View clinical trials related to Circadian Rhythms.
Filter by:The purpose of this project is to improve our understanding of peripheral circadian rhythms in humans. Circadian clocks are present in most tissues of the body with importance for optimal physiological function, health, and behavior. This project will utilize simulated jetlag protocols to systematically test novel hypotheses about the regulation of peripheral circadian rhythms in humans. Specifically, we will examine how changes in the time of when we are exposed to light and the timing of when we eat impacts proteins in the blood and saliva that represent rhythms from clocks in the brain (e.g., rhythms of the hormones melatonin and cortisol coordinated by the brain) and rhythms from clocks in body tissues (e.g., proteins made by immune and bone cells, and cells in the stomach and liver). We also aim to discover new blood-based biomarkers of peripheral rhythms in humans. We anticipate our findings will be the first step in developing novel circadian based treatments for aligning peripheral clocks under conditions such as jetlag, and for developing novel circadian biomarkers that will advance our scientific understanding of circadian rhythms.
Sleep problems are common among adolescents which can have a variety of serious biological, emotional, cognitive and psychological consequences. Numerous studies have shown that adolescents who suffer from insufficient sleep and poor sleep quality experience decreased mental well-being which is a growing concern in modern societies. Effective interventions that enhance sleep quality among adolescents are lacking. One possible reason for sleep problems among adolescents is disturbance in the body's circadian rhythms. As light is known to be the main coordinating factor in circadian rhythms, light therapy is an auspicious method which aims to entrain the circadian rhythms, thereby enhancing sleep quality and well-being. Indeed, bright light therapy (BLT) has been shown to be a promising treatment to improve sleep and decrease depressive symptoms among different patient groups. However, BLT interventions among healthy adolescents are needed. Therefore, the current study will investigate whether BLT in classrooms of 16 year old students can improve their sleep quality and well-being. The results from the study can be important as it is the first one to examine whether light intensity in the classroom affects sleep and well-being among adolescents. Furthermore, if the hypothesis will be supported, a simple and relatively inexpensive method can be implemented to promote better sleep quality and thus have an extensive effect on adolescents' well-being. Aim 1 - Assess whether BLT will improve sleep quality of adolescents. Aim 2 - Assess whether BLT will decrease depressive symptoms in adolescents. Aim 3 - Assess whether BLT will improve mood in adolescents.
This study is a mechanistic clinical trial designed to investigate the effects of the circadian system and sleep on non-dipping blood pressure (BP) in people with hypertension (HTN).
Severe fatigue, depression, sleep problems and cognitive impairment are the most commonly reported side effects of cancer treatment. These aversive side effects are hypothesized to be related to the disruption of circadian rhythms associated with cancer and its treatment. Exposure to Bright White Light (BWL) has been found to synchronize the circadian activity rhythms but research with cancer patients has been scarce. Therefore, the proposed randomized control trial (RCT) will test if systematic light exposure (sLE) will minimize overall levels of cancer-related fatigue (CRF), depression, sleep problems and cognitive impairment among breast cancer patients undergoing breast cancer treatment (i.e., surgery, chemotherapy). SLE incorporates the delivery of harmless UV-protected BWL or Dim White Light (DWL - standard comparison in light studies) delivered to patients by using special glasses for 30 minutes each morning, during their treatment. The proposed study, including a delineated comparison condition, will investigate the effects of BWL on CRF, sleep, depression, cognition, circadian rhythms, and inflammation markers among patients undergoing breast cancer treatment. The proposed RCT could have major public health relevance as it will determine if an easy-to-deliver, inexpensive, and low patient burden intervention reduces common side effects (e.g., CRF, depression, cognitive impairment) of cancer treatment (i.e., surgery, chemotherapy). Aim 1 - Assess whether Bright White Light (BWL) compared with Dim White Light (DWL) among breast cancer patients undergoing breast cancer treatment will minimize overall levels of CRF, depression, sleep problems, and cognitive impairment during and after breast cancer treatment, compared to healthy controls. Aim 2 - Determine whether the BWL intervention affects cortisol rhythms, circadian activity rhythms, melatonin rhythms, and inflammation markers that have been identified as correlates/causes of cancer-related side effects (e.g., CRF, depression, sleep problems). Aim 3 - Exploratory: Explore whether the effects of BWL compared to DWL on the cancer-related side effects (e.g., CRF, cognitive impairment) are mediated by the beneficial effects of the BWL in synchronizing circadian rhythms. Aim 4 - Exploratory: Explore potential moderators of the intervention including seasonality, chronobiology, personality, and social factors.
This study will test will how eating on a particular daily schedule may effect energy, weight gain or loss, and body temperature.
Recent work has established biological rhythms in human skeletal muscle. It remains unknown how the timing and pattern of meals influences these rhythms. Therefore, this study sets out to establish how frequent (CONSTANT) vs infrequent (BOLUS) feeding patterns influence established biological rhythms in skeletal muscle.
Recruitment of obese children, classification according to sleep questionnaire and randomization in two groups to perform nutritional and sleep intervention. . One group receives dietary intervention through recommendations. A group receives dietary and sleep intervention through recommendations. An analysis of the melatonin profile and metabolic and inflammatory status is performed by biochemistry at the beginning and end of the intervention. Determine if the intervention has improved the health of obese children.
The purpose of this study is to test the hypothesis that the disruption of the "normal" (three meals a day) eating pattern and prolonged overnight fasting caused by skipping breakfast: i) alters the expression of specific clock genes and clock gene targets involved in regulating adipose tissue lipolysis (breakdown or destruction); ii) increases basal adipose tissue lipolytic (breakdown) activity and plasma free fatty acid (FFA) concentrations; iii) reduces skeletal muscle insulin sensitivity; and iv) increases daylong plasma glucose, FFA, and insulin concentrations. The investigator will do this by studying healthy, lean persons either randomized to consume either 3 standard meals per day or omit breakfast and consume 2 meals per day without changing daily calorie intake (skipping breakfast group).