Obesity Clinical Trials

The goal of this study is to uncover sleep and circadian mechanisms contributing to adverse metabolic health. The protocol is a 21 day (7 outpatient days, 14 inpatient days) mechanistic randomized-crossover study designed to identify the impact of chronic sleep restriction and circadian timing, independently and in combination on energy metabolism and identify the independent and combined effects on glucose tolerance. Read Less

Study Purpose: The combination of caloric restriction and exercise is the most common first-line treatment for obesity-related disorders, yet we know very little about how these two very different treatments work together. A deeper understanding about mechanisms underlying the health benefits of adding exercise to a weight loss program will not only aid efforts to optimize more effective lifestyle interventions, but it can also uncover novel targets for the treatment/prevention of obesity-related diseases. Although a reduction in body fat is the fundamental adaptation to weight loss, we know almost nothing about the effects that adding exercise has on structural and functional changes within fat tissue that may further enhance metabolic health. This is very important because many obesity-related metabolic health complications are tightly linked with abnormalities in abdominal fat tissue. We argue exercise-induced modifications in abdominal fat tissue will reveal persistent health benefits even if some weight is regained Study Summary: 10% Weight Loss Phase - Subject participation in the study will involve a series of metabolic tests before, at midpoint, and after undergoing a 10% weight loss program (with or without exercise training depending on group randomization). During this, subjects will be randomized into one of two different experimental groups: 1. Moderate Intensity Continuous Training (MICT) exercise group 2. No exercise (control) group Follow-up Phase: After completing the metabolic testing post-weight loss, all study-related diet and exercise supervision will end and subjects will be free to make their own choices regarding diet and exercise/physical activity behavior. Subjects will then be asked to complete follow-up testing at 2-, 4- and 6- months post-weight loss. Total involvement in the study for each subject will likely be about 10-13 months (4-7 months during weight loss phase, 6 months during follow-up phase). Read Less

Purpose of the Study: This study is to learn more about how exercising at different times of the day (morning versus evening) affects metabolism of glucose in the body, sleep, activity outside of exercise, and other factors. Procedures: * 2 screening visits to make sure you are eligible to be in the study. This will include a fasting blood draw and heart tracing (EKG). * If you are eligible, you will complete both exercise conditions in a random order. All participants in the study will complete the following separated by 3-4 weeks: * Baseline condition of NO exercise * Morning exercise for 3 days in a row * Evening exercise for 3 days in a row * You will be provided with an example diet to follow for the days you are completing the baseline and exercise conditions (three days total for each condition). This diet will be a "traditional" diet with a controlled amount of carbohydrates, protein, and fat per day. The investigators will provide you with examples of meals to eat during this time. * You will be asked questions and complete questionnaires about your health history, sleeping and awakening habits, and sleepiness levels. * You will undergo one x-ray scan to measure your level of body fat. * You will be asked to wear an activity monitor and sleep monitor for 6 days in a row three times during this study. * You will be asked to wear a continuous glucose monitor (CGM) for 6 days in a row three times during this study. * You will be asked to measure your saliva melatonin levels three times in the study. This will be done once per hour for 5 hours (a total of 6 saliva samples). * You will be asked to complete a procedure called a "hyperinsulinemic-euglycemic clamp" where you will have an IV placed and insulin and glucose infused with frequent lab and finger stick blood sugars monitored closely. This will be done 3 times during the study. Read Less

The purpose of this study is to evaluate endoscopic sleeve gastroplasty (ESG) for the treatment of obesity. The ESG procedure is an U.S. Food and Drug Administration (FDA) approved procedure for the treatment of obesity - patients with a body mass index (BMI) 30-50 kg/m2. This procedure is FDA approved; however, Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP)-Accredited centers (such as Houston Methodist Hospital) must receive approval from an Institutional Review Board (IRB) in order to perform primary procedures, such as ESG, that are not endorsed by the American Society for Metabolic and Bariatric Surgery (ASMBS). Read Less

Primary care settings lack interventions to address the childhood obesity epidemic that are feasible and sustainable without requiring significant resources. The investigators propose to modify and test an intervention shown to lower children's body mass index(BMI) so that it is feasible, sustainable, and easily disseminated in a real-world clinical setting. If successful, the investigators will be able to provide recommendations to providers and health care systems that help prioritize future intervention strategies and research investments to reduce obesity in children that can be quickly translated into other settings and widely adopted after the study period, with the goal of halting and reversing the childhood obesity epidemic. Read Less

The investigators have preliminary data suggesting that obese patients with hypogonadotropic hypogonadism (HHG) have minimal benefit from testosterone therapy likely because of its conversion to estradiol by the abundant aromatase enzyme in the adipocytes. The increased conversion of androgens into estrogens in obese men results in a negative feedback of high estradiol levels on hypothalamus and pituitary, inhibiting the production of gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH) and follicle stimulating hormone (FSH) and, as a consequence, of testosterone by the testis. Testosterone administration could increase estradiol production, further promoting the inhibitory feedback to the hypothalamic-pituitary-gonadal axis. Although weight loss from lifestyle modification has been shown to reduce estradiol and increase testosterone levels, the effect is at best modest and weight regain results in recurrence of hypogonadism. The use of aromatase inhibitors, in combination with weight loss, could be an effective alternative strategy due to its action at the pathophysiology of the disease. Intervention Subjects (body mass index of ≥35, testosterone \<300 ng/dl) will be randomized to the active (anastrozole) or control (placebo) group. Anastrozole 1 mg tablet / day will be self-administered with or without food, at around the same time every day (active group); placebo 1 tablet/day with or without food to take at around the same time every day (control group). The study duration will be 12 months. Both groups will undergo lifestyle intervention consisting of diet and supervised exercise program. Target weight loss will be at least 10% of baseline body weight during the intervention. Subjects will attend weekly group behavior modification sessions which will last \~75-90 min for the first 3 months and decreased to every two weeks from 3 to 12 months. Subjects will attend supervised research center-based exercise sessions during the first 6 months followed by community fitness center-based sessions during the next 6 months for at least 2 d/wk, with recording of home-based exercises for the other 2-4 days/week. Read Less

The purpose of this study is to establish and follow longitudinally a cohort of ethnically diverse pregnant women and their offspring, in order to explore the hypothesis that fetal over-nutrition is associated with obesity, metabolic, and cardiovascular abnormalities in the offspring. Read Less

This is a prospective, observational study to investigate molecular mechanisms mediating the systemic inflammatory process, and changes to metabolism, and their impact on brain injury, survival, and functional outcomes after cardiac arrest. Investigators have shown that cardiac arrest induces changes in the numbers and properties of circulating immune cells, shifting the balance towards a pro-inflammatory phenotype and there is increased interest in the inflammatory pathways and the signaling mechanisms through which they are modulated. Participants will undergo blood sampling during 7 days following cardiac arrest, and analyses performed. Patient characteristics, clinical circumstances, and outcomes will be recorded and their associations with these inflammatory pathways characterized. Read Less

Nonalcoholic fatty liver disease (NAFLD) is now the most common liver disease worldwide and affects nearly 40% of obese youth and up to 10% of the general pediatric population. Some features of NAFLD are similar in children and adults, yet fibrosis and inflammation are more common in the portal zone and occur earlier in pediatric NAFLD patients than adults. This portends a rapid progression to end-stage liver disease in early adulthood. For the majority of children with NAFLD, mechanisms driving the origin and rapid progression of disease remain unknown. Thus, there is a critical, unmet need to study the specific underlying patterns of metabolic and molecular changes in the liver underlying the development and progression unique to children with NAFLD. This proposal will test the hypotheses that children with NAFLD have excess glucose and lipid produced by the liver, that those events are regulated by specific variations in the amount and location of RNAs and proteins in liver, and that the concentration of specific micro-RNAs in the blood can be used as a biomarker for NAFLD in pediatric patients. Read Less

The purpose is to optimize the EMPOWER program by integrating strategies to reduce food cravings, a critical yet often overlooked factor for long-term success in weight management. The objective of this study is to determine the efficacy of craving coping strategies on weight loss outcomes by conducting a randomized controlled trial. Participants will be randomized to receive one of the two strategies to manage food cravings. Read Less

Reduction in food reinforcement appears to be a principal way by which bariatric surgery lowers energy intake to promote weight loss and other health improvements. However, surgical modulation of mechanisms that influence food reinforcement is variable with some patients appearing more resistant to these effects than others. This "resistant" phenotype, characterized by high levels of hedonic hunger (i.e., eating for pleasure in the absence of hunger) and disinhibition (i.e., susceptibility to cues that promote overeating), can undermine surgical efficacy. Bariatric surgery patients who demonstrate this high-risk eating phenotype may benefit from strategies that can directly target neural mechanisms of food reinforcement. Repetitive transcranial magnetic stimulation (rTMS), a noninvasive procedure that delivers magnetic pulses to stimulate or inhibit nerve cells in the brain, has successfully been used to target dysregulated brain reward circuitry to diminish the reinforcing properties of addictive drugs, such as cocaine. rTMS might have a similar effect on people who have a strong drive to eat in response to the reward of palatable foods. No study has directly examined how rTMS impacts the reinforcing value of food and related brain reward processing among people who find food highly reinforcing. The reinforcing value of food can be measured by comparing how much work a person will choose to do to access that food versus an alternative reinforcer (i.e., relative-reinforcing value of food \[RRV\]). In this study, we aim to: (1) determine whether rTMS reduces the RRV relative to money; and (2) measure acute rTMS-induced modulation of reward processing with electroencephalography (EEG). Preoperative bariatric patients (n=10) will attend 2 study sessions, at least 1-week apart, with RRV and reward measures completed while EEG is collected before and after a rTMS session. With condition blinding and counterbalancing, participants will be randomized to active rTMS on one day and sham rTMS on the other day. Participants will arrive fasted in the morning, receive a standardized breakfast, complete the RRV and reward tasks during EEG before rTMS (pre-rTMS EEG), receive rTMS, then complete the RRV and reward tasks during EEG after rTMS (post-rTMS EEG). During the active condition, rTMS will be applied to the dorsolateral prefrontal cortex because this region is functionally and structurally connected to the striatum, an area necessary for reward processes. These procedures will allow for comparison of pre- to post-test rTMS changes in behavioral (RRV) and neural modulation (EEG) of food reward between the active and sham conditions. Read Less

The overall objective of the study is to examine the effect of an 8-hour time-restricted eating intervention on lipid levels and body composition in peri- and recently postmenopausal women with untreated dyslipidemia. Read Less