peru, the first GICC focal country, in November 2020. The diagnosis phase included a survey and a semistructured interview with health professionals to assess PSC practices in institutions, and a needs assessment survey for caregivers. In the second phase, a strategic plan was developed to address the identified needs, including the adaptation of PSC standards, the establishment of multicenter working groups, the expansion of the proposal, and the development of materials. Results. The study found that PSC was not being adequately provided in accordance with international standards. Six adapted standards were proposed and validated, and more than 50 regional health professionals participated in online activities to support the project. The implementation process is currently ongoing, with the establishment of five multidisciplinary working groups, one regional committee, and the production of 16 technical outputs. Conclusion. This project represents a substantial step forward to improve PSC for pediatric patients with cancer and their families in LAC countries. The establishment of working groups and evidence-based interventions strengthen the proposal and its implementation. Development of health policies that include PSC according to standards is needed to achieve sustainable results in the quality of life of children with cancer and their families.


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RESUMO Objetivo. Destacar os objetivos, as conquistas, os desafios e as próximas etapas da Iniciativa Global para o Câncer Infantil (GICC), um projeto criado pela Organização Mundial da Saúde para melhorar a atenção psicossocial em centros de câncer pediátrico na América Latina e no Caribe. Métodos. O projeto foi lançado no Peru, o primeiro país focal da GICC, em novembro de 2020. A fase de diagnóstico incluiu uma pesquisa e uma entrevista semiestruturada com profissionais de saúde para avaliar as práticas de atenção psicossocial nas instituições, bem como uma pesquisa para avaliar as necessidades dos cuidadores. Na segunda fase, foi desenvolvido um plano estratégico para atender às necessidades identificadas, incluindo uma adaptação de padrões de atenção psicossocial, o estabelecimento de grupos de trabalho multicêntricos, a expansão da proposta e o desenvolvimento de materiais. Resultados. O estudo constatou que, de acordo com padrões internacionais, a atenção psicossocial não estava sendo adequadamente oferecida. Seis padrões adaptados foram propostos e validados, e mais de 50 profissionais de saúde da região participaram de atividades on-line para apoiar o projeto. O processo de implementação está em andamento, com a formação de cinco grupos de trabalho multidisciplinares e um comitê regional e a produção de 16 relatórios técnicos. Conclusão. Este projeto representa um avanço substancial para melhorar a atenção psicossocial para pacientes pediátricos com câncer e suas famílias nos países da América Latina e do Caribe. A criação de grupos de trabalho e intervenções baseadas em evidências fortalecem a proposta e sua implementação. É preciso desenvolver políticas de saúde que incluam atenção psicossocial segundo padrões estabelecidos para alcançar resultados sustentáveis na qualidade de vida das crianças com câncer e de suas famílias.

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