Chronotype in bipolar disorder: Differences in sleep quality, social jet lag, physical activity, and diet / Cronotipo en trastorno bipolar: Diferencias en la calidad de sueño, jet lag social, actividad física y dieta

Abstract Introduction People with bipolar disorder are at a higher risk of metabolic morbidity and mortality. Chronotype may play a significant role due to its effect on sleep quality, eating patterns, and physical activity. Objective To compare sleep quality, social jetlag, physical activity, and diet, depending on the chronotype of people with bipolar disorder, and to determine the association between these variables. Method Cross-sectional, comparative, correlational study. The sociodemographic and clinical characteristics of subjects were assessed. Chronotype was determined using the Composite Scale of Morningness while sleep quality was evaluated through the Pittsburg Sleep Quality Index. Social jet lag was calculated through the absolute difference between the midpoint of sleep on weekends and workdays. Physical activity was measured through the Bouchard Activity Record and diet was evaluated through a food frequency questionnaire. Comparative analyses were performed between chronotype categories and the association between variables was measured. Results 116 subjects were included. Subjects with evening chronotype reported poorer sleep quality than those with morning chronotype. Eveningness was associated with lower sleep quality scores and more hours of sleep on workdays, as well as with higher consumption of cold meats, calories, and sodium. Trends indicate greater social jet lag and low physical activity levels among evening chronotypes. Discussion and conclusion The effects of chronotype on study variables require further research to clarify this complex relationship and develop educational strategies to promote sleep hygiene, physical activity, and a healthy diet.

Resumen Introducción Las personas con trastorno bipolar corren mayor riesgo de presentar morbimortalidad metabólica. El cronotipo podría desempeñar un rol importante por su efecto sobre la calidad de sueño, los patrones de alimentación y la actividad física. Objetivo Comparar la calidad de sueño, el jet lag social, la actividad física y la dieta en función del cronotipo de personas con trastorno bipolar, así como determinar la asociación entre estas variables. Método Estudio transversal, comparativo y correlacional. Se evaluaron las características sociodemográficas y los antecedentes clínicos de los participantes. El cronotipo se determinó con la Escala Compuesta de Matutinidad y la calidad de sueño con el Índice de Calidad de Sueño Pittsburg. El jet lag social se calculó como la diferencia absoluta entre el punto medio de sueño en días libres y de trabajo. La actividad física se midió con el registro de Bouchard y la dieta con un cuestionario de frecuencia de consumo de alimentos. Se realizaron análisis comparativos entre categorías de cronotipo y se evaluó la asociación entre variables. Resultados Se incluyeron 116 participantes. Las personas de cronotipo vespertino reportaron menor calidad de sueño en comparación con las del cronotipo matutino. La vespertinidad se asoció a puntuaciones de menor calidad de sueño y más horas para dormir en días de trabajo, así como a mayor consumo de embutidos, calorías y sodio. Las tendencias indican mayor jet lag social y bajo nivel de actividad física entre cronotipos vespertinos. Discusión y conclusión Los efectos del cronotipo sobre las variables de estudio requieren más investigación, que aclare esta compleja relación, para desarrollar estrategias educativas de higiene de sueño, actividad física y dieta saludable.

At the crossroads of epilepsy and sleep: some issues / Na encruzilhada da epilepsia e do sono: algumas questões

There is a close association between sleep and epilepsy, and this literature review aims to raise issues regarding sleep time control, circadian and ultradian rhythms, epilepsy and its interaction with sleep and circadian rhythm, epilepsy and sleep disorders, and finally epilepsy management and medications. It is mentioned that sleep may provide a hypersynchronous state, as occurs in non-rapid eye movement sleep (NREM), and hyperexcitability, in cyclic alternating pattern (CAP), allowing more frequent interictal epileptiform abnormalities and seizures. In some epilepsy syndromes, seizures occur broadly / or entirely during sleep or on awakening, mainly in childhood, and maybe exacerbated in adults during the sleep or sleep-deprived, and there are the so-called Sleep-related epilepsies that are divided as sleep-associated, sleep-accentuated and arousal/awakening related. Sleep quality may be reduced in patients with epilepsy also due to nocturnal seizures or concomitant sleep disorders. Sleep disorders are common in patients with epilepsy and treatment of them mainly sleep-disordered breathing may improve seizure control. Besides, some parasomnias may mimic seizures, and also they can adversely affect the quality and quantity of sleep whereas antiepileptic therapy can have a negative or positive effect on sleep. Nocturnal epileptic seizures may be challenging to discern from parasomnias, in particular NREM parasomnias such as night terrors, sleepwalking and confusional arousals.

Há uma estreita associação entre sono e epilepsia, e esta revisão de literatura tem como objetivo levantar questões relacionadas ao controle do tempo do sono, ritmos circadianos e ultradianos, epilepsia e sua interação com sono e ritmo circadiano, epilepsia e transtornos do sono e, finalmente, o tratamento e medicamentos para epilepsia. Menciona-se que o sono pode proporcionar um estado hipersincrônico, como ocorre no sono "non-rapid eye movement" (NREM), e hiperexcitabilidade, no "cyclic alternating pattern" (CAP), permitindo anormalidades epileptiformes interictais e crises epilépticas mais frequentes. Em algumas síndromes epilépticas, as crises ocorrem ampla / ou inteiramente durante o sono ou despertar, principalmente na infância, e podem ser exacerbadas em adultos durante o sono ou privação de sono, e as chamadas epilepsias relacionadas ao sono se dividem em sono associadas, sono acentuadas e relacionadas com o despertar. A qualidade do sono pode ser reduzida em pacientes com epilepsia também devido a crises epilépticas noturnas ou transtornos do sono concomitantes. Esses são comuns em pacientes com epilepsia e o seu tratamento, principalmente dos transtornos respiratórios do sono, pode melhorar o controle das crises epilépticas. Além disso, algumas parassonias podem mimetizar crises epilépticas, e também elas podem afetar adversamente a qualidade e a quantidade do sono, enquanto a terapia antiepiléptica pode ter um efeito negativo ou positivo sobre o sono. Pode ser difícil discernir as crises epilépticas noturnas das parassonias, em particular das parassonias NREM, como terrores noturnos, crises de sonambulismo e despertares confusionais.

Pacientes ingresados por recaída aguda de esquizofrenia paranoide: cambios estacionales, pero no circadianos, en los niveles séricos deproteína S100B / Patients admitted for acute relapse of paranoid schizophrenia: seasonal, but not circadian, changes in serum levels of S100B protein

Introducción: El objetivo de esta investigación es estudiar si los pacientes esquizofrénicos presentan niveles másaltos de proteína S100B en verano que en invierno, como seha descrito en sujetos sanos.Método. Se estudiaron 52 pacientes caucásicos que ingresaron por recaída aguda y que cumplían con los criteriosDSM-IV de esquizofrenia paranoide. La proteína S100B ensuero se midió a las 12:00 y las 00:00 horas el día despuésdel ingreso. Los pacientes fueron reclutados durante nuevemeses (julio-marzo) y se agruparon por estación, según lafecha de ingreso, como grupo de verano, otoño o invierno.Los niveles séricos de S100B se midieron con un ELISA.Resultados. Los pacientes ingresados en invierno presentaron niveles séricos de proteína S100B significativamentemás altos a las 12:00 y 00:00 horas que los pacientes ingresados en verano (12:00, invierno: 287,5 ± 264,9 vs. verano: 33,7 ± 22,6, p < 0,05; 00:00, invierno: 171,2 ± 143,8 vs.verano: 23,3 ± 18,6, p < 0,05). Las concentraciones séricasde S100B en otoño no fueron significativamente diferentesde las concentraciones de verano o invierno (12:00: 128,7 ±208,8, 00:00: 102,2 ± 153,2). No hubo diferencias significativas por estación entre las concentraciones diurnas y nocturnas de proteína S100B.Conclusiones. Los pacientes esquizofrénicos hospitalizados por una descompensación aguda presentan concentraciones séricas de proteína S100B significativamente másaltas en invierno que en verano, al contrario de lo descritoen sujetos sanos, tanto a las 12:00 horas como a las 00:00horas. Al estudiar este biomarcador en la esquizofrenia esrecomendable controlar el cambio de estación como fuentede sesgo en los diseños experimentales. (AU)

Introduction: Healthy subjects present higher summerthan winter S100B protein concentrations. There is no available information regarding if schizophrenia patients presentthe same pattern. The aim of this research is to study if patients with schizophrenia present seasonal changes in serumS100B concentrations.Methods. In fifty-two Caucasian schizophrenia paranoidinpatients meeting DSM-IV criteria, serum S100B protein wasmeasured at 12:00 h and 00:00 h the next day after admission.Patients were recruited for a period of nine months (July-March)and were grouped as summer, autumn or winter group according to the date of admission. Serum S100B levels were measuredwith an enzyme-linked immunoassay (ELISA) kit.Results. Patients admitted in winter had significantly higher serum S100B concentrations at 12:00 h and 00:00 h than patients admitted in summer (12:00, winter: 287.5±264.9 vs.summer: 33.7±22.6, p < 0.05; 00:00, winter: 171.2±143.8 vs.summer: 23.3±18.6, p < 0.05). Autumn serum S100B concentrations were not significantly different from the summer or winter concentrations (12:00: 128.7±208.8, 00:00:102.2±153.2). There were no significant differences between12:00 and 00:00 serum S100B concentrations in any season.Conclusions. Acutely relapsed paranoid schizophreniainpatients present significantly higher serum S100B concentrations in winter than summer, the opposite pattern described in healthy subjects, both at midday and midnight.Controlling this seasonal change as source of bias in experimental designs is strongly advisable. (AU)

[Positive effect of bright light therapy on mood and sleep quality in institutionalized older people]. / Efecto positivo de la terapia de luz brillante sobre el estado de ánimo y la calidad del sueño en las personas mayores institucionalizadas.

INTRODUCTION: Bright light exposure during the day has a positive effect on health and its deficit can cause multiple physiological and cognitive disorders, including depression. The aim of this study was to evaluate the effect of bright light therapy (BLT) on the quality of sleep and mood emotional state; cognitive status, global deterioration and quality of life in institutionalized elderly. MATERIAL AND METHODS: This is a study with repeated measures design. Thirty-seven older people admitted to a nursing home. The study lasted 3 weeks. The first week, the reference values were established with the Oviedo Sleep Questionnaire, Yesavage Depression Scale, Mini-Mental, Global Scale of Impairment and European Quality of Life Questionnaire. During the second week, they were exposed to BLT (7,000-10,000lx at eye level) between 9:30 a.m. and 11:00 a.m. During the third week, all the data were re-evaluated. RESULTS: All variables improved significantly after the application of light therapy. Sleep (COS) pre-test 4.1±1.49, post-test 4.9±1.46, p: 0.01), mood (pre-test 3.65±2.78, post-test 2.65±2.9, p: 0.01), cognitive state (pre-test 22.72±6.53, post-test 24±5.92, p: 0.001), state of global deterioration (pre-test 3.10±1.26, post-test 2.72±5.92, p: 0.001) and health-related quality of life (pre-test 6.93±1.86, post-test 7.82±1.62, p: 0.001). CONCLUSIONS: Sleep quality, mood, cognitive status, global deterioration status and quality of life significantly improved after the application of light bright therapy.

The role of circadian rhythms in individuals with attention deficit hyperactivity disorder and obesity: A narrative review / El papel de los ritmos circadianos en personas con trastorno por déficit de atención con hiperactividad y obesidad: Una revisión narrativa

Abstract Background A relationship between attention deficit hyperactivity disorder (ADHD) and obesity has been consistently documented. Obesity and metabolic syndrome have been associated with misalignment between daily activities and circadian rhythm. ADHD patients have a high prevalence of delayed sleep phase syndrome, which is a circadian rhythm disorder. Understanding this relationship is important for the evaluation of obese population at risk. Objective The aim of this narrative review was to summarize the information updated until 2019 about the role of circadian rhythms in obese ADHD individuals. Method A search was performed in MEDLINE, EMBASE, and Google Scholar database. The terms ADHD, obesity, circadian rhythm, sleep disorders, adolescent, adult, Adolesc, circadian, attention deficit hyperactivity disorder, and child were combined with logical functions. Results A total of 132 articles were reviewed. Evidence showed that ADHD subjects have an increased risk to present obesity and circadian rhythms disorders. Some possible pathways for this relationship have been hypothesized including obesity as a risk factor, an underpinned common biological dysfunction, and behavioral and cognitive features of individuals with ADHD. As most of the articles are methodologically cross-sectional, it is not possible to establish causative associations. Discussion and conclusion This review points out the importance of early recognizing and treating circadian rhythms disorders and obesity in ADHD patients. Future studies must be carried out with a longitudinal design to establish the effect of each comorbidity in the treatment of individuals with ADHD.

Resumen Antecedentes La relación entre el trastorno por déficit de atención con hiperactividad (TDAH) y la obesidad se ha documentado consistentemente. Por otro lado, el síndrome metabólico y la obesidad se han asociado con un desfase del ritmo circadiano. En poblaciones clínicas con TDAH se han encontrado una alta prevalencia del trastorno de fase de sueño retrasada, el cual es un trastorno del ritmo circadiano. Entender la relación entre estos padecimientos es importante para evaluar la población en riesgo de obesidad. Objetivo Resumir la información actualizada hasta 2019 sobre el rol del ritmo circadiano en individuos obesos con TDAH. Método Se realizó una búsqueda de artículos en las bases de datos MEDLINE, EMBASE y Google Scholar. Los términos TDAH, obesidad, ritmos circadianos, trastornos del sueño, adolescentes, adultos y niños se combinaron con operadores lógicos. Resultados Se revisaron un total de 132 artículos. La evidencia demostró que los sujetos con TDAH tienen un alto riesgo de sufrir obesidad y ritmos circadianos alterados. Existen algunas hipótesis para establecer esta relación, incluyendo la obesidad como factor de riesgo para TDAH, la disfunción biológica común entre estos trastornos y las características conductuales y cognitivas de los individuos con TDAH. Sin embargo, como la mayoría de los artículos son transversales, no es posible establecer una asociación causal. Discusión y conclusión Esta revisión señala la importancia del reconocimiento temprano y tratamiento de los trastornos del ritmo circadiano y obesidad en pacientes con TDAH. Estudios futuros deben realizarse de manera longitudinal para establecer el efecto de estas comorbilidades en el tratamiento de los individuos con TDAH.

Causas y efectos en la falta de sueño en niños hospitalizados / Causes and effects of lack of sleep in hospitalized children

El sueño es una función vital en la que transcurre un tercio de nuestras vidas. Su restricción puede provocar trastornos físicos y psíquicos a corto y largo plazo.La internación hospitalaria, sin tener en cuenta la enfermedad que la originó, no favorece un sueño reparador y suficiente. Los factores que interfieren son externos (luz, ruidos) e internos (procedimientos, fármacos, cuidados).La Unidad de Cuidados Intensivos es el lugar con mayor dificultad para la conciliación y el mantenimiento del sueño. Se suma la gravedad de la enfermedad y las características de su estructura y funcionamiento.El deterioro de la cantidad o calidad del sueño podría desencadenar un cuadro de confusión mental agudo que, con frecuencia, afecta a los niños internados, reconocido como delirium. Promover, en el medio institucional, un trabajo conjunto de todos los estamentos para proteger el sueño dentro de lo posible es una tarea por realizar.

Sleep is a key function that takes up one third of our lives. Sleep deprivation may lead to physical and psychological disorders in the short and long term.Hospitalization, regardless of its cause, does not favor good enough and restorative sleep. It is affected by both external (light, noise) and internal (procedures, drugs, care) factors.The intensive care unit is the place where falling asleep and maintaining sleep is more difficult. This is in addition to disease severity and the characteristics of its structure and functioning.A poor sleep quantity or quality may trigger an acute confusional state, which often affects hospitalized children, known as delirium. Promoting a joint effort among all sectors of the hospital setting targeted at protecting sleep as much as possible is the required task.

Síndrome de jet lag o cambio de zonas de tiempo / The jet lag syndrome or time-zone changes

Resumen Nuestro planeta, así como la vida que en él se desarrolla, se encuentra en constante movimiento. Los ritmos geofísicos influyen en la actividad de los organismos, de tal manera que los seres vivos han desarrollado mecanismos adaptativos para poder responder a las variaciones diarias del medio ambiente. El sistema circadiano es el responsable de responder a estas variaciones cíclicas ambientales. Cuando se modifican las señales ambientales, como en un viaje que implica atravesar varias zonas horarias, se ocasionan cambios fisiológicos que han llevado a buscar estrategias para contrarrestar los síntomas que se presentan; estas estrategias incluyen el ejercicio programado, la exposición a la luz brillante, la melatonina y la alimentación programada.

Abstract Our planet and the life that develops in it are in constant movement, therefore, the geophysical rhythms influence the activity of organisms, in such a way that living beings have developed adaptative mechanims in order to respond to the daily variations of the environment. The circadian system is responsible for responding to these cyclical environmental variations. When the environmental signals are modified, like for instance, on a trip that involves crossing several time zones, physiological changes occur. This results in searching for possible strategies to counteract the symptomatology. These strategies include scheduled exercise, exposure to a bright light, melatonin and scheduled meals.

Regulación circadiana, patrón horario de alimentación y sueño: Enfoque en el problema de obesidad / Circadian rhythms, eating patterns, and sleep: A focus on obesity

RESUMEN El reloj biológico determina la mantención de los ritmos circadianos en mamíferos, un tipo particular de ritmos biológicos de duración cercana a 24 horas. Existe una estrecha relación entre el funcionamiento del sistema circadiano, la alimentación y la regulación metabólica, lo que actualmente constituye un área de intensa investigación. En particular, la alteración de la ritmicidad circadiana a partir de modificaciones genéticas, conductuales o dietarias, lleva a trastornos comportamentales, ganancia de peso excesiva y alteraciones metabólicas. Algunos factores que contribuyen a la alteración o desajuste circadiano incluyen el jet-lag, el trabajo por turnos horarios, la desorganización temporal y restricción de sueño, y desorden del patrón horario de alimentación. Este trabajo resume la evidencia acerca de la influencia de los ritmos circadianos en procesos relacionados con la alimentación y las consecuencias metabólicas de su alteración. Se hace énfasis en las consecuencias de la alteración de los ritmos de alimentación-ayuno y de sueño-vigilia, y su relación con la ganancia de peso excesiva, la obesidad y trastornos metabólicos asociados, condiciones altamente prevalentes en sociedades occidentalizadas.

ABSTRACT In mammals, the biological clock is driven by circadian rhythms, a particular type of biological rhythm that last about 24 hours. There is a close relationship between the functioning of the circadian system, eating and metabolic regulation, which is currently an area of intense research. Alteration of circadian rhythmicity from genetic, behavioral or dietary modifications, leads to behavioral and metabolic disorders, and excessive weight gain. Factors that contribute to circadian disruption include, among others, jet lag, shift work, mistimed and restricted sleep, and irregular eating patterns. This review summarizes the evidence regarding the influence of circadian rhythms on eating processes and the metabolic consequences of circadian disruption. Special focus is on the consequences of disruption of regular eating-fasting and sleep-wake rhythms, and relationships with excessive weight gain, obesity and obesity-related metabolic disorders that are highly prevalent in westernized societies.

Activity/rest rhythm of depressed adolescents undergoing therapy: case studies / Ritmo de atividade e repouso em adolescentes deprimidos durante terapia: estudos de caso

Abstract Introduction: Disorders of circadian rhythms have been reported in studies of both depressed children and of depressed adolescents. The aim of this study was to evaluate whether there is a relationship between the 24-hour spectral power (24h SP) of the activity/rest rhythm and the clinical course of depression in adolescents. Methods: Six 14 to 17-year-old adolescents were recruited for the study. They were all suffering from major depressive disorder, according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) criteria, as identified by the Schedule for Affective Disorders and Schizophrenia for School Aged Children: Present and Lifetime Version (K-SADS-PL). Depressive symptoms were assessed using the Children's Depression Rating Scale - Revised (CDRS-R) and clinical evaluations. Locomotor activity was monitored over a period of 13 consecutive weeks. Activity was measured for 10-minute periods using wrist-worn activity monitors. All patients were prescribed sertraline from after the first week up until the end of the study. Results: We found a relationship between high CDRS values and low 24-hour spectral power. Conclusions: The 24h SP of the activity/rest rhythm correlated significantly (negatively) with the clinical ratings of depression.

Resumo Introdução: Distúrbios do ritmo circadiano têm sido relatados em estudos com crianças e adolescentes deprimidos. O objetivo deste estudo foi avaliar se existe relação entre a potência espectral de 24 horas do ritmo de atividade e repouso e sintomas clínicos de depressão em adolescentes. Métodos: Seis adolescentes com idade entre 14 e 17 anos foram recrutados para o estudo. Eles foram diagnosticados com depressão maior de acordo com os critérios do Manual Diagnóstico e Estatístico de Transtornos Mentais, 4ª edição (DSM-IV), identificados utilizando-se o instrumento Schedule for Affective Disorders and Schizophrenia for School Aged Children: Present and Lifetime Version (K-SADS-PL). Os sintomas depressivos foram avaliados pelo questionário Children's Depression Rating Scale - Revised (CDRS-R) e por avaliações clínicas. A atividade motora foi monitorada por um período de 13 semanas consecutivas e registrada a cada 10 minutos utilizando-se monitores de atividades usados no pulso. Todos os pacientes utilizaram o antidepressivo sertralina começando após a primeira semana até o final do estudo. Resultados: Foi observada uma relação entre escores altos no CDRS-R e valores baixos de potência espectral de 24 horas no ritmo de atividade e repouso. Conclusão: A potência espectral de 24 horas do ritmo de atividade e repouso apresentou uma correlação significativa (negativa) com os sintomas clínicos de depressão.

Los ritmos circadianos en cáncer y la cronoterapia / The circadian rhythms in cancer and chronotherapy / Os ritmos circadianos em câncer e a cronoterapia

Los ritmos circadianos, períodos fisiológicos de 24 horas aproximadamente, coordinan la actividad temporal de la mayoría, si no, de todos los seres vivos del planeta. Uno de los procesos más importantes del cuerpo, la proliferación celular, también está regulado por el reloj biológico cuya alteración puede tener repercusiones directas en el desarrollo del cáncer. El concepto de cronoterapia ha surgido a partir de la evidencia que tanto la proliferación de las células, como los mecanismos responsables de la farmacocinética y la farmacodinamia de los antineoplásicos ocurren a horas específicas del día. En esta revisión se presentan las generalidades del ciclo circadiano y su relación con el ciclo celular y el cáncer. Además, se expone evidencia del uso de la cronoterapia en pacientes con leucemia linfocítica aguda y en estudios clínicos de cáncer de colon, endometrio y ovario con asignación aleatoria. Se concluye que la hora de administración de la quimioterapia debe tener en cuenta los ritmos circadianos de los pacientes. Se enfatiza en la necesidad de hacer estudios clínicos enfocados en la quimioterapia cronomodulada, con el fin de aumentar la tolerancia y efectividad de los medicamentos con los protocolos existentes.

Circadian rhythms, physiological periods of about 24 hours, coordinate the temporal processes of most, or maybe all, living beings on the planet. Cell proliferation, one of the most important events in the body, is also regulated by the biological clock, whose alteration may have a direct impact on cancer development. The concept of chronotherapy comes from evidence showing that both cell proliferation and the mechanisms responsible for pharmacokinetics and pharmacodynamics of antineoplastic drugs occur at specific times of the day. This review presents an overview of the circadian cycle and its relation to cell cycle and cancer. Also, it presents evidence for the use of chronotherapy in patients with acute lymphocytic leukemia and in randomized clinical trials for colon, endometrial and ovarian cancer. As a conclusion, the time of chemotherapy administration should take into account the circadian rhythms of patients. We emphasize on the need to conduct clinical trials focused on chronomodulated chemotherapy, in order to increase the tolerance and effectiveness of drugs under the existing protocols.

Os ritmos circadianos, períodos fisiológicos de 24 horas aproximadamente, coordenam a atividade temporal da maioria, se não, de todos os seres vivos do planeta. Um dos processos mais importantes do corpo, a proliferação celular, também está regulada pelo relógio biológico cuja alteração pode ter repercussões diretas no desenvolvimento do câncer O conceito de cronoterapia há surgido a partir da evidência que tanto a proliferação das células, como os mecanismos responsáveis da farmacocinética e a farmacodinâmica dos antineoplásicos ocorrem a horas específicas do dia. Nesta revisão se apresentam as generalidades do ciclo circadiano e sua relação com o ciclo celular e o câncer. Ademais, se expõe evidência do uso da cronoterapia em pacientes com leucemia linfocítica aguda e em estudos clínicos de câncer de cólon, endométrio e ovário com designação aleatória. Se conclui que na hora de administração da quimioterapia deve ter em conta os ritmos circadianos dos pacientes. Se enfatiza na necessidade de fazer estudos clínicos enfocados na quimioterapia cronomodulada, com o fim de aumentar a tolerância e efetividade dos medicamentos com os protocolos existentes.

La comida por la noche como factor inductor de obesidad / Food during the night is a factor leading to obesity

Resumen: Esta revisión tiene como objetivo presentar evidencias obtenidas mediante observaciones clínicas y modelos animales que señalan la relevancia que tiene el horario de alimentación sobre el metabolismo y el mantenimiento del peso corporal. Hallazgos recientes han puesto en evidencia que la misma cantidad de alimento ingerida durante el día o la noche afecta diferencialmente el metabolismo, lo que determina una diferencia significativa en el desarrollo del sobrepeso y la obesidad. Este conocimiento se fundamenta en el estudio del sistema circadiano, regido por el reloj biológico del hipotálamo anterior, que le transmite tiempos a todas las funciones del cuerpo, incluyendo aquellas para el gasto y el ahorro de energía. A pesar de que estos ciclos circadianos están normalmente regulados por los cambios de iluminación resultantes de la alternancia del día y la noche, los cambios metabólicos que resultan de una comida han mostrado también ser señales de tiempo que modifican el orden temporal de algunos sistemas y grupos celulares. De ello se desprende que para que el sistema circadiano funcione sincronizado, las horas de alimentación deben coincidir con los ciclos dictados por el reloj biológico. De tal manera, comer durante las horas normalmente asignadas al reposo lleva a la pérdida de coordinación de los ritmos circadianos metabólicos con respecto al reloj biológico. Esta desincronización sucede a diferentes niveles, tanto entre las células de los tejidos como en una misma célula a nivel molecular. En esta revisión se enfatizarán los efectos adversos de las comidas por la noche sobre el metabolismo energético, además se presentarán resultados recientes que describen los cambios circadianos y metabólicos a diversos niveles de regulación.

Abstract: The present review aims to present evidence obtained in clinical surveys and experimental studies that point out the relevance of meal schedules on metabolism and body weight. Recent findings indicate that in spite of ingesting equivalent amounts, food ingestion during the day or during the night can have completely different effects on metabolism determining bodyweight gain and propensity to obesity. Such findings find support in studies of the circadian rhythms, driven by a biological clock located in the anterior hypothalamus, which transmits temporal signals to the body including functions for energy balance. Circadian cycles are normally driven by the alternation of the day- night luminosity cycles, however metabolic changes resulting from food have proven to be powerful temporal signals capable of modifying de temporal order in tissues and cells. Considering the power of food elicited signals, the feeding schedule must coincide with the timing signals driven by the biological clock. Thus eating during the hours normally assigned for sleep and rest leads to a loss of coordination between metabolic rhythms and the biological clock. This circadian disruption occurs at different levels, among cells in a specific tissue as well as in the molecular processes in cells. The aim of this review is to emphasize the adverse effects that meals during the night can exhert on metabolism, we provide evidence about circadian and metabolic alterations at different regulatory levels.

Ritmos circadianos en pacientes oncológicos / Circadian rhythms in cancer patients

Los ritmos circadianos mantienen la homeostasis del organismo a través de ciclos hormonales, metabólicos y celulares que regulan la proliferación celular. A su vez, estos son mediados por condiciones psicológicas que pueden alterar su funcionamiento y dejar al organismo susceptible a enfermedades como el cáncer. El objetivo de este artículo es revisar la relación de los ritmos circadianos con el cáncer; enfatizando en aquellos ritmos que guardan relación con comportamientos como el ritmo sueño-vigilia y el ritmo circadiano del cortisol. Se busca identificar con esta revisión, posibles repercusiones en la incidencia y pronóstico del cáncer. Así mismo se comentarán los mecanismos psicobiológicos que mantienen la relación entre estos ritmos circa-dianos y cáncer.

Circadian rhythms maintain homeostasis of the body through hormonal, metabolic and cell cycle regulating cell proliferation. In turn, these are mediated by psychological conditions that may affect its operation and leave the body susceptible to diseases like cancer. The aim of this article is to review the relationship of circadian rhythms to cancer; with emphasis on those rhythms that are related to behaviors such as sleep-wake rhythm and the circadian rhythm of cortisol. This review will seek to identify, potential impact on the incidence and prognosis of cancer. Also psychobiological mechanisms that maintain the relationship between the circadian rhythms and cancer will be discussed.

La mala calidad de sueño es factor promotor de obesidad / Poor quality sleep is a contributing factor to obesity

La presente revisión tiene como objetivos presentar a la comunidad académica evidencias recientes que proponen una relación entre la mala calidad y cantidad de sueño y la propensión al sobrepeso y obesidad. Se presentan en este escrito evidencias obtenidas en estudios clínicos controlados y de investigación básica experimental que demuestran que una cantidad o calidad deficiente de sueño lleva a corto plazo a alteraciones de tipo metabólico y conductual conducentes a la sobre ingestión de alimentos y al sobrepeso. También se discuten los posibles mecanismos que pudieran subyacer a este fenómeno, a nivel cerebral, metabólico y celular. El objetivo de esta revisión es presentar a las horas de sueño como un factor poco considerado en los estudios epidemiológicos y experimentales y posible desencadenante de alteraciones metabólicas. Con este escrito esperamos poder interesar a otros profesionistas involucrados en el estudio de este fenómeno para incluir la calidad y cantidad de sueño entre sus variables de estudio y/o incluir la higiene del sueño entre sus propuestas de tratamiento y prevención.

The aim of this revisión is to highlight recent evidence that links low quality and quantity of sleep with an increased propensity to develop overweight or obesity. In this text we present evidence obtained with controlled clinical studies as well as with experimental models, both indicating that decreased hours of sleep lead to metabolic and behavioral changes that then induce overconsumption of food, which then results in weight gain. With this review we want to present sleep as an additional factor contributing to metabolic disease and we aim to raise interest in professional involved in the study of overweight and obesity in order to include this factor as an additional variable in their research and strategies of intervention.

Desarrollo de los ritmos biológicos en el recién nacido. Cátedra Especial "Dr. Ignacio Chávez" / Development of biological rhythms in the newborn child

Los ritmos circadianos se generan de forma endógena con un período de aproximadamente 24 h. Estudios realizados durante la última década indican que el sistema circadiano se desarrolla antes del nacimiento y que el núcleo supraquiasmático, estructura que se considera el reloj circadiano del mamífero, está presente en los primates desde la mitad de la gestación. Evidencias recientes muestran que el sistema circadiano de los infantes es sensible a la luz desde etapas muy tempranas del desarrollo; también se ha propuesto que la iluminación de baja intensidad puede regular el reloj en desarrollo. Después del nacimiento se presenta una maduración progresiva de las salidas del sistema circadiano con marcados ritmos en los fenómenos de sueño-vigilia y secreción de hormonas. Estos hechos expresan la importancia de la regulación fótica circadiana en los lactantes. Así, la exposición de los bebés prematuros a ciclos de luz/oscuridad tiene como resultado un rápido establecimiento de patrones de actividad/reposo, los que se encuentran en el ciclo luz-oscuridad. Con el continuo estudio del desarrollo del sistema circadiano y la influencia sobre la fisiología humana y la enfermedad, se prevé que la aplicación de la biología circadiana se convertirá en un componente cada vez más importante en la atención neonatal.

Circadian rhythms are endogenously generated with a period length of approximately 24 hours. Studies performed during the past decade indicate that the circadian timing system develops prenatally and the suprachias-matic nucleus, considered the site of the circadian clock, is present by midgestation in primates. Recent evidence also shows that the circadian system of primate infants is responsive to light since very early stages of development and that low-intensity lighting can regulate the developing clock. After birth, there is progressive maturation of the circadian system outputs, with pronounced rhythms on sleep-wake phenomena and hormone secretion; showing the importance of photic regulation on infants. Thus, exposure of premature infants to light/dark cycles results in the fast establishment of rest-activity patterns, which are in phase with the light-dark cycle. The continual study of circadian system development and its influence on human physiology and illness, it is foreseen that the application of circadian biology will become increasingly important for neonatal care.

Interrelação entre síndrome metabólica, estresse crônico e ritmos circadianos de marcadores adipogênicos: uma revisão / Interrelation between metabolic syndrome, chronic stress and circadian rhythms of adipogenic markers: a review

Alterações de ritmos circadianos são relacionadas ao desenvolvimento de transtornos metabólicos como obesidade e síndrome metabólica. Além disto, a disponibilidade e o consumo de alimentos altamente palatáveis ricos em gordura e a exposição a situações estressantes podem contribuir na incidência e na severidade destas doenças crônicas, provocando modificações no balanço energético, alterações no metabolismo de lipídeos e adipogênese. Nesta revisão, abordaremos os aspectos cronobiológicos que podem ser influenciados pela exposição a estresse crônico e a obesidade, além dos mecanismos que contribuem para o crescimento de doenças metabólicas (AU)

Alterations in circadian rhythms are associated with the development of metabolic disorders, such as obesity and metabolic syndrome. Moreover, the availability and consumption of highly palatable foods rich in fat and the exposure to stressful situations may contribute to the incidence and severity of these chronic diseases, leading to changes in energy balance, alterations in lipid metabolism and adipogenesis. This review aimed to discuss the chronobiological aspects that can be influenced by the response to chronic stress and obesity, as well as the mechanisms that contribute to the development of metabolic diseases (AU)

Adaptação da escala brian para uso emcrianças e adolescentes: um estudopreliminar / Brian scale adaptation for use in childrenand adolescents: a preliminary study

Introdução: Alterações nos ritmos circadianos tem sido frequentemente observadas entre pacientes com Transtorno do Humor Bipolar (THB). No entanto, existem poucos instrumentos para medi-las e a maioria deles mede exclusivamente distúrbios do sono. A escala BRIAN, validada para adultos com THB, avalia a regularidade dos ritmos biológicos em quatro diferentes aspectos: sono, atividades, social e padrão de alimentação. O objetivo deste estudo-piloto foi adaptar a escala BRIAN para uma população de crianças e adolescentes (BRIAN-K) e avaliar se o novo instrumento é capaz de detectar diferenças entre pacientes e controles saudáveis. Métodos: Foram avaliados 20 pacientes com THB entre 8-16 anos e 32 controles pareados por sexo e idade. Os sujeitos foram avaliados por meio de entrevista clínica, K-SADS-PL e testagem cognitiva. A BRIAN-K foi aplicada em ambos os grupos. Resultados: O grupo de pacientes com THB apresentou escores mais altos de alterações em seus ritmos circadianos pelo escore total da BRIAN-K, quando comparados com o grupo controle (p=0,022). Particularmente, maior irregularidade foi observada no domínio “atividades” no grupo de pacientes (p=0,001). Nossos resultados também mostraram uma correlação positiva entre a idade de diagnóstico e o domínio “sono” da BRIAN-K (r=0,485; p=0,03). Conclusões: Estes dados preliminares sugerem que a versão BRIAN-K, recentemente adaptada para crianças e adolescentes, é capaz de discriminar pacientes com THB e controles. Futuros estudos com maior tamanho amostral são necessários para determinar a confiabilidade, a validade interna e externa do presente instrumento.

Background: Alterations in the circadian rhythms have been frequently observed in patients with Bipolar Disorder (BD). However, there are few instruments to measure these changes, and most of them only assess sleep disorders. The BRIAN scale validated for adults with BD, evaluates the regularity of the biological rhythms in four different aspects: sleep, activities, social rhythm, and eating pattern. The objective of this pilot study was to adapt the BRIAN scale to a sample of children and adolescents (BRIAN-K) and to evaluate if the new instrument is capable of detecting differences among patients and healthy controls. Methods: Twenty patients with BD, aged between 8 and 16 years, and 32 controls matched for gender and age were included. Participants were assessed using the clinical interview Schedule for Affective Disorders and Schizophrenia for School Aged Children (K-SADS-PL) and cognitive testing. The BRIAN-K was administered to both groups. Results: The group of patients with BD had higher scores of alterations in the circadian rhythms according to the BRIAN-K total score when compared to the control group (p=0.022). Particularly, more irregularity was found in the “activities”domain in the group of patients (p=0.001). Our results have also showed a positive correlation between the age at diagnosis and the “sleep” domain of the BRIAN-K(r=0.485; p=0.03). Conclusions: These preliminary data suggest that the BRIAN-K version, recently adapted for children and adolescents, can differentiate patients and controls. Future studies with a larger sample size are necessary to determine the reliability, as well as the internal and external validity of the present instrument.

Alteraciones del ciclo circadiano en las enfermedades psiquiátricas: papel sincronizador de la melatonina en el ciclo sueño-vigilia y la polaridad neuronal / Circadian cycle alterations in psychiatric diseases: melatonin role as a synchronizer of sleep-awake cycle and the neuronal polarity

Circadian rhythms are oscillations of physiological functions. The period of their oscillation is about 24 h, and can be synchronized by environmental periodic signals as night-day cycle. The endogenous periodical changes depend on various structural elements of the circadian system which consists of the effectors, the secondary oscillators, the synchronizers and the circadian pacemaker. In mammalian species, the physiological function better understood respect their oscillation pattern are the synthesis and release of several hormones (i.e. cortisol and melatonin), the body temperature, the sleep-awake cycle, the locomotive activity, cell proliferation, neuronal activity among other rhythms. The Suprachiasmatic nucleus is the main circadian pacemarker in mammals; its oscillation keeps the circadian system synchronized particularly with respect to the environment photo period. When light reaches the pigment melanopsin in ganglionar neurons in the retina, the photoperiod signal is sent to Suprachiasmatic nucleus, and its postsinaptic neurons distributes the temporal signal to pheripheral oscillators by nervous or humoral pathways. Among the oscillators, the pineal gland is a peripheral one modulated by Suprachiasmatic nucleus. At night, the indolamine melatonin is synthesized and released from pinealocytes, and reaches other peripheral oscillators. Melatonin interacts with membrane receptors on Suprachiasmatic nucleus pacemarker neurons, reinforcing the signal of the photoperiod. In mammals, exogenous melatonin synchronizes several circadian rhythms including locomotive activity and melatonin release. When this indolamine is applied directly into the Suprachiasmatic nucleus, it produces a phase advance of the endogenous melatonin peak and increases the amplitude of the oscillation. In humans, melatonin effect on the circadian system is evident because it changes the circadian rhythms phase in subjects with advanced sleep-phase syndrome, night workers or blind people. Also it reduces jet lag symptoms enhancing sleep quality and reseting the circadian system to local time. Melatonin effects on circadian rhythms indicate their role as a chronobiotic, since decreased daily melatonin levels that occur with age and in neuropsychiatric disorders are associated with disturbances in the sleep-awake cycle. In particular, it has been described that Alzheimer's disease patients have disturbed sleep-awake cycle and have decreased serum melatonin levels. Sleep disorders in Alzheimer's disease patients decrease when they are treated with melatonin. Moreover, sleep disturbances have been observed in bipolar disorder patients and often precede relapses of insomnia-associated mania and hypersomnia-associated depression. These disturbances are linked to delayed- and advanced- phases of circadian rhythms or arrhythmia; therefore, it has been suggested that bipolar disorder patients could be treated with light and dark therapy. In depressed patients, the levels of melatonin are low throughout the 24 hour period and have a delayed onset of the indolamine concentration and showed an advance of its peak. Schizophrenic patients have decreased levels in the plasmatic melatonin in both phases of the light-dark cycle. Melatonin administration to these patients increases their sleep efficiency. In addition, melatonin acts as a neuroprotector because of its potent antioxidant action and through its cytoskeletal modulation properties. In neurodegenerative animal models, its protector effect has been observed using okadaic acid. This neurotoxin is employed for reproducing cytoskeletal damage in neurons and increased oxidative stress levels, which are molecular events similar to those that occur in Alzheimer's disease. In N1E-115 cell cultures incubated with okadaic acid, the administration of melatonin diminishes hyperphosphorylated tau and oxidative stress levels, and prevents the neurocytoskeletal damage caused by the neurotoxin. Although it is known that melatonin plays a key role in the circadian rhythms entrainment, little is known about its synchronizing effects at molecular and structural level. In algae, it has been observed a link between morphological changes and the light-dark cycle and it is known that shape is determinated by the cytoskeletal structure. In particular, the alga Euglena gracilis changes its shape two times per day under the effect of a daily light-dark cycle. This alga has a long shape when there is a higher photosynthetic capacity at the half period of the day; on the contrary, it showed a rounded shape at the end of 24 h cycle. Also, the influence of the cell shape changes on the photosynthetic reactions was investigated by altering them with drugs that disrupt the cytoskeletal structure as cytochalasin B and colchicine. Both inhibitors blocked the rhythmic shape changes and the photo-synthetic rhythm. Moreover, there are some reports about cytoskeletal changes in plants targeted by circadian rhythms. Guarda cells of Vicia faba L. showed a diurnal cycle on the alpha and beta tubulin levels. In addition, it has been proposed that melatonin synchronizes different body rhythms through cytoskeletal rearrangements. In culture cells, nanomolar melatonin concentrations cause an increase in both the polimerization rate and microtubule formation through calmodulin antagonism. A cyclic pattern produced by melatonin in the actin microfilament organization has been demonstrated in canine kidney cells. Cyclic incubation of MDCK cells with nanomolar concentrations of melatonin, resembling the cyclic pattern of secretion and release to plasma produces a microfilament reorganization and the formation of domes. Studies in animals are controvertial regarding if the amount of microtubules in different tissues varies cyclically. In rats and baboons, melatonin administration or exposure of rats to darkness induced an increased number of microtubules in the pineal gland. However, in the hypothalamus, the exposure of rats to light resulted in an increase in the microtubular protein content. Similarly, (X-tubulin mRNA was augmented during the light phase in the hypothalamus, hippocampus and cortex. By contrast, in rats maintained in constant darkness, a decreased level in the tubulin content was observed in the visual cortex. Additional information on cycle variations observed in cytoskeletal molecules indicated that beta actin mRNA levels are lower during the day in the hippocampus and cortex. But no change was observed in actin protein levels in the cerebral cortex. However, increased levels of actin and its mRNA were observed in the hypothalamus. Exogenous melatonin administration at onset of night decreased the amount of actin in the hypothalamus, while the actin mRNA levels decreased when the administration was realized in the morning. In this review we will describe the synchronizer role of melatonin in the sleep-awake cycle and in the organization of cytoskeletal proteins and their mRNAs. Also, we will describe alterations in the melatonin secretion rhythm associated with a neuronal cytoskeleton disorganization in the neuropsychiatric diseases such as Alzheimer, depression, bipolar disorder and schizophrenia.

Los ritmos circadianos son patrones de oscilación con un periodo cercano a 24h que se observan en los procesos fisiológicos. En los mamíferos se han descrito funciones biológicas con regulación circádica tal como el ciclo sueño-vigilia. La administración de la melatonina, una indolamina secretada por la glándula pineal, sincroniza los ritmos circadianos. En los humanos, este efecto se ha estudiado en sujetos con síndrome de <

Regulación circadiana del comportamiento: diferencias entre especies diurnas y nocturnas / Circadian regulation of behavior: differences between diurnal and nocturnal species

La mayoría de los organismos, incluyendo los humanos, exhiben ritmos diarios de aproximadamente 24 horas en fisiología, funciones hormonales y conducta. En mamíferos, estos ritmos son controlados por un marcapasos circadiano endógeno ubicado en el núcleo supraquiasmático (NSQ) del hipotálamo que determina la organización temporal de varias conductas y procesos fisiológicos. El control circadiano de ritmos diarios difiere en especies diurnas y nocturnas pero los mecanismos que pueden explicar dichas diferencias se desconocen aún. El objetivo de esta revisión es resumir el estado actual del conocimiento sobre los relojes circadianos y de las diferencias entre especies diurnas y nocturnas.

Most organisms, including humans, show daily rhythms of about 24 hours in physiology, hormonal function, and behavior. In mammals, these rhythmsare controlled by an endogenous circadian pacemaker localized in the suprachiasmatic nucleus (SCN) of the hypothalamus that determines thetemporal organization of several behaviors and physiological processes.Circadian control of daily rhythms differs in diurnal and nocturnal speciesbut many of the mechanisms that may explain these differences remain stillunknown. The aim of this review is to summarize our current knowledge of the circadian clocks and the differences between diurnal and nocturnal species.

Ritmos biológicos en Neuroendocrinología / Biological rhythm in neuroendocrinology

Al rotar sobre su eje, la Tierra, presenta dos entornos bien definidos, el día y la noche, que existieron desde el desarrollo de la vida. Como consecuencias, los seres vivos han desarrollado mecanismos predictivos para adaptarse satisfactoriamente. El ritmo biológico más conspicuo es el del ciclo sueño/vigilia. La secuencia de transiciones entre los tres estados fisiológicos principales de nuestra vida, la vigilia, el sueño lento o no-REM (NREM) y el sueño de movimientos oculares rápidos (REM), está organizado siguiendo un estricto orden temporal bajo el control de un marcapasos central, los núcleos supraquiasmáticos hipotalámicos (NSQ). Los NSQ preparan para anticipar el período de vigilia al controlar los dos sistemas principales de comunicación en el organismo, el sistema endocrino y el nervioso autónomo. En los humanos tanto el sueño como la secreción de hormonas son controlados por un sistema de doble comando representado por procesos homeostáticos predictivos y reactivos. Los mecanismos de la homeostasis reactiva relacionan la profundidad del sueño con la duración de la vigilia precedente mientras que los mecanismos circadianos juegan un papel fundamental para determinar el comienzo del sueño y la duración relativa de las fases de sueño REM y NREM Para la mayoría de las hormonas adenohiposisarias, su ritmicidad de 24 horas es producto de la interacción del reloj circadiano con el homeostato de sueño e incluye a los componentes pulsátiles, ultradianos de alrededor de 90 min. tiempo semejante al transcurrido entre cada sueño NREM y REM. Estos ritmos hormonales dependen principalmente del homeostato del sueño (p.ej.:GH, prolactina), del reloj circadiano (p.ej.:cortisol, melatonina) o de ambos (p.ej.:TSH). Esta revisión discute de las bases moleculares y fisiológicas del sistema circadiano haciendo énfasis en la regulación neuroendocrina.

Ritmos biológicos en Neuroendocrinología / Biological rhythm in neuroendocrinology

Al rotar sobre su eje, la Tierra, presenta dos entornos bien definidos, el día y la noche, que existieron desde el desarrollo de la vida. Como consecuencias, los seres vivos han desarrollado mecanismos predictivos para adaptarse satisfactoriamente. El ritmo biológico más conspicuo es el del ciclo sueño/vigilia. La secuencia de transiciones entre los tres estados fisiológicos principales de nuestra vida, la vigilia, el sueño lento o no-REM (NREM) y el sueño de movimientos oculares rápidos (REM), está organizado siguiendo un estricto orden temporal bajo el control de un marcapasos central, los núcleos supraquiasmáticos hipotalámicos (NSQ). Los NSQ preparan para anticipar el período de vigilia al controlar los dos sistemas principales de comunicación en el organismo, el sistema endocrino y el nervioso autónomo. En los humanos tanto el sueño como la secreción de hormonas son controlados por un sistema de doble comando representado por procesos homeostáticos predictivos y reactivos. Los mecanismos de la homeostasis reactiva relacionan la profundidad del sueño con la duración de la vigilia precedente mientras que los mecanismos circadianos juegan un papel fundamental para determinar el comienzo del sueño y la duración relativa de las fases de sueño REM y NREM Para la mayoría de las hormonas adenohiposisarias, su ritmicidad de 24 horas es producto de la interacción del reloj circadiano con el homeostato de sueño e incluye a los componentes pulsátiles, ultradianos de alrededor de 90 min. tiempo semejante al transcurrido entre cada sueño NREM y REM. Estos ritmos hormonales dependen principalmente del homeostato del sueño (p.ej.:GH, prolactina), del reloj circadiano (p.ej.:cortisol, melatonina) o de ambos (p.ej.:TSH). Esta revisión discute de las bases moleculares y fisiológicas del sistema circadiano haciendo énfasis en la regulación neuroendocrina. (AU)